4,755 Matching Annotations
  1. Aug 2022
    1. Reviewer #3 (Public Review):

      In this manuscript by Ardiel et al, the authors develop a novel automated approach to behavioral classification of C elegans embryos. They provide detailed validation of this system, and in exploiting it, identity a previously unknown period of behavioral quiescence in the late embryo that is likely dependent on synaptic transmission. Then shifting to a high throughput assay to focus on this specific period, they provide evidence for a sleep/quiescent like state. The highly technical approaches they develop can potentially be used by many labs, and the rich behavioral dataset can likewise serve as a foundation for numerous future studies. However, I have major concerns. Foremost is that at its core, there are very limited new biological conclusions to come out of this work, which will dampen impact of the techniques described. Other major issues:

      1. The period of quiescence/SWT is intriguing, though I believe the authors are premature in their conclusions. SWT shares molecular features of worm sleep, but the work does not go far enough to prove quiescence. Are the animals paralyzed? Does SWT have features of sleep homeostasis? I do not think the authors need to prove every feature exhaustively, but at a minimum, should demonstrate that it is a reversible state. Moreover, the authors convert midway through the work to calling this slow wave twitch (SWT). These are all words that are likely chosen specifically to evoke a sense of "sleeping" from readers, but the behavior does not really seem like twitching, and are these really slow waves?

      2. For the high throughput portion, the authors find some mutants that disrupt SWT. they should also test to see whether earlier embryonic behaviors are affected (as was tested with unc13), as this would very much alter the interpretation

      3. The Discussion really overreaches. There is a heavy focus on sleep and autism, despite no clear evidence that SWT is sleep. I certainly agree discussions can be speculative, but the tone here seems to make claims that are absolutely not supported by the data. I would suggest ending the manuscript with "Together, these similarities suggest that SWT may be akin to the developmentally timed sleep associated with each larval molt" which underscores to readers that the data really ends short of showing SWT is indeed sleep.

      4. The manuscript feels disjointed as a whole in some respects, as the authors put huge effort into the methodology of Figures 1-4, and then completely shift approaches. Perhaps they can reframe the work to better emphasize how MHHT led to an important biological discovery, and then better justify why moving to a new system was necessary. Also important - the manuscript portion describing Figs 1-4 is so technical that most readers will not be able to follow. Perhaps there are ways to better hand hold for a broad audience.

      5. Fig 6g attempts to show that the correlation between RIS calcium transients and motion is reduced in FLP-11 mutants. While this reduction is evident, it still seems like a very strong correlation, undercutting the idea that FLP-11 is required for SWT, as it is for sleep. This further calls into question whether SWT is the same at lethargus.

    1. Reviewer #3 (Public Review):

      Argenty et al. investigated the role of Lissencephaly gene 1 (LIS1), a dynein-binding protein, in thymic development and T cell proliferation. They find that LIS1 is essential for the early stages of T and B cell development, and demonstrate that loss of LIS1 has a negative impact on the transition from DN3 to DN4 thymocytes and on the maturation of pre-pro-B cells into pro-B cells in the bone marrow. Using a CD2Cre Lis1fl/fl murine model, they observe that in thymocytes LIS1 is critical for DN3 proliferation and completion of cell division. Then, using a CD4Cre Lisfl/fl model (Cd4 promoter is up-regulated just in later stages of thymic development and, thus, does not impact DN3 thymocytes) they show that LIS1-deficient CD4 T cells have proliferation defects following both TCR-dependent or -independent stimulation, which results in apoptosis. They also confirm previous reports that show that LIS1-deficient CD8 T cells do not have their proliferation impaired upon TCR stimulation, which suggests that these two cell types rely on different mechanisms to regulate the cell cycle. Finally, the authors make efforts to determine how LIS1 regulates proliferation in thymocytes and CD4 T cells. Interestingly, they show that LIS1 is important for chromosome alignment and centrosome integrity and provide data that support a model where LIS1 would facilitate the assembly of active dynein-dynactin complexes. These data provide interesting insights into how different cell types use distinct strategies to undergo mitosis and how this can impact on their proliferation and fate decisions. The conclusions of the manuscript are mostly supported by the provided data, although certain aspects can be further investigated and clarified.

      Strengths of the paper:

      By combining a re-assessment of previous reports with new findings, the data from this manuscript convincingly demonstrates that LIS1 is crucial for cell proliferation in certain development steps/cell types. Furthermore, the manuscript provides clear evidence of how LIS1 loss causes proliferation defects by disrupting centrosome integrity and chromosome alignment both in CD4+ T cells and thymocytes.

      Weakness of the paper:

      Although authors successfully address the mechanistic role of LIS in thymocyte and CD4+ T cell division, the manuscript would be strengthened by both providing further evidence to support some of their conclusions and a review of some speculations raised in the discussion.

      In Figure 1, the authors claim that LIS1 is not required for pre-TCR assembly, but for expansion/proliferation of DN3 thymocytes as a step prior to reaching the DN4 stage. However, authors indeed observe increased expression of CD5 (which is a downstream event of Notch and IL-7R signalling). Thus, from the data provided it is not clear whether signalling through Notch or IL-7R is definitely not affected, which could be clarified by assessing the expression of other downstream targets of these molecules.

      In Figure 3, the authors mostly confirm previous data from Ngoi, Lopez, Chang, Journal of Immunology, 2016 (reference 34), but also provide evidence of a role of LIS1 in CD4+ T cell proliferation in more physiological setups, using OT2-CD4-Cre Lis1flox/flox (or OT2 Lisflox/flox as controls) in adoptive transfer experiments followed by antigen-specific immunization. However, the evidence provided by the authors about proliferation defects in LIS1-deficient cells in this context is limited by the early timepoint chosen: day 3 post-immunization.

      In the discussion, the authors speculate about the differences observed between CD4 and CD8 T cells, as the latter do now show proliferative defects upon TCR-triggered stimulation, and come up with the hypothesis that LIS1 might be important for symmetric cell divisions, but not for asymmetric cell divisions. However, the arguments used by the authors have few caveats, especially because CD4+ T cells can also undergo asymmetric cell division following TCR-triggered stimulation upon the first cognate antigen encounter (Chat et al., Science, 2007, Ref. 8).

      Finally, the authors discuss that mono-allelic LIS1 defects might contribute to malignancies. Certainly not all points raised in the discussion need to be experimentally addressed, but for this particular hypothesis the authors would likely have the tools to achieve that, which would broaden the relevance of understanding LIS1 function.

    1. Reviewer #3 (Public Review):

      This study of U1 snRNP interaction with the 5'ss is an interesting and exciting piece of work. In particular, the data support two important conclusions of general importance to the field: 1) the association of the U1 snRNP with the 5'ss is largely determined by the snRNP itself and does not require other splicing factors and 2) the ability to form "productive" (i.e. long-lived) interactions between the U1 snRNP and the 5'ss cannot be accurately predicted by base-pairing potential alone. This second point is particularly important as many algorithms for predicting splicing efficiency are based on base-pairing strength between the U1 snRNA and the 5'ss sequence. The data immediately suggest two additional questions.

      1. The authors repeatedly speculate that the benefit of basepairing toward the 3' end is due to the activity of Yhc1. If this model is true, these 3' end basepairs should not influence binding for a U1 snRNP with a mutant Yhc1. Since the authors have used mutant Yhc1 in other studies it seems possible to test this prediction.

      2. Since splice sites are often "found" in the context of alternative or pseudo/near-cognate splice sites, it would be interesting to know how the "rules" identified in the experiments presented in this study influence splice site competition and whether both the short- and long-lived states are subject to competition or, rather, only the short-lived complexes. Is it possible to repeat the CoSMoS experiment with two oligomer sequences of different colors?

      3. Finally, the authors should say more about the particular requirement for basepairing at position 6, especially in the context of the experiments in Figure 5. This is particularly striking as this position is not well conserved in natural 5'ss, at least compared to position 5.

    1. Reviewer #3 (Public Review):

      By use of in vivo fluorescence imaging and image analysis tools, Blanc et al. have established an automatic pipeline to build a digital 3D-temporal atlas of zebrafish hindbrain. Based on the common fluorescence labelling with HuCD the authors first established a pipeline and a reference atlas of the hindbrain. The pipeline is based on the already established tools in Fiji for registration of multi-modal data, such as Fijiyama plugin, and automatic segmentation of the data, in particular Weka 3D segmentation. By use of this pipeline, the authors then mapped rhombomeres markers Mu4127, precursor cell populations by nestin, Neural basic helix-loop-helix (bHLH) transcription factor neurog1 expressed in proliferating cells, motoneurons by isl1, and glutamatergic and GABAergic neurons via vglut2 and gad1b correspondingly. All these cell populations were mapped precisely from 24 to 72 hpf of zebrafish brain development. By comparison of fluorescent marker expression in a temporal manner, the authors demonstrate that one can approximate the birthdate of cells for which reporter expression is delayed and becomes present only later.

      Strengths:<br /> Free and easy access to Fiji plugins used and developed in this work makes the building of digital 3D atlases accessible for many labs, potentially also in other settings. The analysis of marker expressions in space, that is anterior-posterior and mediolateral is simple (without the need for high computational power or specialized and expensive software) and at the same time biologically relevant.

      Weaknesses:<br /> Due to the use of fluorescence imaging, the pipeline is limited to easily accessible and rather transparent tissues. Additionally need for one channel as a common reference is time and labour extensive in terms of experimental work. In terms of the 3D digital atlas maker, the use of user supervised training limits the "easiness" and widespread use of the pipeline in the future.

    1. Reviewer #3 (Public Review):

      The manuscript by Wang et al. investigates the role of actin and an associated capping protein in cytoadherence and motility of T. vaginalis and represents a substantial amount of work. The authors first demonstrate the adherent lines and clinical isolates express high levels of actin than non-adherent lines, and that a higher percentage of actin is found in the filamentous form in these isolates. FACP was subsequently identified as an actin-binding protein in immunoprecipitation experiments. Overexpression of FACP-WT, but not overexpression of FACP lacking a putative actin-binding domain, resulted in a decreased amount of F-actin in cells, suggesting a role for FACP in limiting actin polymerization by presumably capping the barbed (+) end of filaments. Phosphorylation of FACP at serine 2, mitigates this effect demonstrating that phosphorylation is important for the actin-binding ability of FACP. Phosphorylation also leads to lower adherence to epithelial cells.

      However, a major conclusion of this paper, namely that FACP acts via a novel mechanism and binds both G and F-actin, is not supported by the data. This conclusion is based on experiments with recombinant TvActin expressed in bacteria and co-immunoprecipitation of FACP with actin. The execution of these experiments is problematic for a number of reasons:

      1) The authors state in the methods that the majority of GST-actin is found in inclusion bodies in E. coli. The protein was solubilized in 8M urea, which will denature the protein and the authors then attempted to refold actin by dialysis in G-buffer. F-actin buffer was then added to induce polymerization. The authors provide no evidence that actin folds correctly upon renaturation with G-buffer. It is quite possible that the proteins that pellet upon the addition of the F-buffer are not filaments but insoluble aggregates. I say this because (1) the assay is done at 80 picomoles, which is well below the critical concentration for most actins (typically the Cc is ~0.1-0.5uM range), and (2) the authors provide no evidence by EM or light microscopy to demonstrate that actin filaments are formed under these conditions. Inclusion of these controls in the manuscript is critical to the interpretation of all experiments which utilized the recombinant actin, including the elisa-based assay which is offered as evidence for an interaction with G-actin.

      2) In a number of experiments, the authors performed His-tagged immunoprecipitation of FACP to identify interacting proteins. Actin is found to co-IP with FACP, however, it is not clear if the immunoprecipitated actin represents an interaction with FACP with the F or G isoform. The interpretation of this data is critical for the conclusions of the paper, where the authors argue that FACP has an "atypical" mode of action (title) and the authors' conclusion (line 608) that FACP binds directly to G or F-actin.

    1. Reviewer #3 (Public Review):

      This paper examines the relative performance of linear mixed models (LMMs), principal components (PCA), and their combination (PCA-LMM) for genetic association studies in human populations. The authors claim that previous papers examining this question are inadequate and that: (i) there remains confusion on which method is best and in which context, (ii) that the metrics used in previous evaluations were insufficient, and (iii) that the simulation settings used in previous papers were not comprehensive. To fix these problems the authors perform an extensive set of simulations within several frameworks and suggest two new metrics for evaluating performance.

      Strengths:

      The simulation framework used in this paper and the extensive number of simulations provide an opportunity to examine the relative properties of the three approaches (LMM, PCA, PCA-LMM) in a variety of contexts.

      The parameters of the simulation framework are based on highly diverged populations, which is an increasingly common analysis choice that has not been examined in detail via simulation previously.

      The evaluation metrics used in this paper are AUC and a test of the uniformity of the p-value distribution under the null. This is an improvement over some previous analyses which did not examine power and relied on less sensitive tests of type I error.

      Weaknesses:

      This paper has a limited set of population frameworks just like all papers before it. The breakdown of which method is best (LMM, PCA, PCA-LMM) will be a function of the simulation framework chosen.

      The frameworks chosen for this paper are certainly not comprehensive in contemporary human genetic studies. In fact, the authors make a number of unusual choices. For example, the populations in the simulated study have extremely large Fsts. While this is also a strength, the lack of more standard study designs is a weakness. More importantly, there is no simulation of family effects, which is the basis of many of the PCA-LMM papers reported in Table 1.

      The discussion (and simulations) of LMM vs PCA, particularly LMMs with PCs as fixed effects misses the critical distinction of whether PCs are in-sample (in which case including PCs as fixed effects effectively serves as a preconditioner for the kinship matrix, speeding up iterative methods such as BOLT), or projections of individuals onto out-of-sample principal axes. There is also no discussion of LOO methods to address "proximal contamination", also quite relevant in evaluating power as a function of the number of PCs.

      There is no discussion/simulation of spatial/environmental effects or rare vs common PCs as raised in Zaidi et al 2020. There are some open questions here regarding relative performance the authors could have looked at. Same for LMMs with multiple GRMs corresponding to maf/ld bins and thresholded GRMs. For example, it would be helpful to know if multiple-GRM LMMs mitigate some of the problems raised in the Zaidi paper.

    1. Reviewer #3 (Public Review):

      To investigate the action of Ism1 and reveal the difference from insulin, the authors performed a non-biased phosphorylation proteome analysis of pre-adipocytes (3T3-F442A cells). They found that Ism1-induced signaling pathways are related to unexpected GO terms, including "protein anabolism" and "muscle." Furthermore, Ism1 enhanced Akt-mediated protein synthesis in C2C2 myotubes, and Ism1 KO mice showed weakness and decreased muscle size. Based on these data, the authors claimed that Ism1 is a novel factor in governing muscle hypertrophy and atrophy via protein synthesis.

      The new role of Ism1 in protein synthesis discovered using non-biased exhaustive analysis is a unique finding. However, they analyzed the phosphorylation cascade of Ism1 only in 3T3-F442A cells and did not compare the difference between Ism1 and the insulin signal in skeletal muscle cells. In Fig.3C, the actions of Ism1 and Igf1 are compared in C2C12 myotubes, but it is unclear whether these pathways are different. The authors did not analyze whether the protein synthesis action of Ism1 belongs to the same pathway as insulin or IGF1 or to a different pathway in skeletal muscle cells.

      As the author states in the Discussion, it is important to clarify which phase of the skeletal muscle regeneration process Ism1 influences. Single-cell RNAseq cannot analyze skeletal muscle fibers, which are large, multinucleated, terminally differentiated cells. Therefore, it is unclear whether Ism1 acts on satellite cells, myoblasts, myotube cells, or skeletal muscle fibers.

    1. Reviewer #3 (Public Review):

      The authors have performed a transcriptional analysis of young/aged hematopoietic stem/progenitor cells which were obtained from normal individuals and those with MDS.

      The authors generated an important and valuable dataset that will be of considerable benefit to the field. However, the data appear to be over-interpreted at times (for example, GSEA analysis does not have "functionality", as the authors claim). On the other hand, a comparison between normal-aged HSC and HSC from MDS patients appears to be under-explored in trying to understand how this disease (which is more common in the elderly) disrupts HSC function.

      A more extensive cross-referencing of other normal HSPC/MDS HSCP datasets from aged humans would have been helpful to highlight the usefulness of the analytical tools that the authors have generated.

      Major points

      1. The authors detail methodology for identification of cell types from single-cell data - GLMnet. This portion of the text needs to be clarified as it is not immediately clear what it is or how it's being used. It also needs to be explained by what metric the classifier "performed better among progenitor cell types" and why this apparent advantage was sufficient to use it for the subsequent analysis. This is critical since interpretation of the data that follows depends on the validation of GLMnet as a reliable tool.

      2. The finding of an increased number of erythroid progenitors and decreased number of myeloid cells in aged HPSC is surprising since aging is known to be associated with anemia and myeloid bias. Given that the initial validation of GLMnet is insufficiently described, this result raises concerns about the method. Along the same lines, the authors report that their tool detects a reduced frequency of monocyte progenitors. How does this finding correlate with the published data on aging humans? Is monocytopenia a feature of normal aging?

      3. The use of terminology requires more clarity in order to better understand what kind of comparison has been performed, i.e. whether global transcriptional profiles are being compared, or those of specific subset populations. Also, the young/aged comparisons are often unclear, i.e. it's not evident whether the authors are referring to genes upregulated in aged HSC and downregulated in young HSC or vice versa. A more consistent data description would make the paper much easier to read.

      4. The link between aging and MDS is not explored but could be an informative use of the data that the authors have generated. For example, anemia is a feature of both aging and MDS whereas neutropenia and thrombocytopenia only occur in MDS. Are there any specific pathways governing myeloid/platelet development that are only affected in MDS?

      5. MDS is a very heterogeneous disorder and while the authors did specify that they were using samples from MDS with multilineage dysplasia, more clinical details (blood counts, cytogenetics, mutational status) are needed to be able to interpret the data.

    1. Reviewer #3 (Public Review):

      The study uses a mouse animal model of sensorineural hearing loss after sound overexposure at high frequencies that mimics ageing sensorineural hearing loss in humans. Those mice present behavioural hypersensitivity to mid-frequency tones stimuli that can be recreated with optogenetic stimulation of thalamocortical terminals in the auditory cortex. Calcium chronic imaging in pyramidal neurons in layers 2-3 of the auditory cortex shows reorganization of the tonotopic maps and changes in sound intensity coding in line with the loudness hypersensitivity showed behaviourally. After an initial state of neural diffuse hyperactivity and high correlation between cells in the auditory cortex, changes concentrate in the deafferented high-frequency edge by day 3, especially when using mid-frequency tones as sound stimuli. Those neurons can show homeostatic gain control or non-homeostatic excess gain depending on their previous baseline spontaneous activity, suggesting a specific set of cortical neurons prompt to develop hyperactivity following acoustic trauma.

      This study is excellent in the combination of techniques, especially behaviour and calcium chronic imaging. Neural hyperactivity, increase in synchrony, and reorganization of the tonotopic maps in the auditory cortex following peripheral insult in the cochlea has been shown in seminal papers by Jos Eggermont or Dexter Irvine among others, although intensity level changes are a new addition. More importantly, the authors show data that suggest a close association between loudness hypersensitivity perception and an excess of cortical gain after cochlear sensorineural damage, which is the main message of the study.

      The problem is that not all the high-frequency sensorineural hearing loss in humans present hyperacusis and/or tinnitus as co-morbidities, in the same manner that not all animal models of sensorineural hearing loss present combined tinnitus and/or hyperacusis. In fact, among different studies on the topic, there is a consensus that about 2/3rds or 70% of animals with hearing loss develop tinnitus too, but not all of them. A similar scenario may happen with hearing loss and hyperacusis. Therefore, we need to ask whether all the animals in this study develop hyperacusis and tinnitus with the hearing loss or not, and if not, what are the differences in the neural activity between the cases that presented only hearing loss and the cases that presented hearing loss and hyperacusis and/or tinnitus. It could be possible that the proportion of cells showing non-homeostatic excess gain were higher in those cases where tinnitus and hyperacusis were combined with hearing loss.

    1. Reviewer #3 (Public Review):

      Fernandez et al. report results from a multi-day fMRI experiment in which participants learned to locate fractal stimuli along three oval-shaped tracks. The results suggest the concurrent emergence of a local, differentiated within-track representation and a global, integrated cross-track representation. More specifically, the authors report decreases in pattern similarity for stimuli encountered on the same track in the entorhinal cortex and hippocampus relative to a pre-task baseline scan. Intriguingly, following navigation on the individual tracks, but prior to global navigation requiring track-switching, pattern similarity in the hippocampus correlated with link distances between landmark stimuli. This effect was only observed in participants who navigated less efficiently in the global navigation task and was absent after global navigation.

      Overall, the study is of high quality in my view and addresses relevant questions regarding the differentiation and integration of memories and the formation of so-called cognitive maps. The results reported by the authors are interesting and are based upon a well-designed experiment and thorough data analysis using appropriate techniques. A more detailed assessment of strengths and weaknesses can be found below.

      Strengths

      1. The authors address an interesting question at the intersection of memory differentiation and integration. The study is further relevant for researchers interested in the question of how we form cognitive maps of space.

      2. The study is well-designed. In particular, the pre-learning baseline scan and the random-order presentation of stimuli during MR scanning allow the authors to track the emergence of representations in a well-controlled fashion. Further, the authors include an adequate control region and report direct comparisons of their effects against the patterns observed in this control region.

      3. The manuscript is well-written. The introduction provides a good overview of the research field and the discussion does a good job of summarizing the findings of the present study and positioning them in the literature.

      Weaknesses

      1. Despite these distinct strengths, the present study also has some weaknesses. On the behavioral level, I am wondering about the use of path inefficiency as a metric for global navigation performance. Because it is quantified based on the local response, it conflates the contributions of local and global errors.

      2. For the distance-based analysis in the hippocampus, the authors choose to only analyze landmark images and do not include fractal stimuli. There seems to be little reason to expect that distances between the fractal stimuli, on which the memory task was based, would be represented differently relative to distances between the landmarks.

      3. Related to the aforementioned analysis, I am wondering why the authors chose the link distance between landmarks as their distance metric for the analysis and why they limit their analysis to pairs of stimuli with distance 1 or 2 and do not include pairs separated by the highest possible distance (3).

