Figure 4: Iron-mediated rescue of cell proliferation is independent of signaling and metabolite changes associated with lysosomal acidity.
(A) Comparison of metabolite abundance in 293T whole cells or purified lysosomes upon treatment with BafAl (10nM) in the presence or absence of iron supplementation (FAC 0.4 mg/ml). (Lysosomes r= 0.996, p<0.001; Whole cell r=0.785, P<0.001)
(B) Iron release from transferrin depends on lysosomal acidity. 293T lysates following uptake of biotinylated-holotransferrin, after 24-hour control, BafA1(10nM), or BafAl and FAC (0.1mg/ml) treatments were immobilized on PDVF membranes. Immunoblotting for TF, TFRC, and vinculin loading controls or incubation of membrane with HRP-streptavidin
(C) Immunoblotting for LC3B-II accumulation as an indicator of inhibition of autophagy completion in cells grown under BafA1 (10nM) or FAC (0.4mg/ml) for 24 hours.