STAT2 and viral infectious disease: To investigate STAT2 Y690 phosphorylation (pSTAT2Y690) induced by viral infections, we performed a time course study in which levels of pSTAT2Y690 were examined in cells infected with various strains of IAV such as WSN, PR8, CA04, H9N2, another RNA virus, Muscovy duck reovirus (MDRV), and also DNA virus such as Pseudorabies virus (PRV).