HORMONAL CONTROL OF C-KINASE CORPUS LUTEUM FUNCTION

虽然黄体生成素（LH）在体内的许多作用 黄体被认为是由cAMP介导的， LH未知。 推测LH诱导的卵巢癌事件可能与LH诱导的卵巢癌细胞凋亡有关。 由cAMP介导的组织通过cAMP依赖性蛋白激酶发生。 蛋白质磷酸化是蛋白质翻译后修饰的主要途径之一。 调节细胞功能的机制。 我们最近 描述了卵巢组织中另一个重要的信使系统， 与蛋白质磷酸化有关。 受体介导的第二次增加 来源于磷酸肌醇代谢的信使（二酰基甘油和 肌醇磷酸盐）导致钙-和 磷脂依赖性蛋白激酶（C-激酶）。 调控 LH和其他激素的磷酸肌醇代谢以及 C-激酶在黄体中的表达提示C-激酶活性的控制 与黄体的功能有关。 该委员会的具体目标 拟议的研究是纯化和进一步表征这种新蛋白质 激酶及其生理意义 黄体 纯化酶的目的是： 确定C-激酶活性所需的特异性辅因子，2） 产生C-激酶的单克隆抗体用于检测 和C-激酶的定量，和3）确定底物特异性 C-激酶 C激酶的生理学作用将通过1） 确定酶活性在整个生命周期中是否变化 和2）确定酶活性是否受 LH或其他已知调节黄体功能的因素。 可能的 C-激酶参与调节黄体功能将是 通过检查其在1）促性腺激素结合，2）受体 磷酸化，3）腺苷酸环化酶活化，和4）孕酮 合成. 这些研究将通过监测 外源性和内源性底物蛋白的磷酸化。 的 对卵巢C-激酶的研究可能会提供新的见解， LH的作用机制，并建立一个链接， C-激酶活化和黄体功能的变化。

Although many of the effects of luteinizing hormone (LH) in the corpus luteum are thought to be mediated by cAMP, the exact mechanism of action of LH is unknown. It is presumed that the LH-induced events in ovarian tissues mediated by cAMP occur via cAMP-dependent protein kinases. Phosphorylation of proteins is one of the major post-translational mechanisms by which cellular functions are regulated. We have recently described another important messenger system in ovarian tissues which is linked to protein phosphorylation. Receptor-mediated increases in second messengers derived from phosphoinositide metabolism (diacylglycerol and inositol phosphates) lead to the activation of a calcium- and phospholipid-dependent protein kinase (C-kinase). The regulation of phosphoinositide metabolism by LH and other hormones and the presence of C-kinase in the corpus luteum suggest that the control of C-kinase activity is related to the function of the corpus luteum. The specific aims of the proposed research are to purify and further characterize this new protein kinase and evaluate its physiological significance in rat and bovine corpora lutea. The enzyme will be purified with the objectives of 1) determining the specific co-factors required for C-kinase activity, 2) producing monoclonal antibodies to C-kinase for the purpose of detection and quantitation of C-kinase, and 3) determining the substrate specificity of C-kinase. The physiological role for C-kinase will be examined by 1) determining whether or not enzyme activity varies throughout the life span of the corpus luteum and 2) determining if enzyme activity is regulated by LH or other factors known to regulate luteal function. The possible involvement of C-kinase in the regulation of luteal function will be determined by examining its role in 1) gonadotropin binding, 2) receptor phosphorylation, 3) adenylate cyclase activation, and 4) progesterone synthesis. These studies will be carried out by monitoring the phosphorylation of both exogenous and endogenous substrate proteins. The proposed studies on the ovarian C-kinase may provide new insight into the mechanism of LH action and establish a link between hormonally-induced changes in C-kinase activation and corpus luteum function.