Expression of the PSMB4-GFP or GFP-PSMB4 reporters was induced for 18 h with dox. After removal of dox, cells were treated with 100 μg/mL CHX and 20 μM MG132 as indicated. Cell lysates were analyzed by native PAGE and in-gel fluorescence to detect GFP and RFP or denaturing SDS-PAGE followed by immunoblot for GFP. The ratio of unassembled GFP to RFP from native in-gel fluorescence was quantified from three independent experiments, normalized to the untreated sample (lane 1), and plotted below the gels. Statistical comparisons between key samples by Student’s t test are indicated:∗∗indicatesp< 0.01 and∗∗∗indicatesp< 0.001.
