α-Catenin plays a role in TGF-β-induced EMT. (A) Top: α-Catenin and β-catenin localize at the cell edge, but β-catenin is missing from the edge upon α-catenin KD. Middle: N-cadherin is localized in cell–cell junctions (right) but not at the cell edge (left) in WT MEFs. Bottom: Mature FAs (yellow arrow) form in extensions rich with α-catenin in cells that also form α-catenin–rich cell–cell contacts (white arrow). (B) Immunoblot for α-catenin showing KD in MDCK and NMuMG cells. (C) WT and α-catenin KD MDCK cells stained for E-cadherin and vimentin after 48 h on FN-coated glass without stimulation for EMT. (D) Quantifications of E-cadherin, vimentin, and α-SMA intensity in WT and KD cells untreated or after 72 h treatment with TGFβ. (E) WT and α-catenin KD MDCK cells stained for E-cadherin and vimentin after 72 h incubation with TGFβ (10 ng/ml) on FN-coated soft (0.2-kPa) and stiff (25-kPa) matrices. n > 22 cells in each case. (F) α-Catenin KD MEFs expressing WT GFP-α-catenin or GFP-α-catenin L344P, plated for 24 h on 0.2-kPa FN-coated matrices. The L344P mutant localizes to actin bundles in central regions of the cells (similar to Fig. 3, C and E). Statistical analysis comparing the relative intensities of the EMT markers was performed by ANOVA followed by Tukey’s post hoc test correction (**, P < 0.01; ***, P < 0.001; ****, P < 0.0001). Source data are available for this figure: SourceData FS5.