Fig. 3
From: Quaternary structure of a G-protein-coupled receptor heterotetramer in complex with Gi and Gs
Gs and Gi coupling to adenosine A1R-A2AR heterocomplexes. Bioluminescence resonance energy transfer (BRET) experiments were performed in HEK-293T cells 48 h post-transfection with (a, b) 0.2 μg of cDNA corresponding to A1R and 0.15 μg of cDNA corresponding to A2AR; (c, d) 0.2 μg of cDNA corresponding to A1R or 0.15 μg of cDNA corresponding to A2AR and 0.4 μg of cDNA corresponding to growth hormone secretagogue receptor GHS1a; (e) 0.2 μg of cDNA corresponding to A1R; or (f) 0.15 μg of cDNA corresponding to A2AR. Cells were also transfected with 2 μg of cDNA corresponding to the α-subunit of Gi fused to Rluc and increasing amounts of cDNA corresponding to the α-subunit of Gs fused to YFP (a) or 0.3 μg of cDNA corresponding to the γ-subunit fused to Rluc and increasing amounts of cDNA corresponding to the γ-subunit fused to YFP (b–f). Maximum miliBRET unit (mBU) values are the mean ± standard error of the mean of four different experiments. A scheme showing the protein to which Rluc and YFP were fused is provided (top). ***p < 0.001 by one-way ANOVA with post - hoc Dunnett’s test