Figure 2. Agonist-induced internalization of sst₂ and sst₅ tail-swap mutants.

(A) Stably transfected HEK293 cells were treated with 1 µM SS-14 for 0, 15 or 30 min. Cells were then fixed, stained with the anti-sst₂ {UMB-1} or anti-sst₅ antibody {UMB-4} and examined by confocal microscopy. Shown are representative images from one of at least three independent experiments. Scale bar, 20 µm. (B) Stably transfected HEK293 cells were treated for 30 min with 1 µM SS-14. Receptor sequestration was measured by ELISA. Data represent per cent internalization of cell-surface receptors in SS-14-treated cells. Data are presented as mean ± SEM from at least three independent experiments performed in quadruplicate.