(c) Ba/F3 cells expressing myrPI(3) K-ER were cytokine-starved overnight. The next day, cells were washed in PBS and put in a medium without serum, with or without 4-OHT. At the times indicated, medium samples were taken and analysed for amino acid levels by high-performance liquid chromatography. Cells were lysed and equal amounts of protein were analysed by western blotting for levels of phospho-PKB (S473), phospho-FOXO3 (T32) and actin (inset). Shown are the mean of relative amino acid levels, compared with t=0 (n=2), and representative blots of these experiments. 