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Potter SC, Gibbs BE, Hammel FA, Joiner CM, Paulo JA, Janetzko J, Levine ZG, Fei GQ, Haggarty SJ, Walker S. Dissecting OGT's TPR domain to identify determinants of cellular function. Proc Natl Acad Sci U S A 2024; 121:e2401729121. [PMID: 38768345 PMCID: PMC11145291 DOI: 10.1073/pnas.2401729121] [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: 02/03/2024] [Accepted: 04/22/2024] [Indexed: 05/22/2024] Open
Abstract
O-GlcNAc transferase (OGT) is an essential mammalian enzyme that glycosylates myriad intracellular proteins and cleaves the transcriptional coregulator Host Cell Factor 1 to regulate cell cycle processes. Via these catalytic activities as well as noncatalytic protein-protein interactions, OGT maintains cell homeostasis. OGT's tetratricopeptide repeat (TPR) domain is important in substrate recognition, but there is little information on how changing the TPR domain impacts its cellular functions. Here, we investigate how altering OGT's TPR domain impacts cell growth after the endogenous enzyme is deleted. We find that disrupting the TPR residues required for OGT dimerization leads to faster cell growth, whereas truncating the TPR domain slows cell growth. We also find that OGT requires eight of its 13 TPRs to sustain cell viability. OGT-8, like the nonviable shorter OGT variants, is mislocalized and has reduced Ser/Thr glycosylation activity; moreover, its interactions with most of wild-type OGT's binding partners are broadly attenuated. Therefore, although OGT's five N-terminal TPRs are not essential for cell viability, they are required for proper subcellular localization and for mediating many of OGT's protein-protein interactions. Because the viable OGT truncation variant we have identified preserves OGT's essential functions, it may facilitate their identification.
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Affiliation(s)
- Sarah C. Potter
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
- Chemical Neurobiology Laboratory, Center for Genomic Medicine, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA02114
| | - Bettine E. Gibbs
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - Forrest A. Hammel
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - Cassandra M. Joiner
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - Joao A. Paulo
- Department of Cell Biology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - John Janetzko
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA02138
| | - Zebulon G. Levine
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - George Q. Fei
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
| | - Stephen J. Haggarty
- Chemical Neurobiology Laboratory, Center for Genomic Medicine, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA02114
| | - Suzanne Walker
- Department of Microbiology, Blavatnik Institute of Harvard Medical School, Boston, MA02115
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2
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Vang S, Helton ES, Guo Y, Burpee B, Rose E, Easter M, Bollenbecker S, Hirsch MJ, Matthews EL, Jones LI, Howze PH, Rajasekaran V, Denson R, Cochran P, Attah IK, Olson H, Clair G, Melkani G, Krick S, Barnes JW. O-GlcNAc transferase regulates collagen deposition and fibrosis resolution in idiopathic pulmonary fibrosis. Front Immunol 2024; 15:1387197. [PMID: 38665916 PMCID: PMC11043510 DOI: 10.3389/fimmu.2024.1387197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
Background Idiopathic pulmonary fibrosis (IPF) is a chronic pulmonary disease that is characterized by an excessive accumulation of extracellular matrix (ECM) proteins (e.g. collagens) in the parenchyma, which ultimately leads to respiratory failure and death. While current therapies exist to slow the progression, no therapies are available to resolve fibrosis. Methods We characterized the O-linked N-Acetylglucosamine (O-GlcNAc) transferase (OGT)/O-GlcNAc axis in IPF using single-cell RNA-sequencing (scRNA-seq) data and human lung sections and isolated fibroblasts from IPF and non-IPF donors. The underlying mechanism(s) of IPF were further investigated using multiple experimental models to modulate collagen expression and accumulation by genetically and pharmacologically targeting OGT. Furthermore, we hone in on the transforming growth factor-beta (TGF-β) effector molecule, Smad3, by co-expressing it with OGT to determine if it is modified and its subsequent effect on Smad3 activation. Results We found that OGT and O-GlcNAc levels are upregulated in patients with IPF compared to non-IPF. We report that the OGT regulates collagen deposition and fibrosis resolution, which is an evolutionarily conserved process demonstrated across multiple species. Co-expression of OGT and Smad3 showed that Smad3 is O-GlcNAc modified. Blocking OGT activity resulted in decreased phosphorylation at Ser-423/425 of Smad3 attenuating the effects of TGF-β1 induced collagen expression/deposition. Conclusion OGT inhibition or knockdown successfully blocked and reversed collagen expression and accumulation, respectively. Smad3 is discovered to be a substrate of OGT and its O-GlcNAc modification(s) directly affects its phosphorylation state. These data identify OGT as a potential target in pulmonary fibrosis resolution, as well as other diseases that might have aberrant ECM/collagen accumulation.
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Affiliation(s)
- Shia Vang
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Eric Scott Helton
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Yiming Guo
- Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Bailey Burpee
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Elex Rose
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Molly Easter
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Seth Bollenbecker
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Meghan June Hirsch
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Emma Lea Matthews
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Luke Isaac Jones
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Patrick Henry Howze
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Vasanthi Rajasekaran
- Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Rebecca Denson
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Phillip Cochran
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Isaac Kwame Attah
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Heather Olson
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Geremy Clair
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Girish Melkani
- Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Stefanie Krick
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jarrod Wesley Barnes
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
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3
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Liu X, Cai YD, Chiu JC. Regulation of protein O-GlcNAcylation by circadian, metabolic, and cellular signals. J Biol Chem 2024; 300:105616. [PMID: 38159854 PMCID: PMC10810748 DOI: 10.1016/j.jbc.2023.105616] [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: 07/24/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 01/03/2024] Open
Abstract
O-linked β-N-acetylglucosamine (O-GlcNAcylation) is a dynamic post-translational modification that regulates thousands of proteins and almost all cellular processes. Aberrant O-GlcNAcylation has been associated with numerous diseases, including cancer, neurodegenerative diseases, cardiovascular diseases, and type 2 diabetes. O-GlcNAcylation is highly nutrient-sensitive since it is dependent on UDP-GlcNAc, the end product of the hexosamine biosynthetic pathway (HBP). We previously observed daily rhythmicity of protein O-GlcNAcylation in a Drosophila model that is sensitive to the timing of food consumption. We showed that the circadian clock is pivotal in regulating daily O-GlcNAcylation rhythms given its control of the feeding-fasting cycle and hence nutrient availability. Interestingly, we reported that the circadian clock also modulates daily O-GlcNAcylation rhythm by regulating molecular mechanisms beyond the regulation of food consumption time. A large body of work now indicates that O-GlcNAcylation is likely a generalized cellular status effector as it responds to various cellular signals and conditions, such as ER stress, apoptosis, and infection. In this review, we summarize the metabolic regulation of protein O-GlcNAcylation through nutrient availability, HBP enzymes, and O-GlcNAc processing enzymes. We discuss the emerging roles of circadian clocks in regulating daily O-GlcNAcylation rhythm. Finally, we provide an overview of other cellular signals or conditions that impact O-GlcNAcylation. Many of these cellular pathways are themselves regulated by the clock and/or metabolism. Our review highlights the importance of maintaining optimal O-GlcNAc rhythm by restricting eating activity to the active period under physiological conditions and provides insights into potential therapeutic targets of O-GlcNAc homeostasis under pathological conditions.
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Affiliation(s)
- Xianhui Liu
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, California, USA
| | - Yao D Cai
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, California, USA
| | - Joanna C Chiu
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, California, USA.
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4
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Hu YJ, Zhang X, Lv HM, Liu Y, Li SZ. Protein O-GlcNAcylation: The sweet hub in liver metabolic flexibility from a (patho)physiological perspective. Liver Int 2024; 44:293-315. [PMID: 38110988 DOI: 10.1111/liv.15812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/18/2023] [Accepted: 11/22/2023] [Indexed: 12/20/2023]
Abstract
O-GlcNAcylation is a dynamic, reversible and atypical O-glycosylation that regulates various cellular physiological processes via conformation, stabilisation, localisation, chaperone interaction or activity of target proteins. The O-GlcNAcylation cycle is precisely controlled by collaboration between O-GlcNAc transferase and O-GlcNAcase. Uridine-diphosphate-N-acetylglucosamine, the sole donor of O-GlcNAcylation produced by the hexosamine biosynthesis pathway, is controlled by the input of glucose, glutamine, acetyl coenzyme A and uridine triphosphate, making it a sensor of the fluctuation of molecules, making O-GlcNAcylation a pivotal nutrient sensor for the metabolism of carbohydrates, amino acids, lipids and nucleotides. O-GlcNAcylation, particularly prevalent in liver, is the core hub for controlling systemic glucose homeostasis due to its nutritional sensitivity and precise spatiotemporal regulation of insulin signal transduction. The pathology of various liver diseases has highlighted hepatic metabolic disorder and dysfunction, and abnormal O-GlcNAcylation also plays a specific pathological role in these processes. Therefore, this review describes the unique features of O-GlcNAcylation and its dynamic homeostasis maintenance. Additionally, it explains the underlying nutritional sensitivity of O-GlcNAcylation and discusses its mechanism of spatiotemporal modulation of insulin signal transduction and liver metabolic homeostasis during the fasting and feeding cycle. This review emphasises the pathophysiological implications of O-GlcNAcylation in nonalcoholic fatty liver disease, nonalcoholic steatohepatitis and hepatic fibrosis, and focuses on the adverse effects of hyper O-GlcNAcylation on liver cancer progression and metabolic reprogramming.
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Affiliation(s)
- Ya-Jie Hu
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Xu Zhang
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Hong-Ming Lv
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Yang Liu
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shi-Ze Li
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
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5
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Du P, Zhang X, Lian X, Hölscher C, Xue G. O-GlcNAcylation and Its Roles in Neurodegenerative Diseases. J Alzheimers Dis 2024; 97:1051-1068. [PMID: 38250776 DOI: 10.3233/jad-230955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
As a non-classical post-translational modification, O-linked β-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation) is widely found in human organ systems, particularly in our brains, and is indispensable for healthy cell biology. With the increasing age of the global population, the incidence of neurodegenerative diseases is increasing, too. The common characteristic of these disorders is the aggregation of abnormal proteins in the brain. Current research has found that O-GlcNAcylation dysregulation is involved in misfolding or aggregation of these abnormal proteins to mediate disease progression, but the specific mechanism has not been defined. This paper reviews recent studies on O-GlcNAcylation's roles in several neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, Machado-Joseph's disease, and giant axonal neuropathy, and shows that O-GlcNAcylation, as glucose metabolism sensor, mediating synaptic function, participating in oxidative stress response and signaling pathway conduction, directly or indirectly regulates characteristic pathological protein toxicity and affects disease progression. The existing results suggest that targeting O-GlcNAcylation will provide new ideas for clinical diagnosis, prevention, and treatment of neurodegenerative diseases.
