Figure 4.
D1 and CRF2α receptors form a stable heteromeric complex in HEK293T cells. (A) Co-localization of CRF2α receptorCFP with the plasma membrane marker WGA647, when it was co-expressed with: D1 receptorYFP (a–c), D1 receptor-NLSYFP (d–f) or D1 receptor-NLSYFP treated with SCH23390 (1 μM) (g–i). The number of CRF2α receptors in the plasma membrane was augmented when it was co-expressed with D1 receptorYFP (a–c). When co-transfected with D1 receptor-NLSYFP, the CRF2α receptorCFP co-trafficked with the D1 receptor-NLSYFP to the intracellular compartment, being excluded from the plasma membrane (d–f). The treatment with SCH23390 (1 μM) to the cells co-transfected with D1 receptor-NLSYFP and CRF2α receptorCFP allowed both receptors to be observed at the cell surface (g–i). (B) Pearson's correlation coefficient between CFP and WGA647. In each condition, the Pearson's coefficient was calculated from the different transfection conditions. Data are expressed as mean ± SEM and represent results from 18 to 30 cells of two independent experiments. (C) Quantification of the percentage of cells showing a surface phenotype for CRF2α receptors. The percentage of cells was calculated in the different transfection conditions. Data are expressed as mean ± SEM and represent results from about 200 cells from three independent experiments (n = 3) *P ≤ 0.05, Mann–Whitney test.