Cell-cycle exit

Here the authors show that differentiation of haematopoietic stem cells into mature blood cells is primed by cell type-specific transcription factors at the enhancer level during early differentiation, before they confere promoter-driven growth arrest, and activate post-mitotic terminal differentiation.

Rapid turnover and regeneration of intestinal epithelium requires distinct intestinal stem cell (ISC) populations. Here the authors show p57 marks quiescent ISCs, and that differentiated cells revert to stem cell state after injury, through dynamic reprogramming characterized by fetal- and metaplastic-like changes.

The mechanisms regulating mitosis and differentiation during development are thought to be distinct. Here they show that in Drosophila the mitotic kinase Polo regulates cellular morphogenesis after cell cycle exit.