FIG. 2.

Processing of Gag polyproteins in mutated and wild-type viruses as studied by gel analysis of samples that had been subjected to radiolabeling and immunoprecipitation. COS-7 cells were transfected with wild-type BH10 or with mutated viral DNA (BH10-LD3, BH10-LD4, and BH10-LD5), and they were radiolabeled with [³⁵S]Met and [³⁵S]Cys for 1 h thereafter. Cells were lysed at either 1 or 4 h after radiolabeling, and viral proteins in cell lysates were immunoprecipitated with immunoglobulin G monoclonal antibodies against the CA protein. (A) Time course experiments after the radiolabeling of COS-7 cells that had been transfected with wild-type BH10 DNA. The cells were lysed at 0, 10, 20, or 40 min or at 1 or 4 h after radiolabeling. (B to D) Results of studies performed with mutated BH10-LD3, BH10-LD4, and BH10-LD5, respectively. Mock-transfected COS-7 cells served as negative controls and underwent the radiolabeling and immunoprecipitation protocols described above. The relative density ratios of the CA (p24) and CA-p2 bands are shown at the bottoms of the gels.