The bulk of the phosphorylation of human respiratory syncytial virus phosphoprotein is not essential but modulates viral RNA transcription and replication

The ability of variants of the human respiratory syncytial virus (HRSV) pho sphoprotein (P protein) to support RNA transcription and replication has be en studied by using HRSV-based subgenomic replicons. The serine residues no rmally phosphorylated in P during HRSV infection have been replaced by othe r residues. The results indicate that the bulk of phosphorylation of P (98% ) is not essential for viral RNA transcription or replication but that phos phorylation can modulate these processes.