1
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Alteen MG, Meek RW, Kolappan S, Busmann JA, Cao J, O’Gara Z, Chou Y, Derda R, Davies GJ, Vocadlo DJ. Phage display uncovers a sequence motif that drives polypeptide binding to a conserved regulatory exosite of O-GlcNAc transferase. Proc Natl Acad Sci U S A 2023; 120:e2303690120. [PMID: 37819980 PMCID: PMC10589721 DOI: 10.1073/pnas.2303690120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 08/29/2023] [Indexed: 10/13/2023] Open
Abstract
The modification of nucleocytoplasmic proteins by O-linked N-acetylglucosamine (O-GlcNAc) is an important regulator of cell physiology. O-GlcNAc is installed on over a thousand proteins by just one enzyme, O-GlcNAc transferase (OGT). How OGT is regulated is therefore a topic of interest. To gain insight into these questions, we used OGT to perform phage display selection from an unbiased library of ~109 peptides of 15 amino acids in length. Following rounds of selection and deep mutational panning, we identified a high-fidelity peptide consensus sequence, [Y/F]-x-P-x-Y-x-[I/M/F], that drives peptide binding to OGT. Peptides containing this sequence bind to OGT in the high nanomolar to low micromolar range and inhibit OGT in a noncompetitive manner with low micromolar potencies. X-ray structural analyses of OGT in complex with a peptide containing this motif surprisingly revealed binding to an exosite proximal to the active site of OGT. This structure defines the detailed molecular basis driving peptide binding and explains the need for specific residues within the sequence motif. Analysis of the human proteome revealed this motif within 52 nuclear and cytoplasmic proteins. Collectively, these data suggest a mode of regulation of OGT by which polypeptides can bind to this exosite to cause allosteric inhibition of OGT through steric occlusion of its active site. We expect that these insights will drive improved understanding of the regulation of OGT within cells and enable the development of new chemical tools to exert fine control over OGT activity.
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Affiliation(s)
- Matthew G. Alteen
- Department of Chemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Richard W. Meek
- York Structural Biology Laboratory, Department of Chemistry, University of York, YorkYO10 5DD, United Kingdom
- School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, SouthamptonSO17 1BJ, United Kingdom
| | - Subramania Kolappan
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Jil A. Busmann
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Jessica Cao
- 48 Hour Discovery, Nanotechnology Research Centre, Edmonton, ABT6G 2M9, Canada
| | - Zoe O’Gara
- 48 Hour Discovery, Nanotechnology Research Centre, Edmonton, ABT6G 2M9, Canada
| | - Ying Chou
- 48 Hour Discovery, Nanotechnology Research Centre, Edmonton, ABT6G 2M9, Canada
| | - Ratmir Derda
- 48 Hour Discovery, Nanotechnology Research Centre, Edmonton, ABT6G 2M9, Canada
- Department of Chemistry, University of Alberta, Edmonton, ABT6G 2G2, Canada
| | - Gideon J. Davies
- York Structural Biology Laboratory, Department of Chemistry, University of York, YorkYO10 5DD, United Kingdom
| | - David J. Vocadlo
- Department of Chemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
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2
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Abstract
O-GlcNAcylation is a dynamic post-translational modification performed by two opposing enzymes: O-GlcNAc transferase and O-GlcNAcase. O-GlcNAcylation is generally believed to act as a metabolic integrator in numerous signalling pathways. The stoichiometry of this modification is tightly controlled throughout all stages of development, with both hypo/hyper O-GlcNAcylation resulting in broad defects. In this Primer, we discuss the role of O-GlcNAcylation in developmental processes from stem cell maintenance and differentiation to cell and tissue morphogenesis.
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Affiliation(s)
- Ignacy Czajewski
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Daan M F van Aalten
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
- Institute of Molecular Precision Medicine, Xiangya Hospital, Central South University, Changsha 410000, China
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus 8000, Denmark
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3
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Wenzel DM, Olivier-Van Stichelen S. The O-GlcNAc cycling in neurodevelopment and associated diseases. Biochem Soc Trans 2022; 50:1693-1702. [PMID: 36383066 PMCID: PMC10462390 DOI: 10.1042/bst20220539] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 11/18/2022]
Abstract
Proper neuronal development is essential to growth and adult brain function. Alterations at any step of this highly organized sequence of events, due to genetic mutations or environmental factors, triggers brain malformations, which are leading causes of diseases including epilepsy, intellectual disabilities, and many others. The role of glycosylation in neuronal development has been emphasized for many years, notably in studying human congenital disorders of glycosylation (CDGs). These diseases highlight that genetic defects in glycosylation pathways are almost always associated with severe neurological abnormalities, suggesting that glycosylation plays an essential role in early brain development. Congenital disorders of O-GlcNAcylation are no exception, and all mutations of the O-GlcNAc transferase (OGT) are associated with X-linked intellectual disabilities (XLID). In addition, mouse models and in vitro mechanistic studies have reinforced the essential role of O-GlcNAcylation in neuronal development and signaling. In this review, we give an overview of the role of O-GlcNAcylation in this critical physiological process and emphasize the consequences of its dysregulation.
