Fig. 2. Mutant opsin does not accumulate in the Golgi. Cells expressing WT (WT-GFP) and mutant (P23H-GFP) opsin tagged with GFP were treated with BFA (20 µg/ml for 15 minutes prior to fixation). BFA dispersed the Golgi (ß-COP) and the WT-GFP opsin that was trafficking through the Golgi but did not disperse the P23H-GFP opsin from its juxtanuclear position. Bar, 10 µm.