Scholten P M, Nordheim A
Nucleic Acids Res. 1986 May 27;14(10):3981-93. doi: 10.1093/nar/14.10.3981.
Two palindromic DNA sequences were analyzed with respect to their chemical reactivities with diethyl pyrocarbonate. In negatively supercoiled plasmid templates enhanced N7 carbethoxylation was found with individual purines located in presumptive single-stranded loops of DNA cruciform structures. No enhanced reactivity at these positions was observed in linear, relaxed or low superhelical density plasmids. Hyperreactivity was found over a narrow region only, indicating that stable cruciforms contain loops of minimal size. No enhanced chemical reactivity was found with the four-way junction at the base of cruciforms. Diethyl pyrocarbonate has proved a sensitive structural probe for the analysis, with single nucleotide resolution, of DNA cruciform structures.
对两个回文DNA序列进行了分析，研究它们与焦碳酸二乙酯的化学反应性。在负超螺旋质粒模板中，位于DNA十字形结构假定单链环中的个别嘌呤出现了增强的N7乙氧基化。在线性、松弛或低超螺旋密度的质粒中，这些位置未观察到增强的反应性。超反应性仅在一个狭窄区域被发现，这表明稳定的十字形结构包含最小尺寸的环。在十字形结构底部的四向连接处未发现增强的化学反应性。焦碳酸二乙酯已被证明是一种用于以单核苷酸分辨率分析DNA十字形结构的灵敏结构探针。
