title: Opposite-polarity motors activate one another to trigger cargo transport in live cells.
abstract: Intracellular transport is typically bidirectional, consisting of a series of back and forth movements. Kinesin-1 and cytoplasmic dynein require each other for bidirectional transport of intracellular cargo along microtubules; i.e., inhibition or depletion of kinesin-1 abolishes dynein-driven cargo transport and vice versa. Using Drosophila melanogaster S2 cells, we demonstrate that replacement of endogenous kinesin-1 or dynein with an unrelated, peroxisome-targeted motor of the same directionality activates peroxisome transport in the opposite direction. However, motility-deficient versions of motors, which retain the ability to bind microtubules and hydrolyze adenosine triphosphate, do not activate peroxisome motility. Thus, any pair of opposite-polarity motors, provided they move along microtubules, can activate one another. These results demonstrate that mechanical interactions between opposite-polarity motors are necessary and sufficient for bidirectional organelle transport in live cells.
authors.affiliation: Department of Cell and Molecular Biology, Northwestern University, Chicago, IL 60611, USA.
authors.forename: Shabeen
authors.initials: S
authors.lastname: Ally
authors.forename: Adam G
authors.initials: AG
authors.lastname: Larson
authors.forename: Kari
authors.initials: K
authors.lastname: Barlan
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Rice
authors.forename: Vladimir I
authors.initials: VI
authors.lastname: Gelfand
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002478:Cells, Cultured; D029721:Drosophila Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D004331:Drosophila melanogaster / Q000378:metabolism*; D004398:Dyneins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D016547:Kinesins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D008869:Microtubule-Associated Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D008870:Microtubules / Q000378:metabolism; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D020675:Peroxisomes / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D008869:Microtubule-Associated Proteins; D020409:Molecular Motor Proteins; C515209:Khc protein, Drosophila; D004398:Dyneins; D016547:Kinesins