Regulation of insulins by the Rhox5 homeobox gene supports spermatogenesis

Rhox5 同源框基因对胰岛素的调节支持精子发生

基本信息

批准号：
7844172
负责人：
JAMES Arthur MACLEAN
金额：
$ 0.91万
依托单位：
SOUTHERN ILLINOIS UNIVERSITY CARBONDALE
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：
2009-06-01 至 2010-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7844172
关键词：
15p Accounting Androgens Apoptosis Binding Biological Biological Models Biological Process Breeding Cell Communication Cell Cycle Regulation Cell Death Cell Line Cell Maturation Cell Survival Complex Consult Data Defect Development Elements Embryo Epithelial Cells Event Exhibits Failure Fertility Gene Expression Gene Targeting Genes Genetic Transcription Germ Cells Gonadal structure Homeobox Homeobox Genes Hormonal Human IGF1 gene Insulin Insulin-Like Growth Factor Receptor Knockout Mice Knowledge Laboratories Link Luciferases Mediating Metabolic Metabolism Microarray Analysis Molecular Morphology Mus Nuclear Hormone Receptors Nurses Organ Pancreas Patients Peroxisome Proliferator-Activated Receptors Physiology Plasmids Principal Investigator Process Proteins Regulation Regulatory Pathway Reporter Reproduction Reproductive system Research Response Elements Role Scientist Seminal fluid Somatic Cell Sperm Count Procedure Sperm Motility Spermatogenesis Staging Supporting Cell System Techniques Testis Tissues Transcription factor genes Transcriptional Activation Transfection Work X Chromosome adiponectin asthenospermia base cell growth regulation cell type cofactor design in vivo insulin signaling knockout gene leydig interstitial cell male mind control postnatal programs promoter reproductive reproductive development research study resistin response sertoli cell spermatogenic epithelium structure stem transcription factor

项目摘要

Project Summary Homeobox genes encode transcription factors that control a wide variety of biological events. I recently identified a cluster of homeobox genes that are good candidates to regulate male reproductive development and physiology. Many of these reproductive homeobox on the X chromosome (Rhox) genes are androgen regulated and most are expressed in Sertoli cells (the nurse cells that support spermatogenesis), suggesting that they regulate the expression of somatic-cell gene products crucial for germ-cell development. Indeed, targeted deletion of one of these genes, Rhox5 (Pem), results in male subfertility, marked by increased germ-cell apoptosis and abnormal sperm motility. To begin to uncover the molecular events triggered by Rhox5 in Sertoli cells, I used microarray analysis to identify Rhox5-regulated genes, many of which encode proteins that have roles in metabolism, including insulin II (Ins2), resistin, and adiponectin, and the nuclear hormone receptor PPAR. Because insulin-like factors have recently been shown to support germ cell survival, I focused my initial studies on Rhox5 regulation of Ins2. Transient transfection of Rhox5 expression plasmids increased the activity of Ins2 promoter-driven luciferase reporter constructs. This was a breakthrough discovery for our laboratory, as no putative Rhox5-response elements had ever discovered. Rhox5-mediated activation of the Ins2 promoter was Sertoli-cell specific, as it occurred in Sertoli cell lines and Sertoli cells purified from day 12 testes, but not cell lines derived from other tissues. This suggests that a Sertoli-specific cofactor is required for Rhox5-mediated transcriptional activation. In this application, I propose to characterize the mechanism by which Rhox5 regulates target genes in the testes. The experiments are designed to identify cofactors that work with Rhox5 to achieve cell-type specific expression of Rhox5-regulated genes. Because Rhox5 positively regulates metabolic factors that support germ cell survival, elucidation of the transcription control mechanism that leads to subfertility in Rhox5-null mice provides a useful model system for understanding human subfertility. Untreatable subfertility caused by poor semen quality accounts for 75% of patients consulting for fertility problems Project Narrative Untreatable subfertility caused by poor semen quality accounts for 75% of patients consulting for fertility problems. This is due mainly to defects in sperm numbers (oligozoospermia) and sperm motility (asthenozoospermia). My proposed research strives to understand the mechanism by which the Rhox5 homeobox transcription factor controls the expression of genes that support male germ cell development. Mice which lack the Rhox5 gene exhibit abnormalities in sperm number, sperm motility, and breeding efficiency. Thus, the characterization of Rhox5-null mice may also be useful as a model system for understanding human fertility problems.

项目概要同源盒基因编码控制多种生物的转录因子事件。我最近发现了一组同源盒基因，它们是调节的良好候选基因男性生殖发育和生理学。许多这些生殖同源盒 X 染色体 (Rhox) 基因受雄激素调节，大部分在支持细胞中表达（支持精子发生的护士细胞），表明它们调节对生殖细胞发育至关重要的体细胞基因产物。确实有针对性的删掉一个这些基因中的 Rhox5 (Pem) 会导致男性生育力低下，其特点是生殖细胞增加细胞凋亡和精子活力异常。开始揭示由在支持细胞中的 Rhox5 中，我使用微阵列分析来识别 Rhox5 调节的基因，其中许多它编码在新陈代谢中发挥作用的蛋白质，包括胰岛素 II (Ins2)、抵抗素和脂联素和核激素受体 PPAR。因为胰岛素样因子最近被证明支持生殖细胞存活，我的初步研究集中在 Rhox5 Ins2 的调节。瞬时转染Rhox5表达质粒增加活性 Ins2 启动子驱动的荧光素酶报告基因构建体。这是一个突破性的发现我们的实验室尚未发现任何假定的 Rhox5 反应元件。 Rhox5介导的 Ins2启动子的激活是支持细胞特异性的，因为它发生在支持细胞系中并且从第 12 天的睾丸中纯化的支持细胞，但不是来自其他组织的细胞系。这表明 Rhox5 介导的转录需要 Sertoli 特异性辅因子激活。在此应用中，我建议描述 Rhox5 的机制调节睾丸中的靶基因。这些实验旨在识别辅助因子与Rhox5合作实现Rhox5调节基因的细胞类型特异性表达。因为 Rhox5 正向调节支持生殖细胞存活的代谢因子，阐明了导致 Rhox5 缺失小鼠生育力低下的转录控制机制提供了一种有用的方法了解人类生育力低下的模型系统。因贫困导致的无法治愈的不育症咨询生育问题的患者中有 75% 因精液质量问题 Project Narrative 75%的患者因精液质量差而导致无法治愈的不育症生育问题咨询。这主要是由于精子数量缺陷造成的（少精子症）和精子活力（弱精子症）。我提出的研究致力于了解 Rhox5 同源盒转录因子控制支持雄性生殖细胞发育的基因的表达。缺乏Rhox5基因的小鼠表现出精子数量、精子活力和繁殖效率的异常。因此， Rhox5 缺失小鼠的表征也可能有助于作为模型系统来理解人类的生育问题。

项目成果

期刊论文数量（1）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Rhox8 Ablation in the Sertoli Cells Using a Tissue-Specific RNAi Approach Results in Impaired Male Fertility in Mice.

使用组织特异性 RNAi 方法消除支持细胞中的 Rhox8 会导致小鼠雄性生育力受损。

DOI：
发表时间：
2015-07
期刊：
影响因子：
3.6
作者：
Welborn, Joshua P;Davis, Matthew G;Ebers, Steven D;Stodden, Genna R;Hayashi, Kanako;Cheatwood, Joseph L;Rao, Manjeet K;MacLean 2nd, James A
通讯作者：
MacLean 2nd, James A