Discussion of the proposal re-emphasized the strong points of the research plan. However, there was some concern that the proposed work may not have a particularly high impact. This factor somewhat moderated enthusiasm DESCRIPTION (adapted from the applicant's abstract): This application proposes experiments to examine how steroid hormone synthesis is controlled in different steroidogenic tissues. To accomplish this, the investigators will focus on the regulation of rat P450c17 in a series of steroidogenic cell lines. These studies will use in vitro transfection and gel shift assays. In Aim 1, the investigators will identify nuclear proteins from rodent Leydig tumor cell and adrenocortical cell lines that interact with regulatory elements in the rat P450c17 gene. In Specific Aim 2, they will clone these factors. In Specific Aim 3, the investigators will explore the role of SF-1 phosphorylation in mediating cAMP and/or basal P450c17 gene expression.