Structural basis of cooperativity in kinesin revealed by 3D reconstruction of a two-head-bound state on microtubules
Abstract
The detailed basis of walking by dimeric molecules of kinesin along microtubules has remained unclear, partly because available structural methods have been unable to capture microtubule-bound intermediates of this process. Utilizing novel electron cryomicroscopy methods, we solved structures of microtubule-attached, dimeric kinesin bound to an ATP analog. We find that under these conditions, the kinesin dimer can attach to the microtubule with either one or two motor domains, and we present sub-nanometer resolution reconstructions of both states. The former structure reveals a novel kinesin conformation that revises the current understanding of how ATP binding is coupled to forward stepping of the motor. The latter structure indicates how tension between the two motor domains keeps their cycles out of phase in order to stimulate directional motility. The methods presented here pave the way for future structural studies of a variety of challenging macromolecules that bind to microtubules and other filaments.
Data availability
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Dimeric Kinesin-1 on Microtubules with ADP-AlFxPublicly available at the Electron Microscopy Data Bank (accession no. EMD-8546).
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Kinesin-1 Binding Microtubules with ADP-AlFx in a One-head-bound State (low-pass filtered to 8.5 angstrom)Publicly available at the Electron Microscopy Data Bank (accession no. EMD-8547).
Article and author information
Author details
Funding
American Cancer Society (ACS-IRG-58-012-55)
- Charles Vaughn Sindelar
National Institutes of Health (R01 GM 110530-01)
- Charles Vaughn Sindelar
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany
Version history
- Received: December 21, 2016
- Accepted: May 9, 2017
- Accepted Manuscript published: May 15, 2017 (version 1)
- Version of Record published: June 5, 2017 (version 2)
Copyright
© 2017, Liu 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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