During cell movement, adhesions form at the cell's leading edge and cell detachment occurs at the rear. On , Andrew Doyle and Juliet Lee examine how these processes are coordinated in fast-moving fish keratinocytes. In these cells, calcium transients triggered by activation of stretch-activated calcium channels (SACs) induce spatially coordinated increases in traction stress that promote protrusion at the cell front and induce retraction at the rear. The authors use traction and imaging assays to show that cyclic changes in traction stress, cell shape and cell speed are associated with SAC-induced calcium transients. Inhibition of calcium transients increases adhesiveness at the rear of the cell, thus preventing retraction and slowly increasing traction stress. By contrast, induction of a calcium transient increases traction stress and adhesion disassembly at the rear of the cells, resulting in rapid retraction and reduction of cytoskeletal stress. The authors conclude that calcium transients coordinate changes in cellular adhesiveness with SAC-mediated cycles of mechanochemical feedback and thus allow fish keratinocytes to move quickly and efficiently.
