Biochemical and pharmacological studies of human membrane progesterone receptors

描述（由申请人提供）：黄体酮是一种具有巨大生理重要性的类固醇激素。它不仅在生殖中起着核心作用，而且还具有神经活性。模仿或调节生物系统中黄体酮（孕激素和抗孕激素）作用的分子具有重要的药学意义，最常用于节育和治疗癌症和子宫内膜异位症。传统上，这些分子的生物活性是通过研究它们对核黄体酮受体的影响来测试的，它们对人体的影响也只是从这个角度来解释的。最近，一类新的黄体酮受体被发现存在于质膜上，这些受体很可能代表了黄体酮样分子的另一个体内靶点。因此，对这些膜孕酮受体的表征可能会更清楚地描绘出孕酮的生理学和类孕酮化合物的药理学。在这个建议中，将开发一个检测系统，用于研究这类新的黄体酮受体的生物化学和药理学。这将通过在一个叫做酿酒酵母的简单模型系统中表达人类黄体酮受体来实现。该系统的优点是能够功能性地表达这些受体，并且不具有其他黄体酮结合蛋白，这些黄体酮结合蛋白会干扰对单个人膜黄体酮受体的分析。该系统将首先用于探索这些新受体的结构方面与其结合孕酮和细胞内转导信号的能力之间的关系。这些膜孕激素受体感知细胞外孕激素并产生细胞内第二信使，负责细胞内的生理变化。然而，由这些受体产生的第二信使的身份是未知的。因此，本提案的第二个目标将包括识别信号转导的化学机制。最后，该系统可用于筛选大量具有药物、饮食和环境重要性的化合物，因为它们能够激活或抑制这类特定受体。这些实验将极大地扩展我们对黄体酮生物学以及黄体酮类药物的药理学和潜在副作用的理解。

DESCRIPTION (provided by applicant): Progesterone is a steroid hormone of tremendous physiological importance. Not only does it play a central role in reproduction, but it also has neuroactive properties. Molecules that mimic or modulate the effects of progesterone (progestins and antiprogestins) in biological systems are of significant pharmaceutical importance, being most commonly used for birth control and in the treatment of cancer and endometriosis. Traditionally, the biological activity of such molecules has been tested by investigating their effects on the well studied nuclear progesterone receptor and their effects in the human body have been interpreted solely in this light. Recently, a new class of receptors for progesterone has been discovered that reside on the plasma membrane and it is likely that these receptors represent an additional in vivo target for progesterone-like molecules. Consequently, the characterization of these membrane progesterone receptors is likely to paint a clearer picture of the physiology of progesterone and the pharmacology of progesterone-like compounds. In this proposal, an assay system will be developed with which the biochemistry and pharmacology of this new class of progesterone receptor can be investigated. This will be achieved by expressing the human progesterone receptors in a simple model system called Saccharomyces cerevisiae. This system has the benefit of being able to functionally express these receptors and of not possessing other progesterone binding proteins that can interfere with analysis of the individual human membrane progesterone receptors. This system will first be used to probe the relationship between the structural aspects of these new receptors and their ability to bind progesterone and transduce signals inside cells. These membrane progesterone receptors sense extracellular progesterone and produce an intracellular second messenger that is responsible for the physiological changes inside cells. However, the identity of the second messenger produced by these receptors is unknown. Therefore, the second goal of this proposal will consist of identifying the chemical mechanism of signal transduction. Finally, the system can be used to screen large numbers of chemical compounds of pharmaceutical, dietary and environmental importance for their ability to activate or inhibit receptors in this particular class. These experiments will significantly expand our understanding of the biology of progesterone as well as the pharmacology and potential side-effects of progesterone-like pharmaceuticals. PUBLIC HEALTH REVELANCE: The steroid hormone, progesterone, and molecules that modulate its effects are of critical pharmaceutical and environmental importance. We have established a system through which we can investigate how such molecules affect a new family of hormone receptors that is largely unstudied. The studies outlined in this proposal will significantly expand our understanding of how human cells sense and respond to steroid hormones.