Jessica Ann Billet and Andy Nichols, Franklin and Marshall College, 2000

Background

The neural crest, in vertebrates, is a transient embryonic structure which gives rise to a multitude of cell types. These include most of the peripheral nervous system, endocrine cells, glia, and melanocytes (Henion, 1994 ; Murphy, 1994).

There is evidence that individual NC (neural crest) cells are initially multipotent but, over time, they lose their ability to differentiate into the full range of NC cell types (Murphy, 1994). NC cells migrate from the neural tube into discrete regions of the embryo where proliferation and differentiation is regulated by factors in the microenvironment (Murphy, 1994).

As stated above, the NC cell pathway is not cell-autonomous, but is regulated by the microenvironment. The developmental fate of NC cells is also determined by the pathway of NC cell migration. NC cells that migrate early on the ventral pathway into the somite give rise to sensory and sympathetic neurons, whereas the crest cells that undergo delayed migration on the lateral pathway produce only pigment cells (Marusich, 1991).