FIG. 4.

BAD phosphorylation in 32D cells expressing the wild-type and mutant IGF-1 receptors. BAD phosphorylation was determined, as described in Materials and Methods, under three different sets of conditions, all in medium with 10% FBS: with IL-3, with IGF-1 (I), or with no additions. BAD phosphorylation was determined at 3 h after IL-3 withdrawal. The cell lines and the treatments are indicated above the BAD blots. In the case of the cell lines expressing IRS-1, the IR, or both, the FBS was supplemented with insulin (50 ng/ml). In all other cases, IGF-1 (50 ng/ml) was used. Under the BAD blots are Western blots of Grb2, used as indicators of protein amounts in each lane.