Stiffness of actin networks cross-linked with filamin-A increases with increasing shear prestress. Measurements were carried out using a stress-controlled parallel plate rheometer in gels with different actin concentration (cA) and different molar ratios of filamin-A (R): cA = 36 μM, R = 1/100 (open squares); cA = 48 μM, R = 1/100 (solid squares); cA = 74 μM, R = 1/100 (diamonds); cA = 36 μM, R = 1/50 (left-pointing triangles); cA = 53 μM, R = 1/50 (upward-pointing triangles). For comparison, data from measurements in living airway smooth muscle cells (202) are included (solid circles near the top right corner). Modified from reference 66 with permission from Gardel et al.