Background: Influenza virus nucleoprotein (NP) is a major component of the ribonucleoprotein complex and is abundantly expressed during the course of infection. It is a structural protein which encapsidates the negative strand viral RNA and is essential for RNA transcription replication and packaging. From the nucleotide sequence NP
is consists of 560 amino acids with calculated molecular mass of 61770.
Post-translational modification: Late in virus-infected cells may be cleaved from a 56-kDa protein to a 53-kDa protein by a cellular caspase. This cleavage might be a marker for the onset of apoptosis in infected cells or have a specific function in virus host interaction.