FIGURE 6.

Both Akt inhibitor X and wortmannin impair TGF-β-induced Smad3 association with CBP. Mutu-I, Kem-I, and Sav-I cells were treated, respectively, with 0.05, 0.05, and 0.1 μm of wortmannin (Wort) (A and B), 10 μm of Akt inhibitor X (Akt inh X) (C and D), or 10 μm of SB-431542 (A–D) for 1 h, prior to incubation with 2 ng/ml of TGF-β1. The cell lysates were immunoprecipitated (IP) with Smad3 (A and C) or CBP (B and D) antibodies, respectively. The immunoprecipitates were immunoblotted with anti-Smad3 or anti-CBP antibodies as indicated. The membranes were then reprobed with anti-acetyllysine antibody.