21047957
not annotated - annotated - LINNAEUS only
Modification of nonstructural protein 1 of influenza A virus by SUMO1.
Nonstructural protein 1 (NS1) is one of the major factors resulting in the efficient infection rate and high level of virulence of influenza A virus. Although consisting of only approximately 230 amino acids, NS1 has the ability to interfere with several systems of the host viral defense. In the present study, we demonstrate that NS1 of the highly pathogenic avian influenza A/Duck/Hubei/L-1/2004 (H5N1) virus interacts with human Ubc9, which is the E2 conjugating enzyme for sumoylation, and we show that SUMO1 is conjugated to H5N1 NS1 in both transfected and infected cells. Furthermore, two lysine residues in the C terminus of NS1 were identified as SUMO1 acceptor sites. When the SUMO1 acceptor sites were removed by mutation, NS1 underwent rapid degradation. Studies of different influenza A virus strains of human and avian origin showed that the majority of viruses possess an NS1 protein that is modified by SUMO1, except for the recently emerged swine-origin influenza A virus (S-OIV) (H1N1). Interestingly, growth of a sumoylation-deficient WSN virus mutant was retarded compared to that of wild-type virus. Together, these results indicate that sumoylation enhances NS1 stability and thus promotes rapid growth of influenza A virus.
Ann file
T1 Species 43 60 influenza A virus
N1 Reference T1 Taxonomy:11320
T2 Species 203 220 influenza A virus
N2 Reference T2 Taxonomy:11320
T4 Species 439 483 influenza A/Duck/Hubei/L-1/2004 (H5N1) virus
N4 Reference T4 Taxonomy:11320
T5 Species 499 504 human
N5 Reference T5 Taxonomy:9606
T6 Species 603 607 H5N1
N6 Reference T6 Taxonomy:11320
T7 Species 861 878 influenza A virus
N7 Reference T7 Taxonomy:11320
T8 Species 890 895 human
N8 Reference T8 Taxonomy:9606
T9 Species 1031 1061;1071 1075 swine-origin influenza A virus H1N1
N9 Reference T9 Taxonomy:11320
T10 Species 1301 1318 influenza A virus
N10 Reference T10 Taxonomy:11320
T3 Species 1063 1068;1071 1075 S-OIV H1N1
N3 Reference T3 Taxonomy:11320