STRUCTURE & FUNCTION OF NON-WATSON-CRICK TELOMERIC DNA

结构

• 批准号: 3467350
• 负责人: Eric R HENDERSON
• 金额: $ 9.03万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3467350
• 关键词: DNA; DNA binding protein; Tetrahymena; X ray crystallography; cell cycle; electron microscopy; fluorescence microscopy; laboratory mouse; microinjections; monoclonal antibody; nuclear magnetic resonance spectroscopy; nucleic acid sequence; nucleic acid structure; protein structure function

Chromosome stability is crucial for the faithful passage of genetic information at each cell division. Telomeres are structures at chromosomal termini that are essential for chromosome stability. All telomeric DNA contains simple, G/C-rich, repeated sequences in which the G and C residues are segregated to opposite strands of the duplex. The G-rich strand of all telomeres examined extends beyond the duplex at the molecular terminus of the telomere. In vitro, all telomeric G-rich strands tested can self-associate by non-Watson-Crick (G-G and G-T) base pairing. Taken together, these data suggest that the G-strand overhang forms a self-associated structure in vivo and that this structure is intimately involved in telomere function. The goal of this project is to understand how telomeres confer stability to chromosomes and, more specifically, what the role(s) of the unique G- strand DNA structure is (are) in accomplishing this. The specific aims are: 1) to determine the molecular details of the G-strand structure, 2) to ascertain the biological function of the telomeric G-strand structure using in vitro and in vivo assays and to determine if non-Watson-Crick base paired structures can form in a Watson-Crick Environment, 3) to characterize an activity we have identified that binds specifically to the G-strand structure, 4) to produce monoclonal antibodies that react with the G-strand structure and 5) to explore telomere location and dynamics in fixed and living cells by fluorescence and electron microscopy.

染色体稳定性是遗传基因忠实传递的关键 每一次细胞分裂的信息。端粒是一种结构 对染色体稳定性至关重要的染色体末端。全 端粒DNA包含简单的，富含G/C的重复序列，其中 G和C残基被分离到双链的相反链上。这个 所检测的所有端粒的富含G的链延伸到双链以外的 端粒的分子末端。在体外，所有端粒富含G 被测试的链可以通过非Watson-Crick(G-G和G-T)碱基自关联 配对。综上所述，这些数据表明G链悬垂 在体内形成一种自相关结构，这种结构是 与端粒功能密切相关。 这个项目的目标是了解端粒如何赋予稳定性。 染色体，更具体地说，独一无二的G-G- 链DNA结构是实现这一点的关键。具体目标 是：1)确定G-链结构的分子细节，2) 确定端粒G链结构的生物学功能 使用体外和体内试验并确定非沃森-克里克 碱基配对结构可以在Watson-Crick环境中形成，3)到 描述我们确定的特定绑定到的活动的特征 G链结构，4)产生产生反应的单抗 利用G链结构和5)探索端粒定位和 固定细胞和活细胞的荧光和电子动力学 显微镜。