ChIP analysis of sheared chromatin from 10? HeLa cells using GTX60824 Histone H3K9me3 (Tri-methyl Lys9) antibody - ChIP grade. A titration consisting of 1, 2, 5 and 10 microg of antibody per ChIP experiment was analyzed. IgG (2 microg/IP) was used as a negative IP control. Quantitative PCR was performed with primers specific for the promoter of the active genes GAPDH and EIF4A2, used as negative controls, and for ZNF510 and the Sat2 satellite repeat, used as positive controls. The figure shows the recovery, expressed as a % of input (the relative amount of immunoprecipitated DNA compared to input DNA after qPCR analysis).