Summary: This Spotlight highlights how recent advances in imaging technologies have enabled stem cells to be visualised in real time within intact organ systems, revealing novel aspects of their behaviour, especially in response to injury.
Summary: A historical and current account of comparative studies providing insight into the epicardium during heart development and regeneration: origins, formation, cell fate, signalling activity, interaction with the local environment and therapeutic potential.
STEM CELLS AND REGENERATION
Summary: Drosophila type II NBs are generated in three clusters during stage 12 of embryogenesis, the specification of which requires the combined action of the EGFR pathway, buttonhead and Sp1.
Diet regulates membrane extension and survival of niche escort cells for germline homeostasis via insulin signaling
Summary: Insulin signaling mediates dietary effects to maintain escort cell cellular protrusion and survival for Drosophila ovarian germline stem cell maintenance and soma-germline interactions.
PDGF-A signaling is required for secondary alveolar septation and controls epithelial proliferation in the developing lung
Summary: PDGF-A is needed during alveolar formation in the lung to promote migration and proliferation of myofibroblasts and to control the growth of alveolar epithelial type II cells.
Summary: The E3 ubiquitin ligase March2 and the Dsh-interacting protein Dapper1 cooperatively regulate turnover of Dsh via lysosomal degradation to antagonize Wnt signaling and contribute to Xenopus head formation.
Evolutionary divergence of the sex-determining gene MID uncoupled from the transition to anisogamy in volvocine algae
Highlighted Article: Mid from both anisogamous (Pleodorina) and isogamous (Gonium) volvocine genera can activate spermatogenesis when expressed in Volvox females, indicating that changes unrelated to Mid underlie the evolution of gamete dimorphism.
The mir-279/996 cluster represses receptor tyrosine kinase signaling to determine cell fates in the Drosophila eye
Summary: miR-279/996 are deployed in non-neuronal cells of the developing Drosophila eye to restrict RTK/Ras signaling and directly target the rho, ru and boss 3′ UTRs, with miR-279/996 loss yielding ectopic R7 photoreceptors and cone cell depletion.
Disrupting the three-dimensional regulatory topology of the Pitx1 locus results in overtly normal development
Summary: Long-range regulatory interactions may have limited predictive value for identifying enhancer mutations with strong loss-of-function phenotypes during development.
Highlighted Article: The trithorax group protein Ash1 and its regulator MRG15 form a multiprotein complex that maintains expression of HOX and other target genes by methylating histone H3 in their chromatin.
Evolutionarily conserved anterior expansion of the central nervous system promoted by a common PcG-Hox program
Summary: In both Drosophila and mouse, anterior CNS expansion results from proliferation differences between brain and nerve cord, and is controlled by the PcG-Hox regulatory program.
Conserved functional control, but distinct regulation, of cell proliferation in rice and Arabidopsis leaves revealed by comparative analysis of GRF-INTERACTING FACTOR 1 orthologs
Summary: The orthologous rice and Arabidopsis genes MKB3 and AN3 have mostly conserved functions in leaf development but their expression pattern and the direction of movement of the proteins they encode differ.
Highlighted Article: Characterization of the developmental defects of l(3)mbt mutant ovaries shows that L(3)mbt regulates tissue-specific gene signatures to secure the identity of somatic ovarian and germline tissues.
Polycomb group (PcG) proteins and Pax6 cooperate to inhibit in vivo reprogramming of the developing Drosophila eye
Highlighted Article: The molecular events underlying the eye-to-wing transdetermination described by Hadorn in 1968 reveal the roles of Pax6 and PcG proteins.
Summary: The metalloproteinase ADAM19 non-proteolytically interacts with ADAM13 and inhibits ADAM13 turnover to regulate Wnt signaling snail2 expression and neural crest specification in Xenopus.
The heart tube forms and elongates through dynamic cell rearrangement coordinated with foregut extension
Summary: Cell cluster labeling and live imaging reveal that the flat heart primordia remodel into the rapidly elongating tube through dynamic tissue reshaping, driven by oriented-cell rearrangement, coordinately with foregut formation.
Imprinted gene dysregulation in a Tet1 null mouse model is stochastic and variable in the germline and offspring
Summary: Methylcytosine dioxygenase TET1 is a key regulator of imprinting in both the maternal and paternal lineages, with loss resulting in hypermethylation of KvDMR, Peg1 and Peg3 ICRs in sperm and of IG-DMR and H19/Igf2 ICRs in oocytes.
PUF-8 facilitates homologous chromosome pairing by promoting proteasome activity during meiotic entry in C. elegans
Summary: C. elegans mutants of the RNA-binding protein PUF-8 and the α1 proteasome subunit PAS-1 show meiotic defects and sterility that are due at least in part to increased activity of the axis component HTP-3 in premeiotic cells of the germline.
TECHNIQUES AND RESOURCES
Summary: Application of FAIRE-seq chromatin profiling to T. castaneum and the establishment of a cross-species-compatible universal reporter assay system facilitates investigation of cis-evolution and morphological diversity in Tribolium and other insects.
Summary: eMOSS, a new, freely available online tool (limbstaging.embl.es), enables fast and reliable determination of the developmental age of mouse embryos based on two-dimensional images of their limb buds.
Genome-wide strategies identify downstream target genes of chick connective tissue-associated transcription factors
Summary: Global profiling of five transcription factors associated with connective tissue subtypes reveals molecular signatures regulated during limb development and provides a data resource for future studies of connective tissue formation.