GnRH-Regulated Transcriptome in the Gonadotrope

促性腺激素中 GnRH 调节的转录组

• 批准号: 7645442
• 负责人: DJURDJICA COSS
• 金额: $ 23.18万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-13 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7645442
• 关键词: Binding; Binding Sites; Biological Assay; Cell Line; Cells; Complement; Complex; DNA; Data Set; Development; Elements; Enzymes; Equilibrium; FOS gene; Fertility; Follicle Stimulating Hormone; Functional disorder; Funding; Future; Gametogenesis; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Gene Targeting; Genes; Genetic Transcription; Glycoproteins; Goals; Gonadotrope Cell; Gonadotropin Hormone Releasing Hormone; Gonadotropins; Hormonal; Hormones; Hypothalamic structure; Immediate-Early Genes; JUN gene; Lead; Luteinizing Hormone; Mammals; Manuscripts; Methods; Molecular; Overlapping Genes; Physiology; Pituitary Gland; Play; Population; Regulation; Regulatory Element; Reproduction; Reproductive system; Research Personnel; Role; Secretory Component; Signal Pathway; Signal Transduction; Specificity; Steroid biosynthesis; Stimulus; Study models; Transcription Factor AP-1; Transcriptional Regulation; base; cDNA Library; chromatin remodeling; cofactor; glycosylation; gonad function; insight; interest; promoter; protein protein interaction; public health relevance; sex; tool; transcription factor; yeast two hybrid system

DESCRIPTION (provided by applicant): Regulation of gene transcription in the gonadotrope is a key regulatory step that determines the levels of gonadotropin hormones and therefore, regulates gonadal function. Gametogenesis and steroidogenesis in both sexes are controlled by these two hormones, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary, which are, in turn, regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. GnRH regulates gonadotropin synthesis through induction of the three immediate early genes: ATF3 induces the ? glycoprotein subunit, Egr-1 induces the LH? subunit, and AP-1 induces the FSH? subunit. The overall goal of this application is to determine the GnRH-regulated transcriptomes comprised of these immediate early genes in the gonadotrope cell. We propose two complimentary aims to dissect transcriptional regulation from a more comprehensive standpoint. In the first aim, we will determine the complement of direct target genes, in addition to gonadotropin subunits, of these immediate early genes by ChIP-chip, which will allow us to delineate the transcriptional regulatory network. The intersection of genes that are induced by GnRH, already identified by expression array analysis, and the direct gene targets of these three most highly induced transcription factors determined herein by ChIP-chip, will focus our analysis on the most functional binding elements. Furthermore, overlap of these data sets will identify the genes whose transcription may be regulated similarly to gonadotropins. In the second aim, using a two-hybrid screen of a cDNA library from gonadotrope-derived cells, we will identify molecules that interact with ATF3, Egr-1 or AP-1, with a special emphasis on coactivators and corepressors. These cofactors may contribute to differential expression of the three gonadotropin subunits. Additionally, we will determine whether selected target genes from the first aim have similar sets of binding sites in their promoters and/or require the same cofactors, which may contribute to regulation of their expression. This approach will help us triangulate, from a broad perspective, the differential regulation of the gonadotropin subunits and whether it is accomplished by formation of diverse complexes on their respective promoters, in addition to analyzing the more global regulation of gene transcription in the gonadotrope. The results from this proposal will also open new avenues to study chromatin remodeling and activation of basal transcriptional machinery. PUBLIC HEALTH RELEVANCE: Fertility in mammals is regulated by integration of different hormonal signals, which occurs at the level of the gonadotrope cell population in the pituitary gland. The integration ultimately results in the precisely orchestrated modulation of gene expression in the gonadotrope cell that leads to delicate balance of hormones that control reproduction. Thus, understanding the molecular mechanisms governing gonadotrope gene expression will lead to insight into the physiology and pathophysiology of the reproductive system.

描述（由申请人提供）：促性腺激素中基因转录的调节是决定促性腺激素水平并因此调节性腺功能的关键调节步骤。两性的配子发生和类固醇生成均由垂体中的卵泡刺激素 (FSH) 和黄体生成素 (LH) 这两种激素控制，而这两种激素又受到下丘脑中的促性腺激素释放激素 (GnRH) 的调节。 GnRH 通过诱导三个立即早期基因来调节促性腺激素合成： ATF3 诱导 ?糖蛋白亚基 Egr-1 诱导 LH？亚基，AP-1 诱导 FSH？亚基。本申请的总体目标是确定促性腺激素细胞中由这些立即早期基因组成的 GnRH 调节转录组。我们提出了两个互补的目标，从更全面的角度剖析转录调控。第一个目标是，除了促性腺激素亚基之外，我们将通过 ChIP 芯片确定这些立即早期基因的直接靶基因的补充，这将使我们能够描绘转录调控网络。已通过表达阵列分析鉴定出的 GnRH 诱导基因的交叉点，以及本文通过 ChIP 芯片确定的这三种诱导程度最高的转录因子的直接基因靶标，将使我们的分析集中在最具功能性的结合元件上。此外，这些数据集的重叠将识别其转录可能受到与促性腺激素类似的调节的基因。在第二个目标中，使用促性腺激素衍生细胞的 cDNA 文库的双杂交筛选，我们将鉴定与 ATF3、Egr-1 或 AP-1 相互作用的分子，特别强调共激活剂和辅阻遏物。这些辅助因子可能有助于三个促性腺激素亚基的差异表达。此外，我们将确定第一个目标中选定的靶基因在其启动子中是否具有相似的结合位点组和/或需要相同的辅因子，这可能有助于调节其表达。除了分析促性腺激素中基因转录的更全面的调控之外，这种方法将帮助我们从更广泛的角度对促性腺激素亚基的差异调节进行三角测量，以及它是否是通过在各自的启动子上形成不同的复合物来实现的。该提案的结果也将为研究染色质重塑和基础转录机制的激活开辟新途径。公共健康相关性：哺乳动物的生育能力是通过不同激素信号的整合来调节的，这种信号发生在垂体中促性腺激素细胞群的水平上。这种整合最终导致促性腺细胞中基因表达的精确协调调节，从而导致控制生殖的激素的微妙平衡。因此，了解控制促性腺激素基因表达的分子机制将有助于深入了解生殖系统的生理学和病理生理学。