Fig. 1.

E-cadherin localizes in nano-scale clusters. (A) Ecad-GFP localization appears continuous in the junctions of pancreatic cancer cells when imaged using confocal microscopy. Bar: 10 µm. (B) Fixed cells were imaged by serial confocal sectioning before and after ROI photobleaching (top and bottom panels respectively, arrow in bottom panel highlights region of photobleaching). 3D data sets were reconstructed as projections to visualize the cell junction along the z, y, and x-axes. The x-axis projection was cropped to the photobleached region, and shows that junctions were vertical and did not undercut adjacent cells. Bar: 2 µm. (C) At higher resolution it was apparent that E-cadherin was localized in clusters. (D) Examination of cells expressing lower levels of Ecad-GFP revealed that E-cadherin clusters maintained the same average size and number of monomers per cluster, but that the spacing between clusters increased. In 3D-STORM images the z-position of each molecule is color-coded and its intensity indicates positional accuracy according to the look-up table in each panel. Color bar in lower left of panels indicates the z-position range from −375 to +375 nm (left to right) and probability per nm² from 1.2×10⁻² to 1.4×10⁻⁵ (top to bottom). Bar in C,D: 200 nm.