The histone acetylase PCAF is a nuclear receptor coactivator

Abstract

Whereas the histone acetylase PCAF has been suggested to be part of a coactivator complex mediating transcriptional activation by the nuclear hormone receptors, the physical and functional interactions between nuclear receptors and PCAF have remained unclear. Our efforts to clarify these relationships have revealed two novel properties of nuclear receptors. First, we demonstrate that the RXR/RAR heterodimer directly recruits PCAF from mammalian cell extracts in a ligand-dependent manner and that increased expression of PCAF leads to enhanced retinoid-responsive transcription. Second, we demonstrate that, in vitro, PCAF directly associates with the DNA-binding domain of nuclear receptors, independently of p300/CBP binding, therefore defining a novel cofactor interaction surface. Furthermore, our results show that dissociation of corepressors enables ligand-dependent PCAF binding to the receptors. This observation illuminates how a ligand-dependent receptor function can be propagated to regions outside the ligand-binding domain itself. On the basis of these observations, we suggest that PCAF may play a more central role in nuclear receptor function than previously anticipated.

Acetyltransferases (HATs) as Targets for Neurological Therapeutics

“…Auto-acetylated PCAF localizes to the nucleus and activates gene transcription. Deacetylated PCAF is located primarily in the cytoplasm of apoptotic cells, suggesting a role for PCAF auto-acetylation in the regulation of cellular processes [35]. Similarly, p300 and CBP activity is also regulated through auto-acetylation [36].…”

Adenoviruses with Tcf binding sites in multiple early promoters show enhanced selectivity for tumour cells with constitutive activation of the wnt signalling pathway

“…The ⌬N-␤-catenin plasmid was described by van de Wetering et al 41 The p300 vector contains HAtagged p300 expressed from the CMV promoter. The P/CAF expression vector was described by Blanco et al 42 The Tip49 and Tip49DN vectors were described by Wood et al 43 Cell lines ISREC-01, 44 SW480 (ATCC CCL-228) and Co115 23 were supplied by Dr B Sordat (ISREC). HCT116 (CCL-247), HT29 (HTB-38), 293T were supplied by ATCC.…”

An IFN-γ-Inducible Transcription Factor, IFN Consensus Sequence Binding Protein (ICSBP), Stimulates IL-12 p40 Expression in Macrophages

“…Because the Ets element is shown to bind a multiprotein complex (17), which is difficult to detect by standard EMSA, we employed an alternative, DNA affinity binding assay. Previously, we have successfully used this assay and described recruitment of multiple factors to specific regulatory elements, which was otherwise not detectable by EMSA (33,34). As schematically presented in Fig.…”

“…4A) by PCR using a biotinylated primer as detailed in (33). PCR products were purified by the Qiaquick Kit (Qiagen, Chatsworth, CA).…”