Biochemical and pharmacological studies of human membrane progesterone receptors

描述（由申请人提供）：Progesterone是一种具有巨大生理重要性的类固醇激素。它不仅在生殖中发挥核心作用，而且还具有神经活性。在生物系统中模拟或调节孕酮（孕激素和抗孕激素）作用的分子具有重要的药学重要性，最常用于节育和治疗癌症和子宫内膜异位症。传统上，这些分子的生物学活性已经通过研究它们对充分研究的核孕酮受体的作用来测试，并且它们在人体中的作用已经仅仅从这个角度来解释。最近，已经发现了一类新的孕酮受体，其位于质膜上，并且这些受体可能代表了孕酮样分子的另外的体内靶点。因此，这些膜孕酮受体的表征可能描绘出孕酮的生理学和孕酮样化合物的药理学的更清晰的画面。在这个建议中，将开发一个测定系统，可以研究这类新的孕酮受体的生物化学和药理学。这将通过在称为酿酒酵母的简单模型系统中表达人孕酮受体来实现。该系统具有能够功能性地表达这些受体并且不具有能够干扰个体人膜孕酮受体的分析的其它孕酮结合蛋白的益处。该系统将首先用于探测这些新受体的结构方面与其结合细胞内孕酮和孕酮信号的能力之间的关系。这些膜孕酮受体感知细胞外孕酮并产生细胞内第二信使，其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，以确定其激活或抑制这一特定类别受体的能力。这些实验将大大扩展我们对孕酮生物学以及孕酮类药物的药理学和潜在副作用的理解。 公共卫生部门：类固醇激素、孕酮和调节其作用的分子具有关键的药物和环境重要性。我们已经建立了一个系统，通过这个系统我们可以研究这些分子如何影响一个新的激素受体家族，这个家族在很大程度上还没有研究过。该提案中概述的研究将大大扩展我们对人类细胞如何感知和响应类固醇激素的理解。

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.