Generation of influenza transfectants using purified recombinant nucleocapsid protein

Affinity-purified type A influenza virus nucleocapsid protein expressed by a recombinant baculovirus vector was used in in vitro RNA transcription rea ctions to create RNP complexes containing a synthetic influenza A virus NS gene. When used in transfection assays, the baculovirus-expressed NP was sh own to be biologically active allowing the efficient isolation of transfect ant viruses containing the artificially-introduced NS gene. The results dem onstrate that NP is the only virion protein necessary in the reconstituted RNP complexes used for transfection thus eliminating the need for purified RNP complexes containing active polymerase. (C) 1998 Elsevier Science B.V. All rights reserved.