Fig. 5. Co-transfection of normal and mutant opsin leads to the recruitment of the normal protein to the mutant opsin aggresome. (A) GFP-tagged WT opsin in pEGFP was co-transfected with untagged WT opsin in pMT3 (WT-GFP/WT-opsin) at a vector ratio of 1:10. Cells showed no increase in aggresome formation compared with WT-GFP alone, whereas co-transfection of GFP-tagged WT opsin in pEGFP with untagged P23H opsin in pMT3 (WT-GFP/P23H-opsin) at a vector ratio of 1:10 increased the percentage of WT opsin recruited to aggresomes, as judged by GFP fluorescence. Bar, 10 µm. (B) Quantification of co-transfection aggresome formation after 24 hours of opsin expression. The percentage of cells with WT-GFP fluorescence aggresomes was counted double blindly from four separate experiments (error bars±2 s.d.). BFA (20 µg/ml for 15 minutes prior to fixation) was added to both experiments to reduce confusion over WT opsin in the secretory pathway.