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Wardlaw CP, Petrini JH. ISG15: A link between innate immune signaling, DNA replication, and genome stability. Bioessays 2023; 45:e2300042. [PMID: 37147792 PMCID: PMC10473822 DOI: 10.1002/bies.202300042] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/07/2023]
Abstract
Interferon stimulated gene 15 (ISG15) encodes a ubiquitin-like protein that is highly induced upon activation of interferon signaling and cytoplasmic DNA sensing pathways. As part of the innate immune system ISG15 acts to inhibit viral replication and particle release via the covalent conjugation to both viral and host proteins. Unlike ubiquitin, unconjugated ISG15 also functions as an intracellular and extra-cellular signaling molecule to modulate the immune response. Several recent studies have shown ISG15 to also function in a diverse array of cellular processes and pathways outside of the innate immune response. This review explores the role of ISG15 in maintaining genome stability, particularly during DNA replication, and how this relates to cancer biology. It puts forth the hypothesis that ISG15, along with DNA sensors, function within a DNA replication fork surveillance pathway to help maintain genome stability.
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Affiliation(s)
| | - John H.J. Petrini
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
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2
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Wang Z, Li T, Gong Z, Xie J. Role of ISG15 post-translational modification in immunity against Mycobacterium tuberculosis infection. Cell Signal 2022; 94:110329. [PMID: 35390466 DOI: 10.1016/j.cellsig.2022.110329] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 11/30/2022]
Abstract
ISG15 encoded by a type I interferon (IFN) inducible gene mediates an important cellular process called ISGylation. ISGylation emerges as a powerful host tactic against intracellular pathogens like Mycobacterium tuberculosis (Mtb). However, the exact role of ISGylation in immunity remains elusive. To shed light on how ISGylation, which is both interesting and complex, participates in immunity against Mtb, this manuscript summarized the current knowledge about the structural characteristics and targets of ISG15 and how ISGylation cross-talks with other host post-translational modifications to exert its effect.
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Affiliation(s)
- Zilu Wang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Tongxin Li
- Chongqing Public Health Medical Center, Southwest University Public Health Hospital, central laboratory Chongqing, 400030, China
| | - Zhen Gong
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
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3
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Jurczyszak D, Manganaro L, Buta S, Gruber C, Martin-Fernandez M, Taft J, Patel RS, Cipolla M, Alshammary H, Mulder LCF, Sachidanandam R, Bogunovic D, Simon V. ISG15 deficiency restricts HIV-1 infection. PLoS Pathog 2022; 18:e1010405. [PMID: 35333911 PMCID: PMC8986114 DOI: 10.1371/journal.ppat.1010405] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 04/06/2022] [Accepted: 02/28/2022] [Indexed: 01/01/2023] Open
Abstract
Type I interferons (IFN-Is) are a group of potent inflammatory and antiviral cytokines. They induce IFN stimulated genes (ISGs), which act as proinflammatory mediators, antiviral effectors, and negative regulators of the IFN-I signaling cascade itself. One such regulator is interferon stimulated gene 15 (ISG15). Humans with complete ISG15 deficiency express persistently elevated levels of ISGs, and consequently, exhibit broad spectrum resistance to viral infection. Here, we demonstrate that IFN-I primed fibroblasts derived from ISG15-deficient individuals are more resistant to infection with single-cycle HIV-1 compared to healthy control fibroblasts. Complementation with both wild-type (WT) ISG15 and ISG15ΔGG (incapable of ISGylation while retaining negative regulation activity) was sufficient to reverse this phenotype, restoring susceptibility to infection to levels comparable to WT cells. Furthermore, CRISPR-edited ISG15ko primary CD4+ T cells were less susceptible to HIV-1 infection compared to cells treated with non-targeting controls. Transcriptome analysis of these CRISPR-edited ISG15ko primary CD4+ T cells recapitulated the ISG signatures of ISG15 deficient patients. Taken together, we document that the increased broad-spectrum viral resistance in ISG15-deficiency also extends to HIV-1 and is driven by a combination of T-cell-specific ISGs, with both known and unknown functions, predicted to target HIV-1 replication at multiple steps. Type I interferons (IFN-Is) are a group