Runkel L, Nordheim A
Nucleic Acids Res. 1986 Sep 25;14(18):7143-58. doi: 10.1093/nar/14.18.7143.
A sequence of 86 bp within the 5' region of the adult chicken beta-globin gene was found to undergo a DNA conformational transition at elevated levels of negative superhelical stress (- sigma = 0.068). In vitro chemical DNA modification studies which detect purine hyperreactivity (HR) to the alkylating agent diethyl pyrocarbonate (DEP) have identified this 86 bp long DEP-HR element. The DEP-HR element is composed of small, tandem segments with imperfect purine-pyrimidine alternations. Methylation of cytosines within GCGC sequences of the DEP-HR element facilitates this structural change. The binding of a monoclonal anti-Z-DNA antibody to the element has been revealed by chemical footprinting with DEP. These data suggest that the DEP-HR sequence can undergo a conformational transition to Z-DNA. It is unknown whether the conformational flexibility observed here occurs in vivo.
在成年鸡β-珠蛋白基因5'区域内的一段86bp序列，发现在负超螺旋应力水平升高（-σ = 0.068）时会发生DNA构象转变。检测对烷基化剂焦碳酸二乙酯（DEP）的嘌呤高反应性（HR）的体外化学DNA修饰研究，已鉴定出这个86bp长的DEP-HR元件。DEP-HR元件由具有不完全嘌呤-嘧啶交替的小的串联片段组成。DEP-HR元件的GCGC序列内的胞嘧啶甲基化促进了这种结构变化。通过DEP化学足迹法揭示了单克隆抗Z-DNA抗体与该元件的结合。这些数据表明DEP-HR序列可以发生向Z-DNA的构象转变。这里观察到的构象灵活性是否在体内发生尚不清楚。
