Structural and Functional Analysis of the CHD1 Chromatin Remodeler

CHD1 染色质重塑蛋白的结构和功能分析

• 批准号: 8248770
• 负责人: GREGORY DEAN BOWMAN
• 金额: $ 27.86万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8248770
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Architecture; Binding; Biochemical; C-terminal; Cells; Chromatin; Chromatin Remodeling Factor; Chromatin Structure; Chromosome Structures; Chromosomes; Communication; Complex; Congenital Abnormality; Coupling; DNA; DNA Binding; DNA Footprint; Disease; Docking; Elements; Enzymes; Future; Gene Expression; Gene Expression Regulation; Gene Silencing; Genes; Genome; Goals; Histones; Human body; Hydrolysis; Individual; Inherited; Knowledge; Link; Malignant Neoplasms; Measurement; Modeling; Modification; Molecular; Molecular Profiling; Motion; Movement; N-terminal; Nucleosomes; Pattern; Play; Positioning Attribute; Process; Proteins; Reaction; Relative (related person); Resolution; Roentgen Rays; Role; Site-Directed Mutagenesis; Slide; Staging; Structure; Surface; Techniques; Therapeutic; Tissues; Variant; Work; X-Ray Crystallography; chromatin remodeling; combat; design; developmental disease; genome-wide; human disease

The physical organization of chromosomes is intimately tied to gene regulation. Chromatin remodeling refers to the dynamic compaction and decondensation of eukaryotic chromosomes through the covalent modification and physical movement of nucleosomes. Knowledge of the processes that drive remodeling are essential for gaining a more insightful understanding of human diseases that result from disruptions of normal gene regulation, such as cancer and inherited developmental disorders. Relatively little is known regarding the mechanism of by which ATP- dependent remodeling factors alter nucleosome structure, with no understanding of how distinct remodeler domains functionally interact to promote remodeling, how key remodeler domains are positioned in space with respect to one another, nor how remodelers embrace the nucleosome substrate. The long-term objective of this proposal is to establish a biochemical and biophysical framework necessary for describing and understanding the process of chromatin remodeling. This proposal focuses on the CHD1 chromatin remodeling factor, with specific aims to (1) dissect the CHD1 remodeling cycle by characterizing partially dysfunctional variants, (2) determine the architecture of the CHD1 remodeler using X-ray crystallography, and (3) determine the organization of a CHD1:nucleosome complex using small angle X-ray scattering (SAXS) and DNA footprinting. By coupling functional studies of CHD1 with structural information gained through X-ray crystallography, SAXS, and DNA footprinting, we expect to elucidate key steps of the remodeling reaction. In the future, a deeper understanding of chromatin remodeling will be essential for developing therapeutics that manipulate genome-wide gene expression for treatment of human disease. Nearly all cells in the human body possess the same set of genes, yet only a subset of these genes are turned "on" in any particular tissue. The "on" and "off" states of genes are regulated in a complex and ill-defined manner that directly correlates with the physical packaging of chromosomes, called the chromatin structure. Understanding the process by which chromosomes can be unpackaged and repackaged by so-called chromatin remodeling factors is necessary for understanding and therefore combatting many diseases such as cancer where there are imbalances in gene expression.

染色体的物理组织与基因调控密切相关。染色质 重塑是指真核染色体的动态压缩和解压缩 通过核小体的共价修饰和物理运动。的知识 推动重塑的过程对于更深入地了解人类至关重要 由于正常基因调控破坏而导致的疾病，例如癌症和遗传性疾病 发育障碍。关于 ATP 的作用机制，人们知之甚少。 依赖的重塑因子改变核小体结构，但不了解其差异有多大 重塑者域在功能上相互作用以促进重塑，重塑者域的关键性如何 相对于彼此在空间中的定位，以及重塑者如何拥抱核小体 基材。 该提案的长期目标是建立一个生物化学和生物物理 描述和理解染色质重塑过程所必需的框架。这 提案重点关注 CHD1 染色质重塑因子，具体目标是 (1) 剖析 CHD1 重塑周期通过表征部分功能失调的变异，(2) 确定 使用 X 射线晶体学的 CHD1 重塑器的架构，以及 (3) 确定 使用小角 X 射线散射 (SAXS) 和 DNA 足迹分析的 CHD1：核小体复合物。经过 将 CHD1 的功能研究与通过 X 射线晶体学获得的结构信息结合起来， SAXS 和 DNA 足迹分析，我们希望阐明重塑反应的关键步骤。在 未来，对染色质重塑的更深入了解对于开发治疗方法至关重要 操纵全基因组基因表达来治疗人类疾病。人体中几乎所有细胞都拥有相同的基因组，但只有一个子集 这些基因在任何特定组织中都会“打开”。基因的“开”和“关”状态 以复杂且不明确的方式进行监管，与 染色体的物理包装，称为染色质结构。了解 染色体可以通过所谓的解包和重新包装的过程 染色质重塑因子对于理解并因此对抗是必要的 许多疾病，例如癌症，都存在基因表达失衡。