(a) Ba/F3 cells expressing FOXO3(A3)-ER were stimulated with 4-OHT and actinomycin D (1 μg ml−1) or dimethylsulphoxide (DMSO) as a control in the presence of mIL-3 for 16 h. Cell lysates were analysed for protein levels of glutamine synthetase (GS), p27 and actin. Shown are representative blots (n=3). 