Involvement of endothelin receptors in normal and pathological development of neural crest cells.

Endothelin receptors (Ednr) are G-protein-coupled receptors with seven membrane-spanning domains and are involved in various physiological processes in adults. We review here the function of these receptors during the development and transformation of the neural crest cell-specific lineage. Neural crest cells (NCC) may be classified according to their location in the body. In particular, there are clear differences between the neural crest cells arising from the cephalic part of the embryo and those arising from the vagal and truncal part. The development of cranial and cardiac NCC requires the endothelin-1/Ednra system to be fully functional whereas the development of more posterior NCC requires full functionality of the endothelin-3/Ednrb system. Mutations have been found in the genes corresponding to these systems in mammals. These mutations principally impair pigmentation and enteric ganglia development. The precise patterns of expression of these receptors and their ligands have been determined in avian and mammalian models. Data obtained in vitro and in vivo have provided insight into the roles of these proteins in cell proliferation, migration, differentiation and transformation.