Bases moleculares del desarrollo de la cresta neural troncal

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 25-02-2011SUMMARY The coordination of adjacent tissues that establish functional relationships is essential during embryonic development. Formation of neural crest cells at the trunk level is highly influenced by the development of the adjacent mesoderm. However, the molecular mechanism involved is not well understood. FGF and retinoic acid mesodermal signaling gradients control de onset of neurogenesis in the extending neural tube. In this project, using gain and loss of function experiments in chicken embryos, we have determined that the caudal gradient of FGF signaling prevents premature specification of neural crest cells and consequently premature neural crest cell delamination. By contrast, retinoic acid rostral gradient promotes delamination of neural crest cells at somitic levels. Moreover, we have established that the time of delamination determines the migratory behavior of the neural crest cells. These data establish a clear role of FGF and retinoic acid mesodermal gradients in controlling the timing of neural crest cell delamination and consequently coordinating the development of central and peripheral nervous system during vertebrate trunk elongation