Fig. 6.

Inhibition of ATM does not prevent phosphorylation of AMPK and Akt by serum starvation. Differentiated cells were incubated in serum-containing or serum-free medium in the presence of 1 μM KU55933 or DMSO (vehicle) for 3 h before extraction in ice-cold lysis buffer. Cell lysates were subjected to SDS/PAGE and then Western blot analysis. A: P-AMPK and AMPK (n = 6/group). B: P-Akt S473 and Akt (n = 3/group). C: P-Akt T308 and Akt (n = 6/group). D: effects of serum starvation and KU55933 on p53 protein level (n = 12/group). *Significant difference due to serum starvation (P < 0.05); †effect of KU55933 (P < 0.05). Data represent means ± SE.