INFLUENZA-VIRUS NS1 PROTEIN INTERACTS WITH VIRAL TRANSCRIPTION-REPLICATION COMPLEXES IN-VIVO

The interaction of influenza virus NS1 protein with other viral produc ts in the infected cell was analysed by co-immunoprecipitation studies . The three subunits of the polymerase and the nucleoprotein, but not M1 protein, were co-immunoprecipitated by NS1-specific serum but not w hen control serum was used. Such co-immunoprecipitation was not sensit ive to RNase treatment of the immunoprecipitates. Co-immunoprecipitati on was also obtained when the viral transcription-replication system w as reconstituted in vivo by transfection of cDNAs and model vRNA templ ate into vaccinia virus-T7-infected cells. Analysis of the RNA pulled- down in the NS1-specific precipitates indicated the presence of both v RNA and mRNA. These results are discussed in the context of the phenot ype of virus temperature-sensitive mutants affected in the NS1 gene.