Ushijima K, Gouzu H, Hosono K, Shirakawa M, Kagosima K, Takai K, Takaku H
Department of Industrial Chemistry, Chiba Institute of Technology, Japan.
Biochim Biophys Acta. 1998 Feb 2;1379(2):217-23. doi: 10.1016/s0304-4165(97)00101-3.
Sequence specific RNA cleaving molecules were synthesized by attaching novel polyamine derivatives bearing imidazole and/or primary amine groups to the 5'-end of DNA oligonucleotides as the sequence-recognizing moieties. The actions of the molecules on a half-tRNA(Asp) were investigated. The oligonucleotides directed the nuclease activity (the imidazole and the primary amine are the catalytic groups) of the enzyme to the nucleotides directly adjacent to the complementary target sequence on the substrate RNA. The cleavage reaction shows a bell-shaped pH dependence with a maximum at pH 7.0, indicating the participation of protonated and non-protonated imidazoles residues in the process. The specificity of these hybrid enzymes can be easily altered, and they should prove to be useful tools for probing RNA structures in solution and as potential reactive groups in antisense oligonucleotide derivatives. We also describe the site-specific cleavage of tRNA(Asp) by the cleaving reagents bearing imidazole and/or primary amine groups at the 5'-end of oligodeoxyribonucleotides.
通过将带有咪唑和/或伯胺基团的新型多胺衍生物连接到作为序列识别部分的DNA寡核苷酸的5'-末端，合成了序列特异性RNA切割分子。研究了这些分子对半tRNA（Asp）的作用。寡核苷酸将酶的核酸酶活性（咪唑和伯胺为催化基团）导向底物RNA上与互补靶序列直接相邻的核苷酸。切割反应呈现出钟形的pH依赖性，在pH 7.0时达到最大值，表明质子化和非质子化的咪唑残基参与了该过程。这些杂合酶的特异性可以很容易地改变，并且它们应该被证明是用于探测溶液中RNA结构以及作为反义寡核苷酸衍生物中潜在反应基团的有用工具。我们还描述了在寡脱氧核糖核苷酸5'-末端带有咪唑和/或伯胺基团的切割试剂对tRNA（Asp）进行的位点特异性切割。
