Fig. 4.
The region between G418 and N419 in the CB1 receptor was critical for GRK3- and β-arr2-mediated CB1 receptor desensitization. A, Schematic of the rat CB1 receptor.Short vertical lines indicate the sites of truncation or deletion. Representative traces show that truncation mutant Δ418 and deletion mutant (Δ418–439) eliminated GRK3- and β-arr2-mediated desensitization. B, Summary of data. Data were collected from at least three separate experiments with three different oocyte donors. C, Concentration response curves of WIN in wild-type CB1 receptor and mutant (ΔG418). Cumulatively increasing concentrations of WIN were applied to the bath followed by perfusion with SR 141716A. Oocytes were injected with cRNA for Kir3.1 and Kir3.4 and CB1 receptors. Each pointrepresents the mean response measured in seven oocytes.wt, Wild type.