The NS3 and NS4A genes as the targets of RNA interference inhibit replication of Japanese encephalitis virus in vitro and in vivo.

Abstract

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that can cause acute encephalitis with a high fatality rate. RNA interference (RNAi) is a powerful tool to silence gene expression and a potential therapy for virus infection. In this study, the antiviral ability of eight shRNA expression plasmids targeting different sites of the NS3 and NS4A genes of JEV was determined in BHK21 cells and mice. The pGP-NS3-3 and pGP-NS4A-4 suppressed 93.9% and 82.0% of JEV mRNA in cells, respectively. The virus titer in cells was reduced approximately 950-fold by pretreating with pGP-NS3-4, and 640-fold by pretreating with pGP-NS4A-4. The results of western blot and immunofluorescence analysis showed JEV E protein and viral load in cells were remarkably inhibited by shRNA expression plasmids. The viral load in brains of mice pretreated with pGP-NS3-4 or pGP-NS4A-4 were reduced approximately 2400-fold and 800-fold, respectively, and the survival rate of mice challenged with JEV were 70% and 50%, respectively. However, the antiviral ability of shRNA expression plasmids was decreased over time. This study indicates that RNAi targeting of the NS3 and NS4A genes of JEV can sufficiently inhibit the replication of JEV in vitro and in vivo, and NS3 and NS4A genes might be potential targets of molecular therapy for JEV infection.

• Authors: Lei Yuan, Rui Wu, Hanyang Liu, Xintian Wen, Xiaobo Huang, Yiping Wen, Xiaoping Ma, Qigui Yan, Yong Huang, Qin Zhao, Sanjie Cao
• Journal: Gene (Gene) Vol. 594 Issue 2 Pg. 183-189 (Dec 15 2016) ISSN: 1879-0038 [Electronic] Netherlands
• PMID: 27593564 (Publication Type: Journal Article)
• Copyright: Copyright © 2016 Elsevier B.V. All rights reserved.

Chemical References

• NS3 protein, flavivirus
• NS4A protein, flavivirus
• RNA, Small Interfering
• Viral Nonstructural Proteins
• Serine Endopeptidases
• RNA Helicases

Topics

• Animals
• Cell Line
• Cricetinae
• Encephalitis Virus, Japanese (physiology)
• Encephalitis, Japanese (genetics, metabolism, therapy)
• Gene Expression Regulation, Viral (genetics)
• Gene Targeting (methods)
• Mice
• RNA Helicases (antagonists & inhibitors, biosynthesis, genetics)
• RNA Interference
• RNA, Small Interfering (biosynthesis, genetics)
• Serine Endopeptidases (biosynthesis, genetics)
• Viral Nonstructural Proteins (antagonists & inhibitors, biosynthesis, genetics)
• Virus Replication (genetics)