Fig. 4. Endosome tubule formation is stimulated by CI-976. HeLa cells were incubated with Alexa568-Tf for 45 minutes to label endocytic compartments, CI-976 (25 µM) was added, and live cells were imaged immediately by spinning disk confocal microscopy. The time interval between each panel is 6.4 seconds. The arrows point to tubules that formed during the course of these observations. The micrographs are inverted images from the originals.