(A) Mycobacterial infection triggers ferritin ubiquitination in J774A.1 macrophages. (B) Mycobacterial infection induces ferritin-UBE2O interaction in J774A.1 cells. (C) UBE2O KO is validated by immunoblotting (upper left panel). Loss of UBE2O enhances M. tuberculosis-–induced ferritin expression in J774A.1 macrophages. Immunoblot analysis of UBE2O protein (upper right panel); protein level was quantified by ImageJ (NIH) and normalized to respective actin (lower panels). (D) Indispensable role of UBE2O in ubiquitin-dependent ferritin degradation. (E) Residue serine 82 is required for UBE2O-dependent ferritin degradation. Immunoblot analysis of FTH1 and FTL1 proteins (upper panel); protein level was quantified by ImageJ and normalized to respective actin (lower panels). (F) Mutant UBE2O at serine 82 fails to interact with ferritin. (G) Inactivation of UBE2O reduces mycobacterial survival in macrophages. (H) Treatment with arsenic trioxide, a UBE2O inhibitor, restricts mycobacterial survival in alveolar macrophages. (I) Inhibitory effect of ATO on M. tuberculosis infection in mice. Bacterial burden was analyzed at day 28 after infection. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001.