STRUCTURE AND MECHANISM OF DNA INTERSTRAND CROSS-LINKING

DNA链间交联的结构和机制

• 批准号: 2183413
• 负责人: PAUL B HOPKINS
• 金额: $ 13.67万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 1998-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2183413
• 关键词: DNA damage; chromium; cis platinum compound; crosslink; intermolecular interaction; mechlorethamine; nitrogen mustard; nitrosourea; nucleic acid hybridization; nucleic acid sequence; nucleic acid structure; oligonucleotides; toxin

Many antitumor agents and toxic substances, including important environmental pollutants, exert their toxic effects by chemical reaction with DNA. In numerous cases, the regions of DNA which react with these substances and the structures of the resulting products are unknown. Understanding these details is critical to understanding the toxic effects of these substances. The proposed research will examine issues of chemical and biochemical significance arising from the interaction of antitumor agents, toxins, and toxicants with nucleic acids. The specific aims include: (1) We will evaluate the sequence specificity of cross-linking and solution structure of cross-linked DNAs derived from DNA interstrand cross-linking agents synthesized during the previous grant period which were designed to recognize and cross-link sequences up to 6 nucleotides in length. (2) We will quantify the sequence specificity, yield, and structures of the dG-to-dG intrastrand cross-links caused by mechlorethamine in duplex DNA, probe the origin of the unexpected interstrand cross- linking sequence specificity of mechlorethamine by studying a structural analog which extends the distance between the electrophiles, survey the efficiency and sequence specificity for interstrand cross- linking of DNA with other nitrogen mustards, and evaluate the impact of the mechlorethamine DNA-DNA interstrand cross-link on the affinity of proteins which recognize bent DNA in collaboration with Professor Essigmann. (3) We will define the covalent structure of the dG-to-dG cisplatin induced DNA-DNA interstrand cross-link at 5'-d(Gc) and determine the affinity of a 100-mer duplex containing this cross-link at a defined site for an HMG-family protein in collaboration with Professor Essigmann. (4) We will establish the DNA-DNA interstrand cross-linking sequence specificity and covalent structure of the nitrosourea-, chloroacetaldehyde-, and chromium(Vl)-induced interstrand cross-links. (5) We will determine whether RNA-DNA hybrid duplexes can be cross- linked by any of seven bifunctional electrophiles. These results could contribute background information necessary for the eventual rational design of agents targeted to react covalently with the RNA-DNA duplex.

许多抗肿瘤药物和有毒物质，包括重要的 环境污染物，通过化学作用发挥其毒性作用 与DNA发生反应。在许多情况下，DNA的反应区域 这些物质和产物的结构是 未知。了解这些细节对于理解 这些物质的毒性作用。拟议的研究将检查 关于化学和生物化学的重要性的问题 抗肿瘤药物、毒素和毒物与核酸的相互作用 酸。具体目标包括： (1)我们将评估交联剂和交联剂的序列特异性 DNA链间交联DNA的溶液结构 在上一次赠款期间合成的交联剂 被设计成识别和交叉连接多达6个核苷酸的序列 在篇幅上。 (2)我们将对序列的特异性、产量和结构进行量化 甲氧氯乙胺引起的DG-DG链内交联链的研究 双链DNA，探索意外的链间交叉的起源- 甲氧基氯乙胺的连接序列特异性研究 延长亲电体之间距离的结构模拟， 考察了链间杂交的效率和序列特异性 DNA与其他氮素芥菜的连接，并评估其影响 甲氰菊胺DNA-DNA链间交联对亲和力的影响 识别弯曲DNA的蛋白质与教授合作 埃西格曼。 (3)确定DG-to-DG顺铂的共价结构 在5‘-d(GC)诱导DNA-DNA链间交联，并测定 含此交联物的100聚体双链的亲和力 HMG家族蛋白的网站，与教授合作 埃西格曼。 (4)建立DNA-DNA链间交联序列 亚硝脲的专一性和共价结构， 氯乙醛和铬(Vl)诱导的链间交联。 (5)我们将确定RNA-DNA杂交双链是否可以交叉- 由七种双功能亲电剂中的任何一种连接。这些结果可能 为最终的Rational提供必要的背景信息 旨在与RNA-DNA双链发生共价反应的试剂的设计。