HORMONAL REGULATION OF GENE EXPRESSION IN SERTOLI CELLS

FSH和雄激素作用于Sertoli细胞，调节其分泌 然而，在精子发生控制中起作用的蛋白质， 这些激素调节Sertoli基因表达的机制尚不清楚 为人所知。主要的分泌蛋白之一，雄激素的表达- 结合蛋白(ABP)，类似于精子发生的调节。在.期间 在两年的资助中，我们已经开发出了大鼠ABP基因作为模型 激素介导基因的分子机制研究系统 支持细胞的调节。我们的成就包括与世隔绝和 睾丸ABP基因和ABP基因的特性。此外，由于 我们共同努力克隆并鉴定了大鼠雄激素 受体(AR)基因，并产生特异性的AR抗体。带有ABP基因的cDNA 作为探索者，我们已经开始阐明ABP激素的机制 监管。 使用上面描述的开发工具，我们建议扩展这些 有三个特定目的的研究：1.定位ABP基因调控元件， 包括启动子、支持细胞特异性增强子元件和激素 利用CAT载体体外转染法研究调控元件 构建在原代Sertoli细胞和转基因动物上。2.划定 促卵泡刺激素和雄激素对ABP基因表达的影响体外研究 支持细胞培养将被用来确定这些激素是否有 对ABP基因表达的直接或间接影响。我们还将确定 其他激素、旁分泌和自分泌因子的调节作用。3. 帮助破译动脉粥样硬化蛋白在睾丸和睾丸中的功能(S)和作用方式 附睾症。这些研究包括ABP的细胞定位。 睾丸和附睾膜受体与类固醇的定位 体外诱变ABP的结合域。这些研究还包括 利用小鼠ABP基因的连锁分析寻找ABP突变体。 脑内ABP基因表达的研究可能为研究ABP提供新的视角 功能。 我们的研究将对支持细胞基因的认识有很大的帮助 支持细胞的主要分泌物--动脉粥样硬化蛋白的调节与功能(S) 蛋白。这种精子发生的维持，并将有助于 生育缺陷的识别和可能的治疗。

FSH and androgens act on Sertoli cells to regulate the secretion of proteins that function in the control of spermatogenesis, however, the mechanisms by which these hormones regulate Sertoli gene expression is not known. The expression of one of the major secretory proteins, androgen- binding protein (ABP), parallels the regulation of spermatogenesis. During the two years of funding we have developed the rat ABP gene as a model system to study the molecular mechanisms of hormone-mediated gene regulation of the Sertoli cell. Our accomplishments include isolation and characterization of testicular ABP cDNA and the ABP gene. Furthermore, as a collaborative effort we have cloned and characterized the rat androgen receptor (AR) cDNA and generated specific antibodies to AR. With ABP cDNA as probe we have begun elucidation of the mechanisms of ABP hormonal regulation. With the developed tools described above, we propose to extend these studies with three specific aims: 1. Locate ABP gene regulatory elements, including promoters, Sertoli cell specific enhancer elements and hormone regulatory elements, utilizing in vitro transfection of CAT vector constructs on primary Sertoli cells and transgenic animals. 2. Delineate the effects of FSH and androgen on ABP gene expression. In vitro studies with Sertoli cell cultures will be used to determine if these hormones have direct or indirect effects on ABP gene expression. We will also determine modulatory effects of other hormones, paracrine and autocrine factors. 3. Help decipher the function(s) and mode of action of ABP in the testis and epididymis. These studies include cellular localization of the ABP membrane receptor in testis and epididymis and mapping of the steroid- binding domain of ABP by in vitro mutagenesis. These studies also include a search for ABP mutants by linkage analysis of the mouse ABP gene. Studies of ABP gene expression in brain may provide new insights into ABP function. Our studies will contribute greatly to the knowledge of Sertoli cell gene regulation and the function(s) of ABP, a major Sertoli cell secretory protein. This maintenance of spermatogenesis, and will aid in the identification and possible treatment of fertility defects.