Blocking HSV-1 glycoprotein K binding to signal peptide peptidase reduces virus infectivity in vitro and in vivo
Fig 2
gK4 peptide inhibits the binding of gK protein to SPP protein.
A) Blocking gK binding to SPP. HEK293 cells were co-transfected with Flag-gK and HA-SPP plasmids. Cells were harvested 48 hr after transfection. Cell lysate was incubated with the indicated peptide for 2 hr at 4°C. IP using anti-Flag antibody in the presence of 5 μg/ml of indicated peptide recovered similar amounts of Flag-gK protein, but significantly less HA-SPP was recovered in the presence of peptide 4. B) Mutated form of gK4 does not precipitate SPP. HEK293 cells were transfected with HA-SPP and Flag-gK or Flag-gK mutant (amino acid RCIYA was mutated to AAAAA). Cell lysates were immunoprecipitated using anti-Flag antibody. The Flag-gK4 mutant failed to pull down HA-SPP, indicating the importance of the mutated region for gK binding to SPP. Panels: A) Mapping gK binding region to SPP; and B) Fine mapping of gK4 binding to SPP.