Table of Contents
IN THIS ISSUE
- An interview with Jayaraj Rajagopal
Summary: Jayaraj Rajagopal, winner of the ISSCR's Susan Lim Young Investigator Award, discusses his transition from the bedside to the bench and his optimism for basic research and its translation.
- On the evolution of bilaterality
Summary: This Hypothesis evaluates various theories of the evolutionary emergence of animal bilaterality, based on what we have learnt from early branching animal clades, especially from Cnidaria.
- The PAR proteins: from molecular circuits to dynamic self-stabilizing cell polarity
Summary: This Review discusses studies that have revealed how the PAR protein network can form and stabilize the asymmetric distribution of its components.
- Can injured adult CNS axons regenerate by recapitulating development?
Summary: This Review highlights the mechanisms underlying CNS developmental axon growth and adult regeneration failure, exploring the hypothesis that adult central neurons can regenerate by recapitulating development.
- Spermatogonial kinetics in humans
Summary: Marker protein expression pattern analysis improves understanding of human spermatogonial development and stem cell renewal, facilitating further research and providing insight into fertility problems.
STEM CELLS AND REGENERATION
- Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians
Highlighted Article: snail-1, snail-2 and zeb-1 control precise homing of stem cells and their progeny to wound sites, whereas the polarity determinant notum controls migration in the absence of wounding to maintain anterior tissue homeostasis.
- Imp and Syp RNA-binding proteins govern decommissioning of Drosophila neural stem cells
Highlighted Article: Temporal progression of Imp/Syp gradients determines the timing of neuroblast decommissioning and cell cycle exit in addition to progeny temporal fate, allowing proper completion of a neuronal lineage.
- Differential interactions between Notch and ID factors control neurogenesis by modulating Hes factor autoregulation
Summary: Computational analysis of transcriptome data from neural stem cells reveals key differences in the synergistic interactions between Notch and inhibitor of DNA-binding factors during embryonic and adult neurogenesis.
- DNA damage induces a kinetochore-based ATM/ATR-independent SAC arrest unique to the first meiotic division in mouse oocytes
Highlighted Article: DNA damage in MI oocytes causes rapid recruitment and activation of spindle assembly checkpoint proteins at kinetochores leading to cell cycle arrest, thereby preventing the propagation of damaged chromatin.
- Heart morphogenesis gene regulatory networks revealed by temporal expression analysis
Summary: Transcriptome profiling during zebrafish heart looping reveals novel and evolutionarily conserved gene regulatory networks and cohorts of genes with shared temporal and spatial regulation.
- Notum coordinates synapse development via extracellular regulation of Wingless trans-synaptic signaling
Summary: Extracellular enzymatic deacylase regulation of Wnt trans-synaptic signaling in Drosophila is crucial for proper structural, ultrastructural and functional development of the neuromuscular synapses underlying coordinated movement.
- Afadin orients cell division to position the tubule lumen in developing renal tubules
Summary: In vitro and in vivo studies reveal that the F-actin-binding protein afadin ensures lumen continuity in developing renal nephrons by orienting the mitotic spindle perpendicular to the apical-basal axis during cell division.
- Adenohypophysis placodal precursors exhibit distinctive features within the rostral preplacodal ectoderm
Summary: In chick embryos, adenohypophyseal placode precursors differ from the remaining preplacodal ectoderm as they are clustered at the midline, resembling other midline structures important for maintaining the bilateral organization of the neural tube.
- An essential role for IGF2 in cartilage development and glucose metabolism during postnatal long bone growth
Summary: Attenuation of glucose consumption in Igf2 null mice rescued the mutant phenotype of premature cartilage maturation, revealing that IGF2 controls cartilage development in part by regulating glucose metabolism in chondrocytes.
- HOXA5 plays tissue-specific roles in the developing respiratory system
Summary: Characterization of Hoxa5 conditional mutant mice establishes that Hoxa5 regulates respiratory system development through distinct mechanisms in epithelium, mesenchyme and phrenic motor neurons.
- miR-322 stabilizes MEK1 expression to inhibit RAF/MEK/ERK pathway activation in cartilage
Summary: miR-322 is identified as an unconventional inhibitor of a central signaling pathway in mouse chondrocytes that regulates transient and permanent cartilage homeostasis through MEK1 production and suppression of ERK1/2 phosphorylation
- Perturbing phosphoinositide homeostasis oppositely affects vascular differentiation in Arabidopsis thaliana roots
Summary: Disturbance of the optimal ratio of PtdIns(4,5)P2 and PtdIns4P has opposing effects on vascular differentiation due to the distinct role of vacuolar biogenesis in their differentiation programs.
- Smooth muscle cell recruitment to lymphatic vessels requires PDGFB and impacts vessel size but not identity
Summary: Pdgfb mutant mice provide insight into the recruitment and function of smooth muscle cells in the lymphatic vasculature, and shed new light on mechanisms of lymph vessel-associated diseases.
- Notch signaling patterns neurogenic ectoderm and regulates the asymmetric division of neural progenitors in sea urchin embryos
Summary: Notch regulates the recruitment of SoxC-expressing neural progenitors by lateral inhibition and triggers apoptosis to determine which of the progeny of the final mitosis will become a neuron.
TECHNIQUES AND RESOURCES
- A fixation method to preserve cultured cell cytonemes facilitates mechanistic interrogation of morphogen transport
Summary: A new fixation method for preserving cultured cell cytonemes, used in combination with live cell imaging, reveals that the Hedgehog deployment protein Dispatched promotes cytoneme occurrence by slowing retraction rates.
- Psychrophilic proteases dramatically reduce single-cell RNA-seq artifacts: a molecular atlas of kidney development
Summary: A new method using a protease that works in the cold for cell dissociation dramatically reduces single-cell RNA-seq artifacts, allowing more accurate determination of gene expression in the newborn mouse kidney.