eLife assessment
This study presents valuable findings that will allow for a better understanding of the targets of SMAD and Schnurri, transcription factors that act downstream in the BMP signalling pathway. The evidence presented in this manuscript is solid, but because the claims of a SMA-3/SMA-9 complex are not experimentally supported, they should be toned down. Revising the discussion to give a broader context of BMP-driven body size control would help the readers put this work in a larger context. This work will be of broad interest to colleagues studying BMP signalling across phyla.