Figure 3.

GOPC is required for glucose-stimulated insulin secretion. (A) Western blot analysis of isolated islets from Arfrp1^flox/flox and Arfrp1^{β-cell−/−} mice probed with indicated antibodies. (B) Immunofluorescent pictures of dispersed islet cells from Arfrp1^flox/flox and Arfrp1^{β-cell−/−} mice stained with indicated antibodies. Nuclei were visualized with DAPI. Scale bar represents 20 μm. (C) Quantification of glucose-stimulated insulin secretion from Min6 cells treated with indicated adenoviruses with a MOI of 50. Data from 3 independent experiments measured in duplicates is shown as mean ± SEM. ∗p < 0.05 (2-way ANOVA). (D) 3D-rendering after structured illumination microscopy of Ins1 cells under basal (2.8 mM glucose) and stimulated (20 mM glucose) conditions stained for GOPC (green) and ARFRP1 (white). White lines outline the 3-dimensional box containing the immunolabeled proteins. Inner box size = 3.5 ∗ 3.5 μm. (E) Nearest neighbor (N/N) distances between surfaces of stained objects (GOPC and ARFRP1) were calculated from SIM images. Corrected NN distances (NN distances after subtracting the random object distribution) are displayed as mean per image. Data is shown as median with interquartile range from all images (N = 60) of 3 independent experiments with 2 technical duplicates ∗ = p < 0.05 (two-tailed Man–Whitney test).