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Affiliation(s)
- Dawn M Wenzel
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, U.S.A
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4
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Structural insights into mechanism and specificity of the plant protein O-fucosyltransferase SPINDLY. Nat Commun 2022; 13:7424. [PMID: 36456586 PMCID: PMC9715652 DOI: 10.1038/s41467-022-35234-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/22/2022] [Indexed: 12/04/2022] Open
Abstract
Arabidopsis glycosyltransferase family 41 (GT41) protein SPINDLY (SPY) plays pleiotropic roles in plant development. Despite the amino acid sequence is similar to human O-GlcNAc transferase, Arabidopsis SPY has been identified as a novel nucleocytoplasmic protein O-fucosyltransferase. SPY-like proteins extensively exist in diverse organisms, indicating that O-fucosylation by SPY is a common way to regulate intracellular protein functions. However, the details of how SPY recognizes and glycosylates substrates are unknown. Here, we present a crystal structure of Arabidopsis SPY/GDP complex at 2.85 Å resolution. SPY adopts a head-to-tail dimer. Strikingly, the conformation of a 'catalytic SPY'/GDP/'substrate SPY' complex formed by two symmetry-related SPY dimers is captured in the crystal lattice. The structure together with mutagenesis and enzymatic data demonstrate SPY can fucosylate itself and SPY's self-fucosylation region negatively regulates its enzyme activity, reveal SPY's substrate recognition and enzyme mechanism, and provide insights into the glycan donor substrate selection in GT41 proteins.
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5
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Liu Y, Hu YJ, Fan WX, Quan X, Xu B, Li SZ. O-GlcNAcylation: The Underestimated Emerging Regulators of Skeletal Muscle Physiology. Cells 2022; 11:cells11111789. [PMID: 35681484 PMCID: PMC9180116 DOI: 10.3390/cells11111789] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
O-GlcNAcylation is a highly dynamic, reversible and atypical glycosylation that regulates the activity, biological function, stability, sublocation and interaction of target proteins. O-GlcNAcylation receives and coordinates different signal inputs as an intracellular integrator similar to the nutrient sensor and stress receptor, which target multiple substrates with spatio-temporal analysis specifically to maintain cellular homeostasis and normal physiological functions. Our review gives a brief description of O-GlcNAcylation and its only two processing enzymes and HBP flux, which will help to better understand its physiological characteristics of sensing nutrition and environmental cues. This nutritional and stress-sensitive properties of O-GlcNAcylation allow it to participate in the precise regulation of skeletal muscle metabolism. This review discusses the mechanism of O-GlcNAcylation to alleviate metabolic disorders and the controversy about the insulin resistance of skeletal muscle. The level of global O-GlcNAcylation is precisely controlled and maintained in the “optimal zone”, and its abnormal changes is a potential factor in the pathogenesis of cancer, neurodegeneration, diabetes and diabetic complications. Although the essential role of O-GlcNAcylation in skeletal muscle physiology has been widely studied and recognized, it still is underestimated and overlooked. This review highlights the latest progress and potential mechanisms of O-GlcNAcylation in the regulation of skeletal muscle contraction and structural properties.
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Affiliation(s)
| | | | | | | | - Bin Xu
- Correspondence: (B.X.); (S.-Z.L.)
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6
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Fenckova M, Muha V, Mariappa D, Catinozzi M, Czajewski I, Blok LER, Ferenbach AT, Storkebaum E, Schenck A, van Aalten DMF. Intellectual disability-associated disruption of O-GlcNAc cycling impairs habituation learning in Drosophila. PLoS Genet 2022; 18:e1010159. [PMID: 35500025 PMCID: PMC9140282 DOI: 10.1371/journal.pgen.1010159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 05/27/2022] [Accepted: 03/21/2022] [Indexed: 11/19/2022] Open
Abstract
O-GlcNAcylation is a reversible co-/post-translational modification involved in a multitude of cellular processes. The addition and removal of the O-GlcNAc modification is controlled by two conserved enzymes, O-GlcNAc transferase (OGT) and O-GlcNAc hydrolase (OGA). Mutations in OGT have recently been discovered to cause a novel Congenital Disorder of Glycosylation (OGT-CDG) that is characterized by intellectual disability. The mechanisms by which OGT-CDG mutations affect cognition remain unclear. We manipulated O-GlcNAc transferase and O-GlcNAc hydrolase activity in Drosophila and demonstrate an important role of O-GlcNAcylation in habituation learning and synaptic development at the larval neuromuscular junction. Introduction of patient-specific missense mutations into Drosophila O-GlcNAc transferase using CRISPR/Cas9 gene editing leads to deficits in locomotor function and habituation learning. The habituation deficit can be corrected by blocking O-GlcNAc hydrolysis, indicating that OGT-CDG mutations affect cognition-relevant habituation via reduced protein O-GlcNAcylation. This study establishes a critical role for O-GlcNAc cycling and disrupted O-GlcNAc transferase activity in cognitive dysfunction, and suggests that blocking O-GlcNAc hydrolysis is a potential strategy to treat OGT-CDG.
