Broad-spectrum antiviral activity of RNA interference against four genotypes of Japanese encephalitis virus based on single microRNA polycistrons.
Japanese encephalitis virus (JEV), a neurotropic mosquito-borne flavivirus, causes acute viral encephalitis and neurologic disease with a high fatality rate in humans and a range of animals. Small interfering RNA (siRNA) is a powerful antiviral agent able to inhibit JEV replication. However, the high rate of genetic variability between JEV strains (of four confirmed genotypes, genotypes I, II, III and IV) hampers the broad-spectrum application of siRNAs, and mutations within the targeted sequences could facilitate JEV escape from RNA interference (RNAi)-mediated antiviral therapy. To improve the broad-spectrum application of siRNAs and prevent the generation of escape mutants, multiple siRNAs targeting conserved viral sequences need to be combined. In this study, using a siRNA expression vector based on the miR-155 backbone and promoted by RNA polymerase II, we initially identified nine siRNAs targeting highly conserved regions of seven JEV genes among strains of the four genotypes of JEV to effectively block the replication of the JEV vaccine strain SA14-14-2. Then, we constructed single microRNA-like polycistrons to simultaneously express these effective siRNAs under a single RNA polymerase II promoter. Finally, these single siRNAs or multiple siRNAs from the microRNA-like polycistrons showed effective anti-virus activity in genotype I and genotype III JEV wild type strains, which are the predominant genotypes of JEV in mainland China. The anti-JEV effect of these microRNA-like polycistrons was also predicted in other genotypes of JEV (genotypes II and IV), The inhibitory efficacy indicated that siRNAs×9 could theoretically inhibit the replication of JEV genotypes II and IV.
State Key Laboratory for Molecular Virology and Genetic Engineering, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
Zhiqiang
Z
Wu
Ying
Y
Xue
Bei
B
Wang
Jiang
J
Du
Qi
Q
Jin
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017124:Conserved Sequence; D006224:Cricetinae; D004664:Encephalitis Virus, Japanese / Q000235:genetics* / Q000276:immunology / Q000502:physiology; D017930:Genes, Reporter / Q000235:genetics; D005814:Genes, Viral / Q000235:genetics*; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism; D005838:Genotype; D035683:MicroRNAs / Q000235:genetics*; D017720:Molecular Epidemiology; D034622:RNA Interference; D012319:RNA Polymerase II / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D013045:Species Specificity; D014162:Transfection; D014613:Vaccines, Attenuated / Q000276:immunology; D014779:Virus Replication / Q000235:genetics
D035683:MicroRNAs; D034741:RNA, Small Interfering; D014613:Vaccines, Attenuated; D012319:RNA Polymerase II