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Affiliation(s)
- Pengyang Du
- Department of Neurology, The Second Hospital of Shanxi Medical University, Taiyuan, China
| | - Xiaomin Zhang
- Department of Neurology, The Second Hospital of Shanxi Medical University, Taiyuan, China
| | - Xia Lian
- Department of Neurology, The Second Hospital of Shanxi Medical University, Taiyuan, China
| | - Christian Hölscher
- Academy of Chinese Medical Science, Henan University of Chinese Medicine, Zhengzhou, China
| | - Guofang Xue
- Department of Neurology, The Second Hospital of Shanxi Medical University, Taiyuan, China
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6
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Ye L, Ding W, Xiao D, Jia Y, Zhao Z, Ao X, Wang J. O-GlcNAcylation: cellular physiology and therapeutic target for human diseases. MedComm (Beijing) 2023; 4:e456. [PMID: 38116061 PMCID: PMC10728774 DOI: 10.1002/mco2.456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023] Open
Abstract
O-linked-β-N-acetylglucosamine (O-GlcNAcylation) is a distinctive posttranslational protein modification involving the coordinated action of O-GlcNAc transferase and O-GlcNAcase, primarily targeting serine or threonine residues in various proteins. This modification impacts protein functionality, influencing stability, protein-protein interactions, and localization. Its interaction with other modifications such as phosphorylation and ubiquitination is becoming increasingly evident. Dysregulation of O-GlcNAcylation is associated with numerous human diseases, including diabetes, nervous system degeneration, and cancers. This review extensively explores the regulatory mechanisms of O-GlcNAcylation, its effects on cellular physiology, and its role in the pathogenesis of diseases. It examines the implications of aberrant O-GlcNAcylation in diabetes and tumorigenesis, highlighting novel insights into its potential role in cardiovascular diseases. The review also discusses the interplay of O-GlcNAcylation with other protein modifications and its impact on cell growth and metabolism. By synthesizing current research, this review elucidates the multifaceted roles of O-GlcNAcylation, providing a comprehensive reference for future studies. It underscores the potential of targeting the O-GlcNAcylation cycle in developing novel therapeutic strategies for various pathologies.
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Affiliation(s)
- Lin Ye
- School of Basic MedicineQingdao UniversityQingdaoChina
| | - Wei Ding
- The Affiliated Hospital of Qingdao UniversityQingdao Medical CollegeQingdao UniversityQingdaoChina
| | - Dandan Xiao
- School of Basic MedicineQingdao UniversityQingdaoChina
| | - Yi Jia
- School of Basic MedicineQingdao UniversityQingdaoChina
| | - Zhonghao Zhao
- School of Basic MedicineQingdao UniversityQingdaoChina
| | - Xiang Ao
- School of Basic MedicineQingdao UniversityQingdaoChina
| | - Jianxun Wang
- School of Basic MedicineQingdao UniversityQingdaoChina
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Yang W, Tian E, Chernish A, McCluggage P, Dalal K, Lara A, Ten Hagen KG, Tabak LA. Quantitative mapping of the in vivo O-GalNAc glycoproteome in mouse tissues identifies GalNAc-T2 O-glycosites in metabolic disorder. Proc Natl Acad Sci U S A 2023; 120:e2303703120. [PMID: 37862385 PMCID: PMC10614836 DOI: 10.1073/pnas.2303703120] [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: 09/03/2023] [Indexed: 10/22/2023] Open
Abstract
The family of GalNAc-Ts (GalNAcpolypeptide:N-Acetylgalactosaminyl transferases) catalyzes the first committed step in the synthesis of O-glycans, which is an abundant and biologically important protein modification. Abnormalities in the activity of individual GalNAc-Ts can result in congenital disorders of O-glycosylation (CDG) and influence a broad array of biological functions. How site-specific O-glycans regulate biology is unclear. Compiling in vivo O-glycosites would be an invaluable step in determining the function of site-specific O-glycans. We integrated chemical and enzymatic conditions that cleave O-glycosites, a higher-energy dissociation product ions-triggered electron-transfer/higher-energy collision dissociation mass spectrometry (MS) workflow and software to study nine mouse tissues and whole blood. We identified 2,154 O-glycosites from 595 glycoproteins. The O-glycosites and glycoproteins displayed consensus motifs and shared functions as classified by Gene Ontology terms. Limited overlap of O-glycosites was observed with protein O-GlcNAcylation and phosphorylation sites. Quantitative glycoproteomics and proteomics revealed a tissue-specific regulation of O-glycosites that the differential expression of Galnt isoenzymes in tissues partly contributes to. We examined the Galnt2-null mouse model, which phenocopies congenital disorder of glycosylation involving GALNT2 and revealed a network of glycoproteins that lack GalNAc-T2-specific O-glycans. The known direct and indirect functions of these glycoproteins appear consistent with the complex metabolic phenotypes observed in the Galnt2-null animals. Through this study and interrogation of databases and the literature, we have compiled an atlas of experimentally identified mouse O-glycosites consisting of 2,925 O-glycosites from 758 glycoproteins.
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Affiliation(s)
- Weiming Yang
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - E. Tian
- Developmental Glycobiology Section, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Aliona Chernish
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Peggy McCluggage
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Kruti Dalal
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Alexander Lara
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Kelly G. Ten Hagen
- Developmental Glycobiology Section, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
| | - Lawrence A. Tabak
- Section on Biological Chemistry, National Institute of Dental and Craniofacial Research (NIDCR), NIH, Bethesda, MD20892
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8
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Kim DY, Park J, Han IO. Hexosamine biosynthetic pathway and O-GlcNAc cycling of glucose metabolism in brain function and disease. Am J Physiol Cell Physiol 2023; 325:C981-C998. [PMID: 37602414 DOI: 10.1152/ajpcell.00191.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/03/2023] [Accepted: 08/03/2023] [Indexed: 08/22/2023]
Abstract
Impaired brain glucose metabolism is considered a hallmark of brain dysfunction and neurodegeneration. Disruption of the hexosamine biosynthetic pathway (HBP) and subsequent O-linked N-acetylglucosamine (O-GlcNAc) cycling has been identified as an emerging link between altered glucose metabolism and defects in the brain. Myriads of cytosolic and nuclear proteins in the nervous system are modified at serine or threonine residues with a single N-acetylglucosamine (O-GlcNAc) molecule by O-GlcNAc transferase (OGT), which can be removed by β-N-acetylglucosaminidase (O-GlcNAcase, OGA). Homeostatic regulation of O-GlcNAc cycling is important for the maintenance of normal brain activity. Although significant evidence linking dysregulated HBP metabolism and aberrant O-GlcNAc cycling to induction or progression of neuronal diseases has been obtained, the issue of whether altered O-GlcNAcylation is causal in brain pathogenesis remains uncertain. Elucidation of the specific functions and regulatory mechanisms of individual O-GlcNAcylated neuronal proteins in both normal and diseased states may facilitate the identification of novel therapeutic targets for various neuronal disorders. The information presented in this review highlights the importance of HBP/O-GlcNAcylation in the neuronal system and summarizes the roles and potential mechanisms of O-GlcNAcylated neuronal proteins in maintaining normal brain function and initiation and progression of neurological diseases.
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Affiliation(s)
- Dong Yeol Kim
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
| | - Jiwon Park
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
| | - Inn-Oc Han
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
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Xu S, Suttapitugsakul S, Tong M, Wu R. Systematic analysis of the impact of phosphorylation and O-GlcNAcylation on protein subcellular localization. Cell Rep 2023; 42:112796. [PMID: 37453062 PMCID: PMC10530397 DOI: 10.1016/j.celrep.2023.112796] [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: 05/23/2022] [Revised: 05/02/2023] [Accepted: 06/27/2023] [Indexed: 07/18/2023] Open
Abstract
The subcellular localization of proteins is critical for their functions in eukaryotic cells and is tightly correlated with protein modifications. Here, we comprehensively investigate the nuclear-cytoplasmic distributions of the phosphorylated, O-GlcNAcylated, and non-modified forms of proteins to dissect the correlation between protein distribution and modifications. Phosphorylated and O-GlcNAcylated proteins have overall higher nuclear distributions than non-modified ones. Different distributions among the phosphorylated, O-GlcNAcylated, and non-modified forms of proteins are associated with protein size, structure, and function, as well as local environment and adjacent residues around modification sites. Moreover, we perform site-mutagenesis experiments using phosphomimetic and phospho-null mutants of two proteins to validate the proteomic results. Additionally, the effects of the OGT/OGA inhibition on glycoprotein distribution are systematically investigated, and the distribution changes of glycoproteins are related to their abundance changes under the inhibitions. Systematic investigation of the relationship between protein modification and localization advances our understanding of protein functions.
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Affiliation(s)
- Senhan Xu
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Suttipong Suttapitugsakul
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Ming Tong
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Ronghu Wu
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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Shin H, Leung A, Costello KR, Senapati P, Kato H, Moore RE, Lee M, Lin D, Tang X, Pirrotte P, Bouman Chen Z, Schones DE. Inhibition of DNMT1 methyltransferase activity via glucose-regulated O-GlcNAcylation alters the epigenome. eLife 2023; 12:e85595. [PMID: 37470704 PMCID: PMC10390045 DOI: 10.7554/elife.85595] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 07/19/2023] [Indexed: 07/21/2023] Open
Abstract
The DNA methyltransferase activity of DNMT1 is vital for genomic maintenance of DNA methylation. We report here that DNMT1 function is regulated by O-GlcNAcylation, a protein modification that is sensitive to glucose levels, and that elevated O-GlcNAcylation of DNMT1 from high glucose environment leads to alterations to the epigenome. Using mass spectrometry and complementary alanine mutation experiments, we identified S878 as the major residue that is O-GlcNAcylated on human DNMT1. Functional studies in human and mouse cells further revealed that O-GlcNAcylation of DNMT1-S878 results in an inhibition of methyltransferase activity, resulting in a general loss of DNA methylation that preferentially occurs at partially methylated domains (PMDs). This loss of methylation corresponds with an increase in DNA damage and apoptosis. These results establish O-GlcNAcylation of DNMT1 as a mechanism through which the epigenome is regulated by glucose metabolism and implicates a role for glycosylation of DNMT1 in metabolic diseases characterized by hyperglycemia.
