Tug-of-war as a cooperative mechanism for bidirectional cargo transport by molecular motors.
Intracellular transport is based on molecular motors that pull cargos along cytoskeletal filaments. One motor species always moves in one direction, e.g., conventional kinesin moves to the microtubule plus end, whereas cytoplasmic dynein moves to the microtubule minus end. However, many cellular cargoes are observed to move bidirectionally, involving both plus- and minus-end-directed motors. The presumably simplest mechanism for such bidirectional transport is provided by a tug-of-war between the two motor species. This mechanism is studied theoretically using the load-dependent transport properties of individual motors as measured in single-molecule experiments. In contrast to previous expectations, such a tug-of-war is found to be highly cooperative and to exhibit seven different motility regimes depending on the precise values of the single motor parameters. The sensitivity of the transport process to small parameter changes can be used by the cell to regulate its cargo traffic.
Müller
Melanie J I
MJ
Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany.
Klumpp
Stefan
S
Lipowsky
Reinhard
R
D000818:Animals; D001692:Biological Transport; D002465:Cell Movement; D016764:Cell Polarity; D004330:Drosophila / Q000166:cytology; D004398:Dyneins / Q000378:metabolism; D016547:Kinesins / Q000378:metabolism; D050356:Lipid Metabolism; D008870:Microtubules / Q000378:metabolism; D008954:Models, Biological; D020409:Molecular Motor Proteins / Q000378:metabolism*; D009154:Mutation / Q000235:genetics
D020409:Molecular Motor Proteins; D004398:Dyneins; D016547:Kinesins