Figure 5. Kindlin-1 activates TGF-β/Smad3 signaling in CRC cells.

A. Kindlin-1 potentiates TGF-β1 activation on Smad3. Flag or Flag-Kindlin-1 expression vector was transfected into SW1116 cells for 36h followed by treatment of TGF-β1 (5ng/ml) for another 12h. Proteins were extracted for Western blot analysis using indicated antibodies. B. Kindlin-1 is required for TGF-β1 activation on Smad3. Control or Kindlin-1 siRNA was transfected into HCT116 cells for 36h followed by treatment of TGF-β1 (5ng/ml) for another 12h. Proteins were extracted for Western blot analysis using indicated antibodies. C. Kindlin-1 is required for translocation of phosphorylated Smad3 into the nucleus. Left panel: Flag or Flag-Kindlin-1 expression vector was transfected into SW1116 cells for 36h followed by treatment of TGF-β1 (5ng/ml) for another 12h. Right panel: Control or Kindlin-1 siRNA was transfected into HCT116 cells for 36h followed by treatment of TGF-β1 (5ng/ml) for another 12h. Nuclear proteins were extracted for Western blot analysis. The presence of YY1 indicates that the fraction was derived from the nuclei. D. Kindlin-1 is required for TGF-β1 target gene expression. Left panel: Flag or Flag-Kindlin-1 expression vector was transfected into SW1116 cells for 36h followed by treatment of TGF-β1 (5ng/ml) for another 12h. Western blot analysis was performed using indicated antibodies. Right panel: Control or Kindlin-1 siRNAs was transfected into HCT116 cells, followed by treatment of TGF-β1 (5ng/ml) for another 12h. Western blot analysis was performed using indicated antibodies.