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Affiliation(s)
- Michaela Fenckova
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
| | - Villo Muha
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Daniel Mariappa
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Marica Catinozzi
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour, Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Ignacy Czajewski
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Laura E. R. Blok
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
| | - Andrew T. Ferenbach
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Erik Storkebaum
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour, Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Annette Schenck
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
| | - Daan M. F. van Aalten
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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7
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Abstract
Post-translational modification with O-linked β-N-acetylglucosamine (O-GlcNAc), a process referred to as O-GlcNAcylation, occurs on a vast variety of proteins. Mounting evidence in the past several decades has clearly demonstrated that O-GlcNAcylation is a unique and ubiquitous modification. Reminiscent of a code, protein O-GlcNAcylation functions as a crucial regulator of nearly all cellular processes studied. The primary aim of this review is to summarize the developments in our understanding of myriad protein substrates modified by O-GlcNAcylation from a systems perspective. Specifically, we provide a comprehensive survey of O-GlcNAcylation in multiple species studied, including eukaryotes (e.g., protists, fungi, plants, Caenorhabditis elegans, Drosophila melanogaster, murine, and human), prokaryotes, and some viruses. We evaluate features (e.g., structural properties and sequence motifs) of O-GlcNAc modification on proteins across species. Given that O-GlcNAcylation functions in a species-, tissue-/cell-, protein-, and site-specific manner, we discuss the functional roles of O-GlcNAcylation on human proteins. We focus particularly on several classes of relatively well-characterized human proteins (including transcription factors, protein kinases, protein phosphatases, and E3 ubiquitin-ligases), with representative O-GlcNAc site-specific functions presented. We hope the systems view of the great endeavor in the past 35 years will help demystify the O-GlcNAc code and lead to more fascinating studies in the years to come.
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Affiliation(s)
- Junfeng Ma
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
| | - Chunyan Hou
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
| | - Ci Wu
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
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8
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Mammalian cell proliferation requires noncatalytic functions of O-GlcNAc transferase. Proc Natl Acad Sci U S A 2021; 118:2016778118. [PMID: 33419956 DOI: 10.1073/pnas.2016778118] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
O-GlcNAc transferase (OGT), found in the nucleus and cytoplasm of all mammalian cell types, is essential for cell proliferation. Why OGT is required for cell growth is not known. OGT performs two enzymatic reactions in the same active site. In one, it glycosylates thousands of different proteins, and in the other, it proteolytically cleaves another essential protein involved in gene expression. Deconvoluting OGT's myriad cellular roles has been challenging because genetic deletion is lethal; complementation methods have not been established. Here, we developed approaches to replace endogenous OGT with separation-of-function variants to investigate the importance of OGT's enzymatic activities for cell viability. Using genetic complementation, we found that OGT's glycosyltransferase function is required for cell growth but its protease function is dispensable. We next used complementation to construct a cell line with degron-tagged wild-type OGT. When OGT was degraded to very low levels, cells stopped proliferating but remained viable. Adding back catalytically inactive OGT rescued growth. Therefore, OGT has an essential noncatalytic role that is necessary for cell proliferation. By developing a method to quantify how OGT's catalytic and noncatalytic activities affect protein abundance, we found that OGT's noncatalytic functions often affect different proteins from its catalytic functions. Proteins involved in oxidative phosphorylation and the actin cytoskeleton were especially impacted by the noncatalytic functions. We conclude that OGT integrates both catalytic and noncatalytic functions to control cell physiology.
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9
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Morino K, Maegawa H. Role of O-linked N-acetylglucosamine in the homeostasis of metabolic organs, and its potential links with diabetes and its complications. J Diabetes Investig 2021; 12:130-136. [PMID: 32654398 PMCID: PMC7858115 DOI: 10.1111/jdi.13359] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/07/2020] [Accepted: 07/09/2020] [Indexed: 12/12/2022] Open
Abstract
Recent studies using genetically manipulated mouse models have shown the pivotal role of O-linked N-acetylglucosamine modification (O-GlcNAcylation) in the metabolism of multiple organs. The molecular mechanism involves the sensing of glucose flux by the hexosamine biosynthesis pathway, which leads to the adjustment of cellular metabolism to protect against changes in the environment of each organ through O-GlcNAcylation. More recently, not only glucose, but also fluxes of amino acids and fatty acids have been reported to induce O-GlcNAcylation, affecting multiple cellular processes. In this review, we discuss how O-GlcNAcylation maintains homeostasis in organs that are affected by diabetes mellitus: skeletal muscle, adipose tissue, liver and pancreatic β-cells. Furthermore, we discuss the importance of O-GlcNAcylation in the pathogenesis of diabetic complications. By elucidating the molecular mechanisms whereby cellular homeostasis is maintained, despite changes in metabolic flux, these studies might provide new targets for the treatment and prevention of diabetes and its complications.
