The kinesin-5 tail domain directly modulates the mechanochemical cycle of the motor domain for anti-parallel microtubule sliding
- University of California, Davis, United States
- The Scripps Research Institute, United States
- University of Vermont, United States
- Rensselaer Polytechnic Institute, United States
- Lerner Research Institute, Cleveland Clinic, United States
- Yale University, United States
- Mayo Clinic, United States
- Ben Gurion University of the Negev, Israel
Abstract
Kinesin-5 motors organize mitotic spindles by sliding apart microtubules. They are homotetramers with dimeric motor and tail domains at both ends of a bipolar minifilament. Here, we describe a regulatory mechanism involving direct binding between tail and motor domains and its fundamental role in microtubule sliding. Kinesin-5 tails decrease microtubule-stimulated ATP-hydrolysis by specifically engaging motor domains in the nucleotide-free or ADP states. Cryo-EM reveals that tail binding stabilizes an open motor domain ATP-active site. Full-length motors undergo slow motility and cluster together along microtubules, while tail-deleted motors exhibit rapid motility without clustering. The tail is critical for motors to zipper together two microtubules by generating substantial sliding forces. The tail is essential for mitotic spindle localization, which becomes severely reduced in tail-deleted motors. Our studies suggest a revised microtubule-sliding model, in which kinesin-5 tails stabilize motor domains microtubule-bound states by slowing ATP-binding resulting in high-force production at both homotetramer ends.
Data availability
Two atomic coordinate files for Dm-KLP61F motor ATP-like MT(alpha-beta-tubulin) model is available at Protein Data Bank (PDB-ID: #XXXX. The Dm-KLP61F motor nucleotide-free MT(alpha-beta-tubulin) asymmetric unit Protein Data BankPDB-ID: #XXXXThe refined Dm-KLP61F motor AMPPNP MT cryo-EM map is available at the Electron microscopy Data bank (EMBD) EMDB ID:#XXXXand the Dm-KLP61F motor-tail nucleotide free MT cryo-EM map is available at Electron microscopy Data bank (EMBD) EMDB-iD:#XXXXDm-KLP61F motor-tail nucleotide free MT cryo-EM map (focused 3D-classification map) is available at the Electron microscopy Data bank (EMBD)EMDB-ID:#XXXX
Article and author information
Author details
Stanley Nithianantham
Charles Vaughn Sindelar
Funding
National Science Foundation (1615991)
- Jawdat Al-Bassam
National Institutes of Health (GM110283)
- Jawdat Al-Bassam
National Institutes of Health (GM121491)
- Jason Stumpff
National Institutes of Health (GM130556)
- Jason Stumpff
Israel Science Foundation (ISF 386/18)
- Larisa Gheber
United States-Israel Binational Science Foundation (BSF-2015851)
- Larisa Gheber
National Institutes of Health (GM130556)
- Richard J McKenney
National Institutes of Health (GM052468)
- Ron Milligan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Bodrug 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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The kinesin-5 tail domain directly modulates the mechanochemical cycle of the motor domain for anti-parallel microtubule sliding
eLife 9:e51131.
https://doi.org/10.7554/eLife.51131
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