Chronology of motor-mediated microtubule streaming
- Forschungszentrum Jülich, Germany
Abstract
We introduce a computer-based simulation model for coarse-grained, effective motor-mediated interaction between microtubule pairs to study the time-scales that compose cytoplasmic streaming. We characterise microtubule dynamics in two-dimensional systems by chronologically arranging five distinct processes of varying duration that make up streaming, from microtubule pairs to collective dynamics. The structures found were polarity sorted due to the propulsion of antialigned microtubules. This also gave rise to the formation of large polar-aligned domains, and streaming at the domain boundaries. Correlation functions, mean squared displacements, and velocity distributions reveal a cascade of processes ultimately leading to microtubule streaming and advection, spanning multiple microtubule lengths. The characteristic times for the processes span over three orders of magnitude from fast single-microtubule processes to slow collective processes. Our approach can be used to directly test the importance of molecular components, such as motors and crosslinking proteins between microtubules, on the collective dynamics at cellular scale.
Data availability
Source code and input files required to simulate microtubule-effective motor systems using the freely available, open-source Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) have been provided.
Article and author information
Author details
Funding
International Helmholtz Research School of Biophysics and Soft Matter (Graduate Student Fellowship)
- Özer Duman
- Guglielmo Saggiorato
The authors declare that there was no funding for this work.
Reviewing Editor
- Raymond E Goldstein, University of Cambridge, United Kingdom
Version history
- Received: June 29, 2018
- Accepted: December 28, 2018
- Accepted Manuscript published: January 2, 2019 (version 1)
- Version of Record published: January 18, 2019 (version 2)
Copyright
© 2019, Ravichandran 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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Chronology of motor-mediated microtubule streaming
eLife 8:e39694.
https://doi.org/10.7554/eLife.39694
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