Defective F-actin organization and β1 integrin activation in ADAP-deficient MKs upon spreading on Horm collagen. (A) Representative confocal images of cultured control and ADAP-deficient MKs 3 hours after spreading on Horm collagen, and stained for F-actin and active ITGB1 (β1 integrin). Scale bars represent 30 µm and 5 µm (inset). (B) Mean fluorescence intensity of F-actin (B) and active ITGB1 (F), and density of podosomes (C) in the lowest optical section of spread MKs. Area (D) and F-actin organization along collagen fibers (E) of spread MKs. (A-F) 100 MKs per genotype were analyzed. Box-and-whiskers plots display 5 and 95 percentiles. Data points below and above the whiskers are shown as individual points. The line in the middle of the box is plotted at the median (***P < .001). (G) Relative adhesive MKs in percent after 3 hours; representative graph from 2 independent experiments. Two biological replicates and 3 technical replicates were analyzed per experiments (*P < .05).