Role of Y chromosomal genes in male fertility

Y染色体基因在男性生育能力中的作用

• 批准号: 7842959
• 负责人: Alexander I Agoulnik
• 金额: $ 22.85万
• 依托单位: FLORIDA INTERNATIONAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-07 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7842959
• 关键词: Fertility; Genes; Role; male

DESCRIPTION (provided by applicant): The critical role of Y chromosome in sex determination and male fertility is one of the basic paradigms in reproductive biology. The most frequent cause of etiopathogenetic male infertility revealed by molecular genetic techniques is a deletion of the Y chromosome. The absence of genetic recombination of the Y chromosome makes it impossible to perform traditional positional mapping and cloning of the Y genes responsible for male germ cell progression. Deletion analysis of the human and mouse Y chromosome suggested several critical regions involved in male fertility. In mice most of the genes responsible for spermatogonial maintenance and germ cell differentiation are located on the short arm of the Y chromosome. One of such genes (Eif2s3y) was identified by transgenic gene rescue approach; however more recent data indicate that the additional genes within this deletion interval participate in spermatogenic progression. Further transgenic rescue experiments however become highly complicated as a production of mice with multiple transgenes on Y chromosome deletion background is required. Despite numerous attempts Y chromosome gene targeting using conventional ES cell technology did not result in live mouse mutant. We suggest here to target Y chromosome gene expression by production of mice with short hairpin RNA transgene. The activation of shRNA transgene expression and subsequent RNA interference in the proposed experiments is controlled by cre-recombinase, thus allowing transgene germ line transmission and specific gene targeting at different spermatogenic stages. This approach also allows targeting both single and multiple copy Y chromosomal genes, with a strict control of RNAi specificity. Our main hypothesis is that the genes located on the Y chromosome contribute to male germ cell maintenance and differentiation. The overall objective of current project is to characterize the spermatogenic functions of the Y chromosome genes through production and analysis of reproductive characteristics of shRNA transgenic males.To address this goal we designed two specific aims: 1. To produce conditional shRNA transgenic mice targeting eight genes from the short arm of the Y chromosome. 2. We will analyze the effect of Y chromosome gene suppression on spermatogenesis in males with shRNA transgene activated at different stages of male germ cell differentiation. Information obtained from these studies will serve as a basis for future studies in accurate genetic diagnostics of male infertility, the knowledge-based etiological therapy of symptoms associated with Y chromosome deletion, as well as contraceptive research. PUBLIC HEALTH RELEVANCE: The critical role of Y chromosome in sex determination and male fertility is one of the basic paradigms in reproductive biology. We propose to study the spermatogenesis and germ cell renewal in novel transgenic mice with targeted down-regulation of the Y chromosomal genes.

描述（由申请人提供）：Y染色体在性别决定和男性生育力中的关键作用是生殖生物学的基本范式之一。通过分子遗传学技术揭示的病因性男性不育的最常见原因是Y染色体的缺失。Y染色体的遗传重组的缺乏使得不可能对负责男性生殖细胞进展的Y基因进行传统的位置定位和克隆。人类和小鼠Y染色体的缺失分析表明，男性生育力涉及几个关键区域。在小鼠中，大多数负责精原细胞维持和生殖细胞分化的基因位于Y染色体的短臂上。其中一个基因（Eif 2s 3 y）是通过转基因拯救方法鉴定的;然而，最近的数据表明，该缺失区间内的其他基因参与精子发生进展。然而，进一步的转基因拯救实验变得非常复杂，因为需要产生在Y染色体缺失背景上具有多个转基因的小鼠。尽管多次尝试Y染色体基因靶向使用常规ES细胞技术没有导致活的小鼠突变体。我们在这里建议通过生产带有短发夹RNA转基因的小鼠来靶向Y染色体基因表达。在所提出的实验中，shRNA转基因表达的激活和随后的RNA干扰由cre重组酶控制，从而允许转基因生殖系传递和在不同生精阶段的特异性基因靶向。这种方法还允许靶向单拷贝和多拷贝Y染色体基因，并严格控制RNAi特异性。我们的主要假设是位于Y染色体上的基因有助于男性生殖细胞的维持和分化。本课题的总体目标是通过制备和分析shRNA转基因雄性小鼠的生殖特性来研究Y染色体基因的生精功能。目的：建立靶向Y染色体短臂8个基因的条件性shRNA转基因小鼠。2.我们将分析在男性生殖细胞分化的不同阶段激活的shRNA转基因对Y染色体基因抑制对男性精子发生的影响。从这些研究中获得的信息将作为未来研究的基础，用于男性不育症的准确遗传诊断，Y染色体缺失相关症状的基于知识的病因学治疗以及避孕研究。公共卫生关系：Y染色体在性别决定和雄性育性中的关键作用是生殖生物学的基本范式之一。我们建议在新的转基因小鼠中研究精子发生和生殖细胞更新与靶向下调Y染色体基因。