FIG. 4.

Analysis of wild-type and mutant HIV-1 virions. (A) Virus production in the culture medium after transfection of C33A cells with the proviral constructs. The results of three independent transfection experiments are summarized. Virus production for the wild-type (wt) pLAI construct was arbitrarily set at 1. (B) Packaging of HIV-1 RNA in virus particles. The packaging efficiency was measured by extension of the poly(A) primer on virion-isolated vRNA (Fig. 5, lanes 1 to 6). The results of three independent assays were quantitated, and the CA-p24 values were used to control for the amount of virions used per sample. Packaging was arbitrarily set at 1 for the wild-type virus.