IFNA1 and viral infectious disease: In rainbow trout, the recombinant proteins of the two intracellular forms of type I IFNs generated from a single IFN gene (belonging to the IFN-a subgroup) by alternative splicing have been shown to possess similar functions to the secreted IFN and are able to trigger Mx gene expression in a fibroblast cell line (RTG-2 cells) and protect cells against viral infection.