title: Estradiol repression of tumor necrosis factor-alpha transcription requires estrogen receptor activation function-2 and is enhanced by coactivators.
abstract: The tumor necrosis factor-alpha (TNF-alpha) promoter was used to explore the molecular mechanisms of estradiol (E(2))-dependent repression of gene transcription. E(2) inhibited basal activity and abolished TNF-alpha activation of the TNF-alpha promoter. The E(2)-inhibitory element was mapped to the -125 to -82 region of the TNF-alpha promoter, known as the TNF-responsive element (TNF-RE). An AP-1-like site in the TNF-RE is essential for repression activity. Estrogen receptor (ER) beta is more potent than ERalpha at repressing the -1044 TNF-alpha promoter and the TNF-RE upstream of the herpes simplex virus thymidine kinase promoter, but weaker at activating transcription through an estrogen response element. The activation function-2 (AF-2) surface in the ligand-binding domain is required for repression, because anti-estrogens and AF-2 mutations impair repression. The requirement of the AF-2 surface for repression is probably due to its capacity to recruit p160 coactivators or related coregulators, because overexpressing the coactivator glucocorticoid receptor interacting protein-1 enhances repression, whereas a glucocorticoid receptor interacting protein-1 mutant unable to interact with the AF-2 surface is ineffective. Furthermore, receptor interacting protein 140 prevents repression by ERbeta, probably by interacting with the AF-2 surface and blocking the binding of endogenous coactivators. These studies demonstrate that E(2)-mediated repression requires the AF-2 surface and the participation of coactivators or other coregulatory proteins.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
authors.forename: J
authors.initials: J
authors.lastname: An
authors.forename: R C
authors.initials: RC
authors.lastname: Ribeiro
authors.forename: P
authors.initials: P
authors.lastname: Webb
authors.forename: J A
authors.initials: JA
authors.lastname: Gustafsson
authors.forename: P J
authors.initials: PJ
authors.lastname: Kushner
authors.forename: J D
authors.initials: JD
authors.lastname: Baxter
authors.forename: D C
authors.initials: DC
authors.lastname: Leitman
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D001665:Binding Sites; D004958:Estradiol / Q000494:pharmacology*; D020847:Estrogen Receptor Modulators / Q000494:pharmacology; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D005786:Gene Expression Regulation; D008024:Ligands; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism; D051958:Nuclear Receptor Coactivator 2; D000078723:Nuclear Receptor Interacting Protein 1; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D020218:Response Elements; D020845:Selective Estrogen Receptor Modulators / Q000378:metabolism; D018139:Simplexvirus / Q000201:enzymology / Q000235:genetics; D013937:Thymidine Kinase / Q000235:genetics; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D020847:Estrogen Receptor Modulators; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D008024:Ligands; D009687:Nuclear Proteins; D051958:Nuclear Receptor Coactivator 2; D000078723:Nuclear Receptor Interacting Protein 1; D011960:Receptors, Estrogen; D020845:Selective Estrogen Receptor Modulators; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D004958:Estradiol; D013937:Thymidine Kinase