of potent inflammatory and antiviral agents. They induce IFN stimulated genes (ISGs), which perform downstream functions to resolve viral infection, mediate the inflammatory response, as well as negatively regulate the IFN-I signaling cascade to prevent hyperinflammation. One such negative regulator is interferon stimulated gene 15 (ISG15). Humans that lack ISG15 have chronic, low levels of antiviral ISGs, and ensuing broad-spectrum resistance to viral infection. We demonstrate that IFN-I priming of ISG15-deficient cells leads to superior resistance to human immunodeficiency virus 1 (HIV-1) infection compared to IFN-I primed healthy control cells. This is true for fibroblast cell lines, as well as primary CD4+ T cells, the main target of HIV-1. Analysis of the gene expression profiles show that ISG15-knockout CD4+ T cells express similar inflammatory markers as ISG15-deficient patients. Overall, we show that the broad-spectrum viral resistance in ISG15-deficiency extends to HIV-1.
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Affiliation(s)
- Denise Jurczyszak
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Lara Manganaro
- INGM-Istituto Nazionale di Genetica Molecolare, Virology, Milan, Italy
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of MIlan, Milan, Italy
| | - Sofija Buta
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Conor Gruber
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Marta Martin-Fernandez
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Justin Taft
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Roosheel S. Patel
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Melissa Cipolla
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Hala Alshammary
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Lubbertus C. F. Mulder
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Ravi Sachidanandam
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
| | - Dusan Bogunovic
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Center for Inborn Errors of Immunity, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York city, New York, United States of America
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- * E-mail: (DB); (VS)
| | - Viviana Simon
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York City, New York, United States of America
- * E-mail: (DB); (VS)
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4
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Mirzalieva O, Juncker M, Schwartzenburg J, Desai S. ISG15 and ISGylation in Human Diseases. Cells 2022; 11:cells11030538. [PMID: 35159348 PMCID: PMC8834048 DOI: 10.3390/cells11030538] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/18/2022] [Accepted: 01/25/2022] [Indexed: 12/04/2022] Open
Abstract
Type I Interferons (IFNs) induce the expression of >500 genes, which are collectively called ISGs (IFN-stimulated genes). One of the earliest ISGs induced by IFNs is ISG15 (Interferon-Stimulated Gene 15). Free ISG15 protein synthesized from the ISG15 gene is post-translationally conjugated to cellular proteins and is also secreted by cells into the extracellular milieu. ISG15 comprises two ubiquitin-like domains (UBL1 and UBL2), each of which bears a striking similarity to ubiquitin, accounting for its earlier name ubiquitin cross-reactive protein (UCRP). Like ubiquitin, ISG15 harbors a characteristic β-grasp fold in both UBL domains. UBL2 domain has a conserved C-terminal Gly-Gly motif through which cellular proteins are appended via an enzymatic cascade similar to ubiquitylation called ISGylation. ISG15 protein is minimally expressed under physiological conditions. However, its IFN-dependent expression is aberrantly elevated or compromised in various human diseases, including multiple types of cancer, neurodegenerative disorders (Ataxia Telangiectasia and Amyotrophic Lateral Sclerosis), inflammatory diseases (Mendelian Susceptibility to Mycobacterial Disease (MSMD), bacteriopathy and viropathy), and in the lumbar spinal cords of veterans exposed to Traumatic Brain Injury (TBI). ISG15 and ISGylation have both inhibitory and/or stimulatory roles in the etiology and pathogenesis of human diseases. Thus, ISG15 is considered a “double-edged sword” for human diseases in which its expression is elevated. Because of the roles of ISG15 and ISGylation in cancer cell proliferation, migration, and metastasis, conferring anti-cancer drug sensitivity to tumor cells, and its elevated expression in cancer, neurodegenerative disorders, and veterans exposed to TBI, both ISG15 and ISGylation are now considered diagnostic/prognostic biomarkers and therapeutic targets for these ailments. In the current review, we shall cover the exciting journey of ISG15, spanning three decades from the bench to the bedside.
