Figure 3

p300 regulates acetylation and the protein level of ERα. (a) HeLa cells were transiently transfected with 2 μg Myc-ERα with or without 2 μg Myc-p300. Then 500 μg whole-cell lysate was immunoprecipitated (IP) using anti-acetylated-lysine (Ac-Lys) or normal IgG antibodies, and probed by anti-ERα antibody. The expression of proteins was analyzed by western blot (WB) using anti-Myc or anti-ERα antibody as input. (b) HeLa cells were transiently transfected with 2 μg Myc-ERα or the indicated amounts of Myc-p300 or empty vector. The expression of proteins was analyzed by WB using anti-ERα, anti-Myc or anti-p300 antibodies. (c) HeLa cells were transiently transfected with 4 μg Myc-ERα and treated with or without 1 μM trichostatin A (TSA) for 3 hours. Then 500 μg whole-cell lysate was immunoprecipitated using anti-p300 or normal IgG antibodies, and probed by anti-Myc antibody.