Radiation-induced DNA Damage and Transcriptional Mutagenesis in Tumor Development

肿瘤发展中辐射诱导的 DNA 损伤和转录突变

• 批准号: 7492119
• 负责人: Paul William Doetsch
• 金额: $ 29.07万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7492119
• 关键词: 8-Oxoguanine DNA Glycosylase; 8-oxoguanine; Address; Area; Bacteria; Base Excision Repairs; Biological; Biological Assay; Cell Culture System; Cell Cycle Progression; Cell Death; Cells; Chemicals; Class; Cockayne Syndrome; Codon Nucleotides; Condition; DNA; DNA Damage; DNA Repair; DNA Repair Pathway; DNA-Directed DNA Polymerase; DNA-Directed RNA Polymerase; Development; ERCC5 gene; Embryo; End Point; Endonuclease V; Epithelial Cells; Event; Excision Repair; Fibroblasts; Foundations; Future; Genes; Genetic; Genetic Transcription; Goals; Growth; Human; Individual; Interphase Cell; Ionizing radiation; Knock-out; Lead; Left; Lesion; Luciferases; Lung; Mammalian Cell; Mediating; Mismatch Repair; Modeling; Mus; Mutagenesis; Nucleotide Excision Repair; Numbers; OGG1 gene; Oncogene Proteins; Pathway interactions; Phase; Phenotype; Phosphorylation; Phosphotransferases; Physiology; Play; Population; Positioning Attribute; Process; Production; Proteins; RAS genes; Radiation; Radiation Induced DNA Damage; Rate; Reporter; Research Personnel; Rodent; Role; Sequence Analysis; Serum; Signal Pathway; Signal Transduction; Site; System; Transcript; Transcription-Coupled Repair; Tumor Promotion; Uracil; XPGC protein; base; cell growth; cell type; design; insight; mutant; programs; ras Oncogene; ras Proteins; repair enzyme; repaired; research study; tumor

DESCRIPTION (provided by applicant): The genes of all cells are continuously damaged by extrinsic agents such as radiation and chemicals as well as endogenous, spontaneous processes. DMA damage, if left unrepaired, can result in a number of deleterious biological consequences, including the production of mutant proteins that can change the cellular phenotype. Delineating the processes that generate mutant proteins is of great importance for our understanding of the endpoints of genetic damage which include cell death, changes in physiology and, in the case of mammalian cells, tumor development. The vast majorities of DNA damage-induced mutagenesis studies are replication-centric and are based on models of DNA polymerase errors occurring in the vicinity of the lesion. Few studies have addressed the possibility that mutagenesis at the level of transcription (via RNA polymerase encounters with DNA damage) may also be an important pathway for generating mutant proteins, particularly in non-dividing cells. The studies proposed in this project are focused on two major areas: (i) the delineation of the roles that DNA repair excision pathways (in bacterial and mammalian cells) play in transcriptional mutagenesis (TM), and (ii) whether TM can activate a mutant Ras oncogene-mediated signaling pathway related to mammalian tumor development. These studies should substantially increase our understanding of the occurrence and biological relevance of TM as well as provide important insights into the DNA repair systems employed by bacterial and mammalian cells for reversing frequently occurring and ionizing radiation-induced DNA base damages under both growth and non-growth conditions.

描述（由申请人提供）：所有细胞的基因不断受到外部因素（如辐射和化学物质）以及内源性自发过程的破坏。如果不进行修复，DMA损伤会导致许多有害的生物学后果，包括产生可以改变细胞表型的突变蛋白。描述产生突变蛋白的过程对我们理解遗传损伤的终点非常重要，包括细胞死亡、生理变化，以及哺乳动物细胞的肿瘤发展。绝大多数DNA损伤诱导的诱变研究都是以复制为中心的，并且是基于在损伤附近发生的DNA聚合酶错误的模型。很少有研究表明，转录水平的突变（通过RNA聚合酶遇到DNA损伤）也可能是产生突变蛋白的重要途径，特别是在非分裂细胞中。本项目提出的研究主要集中在两个主要领域：(i)描述DNA修复切除途径（在细菌和哺乳动物细胞中）在转录诱变（TM）中的作用，以及（ii） TM是否可以激活与哺乳动物肿瘤发展相关的突变Ras癌基因介导的信号通路。这些研究将大大增加我们对TM的发生和生物学相关性的理解，并为细菌和哺乳动物细胞用于逆转生长和非生长条件下频繁发生和电离辐射诱导的DNA碱基损伤的DNA修复系统提供重要见解。