1.

TGF-β1 induces nuclear translocation of β-catenin without affecting the steady-state protein level of β-catenin and independent of canonical Wnt signaling pathway. (A) Cytosolic and nuclear fractions of protein lysates were isolated from human MSCs treated or untreated with TGF-β1 for 2 h or Wnt3A for 6 h. Western blot was probed with an anti-β-catenin monoclonal antibody. (B) β-catenin localization was detected by immunofluorescence with the anti-β-catenin antibody after cells were treated or untreated with TGF-β1 for 1 h. (C) Cytosolic and nuclear fraction of protein lysates were isolated from MDCK cells treated or untreated with TGF-β1 for 2 h. Western blots were probed with anti-β-catenin antibody. (D) Cytosolic and nuclear fraction of protein lysates were isolated from MDCK cells treated or untreated with Wnt3A. Western blots were probed with anti-β-catenin antibody. (E) Total cell lysates were prepared from MSCs after treatment with TGF-β1 or Wnt3A for 24 h. Western blots were probed with anti-β-catenin antibody. (F) MSCs were pretreated with protein translation inhibitor cyclohexmide for 1 h before TGF-β1 treatment for 2 h. Cytosolic and nuclear fractions of β-catenin were detected by anti-β-catenin antibody. (G) MSCs were pretreated with CHX for 1 h before TGF-β1 treatment for 6 h. Protein levels of β-catenin and PAI-1 in whole-cell lysates were determined by Western blot with anti-β-catenin and PAI-1 antibodies. (H) MSCs were pretreated with Fz8CRD containing conditioned medium for 6 h before TGF-β1 treatment for 2 h. Nuclear fractions of β-catenin were detected by anti-β-catenin antibody. (I) The levels of nuclear β-catenin in vector control and DVL-ΔPDZ adenovirus-infected MSCs treated with TGF-β1 for 2 h were determined by Western blot analysis.