Figure 7: Numerical simulation of the gap closure.
From: Mechanics of epithelial closure over non-adherent environments
(a) Schematic of the model showing a balance between the tension in the actin cable (green) T and the frictional force fy arising from tissue adhesion to substrate on the fibronectin (red) and the tissue itself represented as a viscoelastic material. (b) Average radial stress at the edge of the gap predicted by the model with (κ2 model) or without (κ model) reinforcement of tension in the actin purse-string. Change in the perimeter of the gap over time predicted by the tension reinforcement model for (c) 100 μm and (d) 200 μm diameter gaps. Simulation values have been scaled to fit the experimental data. (e) Kymograph of actin intensity from the centre of the gap. Black line is a guide to show an ~12 μm wide strip along the edge of the cell front. (f) Change in average intensity of actin with time in the strip of interest bounded by the black line in e. (g) Actin network visualized using GFP-lifeact-expressing HaCaT cells and (h) basal confocal section of cells fixed and stained for actin showing strong re-organization within cells localized to the edge of the gap (insets). Scale bars 20 μm.
