Coupling traction force patterns and actomyosin wave dynamics reveals mechanics of cell motion

The famous scallop theorem proposed by Purcell in 1977 states that self-propelled objects swimming at low Reynolds number must follow a cycle of shape changes that breaks temporal symmetry. This should hold true for crawling cells as well. However a clear mechanism for this symmetry breaking is still elusive. Here we show that cells embedded in 3D matrix form at both sides of the nucleus force dipoles driven by myosin that locally and periodically pinch the matrix. Using a combination of 3D live cell imaging, traction force microscopy and a minimal model with multipolar expansion, we show that the existence of a phase shift between the two dipoles involves mainly the microtubular network and is required for directed cell motion. We confirm this mechanism by triggering local dipolar contractions with a laser, which leads to directed motion. Our study reveals that the cell controls its motility by synchronising dipolar forces distributed at front and back. This result opens new strategies to externally control cell motion.

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Application of Digital Volume Correlation Algorithm to Cell Mechanics

Volume 11: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2009-13253 ◽

2009 ◽

Author(s):

Hyock J. Kwon ◽

Boxin Zhao ◽

Praveen N. P. Rao

Keyword(s):

Cell Mechanics ◽

Cross Correlation ◽

Speckle Pattern ◽

Traction Force ◽

Force Sensor ◽

Digital Volume Correlation ◽

Linear Elasticity Theory ◽

3 Dimensional ◽

Soft Gels ◽

Cell Motion

This study developed a digital volume correlation (DVC) algorithm based on fast normalized cross-correlation to measure the 3-dimensional deformation of soft gels, which was further utilized as a force sensor for cell mechanics studies. The developed algorithm was applied to the 3-D volume images of a gel acquired by confocal microscope to measure the deformation of the gel. The gel contained uniformly-dispersed florescence-labeled microbeads so as to generate a necessary speckle pattern for cross-correlation. The developed algorithm has been validated both analytically and experimentally, and applied to investigate cell mechanics by measuring the displacement field induced by the cell motion. Then, surface traction force generated by cells can be quantified through the conventional linear elasticity theory without any further assumption.

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Wave Analysis of the Charge Density Wave Dynamics in the Molecular Conductor (Perylene)2Pt(mnt)2 (mnt=maleonitriledithiolate)

Journal de Physique I ◽

10.1051/jp1:1995149 ◽

1995 ◽

Vol 5 (5) ◽

pp. 539-545 ◽

Cited By ~ 8

Author(s):

J. Dumas ◽

N. Thirion ◽

M. Almeida ◽

E. B. Lopes ◽

M. J. Matos ◽

...

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Wave Analysis ◽

Wave Dynamics ◽

Molecular Conductor

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CHARGE DENSITY WAVE DYNAMICS IN THE INCOMMENSURATE AND COMMENSURATE TaS3

Le Journal de Physique Colloques ◽

10.1051/jphyscol/1983079 ◽

1983 ◽

Vol 44 (C3) ◽

pp. C3-1639-C3-1645 ◽

Cited By ~ 8

Author(s):

P. Monceau ◽

H. Salva ◽

Z. Z. Wang

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Wave Dynamics

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Nonlinear Wave Dynamics in the Surf Zone

Coastal Engineering 1996 ◽

10.1061/9780784402429.092 ◽

1997 ◽

Author(s):

O. R. Sørensen ◽

P. A. Madsen ◽

H. A. Schäffer

Keyword(s):

Nonlinear Wave ◽

Surf Zone ◽

Wave Dynamics

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Bitter Taste Receptor Agonist (Quinine) Induces Traction Force Reduction and Calcium Flux Increase in Airway Smooth Muscle Cells from Ovalbumin-Sensitized and Challenged Rats

Journal of Advances in Biomedical Engineering and Technology ◽

10.15379/2409-3394.2015.02.01.3 ◽

2015 ◽

Vol 2 (1) ◽

pp. 20-27 ◽

Cited By ~ 4

Author(s):

Linhong Deng ◽

◽

Huilong Zeng ◽

Yue Wang ◽

Mingzhi Luo ◽

...

Keyword(s):

Smooth Muscle ◽

Receptor Agonist ◽

Bitter Taste ◽

Taste Receptor ◽

Traction Force ◽

Calcium Flux ◽

Airway Smooth Muscle Cells ◽

Bitter Taste Receptor ◽

Force Reduction ◽

Flux Increase

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Soil/Tire Interaction Analysis Using FEM and FVM

Tire Science and Technology ◽

10.2346/1.2186786 ◽

2005 ◽

Vol 33 (1) ◽

pp. 38-62 ◽

Cited By ~ 17

Author(s):

S. Oida ◽

E. Seta ◽

H. Heguri ◽

K. Kato

Keyword(s):

Large Scale ◽

Interaction Analysis ◽

Yield Criterion ◽

Surrounding Medium ◽

Flow Analysis ◽

Measurement Data ◽

Traction Force ◽

Elastoplastic Material ◽

The Road ◽

Soil Flow

Abstract Vehicles, such as an agricultural tractor, construction vehicle, mobile machinery, and 4-wheel drive vehicle, are often operated on unpaved ground. In many cases, the ground is deformable; therefore, the deformation should be taken into consideration in order to assess the off-the-road performance of a tire. Recent progress in computational mechanics enabled us to simulate the large scale coupling problem, in which the deformation of tire structure and of surrounding medium can be interactively considered. Using this technology, hydroplaning phenomena and tire traction on snow have been predicted. In this paper, the simulation methodology of tire/soil coupling problems is developed for pneumatic tires of arbitrary tread patterns. The Finite Element Method (FEM) and the Finite Volume Method (FVM) are used for structural and for soil-flow analysis, respectively. The soil is modeled as an elastoplastic material with a specified yield criterion and a nonlinear elasticity. The material constants are referred to measurement data, so that the cone penetration resistance and the shear resistance are represented. Finally, the traction force of the tire in a cultivated field is predicted, and a good correlation with experiments is obtained.

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