Fig. 8. Schematic representation of the proposed mechanism of SMA-FP action and stress-fiber-formation. (a) -SMA incorporation in pre-existing cytoplasmic-actin-containing stress fibers represented as light red dashed lines. -SMA is first recruited in RLSs, a pre-requisite step before its incorporation in stress fibers (see arrows). (b) -SMA incorporation into stress fibers (dark red lines) confers higher cell-contractility (illustrated by the arrows on the top of the cell). When such contractile cells are treated with SMA-FP, -SMA incorporation in stress fibers is inhibited (see zoomed-in part of the cell c), resulting in -SMA accumulation in RLSs, its disappearance from stress fibers, and subsequently `relaxation' of the cell.