Sleep or deplete: how the choroid plexus helps to keep neural stem cells in balance.

The activity of stem cells in the adult brain is controlled by various niche-dependent mechanisms. A new article by Lepko et al (2019) shows that proliferation of neural stem cells in the ventricular-subventricular zone is regulated by choroid plexus-derived miR-204, identifying a novel mechanism of how the delicate balance between stem cell quiescence and activation is controlled.