Estrogen Signaling and Estrogen Receptor Alpha Acetylation in the Pregnant Myometrium

项目摘要/摘要--项目2(克劳斯-派) 雌激素和孕激素信号通路在子宫肌层晚期的相互作用 孕期和足月期驱动着导致分娩的生理过程中的分子事件。 这些事件的缺陷或中断可能导致早产或延长分娩时间。上升的雌激素 妊娠晚期的水平使子宫肌层为导致分娩的事件做好准备(例如，增加 子宫肌层收缩能力)。然而，雌激素在子宫肌层近期作用的分子细节， 包括它对抗孕激素维持子宫肌层静止的机制， 都不清楚。雌激素(如雌二醇、雌二醇)和孕激素(如孕酮、P4)通过类固醇起作用。 受体蛋白(雌激素受体，ER；孕激素受体，PR)，其功能是配体调节的DNA 结合转录因子。ERα的活性是通过位点特异性的共价翻译后调控的 修饰，包括赖氨酸第266和第268位的乙酰化(在人的ERα中)，这增加了DNA... ERα的结合和转录活性。 我们建议进行的研究的长远目标，是加深对主要范畴的了解。 雌激素信号在近足月和分娩期间子宫肌层中的作用，即：(1)E2信号的作用 通过ERα，(2)E2-ERα拮抗P4-的孕激素作用的分子机制 基因组水平的孕激素受体(PR)；(3)ERα的分子机制 乙酰化调控子宫肌层中ERα依赖的基因调控。我们的假设是：(1) 雌激素在子宫肌层中的生理作用由基因组结合部位决定 (2)ERα结合位点(增强子)调控的靶基因；(2)ERα结合位点(增强子)调控的靶基因 通过ERα增加的雌激素信号在短期内拮抗P4的作用，部分是通过改变PR Cystrome，以及(3)乙酰化调节ERαCystrome(如形成、模式、特异性、稳定性)、ERα 增强子组装，以及靶基因的表达。 在这个提案中，我们概述了三个目标的一系列实验，使用了一个综合的方法和一个 生物化学、分子生物学、基因组学、小鼠遗传学和生理学的配套工具 这将检验我们的假设。总的来说，我们的研究将通过以下方式揭示分子机制的新方面 它连接的ERα控制着孕期和足月子宫肌层的生物学。

Project Summary/Abstract - Project 2 (Kraus - PI) Interplay between the estrogen and progestin signaling pathways in the uterine myometrium during late gestation and at term drive the molecular events underlying the physiological processes leading to parturition. Defects in, or disruption of, these events can cause premature delivery or prolonged labor. Rising estrogen levels in late gestation act to prepare the myometrium for the events leading to parturition (e.g., increased myometrial contractility). However, the molecular details of estrogen action in the myometrium near term, including the mechanisms by which it antagonizes the maintenance of myometrial quiescence by progestins, are unclear. Estrogens (e.g., estradiol, E2) and progestins (e.g., progesterone, P4) act through steroid receptor proteins (estrogen receptors, ERs; progestin receptors, PR), which function as ligand-regulated DNA binding transcription factors. The activity of ERα is modulated through site-specific covalent post-translational modifications, including acetylation at lysines 266 and 268 (in human ERα), which increases both the DNA- binding and transcriptional activities of ERα. The long-term objectives of our proposed studies are to achieve a better understanding of key aspects of estrogen signaling in the myometrium near term and during parturition, namely: (1) the role of E2 signaling through ERα, (2) the molecular mechanisms by which E2-ERα antagonizes the progestational actions of P4- progestin receptor (PR) at the level of the genome, and (3) the molecular mechanisms by which ERα acetylation controls ERα-dependent gene regulation in the myometrium. Our hypotheses are that (1) the physiological actions of estrogens in the myometrium are determined by the repertoire of genomic binding sites (i.e., “cistrome”) for ERα, as well as the target genes regulated by those ERα binding sites (enhancers), (2) increased estrogen signaling through ERα near term antagonizes P4 actions, in part, by altering the PR cistrome, and (3) acetylation regulates the ERα cistrome (e.g., formation, pattern, specificity, stability), ERα enhancer assembly, and the expression of target genes. In this proposal, we outline a series of experiments in three aims using an integrated approach with a complementary set of tools from biochemistry, molecular biology, genomics, mouse genetics, and physiology that will test our hypotheses. Collectively, our studies will reveal new aspects of the molecular mechanisms by which liganded ERα controls the biology of the myometrium during pregnancy and at term.