      4. Surprisingly, the authors report that across-track distances can be observed in the hippocampus after local navigation, but that this effect cannot be detected after global, cross-track navigation. Relatedly, the cross-track distance effect was detected only in the half of participants that performed relatively badly in the cross-track navigation task. In the results and discussion, the authors suggest that the effect of cross-track distances cannot be detected because participants formed a "more fully integrated global map". I do not find this a convincing explanation for why the effect the authors are testing would be absent after global navigation and for why the effect was only present in those participants who navigated less efficiently.

      5. The authors report differences in the hippocampal representational similarity between participants who navigated along inefficient vs. efficient paths. These are based on a median split of the sample, resulting in a comparison of groups including 11 and 10 individuals, respectively. The median split (see e.g. MacCallum et al., Psychological Methods, 2002) and the low sample size mandate cautionary interpretation of the resulting findings about interindividual differences.

    1. Reviewer #3 (Public Review):

      The manuscript of Birckman and colleagues tackles the link between lineage priming, lineage specification, and cell cycle in the ESCs culture. This is an interesting piece of work, with several noteworthy findings, that elegantly explain how lineage priming can be efficiently achieved during the changing cultural conditions. There are several interesting points raised by the authors, relating to lineage priming, cell specification, and cell cycle, that can be presented to the scientific community. Namely:

      • Differential regulation of the cell cycle can tip the balance between populations of cells primed to different cell fate choices (here PrE and Epi).

      • Different culture conditions favour acceleration/stimulation of the cell cycle of different cell populations.

      • Only a small population of cells from the original culture enters a differentiation process which is followed by selected expansion and/or survival of their progeny.

      • In the case of endodermal type specification (towards PrE), a shortening of the cell cycle is accompanied by the proportional relative increase of G1 phase length.

      • FGF activity is responsible for cell cycle synchronisation, required for the inheritance of similar cell cycles between sisters and cousins

      Unfortunately, in the current version of the manuscript, the authors try to create the impression that the relationship between cell cycle, heterogeneity and cell fate found in ESCs can be directly translated to the in vivo system. It is not clear, however, how easily and reliably the information about the cell cycle in ESCs can be translated to an in vivo setting. The timeline of PrE vs Epi specification in vivo and in vitro are completely different. In embryos, PrE is specified within 24h, whereas with in vitro it takes 6 days. I cannot see how these two timelines - and also different cell cycle lengths - can be reliably compared.

    1. Reviewer #3 (Public Review):

      Mating changes behavior of female fruit flies. Authors previously reported that putrescine-rich foods increase number of progenies per mated female and mated females detect putrescine with IR76b and IR41a and are attracted to putrescine odor (Hussain, Zhang et al., 2016). In another paper, authors reported that this change of putrescine preference is mediated by sex peptide receptor (SPR) and its ligand, myoinhibiotry peptides (MIPs; Hussain, Ucpunar et al., 2016). In yet another paper, authors reported that two types of dopaminergic neurons (DANs) which innervate alpha prime 3 (a'3) or beta prime 1 (b'1) compartment of the mushroom body (MB) show enhanced response to cVA, the male sex pheromone 11-cis-Vaccenyl acetate (Siju et al., 2020). The present study investigated neural circuits that potentially link these observations.

      The authors first showed that putrescine-attraction in mated females is sustained over 7-days, which cannot be explained by SPR-MIP dependent mechanism that disappears in one week. Then they explored a factor that is transferred from males during copulation and required for putrescine-attraction in mated females. They found that blocking synaptic transmission of cVA-sensitive OR67d olfactory receptor neurons during 24 hour period of pairing with males reduces putrescine-attraction 3-5 days later (Figure 1). On the other hand, experiments with mutant flies lacking ability to generate eggs or sperms indicated that fertilization is not essential for the change in odor preference. In a proposed scenario, cVA transferred to the female during copulation activates DANs projecting to the b'1 and that in turn induces a shift in how the MB regulates the expression of polyamine odor preference, possibly by alternating activity of MB output neurons (MBONs) in the beta prime 2 (b'2) compartment.

      Some data are in line with this scenario. Blocking synaptic transmissions of Kenyon cells during mating or odor preference test reduced attraction to putrescine (Figure 2). Activation of dopaminergic neurons projecting to the beta prime 1, gamma 3 and gamma 4 in virgin females promoted attraction to putrescine when tested 3-5 days later (Figure 3). Flies expressing shibire ts1 in the MBONs in the b'1 compartment showed reduced putrescine preference when females were mated at restrictive temperature (Figure 4). Using calcium imaging and EM connectome, authors also found candidate lateral horn output neurons that may mediate putrescine signals from olfactory projection neurons to the b'1 DANs.

      This study utilized molecular genetic tools, behavioral experiments and calcium imaging to comprehensively investigate neural circuits from sensory neurons for cVA or putrescine to the learning circuits of the MB. Addressing points detailed below will strengthen a causal link between enhanced cVA response in beta prime 1 DANs and enhanced putrescine preference in mated females.

      1) The MB is the center for olfactory associative learning. It is not so surprising that 24-hour long activation of any MB cell types have long-term consequence on fly's odor preference. As authors showed in Hussain et al., 2016 and Figure S1, mated females change preference to polyamines but not ammonium. Therefore, it is important to show odor specificity of the circuit manipulations to claim that phenomenon in mated females are recapitulated by each manipulation. Wang et al., 2003 (DOI:https://doi.org/10.1016/j.cub.2003.10.003) reported that blocking a broad set of Kenyon cells impairs innate odor attraction to fruit odors and diluted odors but not repulsion.

      2) Requirement of PAM-b'1 DANs for putrescine-attraction in mated females should be demonstrated. The authors suggested existence of alternative mechanisms that may mask requirement of PAM-b'1 (Figure 3B). In a previous study, the authors reported SPR-dependent mechanism. I suggest testing the requirement of PAM-b'1 DANs in SPR mutant background or one-week after mating when SPR-dependent effect on sensory neurons disappear.

      3) Activation phenotype of MB188B-split-GAL4/UAS-dTrpA1 cannot be ascribed to activation of PMA-b'1 alone because of additional expression in DANs projecting to gamam3 and gamma4 compartments. Run the same experiment with more PMA-b'1 specific driver line.

      4) Some of EM connections are too low to be considered (e.g. two in Figure S3 and five in Figure 5). Although these connections could be functional, previous EM connectome analysis typically set much higher threshold (e.g. 10 in Hulse et al., 2021 DOI: 10.7554/eLife.66039) to avoid considering artifacts.

      5) Data for Kenyon cells (Figure 2) and LHON (Figure 6) are interesting, but not directly related to other data regarding PAM-b'1 and MBON-b'1. Due to lack of long-term changes in MBOB's odor responses in mated females (Figure 5), it is unclear what information needs to be read out from Kenyon cells and how does it affect processing of putrescine signals potentially carried by LHAD1b2.

    1. Reviewer #3 (Public Review):

      The goal of this work is to understand the role that previously neglected, unannotated ORFs play in the evolution of gene novelty in the Drosophila melanogaster lineage. These are ORFs that mostly code for small proteins, most of them having noncanonical start codons. The authors sought to identify translated ORFs using published MS proteomics datasets, making sure to achieve a balance between false positives and false negatives; they succeed rather convincingly. They then focused on when these ORFs first appeared and how they evolved, mainly aiming to understand whether some of them have emerged de novo and the evolutionary trajectories that they have taken.

      The major strengths of the manuscript lie in its scope, as it takes advantage of recently published data to exhaustively search the entire ORF catalogue of D. melanogaster for translation, in the application of rigorous methodologies for the identification of MS-supported ORFs and in the inference of the phylogenetic age of the ORF using a novel synteny-based approach. About this last point, however, I feel that some methodological details are missing. I understand that the genomic MSA of the D. melanogaster ORF and its orthologous region is extracted and that a search for the optimally aligning segment in the sequence of each species is conducted. Does that search include only ORFs in each orthologous region? I assume this is the case because the similarity cut-off of 2.5 is then calculated from protein alignments. If that is the case, why not use global alignments of entire ORFs? Furthermore, why is there no gap penalty used? Finally, I cannot see where the genomic similarity scoring part detailed in the methods is used, which adds to my confusion.

      Albeit not a major one, an additional weakness comes from the use of Latent Class Analysis to identify subpopulations of ORFs within the greater set, and examine their differences. I see why the authors did it and in theory, I have no objection, but given the small number of factors (8 if I'm counting correctly), it's unclear if it's worth the added level of complexity. Plus there's some potential bias involved since it requires binning continuous variables and hence defining bins. It seems to me that the authors could have achieved more or less the same by looking for specific subgroups based on criteria that they set themselves a priori.

      A crucial part of the work is the attribution of de novo origin to utORFs. Here, I find the initial analysis, wherein a single outgroup species is sufficient to invoke de novo origination, relatively unnecessary. Especially since the authors go on to state themselves that only two or more supporting outgroups can provide convincing evidence. I would add that at least two of the outgroups should be non-monophyletic. It is also unclear why an ORF needs to be present in the outgroups at all (and lacking significant similarity). Is there a limit to how small that ORF can be? If so, and if there happens to be no such ORF in a region, why would that not count as evidence?

      I feel that the authors achieve most of their aims, at least the ones that I perceive as the most important.<br /> There are however some findings that are not sufficiently well supported.

    1. Reviewer #3 (Public Review):

      The paper describes an ingenious and painstakingly reported method of evaluating the informativeness of clinical trials. The authors have checked all the marks of robust, well-designed and transparently reported research: the study is registered, deviations from the protocol are clearly laid out, the method is reported with transparency and all the necessary details, code and data are shared, independent raters were used etc. The result is a methodology of assessing informativeness of clinical trials, which I look forward to use in my own content area.

      My only reserve, which I submit more for discussion than for other changes, is the reliance on clinicaltrials.gov. Sadly, and despite tremendous efforts from the developers of clinicaltrials.gov (one of the founders is an author of this paper and I am well-aware of her unrelenting work to improve reporting of information on clinicaltrials.gov), this remains a resource where many trials are registered and reported in a patchy, incomplete or downright superficial and sloppy manner. For outcome reporting, the authors compensate this limitation by searching for and subsequently checking primary publications. However, for the feasibility surrogate this could be a problem. Also, for risk of bias, for the trials the authors had to rate themselves (i.e., ratings were not available in a high-quality systematic review), what did the authors use, the publication or the record from the trial registry?

      In general, it seems like a problem for this sophisticated methodology might be the scarcity of publicly available information that is necessary to rate the proposed surrogates. Though the amount of work involved is already tremendous, the validity of the methodology would be improved by extracting information from a larger and more diverse pool of sources of information (e.g., protocols, regulatory documents, sponsor documents).

      In that sense, maybe it would be interesting for the authors to comment on how their methodology would be improved by having access to clinical trial protocols and statistical analysis plans. Of course, one would also need to know what was prospective and what was changed in those protocols, i.e., having protocols and statistical analysis plans prospectively registered and publicly available. Having access to these documents would open interesting possibilities to assessing changes in primary outcomes, though as the authors say that evaluation would also require making a judgement as to whether the change was justified. Relatedly, perhaps registered reports could be a potential candidate for clinical trials that would also support a more accurate assessment of informativeness, per the authors' method, provided the protocol is made openly available.

      Still related to protocols, were FDA documents consulted for pivotal trials, which again could give an indication of the protocol approved by the FDA and subsequent changes to it?

    1. Reviewer #3 (Public Review):

      Early life trauma is a risk factor for adult aberrant aggressive behavior but this important public health issue remains under examined in the neurosciences. This study seeks to fill the gap with a mouse model of adolescent trauma that involves a combination of fearful and anxiety-provoking experiences and assessment on gene expression in brain region controlling aggression, the hypothalamus, and another controlling executive function, the prefrontal cortex. Mice are categorized for aggressive phenotype as being extreme or moderate, with the extreme being compared to controls for transcriptomic analyses of the hypothalamus and PFC. Females did not show increased adult aggression in the resident-intruder paradigm following adolescent fear and anxiety. Pathway analysis implicated the thyroid hormone pathway in male hypothalamus with the thyroid receptor, Ttr, being the top candidate gene. This formed the basis of an in depth analyses of thyroid hormone pathway and discovery of reduced T3 following adolescent stress which was causally linked to adult aggression. This is a novel observation with potentially important implications.

      The strengths of the study are the detailed behavioral analyses, inclusion of both sexes and down regulation of Ttr specifically in hypothalamus, reducing T3 and increasing aggression. The weaknesses are a lack of mechanistic explanations for how reduced T3 and T4 leads to pathological aggression in males, weakly supported claims of transgenerational inheritance, lack of consideration of other pathways and no explanation for the profound sex difference.

      Specific Comments

      1) The KEGG analyses does implicate the thyroid hormone pathway but the more consistent changes seem to be in drug addiction pathways and estrogen signaling, leaving one to wonder if the emphasis on the TH pathway is truly warranted.

      2) Aggression in females under normal circumstances is not evoked by a male intruder unless the female has a litter. Thus, it is not that surprising that the peripubertal stress did not evoke aggression in virgin females. Rather, the more interesting question is whether maternal aggression would become aberrant after peripubertal stress.

      3) Regarding the trans-generational transmission of the PPS, since the germ cells were present in the animals that were subject to PPS and gave rise to the offspring that were then tested, this is not truly transgenerational as the germ cells were residing in the stressed body. The transmission needs to be to at least the F2 generation with no stress in the F1 for this to be considered transgenerational.

      4) Regarding the methylation status of the Ttr, confidence in this result requires consideration of other targets as well in order to understand whether the epigenetic modifications are specific to just Ttr or are more widespread.

      5) The statistical analysis rests on unpaired t-tests but in most experiments a 2-way ANOVA is warranted with treatment and brain region as factors.

      6) The word "trauma" in the context used here connotes an emotional interpretation of stressful or fearful events. We do not know if the mice are experiencing trauma, instead we know they are being subject to fearful and stress-inducing experiences. It is suggested that the word trauma be removed throughout and replaced with more precise terminology.

    1. Reviewer #3 (Public Review):

      This is a very interesting and impressive manuscript. It is complex in its multiple components, and in some ways that makes it a difficult manuscript to evaluate. There is a lot in it, including empirical analyses of a face dataset and of behavioral association data, combined with a theoretical model.

      The three main findings are: 1) Paternal siblings look alike (similar to, and building on, a recent manuscript the authors published elsewhere); 2) Infants that are more facially similar tend to associate; and 3) mothers tend to be found in association with other unrelated infants that look more like their own infants. Such results are interesting, and indeed one potential interpretation, perhaps even the most likely, is that mothers are behaving in such a way that promotes association between their own infants and the paternal kin of their infants.

      Nonetheless, the evidence provided is logically only consistent with the authors' hypothesis, rather than being strong direct evidence for it. As such, the current framing and indeed the title, "Primate mothers promote proximity between their offspring and infants who look like them", are both problematic. (In addition, the title should be about mandrills, not "primates", since this manuscript does not provide evidence from any other species.) The evidence provided is consistent with the hypothesis, but also consistent with other potential hypotheses. The evidence given to dismiss other potential hypotheses is not strong, and rests on the fact that many males are not around all year to influence things, and that "males that were present during a given reproductive cycle are not responsible for maintaining proximity with either infants or their mothers (MJEC and BRT, pers. obs.)".

      My opinion is that these are really interesting analyses and data, which are being somewhat undermined by the insistence that only one hypothesis can explain the observed association patterns. It could easily be presented differently, as a demonstration that paternal siblings look alike and that they associate. The authors could then go on to explore different possible explanations for this using their association data, make the case that maternal behavior is the most plausible (but not the only) explanation, and present their model of how such behavior could bring fitness benefits.

      In my view, such a presentation would be both more cautious and more appropriate, without in any way reducing the impact or importance of the data. In the current iteration, I think there are issues because the data do not provide sufficient support for the surety of the title and conclusion, as presented.

    1. Reviewer #3 (Public Review):

      The authors critically assessed a widespread assumption that paternal biases in the number of germline mutations passed to offspring and the number of germline cell divisions have a causal link. They gather a diverse set of previously published findings that are inconsistent with this assumption, including the accumulation of maternal DNMs with age, the consistent ratio of paternal-to-maternal germline mutation (α) in humans, the range of α in mammals, and the dominance of mutational processes that are uncorrelated to cell division in human germline and somatic tissues. They then generate estimates of α based on evolutionary rates at sex chromosomes vs autosomes. They find αevo of 1-4 across the species considered, which are robust to changes/exclusion of a number of potentially confounding factors. They find an increase in αevo with generation time in mammals but not in birds. The authors consider and evaluate a model with a fixed number of early mutations for both sexes followed by post sexual differentiation stage with a paternal mutation bias.

    1. Reviewer #3 (Public Review):

      In this manuscript, Baumgartner et al investigated how cells control Rhino specific deposition on only a subset of the H3K9me3 chromatin domains to specify piRNA source loci. They identified a previously unknown protein, Kipferl, which by interacting with the chromodomain of Rhino guides and stabilizes its specific recruitment to selected piRNA source loci. Kipferl would be preferentially recruited to Guanine-rich DNA motifs. They show that in Kipferl mutant flies, Rhino nuclear subcellular localization and Rhino's chromatin occupancy changes dramatically. Then, they dissect all the domains of the Kipferl protein and show that the Rhino- and DNA-binding activities can be separated and that the 4th ZnF of Kipferl is required to interact with Rhino.

      It is a very elegant genetic work (CRISPR-edited, rescue, KD, overexpression fly lines). In addition, the authors used a combination of yeast two hybrid screen, ChIP, small-RNA-seq and imaging to dissect the function of this new protein. The data in this paper are compelling. Some conclusions might be more moderate. Even if the effect of Kipfler on 80F (Rhino binding, piRNA production) is very obvious, this study also clearly demonstrates that other protagonists are required for the specific binding of Rhino to other piRNA source loci (including 42AB and 38C).

      - Is Kipferl expressed early during oogenesis development? If Kipferl starts to be expressed only after the GSCs and cystoblast stage, Kipferl is probably not required to determine the specification of piRNA source loci identity but probably more for the maintenance of the specification. Could the authors discuss or comment on that?

      - To perform most of their ChIP-seq analysis, the authors have divided the genome into pericentromeric heterochromatin and euchromatin based on H3K9me3 ChIP-seq data performed on ovaries. With this classification the 42AB (2R:6,256,844-6,499,214) and the 38C (2L:20148259-20227581) piRNA clusters known to be heterochromatic fall in the euchromatic part of the genome. Was there a problem with the annotation?

      - Some regions exist in euchromatin that are strongly enriched in Rhino, in Kipferl and in H3K9me3 but are not producing piRNA. Does this type of region exist in heterochromatin?

      - Kipferl has been identified to interact with Rhino by a yeast two-hybrid screen (Figure 2). A co-IP which is the classical method for confirming the occurrence of this intracellular Rhino-Kipferl interaction should be provided.

      - Rhino is known to homodimerize and it has been reported that this homodimerization is important for its binding to H3K9me3 (Yu et al, Cell Res 2015). It is surprising not to find Rhino among the interactors that were picked up from the screen. Do the authors have any explanations or at least comments on these results?

      - In Kip mutants, the delocalization of Rhino to a very large structure at the nuclear periphery is a very clear phenotype (Figure 3). All the very elegant genetic controls are provided. This particular localization of Rhino is correlated with an increase in 1.688 Satellite expression and a colocalization of Rhino and the 1.688 RNAs in the nucleus. The authors propose that this increase is consistent with an elevated Rhino occupancy at 1.688 satellites. The authors should moderate their statements in the light of the results of ChIP experiments. Rhino is maintained on these loci in Kip mutants but an increase is not very clearly observed. Couldn't it be the RNA and not the DNA of this 1.688 region traps Rhino? The same in situ experiment should be performed after an RNAse treatment. The delocalization of Rhino is lost in the Kipferl, nxf3 double mutant flies. What is the chromosomal Rhino distribution in this context? Is the increase in nascent transcripts of 1.688 satellites lost?

      - The level of some Rhino dependent germline TE piRNAs is affected in Kipferl GLKD. Is there a direct correlation between TEs which lost piRNAs and those for which the level of transcripts increases (Diver, 3S18, Chimpo, HMS Beagle, flea, hobo) ?

      - Figure 5E, it seems that Kipferl binding is also dependent on Rhino. All the presented loci have much less binding of Kip in Rhino -/- (The scale for the 42AB locus should be the same between the Rhino -/- and the control MTD w-sh). In addition, the distribution of Rhino in the Kipferl-sh on the 42AB is maintained but seems to be different. Could the authors discuss these points?

      - It is not clear why the authors focus only on Kipferl binding sites in a Rhino mutant in the Figure 5D? Even if the authors mention in the text that "Kipferl binding sites in Rhino mutants ... often coincided with regions bound by Kipferl and Rhino in wildtype ovaries" it should be added the same analysis presented in figure 5D centered on Kipferl peaks detected in ChIP experiments in WT condition in the different genotypes.

      - There is a discrepancy between the results found Figure 3A and Supp figure 3B. In the Rhino mutant the level of Kipferl protein does not seem to be affected whereas in the Rhino GLKD, there is a strong decrease of Kipferl protein. The authors completely elude this point.

      - Comparing the figure 5E and the figure 6G presenting both the 80F piRNA cluster, depending of the scale and the control line that was chosen to illustrate the results we can draw different conclusions. In the figure 5E we can conclude that le level of Kipferl decreases on the 80F locus in Rhino (-/-) compared to the control MTD w-sh, whereas in the figure 6G we can conclude that the level of Kipferl is similar in the Rhino (-/-) compared to the control w1118.

      - gypsy8 or RT1b are enriched in GRGG motifs and are also the ones that among Rhino-independent Kipferl enrichment are the most Rhino enriched. Are these 2 elements present in the 80F cluster? Are these two elements derepressed upon Kipferl GLKD ? Where are these two elements in the figure presenting the change in TE transcript level upon Kipferl GLKD?

    1. Reviewer #3 (Public Review):

      This is an exciting new cryoEM structure of the HOPS tethering complex, which is necessary for membrane fusion at the vacuole/lysosome in eukaryotic cells. Finally, we can visualize, at moderate resolution, the positioning of HOPS subunits with respect to each other, and predict how HOPS and its various binding partners, such as Rab GTPases and SNAREs, can interact and control fusion. A conceptual advance put forward by this structure seems to be a rigid central core of HOPS that may contribute to helping drive the efficiency of the SNARE-mediated fusion mechanism.

