Mutations in PLS affect MDA-MB-231 directed cell migration. MDA-MB-231 cells were cotransfected with p190A- and EGFP-expressing constructs, spread on gelatin coating, and visualized by epifluorescence and contrast time-lapse microscopy for 16 h. Frames were collected every 10 min. (A) Representative tracings of paths traveled over 16 h by MDA-MB-231 cells transfected with p190A mutants. (B) Quantification of movement directionality represented as a ratio of the distance between the start and end point over the total path traveled. (C) Cell velocity is calculated by length of the path traveled divided by time. Values are expressed as the mean ± SEM (n = 20 cells per condition). Statistical significance was calculated relative to nontransfected (NT) condition. *, P < 0.05; **, P < 0.01; ***, P < 0.001; n.s, not significant.