Beal P A, Dervan P B
Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena 91125.
Nucleic Acids Res. 1992 Jun 11;20(11):2773-6. doi: 10.1093/nar/20.11.2773.
The influence of sixteen base triplet changes at a single position within a pur.pur.pyr triple helix was examined by affinity cleaving. For the 15 base pair target site studied here, G.GC, A.AT and T.AT triplets stabilize a triple helix to a greater extent than the other 13 natural triplets (pH = 7.4, 25 degrees C). Weaker interactions were detected for the C.AT, A.GC and T.CG triplets. The absence of specific, highly stabilizing interactions between third strand bases and the CG or TA base pairs demonstrates a current sequence limitation to formation of this structure. Models for the two dimensional base triplet interactions for all possible 16 natural triplets are presented.
通过亲和切割研究了嘌呤-嘌呤-嘧啶三链螺旋内单个位置的16种碱基三联体变化的影响。对于此处研究的15个碱基对靶位点，G.GC、A.AT和T.AT三联体比其他13种天然三联体更能稳定三链螺旋（pH = 7.4，25℃）。检测到C.AT、A.GC和T.CG三联体的相互作用较弱。第三条链碱基与CG或TA碱基对之间不存在特异性的、高度稳定的相互作用，这表明目前该结构形成存在序列限制。给出了所有16种天然三联体的二维碱基三联体相互作用模型。
