Mutagenic hot spots & 3-D structure of damaged DNA

诱变热点

• 批准号: 6301315
• 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: 2000
• 资助国家: 美国
• 起止时间: 2000-04-10 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6301315
• 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

During the last project period, we used a single strand shuttle vector system to establish the mutagenic potential and specificity of selected DNA adducts. In addition, we developed a new procedure for the analysis of tamoxifen-DNA adducts and used it to demonstrate the genotoxicity of procedure for the analysis of tamoxifen-DNA adducts and used it to demonstrate the genotoxicity for this drug for the human endometrium. We reported that the adenine DNA glycosylase MutY forms a long-lived intermediate with DNA, thereby preventing double strand breaks during DNA repair. We cloned the mouse and human cognate genes for Ogg1 and showed that the gene product is a functional homolog of Fpg protein in bacteria. Future studies are designed to determine the mutagenic potential of selected environmental mutagens including bisphenol-A. We will use a new double strand vector that reveals the relative contribution of translesion synthesis, excision repair, and recombination events (damage tolerance) in the cellular processing of DNA damage in mammalian cells. We will also study mutation hot spots and related sequence context effects with respect to the reactivity proximate carcinogens with DNA. These experiments lay ground for future studies in molecular epidemiology in which adduct levels in humans are related to mutations observed in the P-53 gene. Using x-ray crystallographic techniques, we proposed to establish three dimensional structures of DNA containing defined lesions as a duplex oligonucleotide and as a ternary complex with rat liver DNA polymerase beta. These structural studies address our long-range goal of relating molecular structure and biological function.

在最后一个项目期间，我们使用单链穿梭矢量系统来建立所选DNA加合物的诱变潜力和特异性。此外，我们开发了一种分析他莫昔芬-DNA加合物的新程序，并将其用来证明了他莫昔芬-DNA加合物的分析程序的遗传毒性，并将其用于证明人类子宫内膜的这种药物的遗传毒性。我们报道说，腺嘌呤DNA糖基化合酶突变形成了长期寿命的与DNA的中间体，从而防止了在DNA修复过程中的双链断裂。我们将小鼠和人类的同源基因克隆了OGG1，并表明该基因产物是细菌中FPG蛋白的功能同源物。未来的研究旨在确定包括双酚-A在内的选定环境诱变剂的诱变潜力。我们将使用一种新的双链矢量，该载体揭示了跨性别细胞中DNA损伤的细胞加工中跨性别合成，切除修复和重组事件（损伤耐受性）的相对贡献。我们还将研究突变热点和相关序列上下文对与DNA接近反应性致癌物的影响。这些实验为未来的分子流行病学研究提供了基础，在分子流行病学中，人类加合物水平与P-53基因中观察到的突变有关。使用X射线晶体学技术，我们提议建立含有定义病变的DNA的三维结构，这些结构是双链寡核苷酸作为双链寡核苷酸，以及带有大鼠肝脏DNA聚合酶β的三元络合物。这些结构研究涉及我们将分子结构和生物学功能关联的远程目标。