The Role of AP-1 in the Gonadotrope

AP-1 在促性腺激素中的作用

基本信息

批准号：
8452618
负责人：
DJURDJICA COSS
金额：
$ 27.68万
依托单位：
UNIVERSITY OF CALIFORNIA RIVERSIDE
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-04-01 至 2015-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8452618
关键词：
Address Affect Animals Anterior Pituitary Gland Binding Biological Assay Cell Culture Techniques DNA Binding Development Embryo FOS gene Female Fertility Follicle Stimulating Hormone Functional disorder Gametogenesis Gene Expression Gene Expression Regulation Genes Genetic Transcription Genetically Modified Animals Goals Gonadal structure Gonadotrope Cell Gonadotropin Hormone Releasing Hormone Gonadotropins Health Heterodimerization Hormones Hypothalamic structure Immediate-Early Genes JUN gene Knock-out Lead Luteinizing Hormone Mammals Mediating Modeling Molecular Mus Ovarian Follicle Phenotype Physiology Pituitary Gland Population Protein Isoforms Proteins Regulation Reproduction Reproductive History Reproductive system Role Steroid biosynthesis System Technology Transcription Factor AP-1 Translations Work chromatin immunoprecipitation fitness hormone regulation in utero in vivo insight novel strategies overexpression promoter protein degradation reproductive function transcription factor

项目摘要

DESCRIPTION (provided by applicant): Gametogenesis in females is controlled by follicle-stimulating hormone (FSH) from the pituitary, which is, in turn, regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. GnRH regulates FSH synthesis through induction of the immediate early gene, c-Fos, which, upon heterodimerization with c-Jun, creates an AP-1 transcription factor that binds the promoter of the FSH 2-subunit gene. The overall goal of this application is to ascertain the mechanism of GnRH induction of c-Fos and to elucidate the role of AP-1 in the gonadotrope in vivo. AP-1 is the only factor known to be involved in the induction of the FSH 2-subunit gene by GnRH. c-Fos, the most highly GnRH-induced gene in the gonadotrope, is the most regulated AP-1 isoform, while c-Jun expression varies less with hormone treatment. The molecular mechanism of c-Fos induction by GnRH in the gonadotrope cell is not known. Neither has a role for AP-1 in reproduction in vivo been determined. Herein, I will utilize novel approaches to delineate the mechanisms underlying the regulation of c- Fos expression by GnRH. In the first aim, I will determine the molecular mechanism of c-Fos induction by GnRH. In the second aim, I will determine the regulation of protein stability and degradation, since c-Fos is an immediate-early gene with a very unstable message and labile protein, and its cellular concentration is controlled on the level of turnover, as much as on the level of expression. In the third aim of this proposal, I will determine the function of AP-1 in reproduction in vivo with the use of genetically modified animals. First, I will assess reproductive function and gonadotropin expression in c-Fos deficient animals and then, as complementary approach, use mice that lack c-Jun specifically in the pituitary gonadotrope. Jun isoforms are obligatory heterodimeric partners for Fos isoforms, whose interaction creates an AP-1 transcription factor that binds DNA. c-Jun, in particular, is essential for development, since knock-out animals die in utero, and with the use of CRE-lox system, I will analyze the function of c-Jun in gonadotrope in vivo. Results obtained from these studies will make substantial contributions to our understanding of the molecular mechanisms that affect gene expression in the gonadotrope and provide insight into the physiology and pathophysiology of the mammalian reproductive system. I propose to expand our understanding of molecular mechanisms of GnRH induction of c- Fos gene in the gonadotrope in a cell culture model, which will lead to a better understanding of GnRH regulation of gene expression in the pituitary, and the function of AP-1 in vivo, utilizing genetically modified mice.

描述（由申请人提供）：女性的配子发生通过垂体中刺激卵泡激素（FSH）来控制，这反过来又受促性腺激素释放激素（GNRH）的调节。 GnRH通过诱导直接的早期基因C-FOS调节FSH合成，该基因与C-Jun异二聚化后，会产生一个AP-1转录因子，该AP-1转录因子结合FSH 2-Subunit基因的启动子。该应用的总体目标是确定C-FOS的GnRH诱导机理，并阐明AP-1在体内促性腺导体中的作用。 AP-1是唯一与GnRH诱导FSH 2亚基基因相关的因素。 C-FOS是促性腺瘤中GNRH诱导的基因最高的基因，是最调节的AP-1同工型，而C-JUN表达随激素处理而变化较小。 GNRH在促性腺细胞中诱导C-FOS的分子机制尚不清楚。确定AP-1在体内繁殖中都没有作用。在本文中，我将利用新颖的方法来描述GNRH调节C-FOS表达的基础机制。在第一个目标中，我将确定GnRH诱导C-FOS的分子机制。在第二个目标中，我将确定蛋白质稳定性和降解的调节，因为C-FOS是一个直接的早期基因，具有非常不稳定的信息和不稳定的蛋白质，并且其细胞浓度在离职水平上受到控制，以及在表达水平上。在该提案的第三个目的中，我将通过使用转基因动物来确定AP-1在体内繁殖中的功能。首先，我将评估C-FOS缺乏动物中的生殖功能和促性腺激素表达，然后作为互补方法，使用在垂体性促性腺促性腺促性腺中缺乏C-JUN的小鼠。 JUN同工型是FOS同工型的强制性异二聚体伙伴，其相互作用会产生结合DNA的AP-1转录因子。尤其是C-Jun对于发育至关重要，因为敲除动物在子宫内死亡，并且使用CRE-Lox系统，我将分析C-Jun在体内促性腺导体中的功能。从这些研究中获得的结果将对我们对影响促性腺导体基因表达的分子机制的理解做出重大贡献，并洞悉哺乳动物生殖系统的生理学和病理生理学。我建议我们扩展我们对细胞培养模型中促性腺素基因GnRH诱导GnRH诱导的分子机制的理解，这将使人们更好地理解垂体中基因表达的GnRH调节，并利用基因修饰的小鼠在体内的AP-1功能。