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Affiliation(s)
- Heon Shin
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Amy Leung
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Kevin R Costello
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
- Irell and Manella Graduate School of Biological Sciences, City of HopeDuarteUnited States
| | - Parijat Senapati
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Hiroyuki Kato
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Roger E Moore
- Integrated Mass Spectrometry Shared Resource, City of Hope Comprehensive Cancer Center DuarteDuarteUnited States
| | - Michael Lee
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
- Irell and Manella Graduate School of Biological Sciences, City of HopeDuarteUnited States
| | - Dimitri Lin
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Xiaofang Tang
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
| | - Patrick Pirrotte
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
- Integrated Mass Spectrometry Shared Resource, City of Hope Comprehensive Cancer Center DuarteDuarteUnited States
- Cancer & Cell Biology Division, Translational Genomics Research InstitutePhoenixUnited States
| | - Zhen Bouman Chen
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
- Irell and Manella Graduate School of Biological Sciences, City of HopeDuarteUnited States
| | - Dustin E Schones
- Department of Diabetes Complications and Metabolism, Beckman Research Institute, City of HopeDuarteUnited States
- Irell and Manella Graduate School of Biological Sciences, City of HopeDuarteUnited States
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11
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Demir R, Deveci R. In silico analysis of the possible crosstalk between O-linked β-GlcNAcylation and phosphorylation sites of Disabled 1 adaptor protein in vertebrates. Amino Acids 2023:10.1007/s00726-023-03266-5. [PMID: 37067567 DOI: 10.1007/s00726-023-03266-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 04/10/2023] [Indexed: 04/18/2023]
Abstract
Disabled 1 (Dab1) is an adaptor protein with essential functions regulated by reelin signaling and affects many biological processes in the nervous system, including cell motility, adhesion, cortical development, maturation, and synaptic plasticity. Posttranslational modifications directly guide the fates of cytoplasmic proteins to complete their functions correctly. Reciprocal crosstalk between O-GlcNAcylation and phosphorylation is a dynamic modification in cytoplasmic proteins. It modulates the functions of the proteins by regulating their interactions with other molecules in response to the continuously changeable cell microenvironment. Although Dab1 contains conserved recognition sites for phosphorylation in their N-terminal protein interaction domain, the O-β-GlcNAcylation and phosphorylation sites of human Dab1 sequence, their reciprocal crosstalk, and potential kinases catalyzing the phosphorylation remain unknown. In this study, we determined potential thirty-seven O-β-GlcNAcylation and sixty-seven phosphorylation sites. Conserved twenty-one residues of these glycosylated sites were also phosphorylated with various kinases, including ATM, CKI, DNAPK, GSK3, PKC, PKG, RSK, cdc2, cdk5, and p38MAPK. In addition, we analyzed these conserved sites at our constructed two- and three-dimensional structures of human Dab1 protein. Dab1 protein models were frequently composed of coil structures as well as α-helix and β-strands. Many of these conserved crosstalk sites between O-β-GlcNAcylation and phosphorylation were localized at the coil region of the protein model. These findings may guide biochemical, genetic, and glyco-biology based on further experiments about the Dab1 signaling process. Understanding these modifications might change the point of view of the Dab1 signaling process and treatment for pathological conditions in neurodegenerative diseases such as Alzheimer's disease.
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Affiliation(s)
- Ramiz Demir
- Molecular Biology Section, Department of Biology, Faculty of Science, Ege University, Bornova, 35040,, Izmir, Turkey
- Graduate School of Health Science, Koç University Research Center for Translational Medicine (KUTTAM), Koç University, 34010, Istanbul, Turkey
| | - Remziye Deveci
- Molecular Biology Section, Department of Biology, Faculty of Science, Ege University, Bornova, 35040,, Izmir, Turkey.
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12
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Sitosari H, Morimoto I, Weng Y, Zheng Y, Fukuhara Y, Ikegame M, Okamura H. Inhibition of protein phosphatase 2A by okadaic acid induces translocation of nucleocytoplasmic O-GlcNAc transferase. Biochem Biophys Res Commun 2023; 646:50-55. [PMID: 36706705 DOI: 10.1016/j.bbrc.2023.01.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 01/15/2023]
Abstract
Post-translational modification (PTM) is crucial for many biological events, such as the modulation of bone metabolism. Phosphorylation and O-GlcNAcylation are two examples of PTMs that can occur at the same site in the protein: serine and threonine residues. This phenomenon may cause crosstalk and possible interactions between the molecules involved. Protein phosphatase 2 A (PP2A) is widely expressed throughout the body and plays a major role in dephosphorylation. At the same location where PP2A acts, O-GlcNAc transferase (OGT) can introduce uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) molecules and mediates O-GlcNAc modifications. To examine the effects of PP2A inhibition on OGT localization and expression, osteoblastic MC3T3-E1 cells were treated with Okadaic Acid (OA), a potent PP2A inhibitor. In the control cells, OGT was strictly localized in the nucleus. However, OGT was observed diffusely in the cytoplasm of the OA-treated cells. This change in localization from the nucleus to the cytoplasm resulted from an increase in mitochondrial OGT expression and translocation of the nucleocytoplasmic isoform. Furthermore, knockdown of PP2A catalytic subunit α isoform (PP2A Cα) significantly affected OGT expression (p < 0.05), and there was a correlation between PP2A Cα and OGT expression (r = 0.93). These results suggested a possible interaction between PP2A and OGT, which strengthens the notion of an interaction between phosphorylation and O-GlcNAcylation.
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Affiliation(s)
- Heriati Sitosari
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan; Department of Oral Biology, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia
| | - Ikkei Morimoto
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan
| | - Yao Weng
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan; Department of Oral Rehabilitation and Implantology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan
| | - Yilin Zheng
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan
| | - Yoko Fukuhara
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan
| | - Mika Ikegame
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan
| | - Hirohiko Okamura
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 770-8525, Japan.
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13
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Lu Q, Zhang X, Liang T, Bai X. O-GlcNAcylation: an important post-translational modification and a potential therapeutic target for cancer therapy. Mol Med 2022; 28:115. [PMID: 36104770 PMCID: PMC9476278 DOI: 10.1186/s10020-022-00544-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 09/07/2022] [Indexed: 02/07/2023] Open
Abstract
O-linked β-d-N-acetylglucosamine (O-GlcNAc) is an important post-translational modification of serine or threonine residues on thousands of proteins in the nucleus and cytoplasm of all animals and plants. In eukaryotes, only two conserved enzymes are involved in this process. O-GlcNAc transferase is responsible for adding O-GlcNAc to proteins, while O-GlcNAcase is responsible for removing it. Aberrant O-GlcNAcylation is associated with a variety of human diseases, such as diabetes, cancer, neurodegenerative diseases, and cardiovascular diseases. Numerous studies have confirmed that O-GlcNAcylation is involved in the occurrence and progression of cancers in multiple systems throughout the body. It is also involved in regulating multiple cancer hallmarks, such as metabolic reprogramming, proliferation, invasion, metastasis, and angiogenesis. In this review, we first describe the process of O-GlcNAcylation and the structure and function of O-GlcNAc cycling enzymes. In addition, we detail the occurrence of O-GlcNAc in various cancers and the role it plays. Finally, we discuss the potential of O-GlcNAc as a promising biomarker and novel therapeutic target for cancer diagnosis, treatment, and prognosis.
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14
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Liu X, Chiu JC. Nutrient-sensitive protein O-GlcNAcylation shapes daily biological rhythms. Open Biol 2022; 12:220215. [PMID: 36099933 PMCID: PMC9470261 DOI: 10.1098/rsob.220215] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 08/17/2022] [Indexed: 11/12/2022] Open
Abstract
O-linked-N-acetylglucosaminylation (O-GlcNAcylation) is a nutrient-sensitive protein modification that alters the structure and function of a wide range of proteins involved in diverse cellular processes. Similar to phosphorylation, another protein modification that targets serine and threonine residues, O-GlcNAcylation occupancy on cellular proteins exhibits daily rhythmicity and has been shown to play critical roles in regulating daily rhythms in biology by modifying circadian clock proteins and downstream effectors. We recently reported that daily rhythm in global O-GlcNAcylation observed in Drosophila tissues is regulated via the integration of circadian and metabolic signals. Significantly, mistimed feeding, which disrupts coordination of these signals, is sufficient to dampen daily O-GlcNAcylation rhythm and is predicted to negatively impact animal biological rhythms and health span. In this review, we provide an overview of published and potential mechanisms by which metabolic and circadian signals regulate hexosamine biosynthetic pathway metabolites and enzymes, as well as O-GlcNAc processing enzymes to shape daily O-GlcNAcylation rhythms. We also discuss the significance of functional interactions between O-GlcNAcylation and other post-translational modifications in regulating biological rhythms. Finally, we highlight organ/tissue-specific cellular processes and molecular pathways that could be modulated by rhythmic O-GlcNAcylation to regulate time-of-day-specific biology.
