Figure 7.

The disruption of Ecad cis-oligomerization impairs collective cell migration. Cells were phase-contrast imaged starting at the time the PDMS block was removed (t₀) and for 24 h. (A, left) Examples of the evolution of the migration front in function of time for wt Ecad and cis-Ecad expressing cells. Bar, 50 µm. Plots show the front migration displacement in function of time (middle) and the normalized front roughness in function of time (right). n = 12 and 17 for wt Ecad and cis-Ecad expressing cells, respectively. (B) Single cell tracking was performed over the first 8 h of the 24-h movies. Phase-contrast images of wt Ecad (left) and cis-Ecad (right) expressing monolayers taken at t₀ with superimposed 8-h trajectories of single cells at the front and rear (cells of the fifth row away from the edge). Bars, 50 µm. Plots of 8-h trajectories of front (blue curves) and rear (red curves) cells for wt Ecad and cis-Ecad expressing monolayers. Axes are scaled in micrometers; n = 48 and 36 trajectories for wt Ecad and cis-Ecad expressing cells, respectively. cis-Ecad cells migrate on significant larger distances than wt Ecad cells both at the front and rear. (C) MSD as a function of time for trajectories presented in B and fits by the equation (MSD = 4Dt² + v²t²). D: Histograms showing the D and v values (± SEM) extracted from the fits for wt Ecad and cis-Ecad front and rear cells.