IBV NP

Influenzavirus B is a genus in the virus family Orthomyxoviridae. The only species in this genus is called Influenza B virus. The Influenza B virus capsid is enveloped while its virion consists of an envelope, a matrix protein, a nucleoprotein complex, a nucleocapsid, and a polymerase complex. It is sometimes spherical and sometimes filamentous. Its 500 or so surface projections are made of hemagglutinin and neuraminidase. Influenza virus nucleoprotein (NP) is a structural protein which encapsidates the negative strand viral RNA. NP is one of the main determinants of species specificity.