Combinatorial Signals & Gene Expression in Trophoblasts

组合信号

• 批准号: 6621206
• 负责人: MARK S ROBERSON
• 金额: $ 28.2万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-20 至 2007-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6621206
• 关键词: binding sites; biological signal transduction; cAMP response element binding protein; cell differentiation; chorionic gonadotropin; chromatin; developmental genetics; epidermal growth factor; gene expression; genetic regulation; genetic regulatory element; genetic transcription; genetically modified animals; growth factor receptors; homeobox genes; hormone biosynthesis; hormone regulation /control mechanism; human tissue; immunocytochemistry; laboratory mouse; placenta; tissue /cell culture; trophoblast

DESCRIPTION (provided by applicant): Chorionic gonadotropin (CG) is a key luteotropic hormone secreted by the developing conceptus in primates. Endocrine mechanisms contributing to maximal CG subunit synthesis are important determinants of a successful pregnancy. Preliminary evidence suggests that the CG alpha subunit gene is synergistically induced in a placental-specific manner via a complex transcriptional "unit" comprised of several cis elements (two CREs and the JRE) necessary for integration of multiple intracellular signals. The CRE binding complex consists of several activator (CREB, AP-1, CBP) and corepressor molecules (HDAC2). The JRE is a homeobox-binding site that interacts with Distal-less 3 (D1x3). This proposal details a complex series of experiments examining the hypothesis that transcriptional activators and repressors contribute combinatorially to the cell-specific regulation of the alpha subunit gene. Further, trophoblast differentiation depends upon gene programs induced by Dlx3. The overall goal is a comprehensive understanding of mechanisms governing CG synthesis and analysis of factors regulating trophoblast differentiation. The aims are: Aim 1: Continued analysis of the mechanisms that govern CRE-dependent alpha subunit gene regulation in trophoblasts. CRE-dependent alpha subunit gene regulation and the effects of the EGF and cAMP will be examined in primary human trophoblasts. Biochemical and mutagenesis studies investigate the role of coregulators within the CRE binding complex and defines the extent of chromatin remodeling within the alpha subunit promoter. Aim 2: Explore the role of Dlx3 in the regulation of the alpha subunit gene. Studies will analyze the Dlx3 expression pattern in primate placenta and during trophoblast differentiation in vitro by immunocytochemistry. Biochemical and mutagenesis studies will examine interactions between CRE and JRE binding complexes within the alpha subunit promoter. Interacting partners of Dlx3 that contribute to alpha subunit gene regulation and to trophoblast differentiation will be identified. Aim 3: Examine the role of Dlx3 in placental development and differentiation. The Dlx3 knockout mouse will be used to identify gene programs induced by Dlx3 in murine trophoblasts using state-of-the-art gene profiling analysis. To complement these studies, an investigation of the factors required to mediate transcriptional activation of the Dlx3 gene promoter that will lead to identification of "upstream" effectors of trophoblast differentiation will be conducted.

描述（由申请人提供）：绒毛膜促性腺激素（CG）是关键 灵长类动物发育中的孕体分泌的促黄体激素。内分泌 有助于最大 CG 亚基合成的机制很重要 成功怀孕的决定因素。初步证据表明 CG α亚基基因以胎盘特异性方式协同诱导 通过由几个顺式元件（两个 CRE 和 JRE）是整合多个细胞内信号所必需的。 CRE 结合复合物由多种激活剂（CREB、AP-1、CBP）和 辅抑制分子（HDAC2）。 JRE 是一个同源盒结合位点 与 Distal-less 3 (D1x3) 相互作用。该提案详细介绍了一系列复杂的 实验检验了转录激活因子和 阻遏物组合有助于细胞特异性调节 α亚基基因。此外，滋养层分化取决于基因 Dlx3 诱导的程序。总体目标是全面了解 CG合成的调控机制及调控因素分析 滋养层分化。目标是： 目标 1：继续分析 控制 CRE 依赖性 α 亚基基因调控的机制 滋养层细胞。 CRE 依赖性 α 亚基基因调控及其影响 将在原代人滋养层中检查 EGF 和 cAMP。生化 和诱变研究调查了 CRE 中核心调节因子的作用 结合复合物并定义 α 内染色质重塑的程度 亚基启动子。目标2：探索Dlx3在调节中的作用 α亚基基因。研究将分析灵长类动物中的 Dlx3 表达模式 胎盘和滋养层体外分化期间 免疫细胞化学。生化和诱变研究将检查 α 亚基内 CRE 和 JRE 结合复合物之间的相互作用 发起人。有助于 α 亚基基因的 Dlx3 相互作用伙伴 将鉴定调节和滋养层分化。目标 3： 检查 Dlx3 在胎盘发育和分化中的作用。 DLX3 敲除小鼠将用于鉴定 Dlx3 在小鼠中诱导的基因程序 使用最先进的基因分析分析滋养层细胞。来补充 这些研究调查了调解所需的因素 Dlx3 基因启动子的转录激活将导致 滋养层分化“上游”效应子的鉴定将是 实施。