Figure 3.

Force mappings during directional cell migration without guiding pattern. (a) Cell started migration in contracted shape. (b), (c) Cell elongated along migration direction and exerted increasing traction force in both leading and trailing regions. (d) Trailing adhesive sites released and cell shape became contracted, which started second migration cycle. Contour of cell is indicated by yellow dashed line. Starting and ending positions are indicated by asterisk and dot in micrographs, respectively. Traction force is indicated by white arrow. Cell migration direction is described as shift of centroid of cell from beginning to end during single migration cycle, which is labelled using blue arrow.