FIG. 6.

Coimmunoprecipitation of E2 proteins with E1. Sf9 cells were infected with 1 MOI of baculoviruses encoding either E1 or mutant E1F237L proteins and increasing MOIs of baculoviruses encoding either wild-type E2 or E2-A4 protein. At 48 h postinfection, the cells were lysed, and the extracts were incubated with monoclonal antibody BPV104 coupled to protein G-Sepharose. After three wash cycles, the E2 protein was eluted with 0.4% N-lauroylsarcosine and detected by Western blotting. After quantitation of the bands, the values were normalized for equal E1 protein concentration and plotted against the E1/E2 MOI ratio, with the value of the highest wild-type E1/E2 ratio set at 100%.