Polarity patterns of stress fibers

Abstract

Stress fibers are contractile actomyosin bundles commonly observed in the cytoskeleton of metazoan cells. The spatial profile of the polarity of actin filaments inside contractile actomyosin bundles is either monotonic (graded) or periodic (alternating). In the framework of linear irreversible thermodynamics, we write the constitutive equations for a polar, active, elastic one-dimensional medium. An analysis of the resulting equations for the dynamics of polarity shows that the transition from graded to alternating polarity patterns is a nonequilibrium Lifshitz point. Active contractility is a necessary condition for the emergence of sarcomeric, alternating polarity patterns.

5 pages, 3 figures

References in corpus (6)

• Generic theory of active polar gels: a paradigm for cytoskeletal dynamics
• Complex Spontaneous Flows and Concentration Banding in Active Polar Films
• Self-organization and Mechanical Properties of Active Filament Bundles
• Hydrodynamics of isotropic and liquid crystalline active polymer solutions
• Spontaneous waves in muscle fibres
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Cited by in corpus (8)

• Physics of adherent cells
• Contractile units in disordered actomyosin bundles arise from F-actin buckling
• Spontaneous contractility--mediated cortical flow generates cell migration in 3-dimensional environments
• Active nonreciprocal attraction between motile particles in an elastic medium
• Substrate rigidity deforms and polarizes active gels
• Spatio-temporal dynamics of an active, polar, viscoelastic ring
• Contraction of cross-linked actomyosin bundles
• Nonlinear dynamics and fluctuations in biological systems (Habilitation thesis)