FIGURE 3.

Regulation of βarrs by GPCR signaling barcodes. A–C, in the signaling barcode model, a receptor activated by ligand (A) recruits kinases and other enzymes that generate a signaling barcode (B) on the C-terminal tail of the receptor. This results in the recruitment of βarr and activation of effector molecules (C). D, changes to the barcode result in differential effector coupling by βarrs (shown are the clathrin adapter AP-2 and ERK MAPK). 7TMR, seven-transmembrane class of receptors; Ub, ubiquitin.