The proposed research, jointly supported by the Division of Cellular Biosciences and the Division of Chemistry, is the continuation of an interdisciplinary project to understand the action of juvenile hormone at the molecular level combining the disciplines of chemistry, molecular biology, and physiology. Major keys include understanding the molecular basis for hormonal regulation of gene expression in insects (L.M. Riddiford), biochemical and molecular studies of JH metabolism and synthesis (B.D. Hammock), and use of high specific activity labeled JHs and JHs (G.D. Prestwich). Three benefits result from this project. First, the scientific work is directed at a fundamental problem in regulation of gene expression, and the metamorphosis of insects in an easily accessible and fascinating model system for this study. Second, the practical implications of this work may lead to the development of new biologically specific and environmentally safer insect control strategies for crop pests. Third, the interdisciplinary training required for the students, postdoctoral fellow and faculty researchers involved enhances the quality and breadth of scientific inquiry in each laboratory.