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Affiliation(s)
| | | | | | - Shyamal Desai
- Correspondence: ; Tel.: +1-504-568-4388; Fax: +1-504-568-2093
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Bolado-Carrancio A, Lee M, Ewing A, Muir M, Macleod KG, Gallagher WM, Nguyen LK, Carragher NO, Semple CA, Brunton VG, Caswell PT, von Kriegsheim A. ISGylation drives basal breast tumour progression by promoting EGFR recycling and Akt signalling. Oncogene 2021; 40:6235-6247. [PMID: 34556814 PMCID: PMC8566238 DOI: 10.1038/s41388-021-02017-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/29/2021] [Accepted: 09/10/2021] [Indexed: 02/08/2023]
Abstract
ISG15 is an ubiquitin-like modifier that is associated with reduced survival rates in breast cancer patients. The mechanism by which ISG15 achieves this however remains elusive. We demonstrate that modification of Rab GDP-Dissociation Inhibitor Beta (GDI2) by ISG15 (ISGylation) alters endocytic recycling of the EGF receptor (EGFR) in non-interferon stimulated cells using CRISPR-knock out models for ISGylation. By regulating EGFR trafficking, ISGylation enhances EGFR recycling and sustains Akt-signalling. We further show that Akt signalling positively correlates with levels of ISG15 and its E2-ligase in basal breast cancer cohorts, confirming the link between ISGylation and Akt signalling in human tumours. Persistent and enhanced Akt activation explains the more aggressive tumour behaviour observed in human breast cancers. We show that ISGylation can act as a driver of tumour progression rather than merely being a bystander.
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Affiliation(s)
- Alfonso Bolado-Carrancio
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Martin Lee
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Ailith Ewing
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Morwenna Muir
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Kenneth G Macleod
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - William M Gallagher
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, D4, Republic of Ireland
| | - Lan K Nguyen
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, 3800, Australia
| | - Neil O Carragher
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Colin A Semple
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Valerie G Brunton
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK
| | - Patrick T Caswell
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Alex von Kriegsheim
- Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, UK.
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Juncker M, Kim C, Reed R, Haas A, Schwartzenburg J, Desai S. ISG15 attenuates post-translational modifications of mitofusins and congression of damaged mitochondria in Ataxia Telangiectasia cells. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166102. [PMID: 33617986 DOI: 10.1016/j.bbadis.2021.166102] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 10/22/2022]
Abstract
Mitophagy is defective in several neurodegenerative diseases, including Ataxia Telangiectasia (A-T). However, the molecular mechanism underlying defective mitophagy in A-T is unknown. Literature indicates that damaged mitochondria are transported to the perinuclear region prior to their removal via mitophagy. Our previous work has indicated that conjugation of SUMO2 (Small Ubiquitin-like Modifier 2) to mitofusins (Mfns) may be necessary for congression of mitochondria into SUMO2-/ubiquitin-/LC3-positive compact structures resembling mito-aggresomes at the perinuclear region in CCCP-treated HEK293 cells. Here, we demonstrate that Mfns are SUMOylated, and mitochondria are transported to the perinuclear region; however, mitochondria fail to congress into mito-aggresome-like structures in CCCP-treated A-T cells. Defect in mitochondrial congression is causally related to constitutively elevated ISG15 (Interferon-Stimulated Gene 15), an antagonist of the ubiquitin pathway, in A-T cells. Suppression of the ISG15 pathway restores mitochondrial congression, reduce oxidative stress, and level of unhealthy mitochondria, which is suggestive of restoration of mitophagy in A-T cells. ISG15 is also constitutively elevated and mitophagy is defective in Amytrophic Lateral Sclerosis (ALS). The constitutively elevated ISG15 pathway therefore appears to be a common unifying biochemical mechanism underlying defective mitophagy in neurodegenerative disorders thus, implying the broader significance of our findings, and suggest the potential role of ISG15 inhibitors in their treatment.
