Traction force dynamics in a dHL60 cell. (A) Kymograph of the instantaneous magnitude of the traction stresses (top), axial stresses (middle), and axial traction tension (bottom) shown every 6 s for a chemotaxing dHL60 cell. The black arrow indicates pseudopod protrusion, followed by front TA formation (green arrow). The red arrow shows the transition of the front TA to the back. The blue arrow points to the back TA loss. The inclined red and black lines indicate the instantaneous position of the front and back cell edges. (B) Average maps of the magnitude of total (left), axial (middle), and lateral (right) traction stresses in cell-based coordinates for the cell shown in A.