ISGylation of viral protein NS1 Authored: Garapati, P V, 2011-01-18 EC Number: 6.3.2.19 Edited: Garapati, P V, 2011-01-18 Pubmed20133869 Pubmed20219937 Pubmed20385878 Reactome Database ID Release 431169395 Reactome, http://www.reactome.org ReactomeREACT_115965 Reviewed: Zhang, DE, 2011--0-2- Some viral proteins are also targeted for ISGylation. The well studied viral protein ISGylation is the modification of the influenza A viral protein NS1, which functions as an IFN antagonist during viral infection. Studies identified seven lysine residues in NS1 as potential ISGylation sites among which K41 (Zhao et al. 2010), K126 and K217 (Tang et al. 2010) were found to be critical. ISGylation at these sites disrupts NS1 association with importin-alpha, a protein required for the nuclear import of NS1. ISG15 E3 ligases ISG15:UBCH8:ISG15 E3 ligase ISGylated NS1