Fig. 2.

MoMuLV Gag protein is associated with detergent-resistant membrane of untransfected 293-gag-pol packaging cells. Cells treated without (A) or with (B) 0.03 mM cholesterol for 48 h were homogenized and sonicated. Postnuclear supernatants were treated with (w) or without (w/o) 0.5% Triton X-100 (TX100) on ice or at 37 °C before equilibrium flotation centrifugation. Fractions containing MoMuLV Gag protein were detected by immunoblotting. Fractions (1–9) represent the sucrose gradient (10–85.5%). Fraction 1 corresponds to the top and fraction 9 corresponds to the bottom.