FIG. 2.

gB-mediated signaling requires native structure. Prior to cell stimulation, gB (200 μg/ml) was denatured by heating to 70 or 94°C for 15 min, reduced by the presence of DTT (100 μg/ml) for 30 min at 37°C, or proteolytically digested with trypsin for 60 min at 37°C. As a control, cells were stimulated with BSA (500 μg/ml) under identical conditions. (B) The protein profiles for the heat-denatured and DTT-treated samples were determined by SDS-PAGE and immunoblotting with an antibody specific for an epitope on the carboxy-terminal domain. The positions of the dimeric (gB-D), monomeric (gB-M), carboxy-terminal (gB-C) fragments and the heat-induced aggregate (heat agg.) are indicated.