Collective dynamics of actomyosin cortex endow cells with intrinsic mechanosensing properties

  title={Collective dynamics of actomyosin cortex endow cells with intrinsic mechanosensing properties},
  author={Jocelyn {\'E}tienne and Jonathan Fouchard and D{\'e}mosth{\`e}ne Mitrossilis and Nathalie Bufi and Pauline Durand-Smet and Atef Asnacios},
Living cells adapt and respond actively to the mechanical properties of their environment. In addition to biochemical mechanotransduction, evidence exists for a myosin-dependent, purely mechanical sensitivity to the stiffness of the surroundings at the scale of the whole cell. Using a minimal model of the dynamics of actomyosin cortex, we show that the interplay of myosin power strokes with the rapidly remodelling actin network results in a regulation of force and cell shape that adapts to the… 
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Viscoelasticity Acts as a Marker for Tumor Extracellular Matrix Characteristics
  • C. Mierke
  • Biology, Engineering
    Frontiers in Cell and Developmental Biology
  • 2021
This review article illustrates the importance of the tumor extracellular matrix mechano-phenotype, including the phenomenon viscoelasticity in identifying, characterizing, and treating specific cancer types.


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It is shown that large-scale mechanosensing leads to an adaptative response of cell migration to stiffness gradients, and not only that cells migrate preferentially toward stiffer substrates, but also that this response is optimal in a narrow range of rigidities.
Single-cell response to stiffness exhibits muscle-like behavior
An unexpected mechanism of rigidity sensing is revealed, whereby the contractile acto-myosin units themselves can act as sensors, and could thus coordinate local activity of adhesion complexes and guide cell migration along rigidity gradients.
Filamentous network mechanics and active contractility determine cell and tissue shape.
Computer simulations and theoretical modeling demonstrate that filamentous network mechanics and contractility give rise to a modified Laplace law that quantitatively explains the experimental findings on both cell and tissue scales.
Active multistage coarsening of actin networks driven by myosin motors
It is proposed that the physical origin of this multistage aggregation is the highly asymmetric load response of actin filaments: they can support large tensions but buckle easily under piconewton compressive loads.
Rigidity-driven growth and migration of epithelial cells on microstructured anisotropic substrates
The behavior of epithelial cells cultured on microfabricated substrates engineered to exhibit an anisotropic stiffness shows that the mechanical interactions of cells with their microenvironment can be tuned to engineer particular tissue properties.
Cytoskeletal coherence requires myosin-IIA contractility
It is suggested that NMIIA creates a coherent actin network through the formation of circumferential actin bundles that mechanically link elements of the peripheral actin cytoskeleton where much of the force is generated during spreading.
Real-time single-cell response to stiffness
A unique method is developed allowing us to tune, in real time, the effective stiffness experienced by a single living cell in a uniaxial traction geometry, and suggests that early cell response could be mechanical in nature.
Load-dependent mechanism of nonmuscle myosin 2
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