Developmental neurobiology, molecular neurobiology studies of developing neuronal cell and synapses of the inner ear; neuronal regeneration in the inner ear; studies of Neurofibromatosis 1; stem cell studies of neuronal, Schwann cell and heart development This laboratory works on four different developmental problems. We are interested in the early development of neuronal lineages from the embryonic neural crest; which appears transiently during development and which is a source of peripheral nervous system neurons, among many other cell types. We use specific monoclonal antibodies and no-flow cytometry to isolate neural crest subpopulations. We also study the role of the neurofibromatosis I gene (a tumor suppressor gene) in neural crest development and neuronal/ melanocyte/Schwann cell lineage specification and apoptosis, using mouse embryonic stem cells. An additional line of research examines the role of the embryonic hindbrain, periotic mesenchyme and neural crest in shaping inner ear development and the roles of transcription factor and growth factor genes (e.g. BMPs) and their antagonists, such as Noggin, Chordin and DAN, in axis formation and development of the embryonic otocyst. We examine these issues in four model systems:, chick/quail; mouse/ immortalized inner ear cell lines from the Immortomouse and the zebrafish.