Fig. 1. Near-confluent cells were de-roofed by a sonication procedure (D-F) or left untreated (A-C), fixed and stained for F-actin using TRITC-phalloidin (A,D). Untreated cells showed an abundance of stress fibers (A) terminating in paxillin-containing plaques (B). The size and shape of paxillin-containing patches was unchanged after the de-roofing step (E), indicating the preservation of FA complexes. FAs also stained positive for F-actin although the link between FAs and stress fibers was generally broken during de-roofing (D). Bar, 10 µm.