Inhibition of Dengue virus 2 replication by artificial micrornas targeting the conserved regions.

Dengue virus (DENV), a mosquito-borne flavivirus, causes serious diseases and threatens public health in tropical and subtropical areas worldwide. RNA interference (RNAi) is a prevailing strategy for antiviral therapy. In this paper, 6 single artificial microRNAs (amiRNAs) targeting the highly conserved regions of the DENV-2 genome were identified and inhibited virus replication efficiently. Then, effective tandem amiRNAs targeting 2 different DENV-2 genome regions were constructed and expressed simultaneously from a single microRNA-like polycistron to avoid virus variation or mutation escape. Finally, the most high-performance tandem amiRNA was embedded in a lenti-viral vector and inhibited DENV-2 virus replication stably and dose-dependently. Overall, these results indicated that RNAi based on multiple amiRNAs targeting viral conserved regions was an effective approach for improvements of nucleic acid inhibitors of DENV and provided a new therapeutic strategy for DENV infection in humans.