E. Subcellular fractions of MEFs treated with 20 μM Dfo for 12 h, 10 μg/ml FAC for 12 h, or 100 μM Deferoxamine (Dfo) for 6 h after treatment with 10 μg/ml FAC for 12 h were prepared by differential centrifugation as described in (D). Each fraction was subjected to SDS-PAGE and analyzed by immunoblotting with the indicated antibodies. 