A new cell population regulating cell fate and morphogenesis in the mouse testis

调节小鼠睾丸细胞命运和形态发生的新细胞群

• 批准号: 7676351
• 负责人: Tony J. DeFalco
• 金额: $ 5.17万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7676351
• 关键词: Address; Adult; Androgens; Cell Adhesion; Cell Adhesion Molecules; Cell Communication; Cell Differentiation process; Cell Separation; Cells; Data; Development; Disease; Drosophila genus; Embryo; Exhibits; Extracellular Matrix; Extracellular Matrix Proteins; Family; Female; Fertility; Fetal Development; Fetus; Fluorescence-Activated Cell Sorting; Gene Family; Genes; Genetic Techniques; Germ Cells; Goals; Gonadal structure; Homologous Gene; Image; In Situ Hybridization; Infertility; Life; Mammals; Mediating; Methods; Molecular; Morphogenesis; Mus; Neurosecretory Systems; Organogenesis; Orthologous Gene; Pattern; Play; Population; Primordium; Process; Property; Regulation; Role; Seminiferous tubule structure; Shapes; Signal Transduction; Somatic Cell; Sorting - Cell Movement; Stem cells; Sterility; Structure; Testing; Testis; Transgenic Mice; Vascularization; base; cell fate specification; cell type; fetal; immunocytochemistry; in vivo; insight; interstitial; interstitial cell; leydig interstitial cell; male; member; mutant; notch protein; novel; progenitor; reproductive; sertoli cell; sex; sperm cell; trafficking; transcription factor

DESCRIPTION (provided by applicant): Our goal is to understand the mechanisms of cell fate specification and cellular reorganization that transform the fetal gonad into a functional testis. The first step of testis organogenesis is the commitment of approximately half of the somatic cells in the gonad primordium to the Sertoli cell fate. Sertoli cells surround germ cells and undergo the process of de novo cord formation. This basic process of cell sorting defines two compartments of the testis: the testis cords and the interstitium. The testis cords will become the seminiferous tubules, where sperm are produced in adult life, whereas the androgen-producing Leydig cells and other less well-characterized populations differentiate in the interstitium. Although the process of cord formation is essential for masculinization of the fetus and fertility of the adult, it is not well understood. It has been viewed as a Sertoli-cell-driven process; however, several lines of evidence suggest that interstitial cells play a critical role in shaping the process of testis cord formation. One gene that is essential for cell sorting during gonad morphogenesis in Drosophila is traffic jam (tj). tj encodes a member of the Maf transcription factor family, and promotes organogenesis of the Drosophila gonad via the regulation of cell adhesion molecules (CAMs). The mammalian ortholog of tj, MafB, is expressed in an uncharacterized population of progenitor cells that sort out from Sertoli cells at the beginning of fetal testis formation and give rise to the interstitium of the testis. MafB expression is closely associated with the vasculature, and later becomes restricted to fetal Leydig cells. We hypothesize that MafB plays a role in specification of the cell types of the interstitium and in the formation of testis cords, likely acting through control of CAMs or extracellular matrix (ECM) proteins. We have recently shown that Notch signaling is required for regulation of the progenitor population in the interstitium and for Leydig cell differentiation. In Specific Aim 1, we will investigate the hypothesis that Notch signaling is involved in the specification of MafB-expressing cells, using in vivo and ex vivo Notch gain- and Ibss-of-function analysis via immunocytochemistry, in situ hybridization, and quantitative PCR. In Specific Aim 2, we propose to elucidate the role of MafB-expressing cells during testis morphogenesis, employing PCR, microarray techniques, and genetic methods to determine which CAMs are regulated by MafB. In both aims, we will utilize several transgenic mouse lines for live imaging and fluorescence-activated cell sorting to study testis morphogenesis at the cellular level. This study of cell fate specification and cell-cell interactions will contribute to our basic understanding of organogenesis and provide insight into the developmental basis for infertility and reproductive disorders.

描述（由申请人提供）：我们的目标是了解细胞命运规范和细胞重组的机制，这些机制将胎儿性腺转化为功能性睾丸。睾丸器官发生的第一步是，性腺原始中大约一半的体细胞对Sertoli细胞命运的承诺。 Sertoli细胞围绕生殖细胞并经历从头形成的过程。细胞分类的基本过程定义了睾丸的两个隔室：睾丸绳和间质。睾丸绳将成为生精的小管，在成人生活中产生精子，而产生雄激素的Leydig细胞和其他特征较低的人群在间质中有区别。尽管绳索形成的过程对于成年人的胎儿和生育能力是必不可少的，但尚不清楚。它已被视为Sertoli-Cell驱动的过程。然而，几条证据表明，间质细胞在塑造睾丸绳形成过程中起关键作用。果蝇中性腺形态发生期间细胞分选的一种基因是交通拥堵（TJ）。 TJ编码MAF转录因子家族的成员，并通过调节细胞粘附分子（CAM）来促进果蝇性腺的器官发生。 TJ的MAFB的哺乳动物直系同源物在胎儿睾丸形成开始时从Sertoli细胞中排出的祖细胞的群体表达，并引起睾丸的间质。 MAFB表达与脉管系统密切相关，后来仅限于胎儿leydig细胞。我们假设MAFB在间质的细胞类型和睾丸绳的形成中起着作用，可能通过控制CAM或细胞外基质（ECM）蛋白的作用。我们最近表明，调节间质和leydig细胞分化的祖细胞种群需要缺口信号传导。在特定的目标1中，我们将研究一个假设，即使用体内和Ex Vivo Notch增益和IBSS的功能分析通过免疫细胞化学，原位杂交和定量PCR涉及表达MAFB细胞的规范。在特定目标2中，我们建议阐明在睾丸形态发生过程中表达MAFB细胞的作用，采用PCR，微阵列技术和遗传方法来确定哪些CAM受MAFB调节。在这两个目标中，我们都将利用几种转基因小鼠系进行实时成像和荧光激活的细胞分选，以研究细胞水平的睾丸形态发生。这项对细胞命运规范和细胞 - 细胞相互作用的研究将有助于我们对器官发生的基本理解，并洞悉不孕症和生殖疾病的发育基础。