FIGURE 3.
G protein signaling is not changed in CB1R mutants. (a) C‐tail mutations do not significantly change acute CB1R mediated Gαi protein activation. HEK293 cells were transiently cotransfected with CB1R‐SNAP variant, Gαi‐Rluc8, Gβ‐Flag, Gγ‐YFP (2:1:1:1 ratio). Twenty‐four hours after transfection, 5 μM coelenterazine h was added, cells were stimulated with increasing concentrations of WIN and the decrease in BRET signal was measured 15 min after WIN application. (b) CB1R mutants retain the ability to cause IP1 release induced by WIN. HEK293 cells were transiently cotransfected with CB1R‐SNAP variant and chimeric G protein Gqi9. Twenty‐four hours after transfection, cells were stimulated with increasing concentrations of WIN. The extent of IP1 accumulation was measured 20 min after WIN application. Data represent the mean ± SEM of three experiments of independent cell preparations performed in three technical replicates. Data were normalized against the maximal WIN‐ induced response