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Affiliation(s)
- Meredith Juncker
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Catherine Kim
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Ryan Reed
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Arthur Haas
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Joshua Schwartzenburg
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Shyamal Desai
- Department of Biochemistry & Molecular Biology, LSU Health Sciences Center-School of Medicine, 1901 Perdido Street, New Orleans, LA 70112, USA.
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Abstract
Post-translational modifications of cellular substrates with ubiquitin and ubiquitin-like proteins (UBLs), including ubiquitin, SUMOs, and neural precursor cell-expressed developmentally downregulated protein 8, play a central role in regulating many aspects of cell biology. The UBL conjugation cascade is initiated by a family of ATP-dependent enzymes termed E1 activating enzymes and executed by the downstream E2-conjugating enzymes and E3 ligases. Despite their druggability and their key position at the apex of the cascade, pharmacologic modulation of E1s with potent and selective drugs has remained elusive until 2009. Among the eight E1 enzymes identified so far, those initiating ubiquitylation (UBA1), SUMOylation (SAE), and neddylation (NAE) are the most characterized and are implicated in various aspects of cancer biology. To date, over 40 inhibitors have been reported to target UBA1, SAE, and NAE, including the NAE inhibitor pevonedistat, evaluated in more than 30 clinical trials. In this Review, we discuss E1 enzymes, the rationale for their therapeutic targeting in cancer, and their different inhibitors, with emphasis on the pharmacologic properties of adenosine sulfamates and their unique mechanism of action, termed substrate-assisted inhibition. Moreover, we highlight other less-characterized E1s-UBA6, UBA7, UBA4, UBA5, and autophagy-related protein 7-and the opportunities for targeting these enzymes in cancer. SIGNIFICANCE STATEMENT: The clinical successes of proteasome inhibitors in cancer therapy and the emerging resistance to these agents have prompted the exploration of other signaling nodes in the ubiquitin-proteasome system including E1 enzymes. Therefore, it is crucial to understand the biology of different E1 enzymes, their roles in cancer, and how to translate this knowledge into novel therapeutic strategies with potential implications in cancer treatment.
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Affiliation(s)
- Samir H Barghout
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada (S.H.B., A.D.S.); Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada (S.H.B., A.D.S.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, Egypt (S.H.B.)
| | - Aaron D Schimmer
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada (S.H.B., A.D.S.); Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada (S.H.B., A.D.S.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, Egypt (S.H.B.)
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8
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Abstract
The host response to viral infection includes the induction of type I interferons and the subsequent upregulation of hundreds of interferon-stimulated genes. Ubiquitin-like protein ISG15 is an interferon-induced protein that has been implicated as a central player in the host antiviral response. Over the past 15 years, efforts to understand how ISG15 protects the host during infection have revealed that its actions are diverse and pathogen-dependent. In this Review, we describe new insights into how ISG15 directly inhibits viral replication and discuss the recent finding that ISG15 modulates the host damage and repair response, immune response and other host signalling pathways. We also explore the viral immune-evasion strategies that counteract the actions of ISG15. These findings are integrated with a discussion of the recent identification of ISG15-deficient individuals and a cellular receptor for ISG15 that provides new insights into how ISG15 shapes the host response to viral infection. Ubiquitin-like protein ISG15 is an interferon-induced protein that has been implicated as a central player in the host antiviral response. In this Review, Perng and Lenschow provide new insights into how ISG15 restricts and shapes the host response to viral infection and the viral immune-evasion strategies that counteract ISG15.
