Western blot analysis of total Myc and Myc:Max complexes during induced differentiation of U-937-myc-6 cells. (A) Early kinetics of TPA- and TPA + IFN-γ–stimulation for the times indicated. (B) Late kinetics of TPA- and/or IFN-γ–stimulation. Upper panels: analysis of total Myc expression. (A) v- plus c-Myc and (B) v-Myc were immunoprecipitated from low stringency lysates by rabbit pan-Myc antibodies (IG-13) or rabbit chicken Myc-specific antibodies (5042), respectively, followed by Western analysis using monoclonal pan-Myc antibodies (C-33). Middle and lower panels: analysis of Myc:Max complexes and Max expression, respectively. Aliquots of the same lysates as in the upper panels were immunoprecipitated by using C17 Max antibodies followed by Western analysis of coimmunoprecipitated Myc (middle panel) and of Max (lower panel). Equal amounts of protein were immunoprecipitated for each lane. The figure shows representative results from 1 of 4 independent experiments.