Fig. 5: LUXendin651 and LUXendin645 allow nanoscopic detection of GLP1R.

a LUXendin645 allows super-resolution snapshots of MIN6 β-cells using widefield microscopy combined with super-resolution radial fluctuations (SRRF) (representative image from n = 8 images, three independent repeatss) (scale bar = 10 µm for full-field images, 2.5 µm for zoomed-in images). b–d Confocal and STED snapshots of endogenous GLP1R in LUXendin651-treated MIN6 cells at FWHM = 70 ± 10 nm (mean ± s.d.; n = 15 line profiles measured on the raw data, two independent repeats). Note the presence of punctate GLP1R expression as well as aggregation/clustering in cells imaged just away from b, close to c or next to d the coverslip using STED microscopy (representative image from n = 8 images, three independent repeats) (scale bar = 2 µm for full-field images, 1 µm for zoomed-in images). e, f Representative graph showing spatial analysis of GLP1R expression patterns using the F-function e and G-function f, which show distribution (red line) vs. a random model (black line; 95% confidence interval shown) (n = 6 from three independent repeats). g Approximately 1 in 4 MIN6 β-cells possess highly concentrated GLP1R clusters. h, i LUXendin651 allows GLP1R to be imaged in living MIN6 cells using SRRF h and STED i (representative image from n = 6 and 18 images, three independent repeats for SRRF and STED, respectively) (scale bar = 10 µm for full-field SRRF image, 2.5 µm for the zoomed-in image) (scale bar = 2 µm for STED images). White boxes show the ___location of zoom-ins. The following compound concentrations were used: 100 nM LUXendin645 (SRRF) and 100–400 nM LUXendin651 (STED). Mean ± s.e.m. are shown. Source data are provided as a Source Data file.