Inhibition of influenza virus replication by constrained peptides targetingnucleoprotein.

摘要

BACKGROUND: Because of high mutation rates, new drug-resistant viruses arerapidly evolving, thus making the necessary control of influenza virus infection difficult.METHODS: We screened a constrained cysteine-rich peptide library mimickingμ-conotoxins from Conus geographus and a proline-rich peptide library mimickinglebocin 1 and 2 from Bombyx mori by using influenza virus RNA polymerase (PB1,PB2 and PA) and nucleoprotein (NP) as baits.RESULTS: Among the 22 peptides selected from the libraries, we found that theNP-binding proline-rich peptide, PPWCCCSPMKRASPPPAQSDLPATPKCPP, inhibitedinfluenza replicon activity to mean±sd 40.7%±15.8% when expressed as a GFP fusionpeptide in replicon cells. Moreover, when the GFP fusion peptide was transducedinto cells by an HIV-TAT protein transduction domain sequence, the replication ofinfluenza virus A/WSN/33 (WSN) at a multiplicity of infection of 0.01 wasinhibited to 20% and 69% at 12 and 24 h post-infection, respectively. Inaddition, the TAT-GFP fusion peptide was able to slightly protect Balb/c micefrom WSN infection when administrated prior to the infection.CONCLUSIONS: These results suggest the potential of this peptide as the seed ofan anti-influenza drug and reveal the usefulness of the constrained peptidestrategy for generating inhibitors of influenza infection. The results alsosuggest that influenza NP, which is conserved among the influenza A viruses, is agood target for influenza inhibition, despite being the most abundant protein in infected cells.