Fig. 3. Mitochondrial Lon chaperone activity contributes to the stability of ULK1 complex for the mitophagy activation.

A HCT-15 cells were transfected with the plasmids encoding pcDNA3-Lon in different concentrations (0.5–5 μg). Cell lysates were analyzed by immunoblotting using the indicated antibodies. GAPDH as the loading control. B HCT-15 cells were transfected with the plasmids encoding myc-Lon, myc-LonK529R (ATPase mutant), or myc-LonS855A (protease mutant). Cell lysates were analyzed by immunoblotting using the indicated antibodies. GAPDH as the loading control. C, D HCT-15 cells were transfected with the plasmids encoding empty, myc-Lon, or myc-LonK529R in the presence or absence of CoCl₂ treatment (200 μM for 18 h). Cell lysates were analyzed by immunoblotting using the indicated antibodies. GAPDH as the loading control. E HCT-15 cells transfected with the plasmids encoding Lon-shRNA or empty were treated with or without MG132 (10 μM for 6 h). Cell lysates were analyzed by immunoblotting using the indicated antibodies. GAPDH as the loading control. F HCT-15 cells transfected with the plasmids encoding Lon-shRNA or empty vector were treated with or without Cycloheximide (50 µg/mL) for the indicated time course. Cell lysates were analyzed by immunoblotting using the indicated antibodies. GAPDH as the loading control.