CONTROL OF DNA REPLICATION AND CELL DIVISION

DNA 复制和细胞分裂的控制

• 批准号: 6610934
• 负责人: TERESA S WANG
• 金额: $ 5.71万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6610934
• 关键词: DNA directed DNA polymerase; DNA replication; Saccharomyces; cell cycle; cell growth regulation; fungal genetics; gene expression; immunoprecipitation; laboratory rabbit; nucleic acid sequence; polymerase chain reaction; proliferating cell nuclear antigen

The long-term goal of this research program is to investigate how a cell gauges the status of DNA replication to maintain the temporal order of the cell cycle. In a normal cell cycle, entry into mitosis is dependent upon the completion of S phase and this dependency is maintained by a control mechanism termed checkpoint control. Genetic studies of yeast have suggested that once cells exit G1 and pass START, cells are committed to enter both S phase and mitosis. The presence of a replication complex signals the cell that it is in S phase and restrains the cell from entering mitosis prematurely; subsequent disassembly of the replication complex then activates the onset of mitosis. We propose to use fission yeast as a model organism and DNA polymerases alpha and delta and PCNA as probes to investigate what gene products generate a signal or sense and transmit a signal to restrain cells from entering mitosis when initiation or replication is faltered due to defects in one of these replication enzymes or protein. The specific aims are: (I) Characterize a panel of mutants that fail to restrain cells from premature mitotic entry when S-phase progression is delayed due to a semi-disabled DNA polymerase delta. (II) Identify genes that detect the initiation defects caused by a semi-disabled DNA polymerase alpha to prevent cells from premature mitotic entry. (III) Identify alleles of PCNA that are involved in S phase progression, and isolate and characterize gene products that interact with these alleles. These studies will provide a foundation for further understanding of cell cycle checkpoint mechanisms. Knowledge gained from the fission yeast studies can be applied to human cells in the future, and thus will contribute to the basic understanding of the molecular etiology of neoplasia.

这项研究计划的长期目标是调查 细胞测量DNA复制的状态以维持暂时的 细胞周期的顺序。在正常的细胞周期中，进入有丝分裂是 依赖于S阶段的完成，而这种依赖是 由一种称为检查点控制的控制机制维护。 酵母的遗传学研究表明，一旦细胞退出G1和 通过启动，细胞致力于进入S期和有丝分裂。 复制复合体的存在向细胞发出信号，表明它在S体内 时相，抑制细胞过早进入有丝分裂； 随后对复制复合体的拆解激活了 开始有丝分裂。我们建议使用分裂酵母作为模式生物 DNA聚合酶α、β和增殖细胞核抗原作为探针 调查哪些基因产物产生信号或感觉并传递 抑制细胞在启动或分裂时进入有丝分裂的信号 由于其中一个复制中的缺陷，复制失败 酶或蛋白质。具体目标是：(I)确定小组的特征 在以下情况下未能抑制细胞过早进入有丝分裂的突变 S期进展因dna半失活而延迟 聚合酶三角洲。(Ii)确定检测到启动缺陷的基因 由半失活的DNA聚合酶α引起，以防止细胞 来自过早的有丝分裂进入。(Iii)确定增殖细胞核抗原的等位基因 参与S期进展的基因的分离和鉴定 与这些等位基因相互作用的产物。 这些研究将为进一步了解 细胞周期检查点机制。从核裂变中获得的知识 酵母菌研究未来可以应用于人类细胞，因此将 有助于对血吸虫病分子病因学的基本理解 肿瘤。