Identification of a Novel Complex between the Nucleoprotein and PA(1-27) of Influenza A Virus Polymerase.

The structure of the ribonucleoprotein complexes is crucial to viral transcription and replication of influenza virus, but association of the nucleoprotein (NP) with the polymerase remains to be characterized at the molecular level. Here, we identify a peptide of the polymerase acidic subunit PA(1-27) that associates with NP. Docking and molecular dynamics simulations suggest a similar NP binding site with PA(1-27) and PA(1-186). The PA(1-27)-NP complex is characterized by surface plasmon resonance and fluorescence using recombinant NP proteins and by pull-down assays in infected cells. The PA(1-27)-NP complex may have a role in the final steps of transcription and replication.