title: O-GlcNAcomic Profiling Identifies Widespread O-Linked β-N-Acetylglucosamine Modification (O-GlcNAcylation) in Oxidative Phosphorylation System Regulating Cardiac Mitochondrial Function.
abstract: Dynamic cycling of O-linked β-N-acetylglucosamine (O-GlcNAc) on nucleocytoplasmic proteins serves as a nutrient sensor to regulate numerous biological processes. However, mitochondrial protein O-GlcNAcylation and its effects on function are largely unexplored. In this study, we performed a comparative analysis of the proteome and O-GlcNAcome of cardiac mitochondria from rats acutely (12 h) treated without or with thiamet-G (TMG), a potent and specific inhibitor of O-GlcNAcase. We then determined the functional consequences in mitochondria isolated from the two groups. O-GlcNAcomic profiling finds that over 88 mitochondrial proteins are O-GlcNAcylated, with the oxidative phosphorylation system as a major target. Moreover, in comparison with controls, cardiac mitochondria from TMG-treated rats did not exhibit altered protein abundance but showed overall elevated O-GlcNAcylation of many proteins. However, O-GlcNAc was unexpectedly down-regulated at certain sites of specific proteins. Concomitantly, TMG treatment resulted in significantly increased mitochondrial oxygen consumption rates, ATP production rates, and enhanced threshold for permeability transition pore opening by Ca(2+). Our data reveal widespread and dynamic mitochondrial protein O-GlcNAcylation, serving as a regulator to their function.
authors.affiliation: From the Department of Biological Chemistry and.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Ma
authors.affiliation: Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.affiliation: Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: An-Chi
authors.initials: AC
authors.lastname: Wei
authors.affiliation: From the Department of Biological Chemistry and.
authors.forename: Partha
authors.initials: P
authors.lastname: Banerjee
authors.affiliation: Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Brian
authors.initials: B
authors.lastname: O'Rourke
authors.affiliation: From the Department of Biological Chemistry and gwhart@jhmi.edu.
authors.forename: Gerald W
authors.initials: GW
authors.lastname: Hart
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000378:metabolism; D054794:Glycomics; D006321:Heart / Q000502:physiology; D008297:Male; D013058:Mass Spectrometry; D008564:Membrane Potentials; D008929:Mitochondria, Heart / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins / Q000378:metabolism; D000083162:Mitochondrial Permeability Transition Pore; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D010085:Oxidative Phosphorylation; D010100:Oxygen / Q000378:metabolism*; D010539:Permeability; D020543:Proteome; D040901:Proteomics; D011714:Pyrans / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D053719:Tandem Mass Spectrometry; D013844:Thiazoles / Q000737:chemistry
chemical_list: D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D024101:Mitochondrial Proteins; D020543:Proteome; D011714:Pyrans; D013844:Thiazoles; C572247:thiamet G; D000255:Adenosine Triphosphate; D010100:Oxygen; D002118:Calcium; D000117:Acetylglucosamine
keywords: O-GlcNAcylation; O-linked N-acetylglucosamine (O-GlcNAc); glycomics; mass spectrometry (MS); mitochondria; oxidative phosphorylation; post-translational modification (PTM); proteomics