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Affiliation(s)
- Katsutaro Morino
- Division of Diabetology, Endocrinology, and NephrologyDepartment of MedicineShiga University of Medical ScienceOtsuShigaJapan
| | - Hiroshi Maegawa
- Division of Diabetology, Endocrinology, and NephrologyDepartment of MedicineShiga University of Medical ScienceOtsuShigaJapan
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10
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Pravata VM, Gundogdu M, Bartual SG, Ferenbach AT, Stavridis M, Õunap K, Pajusalu S, Žordania R, Wojcik MH, van Aalten DMF. A missense mutation in the catalytic domain of O-GlcNAc transferase links perturbations in protein O-GlcNAcylation to X-linked intellectual disability. FEBS Lett 2019; 594:717-727. [PMID: 31627256 PMCID: PMC7042088 DOI: 10.1002/1873-3468.13640] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 06/25/2019] [Accepted: 10/07/2019] [Indexed: 01/01/2023]
Abstract
X‐linked intellectual disabilities (XLID) are common developmental disorders. The enzyme O‐GlcNAc transferase encoded by OGT, a recently discovered XLID gene, attaches O‐GlcNAc to nuclear and cytoplasmic proteins. As few missense mutations have been described, it is unclear what the aetiology of the patient phenotypes is. Here, we report the discovery of a missense mutation in the catalytic domain of OGT in an XLID patient. X‐ray crystallography reveals that this variant leads to structural rearrangements in the catalytic domain. The mutation reduces in vitro OGT activity on substrate peptides/protein. Mouse embryonic stem cells carrying the mutation reveal reduced O‐GlcNAcase (OGA) and global O‐GlcNAc levels. These data suggest a direct link between changes in the O‐GlcNAcome and intellectual disability observed in patients carrying OGT mutations.
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Affiliation(s)
- Veronica M Pravata
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, UK
| | - Mehmet Gundogdu
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, UK
| | - Sergio G Bartual
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, UK
| | - Andrew T Ferenbach
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, UK
| | - Marios Stavridis
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, UK
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Estonia
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Estonia
| | - Riina Žordania
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Estonia
| | - Monica H Wojcik
- Divisions of Newborn Medicine and Genetics and Genomics, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Daan M F van Aalten
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, UK
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11
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Early life exposure of a biocide, CMIT/MIT causes metabolic toxicity via the O-GlcNAc transferase pathway in the nematode C. elegans. Toxicol Appl Pharmacol 2019; 376:1-8. [PMID: 31100289 DOI: 10.1016/j.taap.2019.05.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/28/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
Unusual cases of fatal lung injury, later determined to be a result of exposure to chemicals used as humidifier disinfectants, were reported among Korean children from 2006 to 2011. This resulted in considerable study of the pulmonary toxicity of humidifier disinfectant chemicals to establish the causal relationship between exposure and lung disease. However, the systemic toxicity of the former and health effects other than lung disease are not fully understood. Here, we investigated the effect of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazolin-3-one (CMIT/MIT), among the humidifier disinfectants used in the accidents, on the development of metabolic toxicity in the model organism, Caenorhabditis elegans using an exposure scenario comparison. We screened the potential of CMIT/MIT to induce metabolic toxicity using C. elegans oga-1(ok1207) and ogt-1(ok1474) mutants. We also performed a pathway analysis based on C. elegans transcription factor RNAi library screening to identify the underlying toxicity mechanisms. Finally, to understand the critical window of exposure for metabolic toxicity, responses to exposure during different periods in the life cycles of the worms were compared. We determined that CMIT/MIT could induce metabolic toxicity through O-linked N-acetylglucosamine transferase and early life seems to be the critical window for exposure for metabolic toxicity for this substance. The O-linked N-acetylglucosamine transferase pathway is conserved from worms to humans; our results thus insinuate that early-life exposure to CMIT/MIT could cause metabolic health problems during adult life in humans. We therefore suggest that a systemic toxicity approach should be considered to comprehensively understand the adverse health effects of humidifier disinfectant misuse.
