Fig. 5. De-repression of Hox genes in Suz12^-/- ES cells correlates with reduction of Rnf2 association to Hox genomic regions. (A) The association of Suz12, Eed, Rnf2 and H3-K27 trimethylation at the Hox promoter regions in the wild-type and suz12^-/- ES cells. Whole-cell lysates prepared from approximately the same number of wild type (+/+) and suz12^-/- (-/-) ES cells were subjected to ChIP analyses using anti-Suz12, -Eed, -trimethylated H3-K27 and -Rnf2 antibodies. For the `Input', genomic DNA extracted from the original whole cell lysate equivalent to the 1/40 volume of that used for the ChIP analysis was subjected to the PCR. Hprt was used as a control. (B) The expression of Hox cluster genes in the wild type (+/+) and suz12^-/- (-/-) ES cells was compared by RT-PCR.