Intracellular functions and motile properties of bi-directional kinesin-5 Cin8 are regulated by neck linker docking
In this study, we analyzed intracellular functions and motile properties of neck-linker (NL) variants of the bi-directional S. cerevisiae kinesin-5 motor, Cin8. We also examined – by modeling – the configuration of H-bonds during NL docking. Decreasing the number of stabilizing H-bonds resulted in partially functional variants, as long as a conserved backbone H-bond at the N-latch position (proposed to stabilize the docked conformation of the NL) remained intact. Elimination of this conserved H-bond resulted in production of a non-functional Cin8 variant. Surprisingly, additional H-bond stabilization of the N-latch position, generated by replacement of the NL of Cin8 by sequences of the plus-end directed kinesin-5 Eg5, also produced a nonfunctional variant. In that variant, a single replacement of N-latch asparagine with glycine, as present in Cin8, eliminated the additional H-bond stabilization and rescued the functional defects. We conclude that exact N-latch stabilization during NL docking is critical for the function of bi-directional kinesin-5 Cin8.
All data generated or analysed during this study are included in the manuscript and supporting files. All Source data files have been provided.
Article and author information
Israel Science Foundation (ISF-386/18)
- Larisa Gheber
Isreal Binational Science Foundation (BSF-2015851)
- Larisa Gheber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Kristen J Verhey, University of Michigan, United States
- Preprint posted: May 29, 2020 (view preprint)
- Received: June 6, 2021
- Accepted: July 13, 2021
- Accepted Manuscript published: August 13, 2021 (version 1)
- Version of Record published: August 31, 2021 (version 2)
© 2021, Goldstein-Levitin 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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