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节密切相关。染色质 重塑是指真核染色体的动态压实和反应 通过核小体的共价修饰和物理运动。了解 驱动重塑的过程对于获得对人类的更深入的理解至关重要 正常基因调节（例如癌症）和遗传的破坏导致的疾病 发育障碍。关于ATP的机制，相对鲜为人知 依赖重塑因子改变了核小体的结构，但不了解 重塑域在功能上相互作用以促进重塑，密钥重塑域是如何 相对于彼此，位于太空中，也不是重塑器如何包含核小体 基材。 该提案的长期目标是建立生化和生物物理 描述和理解染色质重塑过程所需的框架。这 建议重点是CHD1染色质重塑因子，具体目的是（1）剖析 CHD1重塑周期通过表征部分功能失调的变体，（2）确定 使用X射线晶体学的CHD1重塑仪的结构，（3）确定组织 CHD1：使用小角度X射线散射（SAXS）和DNA足迹的核小体复合物。经过 CHD1与通过X射线晶体学获得的结构信息的耦合功能研究， SAXS和DNA足迹，我们期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学至关重要 该操纵全基因组基因表达以治疗人类疾病。人体几乎所有细胞都具有相同的基因，但只有一部分 这些基因在任何特定的组织中都被打开。基因的“ ON”和“ OFF”状态 以复杂且定义不明的方式调节，直接与 染色体的物理包装，称为染色质结构。了解 可以通过所谓的染色体打开和重新包装染色体的过程 染色质重塑因子对于理解和作战是必要的 基因表达失衡的许多疾病，例如癌症。