Death comes early: apoptosis observed in ENS precursors.

Cell death is a physiological and fundamental process in normal organogenesis. During the development of the nervous system, cell death or apoptosis occurs in early and late developmental time periods, affecting neural precursors and neurons respectively. In the development of the enteric nervous system (ENS), however, apoptosis of neurons has not been detected, a feature unique to enteric neurons. In this issue of Neurogastroenterology and Motility, Wallace et al. focused on an early phase of ENS development and identified apoptotic cell death in vagal neural crest cells, the primary cellular source for the ENS. Introduction of an antiapoptotic molecule in the vagal neural crest and its derivatives resulted in the overproduction of neurons in the foregut. Thus, unlike the neurons themselves, ENS precursors do undergo apoptosis, which may, by regulating the size of the ENS precursor pool, be a crucial factor in determining the final cell number in the ENS.