Structure of ribonucleoprotein: telomerase

核糖核蛋白的结构：端粒酶

• 批准号: 6777715
• 负责人: Gabriele Varani
• 金额: $ 29.74万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-09 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6777715
• 关键词: RNA; RNA directed DNA polymerase; X ray crystallography; conformation; enzyme activity; enzyme complex; enzyme mechanism; enzyme structure; fungal proteins; intermolecular interaction; molecular assembly /self assembly; nuclear magnetic resonance spectroscopy; posttranscriptional RNA processing; protein protein interaction; protein purification; protein quantitation /detection; protein structure function; ribonucleoproteins; telomerase; telomere; yeasts

DESCRIPTION (provided by applicant): The goal of this proposal is to study the structure/function relationship of telomerase. This enzyme protects the ends of chromosomes, maintains their length during cellular division, and is selectively activated in most humans cancers. Through these activities, it maintains genomic integrity, promotes cellular immortalization, and sustains the proliferating status of transformed cells: its pharmacological inhibition may very well provide a new avenue to cancer treatment. Telomerase is a ribonucleoprotein composed of a non-coding RNA, a protein enzymatic component and additional essential protein subunits. Very little is known structurally on telomerase or its components, yet this knowledge, and an understanding of the molecular interactions between its protein and RNA components, are essential to understand its function and mechanism. We propose to determine the structure of telomerase-associated proteins and of key functional domains of its RNA component. The structural information will be integrated into a biochemical and functional context, through collaborations with biochemists and molecular biologists (Gottchling, Lingner and Rhodes), who will provide the breadth of expertise required to answer, at the molecular level, fundamental questions on how this enzyme functions. The enzymatic activity of telomerase (TERT) is homologous to viral reverse transcriptases, while the RNA (TER) provides the template and a landing dock for RNP assembly. Different biochemical functions map to specific domains of TER and to the proteins that associate with them. Because the telomerase holoenzyme is large and complex, I propose to build up its structure from its constituent parts, based on the "divide-and-conquer" principle. Specifically, I propose to study protein-RNA complexes responsible for: 1. RNA processing, stability and assembly of the mature RNP; 2. Targeting of the mature telomerase to the telomeres; 3. Binding and activation of TERT. The research plan will be based on: 1. The analysis by NMR of the structure and dynamics of the domains of TER responsible for each of these functions; 2. The determination of the structure of the proteins that interact with such domains; 3. The biochemical and structural characterization of the resulting RNA-protein complexes; 4. The design and execution of new biochemical and functional experiments, grounded onto the structural results, that will address the biological function of these protein-RNA complexes.

描述（由申请人提供）：该提案的目的是研究端粒酶的结构/功能关系。这种酶可以保护染色体的末端，在细胞分裂期间保持其长度，并在大多数人类癌症中有选择地激活。通过这些活动，它保持基因组完整性，促进细胞永生化并维持转化细胞的增殖状态：其药理抑制作用很可能为癌症治疗提供了新的途径。端粒酶是由非编码RNA，蛋白质成分和其他必需蛋白质亚基组成的核糖核蛋白。在端粒酶或其成分上的结构上很少知道，但是这种知识以及对其蛋白质与RNA成分之间的分子相互作用的理解对于了解其功能和机制至关重要。我们建议确定端粒酶相关蛋白的结构以及其RNA成分的关键功能结构域的结构。 结构信息将通过与生物化学家和分子生物学家（Gottchling，Lingner和Rhodes）的合作融入生化和功能性背景中，后者将在分子水平上提供有关这种酶的基本问题所需的专业知识。 端粒酶（TERT）的酶活性与病毒逆转录酶同源，而RNA（TER）为RNP组装提供了模板和降落码头。不同的生化功能映射到TER的特定域和与之相关的蛋白质。由于端粒酶全酶很大而复杂，因此我建议根据“分裂和构成”原则从其组成部分建立其结构。具体而言，我建议研究负责：1。成熟RNP的RNA处理，稳定性和组装的蛋白质RNA复合物； 2。将成熟的端粒酶靶向端粒； 3。tert的结合和激活。研究计划将基于：1。NMR分析了负责这些功能的TER领域的结构和动力学； 2。确定与此类结构域相互作用的蛋白质的结构； 3。所得RNA-蛋白复合物的生化和结构表征； 4。建立在结构结果上的新生化和功能实验的设计和执行将解决这些蛋白-RNA复合物的生物学功能。