Influenza virus NS1 protein interacts with the cellular 30 kDa subunit of CPSF and inhibits 3'end formation of cellular pre-mRNAs.
The mechanism by which influenza A virus nucleoprotein forms oligomers and binds RNA
The nucleoprotein structure shows that only one of two proposed nuclear localization signals are accessible, and suggests that the body domain of nucleop protein contains the binding site for the viral polymerase.
Influenza B virus NS1 protein inhibits conjugation of the interferon (IFN)‐induced ubiquitin‐like ISG15 protein
The novel way in which the function of the ISG15 protein is inhibited is demonstrated: a specific region of the influenza B virus NS1 protein, which includes part of its effector domain, blocks the covalent linkage ofISG15 to its target proteins both in vitro and in infected cells.
Influenza A virus NS1 protein targetspoly(A)‐binding protein II of the cellular 3′‐end processing machinery
In vitro assays suggest that the 30 kDa CPSF and PABII proteins bind to non‐overlapping regions of the NS1A protein effector domain and indicate that these two 3′ processing proteins also directly bind to each other.
The Influenza Viruses
- R. Krug
- 8 October 2011
Among the most significant accomplish ments in influenza virus research has been the delineation of the three dimensional structure of the two surface glycoproteins of the virus, the hemagglutinin and neuraminidase, which provided a structural basis for mapping both the antigenic sites and the regions involved in the major biological functions of these two molecules.
Human ISG15 conjugation targets both IFN-induced and constitutively expressed proteins functioning in diverse cellular pathways.
- Chen Zhao, C. Denison, J. Huibregtse, S. Gygi, R. Krug
- Biology, ChemistryProceedings of the National Academy of Sciences…
- 19 July 2005
Results indicate that ISG15 conjugation impacts nuclear as well as cytoplasmic functions and targeting a wide array of constitutively expressed proteins greatly extends the repertoire of cellular functions that are affected by IFN-alpha/beta.
Binding of the influenza virus NS1 protein to double-stranded RNA inhibits the activation of the protein kinase that phosphorylates the elF-2 translation initiation factor.
The NS1 protein of influenza A virus binds not only to poly(A) and a stem-bulge region in U6 small nuclear RNA (snRNA), but also to double-stranded RNA, and blocks the activation of the dsRNA-activated protein kinase (PKR) in vitro.
RNA binding by the novel helical domain of the influenza virus NS1 protein requires its dimer structure and a small number of specific basic amino acids.
- W. Wang, K. Riedel, P. Lynch, C. Chien, G. Montelione, R. Krug
- Biology, ChemistryRNA: A publication of the RNA Society
- 1 February 1999
Helix 2 and helix 2', which are antiparallel and next to each other in the dimer conformation, constitute the interaction face between the NS1 RNA-binding domain and its RNA targets, and that the arginine side chain at position 38 and possibly the lysine sidechain at position 41 in each of these antipar parallel helices contact the phosphate backbone of the RNA target.
Cellular antiviral responses against influenza A virus are countered at the posttranscriptional level by the viral NS1A protein via its binding to a cellular protein required for the 3' end…