DNA Cross-linking by diepoxybutane

二环氧丁烷 DNA 交联

• 批准号: 7996005
• 负责人: NATALIA Y TRETYAKOVA
• 金额: $ 20.11万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7996005
• 关键词: 1,3-Butadiene; 3,4-epoxy-1-butene; Adenine; Alkylating Agents; Automobile Exhaust; Base Pairing; Biological; Butylene Glycols; Bypass; Carcinogens; Characteristics; Chemicals; Complex Mixtures; Cyclization; DNA; DNA Adducts; DNA Alkylation; DNA Repair; DNA Structure; DNA alkyltransferase; DNA lesion; DNA repair protein; Data; Detection; Epidemiologic Studies; Ethylene Oxide; Excision; Exposure to; Gene Mutation; Goals; Guanine; Health; Hematologic Neoplasms; High Pressure Liquid Chromatography; Human; Hydrolysis; Inhalation Exposure; Laboratories; Laboratory Animals; Laboratory Rat; Laboratory mice; Lesion; Lung Neoplasms; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Metabolic Activation; Methodology; Methods; Molecular; Molecular Conformation; Molecular Structure; Mus; Mutagenesis; Mutation; Organism; Pathway interactions; Physiological; Play; Point Mutation; Positioning Attribute; Preparation; Prevalence; Progress Reports; Property; Proteins; Proteomics; Publishing; Rattus; Reaction; Research; Risk; Risk Assessment; Role; Site; Site-Directed Mutagenesis; Specificity; Structure; Testing; Tissue Extracts; Tissues; Tobacco smoke; Uncertainty; Work; adduct; base; cancer risk; carcinogenesis; cigarette smoking; crosslink; cytotoxic; cytotoxicity; design; ds-DNA; erythritol anhydride; exposed human population; human DNA; improved; in vivo; innovation; insight; leukemia; repaired; research study; tool

DESCRIPTION (provided by applicant): 1,2,3,4-diepoxybutane (DEB) is a genotoxic intermediate produced upon the metabolic activation of 1,3-butadiene (BD), a known human carcinogen produced industrially and found in automobile exhaust and in cigarette smoke. DEB is the most mutagenic and cytotoxic metabolite of BD and is likely to play an important role in BD-induced carcinogenesis. The presence of two oxirane groups within the molecular structure of DEB allows it to form DNA-DNA cross-links by consecutively alkylating two adjacent nucleobases in a DNA duplex. In addition, DEB can form potentially promutagenic exocyclic lesions by alkylating two sites of the same DNA base. The long-range goal of our research is to establish the molecular mechanisms by which bifunctional alkylating agents elicit their biological effects. The objective of this project is to identify specific DNA lesions responsible for the genotoxic effects of DEB and BD. The central hypothesis of this research is that DEB forms DNA-DNA cross-links and exocyclic adducts that accumulate in target tissues, contributing to the observed carcinogenic and mutagenic properties of BD. Our proposed studies will improve the current understanding of the mechanisms of mutagenesis and cytotoxicity resulting from BD exposure by providing key information about bifunctional DEB-DNA adducts, including their formation in vivo following exposure to BD, their effects on DNA structure, mispairing characteristics, and cellular repair. We will be pursuing the following four Specific Aims: 1. Quantify bifunctional DEB-DNA lesions in vivo following inhalation exposure to 1,3-butadiene. A sensitive and specific mass spectrometry-based methodology will be used to analyze DNA-DNA cross-links and exocyclic DEB adducts in DNA extracted from tissues of mice and rats exposed to BD. 2. Determine the effects of bifunctional DEB-DNA adducts on DNA duplex structure and replication. Structural analyses by NMR will be performed to analyze adduct conformations in double stranded DNA, while site specific mutagenesis experiments will determine translesion bypass efficiencies and mutational properties of each DEB-DNA adduct. 3. Analyze the repair of bifunctional DEB-DNA adducts. We will identify the major DNA repair mechanisms responsible for the removal of DEB-DNA adducts and analyze the relationships between adduct conformations and repair efficiency. 4. Characterize DNA-protein cross-linking by DEB. A combination of proteomics and immunological detection will be used to investigate DNA-protein cross-linking by DEB as an additional pathway to cytotoxicity and mutagenesis of BD. Collectively, these studies will identify bifunctional DNA adducts responsible for the biological activity of BD and afford new insights into the mechanisms of its mutagenicity and cytotoxicity, reducing the uncertainty in cancer risk assessment for human exposure to BD. PUBLIC HEALTH RELEVANCE: This work will investigate the mechanisms of biological activity of 1,2,3,4-diepoxybutane, a genotoxic intermediate produced upon the metabolic activation of 1,3-butadiene (BD), a known human carcinogen produced industrially and found in automobile exhaust and in cigarette smoke. We will analyze the formation of diepoxybutane -DNA adducts in laboratory animals exposed to BD and examine their ability to induce DNA mutations.

描述（由申请人提供）：1，2，3，4-二环氧丁烷（DEB）是一种遗传毒性中间体，在1，3-丁二烯（BD）代谢活化时产生，BD是一种已知的人类致癌物，在工业上生产，并在汽车尾气和香烟烟雾中发现。DEB是BD最具致突变性和细胞毒性的代谢产物，可能在BD致癌过程中发挥重要作用。在DEB的分子结构中存在两个环氧乙烷基团允许其通过连续烷基化DNA双链体中的两个相邻核碱基来形成DNA-DNA交联。此外，DEB可通过烷基化相同DNA碱基的两个位点形成潜在的促突变性环外病变。我们研究的长期目标是建立双功能烷化剂引起其生物学效应的分子机制。本项目的目的是确定负责DEB和BD的遗传毒性效应的特定DNA损伤。这项研究的中心假设是，DEB形成DNA-DNA交联和环外加合物，在靶组织中积累，有助于观察到的BD的致癌性和致突变性。我们提出的研究将提高目前的理解的诱变和细胞毒性的机制，从BD曝光，通过提供关键信息的双功能DEB-DNA加合物，包括它们的形成在体内暴露于BD后，其对DNA结构的影响，错配特征，和细胞修复。我们将追求以下四个具体目标：1。定量吸入暴露于1，3-丁二烯后体内双功能DEB-DNA损伤。一个敏感和具体的质谱为基础的方法将用于分析DNA-DNA交联和环外DEB加合物的DNA提取的组织暴露于BD的小鼠和大鼠。2.确定双功能DEB-DNA加合物对DNA双链体结构和复制的影响。将通过NMR进行结构分析以分析双链DNA中的加合物构象，而位点特异性诱变实验将确定每个DEB-DNA加合物的translesion旁路效率和突变特性。3.分析双功能DEB-DNA加合物的修复。我们将确定负责去除DEB-DNA加合物的主要DNA修复机制，并分析加合物构象和修复效率之间的关系。4.通过DEB表征DNA-蛋白质交联。将使用蛋白质组学和免疫学检测的组合来研究DEB的DNA-蛋白质交联作为BD的细胞毒性和致突变的额外途径。总的来说，这些研究将确定负责BD生物活性的双功能DNA加合物，并对其致突变性和细胞毒性机制提供新的见解，减少人类暴露于BD的癌症风险评估的不确定性。公共卫生相关性：这项工作将调查1，2，3，4-二环氧丁烷的生物活性的机制，1，3-丁二烯（BD），一个已知的人类致癌物，在工业生产和汽车尾气和香烟烟雾中发现的代谢活化后产生的遗传毒性中间体。我们将分析暴露于BD的实验室动物中二环氧丁烷-DNA加合物的形成，并检查其诱导DNA突变的能力。