Bailly C, Colson P, Houssier C, Hamy F
Institut de Recherches sur le Cancer, INSERM Unité 124, Lille, France.
Nucleic Acids Res. 1996 Apr 15;24(8):1460-4. doi: 10.1093/nar/24.8.1460.
For the first time, the interaction between a series of small molecules and the TAR RNA of HIV-1 has been investigated by electric linear dichroism (ELD). The compounds tested include the DNA intercalating drugs proflavine and ethidium bromide and an amsacrine-4-carboxamide DNA-threading intercalator as well as the AT-specific DNA minor groove binders netropsin, Hoechst 33258, berenil and DAPI. In all cases except for netropsin, negative reduced dichroism signals were measured in the drug absorption band. In agreement with previous studies, the results indicate that both classical and threading intercalation can occur with the TAR RNA. The ELD data show that the mode of binding of the drugs Hoechst 33258, berenil and DAPI to the TAR RNA is similar to their binding mode in GC-rich regions of DNA and likely involves intercalation into the A-form TAR RNA helix. The wide and shallow minor groove of the TAR RNA is apparently not accessible to DNA minor groove binding drugs such as netropsin. The ELD technique appears uniquely valuable as a means of investigating the interaction of drugs with the TAR RNA.
首次通过电线性二色性（ELD）研究了一系列小分子与HIV-1的TAR RNA之间的相互作用。所测试的化合物包括DNA嵌入药物原黄素和溴化乙锭、一种安吖啶-4-羧酰胺DNA穿线嵌入剂，以及AT特异性DNA小沟结合剂纺锤菌素、Hoechst 33258、贝尼尔和DAPI。除纺锤菌素外，在所有情况下，均在药物吸收带中测得负的比二色性信号。与先前的研究一致，结果表明经典嵌入和穿线嵌入均可与TAR RNA发生。ELD数据表明，药物Hoechst 33258、贝尼尔和DAPI与TAR RNA的结合模式与其在富含GC的DNA区域中的结合模式相似，并且可能涉及嵌入A形式的TAR RNA螺旋中。TAR RNA宽而浅的小沟显然无法被诸如纺锤菌素之类的DNA小沟结合药物所接近。ELD技术作为研究药物与TAR RNA相互作用的一种手段，显得具有独特的价值。
