PROGESTERONE RECEPTOR GENE REGULATION IN THE RAT OVARY

本提案的长期目标是了解如何 孕激素调节女性生殖轴，特别是 卵巢孕激素受体(PR)基因调控的研究进展 颗粒细胞。孕激素被认为可以影响许多方面。 卵巢功能与参与正常排卵过程 和/或卵泡的黄体化。我们假设一个 细胞内PR分子可能介导孕酮在卵巢中的作用 并由此分离出大鼠PR的cDNA和基因组克隆以发起 多角度研究卵巢细胞的表达和调控 Prs.我们的初步结果显示PR基因的瞬时表达 围排卵期排卵前卵泡颗粒细胞的变化 这一时期强烈表明哺乳动物的PR可能参与其中。 排卵。乳腺癌PR基因表达的调控机制 细胞似乎与其他孕激素反应细胞有很大的不同。 细胞，因为促性腺激素，而不是雌激素，直接诱导PR基因 在大鼠颗粒细胞中的表达。促性腺激素诱导的PR基因 卵巢颗粒细胞的表达可能是由cAMP介导的。 介导的途径，至少部分，在转录水平上。我们的 初步结果还表明，蛋白激酶可能参与了 C参与卵巢颗粒细胞PR基因的调控。 因此，这个提议的中心假设是，PR基因在 卵巢颗粒细胞主要受G蛋白偶联调控 信号通路，例如依赖cAMP和DAG的通路。我们现在 建议扩展我们的初步研究，以研究细胞和 大鼠卵巢中PR基因调控的分子机制 颗粒细胞。这项提案的第一个目标是审查 直接参与PR基因的细胞内信号转导途径 在卵巢颗粒细胞中的表达；-我们的研究将集中在 这项提议的第二个目标是确定 并对介导激活的顺式DNA调控元件进行了表征 这些细胞内信号通路对PR基因的影响；我们的研究 将专注于cAMP或TPA诱导的PR基因的表达。决赛 这项建议的目标是研究雌激素在PR中的潜在作用 基因在大鼠颗粒细胞中的表达；我们将确定 卵巢颗粒细胞在调节雌激素诱导信号中的作用。我们 期待这些实验能增进我们对公关调控的理解 以及在排卵和/或黄体化过程中的作用 并提供一种框架，用于确定 PR功能的改变可能参与生殖疾病或 功能障碍。

The long-term objective of the present proposal is to understand how progestins regulate the female reproductive axis, with particular emphasis on progesterone receptor (PR) gene regulation in ovarian granulosa cells. Progestins have been proposed to affect many aspects of ovarian function and to participate in the normal process of ovulation and/or luteinization of the follicle. We hypothesized that an intracellular PR molecule may mediate progesterone action in the ovary and therefore, isolated the rat PR cDNA and genomic clones to initiate a multifaceted approach to study the expression and regulation of ovarian PRs. Our preliminary results demonstrating transient PR gene expression in the granulosa cells of preovulatory follicles during the periovulatory period strongly suggest the potential involvement of PRs for mammalian ovulation. The regulatory mechanisms for PR gene expression in these cells appear to be quite different from other progesterone-responsive cells, because gonadotropins, but not estrogen, directly induce PR gene expression in rat granulosa cells. This gonadotropin-induced PR gene expression in ovarian granulosa cells is likely to be mediated by a cAMP- mediated pathway, at least in part, at the level of transcription. Our preliminary results also suggest the likely involvement of protein kinase C in PR gene regulation in ovarian granulosa cells. The central hypothesis in this proposal, then, is that the PR gene in ovarian granulosa cells is regulated predominantly by G protein-coupled signaling pathways, for example cAMP- and DAG-dependent pathways. We now propose to extend our preliminary studies to investigate the cellular and molecular mechanisms by which the PR gene is regulated in rat ovarian granulosa cells. The first goal of this proposal is to examine intracellular signaling pathways which are directly involved in PR gene expression in ovarian granulosa cells; - our studies will focus on protein kinases A and C. The second goal of this proposal is to identify and characterize the cis-DNA regulatory elements mediating the activation of the PR gene by these intracellular signaling pathways; our studies will focus on cAMP- or TPA-induced expression of the PR gene. The final goal of this proposal is to examine the potential role of estrogen in PR gene expression in rat granulosa cells; we will determine the capacity of ovarian granulosa cells in mediating estrogen-induced signals. We expect these experiments to enhance our understanding of PR regulation and function for the process of ovulation and/or luteinization in the mammalian ovary and to provide a framework for determining whether alterations in PR function might participate in reproductive diseases or dysfunction.