Sequence-specific delivery of a quinone methide intermediate to the major groove of DNA.
Sequence-specific delivery of a quinone methide intermediate to the major groove of DNA.
复制标题
将醌甲基化物中间体序列特异性递送至 DNA 大沟。
DOI：
10.1016/s0968-0896(01)00151-1
复制
发表时间：
2001
影响因子：
3.5
通讯作者：
Rokita,SE
中科院分区：
文献类型：
--
作者：
Zhou,Q;Pande,P;Johnson,AE;Rokita,SE
甲硅烷基保护的苯酚衍生物作为方便的前体，用于在生物条件下产生高度亲电的醌甲基化物中间体。反应是通过添加氟化物开始的，并且先前已经表现出在DNA烷基化和交联方面的熟练程度。这种方法现在已经扩展到通过三链体识别和氟依赖性醌甲基化物诱导来修饰双链体DNA。模型双链体的两种寡核苷酸通过与三链体缔合一致的寡核苷酸缀合物以序列特异性方式烷基化。最佳反应需要两个互补靶序列的存在和低于6.5的pH。此外，一个鸟嘌呤在每个链相邻的三链体区域的主要位点的烷基化。修饰的产率从富含嘌呤的链的约20%变化到富含嘧啶的链的仅4%。这种令人惊讶的差异表明，识别和反应性元件之间的接头可能会限制醌甲基化物和DNA的反应性亲核试剂之间的有效相互作用。该中间体的受限取向也可能是缺乏可检测水平的靶交联的原因。
Silyl-protected phenol derivatives serve as convenient precursors for generating highly electrophilic quinone methide intermediates under biological conditions. Reaction is initiated by addition of fluoride and has previously exhibited proficiency in DNA alkylation and cross-linking. This approach has now been extended to the modification of duplex DNA through triplex recognition and fluoride-dependent quinone methide induction. Both oligonucleotides of a model duplex were alkylated in a sequence specific manner by an oligonucleotide conjugate that is consistent with triplex association. Optimum reaction required the presence of the two complementary target sequences and a pH of below 6.5. In addition, one guanine in each strand adjacent to the triplex region was the predominant site of alkylation. The yield of modification varied from approximately 20% for the purine-rich strand to only 4% for the pyrimidine-rich strand. This surprising difference indicates that the linker between the recognition and reactive elements may limit productive interaction between the quinone methide and the reactive nucleophiles of DNA. Restricted orientation of this intermediate may also be responsible for the lack of target cross-linking at detectable levels.