Konno Keisuke, Fujita Syusuke, Iizuka Mana, Nishikawa Satoshi, Hasegawa Tsunemi, Fukuda Kotaro
Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan.
Nucleic Acids Symp Ser (Oxf). 2008(52):493-4. doi: 10.1093/nass/nrn250.
The minus-IRES ((-)IRES), corresponding to the 3'-terminal end of the negative strand of hepatitis C virus (HCV) RNA, is well conserved among HCV subtypes. The higher order structure of (-)IRES is essential for HCV replication, because the viral RNA dependent RNA polymerase, NS5B, recognizes it as the initiation site for plus-strand synthesis of the HCV genome. To inhibit the "de novo" synthesis of plus-strand RNA molecules, we performed an in vitro selection procedure for RNA aptamers that are specific for (-)IRES domain I. Among the selected aptamers, one RNA aptamer had two binding sites for the (-)IRES domain I. We found that this aptamer inhibited plus-strand synthesis by about 50%, suggesting that both binding sites are important for binding to its target within the (-)IRES domain I.
负内部核糖体进入位点（(-)IRES）对应于丙型肝炎病毒（HCV）RNA负链的3'末端，在HCV各亚型中高度保守。(-)IRES的高级结构对于HCV复制至关重要，因为病毒RNA依赖性RNA聚合酶NS5B将其识别为HCV基因组正链合成的起始位点。为了抑制正链RNA分子的“从头”合成，我们针对(-)IRES结构域I进行了RNA适体的体外筛选程序。在筛选出的适体中，一种RNA适体对(-)IRES结构域I有两个结合位点。我们发现这种适体可将正链合成抑制约50%，这表明两个结合位点对于在(-)IRES结构域I内与其靶标结合都很重要。
