Extra- and intracellular ECM-associated granules. (A) Granules in the extracellular space close to collagen fibers and amorphous matrix. (B) Granules in the intracellular space, in the main cell body as well as in a cellular protrusion. Granules are indicated by a light green arrowhead. (C) Intracellular granules close to the plasma membrane, next to actin filaments and with two microtubules interspersed. (D) A granule release site, where granules are in both the intra- and extracellular space. The plasma membrane is partially interrupted. The top panel shows a slice of a tomogram acquired at this site. This tomogram was segmented using deep-learning based software (Dragonfly) and visualized using ChimeraX. The middle panel shows an overlay of the segmentation and the tomogram panel shown above. The lower panel shows the segmentation at an oblique angle of 30° for better visibility of the ECM fibers. The color scheme for the different segmented cellular and ECM components is described in the figure. All slices (1.71 nm thickness) are from IsoNet-processed tomograms. Scale bar dimensions are 100 nm.