Mutagenic hot spots & 3-D structure of damaged DNA

诱变热点

• 批准号: 6443872
• 负责人: SHINYA SHIBUTANI
• 金额: $ 21.9万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6443872
• 关键词: DNA damage; DNA directed DNA polymerase; DNA repair; X ray crystallography; adduct; chemical carcinogen; environmental toxicology; mutagens; nucleic acid sequence; nucleic acid structure; oligonucleotides; phenolic amine

The long-range goals of this research are two-fold; to establish the mutagenic potential of selected environmental mutagens and to explore the molecular basis for recognition and repaired of damaged DNA. Excellent progress has been made during the past project period. Quantitative methods have been developed that allowed us to establish in vitro and in vivo the mutagenic profiles of defined DNA adducts. Fundamental principles have emerged that will facilitate analyses of mutational spectra produced by environmental mutagens. For example, using site-specific techniques, we can predict nucleotide sequence contexts of mutational hot spots. We also discovered that DNA polymerases differ strikingly from one another in their miscoding potential with respect to certain DNA adducts. We also describe a new pathway for repair of oxidative DNA damage in E. coli. In the next project period, we will seek to determine the mutagenic potential in vitro and in vivo for PhIP and 8-aminoguanine, a modified DNA base which accumulates in the liver of animals treated with 2- nitropropane. We will use our experimental systems to explore molecular mechanisms of base substitutions and deletion mutagenesis for abasic sites, aminofluorene adducts and four stereoisomers derived from benzo(a)pyrene. Part of this project is devoted to studies of DNA repair enzymes; we propose to isolate and purify homologs of Fpg protein and MutY protein from mammalian sources. Finally, we will study the interaction of a single zinc finger derived from Fpg protein with damaged DNA.

这项研究的长期目标有两个方面： 选择的环境诱变剂的诱变潜力，并探讨 识别和修复受损DNA的分子基础。 在过去的项目期间取得了很好的进展。 定量方法已经开发出来，使我们能够建立在 确定的DNA加合物的体外和体内致突变特征。 基本原则已经出现，将有助于分析 由环境诱变剂产生的突变谱。例如使用 通过位点特异性技术，我们可以预测 突变热点我们还发现DNA聚合酶 在它们的潜在错误编码方面， 某些DNA加合物我们还描述了一种新的修复途径， E.杆菌 在下一个项目期间，我们将寻求确定 PhIP和8-氨基鸟嘌呤的体外和体内潜力， 在用2-氨基丁酸处理的动物的肝脏中积累的DNA碱基， 硝基丙烷我们将用我们的实验系统来探索分子 无碱基突变的碱基置换和缺失突变机制 位点，氨基芴加合物和四种衍生自 苯并（a）芘。这个项目的一部分致力于DNA修复的研究 酶;我们建议分离和纯化Fpg蛋白的同系物， 来自哺乳动物来源的MutY蛋白。最后，我们将研究 Fpg蛋白锌指结构与损伤蛋白的相互作用 DNA.