(e) DLD1 cells expressing FOXO3(A3)-ER were transfected with glutamine synthetase (GS) siRNA or a non-targeting siRNA and stimulated with 4-OHT in glutamine-free DMEM containing 0.1% FBS. After 24 h, cell lysates were analysed for protein levels of glutamine synthetase, LC3 and actin. Shown are representative blots (n=2) 