Argonaute 2 Suppresses the Infection of Japanese Encephalitis Virus in Aedes aegypti.

Argonaute 2 Suppresses the Infection of Japanese Encephalitis Virus in Aedes aegypti. Jpn J Infect Dis. 2016 May 9; Authors: Sasaki T, Kuwata R, Hoshino K, Isawa H, Sawabe K, Kobayashi M Abstract There are mainly three innate immunity mechanisms against viruses in mosquitoes. Infection by the flavivirus dengue virus is controlled by RNAi, the JAK-STAT, and Toll signaling pathways. Our studies of another flavivirus, Japanese encephalitis virus (JEV), showed that the virus was not highly infectious for the salivary glands of Aedes aegypti and that viral resistance may be mediated by innate immunity. Argonaute 2 (Ago2) plays a critical role in the RNA interference (RNAi) pathway. To further determine the mechanism of viral resistance, we focused on Ago2 as a potential target of JEV. We show here that the expression of MyD88 (a mediator of Toll signaling) and Ago2 mRNAs were induced by JEV in the salivary glands of A. aegypti mosquitoes and that Ago2, JAK, and domeless (DOME) mRNAs were induced by JEV in carcasses of A. aegypti mosquitoes. Double-stranded (ds) Ago2 RNA enhanced JEV infection, and immunofluorescence assays detected virus in the salivary glands. In contrast, MyD88 dsRNA had no effect on JEV infection. These data suggest that Ago2 plays a crucial role in mediating the innate immunity of A. aegypti to JEV in a manner similar to that employed by dengue virus. PMID: 27169949 [PubMed - as supplied by publisher]
Source: Japanese Journal of Infectious Diseases - Category: Infectious Diseases Authors: Tags: Jpn J Infect Dis Source Type: research