REGULATION OF SF 1 EXPRESSION IN THE GONADS

甾体生成因子1 (SF-1)，或Ad4bp，是核激素受体家族的一员，对正常发育和类固醇激素的产生很重要。转录因子调节多种对内分泌系统重要的基因，对肾上腺和性腺的形成至关重要。表达和基因靶向研究表明，SF-1在肾上腺和性腺形成早期起作用，以两性二态方式调节，并且对出生后这些组织的功能很重要。这种转录因子的关键性质揭示了研究其调控和功能的重要机制的必要性。本提案的主要目标是鉴定和表征性腺中调节SF-1的转录因子。这将最终导致发现对性腺发育和功能、适当的内分泌调节以及增强我们对控制生育因素的理解至关重要的新蛋白质。通过瞬时转染分析（aim I）和转基因小鼠研究（aim III），我们将揭示SF- 1正确时空表达所需的所有元素。蛋白质/DNA的相互作用将使用电泳迁移转移测定和体内足迹来检查，从而鉴定和克隆重要的蛋白质。此外，我们提出（目的II）研究两种蛋白，USF1和USF2，我们已经发现它们与睾丸中重要的SF-1启动子元件（E-box）相互作用，因此涉及其调控。免疫组织化学和原位杂交分析将用于检测这些蛋白的表达，而共转染研究将研究这些转录因子对SF-1启动子的直接调节。

Steroidogenic factor 1 (SF-1), or Ad4bp, is a member of the nuclear hormone receptor family that is important for normal development and steroid hormone production. The transcription factor regulates a variety of genes important to the endocrine system and is essential for formation of adrenal glands and gonads. Expression and gene targeting studies indicated that SF-1 acts early in adrenal and gonad formation, is regulated in a sexually dimorphic manner, and is important for the function of these tissues after birth. The critical nature of this transcription factor reveals the need to examine mechanisms important to its regulation and function. The major goal of this proposal is to identify and characterize transcription factors regulating SF-1 in the gonads. This will ultimately lead to the discovery of new proteins important for gonadal development and function, proper endocrine regulation, and the enhancement of our understanding of factors controlling fertility. Using transient transfection analysis (aim I) and transgenic mouse studies (aim III), we will uncover all the needed elements for correct spatial and temporal expression of SF- 1. Protein/DNA interactions will be examined using electrophoretic mobility shift assays and in vivo footprinting, leading to identification and cloning of important proteins. In addition, studies are proposed (aim II) to investigate two proteins, USF1 and USF2, that we have shown interact with an important SF-1 promoter element (E-box) in the testis, and thus are implicated in its regulation. Immunohistochemistry and in situ hybridization analysis will be used to examine the expression of these proteins, while co-transfection studies will investigate the direct regulation of the SF-1 promoter by these transcription factors.