Summary: This Review highlights how studies on both males and females will lead to a more accurate and comprehensive understanding of development by illuminating new molecular, cellular, organ-level and organismal mechanisms.
Huntingtin CAG expansion impairs germ layer patterning in synthetic human 2D gastruloids through polarity defects
Highlighted Article: 2D gastruloids of isogenic human embryonic stem cells modeling Huntington's Disease reveal that huntingtin CAG expansion perturbs the spatial restriction of the activin response in the context of the polarized epithelium.
STEM CELLS AND REGENERATION
Prrx1b restricts fibrosis and promotes Nrg1-dependent cardiomyocyte proliferation during zebrafish heart regeneration
Highlighted Article: Epicardial-expressed Prrx1 ensures a balance between the fibrotic response and myocardial regeneration post-injury in zebrafish.
Summary: This study demonstrates novel and unique mechanisms underlying how stromal AR signaling facilitates Shh-mediated cell niches in pubertal prostatic epithelial growth and development.
PEG10 viral aspartic protease domain is essential for the maintenance of fetal capillary structure in the mouse placenta
Summary: Disruption of the highly conserved viral aspartic protease domain in PEG10 causes placental abnormality leading to perinatal lethality in mice.
Summary: Measuring Notch-dependent transcription in live embryos reveals that features associated with lateral membranes are required for initiation of Notch signalling. Perturbing membrane growth or adherens junctions prevents normal activation.
Shaking hands is a homeodomain transcription factor that controls axon outgrowth of central complex neurons in the insect model Tribolium
Summary: A detailed examination of the developmental expression of the homeodomain transcription factor Shaking hands in Tribolium reveals a role in the formation of the central complex primordium.
RH17 restricts reproductive fate and represses autonomous seed coat development in sexual Arabidopsis
Summary: Mutant alleles of the RNA helicase RH17 lead to phenotypes resembling elements of asexual reproduction through seeds (apomixis) in sexual Arabidopsis.
The Drosophila ribosome protein S5 paralog RpS5b promotes germ cell and follicle cell differentiation during oogenesis
Summary: Loss of germline-enriched RpS5b results in increased ribosome biogenesis and protein synthesis. However, RpS5b mutants display decreased translation of vitellogenesis and microtubule organization factors, resulting in egg chamber degeneration.
Gene-teratogen interactions influence the penetrance of birth defects by altering Hedgehog signaling strength
Highlighted Article: The MMM complex is a module that attenuates Hedgehog signaling, regulating left-right asymmetry of organs as well as patterning and morphogenesis of multiple tissues in the embryo.
Highlighted Article: The psychoactive cannabinoid THC inhibits Hedgehog signaling in genetically sensitized mouse embryos, consistent with a gene–environment interaction model for the etiology of a common birth defect.
Summary: Two different mouse models delineate the morphological and functional impact of Kpna6 on spermatogenesis and Sertoli cell function and show that this protein is crucial for fertility in male mice.
Summary: A transient transcriptional repressor is required in only one of three lineages that produce the same cell type.
Summary: A temporal study of sea urchin development captured using scRNA-seq. Gene expression during lineage trajectories matches known gene regulatory network changes, and demonstrates both synchronous and asynchronous lineage resolutions.
Tbx4 function during hindlimb development reveals a mechanism that explains the origins of proximal limb defects
Summary: Examination of the effects of loss of Tbx4 reveals molecular and cellular mechanisms underlying proximally biased limb defects, which could explain the origins of the congenital limb abnormality, phocomelia.
Redundant enhancers in the iab-5 domain cooperatively activate Abd-B in the A5 and A6 abdominal segments of Drosophila
Summary: In Drosophila, the segment-specific expression of the homeotic gene Abdominal-B in the abdominal segments is regulated by autonomous regulatory domains. We demonstrate cooperation between these domains in activation of Abdominal-B.
TECHNIQUES AND RESOURCES
Summary: A method exploiting the biallelic editing ability CRISPR-Cas9 to create maternal crispants enables the identification of maternal-effect genes in a single generation.
Summary: Generation of endogenously tagged stable zebrafish knock-in lines is simplified by the integration of fluorescent protein cassettes with mRNA splicing elements into non-coding regions of genes.