FIG. 1.

Association of HCV NS proteins with detergent-resistant membrane fractions. Huh7-replicon cells were harvested at 48 h after seeding. Huh7 cells were harvested 48 h after transfection with plasmids expressing individual NS proteins or infection with a recombinant adenovirus expressing NS3-NS5. Cell lysates were treated with 1% NP-40 for 1 h on ice or with 1% Triton X-100 for 1 h at 37°C and then fractionated by discontinuous sucrose gradient centrifugation as described in Materials and Methods. One-milliliter fractions were collected from top to bottom of the sucrose gradient, concentrated in YM-30 Centricons, and analyzed on polyacrylamide gels. The proteins were detected by immunoblotting with monoclonal antibodies to NS5A, NS5B, NS3, or Flag.