9506899 Ho This proposal seeks to understand the development of posterior body formation in the relatively simple vertebrate system of zebrafish. By using cell marking and time lapse techniques, a fate map for tail bud development will be elucidated to test the hypothesis that cells within the tail bud contribute to the formation of the posterior body in an organized, stereotypic manner. The cell movements and final cell fates stemming from the tail bud region will be correlated with specific patterns of gene expression in the tail bud. This proposal also will determine if an organizer region exists for the proper development of the posterior body and will determine if this organizer region is related to the organizer region of the trunk and head regions. ***
