Bidirectional organelle transport can occur in cell processes that contain single microtubules.
Intracellular organelle transport was studied in a new model system, the giant freshwater ameba Reticulomyxa. The ameba extends a large reticulate network of cytoplasmic strands in which various phase-dense organelles can be seen to move at a rate of up to 25 microns/s. This combined light and high voltage electron microscopic study shows that organelles move bidirectionally in even the finest network strands that contain only a single microtubule. In terms of microtubule-associated intracellular transport, this observation defines a minimum set of conditions necessary for such movement. The implications of this finding for possible models of force generation are discussed.
D000656:Amoeba / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure*; D000818:Animals; D008854:Microscopy, Electron; D008870:Microtubules / Q000502:physiology / Q000648:ultrastructure*; D009940:Organoids / Q000502:physiology / Q000648:ultrastructure*