FIGURE 8.

p53 regulates Akt and GSK3β phosphorylation via effects on Aha1 and Hsp90. A and B, cells were treated with LY294002 as indicated for 24 h. C and H, EB-1 cells were treated with indicated concentrations of ZnCl₂ for 6 h. D, cells were transfected with 2 μg of Aha1 siRNA or control siRNA for 48 h. E, cells were treated with the indicated concentrations of 17-AAG for 0.5 h. F, cells were transfected with 2 μg of control siRNA or Akt1 siRNA for 48 h. G, cells were transfected with 2 μg of control siRNA or p53 siRNA for 48 h. I, cells were treated with indicated concentration of CP-31398 for 6 h. J, cells were transfected with 2 μg of control siRNA or Aha1 siRNA for 48 h. K, cells were treated as indicated with 1.0 μm 17-AAG for 0.5 h. A–K, cell lysates were subjected to Western blot analysis. The blots were probed as indicated. L, p53 regulates Aha1 levels leading to altered Hsp90 ATPase activity. This results in modulation of the Akt/GSK3β signaling axis and thereby the expression of Wnt target genes.