Crosslinking reactions of 4-amino-6-oxo-2-vinylpyrimidine with guanine derivatives and structural analysis of the adducts
作者:Shuhei Kusano、Shogo Ishiyama、Sik Lok Lam、Tsukasa Mashima、Masato Katahira、Kengo Miyamoto、Misako Aida、Fumi Nagatsugi
DOI:10.1093/nar/gkv797
日期:2015.9.18
DNA interstrand crosslinks (ICLs) are the primary mechanism for the cytotoxic activity of many clinical anticancer drugs, and numerous strategies for forming ICLs have been developed. One such method is using crosslink-forming oligonucleotides (CFOs). In this study, we designed a 4-amino-6-oxo-2-vinylpyrimidine (AOVP) derivative with an acyclic spacer to react selectively with guanine. The AOVP CFO exhibited selective crosslinking reactivity with guanine and thymine in DNA, and with guanine in RNA. These crosslinking reactions with guanine were accelerated in the presence of CoCl2, NiCl2, ZnCl2 and MnCl2. In addition, we demonstrated that the AOVP CFO was reactive toward 8-oxoguanine opposite AOVP in the duplex DNA. The structural analysis of each guanine and 8-oxoguanine adduct in the duplex DNA was investigated by high-resolution NMR. The results suggested that AOVP reacts at the N2 amine in guanine and at the N1 or N2 amines in 8-oxoguanine in the duplex DNA. This study demonstrated the first direct determination of the adduct structure in duplex DNA without enzyme digestion.
DNA 链间交联(ICL)是许多临床抗癌药物产生细胞毒性活性的主要机制,目前已开发出许多形成 ICL 的策略。其中一种方法是使用交联形成寡核苷酸(CFO)。在这项研究中,我们设计了一种带有无环间隔的 4-氨基-6-氧代-2-乙烯基嘧啶(AOVP)衍生物,可选择性地与鸟嘌呤发生反应。AOVP CFO 与 DNA 中的鸟嘌呤和胸腺嘧啶以及 RNA 中的鸟嘌呤具有选择性交联反应。在 CoCl2、NiCl2、ZnCl2 和 MnCl2 的存在下,这些与鸟嘌呤的交联反应会加速。此外,我们还证明了 AOVP CFO 对双链 DNA 中与 AOVP 相对的 8-氧鸟嘌呤具有反应性。我们通过高分辨率核磁共振分析了双链 DNA 中每个鸟嘌呤和 8-氧鸟嘌呤加合物的结构。结果表明,AOVP 与双链 DNA 中鸟嘌呤的 N2 氨基和 8-氧代鸟嘌呤的 N1 或 N2 氨基发生反应。这项研究首次证明了无需酶解即可直接测定双链 DNA 中的加合物结构。