FIG. 6.

Analysis of GP_2a, GP₃, and GP₄ released into the medium of BHK-21 cells. (A) Immunoprecipitation of the GP₃ protein from the medium of BHK-21 cells infected with SFV-ORF3. Cells were pulse-chase labeled as described in the legend to Fig. 4A. Immunoprecipitates were treated with EndoH (H) or left untreated (U). (B) Immunoprecipitation of the GP₃ protein from the cell lysate (Lys) and medium of BHK-21 cells infected with SFV-ORF3. The cells were pulse-labeled, followed by a chase of 300 min. Immunoprecipitates were treated with PNGase F (F) or left untreated (U). (C) Immunoprecipitation of GP_2a, GP₃, and GP₄ proteins from the medium of BHK-21 cells coinfected with SFV-ORF2a, SFV-ORF3, and SFV-ORF4. At 4 h p.i., the cells were pulse-labeled, followed by a chase of 300 min. The medium was harvested, and the GP_2a, GP₃, and GP₄ proteins were subjected to immunoprecipitation with anti-GP_2a (α-GP_2a), anti-GP₃ (α-GP₃), or anti-GP₄ (α-GP₄) antibodies. Precipitates were either treated with PNGaseF (F) or left untreated (U). The arrows indicate the respective proteins.