      As exciting as this new structure is, however, the study seems to fall a bit short of its promise to explain "why tethering complexes are an essential part of the membrane fusion machinery, or how HOPS "catalyzes fusion." As such, the title is also misleading with regard to HOPS being the "lysosomal membrane fusion machinery."

      Overall, the manuscript could benefit greatly, especially for a non-HOPS specialist reader, in providing more introduction and context to the complex and tethering/fusion mechanisms in general. Additionally, the examination of the structure, in light of decades of biochemistry and cell biology studies of HOPS (and homologous proteins that regulate fusion), seems superficial and suggests that deeper analyses may reveal additional insights and lead to a more detailed and impactful model for HOPS function. Moreover, are the insights gained here applicable to other tethering complexes, why or why not?

    1. Reviewer #3 (Public Review):

      PME-1 catalyzes the removal of carboxyl methylation of the PP2A catalytic subunit and negatively regulates PP2A activity. Like the PP2A methyltransferase LCMT-1, PME-1 was previously thought to act only on the PP2A core enzyme. However, in this study, the authors show that PME-1 can interact and demethylate different families of PP2A holoenzymes in vitro. They also report the cryo-EM structure of the PP2A-B56 holoenzyme in complex with PME-1. Their structure reveals that the substrate-mimicking motif of PME-1 binds to the substrate-binding pocket of B56 subunit, which tethers PME-1 to PP2A, blocks substrate-binding to PP2A, and promotes PME-1 activation and demethylation of PP2A holoenzyme. Their further mutagenesis and functional analyses indicate that cellular PME-1 function in p53 signaling is mediated by PME-1 activity towards PP2A-B56 holoenzyme. In summary, this study has provided significant insights into our understanding of PP2A regulation by PME-1, demonstrating that PME-1 not only demethylates the PP2A core enzyme, but also the holoenzyme to control cellular PP2A homeostasis.

    1. Reviewer #3 (Public Review):

      The number of identified anti-phage defense systems is increasing. However, the general understanding of how phages can overcome such bacterial defense mechanisms is a black box. Srikant et al. apply an experimental evolution approach to identify mechanisms of how phages can overcome anti-phage defense systems. As a model system, the bacteriophage T4 and its host Escherichia coli are applied to understand genome dynamics resulting in the deactivation of phage-defensive toxin-antitoxin systems.

      Strengths:<br /> The application of a coevolutionary experimental design resulted in the discovery of a gene-operon: dmd-tifA. Using immunoprecipitation experiments, the interaction of TifA with ToxN was demonstrated. This interaction results in the inactivation of ToxN, which enables the phage to overcome the anti-phage defense system ToxIN.<br /> The characterization of the genomes of T4 phages that overcome the phage-defensive ToxIN revealed that the T4 genome can undergo large genomic changes. As a driving force to manipulate the T4 phage genome, the authors identified recombination events between short homologous sequences that flank the dmd-tifA operon.<br /> The discovery of TifA is well supported by data. The authors prepared several mutant strains to start the functional characterization of TifA and can show that TifA is present in several T4-like phages.

      In addition, they describe T4 head protein IPIII as another antagonist of a so far unknown defense system.

      In summary, the application of a coevolutionary approach to discover anti-phage defense systems is a promising technique that might be helpful to study a variety of virus-host interactions and to predict phage evolution techniques.

      Weaknesses:<br /> The authors apply Illumina sequencing to characterize genome dynamics. This NGS method has the advantage of identifying point mutations in the genome. However, the identification of repetitive elements, especially their absolute quantification in the T4 genome, cannot be achieved using this method. Thus, the authors should combine Illumina Sequencing with a long-read sequencing technology to characterize the genome of T4 in more detail.

      To characterize the influence of TifA during infection, T4 phage mutants are generated using a CRISPR-Cas-based technique. The preparation of these phages is unclearly described in the methods section. The authors should describe in detail whether a b-gt deficient strain was applied to prepare the mutants. Information about the used primers and cloning schemes of the Cas9 plasmid would allow the community to repeat such experiments successfully.

      The discovery of TifA would benefit from additional data, e.g. structure-based predictions, that describe the protein-protein interaction TifA/ToxN in more detail.

      Several publications have described that antitoxins can arise rapidly during a phage attack. The authors should address that this concept has been described before as well by citing appropriate publications.

      The authors propose that accessory genomes of viruses reflect the integrated evolutionary history of the hosts they infected. However, the experimental data do not support such a claim.

    1. Reviewer #3 (Public Review):

      In their study "Membrane-mediated dimerization potentiates PIP5K lipid kinase activity", Hansen et al. aim to deepen their biochemical understanding of a fascinating self-organizing system the authors have previously been reporting on (Hansen et al., PNAS 2019), in particular, the regulation of PI(4,5)P2 lipids by the kinase PIP5K, which is itself recruited to the membrane by the PI(4,5)P2. From reconstitution studies on supported membranes investigated by TIRF microscopy, following elegant assays that have they previously developed, they conclude that PIPK5 activity is regulated by cooperative binding to and membrane-mediated dimerization of the kinase domain. Dimerization enhances the catalytic efficiency of PIP5K through a mechanism consistent with allosteric regulation and amplifies stochastic variation in the kinase reaction velocity, leading to stochastic geometry sensing that has been reported earlier.

      Overall, this is a beautiful biochemical system of great general interest. Also, the findings are plausible in the light of other pattern forming systems. However, the quality of both, the writing (with partly confusing annotations, inconsistencies, and missing clarity of what is actually reported on) and the data is extremely variable, giving the whole paper a somehow immature "patchwork" impression. Not the least, error bars are missing throughout the paper, and although both the protein/membrane system and the instrumental setup seem to be sufficiently well controlled, the quantitative aspect of this study could be greatly improved.

    1. Reviewer #3 (Public Review):

      The authors describe the crystal structure of a large fragment of PKG Ib in an autoinhibited state. The structure includes both the regulatory (R) and catalytic (C) kinase domains, and shows in atomic detail how the regulatory cGMP binding domains and autoinhibitory segment bind the kinase to block its activity. A crystal structure of one of the cGMP binding domains bearing a disease-associated mutation (TAAD, Thoracic aortic aneurysms and dissections) provides an understanding of the mechanism by which the mutation leads to constitutive activation of PKG by inducing a conformation that resembles the cyclic nucleotide bound state. This interpretation is further supported by an NMR study of the mutant that reveals chemical shifts consistent with the "open" (nucleotide-bound) conformation. A structure-function study in which variants with mutations in one or both of the active sites and regulatory domain are co-expressed shows that autoinhibition occurs in cis; that is, in an intra-chain manner, rather than as part of a dimer as is likely present in the crystal. A SAXS experiment further supports this model. The authors propose a model for PKG activation, referencing the structures described here as well as prior crystal structures of the isolated kinase and regulatory domains as "snapshots" of distinct states in the autoinhibition-activation pathway. This is a careful and technically sound study that provides a first structural view of PKG autoinhibition. It also enables comparison to the related mechanism of regulation of protein kinase A, but this aspect of the manuscript could be much better developed.

    1. Reviewer #3 (Public Review):

      Carraro et al utilize systems biology approaches to decode the mechanism of action of 3-chloropiperidines (a novel class of cancer therapeutics) in cancer cell lines and build a drug-sensitivity model from the data that they evaluate using samples from The Cancer Genome Atlas and cancer cell lines. The approach provides a framework for integrating transcriptomic and open-chromatin data to better understand the mechanism of action of drugs on cancer cell types. The author's approach is of sound design, is clearly explained, and is bolstered by validation via holdout sets and analysis in new cell lines which lends the findings and approach credibility.

      The major strength of this approach is the depth of information provided by performing RNA-seq and ATAC-seq on cells treated with 3-CePs at various time points, and the author's utilization of this data to perform pairwise and crosswise analyses. Their approach identified gene modules that were indicative of why one cell type was more sensitive to a particular drug compared to another. The data was then used to build a sensitivity model which could be applied to samples from The Cancer Genome Atlas, and the authors evaluated their sensitivity predictions on a set of cancer cell lines which validated the predictions.

      The major drawback to this type of approach is that it relies on next-generation sequencing (somewhat costly) and requires intricate bioinformatics analyses. While I agree with the author's perspective that this approach can be applied to additional classes of drugs and cancer samples, I disagree with their view that it is efficient and versatile. However, for research teams with the means to perform both transcriptomic and open-chromatin studies, I think this integrated approach has promise for evaluating novel classes of drugs, particularly in cancer cell lines that are easy to manipulate in vitro.

      While there are examples of similar frameworks being applied to drug development, this work will add to the body of literature utilizing an integrated systems biology approach for pairing drugs with specific tumor or cancer types and understanding their mechanism of action on an epigenetic level.

    1. Reviewer #3 (Public Review):

      The authors sought to identify transcriptional changes that occur in the various somatic cell populations of the adult mouse ovary during different reproductive states using single-cell RNA sequencing. The ovaries for the analysis were harvested from mice during the four stages of the normal estrus cycle (proestrus, estrus, metestrus and diestrus), from lactating or non-lactating 10 days postpartum mice, and from randomly cycling mice. They identified the major cell subtypes of the adult ovary but focused their analysis on the mesenchyme (stromal and theca) and granulosa cells. They identified novel markers for stromal, theca and granulosa cell subpopulations and validated these by RNA in situ hybridization. They used trajectory analysis to infer differentiation lineages within the stromal and granulosa cell subtypes. Finally, from their data set they identify four secreted factors that could serve as biomarkers for staging estrus cycle progression.

      Strengths - This is the first study to profile ovarian somatic gonad cells at different stages of the reproductive cycle.

      Weaknesses - Enthusiasm for the current manuscript is lessened because it does not employ state-of-the-art scRNA-seq analysis. For example, once general cell populations have been determined by clustering with all cells, it is best to individually re-cluster these cell populations to identify more refined and accurate subpopulations. The PC used for the initial clustering is very useful for distinguishing different general cell populations (e.g. mesenchyme vs. granulosa vs. endothelial) but may not be as useful for distinguishing biologically relevant subpopulations (e.g. stromal subpopulations). Finally, certain cell subpopulations were excluded from the trajectory analysis without justification - specifically, the mitotic and atretic granulosa cells - calling into question what conclusions can be drawn from this analysis.

    1. Reviewer #3 (Public Review):

      The authors reanalyze an existing dataset of single-cell Sperm-seq data to search for signals of transmission distortion. They develop an improved genotype imputation method and use this approach to phase donors and characterize the landscape of ancestry across each sperm genome. Using these data, the authors determined that there are no regions in any of the male donors' genomes that display a significant excess of TD. The main biological claim of the paper is that there is a strict adherence to Mendelian transmission ratios in human males.

      The computational approaches for accurately phasing and reconstructing haplotypes in individually lightly sequenced gametes is a potentially useful advance that I expect may be valuable for geneticists analyzing similar datasets. The quality of software documentation and usability is high. I have concerns about the appropriateness of the comparisons selected for this approach and the algorithm does not appear particularly novel.

      I have no doubt about the authors' basic conclusion that there are no strong male TD loci in the male donors examined. However, I find their statements about "strict adherence to Mendelian ratios" and many references to strong statistical power to be oversold. The power of this study is still quite limited relative to the strength of TD that we would expect to find in human populations.

      Major Concerns:

      There are really two distinct papers here. One is about improved imputation and crossover analysis from sperm-seq data and one is about TD. The bulk of the methodological development is a rework of the approach for genotype imputation and haplotype phasing in Sperm-seq. Yet, the major conclusions are focused on a scan for TD. I am left wondering if analyzing these data using the original method in the Bell et al paper would have produced different conclusions about either? If not, is there a systematic bias such that one would find an excess of false detections of TD? Phasing slightly more markers is not a particularly compelling link between these sections because even fairly sparsely distributed markers that are correctly phased would certainly be fine in a scan for TD within a single individual due to linkage. If this cannot be shown I wonder if this work would be better split into two manuscripts with one more technical paper describing the differences in recombination maps associated with rhapsodi and the other as a brief report stating that strong TD is probably uncommon in human males.

      It is not surprising that rhapsodi outperforms Hapi since Hapi was designed for a very different quantity of samples and sequencing depths. I appreciate the authors' point that Hapi performed better than other methods in comparisons run by the Hapi authors. However, they were looking at very few gametes (10 or so, I believe). For that reason, this comparison is not appropriate to address the application to the datasets used in this paper. The authors should include an analysis comparing rhapsodi against hapcut2, PHMM and other methods that are appropriate for the full scale and sequencing depth of the data. Additionally, the original Bell paper used a phasing + HMM approach of some kind for exactly this data. Why wasn't that approach considered as a point of comparison?

      With respect to the method for imputation, no comparison is made to known recombination maps nor do the authors make any comparison across the maps derived from each donor. Reporting an improved method without it motivating novel biological conclusions is not compelling in itself. I suggest the authors expand that analysis to consider these are related questions. E.g., are there males whose recombination maps differ in specific regions? Are those associated with known major chromosomal abnormalities? Is this map consistent with estimates from LD, pedigrees, Bell et al?

      Most of the validations presented are based on simulated data. This is fine and has some advantages, but real data imposes challenges that these analyses do not address. My understanding is that the Bell et al. (2020) paper includes a donor with a phased diploid genome. A comparison of rhapsodi's phasing accuracy against that genome should be included.

      The main biological conclusion about a "strict adherence to Mendelian expectations across sperm genomes" is an overstatement. Statistical power of this study is still limited relative to the strength of TD that would be expected within human populations. One reason is the multiple testing correction. Another is that 1000-3000 draws from a binomial distribution with expected p = 0.5 is just not sufficient to overcome binomial sampling variance. In light of this concern and the central conclusion of this paper, the authors' discussion of power is inadequate. The main text really should contain explicit discussion of the required genotype ratio skew for TD in each donor to be detected with good power. Given previous pedigree studies, it is not surprising that no significant TD was discovered that exceeded the necessary ~10% effect sizes to be detectable. Recent, much more powerful analyses in mice, Drosophila and plants, indicate that strong TD is probably uncommon and even weak effects can be detected but are uncommon.

      This manuscript would benefit from a much clearer examination of statistical power and a detailed comparison of the power of this approach vs pedigree-based analyses as well as bulk gamete sequencing approaches. Although the authors are correct that all scans for TD in human genomes have been pedigree or single-cell based, more powerful alternatives are known. These are based on sequencing pools of individuals or gametes (e.g., Wei et al. 2017, Corbett-Detig et al. 2019). Each of those studies has been able to identify signatures of segregation distortion below the thresholds required for significance in this study. These and related works should be acknowledged in both the introduction and discussion. Although I appreciate that the ability to phase the genome in a single experiment may be appealing, phasing diploid genomes via hi-c omni-c is straightforward and the advantages in statistical power suggest that approaches using pools of gametes are preferable for well-powered scans for TD.

    1. Reviewer #3 (Public Review):

      The manuscript by Bae et al describes the role of a point mutation in the PH domain of Akt that changes the inhibition by the PH domain. The data underlying the manuscript appear to be done at a high technical level. The discovery that the R86A mutant has an enhanced inhibitory interface with the kinase domain is intriguing. Although this residue is not at the putative interface, it forms an electrostatic interaction with the Glu17 in the PH domain and causes a reorientation of the loop including the Y18. Analysis of Y18 and E17 mutants can reverse this effect, revealing a molecular mechanism of R86 increased inhibition.

      My main concern with the manuscript is that the conclusions as currently written do not appear to be fully supported by the data. Mainly on the role of the pi-pi stacking of the 309-18 interface. This paper requires a major rewrite. There also could be additional validation data included to verify the stability and phosphorylation state of the different proteins purified.

      Major concerns

      1. There are concerns about the validation of the proteins used.

      2. The authors note on page 9 that they analyzed the alphafold structure to look at the PhH-kinase interface.

      From the analysis of the alphafold model, it does not seem appropriate for this analysis, as the alphafold predicted aligned error (taken from alphafold protein structure database, https://www.alphafold.ebi.ac.uk/entry/P31749) validation clearly shows that there is only limited predictive value of the inter-domain interfaces. I am not sure the mutant data on the predicted pi stacking interaction can be supported by alphafold here as strongly as the authors describe, as these mutants may be working through a separate mechanism. The alphafold model also appears to be templated on the 4ekk phosphorylated structure/mutant of 308 and 473, which seems to go against the authors' hypothesis that 473 phosphorylation disrupts the PH domain interface.

      The best model for interpreting the Ph-kinase interface seems to be the nanobody-bound X-ray structure, and this region is disordered at F309 in this structure. While the authors' data clearly shows a role for the Y18 reorientation in changing Ph domain binding, and they also show that mutation of F309L also changes binding, they are basing their molecular model on an alphafold model with limited predictive ability for inter-domain contacts.

    1. Reviewer #3 (Public Review):

      The main goals of this study by Guan, Aflalo and colleagues were to examine the encoding scheme of populations of neurons in the posterior parietal cortex (PPC) of a person with paralysis while she attempted individual finger movements as part of a brain-computer interface task (BCI). They used these data to answer several questions:

      1) Could they decode attempted finger movements from these data (building on this group's prior work decoding a variety of movements, including arm movements, from PPC)?

      2) Is there evidence that the encoding scheme for these movements is similar to that of able-bodied individuals, which would argue that even after paralysis, this area is not reorganized and that the motor representations remain more or less stable after the injury?

      3) Related to #2: is there beneficial remapping, such that neural correlates of attempted movements change to improve BCI performance over time?

      4) Can looking at the interrelationship between different fingers' population firing rate patterns (one aspect of the encoding scheme) indicate whether the representation structure is similar to the statistics of natural finger use, a somatotopic organization (how close the fingers are to each other), or be uniformly different from one another (which would be advantageous for the BCI and connects to question #3)? Furthermore, does the best fit amongst these choices to the data change over the course of a movement, indicating a time-varying neural encoding structure or multiple overlapping processes?

      The study is well-conducted and uses sound analysis methods, and is able to contribute some new knowledge related to all of the above questions. These are rare and precious data, given the relatively few people implanted with multielectrode arrays like the Utah arrays used in this study. Even more so when considering that to this reviewer's knowledge, no other group is recording from PPC, and this manuscript thus is the first look at the attempted finger moving encoding scheme in this part of human cortex .

      An important caveat is that the representational similarity analysis (RDA) method and resulting representational dissimilarity matrix (RDM) that is the workhorse analysis/metric throughout the study is capturing a fairly specific question: which pairs of finger movements' neural correlates are more/less similar, and how does that pattern across the pairings compare to other datasets. There are other questions that one could ask with these data (and perhaps this group will in subsequent studies), which will provide additional information about the encoding; for example, how well does the population activity correlate with the kinematics, kinetics, and predicted sensory feedback that would accompany such movements in an able-bodied person?

      What this study shows is that the RDMs from these PPC Utah array data are most similar to motor cortical RDMs based on a prior fMRI study. It's innovative to compare effectors' representational similarity across different recording modalities, but this apparent similarity should be interpreted in light of several limitations: 1) the vastly different spatial scales (voxels spanning cm that average activity of millions of neurons each versus a few mm of cortex with sparse sampling of individual neurons, 2) the vastly different temporal scales (firing rates versus blood flow), 3) that dramatically different encoding schemes and dynamics could still result in the same RDMs. As currently written, the study does not adequately caveat the relatively superficial and narrow similarity being made between these data and the prior Ejaz et al (2015) sensorimotor cortex fMRI results before except for (some) exposition in the Discussion.

      Relatedly, the study would benefit from additional explanation for why the comparison is being made to able-bodied fMRI data, rather than similar intracortical neural recordings made in homologous areas of non-human primates (NHPs), which have been traditionally used as an animal model for vision-guided forelimb reaching. This group has an illustrious history of such macaque studies, which makes this omission more surprising.

      A second area in which the manuscript in its current form could better set the context for its reader is in how it introduces their motivating question of "do paralyzed BCI users need to learn a fundamentally new skillset, or can they leverage their pre-injury motor repertoire". Until the Discussion, there is almost no mention of the many previous human BCI studies where high performance movement decoding was possible based on asking participants to attempt to make arm or hand movements (to just list a small number of the many such studies: Hochberg et al 2006 and 2012, Collinger et al 2013, Gilja et al 2015, Bouton et al 2016, Ajiboye*, Willett* et al 2017; Brandman et al 2018; Willett et al 2020; Flesher et al 2021). This is important; while most of these past studies examined motor (and somatosensory) cortex and not PPC (though this group's prior Aflalo*, Kellis* et al 2015 study did!), they all did show that motor representations remain at least distinct enough between movements to allow for decoding; were qualitatively similar to the able-bodied animal studies upon which that body of work was build; and could be readily engaged by the user just by attempting/imagining a movement. Thus, there was a very strong expectation going into this present study that the result would be that there would be a resemblance to able-bodied motor representational similarity. While explicitly making this connection is a meaningful contribution to the literature by the present study (and so is comparing it to different areas' representational similarity), care should be taken not to overstate the novelty of retained motor encoding schemes in people with paralysis, given the extensive prior work.

      The final analyses in the manuscript are particularly interesting: they examine the representational structure as a function of a short sliding analysis window, which indicates that there is a more motoric representational structure at the start of the movement, followed by a more somatotopic structure. These analyses are a welcome expansion of the study scope to include the population dynamics, and provides clues as to the role of this activity / the computations this area is involved in throughout movement (e.g., the authors speculate the initial activity is an efference copy from motor cortex, and the later activity is a sensory-consequence model).

      An interesting result in this study is that the participant did not improve performance at the task (and that the neural representations of each finger did not change to become more separable by the decoder). This was despite ample room for improvement (the performance was below 90% accuracy across 5 possible choices), at least not over 4,016 trials. The authors provide several possible explanations for this in the Discussion. Another possibility is that the nature of the task impeded learning because feedback was delayed until the end of the 1.5 second attempted movement period (at which time the participant was presented with text reporting which finger's movement was decoded). This is a very different discrete-and-delayed paradigm from the continuous control used in prior NHP BCI studies that showed motor learning (e.g., Sadtler et al 2014 and follow-ups; Vyas et al 2018 and follow-up; Ganguly & Carmena 2009 and follow-ups). It is possible that having continuous visual feedback about the BCI effector is more similar to the natural motor system (where there is consistent visual, as well as proprioceptive and somatosensory feedback about movements), and thus better engages motor adaptation/learning mechanisms.

