Fig. 6. GSK-3 activity is crucial for apoptosis in MDCK cystogenesis. (A) Wild-type MDCK cells were cultured on Matrigel (72 hours) and infected with Ad-LacZ, Ad-HA-GSK-3 (S9A), Ad-HA-GSK-3 (K85M) for 24 hours, or not infected (MDCK control). Immunostaining analysis was performed with HA (green), cleaved caspase-3 (red) and actin (white). Bar, 10 µm. (B) The percentage of cysts containing apoptotic cells was quantified by cleaved caspase-3 staining. Results are the mean±s.d. of three experiments. ^*P<0.05 compared with either Ad-LacZ or Ad-HA-GSK-3 (K85M). (C) MDCK cysts infected with Ad-LacZ, Ad-HA-GSK-3 (S9A), or Ad-HA-GSK-3 (K85M) were subjected to immunoblot with -gal (green), HA (red) and GAPDH (red).