Project description:High throughput sequencing was performed using Illumina HiSeq to identify differentially regulated genes in Culex mosquitoes after West Nile virus infection.
Project description:RNA interference (RNAi) functions as a potent antiviral immunity in plants and invertebrates, however whether RNAi plays antiviral roles in mammals remains unclear. Here, using human enterovirus 71 (HEV71) as a model, we showed HEV71 3A protein as an authentic viral suppressor of RNAi during viral infection. When the 3A-mediated RNAi suppression was impaired, the mutant HEV71 readily triggered the production of abundant HEV71-derived small RNAs with canonical siRNA properties in cells and mice. These virus-derived siRNAs were produced from viral dsRNA replicative intermediates in a Dicer-dependent manner, loaded into AGO, and were fully active in degrading cognate viral RNAs. Recombinant HEV71 deficient in 3A-mediated RNAi suppression was significantly restricted in human somatic cells and mice, whereas Dicer-deficiency rescued HEV71 infection independently of type I interferon response. Thus, RNAi can function as an antiviral immunity, which is induced and suppressed by a human virus, in mammals.
Project description:Analysis of Culex quinquefasciatus responses to West Nile virus (WNV) infection at 7 and 14 days after ingestion of infected blood in the gut and carcass tissues.
Project description:Culex pipiens molestus and Cx. p. quinquefasciatus are the members of Culex pipiens Complex, but they display relatively large differences in behavior and physiological responses. We compared the genes of these mosquitoes to identify those that were differentially expressed in each subspecies. Such genes could play important roles in subspecies-specific blood feeding or oviposition behavior. Culex pipiens molestus and Cx. p. quinquefasciatus females were undertaken Illumina RNA sequencing.
Project description:Culex pipiens molestus and Cx. p. quinquefasciatus are the members of Culex pipiens Complex, but they display relatively large differences in behavior and physiological responses. We compared the genes of these mosquitoes to identify those that were differentially expressed in each subspecies. Such genes could play important roles in subspecies-specific blood feeding or oviposition behavior.
Project description:Analysis of Culex quinquefasciatus responses to West Nile virus (WNV) infection at 7 and 14 days after ingestion of infected blood in the gut and carcass tissues. Comparison of WNV-infected to non-infected carcass and gut samples.
Project description:Background: RNA silencing pathways play critical roles in gene regulation, virus infection, and transposon control. RNA interference (RNAi) is mediated by small interfering RNAs (siRNAs), which are liberated from double stranded (ds) RNA precursors by Dicer and direct the RNA-induced silencing complex (RISC) to target transcripts. Recent efforts have uncovered important principles governing small RNA (smRNA) sorting into RISC, yet mechanisms defining substrate selection by Dicer proteins remain uncharacterized. Methodology: To better characterize Dicer-2 substrates in Drosophila, we examined the antiviral RNAi response, which generates virus-derived siRNAs from viral RNA. Using high-throughput sequencing, we found that diverse viruses were uniquely targeted; substrates included dsRNA replication intermediates and intramolecular RNA stem loops. smRNA distribution patterns from viral and synthetic dsRNA precursors were highly reproducible, and machine learning techniques identified characteristics of precursor molecules and smRNA duplexes important in determining relative smRNA abundance. Significance: To our knowledge, this study provides the first description of the rules governing Dicer-2 substrate selection, which has important implications for exogenous RNA silencing technologies and the development of smRNA-based antiviral therapeutics. virus-derived siRNA (vsiRNA) expression comparison between control and 4 different virus-infected cells in control as well as 5 different RNAi pathway protein knock-downs in Drosophila dl1 cells