Analysis of telomerase reverse transcriptase

端粒酶逆转录酶分析

• 批准号: 7939112
• 负责人: NEAL F LUE
• 金额: $ 24.55万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7939112
• 关键词: Apoptosis; Architecture; Binding; Biochemical Genetics; Biological; Biological Assay; Biological Models; Biology; Cells; Chromatin Remodeling Factor; Collection; Complex; DNA; Data; Development; Electrostatics; Enzymatic Biochemistry; Enzymes; Funding; Goals; Human; In Vitro; Maps; Mediating; Modeling; Mutagenesis; Mutation; Names; Neoplastic Cell Transformation; Nucleic Acids; Primer Extension; Proteins; Proteolysis; RNA; RNA Binding; RNA Recognition Motif; RNA-Protein Interaction; Regulation; Research; Research Personnel; Ribonucleoproteins; Role; Saccharomyces cerevisiae; Saccharomycetales; Sequence Alignment; Series; Site; Structure; Surface; Telomerase; Telomere Maintenance; Telomere Shortening; Terminal Repeat Sequences; Tertiary Protein Structure; Testing; Yeasts; base; cancer cell; cancer therapy; clinical application; crosslink; genetic regulatory protein; in vitro activity; in vivo; insight; mutant; neoplastic cell; novel; programs; telomerase reverse transcriptase; telomere

DESCRIPTION (provided by applicant): Telomerase is a ribonucleoprotein complex responsible for replenishing the G-rich strand of the telomere terminal repeats. It employs a small, embedded segment of a stably associated RNA component as template, and pre-existing chromosomal ends as primers to synthesize telomere tracts. Telomerase activity is specifically activated in cancer cells, and promotes neoplastic transformation by endowing cells with unlimited replicative potential. Inhibition or depletion of telomerase in tumor cells leads to telomere shortening and apoptosis, validating the potential of anti-telomerase strategies in cancer therapy. The goal of this research is to understand telomerase mechanisms and regulation using the budding yeast Saccharomyces cerevisiae as a model system. Our studies during the past funding period have yielded a wealth of information on the structure and functions of the catalytic TERT protein. In addition, they revealed (i) two telomerase-specific domains within the catalytic TERT subunit that are responsible for a unique feature of telomerase enzymology, i.e., the ability to repetitively copy a short RNA template; (ii) an alpha-helical repeat domain (named TPR) in the Est1 p subunit that possesses a novel RNA-binding activity, and (iii) regulation of telomere structure and function by an ATP-dependent chromatin remodeling complex (the INO80 complex). Based on these findings, we propose a series of biochemical, genetic and cell biological studies directed toward (1) clarifying the mechanisms and biological significance of the protein- DNA and protein-RNA interactions mediated by telomerase components, and (2) ascertaining the roles of chromatin remodeling complexes in modulating telomere structures and telomerase activity. Results from the proposed studies are expected to broaden and deepen current understandings of telomerase mechanisms and provide insights into a novel aspect of telomere regulation. Because almost all of the factors that will be examined are conserved between yeast and humans, we anticipate that many of the findings will be applicable to human telomeres and telomerase, and will facilitate the development of clinical applications based on telomere biology.

描述（由申请人提供）：端粒酶是一种核糖核蛋白复合物，负责补充端粒末端重复序列的富含G链。它采用稳定关联的 RNA 成分的一小段嵌入片段作为模板，并使用预先存在的染色体末端作为引物来合成端粒束。端粒酶活性在癌细胞中被特异性激活，并通过赋予细胞无限的复制潜力来促进肿瘤转化。肿瘤细胞中端粒酶的抑制或消耗会导致端粒缩短和细胞凋亡，验证了抗端粒酶策略在癌症治疗中的潜力。这项研究的目标是使用芽殖酵母酿酒酵母作为模型系统来了解端粒酶机制和调节。我们在过去的资助期间的研究已经获得了大量关于催化 TERT 蛋白的结构和功能的信息。此外，他们还揭示了（i）催化 TERT 亚基内的两个端粒酶特异性结构域，它们负责端粒酶酶学的独特特征，即重复复制短 RNA 模板的能力； (ii) Est1 p 亚基中的 α 螺旋重复结构域（称为 TPR）具有新颖的 RNA 结合活性，以及​​ (iii) 通过 ATP 依赖性染色质重塑复合物（INO80 复合物）调节端粒结构和功能。基于这些发现，我们提出了一系列生化、遗传和细胞生物学研究，旨在 (1) 阐明端粒酶成分介导的蛋白质-DNA 和蛋白质-RNA 相互作用的机制和生物学意义，以及 (2) 确定其作用染色质重塑复合物在调节端粒结构和端粒酶活性中的作用。拟议研究的结果预计将扩大和加深当前对端粒酶机制的理解，并为端粒调节的新方面提供见解。由于几乎所有要检查的因素在酵母和人类之间都是保守的，因此我们预计许多发现将适用于人类端粒和端粒酶，并将促进基于端粒生物学的临床应用的开发。