Evaluation statement (1 September 2023)
Flores-Aldama and colleagues set out to identify molecular determinants of fast inactivation in the TRPV6 ion channel, a mechanism not observed in the closely related TRPV5 channel. The work focuses on a helix-loop-helix (HLH) motif, located at the interface between several important regions for channel gating. Using molecular dynamics simulations and analysis of mutations, the authors identify pairs of amino acid residues in a structural triad formed by the HLH, S2-S3 linker, and transmembrane domains, which show different conformations in the available TRPV5 and TRPV6 cryo-EM structures. An important aspect of the study is that some of the structural hypotheses were derived from an evolutionary analysis of sequences from orthologues of both channels, demonstrating the value of this type of analysis.
Biophysics Colab considers this to be a convincing study and recommends it to scientists interested in the molecular determinants of ion channel gating.
(This evaluation by Biophysics Colab refers to the version of record for this work, which is linked to and has been revised from the original preprint following peer review.)