Developmental Biology

eLife Assessment

This useful study by Gao et al identifies Hspa2 as a heterogeneous transcript in the early embryo and proposes a plausible mechanism showing interactions with Carm1. The authors propose that variability in HSPA2 levels among blastomeres at the 4-cell stage skews their relative contribution to the embryonic lineage. Given only 4 other heterogeneous transcripts/non-coding RNA have been proposed to act similarly at or before the 4-cell stage, this would be a key addition to our understanding of how the first cell fate decision is made. While this is a solid study, further data are needed to fully support the conclusions.

eLife Assessment

This study presents important insights into the regulation of left-right organ formation. By combining genetic perturbation of all three Meteorin genes in zebrafish and timelapse imaging, the authors identify an essential role for this protein family in the establishment of left-right patterning. They provide convincing evidence that Meteorins are required for the morphogenesis of dorsal forerunner cells, the precursors of the left-right organizer (also named Kupffer's vesicle) in zebrafish. In line with this, Meteorins were shown to genetically interact with integrins ItgaV and Itgb1b to regulate dorsal forerunner cell clustering.

eLife Assessment

This manuscript describes a resource detailing the econstitution of Holothuria glaberrima gut following self-evisceration in response to a potassium chloride injection, using scRNAseq and fluorescent RNA localization in situ. It provides some new findings about organ regeneration, as well as the origins of pluripotent cells, and places these findings in the context of regeneration across species. The paper's schematic model and HCR images are a valuable foundation for future work. The authors provide convincing RNA localization images to validate their data and to provide spatial context. These validation experiments are of good quality but remain challenging to connect to the complex spatial organization of complex tissues. This resource will be of interest to the field of regeneration, particularly in invertebrates, but also in comparative studies in other species, including evolutionary studies.

eLife Assessment

This valuable study reports on the critical role of ANKRD5 (ANKEF1) in sperm motility and male fertility. However, the supporting data remain incomplete. This work will be of interest to biomedical researchers working in sperm biology and andrologists.

eLife Assessment

This fundamental article significantly advances our understanding of FGF signalling, and in particular, highlights the complex modifications affecting this pathway. The evidence for the authors' claims is convincing, combining state-of-the-art conditional gene deletion in the mouse lens with histological and molecular approaches. This work should be of great interest to molecular and developmental biologists beyond the lens community.

eLife Assessment

This manuscript establishes a mathematical model to estimate the key parameters that control the repopulation of planarian stem cells after sublethal irradiation as they undergo fate-switching as part of their differentiation and self-renewal process. The findings are important for future investigation of stem cell division in planarians and have implications for analyzing stem cell biology in other systems. The methods are convincing, integrating modeling with perturbations of key transcription factors known to be critical for cell fate decisions, but the authors have only shown that this is the case for a small number of stem cell types.

eLife Assessment

This important study examines the role of pericytes in patterning the zebrafish blood-brain barrier (BBB) and controlling its permeability. Using pdgfrb mutant zebrafish models lacking brain pericytes, the authors report that pericyte-deficient cerebrovasculatures are ill-patterned, yet display unaltered restrictive BBB permeability properties at larval and juvenile stages. More severe phenotypes are detected in adults, with focal leakage sites associated with hemorrhages and aneurysms. Using solid and beautifully documented imaging, the authors suggest that, contrary to the situation described in rodent models, pdgfrb-dependent pericytes are not required to maintain the BBB in the zebrafish brain; these unexpected and intriguing findings reshape our understanding of BBB permeability regulation in vertebrates.

eLife Assessment

This valuable work presents how PRDM16 plays a critical role during colloid plexus development, through regulating BMP signaling. Solid evidence supports the context-dependent gene regulatory mechanisms both in vivo and in vitro. The work will be of broad interest to researchers working on growth factor signaling mechanisms and vertebrate development.

eLife Assessment

In this important study, the authors test the model that a type of vascular lesion caused by the inactivation of one gene in the cells that line blood vessels requires the activity of a second gene for the lesions to form. The evidence supporting the conclusions is solid.

eLife Assessment

This comprehensive scRNAseq atlas of the cranial region during neural induction, patterning, and morphogenesis provides a fundamental demonstration of how different cell fates are organized in specific spatial patterns along the anterior-posterior and medial-lateral axes within the developing neural tissue. The compelling data are analyzed with a rigorous computational approach, and the data revealed both known and novel genes differentially expressed along rostro-caudal and medio-lateral axes. This will be a helpful resource for researchers studying brain development.