Motor processivity and speed determine structure and dynamics of microtubule-motor assemblies
- California Institute of Technology, United States
- Stanford University, United States
Abstract
Active matter systems can generate highly ordered structures, avoiding equilibrium through the consumption of energy by individual constituents. How the microscopic parameters that characterize the active agents are translated to the observed mesoscopic properties of the assembly has remained an open question. These active systems are prevalent in living matter; for example, in cells, the cytoskeleton is organized into structures such as the mitotic spindle through the coordinated activity of many motor proteins walking along microtubules. Here, we investigate how the microscopic motor-microtubule interactions affect the coherent structures formed in a reconstituted motor-microtubule system. This question is of deeper evolutionary significance as we suspect motor and microtubule type contribute to the shape and size of resulting structures. We explore key parameters experimentally and theoretically, using a variety of motors with different speeds, processivities, and directionalities. We demonstrate that aster size depends on the motor used to create the aster, and develop a model for the distribution of motors and microtubules in steady-state asters that depends on parameters related to motor speed and processivity. Further, we show that network contraction rates scale linearly with the single-motor speed in quasi one-dimensional contraction experiments. In all, this theoretical and experimental work helps elucidate how microscopic motor properties are translated to the much larger scale of collective motor-microtubule assemblies.
Data availability
All data associated with this study are stored on the CaltechData archive at DOI 10.22002/D1.2152.
Article and author information
Author details
Funding
Foundational Questions Institute (FQXi 1816)
- Rachel A Banks
- Vahe Galstyan
- Heun Jin Lee
- Soichi Hirokawa
- Matthew Thomson
- Rob Phillips
John Templeton Foundation (51250)
- Rachel A Banks
- Vahe Galstyan
- Heun Jin Lee
- Soichi Hirokawa
- Matthew Thomson
- Rob Phillips
National Institutes of Health (1R35 GM118043-01)
- Rachel A Banks
- Vahe Galstyan
- Heun Jin Lee
- Soichi Hirokawa
- Rob Phillips
John Templeton Foundation (60973)
- Rachel A Banks
- Vahe Galstyan
- Heun Jin Lee
- Soichi Hirokawa
- Matthew Thomson
- Rob Phillips
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Banks 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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Motor processivity and speed determine structure and dynamics of microtubule-motor assemblies
eLife 12:e79402.
https://doi.org/10.7554/eLife.79402
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