Understanding the Physical Mechanism of Telomere End Capping

了解端粒封端的物理机制

• 批准号: 0617956
• 负责人: Deborah Wuttke
• 金额: $ 62.9万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0617956&HistoricalAwards=false
• 关键词: Understanding; Physical; Mechanism; Telomere; End

Proper capping of telomeres is critical for maintaining chromosomal integrity by preventing degradation, recombination, end-to-end fusions and recognition by DNA damage checkpoints. The absence of telomere capping leads to catastrophic chromosomal damage. While the proteins that participate in these functions in vivo have been identified, scant information on their function in vitro is available. Biochemical and structural data are needed to develop viable mechanistic models for telomere function. The objective of this research program is to obtain detailed biochemical and structural data to determine the mechanism of telomere capping. The proteins comprising the S. cerevisiae chromosomal end cap have been genetically defined as Cdc13, Stn1 and Ten1. The principal investigator will determine the physical basis for capping activity mediated by these proteins. Protein/protein and protein/nucleic acid interactions will be measured to develop a complete biochemical understanding of the telomere end-protection complex. NMR will be used to map intermolecular interfaces of the end-capping complexes. Insights into the mechanism of end protection will be obtained by mutagenesis of these interfaces in vitro and in vivo. Furthermore, the investigator will study telomerase activity in the presence and absence of capping components. This hypothesis-driven research program will, through a series of focused and prioritized objectives, provide significant biochemical and structural insights into the mechanism of capping complex formation.Completion of this program will lead to important mechanistic understanding of telomere maintenance, an essential process in eukaryotic cells. The program will also make extensive use of multi-institutional high-field NMR facilities, providing both an excellent training opportunity for program participants as well as supporting the scientific infrastructure. In addition, the program will increase training opportunities for groups under-represented in science. The PI will continue mentoring activities for students, postdoctoral fellows and young faculty from under-represented groups, and will target undergraduate institutions with minority populations for outreach.

端粒的正确加帽对于通过防止降解、重组、端到端融合和 DNA 损伤检查点识别来维持染色体完整性至关重要。 端粒加帽的缺失会导致灾难性的染色体损伤。 虽然体内参与这些功能的蛋白质已被鉴定，但有关其体外功能的信息却很少。 需要生化和结构数据来开发可行的端粒功能机制模型。该研究计划的目的是获得详细的生化和结构数据，以确定端粒加帽的机制。 构成酿酒酵母染色体端帽的蛋白质在遗传学上被定义为 Cdc13、Stn1 和 Ten1。 主要研究人员将确定这些蛋白质介导的加帽活性的物理基础。 将测量蛋白质/蛋白质和蛋白质/核酸相互作用，以形成对端粒末端保护复合物的完整生化理解。 NMR 将用于绘制封端复合物的分子间界面图。 通过体外和体内这些界面的诱变可以获得对末端保护机制的深入了解。 此外，研究人员将研究存在和不存在加帽成分时的端粒酶活性。这个以假设为驱动的研究计划将通过一系列重点突出和优先考虑的目标，为封端复合物形成的机制提供重要的生化和结构见解。该计划的完成将带来对端粒维持（真核细胞中的一个重要过程）的重要机制的理解。 该计划还将广泛使用多机构高场核磁共振设施，为计划参与者提供极好的培训机会并支持科学基础设施。 此外，该计划还将增加科学领域代表性不足的群体的培训机会。 PI 将继续为来自弱势群体的学生、博士后研究员和年轻教师开展指导活动，并将针对少数民族人口的本科院校进行推广。