FIG. 8.

HDAC1 and mSin3A corepressors associate with the RTA promoter in BCBL1 cells. ChIP assays were carried out on nonreactivated versus reactivated BCBL1 cells using antibodies specific to endogenous HDAC1, mSin3A, and NCoR. Reactivated BCBL1 cells were treated with 20 ng/ml TPA and 3 mM NaB. PCR amplification was carried out on the immunoprecipitates using primers against the RTA promoter region to determine whether endogenous RTA promoter DNA was associated with the candidate repressors. Control PCR amplifications were carried out using GAPDH and ORF73 promoter-specific primers. RTA expression was detected following TPA/NaB reactivation by immunoblotting using RTA-specific IgG, and equal loading was shown using actin-specific IgG (lower panel). IP, immunoprecipitation.