Figure 7.

Acetylation of TAF9 results in the disassembly of the TFIID complex. A) GST, GST-TAF9, or GST-TAF9 K5Q protein was immobilized on glutathione agarose beads and incubated with 3134 cell extracts. The associated protein was subjected to SDS-PAGE and was Western blotted with indicated Abs. B) Cell extracts from wild-type (WT) and TAF9-knockdown (KD) 3134 cells were immunoprecipitated (IP) with TBP Ab. The resulting immunoprecipitates were subjected to Western blot with indicated Abs. C) Model for HDAC1-dependent gene activation and acetylated HDAC1 mediated gene repression. TAF9 is deacetylated in the presence of HDAC1, and the TFIID complex is recruited to PU.1 promoter, which results in gene activation (left). HDAC1 is acetylated or inactivated by HDACi, which causes an inability to deacetylate TAF9 (right). Acetylated TAF9 is displaced from DNA. Acetylated TAF9 also causes the disassembly of the TFIID complex from the promoter, which results in gene repression. Inr, initiator. Asterisk indicates GST proteins.