Mechanisms of transgenerational epigenetic inheritance

跨代表观遗传机制

基本信息

批准号：
9899105
负责人：
Victor G. Corces
金额：
$ 34.73万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-04-01 至 2022-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9899105
关键词：
3-Dimensional ATAC-seq Adipocytes Adult Affect Antibodies Architecture Binding Binding Sites Cell Differentiation process Cell Nucleus ChIP-seq Chromatin Chromosomes Complex DNA DNA Methylation DNA-Binding Proteins Data Development Enhancers Environment Environmental Risk Factor Epigenetic Process Exposure to Female Fertilization Frequencies Gene Expression Generations Genes Genetic Transcription Genome Germ Lines Histones Human Hypersensitivity Individual Link Location Maintenance Mammals Maps Mass Spectrum Analysis Mediating Mediator of activation protein Metabolic Diseases Modification Mus Nature Nucleosomes Obese Mice Obesity Onset of illness Outcome Paint Parents Pattern Phenotype Positioning Attribute Pregnancy Procedures Protamines Proteins Protocols documentation RNA Polymerase II Resolution Site Somatic Cell Spermatids Spermatogenesis Spermiogenesis Structure of primordial sex cell Suggestion Techniques Tissues Transcription Alteration Transcription Initiation Site Untranslated RNA Work base bisphenol A bisulfite sequencing chromosome conformation capture cohesin condensin embryo cell epigenome experimental study histone modification insight male mouse model next generation novel offspring pluripotency pregnant sperm cell stem cells transcription factor transcriptome sequencing transgenerational epigenetic inheritance transmission process

项目摘要

Project Summary/Abstract Environmental factors increase the frequency of metabolic disorders. The mechanisms by which these epiphenotypes are transmitted between the exposed and subsequent generations through the paternal germline remains poorly understood. The nuclei of mammalian sperm are highly condensed, the DNA is mostly covered by protamines with only a few retained nucleosomes, and epigenetic information stored in the form of DNA methylation is quickly erased from paternal chromosomes shortly after fertilization. Experiments carried out in our lab suggest a more complex picture of mouse sperm, suggesting the presence of multiple histone modifications, nucleosomes positioned around transcription start sites and transcription factor binding sites, presence of CTCF, cohesin, condensin, FoxA1, Oct4, Nanog, Mediator and RNAPII phosphorylated in Ser2. We also find thousands of enhancers and super-enhancers in a poised or active epigenetic state based on the presence of both specific histone modifications and transcription factors. This information suggests that mammalian sperm contain a rich and complex palette of epigenetic information that could be altered by environmental factors to paint novel phenotypic outcomes in the next generation. In this application, we propose to carry out experiments to dissect the mechanisms by which epigenetic information is established and altered by the environment during male germline development, how this information is stored in sperm, and how it is transmitted to the somatic cells of adult tissues of the next generation. To accomplish this we will use obese mice who are 4th generation descendants of females exposed to Bisphenol A (BPA) during pregnancy. We will use mass spectrometry to identify a wide range of transcription factors present in sperm, and ChIP-seq to examine differences in the distribution of these transcription factors in the sperm of control versus obese mice. We will then use Chromosome Conformation Capture techniques to examine the consequence of alterations in transcription factor binding on the 3D architecture of mouse sperm. To understand how and when differences in the epigenome of control and obese mice are established, we will examine the effect of BPA treatment on transcription and transcription factor distribution using RNA-seq, ATAC-seq and ChIP-seq in primordial germ cells and spermatogonial stem cells. Similar analyses will be performed in adipocytes of obese mice in order to understand which of these epigenetic alterations are maintained in adult tissues and may be responsible for the observed obese phenotype. Results from this work will give critical insights into the mechanisms by which alterations in the epigenome are established and transmitted between generations.

项目概要/摘要环境因素会增加代谢紊乱的发生频率。其机制这些表型在暴露者和后代之间通过对父系种系仍知之甚少。哺乳动物精子的细胞核高度浓缩后，DNA 大部分被鱼精蛋白覆盖，仅保留少量核小体，以 DNA 甲基化形式储存的表观遗传信息很快就会从父系中删除受精后不久染色体。我们实验室进行的实验表明更多小鼠精子的复杂图片，表明存在多种组蛋白修饰，核小体位于转录起始位点和转录因子结合位点周围，存在 CTCF、cohesin、condensin、FoxA1、Oct4、Nanog、Mediator 和 RNAPII Ser2 磷酸化。我们还发现了数以千计的增强子和超级增强子或基于特定组蛋白修饰的存在的活跃表观遗传状态和转录因子。这一信息表明哺乳动物的精子含有丰富且复杂的表观遗传信息调色板可能会因环境因素而改变以进行绘画下一代的新表型结果。在本申请中，我们建议执行剖析表观遗传信息建立机制的实验在雄性种系发育过程中受到环境的改变，这些信息如何存储在精子，以及它如何传递到下一代成体组织的体细胞。到为了实现这一目标，我们将使用肥胖小鼠，它们是暴露的雌性小鼠的第四代后代怀孕期间接触双酚 A (BPA)。我们将使用质谱法来识别广泛的精子中存在的转录因子，并通过 ChIP-seq 检查分布差异对照小鼠与肥胖小鼠精子中这些转录因子的比较。然后我们将使用染色体构象捕获技术可检查染色体构象改变的结果转录因子与小鼠精子 3D 结构的结合。了解如何以及当对照小鼠和肥胖小鼠的表观基因组差异确定后，我们将检查使用 RNA-seq 观察 BPA 处理对转录和转录因子分布的影响，原始生殖细胞和精原干细胞中的 ATAC-seq 和 ChIP-seq。相似的将在肥胖小鼠的脂肪细胞中进行分析，以了解其中哪些表观遗传改变在成体组织中得以维持，并且可能是观察到的现象的原因肥胖表型。这项工作的结果将为我们提供重要的见解表观基因组的改变是确定的并在代际间传递。