tetano
Editor, Senior Moderator
J Virol. 2012 Jul 11. [Epub ahead of print]
Roles of the phosphorylation of specific serines and threonines in the NS1 protein of human influenza A viruses.
Hsiang TY, Zhou L, Krug RM.
Source
Department of Molecular Genetics and Microbiology, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas USA.
Abstract
We demonstrate that phosphorylation of the NS1 protein of a human influenza A virus occurs not only at the threonine (T) at position 215, but also at serines (Ss), specifically at positions 42 and 48. By generating recombinant influenza A/Udorn/72 (Ud) viruses that encode mutant NS1 proteins, we determined the roles of these phosphorylations in virus replication. At position 215 only a T-to-A substitution attenuated replication, whereas other substitutions had no effect: T-to-E to mimic constitutive phosphorylation; T-to-N; and T-to-P, the amino acid in avian influenza A virus NS1 proteins. We conclude that attenuation resulting from the T-to-A substitution at position 215 is attributable to a deleterious structural change in the NS1 protein that is not caused by other amino acid substitutions, and that phosphorylation of T215 does not affect virus replication. At position 48 neither a S-to-A substitution, nor a S-to-D substitution that mimics constitutive phosphorylation affected virus replication. In contrast, at position 42, a S-to-D, but not a S-to-A substitution caused attenuation. The S-to-D substitution eliminates detectable double-stranded RNA binding by the NS1 protein, accounting for attenuation of virus replication. We show that PKCα catalyzes S42 phosphorylation. Consequently, the only phosphorylation of the NS1 protein of this human influenza A virus that regulates its replication is S42 phosphorylation catalyzed by PKCα. In contrast, phosphorylation of Ts or Ss in the NS1 protein of the 2009 H1N1 pandemic virus is was not detected, indicating that NS1 phosphorylation probably does not play any role in the replication of this virus.
PMID:
22787231
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22787231
Roles of the phosphorylation of specific serines and threonines in the NS1 protein of human influenza A viruses.
Hsiang TY, Zhou L, Krug RM.
Source
Department of Molecular Genetics and Microbiology, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas USA.
Abstract
We demonstrate that phosphorylation of the NS1 protein of a human influenza A virus occurs not only at the threonine (T) at position 215, but also at serines (Ss), specifically at positions 42 and 48. By generating recombinant influenza A/Udorn/72 (Ud) viruses that encode mutant NS1 proteins, we determined the roles of these phosphorylations in virus replication. At position 215 only a T-to-A substitution attenuated replication, whereas other substitutions had no effect: T-to-E to mimic constitutive phosphorylation; T-to-N; and T-to-P, the amino acid in avian influenza A virus NS1 proteins. We conclude that attenuation resulting from the T-to-A substitution at position 215 is attributable to a deleterious structural change in the NS1 protein that is not caused by other amino acid substitutions, and that phosphorylation of T215 does not affect virus replication. At position 48 neither a S-to-A substitution, nor a S-to-D substitution that mimics constitutive phosphorylation affected virus replication. In contrast, at position 42, a S-to-D, but not a S-to-A substitution caused attenuation. The S-to-D substitution eliminates detectable double-stranded RNA binding by the NS1 protein, accounting for attenuation of virus replication. We show that PKCα catalyzes S42 phosphorylation. Consequently, the only phosphorylation of the NS1 protein of this human influenza A virus that regulates its replication is S42 phosphorylation catalyzed by PKCα. In contrast, phosphorylation of Ts or Ss in the NS1 protein of the 2009 H1N1 pandemic virus is was not detected, indicating that NS1 phosphorylation probably does not play any role in the replication of this virus.
PMID:
22787231
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22787231