Project 1: Synthetic Approaches to Carcinogen-Linked Oxyoligonucleotides

该计划项目互动地使用有机合成、生物分析化学、结构生物学和 分子生物学阐明外源性和内源性双功能的分子细节 烷基化加合物会降低DNA复制和修复能力。努力将重点放在以下两个地点的代理上 DNA可能的亲核攻击被两个或三个碳原子分开。氯氧乙烷，一种 氯乙烯的代谢物是前者和α，β-不饱和醛的一个例子，例如丙烯醛， 巴豆醛和4-羟基壬烯醛就是后者的例子。该计划的一个中心假设 项目是双亲电体可以形成链间和链内的DNA交联物，这种交联物有助于 在加合物的生物学上意义重大。 项目1将开发合成路线，以获得各种类型的加合物，这些加合物可以由这些 亲电体及其结合DNA的区域化学和定位策略 立体化学。拟议的研究旨在解决有关以下方面的假设：1) 肠链内交联物的特征及病变对链内交联物的处理 旁路聚合酶；2)环氧氯丙烷和丙烯醛的N1-da和N3-DC加合物的合成与研究 以及它们的脱氨产物；3)从生物样品中鉴定肠DNA交联物和4) 由N7-DG加合物的水解物衍生的FAPGamma损伤的合成和表征。 要研究的DNA加合物是从广泛分散的环境污染物中衍生或产生的 内源性地通过脂质过氧化。鉴于对这些化合物的广泛接触，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.