FIG. 1.

β-Catenin is acetylated in vivo. (A) 293 cells were transfected with T41A-β-catenin (5 μg) either alone or together with 5 μg of p300 or the empty vector. After metabolic labeling with ³H-labeled sodium acetate, proteins were immunoprecipitated (IP) with β-catenin antibodies and resolved on SDS-PAGE. The gel was then exposed to X-ray film (top panel). Immunoprecipitated proteins were analyzed by Western blotting (WB) with anti-β-catenin antibodies (bottom panel). (B) Endogenous β-catenin was immunoprecipitated from 293 or SW480 cells with anti-β-catenin antibodies. Control immunoprecipitation was performed with an anti-Flag antibody. The samples were resolved by SDS-PAGE, and acetylation was assessed with anti-acetyl-lysine antibodies (upper panel). The amount of β-catenin in the immunoprecipitates was determined with anti-β-catenin antibodies (bottom panel).