Kinesin and dynein use distinct mechanisms to bypass obstacles
Abstract
Kinesin-1 and cytoplasmic dynein are microtubule (MT) motors that transport intracellular cargos. It remains unclear how these motors move along MTs densely coated with obstacles of various sizes in the cytoplasm. Here, we tested the ability of single and multiple motors to bypass synthetic obstacles on MTs in vitro. Contrary to previous reports, we found that mammalian dynein is highly capable of bypassing obstacles. Human kinesin-1 motors fail to avoid obstacles, consistent with their inability to take sideways steps on to neighboring MT protofilaments. Kinesins overcome this limitation when working in teams, bypassing obstacles as effectively as multiple dyneins. Cargos driven by multiple kinesin or dyneins are also capable of rotating around the MT to bypass large obstacles. These results suggest that multiplicity of motors is required not only for transporting cargos over long distances and generating higher forces, but also for maneuvering of the cargos on obstacle-coated MT surfaces.
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All data generated or analyzed during this study will be included in the manuscript and supporting files.
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Funding
National Institute of General Medical Sciences (GM094522)
- Ahmet Yildiz
National Science Foundation (MCB-1055017)
- Ahmet Yildiz
National Science Foundation (MCB-1617028)
- Ahmet Yildiz
National Institute of General Medical Sciences (GM123655-03)
- Luke S Ferro
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Ferro et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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