Dynamics of Cardiac Nuclei in Heart Disease

项目总结/摘要 虽然基因组的序列在不同的细胞类型中是不变的，但它的功能却有很大的不同。因此，在本发明中， 表观基因组由组蛋白变异体、DNA修饰、染色质结构蛋白组成， 添加、去除和解释翻译后修饰的蛋白质骨干，对于 了解心脏和其他细胞类型的功能。一个具有基本和转化影响的关键问题 心脏生理学的核心问题是：细胞如何维持正确的染色质环境， 成人肌细胞转录组 在这种更新的初步研究中，我们已经采用了染色质构象分析方法， 在成年心肌细胞中起作用。我们绘制了心肌细胞中的拓扑关联结构域（TADs）， 基础和压力过载的心脏，确定染色质可及性和基因分配的区域 根据拓扑结构分为活跃和不活跃的区域RNA-seq研究已经在这些相同的基因组中进行。 模型来理解对转录的影响。从机理上讲，我们已经揭示了染色质的作用， 表观基因组规范中的结构蛋白，与我们对染色质的全球测量一起， 可及性和基因表达，作为这项赠款的科学前提。此外，我们还开发了 技术，以确定，与个别位点特异性，如何这些蛋白质（包括高流动性 组成员HMGB 2，HMGA 1和HMGN 5，加上Nap 1和其他通过蛋白质组学鉴定的）控制局部 通过与其他组蛋白标志物的相互作用来实现可及性和转录。 我们假设染色质结构是环境压力的主要整合者 以及所有常见疾病的另一个主要决定因素：群体规模遗传变异性。我们提出 三个目的来验证这一假设：首先，我们将确定基本的结构-功能关系， 使用Hi-C和RNA-seq的健康和患病心脏中的心脏表观基因组。第二，我们将确定 通过染色质结构蛋白在单个基因座使用以下组合进行转录调控的逻辑： 靶向染色质可及性分析、蛋白质组学、ChIP-seq和功能获得/丧失。第三，我们将确定 并验证表观基因组内的功能基序，揭示遗传变异如何与差异结合， 蛋白质结合以指定整个人群中的改变的转录，从而心脏表型。

PROJECT SUMMARY/ABSTRACT While the sequence of the genome is invariant across cell types, its function varies widely. As a result, the epigenome, which is composed of histone variants, DNA modification, chromatin structural proteins, and the cadre of proteins that add, remove and interpret post-translational modifications, is of principle importance to understanding the function of cardiac and other cell types. A critical question with basic and translational impact in cardiac physiology is: how does the cell maintain the correct chromatin environment conducive to a healthy adult myocyte transcriptome? In preliminary studies for this renewal, we have adapted methods for chromatin conformation analysis to work in adult cardiac myocytes. We have mapped topologically associating domains (TADs) in myocytes from the basal and pressure overloaded heart, identifying regions of chromatin accessibility and partitioning of genes into active and inactive compartments based on topology. RNA-seq studies have been carried out in these same models to understand the impact on transcription. Mechanistically, we have revealed the actions of chromatin structural proteins in epigenomic specification, which, together with our global measurements of chromatin accessibility and gene expression, serve as the scientific premise for this grant. In addition, we have developed the techniques to determine, with individual locus specificity, how these proteins (including the high mobility group members HMGB2, HMGA1 and HMGN5, plus Nap1 and others identified by proteomics) control local accessibility and transcription through the interaction with other histone marks. We hypothesize that chromatin structure serves as a principal integrator of environmental stress and the other major determinant of all common disease: population scale genetic variability. We propose three aims to test this hypothesis: first, we will determine the fundamental structure-function relationship of the cardiac epigenome in the healthy and diseased heart using Hi-C and RNA-seq. Second, we will determine the logic for transcriptional regulation by chromatin structural proteins at individual loci using a combination of targeted chromatin accessibility analysis, proteomics, ChIP-seq and gain/loss of function. Third, we will identify and validate functional motifs within the epigenome, revealing how genetic variation combines with differential protein binding to specify altered transcription, and thus cardiac phenotype, across a population.