UC Riverside

RNA interference (RNAi) refers to specific gene silencing by double-stranded RNA (dsRNA)-induced RNA degradation, it directs specific antiviral immunity in fungi, plants, insects and nematodes. In plants, antiviral RNAi is systemic; however, in animals the results are inconclusive. In this dissertation, I found that a class of systemic RNAi related genes including RSD-2, RSD-3 and RSD-6 were required in antiviral immunity of Caenorhabditis elegans using Flock house Virus (FHV) replicon. But another class like SID-1 and RSD-4 were not required. This result was confirmed by Orsay virus infection. Moreover, though sid-1 and rsd-4 single mutants were still resistant to Orsay virus infection, in double mutants of rsd-2;sid-1 and rsd-3;sid-1 the losses of antiviral immunity from single mutations have additive effect. This research provides evidence of the antiviral role of C. elegans systemic RNAi.