Figure 4. The BAF complex binds preferentially to histone H3K14ac and promotes H2A displacement.

(A) Nuclear extracts derived from T47D-MTVL cells were used for pulldown experiments with the indicated H3 and H4 tail peptides coupled to beads. Immunoblotting was performed for the presence of components of the BAF and PBAF complex, histone H1 and PR. (B) Cells were untreated (0) or treated for 5 and 30 min with 10 nM R-5020 and subjected to ChIP assays with α-H4K8ac and α-H3K9ac specific antibodies. The precipitated DNA fragments were subjected to PCR analysis to test for the presence of sequences corresponding to the MMTV nucleosome B. Input material (1%) is shown for comparison. A representative of three independent experiments is shown. (C) Quantification of the interaction of selected human SWI/SNF subunits with the indicated H3 tail acetylated peptides. SILAC ratios represent the relative abundance of the ‘heavy’ (modified) to the ‘light’ (unmodified) peptide. The variation (in %) and the number of quantified peptides are indicated. (D) Left: T47D-MTVL cells were transfected with siRNAs and treated with hormone as indicated, subjected to ChIP assays using α-NF1, α-PR and α-H2A and primers for MMTV nucleosome B. Right: quantification of the results by real time PCR. A representative of three independent experiments is shown.