Publications de Alexander Verkhovskiy

Traction Forces Control Cell-Edge Dynamics and Mediate Distance Sensitivity during Cell Polarization

Alexander Verkhovskiy, Zeno Messi, Franck Claude Raynaud, Alicia Carine Bornert

Traction forces are generated by cellular actin-myosin system and transmitted to the environment through adhesions. They are believed to drive cell motion, shape changes, and extracellular matrix remodeling [1 -3] . However, most of the traction force anal ...

2020

Traction forces mediate distance-sensitivity to control cell-edge activity during cell polarization

Alexander Verkhovskiy, Zeno Messi, Franck Claude Raynaud, Alicia Carine Bornert

AMER SOC CELL BIOLOGY2018

Minimal model for spontaneous cell polarization and edge activity in oscillating, rotating and migrating cells

Jean-Jacques Meister, Alexander Verkhovskiy, Mark Etienne Ambühl, Chiara Gabella, Franck Claude Raynaud, Alicia Carine Bornert

How cells break symmetry and organize activity at their edges to move directionally is a fundamental question in cell biology. Physical models of cell motility commonly incorporate gradients of regulatory proteins and/or feedback from the motion itself to ...

Nature Publishing Group2016

Microsurgery-aided in-situ force probing reveals extensibility and viscoelastic properties of individual stress fibers

Jean-Jacques Meister, Alexander Verkhovskiy, Chiara Gabella, Benoît Vianay, Céline Jeanne Labouesse

Actin-myosin filament bundles (stress fibers) are critical for tension generation and cell shape, but their mechanical properties are difficult to access. Here we propose a novel approach to probe individual peripheral stress fibers in living cells through ...

Nature Research2016

Cell Shape Dynamics Reveal Balance of Elasticity and Contractility in Peripheral Arcs

Jean-Jacques Meister, Alexander Verkhovskiy, Chiara Gabella, Benoît Vianay, Céline Jeanne Labouesse

The mechanical interaction between adherent cells and their substrate relies on the formation of adhesion sites and on the stabilization of contractile acto-myosin bundles, or stress fibers. The shape of the cell and the orientation of these fibers can be ...

Cell Press2015

Three-Dimensional Forces for Two-Dimensional Motion

Alexander Verkhovskiy

Elsevier2015

The mechanisms of spatial and temporal patterning of cell-edge dynamics

Alexander Verkhovskiy

Adherent cells migrate and change their shape by means of protrusion and retraction at their edges. When and where these activities occur defines the shape of the cell and the way it moves. Despite a great deal of knowledge about the structural organizatio ...

Elsevier2015

Ultra-soft cantilevers and 3-D micro-patterned substrates for contractile bundle tension measurement in living cells

Jean-Jacques Meister, Alexander Verkhovskiy, Chiara Gabella, Niccolo Piacentini, Benoît Vianay

Actin-myosin microfilament bundles or stress-fibers are the principal tension-generating structures in the cell. Their mechanical properties are critical for cell shape, motion, and interaction with other cells and extracellular matrix, but were so far dif ...

Royal Society of Chemistry2014

Contact Angle at the Leading Edge Controls Cell Protrusion Rate

László Forró, Jean-Jacques Meister, Alexander Verkhovskiy, Sylvia Jeney, Chiara Gabella, Elena Bertseva, Niccolo Piacentini, Alicia Carine Bornert

Plasma membrane tension and the pressure generated by actin polymerization are two antagonistic forces believed to define the protrusion rate at the leading edge of migrating cells [1-5]. Quantitatively, resistance to actin protrusion is a product of membr ...

Elsevier2014

Cell Polarization: Mechanical Switch for a Chemical Reaction

Alexander Verkhovskiy

Anterior-posterior polarity in the Caenorhabditis elegans zygote depends on two groups of PAR proteins, as well as on cortical flow. Recent work now demonstrates that this polarization results from a transition in a bistable reaction-diffusion system of PA ...

