title: A novel SP1/SP3 dependent intronic enhancer governing transcription of the UCP3 gene in brown adipocytes.
abstract: Uncoupling protein (UCP) 3 is a mitochondrial inner membrane protein implicated in lipid handling and metabolism of reactive oxygen species. Its transcription is mainly regulated by peroxisome proliferator-activated receptors (PPAR), a family of nuclear hormone receptors. Employing bandshift assays, RNA interference and reporter gene assays we examine an intronic region in the UCP3 gene harboring a cis-element essential for expression in brown adipocytes. We demonstrate binding of SP1 and SP3 to this element which is adjacent to a direct repeat 1 element mediating activation of UCP3 expression by PPARγ agonists. Transactivation mediated by these elements is interdependent and indispensable for UCP3 expression. Systematic deletion uncovered a third binding element, a putative NF1 site, in close proximity to the SP1/3 and PPARγ binding elements. Data mining demonstrated binding of MyoD and Myogenin to this third element in C2C12 cells, and, furthermore, revealed recruitment of p300. Taken together, this intronic region is the main enhancer driving UCP3 expression with SP1/3 and PPARγ as the core factors required for expression.
authors.affiliation: Molecular Nutritional Medicine, Else Kröner-Fresenius Center & Research Center for Nutrition and Food Sciences, Technische Universität München, Freising-Weihenstephan, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Hoffmann
authors.affiliation: Molecular Nutritional Medicine, Else Kröner-Fresenius Center & Research Center for Nutrition and Food Sciences, Technische Universität München, Freising-Weihenstephan, Germany.
authors.forename: Anika
authors.initials: A
authors.lastname: Zimmermann
authors.affiliation: Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Universitätsklinikum Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Hinney
authors.affiliation: Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Universitätsklinikum Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Anna-Lena
authors.initials: AL
authors.lastname: Volckmar
authors.affiliation: Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas, United States of America.
authors.forename: Harry W
authors.initials: HW
authors.lastname: Jarrett
authors.affiliation: Molecular Nutritional Medicine, Else Kröner-Fresenius Center & Research Center for Nutrition and Food Sciences, Technische Universität München, Freising-Weihenstephan, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Fromme
authors.affiliation: Molecular Nutritional Medicine, Else Kröner-Fresenius Center & Research Center for Nutrition and Food Sciences, Technische Universität München, Freising-Weihenstephan, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Klingenspor
mesh_terms: D052437:Adipocytes, Brown / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D006224:Cricetinae; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D007438:Introns; D007473:Ion Channels / Q000235:genetics*; D051379:Mice; D024101:Mitochondrial Proteins / Q000235:genetics*; D008954:Models, Biological; D008969:Molecular Sequence Data; D017570:MyoD Protein / Q000378:metabolism; D018008:Myogenin / Q000378:metabolism; D047495:PPAR gamma / Q000819:agonists / Q000378:metabolism; D017111:Phodopus; D011485:Protein Binding; D051381:Rats; D016329:Sp1 Transcription Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D051705:Sp3 Transcription Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000071247:Uncoupling Protein 3; D050880:p300-CBP Transcription Factors / Q000378:metabolism
chemical_list: D007473:Ion Channels; D024101:Mitochondrial Proteins; D017570:MyoD Protein; D018008:Myogenin; D047495:PPAR gamma; D016329:Sp1 Transcription Factor; C000604393:Ucp3 protein, mouse; C000604394:Ucp3 protein, rat; D000071247:Uncoupling Protein 3; D051705:Sp3 Transcription Factor; D004247:DNA; D050880:p300-CBP Transcription Factors