[Synthesis of virus-specific RNA in cells infected with influenza B virus]

Abstract

Synthesis of virus-specific RNA in cells infected with influenza B virus was studied by means of PAGE analysis of RNA hybrid duplexes or nucleocapsid-associated RNA. A switch from an "early" to "late" pattern was registered in the relative rates of synthesis of the corresponding mRNA as well as in the synthesis of vRNA segments 7 and 8. Contrary to the pattern described earlier for influenza A virus, the relative rate of synthesis of mRNA 5 was increased at the late stage of the replication cycle; besides, the efficiency of transcription of the polymerase genes was higher. Partial suppression of protein synthesis with moderate concentration of cycloheximide at a late stage of infection resulted in a differential inhibition of vRNA segments synthesis and stimulation of mRNA synthesis, leading to restoration of an "early" pattern in both cases. The results confirm the general outline of regulation as presented for influenza A virus in an earlier publication and reveal several peculiarities in regulation of influenza B viral RNA synthesis.