The neural crest is a population of multipotent precursor cells that contributes to various structures in vertebrates. During development, neural crest cells separate from the neural tube and migrate throughout the embryo, choosing between different fates. Neural crest cells from the spinal cord region give rise to melanocytes as well as the neurons and glial cells of the peripheral nervous system, while cranial crest from the hindbrain region differentiates into smooth muscle, craniofacial cartilage, and bone. Environmental cues are important in regulating the fate of neural crest cells, and it is generally thought that these cells are directed toward particular fates by signaling molecules. The exact nature of these signals, however, is not well known, but certain signaling molecules have been shown to be important in neural crest cell induction and differentiation, including Wnts and bone morphogenetic proteins (BMPs).
In an effort to further explore the role environmental cues play in neural crest cell fate determination, we are optimizing a technique for growing neural crest cells in vitro from dorsal explants of chick and quail embryos. Once this technique has been perfected such that neural crest cells form and survive but are not predisposed toward any specific fate, we will add to the cells in varying amounts different signaling molecules, as well as agents blocking these signals, and observe the effect upon cell differentiation. In this manner, we hope to better understand the process of neural crest cell fate determination and the roles that certain environmental cues play in this process. We hypothesize that signaling molecules present in the environment of the developing embryo are both necessary and sufficient for the induction and differentiation of neural crest cells into specific cell fates.