Structural and Functional Analysis of the Chd1 Chromatin Remodeler

Chd1 染色质重塑剂的结构和功能分析

• 批准号: 9912780
• 负责人: GREGORY DEAN BOWMAN
• 金额: $ 40.42万
• 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 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9912780
• 关键词: 2-Aminopurine; ATP phosphohydrolase; ATPase Domain; Architecture; Back; Behavior; Bypass; CHD1 gene; Cell physiology; Chromatin; Chromatin Loop; Communication; Complex; Coupled; Crystallization; DNA; DNA Binding; DNA Binding Domain; DNA Polymerase II; DNA Repair; DNA Sequence; DNA Structure; DNA biosynthesis; DNA-Directed RNA Polymerase; Dissociation; Enzymes; Family; Fluorescence; Genes; Genetic Transcription; Genome; Growth and Development function; Health; Histones; Human; ISWI; Link; Maintenance; Malignant Neoplasms; Measures; Modeling; Molecular Conformation; Monitor; Motor; Movement; Mutagenesis; Mutation; Nature; Normal Cell; Nucleosomes; Outcome; Play; Positioning Attribute; Process; Regulation; Resistance; Role; Single-Stranded DNA; Site; Slide; Sodium Chloride; Structure; Surface; Testing; Work; cancer type; cell growth; chromatin remodeling; crosslink; developmental disease; dimer; experimental study; follow-up; helicase; human disease; insight; melting; physical process; pluripotency; response; sensory mechanism; single-molecule FRET; stem cells; transcription factor; translocase

ABSTRACT Chromatin remodelers are ATP-dependent DNA translocases that catalyze disassembly, reassembly, and repositioning of nucleosomes throughout eukaryotic genomes. As evidenced from multiple types of cancer and developmental disorders associated with remodeler inactivation, chromatin remodeling is essential for normal growth and development. Remodeling requires transient and controlled disruption of histone-DNA interactions, with different families of remodelers possessing unique domains thought to assist or regulate action of a conserved ATPase motor. Our crystal structure of the Chd1 chromatin remodeler provided the first view of ATPase motor regulation, showing how a DNA-binding surface of the ATPase motor was blocked by adjacent chromodomains. As seen from work with the ISWI remodeler family, the auto-inhibitory nature of the Chd1 chromodomains has proven to be a common strategy for regulating ATPase action on the nucleosome. However, it remains unclear how such domain-domain interactions enable remodelers to sense and respond to particular nucleosome substrates, or achieve unique remodeling outcomes. Here we follow up our recent discoveries of Chd1 architecture on the nucleosome, where the Chd1 DNA-binding domain was found to directly communicate with the chromo-ATPase across the gyres of the nucleosome. We propose to test the hypothesis that inter-domain interactions of Chd1 are responsible for sensing DNA outside the nucleosome and that domains work together to achieve particular remodeling outcomes. In addition to remodeler regulation, the mechanism by which chromatin remodelers reposition nucleosomes along DNA is also poorly understood. Intriguing single molecule FRET experiments with the ISWI remodeler have revealed step-like and discontinuous movements DNA, suggesting that DNA behaves as a spring on the nucleosome. We will test this idea and further investigate DNA interactions needed for high processive steps that we also observe for Chd1. Together, these studies will provide new mechanistic insights into how chromatin remodelers manipulate the structure of the nucleosome and use domain-domain communication to regulate remodeler action. !

抽象的 染色质重塑剂是 ATP 依赖性 DNA 转位酶，可催化分解、重组和 整个真核基因组中核小体的重新定位。多种类型的癌症和 与重塑蛋白失活相关的发育障碍，染色质重塑对于正常发育至关重要 成长和发展。重塑需要组蛋白-DNA 相互作用的瞬时和受控破坏， 不同的重塑者家族拥有独特的领域，被认为可以帮助或调节一个 保守的 ATP 酶马达。我们的 Chd1 染色质重塑者的晶体结构提供了第一个视图 ATP 酶运动调节，显示 ATP 酶运动的 DNA 结合表面如何被相邻的阻断 染色质结构域。从与 ISWI 重塑家族的合作中可以看出，Chd1 的自动抑制性质 染色质结构域已被证明是调节 ATP 酶对核小体作用的常见策略。 然而，目前尚不清楚这种域与域之间的交互如何使重构者能够感知和响应 特定的核小体底物，或实现独特的重塑结果。下面我们就来跟进一下最近的情况 核小体上 Chd1 结构的发现，其中 Chd1 DNA 结合域被发现 穿过核小体的环路直接与染色体 ATP 酶通讯。我们建议测试 假设 Chd1 的域间相互作用负责感知核小体外的 DNA 并且这些领域共同努力以实现特定的重塑结果。 除了重塑因子的调节之外，染色质重塑因子重新定位核小体的机制 人们对DNA的了解也知之甚少。使用 ISWI 重塑器进行有趣的单分子 FRET 实验 揭示了DNA的阶梯状和不连续的运动，表明DNA的行为就像一个弹簧 核小体。我们将测试这个想法并进一步研究高处理步骤所需的 DNA 相互作用 我们也观察到 Chd1。总之，这些研究将提供新的机制见解 染色质重塑者操纵核小体的结构并使用域间通信来 规范改造者的行为。 ！