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Affiliation(s)
- Yi-Chieh Perng
- Department of Internal Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Deborah J Lenschow
- Department of Internal Medicine, Washington University School of Medicine, St Louis, MO, USA. .,Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA.
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9
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Abstract
Many receptor tyrosine kinases (RTKs, such as EGFR, MET) are negatively regulated by ubiquitination and degradation mediated by Cbl proteins, a family of RING finger (RF) ubiquitin ligases (E3s). Loss of Cbl protein function is associated with malignant transformation driven by increased RTK activity. RF E3s, such as the Cbl proteins, interact with a ubiquitin-conjugating enzyme (E2) to confer specificity to the ubiquitination process and direct the transfer of ubiquitin from the E2 to one or more lysines on the target proteins. Using in vitro E3 assays and yeast two-hybrid screens, we found that Ube2d, Ube2e families, Ube2n/2v1, and Ube2w catalyze autoubiquitination of the Cbl protein and Ube2d2, Ube2e1, and Ube 2n/2v1 catalyze Cbl-mediated substrate ubiquitination of the EGFR and SYK. Phosphorylation of the Cbl protein by by Src resulted in increased E3 activity compared to unphosphorylated cbl or Cbl containing a phosphomimetic Y371E mutation. Ubiquitin chain formation depended on the E2 tested with Cbl with Ube2d2 forming both K48 and K63 linked chains, Ube2n/2v1 forming only K63 linked chains, and Ube2w inducing monoubiquitination. In cells, the Ube2d family, Ube2e family, and Ube2n/2v1 contributed to EGFR ubiquitination. Our data suggest that multiple E2s can interact with Cbl and modulate its E3 activity in vitro and in cells.
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10
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UBE2E1 Is Preferentially Expressed in the Cytoplasm of Slow-Twitch Fibers and Protects Skeletal Muscles from Exacerbated Atrophy upon Dexamethasone Treatment. Cells 2018; 7:cells7110214. [PMID: 30453501 PMCID: PMC6262581 DOI: 10.3390/cells7110214] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/09/2018] [Accepted: 11/13/2018] [Indexed: 12/27/2022] Open
Abstract
Skeletal muscle mass is reduced during many diseases or physiological situations (disuse, aging), which results in decreased strength and increased mortality. Muscle mass is mainly controlled by the ubiquitin-proteasome system (UPS), involving hundreds of ubiquitinating enzymes (E2s and E3s) that target their dedicated substrates for subsequent degradation. We recently demonstrated that MuRF1, an E3 ubiquitin ligase known to bind to sarcomeric proteins (telethonin, α-actin, myosins) during catabolic situations, interacts with 5 different E2 enzymes and that these E2-MuRF1 couples are able to target telethonin, a small sarcomeric protein, for degradation. Amongst the E2s interacting with MuRF1, E2E1 was peculiar as the presence of the substrate was necessary for optimal MuRF1-E2E1 interaction. In this work, we focused on the putative role of E2E1 during skeletal muscle atrophy. We found that E2E1 expression was restricted to type I and type IIA muscle fibers and was not detectable in type IIB fibers. This strongly suggests that E2E1 targets are fiber-specific and may be strongly linked to the contractile and metabolic properties of the skeletal muscle. However, E2E1 knockdown was not sufficient for preserving the protein content in C2C12 myotubes subjected to a catabolic state (dexamethasone treatment), suggesting that E2E1 is not involved in the development of muscle atrophy. By contrast, E2E1 knockdown aggravated the atrophying process in both catabolic C2C12 myotubes and the Tibialis anterior muscle of mice, suggesting that E2E1 has a protective effect on muscle mass.
