FIG. 2.

Effects of nocodazole and mimosine on Vpu activity. (A) Cells were grown to 25% confluence in the presence or absence of the cell cycle inhibitor nocodazole (NOC) (10 μg/ml). Cells were infected, transfected, and metabolically labeled as described in the text. Anti-p24 (CA) antiserum immunoprecipitates were analyzed by SDS-PAGE and densitometry, and the proportion of total Gag proteins found in the supernatants (Sup.) was determined. Error bars represent standard deviations for the experiment performed in triplicate. (B) Cells were grown to 25% confluence in isoleucine-deficient medium for 48 h. This medium was then replaced with complete medium containing 400 μM mimosine. After 48 h, treated cells and untreated cells, also plated at 25% confluence, were transfected, labeled, and analyzed by immunoprecipitation and SDS-PAGE as described in the text.