Fig. 4. Oct3/4 is required to engage PRC1 and PRC2 at target gene promoters. (A) Changes in expression levels for the selected Ring1B target genes after tetracycline treatment of ZHBTc4 ES cells were determined as described in Fig. 1E. (B) ChIP analysis showing binding of Ring1B and Eed and levels of H3K4me3 at the promoter regions of the selected target genes after tetracycline treatment of ZHBTc4 ES cells. The relative amount of immunoprecipitated DNA is depicted as a percentage of input. Error bars represent s.d. determined from at least three independent experiments. (C) ChIP-on-chip analysis showing the average Ring1B binding to the promoter regions (from -8 kb to +2 kb relative to the transcription start sites) of the target genes before and after conditional deletion of Oct3/4. (D) ChIP analysis showing binding of Oct3/4 at the promoter regions of the selected target genes after OHT treatment of Ring1A^-/-;Ring1B^fl/fl;Rosa26::CreERT2 ES cells. The relative amount of immunoprecipitated DNA is depicted as a percentage of input. Error bars represent s.d. determined from at least three independent experiments.