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11
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Albert M, Bécares M, Falqui M, Fernández-Lozano C, Guerra S. ISG15, a Small Molecule with Huge Implications: Regulation of Mitochondrial Homeostasis. Viruses 2018; 10:v10110629. [PMID: 30428561 PMCID: PMC6265978 DOI: 10.3390/v10110629] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 12/12/2022] Open
Abstract
Viruses are responsible for the majority of infectious diseases, from the common cold to HIV/AIDS or hemorrhagic fevers, the latter with devastating effects on the human population. Accordingly, the development of efficient antiviral therapies is a major goal and a challenge for the scientific community, as we are still far from understanding the molecular mechanisms that operate after virus infection. Interferon-stimulated gene 15 (ISG15) plays an important antiviral role during viral infection. ISG15 catalyzes a ubiquitin-like post-translational modification termed ISGylation, involving the conjugation of ISG15 molecules to de novo synthesized viral or cellular proteins, which regulates their stability and function. Numerous biomedically relevant viruses are targets of ISG15, as well as proteins involved in antiviral immunity. Beyond their role as cellular powerhouses, mitochondria are multifunctional organelles that act as signaling hubs in antiviral responses. In this review, we give an overview of the biological consequences of ISGylation for virus infection and host defense. We also compare several published proteomic studies to identify and classify potential mitochondrial ISGylation targets. Finally, based on our recent observations, we discuss the essential functions of mitochondria in the antiviral response and examine the role of ISG15 in the regulation of mitochondrial processes, specifically OXPHOS and mitophagy.
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Affiliation(s)
- Manuel Albert
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
| | - Martina Bécares
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
| | - Michela Falqui
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
| | - Carlos Fernández-Lozano
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
| | - Susana Guerra
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
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12
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Pasupala N, Morrow ME, Que LT, Malynn BA, Ma A, Wolberger C. OTUB1 non-catalytically stabilizes the E2 ubiquitin-conjugating enzyme UBE2E1 by preventing its autoubiquitination. J Biol Chem 2018; 293:18285-18295. [PMID: 30282802 PMCID: PMC6254341 DOI: 10.1074/jbc.ra118.004677] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 09/04/2018] [Indexed: 01/08/2023] Open
Abstract
OTUB1 is a deubiquitinating enzyme that cleaves Lys-48–linked polyubiquitin chains and also regulates ubiquitin signaling through a unique, noncatalytic mechanism. OTUB1 binds to a subset of E2 ubiquitin-conjugating enzymes and inhibits their activity by trapping the E2∼ubiquitin thioester and preventing ubiquitin transfer. The same set of E2s stimulate the deubiquitinating activity of OTUB1 when the E2 is not charged with ubiquitin. Previous studies have shown that, in cells, OTUB1 binds to E2-conjugating enzymes of the UBE2D (UBCH5) and UBE2E families, as well as to UBE2N (UBC13). Cellular roles have been identified for the interaction of OTUB1 with UBE2N and members of the UBE2D family, but not for interactions with UBE2E E2 enzymes. We report here a novel role for OTUB1–E2 interactions in modulating E2 protein ubiquitination. We observe that Otub1−/− knockout mice exhibit late-stage embryonic lethality. We find that OTUB1 depletion dramatically destabilizes the E2-conjugating enzyme UBE2E1 (UBCH6) in both mouse and human OTUB1 knockout cell lines. Of note, this effect is independent of the catalytic activity of OTUB1, but depends on its ability to bind to UBE2E1. We show that OTUB1 suppresses UBE2E1 autoubiquitination in vitro and in cells, thereby preventing UBE2E1 from being targeted to the proteasome for degradation. Taken together, we provide evidence that OTUB1 rescues UBE2E1 from degradation in vivo.
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Affiliation(s)
- Nagesh Pasupala
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185 and
| | - Marie E Morrow
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185 and
| | - Lauren T Que
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185 and
| | - Barbara A Malynn
- the Department of Medicine, University of California San Francisco, San Francisco, California 94117
| | - Averil Ma
- the Department of Medicine, University of California San Francisco, San Francisco, California 94117
| | - Cynthia Wolberger
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185 and.