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12
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Pravata VM, Muha V, Gundogdu M, Ferenbach AT, Kakade PS, Vandadi V, Wilmes AC, Borodkin VS, Joss S, Stavridis MP, van Aalten DMF. Catalytic deficiency of O-GlcNAc transferase leads to X-linked intellectual disability. Proc Natl Acad Sci U S A 2019; 116:14961-14970. [PMID: 31296563 PMCID: PMC6660750 DOI: 10.1073/pnas.1900065116] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
O-GlcNAc transferase (OGT) is an X-linked gene product that is essential for normal development of the vertebrate embryo. It catalyses the O-GlcNAc posttranslational modification of nucleocytoplasmic proteins and proteolytic maturation of the transcriptional coregulator Host cell factor 1 (HCF1). Recent studies have suggested that conservative missense mutations distal to the OGT catalytic domain lead to X-linked intellectual disability in boys, but it is not clear if this is through changes in the O-GlcNAc proteome, loss of protein-protein interactions, or misprocessing of HCF1. Here, we report an OGT catalytic domain missense mutation in monozygotic female twins (c. X:70779215 T > A, p. N567K) with intellectual disability that allows dissection of these effects. The patients show limited IQ with developmental delay and skewed X-inactivation. Molecular analyses revealed decreased OGT stability and disruption of the substrate binding site, resulting in loss of catalytic activity. Editing this mutation into the Drosophila genome results in global changes in the O-GlcNAc proteome, while in mouse embryonic stem cells it leads to loss of O-GlcNAcase and delayed differentiation down the neuronal lineage. These data imply that catalytic deficiency of OGT could contribute to X-linked intellectual disability.
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Affiliation(s)
- Veronica M Pravata
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Villo Muha
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Mehmet Gundogdu
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Andrew T Ferenbach
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Poonam S Kakade
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Vasudha Vandadi
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Ariane C Wilmes
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Vladimir S Borodkin
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Shelagh Joss
- West of Scotland Genetic Service, Queen Elizabeth University Hospital, G51 4TF Glasgow, United Kingdom
| | - Marios P Stavridis
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom
| | - Daan M F van Aalten
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, United Kingdom;
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13
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Giles AC, Desbois M, Opperman KJ, Tavora R, Maroni MJ, Grill B. A complex containing the O-GlcNAc transferase OGT-1 and the ubiquitin ligase EEL-1 regulates GABA neuron function. J Biol Chem 2019; 294:6843-6856. [PMID: 30858176 DOI: 10.1074/jbc.ra119.007406] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/07/2019] [Indexed: 12/16/2022] Open
Abstract
Inhibitory GABAergic transmission is required for proper circuit function in the nervous system. However, our understanding of molecular mechanisms that preferentially influence GABAergic transmission, particularly presynaptic mechanisms, remains limited. We previously reported that the ubiquitin ligase EEL-1 preferentially regulates GABAergic presynaptic transmission. To further explore how EEL-1 functions, here we performed affinity purification proteomics using Caenorhabditis elegans and identified the O-GlcNAc transferase OGT-1 as an EEL-1 binding protein. This observation was intriguing, as we know little about how OGT-1 affects neuron function. Using C. elegans biochemistry, we confirmed that the OGT-1/EEL-1 complex forms in neurons in vivo and showed that the human orthologs, OGT and HUWE1, also bind in cell culture. We observed that, like EEL-1, OGT-1 is expressed in GABAergic motor neurons, localizes to GABAergic presynaptic terminals, and functions cell-autonomously to regulate GABA neuron function. Results with catalytically inactive point mutants indicated that OGT-1 glycosyltransferase activity is dispensable for GABA neuron function. Consistent with OGT-1 and EEL-1 forming a complex, genetic results using automated, behavioral pharmacology assays showed that ogt-1 and eel-1 act in parallel to regulate GABA neuron function. These findings demonstrate that OGT-1 and EEL-1 form a conserved signaling complex and function together to affect GABA neuron function.
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Affiliation(s)
- Andrew C Giles
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Muriel Desbois
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Karla J Opperman
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Rubens Tavora
- the Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida 33458
| | - Marissa J Maroni
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Brock Grill
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
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14
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Decourcelle A, Leprince D, Dehennaut V. Regulation of Polycomb Repression by O-GlcNAcylation: Linking Nutrition to Epigenetic Reprogramming in Embryonic Development and Cancer. Front Endocrinol (Lausanne) 2019; 10:117. [PMID: 30873122 PMCID: PMC6400832 DOI: 10.3389/fendo.2019.00117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 02/08/2019] [Indexed: 11/25/2022] Open
Abstract
Epigenetic modifications are major actors of early embryogenesis and carcinogenesis and are sensitive to nutritional environment. In recent years, the nutritional sensor O-GlcNAcylation has been recognized as a key regulator of chromatin remodeling. In this review, we summarize and discuss recent clues that OGT and O-GlcNAcylation intimately regulate the functions of the Polycomb group proteins at different levels especially during Drosophila melanogaster embryonic development and in human cancer cell lines. These observations define an additional connection between nutrition and epigenetic reprogramming associated to embryonic development and cancer.
