Fig 3. β-arrestin2^0K binding to receptors demonstrated by chemical cross-linking.

A. COS-7 cells transiently transfected with FLAG-β2AR with pEGFP vector or β-arrestin2^0K-GFP were stimulated with 10 μM isoproterenol for 5 min and FLAG receptors immunoprecipitated after chemical cross-linking with DTME. The IP was probed with a β-arrestin antibody (upper panel) and a receptor specific antibody, H-20 (lower panel). B. The bar graph represents quantification of β-arrestin2^0K in the IP from 5 independent experiments. *: p, 0.04 according to a paired t test.