Contractile network models for adherent cells

Abstract

Cells sense the geometry and stiffness of their adhesive environment by active contractility. For strong adhesion to flat substrates, two-dimensional contractile network models can be used to understand how force is distributed throughout the cell. Here we compare the shape and force distribution for different variants of such network models. In contrast to Hookean networks, cable networks reflect the asymmetric response of biopolymers to tension versus compression. For passive networks, contractility is modeled by a reduced resting length of the mechanical links. In actively contracting networks, a constant force couple is introduced into each link in order to model contraction by molecular motors. If combined with fixed adhesion sites, all network models lead to invaginated cell shapes, but only actively contracting cable networks lead to the circular arc morphology typical for strongly adhering cells. In this case, shape and force distribution are determined by local rather than global determinants and thus are suited to endow the cell with a robust sense of its environment. We also discuss non-linear and adaptive linker mechanics as well as the relation to tissue shape.

35 pages, 14 postscript figures, to appear in Physical Review E

References in corpus (2)

• Effect of adhesion geometry and rigidity on cellular force distributions
• Stiff Polymers, Foams and Fiber Networks

Cited by in corpus (8)

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• Polymorphism and bistability in adherent cells
• Contour models of cellular adhesion
• A stochastic modeling framework for single cell migration: coupling contractility and focal adhesions
• Microscopic biophysical model of self-organization in tissue due to feedback between cell- and macroscopic-scale forces