FIGURE 6.

Zyxin-mediated cell motility is integrin α5β1-dependent. A, a scratch wound assay was carried out in confluent cultures of zyxin siRNA-transfected A549 cells. An isotype control anti-IgG or anti-integrin α5 antibody (1:100) was added to the culture medium, and wound closure was measured in the presence and absence of TGF-β1. The percentage of wound closure was determined 24 h after injury. Representative phase contrast images of wounded areas are shown. Data are mean ± S.D. from three independent experiments; ***, p < 0.001. B, A549 cells transfected with either control siRNA (ctr siRNA) or zyxin siRNA (zyx siRNA) were grown for 24 h in TGF-β1-containing medium in the presence or absence of anti-integrin α5 inhibitory antibody. Anti-IgG was used as an isotype control. Cells were lysed, and Western blotting was performed with whole cell lysates by using anti-integrin α5, anti-phospho-Src (Tyr416) (pSrc (Tyr416)), or anti-Src antibody. Equal protein loading was confirmed by reprobing the stripped blots with an anti-β-actin antibody. Representative blots are shown. Densitometric analysis was used to determine the phospho-Src/Src ratio (ImageJ software). Data are shown as mean ± S.E.; **, p < 0.01.