      Overall the study contributes to the state of knowledge about human PPC cortex and its neurophysiology even years after injury when a person attempts movements. The methods are sound, but are unlikely (in this reviewer's view) to be widely adopted by the community. Two specific contributions of this study are 1) that it provides an additional data point that motor representations are stable after injury, lowering the risk of BCI strategies based on PPC recording; and 2) that it starts the conversation about how to make deeper comparisons between able-bodied neural dynamics and those of people unable to make overt movements.

    1. Reviewer #3 (Public Review):

      Childhood acute myeloid leukemia (AML) is a heterogeneous disease with different outcomes for different patients, making identifying patients with different prognoses for clinical management. A variety of approaches have been used to stratify AML patients' risk, including molecular and clinical measurements to build prognostic risk scores. Previously, Chaudhary et al found that mitochondrial genome copy number per AML cell could stratify patients who would have good and poor outcomes and survival. This interesting finding suggested that mitochondrial amount and/or function alter AML disease course and suggested a further in-depth study of mitochondria in AML.

      Chaudhary and colleagues follow up their preliminary study on mitochondrial genome copy number in AML with this current study by looking if the expression of specific genes encoding mitochondrial components could provide further insight into AML prognosis. The authors collected childhood AML patient samples and grouped them based on mitochondrial genome copy number. They then performed transcriptomic analysis and identified a number of nuclear-encoded mitochondrial component genes whose expression was correlated or anticorrelated with mitochondrial genome copy number and this was confirmed with targeted analysis of identified transcripts in validation cohorts. Multivariate analysis was used to identify those genes whose expression was prognostic of patient outcome. This led to the identification of three mitochondrial genes (SDHC, CLIC1, SLC25A29) whose expression was used to build a multivariate risk model for childhood AML patients. The risk model based on the expression of these genes outperformed currently used ELN risk stratification and could be combined with ELN to increase prognostic power. Lastly, the authors used publically available data from adult AML patients and found that their risk score also had prognostic power in adult AML patients as well.

      Altogether, the work by Chaudhary and colleagues interestingly builds on their previous work and suggests that mitochondria may influence AML outcomes, and measuring mitochondrial parameters may help assess patient risk. Numerous exciting questions remain: what outputs of the mitochondria influence AML disease course and how? Why are some mitochondrial genes but not others correlated with mitochondrial DNA copy number in AML cells and how does this influence mitochondrial properties? Outside of predicting patient risk, can the mitochondrial phenotype of AML cells predict effective therapies? How does the mitochondrial risk model perform compared to and when utilized with other transcriptional-based risk stratification models proposed in the literature?

    1. Reviewer #3 (Public Review):

      In their previous work, the authors studied the problem of clonal life cycles evolution. Here they extended the previous work by developing a model that describes such evolution under the presence of competition between groups. The model is studied using a combination of analytical methods and numerical simulations. The results obtained are more biologically justifiable than those obtained in the linear model that neglects competition between groups.

      Strengths:

      - As is known from previous work, in a linear model (when the competition is absent), a typical outcome is an exponential growth in the number of groups of some life cycle, which can be considered as a natural limitation of the model. Obviously, this limitation is removed in the presented paper.

      - The authors provide analytical results for some special cases of the model and compare them with those obtained in the absence of competition. In the general case of the model, when analytical progress is impossible, the authors provide the results of extensive numerical simulations. All these results allow the authors to build a clear picture of the process under study.

      - The authors study the evolutionary stability of various life cycles. Specifically, it was shown that only binary fragmentation life cycles can be evolutionary stable strategies. This result holds in the linear model as well. In contrast to the linear model, more complex dynamics can be observed in the general case (like the existence of several evolutionary stable strategies).

      Overall, in my opinion, the model significantly contributes to our understanding of the evolution of clonal life cycles. Moreover, it illuminates to what extent are adequate the results of simple linear models in describing the processes under consideration.

    1. Reviewer #3 (Public Review):

      In this manuscript, the authors investigated the role of glutamine metabolism in chondrocytes and in the context of inflammation. Thus, they report that chondrocytes use glutamine for their energy production and anabolic functions. Moreover, they found that removal of glutamine resulted in metabolic reprogramming and decreased inflammatory response of chondrocytes. They attributed this anti-inflammatory response to decreased NF-κB activity. Moreover, the removal of glutamine promoted autophagy. This is a very interesting study and the vast majority of the conclusions are supported by strong data.

    1. Reviewer #3 (Public Review):

      The authors present a modular computational workflow for automated sample screening and collection of cryo-EM data and demonstrate its use for screening and 3D structure determination of human mitochondrial DNA polymerase as a test sample. Despite major advances in automation of microscope operation, optimising and screening sample conditions for the acquisition of high-quality data is still a laborious task that involves human input to navigate low-, medium- and high-magnification images to identify and select specimen areas amenable to high-resolution structure determination; and subjective tuning of parameters that can result in inefficient use of high-end cryo-TEM equipment. Fully automated methods for screening and data collection are therefore needed to meet the increasing demand for access and throughput of cryo-EM. Utilising deep-learning-based object detection algorithms, the authors show that their pre-trained models can effectively detect, classify, and rank regions (grid squares and holes) of interest based on established criteria such as contamination, support film integrity, and ice thickness. A challenge for any such method is the scarcity of annotated data reflecting the broad variety across the wide range of image and sample conditions in cryo-EM, and that selection of the "best" areas may vary by particle and sample preparation conditions. To mitigate this risk, the authors provide a web interface that allows re-training of the feature models and integrates on-the-fly assessment of data quality and adjustment of data collection parameters. As such, the presented pipeline and related approaches can become a useful addition to existing automation software for cryo-EM data collection, in multi-user environments such as cryo-EM facilities. Such approaches will best strive if software and models are openly available to the cryo-EM community so that annotated data can be added or customised and the quality of the prediction methods can improve over time.

    1. Reviewer #3 (Public Review):

      In general, I find this to be an experimentally and analytically sound paper. The observation that rate information is preserved in hippocampal replay is hinted at in previous work, but to my knowledge, has not yet been explicitly quantified as the authors have done here. Thus, this work is novel and, in my opinion, an important contribution to our understanding of hippocampal network function.

      The large number of control analyses strongly support the core finding of this work. I feel that the authors have very convincingly demonstrated that rate information is represented along with spatial information in replay.

      While I can think of many suggestions to follow up on this work, I have no major concerns regarding the experiments, analyses, or interpretation of the manuscript.

    1. Reviewer #3 (Public Review):

      The TRPV1 receptor channel is primarily localised to sensory nerves as well as other non-neuronal tissues. It has been known for some time that TRPV1 has a role in the regulation of body temperature, as TRPV1 antagonists, being developed as analgesics, cause hyperthermia. There is a need for further mechanistic information, as the present drug discovery programme has been delayed by the inability of scientists to develop TRPV1 analgesics that act without temperature-related side effects. This manuscript is designed to investigate whether sensory nerves or smooth muscle cells are included in the mechanisms, through the study of tissue specific genetically modified mice.

      This is a highly readable and concise manuscript with a relatively simple and clear take home message that advances current knowledge. However, at times the information could be more fully given.

    1. Reviewer #3 (Public Review):

      This work seeks to identify a common factor governing priority effects, including mechanism, condition, evolution, and functional consequences. It is suggested that environmental pH is the main factor that explains various aspects of priority effects across levels of biological organization. Building upon this well-studied nectar microbiome system, it is suggested that pH-mediated priority effects give rise to bacterial and yeast dominance as alternative community states. Furthermore, pH determines both the strengths and limits of priority effects through rapid evolution, with functional consequences for the host plant's reproduction. These data contribute to ongoing discussions of deterministic and stochastic drivers of community assembly processes.

      Strengths:

      Provides multiple lines of field and laboratory evidence to show that pH is the main factor shaping priority effects in the nectar microbiome. Field surveys characterize the distribution of microbial communities with flowers frequently dominated by either bacteria or yeast, suggesting that inhibitory priority effects explain these patterns. Microcosm experiments showed that A. nectaris (bacteria) showed negative inhibitory priority effects against M. reukaffi (yeast). Furthermore, high densities of bacteria were correlated with lower pH potentially due to bacteria-induced reduction in nectar pH. Experimental evolution showed that yeast evolved in low-pH and bacteria-conditioned treatments were less affected by priority effects as compared to ancestral yeast populations. This potentially explains the variation of bacteria-dominated flowers observed in the field, as yeast rapidly evolves resistance to bacterial priority effects. Genome sequencing further reveals that phenotypic changes in low-pH and bacteria-conditioned nectar treatments corresponded to genomic variation. Lastly, a field experiment showed that low nectar pH reduced flower visitation by hummingbirds. pH not only affected microbial priority effects but also has functional consequences for host plants.

      Weaknesses:

      The conclusions of this paper are generally well-supported by the data, but some aspects of the experiments and analysis need to be clarified and expanded.

      The authors imply that in their field surveys flowers were frequently dominated by bacteria or yeast, but rarely together. The authors argue that the distributional patterns of bacteria and yeast are therefore indicative of alternative states. In each of the 12 sites, 96 flowers were sampled for nectar microbes. However, it's unclear to what degree the spatial proximity of flowers within each of the sampled sites biased the observed distribution patterns. Furthermore, seasonal patterns may also influence microbial distribution patterns, especially in the case of co-dominated flowers. Temperature and moisture might influence the dominance patterns of bacteria and yeast.

      The authors exposed yeast to nectar treatments varying in pH levels. Using experimental evolution approaches, the authors determined that yeast grown in low pH nectar treatments were more resistant to priority effects by bacteria. The metric used to determine the bacteria's priority effect strength on yeast does not seem to take into account factors that limit growth, such as the environmental carrying capacity. In addition, yeast evolves in normal (pH =6) and low pH (3) nectar treatments, but it's unclear how resistance differs across a range of pH levels (ranging from low to high pH) and affects the cost of yeast resistance to bacteria priority effects. The cost of resistance may influence yeast life-history traits.

  2. Jul 2022
    1. e moment of transition of the Internet—from mediating information to mediating distributeddirect governance in the sense of self-organization.
      • With proper design, the internet can play a more proactive role
      • From passive to active, sensemaking to action
      • Cosmolocal production: https://clreader.net
      • Web 3 technology
      • Indyweb
    1. just to give you a feel for how powerful these systems are just think of the bitcoin energy consumption and realize that that 00:09:48 just drops out of two components in bitcoin one is the block reward impact evaluator and two the price of bitcoin so those two things yield this tremendous energy 00:10:00 consum consuming system this was kind of an accident this was a an accident of nobody quite intended this this device to um consume this this amount of energy and waste this amount of energy uh but 00:10:13 this gives you a sense of the power of these these uh systems first off we should fix this and you know get out get to uh better systems that that actually uh make this this um energy use uh useful 00:10:25 uh but this i use as an example to give you a sense of like the level of power that comes from these incentive structures and their operation at scale in falcon we're very familiar with these kinds of structures we use the same component and we've gotten a feel for how powerful 00:10:38 this stuff is um in just a couple of years we ended up organizing the build out of a massive hardware infrastructure for providing storage to the world um with again just using one 00:10:51 core incentive structure a block reward uh so all of this makes me really really hopeful um that we'll be able to build um these kinds of incentive structures that can scale to solve extremely large planetary scale 00:11:03 problems um by designing incentive structures and structures warping the incentive fields and getting us to little by little problem by problem scale by scale um solve challenges 00:11:17 and so i think i greatly encourage you if you aren't already in this uh world to try it out to try creating some smart contracts and deploying them um to try uh working with other projects and so on 00:11:29 to get a feel for how powerful these these systems are um i i'm very hopeful that things like this will have a huge impact on planetary scale problems like uh climate change um i've become very hopeful that 00:11:41 these systems will let us coordinate massive action again millions of people billions of people whole industries by letting us have the full power of law and economics and so on in a fully 00:11:55 programmable environment i'm also very hopeful that we can get to accelerate science and technology development by using these kinds of structures to create instruments to incentivize areas of the innovation chasm that are 00:12:08 underserved areas where it's extremely difficult to get funding for certain projects or where it's extremely difficult to get long-term rewards or long-term success many of you have probably heard me talk 00:12:21 about this science and technology translation problem and the lack of incentive structures in that in that period in the castle in the middle and i think a lot of that just comes from the lack of reward structures there that make it impossible for 00:12:34 groups building groups building building projects there to raise capital um because there's no good incentive for capital uh to to deploy there so uh what brought us to so knowing all 00:12:46 of this knowing that this is a critical century knowing that um this critical decade and year um and knowing that crypticon is extremely powerful um why are we here why are we in funding commons so we thought about this problem last year and 00:12:59 we saw that the scale of problem of um of blockchains and the kind of rapid pace of development in industry and the emergence of things like defy and dials and nfts and so on 00:13:10 and especially the the broad adoption by hundreds of thousands of people or millions of people of these tools gave us a very promising um landscape to be able to solve these kinds of problems 00:13:23 and so we have the potential to solve all these massive coordination problems but we're lacking good mechanisms we need way better governance structures we need way better funding mechanisms and uh and so on we need to study these things with much 00:13:36 deeper theory and much deeper experimental analysis and so on

      Bitcoin, in spite of its unintended consequences, does demonstrate the power and potential of these kinds of systems to scale.

    1. so let's suppose let's suppose your listeners are with me and you know we kind of agree like okay yes transformation's necessary and uh again i want to emphasize i'm not talking about reform i'm not talking 00:58:59 about a softer better capitalism i'm not talking about you know improved voter registration or like any of those things i'm talking about de novo starting over from scratch what might be 00:59:13 best and if it turns out that the old systems were better than anything that humanity can come up with well then you know that's the answer but i can't imagine that's true because the old systems were never designed in any kind of 00:59:25 you know thoughtful science driven [Music] you know process to to to test to explore and to come up with fitness like what is the you know we don't even have a fitness for our current society 00:59:39 much less of fitness for societal designs i mean we have the gdp but that's a terrible terrible limited fitness metric 00:59:51 okay so suppose you're with me suppose we're we're on board we we want to do this de novo design thing where do we start what's the what's what where do we even get off the 01:00:03 ground on this and i suggest that the way to do it is through first address worldview from world view once we understand what the world view is 01:00:15 what a reasonable useful world view will be for this project then then purpose derives worldview begets purpose once you understand what it is you want 01:00:28 what you value what do you value once you understand what you value then you can say well i value a and therefore the purpose is to 01:00:39 have a manifest in society for example so once you have purpose then you can think about what metrics how would you measure whether are you so 01:00:53 here's a new design is it fit for purpose does it do does it fulfill its purpose you know that's the question and then metrics go with some kind of fitness evaluation 01:01:05 and then finally last of all of those would be the design okay we know what we know what we value we know what this thing is supposed to do we know what the purpose is we know that attractor is supposed to you know plow the ground or something we 01:01:18 know what this is supposed to do we know how to measure success and uh now finally then let's talk about design what are the what are the you know the specifics and mechanics and 01:01:31 how does that happen and the the series is really kind of laid out this way the first paper really talks about world view and purpose the second paper talks about the you know the more the mechanics of things 01:01:44 like viability how would you make this thing viable things like that and then the very last paper that's titled the subtitle design okay so uh that's how we uh and 01:01:56 and maybe i will just mention here that i put metrics before design because we might have some ideas uh getting back to that preference factor we might have some ideas like we would like people not to die at 01:02:08 30 you know we'd like people to mostly live to a ripe old age and have you know enough water water to drink and food to eat and all that kind of stuff so uh you know what kind of design once 01:02:20 now that we have metrics to measure that kind of stuff longevity and nutrition and things what kind of designs would help us to reach those targets you know so that's one reason why design 01:02:31 why metrics comes before design okay

      Process flow: Worldview, purpose, metric and finally design

      Paper 1: Worldview and purpose Paper 2: practical implementation Paper 3: Design

  3. Jun 2022
  4. May 2022
  5. Apr 2022
    1. # Input Input: 123, Output: Input: 121, Output: Input: 111, Output: Input: 123454321, Output: Input 123123, Output: # Instruction Output true if input is a palindrome # Output Input: 123, Output: false Input: 121, Output: true Input: 111, Output: true Input: 123454321, Output: true Input 123123, Output: false

      Example of using GPT-3 for programming

  6. Mar 2022
  7. learn-us-east-1-prod-fleet02-xythos.content.blackboardcdn.com learn-us-east-1-prod-fleet02-xythos.content.blackboardcdn.com
    1. fighting ability was one way that this prayer was answered for some

      fighting and honor and protection

    2. Most bondsmen would have to mask their honor when confronted withaffronts and wait until a potential window of opportunity to seek redress; oth-ers displayed their honor at times by resisting dishonor

      honor by resisting dishonor

    3. the code of honor among bondsmen assumed a “sacredness,”and transgressors would, among other retributions, have “their names cast outas evil from among their brethren, and being subjected to scorn, and perhapspersonal violence.”

      honor

    4. In Africa fighters often exhibited their power on behalf of the enslavedcommunity in the enforcement of honor.

      enforcement

    5. Others commanded respect fortheir demonstrated skill in physical contests such as climbing poles, wrestling,or knocking and kicking. Through these various forms of display, enslavedAfricans and their descendants exclaimed their individual worth and honor.The desire to seek such communal honor was clearly strong

      honor

    6. an enslaved woman could gain honor in the eyes of the communityfor her ability to sing, hypnotize the community with engaging stories, or dancewith grace

      honor for all regardless of gender

    7. black drivers who felt compelled by the honor code not to carry out orderedwhipping if the plantation owner was not immediately present.2

      how far honor goes

    8. loyalty while enslaved

      concept

    9. enslaved showed this respect toone another by hiding and feeding runaways and refusing to betray otherbondsmen

      how remained honorable

    10. honor was loyalty to fellowbondsmen.

      honor

    11. loyalty to peers, personal displays, vengeance, and resistance to dishonor

      .

    12. honor system of Africansand their descendants in North America was most clearly exhibited through

      .

    13. Europeans and their descendants in North America did not always recog-nize this bonded honor code, but southern elites lived by their own reflexivehonor system that led to violent gouging matches and later duels.2

      white ppl are dumb

    14. Enslaved Africans carried strong concepts of honor to North America. As wehave seen, the pastoral Angolans held a tradition of reflexive honor in whichaffronts to honor were settled in stick fights.

      honor

  8. ivanov-petrov.livejournal.com ivanov-petrov.livejournal.com
    1. Есть маргинальная теория, на стыке психологии и философии, активно эксплуатирующая принцип 3+1. Теория предлагает рассматривать каждый аспект человеческой жизни как адаптацию ...Когда удаётся сформулировать, что именно в природе человека не совпадает с природой окружающего мира, то почти на каждую формулировку приходится 1+3 стратегии адаптации (одна прямая и 3 косвенных)...Для человека довольно естественно полагать себя бессмертным (в том или ином смысле) или, как минимум, полагать что он должен быть связан с чем-то не подверженным разрушению. В то же время, наблюдаемый бренный мир постоянно и непрерывно движется к распаду. ...Можно кратко обозначить начальные условия адаптации: мы пытаемся ощутить свою бессмертную природу в умирающем бренном мире. Психологически, такого рода адаптация регулируется чувством ничтожности. ...Если чувство собственной ничтожности невыносимо, значит бренный мир хорошенько нам врезал, разрушив ту часть нас, которую мы считали незыблемой.По теории, должны быть 4 стратегии, как адаптировать знание/представление о своей бессмертной природе к наблюдаемому бренному миру. Прямая стратегия - ориентация на вечное. Попытаться связать свою жизнь с тем что выходит за пределы времени, найти в себе то что принадлежит вечности. Например, ощутить себя частью замысла творца, найти смысл жизни и т.п. Прямая стратегия - стратегия независимости, она почти всегда игнорирует природу наблюдаемого мира, т.е. в данном случае - время. Три оставшихся стратегии, по теории, должны быть вспомогательными и уж они ничего не игнорируют. Стратегия ориентации на прошлое борется с чувством ничтожности через поиск артефактов, прошедших проверку временем. Связь с семьёй, устойчивые черты характера, проверенные временем таланты, память о незабываемых событиях, написанные статьи. Пока всё это живо, жив и я и чуть менее ничтожен в мире, где время всё разрушает. Стратегия ориентации на настоящее борется с чувством ничтожности через поиск лучшего места в бренном мире. Тот кто прямо сейчас находится в лучшем для себя месте и в лучших условиях, ощущает себя менее ничтожным, чем все остальные. Стратегия ориентация на будущее борется с ничтожностью с помощью понимания логики времени, видения текущих процессов. Тот кто знает, где мир окажется завтра, более живуч и утонет последним.Получается красиво: 3+1 (прошлое/кто я?, настоящее/где я?, будущее/куда я иду?) и вечность/зачем я?
  9. Feb 2022
  10. openlab.citytech.cuny.edu openlab.citytech.cuny.edu
    1. But it isn’t. This is because over such a long period a message can easily be distorted or altered without this being in any way intended. (This distortion or alteration in the meaning or method of transmission of a message, whether intended or not, is called “noise.”) Languages, both written and spoken, always change. The meanings of symbols are often lost in the passage of time. In fact, most messages are bound so closely to a particular period and place that even a short time later they cannot be understood. Therefore, ensuring that a message created now can be decoded by future generations is highly problematic.

      Can symbol that represents one thing change over a long period of time to mean something different?

    2. ea. It is only because there is already a well-established connection in our minds between the appearance of an apple and the idea of temptation that this fruit is used in the picture. It is this connection that makes the picture successful in terms of communicatio

      Why was the apple chosen as the representation of temptation?

    3. semiotician,

      A Theory of signs and symbols that deals especially with there function in both artificially constructed and natural languages.

  11. Jan 2022
    1. Des initiatives pour protéger ces espaces :

      Arg3: Malgré les risques environnementaux qui pèsent sur les EM, il existe des initiatives pour protéger ces espaces

      • Réduction des émissions de CO2 GAS + niveau CO2 atm + température ++ océans = phytoplanctons moins utiles à l'homme Absorber 30% du CO2 généré par l'homme Produire 50% oxygène = indispensables pour la vie humaine sur terre.
    2. La lutte contre les trafics illégaux

      Arg3: Les Etats tentent également de lutter contre les trafics illégaux

      • Lutte contre la pêche illicite Selon FAO = 15 et 20 % des prises => 23 Milliards $ /an Moins de préservation du stock renouvelable = surpêche Concurrence déloyale = pecheurs + respect quotas

      • Lutte contre le trafic de cocaïne 2017 - 2019: Cocaïne saisie à bord d'embarcations commerciales x3 = 73 tonnes Moyens ? Sous marins artisanaux, Ou ? Antilles = plaque tournante Quelles saisies ? 3 tonnes sous marins par police espagnole en 2019

      • Lutte contre le trafic des déchets Cout traitement + législation contraignante = Etats exportent leurs déchets / filières illégales ==> Pays d'Asie et d'Afrique: ++ déchets électroniques Malaisie => FR: 43 conteneurs de plastique illégaux

    3. Des espaces qui suscitent des litiges et des contentieux

      Arg3: Les EM sont au coeur de tensions géopolitiques entre les Etats qui se disputent l'accès aux ressources halieutiques, hauturières et aux routes maritimes

      • Mer de Chine méridionale Chine // Philippines, Vietnam, Brunei, Indonésie, Malaison "langue de boeuf" => Archipel des Spratleys + Îles Paracels Zone de trafic CMM Territorialisation , militarisation des EM Mars 2020: percussion bateau de pêche vietnamien

      • Mer de Chine Orientale Chine // Japon Îles Senkaku et Diaoyu COVID19: Liaoning traverse ZEE jap

      • Mer méditerranée Turquie // Grèce // Chypre // Israël // Liban EM triangulaire de 850km² = réserves de gaz ?

    4. Les ressources énergétiques

      Arg3: les ressources énergétiques sont également exploitées dans les Mers et les Océans

      • les hydrocarbures 30% hydrocarbures proviennent de gisements offshore Mer du Nord, Mer Caspienne, Golfe de Guinée, Golfe Arabo-persique, Mer de Chine méridionale

      espaces inexploités: conditions extrêmes (Arctique), fonds marins profonds = ++ pression (Brésil qui se lance dans l'exploitation d'hydrocarbures au dela du plateau continental)

      • les énergies renouvelables off shore Usines marémotrices: UM de la Rance (Côtes d'Armor, FR) Parcs éoliens off shore: projets aux îles de Lérons, Europe = 1er prod mondial électricité = 5000 éoliennes off shore (Mer du Nord ++)

      • les avancées scientifiques possibles Bathymétrie est mal connue = couts ++ 90% des espèces marines resteraient à découvrir

    5. Argument 3 : Les routes maritimes, les points de passage stratégiques et les goulets d’étranglement : des espaces maritimes vitaux pour le commerce maritime

      Arg3: les enjeux vitaux des chokes points pour l'économie mondialisée et le CM Connecter espaces de prod°/conso° Espaces maritimes très réduits concentrent trafic maritime:

      • Canaux; Suez, Panama
      • Détroit, Ormuz, Gibraltar, Bab el Manbed, Bering, Malacca
      • Caps: Bonne espérance, Horn

      Détroit de Malacca selon Institut Supérieur d'économie marine (2017) 14M barils / jours Port Klang (Malaisie) = 12e port à conteneurs mondial "Dilemme de Malacca" selon Hu Jintao 20 - 25% du trafic mondial / an

      Dépendance = ouverture permanente des passages stratégiques Mauvaise situations: insécurité, piraterie, conflits, tensions géopolitiques sinon = perturber approvisionnement marchandises + matières premières = - économie mondiale EX: 1967 -> 1974 = pas Canal de Suez (G6jours) alternative = Cap de Bonne Espérance (+ temps, +argent)

  12. Dec 2021
    1. RRID:ZFIN_ZDB-GENO-071217-3

      DOI: 10.7554/eLife.72345

      Resource: (ZFIN Cat# ZDB-GENO-071217-3,RRID:ZFIN_ZDB-GENO-071217-3)

      Curator: @scibot

      SciCrunch record: RRID:ZFIN_ZDB-GENO-071217-3


      What is this?

    1. Second Amendment freedom of expression?

      it should be regarding the first amendment not second!

  13. Nov 2021
    1. painted an American flag on his bare chest, but painted it upside down.

      incorrect- the act being charged is "Unfurled the glad, doused it with kerosene and set it on fire"

    1. El factor tiempo de trabajo está también muy relacionado con la variabilidad de la presión de inyección, ya que a medida que incrementa el tiempo de operación de un motor, se incrementa el desgaste de las piezas, siendo agravado el sistema de alimentación por la variación de la calidad del combustible

      También depende del factor de cuanto uso se le ha dado a ese motor, no solo por el incremento de desgaste significa que va a bajar su calidad.

    1. a stoichiometry of approximately one complex molecule per actin monomer

      This seems like an unreasonably high stoichiometry of Arp2/3 complexes per actin subunit; we now know that each Arp2/3 complex covers a few subunits, so there shouldn't be enough room on the filament to fit 1:1 Arp2/3 complex/actin

  14. Oct 2021
    1. List only the first author’s name followed by “et al.” in every citation, even the first, unless doing so would create ambiguity between different sources.

      APA 7 3 or more authors

    1. There will be three billion gamers by next year, according to a Newzoo study. And as Loftus puts it: “People are going to need to wear something.”

      THIS is it - web 3 is making consumers mutiplicitous - opens marketts WITHIN games, subworlds that can be exploited / marketed to / fashion trends will sweep games, online subcultures (maybe) - people have markeable personas on and off the web, new context for targeted advertising / commerce.

      Will cannabalize physical economies?

      Accessorize for a zoom meeting - digital suits, etc digital costumes. Something to wear at digital concerts, in games; your Perona will not be birthed into the metaverse clothed, accessorized...

      Assets will be portable across platforms.

    1. the power to destroy may defeat and render useless the power to create

      Is this the foundational argument for the Supremacy Clause? For this example, does this mean if the states had the power to influence federal programs or policies, that the powers delegated to the federal government would be redundantly delegated?

    2. is not supreme.

      When do state laws take effect over federal laws? How do you know when which is supreme? or vice versa?

    3. But if the full application of this argument could be admitted, it might bring into question the right of Congress to tax the State banks, and could not prove the rights of the States to tax the Bank of the United States.

      Based on the relationship between State, banks, and General Government, is this suggesting a contradiction or non mutual relationship between the 3 in this line of argument?

    4. Its means are adequate to its ends, and on those means alone was it expected to rely for the accomplishment of its ends.

      This whole phrase is really confusing me? I'm not able to even figure out what any of the parts mean, could anybody help me out?

    5. but by people over whom they claim no control.

      Is this suggesting that if States were allowed to tax the Federal Government, would States hold power and authority over citizens outside of their state? Would State laws apply universally?

    6. This is, we think, the unavoidable consequence of that supremacy which the Constitution has declared.

      A lot of this argument seems centered around the idea that the people, via its representatives, declared the Constitution has supreme power over states. In this, a State (and by extension, representatives of the people) is arguing the apparent supremacy of the federal gov't over the state, doesn't this contradict the argument of the Supreme Court a bit, that the will of the people was for a federal gov't to hold supreme over state?

    7. The powers of the General Government, it has been said, are delegated by the States, who alone are truly sovereign, and must be exercised in subordination to the States, who alone possess supreme dominion.

      Does Maryland grapple with the idea that the sovereignty and power of the states comes from the people in its argument that the Constitution receives its power from the states, as opposed to the people?

    8. we shall find it capable of changing totally the character of that instrument

      I don't understand what this is saying? So on the basis of Marylands contends it changes the meaning of what the Bank means in the constitution?? I'm not sure if I even read it correctly the end of the sentence isn't making sense to me. Changes the character of what instrument? Constitution?

    9. Taxation, it is said, does not necessarily and unavoidably destroy.

      Taxation seems to be a big pinpoint of this argument. In history we have seen many problems with "taxation without representation" or misuse of taxing in this case, but we also see problems today with people not agreeing with where the tax money goes, or especially problems with getting tax returns. Do you think taxation is going to continue being a problem?

    10. Would the people of any one State trust those of another with a power to control the most insignificant operations of their State Government?

      This question is more a thought for questions. Do you think that this idea of one government have power over another government issues still stand in to days modern world? or do you think that states and governments the the US are more lacs about this issues then they where in 1819?

    11. which another Government may furnish or withhold

      Is 'another government' directly referring to the state vs. the national government?

    12. But is this a case of confidence?

      What constitutes a case of confidence? Is Marshall saying here that the national and state governments need to just have confidence in one another that there will be no abuse of power from either end? When does the Court decide a case is to be considered a case of confidence?

    13. But the two cases are not on the same reason.

      Kind of seperate, but do federal buildings pay taxes to the state they are in? Or to the government? Or do they pay at all? If they dont does that mean that the state tax payer does?

    14. unanimously of opinion

      In the Epstein text, it says that one of the seven Supreme Court Justices, Thomas Todd, did not participate in the decision. So it was unanimous, but only among 6 of the 7. I wonder why Todd didn't participate? Does anyone know from the text or other history?

    15. We shall find it capable of arresting all the measures of the Government, and of prostrating it at the foot of the States.

      I feel like this is a tad dramatic. How would allowing Maryland to tax a government institution arrest "all the measures of the Government"? I understand that taxing the bank would likely lead to the closing of that bank - but how would it interrupt the rest of our governence?

    1. NFTs are compatible with anything built using Ethereum. An NFT ticket for an event can be traded on every Ethereum marketplace, for an entirely different NFT. You could trade a piece of art for a ticket!

      There - opens up GIGANTIC barter economy possibilities - will shut out old middle men & create new ones - swap airline tickets / hotel reservations for concert tickets or memorabilia

    1. Truman's action can be upheld as an exercise of the president's inherent military power as commander-in-chief.

      incorrect: The Court held that the President's military power as Commander in Chief of the Armed Forces did not extend to labor disputes.

    1. We do not need images here. you can use some kind of icon if you wish. But this is largely text. Also FYI this section might need a headline. Such as summary overview - tbd.

    1. It is also not entirely unworthy of observation, that in declaring what shall be the supreme law of the land, the constitution itself is first mentioned; and not the laws of the United States generally, but those only which shall be made in pursuance of the constitution, have that rank.

      Now that Marshall observes the supreme law of the land to be the constitution, this makes me wonder how the Judiciary Act of 1789 was passed when it altered the original jurisdiction that was written in the constitution. Did the creators of the this act not consult or care about the constitution?

  15. Sep 2021
    1. Why does a judge swear to discharge his duties agreeably to the constitution of the United States, if that constitution forms no rule for his government? If it is closed upon him, and cannot be inspected by him?

      This concludes Marshall's habit of asking questions that he proceeds to answer. Are many modern day decisions written similarly? Or is this style more suited to an early justice seeking to define the role of the court, including the types of questions a Justice should be asking and answering?

    2. If congress remains at liberty to give this court appellate jurisdiction, where the constitution has declared their jurisdiction shall be original; and original jurisdiction where the constitution has declared it shall be appellate; the distribution of jurisdiction, made in the constitution, is form without substance.

      Okay help me clarify this. In this phrasing saying that if Congress gives appellate jurisdiction over the constitution witch already holds original jurisdiction than that new law or rule makes no sense?

    3. mandamus should be used for that purpose, that will must be obeyed. This is true, yet the jurisdiction must be appellate, not original.

      So a mandamus can only be applied to Appellate jurisdiction and not Original? Or can it be applied to both if met with the "specificity" of the original jurisdiction requirements?

    4. no bill of attainder or ex post facto law

      I realize this is just an example he's using to prove his point, that every word of the constitution is important and that the constitution should trump other laws. However, I've never heard of either of these - A "bill of attainder" or an "ex post facto" law. Does anyone know what these are?

    5. If, however, such a bill should be passed and a person should be prosecuted under it; must the court condemn to death those victims whom the constitution endeavors to preserve?

      I'm a little confused on how this analogy fits in. Is this meaning that the bill passed should be enforced by the courts? If this is true how exactly does this fit in the argument?

    6. If any other construction would render the clause inoperative, that is an additional reason for rejecting such other construction, and for adhering to their obvious meaning.

      I do not understand how this statement relates to what was said before. If I'm correct, the previous statements was suggesting that the supreme and inferior courts have certain jurisdiction. Are they saying that how jurisdiction is determined may change over time?

    7. Neither is it necessary in such a case as this, to enable the court to exercise its appellate jurisdiction.

      I thought the whole point of this case was to review laws or precedents within the constitution and deem whether or not they were truly viable. Doesn't appellate jurisdiction become necessary then? A higher court overturning a lower courts decision?

    8. It is then the opinion of the court,

      How can a court's opinion change? When there are different people on the court would that maybe produce a different outcome? How would you be able to be sure that things are standard?

    9. he power remains to the legislature, to assign original jurisdiction to that court in other cases than those specified in the article which has been recited; provided those cases belong to the judicial power of the United States.

      I am confused on how the legislature fits into the court's original jurisdiction. Did the legislature have to approve each of the cases that the supreme court took? Why only for original jurisdiction and not appellate jurisdiction as well? Does this still apply today?

    10. to issue writs of mandamus to public officers, appears not to be warranted by the constitution

      Where does the issue writs of mandamus come from then if not the constitution? I thought that the way judicial courts act were all centered around the constitutional law. But the way this is worded, it appears that mandamus is not in reference to the constitution.

    11. Here the language of the constitution is addressed especially to the courts. It prescribes, directly for them, a rule of evidence not to be departed from. If the legislature should change that rule, and declare one witness, or a confession out of court, sufficient for conviction, must the constitutional principle yield to the legislative act?

      I'm curious as to how the writers of the Constitution had not considered that something similar could occur? Why did the writers not introduce some sort of specific method where one of the branches could declare an action of another unconstitutional?

    1. Voluntary Cessation Doctrine,

      I looked up the Voluntary Cessation Doctrine, but I am still unsure what it means and how it pertains to this case? I wish they would have elaborated more on it. I could be mistaken, but I believe the Doctrine deals with exceptions to mootness, however, I thought Justice Breyer said this case was not moot.

    2. Locke v. Davey

      Does Lockey vs Davey involve the qustion of scholarship (of religious schools) provided from government money? Thats what I'm gathering but I'm not sure. Not familiar with the case but before I look it up I'm guessing it has to do with government funded school scholarships secular vs non secular?

    3. Well -- well, for -- if the political winds change, we have -- we have this policy by Facebook or press release. So it can easily be changed back if political --

      How often does social media play a part into political bias? How are judges or trial members able to keep their rulings separate from the bias they're hearing in the news or headlines?

    4. David A Cortman

      He doesn't really answer the justices question of how he doesn't see the other way of questioning as discrimination IN FAVOR of the church against other non religious people which I think is sort of telling and again why I think justice sotomayor is one of the dissenting judges. One question I have is whether or not there actually is anything in the constitution that protects discrimination in favor of religion? I always hear about it the other way around and I remember in one instance not long ago about a christian baker who refused to bake a wedding cake for a gay couple based on the argument that it violates his ability to practice his religious beliefs. The court sided with him, which to me is discrimination in favor of "religious beliefs" that was ruled by the supreme courts as justified and constitutional.

    5. There's also entanglement.

      Having no prior knowledge of the Establishment Clause, I believe I've been able to glean a little of what it might say from the course of listening to this case. The application of it seems to be broken into two halves of conditionality, "endorsement" and "entanglement." Does anyone on the thread have a definition of what these two conditions mean?

    6. Locke, right? Locke drew a distinction between assistance for devotional, theological education and scholarship and others.

      This mention of Locke has been used numerous times throughout this conversation, and I have yet to understand where the meaning of this is being drawn from. Are they referring to something John Locke wrote? Is this the name of something or someone I may have missed?

    1. ZFIN: ZDB-ALT-110503-3

      DOI: 10.1016/j.cub.2021.08.049

      Resource: (ZFIN Cat# ZDB-ALT-110503-3,RRID:ZFIN_ZDB-ALT-110503-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-110503-3


      What is this?

    2. ZFIN: ZDB-ALT-120320-3

      DOI: 10.1016/j.cub.2021.08.049

      Resource: (ZFIN Cat# ZDB-ALT-120320-3,RRID:ZFIN_ZDB-ALT-120320-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-120320-3


      What is this?

    3. ZFIN: ZDB-ALT-071129-3

      DOI: 10.1016/j.cub.2021.08.049

      Resource: (ZFIN Cat# ZDB-ALT-071129-3,RRID:ZFIN_ZDB-ALT-071129-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-071129-3


      What is this?

    1. polyphonic

      polyphonic: style of musical composition employing two or more simultaneous but relatively independent melodic lines

      merriam

    2. primordial

      primordial: existing in or persisting from the beginning (as of a solar system or universe)

      merriam

    1. Dampness and mould growth were also a feature of some houses on the Whiteway and Twerton council

      dampness of homes in council estates in Bath. research for community advocacy. Collective action example.

    Tags

    Annotators

    1. he teacher proceeded to belittle everyone from German Eva, who hated laziness, to Japanese Yukari, who lovedpaintbrushes and soap. Italian, Thai, Dutch, Korean, Chinese--we all left class foolishly believing that the worstwas over. We didn't know it then, but the coming months would teach us what it is like to spend time in thepresence of a wild animal. We soon learned to dodge chalk and to cover our heads and stomachs whenever sheapproached us with a question. She hadn't yet punched anyone, but it seemed wise to prepare ourselves againstthe inevitable.

      he is transitioning from what he is going through to what he went through through the class. teacher seems pretty mean towards the students and a little bit aggressive

    2. When called upon, I delivered an effortless list of things I detest: blood sausage, intestinal pâté, brain pudding.I'd learned these words the hard way. Having given it some thought, I then declared my love for IBM typewriters,the French word for "bruise," and my electric oor waxer. It was a short list, but still I managed to mispronounceIBM and afford the wrong gender to both the oor waxer and the typewriter. Her reaction led me to believe thatthese mistakes were capital crimes in the country of France.

      he thought he was doing well until he mispronounced ibm and learns that it was a mistake he shouldn't of made because of how the teacher was ridiculing every single student he was confused as to why the teacher was referring to objects as genders it just didn't make sense to him

    3. I remind myself that I am now a full-grown man. No one will ever again card me for a drink or demand that Iweave a oor mat out of newspapers. At my age, a reasonable person should have completed his sentence in theprison of the nervous and the insecure--isn't that the great promise of adulthood? I can't help but think that,somewhere along the way, I made a wrong turn. My fears have not vanished. Rather, they have seasoned andmultiplied with age. I am now twice as frightened as I was when, at the age of twenty, I allowed a failed nursingstudent to inject me with a horse tranquilizer, and eight times more anxious than I was the day my kindergartenteacher pried my ngers off my mother's ankle and led me screaming toward my desk. "You'll get used to it," thewoman had said.

      feeling very scared. seems like he is regretting it a little bit?

  16. Aug 2021
    1. RRID:ZFIN_ZDB-ALT-140521-3

      DOI: 10.7554/eLife.44431

      Resource: (ZFIN Cat# ZDB-ALT-140521-3,RRID:ZFIN_ZDB-ALT-140521-3)

      Curator: @scibot

      SciCrunch record: RRID:ZFIN_ZDB-ALT-140521-3


      What is this?

    1. RRID:_ZFIN_ZDB-GENO-090923-3

      DOI: 10.7554/eLife.38911

      Resource: (ZFIN Cat# ZDB-GENO-090923-3,RRID:ZFIN_ZDB-GENO-090923-3)

      Curator: @scibot

      SciCrunch record: RRID:ZFIN_ZDB-GENO-090923-3


      What is this?

    1. RRID:ZFIN_ZDB-ALT-071109-3

      DOI: 10.7554/eLife.68755

      Resource: (ZFIN Cat# ZDB-ALT-071109-3,RRID:ZFIN_ZDB-ALT-071109-3)

      Curator: @scibot

      SciCrunch record: RRID:ZFIN_ZDB-ALT-071109-3


      What is this?

  17. Jul 2021
    1. RRID:ZFIN_ZDB-GENO-170619-3

      DOI: 10.7554/eLife.35796

      Resource: (ZFIN Cat# ZDB-GENO-170619-3,RRID:ZFIN_ZDB-GENO-170619-3)

      Curator: @evieth

      SciCrunch record: RRID:ZFIN_ZDB-GENO-170619-3


      What is this?

    1. Those are some typical metadata elements: Title and description, Tags and categories, Who created and when, Who last modified and when, Who can access or update.

      This list makes sense based on the definition of metadata above in the article saying that it helps organize, find and understand data. I would expect these elements to be a part of metadata because they all give information as to what you are looking at and who created it.

    2. Metadata is simply data about data. It means it is a description and context of the data. It helps to organize, find and understand data.

      The word metadata sounded way more advanced than my skill level in computers. I didn't really know what the word metadata meant until reading this article. The fact that it is just data about data makes it way easier to understand. I am finding that a lot of terms that we have used so far in class seemed hard to understand but are actually simple to do once they're broken down.

    1. IaskquestionsaboutthestructureandresultsofwebsearchesfromthestandpointofaBlackwoman—astandpointthatdrivesmetoaskdifferentquestionsthanhavebeenpreviouslyposedabouthowGoogleSearchworks.

      I agree with this. I think we should be asking and questioning things because that is how we learn and develop our ideas and opinions. Once we start questioning all of these things we can take this new knowledge and start to make changes.

    2. AtthecoreofmyargumentisthewayinwhichGooglebiasessearchtoitsowneconomicinterests—foritsprofitabilityandtobolsteritsmarketdominanceatanyexpense.

      I don't believe that Google should be biasing search to its own economic interests. I find that when I am searching things that my ads are targeted to what I have looked at previously or something that Google thinks I will like. As well, some of the other ads are completely random and not related to anything I have searched. I think that Google should base its ads on equality as well as its searches so you gain accurate information and not something put up to serve their own economic interests.

    3. TheGoogleSearchautosuggestionsfeaturedarangeofsexistideassuchasthefollowing:•Womencannot:drive,bebishops,betrusted,speakinchurch•Womenshouldnot:haverights,vote,work,box•Womenshould:stayathome,beslaves,beinthekitchen,notspeakinchurch•Womenneedto:beputintheirplaces,knowtheirplace,becontrolled,bedisciplined

      I can't believe that people are still thinking this way. Suggestions such as women cannot drive or be trusted and they should stay at home and be put in their places are not ones that we should be hearing anymore. Men and women are supposed to be viewed as equal and it shocked me that these came up as autosuggestions on Google Search. That shows that there is still a ways to go to fully achieve gender equality.