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15
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Selvan N, George S, Serajee FJ, Shaw M, Hobson L, Kalscheuer V, Prasad N, Levy SE, Taylor J, Aftimos S, Schwartz CE, Huq AM, Gecz J, Wells L. O-GlcNAc transferase missense mutations linked to X-linked intellectual disability deregulate genes involved in cell fate determination and signaling. J Biol Chem 2018; 293:10810-10824. [PMID: 29769320 DOI: 10.1074/jbc.ra118.002583] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/27/2018] [Indexed: 01/17/2023] Open
Abstract
It is estimated that ∼1% of the world's population has intellectual disability, with males affected more often than females. OGT is an X-linked gene encoding for the enzyme O-GlcNAc transferase (OGT), which carries out the reversible addition of N-acetylglucosamine (GlcNAc) to Ser/Thr residues of its intracellular substrates. Three missense mutations in the tetratricopeptide (TPR) repeats of OGT have recently been reported to cause X-linked intellectual disability (XLID). Here, we report the discovery of two additional novel missense mutations (c.775 G>A, p.A259T, and c.1016 A>G, p.E339G) in the TPR domain of OGT that segregate with XLID in affected families. Characterization of all five of these XLID missense variants of OGT demonstrates modest declines in thermodynamic stability and/or activities of the variants. We engineered each of the mutations into a male human embryonic stem cell line using CRISPR/Cas9. Investigation of the global O-GlcNAc profile as well as OGT and O-GlcNAc hydrolase levels by Western blotting showed no gross changes in steady-state levels in the engineered lines. However, analyses of the differential transcriptomes of the OGT variant-expressing stem cells revealed shared deregulation of genes involved in cell fate determination and liver X receptor/retinoid X receptor signaling, which has been implicated in neuronal development. Thus, here we reveal two additional mutations encoding residues in the TPR regions of OGT that appear causal for XLID and provide evidence that the relatively stable and active TPR variants may share a common, unelucidated mechanism of altering gene expression profiles in human embryonic stem cells.
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Affiliation(s)
- Nithya Selvan
- From the Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Stephan George
- From the Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Fatema J Serajee
- the Departments of Pediatrics and of Neurology, Wayne State University, Detroit, Michigan 48201
| | - Marie Shaw
- the Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide South Australia 5006, Australia
| | - Lynne Hobson
- the Women's and Children's Hospital, North Adelaide, South Australia 5006, Australia
| | - Vera Kalscheuer
- the Research Group Development and Disease, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Nripesh Prasad
- the Genomic Services Laboratory, HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806
| | - Shawn E Levy
- the Genomic Services Laboratory, HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806
| | - Juliet Taylor
- the Genetic Health Services New Zealand-Northern Hub, Auckland City Hospital, Auckland 1142, New Zealand
| | - Salim Aftimos
- the Genetic Health Services New Zealand-Northern Hub, Auckland City Hospital, Auckland 1142, New Zealand
| | | | - Ahm M Huq
- the Departments of Pediatrics and of Neurology, Wayne State University, Detroit, Michigan 48201
| | - Jozef Gecz
- the Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide South Australia 5006, Australia.,the South Australian Health and Medical Research Institute, Adelaide, South Australia 5006, Australia
| | - Lance Wells
- From the Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602,
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16
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Mariappa D, Ferenbach AT, van Aalten DMF. Effects of hypo- O-GlcNAcylation on Drosophila development. J Biol Chem 2018; 293:7209-7221. [PMID: 29588363 PMCID: PMC5950000 DOI: 10.1074/jbc.ra118.002580] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 03/21/2018] [Indexed: 01/12/2023] Open
Abstract
Post-translational modification of serine/threonine residues in nucleocytoplasmic proteins with GlcNAc (O-GlcNAcylation) is an essential regulatory mechanism in many cellular processes. In Drosophila, null mutants of the Polycomb gene O-GlcNAc transferase (OGT; also known as super sex combs (sxc)) display homeotic phenotypes. To dissect the requirement for O-GlcNAc signaling in Drosophila development, we used CRISPR/Cas9 gene editing to generate rationally designed sxc catalytically hypomorphic or null point mutants. Of the fertile males derived from embryos injected with the CRISPR/Cas9 reagents, 25% produced progeny carrying precise point mutations with no detectable off-target effects. One of these mutants, the catalytically inactive sxcK872M, was recessive lethal, whereas a second mutant, the hypomorphic sxcH537A, was homozygous viable. We observed that reduced total protein O-GlcNAcylation in the sxcH537A mutant is associated with a wing vein phenotype and temperature-dependent lethality. Genetic interaction between sxcH537A and a null allele of Drosophila host cell factor (dHcf), encoding an extensively O-GlcNAcylated transcriptional coactivator, resulted in abnormal scutellar bristle numbers. A similar phenotype was also observed in sxcH537A flies lacking a copy of skuld (skd), a Mediator complex gene known to affect scutellar bristle formation. Interestingly, this phenotype was independent of OGT Polycomb function or dHcf downstream targets. In conclusion, the generation of the endogenous OGT hypomorphic mutant sxcH537A enabled us to identify pleiotropic effects of globally reduced protein O-GlcNAc during Drosophila development. The mutants generated and phenotypes observed in this study provide a platform for discovery of OGT substrates that are critical for Drosophila development.
