Replication Initiation in Bacteria and Eukaryotes

细菌和真核生物中的复制起始

• 批准号: 7917135
• 负责人: David Jeruzalmi
• 金额: $ 27.62万
• 依托单位: HARVARD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-18 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7917135
• 关键词: Address; Antibiotics; Antineoplastic Agents; Architecture; Area; Bacillus cereus; Bacteria; Bacteriophages; Binding; Binding Sites; Biological Assay; Cell Cycle; Cells; Chromosomes; Collection; Complex; DNA; DNA Binding; DNA Primase; DNA biosynthesis; DNA replication origin; Data; Deposition; Development; DnaB helicase; Drug Design; Elements; Ensure; Escherichia coli; Eukaryota; Foundations; Genome; Goals; Human; Length; Maintenance; Malignant Neoplasms; Measures; Modeling; Molecular Target; Nucleotides; Pathway interactions; Positioning Attribute; Proteins; Recruitment Activity; Regulation; Replication Initiation; Research; Roentgen Rays; Sampling; Science; Shapes; Signal Transduction; Site; Structure; Work; X-Ray Crystallography; base; design; helicase; macromolecular assembly; novel; novel therapeutics; origin recognition complex; protein complex; public health relevance; research study; success

DESCRIPTION (provided by applicant): The goal of this work is a structure-based understanding of how DNA replication is initiated. Replication initiates at multiple sites on the genome called origins of DNA replication. Specialized protein complexes bind at these sites and prepare the duplex for replication. The activity of these ensembles is tightly controlled to ensure that only one copy of the genome is made per cell cycle. The architecture, regulation and mechanisms of action of these large complexes are incompletely understood. Our work is of practical significance because regulatory changes in origin complexes contribute to human cancers. Efforts with bacterial complexes will provide much needed targets for development of novel antibiotics. We study replication initiation complexes in eukaryotes and bacteria. A large body of work has described components of origin complexes and details of how they operate. What is missing, however, in any of these cases, is a three-dimensional view of the initiation machine to guide our understanding of how these components work together. The overall goal of our research is to provide such views. The current proposal incorporates three complementary approaches that focus on several components involved in origin recognition and DNA unwinding. Aim #1 is directed at several bacterial helicaseloader complexes, whose structure and function can be dissected at a sophisticated level and will inform our understanding of eukaryotic complexes. Aim #2 is addressed at obtaining and analyzing the complete ORC ensemble. Aim #3 exploits our recent identification of a unique bacterial MCM complex, which is more tractable, but should still provide a faithful model for its eukaryotic counterparts. PUBLIC HEALTH RELEVANCE Cells prepare for the next round of DNA replication by depositing macromolecular assemblies onto sites on the genome termed origins of DNA replication. Emerging evidence suggests that these DNA replication initiation assemblies represent a rich collection of molecular targets against which to design novel therapeutics. This pathway is not well represented in efforts to discover anti-cancer agents. Lack of useful structural information on relevant molecular targets has stymied efforts at structure-guided drug design. Our structure determination efforts will advance efforts to discover novel anti-cancer agents. Also, our work with bacterial complexes will provide much needed targets for development of novel antibiotics.

描述（由申请人提供）：这项工作的目标是基于结构的理解 DNA 复制是如何启动的。复制起始于基因组上的多个位点，称为 DNA 复制起点。特殊的蛋白质复合物结合在这些位点并准备双链体以进行复制。这些基因组的活动受到严格控制，以确保每个细胞周期仅生成一份基因组副本。这些大型复合物的结构、调节和作用机制尚不完全清楚。我们的工作具有实际意义，因为起源复合物的调控变化会导致人类癌症。对细菌复合物的研究将为新型抗生素的开发提供急需的目标。我们研究真核生物和细菌中的复制起始复合物。大量的工作描述了起源复合物的组成部分以及它们如何运作的细节。然而，在任何这些情况下，都缺少启动机的三维视图来指导我们理解这些组件如何协同工作。我们研究的总体目标就是提供这样的观点。目前的提案采用了三种互补的方法，重点关注涉及起源识别和 DNA 解旋的几个组成部分。目标#1针对几种细菌解旋酶装载复合物，其结构和功能可以在复杂的水平上进行剖析，并将有助于我们对真核复合物的理解。目标#2 旨在获取并分析完整的 ORC 整体。目标 #3 利用了我们最近鉴定的一种独特的细菌 MCM 复合物，该复合物更容易处理，但仍应为其真核对应物提供忠实的模型。公共卫生相关性 细胞通过将大分子组装体沉积到基因组上称为 DNA 复制起点的位点，为下一轮 DNA 复制做好准备。新出现的证据表明，这些 DNA 复制起始组件代表了丰富的分子靶标集合，可根据这些靶标设计新颖的疗法。该途径在发现抗癌药物的努力中没有得到很好的体现。缺乏相关分子靶点的有用结构信息阻碍了结构引导药物设计的努力。我们的结构测定工作将推动新型抗癌药物的发现。此外，我们对细菌复合物的研究将为新型抗生素的开发提供急需的目标。