Structural Studies of Nucleoprotein Complexes

核蛋白复合物的结构研究

• 批准号: 7373488
• 负责人: EDWARD H. EGELMAN
• 金额: $ 30.39万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-04-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7373488
• 关键词: ATP phosphohydrolase; Accounting; Address; Affinity; Archaea; Archaeal Proteins; Area; BRCA2 gene; Bacteria; Binding; Biochemical Genetics; Biological Models; Cells; Clock protein; Complex; Crystallography; DNA; DNA Binding; DNA Damage; DNA Repair; DNA biosynthesis; Data; Defect; Dimensions; E coli RecA protein; Electron Microscopy; Electrons; Escherichia coli; Essential Genes; Eukaryota; Eukaryotic Cell; Filament; Fission Yeast; Funding; Genetic; Genetic Recombination; Genetic Variation; Genome Stability; Germ-Line Mutation; Goals; Grant; Hand; Hereditary Breast Carcinoma; Homologous Gene; Human; Image Analysis; Individual; Ionizing radiation; Knowledge; MCM Protein; Maintenance; Malignant Neoplasms; Meiosis; Methods; Microscopic; Modeling; Nucleoproteins; Pathway interactions; Play; Polymers; Population; Proteins; Pump; Rec A Recombinases; Resistance; Resolution; Role; Sasa; Site; Streptococcus pneumoniae; Stress; Structural Protein; Structure; Thinking; Time; Work; Yeasts; circadian pacemaker; helicase; image processing; improved; interest; migration; monomer; polymerization; prevent; protein function; protein structure; recombinational repair; reconstruction; tumorigenesis

DESCRIPTION (provided by applicant): Homologous genetic recombination is responsible, in part, for the introduction of genetic diversity within a population. This diversity is essential to the long-term viability of that population under many different stresses and challenges. Homologous genetic recombination is now also widely accepted as one of the mechanisms of DNA repair within individuals, and defects in the recombination/repair pathways have been tied to genetic instability and cancers. The bacterial RecA protein has been one of the main model systems for understanding homologous genetic recombination, and we know that the human RAD51 and Dmc1 proteins are structural homologs of RecA that play key roles in DNA repair and meiosis, respectively. However, our detailed knowledge of the manner in which these proteins actually function in catalyzing the recognition of homology between different molecules and in strand exchange is quite limited, in part because we only have high resolution structures for components, and low resolution structures for the functional assemblies. We will greatly extend our existing electron microscopic studies of RecA and RAD51 filaments through applications of the unique image processing method that we have developed for studying helical polymers. We have the ability to look at the complexes formed by these proteins on DNA, while such complexes cannot be directly studied by crystallography or NMR. We will also use electron microscopy and image analysis to study ring complexes, such as helicases and branch migration pumps, that act in many areas of DNA replication, recombination and repair. Specifically, we will work on the archaeal and eukaryotic MCM proteins, an essential set of eukaryotic RuvB-like proteins (Rvb1p/Rvb2p), and a RecA-like circadian clock protein (KaiC)

描述（由申请人提供）：同源遗传重组部分是由于人群中引入遗传多样性的原因。在许多不同的压力和挑战下，这种多样性对于该人群的长期生存能力至关重要。现在，同源遗传重组也被广泛接受为个体内DNA修复的一种机制之一，重组/修复途径的缺陷已与遗传不稳定性和癌症相关。细菌RECA蛋白一直是理解同源遗传重组的主要模型系统之一，我们知道人Rad51和DMC1蛋白是RECA的结构同源物，分别在DNA修复和减数分裂中起关键作用。但是，我们详细了解这些蛋白质实际上在催化不同分子和链交换中同源性识别的方式中起作用非常有限，部分原因是我们只有高分辨率的组件结构，而对于功能组件的低分辨率结构。我们将通过应用于研究螺旋聚合物开发的独特图像处理方法的应用，极大地扩展我们对RECA和RAD51丝的现有电子显微镜研究。我们有能力查看这些蛋白在DNA上形成的复合物，而这种复合物不能通过晶体学或NMR直接研究。我们还将使用电子显微镜和图像分析来研究环形酶和分支迁移泵等环形复合物，这些泵在DNA复制，重组和修复的许多领域起作用。具体而言，我们将研究古细菌和真核MCM蛋白，这是一组必不可少的真核RUVB样蛋白（RVB1P/RVB2P），以及一个类似RecA的昼夜节律钟表蛋白（KAIC）