Elsevier2012

High-resolution cell outline segmentation and tracking from phase-contrast microscopy images

Jean-Jacques Meister, Alexander Verkhovskiy, Mark Etienne Ambühl, Charles Brepsant

Accurate extraction of cell outlines from microscopy images is essential for analysing the dynamics of migrating cells. Phase-contrast microscopy is one of the most common and convenient imaging modalities for observing cell motility because it does not re ...

2012

Dynamic measurement of the height and volume of migrating cells by a novel fluorescence microscopy technique

Jean-Jacques Meister, Alexander Verkhovskiy, Chiara Gabella, Lara Buscemi Estefanell, Benoît Vianay

We propose a new technique to measure the volume of adherent migrating cells. The method is based on a negative staining where a fluorescent, non-cell-permeant dye is added to the extracellular medium. The specimen is observed with a conventional fluoresce ...

2011

Interplay between cytoskeletal forces, membrane tension, and hydrostatic pressure in rapidly migrating cells

Jean-Jacques Meister, Alexander Verkhovskiy, Chiara Gabella, Elena Bertseva

Amer Soc Cell Biology2011

Force transmission in migrating cells

Jean-Jacques Meister, Alexander Verkhovskiy, Roger Sauser, Maxime Fred Maurice Fournier

During cell migration, forces generated by the actin cytoskeleton are transmitted through adhesion complexes to the substrate. To investigate the mechanism of force generation and transmission, we analyzed the relationship between actin network velocity an ...

Rockefeller University Press2010

Cell-Matrix Adhesion: Slip and Immobilization under Force

Alexander Verkhovskiy

When force is applied to cell-matrix adhesion complexes, they respond by growing larger and stronger. It emerges that strengthening involves transient motion of the transmembrane integrin receptors and their eventual immobilization to the extracellular mat ...

Elsevier2010

Role of focal adhesions and mechanical stresses in the formation and progression of the lamellum interface

Alexander Verkhovskiy

Actin network in the front part of a moving cell is organized into a lamellipodium and a lamellum. A distinct lamellipodium-lamellum interface is associated with focal adhesions and consists of a series of arclike segments linking neighboring focal adhesio ...

2009

Comparative dynamics of retrograde actin flow and focal adhesions: formation of nascent adhesions triggers transition from fast to slow flow

Jean-Jacques Meister, Alexander Verkhovskiy, Sébastien Schaub

Dynamic actin network at the leading edge of the cell is linked to the extracellular matrix through focal adhesions (FAs), and at the same time it undergoes retrograde flow with different dynamics in two distinct zones: the lamellipodium (peripheral zone o ...

Public Library of Science2008

Comparative maps of motion and assembly of filamentous actin and myosin II in migrating cells

Jean-Jacques Meister, Sophie Bohnet, Alexander Verkhovskiy, Sébastien Schaub

To understand the mechanism of cell migration, one needs to know how the parts of the motile machinery of the cell are assembled and how they move with respect to each other. Actin and myosin II are thought to be the major structural and force-generating c ...

American Society for Cell Biology2007

Analysis of actin filament network organization in lamellipodia by comparing experimental and simulated images

Jean-Jacques Meister, Alexander Verkhovskiy, Sébastien Schaub

Protrusion of lamellipodia during cell migration depends on the assembly of actin network. The assembly mechanism, based on dendritic filament branching, has been investigated in reconstituted in vitro systems, but little is known about the dynamical and s ...

Company of Biologists2007

Gradient of Rigidity in the Lamellipodia of Migrating Cells Revealed by Atomic Force Microscopy

Jean-Jacques Meister, Giovanni Dietler, Alexander Verkhovskiy, Sandor Kasas, Alexandre Yersin

Changes in mechanical properties of the cytoplasm have been implicated in cell motility, but there is little information about these properties in specific regions of the cell at specific stages of the cell migration process. Fish epidermal keratocytes wit ...

2005