miR-122 and Ago interactions with the HCV genome alter the structure of the viral 5 terminus
miR-122 and Ago interactions with the HCV genome alter the structure of the viral 5 terminus
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DOI：
10.1093/nar/gkz194
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发表时间：
2019-06-04
影响因子：
14.9
通讯作者：
Sagan, Selena M.
中科院分区：
文献类型：
--
作者：
Chahal, Jasmin;Gebert, Luca F. R.;Sagan, Selena M.
丙型肝炎病毒（HCV）是一种与肝脏特异性microRNA（miR-122）相互作用的正义RNA病毒。miR-122与5个非翻译区（UTR）中的两个位点结合，这种相互作用促进HCV RNA积累，尽管miR-122在HCV生命周期中的确切作用仍不清楚。使用生物物理分析和通过引物延伸（SHAPE）分析的选择性2羟基酰化，我们研究了miR-122与5个UTR的相互作用。我们的数据表明，miR-122结合导致核苷酸1-117的改变，以抑制替代二级结构并促进功能性内部核糖体进入位点（IRES）的形成。此外，我们证明了两个hAgo 2：miR-122复合物能够同时结合到HCV 5末端，并且SHAPE分析揭示了5 UTR结构的进一步改变以容纳这些复合物。最后，我们提出了一个计算模型的hAgo 2：miR-122：HCV RNA复合物在5端的病毒基因组，以及hAgo 2：miR-122与IRES-40 S复合物的相互作用，表明hAgo 2很可能形成额外的相互作用与SLII，这可能进一步稳定HCV IRES。综上所述，我们的结果支持hAgo 2：miR-122复合物改变病毒5端结构并促进HCV IRES形成的模型。
Hepatitis C virus (HCV) is a positive-sense RNA virus that interacts with the liver-specific microRNA, miR-122. miR-122 binds to two sites in the 5 untranslated region (UTR) and this interaction promotes HCV RNA accumulation, although the precise role of miR-122 in the HCV life cycle remains unclear. Using biophysical analyses and Selective 2 Hydroxyl Acylation analyzed by Primer Extension (SHAPE) we investigated miR-122 interactions with the 5 UTR. Our data suggests that miR-122 binding results in alteration of nucleotides 1-117 to suppress an alternative secondary structure and promote functional internal ribosomal entry site (IRES) formation. Furthermore, we demonstrate that two hAgo2:miR-122 complexes are able to bind to the HCV 5 terminus simultaneously and SHAPE analyses revealed further alterations to the structure of the 5 UTR to accommodate these complexes. Finally, we present a computational model of the hAgo2:miR-122:HCV RNA complex at the 5 terminus of the viral genome as well as hAgo2:miR-122 interactions with the IRES-40S complex that suggest hAgo2 is likely to form additional interactions with SLII which may further stabilize the HCV IRES. Taken together, our results support a model whereby hAgo2:miR-122 complexes alter the structure of the viral 5 terminus and promote formation of the HCV IRES.