Influenza B virus Nucleoprotein (NP) Protein (Control)

Influenza B viruses are enveloped, negative-sense single-stranded viruses consisting of 8 genomic RNA segments that code for at least 11 viral proteins. These proteins comprise the polymerase subunits (PA, PB1 and PB2), non-structural protein (NS1), nuclear export protein (NEP), matrix protein (BM1), ion channel (BM2), surface glycoproteins (HA, NA and NB) and the nucleoprotein (NP) . NB is encoded in the same segment as NA (segment 6) and while it is the only protein unique to influenza B viruses, its function is not fully understood. A brief summary of the functions of influenza B proteins are given in the Figure.