STRUCTURAL STUDIES OF DNA REPAIR PROTEINS

DNA 修复蛋白的结构研究

• 批准号: 8361613
• 负责人: NIKOLA P PAVLETICH
• 金额: $ 6.4万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8361613
• 关键词: Alleles; Biochemical; Caenorhabditis elegans; Cell division; Cells; Coupling; DNA Double Strand Break; DNA biosynthesis; DNA repair protein; Development; Embryo; Fission Yeast; Funding; Grant; Human; Hypersensitivity; KRP protein; Knockout Mice; Length; Longevity; Modeling; Mus; National Center for Research Resources; Nematoda; Organism; Orthologous Gene; Phenotype; Phosphotransferases; Physiological Processes; Principal Investigator; Protein Kinase; Proteins; Reporting; Reproduction; Research; Research Infrastructure; Resources; Role; Saccharomyces cerevisiae; Source; Stress; United States National Institutes of Health; Yeasts; cost; structural biology; telomere

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Tel2 is a well-conserved protein that is essential for yeast viability. Determining the precise role of Tel2 has been complicated by its many apparently nonoverlapping functions reported in various organisms. In addition to maintaining telomere length in S. cerevisiae, it functions in the DNA replication checkpoint in the fission yeast Schizosaccharomyces pombe and in humans, coupling the onset of cell division with the successful replication of DNA. In the nematode Caenorhabditis elegans, however, hypomorphic alleles (forms of agene in which the encoded protein has reduced function compared with the wild type allele) of clk-2/rad-5 (the TEL2 ortholog in C. elegans) not only can cause stress during DNA replication and hypersensitivity to DNA double-strand breaks, but also can increase life span and reduce the rate of numerous physiological processes, including embryonic and postembryonic development, and reproduction. Through systematic analysis of the phenotype of Tel2-null mouse cells and biochemical protein interaction studies, it was determined that TEL2 directly interacts with all six of the mammalian phosphatidylinositol3-kinaserelated protein kinases (PIKKs). Absence of TEL2 substantially reduced the expression level of all PIKKs in mouse cells, impinging on their function. Because a direct physical association between Tel2 and PIKKs was also recently observed in fission yeast, the function of Tel2 as a stabilizer of these kinases may also be conserved. These results provide a unifying model for all the reported functions of mammalian Tel2 and its orthologs.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的首席研究员可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 Tel2 是一种保存完好的蛋白质，对于酵母的生存至关重要。由于 Tel2 在各种生物体中报告的许多明显不重叠的功能，确定 Tel2 的精确作用变得很复杂。除了维持酿酒酵母中的端粒长度外，它还在裂殖酵母粟酒裂殖酵母和人类的 DNA 复制检查点中发挥作用，将细胞分裂的开始与 DNA 的成功复制结合起来。然而，在线虫秀丽隐杆线虫中，clk-2/rad-5（秀丽隐杆线虫中的 TEL2 直系同源物）的亚等位基因（其中编码的蛋白质与野生型等位基因相比功能降低的基因形式）不仅会导致DNA 复制过程中的应激和对 DNA 双链断裂的过敏，而且还可以延长寿命并降低许多生理过程的速率，包括胚胎和胚胎后发育、繁殖。通过对 Tel2-null 小鼠细胞表型的系统分析和生化蛋白质相互作用研究，确定 TEL2 直接与所有六种哺乳动物磷脂酰肌醇 3 激酶相关蛋白激酶 (PIKK) 相互作用。 TEL2 的缺失大大降低了小鼠细胞中所有 PIKK 的表达水平，影响了它们的功能。由于最近在裂殖酵母中也观察到 Tel2 和 PIKK 之间的直接物理关联，因此 Tel2 作为这些激酶稳定剂的功能也可能得到保留。这些结果为哺乳动物 Tel2 及其直向同源物的所有已报道功能提供了统一模型。