title: GADD45a physically and functionally interacts with TET1.
abstract: DNA demethylation plays a central role during development and in adult physiology. Different mechanisms of active DNA demethylation have been established. For example, Growth Arrest and DNA Damage 45-(GADD45) and Ten-Eleven-Translocation (TET) proteins act in active DNA demethylation but their functional relationship is unresolved. Here we show that GADD45a physically interacts--and functionally cooperates with TET1 in methylcytosine (mC) processing. In reporter demethylation GADD45a requires endogenous TET1 and conversely TET1 requires GADD45a. On GADD45a target genes TET1 hyperinduces 5-hydroxymethylcytosine (hmC) in the presence of GADD45a, while 5-formyl-(fC) and 5-carboxylcytosine (caC) are reduced. Likewise, in global analysis GADD45a positively regulates TET1 mediated mC oxidation and enhances fC/caC removal. Our data suggest a dual function of GADD45a in oxidative DNA demethylation, to promote directly or indirectly TET1 activity and to enhance subsequent fC/caC removal.
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kienhöfer
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany.
authors.forename: Michael U
authors.initials: MU
authors.lastname: Musheev
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Stapf
authors.affiliation: Johannes Gutenberg Universität Mainz, Institut für Pharmazie und Biochemie, 55128 Mainz, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: Helm
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Schomacher
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany; DKFZ-ZMBH Alliance, Division of Molecular Embryology, 69120 Heidelberg, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Niehrs
authors.affiliation: Institute of Molecular Biology, 55128 Mainz, Germany. Electronic address: A.Schaefer@imb-mainz.de.
authors.forename: Andrea
authors.initials: A
authors.lastname: Schäfer
mesh_terms: D044503:5-Methylcytosine / Q000378:metabolism / Q000031:analogs & derivatives; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D003596:Cytosine / Q000031:analogs & derivatives* / Q000378:metabolism; D019175:DNA Methylation / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006801:Humans; D047468:Immunoprecipitation; D006899:Mixed Function Oxygenases; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D000097642:GADD45 Proteins
chemical_list: D044503:5-Methylcytosine; D018797:Cell Cycle Proteins; D003596:Cytosine; D004268:DNA-Binding Proteins; D006899:Mixed Function Oxygenases; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; C560974:5-carboxylcytosine; C560973:5-formylcytosine; C439070:GADD45A protein, human; D000097642:GADD45 Proteins; C011865:5-hydroxymethylcytosine; C462539:TET1 protein, human
keywords: DNA demethylation; Gadd45; LC–MS/MS; TET; hmC