Figure 6.

15d-PGJ₂ abrogates p300 recruitment to SBE. A) DNA affinity precipitation assays. Nuclear extracts from fibroblasts treated with TGF-β in the presence and absence of 15d-PGJ₂ were incubated with biotin-labeled oligonucleotide probes harboring consensus SBE sequences, and subjected to DNA affinity precipitation assay (DAPA), as described in Materials and Methods. Representative images are shown. B) ChIP assays. Formaldehyde cross-linked nuclear extracts were subjected to ChIP using indicated antibodies or IgG. Immunoprecipitated DNA was amplified using primers spanning for TGF-β response element of COL1A2 promoter. Representative images are shown. C) Immunoprecipitated DNA was subjected to real-time quantitative PCR using COL1A2 promoter-specific primers. Results are expressed as fold change in DNA precipitated by the indicated antibody from TGF-β-treated cultures (solid bars) compared to control cultures (open bars) in the presence and absence of 15d-PGJ₂ and represent means ± sd of triplicate determinations.