Fig. 1.

FBXW2 binds to β-catenin via its consensus degron motif. a Evolutionary conservation of FBXW2 degron motif on β-catenin. b, c FBXW2 binds to exogenously expressed (b) or endogenous β-catenin (c): HEK293 cells were transfected with indicated plasmids, followed by IP with anti-HA (b) or Flag Ab (c) and IB with indicated Abs. WCE: whole-cell extract. d FBXW2 binds to endogenous β-catenin: Cell lysates from H1299 cells were pulled down with anti-FBXW2 or anti-β-catenin Abs, followed by IB with indicated Abs. e The interaction between FBXW2 and β-catenin is dependent on the three S/T residues on the degron motif: β-catenin or its S→A or S→D mutants on FBXW2 degron motif was co-transfected with HA-FBXW2, followed by IP with HA Ab and IB with indicated Abs. f Endogenous FBXW2 binds to wild type β-catenin or its constitutively active mutants, but not its inactive mutants on the degron motif: H1299 cells were transfected with indicated plasmids, followed by IP with FBXW2 Ab and IB with indicated Abs. Unprocessed original scans of blots are shown in Supplementary Figure 9