title: NuRD complex component Mi-2beta binds to and represses RORgamma-mediated transcriptional activation.
abstract: RORgamma is a nuclear receptor that binds to DNA motifs as a monomer to constitutively activate target genes. RORgamma plays an important role in thymocyte development and lymph node organogenesis, while the regulation of RORgamma-mediated transcriptional activation is currently unclear. The purpose of this study was to identify other nuclear proteins that interact with RORgamma. A yeast two-hybrid screen with Y190 yeast cells under stringent conditions resulted in the identification of CHD4, also known as Mi-2beta, as a RORgamma-interacting protein. This interaction was confirmed by GST pull-down assays. This interaction occurred within the middle regulatory region (amino acids 719-1164) of Mi-2beta. Transfection of Gal4-RORgamma into HeLa cells resulted in constitutive transactivation of the MH100-tk-luc reporter. The addition of Mi-2beta resulted in a dramatic 50% decrease in Gal4-RORgamma-mediated transactivation. These data demonstrate that RORgamma forms a protein-protein interaction with the regulatory region of Mi-2beta, resulting in inhibition of RORgamma transcriptional activity. These results may provide evidence as to how RORgamma-mediated transactivation is regulated by other nuclear proteins.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Johnson
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Lovett
authors.forename: Michael
authors.initials: M
authors.lastname: Hirsch
authors.forename: Fang
authors.initials: F
authors.lastname: Xia
authors.forename: J Don
authors.initials: JD
authors.lastname: Chen
mesh_terms: D000818:Animals; D018076:DNA, Complementary / Q000235:genetics; D015723:Gene Library; D017930:Genes, Reporter / Q000235:genetics; D006367:HeLa Cells; D006655:Histone Deacetylases / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex; D051379:Mice; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D011485:Protein Binding; D018168:Receptors, Retinoic Acid / Q000235:genetics / Q000378:metabolism*; D011988:Receptors, Thyroid Hormone / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D015533:Transcriptional Activation / Q000502:physiology*; D014162:Transfection; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D009687:Nuclear Proteins; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; C539900:RORC protein, human; D018168:Receptors, Retinoic Acid; D011988:Receptors, Thyroid Hormone; D012097:Repressor Proteins; C539901:Rorc protein, mouse; D006655:Histone Deacetylases; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex