Fig. 2. ERK1/2 and Rho activation mediated by WT and AAA mutant P2Y₂Rs. Human 1321N1 cells were transiently transfected with either WT (RGD) or AAA mutant P2Y₂Rs in pcDNA3.1(–). Transfected cells were starved overnight and stimulated with the indicated concentration of UTP for 5 minutes prior to measuring ERK1/2 phosphorylation (A) or Rho activity (B). (A) UTP-induced with 1 mM UTP for 5 minutes before measuring ERK1/2 phosphorylation is expressed as fold increase over basal level in cells transfected with WT P2Y₂R. Data points represent the mean ± s.e.m. of results from three experiments. (B) The Rho-GTP band density was normalized to total Rho and relative intensities are shown below each band as mean ± s.e.m. of results from four experiments.