Characterisation of an avian influenza virus nucleoprotein expressed inE. coli and in insect cells (original) (raw)

The nucleoprotein (NP) gene from influenza virus A/Shearwater/ Australia/72 has been expressed intracellularly in both E. coli and insect cells. E. col#derived NP was identified by Western blot analysis as a 56 kDa protein which co-migrates with virion-derived NP. This protein was purified by immunoaffinity chromatography and a nitrocellulose binding assay showed that NP formed complexes with positive-and negative-sense influenza neuraminidase RNA transcribed in vitro. ELISA and Western blot analysis revealed that recombinant NP of 56 kDa was produced in high yields in insect cells using a baculovirus vector. Immunofluorescence microscopy revealed that NP was localised to the nucleus of infected insect cells.