Indeed, the activation of duck RIG-I in the absence of attached polyubiquitin chains may be a mechanism to evade viral subversion of ubiquitin pathways [23], such as NS1 from H5N1 avian influenza, which preferentially interacts with TRIM25 in chicken cells, and decreases IFN production [23], even in the absence of RIG-I [28]. This evidence concerns the gene RIGI and avian influenza.