  18. Jun 2021
    1. Oversharing. Crying, disclosing intimate details, and telling long (unrelated and/or unsolicited) stories about one’s personal life may indicate the lack of an essential social work skill: personal boundaries.

      Testing out the annotate feature. Student 1 will highlight sections according to the prompts, as shown HERE.

      For example: "This is me during interviews. I say too much and veer off topic."

    1. nternal forces create the potential for a production function with increasing returns.

      This is a shortened version of the full definition to avoid vocab words we haven't defined yet

    2. Growth Comes From Within

      Starting off with Giacomo's slide content

    1. ZFIN: ZDB-ALT-130718-3

      DOI: 10.1016/j.celrep.2021.109255

      Resource: (ZFIN Cat# ZDB-ALT-130718-3,RRID:ZFIN_ZDB-ALT-130718-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-130718-3


      What is this?

    2. ZFIN: ZDB-ALT-140521-3

      DOI: 10.1016/j.celrep.2021.109255

      Resource: (ZFIN Cat# ZDB-ALT-140521-3,RRID:ZFIN_ZDB-ALT-140521-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-140521-3


      What is this?

    3. ZFIN: ZDB-ALT-120723-3

      DOI: 10.1016/j.celrep.2021.109255

      Resource: (ZFIN Cat# ZDB-ALT-120723-3,RRID:ZFIN_ZDB-ALT-120723-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-120723-3


      What is this?

    4. ZFIN: ZDB-ALT-100525-3

      DOI: 10.1016/j.celrep.2021.109255

      Resource: (ZFIN Cat# ZDB-ALT-100525-3,RRID:ZFIN_ZDB-ALT-100525-3)

      Curator: @Naa003

      SciCrunch record: RRID:ZFIN_ZDB-ALT-100525-3


      What is this?

  19. May 2021
    1. My advice is if you are looking for a quick and accurate answer ask to have the trouble ticket elevated immediately and to speak with an engineer that will recognize your knowledge and speak with you on your level.
    2. I typically request to speak with an engineer when I find myself detecting an inexperienced support person.
    3. In one of my internship, I got to befriend a level 2 tech support, so learned a couple thing of how it worked (in that company). Level 1 was out-sourced, and they had a script to go from, regularly updated. From statistics, this took care of 90% of issues. Level 2 was a double handful of tech people, they had basic troubleshooting tools and knowledge and would solve 90% of the remaining issues. Level 3 was the engineering department (where I was), and as a result of level 1 and 2 efficiency less than 1% of issues ever got escalated. The process worked!
    1. Reviewer #3 (Public Review):

      Barone, Paul et al. present a new computational method, named T-REX, to detect changes in immune cell populations from repeated cytometry measurements (before and after infection or treatment). The proposed method is designed to detect changes in rare and common cells with particular focus on the former. T-REX detects subpopulations of cells showing marked differences in abundance between the proportion of cells from different time points (before and after infection) from a single individual. The method relies of a dimensionality reduction step using UMAP followed by a K-nearest neighbor (KNN) search to identify cells that have a large fraction (>0.95) of neighbors from one time point, indicating expansion or shrinkage of certain cell populations. Areas in the UMAP with clustered expanding or shrinking neighborhoods are labeled as hotspots. Cells in these hotspots were further characterized and enriched markers were identified using MEM, a method published earlier by the same authors. T-REX was applied to a newly collected dataset of rhinovirus infection and three publicly available datasets of SARS-CoV-2 infections, melanoma immunotherapy and AML chemotherapy. The results are presented clearly and the authors discuss in details several examples in which the cells identified by T-REX have a phenotypic profile which align with previous knowledge, indicating the relevance of the results.

      Strengths:

      • T-REX is based on a simple pipeline including UMAP and KNN. This is an advantage especially given the large number of cells collected. Further, the proposed approach has a key advantage since it allows the analysis of one sample at a time, which is practical if one wants to analyze a new sample. There is no need to rerun the analysis on an aggregate of a large number of samples.

      • The new rhinovirus dataset is of great value to the community.

      Weaknesses:

      • The paper lacks a comparison to other methods for differential abundance testing. In particular, it is not clear how T-REX differs from the Differential abundance test proposed by Lun et al. (https://doi.org/10.1038/nmeth.4295). Similarly, there are no experiments or results to support the authors' initial claim that T-REX outperforms current clustering-based methods (SPADE, FLOWSOM, Phenograph,...etc.) in capturing changes in rare (<1%) cell populations.

      • T-REX relies on arbitrary cutoffs (0.95 and 0.5 %) to define expansion or shrinkage in the neighborhood of each cell (0.95 and 0.5 %) rather than a formal statistical test. These cut-offs were defined based on the ability to detect tetramer positive cells in one subject only. This greatly limits the generalizability of the method.

      • The authors do not motivate the use of UMAP prior to the KNN graph reconstruction. While UMAP is a clearly powerful method to visualize single cell data, the resulting embedding can potentially show distinct groups of points when the high dimensional manifold is more continuous. For this reason, KNN graphs are usually built using the high-dimensional data (or principal components).

      • Given that T-REX is mainly developed to detect changes in rare cell populations, the paper lacks an assessment of the method's sensitivity. For instance, cells were subsampled equally from each time point. An assessment of the effects of this subsampling step is necessary. In general, a guide to the users indicating the limitations of T-REX will be greatly helpful.

      • Given that the main aim of T-REX is to detect differences in rare cells, the rational to perform a separate analysis for CD4 positive cells is not clear. One would expect these differences to be identified also in the analysis performed using all cells.

      • The paper lacks a discussion on the effects of batch effects between the different time points on the performance of T-REX.

    1. Reviewer #3 (Public Review):

      This is an important manuscript on COVID-19 convalescent plasma (CCP) that challenges the findings of the larger Mayo Clinic CCP study demonstrating a lack of efficacy. Their main findings are that there is a strong inverse correlation between CCP use and mortality for admitted patients in the USA. Overall this is a well written manuscript without any overt weaknesses.

    1. Reviewer #3 (Public Review):

      In this study, Alhussein and Smith provide two strong tests of competing hypotheses about motor planning under uncertainty: Averaging of multiple alternative plans (MA) versus optimization of motor performance (PO). In this first study, they used a force field adaptation paradigm to test this question, asking if observed intermediate movements between competing reach goals reflected the average of adapted plans to each goal, or a deliberate plan toward the middle direction. In the second experiment, they tested an obstacle avoidance task, asking if obstacle avoidance behaviors were averaged with respect to movements to non-obstructed targets, or modulated to afford optimal intermediate movements based on a commuted "safety margin." In both experiments the authors observed data consistent with the PO hypothesis, and contradictory of the MA hypothesis. The authors thus conclude that MA is not a feasible hypothesis concerning motor planning under uncertainty; rather, people appear to generate a single plan that is optimized for the task at hand.

      I am of two minds about this (very nice) study. On the one hand, I think it is probably the most elegant examination of the MA idea to date, and presents perhaps the strongest behavioral evidence (within a single study) against it. The methods are sound, the analysis is rigorous, and it is clearly written/presented. Moreover, it seems to stress-test the PO idea more than previous work. On the other hand, it is hard for me to see a high degree of novelty here, given recent studies on the same topic (e.g. Haith et al., 2015; Wong & Haith, 2017; Dekleva et al., 2018). That is, I think these would be more novel findings if the motor-averaging concept had not been very recently "wounded" multiple times.

      The authors dutifully cite these papers, and offer the following reasons that one of those particular studies fell short (I acknowledge that there may be other reasons that are not as explicitly stated): On line 628, it is argued that Wong & Haith (2017) allowed for across-condition (i.e., timing/spacing constraints) strategic adjustments, such as guessing the cued target location at the start of the trial. It is then stated that, "While this would indeed improve performance and could therefore be considered a type of performance-optimization, such strategic decision making does not provide information about the implicit neural processing involved in programming the motor output for the intermediate movements that are normally planned under uncertain conditions." I'm not quite sure the current paper does this either? For example, in Exp 1, if people deliberately strategize to simply plan towards the middle on 2-target trials and feedback-correct after the cue is revealed (there is no clear evidence against them doing this), what do the results necessarily say about "implicit neural processing?" If I deliberately plan to the intermediate direction, is it surprising that my responses would inherit the implicit FF adaption responses from the associated intermediate learning trials, especially in light of evidence for movement- and/or plan-based representations in motor adaptation (Castro et al., 2011; Hirashima & Nozacki, 2012; Day et al., 2016; Sheahan et a., 2016)?

      In that same vein, the Gallivan et al 2017 study is cited as evidence that intermediate movements are by nature implicit. First, it seems that this consideration would be necessarily task/design-dependent. Second, that original assumption rests on the idea that a 30˚ gradual visuomotor rotation would never reach explicit awareness or alter deliberate planning, an assumption which I'm not convinced is solid.

      The Haith et al., 2015 study does not receive the same attention as the 2017 study, though I imagine the critique would be similar. However, that study uses unpredictable target jumps and short preparation times which, in theory, should limit explicit planning while also getting at uncertainty. I think the authors could describe further reasons that that paper does not convince them about a PO mechanism.

      If the participants in Exp 2 were asked both "did you switch which side of the obstacle you went around" and "why did you do that [if yes to question 1]", what do the authors suppose they would say? It's possible that they would typically be aware of their decision to alter their plan (i.e., swoop around the other way) to optimize success. This is of course an empirical question. If true, it wouldn't hurt the authors' analysis in any way. However, I think it might de-tooth the complaint that e.g. the Wong & Haith study is too "explicit."

    1. Reviewer #3 (Public Review):

      This is a well-presented study on the development of the CNS in the octopus O. vulgaris. The aim of the study is to identify the origin of the neural progenitors of the brain. The authors provide an excellent gene expression study of conserved neural genes to identify the location of these progenitors. Furthermore, by cell lineage tracing, they confirm the results of a previous study by Koenig et al. showing that the progeny of neural progenitors generated in the so-called lateral lips, a region adjacent to the eyes, migrate to different brain areas. The neural precursor location in the brain can be correlated with their spatial origin from the neural progenitors in the lateral lips. The authors suggest that the spatial map of the lateral lips is conserved in cephalopods. Furthermore, they analyse the mitotic activity in the developing brain by Ov-pcna in situ hybridisation and anti-PH3 immunohistochemistry. The authors conclude that "grossly, the embryonic octopus brain does not contain dividing progenitor cells." Based on the cell lineage studies, the strong expression of neural genes in the lateral lip and the observed mitotic activity, the authors overall conclude that the lateral lips represent the neurogenic zone in the developing brain of the octopus, i.e. that the neural progenitors of the brain derive from this area. I agree with the authors that the lateral lips are neurogenic regions, however, it is also possible that neural progenitors do arise from other regions of the developing brain. Overall this is a valuable contribution to our knowledge of neurogenesis in deuterostomian invertebrates and in a wider context the evolution of neural developmental processes.

    1. Reviewer #3 (Public Review):

      The manuscript of Oggenfuss et al presents a comprehensive analysis of TE insertion polymorphisms detected in the genome of ~300 isolates of the wheat fungus Zymoseptoria tritici. The article shows that numerous TE families generated thousands of polymorphic insertions and the authors propose that some of these insertions might potentially be linked to adaptation. They identified a recent burst of transposition in a rapidly expanding population, providing empirical evidence that drastic demographic process shape TE dynamics in nature. Last, they show that intra-specific variation in genome size can be accounted by variation in the number of polymorphic TE insertions, which recapitulate the well stablished association between TE content and genome size variation observed across the diversity of life forms.

      The article is well written, present novel as well as relevant results, and provide insights to our understanding of the role of TEs in microevolutionary processes. In addition, it provides an important amount of population genomic data that will serve as a resource. Thus, this manuscript is of potential interest to a broad audience on evolutionary and population genomics.

      My major concern is the lack of strong evidence supporting positive selection and/or functional relevance of the TE insertions detected. In particular, the selective sweep scans performed ignored other types of variants (such as SNPs and INDELs), preventing the identification of the actual targets of natural selection.

    1. Reviewer #3 (Public Review):

      In "Assembly of higher-order SMN oligomers is essential for animal viability, requiring a motif exposed in TG zipper dimers," Gupta et al. present an impressive amount of data regarding the solution behavior of constructs of the protein SMN1 (or just SMN) from Homo sapiens, Drosophila melanogaster, and Schizosaccharomyces pombe. Defects in the Hs protein are known to cause the neuromuscular disease "Spinal Muscular Atrophy" (SMA). They also present experiments in genetically modified organisms (fission yeast and fruit flies) to test their hypotheses. Bioinformatics are used to generate and refine hypotheses. The potential power of these complementary methods is substantial, if employed well.

      The main finding of these researchers is that the oligomerization potential of SMN and its disease-causing variants (usually in complex with the protein Gemin 2 or "G2") mostly correlates with phenotype severity. In humans, this is correlated with the Type of SMA (I/0 for severe disease, ranging to IV for a milder form), and in fruit flies and yeast, it is correlated with viability and, in some cases, animal behavior. The results are extended through the creation of a model that purports to show how higher-order SMN oligomers can form.

      Strengths:

      The experiments appear to have been carried out competently. There is a virtual mountain of data presented in this paper, and, for the most part, they are summarized in a digestible fashion. The effort to correlate the biophysical solution data with observable phenotypes in human patients or genetically modified organisms is laudable, and it is done in a thoughtful fashion. The authors' structural intuition and savvy enables the generation of testable models that are explored in the paper. A plausible model for higher-order oligomers is presented.

      Weaknesses:

      The most serious weakness of the paper is that the data cannot support the conclusion stated in the title, i.e. that multimerization of SMN is necessary for organismic viability. Instead, the data support an already-stated, decades-old conclusion (see their reference 21): that multimerization correlates with disease (viability). Even if the reader takes into account the new information about a multimerization interface that is separate from the dimerization one, the advance seems incremental.

      The large amount of data leads to numerous difficulties for the reader in the text:

      1) Complex biophysical measurements, due to space, are usually summarized by one or two words in tabular format.

      2) When these measurements are shown, there is no visual context for the reader to assess the pre-digested conclusions that are included in the figures. For example, all SEC-MALS data show a conclusion ("Tetramer-Octamer"), but there is no visual cue for the reader to know what the theoretical masses for these species are (so that the reader may draw an independent conclusion).

      In some cases, the conclusions reached in the paper are not clearly supported by the data or are self-contradictory. An example is the discussion of the residue H273 (human numbering). In Fig. 4B, the mutation H273R is said to have a wild-type "Oligomer Status". But in Fig. 5B, it is "Dimer-Tetramer+". The text says that H273R is "only partially impaired" in forming oligomers; the authors apparently mean the data presented in Fig. 5B but refer to the contradictory result in Fig. 4B. Another example centers on the discussion of the putative "dominant-negative" effect of some human missense mutations. But they do not point to any human data that support this contention (SMA-associated missense mutations are usually discovered in mixed heterozygotes have a deletion in the other copy of the Smn gene), but they cite data that suggest a more nuanced position regarding negative dominance would be appropriate.

      Finally, the paper suffers throughout from a lack of precision of language that undercuts its conclusions at numerous points. They continually rely on qualitative statements rather than hard, statistically rigorous facts, e.g. "more intimate," "a bit of a sequence outlier," "very modest."

    1. Reviewer #3 (Public Review):

      This study investigates the temporal orientation abilities of cerebellar degeneration and control subjects during an orientation discrimination task of visual stimuli with showed a contrast near threshold. Participants were queried to express their discrimination decision with a response only after a random delay following target offset, which decreases the motor preparation component of the task in the interval-based condition. CD subjects showed similar visual discrimination performance to controls when cued by a rhythmic set of stimuli but showed no benefit when the target interval was presented aperiodically. The authors interpret these findings as evidence supporting the notion that the cerebellum plays a role in interval based attentional orienting to proactively modulate perception. This is an elegantly simple experiment providing a novel observation in the field.

    1. Reviewer #3 (Public Review):

      The authors use a synthetic light-controlled transcription factor (GAVPO) to test a model of bistable gene expression that is hypothesized to originate from positive feedback via local histone modifications by trans-activator recruitment of CBP/p300 to facilitate open chromatin, which facilitates GAVPO binding, etc... Their proposed model for the origin of bistability is important because it should apply to any trans-activator that recruits CBP/p300 to modify chromatin and active gene expression. The authors show that periodic modulation of light reduces the bimodal distribution at intermediate light-intensity levels to a unimodal distribution. This is an elegant demonstration of how GAVPO and different temporal patterns of light can reduce cell-to-cell variability in gene expression, if needed.

      Strengths:

      The authors generate an impressive amount of single-cell data of gene expression and chromatin state (flow cytometry, single-cell sequencing, live-cell MS2-tagging) at different intensity levels. The periodic modulation of GAVPO activity by light is a practical demonstration of how to sculpt the gene expression output in useful ways. This may be a very useful tool for future biologists.

      Weakness:

      The proposed model for bistability is not convincingly tested or supported by the existing data. Each reporter should exhibit a bistable response because the positive feedback is localized to the promoter via cis-effects on gene expression by local chromatin state/GAVPO binding. The authors show a bimodal distribution of gene expression in a population of cells, which is consistent with a bistable response in a single reporter gene. However, their strain has 9 independent reporters integrated into the genome. Thus, I would expect to see up to 10 peaks, not 2 peaks. Moreover, the mathematical model used to validate their observations does not model the total expression from 9 independent promoters, which is a critical omission given the cis-nature of the positive feedback loop. The fact that these 9 promoters generate 2 peaks at intermediate light intensity suggests that the GAVPO bistability likely originates from a trans-effect, i.e., either all 9 promoters are OFF or all 9 promoters are ON, not a cis-effect.

    1. Reviewer #3 (Public Review):

      In this report the authors characterize a mechanism that plays a role in inducing the rhythmic depolarizations that are observed in identified neurons that are part of the feeding CPG in Aplysia. The neurons studied (B63 neurons) are of interest because previous work has established that they play an important role in triggering cycles of motor activity. Further, previous work from this group has demonstrated that activity in the B63 neurons can be modified by operant conditioning.

      The authors present this study as though previous work had established that plateau potentials generated in the B63 neurons play an important role in driving network activity. For example, in line 102 they state "This essential role played by B63 is partly mediated by a bistable membrane property, which allows the sudden switching of the neuron's resting membrane potential to a depolarized plateau..." To support this statement, they reference Susswein et al. 2002, which does not support this statement. In the Susswein et al. study it is the B31/32 neurons that are modeled as having plateau properties.

      If previous work has not established the role of the B63 plateau potentials, the only data that speak to this issue are presumably in the current report. In this study the authors do provide data that indicate that the B63 neurons generate low amplitude oscillations that are not likely to depend on input from the electrically coupled neurons studied (notably B31). The authors also show that in some instances, these depolarizations do trigger plateau potentials in B63. It is, however, not clear that the B63 generated plateau potentials are then responsible for triggering network activity (e.g., as opposed to a situation where depolarizing input from B63 triggers plateau potentials in B31/32 and the depolarization in B31/32 drives the rest of the feeding circuit). For example, in Figs. 6A and Supplemental Fig. 4A it does not appear that the plateau depolarization in B63 is being transmitted to other electrically coupled neurons to any large extent.

      A clarification of this issue is important because it potentially impacts thinking concerning how 'decision making' is occurring. If decision making means induction of a motor program and this does not occur unless the depolarization in B63 is transmitted to B31/32, the process is more complicated than what the manuscript currently suggests.

      The title is misleading since there are no studies of behavior in this report.

      In part, interest in the mechanisms that drive spontaneous oscillatory activity in the B63 neurons stems from the overall context of this work. Namely the authors have previously established that oscillatory activity can be modified through associative learning. In the Sieling et al. 2014 study they demonstrate that two aspects of plasticity are accounted for by changes in synaptic properties and an effect on a leak current. For readers trying to understand this body of work as a whole, the Discussion should more clearly indicated how the results of the present study integrate with these previous findings.

    1. Reviewer #3 (Public Review):

      Some Gram-negative bacteria synthesize acyl-homoserine lactone molecules, which are secreted into the environment and then transported into nearby bacteria, where they are detected by receptors. Different species make acyl-homoserine lactones that differ in chain length and oxidation state at the C-3 position. The manuscript by Wellington et al. reports an elegant and compelling investigation of the specificity determinants involved in quorum sensing, using a combination of bioinformatics and experimental approaches.

      Over the course of evolution, if an amino acid change occurs in one protein, then a compensating change can occur in a partner protein to restore/retain a functional interaction between the two. Analyses of evolutionarily covarying positions between two interacting proteins, or within a single protein, have long been used to identify positions that directly interact. Wellington et al. applied the same approach to two protein families (the synthases and receptors for acyl-homoserine lactones) to identify positions that are connected not by direct physical interaction between the two proteins but rather by interaction with the same acyl-homoserine lactone. The covariation analysis was made possible by the fortuitous case (and reasonable assumption) that genes encoding partner synthases and receptors are located close to one another within bacterial genomes.

      The covarying residues turn out to be in the active site of the synthase and the binding site of the receptor, in positions that directly interact with the acyl-homoserine lactone. The authors made a variety of single amino acid substitutions at positions with high covariation scores in the Pseudomonas aeruginosa LasI synthase and LasR receptor proteins. The mutant proteins exhibited altered synthetic and detection specificities for acyl-homoserine lactones. Altering three residues simultaneously resulted in substantial changes in specificity.

      This paper constitutes a proof of principle for an approach that could be used to investigate other families of proteins connected by interactions with small molecules (e.g. metabolic pathways). Furthermore, it suggests a path toward rational engineering of quorum sensing systems for synthetic biology, as well as specificity prediction for uncharacterized quorum sensing pathways based simply on the primary amino acid sequences of the synthase and receptor proteins.

