Intracellular functions and motile properties of bi-directional kinesin-5 Cin8 are regulated by neck linker docking
Abstract
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.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. All Source data files have been provided.
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Author details
Funding
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.
Copyright
© 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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