Summary: This Primer gives an overview of Xenopus as a model system for studying regeneration, comparing the two species X. laevis and X. tropicalis, and highlighting how Xenopus studies have enhanced our understanding of the molecular mechanisms of regeneration.
STEM CELLS AND REGENERATION
A coherent feed-forward loop drives vascular regeneration in damaged aerial organs of plants growing in a normal developmental context
Highlighted Article: The PLT-CUC2 module acts in a feed-forward loop to increase the local auxin biosynthesis at the wound site. This drives vascular regeneration in aerial organs of plants.
Highlighted Article: Maternal age-induced epigenetic changes in the uterus interfere with the induction of decidualisation genes, and thereby impede the early gestational adaptations that are essential for a successful pregnancy.
Summary: Left-right asymmetric neurogenesis of the vertebrate habenula depends on tight control of Wnt/β-catenin signaling involving a Wif1-mediated regulatory feedback loop.
Summary: Post-translational monoubiquitylation modification of key transcription factors plays a vital role in regulation of noradrenergic neuron development.
Canonical Wnt/β-catenin activity and differential epigenetic marks direct sexually dimorphic regulation of Irx3 and Irx5 in developing mouse gonads
Summary: Differential occupation of two enhancers defines sex-specific regulation of Irx3 and Irx5 in fetal gonads: repressor marks inhibit in testes, while active marks engage with β-catenin/TCF to stimulate in ovaries.
Highlighted Article: A multicellular model of auxin transport in the Arabidopsis root tip reveals the importance of intercellular plasmodesmata in maintaining auxin pattern and fluxes.
Summary: The evolution of serrations at the leaf margin requires a fine tuning of cell growth; the transcription factor CUC3 is crucial for maintaining local and transient repression of growth in a few sinus cells.
CXXC finger protein 1-mediated histone H3 lysine-4 trimethylation is essential for proper meiotic crossover formation in mice
Summary: Conditional knockout of Cxxc1 in mouse pre-meiotic germ cells led to a decrease in H3K4me3, dysregulation of crossover formation and meiotic arrest, revealing an essential role for CXXC1 in spermatogenesis and oogenesis.
Expression of E93 provides an instructive cue to control dynamic enhancer activity and chromatin accessibility during development
Summary: The temporal transcription factor E93 controls both activation and deactivation of different target enhancers in the same cells to respond to spatial cues through regulation of chromatin accessibility.
Summary: Maintaining actin dynamics is crucial for cell motility. Post-transcriptional regulation plays a pivotal role in supporting actin dynamics during neuronal migration.
TECHNIQUES AND RESOURCES
Highlighted Article: Transcriptional, signaling and cellular programs governing pig pancreatic islet development exhibit striking similarities to human islet ontogeny, providing a novel resource for advancing human islet replacement strategies.
Summary: A single cell transcriptome at three stages of zebrafish hindbrain development provides a valuable resource for investigations of the patterning of neurogenesis and transition of progenitors to neuronal differentiation.