RNA interference in Nilaparvata lugens (Homoptera: Delphacidae) based on dsRNA ingestion

BACKGROUND: An efficient and convenient RNA interference (RNAi) technique involving double-stranded RNA (dsRNA) ingestion is useful for gene function studies of non-model insects. RESULTS: Three dsRNAs targeting different sites within a gene encoding vacuolar ATP synthase subunit E (V-ATPase-E, 21E01) were synthesised for RNAi in Nilaparvata lugens. dsRNA was found to be stable in 0.1 g mL(-1) sucrose solution, but unstable in artificial fodder. Therefore, dsRNAs were orally delivered into N. lugens in 0.1 g mL(-1) sucrose solution. RNAi was induced by all three of the dsRNAs at 0.05 mu g mu L-1 in N. lugens. Time dynamics analysis of gene silencing indicated that significant suppression of the target gene began as early as 2 days after ingestion of ds2-21E01 and ds3-21E01. However, significant repressive effects were recorded up to 10 days after exposure to ds1-21E01. The maximum reduction in target gene mRNA was observed after 10 days of treatment, with suppression ratios induced by ds1-21E01, ds2-21E01 and ds3-21E01 of 41,S and 48% respectively. CONCLUSION: An efficient and convenient RNAi technique involving dsRNA ingestion has been successfully developed for N. lugens. This will be a useful tool for further functional genomic investigation in this organism. (C) 2011 Society of Chemical Industry