The neural crest (NC) is a multipotent population of migratory cells unique to the vertebrate embryo. The NC is initially induced at the neural plate border. As the neural plate closes NC cells delaminate from the neuroepithelium and migrate throughout the embryo to give rise to a wide variety of cell types, including peripheral neurons and glia, craniofacial skeletal elements, pigment cells and portions of the cardiovascular system. Because of its contribution to multiple lineages, abnormal development of the NC can result in a wide array of clinical manifestations affecting multiple organ systems. Therefore, studies focusing on the molecular mechanisms regulating the emergence of the NC are critical to further our understanding of a broad range of human congenital malformations. Our laboratory is studying the regulatory inputs controlling NC development, using the frog Xenopus laevis as a model system. Using a combination of biochemical, molecular and embryological approaches our goals are to define: (i) the relative importance of Bmp, Wnt and Fgf signaling pathways in NC induction; (ii) the downstream targets of Pax3 and Zic1, two transcription factors activated early at the neural plate border and critically required for NC specification; and (iii) the unique functions of SoxE proteins in driving NC cells diversification. We are also actively studying the factors regulating the specification of the cranial placodes, precursors of the paired sense organs and cranial ganglia.
