Long term objectives - To elucidate neuronal mechanisms of estrogen and glucocorticoid receptor (ER & GR) transcriptional regulation by combining molecular genetic and physiologic approaches. SPECIFIC AIMS 1- To investigate the molecular mechanisms which underlie an observed functional interaction between the ER & GR at the AP-1 cis element (IRE). Specific Aim 1 : To establish the ER/GR/IRE interaction. Specific Aim 2: To determine the effect of different Jun and Fos family members on the interaction by transfection studies. Specific Aim 3: To investigate molecular mechanisms of the interaction in mammalian cells and yeast. SPECIFIC AIMS 4&5: To analyze mechanisms of ER and GR transcriptional regulation through estrogen and glucocorticoid response elements (ERE & GRE) and the IRE in vitro and in vivo neuronal systems. Specific Aim 4: To analyze ER and GR transcriptional regulation at ERE, GRE, and IRE in a neuronal cell line. Specific Aim 5: To generate mice transgenic for ERE, GRE and TRE activated reporter transgenes. Accomplishing these specific aims will elucidate molecular mechanisms of the stress response and effects of stress on reproductive function. Specific Aims 1-3 will be accomplished by transfection studies in mammalian cells and transformation of yeast. Yeast will provide a highly efficient means for identifying protein surfaces required for the ER/GR/TRE interaction. Specific Aims 4&5 will be accomplished by constructing response element driven reporter transgenes, testing them in the GT1 neuronal cell line, and making transgenic mice. Steroid manipulations of mice will permit identification of neurons and neuronal networks which contain transcriptionally functional ER and GR.