Chromatin immunoprecipitation of the Mcm4 promoter region. Chromatin fragments prepared from BM2 cells were subjected to immunoprecipitation using two different Myb-specific rabbit antisera raised against the DNA-binding domain of v-Myb (anti Myb a and b). Control immunoprecipitations were performed with two different batches of normal rabbit serum (NRS a and b) or anti-Flag antibodies (anti Flag). DNA isolated from the immunoprecipitates was analyzed by quantitative real-time PCR using primers specific for the Mcm4 promoter region (-0.55 kb, left panel) or for a region approximately 13 kb upstream of the Mcm4 gene (-13 kb, right panel). The columns indicate the amount of PCR product obtained relative to the anti-Flag control reaction.