THE DIRECTION OF CYCLIC STRETCH-INDUCED CELL AND STRESS FIBER ALIGNMENT DEPENDS ON MATRIX RIGIDITY

摘要

Cell-matrix forces, and hence cell contractile forces, are attenuated on soft substrates. On a soft collagen gel, stretch promoted SF formation parallel to the direction of stretch in cells with attenuated contractility caused by adhesion on a soft matrix. These results confirm results from our previous studies showing that stretching promotes SF assembly when cell contractility is attenuated with pharmacological inhibitors. We submit that actomyosin sliding mediates the strong dependence on strain rate in cells on a collagen gel subjected to steady and cyclic stretch, consistent with the strain rate response we have observed in cells stretched on rigid elastomer. Together, these results suggest a role for myosin Ⅱ motors regulated by MLCK.