Migration, chemotaxis, and traction forces of cells with different expression patterns of NMIIA and NMIIB. (A) Speed of randomly migrating REF-52 and COS-7 cells in indicated conditions. Top and bottom of a box indicate 75th and 25th quartiles, respectively; whiskers encompass all data, the dot is the mean, and the middle line is the median. Asterisks indicate statistical significance (*, P < 0.05; **, P < 0.01; ***, P < 0.001, Dunn’s multiple comparisons test); N, number of cells. (B) Wind-rose histograms of PDGF chemotaxis of REF-52 and COS-7 cells expressing indicated constructs. The length of each leaflet corresponds to the percentage of cells migrating in the direction of leaflet. (C) Forward migration indices of REF-52 and COS-7 cells migrating toward the PDGF gradient (mean ± 95% confidence interval). Forward migration index reflects directionality; values >0.1 are considered directional. Asterisks indicate statistical significance (***, P < 0.001, Dunn’s multiple comparisons test); N, number of cells. (D) Examples of traction stress maps for REF-52 cells on ∼25-kPa polyacrylamide gels in indicated conditions. Bar, 20 µm; color bar units, pascals. (E) Plot with quantification of total force per cell (****, P < 0.0001, nonparametric ANOVA with Dunn’s multiple comparisons test).