Biological Effects of DNA Adducts Formed by Nitroaromatic Compounds

硝基芳香族化合物形成的 DNA 加合物的生物学效应

• 批准号: 8067870
• 负责人: Ashis K Basu
• 金额: $ 31.48万
• 依托单位: UNIVERSITY OF CONNECTICUT STORRS
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-02-01 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8067870
• 关键词: 1-Nitropyrene; Affect; Aphidicolin; Base Pairing; Biological; Biological Assay; Bypass; Carcinogens; Cell Extracts; Cell Line; Cells; Complement; Complex; DNA; DNA Adducts; DNA Damage; DNA-Directed DNA Polymerase; Diesel Exhaust; Embryo; Environmental Pollutants; Enzymes; Escherichia coli; Etiology; Family; Frequencies; Gene Mutation; Genes; Genetic; Goals; Guanine; Health; Human; In Vitro; Investigation; Kinetics; Lesion; Light; Malignant Neoplasms; Malignant neoplasm of lung; Mammalian Cell; Methods; Mismatch Repair; Modeling; Molecular; Mutagenesis; Mutagens; Mutation; Nucleotides; Oligonucleotides; Oncogenes; Pattern; Plasmid Cloning Vector; Play; Polymerase; Property; Proteins; Public Health; Research; Research Design; Role; Saccharomyces cerevisiae; Sampling; Single-Stranded DNA; Site; Sulfolobus solfataricus; Techniques; Testing; Viral Vector; Work; adduct; base; ds-DNA; genotoxicity; in vivo; inhibitor/antagonist; insight; interest; kidney cell; malignant breast neoplasm; pollutant; polymerization; prototype; public health relevance; repaired

DESCRIPTION (provided by applicant): The goal of this application is to investigate the mechanism by which nitroaromatic carcinogens cause mutations. We shall focus on the major DNA adducts formed by the nitropyrenes, the primary mutagenic pollutants in diesel exhaust, but also plan to initiate work on the DNA adducts of 3-nitrobenzanthrone, a recently discovered potent mutagenic and carcinogenic contaminant in diesel. We hypothesize that a group of DNA adducts formed by these nitroarenes play important roles in the etiology of human cancer via the mutagenic effects in crucial sequences of cancer genes (e.g., p53). We also hypothesize that most of these mutations occur via error-prone bypass of the lesions by Y-family DNA polymerases. In order to test these hypotheses, we shall synthesize and characterize oligonucleotides containing the major guanine adducts of 1-nitropyene, 1,6- and 1,8-dinitropyere, and 3-nitrobenzanthrone in important gene sequences. These adduct-containing oligonucleotides will be used to construct single-stranded plasmid or viral vectors and mutagenicity and genotoxicity will be evaluated in Escherichia coli and mammalian cells. The effect of specific repair or replication proteins will be assessed by using repair-proficient and -deficient cell lines or inhibitors. The cellular studies will be complemented by investigating in vitro kinetics and fidelity of polymerization catalyzed by Dpo4 and four human Y- family DNA polymerases. Initially, we shall focus on the C8 guanine adduct of 1-nitropyrene. The translesion synthesis products will be sequenced to determine the mutagenic pattern caused by each DNA polymerase. Finally, duplex plasmid vectors with these adducts will be constructed, and progression of replication fork will be examined in human cell extracts to determine if each adduct is significant block to fork progression. Mutational types and frequencies in double-stranded DNA will be determined. Together, these studies will provide a deeper understanding of the mechanism of mutagenesis induced by the DNA adducts of these nitroaromatic carcinogens. PUBLIC HEALTH RELEVANCE: Nitroaromatic compounds have been detected in a variety of environmental samples, including diesel exhaust. These compounds are potent mutagens and carcinogens, and it has been suggested that some of these pollutants play a role in human lung and breast cancer. Therefore, investigation of the mechanism by which the nitroaromatic carcinogens cause mutations has high significance to public health.

描述（由申请人提供）：本申请的目的是研究硝基芳族致癌物引起突变的机制。我们将重点关注由硝化剂形成的主要DNA加合物，氮气排气中的主要诱变污染物，但也计划启动在3-硝基苯甲酮的DNA加合物上工作，这是最近发现的有效的诱变和癌变的柴油机中的有效的诱变和癌变。我们假设，这些硝化苯子形成的一组DNA加合物通过癌症基因的关键序列中的诱变作用在人类癌症的病因中起重要作用（例如，p53）。我们还假设大多数这些突变是通过Y-家庭DNA聚合酶易于旁路的旁路发生的。为了检验这些假设，我们将合成并表征含有1-硝基二氮，1,6-和1,8-二硝基拷贝的主要鸟嘌呤加合物和重要基因序列中3-硝基苯噻噻诚的寡核苷酸。这些含加合物的寡核苷酸将用于构建单链质粒或病毒载体，诱变性和遗传毒性将在大肠杆菌和哺乳动物细胞中进行评估。特异性修复或复制蛋白的影响将通过使用可修复的细胞系或抑制剂来评估。细胞研究将通过研究体外动力学和由DPO4催化的聚合和四种人Y-家族DNA聚合酶催化的聚合的忠诚度补充。最初，我们将重点关注1-硝基吡啶的C8鸟嘌呤加合物。将测序的跨质量合成产物确定每个DNA聚合酶引起的诱变模式。最后，将构建具有这些加合物的双链质粒向量，并将在人类细胞提取物中检查复制叉的进展，以确定每个加合物是否对叉进展是否显着阻碍。将确定双链DNA中的突变类型和频率。总之，这些研究将更深入地了解这些硝化癌的DNA加合物引起的诱变的机理。 公共卫生相关性：在包括柴油排气在内的各种环境样品中发现了硝化化合物。这些化合物是有效的诱变剂和致癌物，有人提出其中一些污染物在人类肺和乳腺癌中起作用。因此，调查氮气致癌物引起突变的机制对公共卫生具有很高的意义。