Targeting of SWI/SNF chromatin remodelling complexes to estrogen-responsive genes.
SWI/SNF complexes are ATP-dependent chromatin remodelling enzymes that have been implicated in the regulation of gene expression in yeast and higher eukaryotes. BRG1, a catalytic subunit in the mammalian SWI/SNF complex, is required for transcriptional activation by the estrogen receptor, but the mechanisms by which the complex is recruited to estrogen target genes are unknown. Here, we have identified an interaction between the estrogen receptor and BAF57, a subunit present only in mammalian SWI/SNF complexes, which is stimulated by estrogen and requires both a functional hormone-binding domain and the DNA-binding region of the receptor. We also found an additional interaction between the p160 family of coactivators and BAF57 and demonstrate that the ability of p160 coactivators to potentiate transcription by the estrogen receptor is dependent on BAF57 in transfected cells. Moreover, chromatin immunoprecipitation assays demonstrated that BAF57 is recruited to the estrogen-responsive promoter, pS2, in a ligand-dependent manner. These results suggest that one of the mechanisms for recruiting SWI/SNF complexes to estrogen target genes is by means of BAF57.
Pubmed ID: 12145209 RIS Download
Amino Acid Substitution | Animals | Binding Sites | COS Cells | Carcinoma | Cercopithecus aethiops | Chromosomal Proteins, Non-Histone | DNA Helicases | Estradiol | Estrogen Antagonists | Estrogen Receptor alpha | Gene Expression Regulation | HeLa Cells | Histone Acetyltransferases | Humans | Macromolecular Substances | Mice | Nuclear Proteins | Nuclear Receptor Coactivator 1 | Nuclear Receptor Coactivator 2 | Nuclear Receptor Coactivator 3 | Promoter Regions, Genetic | Protein Binding | Protein Interaction Mapping | Protein Structure, Tertiary | Receptors, Estrogen | Recombinant Fusion Proteins | Saccharomyces cerevisiae | Transcription Factors | Transcription, Genetic | Transfection | Tumor Cells, Cultured | Two-Hybrid System Techniques