Fig. 7.

Effects of calpain knockdown on cyclic stretch-induced p120 loss and gap formation. MLE-12 epithelial cells were transfected with scrambled and calpain-1 siRNAs. At 48 h posttransfection, cells were then exposed to cyclic stretch (20%) for 2 h. Calpain-1, calpain-2, and p120 protein expression and epithelial barrier function were determined by Western blot analysis (A) and immunofluorescent staining, respectively (B). A: effect of calpain-1 siRNA on calpain-1 protein expression. B: effects of calpain-1 knockdown on cyclic stretch-induced p120 protein expression. C: after fixation and permeabilization, cells were incubated with anti-p120-catenin primary antibody followed by Alexa-conjugated secondary antibody (green). The F-actin and nucleus were stained with Alexa 546 phalloidin (red) and DAPI (blue), respectively. Scale bars = 5 μm.