FIG. 4.

Analysis of the effects of CT truncations on the detergent-resistant association of Env with immature HIV-1 particles. Immature viruses were pelleted though a layer of 0.5% Triton X-100 at 4°C to remove the viral membrane. (A) Pellets were dissolved, and proteins were analyzed by immunoblotting with antibodies to Gag, gp41, and CypA. (B) To quantify the detergent-resistant association of gp41 with immature particles, gp41 and Gag band signal intensities were quantified and the gp41/Gag ratios in detergent-treated and untreated samples were calculated for each virus. The results are expressed as a percentage of gp41 retention following detergent treatment of immature particles containing the wild-type Env protein. Results shown are the mean values and standard deviations obtained in three independent experiments.