Histone Tail Interactions and Functions in Chromatin

染色质中组蛋白尾部的相互作用和功能

基本信息

批准号：
8197825
负责人：
Jeffrey J Hayes
金额：
$ 31.67万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
1995
资助国家：
美国
起止时间：
1995-05-01 至 2012-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8197825
关键词：
Acetylation Address Affect Affinity Binding Biological Assay Cell Nucleus Cells Chemicals Chromatin Chromatin Fiber Chromatin Modeling Chromatin Remodeling Factor Chromatin Structure Complex DNA Disease Elements Enzymes Eukaryotic Cell Gene Abnormality Gene Expression Gene Expression Regulation Genes Genetic Transcription Genome Glutamine Goals Grant HMGN Proteins HMGN1 gene Hereditary Disease Higher Order Chromatin Structure Histone Acetylation Histone H1 Histone H1(s)Histone H3 Histone H4 Histones Human Individual Label Lasers Lead Length Life Link Location Lysine Malignant Neoplasms Maps Methods Modeling Modification Molecular Mutation Nuclear Nucleosome Core Particle Nucleosomes Physical condensation Play Post-Translational Protein Processing Process Proteins Role Secondary to Signal Transduction Site Sodium Chloride Structure Tail Techniques Testing Tetrahymena Work abstracting base cancer genetics chromatin remodeling crosslink novel novel strategies reconstitution research study transcription factor

项目摘要

Abstract: DNA within the eukaryotic cell nucleus is assembled with histones and other proteins to form a complicated, multifaceted complex known as chromatin. Chromatin not only serves to package the genome but elements of chromatin structure have been intimately integrated into gene control mechanisms. The core histone tail domains are essential for the formation of multiple levels of structure within chromatin and a large portion of signal transduction within the nucleus ultimately directs posttranslational modification of these domains in order to facilitate nuclear processes such as transcription. In several cases, mutations in enzymes that carry out these modifications have been linked to various diseases including cancers in humans. However, the molecular mechanisms by which the tail domains define chromatin structures - and ultimately the functionality of the underlying DNA - remain poorly understood. The primary goal of the work described in this proposal is to elucidate the molecular mechanisms by which the core histone tail domains dictate the formation of higher order chromatin structures and how acetylation of specific lysines within these domains alters tail structures and interactions to allow for gene expression. Our aims are to 1) characterize short-range and long-range inter- nucleosomal interactions of the H3 and H4 tail domains in model nucleosomes and nucleosome arrays, 2) Determine whether linker histone H1, the architectural transcription factor HMGN or a chromatin remodeling activity specifically alters interactions of the tail domains and to 3) quantitatively assess binding of selected tail domains and the effect of acetylation on these interactions in reconstituted and native chromatin. We will use several novel approaches including site-directed chemical mapping of tail-DNA interactions, a UV laser crosslinking approach, and other chemical probing approaches to investigate structures and interactions of the tail domains. Further, we will use a chemical protection approach and NMR of specifically labeled core histones to quantitatively assess the salt-dependent binding stability of individual histone tails within nucleosomes. This work will advance our understanding of critical molecular mechanisms that impinge upon control of gene expression and ultimately diseases such as cancer.

抽象的：真核细胞核内的DNA与组蛋白和其他蛋白质组装成形成复杂的多面复合物，称为染色质。染色质不仅用于包装基因组，但染色质结构的元素已密切相关整合到基因控制机制中。核心组蛋白尾域对于在染色质和大部分信号内形成多个结构的形成细胞核内的转导最终指导这些后翻译后修饰域以促进核过程，例如转录。在某些情况下，进行这些修饰的酶突变已与各种包括人类癌症在内的疾病。但是，分子机制尾部结构域定义染色质结构 - 最终潜在的DNA-仍然很了解。描述的工作的主要目标该建议是阐明核心组蛋白尾巴的分子机制结构域决定了高阶染色质结构的形成以及乙酰化的形成这些域中的特定赖氨酸的特定赖氨酸改变了尾巴结构和相互作用以允许基因表达。我们的目标是1）表征短期和远程间模型核小体和H4尾域的核小体相互作用和核小体阵列，2）确定接头组蛋白H1是否是建筑转录因子HMGN或染色质重塑活性特异性改变尾部结构域的相互作用和3）定量评估选定尾巴的结合域以及乙酰化对重构和天然中这些相互作用的影响染色质。我们将使用几种新型方法，包括定向化学物质尾巴相互作用的映射，紫外线激光交联方法和其他化学物质探测方法来研究尾部结构域的结构和相互作用。此外，我们将使用一种化学保护方法和特异性标记核心的NMR 组蛋白用于定量评估单个组蛋白的盐依赖性结合稳定性核小体内的尾巴。这项工作将提高我们对关键分子的理解影响控制基因表达并最终疾病的机制作为癌症。