Mechanism for loading the E. coli beta clamp on DNA

DNA 上大肠杆菌 beta 钳的加载机制

• 批准号: 7051413
• 负责人: SARAH Katharine SCOUTEN
• 金额: $ 2.54万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-02 至 2008-04-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7051413
• 关键词: DNA binding protein; DNA directed DNA polymerase; DNA repair; DNA replication; Escherichia coli; adenosine triphosphate; autoradiography; bacterial DNA; bacterial proteins; conformation; dimer; electrophoresis; gel filtration chromatography; nucleoproteins; predoctoral investigator; protein binding; protein folding; protein protein interaction; protein structure; site directed mutagenesis

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand how organisms coordinate the replication and repair of their genomes. The use of processivity clamps that must be loaded onto DNA during replication of chromosomes by an ATP dependent clamp loader complex is highly conserved by all forms of life. Understanding how organisms coordinate DNA replication and repair is the fundamental basis for understanding human diseases such as cancer. The goal of the work proposed here is to better define the mechanism of clamp loading in the E. coli model system. The E. coli clamp loader (gamma complex) is a multisubunit complex that undergoes a conformational change upon binding ATP which facilitates opening of the beta clamp and its subsequent loading onto DNA. The contacts of the individual clamp loader subunits with beta differ between the ATP bound and free states of gamma complex. The interactions of the gamma complex subunits with beta in both the presence and absence of ATP will be determined. Biochemical assays using various clamp and clamp loader mutants will be utilized to accomplish this. The insight gained from E. coli can provide a framework for elucidating the mechanisms of eukaryotes, including humans.

描述（由申请人提供）：这项研究的长期目标是了解生物如何协调其基因组的复制和修复。 在通过ATP依赖夹具装载机复合物复制染色体过程中，必须将加工夹具加载到DNA上的加工性夹具的使用高度保守了所有形式的生命。 了解生物如何协调DNA复制和修复是理解人类疾病（例如癌症）的基本基础。 这里提出的工作的目的是更好地定义大肠杆菌模型系统中夹紧载荷的机制。 大肠杆菌夹具装载机（伽马络合物）是一种多生育复合物，在结合ATP时会发生构象变化，从而促进β夹的打开及其随后的载荷到DNA上。 具有β的单个夹具加载子亚基的接触在伽马络合物的ATP结合和游离状态之间有所不同。在ATP的存在和不存在的情况下，伽马复合物亚基与β的相互作用将被确定。 使用各种夹具和夹具装载机突变体的生化测定将用于实现这一目标。从大肠杆菌中获得的洞察力可以提供一个框架，以阐明包括人类在内的真核生物的机制。