This research is based upon the hypothesis that the expression of pigmentation patterns of vertebrates from primitive fishes to man is determined by the presence of intrinsic inhibiting and/or stimulating factors present in the skin. It is considered that these factors work in concert with other agents, viz. hormones such as melanocyte stimulating hormone (MSH), to either inhibit or stimulate the development and maintenance of the circumscribed pigment cells of vertebrates. These include the black or brown melanophores, the yellow to red xanthophores, and the iridescent iridophores. All three pigment cell types are derived from the cadre of the neural crest cells that migrate from atop the neural tube to the skin. Presumably, after these prospective pigment cells arrive at their destinations, they are exposed to the localized putative melanization inhibiting factors (MIF) and melanization stimulating factors (MSF) which affect pigment cell development. The activities of these factors, both individually and in combination, on various aspects of amphibian pigment cell expression will be tested in vivo and in vitro. Both biological and biochemical characterization of the putative MIF and MSF will be undertaken and antibodies raised to these molecule will be utilized as probes to further study the distribution and activities of these factors. This information should provide insight into our understanding of the mechanisms of pigment pattern formation and maintenance. These patterns include the dorsal ventral pigmentation patterns commonly found in most vertebrates as well as the individual spots and stripes that are also seen frequently.
