BLEOMYCINS CONTROL OF OXIDATIVE DNA DAMAGE

描述（改编自申请）： 氧化性DNA损伤剂和细胞对这些试剂的反应是 具有重要医学意义的问题。然而，所有 细胞用来防御和修复损伤的机制 知道的本项目的长期目标是确定机制 细胞用来保护免受氧化损伤。具体来说，长期- 长期目标是了解DNA修复途径，恢复 过程和蛋白质在细胞对氧化应激的反应中起重要作用 DNA损伤剂三类氧化性DNA损伤剂是 包括在研究中：电离辐射，抗癌博来霉素和 结构相关的腐皮霉素和过氧化氢。博来霉素 一组抗生素是一种重要的治疗剂， 单药治疗几种人类癌症，并广泛用于 联合化疗和放疗。突变blm 5菌株将是 在拟议的工作中使用，以调查遗传和生物化学 控制氧化损伤。酵母菌的blm突变体 酿酒酵母是分离的基础上，他们的超敏反应， 氧化剂的致命作用。具体目标包括研究 处理和修复细胞暴露于 氧化性DNA损伤剂，并确定BLM 5的作用 基因在维持正常真核DNA功能和修复后 氧化损伤这些研究将增加新的知识， 对DNA修复和代谢以及遗传学领域的重要性。 了解氧化损伤后的引入和修复 而且，只有当所有的主要基因 参与者的身份已得到确认和定性。将获取数据 从细胞和分子水平的相关研究中， 遗传表征、分子生物学和生物化学。这些 包括DNA序列分析、研究DNA损伤方法， 修复，以及透射和扫描电子显微镜。DNA修复 将使用脉冲场电泳，重组 使用酵母质粒修复双DNA断裂，以及有丝分裂 重组测定。实验还包括体外诱变， 无效突变的产生和表征，鉴定 使用双杂交系统识别与蛋白质的相互作用 使用双杂交系统识别相互作用的蛋白质 相互作用的蛋白质，以及从基因组文库中克隆人类同源物。 基因的复杂性，分子的灵活性，以及 突变株S.酿酒厂允许这些研究和技术 接近。在这个项目中获得的独特知识 对细胞研究的重要意义， 确定氧化损伤和修复的机制以及临床 癌症管理

Description (Adapted from Application): Mechanisms of action of oxidative DNA-damaging agents and cellular responses to these agents are problems of considerable medical importance. However, all of the mechanisms cells use to defend against and repair the damage are not known. The long-term goal of this project is to determine mechanisms cells use to protect against oxidative damage. Specifically, the long- term objectives are to understand DNA repair pathways, recovery processes, and proteins important in cellular responses to oxidative DNA-damaging agents. Three classes of oxidative DNA-damaging agents are included in the study: ionizing radiation, anti-cancer bleomycins and structurally related phleomycins, and hydrogen peroxide. The bleomycin group of antibiotics is an important therapeutic agent useful as a single agent in treating several human cancers and widely used in combination chemotherapy and radiotherapy. Mutant blm5 strains will be used in the proposed work to investigate the genetic and biochemical controls of oxidative damage. The blm mutants of Saccharomyces cerevisiae were isolated on the basis of their hypersensitivities to lethal effects of oxidants. Specific aims include studies of the processing and repair of DNA lesions produced after exposure of cells to oxidative DNA-damaging agents, and establishing the role of the BLM5 gene in maintaining normal eukaryotic DNA function and repair after oxidative damage. The studies will add new knowledge of general importance to fields of DNA repair and metabolism, and genetics. Understanding the introduction and repair of lesions after oxidative damage, moreover, will not be completed until all the major genes involved have been identified and characterized. Data will be acquired from interrelated studies at the cellular and molecular levels, using genetic characterization, molecular biology, and biochemistry. These include DNA sequence analyses, methodologies for studying DNA damage and repair, and transmission and scanning electron microscopy. DNA repair will be studied using pulsed-field electrophoresis, recombinational repair of double DNA breaks using yeast plasmids, and mitototic recombination assays. Experiments also include in vitro mutagenesis, the production and characterization of null mutation, identifying interactions with proteins using the two-hybrid system of identifying interacting proteins using the two-hybrid system of identifying interacting proteins, and cloning human homologs from genomic libraries. The genetic sophistication, molecular flexibility, and availability of mutant strains of S. cerevisiae permit these studies and technical approaches. The unique knowledge gained in this project has signification implications for cellular studies directed toward determining mechanisms of oxidant injury and repair as well as clinical cancer management.