Department of Combinatorial Chemistry, Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine, Kyiv, Ukraine.
J Fluoresc. 2011 Jan;21(1):223-30. doi: 10.1007/s10895-010-0709-y. Epub 2010 Sep 1.
Two of earlier reported dsDNA sensitive cyanine dyes-monomethine Cyan 40 and meso-substituted trimethine Cyan 2 were studied for their ability to interact with non-canonical DNA conformations. These dyes were characterized by spectral-luminescent methods in the presence of G-quadruplex, triplex and dsDNA motifs. We have demonstrated that Cyan 2 binds strongly and preferentially to triple- and quadruple-stranded DNA forms that results in a strong enhancement of the dye fluorescence, as compared to dsDNA, while Cyan 40 form fluorescent complexes preferentially only with the triplex form. Highly fluorescent complexes of Cyan 2 with DNA triplexes and G-quadruplexes and Cyan 40 with DNA triplexes are very stable and do not dissociate during gel electrophoresis, leading to preferential staining of the above DNA forms in gels. The data presented point to the intercalation mechanism of the Cyan 2 binding to G4-DNA, while the complexes of Cyan 40 and Cyan 2 with triplex DNA are believed to be formed via groove binding mode. The Cyan dyes can provide a highly sensitive method for detection and quantification of non-canonical structures in genome.
我们研究了两种先前报道的 dsDNA 敏感的菁染料——单甲川菁 40 和中取代的三甲川菁 2，以研究它们与非规范 DNA 构象相互作用的能力。这些染料通过光谱发光方法在 G-四链体、三链体和 dsDNA 基序存在的情况下进行了表征。我们已经证明，Cyan 2 强烈且优先结合于三链体和四链体 DNA 形式，与 dsDNA 相比，这导致染料荧光的强烈增强，而 Cyan 40 仅优先与三链体形式形成荧光配合物。Cyan 2 与 DNA 三链体和 G-四链体以及 Cyan 40 与 DNA 三链体的高荧光配合物非常稳定，在凝胶电泳过程中不会解离，导致上述 DNA 形式在凝胶中优先染色。所提出的数据表明 Cyan 2 与 G4-DNA 的结合是嵌入机制，而 Cyan 40 和 Cyan 2 与三链体 DNA 的配合物则被认为是通过沟结合模式形成的。Cyan 染料可以为检测和定量基因组中非规范结构提供一种高度敏感的方法。
