Sequence Effects of Arylamine-DNA Adducts: Repair and Replication

芳胺-DNA 加合物的序列效应：修复和复制

• 批准号: 8228104
• 负责人: Bongsup P Cho
• 金额: $ 28.88万
• 依托单位: UNIVERSITY OF RHODE ISLAND
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8228104
• 关键词: Accounting; Affinity; Aromatic Amines; Binding; Cancer Etiology; Carcinogens; Cells; Complex; DNA; DNA Adduction; DNA Adducts; DNA Damage; DNA Polymerase I; DNA-Protein Interaction; Data; Deletion Mutation; Development; Differential Scanning Calorimetry; EMSA; Electrostatics; Entropy; Environment; Equilibrium; Escherichia coli; Etiology; Fluorescence Spectroscopy; Funding; Gel; Goals; Health; Heterogeneity; Hot Spot; Human; Induced Mutation; Investigation; Kinetics; Knowledge; Lesion; Link; Location; Malignant Neoplasms; Methodology; Methods; Molecular; Molecular Conformation; Molecular Probes; Mutagenesis; Mutation; Nucleotide Excision Repair; Outcome; Pathway interactions; Physiological; Plasma; Play; Polymerase; Population; Prevention; Primer Extension; Procedures; Process; Property; Proteins; Replication-Associated Process; Research; Risk Assessment; Role; Scanning; Simulate; Specificity; Structure; Surface; Surface Plasmon Resonance; Surgical incisions; System; Testing; Thermodynamics; Work; XPA gene; adduct; adverse outcome; base; cancer initiation; chemical carcinogenesis; conformer; design; enthalpy; environment related cancer; environmental chemical; grasp; human tissue; in vivo; innovation; insight; programs; prototype; public health relevance; repaired; research study; structural biology; theories; tool

DESCRIPTION (provided by applicant): The long term goal of our research program is to elucidate the molecular mechanisms of DNA adduct-induced chemical carcinogenesis. Aromatic amines are well-known environmental human carcinogens. In particular, arylamine-DNA adduct formation has been confirmed in various human tissues and is believed to induce mutation. We have previously shown that arylamine adducts in DNA exist in three well-defined conformations: stacked (S), external B-type (B), and wedge (W). The conformation depends on the location of the carcinogen moiety in the DNA molecule, and the population ratios of the types under physiological conditions are sequence-dependent. In this application, we hypothesize that arylamine-induced repair and mutation is conformation-specific (S, B, W). We propose four major aims to help define adduct conformation and examine their specific effects on repair (initial damage recognition) and replication (replication fork heterogeneity). Specifically, these aims focus on: (1) conformation-specific repair in a human nucleotide excision repair (NER) system and long-range sequence effects, (2) damage recognition (protein-DNA interaction) (3) the thermodynamics of sequence-dependent slippage-induced frameshift mutagenesis, and (4) replication fork conformational heterogeneity and polymerase binding. We will employ not only existing dynamic 19F NMR/CD, EMSA and fluorescence spectroscopy, but also innovative chip-based surface plasma resonance (SPR) and differential scanning calorimetric (DSC) procedures, creating a powerful suite of biophysical methodologies. Successful completion of the proposed aims will help us gain a better grasp on the protein-DNA interactions involved in human NER and trans-lesion synthesis, which have important implications for resolving the molecular details of cancer etiology. Such knowledge will also be of help in the development of sensible prevention and risk assessment strategies. PUBLIC HEALTH RELEVANCE: The primary causes of sporadic human cancers are environmental. Aromatic amines are among the most notorious environmental chemicals that are implicated in the etiology of human cancers. Formation of arylamine-DNA adducts has been confirmed in various human tissues and is believed to induce chemical carcinogenesis. Hence it is imperative to elucidate how these lesions are repaired and replicated in vivo at the atomic and molecular levels. The key molecular players (adduct structures, polymerases, repair proteins) producing adverse outcomes must be identified, characterized, and understood in order to devise appropriate prevention and risk assessment strategies.

描述（由申请人提供）：我们研究计划的长期目标是阐明DNA加合物诱导化学致癌的分子机制。芳香胺是众所周知的人类环境致癌物。特别是，芳基胺-DNA 加合物的形成已在多种人体组织中得到证实，并被认为会诱导突变。我们之前已经证明DNA中的芳基胺加合物以三种明确的构象存在：堆叠（S）、外部B型（B）和楔形（W）。其构象取决于致癌物部分在DNA分子中的位置，并且生理条件下该类型的群体比例取决于序列。在此应用中，我们假设芳胺诱导的修复和突变是构象特异性的（S、B、W）。我们提出了四个主要目标来帮助定义加合物构象并检查它们对修复（初始损伤识别）和复制（复制叉异质性）的具体影响。具体来说，这些目标集中在：（1）人类核苷酸切除修复（NER）系统中的构象特异性修复和长程序列效应，（2）损伤识别（蛋白质-DNA相互作用）（3）序列依赖性滑移诱导移码诱变的热力学，以及（4）复制叉构象异质性和聚合酶结合。我们不仅将采用现有的动态 19F NMR/CD、EMSA 和荧光光谱，还将采用基于芯片的创新表面等离子体共振 (SPR) 和差示扫描量热 (DSC) 程序，创建一套强大的生物物理方法。成功完成所提出的目标将有助于我们更好地掌握人类 NER 和跨损伤合成中涉及的蛋白质-DNA 相互作用，这对于解决癌症病因学的分子细节具有重要意义。这些知识也将有助于制定明智的预防和风险评估策略。 公共卫生相关性：散发性人类癌症的主要原因是环境。芳香胺是最臭名昭著的环境化学物质之一，与人类癌症的病因有关。芳基胺-DNA 加合物的形成已在多种人体组织中得到证实，并被认为会诱导化学致癌作用。因此，有必要阐明这些损伤如何在原子和分子水平上在体内修复和复制。必须识别、表征和理解产生不良结果的关键分子参与者（加合物结构、聚合酶、修复蛋白），以便制定适当的预防和风险评估策略。