The Neural Crest Cell Lineage Problem: Neuropoiesis?

The neural crest is a remarkable invention of vertebrate embryogenesis. It consists of a population of precursor cells that detaches from the apical neural tube and then rapidly disperses into the embryo along complex pathways of migration. The proliferating crest cells arrest their migration in various locales where they aggregate to form the sensory and autonomic ganglia of the peripheral nervous system. Neural crest cells also invade developing tissues such as the skin, gut, and adrenal gland to generate differentiated cell populations within these tissues, e.g., melanocytes, enteric neurons, and adrenal medullary chromaffin cells, respectively. The diversity of the cell types derived from the neural crest (Table 1) poses the problem of how uncommitted embryonic cells acquire particular developmental fates