FIG. 1.
NC-mediated incorporation of ALIX into VLP. (A) Schematic illustration of the domain organizations of the HIV-1 Gag precursor (Pr55) and of mutant Gag molecules. A wavy line at the N terminus indicates the presence of a myristylation signal, and a gray box indicates the presence of a GCN4 zipper (Z) domain in place of NC-p1. (B) The ALIX binding site in p6 is not essential for the incorporation of ALIX into VLP. 293T cells were transfected with HIV-1 proviral DNA (5 μg) expressing no Gag, WT Gag, or C-terminally truncated Gag, along with 5 μg of a vector expressing ALIX-HA. VLP pellets and the cell lysates were analyzed by Western blotting to detect Gag and ALIX-HA as indicated. (C) The uptake of ALIX in the absence of the binding site in p6 depends on NC-p1. 293T cells were transfected with HIV-1 proviral DNAs (5 μg) expressing Gag molecules with a leucine zipper in place of NC-p1, along with 5 μg of a vector expressing ALIX-HA.