title: Activity-dependent Regulation of Histone Lysine Demethylase KDM1A by a Putative Thiol/Disulfide Switch.
abstract: Lysine demethylation of proteins such as histones is catalyzed by several classes of enzymes, including the FAD-dependent amine oxidases KDM1A/B. The KDM1 family is homologous to the mitochondrial monoamine oxidases MAO-A/B and produces hydrogen peroxide in the nucleus as a byproduct of demethylation. Here, we show KDM1A is highly thiol-reactive in vitro and in cellular models. Enzyme activity is potently and reversibly inhibited by the drug disulfiram and by hydrogen peroxide. Hydrogen peroxide produced by KDM1A catalysis reduces thiol labeling and inactivates demethylase activity over time. MALDI-TOF mass spectrometry indicates that hydrogen peroxide blocks labeling of cysteine 600, which we propose forms an intramolecular disulfide with cysteine 618 to negatively regulate the catalytic activity of KDM1A. This activity-dependent regulation is unique among histone-modifying enzymes but consistent with redox sensitivity of epigenetic regulators.
authors.affiliation: From the Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138,; the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, and; the Chemical Neurobiology Laboratory, Center for Human Genetic Research, Departments of Neurology & Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114.
authors.forename: Emily L
authors.initials: EL
authors.lastname: Ricq
authors.affiliation: the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, and.
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Hooker
authors.affiliation: the Chemical Neurobiology Laboratory, Center for Human Genetic Research, Departments of Neurology & Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114. Electronic address: shaggarty@mgh.harvard.edu.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Haggarty
mesh_terms: D003545:Cysteine / Q000737:chemistry / Q000378:metabolism; D004220:Disulfides / Q000737:chemistry; D004221:Disulfiram / Q000737:chemistry; D006367:HeLa Cells; D056466:Histone Demethylases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D004220:Disulfides; D013438:Sulfhydryl Compounds; D006861:Hydrogen Peroxide; D056466:Histone Demethylases; C495195:KDM1A protein, human; D003545:Cysteine; D004221:Disulfiram
keywords: chemical biology; disulfide; drug screening; enzyme inactivation; flavoprotein; histone demethylase; hydrogen peroxide; reactive oxygen species (ROS); redox regulation; thiol