Figure 6.

Cointernalization of GIPC with the D₂R, D₃R but not the D₄R. HEK/GIPC cells were transiently transfected with mycD₂R (A), mycD₃R (B), and GFPD₄R (C) cDNAs and stimulated by quinpirole (LY), a D₂-like agonist (2 μM for D₂R and D₃R, and 5 μM for D₄R) for 1 h. The anti-myc antibody was added on living cells, which were subsequently fixed, permeabilized, and incubated with the anti-Xpress antibody. Anti-myc and Xpress antibodies were revealed with secondary antibodies coupled to Alexa488 and CY3, respectively, the D₄R was detected by the GFP fluorescence and visualized by confocal microscopy.