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Affiliation(s)
- Xianhui Liu
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California Davis, Davis, CA, USA
- Department of Pharmacology, School of Medicine, University of California Davis, Davis, CA, USA
| | - Joanna C. Chiu
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California Davis, Davis, CA, USA
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15
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Chi Z, Wu X, Zhang Q, Zhai F, Xu Z, Zhang D, Chen Q. Titanium-based metal-organic framework MIL-125(Ti) for the highly selective isolation and purification of immunoglobulin G from human serum. J Sep Sci 2022; 45:3754-3762. [PMID: 35933591 DOI: 10.1002/jssc.202200357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 11/10/2022]
Abstract
Titanium-based metal-organic framework MIL-125(Ti) was synthesized by the hydrothermal method of terephthalic acid and tetra butyl titanate in N-N dimethylformamide and methanol. MIL-125(Ti) was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, nitrogen adsorption-desorption, energy-dispersive X-ray spectroscopy, zeta potential, scanning electron microscope and transmission electron microscopy. The results showed MIL-125(Ti) could be used as a potential adsorbent for protein separation and purification due to the high specific surface area, high stability and strong hydrophobicity. As a result, MIL-125(Ti) had adsorption selectivity for immunoglobulin G, which was due to hydrogen bond between MIL-125(Ti) and protein. At pH 8.0, the maximum adsorption efficiency of 0.25 mg MIL-125(Ti) for 300 μL 100 μg mL-1 immunoglobulin G was 98.3%, and its maximum adsorption capacity was 232.56 mg g-1 . The elution efficiency of immunoglobulin G was 92.4% by 0.1% SDS. SDS-PAGE result demonstrated the successful isolation of highly purified immunoglobulin G from the human serum. Therefore, a new method of separation and purification of immunoglobulin G in human serum using titanium-based metal-organic framework MIL-125(Ti) as a solid-phase adsorbent was established, which broadened the application scope of metal-organic frameworks. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Zixin Chi
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
| | - Xi Wu
- Liaoning University, Shenyang, 110036, People's Republic of China
| | - Qiqi Zhang
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
| | - Fengyang Zhai
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
| | - Zesheng Xu
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
| | - Dandan Zhang
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
| | - Qing Chen
- Shenyang Medical College, Shenyang, 110034, People's Republic of China
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16
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O-GlcNAcylation: An Emerging Protein Modification Regulating the Hippo Pathway. Cancers (Basel) 2022; 14:cancers14123013. [PMID: 35740678 PMCID: PMC9221189 DOI: 10.3390/cancers14123013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The contact point between the Hippo pathway, which serves as a central hub for various external environments, and O-GlcNAcylation, which is a non-canonical glycosylation process acting as a dynamic regulator in various signal transduction pathways, has recently been identified. This review aims to summarize the function of O-GlcNAcylation as an intrinsic and extrinsic regulator of the Hippo pathway. Abstract The balance between cellular proliferation and apoptosis and the regulation of cell differentiation must be established to maintain tissue homeostasis. These cellular responses involve the kinase cascade-mediated Hippo pathway as a crucial regulator. Hence, Hippo pathway dysregulation is implicated in diverse diseases, including cancer. O-GlcNAcylation is a non-canonical glycosylation that affects multiple signaling pathways through its interplay with phosphorylation in the nucleus and cytoplasm. An abnormal increase in the O-GlcNAcylation levels in various cancer cells is a potent factor in Hippo pathway dysregulation. Intriguingly, Hippo pathway dysregulation also disrupts O-GlcNAc homeostasis, leading to a persistent elevation of O-GlcNAcylation levels, which is potentially pathogenic in several diseases. Therefore, O-GlcNAcylation is gaining attention as a protein modification that regulates the Hippo pathway. This review presents a framework on how O-GlcNAcylation regulates the Hippo pathway and forms a self-perpetuating cycle with it. The pathological significance of this self-perpetuating cycle and clinical strategies for targeting O-GlcNAcylation that causes Hippo pathway dysregulation are also discussed.
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17
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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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18
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He J, Fan Z, Tian Y, Yang W, Zhou Y, Zhu Q, Zhang W, Qin W, Yi W. Spatiotemporal Activation of Protein O-GlcNAcylation in Living Cells. J Am Chem Soc 2022; 144:4289-4293. [PMID: 35138101 DOI: 10.1021/jacs.1c11041] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
O-linked N-acetylglucosamine (O-GlcNAc) is a prevalent protein modification that plays fundamental roles in both cell physiology and pathology. O-GlcNAc is catalyzed solely by O-GlcNAc transferase (OGT). The study of protein O-GlcNAc function is limited by the lack of tools to control OGT activity with spatiotemporal resolution in cells. Here, we report light control of OGT activity in cells by replacing a catalytically essential lysine residue with a genetically encoded photocaged lysine. This enables the expression of a transiently inactivated form of OGT, which can be rapidly reactivated by photo-decaging. We demonstrate the activation of OGT activity by monitoring the time-dependent increase of cellular O-GlcNAc and profile glycoproteins using mass-spectrometry-based quantitative proteomics. We further apply this activation strategy to control the morphological contraction of fibroblasts. Furthermore, we achieved spatial activation of OGT activity predominantly in the cytosol. Thus, our approach provides a valuable chemical tool to control cellular O-GlcNAc with much needed spatiotemporal precision, which aids in a better understanding of O-GlcNAc function.
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Affiliation(s)
- Jiahui He
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhiya Fan
- National Center for Protein Sciences Beijing, State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Yinping Tian
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China.,Carbohydrate-Based Drug Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Weiwei Yang
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yichao Zhou
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qiang Zhu
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wanjun Zhang
- National Center for Protein Sciences Beijing, State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Weijie Qin
- National Center for Protein Sciences Beijing, State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Wen Yi
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
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19
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Mannino MP, Hart GW. The Beginner’s Guide to O-GlcNAc: From Nutrient Sensitive Pathway Regulation to Its Impact on the Immune System. Front Immunol 2022; 13:828648. [PMID: 35173739 PMCID: PMC8841346 DOI: 10.3389/fimmu.2022.828648] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 01/05/2022] [Indexed: 12/27/2022] Open
Abstract
The addition of N-acetyl glucosamine (GlcNAc) on the hydroxy group of serine/threonine residues is known as O-GlcNAcylation (OGN). The dynamic cycling of this monosaccharide on and off substrates occurs via O-linked β-N-acetylglucosamine transferase (OGT) and O-linked β-N-acetylglucosaminase (OGA) respectively. These enzymes are found ubiquitously in eukaryotes and genetic knock outs of the ogt gene has been found to be lethal in embryonic mice. The substrate scope of these enzymes is vast, over 15,000 proteins across 43 species have been identified with O-GlcNAc. OGN has been known to play a key role in several cellular processes such as: transcription, translation, cell signaling, nutrient sensing, immune cell development and various steps of the cell cycle. However, its dysregulation is present in various diseases: cancer, neurodegenerative diseases, diabetes. O-GlcNAc is heavily involved in cross talk with other post-translational modifications (PTM), such as phosphorylation, acetylation, and ubiquitination, by regulating each other’s cycling enzymes or directly competing addition on the same substrate. This crosstalk between PTMs can affect gene expression, protein localization, and protein stability; therefore, regulating a multitude of cell signaling pathways. In this review the roles of OGN will be discussed. The effect O-GlcNAc exerts over protein-protein interactions, the various forms of crosstalk with other PTMs, and its role as a nutrient sensor will be highlighted. A summary of how these O-GlcNAc driven processes effect the immune system will also be included.
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20
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Comparative O-GlcNAc Proteomic Analysis Reveals a Role of O-GlcNAcylated SAM68 in Lung Cancer Aggressiveness. Cancers (Basel) 2022; 14:cancers14010243. [PMID: 35008409 PMCID: PMC8749979 DOI: 10.3390/cancers14010243] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/19/2021] [Accepted: 12/30/2021] [Indexed: 01/25/2023] Open
Abstract
Simple Summary Lung cancer claims the most lives annually among cancers; to date, invasion and metastasis still pose challenges to effective treatment. O-GlcNAcylation, an enzymatic modification of proteins after biosynthesis, modulates the functions of many proteins. Aberrant O-GlcNAcylation is linked to pathogenic mechanisms of cancer, including invasion and metastasis. However, little is known about the profile of O-GlcNAcylated proteins involved in cancer aggressiveness. Here, by comparing profiles of O-GlcNAcylated proteins from two lung cancer cell lines different in their invasive potential, we identified candidates for O-GlcNAcylated proteins that may be involved in cancer aggressiveness. One of these candidates, SAM68, was further characterized. Results confirmed O-GlcNAcylation of SAM68; functional analyses on SAM68 with mutations at O-GlcNAcylation sites suggested a role of O-GlcNAcylated SAM68 in modulating lung cancer cell migration/invasion. Future elucidation of the functional significance of differential O-GlcNAcylation of proteins identified in this study may provide new insights into mechanisms of lung cancer progression. Abstract O-GlcNAcylation is a reversible and dynamic post-translational protein modification catalyzed by O-GlcNAc transferase (OGT). Despite the reported association of O-GlcNAcylation with cancer metastasis, the O-GlcNAc proteome profile for cancer aggressiveness remains largely uncharacterized. Here, we report our comparative O-GlcNAc proteome profiling of two differentially invasive lung adenocarcinoma cell lines, which identified 158 down-regulated and 106 up-regulated candidates in highly invasive cells. Among these differential proteins, a nuclear RNA-binding protein, SAM68 (SRC associated in mitosis of 68 kDa), was further investigated. Results showed that SAM68 is O-GlcNAcylated and may interact with OGT in the nucleus. Eleven O-GlcNAcylation sites were identified, and data from mutant analysis suggested that multiple serine residues in the N-terminal region are important for O-GlcNAcylation and the function of SAM68 in modulating cancer cell migration and invasion. Analysis of clinical specimens found that high SAM68 expression was associated with late cancer stages, and patients with high-OGT/high-SAM68 expression in their tumors had poorer overall survival compared to those with low-OGT/low-SAM68 expression. Our study revealed an invasiveness-associated O-GlcNAc proteome profile and connected O-GlcNAcylated SAM68 to lung cancer aggressiveness.
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21
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Sun L, Lv S, Song T. O-GlcNAcylation links oncogenic signals and cancer epigenetics. Discov Oncol 2021; 12:54. [PMID: 35201498 PMCID: PMC8777512 DOI: 10.1007/s12672-021-00450-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/11/2021] [Indexed: 12/19/2022] Open
Abstract
Prevalent dysregulation of epigenetic modifications plays a pivotal role in cancer. Targeting epigenetic abnormality is a new strategy for cancer therapy. Understanding how conventional oncogenic factors cause epigenetic abnormality is of great basic and translational value. O-GlcNAcylation is a protein modification which affects physiology and pathophysiology. In mammals, O-GlcNAcylation is catalyzed by one single enzyme OGT and removed by one single enzyme OGA. O-GlcNAcylation is affected by the availability of the donor, UDP-GlcNAc, generated by the serial enzymatic reactions in the hexoamine biogenesis pathway (HBP). O-GlcNAcylation regulates a wide spectrum of substrates including many proteins involved in epigenetic modification. Like epigenetic modifications, abnormality of O-GlcNAcylation is also common in cancer. Studies have revealed substantial impact on HBP enzymes and OGT/OGA by oncogenic signals. In this review, we will first summarize how oncogenic signals regulate HBP enzymes, OGT and OGA in cancer. We will then integrate this knowledge with the up to date understanding how O-GlcNAcylation regulates epigenetic machinery. With this, we propose a signal axis from oncogenic signals through O-GlcNAcylation dysregulation to epigenetic abnormality in cancer. Further elucidation of this axis will not only advance our understanding of cancer biology but also provide new revenues towards cancer therapy.
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Affiliation(s)
- Lidong Sun
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China.
| | - Suli Lv
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Tanjing Song
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China.