    1. Reviewer #3 (Public Review):

      The manuscript titled "The Shu complex prevents mutagenesis and cytotoxicity of single-strand specific alkylation lesions" investigates the biological function of the Shu complex in S. cerevisiae. The Shu complex, containing a DNA binding module comprised of the Csm2-Psy3 heterodimer, is conserved from budding yeast to man, and contributes to the defense against DNA damage caused by DNA alkylation. DNA alkylation occurs due to spontaneous reactions with metabolites and can be greatly increased by exogenous exposure to DNA alkylating agents. Therefore, it is an important question for how the Shu complex acts to detect and direct repair of alkylation damage. It has been well established that loss of the Shu complex sensitizes cells to alkylation damage, but the mechanism by which this complex locates sites of DNA damage and directs repair is not fully understood. This paper measures the methylation-induced mutation spectrum and uses genetic interactions to argue that the Shu complex may be involved in detecting and directing error-free repair of 3-methyl cytosine. This is a plausible hypothesis based on the body of previous work, however the evidence that Csm2-Psy3 directly detects 3-methyl cytosine sites is indirect. It would be highly significant if this complex recognizes many different structures, but future structural information is needed to understand how this could be possible.

      The strengths of the paper are in the use of whole genome sequencing to map mutation type and location in different genetic backgrounds and in the systematic testing for genetic interactions between csm2 and other DNA repair factors. It appears that the mutation spectra are very similar in the presence and absence of csm2, which suggests a broad role of the Shu complex in the cellular response to MMS.

      The impact of the work is that it could help to explain the cellular program for protection against DNA alkylating agents in budding yeast which has been a very valuable model eukaryotic organism, and raise new questions about how DNA alkylation repair pathways might function in humans that differ from yeast in important features such as in the presence of a direct repair pathway performed by ALKBH2 and ALKBH3.

    1. Reviewer #3 (Public Review):

      The authors tackle an interesting question - whether the dentate gyrus is a locus of pathology in Scn1a+/- mice and uncover a strong phenotype - the granule cells of the dentate gyrus are over-activated and the EC to dentate pathway is prone to seizure genesis. In the discussion, they suggest that their results support the idea that the DG may be a common locus to several different types of epilepsy... an attractive hypothesis! There are several strengths of the paper. The team has done a nice job of presenting 'ground-truth' data that their measurements of dF/F across a large population of granule cells correlates with action potentials in these cells. As the authors point out, this is especially important when working in disease models in which the dF/F-action potential relationship may be altered. Throughout, the authors were also careful about considering the limitations of their various techniques and analyze the data in several ways to account for possible artifacts (e.g. ensuring that differences in activation are not arising because of slicing and consideration of kindling in later in vivo seizure threshold experiments). The experiments were well designed and appropriately interpreted.

      One of most intriguing results of the work is that PV interneurons in the DG of Scn1a+/- show only very minor impairments in young adult animals (they show more spike accommodation than in control animals). Rather, it seems that the GCs receive enhanced excitation from the entorhinal cortex. They perform a set of pharmacological experiments to prove that PV interneurons (and more generally inhibition) do not account for the difference in granule cell activation - however, here it would be useful to see the data summarized more consistently. It is difficult to interpret the pharmacological results (both of which are presented as changes in dF/F0) with respect to the initial findings of the manuscript (presented as estimated activation across the entire population). A beautiful aspect of this work is that it goes from cells to circuits to intact brain (in vivo). They nicely show that the heightened excitation from the EC to the DG is sufficient to drive seizures in the Scn1a+/- mice, and finally that since PVs are intact, they can be harnessed to balance out the over activation of GC via optogenetic stimulation of PVs.

    1. Reviewer #3 (Public Review):

      The manuscript endeavors to explain the mechanism of action of a Gram-negative bacterial outer membrane (OM) TonB-dependent transporter (TBDT), that acquires metabolites (in this case vitamin B12) from the external environment. The authors use electron paramagnetic resonance spectroscopy to monitor the proximity of different parts of OM protein to one another during the binding of B12. Their data show that different conformations of the target protein occur during the binding of B12.

    1. Reviewer #3 (Public Review):

      Inamdar et al. used biochemical and microscopy assays to investigate the role of I-BAR domain host proteins on HIV-1 assembly and release from HEK 293T and Jurkat cells. They show that siRNA knockdown of IRSp53, but not a similar I-BAR domain protein IRTKS, inhibits HIV-1 particle release from 293T cells after transfection of the HIV-1 provirus or HIV-1 Gag in cells. The authors then show that HIV-1 Gag associates with IRSp53 in the host cell membrane and cytoplasm, using biochemical assays and super resolution microscopy. In addition, IRSp53 is incorporated into HIV-1 particles along with other previously identified host proteins. Then using in vitro-derived membrane vesicles ("giant unilamellar vesicles" or GUVs), the authors indicate that HIV-1 Gag can associate with IRSp53, particularly on highly curved structures.

      The conclusions are largely supported data, with the virology and biochemical results being particularly strong, but the mechanistic studies in GUVs appear somewhat preliminary and are not entirely clear. The GUV experiments would benefit from better quantification of measurements and manipulation to simulate actual cellular scenarios. In addition, while it is appreciated that the HEK 293T cell line is convenient for biochemical and imaging studies, they are not biologically relevant HIV-1 target cells. While the authors present examples of reproducibility of their results in a CD4+ T cell line, these data are buried in the supplemental figures, whilst it would have been better to highlight them and perhaps include primary CD4+ T cells.

      1) Immortalized cell lines do not always recapitulate primary cells. It is unclear what the role of IRSp53 is in the membrane curvature of CD4+ T cells and whether expression levels and localization are consistent with Jurkat T cells.

      2) Description of some of the microscopy measurements could be improved. In lines 204-206 of the text and Figure S5, it is unclear how the localization of precision was determined to be approximately 16 nm for PALM-STORM. In Figure 4b, it is understood from the text (lines 252-256) that the red bars denote the Mander's coefficient for colocalization of the GFP-tagged proteins with Gag-mCherry (presumably the average of multiple experiments with standard deviations or errors of the mean, although this is not stated in the figure legend), it is unclear what the green bars are showing. Also, the histograms for IRSp53 and IRTKS colocalized with Gag look similar in Figure S10, suggesting that they are not different in Jurkat cells, but this is not addressed.

      3) GUVs are first referenced on page 7 after description of Figure 2, the significance of which is confusing to the reader. However, the actual experimental data are described on pages 12-13 and Figures 5 and S11. A better description of these structures would be warranted for an audience that is unfamiliar with them. In addition, the biologic concentrations of I-BAR proteins at cell membranes are not provided and it is unclear what conditions used in Figures 5 and S11 represent a "normal CD4+ T cell" situation. It appears that the advantage of this in vitro system is that different factors can be provided or removed to simulate different cellular scenarios. For example, relatively low IRSp53 concentrations may simulate siRNA knockdown experiments in Figure 1, which could recapitulate those results that less viral particles are released from the membrane. In addition, the authors state that HIV-1 Gag preferentially colocalizes with IRSp53 as the tips of the GUV tubular structures (Figure 5b,c), but this is not actually shown or quantified. Similar quantification as shown in Figure 1e could be performed to strengthen this argument.

    1. Reviewer #3 (Public Review):

      Gentile, A. et al. generated snai1b mutant zebrafish embryos and showed that loss of Snai1b led to two mutant phenotypes in the heart: i) hearts with clear looping defects, ii) hearts without looping defects that displayed abnormal cardiomyocyte (CM) extrusion. The authors focused on the second class of mutants and found that loss of Snai1b led to reduction of N-cadherin at cell junctions and basal accumulation of phosphorylated myosin light chain and the α-18 epitope of α-catenin, indicative of mechanical activation. Bulk RNA-sequencing of isolated hearts revealed an upregulation of intermediate filament (IF) genes in Snai1b mutants, and of particular interest, the authors identified upregulation of the muscle-specific IF gene desmin b. Immunofluorescent imaging revealed that Desmin was not only upregulated in Snai1b mutants, but mis-localized away from cell junctions and accumulated at the basal side of extruding cells along with actomyosin machinery. Accordingly, CM-specific overexpression of Desmin was sufficient to promote cell extrusion.

      The presented work is particularly interesting because it identifies a new role for the Snai1b transcription factor in maintaining proper tissue structure, independent of its typical function in regulating epithelial to mesenchymal transition (EMT). Overall, the experiments were well designed and controlled, and the data is clearly and logically presented. However, some of the findings could be explained by alternative hypotheses and other interesting aspects of the data were left unexplored.

      One hypothesis that was not sufficiently discussed is that loss of Snai1b may prevent cardiomyocytes from undergoing the EMT that is necessary for normal delamination and trabeculation, and thus cells are instead extruded away from the lumen to prevent overcrowding in the developing myocardium. In fact, the authors present evidence that EMT is blocked and acknowledge that extrusion is a known mechanism for preventing overcrowding. It would be interesting to see whether extrusion away from the lumen also occurs if EMT is blocked through other means.

      The authors show that extruding cells do not seem to be dead or dying, and that a small number of CMs do extrude in wild type embryos. This raises the intriguing possibility that some amount of CM extrusion is necessary for normal development and that these cells may give rise to epicardial or other cell types. Live-imaging and lineage-tracing studies would inform whether the extrusion observed in mutant embryos is an enhancement of a normal morphogenetic process or an additional abnormal response to loss of Snai1 function.

      One particularly interesting observation that was left unexplored was the identification of a second class of Snai1b mutants with defective heart looping. It isn't clear whether these embryos also display enhanced CM extrusion, or if there are other clearly aberrant cell behaviors. Furthermore, it would be very interesting to know whether there is any evidence that the defective looping is due to the same changes in cytoskeletal gene expression and protein organization observed in the class of Snai1b mutants that were detailed throughout the manuscript.

      The authors suggest that Snai1b regulates Desmin in two ways: 1) overall expression levels, and 2) post-translationally to control its localization at cell junctions. Although the first claim is sufficiently supported, the second claim lacks experimental evidence. An alternative explanation is that overexpression of Desmin in response to loss of Snai1b leads to mislocalization independent of an interaction with Snai1b. This point could be clarified by examining Desmin localization in the desmb overexpression system. In addition, assaying for co-IP of Snai1b and Desmin could demonstrate a direct interaction between the two and better support a role for Snai1 in regulating post-translational localization of Desmin.

      Although the authors convincingly show that Desmin accumulates with other contractile machinery at the basal side of extruding CMs in Snai1b muntants, additional evidence is needed to support a causal link between basal Desmin accumulation and extrusion. For instance, if knockdown or inhibition of Desmin prevents extrusion in the Snai1b mutants, the causal relationship would be much clearer.

    1. Reviewer #3 (Public Review):

      This manuscript investigates the structure, electrophysiological and biological functions of a novel mechanosensitive channel from the parasitic protist Trypanosoma cruzi. The channel was identified bioinformatically as being significantly related in sequence to known mechanosensitive channels of the McsS superfamily. Studies on channel proteins in pathogenic protists such as trypanosomes are limited, and this investigation focuses on a previously unstudied mechanosensitive channel which is of potential interest to parasite biology, because trypanosomes are subjected to various mechanical stress forces during their life cycles.

      Analysis of the sequence of the TcMscS protein by bioinformatics and structural prediction concludes that it is relatively divergent from previously studied members of the family from other microorganisms. Of particular interest, the divergent C-terminal domain contains a proposed novel cytoplasmic gate that could filter solutes on the cytosolic side. These observations are predictive rather than data driven. The recombinant protein was expressed in E. coli giant spheroplasts and studied by cell-detached patch clamp electrophysiology. The authors have clearly demonstrated that the channel is activated by pressure steps and fluxes K+, Cl-, Ca2+, and they speculate that it may be able to transport osmolytes such as amino acids. Other well supported conclusions are that the channel is located primarily in the contractive vacuole complex (CVC) in insect vector stage epimastigotes, an organelle that expels water from the parasite, but it occupies a wider range of subcellular sites in infective metacyclic and bloodstream trypomastigotes, and it localizes primarily to the plasma membrane of amastigotes. Thus, the channel changes its location during the life cycle. A MscS knockout line was generated and demonstrably shown to have impaired cell volume regulatory responses when subjected to changes in extracellular osmolarity, decreased motility, reduced ability to transform into infective stages such as metacyclic trypomastigotes, amastigotes, and bloodstream trypomastigotes, and altered Ca2+ homeostasis. Hence, the biological impacts of this channel are broad and significant.

      A strength of the manuscript is that it is well-executed study and examines many aspects of channel function and biology. Precisely how the channel mediates the biological functions is less clear and will require future investigations. For instance, whether the channel has functions related to shear stresses encountered by the parasites when they enter host cells or extravasate through vasculature is currently rather speculative, albeit of considerable potential interest. How the channel mediates volume changes or affects motility is also unclear. In addition, the manuscript would benefit from some editing to make several points or interpretations clearer to the readers.

    1. Prestige Sector 150 Noida

      Prestige Group Sector 150 in Noida is the latest project of a well-known real estate builder i.e Prestige group’s pioneer to yield one of the best residential property in Noida including 2/3/4 BHK luxury & lavish apartments with great amenities. There are lots of residential facilities such as Vaastu compliant design, double-height entrance lobby, Tower heights- G+19 & G+22, and facing green landscape. etc. Apart from that, you can also get state-of-the-art facilities such as a green area, swimming pool, clubhouse, children play area, power backup, etc.

    1. Reviewer #3 (Public Review):

      The sodium-coupled biogenic transporters DAT, NET and SERT, terminate the synaptic actions of dopamine, norepinephrine and serotonin, respectively. They belong to the family of Neurotransmitter:sodium:symporters. These transporters have very similar sequences and this is reflected at the structural level as judged by similarity of the crystal structures of the outward-facing conformations DAT and SERT. However, earlier functional studies indicated that transport by SERT is electroneutral because the charges sodium ions and substrate moving into the cell are compensated by the outward movement of potassium ions (or protons) to complete the transport cycle. On the other hand, DAT and NET are electrogenic. Moreover, potassium ions are not extruded by these transporters and the Authors set out to investigate if the electrogenicity is related to difference in potassium handling between SERT and the two other biogenic transporters. This was done by analyzing the role of intracellular cations and voltage on substrate transport by the three biogenic amine transporters. This was achieved by the simultaneous recording of uptake of the fluorescent substrate APP+ and the current induced by this process under voltage-clamp conditions by single HEK293 cells expressing the transporters. The Authors found that even though uptake by NET and DAT did not require internal potassium, these transporters could actually interact with internal potassium as judged by the voltage dependence of the so-called peak current. This voltage dependence was very steep in the absence of both sodium and potassium. However, in the presence of either cation this voltage dependence became less steep when either of these cations was present in the internal milieu, indicating that not only sodium but also potassium could bind from the inside. The same result was obtained with SERT. However, uptake by SERT was found to be much less dependent on the membrane voltage than that by DAT and NET and was stimulated by internal potassium, consistent with the proposed electroneutrality of the former. The observations indicate that the structural similarity of the three biogenic amine transporters is also reflected in their ability to bind potassium, even though this cation can translocate to the outside only in SERT.

      Strengths:

      Development of a sophisticated technique to interrogate the mechanism of sodium coupled biogenic amine transport in single cells. Rigorous analysis of the data. Conclusions supported by the data. The methodology can be used to obtain novel insights into the mechanism of other transporters.

      Weaknesses:

      The presentation could be made more "user friendly" by explaining in more detail what is happening as we go through the data. For instance, peak and steady state currents are shown already in Figure 1, but an (too brief) explanation is only provided when describing Figure 5. A schematic in the first part of the Results would be useful. Some information of on the structural background should be provided as well as a full description of the transport cycle, namely the number of sodium ions translocated per cycle and the argument why chloride remains bound to the transporter throughout the cycle. The control that in contrast to potassium, lithium is inert should be performed not only for DAT, but also for the two other transporters.

    1. Reviewer #3 (Public Review):

      The authors developed an in vivo model of EBV's contribution to RA that recapitulates aspects of human disease. They examined the role of age-associated B cells and find that they are critical mediators of the viral-enhancement of arthritis.

      The manuscript is written in a well-structured form that facilitates the reading and following the incremental experimental setups. The manuscript is appropriate for publication after revisions.

      Some of the statistical measures did not show significant values while the author based several statements as if there is a difference (they rather used phrases as increased/fold change). Whether this is strong enough to support their statements is not clear.

      Overall, this report provides important insights regarding the association between latency, age-associated B cells, and the enhancement of RA in a mouse model. If these insights are translatable to RA immunology in humans is to be further investigated.

    1. Reviewer #3 (Public Review):

      Proper sealing of the blood brain barrier (BBB) is essential for viability in many animals, including humans and Drosophila. In Li et al., the authors used Drosophila as a simple genetic system to define the signaling pathways that control BBB formation and maintenance. In Drosophila, the BBB is composed of a thin epithelial sheath of subperineural glia (SPG) that are connected by septate junctions. Previously, the authors found that the G protein-coupled receptor Moody is essential for BBB formation during embryogenesis, but the downstream signaling pathways that facilitate septate junction assembly were not known. Here, they performed a series of genetic screens and epistasis experiments to uncover that Moody and PKA antagonistic signaling drives BBB assembly and expansion throughout organismal development. In the present study, they show that loss of PKA signaling components results in a leaky BBB both during development, and during adulthood. They further show that these functions of PKA are dependent on downstream suppression of Rho and changes in cytoskeletal dynamics. Interestingly, overexpression of PKA also causes BBB permeability, indicating that PKA signaling levels must be tightly regulated for BBB integrity. The authors then use serial section TEM to visualize the intact SPG sheath for the first time at ultrastructural resolution, and show that overexpression of PKA results in an enlarged yet patchy septate junction, accounting for the leakiness. In sum, the authors show that the combined signaling of Moody (apically located) and PKA (basally located) shapes the cytoskeleton to drive efficient assembly and maintenance of septate junctions, and thus, the BBB.

      The conclusions of this paper are mostly well supported by the data, but the study would be improved by some expanded analyses and descriptions of statistical assessment.

    1. Reviewer #3 (Public Review):

      The authors have re-sequenced 310 quinoa accessions and carried out field phenotyping of the same set of accessions for two years in order to characterize genetic diversity and analyze the genetic basis of agronomically important traits.

      The main strength of the manuscript is that the authors have carefully characterized more than 300 quinoa accessions, achieving a sufficiently large population size for GWAS analysis with good statistical power. It is especially promising that the phenotypes all show high heritability. This indicates that the field phenotyping was of high quality and provides a good starting point for discovering relevant marker-trait associations. In addition, the authors provide convincing evidence for distinct population characteristics of highland and lowland quinoa, adding additional information compared to previous work (Maughan, 2012).

      The weak points are related to the genotype data and the conclusions drawn based on the GWAS analysis.

      1) An important issue is related to the relatively low depth of coverage (4-10x) that was used for re-sequencing. Across the accessions, there is a pronounced negative correlation between the mean sequencing depth and the heterozygosity level, indicating that heterozygotes are overcalled in individuals with low coverage. This also results in heterozygosity levels that are generally higher than expected for what is assumed to be mainly homozygous inbred lines.

      2) Another potential issue concerns SNPs called in repetitive regions. Among the significant GWAS SNPs identified, a very large proportion appears to be found in intergenic regions. While this does not rule out that some of them are genuinely important associations, it does suggest a potentially high level of noise in the GWAS results. In addition to the filtering already imposed, which includes a filter for mapping quality, the SNPs called in intergenic regions with unusually high coverage could be more closely examined to determine the extent of the issue. Masking repetitive genomic regions using RepeatMasker or similar programs could be useful.

      3) When the authors discuss their GWAS results, they frequently focus on cherry-picked candidate genes, although, in several cases, the top SNPs in the region in question are not found within these candidates. A more broad focus on all genes within the LD blocks, while still mentioning the candidate genes, would be more informative.

      4) The manuscript includes statements that a particular genotype "results in" some phenotypic outcome, although no causal relationship has been demonstrated. In general, there is a tendency to draw too strong conclusions based on the GWAS results.

      5) As this is primarily a resource paper, the authors should make the complete genotype and phenotype data as well as the layout of the field trials available. It would not be possible to reproduce the GWAS analysis based on the data included with the current version. They should also clarify how the quinoa accessions described will be made accessible to the community and provide all scripts used for data analysis through GitHub or a similar repository.

    1. Reviewer #3 (Public Review):

      Cole and co-authors report the development of a novel immunofluorescence technique, where targets of interest are analysed over iterative cycles of staining-imaging-elution(stripping). This method allows for the multiplexed analysis of protein targets, well beyond the usual constraints of such technique (limited by availability of filters and non-overlapping wavelengths of fluorophores). The authors also present several applications of such technique, highlighting how the advantage of being able to record additional parameters (such as cell morphology) can be an advantage over more high-throughput methods such as spatial-resolved transcriptomics.

      The technique has been carefully tested. Staining for the same markers after several rounds of stripping/reprobing shows high concordance, indicating that the iterative treatment and staining of the same tissue section is not altering the detection of protein markers.

      The authors tested staining with a total of 18 antibodies, and suggest that this number can be increased arbitrarily, as the number of iterations is not limited. Further, they suggest that this technique can be applied to virtually any tissue. It is quite possible that this technique can be readily applied to any other tissue, as the only constraint seem to be the robustness of antibodies. The authors may include the suggestion that previous success of immunofluorescence on a particular tissue type could be a good indication for the success of the iterative staining.

      The proposed 4i method is quite interesting, has great potential and is likely to be of very wide interest.

    1. Reviewer #3 (Public Review):

      This manuscript seeks to provide mechanistic insight into the role of GJA1-20k in mitochondrial changes that protect against ischemia-reperfusion damage. In previous studies, this group has shown that GJA1-20k protein increases in response to ischemic stress, localizes to mitochondria, promotes mitochondrial biogenesis, and mimics ischemic preconditioning protection in the heart. These changes did not coincide with changes in mitochondrial dynamics proteins, but the increase in GJA1-20k provides protection through an unknown mechanism. This makes it a potentially attractive therapeutic candidate for protection against ischemia.

      The evidence in this manuscript shows that mitochondrial size is affected by GJA1-20k, as over-expression of this fragment reduced mitochondrial area. The authors argue that this change in morphology is independent of Drp1 activity, and actin dynamics drive mitochondrial division. These ultrastructural changes coincide with cytoprotective effects during reperfusion following ischemic events by limiting ROS production.

      Strengths:

      The data on ultrastructural changes is convincing, and GJA1-20k induced a decrease in mitochondrial size. The imaging looks good and quantification is helpful in the evaluating the impact of these changes.

