Regulation of chromatin remodeling during spermiogenesis

精子发生过程中染色质重塑的调节

基本信息

批准号：
8815702
负责人：
PRABHAKARA P REDDI
金额：
$ 7.86万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-12-01 至 2015-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8815702
关键词：
Accounting Acrosome Adult Affect Applications Grants Archives Assisted Reproductive Technology Binding Biological Models Birth Breeding Bypass CCCTC-binding factor Cell Nucleus Cells ChIP-seq Chromatin Complex Conceptions Congenital Abnormality Couples DNA-Binding Proteins Defect Developed Countries Development Disease Embryonic Development Epigenetic Process European Event Feasibility Studies Fertility Fertilization Fetal Growth Retardation Flagella Genes Genetic Genetic Transcription Genome Germ Cells Germ Lines Histones Human Immunohistochemistry Infertility Injection of therapeutic agent Intercistronic Region Knock-out Knockout Mice Lead Life Male Infertility Malignant Childhood Neoplasm Methods Modeling Molecular Mus Mutant Strains Mice Natural Selections Nuclear Nuclear Proteins Phase Physical condensation Physical shape Pilot Projects Play Preparation Process Protamines Proteins Regulation Reproductive Health Risk Role Sperm Maturation Spermatids Spermatogenesis Spermiogenesis Spontaneous abortion Staging Technology Testing Testis Time Treatment Factor United States Ursidae Family Validation Work Zinc Fingers age group base chromatin remodeling egg embryonic stem cell gene repression genome-wide imprint improved insight knockout gene male mouse model novel promoter public health relevance reproductive research study screening sperm cell technology development transcription factor

项目摘要

DESCRIPTION (provided by applicant): The differentiation of round spermatids into spermatozoa, known as spermiogenesis, is a complex process involving the formation of the acrosome, the flagellum, and condensation of the nucleus. In preparation for condensation, the spermatid nucleus undergoes dramatic chromatin remodeling including genome-wide cessation of transcription, dismantling of the nucleosomal organization, and histone to protamine transition. This process is unique to the male germ line. Mouse models have shown that defects in nuclear condensation lead to male infertility; however, the mechanisms regulating this complex genome-wide process are not well understood. Our working hypothesis is that the genome organizer protein CTCF coordinates the chromatin remodeling events accompanying spermatid differentiation. The evolutionarily conserved eleven zinc finger protein CCCTC-binding factor (CTCF) is exclusively expressed within the round and early elongating spermatids in mice, coinciding with transcriptional shutdown and the onset of histone replacement. In this pilot, feasibility grant proposal we will test the hypotheses that: 1) CTCF functions as a transcription factor as well as an organizer of spermatid genome to facilitate chromatin remodeling and 2) CTCF is essential for the completion of spermatogenesis and male fertility. We will perform ChIP-seq to determine genome-wide occupancy of CTCF in round spermatids and generate CTCF conditional knockout mice using the Cre-loxP technology to test the requirement of CTCF for spermatogenesis and male fertility. CTCF is an ideal candidate for this role because it is a multifunctional DNA binding protein with diverse roles including that of a chromatin organizer. Floxed CTCF mice as well as the male germ cell-specific cre-deleter strain (Stra8-iCre) are readily available. This proposal will explore the role of CTCF in male fertility fr the first time. Infertility affects 1 in 6 couples in the reproductive age group, with the male facor accounting for 50% of those cases. If depletion of CTCF causes sperm maturation arrest, this study will provide a novel mouse model for male infertility. Given the role that CTCF plays in establishing and / or maintaining epigenetic marks, the proposed knockout mouse may be a useful model to understand the risks involved in Assisted Reproductive Technology using incompletely developed spermatids or sperm. Thus, the studies are highly significant from the point of view of male reproductive health.

描述（由申请人提供）：圆形精子细胞分化为精子，称为精子发生，是一个复杂的过程，涉及顶体、鞭毛和细胞核的浓缩。在准备浓缩时，精子细胞核经历戏剧性的染色质。重塑包括全基因组转录的停止、核小体组织的解体以及组蛋白向鱼精蛋白的转变，这个过程是独特的。小鼠模型表明核凝结缺陷会导致雄性不育；然而，我们的工作假设是基因组组织蛋白 CTCF 协调染色质重塑。进化上保守的 11 种锌指蛋白 CCCTC 结合因子 (CTCF) 在小鼠的圆形和早期伸长的精子细胞中专门表达，与转录关闭和精子细胞分化的开始同时发生。在这个试点可行性拨款提案中，我们将测试以下假设：1) CTCF 作为转录因子以及精子基因组的组织者以促进染色质重塑，2) CTCF 对于精子发生和雄性的完成至关重要。我们将对圆形精子细胞中 CTCF 的全基因组占有率进行 ChIP-seq，并使用 Cre-loxP 技术生成 CTCF 条件敲除小鼠，以测试 CTCF 的需求以确定生育能力。 CTCF 是这种作用的理想候选者，因为它是一种多功能 DNA 结合蛋白，具有多种作用，包括染色质组织者以及雄性生殖细胞特异性 cre 删除菌株 (Stra8-)。 iCre）是现成的，该提案将首次探讨 CTCF 在男性生育力中的作用。不育症影响着六分之一的育龄夫妇，其中男性因素占 50%。如果 CTCF 的消耗导致精子成熟停滞，鉴于 CTCF 在建立和/或维持表观遗传标记中的作用，本研究将为男性不育症提供一种新的小鼠模型。了解使用未完全发育的精子细胞或精子的辅助生殖技术所涉及的风险因此，从男性生殖健康的角度来看，这些研究具有非常重要的意义。