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22
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Seo E, Kim M, Park S, Park S, Oh D, Bornscheuer U, Park J. Enzyme Access Tunnel Engineering in Baeyer‐Villiger Monooxygenases to Improve Oxidative Stability and Biocatalyst Performance. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202101044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Eun‐Ji Seo
- Department of Food Science and Engineering Ewha Womans University Seoul 03760 Republic of Korea
| | - Myeong‐Ju Kim
- Department of Food Science and Engineering Ewha Womans University Seoul 03760 Republic of Korea
| | - So‐Yeon Park
- Department of Food Science and Engineering Ewha Womans University Seoul 03760 Republic of Korea
| | - Seongsoon Park
- Department of Chemistry, Center for NanoBio Applied Technology Sungshin Women's University Seoul 01133 Republic of Korea
| | - Deok‐Kun Oh
- Department of Bioscience and Biotechnology Konkuk University Seoul 05029 Republic of Korea
| | - Uwe Bornscheuer
- Institute of Biochemistry, Department of Biotechnology & Enzyme Catalysis Greifswald University Greifswald 17487 Germany
| | - Jin‐Byung Park
- Department of Food Science and Engineering Ewha Womans University Seoul 03760 Republic of Korea
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23
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Ma J, Hou C, Li Y, Chen S, Wu C. OGT Protein Interaction Network (OGT-PIN): A Curated Database of Experimentally Identified Interaction Proteins of OGT. Int J Mol Sci 2021; 22:ijms22179620. [PMID: 34502531 PMCID: PMC8431785 DOI: 10.3390/ijms22179620] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 01/01/2023] Open
Abstract
Interactions between proteins are essential to any cellular process and constitute the basis for molecular networks that determine the functional state of a cell. With the technical advances in recent years, an astonishingly high number of protein–protein interactions has been revealed. However, the interactome of O-linked N-acetylglucosamine transferase (OGT), the sole enzyme adding the O-linked β-N-acetylglucosamine (O-GlcNAc) onto its target proteins, has been largely undefined. To that end, we collated OGT interaction proteins experimentally identified in the past several decades. Rigorous curation of datasets from public repositories and O-GlcNAc-focused publications led to the identification of up to 929 high-stringency OGT interactors from multiple species studied (including Homo sapiens, Mus musculus, Rattus norvegicus, Drosophila melanogaster, Arabidopsis thaliana, and others). Among them, 784 human proteins were found to be interactors of human OGT. Moreover, these proteins spanned a very diverse range of functional classes (e.g., DNA repair, RNA metabolism, translational regulation, and cell cycle), with significant enrichment in regulating transcription and (co)translation. Our dataset demonstrates that OGT is likely a hub protein in cells. A webserver OGT-Protein Interaction Network (OGT-PIN) has also been created, which is freely accessible.
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Affiliation(s)
- Junfeng Ma
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University Medical Center, Washington, DC 20057, USA; (Y.L.); (C.W.)
- Correspondence: ; Tel.: +1-202-6873802
| | - Chunyan Hou
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;
| | - Yaoxiang Li
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University Medical Center, Washington, DC 20057, USA; (Y.L.); (C.W.)
| | - Shufu Chen
- School of Engineering, Pennsylvania State University Behrend, Erie, PA 16563, USA;
| | - Ci Wu
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University Medical Center, Washington, DC 20057, USA; (Y.L.); (C.W.)
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Liu X, Blaženović I, Contreras AJ, Pham TM, Tabuloc CA, Li YH, Ji J, Fiehn O, Chiu JC. Hexosamine biosynthetic pathway and O-GlcNAc-processing enzymes regulate daily rhythms in protein O-GlcNAcylation. Nat Commun 2021; 12:4173. [PMID: 34234137 PMCID: PMC8263742 DOI: 10.1038/s41467-021-24301-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 06/08/2021] [Indexed: 02/06/2023] Open
Abstract
The integration of circadian and metabolic signals is essential for maintaining robust circadian rhythms and ensuring efficient metabolism and energy use. Using Drosophila as an animal model, we show that cellular protein O-GlcNAcylation exhibits robust 24-hour rhythm and represents a key post-translational mechanism that regulates circadian physiology. We observe strong correlation between protein O-GlcNAcylation rhythms and clock-controlled feeding-fasting cycles, suggesting that O-GlcNAcylation rhythms are primarily driven by nutrient input. Interestingly, daily O-GlcNAcylation rhythms are severely dampened when we subject flies to time-restricted feeding at unnatural feeding time. This suggests the presence of clock-regulated buffering mechanisms that prevent excessive O-GlcNAcylation at non-optimal times of the day-night cycle. We show that this buffering mechanism is mediated by the expression and activity of GFAT, OGT, and OGA, which are regulated through integration of circadian and metabolic signals. Finally, we generate a mathematical model to describe the key factors that regulate daily O-GlcNAcylation rhythm.
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Affiliation(s)
- Xianhui Liu
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
| | - Ivana Blaženović
- grid.27860.3b0000 0004 1936 9684West Coast Metabolomics Center, University of California, Davis, CA USA
| | - Adam J. Contreras
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
| | - Thu M. Pham
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
| | - Christine A. Tabuloc
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
| | - Ying H. Li
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
| | - Jian Ji
- grid.509509.00000 0004 7699 6596School of Food Science, State Key Laboratory of Food Science and Technology, National Engineering Research Center for Functional Foods, School of Food Science Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi, Jiangsu China
| | - Oliver Fiehn
- grid.27860.3b0000 0004 1936 9684West Coast Metabolomics Center, University of California, Davis, CA USA
| | - Joanna C. Chiu
- grid.27860.3b0000 0004 1936 9684Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, CA USA
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25
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Mitochondrial O-GlcNAc Transferase Interacts with and Modifies Many Proteins and Its Up-Regulation Affects Mitochondrial Function and Cellular Energy Homeostasis. Cancers (Basel) 2021; 13:cancers13122956. [PMID: 34204801 PMCID: PMC8231590 DOI: 10.3390/cancers13122956] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 05/31/2021] [Accepted: 06/08/2021] [Indexed: 02/06/2023] Open
Abstract
O-GlcNAcylation is a cell glucose sensor. The addition of O-GlcNAc moieties to target protein is catalyzed by the O-Linked N-acetylglucosamine transferase (OGT). OGT is encoded by a single gene that yields differentially spliced OGT isoforms. One of them is targeted to mitochondria (mOGT). Although the impact of O-GlcNAcylation on cancer cells biology is well documented, mOGT's role remains poorly investigated. We performed studies using breast cancer cells with up-regulated mOGT or its catalytic inactive mutant to identify proteins specifically modified by mOGT. Proteomic approaches included isolation of mOGT protein partners and O-GlcNAcylated proteins from mitochondria-enriched fraction followed by their analysis by mass spectrometry. Moreover, we analyzed the impact of mOGT dysregulation on mitochondrial activity and cellular metabolism using a variety of biochemical assays. We found that mitochondrial OGT expression is glucose-dependent. Elevated mOGT expression affected the mitochondrial transmembrane potential and increased intramitochondrial ROS generation. Moreover, mOGT up-regulation caused a decrease in cellular ATP level. We identified many mitochondrial proteins as mOGT substrates. Most of these proteins are localized in the mitochondrial matrix and the inner mitochondrial membrane and participate in mitochondrial respiration, fatty acid metabolism, transport, translation, apoptosis, and mtDNA processes. Our findings suggest that mOGT interacts with and modifies many mitochondrial proteins, and its dysregulation affects cellular bioenergetics and mitochondria function.
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26
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Urso SJ, Lamitina T. The C. elegans Hypertonic Stress Response: Big Insights from Shrinking Worms. Cell Physiol Biochem 2021; 55:89-105. [PMID: 33626269 DOI: 10.33594/000000332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2021] [Indexed: 12/23/2022] Open
Abstract
Cell volume is one of the most aggressively defended physiological set points in biology. Changes in intracellular ion and water concentrations, which are induced by changes in metabolism or environmental exposures, disrupt protein folding, enzymatic activity, and macromolecular assemblies. To counter these challenges, cells and organisms have evolved multifaceted, evolutionarily conserved molecular mechanisms to restore cell volume and repair stress induced damage. However, many unanswered questions remain regarding the nature of cell volume 'sensing' as well as the molecular signaling pathways involved in activating physiological response mechanisms. Unbiased genetic screening in the model organism C. elegans is providing new and unexpected insights into these questions, particularly questions relating to the hypertonic stress response (HTSR) pathway. One surprising characteristic of the HTSR pathway in C. elegans is that it is under strong negative regulation by proteins involved in protein homeostasis and the extracellular matrix (ECM). The role of the ECM in particular highlights the importance of studying the HTSR in the context of a live organism where native ECM-tissue associations are preserved. A second novel and recently discovered characteristic is that the HTSR is regulated at the post-transcriptional level. The goal of this review is to describe these discoveries, to provide context for their implications, and to raise outstanding questions to guide future research.
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Affiliation(s)
- Sarel J Urso
- University of Pittsburgh, Graduate Program in Cell Biology and Physiology, Pittsburgh, PA, USA.,University of Pittsburgh, Departments of Pediatrics and Cell Biology, Pittsburgh, PA, USA
| | - Todd Lamitina
- University of Pittsburgh, Graduate Program in Cell Biology and Physiology, Pittsburgh, PA, USA, .,University of Pittsburgh, Departments of Pediatrics and Cell Biology, Pittsburgh, PA, USA
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27
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Stephen HM, Adams TM, Wells L. Regulating the Regulators: Mechanisms of Substrate Selection of the O-GlcNAc Cycling Enzymes OGT and OGA. Glycobiology 2021; 31:724-733. [PMID: 33498085 DOI: 10.1093/glycob/cwab005] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/07/2021] [Accepted: 01/08/2021] [Indexed: 12/20/2022] Open
Abstract
Thousands of nuclear and cytosolic proteins are modified with a single β-N-acetylglucosamine on serine and threonine residues in mammals, a modification termed O-GlcNAc. This modification is essential for normal development and plays important roles in virtually all intracellular processes. Additionally, O-GlcNAc is involved in many disease states, including cancer, diabetes, and X-linked intellectual disability. Given the myriad of functions of the O-GlcNAc modification, it is therefore somewhat surprising that O-GlcNAc cycling is mediated by only two enzymes: the O-GlcNAc transferase (OGT), which adds O-GlcNAc, and the O-GlcNAcase (OGA), which removes it. A significant outstanding question in the O-GlcNAc field is how do only two enzymes mediate such an abundant and dynamic modification. In this review, we explore the current understanding of mechanisms for substrate selection for the O-GlcNAc cycling enzymes. These mechanisms include direct substrate interaction with specific domains of OGT or OGA, selection of interactors via partner proteins, posttranslational modification of OGT or OGA, nutrient sensing, and localization alteration. Altogether, current research paints a picture of an exquisitely regulated and complex system by which OGT and OGA select substrates. We also make recommendations for future work, toward the goal of identifying interaction mechanisms for specific substrates that may be able to be exploited for various research and medical treatment goals.
