(A) (Top) Membrane marker Skylan-NS-TOM20 showing mitochondria in a COS-7 cell at 23°C, color-coded for distance from the substrate. (Bottom) Evolution of individual mitochondria, showing fission and fusion events, the former preceded by mitochondrial constriction (Movie 10 and fig. S44). (B) Time-lapse distribution of Golgi-resident enzyme Skylan-NS-Mann II in a U2OS cell at 23°C, showing centralized cisternae surrounded by vesicles. White arrowheads indicate a docking vesicle, and red arrowheads highlight rapid export of a long tubular vesicle (movies S17 and S18). Scale bars, 5 μm (A), top; 1 μm (A), bottom; and 3 μm (B).