tetano
Editor, Senior Moderator
J Gen Virol. 2015 Apr 15. pii: vir.0.000143. doi: 10.1099/vir.0.000143. [Epub ahead of print]
[h=1]The 20 amino acids at the C-terminus of PA-X are associated with increased influenza A virus replication and pathogenicity.[/h] Gao H[SUP]1[/SUP], Sun H[SUP]1[/SUP], Hu J[SUP]2[/SUP], Qi L[SUP]1[/SUP], Wang J[SUP]1[/SUP], Xiong X[SUP]1[/SUP], Wang Y[SUP]1[/SUP], He Q[SUP]1[/SUP], Lin Y[SUP]1[/SUP], Kong W[SUP]1[/SUP], Seng LG[SUP]3[/SUP], Pu J[SUP]1[/SUP], Chang KC[SUP]3[/SUP], Liu X[SUP]2[/SUP], Liu J[SUP]1[/SUP], Sun Y[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] The PA-X protein, arising from ribosomal frame-shift during PA translation, was recently discovered in influenza A virus. The C-terminal domain "X" of PA-X proteins in influenza A viruses can be classified as full length (61 amino acids) or truncated (41 amino acids). In the main, avian influenza viruses express full length PA-X proteins, while 2009 pandemic H1N1 (pH1N1) influenza viruses harbor truncated PA proteins. The truncated form lacks amino acids 232-252 of the full length PA-X protein. The significance of PA-X length in virus function remains unclear. To address this issue, we constructed a set of contemporary influenza viruses (pH1N1, avian H5N1 and H9N2) with full and truncated PA-X by reverse genetics to compare their replication and host pathogenicity. All full length PA-X viruses in human A549 cells conferred 10-100 fold increase in viral replication and 5-8% increase in apoptosis relative to corresponding truncated PA-X viruses. Full length PA-X viruses were more virulent and caused more severe inflammatory responses in mice. Furthermore, amino acids 233-252 at the C-terminus of PA-X strongly suppressed co-transfected gene expression by around 50%, suggesting that these terminal 20 amino acids could play a role in enhancing viral replication and contribute to virulence.
PMID: 25877935 [PubMed - as supplied by publisher]
[h=1]The 20 amino acids at the C-terminus of PA-X are associated with increased influenza A virus replication and pathogenicity.[/h] Gao H[SUP]1[/SUP], Sun H[SUP]1[/SUP], Hu J[SUP]2[/SUP], Qi L[SUP]1[/SUP], Wang J[SUP]1[/SUP], Xiong X[SUP]1[/SUP], Wang Y[SUP]1[/SUP], He Q[SUP]1[/SUP], Lin Y[SUP]1[/SUP], Kong W[SUP]1[/SUP], Seng LG[SUP]3[/SUP], Pu J[SUP]1[/SUP], Chang KC[SUP]3[/SUP], Liu X[SUP]2[/SUP], Liu J[SUP]1[/SUP], Sun Y[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] The PA-X protein, arising from ribosomal frame-shift during PA translation, was recently discovered in influenza A virus. The C-terminal domain "X" of PA-X proteins in influenza A viruses can be classified as full length (61 amino acids) or truncated (41 amino acids). In the main, avian influenza viruses express full length PA-X proteins, while 2009 pandemic H1N1 (pH1N1) influenza viruses harbor truncated PA proteins. The truncated form lacks amino acids 232-252 of the full length PA-X protein. The significance of PA-X length in virus function remains unclear. To address this issue, we constructed a set of contemporary influenza viruses (pH1N1, avian H5N1 and H9N2) with full and truncated PA-X by reverse genetics to compare their replication and host pathogenicity. All full length PA-X viruses in human A549 cells conferred 10-100 fold increase in viral replication and 5-8% increase in apoptosis relative to corresponding truncated PA-X viruses. Full length PA-X viruses were more virulent and caused more severe inflammatory responses in mice. Furthermore, amino acids 233-252 at the C-terminus of PA-X strongly suppressed co-transfected gene expression by around 50%, suggesting that these terminal 20 amino acids could play a role in enhancing viral replication and contribute to virulence.
PMID: 25877935 [PubMed - as supplied by publisher]