FIGURE 9.

Depletion of Atg5 level partially protected the cells from exogenous cathepsin D-induced toxicity. A, immunoblot depicting Atg5 levels in mouse m5-7 fibroblast cells with or without doxycycline treatment. Note the reduction in Atg5 levels following doxycycline treatment. B, MTT assay showing that doxycycline-treated m5-7 cells are partially resistant to cathepsin D-induced toxicity compared with untreated m5-7 fibroblast cells. All results, which are presented as means ± S.E. (error bars), were obtained from three separate experiments. Ctrl, control. *, p < 0.05.