Viral RNA modifications play important roles in interactions with the immune system of host cells. The mA modification of viral RNAs allows for the viruses to escape recognition by the retinoic acid inducible gene-I receptor (RIG-I), in the type 1 IFN response, a crucial pathway of innate immunity. 5' N-7methylguanisone capping and 2-O-methylation also play vital roles for the viral infections. The cap structures help viral RNA to blend in among modified cellular mRNA and avoid triggering immune response systems.