Molecular Mechanisms of Telomere Length Homeostasis

端粒长度稳态的分子机制

• 批准号: 8463219
• 负责人: Feng Qiao
• 金额: $ 27.92万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8463219
• 关键词: Aging; Binding; Binding Proteins; Biochemical; Biochemistry; Biological Models; C-terminal; Cell Proliferation; Chromosomes; Competence; Complex; Cryoelectron Microscopy; DNA; DNA Damage; DNA Repair; Data; Degenerative Disorder; Development; Disease; Dissection; Double-Stranded Telomeric Binding Protein; Ensure; Fission Yeast; Foundations; Functional disorder; Genetic; Genome; Goals; Homeostasis; Human; Hybrids; In Vitro; Lead; Length; Link; Malignant Neoplasms; Maps; Mediating; Modeling; Molecular; Mutation; N-terminal; Nucleoproteins; Point Mutation; Premature aging syndrome; Process; Proteins; Regulation; Research; Role; SS DNA BP; Signal Transduction; Site; Solid; Structure; Structure-Activity Relationship; Telomerase; Testing; Therapeutic; Two-Hybrid System Techniques; Work; X-Ray Crystallography; Yeasts; base; cancer cell; design; in vivo; insight; member; mutant; novel; novel therapeutic intervention; particle; protein complex; protein protein interaction; reconstruction; stem cell differentiation; structural biology; telomere; tool; yeast genetics

DESCRIPTION (provided by applicant): The long-term goal of this proposal is to understand, in detail, the molecular mechanisms of telomere homeostasis through comprehensive characterization of the telomere protein-DNA complex. Telomeres ensure genome integrity by facilitating chromosome end replication through telomerase. In addition, telomeres also protect the chromosome ends from DNA repair and degradation activities. Mutations in telomerase subunits or telomere components have been linked to premature aging and cancer. Maintaining proper telomere structure and length is required for accomplishing both its chromosome end replication and end protection tasks. The structure-function relationship of this complex is a central question in understanding the mechanisms of telomere homeostasis. We will exploit the genetically amendable S. pombe model system and employ a combination of biochemical, structural and genetic tools to achieve the following specific aims: 1. Map the respective protein-protein interaction interfaces between Tpz1 and its interaction partners and examine the dynamics of the Tpz1-centered complex formation in vitro. 2. Reveal the functional roles of Tpz1 mediated interactions in telomere length homeostasis and chromosome end protection. 3. Achieve a comprehensive structural analysis of the Tpz1-centered complex using single particle cryo-electron microscopy (cryo-EM) and X-ray crystallography. Accomplishment of the proposed aims will provide new and significant mechanistic insights into the structure-function relationship and the dynamics of the telomere complex, and may also provide the foundation for development of new therapeutic approaches against diseases caused by telomere dysfunction.

描述(由申请人提供)：这项建议的长期目标是通过对端粒蛋白-DNA复合体的全面表征来详细了解端粒稳态的分子机制。端粒通过端粒酶促进染色体末端复制，从而确保基因组的完整性。此外，端粒还保护染色体末端不受DNA修复和降解活动的影响。端粒酶亚基或端粒成分的突变与过早衰老和癌症有关。保持适当的端粒结构和长度是完成染色体末端复制和末端保护任务所必需的。该复合体的结构-功能关系是理解端粒稳态机制的核心问题。我们将开发可遗传修饰的S.pombe模型系统，并结合生化、结构和遗传学工具来实现以下特定目标：1.绘制Tpz1与其相互作用伙伴之间的蛋白质-蛋白质相互作用界面，并研究以Tpz1为中心的复合体在体外的形成动力学。2.揭示Tpz1介导的相互作用在端粒长度稳态和染色体末端保护中的功能作用。3.利用单粒子低温电子显微镜(Cryo-EM)和X射线结晶学对Tpz1中心配合物进行了全面的结构分析。这些目标的实现将为端粒复合体的结构-功能关系和动力学提供新的和重要的机制见解，并可能为开发治疗端粒功能障碍引起的疾病的新的治疗方法提供基础。