CELL CYCLE REGULATION OF EUKARYOTIC DNA REPLICATION

真核 DNA 复制的细胞周期调控

• 批准号: 6636328
• 负责人: JOACHIM J LI
• 金额: $ 27.82万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6636328
• 关键词: DNA replication; DNA replication origin; Saccharomyces cerevisiae; cell cycle; cyclin dependent kinase; protein protein interaction

DESCRIPTION: The investigator's long-term goal is to understand how DNA replication is regulated during the eukaryotic cell cycle. A central question about this regulation is how replication origins are prevented from re-initiating DNA replication within a single cell cycle. Strict enforcement of this block at the hundreds to thousands of origins in an eukaryotic genome is required for the faithful propagation and stable transmission of genetic information. Loss of this control could contribute to the genomic instability associated with tumorigenesis. The investigator is studying the block to re-initiation in the budding yeast Saccharomyces cerevisiae, where combined genetic and biochemical analysts have identified many of the molecular components involved in regulating the cell cycle and initiating DNA replication. Work from their lab and that of others has shown that cyclin dependent kinases (CDKs; particularly Clb/Cdc28 in budding yeast) play a pivotal role in preventing re-initiation. In this proposal, he wishes to identify the critical targets of these kinases and determine how phosphorylation of these targets inhibits re-initiation. The investigator's preliminary studies raise the possibility that Clb kinases use multiple overlapping mechanisms to target three components of the initiation complex: the origin recognition complex (ORC); Cdc6; and the Mcm2-7 family of proteins. To test this hypothesis he will: (1) Determine whether simultaneous deregulation of these three initiation components leads to re-initiation of DNA replication; (2) Determine whether ORC and Mcm proteins are substrates of Clb kinases in vivo ; (3) Investigate the molecular mechanisms underlying the block to re-initiation; and (4) Test additional mechanisms that may contribute to the block to re-initiation. Because the components of the initiation machinery are conserved among eukaryotes, he anticipates that an understanding of how this machinery is regulated during the budding yeast cell cycle will serve as a paradigm for understanding this regulation in other eukaryotes.

描述：研究者的长期目标是了解DNA 在真核细胞周期中调节复制。一个核心问题 关于该法规是如何防止复制起源的 在单个细胞周期内重新生产DNA复制。严格执行 在真核基因组中，这个数百至数千个起源是 忠实传播和遗传稳定传播所必需的 信息。失去这种控制可能导致基因组不稳定性 与肿瘤发生有关。研究人员正在研究街区 在酿酒酵母的萌芽酵母糖果疗法中的重新生产，合并 遗传和生化分析师已经确定了许多分子 调节细胞周期和启动DNA的组件 复制。从他们的实验室和其他实验室的工作表明细胞周期蛋白 依赖性激酶（CDK；特别是在发芽酵母中的CLB/CDC28）玩 关键作用在防止重新启动中。在这个建议中，他希望 确定这些激酶的关键靶标，并确定如何 这些靶标的磷酸化抑制了重新生产。调查员的 初步研究提出了CLB激酶使用多种的可能性 重叠的机制以针对启动复合物的三个组成部分： 起源识别综合体（ORC）； cdc6;和MCM2-7蛋白质家族。 为了检验这一假设，他将：（1）确定是否同时 放松这三个起始组件导致DNA的重新生成 复制； （2）确定ORC和MCM蛋白是否是CLB的底物 体内激酶； （3）研究块的分子机制 重新启动； （4）测试可能有助的其他机制 重新启动。因为启动机械的组件是 他在真核生物中保守，他预计对这一方式的理解 在萌芽的酵母细胞周期中调节机械将作为一个 理解其他真核生物中这种调节的范式。