Figure 2.

Cells contract and retract asymmetrically when constrained by extracellular matrix patterns with underlying stiffness gradients. a) Cells patterned to X shapes with corners constrained by either stiff (dark rectangles) or soft regions contract to unique shapes depending on the stiffness boundary conditions. b) Magnitude of contraction for adhesions above soft regions for X-patterned cells. Contraction magnitude is similar across shapes, except for the asymmetric single stiff adhesion condition. Distal adhesions contract slightly higher in comparison to proximal adhesions, significance determined by student’s t-test, p < .031. Contraction of 6.5 μm corresponds to approximately 254 nN of force on soft regions. c) Relaxation of fibronectin patterns upon treatment with 25 μM of blebbistatin was observed by live-cell microscopy.