Fiorini Adriana, de Gouveia Fabiana Souza, de Soares Maria Albertina Miranda, Stocker Ann Jacob, Ciferri Ricardo Rodrigues, Fernandez Maria Aparecida
Departamento de Biologia Celular e Genética, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900, Maringá, Paraná, Brasil.
Mol Biol Rep. 2006 Mar;33(1):71-82. doi: 10.1007/s11033-006-0009-4.
Intrinsic bent DNA sites were identified in the 4289 bp segment encompassing the replication zone which directs DNA amplification and transcription of the C3-22 gene of Rhynchosciara americana. Restriction fragments showed reduced electrophoretic mobility in polyacrylamide gels. The 2D modeling of the 3D DNA path and the ENDS ratio values obtained from the dinucleotide wedge model of Trifonov revealed the presence of four major bent sites, positioned at nucleotides -6753, -5433, -5133 and -4757. Sequence analysis showed that these bends are composed of 2-6 bp dA.dT tracts in phase with the DNA helical repeat. The circular permutation analysis permitted the verification that the fragments containing the bending sites promote curvature in other sequence contexts. Computer analyses of the 4289 bp sequence revealed low helical stability (DeltaG values), negative roll angles indicating a narrow minor groove and a putative matrix attachment region. The data presented in this paper add to information about the structural features involved in this amplified segment.
在包含指导美洲大蠊C3 - 22基因DNA扩增和转录的复制区的4289 bp片段中鉴定出了内在弯曲的DNA位点。限制性片段在聚丙烯酰胺凝胶中显示出降低的电泳迁移率。三维DNA路径的二维建模以及从Trifonov的二核苷酸楔形模型获得的ENDS比值表明存在四个主要弯曲位点，位于核苷酸 - 6753、 - 5433、 - 5133和 - 4757处。序列分析表明，这些弯曲由与DNA螺旋重复序列同相的2 - 6 bp dA.dT序列组成。环形置换分析证实了含有弯曲位点的片段在其他序列背景下也能促进弯曲。对4289 bp序列的计算机分析显示出低螺旋稳定性（ΔG值）、指示窄小沟的负滚动角以及一个假定的基质附着区域。本文提供的数据增加了关于该扩增片段所涉及的结构特征的信息。
