Fig. 3. P2Y₂R-mediated Rho activation and stress fiber formation require v integrin activity. Human 1321N1 cells expressing the WT P2Y₂R were incubated overnight at 37°C in serum-free medium with 10 µg/ml anti-v5 or anti-3 antibody. Cells were then treated with or without 100 µM UTP for 5 minutes before analysis of Rho activity (A) or 30 minutes before analysis of stress fiber formation (B). (A) Representative blots from three experiments are shown. (B) More than 100 cells were examined in three separate experiments and representative images are shown. Bar, 50 µm.