Project 1: Synthetic Approaches to Carcinogen-Linked Oxyoligonucleotides

该计划项目交互使用有机合成，生物分析化学，结构生物学， 分子生物学来阐明外源性和内源性双功能 烷基化加合物降解DNA复制和修复。努力将集中在代理商，其中两个网站的 DNA可能的亲核攻击被两个或三个碳原子隔开。氯环氧乙烷，a 氯乙烯的代谢物是前者和α，β-不饱和醛，如丙烯醛， 巴豆醛和4-羟基壬烯醛是后者的实例。该计划的一个核心假设是 双亲电体可以形成链间和链内DNA交联，这种交联有助于 在加合物的生物学中有着重要的意义。 项目1将开发合成路线的各种类型的加合物，可以形成这些 亲电试剂及其以确定的区域化学位点特异性掺入DNA的策略， 立体化学拟议的研究旨在解决有关以下问题的假设：1） 链内烯醛交联的表征和损伤对链内交联的处理 2）氯环氧乙烷与丙烯醛的N1-dA和N3-dC加合物的合成与研究 和它们的脱氨基产物; 3）从生物样品中鉴定烯醛的DNA交联;和4） 合成和表征衍生自N7-dG加合物水解的FAP γ损伤。 待研究的DNA加合物来自广泛分散的环境污染物或产生的 通过脂质过氧化作用内源性。鉴于这些化合物的广泛暴露，我们的研究将 直接应用于人类健康问题。

This Program Project interactively uses organic synthesis, bioanalytical chemistry, structural biology, and molecular biology to elucidate the molecular details by which exogenous and endogenous bifunctional alkylating adducts degrade DNA replication and repair. Efforts will focus on agents in which the two sites of possible nucleophilic attack by the DNA are separated by either two or three carbon atoms. Chlorooxirane, a metabolite of vinyl chloride, is an example of the former and alpha, beta-unsaturated aldehydes, such as acrolein, crotonaldehyde and 4-hydroxynonenal, are examples of the latter. A central hypothesis of this Program Project is that bis-electrophiles can form inter- and intrastrand DNA crosslinks and such crosslinks contribute significantly in the biology of the adducts. Project 1 will develop synthetic routes to the various types of adducts that can be formed by these electrophiles and strategies for their site-specific incorporation into DNA with defined regiochemistry and stereochemistry. The proposed studies are designed to address hypotheses concerning the following: 1) the characterization of intrastrand enal crosslinks and the processing of the intrastrand crosslinks by lesion bypass polymerases; 2) the synthesis and study of N1-dA and N3-dC adducts of Chlorooxirane and acrolein and their deamination products; 3) identification of DNA crosslinks of enals from biological samples and 4) the synthesis and characterization of FAPgamma lesions that are derived from hydrolysis of N7-dG adducts. The DNA adducts to be studied are derived from widely dispersed environmental pollutants or produced endogenously through lipid peroxidation. Given the wide exposure to these compounds, our studies will have direct applications to human health concerns.