The origin and development of glial cells in peripheral nerves.

During the development of peripheral nerves, neural crest cells generate myelinating and non-myelinating glial cells in a process that parallels gliogenesis from the germinal layers of the CNS. Unlike central gliogenesis, neural crest development involves a protracted embryonic phase devoted to the generation of, first, the Schwann cell precursor and then the immature Schwann cell, a cell whose fate as a myelinating or non-myelinating cell has yet to be determined. Embryonic nerves therefore offer a particular opportunity to analyse the early steps of gliogenesis from transient multipotent stem cells, and to understand how this process is integrated with organogenesis of peripheral nerves.