Fig. 5. Effect of thapsigargin on the localization of ricin B-chain. MDCK II cells grown on coverslips were incubated for 30 minutes at 37°C in the absence (A-C) or presence of 1 µg/ml thapsigargin (D-F). Then CY3-labeled ricin B-chain (1 µg/ml) (red) was added, and the incubation continued for 2 hours. The Golgi apparatus was labeled with sheep anti-human TGN46 antibodies followed by donkey anti-sheep/goat IgG FITC (green). C and F represent the merged images.