Representative western blot images and quantifications of phospho-IRS1 (Y612, indicated by arrowhead) and AKT (T308, indicated by arrowhead) to GAPDH in wt and RHEB-Q64L L6 cells stimulated with insulin (100 nM, 5 min) after iron treatment (250 µM, 24 h). *P < 0.05 (multiple unpaired Student's t-test versus Basal in wt and RHEB Q64L cells) 