Relative GATA-1 occupancy at a subset of preCRMs. Using antibodies directed against the estrogen-receptor moiety of the GATA-1-ER fusion protein (E) and the N terminus of GATA-1 (G), chromatin fragments were immunoprecipitated from untreated G1E-ER4 cells (uninduced) and G1E-ER4 cells treated with estradiol for 24 h (induced). Normal mouse (m) and rat (r) IgG controls were performed in parallel. Real-time polymerase chain reactions of each amplicon were performed in duplicate and quantified using SYBR green dye. Signals were referenced to a dilution series of the relevant input sample. Amplicons from the β-major globin promoter (Hbb-b1 prom) and an upstream region of the Zfpm promoter (Zfpm1UP) are shown as positive and negative controls.