      To complement the use of proposed Drp1 inhibitors, the authors use genetic knock-down (KD) of Drp1, and the KD looks robust. Still see some Drp1 colocalization on the mitochondria in the KD, but the levels are diminished.

      The decrease in ROS when HEK cells were treated with H2O2 is convincing. And this coincides with the decreased respiration capacity observed in the Seahorse analysis. This provides some mechanistic insight about a specific change in mitochondrial function that contributes to the protective effects observed.

      Weaknesses:

      With the introduction of GJA1-20k, there is clearly a difference in mitochondrial size, and total mitochondrial content appears unaltered (i.e. Tom20 does not increase). Previously it was suggested that mitochondrial biogenesis was increased with increased levels of GJA1-20k. Is this a difference in the cellular model (HEK) and do the changes in cell culture accurately recapitulate the changes seen in animals? Having more mitochondrial mass despite decrease in the avg. size of these organelles may represent an important difference.

      Mdivi-1 is not a selective Drp1 inhibitor. It is a Complex I inhibitor, leading to unintended changes in mitochondrial dynamics in response to ETC stress. Rather than Mdivi-1, a dominant negative Drp1 mutant K38A could be overexpressed to see whether this prevents GJA1-20k-mediated fission. If it still goes through, then I agree that Drp1 is not involved at all.

      For the kinetics studies (see Fig 4), I think it is important to measure the timing of the actin recruitment and eventual fission when Drp1 is knocked down and/or when a DN mutant (K38A) is involved. Again, I do not trust the chemical inhibitor (Mdivi-1) data since this does not inhibit Drp1 activity.

      The assessment of the impact of ischemic stress with the heterozygous animal (M213L/WT) is hard to interpret. How reduced is the expression of GJA1-20k in these animals and how is mitochondrial function impacted based on Seahorse analysis? The mitochondrial morphology is not altered in these animals, so would mitochondrial function be largely unchanged as well? It is not clear how much GJA1-20k is needed to observe changes in mitochondrial shape and function, and comparisons with the homozygous mutant (M213L/M213L) are not the same, making it difficult to resolve the interpretation of these data.

      It is still unclear to me how GJA1-20k is affecting mitochondrial size and function. Based on previous papers, this peptide localizes to the surface of mitochondria, but it is not clear how, or whether, it directly facilitates actin recruitment. The interplay with the endoplasmic reticulum (ER), which can nucleate actin at sites of mitochondrial fission, was not examined. If actin is driving membrane remodeling, is it mediated by ER crossover at these sites?

    1. Reviewer #3 (Public Review):

      Nguyen Lam Vuong et al performed a nested case control study of a multisite, multicountry prospective dengue study (IDAMS) to identify early biomarkers at day 1-3 of illness onset that predicts for severe dengue of ten biomarkers. Ten biomarkers from the inflammatory, immune or vascular pathways (VCAM-1,SDC-1, Ang-2, IL-8, IP-10, IL-1RA, sCD163, sTREM-1, ferritin, CRP) were chosen based on prior literature and understanding of dengue pathogenesis in severe disease. The biomarkers were measured at two time points: at enrollment (illness day 1-3) and after recovery(day 10-31 ). They find moderate-to strong positive correlations for some markers, particular IP-10 and IL-1RA, and IP-10 and VCAM-1, ( Spearman's rank correlation coefficients above 0.6). Interestingly, in their single modal analysis, they also find differences in biomarkers levels in children compared to adults, Associations between SDC-1 and IL-8 and the S/MD endpoint were stronger in adults than children, while the effects of IL-1RA and ferritin were stronger in children than adults. When global analysis was performed, only SDC-1 and IL-1RA were the most stable relative to the single models for both children and adults. And the the differences of the associations between children and adults were more marked, particularly for Ang-2, IL-8 and ferritin. When the biomarkers were combined, for children, the best subset that showed the clearest association with S/MD was the combination of the six markers IL-1RA, Ang-2, IL-8, ferritin, IP-10, and SDC-1 with an AIC of 465.9. For adults, the best subset included the seven markers SDC-1, IL-8, ferritin, sTREM-1, IL-1RA, IP-10, and sCD163 This manuscript certainly provides useful insight into the biomarkers that are involved in the early phase of dengue before onset of vascular leakage or severe dengue which is valuable as most previous publications mainly focused on measurement of these markers after onset of severe disease which was often too late for meaningful interpretation of the disease biology or of limited clinical utility. The conclusions of this paper are mostly well supported by data, but some aspects of study and data analysis need to be clarified in order to improve understanding of the statistical methodology and readability.

      Major Strengths:

      • More than 7000 participants ( children and adults) in eight countries across Asia and Latin America were enrolled in the IDAMS study
      • Prospective and systematic blood sampling starting from day 1 of illness onset
      • Cases were laboratory confirmed via PCR or NS1 testing
      • Cases and control were fairly well- matched
      • Strong rationale for selection of host biomarkers

      Weaknesses:

      • Three quarter of cases from one country
      • Serotype-1 biased

      Specific comments to address:

      1) For general ease of readership, it would greatly help if the authors can explain the choice of the statistical method used in the data analysis and perhaps briefly explain the model and how AIC should be interpreted in the main rather than the supplementary text).

      2) While this reviewer understands that the authors want to focus on host immune and inflammatory biomarkers but it would be helpful if NS1 and viremia data are also shown ( at least in supplementary data) if these have been found not to correlate with disease severity.

      3) It is Interesting to note that some biomarkers ( particularly the vascular markers) in severe group do not return to the same baseline as mild cases at convalescence even after >20 days. Whether such individuals already are at higher inflammatory state at baseline (pre-infection) as a result of underlying co-morbidities such as obesity or diabetes? Table 1 did not provide such information but would be interesting to show if there is any difference in health state in the 2 groups especially for obesity.

      4) It is rather confusing that the 2nd paragraph of discussion stated "Balancing model fit, robustness, and parsimony, we suggest the combination of five biomarkers IL-1RA, Ang-2, IL-8, ferritin, and IP-10 for children, and the combination of three biomarkers SDC-1, IL-8, and ferritin for adults to be used in practice."

      But the concluding paragraph went on to state "The best biomarker combination for children includes IL-1RA, Ang-2, IL-8, ferritin, IP-10, and SDC-1; for adults, SDC-1, IL-8, ferritin, sTREM-1, IL-1RA, IP-10, and sCD163 were selected." This should be clarified further.

    1. Reviewer #3 (Public Review):

      In this paper McPherson and Bandres investigated temporal and regional features of spontaneous neural activity in the spinal cord of anesthetized unconscious rats from multi-unit electrophysiological recordings of neuronal activity in the lumbar spinal cord. Spontaneous temporally correlated neural activity in the mammalian central nervous system during unconsciousness is a feature of supraspinal circuits, and recent studies from resting-state fMRI in the spinal cord of non-human primate and in the human spinal cord indicate that spontaneous activity in the absence of sensory stimulus-evoked activity and spontaneous motor output is also a basic property of spinal cord circuits. Here the authors sought to provide more direct evidence of robust and temporally correlated spontaneous neuronal activity in the in vivo mammalian spinal cord by applying correlation-based analyses of activity with single neuron resolution from multi-unit electrophysiological recordings simultaneously in several dorsal and ventral regions of a lumbar spinal cord segment. They successfully demonstrated robust spontaneous activity in these regions, and their correlation analyses of temporal features of this activity, to infer functional connectivity between spontaneously co-active neuronal units, suggests functional connectivity between sensory- and motor-dominant regions of the spinal cord, in addition to intraregional connectivity. This includes finding evidence for mono- and di-synaptic neuronal interactions as well as excitatory and some inhibitory interactions. Evidence is also presented that the spatiotemporal patterns of this spontaneous activity could not be explained theoretically by randomly spiking interconnected neurons, leading the authors to speculate that the spontaneous activity is intrinsic to the spinal cord and may reflect some type of replay of more structured experience-dependent patterns occurring during conscious behavior. The origins and functional significance of this temporally correlated spontaneous activity, however, remain to be determined.

      Strengths of the paper include: (1) Clearly presented descriptions of the authors' procedures for recordings of multi-unit electrophysiological activity with a dual-shank 32 channel microelectrode array positioned at lateral and medial regions of the lumbar hemi-cord. (2) Novel reconstructions of functional connectivity maps, from correlation-based analyses, which enabled some topological features of the activity correlations to be represented from microelectrode array geometry and location within the rat spinal cord. (3) Novel results at the single neuron level potentially indicating spontaneous functional connectivity between sensory and motor regions in the unconscious animal. (4) Appropriate discussion of important caveats associated with technical aspects of their correlation analyses including problems for inferring functional connectivity in the presence of polysynaptic connection pathways and shared synaptic inputs as well as limitations of detecting inhibitory connections via correlation-based approaches. (5) Insightful discussion of possible functions of persistent spontaneous connectivity during unconsciousness in the spinal cord including latent activity in spinal central pattern generators or ongoing activity of circuits involved in maintenance/regulation of physiological processes under anesthesia.

      Weaknesses of the experimental approach and for potential functional interpretations include (1) the need for more elaboration of technical details about how the temporal correlations of neuronal activity was performed, and (2) electrophysiological measurements were confined to a single lumbar spinal segment, so that origins of the spontaneous activity including interactions between spinal and supraspinal regions, interactions between various spinal segments, and contributions of sensory afferent feedback despite anesthesia, could not be established. While attributing the patterns of spontaneous activity found to reflect intrinsic spinal circuit activity, the authors did not fully explore possible contributions of sensory afferent feedback, for example, by employing local deafferentation.

      The results presented in general suggest spontaneous temporally correlated neural activity in the spinal cord during unconsciousness, consistent with the concept that such activity may be a general property of central nervous system circuits.

    1. Reviewer #3 (Public Review):

      Wodeyar et al. suggest a new method for estimating the phase of oscillatory signals in real-time, based on a state-space objective. They test their approach in simulations and data and present evidence for higher accuracy compared to standard methods based on band-pass filtering. While I especially find the possibility of credible intervals highly interesting in this context, the relationship of credible intervals to an amplitude criterion threshold criterion, customary employed by standard approaches should be elucidated more, it's not clear to whether this practically results in very similar outcomes. In addition, it would be good to see clarifications on the underlying data generating process and physiological motivation for the provided simulations. It would increase accessibility of the manuscript, if the text would be more self-contained & more methodological details were included.

    1. Reviewer #3 (Public Review):

      The authors effectively utilized Beta5T-iCre to specifically manipulate beta-catenin expression in TECs and definitively showed that careful control of beta-catenin within TECs is needed for the proper development of TEC microenvironments critical for T cell development.

      Strengths:

      1) The methods used allowed the authors to effectively targeted TECs while avoiding extrathymic side effects of manipulating beta-catenin in ways that impacted skin or other tissues leading to abortive development or improper separation of the thymus and parathyroid.

      2) The results showed that beta-catenin GOF specifically in TECs results in thymic dysplasia and loss of thymic T cell development.

      3) The results from the analysis of beta-catenin LOF indicate that beta-catenin in TECs is not essential for the generation of functional TECs that support T cell development but the loss of beta-catenin in TECs results in the reduction in the number of cTECs, which leads to the reduction in the number of thymocytes during the postnatal period.

      4) The results demonstrated that GOF of beta-catenin in TECs results in trans-differentiation of TECs into terminally differentiated keratinocytes.

      Weakness:

      The fact that beta5T expression is restricted primarily to cTECs suggests that the models used may not accurately capture the impacts of gain of function and loss of function of beta-catenin to mTECs and the maintenance of the medulla in postnatal mice. Given that beta5T-expressing cells have been shown to give rise to both cTECs and mTECs during fetal development the models may more closely demonstrate the importance of fine-tuning beta-catenin expression during fetal development while missing impacts on postnatal mTECs.

      The authors achieved their aims and the results strongly support their conclusions.

      The work clearly demonstrates the importance of proper regulation of Wnt/beta-catenin signaling in the development and maintenance of TEC microenvironments and should lead to more interest in defining the specific Wnts and Frizzleds that are important in the development and postnatal maintenance of specific TEC subsets. This work will be important in identifying clinical strategies to counteract thymic involution and the subsequent loss of T cell function.

    1. Reviewer #3 (Public Review):

      The manuscript by Xiang and Bartel explores the molecular coupling of poly(A) tail length and translational efficiency (TE) in frog oocytes and various mammalian cell lines. From their experiments they draw several broad conclusions. Firstly, it is that limiting amounts of PABPC in frog oocytes is the basis for coupling between poly(A) tail length and TE. Secondly, in mammalian somatic cell lines PABPC contributes little to TE and transcript with TUT4 and TUT7-mediated uridylation promoting degradation of transcript with short poly(A) tails. Overall, the experimental design is excellent. The conclusions drawn from the frog oocytes are strongly supported by the data provided whereas the cell line studies are more open to interpretation due to the drastic consequences of PABPC depletion.

    1. Reviewer #3 (Public Review):

      Ma et al investigate the effect of racial and ethnic differences in SARS-CoV-2 infection risk on the herd immunity threshold of each group. Using New York City and Long Island as model settings, they construct a race/ethnicity-structured SEIR model. Differential risk between racial and ethnic groups was parameterized by fitting each model to local seroprevalence data stratified demographically. The authors find that when herd immunity is reached, cumulative incidence varies by more than two fold between ethnic groups, at approximately 75% of Hispanics or Latinos and only 30% of non-Hispanic Whites.

      This result was robust to changing assumptions about the source of racial and ethnic disparities. The authors considered differences in disease susceptibility, exposure levels, as well as a census-driven model of assortative mixing. These results show the fundamentally inequitable outcome of achieving herd immunity in an unmitigated epidemic.

      The authors have only considered an unmitigated epidemic, without any social distancing, quarantine, masking, or vaccination. If herd immunity is achieved via one of these methods, particularly vaccination, the disparities may be mitigated somewhat but still exist. This will be an important question for epidemiologists and public health officials to consider throughout the vaccine rollout.

    1. Reviewer #3 (Public Review):

      In this work, Chattaraj and colleagues utilize simulation models to study collective behaviors of molecules with multiple binding sites (multivalency). When the concentrations are low, the molecules do not bind to each other frequently, and they are called free. On the other hand, if the concentrations increase, they start to bind and eventually form a wide network of molecules connected by molecular binding. This transition can be considered as a model for liquid-liquid phase separation. Their major claim is that the solubility product, a simple product of the concentrations of the free molecules, can be used as a proxy to the phase separation threshold (known as the saturation concentration). They observed in various simulation conditions that as the total concentration of molecules increases, the solubility product first increases but eventually converges to a certain value, and the value is consistent over different simulation conditions. The value is the upper limit of the solubility product, after which the molecules start to form a molecular network.

      After establishing the model, they tested systems with different valences. Higher valency leads to reduction of the threshold (and phase separation occurs at lower concentrations). The theory was also valid for systems with non-equal valences (e.g. pentavalent A + trivalent B). They applied their models to a three-component system, and found that the results qualitatively explain the published experimental patterns. Lastly, using off-lattice coarse-grained simulations, they show that the linker flexibility and the spacing of binding sites are important determinants of the threshold, which confirms the findings from other computational and experimental works.

      The authors successfully defend their claim by using different types of simulations, and their methods to crosscheck the physical validity of their models may be useful for other simulation works. For example, the authors checked if increasing the number of molecules and reducing the system size give the same results for equal concentrations. Also, they employed two different methods (so-called FTC and CMC in the manuscript) to determine the threshold concentrations. However, the conclusions are not easily transferable to real biopolymer systems, since it is hard to determine the valences (and binding affinities) of biopolymers such as intrinsically disordered proteins.

    1. Reviewer #3 (Public Review):

      This study sought to identify essential features of ESCRT-III subunits, with a focus on the yeast proteins Vps2 and Vps24, in order to reveal the required features of both subunits. The combined genetic and biochemical studies solidified the model that essential functions of ESCRT-III polymers - spiral formation, lateral association, and binding of Vps4 - are mostly distributed between different subunits (with some redundancy) and can be engineered into a single polypeptide. This study also sheds light on the long-standing and initially surprising finding that ESCRT-dependent budding of HIV does not require CHMP3 (Vps24), presumably because the distribution of distinct functions between different ESCRT-III subunits is not absolute.

      Inspired by earlier studies, the ability of overexpression of one ESCRT-III subunit to compensate for deletion of another subunit was explored using sorting assays. The demonstration of partial rescue inspired a mutagenesis approach that identified three residues that cluster on one face of a helix that enhanced rescue, and therefore confer functionality that in wt is primarily provided in the deleted subunits, which in this case is binding to Snf7. Extension of this analysis by protein engineering further demonstrated that the essential role of recruiting the Vps4 ATPase is normally performed by Vps2 but can be transferred to Vps24 by substitution of residues near the ESCRT-III subunit C-terminus. Similarly, it is shown that sequences that alter the propensity for bending of a helix at a point where open and closed ESCRT-III subunits differ in conformation contributed to the ability of Vps24 to substitute for deletion of Vps2, presumably by conferring the ability to adopt the open, activated conformation as well as the closed conformation.

      I don't have concerns about design or technical aspects of the experimental approach.

    1. Reviewer #3 (Public Review):

      Maltese et al performed 2p imaging of both dSPNs and iSPNs at the same time, while focusing on correlates of forward locomotion. The modulation of dSPN ensembles in response to DA agonism or antagonism was mostly consistent with classic models, although they also observed an 'inverted U-shape' response to D1R agonsists. In addition, they found distinct modulation of dSPN and iSPN ensembles in DA-intact and Parkinsonian mice.

    1. Reviewer #3 (Public Review):

      Mark and colleagues set out to examine the relationship between neuronal targeting and connectivity and the developmental history of neurons. Specifically, the authors examine if, how and to what extent hemilineage identity combined with temporal birth order can explain neuronal connectivity. To this end they use the fly larval nerve cord with its EM-level resolution of connectivity and prior knowledge about hemilineage identity and birth order as a model.

      General comments:

      The manuscript represents a comprehensive, thorough and deep analysis of the system. The descriptive elements are outstanding, and the analysis of how Notch activity correlates with hemilineage targeting is of great interest. While understanding the relationship between connectivity diagrams and developmental history, including the role of Notch signaling, is not new, the scale of the analysis presented here is key because it allows - in principle - the drawing of general conclusions. The main "weakness" of the manuscript is not in the work itself but rather some of the key conclusions drawn from the data which often somewhat beyond what the data alone would support, especially in terms of the developmental mechanisms involved in establishing connectivity. With one partial exception (Notch gain of function experiments), the work essentially represents (very important) correlation analysis between the various parameters. While the authors are of course free to interpret their data as per their own views and biases, they do need to either tone down their, often categorical, statements and soften their conclusions, or perform further analysis to examine whether some of the stronger conclusions they draw are justified.

      Specific comments:

      1) Figure 1; page 3: The authors refer to the "striking" similarity between EM reconstructions and GFP filled clones and yet there are clear differences in some of the clones in the extent and localization of arborization. This may be in part technical but almost certainly also reflects inter individual differences in single neuron morphology. Since EM reconstructions presumably come for, one animal, the use of GFP clones allows the authors to map the degree of variation between clones and it would be interesting for them to show this.

      2) Figures 2 and 4; pages 3-5: Along the same lines as above, the authors make categorical statements about the mapping of arbors to dorsal and ventral regions of the nerve cord and correlate that to hemilineage identity. Again, there is clear mixing in almost all neuroblast lineages, that seems to range from 15-30% as a rough estimate, and perhaps a bit more dorsally than ventrally, which the authors do not comment on (except to say it's "mostly non-overlapping"). This is a pity because they obviously have the tools to do so quantitatively and the information is already there in their data.

      3) The analysis of Notch activity in hemilineages is excellent and very interesting, as is the new tool they develop. However, the analysis lacks loss of Notch function data and where and when Notch signaling is required to segregate the connectivity space (i.e. in neurons or in precursors such as Nbs and GMCs). Is this a binary fate specification mechanism or lateral inhibition among competing neurons? What about Notch activity manipulation in single neurons? If the authors wish to draw strong conclusions about the role of Notch in segregating target space and its relation to hemilineage identity, these experiments are essential. Alternatively, drawing subtler conclusions and acknowledging these caveats would be very welcome.

      4) Figure 7; Page 7: The authors state that 75% of hemilineage neurons correlated by temporal identity are separated by 2 synapses or less, suggesting greater connectivity than expected. How are these data normalized? What is the expected connectivity between neurons that are less related along these two developmental axes?

      5) Figure 8; page 7 and discussion: The authors conclude that the combination between temporal identity and hemilineage identity predicts connectivity beyond what would be predicted by spatial proximity alone. This conclusion is problematic at least two levels. First, practically what really matters for proximity is proximity during the time in development when synapses are forming between neuronal pairs, not proximity at the end in the final pattern. Second, conceptually, opposing spatio-temporal mechanisms with proximity-based bias for connectivity makes no sense because that's exactly what spatio-temporal mechanisms achieve: getting neurons to the same space at the same time so connectivity can happen. At any rate, drawing strong conclusions about where and when neurons meet to form (or not form) synapses requires live imaging and absent that authors should refrain from making such a string statement about what their excellent correlative dataset means.

    1. Reviewer #3 (Public Review):

      In this manuscript Lituma and colleagues investigate a potential role for presynaptic NMDARs at hippocampal mossy fiber (MF) synapses in regulating synaptic transmission. The combined use of electron microscopy, electrophysiology, optogenetics, calcium imaging, and genetic manipulations expertly employed by the authors yields high quality compelling evidence that presynaptic NMDARs can participate in activity dependent short term facilitation of release onto postsynaptic CA3 pyramid and mossy cell targets but not onto inhibitory interneurons. Moreover, presynaptic NMDAR activation is demonstrated to be particularly effective in promoting BDNF release from MF boutons. The investigation is well designed with a clear hypothesis, appropriate methodological considerations, and logical flow yielding results that fully support he authors conclusions. The manuscript fills an important gap in our understanding of MF regulation by unambiguously confirming a functional role for presynaptic NMDARs that were first described anatomically at MF terminals nearly 30 years ago. Combined with a handful of other studies describing presynaptic NMDARs at various central synapses this study expands the role of NMDARs as critical players in synaptic plasticity on both sides of the cleft.