Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2007 Feb 20;104(8):2703-8. Epub 2007 Feb 14.

Glucocorticoid-stimulated preadipocyte differentiation is mediated through acetylation of C/EBPbeta by GCN5.

Author information

1
Graduate Program in Biochemistry and Department of Biochemistry, University of Ottawa, Ottawa, ON, Canada K1N 6N5.

Abstract

Preadipocyte differentiation in culture is driven by an insulin and cAMP dependant transcriptional cascade which induces the bzip transcription factors C/EBPbeta and C/EBPdelta. We have previously shown that glucocorticoid treatment, which strongly potentiates this differentiation pathway, stimulates the titration of the corepressor histone deacetylase 1 (HDAC1) from C/EBPbeta. This results in a dramatic enhancement of C/EBPbeta-dependent transcription from the C/EBPalpha promoter, concomitant with potentiation of preadipocyte differentiation. Here, we show that C/EBPbeta is acetylated by GCN5 and PCAF within a cluster of lysine residues between amino acids 98-102 and that this acetylation is strongly induced by glucocorticoid treatment. Arginine substitution of the lysine residues within the acetylation motif of C/EBPbeta prevented acetylation and blocked the ability of glucocorticoids to enhance C/EBPbeta-directed transcription and to potentiate C/EBPbeta-dependent preadipocyte differentiation. Moreover, acetylation of C/EBPbeta appeared to directly interfere with the interaction of HDAC1 with C/EBPbeta, suggesting that PCAF/GCN5-dependent acetylation of C/EBPbeta serves as an important molecular switch in determining the transcriptional regulatory potential of this transcription factor.

PMID:
17301242
PMCID:
PMC1815245
DOI:
10.1073/pnas.0607378104
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center