Identification and characterization of the novel antiviral gene rogue in Drosophila melanogaster. Jessica Tang^1,2, Anne Macgregor^1,3, Louisa Wu^1,3. 1) Institute for Bioscience and Biotechnology Research,; 2) Molecular and Cell Biology Graduate Program,; 3) Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD.

   Drosophila melanogaster has a robust and efficient antiviral innate immune system. For example, RNA interference (RNAi) is a general antiviral immune response. The three evolutionarily conserved signaling pathways: Toll, Imd and JAK-STAT are shown to defend against certain viruses. Autophagy is shown to play a role in immune response in Drosophila as well. Given the complexity of antiviral immunity in Drosophila, additional factors are likely to be involved. With the goal to discover novel antiviral genes, a pilot screen for mutants with increased susceptibility to a dsRNA virus Drosophila X Virus (DXV) was done, and four mutants were identified. One of the mutants, rogue, was mapped to an uncharacterized novel gene (rogue). Knockdown of rogue by RNAi in the whole animal or in specific tissues (hemocytes or fat-body) results in higher mortality after DXV infection compared to wildtype. Characterization of these rogue knockdown flies has revealed that although they are able to activate the Toll, Imd and JAK-STAT pathways, the transcript levels of some immune related genes are altered in the whole flies. Taken together, our results indicate that rogue is vital for defense against DXV and may be a novel factor that regulates the immune system in Drosophila. Identification and characterization of the antiviral gene rogue may provide new insight into how the immune system responds to viral infection.