Hysteresis in the cell response to time-dependent substrate stiffness.
Mechanical cues like the rigidity of the substrate are main determinants for the decision-making of adherent cells. Here we use a mechano-chemical model to predict the cellular response to varying substrate stiffnesses. The model equations combine the mechanics of contractile actin filament bundles with a model for the Rho-signaling pathway triggered by forces at cell-matrix contacts. A bifurcation analysis of cellular contractility as a function of substrate stiffness reveals a bistable response, thus defining a lower threshold of stiffness, below which cells are not able to build up contractile forces, and an upper threshold of stiffness, above which cells are always in a strongly contracted state. Using the full dynamical model, we predict that rate-dependent hysteresis will occur in the cellular traction forces when cells are exposed to substrates of time-dependent stiffness.
Besser
Achim
A
Bioquant, University of Heidelberg, Heidelberg, Germany.
Schwarz
Ulrich S
US
D001696:Biomechanical Phenomena; D002477:Cells / Q000166:cytology* / Q000378:metabolism; D007700:Kinetics; D008954:Models, Biological; D022502:Stress Fibers / Q000378:metabolism; D013997:Time Factors