Figure 1.

Scheme of the experimental approach of pulling membrane nanotubes and example line scans acquired with confocal and STED microscopy. (a) Schematic of the experiment. (b) Membrane nanotube extrusion as seen in confocal fluorescence imaging. (c) Confocal and (d) 3D STED image of a small portion of the extruded nanotube (scale bars correspond to 500 nm). (e, g) Schematic illustration and (f, h) experimentally acquired data from line scans (gray bands in panels e and g) across a membrane nanotube (red cylinder) when using confocal (e, f) and 3D STED (g, h) imaging; for lucidity, the rough dimensions of the scanning voxels are illustrated as gray ellipsoids in (e, g).