tetano
Editor, Senior Moderator
Virol J. 2012 Aug 21;9(1):167. [Epub ahead of print]
Influenza A H3N2 subtype virus NS1 protein targets into the nucleus and binds primarily via its C-terminal NLS2/NoLS to nucleolin and fibrillarin.
Mel?n K, Tynell J, Fagerlund R, Roussel P, Hermandez-Verdun D, Julkunen I.
Abstract
ABSTRACT:
BACKGROUND:
Influenza A virus non-structural protein 1 (NS1) is a virulence factor, which is targeted into the cell cytoplasm, nucleus and nucleolus. NS1 is a multi-functional protein that inhibits host cell pre-mRNA processing and counteracts host cell antiviral responses. Previously, we have shown that the NS1 protein of the H3N2 subtype influenza viruses possesses a C-terminal nuclear localization signal (NLS) that also functions as a nucleolar localization signal (NoLS) and targets the protein into the nucleolus.
RESULTS:
Here, we show that the NS1 protein of the human H3N2 virus subtype interacts in vitro primarily via its C-terminal NLS2/NoLS and to a minor extent via its N-terminal NLS1 with the nucleolar proteins, nucleolin and fibrillarin. Using chimeric green fluorescence protein (GFP)-NS1 fusion constructs, we show that the nucleolar retention of the NS1 protein is determined by its C-terminal NLS2/NoLS in vivo. Confocal laser microscopy analysis shows that the NS1 protein colocalizes with nucleolin in nucleoplasm and nucleolus and with B23 and fibrillarin in the nucleolus of influenza A/Udorn/72 virus-infected A549 cells. Since some viral proteins contain NoLSs, it is likely that viruses have evolved specific nucleolar functions.
CONCLUSION:
NS1 protein of the human H3N2 virus interacts primarily via the C-terminal NLS2/NoLS and to a minor extent via the N-terminal NLS1 with the main nucleolar proteins, nucleolin, B23 and fibrillarin.
PMID:
22909121
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/22909121
Influenza A H3N2 subtype virus NS1 protein targets into the nucleus and binds primarily via its C-terminal NLS2/NoLS to nucleolin and fibrillarin.
Mel?n K, Tynell J, Fagerlund R, Roussel P, Hermandez-Verdun D, Julkunen I.
Abstract
ABSTRACT:
BACKGROUND:
Influenza A virus non-structural protein 1 (NS1) is a virulence factor, which is targeted into the cell cytoplasm, nucleus and nucleolus. NS1 is a multi-functional protein that inhibits host cell pre-mRNA processing and counteracts host cell antiviral responses. Previously, we have shown that the NS1 protein of the H3N2 subtype influenza viruses possesses a C-terminal nuclear localization signal (NLS) that also functions as a nucleolar localization signal (NoLS) and targets the protein into the nucleolus.
RESULTS:
Here, we show that the NS1 protein of the human H3N2 virus subtype interacts in vitro primarily via its C-terminal NLS2/NoLS and to a minor extent via its N-terminal NLS1 with the nucleolar proteins, nucleolin and fibrillarin. Using chimeric green fluorescence protein (GFP)-NS1 fusion constructs, we show that the nucleolar retention of the NS1 protein is determined by its C-terminal NLS2/NoLS in vivo. Confocal laser microscopy analysis shows that the NS1 protein colocalizes with nucleolin in nucleoplasm and nucleolus and with B23 and fibrillarin in the nucleolus of influenza A/Udorn/72 virus-infected A549 cells. Since some viral proteins contain NoLSs, it is likely that viruses have evolved specific nucleolar functions.
CONCLUSION:
NS1 protein of the human H3N2 virus interacts primarily via the C-terminal NLS2/NoLS and to a minor extent via the N-terminal NLS1 with the main nucleolar proteins, nucleolin, B23 and fibrillarin.
PMID:
22909121
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/22909121