Extended Data Figure 3. Pertussis toxin sensitivity of ERK1/2 activation by G_i/o-coupled GPCRs.

HEK293 cells transfected with the β₂AR, S1PR₁, or α_2AAR were serum-deprived overnight the presence or absence of 1ng/mL Bordetella pertussis toxin (PTX) prior to 5min stimulation with isoproterenol, S1P, or UK14303, respectively. Representative phospho-ERK1/2 immunoblots are shown above bar graphs depicting the mean +/− s.e.m. of independent biological replicates (n=5, β₂AR, S1P₁R and α_2AAR). Responses were normalized to the basal level of phospho-ERK1/2 in non-stimulated samples. * p<0.05, # p<0.005 less than stimulated response in the absence of pertussis toxin.