Wild type + 2 µm Bro1 tomogram. This video shows a cluster of three endosomes from cells overexpressing full-length Bro1. Two of the endosomes are spherical, whereas one is tubular. The internal vesicles shown within the endosomes are in red, and the limiting endosomal membrane is yellow. You can see two vesicle budding profiles within the tubular endosome: one is smaller and spherical, the other is longer and tubular. One of the spherical MVBs has a dimple in the surface that was not counted as a budding profile, but we speculate that it may be the precursor to an internal vesicle structure.
