FIGURE 3.

PAI-1 KO β3-containing focal adhesions were enlarged and extended. WT and KO cells were immunostained for β3 (A and B). Insets, enlarged images of focal adhesions (arrows). Relative focal adhesion size between WT and KO cells was quantified using MetaMorph image analysis software (C). To demonstrate the co-localization of β3 and vinculin (a focal adhesion marker), WT and KO cells were co-immunostained for β3 and vinculin (A* and B**). To down-regulate PAI-1 in WT cells, WT cells were co-transfected with PAI-1 siRNA and GFP and then immunostained for vinculin (E). D, GFP alone. PAI-1 knockdown was confirmed using Real time PCR (F). PAI-1 knockdown led to a similar enlargement of focal adhesions compared with non-targeting siRNA controls (G). Bar, 20 μm. Approximately 300 focal adhesions were analyzed in each of three experiments.