A mechano-osmotic feedback couples cell volume to the rate of cell deformation
- Institut Curie, CNRS, UMR 144, France
- European Molecular Biology Laboratory, Germany
- Laboratoire Interdisciplinaire de Physique, France
- Sorbonne Université, INSERM, France
- Institut Curie, CNRS UMR168, France
Abstract
Mechanics has been a central focus of physical biology in the past decade. In comparison, how cells manage their size is less understood. Here we show that a parameter central to both the physics and the physiology of the cell, its volume, depends on a mechano-osmotic coupling. We found that cells change their volume depending on the rate at which they change shape, when they spontaneously spread are externally deformed. Cells undergo slow deformation at constant volume, while fast deformation leads to volume loss. We propose a mechano-sensitive pump and leak model to explain this phenomenon. Our model and experiments suggest that volume modulation depends on the state of the actin cortex and the coupling of ion fluxes to membrane tension. This mechano-osmotic coupling defines a membrane tension homeostasis module constantly at work in cells, causing volume fluctuations associated with fast cell shape changes, with potential consequences on cellular physiology.
Data availability
All data generated or analysed during this study are included in themanuscript and supporting file; all the raw analysed data shown in thefigure panels in the article are available in the accompanying SourceData files
Article and author information
Author details
Stéphane Vassilopoulos
Jean-François Joanny
Funding
Agence Nationale de la Recherche (ANR-19-CE13-0030)
- Matthieu Piel
Agence Nationale de la Recherche (ANR-10-EQPX-34)
- Matthieu Piel
Agence Nationale de la Recherche (ANR-10-IDEX-0001-02 PSL)
- Matthieu Piel
Agence Nationale de la Recherche (ANR-10-LABX-31)
- Matthieu Piel
Fondation pour la Recherche Médicale (FDT201805005592)
- Larisa Venkova
Human Frontier Science Program (LT000305/2018-L)
- Nishit Srivastava
Agence Nationale de la Recherche (ANR‐17‐CE13‐0020‐02)
- Amit Singh Vishen
European Union's Horizon 2020 research and innovation programme (Marie Sklodowska-Curie grant agreement no. 641639)
- Larisa Venkova
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Venkova 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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A mechano-osmotic feedback couples cell volume to the rate of cell deformation
eLife 11:e72381.
https://doi.org/10.7554/eLife.72381
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