FIG. 5.

Effect of altered Gag/Gag-Pol ratios on packaging of genomic RNA. Three types of HIV-1 virions were used in this analysis; they were wild-type HIV-1 (WT), Pr-defective immature HIV-1 [PR(−)], and virions containing mainly monomeric RNA [WT:GP PR(−) (20:21)]. Supernatant collected from cells expressing only Gag-Pol precursor protein was also used as a control. Quantitation of pelleted viral protein was performed by protein dot immunoblot assay (A). Samples for RNA analysis (B and C) were standardized for protein concentration (A). Virion RNA encapsidation efficiency of wild-type and mutant viruses was analyzed by RNA dot blot hybridization assay (B). A series of 10-fold dilutions was done for quantitation. The stability of the virion-packaged RNA genome was determined by Northern blot analysis (see Materials and Methods for details of procedures) (C).