EZH2-mediated trimethylation of β-catenin induces β-catenin to interact with TCF1 and RNAPII
(A) Western blots of TCF1 immunoprecipitation (IP) performed using nuclear lysates prepared from PTEN knockdown (KD) and empty vector (EV) SW480 cells treated with 1 μM EZH2 inhibitor (EZH2i, GSK-503) or DMSO for 72 h. IgG IP serves as a negative control. Input is nuclear lysates used for IP.
(B) β-catenin IP performed using nuclear lysate prepared from PTEN KD and EV SW480 cells.
(C) Flag IP performed using nuclear lysates prepared from Flag-tagged β-catenin WT expressing SW480 cells treated with 1 μM EZH2 inhibitor (EZH2i, GSK-503) or DMSO for 72 h with or without co-treatment with 250 μM H2O2 for 30 min. Cells not expressing Flag plasmid were used as a negative control for the IP.
(D) Flag IPs were performed using nuclear lysate prepared from FLAG-β-catenin WT and FLAG-β-catenin K49R expressing SW480 cells. IP with beads only serves as a negative control.
(E) Flag IP performed using nuclear lysates prepared from FLAG-β-catenin WT and FLAG-β-catenin K49R expressing PTEN KD or EV SW480 cells. See also Figure S5.