FIG. 4.

RIP140 is acetylated at lysine 446. (A) Eleven nanomoles of recombinant GST-RIP140 (1-495) wild type or K446Q mutant was incubated with full-length, baculovirus-purified p300 (1 pmol) in the presence of [³H]AcCoA. Reactions were analyzed by SDS-PAGE and visualized by fluorography. (B) Recombinant GST-RIP140 (1-495) (25 and 300 ng) was acetylated or mock acetylated with p300. Samples were electrophoresed on a 10% polyacrylamide gel and subjected to Western analysis using an antibody directed against acetylated (top) or unacetylated (bottom) RIP140. (C) In the top panels, endogenous RIP140 was immunoprecipitated from COS7 and HepG2 cells with a RIP140 antibody and subjected to Western analysis using the acetylated K446 RIP140 antibody. Middle panels show cells transfected with full-length CBP before immunoprecipitation. Total RIP140 proteins immunoprecipitated from these cells are shown in the bottom panels.