%0 Journal Article %A Shao, Qiang %A Xu, Wenping %A Guo, Qiang %A Yan, Li %A Rui, Lei %A Liu, Jinhua %A Zhao, Yaofeng %A Li, Zandong %T RIG-I from waterfowl and mammals differ in their abilities to induce antiviral responses against influenza A viruses %D 2015 %J Journal of General Virology, %V 96 %N 2 %P 277-287 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.069914-0 %I Microbiology Society, %X The retinoic acid-induced gene I (RIG-I) plays a crucial role in sensing viral RNA and IFN-β production. RIG-I varies in length and sequence between different species. We assessed the functional differences between RIG-I proteins derived from mammals and birds. The transfection of duck caspase recruitment domains (CARDs) and duck RIG-I (dCARDs and dRIG-I) and goose CARDs and goose RIG-I (gCARDs and gRIG-I) into chicken DF-1 cells increased the production of IFN-β mRNA and IFN-stimulated genes and decreased influenza A virus (IAV) replication; whereas human CARDs and RIG-I (hCARDs and hRIG-I) and mouse CARDs and RIG-I (mCARDs and mRIG-I) had no effect. In human 293T and A549 cells, hCARDs had the strongest IFN-inducing activity, followed by mCARDs, dCARDs and gCARDs. The IFN-inducing activity of hRIG-I was stronger than that of mRIG-I, dRIG-I and gRIG-I, in that order. The results showed that, although the ability of dCARDs to activate IFN was stronger than that of gCARDs in DF-1, 293T and A549 cells, dRIG-I had a weaker ability to activate IFN than gRIG-I in DF-1 cells with or without IAV infection. These data suggest that RIG-I proteins from different species have different amino acid sequences and functions. This genetic and functional diversity renders RIG-I flexible, adaptable and capable of recognizing many viruses in different species. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.069914-0