Excision Repair of Environmental Telomere Damage

环境端粒损伤的切除修复

基本信息

批准号：
10397054
负责人：
Patricia L Opresko
金额：
$ 91.26万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-01 至 2027-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10397054
关键词：
Animal Model Award Cell Culture Techniques Cell Proliferation Cell physiology Cells Chromosomes Chronic DNA Damage DNA lesion Degenerative Disorder Excision Repair Functional disorder Funding Generations Genetic Genome Stability Genotoxic Stress Goals Guanine Health Human Knowledge Learning Lesion Maintenance Measures Mus National Institute of Environmental Health Sciences Organ Organism Outcome Oxidative Stress Pathway interactions Phase Phenotype Population Proteins Research System Technology Telomere Maintenance Telomere Shortening Transgenic Organisms Translating Work Zebrafish base cancer cell cancer prevention carcinogenesis cell type experimental study flexibility human tissue innovation nucleobase preservation programs repaired telomere telomere loss tool

Animal Model Award Cell Culture Techniques Cell Proliferation Cell physiology Cells Chromosomes Chronic DNA Damage DNA lesion Degenerative Disorder Excision Repair Functional disorder Funding Generations Genetic Genome Stability Genotoxic Stress Goals Guanine Health Human Knowledge Learning Lesion Maintenance Measures Mus National Institute of Environmental Health Sciences Organ Organism Outcome Oxidative Stress Pathway interactions Phase Phenotype Population Proteins Research System Technology Telomere Maintenance Telomere Shortening Transgenic Organisms Translating Work Zebrafish base cancer cell cancer prevention carcinogenesis cell type experimental study flexibility human tissue innovation nucleobase preservation programs repaired telomere telomere loss tool

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项目摘要

Summary Numerous studies in human populations, human tissue, animal models and cell culture demonstrate that environmental genotoxic and oxidative stress are associated with accelerated telomere shortening and dysfunction. Telomeres at chromosome ends are essential for genome stability and sustained cell proliferation, and dysfunctional telomeres contribute to degenerative diseases and carcinogenesis in humans. The goals of this project are to advance exciting discoveries and highly innovative work from two NIEHS funded R01 awards investigating the consequences of nucleobase damage and excision repair at telomeres. The overarching hypothesis for this R35 proposal is that telomere shortening and dysfunction caused by environmental genotoxic and oxidative stress, occurs via formation of specific base lesions and toxic repair intermediates that directly interfere with telomere replication and maintenance. Working with collaborators we pioneered a highly innovative chemoptogenetic tool that selectively induces DNA lesions at telomeres. This technology is transformative because targeting well-defined base damage to telomeres allows us to unequivocally attribute phenotypic changes and health outcomes to the induced telomere lesions, eliminating confounding effects of damage elsewhere. We fully validated this system for the targeted formation of a common oxidative guanine lesion at telomeres, and remarkably, we discovered that the chronic generation this lesion induces profound hallmarks of telomere dysfunction that mimic genetic loss of telomere shelterin proteins. This project will probe and uncover the mechanisms of DNA lesion induced telomere loss and dysfunction. A major strategy is to extend and modify this flexible technology in a phased approach for introducing base damage, toxic repair intermediates, bulky monoadducts, and other lesion types. We will measure various cellular and telomeric endpoints after lesion induction and will use candidate and unbiased approaches to identify proteins required to protect telomeres against the various forms of environmentally relevant DNA damage. This chemoptogenetic tool has been adapted for use in model organisms, and as the R35 evolves we will translate what we learn in cell culture to experiments in transgenic zebrafish and mice. Using this system, we will generate telomeric damage in key organs and cell types and will measure the impact on organ function and health. This program will lead to significant advances in mechanistic understanding of how environmentally relevant forms of telomeric DNA lesions impact telomere function, cellular function, and organism health. Ultimately, knowledge gained from this program will be highly valuable for developing new strategies that 1) preserve telomeres to ameliorate the effects of genotoxic and oxidative stress in healthy cells or conversely, that 2) inhibit telomere maintenance in malignant cells to arrest proliferation.

概括人类人群，人组织，动物模型和细胞培养的大量研究表明环境遗传毒性和氧化应激与加速的端粒缩短和功能障碍。染色体末端的端粒对于基因组稳定性和持续细胞至关重要增殖和功能障碍端粒有助于人类的退化性疾病和致癌作用。该项目的目标是提高两个Niehs的令人兴奋的发现和高度创新的工作资助了R01奖项，研究了端粒核酶损伤和切除修复的后果。该R35提案的总体假设是端粒缩短和功能障碍环境遗传毒性和氧化应激是通过特定碱病变和有毒修复的形成而发生的中间直接干扰端粒复制和维护。与合作者合作开创了一种高度创新的化学遗传学工具，可有选择地诱导端粒的DNA病变。这技术具有变革性，因为针对定义明确的基本损害对端粒的损害使我们能够明确地将表型变化和健康结果归因于诱导的端粒病变，消除了在其他地方造成的损害的混淆。我们完全验证了该系统的目标形成端粒处的常见氧化鸟嘌呤病变，非常明显的是，我们发现慢性一代病变诱导端粒功能障碍的深刻标志，即模仿端粒庇护所的遗传丧失蛋白质。该项目将探测并发现DNA病变引起的端粒损失和功能障碍。一个主要策略是通过分阶段的方法扩展和修改这种灵活的技术引入基本损害，有毒修复中间体，笨重的单核和其他病变类型。我们将在病变诱导后测量各种细胞和端粒端点，并将使用候选者和公正识别保护端粒所需的蛋白质的方法相关的DNA损伤。该化学发生工具已适用于模型生物，并作为 R35进化，我们将将我们在细胞培养的知识转化为转基因斑马鱼和小鼠的实验。使用此系统，我们将在关键的器官和细胞类型中产生端粒损伤，并将测量影响关于器官功能和健康。该计划将导致对机械理解的重大进步端粒DNA病变与环境相关的形式如何影响端粒功能，细胞功能和生物体健康。最终，从该计划中获得的知识对于开发新的知识将非常有价值 1）保留端粒以改善健康细胞中遗传毒性和氧化应激的影响或者相反，2）抑制恶性细胞中的端粒维持以阻止增殖。