Biochemical and pharmacological studies of human membrane progesterone receptors

描述(申请人提供)：黄体酮是一种具有极大生理重要性的类固醇激素。它不仅在生殖过程中起着核心作用，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意义，最常用于节育、癌症和子宫内膜异位症的治疗。传统上，这类分子的生物活性是通过研究它们对已被充分研究的核孕酮受体的影响来测试的，它们在人体内的影响仅从这个角度进行解释。最近，一类新的孕激素受体被发现存在于细胞膜上，这些受体很可能代表着体内孕酮类分子的另一个靶点。因此，对这些膜孕酮受体的表征可能会更清楚地描绘孕酮的生理和孕酮类化合物的药理。在这项建议中，将开发一种检测系统，用于研究这种新的孕激素受体的生化和药理作用。这将通过在一个名为酿酒酵母的简单模型系统中表达人孕酮受体来实现。这个系统的好处是能够功能性地表达这些受体，并且不具有其他可能干扰单个人膜孕酮受体分析的黄体酮结合蛋白。该系统将首先被用来探测这些新受体的结构方面与它们结合孕激素和在细胞内传递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，负责细胞内的生理变化。然而，这些受体产生的第二个信使的身份尚不清楚。因此，这项提议的第二个目标将包括确定信号转导的化学机制。最后，该系统可以用来筛选大量对药物、饮食和环境具有重要意义的化合物，因为它们有能力激活或抑制这一特定类别的受体。这些实验将极大地扩大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。 公共卫生研究：类固醇激素、黄体酮和调节其作用的分子在制药和环境方面都具有重要意义。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，而这个家族在很大程度上还没有被研究过。这项提案中概述的研究将极大地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.