Figure 5.

Durotaxis as a Result of Integrin Catch-Bond Dynamics

(A) Ten trajectories of durotacting cells on a matrix with slope 20 kPa/μm.

(B) X-coordinate of the cell as a function of time, on a matrix with slope 20 kPa/μm.

(C) X-coordinate of the cell as a function of time, on a matrix with slope 80 kPa/μm.

(D) Cell speed as a function of the slope of the stiffness gradient.

(E) Durotaxis speed in μm/h as a function of cell stiffness λ and cellular temperature T. Values: mean $\pm$ standard deviation over 25 simulations. Comparisons indicated by asterisks (∗∗∗p$<$0.001, ∗∗p$<$0.01, ∗p$<$0.05, ns: nonsignificant, i.e., p$>$0.05) based on ANOVA followed by Student's t test.

(F) A cartoon to schematically explain durotaxis based on our model. The cell forms protrusions (cyan) that either successfully get stuck to the ECM or are retracted. The cell experiences a stiffer substrate on the right, so forces develop much faster on the right, allowing FAs to stabilize there. At the left, FAs fail to stabilize, allowing the cell to retract in order to propel itself forward and generate new FAs at the front. This continues and the cell moves to the right.

See also Video S4, Figure S4C.