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arXiv · 1404.3478

Environmental control of microtubule-based bidirectional cargo-transport

Sarah Klein·Cécile Appert-Rolland·Ludger Santen
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Abstract

Inside cells, various cargos are transported by teams of molecular motors. Intriguingly, the motors involved generally have opposite pulling directions, and the resulting cargo dynamics is a biased stochastic motion. It is an open question how the cell can control this bias. Here we develop a model which takes explicitly into account the elastic coupling of the cargo with each motor. We show that bias can be simply controlled or even reversed in a counterintuitive manner via a change in the external force exerted on the cargo or a variation of the ATP binding rate to motors. Furthermore, the superdiffusive behavior found at short time scales indicates the emergence of motor cooperation induced by cargo-mediated coupling.

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Sarah Klein, Cécile Appert-Rolland, Ludger Santen. 2014-04-14. Environmental control of microtubule-based bidirectional cargo-transport. https://doi.org/10.1209/0295-5075%2F107%2F18004

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