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Published on: August 27, 2013
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Activity pulses induce spontaneous flow reversals in viscoelastic environments
Emmanuel L C Vi M Plan1,2, Julia M Yeomans3, Amin Doostmohammadi4
1Institute of Theoretical and Applied Research, Duy Tan University, Ha Noi 100 000, Viet Nam.
Journal of the Royal Society, Interface
|April 14, 2021
Summary
Cellular activity pulses in viscoelastic environments can reverse their own flow direction. This study reveals how interactions between active gels and their surroundings control cell movement and function.
Area of Science:
- Biophysics
- Soft Matter Physics
- Cellular Mechanics
Background:
- Cellular functions like proliferation and motility are mechanically regulated by extracellular matrices.
- Actomyosin activity in cellular systems often exhibits pulsating behavior.
Purpose of the Study:
- To numerically explore spontaneous flow generation by activity pulses in a viscoelastic medium.
- To understand the mechanism of flow reversal due to active gel-environment interactions.
Main Methods:
- Utilizing an active gel model for numerical simulations.
- Analyzing the interplay between activity-induced deformations and the medium's time-dependent response.
Main Results:
- Demonstrated reversal of spontaneously generated active flows.
- Identified the crucial role of relaxation time scales of polymers and active particles.
- Provided a phase space for observing spontaneous flow reversals.
Conclusions:
- Cross-talk between active gels and viscoelastic environments can lead to flow reversal.
- Controlled activity pulses may regulate cell behavior in complex microenvironments.
- Suggests new experimental avenues for studying cellular mechanics.
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