FIGURE 7.

Classical PKCs positively regulate the degradation of FcγRIIa. Neutrophils (20 × 10⁶ cells/ml) were incubated in the presence or absence of Gö6976 (1 μm) for 10 min before FcγRIIa cross-linking at room temperature for the indicated times. A, whole cell lysates were probed by immunoblotting for FcγRIIa (CT10) and c-Cbl (loading control). The densitometric values of the CT10 immunoblots were normalized with respect to those of the corresponding values for c-Cbl. These data are representative of four independent experiments. B, FcγRIIa was immunoprecipitated, and immunoprecipitates were probed for ubiquitin as described under “Experimental Procedures.” These data are representative of three independent experiments. C, neutrophils (40 × 10⁶ cells/ml) were preincubated with 1 mm DFP for 10 min at room temperature before incubating with Gö6976 and cross-linking FcγRIIa at room temperature. Plasma membranes were prepared as described under “Experimental Procedures” and analyzed by immunoblotting for the presence of c-Cbl, CIN85, and flotillin-1 (loading control). The line graphs represent densitometric quantifications of the means of three independent experiments. WB, Western blot; IP, immunoprecipitation. Error bars, S.E.