Cooperative enhancement of translation by two adjacent microRNA-122/Argonaute 2 complexes binding to the 5′ untranslated region of hepatitis C virus RNA Nieder-Röhrmann, Anika and Dünnes, Nadia and Gerresheim, Gesche K and Shalamova, Lyudmila A and Herchenröther, Andreas and Niepmann, Michael,, 98, 212-224 (2017), doi = https://doi.org/10.1099/jgv.0.000697, publicationName = Microbiology Society, issn = 0022-1317, abstract= The liver-specific microRNA-122 (miR-122) binds to two conserved binding sites in the 5′ UTR of hepatitis C virus (HCV) RNA. This binding was reported to enhance HCV RNA replication, translation and stability. We have analysed binding of miR-122/Argonaute 2 (Ago2) complexes to these sites using anti-Ago2 co-immunoprecipitation of radioactively labelled HCV RNAs along with ectopic miR-122 in HeLa cells. Our results show that the miR-122 target sites can be addressed separately. When both target sites were addressed simultaneously, we observed a synergistic binding of both miR/Ago2 complexes. Consistently, simultaneous binding of both miR-122/Ago2 complexes results in cooperative translation stimulation. In the binding assays as well as in the translation assays, binding site 1 has a stronger effect than binding site 2. We also analysed the overall RNA stability as well as the 5′ end integrity of these HCV RNAs in the presence of miR-122. Surprisingly, using short HCV reporter RNAs, we did not find effects of miR-122 binding on overall RNA stability or 5′ end integrity over up to 36 h. In contrast, using full-length HCV genomes that are incapable of replication, we found a positive influence of miR-122 on RNA stability, indicating that features of the full-length HCV genome that do not reside in the 5′ and 3′ UTRs may render HCV RNA genome stability miR-122 dependent., language=, type=