Carrera P, Azorín F
Departament de Biologia Molecular i Cellular, Centre d'Investigació i Desenvolupament-CSIC, Barcelona, Spain.
Nucleic Acids Res. 1994 Sep 11;22(18):3671-80. doi: 10.1093/nar/22.18.3671.
AT-rich DNA sequences other than AnTm tracts (n + m > or = 4) are known to be intrinsically curved. The AATAT-element constitutes one known example of these sequences. In this paper, the elucidation of the structural basis of the curvature induced by this sequence element was addressed. As judged by the patterns of cleavage by the hydroxyl radical and DNase I, the AATAT sequence shows a narrow minor groove. Furthermore, the 5' adenine residue of the AA dinucleotide contained within the sequence is hyperreactive to diethylpyrocarbonate. Similar structural properties are shown by several sequences inducing intrinsic DNA curvature, such as an A5-tract or the closely related ATAAT, AATATA and TAATAT sequences, which are also shown here to induce curvature. On the other hand, other related sequences, such as TATAA and ATATA, that do not induce curvature, show different structural characteristics.
除了AnTm片段（n + m≥4）之外，富含AT的DNA序列已知具有内在弯曲性。AATAT元件就是这些序列中的一个已知例子。在本文中，探讨了由该序列元件诱导的弯曲的结构基础。根据羟基自由基和DNase I的切割模式判断，AATAT序列显示出狭窄的小沟。此外，该序列中AA二核苷酸的5'腺嘌呤残基对焦碳酸二乙酯具有高反应性。几个诱导DNA内在弯曲的序列也表现出类似的结构特性，例如一个A5片段或密切相关的ATAAT、AATATA和TAATAT序列，本文也表明它们会诱导弯曲。另一方面，其他不诱导弯曲的相关序列，如TATAA和ATATA，则表现出不同的结构特征。