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Affiliation(s)
- Daniel Mariappa
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom.
| | - Andrew T Ferenbach
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom
| | - Daan M F van Aalten
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom.
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17
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Britto-Borges T, Barton GJ. A study of the structural properties of sites modified by the O-linked 6-N-acetylglucosamine transferase. PLoS One 2017; 12:e0184405. [PMID: 28886091 PMCID: PMC5590929 DOI: 10.1371/journal.pone.0184405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 08/23/2017] [Indexed: 01/17/2023] Open
Abstract
Protein O-GlcNAcylation (O-GlcNAc) is an essential post-translational modification (PTM) in higher eukaryotes. The O-linked β-N-acetylglucosamine transferase (OGT), targets specific Serines and Threonines (S/T) in intracellular proteins. However, unlike phosphorylation, fewer than 25% of known O-GlcNAc sites match a clear sequence pattern. Accordingly, the three-dimensional structures of O-GlcNAc sites were characterised to investigate the role of structure in molecular recognition. From 1,584 O-GlcNAc sites in 620 proteins, 143 were mapped to protein structures determined by X-ray crystallography. The modified S/T were 1.7 times more likely to be annotated in the REM465 field which defines missing residues in a protein structure, while 7 O-GlcNAc sites were solvent inaccessible and unlikely to be targeted by OGT. 132 sites with complete backbone atoms clustered into 10 groups, but these were indistinguishable from clusters from unmodified S/T. This suggests there is no prevalent three-dimensional motif for OGT recognition. Predicted features from the 620 proteins were compared to unmodified S/T in O-GlcNAcylated proteins and globular proteins. The Jpred4 predicted secondary structure shows that modified S/T were more likely to be coils. 5/6 methods to predict intrinsic disorder indicated O-GlcNAcylated S/T to be significantly more disordered than unmodified S/T. Although the analysis did not find a pattern in the site three-dimensional structure, it revealed the residues around the modification site are likely to be disordered and suggests a potential role of secondary structure elements in OGT site recognition.
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Affiliation(s)
- Thiago Britto-Borges
- Division of Computational Biology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Geoffrey J. Barton
- Division of Computational Biology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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18
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Willems AP, Gundogdu M, Kempers MJE, Giltay JC, Pfundt R, Elferink M, Loza BF, Fuijkschot J, Ferenbach AT, van Gassen KLI, van Aalten DMF, Lefeber DJ. Mutations in N-acetylglucosamine ( O-GlcNAc) transferase in patients with X-linked intellectual disability. J Biol Chem 2017; 292:12621-12631. [PMID: 28584052 PMCID: PMC5535036 DOI: 10.1074/jbc.m117.790097] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 05/23/2017] [Indexed: 11/30/2022] Open
Abstract
N-Acetylglucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential and dynamic post-translational modification. The O-GlcNAc modification is present on numerous nuclear and cytosolic proteins and has been implicated in essential cellular functions such as signaling and gene expression. Accordingly, altered levels of protein O-GlcNAcylation have been associated with developmental defects and neurodegeneration. However, mutations in the OGT gene have not yet been functionally confirmed in humans. Here, we report on two hemizygous mutations in OGT in individuals with X-linked intellectual disability (XLID) and dysmorphic features: one missense mutation (p.Arg284Pro) and one mutation leading to a splicing defect (c.463–6T>G). Both mutations reside in the tetratricopeptide repeats of OGT that are essential for substrate recognition. We observed slightly reduced levels of OGT protein and reduced levels of its opposing enzyme O-GlcNAcase in both patient-derived fibroblasts, but global O-GlcNAc levels appeared to be unaffected. Our data suggest that mutant cells attempt to maintain global O-GlcNAcylation by down-regulating O-GlcNAcase expression. We also found that the c.463–6T>G mutation leads to aberrant mRNA splicing, but no stable truncated protein was detected in the corresponding patient-derived fibroblasts. Recombinant OGT bearing the p.Arg284Pro mutation was prone to unfolding and exhibited reduced glycosylation activity against a complex array of glycosylation substrates and proteolytic processing of the transcription factor host cell factor 1, which is also encoded by an XLID-associated gene. We conclude that defects in O-GlcNAc homeostasis and host cell factor 1 proteolysis may play roles in mediation of XLID in individuals with OGT mutations.
