Chromatin was prepared from Hela cells according to the Abcam X-ChIP protocol. Cells were fixed with formaldehyde for 10mins. The  ChIP was performed with 25µg of chromatin, 8µg of  ab28180 (blue), and 20µl of Protein A/G sepharose beads. No antibody was added to the beads control (yellow). The immunoprecipitated DNA was quantified by real time PCR (Taqman and sybr green approach). Primers and probes for the actively transcribed genes GAPDH and ACT1 are located in the core promoter.