Neuroprogenitors dispense life and death

Normal embryonic brain development is dependent upon tight regulation of neural stem cell differentiation as well as proliferation. Uncontrolled alteration of the numbers of neural stem cells results in hyperproliferation of brain tissue and in subsequent deleterious effects on the development of the nervous system. Regulation of cell number is achieved by a number of mechanisms—including programmed cell death (apoptosis)—and, in this case, when neural progenitor cells divide, only one progeny cell survives. In the July 28 Journal of Cell Biology, Erhard Bieberich and colleagues at the Medical College of Georgia have identified the stimuli that regulate cell death and survival in neural stem cells (Journal of Cell Biology, DOI:10.1083/jcb.200212067, July 28, 2003).

Bieberich et al. hypothesized that since apoptosis of neuronal stem cells follows soon after cell division, this may result from the unequal distribution of pro- and antiapoptotic factors to the daughter cells...