Regulation of neural crest and cranial placodes formation
New York University
Department of Basic Science & Craniofacial Biology
NYU College of Denistry
345 East 24th Street
New York, NY
General/Lab Fax: (212) 995-4087
At the end of gastrulation, the ectoderm of the vertebrate embryo can be divided into three major domains: the non-neural ectoderm and the neural plate separated by a region known as the neural plate border. While the non-neural ectoderm and neural plate develop into epidermis and central nervous system, respectively, the neural plate border gives rise to the neural crest and the pre-placodal ectoderm. In the head region the neural crest contributes cartilages and bones to the face, and the pre-placodal ectoderm segregates into cranial sensory placodes that form the paired sense organs (nose, ear and lens). Both cell populations also contribute to the cephalic peripheral nervous system (cranial ganglia). Using Xenopus as a model system, our laboratory studies the cellular and molecular mechanisms controlling the development of the neural crest and cranial placodes.
Xenopus as a model system The frog Xenopus laevis is an extremely powerful system in which to investigate the molecular mechanisms underlying gene function. The large size of the Xenopus embryo and its development outside of the body of the female makes it an ideal system to alter gene function by microinjection of mRNA or antisense oligonucleotides. The first cleavage divides the Xenopus embryo along the left/right axis, therefore injection of one cell at the 2-cell stage can affect gene function in only one side of the embryo, while the other side serves as an internal control. Moreover the embryo has an extremely reproducible pattern of cleavage allowing for the manipulation of gene expression in restricted lineages of the developing embryo by injection at the 16 to 32-cell stage. The Xenopus animal cap/explant assay has also proven to be a remarkably versatile system to assess the ability of exogenously expressed transcription factors or signaling molecules to influence patterns of gene expression.