Role of the Werner syndrome protein complex in the metabolism of chromosome ends

维尔纳综合征蛋白复合物在染色体末端代谢中的作用

基本信息

批准号：
7888108
负责人：
LUCIO COMAI
金额：
$ 38.01万
依托单位：
UNIVERSITY OF SOUTHERN CALIFORNIA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-01 至 2015-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7888108
关键词：
Affect Age Age of Onset Aging Apoptosis Arabidopsis Biochemical Biochemical Genetics Biological Assay Cardiovascular Diseases Cell Aging Cell physiology Cells Chromosomes Complex DNA DNA Binding Domain DNA Damage DNA Structure Data Development Disease Disease Progression Dominant-Negative Mutation Employee Strikes Enzymes Excision Exonuclease Family member Fibroblasts Foundations G22P1 gene General Population Genes Genetic Genetic Recombination Genome Genomic Instability Goals Hereditary Disease Homeostasis Human In Vitro Incidence Length Link Longevity Maintenance Malignant Neoplasms Measures Mediating Metabolism Modeling Molecular Molecular Conformation Names Nature Normal Cell Nuclear Protein Nuclear Proteins Nucleic Acids Pathology Pathway interactions Patients Phenotype Physiological Plants Play Premature aging syndrome Process Production Property Protein Binding Proteins Regulation Residual state Role Signal Transduction Southern Blotting Telomerase Telomere Maintenance Telomere Shortening Testing Therapeutic Agents TimeLine Treatment Effectiveness Two-Dimensional Gel Electrophoresis Werner Syndrome Work XRCC3 gene base chromatin immunoprecipitation early onset extrachromosomal DNA helicase homologous recombination human WRN protein improved in vivo insight loss of function mutation malignant phenotype member mutant overexpression premature prevent protein complex protein function protein protein interaction public health relevance reconstitution repaired research study response senescence telomere therapeutic development

项目摘要

DESCRIPTION (provided by applicant): The goal of this study is to gain mechanistic insights on the function of the Werner syndrome protein (WRN) complex in the processes that maintain telomere integrity and prevent the formation of extrachromosomal telomeric circles. WRN is a nuclear protein with helicase and exonuclease activities, whose loss-of-function mutations are associated with the premature aging and cancer prone disease Werner syndrome (WS). Genetic and biochemical evidence implicate WRN in telomere metabolism and suggest that abnormal telomere length homeostasis contributes to the pathology of WS. Our biochemical studies have shown that WRN operates as a functional unit with the Ku70/80 heterodimer and have further demonstrated that loss of WRN function causes the production of telomeric circles in fibroblasts expressing telomerase. To determine the mechanism whereby the WRN complex regulates telomere homeostasis, we propose to mechanistically characterize the functional interplay between WRN, Ku and telomere-specific factors found at chromosome ends and define the process activated by loss of WRN function responsible for the formation of telomeric circles. To accomplish these objectives we propose the following three aims. In Aim 1, we will characterize the role of WRN and its interacting partner Ku70/80 in the regulation of telomeric termini in human cells. In Aim 2, we will dissect the molecular mechanisms leading to the formation of extrachromosomal t- circles resulting from loss of WRN function. In Aim 3, we will characterize the biochemical properties of WRN in the context of model telomeric substrates in vitro. The studies proposed in this application will elucidate the role of WRN at telomeres and provide valuable information for understanding how loss of WRN function promotes genome instability, premature aging and the early onset of diseases such as cancer and cardiovascular disease. It is recognized that the incidence of these diseases increases progressively with age. Therefore, the changes at the molecular, cellular and physiologic levels that occur during aging profoundly influence the development and progression of these diseases. Functional analysis of WRN will provide a clearer understanding of these changes and will help in the development of therapeutic agents aimed at preventing the early onset of age-associated diseases. PUBLIC HEALTH RELEVANCE: Werner syndrome (WS) is a genetic disease caused by loss of the Werner syndrome protein and predisposes to premature aging and early onset of diseases such as cancer and cardiovascular diseases. The function of the Werner syndrome protein and the role of this protein in cellular homeostasis and preventing normal cells from becoming unhealthy are poorly understood. The studies proposed in this application will be important for elucidating the molecular mechanisms underlying the development of WS pathology, which in turn could lay the foundation for the development of therapeutic approaches to improve the effectiveness of treatments to prevent cancer and other age-onset diseases in the general population.

描述（由申请人提供）：本研究的目的是获得关于维尔纳综合征蛋白（WRN）复合物在维持端粒完整性和防止染色体外端粒环形成的过程中的功能的机制见解。 WRN是一种具有解旋酶和核酸外切酶活性的核蛋白，其功能丧失突变与过早衰老和易患癌症的沃纳综合征（WS）有关。遗传和生化证据表明 WRN 参与端粒代谢，并表明异常的端粒长度稳态会导致 WS 的病理学。我们的生化研究表明，WRN 作为 Ku70/80 异二聚体的功能单元发挥作用，并进一步证明 WRN 功能的丧失会导致表达端粒酶的成纤维细胞产生端粒环。为了确定 WRN 复合物调节端粒稳态的机制，我们建议从机制上表征 WRN、Ku 和染色体末端发现的端粒特异性因子之间的功能相互作用，并定义由负责端粒环形成的 WRN 功能丧失激活的过程。为了实现这些目标，我们提出以下三个目标。在目标 1 中，我们将描述 WRN 及其相互作用伙伴 Ku70/80 在人类细胞端粒末端调节中的作用。在目标 2 中，我们将剖析 WRN 功能丧失导致染色体外 t 环形成的分子机制。在目标 3 中，我们将在体外端粒底物模型的背景下表征 WRN 的生化特性。本申请中提出的研究将阐明 WRN 在端粒中的作用，并为了解 WRN 功能的丧失如何促进基因组不稳定、过早衰老以及癌症和心血管疾病等疾病的早期发作提供有价值的信息。人们认识到这些疾病的发病率随着年龄的增长而逐渐增加。因此，衰老过程中发生的分子、细胞和生理水平的变化深刻影响着这些疾病的发生和发展。 WRN 的功能分析将使人们更清楚地了解这些变化，并将有助于开发旨在预防与年龄相关的疾病早期发作的治疗药物。公共健康相关性：沃纳综合征 (WS) 是一种由沃纳综合征蛋白缺失引起的遗传性疾病，容易导致过早衰老以及癌症和心血管疾病等疾病的早发。人们对维尔纳综合征蛋白的功能以及该蛋白在细胞稳态和防止正常细胞变得不健康中的作用知之甚少。本申请中提出的研究对于阐明 WS 病理学发展的分子机制非常重要，这反过来又可以为开发治疗方法奠定基础，以提高预防癌症和其他老年性疾病的治疗效果。普通民众。