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Affiliation(s)
- Anke P Willems
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Mehmet Gundogdu
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, United Kingdom
| | - Marlies J E Kempers
- Department of Genetics, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Jacques C Giltay
- Department of Genetics, University Medical Centre Utrecht, 3508 AB Utrecht, The Netherlands
| | - Rolph Pfundt
- Department of Genetics, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Martin Elferink
- Department of Genetics, University Medical Centre Utrecht, 3508 AB Utrecht, The Netherlands
| | - Bettina F Loza
- Department of Paediatrics, VieCuri Hospital, 5900 BX Venlo, The Netherlands
| | - Joris Fuijkschot
- Department of Paediatrics, Radboud University Medical Centre and Amalia Children's Hospital, 6500 HB Nijmegen, The Netherlands
| | - Andrew T Ferenbach
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, United Kingdom
| | - Koen L I van Gassen
- Department of Genetics, University Medical Centre Utrecht, 3508 AB Utrecht, The Netherlands
| | - Daan M F van Aalten
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, United Kingdom.
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
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19
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Levine ZG, Walker S. The Biochemistry of O-GlcNAc Transferase: Which Functions Make It Essential in Mammalian Cells? Annu Rev Biochem 2017; 85:631-57. [PMID: 27294441 DOI: 10.1146/annurev-biochem-060713-035344] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
O-linked N-acetylglucosamine transferase (OGT) is found in all metazoans and plays an important role in development but at the single-cell level is only essential in dividing mammalian cells. Postmitotic mammalian cells and cells of invertebrates such as Caenorhabditis elegans and Drosophila can survive without copies of OGT. Why OGT is required in dividing mammalian cells but not in other cells remains unknown. OGT has multiple biochemical activities. Beyond its well-known role in adding β-O-GlcNAc to serine and threonine residues of nuclear and cytoplasmic proteins, OGT also acts as a protease in the maturation of the cell cycle regulator host cell factor 1 (HCF-1) and serves as an integral member of several protein complexes, many of them linked to gene expression. In this review, we summarize current understanding of the mechanisms underlying OGT's biochemical activities and address whether known functions of OGT could be related to its essential role in dividing mammalian cells.
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Affiliation(s)
- Zebulon G Levine
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts 02115; ,
| | - Suzanne Walker
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts 02115; ,
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20
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Genome-wide chemical mapping of O-GlcNAcylated proteins in Drosophila melanogaster. Nat Chem Biol 2016; 13:161-167. [PMID: 27918560 DOI: 10.1038/nchembio.2247] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 09/15/2016] [Indexed: 12/28/2022]
Abstract
N-Acetylglucosamine β-O-linked to nucleocytoplasmic proteins (O-GlcNAc) is implicated in the regulation of gene expression in organisms, from humans to Drosophila melanogaster. Within Drosophila, O-GlcNAc transferase (OGT) is one of the Polycomb group proteins (PcGs) that act through Polycomb group response elements (PREs) to silence homeotic (HOX) and other PcG target genes. Using Drosophila, we identify new O-GlcNAcylated PcG proteins and develop an antibody-free metabolic feeding approach to chemoselectively map genomic loci enriched in O-GlcNAc using next-generation sequencing. We find that O-GlcNAc is distributed to specific genomic loci both in cells and in vivo. Many of these loci overlap with PREs, but O-GlcNAc is also present at other loci lacking PREs. Loss of OGT leads to altered gene expression not only at loci containing PREs but also at loci lacking PREs, including several heterochromatic genes. These data suggest that O-GlcNAc acts through multiple mechanisms to regulate gene expression in Drosophila.
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21
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Hardivillé S, Hart GW. Nutrient regulation of gene expression by O-GlcNAcylation of chromatin. Curr Opin Chem Biol 2016; 33:88-94. [PMID: 27322399 DOI: 10.1016/j.cbpa.2016.06.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/31/2016] [Accepted: 06/01/2016] [Indexed: 12/25/2022]
Abstract
O-GlcNAcylation is a dynamic post-translational modification that is responsive to nutrient availably via the hexosamine biosynthetic pathway and its endproduct UDP-GlcNAc. O-GlcNAcylation serves as a nutrient sensor to regulate the activities of many proteins involved in nearly all biological processes. Within the last decade, OGT, OGA and O-GlcNAcylation have been shown to be at the nexus of epigenetic marks controlling gene expression during embryonic development, cell differentiation, in the maintenance of epigenetic states and in the etiology of epigenetic related diseases. OGT O-GlcNAcylates histones and epigenetic writers/erasers, and regulates gene activation, as well as gene repression. Here, we highlight recent work documenting the important roles O-GlcNAcylation and its cycling enzymes play in the nutrient regulation of epigenetic partners controlling gene expression.
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Affiliation(s)
- Stéphan Hardivillé
- Department of Biological Chemistry, Johns Hopkins University, School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205-2185, USA.
| | - Gerald W Hart
- Department of Biological Chemistry, Johns Hopkins University, School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205-2185, USA.
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