(A) The indicated SSTR3 constructs, all containing C-terminal EGFP, were expressed in IMCD3 cells and analyzed by immunofluorescence with antibodies against EGFP (green), ARL13B (red) and γ-tubulin (γTub, magenta). Cells were also stained with DAPI (DNA). All six constructs clearly reach the plasma membrane. (A, B) Indicated constructs were analyzed as in (A). IC3-mut1+CT-D335-428 mutant, lacking all but the first 10 residues in SSTR3-CT, consistently accumulates intracellularly and fails to reach plasma and ciliary membranes (left panels). In contrast, CT-mut1+IC3-D5, despite its intracellular retention frequency being much higher than normal (middle panels and Fig 7K), can still reach ciliary and/or plasma membrane in about 60% of transfected cells (right panels). Scale bars, 5 μm.