Figure 6.

C1orf27 depletion inhibits the export of β₂-AR and D2R, but not EGFR, from the ER through the Golgi to the cell surface. A–C, effect of C1orf27 knockdown by siRNA on the ER–Golgi transport of β₂-AR (A), D2R (B), and EGFR (C) in RUSH assays in fixed cells. HeLa cells were transfected with individual receptor plasmids together with control or C1orf27 siRNA and fixed at 15 and 30 min after addition of biotin. Scale bars, 10 μm. D, quantitative data shown in A–C. E, effect of C1orf27 siRNA on the surface expression of α_2A-AR, β₂-AR, D2R, and EGFR as measured in BRET assays. The quantitative data are expressed as mean ± SE (n = 17–26 cells in three experiments in D and n = 3 in E). ∗p < 0.05 and ∗∗∗p < 0.001 versus control siRNA. α2A-AR, α2A-adrenergic receptor; β2-AR, β2-adrenergic receptor; BRET, bioluminescence resonance energy transfer; D2R, dopamine D2 receptor; EGF, epidermal growth factor; EGFR, EGF receptor; RUSH, retention using the selective hooks.