Patterning of the vertebrate neural crest.

The mechanisms underlying neural crest cell migration are beginning to be understood thanks to the ability to combine a number of techniques in experimental embryology, cell and molecular biology. In the trunk, cell-cell interactions may predominate, so that the mesodermal somites control the rostrocaudal patterning of neural crest cells and the notochord prevents neural crest cells from crossing the midline. In the hindbrain, the segmental migration of neural crest cells may be influenced both by information inherent to the rhombomeres coupled with environmental signals from neighboring tissues, such as the otic vesicle. There is clearly an intimate relationship between migrating neural crest cells, the neural tube from which they emerge, and tissues through which they move. All of these elements are integral in the control of neural crest migration.