MEMBRANE EVENTS FOLLOWING HORMONE BINDING TO LH RECEPTOR

黄体和间质上的黄体激素受体 睾丸细胞结合黄体生成素和人绒毛膜 促性腺激素(HCG)调节类固醇的合成和分泌 腺体。我们的基本假设是荷尔蒙结合伴随着 黄体生成素受体与其他膜成分的相互作用 细胞骨架产生能够发出信号的激素受体复合体 转导。首先，我们将研究黄体生成素受体的相互作用 与细胞中的其他质膜蛋白一起激活 腺苷环化酶对激素结合的反应。我们将比较 与激素结合但不能结合的黄体生成素受体的分子动力学 利用功能性的黄体生成素受体复合体进行信号转导。 第二，我们将研究特定的膜蛋白与 配体结合后的黄体生成素受体，特别是那些可能是 只有当荷尔蒙-受体复合体的形成导致 激活腺苷酸环化酶。我们将使用生物物理方法 包括荧光能量转移技术来检测受体- 受体相互作用和光活化膜探针用于识别 受体附近的膜蛋白。第三，我们将确定如何 细胞骨架可能通过限制受体来限制黄体生成素的运动 在亚微米膜域内。我们将研究横向扩散 以及野生型和突变型黄体生成素受体在存在和 用光漂白恢复法检测细胞骨架的完整性 和单粒子跟踪技术。第四，我们将确定 磷脂酶C的激活是否依赖于组织 细胞膜上存在促黄体生成素受体的相互作用。我们会 比较稀疏表达的黄体生成素的分子运动和相互作用 磷脂酶C不被磷脂酶C激活的细胞中的受体 密集表达的黄体生成素受体能够激活cAMP和 磷脂酶C.科罗拉多州立大学有一种不同寻常的汇合 生殖生理学和仪器设备方面的专业知识 膜结构研究。这种情况为我们提供了一个独特的 有机会研究黄体生成素受体的组织和如何 组织调节受体的功能。

Luteinizing hormone (LH) receptors on the corpus luteum and on Leydig cells in the testis bind luteinizing hormone (LH) and human chorionic gonadotropin (hCG) to regulate steroid synthesis and secretion from these glands. Our basic hypothesis is that hormone binding is accompanied by interactions of the LH receptor with other membrane components and with the cytoskeleton to produce hormone-receptor complexes capable of signal transduction. First, we will examine the interactions of the LH receptor with other plasma membrane proteins in cells capable of activating adenylate cyclase in response to hormone binding. We will compare the molecular dynamics of the LH receptors that bind hormone but are unable to transduce signal with those of functional LH receptor complexes. Second, we will examine specific membrane proteins that interact with the LH receptor following ligand binding, particularly those which might be present only when formation of the hormone-receptor complex leads to activation of adenylate cyclase. We will use biophysical methods including fluorescence energy transfer techniques to examine receptor- receptor interactions and photoactivated membrane probes to identify membrane proteins near the receptor. Third, we will determine how the cytoskeleton restricts the movement of LH, possible by confining receptor within sub-micron membrane domains. We will examine the lateral diffusion and trajectories of wild-type and mutant LH receptors in the presence and absence of an intact cytoskeleton using photobleaching recovery methods and single particle tracking techniques. Fourth, we will determine whether activation of phospholipase C is dependent on the organization and interactions of LH receptors present on the cell membrane. We will compare the molecular motions and interactions of sparsely expressed LH receptors in cells where phospholipase C is not activated with those of densely expressed LH receptors capable of activating both cAMP and phospholipase C. Colorado State University has an unusual confluence of expertise in reproductive physiology and instrumental facilities for membrane structural studies. This situation provides us a unique opportunity to study both LH receptor organization and how this organization modulates receptor function.