Hedgehog signaling and the primary cilium: implications for spatial and temporal constraints on signaling
Summary: This Review synthesizes current understanding of Hedgehog signal transduction, ligand secretion and transport, and cilia dynamics to explore the temporal and spatial constraints imposed by the primary cilium on Hedgehog signaling in vivo.
Summary: This Review discusses application of the emerging CRISPR toolbox toward predicting gene regulatory network behavior, improving stem cell disease modeling, dissecting the epigenetic code, reprogramming cell fate and treating diseases of gene dysregulation.
STEM CELLS AND REGENERATION
Proper timing of a quiescence period in precursor prospermatogonia is required for stem cell pool establishment in the male germline
Summary: Entry into mitotic arrest on an order development timeline is crucial for survival of prospermatogonia during fetal development and establishment of the spermatogenic lineage in postnatal life.
A multi-gene knockdown approach reveals a new role for Pax6 in controlling organ number in Drosophila
Summary: The simultaneous reduction of Pax6 with either the NURF nucleosome remodeling complex or the transcription factor Pointed reveals roles for these factors that cannot be discerned from removing each one individually.
Mathematical modeling of the interaction between yolk utilization and fish growth in zebrafish, Danio rerio
Summary: Mathematical modeling establishes a nonlinear functional relationship between nutrient absorption and early fish growth and identifies the hour post-fertilization at which yolk metabolism reaches its maximum.
The extracellular matrix protein agrin is essential for epicardial epithelial-to-mesenchymal transition during heart development
Summary: High-resolution imaging reveals epithelia-to-mesenchyme transition (EMT) heterogeneity on the surface of developing mouse hearts. Proteoglycan again regulates epicardial EMT through dystroglycan localising within the Golgi apparatus.
Environmental oxygen regulates astrocyte proliferation to guide angiogenesis during retinal development
Highlighted Article: Oxygen regulates proliferation of immature retinal astrocytes. Perturbing this mechanism inflates astrocyte numbers, disrupts retinal angiogenesis and leads to vascular pathologies resembling retinopathy of prematurity.
Highlighted Article: Live imaging of the chick embryo face followed by mathematical analysis of mesenchymal cell tracks captures novel fluctuations between states of order/disorder as well as symmetry/asymmetry, revealing developmental instabilities that are part of normal morphogenesis.
Highlighted Article: Quantitative measurements and simulations show that fluid-flow-induced shear stress drives biased elongating outgrowth of epithelial tubes in early lung and kidney development.
Cis-regulatory dissection of cone development reveals a broad role for Otx2 and Oc transcription factors
Summary: Genome-wide assays have led to the identification of many new cis-regulatory modules for genes important in cone development, showing that Otx2 and Oc have a broad role in this regulation.
Ret signaling in ureteric bud epithelial cells controls cell movements, cell clustering and bud formation
Highlighted Article: The forced expression of Ret causes ureteric bud cells to move to the branching tips in developing kidneys, and to form cell clusters, then new buds, in epithelial organoids.
Summary: Canonical WNT signaling is required for postnatal oocyte growth by supporting the activation of surrounding somatic cells in the mouse ovary.
Summary: During tooth morphogenesis, transient thickening of the epithelium in the diastema anterior to the first developing molar is an early signaling center, the molar initiation knot (IK), which is required for the progression of mammalian molar tooth development.
Eukaryotic initiation factor 4A3 inhibits Wnt/β-catenin signaling and regulates axis formation in zebrafish embryos
Summary: EIF4A3, a core component of exon junction complexes, inhibits Wnt/β-catenin signaling and regulates zebrafish axis formation by interfering with the formation of the β-catenin/Tcf transcription activation complex.
Highlighted Article: Embryonal carcinoma cells, the precursors of testicular germ cell tumors, upregulate MYC signaling pathways and arise exclusively from male germ cells that fail to initiate sex specification.