Investigating the contribution of paternal nucleosomes using the Gcn5 knock-out mouse

使用 Gcn5 敲除小鼠研究父本核小体的贡献

基本信息

批准号：
10303551
负责人：
Lacey J Luense
金额：
$ 8.13万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-21 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10303551
关键词：
ATAC-seq Affect Animal Model Applications Grants Cell Nucleus Chromatin Clinical Clinical Management Complement Couples DNA DNA Structure Data Development Diagnosis Embryo Embryonic Development Ensure Epigenetic Process Ethics Event Exhibits Fertility Fertilization Future Genetic Transcription Genome Genomics Germ Cells Grant Histones Human Infertility Intracytoplasmic Sperm Injections Investigation Kinetics Knockout Mice Knowledge Laboratory Research Lead Male Infertility Mediator of activation protein Meiosis Modeling Mutant Strains Mice Nucleosomes Patients Placentation Play Pre-implantation Embryo Development Pregnancy loss Process Protamines Proxy Recurrence Research Role Spermatocytes Spermatogenesis Spermiogenesis Testing United States Work blastocyst epigenetic regulation epigenome experimental study feasibility testing genomic tools healthy pregnancy histone acetyltransferase human male implantation insight male model development mouse model mutant mouse model non-genetic novel offspring promoter sperm cell transcriptome transcriptome sequencing

项目摘要

ABSTRACT Infertility affects approximately 15% of couples in the United States, with males contributing in nearly 50% of these cases. One potential mechanism underlying infertility are alterations to the paternal epigenome. Mammalian spermatozoa exhibit a unique, highly compacted and condensed DNA structure that is strongly dependent on epigenetic mechanisms, including histone hyperacetylation followed by nucleosome eviction. Specifically, 90-99% of sperm nucleosomes are evicted and replaced with protamines, allowing for this remarkable degree of compaction. Human sperm exhibiting altered ratios of protamines or excess histone retention are associated with infertility and altered embryogenesis following IVF/ICSI. However, the exact cause of altered embryogenesis as a result of abnormal nucleosome retention, and ultimately, potential regulatory functions and mechanisms by which paternally contributed histones affect early development, remain largely unknown. We have previously developed a conditional mouse mutant where the histone acetyltransferase Gcn5 is ablated in pre-meiotic germ cells (Gcn5cKO). One relevant feature of this model is that mature sperm have increased histone retention and decreased fertility. This model provides the ability to study the effect of paternal nucleosome contributions to the embryo, and determine the consequences of abnormal paternal nucleosome contribution on embryonic development. We propose that the paternal epigenome, specifically nucleosomes, play a role in regulating early embryonic chromatin and transcriptional dynamics, thus leading to proper embryonic development. We will utilize our Gcn5cKO mouse model to introduce an abnormal complement of sperm nucleosomes into embryos and investigate the following Specific Aims: (1) To determine if excess paternal nucleosomes alter the kinetics and successful development of pre-implantation embryos and (2) determine if abnormally retained paternal nucleosomes alter chromatin dynamics and transcription in pre-implantation embryos. Together, the proposed research will provide important insight into the mechanisms governing early embryonic development, including the effects of the paternal epigenome on chromatin dynamics and zygotic genome activation. It will additionally provide evidence as to why abnormal paternal chromatin results in infertility and altered embryogenesis in humans. The results of these studies have the potential to ultimately impact clinical management of patients diagnosed with infertility.

抽象的不育会影响美国约15％的夫妇，男性几乎贡献这些案件中有50％。不育的一种潜在机制是对父亲表观基因组的改变。哺乳动物精子表现出独特的，高度压实和凝结的DNA结构，强烈取决于表观遗传机制，包括组蛋白高乙酰化，然后进行核小体驱逐。具体而言，90-99％的精子核小体被驱逐并用精蛋白代替，从而使这显着的压实程度。人类精子表现出改变了精蛋白或过量组蛋白的比例改变保留与不育和胚胎发生后的胚胎发生有关。但是，确切的由于核小体保留异常而导致胚胎发生的原因改变，最终是潜在的父亲贡献组蛋白会影响早期发育的调节功能和机制，在很大程度上未知。我们以前已经开发了一个有条件的小鼠突变体，其中组蛋白乙酰基转移酶GCN5在求生生殖细胞（GCN5CKO）中被消融。该模型的一个相关功能是成熟的精子增加了组蛋白的保留率并降低了生育能力。该模型提供了能力研究父亲核小体对胚胎的贡献的影响，并确定父亲核小体对胚胎发育的贡献。我们建议父亲表观基因组，特别是核小体，在调节早期胚胎染色质和转录动力学，从而导致适当的胚胎发育。我们将利用我们的GCN5CKO小鼠模型引入精子核小体的异常补体进入胚胎并研究以下特定目的：（1）确定父亲是否过多改变动力学和成功开发植入前胚胎，（2）确定是否异常保留的父亲核小体改变了植入前胚胎中的染色质动力学和转录。拟议的研究将共同提供有关早期胚胎的机制的重要见解发育，包括父亲表观基因组对染色质动力学和合子基因组的影响激活。它还将提供证据表明为什么父亲染色质异常导致不育症和人类的胚胎发生改变。这些研究的结果有可能最终影响临床诊断患有不育的患者的管理。