N93K–myosin IIA or overexpressed α-actinin restores adhesion maturation in myosin IIA-deficient cells. (a–e) Time-lapse TIRF images of MIIA-depleted CHO.K1 cells expressing GFP–actin (control, a), GFP–MIIA (rescue, b), GFP–MIIA–N93K (c), GFP–MIIA–N93K with blebbistatin (20 μM, d), and α-actinin–GFP (e). Black and white panels show adhesions as revealed by co-expression of paxillin–mOrange in each case. Colour inserts are magnifications of the indicated regions in the black and white panels. Paxillin–mOrange is depicted in magenta in all cases and green represents GFP–actin (a), GFP–MIIA (b), GFP–MIIA-N93K (c, d) or α-actinin–GFP (e). Arrowheads indicate representative maturing adhesions. Panels a–c correspond to Supplementary Information, Movie 9 and panels d to Supplementary Information, Movie 10. (f) Quantification of the elongation index of maturing adhesions under the different conditions. Data are mean ± s.e.m., measured from more than 25 adhesions from 5–6 cells per condition (n = 30 for each condition). N/A, not applicable (MIIA-deficient cells contain no elongating adhesions). Scale bars are 5 μm.