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Affiliation(s)
- Hannah M Stephen
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens 30602, GA, USA
| | - Trevor M Adams
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens 30602, GA, USA
| | - Lance Wells
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens 30602, GA, USA
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28
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Ma J, Wu C, Hart GW. Analytical and Biochemical Perspectives of Protein O-GlcNAcylation. Chem Rev 2021; 121:1513-1581. [DOI: 10.1021/acs.chemrev.0c00884] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Junfeng Ma
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington D.C. 20057, United States
| | - Ci Wu
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington D.C. 20057, United States
| | - Gerald W. Hart
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, United States
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29
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Zuliani I, Lanzillotta C, Tramutola A, Francioso A, Pagnotta S, Barone E, Perluigi M, Di Domenico F. The Dysregulation of OGT/OGA Cycle Mediates Tau and APP Neuropathology in Down Syndrome. Neurotherapeutics 2021; 18:340-363. [PMID: 33258073 PMCID: PMC8116370 DOI: 10.1007/s13311-020-00978-4] [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] [Subscribe] [Scholar Register] [Accepted: 11/18/2020] [Indexed: 12/12/2022] Open
Abstract
Protein O-GlcNAcylation is a nutrient-related post-translational modification that, since its discovery some 30 years ago, has been associated with the development of neurodegenerative diseases. As reported in Alzheimer's disease (AD), flaws in the cerebral glucose uptake translate into reduced hexosamine biosynthetic pathway flux and subsequently lead to aberrant protein O-GlcNAcylation. Notably, the reduction of O-GlcNAcylated proteins involves also tau and APP, thus promoting their aberrant phosphorylation in AD brain and the onset of AD pathological markers. Down syndrome (DS) individuals are characterized by the early development of AD by the age of 60 and, although the two conditions present the same pathological hallmarks and share the alteration of many molecular mechanisms driving brain degeneration, no evidence has been sought on the implication of O-GlcNAcylation in DS pathology. Our study aimed to unravel for the first time the role of protein O-GlcNacylation in DS brain alterations positing the attention of potential trisomy-related mechanisms triggering the aberrant regulation of OGT/OGA cycle. We demonstrate the disruption of O-GlcNAcylation homeostasis, as an effect of altered OGT and OGA regulatory mechanism, and confirm the relevance of O-GlcNAcylation in the appearance of AD hallmarks in the brain of a murine model of DS. Furthermore, we provide evidence for the neuroprotective effects of brain-targeted OGA inhibition. Indeed, the rescue of OGA activity was able to restore protein O-GlcNAcylation, and reduce AD-related hallmarks and decreased protein nitration, possibly as effect of induced autophagy.
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Affiliation(s)
- Ilaria Zuliani
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Chiara Lanzillotta
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Antonella Tramutola
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Antonio Francioso
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Sara Pagnotta
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Eugenio Barone
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Marzia Perluigi
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Fabio Di Domenico
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy.
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30
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Verbič A, Praznik A, Jerala R. A guide to the design of synthetic gene networks in mammalian cells. FEBS J 2020; 288:5265-5288. [PMID: 33289352 DOI: 10.1111/febs.15652] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/06/2020] [Accepted: 11/01/2020] [Indexed: 12/22/2022]
Abstract
Synthetic biology aims to harness natural and synthetic biological parts and engineering them in new combinations and systems, producing novel therapies, diagnostics, bioproduction systems, and providing information on the mechanism of function of biological systems. Engineering cell function requires the rewiring or de novo construction of cell information processing networks. Using natural and synthetic signal processing elements, researchers have demonstrated a wide array of signal sensing, processing and propagation modules, using transcription, translation, or post-translational modification to program new function. The toolbox for synthetic network design is ever-advancing and has still ample room to grow. Here, we review the diversity of synthetic gene networks, types of building modules, techniques of regulation, and their applications.
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Affiliation(s)
- Anže Verbič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Arne Praznik
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Roman Jerala
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
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31
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Wu D, Jin J, Qiu Z, Liu D, Luo H. Functional Analysis of O-GlcNAcylation in Cancer Metastasis. Front Oncol 2020; 10:585288. [PMID: 33194731 PMCID: PMC7653022 DOI: 10.3389/fonc.2020.585288] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 10/06/2020] [Indexed: 12/21/2022] Open
Abstract
One common and reversible type of post-translational modification (PTM) is the addition of O-linked β-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), and its dynamic balance is controlled by O-GlcNAc transferase (OGT) and glycoside hydrolase O-GlcNAcase (OGA) through the addition or removal of O-GlcNAc groups. A large amount of research data confirms that proteins regulated by O-GlcNAcylation play a pivotal role in cells. In particularly, imbalanced levels of OGT and O-GlcNAcylation have been found in various types of cancers. Recently, increasing evidence shows that imbalanced O-GlcNAcylation directly or indirectly impacts the process of cancer metastasis. This review summarizes the current understanding of the influence of O-GlcNAc-proteins on the regulation of cancer metastasis. It will provide a theoretical basis to further elucidate of the molecular mechanisms underlying cancer emergence and progression.
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Affiliation(s)
- Donglu Wu
- School of Clinical Medical, Changchun University of Chinese Medicine, Changchun, China.,Key Laboratory of Effective Components of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China
| | - Jingji Jin
- School of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Zhidong Qiu
- Key Laboratory of Effective Components of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China.,School of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Da Liu
- Key Laboratory of Effective Components of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China.,School of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Haoming Luo
- Key Laboratory of Effective Components of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, China.,School of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
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32
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Protein O-GlcNAcylation Promotes Trophoblast Differentiation at Implantation. Cells 2020; 9:cells9102246. [PMID: 33036308 PMCID: PMC7599815 DOI: 10.3390/cells9102246] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 09/18/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022] Open
Abstract
Embryo implantation begins with blastocyst trophectoderm (TE) attachment to the endometrial epithelium, followed by the breaching of this barrier by TE-derived trophoblast. Dynamic protein modification with O-linked β-N-acetylglucosamine (O-GlcNAcylation) is mediated by O-GlcNAc transferase and O-GlcNAcase (OGA), and couples cellular metabolism to stress adaptation. O-GlcNAcylation is essential for blastocyst formation, but whether there is a role for this system at implantation remains unexplored. Here, we used OGA inhibitor thiamet g (TMG) to induce raised levels of O-GlcNAcylation in mouse blastocysts and human trophoblast cells. In an in vitro embryo implantation model, TMG promoted mouse blastocyst breaching of the endometrial epithelium. TMG reduced expression of TE transcription factors Cdx2, Gata2 and Gata3, suggesting that O-GlcNAcylation stimulated TE differentiation to invasive trophoblast. TMG upregulated transcription factors OVOL1 and GCM1, and cell fusion gene ERVFRD1, in a cell line model of syncytiotrophoblast differentiation from human TE at implantation. Therefore O-GlcNAcylation is a conserved pathway capable of driving trophoblast differentiation. TE and trophoblast are sensitive to physical, chemical and nutritive stress, which can occur as a consequence of maternal pathophysiology or during assisted reproduction, and may lead to adverse neonatal outcomes and associated adult health risks. Further investigation of how O-GlcNAcylation regulates trophoblast populations arising at implantation is required to understand how peri-implantation stress affects reproductive outcomes.
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33
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Gorelik A, van Aalten DMF. Tools for functional dissection of site-specific O-GlcNAcylation. RSC Chem Biol 2020; 1:98-109. [PMID: 34458751 PMCID: PMC8386111 DOI: 10.1039/d0cb00052c] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 05/20/2020] [Indexed: 12/14/2022] Open
Abstract
Protein O-GlcNAcylation is an abundant post-translational modification of intracellular proteins with the monosaccharide N-acetylglucosamine covalently tethered to serines and threonines. Modification of proteins with O-GlcNAc is required for metazoan embryo development and maintains cellular homeostasis through effects on transcription, signalling and stress response. While disruption of O-GlcNAc homeostasis can have detrimental impact on cell physiology and cause various diseases, little is known about the functions of individual O-GlcNAc sites. Most of the sites are modified sub-stoichiometrically which is a major challenge to the dissection of O-GlcNAc function. Here, we discuss the application, advantages and limitations of the currently available tools and technologies utilised to dissect the function of O-GlcNAc on individual proteins and sites in vitro and in vivo. Additionally, we provide a perspective on future developments required to decipher the protein- and site-specific roles of this essential sugar modification.
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Affiliation(s)
- Andrii Gorelik
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee Dundee UK
| | - Daan M F van Aalten
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee Dundee UK
- Institute for Molecular Precision Medicine, Xiangya Hospital, Central South University Changsha China
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34
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Chatham JC, Zhang J, Wende AR. Role of O-Linked N-Acetylglucosamine Protein Modification in Cellular (Patho)Physiology. Physiol Rev 2020; 101:427-493. [PMID: 32730113 DOI: 10.1152/physrev.00043.2019] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In the mid-1980s, the identification of serine and threonine residues on nuclear and cytoplasmic proteins modified by a N-acetylglucosamine moiety (O-GlcNAc) via an O-linkage overturned the widely held assumption that glycosylation only occurred in the endoplasmic reticulum, Golgi apparatus, and secretory pathways. In contrast to traditional glycosylation, the O-GlcNAc modification does not lead to complex, branched glycan structures and is rapidly cycled on and off proteins by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. Since its discovery, O-GlcNAcylation has been shown to contribute to numerous cellular functions, including signaling, protein localization and stability, transcription, chromatin remodeling, mitochondrial function, and cell survival. Dysregulation in O-GlcNAc cycling has been implicated in the progression of a wide range of diseases, such as diabetes, diabetic complications, cancer, cardiovascular, and neurodegenerative diseases. This review will outline our current understanding of the processes involved in regulating O-GlcNAc turnover, the role of O-GlcNAcylation in regulating cellular physiology, and how dysregulation in O-GlcNAc cycling contributes to pathophysiological processes.
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Affiliation(s)
- John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Jianhua Zhang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Adam R Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
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35
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Targeting O-GlcNAcylation to develop novel therapeutics. Mol Aspects Med 2020; 79:100885. [PMID: 32736806 DOI: 10.1016/j.mam.2020.100885] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 04/21/2020] [Accepted: 07/21/2020] [Indexed: 12/13/2022]
Abstract
O-linked β-D-N-acetylglucosamine (O-GlcNAc) is an abundant post-translational modification (PTM) that modifies the serine or threonine residues of thousands of proteins in the nucleus, cytoplasm and mitochondria. Being a major "nutrient sensor" in cells, the O-GlcNAc pathway is sensitive to cellular metabolic states. Extensive crosstalk is observed between O-GlcNAcylation and protein phosphorylation. O-GlcNAc regulates protein functions at multiple levels, including enzymatic activity, transcriptional activity, subcellular localization, intermolecular interactions and degradation. Abnormal O-GlcNAcylation is associated with many human diseases including cancer, diabetes and neurodegenerative diseases. Though research on O-GlcNAc is still in its infantry, accumulating evidence suggest O-GlcNAcylation to be a promising therapeutic target. In this review, we briefly discuss the basic features of this PTM, the O-GlcNAc signaling pathway, its regulatory functions on different proteins, and its involvement in human diseases. We hope this review will provide insights to researchers who study human disease, as well as researchers who are interested in the fundamental roles of O-GlcNAcylation in all cells.
