Ensembles of bidirectional kinesin Cin8 produce additive forces in both directions of movement Journal Article

Author(s): Fallesen, Todd; Roostalu, Johanna; Duellberg, Cristian; Pruessner, Gunnar; Surrey, Thomas
Article Title: Ensembles of bidirectional kinesin Cin8 produce additive forces in both directions of movement
Abstract: Most kinesin motors move in only one direction along microtubules. Members of the kinesin-5 subfamily were initially described as unidirectional plus-end-directed motors and shown to produce piconewton forces. However, some fungal kinesin-5 motors are bidirectional. The force production of a bidirectional kinesin-5 has not yet been measured. Therefore, it remains unknown whether the mechanism of the unconventional minus-end-directed motility differs fundamentally from that of plus-end-directed stepping. Using force spectroscopy, we have measured here the forces that ensembles of purified budding yeast kinesin-5 Cin8 produce in microtubule gliding assays in both plus- and minus-end direction. Correlation analysis of pause forces demonstrated that individual Cin8 molecules produce additive forces in both directions of movement. In ensembles, Cin8 motors were able to produce single-motor forces up to a magnitude of ∼1.5 pN. Hence, these properties appear to be conserved within the kinesin-5 subfamily. Force production was largely independent of the directionality of movement, indicating similarities between the motility mechanisms for both directions. These results provide constraints for the development of models for the bidirectional motility mechanism of fission yeast kinesin-5 and provide insight into the function of this mitotic motor.
Journal Title: Biophysical Journal
Volume: 113
Issue 9
ISSN: 1542-0086
Publisher: Biophysical Society  
Date Published: 2017-11-07
Start Page: 2055
End Page: 2067
Copyright Statement: CC BY
DOI: 10.1016/j.bpj.2017.09.006
Notes: The plasmid for full-length kinesin-1 was a gift from G. Holzwarth and J. Macosko with permission from J. Howard. We thank I. Lueke and N. I. Cade for technical assistance. G.P. thanks the Francis Crick Institute, and in particular the Surrey and Salbreux groups, for their hospitality during his sabbatical stay, as well as Imperial College London for making it possible. This work was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK (FC001163), the United Kingdom Medical Research Council (FC001163), and the Wellcome Trust (FC001163), and by Imperial College London. J.R. was also supported by a Sir Henry Wellcome Postdoctoral Fellowship (100145/Z/12/Z) and T.S. by the European Research Council (Advanced Grant, project 323042).
Open access: yes (OA journal)