As a consequence, influenzaNS1 gene knockout virus delNS1 (an influenza A virus lacking the NS1 open reading frame) fails to replicate in normal cells but produces infectious particles in PKR-deficient cells.
This phenomenon occurs with multiple strains of IAV, is dependent on influenzaNS1 protein, and can be modulated by SUMOylation of an intrinsically disordered region (IDR) of NS1 expressed by the 1918 pandemic IAV strain.
NS1 mutations D189N and V194I impaired the ability of the NS1 protein to inhibit general gene expression, and recombinant viruses harboring these mutations were attenuated in a mouse model of influenza infection.
Large-scale sequence analyses of influenza viruses revealed that nonstructural 1 (NS1) proteins from avian influenza viruses have a conserved C-terminal ESEV amino acid motif, while NS1 proteins from typical human influenza viruses have a C-terminal RSKV motif.
We designed six primers targeting the matrix genes of influenza H1 and H3 and the NS1 gene of influenza B and developed a M-LAMP assay using a commercially available Master Mix and a real time fluorometer (Genie II, Optigene, UK) that displays real time amplification, time to positivity and amplicon annealing temperature (Tm).
We propose that NS1 protein of both H5N1 and H11N1 subtypes of influenza viruses are capable of influencing host immune responses and possess necessary functionality to support apoptosis in host cells.
Nonstructural protein 1 (NS1) proteins from avian influenza viruses like the 1918 pandemic NS1 are capable of inhibiting the key signaling integrator c-Abl (Abl1), resulting in massive cytopathic cell alterations.
The NS1 proteins of most avian influenza viruses bear the C-terminal ligand sequence Glu-Ser-Glu-Val (ESEV) for PDZ domains present in multiple host proteins, whereas no such motif is found in the NS1 homologues of seasonal human virus strains.