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36
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Ju Kim E. O‐GlcNAc Transferase: Structural Characteristics, Catalytic Mechanism and Small‐Molecule Inhibitors. Chembiochem 2020; 21:3026-3035. [DOI: 10.1002/cbic.202000194] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/07/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Eun Ju Kim
- Department of Science Education-Chemistry Major Daegu University Gyeongsan-si, GyeongBuk 712-714 South Korea
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37
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Abstract
The Hippo pathway plays a crucial role in maintaining tissue homeostasis. Generally, activated Hippo pathway effectors, YAP/TAZ, induce the transcription of their negative regulators, NF2 and LATS2, and this negative feedback loop maintains homeostasis of the Hippo pathway. However, YAP and TAZ are consistently hyperactivated in various cancer cells, enhancing tumor growth. Our study found that LATS2, a direct-inhibiting kinase of YAP/TAZ and a core component of the negative feedback loop in the Hippo pathway, is modified with O-GlcNAc. LATS2 O-GlcNAcylation inhibited its activity by interrupting the interaction with the MOB1 adaptor protein, thereby activating YAP and TAZ to promote cell proliferation. Thus, our study suggests that LATS2 O-GlcNAcylation is deeply involved in Hippo pathway dysregulation in cancer cells. The Hippo pathway controls organ size and tissue homeostasis by regulating cell proliferation and apoptosis. The LATS-mediated negative feedback loop prevents excessive activation of the effectors YAP/TAZ, maintaining homeostasis of the Hippo pathway. YAP and TAZ are hyperactivated in various cancer cells which lead to tumor growth. Aberrantly increased O-GlcNAcylation has recently emerged as a cause of hyperactivation of YAP in cancer cells. However, the mechanism, which induces hyperactivation of TAZ and blocks LATS-mediated negative feedback, remains to be elucidated in cancer cells. This study found that in breast cancer cells, abnormally increased O-GlcNAcylation hyperactivates YAP/TAZ and inhibits LATS2, a direct negative regulator of YAP/TAZ. LATS2 is one of the newly identified O-GlcNAcylated components in the MST-LATS kinase cascade. Here, we found that O-GlcNAcylation at LATS2 Thr436 interrupted its interaction with the MOB1 adaptor protein, which connects MST to LATS2, leading to activation of YAP/TAZ by suppressing LATS2 kinase activity. LATS2 is a core component in the LATS-mediated negative feedback loop. Thus, this study suggests that LATS2 O-GlcNAcylation is deeply involved in tumor growth by playing a critical role in dysregulation of the Hippo pathway in cancer cells.
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Kim HY, Park M, Kang C, Heo W, Yoon SM, Lee J, Kim JY. O-GlcNAcylation of light chain serine 12 mediates rituximab production doubled by thiamet G. Bioprocess Biosyst Eng 2020; 43:863-875. [PMID: 31980903 DOI: 10.1007/s00449-020-02282-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 01/07/2020] [Indexed: 10/25/2022]
Abstract
O-Glycosylation occurs in recombinant proteins produced by CHO cells, but this phenomenon has not been studied extensively. Here, we report that rituximab is an O-linked N-acetyl-glucosaminylated (O-GlcNAcylated) protein and the production of rituximab is increased by thiamet G, an inhibitor of O-GlcNAcase. The production of rituximab doubled with OGA inhibition and decreased with O-GlcNAc transferase inhibition. O-GlcNAc-specific antibody and metabolic labelling with azidO-GlcNAc confirmed the increased O-GlcNAcylation with thiamet G. Protein mass analysis revealed that serine 7, 12, and 14 of the rituximab light chain were O-GlcNAcylated. S12A mutation of the light chain decreased rituximab stability and failed to increase the production with thiamet G without any significant changes of mRNA level. Cytotoxicity and thermal stability assays confirmed that there were no differences in the biological and physical properties of rituximab produced by thiamet G treatment. Therefore, thiamet G treatment improves the production of rituximab without significantly altering its function.
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Affiliation(s)
- Hye-Yeon Kim
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 03080, Korea
| | - Minseong Park
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 03080, Korea
| | - Choeun Kang
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 03080, Korea
| | - Woon Heo
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 03080, Korea
| | - Sei Mee Yoon
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, 21983, Republic of Korea
| | - Jinu Lee
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, 21983, Republic of Korea.
| | - Joo Young Kim
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 03080, Korea.
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Qin W, Xie Z, Wang J, Ou G, Wang C, Chen X. Chemoproteomic Profiling of O-GlcNAcylation in Caenorhabditis elegans. Biochemistry 2019; 59:3129-3134. [DOI: 10.1021/acs.biochem.9b00622] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | - Zhongyun Xie
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
| | | | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
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40
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King DT, Males A, Davies GJ, Vocadlo DJ. Molecular mechanisms regulating O-linked N-acetylglucosamine (O-GlcNAc)-processing enzymes. Curr Opin Chem Biol 2019; 53:131-144. [PMID: 31654859 DOI: 10.1016/j.cbpa.2019.09.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 09/04/2019] [Accepted: 09/09/2019] [Indexed: 12/28/2022]
Abstract
The post-translational modification of proteins by O-linked N-acetylglucosamine (O-GlcNAc) dynamically programmes cellular physiology to maintain homoeostasis and tailor biochemical pathways to meet context-dependent cellular needs. Despite diverse roles of played by O-GlcNAc, only two enzymes act antagonistically to govern its cycling; O-GlcNAc transferase installs the monosaccharide on target proteins, and O-GlcNAc hydrolase removes it. The recent literature has exposed a network of mechanisms regulating these two enzymes to choreograph global, and target-specific, O-GlcNAc cycling in response to cellular stress and nutrient availability. Herein, we amalgamate these emerging mechanisms from a structural and molecular perspective to explore how the cell exerts fine control to regulate O-GlcNAcylation of diverse proteins in a selective fashion.
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Affiliation(s)
- Dustin T King
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada; Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
| | - Alexandra Males
- Department of Chemistry, University of York, York, YO10 5DD, England
| | - Gideon J Davies
- Department of Chemistry, University of York, York, YO10 5DD, England
| | - David J Vocadlo
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada; Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada.
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41
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Liu L, Li L, Ma C, Shi Y, Liu C, Xiao Z, Zhang Y, Tian F, Gao Y, Zhang J, Ying W, Wang PG, Zhang L. O-GlcNAcylation of Thr 12/Ser 56 in short-form O-GlcNAc transferase (sOGT) regulates its substrate selectivity. J Biol Chem 2019; 294:16620-16633. [PMID: 31527085 DOI: 10.1074/jbc.ra119.009085] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 09/11/2019] [Indexed: 02/05/2023] Open
Abstract
O-GlcNAcylation is a ubiquitous protein glycosylation playing different roles on variant proteins. O-GlcNAc transferase (OGT) is the unique enzyme responsible for the sugar addition to nucleocytoplasmic proteins. Recently, multiple O-GlcNAc sites have been observed on short-form OGT (sOGT) and nucleocytoplasmic OGT (ncOGT), both of which locate in the nucleus and cytoplasm in cell. Moreover, O-GlcNAcylation of Ser389 in ncOGT (1036 amino acids) affects its nuclear translocation in HeLa cells. To date, the major O-GlcNAcylation sites and their roles in sOGT remain unknown. Here, we performed LC-MS/MS and mutational analyses to seek the major O-GlcNAcylation site on sOGT. We identified six O-GlcNAc sites in the tetratricopeptide repeat domain in sOGT, with Thr12 and Ser56 being two "key" sites. Thr12 is a dominant O-GlcNAcylation site, whereas the modification of Ser56 plays a role in regulating sOGT O-GlcNAcylation, partly through Thr12 In vitro activity and pulldown assays demonstrated that O-GlcNAcylation does not affect sOGT activity but does affect sOGT-interacting proteins. In HEK293T cells, S56A bound to and hence glycosylated more proteins in contrast to T12A and WT sOGT. By proteomic and bioinformatics analyses, we found that T12A and S56A differed in substrate proteins (e.g. HNRNPU and PDCD6IP), which eventually affected cell cycle progression and/or cell proliferation. These findings demonstrate that O-GlcNAcylation modulates sOGT substrate selectivity and affects its role in the cell. The data also highlight the regulatory role of O-GlcNAcylation at Thr12 and Ser56.
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Affiliation(s)
- Li Liu
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
| | - Ling Li
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
| | - Cheng Ma
- Center for Diagnostics and Therapeutics, Department of Chemistry, Georgia State University, Atlanta, Georgia 30303
| | - Yangde Shi
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
| | - Congcong Liu
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
| | - Zikang Xiao
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
| | - Yong Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing 102206, China.,West China-Washington Mitochondria and Metabolism Research Center, Key Laboratory of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Fang Tian
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing 102206, China
| | - Yang Gao
- School of medicine, Nankai University, Tianjin 300071, China
| | - Jie Zhang
- School of medicine, Nankai University, Tianjin 300071, China
| | - Wantao Ying
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing 102206, China
| | - Peng George Wang
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China.,Center for Diagnostics and Therapeutics, Department of Chemistry, Georgia State University, Atlanta, Georgia 30303
| | - Lianwen Zhang
- College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300353, China
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Zachara NE. Critical observations that shaped our understanding of the function(s) of intracellular glycosylation (O-GlcNAc). FEBS Lett 2018; 592:3950-3975. [PMID: 30414174 DOI: 10.1002/1873-3468.13286] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 12/30/2022]
Abstract
Almost 100 years after the first descriptions of proteins conjugated to carbohydrates (mucins), several studies suggested that glycoproteins were not restricted to the serum, extracellular matrix, cell surface, or endomembrane system. In the 1980s, key data emerged demonstrating that intracellular proteins were modified by monosaccharides of O-linked β-N-acetylglucosamine (O-GlcNAc). Subsequently, this modification was identified on thousands of proteins that regulate cellular processes as diverse as protein aggregation, localization, post-translational modifications, activity, and interactions. In this Review, we will highlight critical discoveries that shaped our understanding of the molecular events underpinning the impact of O-GlcNAc on protein function, the role that O-GlcNAc plays in maintaining cellular homeostasis, and our understanding of the mechanisms that regulate O-GlcNAc-cycling.
