Quantitative Modeling of GRK-Mediated β2AR Regulation
Figure 7
Basis for “Cellular Memory” in the β2AR signaling machinery.
(A) Simulation of activation of β2AR by paired pulses of 1 µM ISO. Higher desensitization is obtained for the second and third pulse. Colors indicate simulated receptor species as indicated in the figure. (B) Decay in memory of prior stimuli on increase in inter-pulse period from 1–120 min. (C) Effect of up to 50 fold increase in surface dephosphorylation rates on memory of prior stimuli. Default dephosphorylation rate is 0.036/min. (D) Effect of arrestin-β2AR complex stability on desensitization time courses simulated by varying arrestin dissociation rates from the ligand-free complex on the surface. Default arrestin surface dissociation rate from the ligand-free complex is 10/min.