TGF-β1 induces EMT in renal tubular epithelial cells. (A) Phase contrast (left) and Phalloidin staining (right) of mTEC-KO cells incubated for 72 hours as indicated without TGF-β1, with 100 pM TGF-β1, or with TGF-β1 and 10 μM SB431542. Cell morphology was observed by bright field phase microscopy at 100× magnification. Phalloidin was used to detect F-actin at 400× magnification, while DAPI was used to detect nuclei. White arrows point to stress fibers. (B) Immunoblot showing protein expression of E-cadherin, α-SMA, and β-tubulin following incubation of mTEC-KO cells with 100 pM TGF-β1 for the indicated times. A dash indicates non-detectable levels of protein, while a plus sign indicates detectable protein levels over background. (C-E) show quantitative RT-PCR analysis of (C) Ksp-cadherin, (D) MMP-9, and (E) SM22 RNA levels in mTEC-KO cells incubated with TGF-β1 for the indicated times. Asterisks (*) indicate significant differences (P < 0.05, n = 9).