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Affiliation(s)
- Natasha E Zachara
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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43
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Yin J, Wang Q, Hou S, Bao L, Yao W, Gao X. Potent Protein Delivery into Mammalian Cells via a Supercharged Polypeptide. J Am Chem Soc 2018; 140:17234-17240. [DOI: 10.1021/jacs.8b10299] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jun Yin
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Qun Wang
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Shan Hou
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Lichen Bao
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Wenbing Yao
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Xiangdong Gao
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
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A novel somatic mutation of SIN3A detected in breast cancer by whole-exome sequencing enhances cell proliferation through ERα expression. Sci Rep 2018; 8:16000. [PMID: 30375428 PMCID: PMC6207735 DOI: 10.1038/s41598-018-34290-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 10/12/2018] [Indexed: 12/21/2022] Open
Abstract
Breast cancer is the most frequent tumor in women, and in nearly two-thirds of cases, the tumors express estrogen receptor α (ERα, encoded by ESR1). Here, we performed whole-exome sequencing of 16 breast cancer tissues classified according to ESR1 expression and 12 samples of whole blood, and detected 310 somatic mutations in cancer tissues with high levels of ESR1 expression. Of the somatic mutations validated by a different deep sequencer, a novel nonsense somatic mutation, c.2830 C>T; p.Gln944*, in transcriptional regulator switch-independent 3 family member A (SIN3A) was detected in breast cancer of a patient. Part of the mutant protein localized in the cytoplasm in contrast to the nuclear localization of ERα, and induced a significant increase in ESR1 mRNA. The SIN3A mutation obviously enhanced MCF7 cell proliferation. In tissue sections from the breast cancer patient with the SIN3A c.2830 C>T mutation, cytoplasmic SIN3A localization was detected within the tumor regions where nuclear enlargement was observed. The reduction in SIN3A mRNA correlates with the recurrence of ER-positive breast cancers on Kaplan-Meier plots. These observations reveal that the SIN3A mutation has lost its transcriptional repression function due to its cytoplasmic localization, and that this repression may contribute to the progression of breast cancer.
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Tramutola A, Sharma N, Barone E, Lanzillotta C, Castellani A, Iavarone F, Vincenzoni F, Castagnola M, Butterfield DA, Gaetani S, Cassano T, Perluigi M, Di Domenico F. Proteomic identification of altered protein O-GlcNAcylation in a triple transgenic mouse model of Alzheimer's disease. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3309-3321. [PMID: 30031227 DOI: 10.1016/j.bbadis.2018.07.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/22/2018] [Accepted: 07/16/2018] [Indexed: 12/23/2022]
Abstract
PET scan analysis demonstrated the early reduction of cerebral glucose metabolism in Alzheimer disease (AD) patients that can make neurons vulnerable to damage via the alteration of the hexosamine biosynthetic pathway (HBP). Defective HBP leads to flawed protein O-GlcNAcylation coupled, by a mutual inverse relationship, with increased protein phosphorylation on Ser/Thr residues. Altered O-GlcNAcylation of Tau and APP have been reported in AD and is closely related with pathology onset and progression. In addition, type 2 diabetes patients show an altered O-GlcNAcylation/phosphorylation that might represent a link between metabolic defects and AD progression. Our study aimed to decipher the specific protein targets of altered O-GlcNAcylation in brain of 12-month-old 3×Tg-AD mice compared with age-matched non-Tg mice. Hence, we analysed the global O-GlcNAc levels, the levels and activity of OGT and OGA, the enzymes controlling its cycling and protein specific O-GlcNAc levels using a bi-dimensional electrophoresis (2DE) approach. Our data demonstrate the alteration of OGT and OGA activation coupled with the decrease of total O-GlcNAcylation levels. Data from proteomics analysis led to the identification of several proteins with reduced O-GlcNAcylation levels, which belong to key pathways involved in the progression of AD such as neuronal structure, protein degradation and glucose metabolism. In parallel, we analysed the O-GlcNAcylation/phosphorylation ratio of IRS1 and AKT, whose alterations may contribute to insulin resistance and reduced glucose uptake. Our findings may contribute to better understand the role of altered protein O-GlcNAcylation profile in AD, by possibly identifying novel mechanisms of disease progression related to glucose hypometabolism.
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Affiliation(s)
- Antonella Tramutola
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Nidhi Sharma
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Eugenio Barone
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy; Universidad Autònoma de Chile, Instituto de Ciencias Biomédicas, Facultad de alud, Providencia, Santiago, Chile
| | - Chiara Lanzillotta
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Andrea Castellani
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Federica Iavarone
- Institute of Biochemistry and Clinical Biochemistry, Catholic University, Rome, Italy
| | - Federica Vincenzoni
- Institute of Biochemistry and Clinical Biochemistry, Catholic University, Rome, Italy
| | - Massimo Castagnola
- Institute of Biochemistry and Clinical Biochemistry, Catholic University, Rome, Italy
| | - D Allan Butterfield
- Department of Chemistry and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Silvana Gaetani
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Rome, Italy
| | - Tommaso Cassano
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Marzia Perluigi
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Fabio Di Domenico
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy.
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46
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Laarse SAM, Leney AC, Heck AJR. Crosstalk between phosphorylation and O‐Glc
NA
cylation: friend or foe. FEBS J 2018; 285:3152-3167. [DOI: 10.1111/febs.14491] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/27/2018] [Accepted: 04/26/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Saar A. M. Laarse
- Biomolecular Mass Spectrometry and Proteomics Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands
- Netherlands Proteomics Centre Utrecht The Netherlands
| | - Aneika C. Leney
- Biomolecular Mass Spectrometry and Proteomics Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands
- Netherlands Proteomics Centre Utrecht The Netherlands
| | - Albert J. R. Heck
- Biomolecular Mass Spectrometry and Proteomics Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences Utrecht University The Netherlands
- Netherlands Proteomics Centre Utrecht The Netherlands
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47
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Shin H, Cha HJ, Na K, Lee MJ, Cho JY, Kim CY, Kim EK, Kang CM, Kim H, Paik YK. O-GlcNAcylation of the Tumor Suppressor FOXO3 Triggers Aberrant Cancer Cell Growth. Cancer Res 2018; 78:1214-1224. [DOI: 10.1158/0008-5472.can-17-3512] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 12/22/2017] [Accepted: 12/27/2017] [Indexed: 12/29/2022]
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Ong Q, Han W, Yang X. O-GlcNAc as an Integrator of Signaling Pathways. Front Endocrinol (Lausanne) 2018; 9:599. [PMID: 30464755 PMCID: PMC6234912 DOI: 10.3389/fendo.2018.00599] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/20/2018] [Indexed: 12/03/2022] Open
Abstract
O-GlcNAcylation is an important posttranslational modification governed by a single pair of enzymes-O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). These two enzymes mediate the dynamic cycling of O-GlcNAcylation on a wide variety of cytosolic, nuclear and mitochondrial proteins in a nutrient- and stress-responsive fashion. While cellular functions of O-GlcNAcylation have been emerging, little is known regarding the precise mechanisms how the enzyme pair senses the environmental cues to elicit molecular and physiological changes. In this review, we discuss how the OGT/OGA pair acts as a metabolic sensor that integrates signaling pathways, given their capability of receiving signaling inputs from various partners, targeting multiple substrates with spatiotemporal specificity and translocating to different parts of the cell. We also discuss how the pair maintains homeostatic signaling within the cell and its physiological relevance. A better understanding of the mechanisms of OGT/OGA action would enable us to derive therapeutic benefits of resetting cellular O-GlcNAc levels within an optimal range.
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Affiliation(s)
- Qunxiang Ong
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, United States
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT, United States
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, United States
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Weiping Han
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Xiaoyong Yang
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, United States
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT, United States
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, United States
- *Correspondence: Xiaoyong Yang
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The Role of Stress-Induced O-GlcNAc Protein Modification in the Regulation of Membrane Transport. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:1308692. [PMID: 29456783 PMCID: PMC5804373 DOI: 10.1155/2017/1308692] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/03/2017] [Indexed: 02/06/2023]
Abstract
O-linked N-acetylglucosamine (O-GlcNAc) is a posttranslational modification that is increasingly recognized as a signal transduction mechanism. Unlike other glycans, O-GlcNAc is a highly dynamic and reversible process that involves the addition and removal of a single N-acetylglucosamine molecule to Ser/Thr residues of proteins. UDP-GlcNAc—the direct substrate for O-GlcNAc modification—is controlled by the rate of cellular metabolism, and thus O-GlcNAc is dependent on substrate availability. Serving as a feedback mechanism, O-GlcNAc influences the regulation of insulin signaling and glucose transport. Besides nutrient sensing, O-GlcNAc was also implicated in the regulation of various physiological and pathophysiological processes. Due to improvements of mass spectrometry techniques, more than one thousand proteins were detected to carry the O-GlcNAc moiety; many of them are known to participate in the regulation of metabolites, ions, or protein transport across biological membranes. Recent studies also indicated that O-GlcNAc is involved in stress adaptation; overwhelming evidences suggest that O-GlcNAc levels increase upon stress. O-GlcNAc elevation is generally considered to be beneficial during stress, although the exact nature of its protective effect is not understood. In this review, we summarize the current data regarding the oxidative stress-related changes of O-GlcNAc levels and discuss the implications related to membrane trafficking.
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50
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O-GlcNAc cycling and the regulation of nucleocytoplasmic dynamics. Biochem Soc Trans 2017; 45:427-436. [DOI: 10.1042/bst20160171] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/05/2017] [Accepted: 02/09/2017] [Indexed: 01/01/2023]
Abstract
The dynamic carbohydrate post-translational modification (PTM) O-linked β-N-acetyl glucosamine (O-GlcNAc) is found on thousands of proteins throughout the nucleus and cytoplasm, and rivals phosphorylation in terms of the number of substrates and pathways influenced. O-GlcNAc is highly conserved and essential in most organisms, with disruption of O-GlcNAc cycling linked to diseases ranging from cancer to neurodegeneration. Nuclear pore proteins were the first identified O-GlcNAc-modified substrates, generating intense and ongoing interest in understanding the role of O-GlcNAc cycling in nuclear pore complex structure and function. Recent advances in detecting and altering O-GlcNAcylation levels have provided insights into many mechanisms by which O-GlcNAcylation influences the nucleocytoplasmic localization and stability of protein targets. The emerging view is that the multifunctional enzymes of O-GlcNAc cycling are critical nutrient-sensing components of a complex network of signaling cascades involving multiple PTMs. Furthermore, O-GlcNAc plays a role in maintaining the structural integrity of the nuclear pore and regulating its function as the gatekeeper of nucleocytoplasmic trafficking.
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