Cellular adhesiveness, contractility, and traction: Stick, grip, and slip control

Translocation of cells over solid substrata depends on generation of motive force, in crawling tissue cells, brought about by regulated contractility of intracellular actomyosin. Intracellular contractile machinery has a direct, structural connection to the cell surface. Hence, regulated adhesiveness of the cell surface provides a mechanism whereby a cell can fine tune the extent of tractional forces that are necessary for effective translocation. Cells are able to control adhesiveness of surfaces (stick), contractility (grip), and the extent of traction exerted on the substratum (slip). Here, I discuss several aspects of local (subcellular) regulation of adhesiveness and contractility and speculate on how cells, given a choice of the substratum, decide on how and where to apply traction.