N-terminal β-strand of single-headed kinesin-1 can modulate the off-axis force-generation and resultant rotation pitch.

Autor: Yamagishi M; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.; Komaba Institute for Science, The University of Tokyo, Tokyo, Japan., Fujimura S; Department of Physics, Gakushuin University, Tokyo, Japan., Sugawa M; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.; Komaba Institute for Science, The University of Tokyo, Tokyo, Japan., Nishizaka T; Department of Physics, Gakushuin University, Tokyo, Japan., Yajima J; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.; Komaba Institute for Science, The University of Tokyo, Tokyo, Japan.; Research Center for Complex Systems Biology, The University of Tokyo, Tokyo, Japan.
Jazyk: angličtina
Zdroj: Cytoskeleton (Hoboken, N.J.) [Cytoskeleton (Hoboken)] 2020 Sep; Vol. 77 (9), pp. 351-361. Date of Electronic Publication: 2020 Sep 09.
DOI: 10.1002/cm.21630
Abstrakt: In in vitro microtubule gliding assays, most kinesins drive the rotation of gliding microtubules around their longitudinal axes in a corkscrew motion. The corkscrewing pitch is smaller than the supertwisted protofilament pitch of microtubules, indicating that the corkscrewing pitch is an inherent property of kinesins. To elucidate the molecular mechanisms through which kinesins corkscrew the microtubule, we performed three-dimensional tracking of a quantum dot bound to a microtubule translocating over a surface coated with single-headed kinesin-1 s under various assay conditions to alter the interactions between the kinesin and microtubule. Although alternations in kinesin concentration, ionic strength, and ATP concentration changed both gliding and rotational velocities, the corkscrewing pitch remained left-handed and constant at ~0.3 μm under all tested conditions apart from a slight increase in pitch at a low ATP concentration. We then used our system to analyze the effect of point mutations in the N-terminal β-strand protruding from the kinesin motor core and found mutations that decreased the corkscrewing pitch. Our findings confirmed that the corkscrewing motion of microtubules is caused by the intrinsic properties of the kinesin and demonstrates that changes in the active or retarding force originating from the N-terminal β-strand in the head modulate the pitch.
(© 2020 Wiley Periodicals LLC.)
Databáze: MEDLINE
Externí odkaz: