Fig. 1

Effects of Gag cleavage site mutations on virus assembly and processing. a Schematic representations of HIV-1 Gag and Gag-Pol expression constructs. Indicated are the HIV-1 Gag protein domains MA (matrix), CA (capsid), p2, NC (nucleocapsid), p1 and p6, and pol-encoded p6*, PR, RT and IN. Arrowheads indicate where alanines (A/A) were substituted for amino acid residues at the MA/CA (Y/P) and p2/NC (M/M) junctions. b-d Enhanced PR activation by efavirenz (EFV) reduced virus yields and Gag-Pol packaging. 293T cells were transfected with designated constructs. At 18 h post-transfection, transfectants were equally split, placed on two plates, and either treated or mock-treated with 1 µM EFV. At 4 h post-treatment, culture supernatants were removed and replaced with medium containing EFV with or without an HIV-1 protease inhibitor (panel d). Shown is a representative immunoblot from two independent experiments. Cells and supernatants were harvested for Western immunoblot analysis 48 h after medium replacement. HIV-1 Gag proteins were probed with anti-p24CA and anti-p17MA monoclonal antibodies. Anti-RT serum was used to detect RT. Indicated are positions of the RT p66 and p51 subunits, Pr55^gag, p4^1gag, p24^gag and p17^gag