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13
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Wang Z, Zhu WG, Xu X. Ubiquitin-like modifications in the DNA damage response. Mutat Res 2017; 803-805:56-75. [PMID: 28734548 DOI: 10.1016/j.mrfmmm.2017.07.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/03/2017] [Accepted: 07/03/2017] [Indexed: 12/14/2022]
Abstract
Genomic DNA is damaged at an extremely high frequency by both endogenous and environmental factors. An improper response to DNA damage can lead to genome instability, accelerate the aging process and ultimately cause various human diseases, including cancers and neurodegenerative disorders. The mechanisms that underlie the cellular DNA damage response (DDR) are complex and are regulated at many levels, including at the level of post-translational modification (PTM). Since the discovery of ubiquitin in 1975 and ubiquitylation as a form of PTM in the early 1980s, a number of ubiquitin-like modifiers (UBLs) have been identified, including small ubiquitin-like modifiers (SUMOs), neural precursor cell expressed, developmentally down-regulated 8 (NEDD8), interferon-stimulated gene 15 (ISG15), human leukocyte antigen (HLA)-F adjacent transcript 10 (FAT10), ubiquitin-fold modifier 1 (UFRM1), URM1 ubiquitin-related modifier-1 (URM1), autophagy-related protein 12 (ATG12), autophagy-related protein 8 (ATG8), fan ubiquitin-like protein 1 (FUB1) and histone mono-ubiquitylation 1 (HUB1). All of these modifiers have known roles in the cellular response to various forms of stress, and delineating their underlying molecular mechanisms and functions is fundamental in enhancing our understanding of human disease and longevity. To date, however, the molecular mechanisms and functions of these UBLs in the DDR remain largely unknown. This review summarizes the current status of PTMs by UBLs in the DDR and their implication in cancer diagnosis, therapy and drug discovery.
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Affiliation(s)
- Zhifeng Wang
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China
| | - Wei-Guo Zhu
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China
| | - Xingzhi Xu
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China; Beijing Key Laboratory of DNA Damage Response, Capital Normal University College of Life Sciences, Beijing 100048, China.
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14
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Basters A, Geurink PP, Röcker A, Witting KF, Tadayon R, Hess S, Semrau MS, Storici P, Ovaa H, Knobeloch KP, Fritz G. Structural basis of the specificity of USP18 toward ISG15. Nat Struct Mol Biol 2017; 24:270-278. [PMID: 28165509 PMCID: PMC5405867 DOI: 10.1038/nsmb.3371] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 01/05/2017] [Indexed: 02/03/2023]
Abstract
Protein modification by ubiquitin and ubiquitin-like modifiers (Ubls) is counteracted by ubiquitin proteases and Ubl proteases, collectively termed DUBs. In contrast to other proteases of the ubiquitin-specific protease (USP) family, USP18 shows no reactivity toward ubiquitin but specifically deconjugates the interferon-induced Ubl ISG15. To identify the molecular determinants of this specificity, we solved the crystal structures of mouse USP18 alone and in complex with mouse ISG15. USP18 was crystallized in an open and a closed conformation, thus revealing high flexibility of the enzyme. Structural data, biochemical and mutational analysis showed that only the C-terminal ubiquitin-like domain of ISG15 is recognized and essential for USP18 activity. A critical hydrophobic patch in USP18 interacts with a hydrophobic region unique to ISG15, thus providing evidence that USP18's ISG15 specificity is mediated by a small interaction interface. Our results may provide a structural basis for the development of new drugs modulating ISG15 linkage.
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Affiliation(s)
- Anja Basters
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany
| | - Paul P Geurink
- Department of Chemical Immunology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, Netherlands
| | - Annika Röcker
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany
| | - Katharina F Witting
- Department of Chemical Immunology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, Netherlands
| | - Roya Tadayon
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany.,Hermann-Staudinger-Graduate school, University of Freiburg, Hebelstrasse 27, 79104 Freiburg, Germany
| | - Sandra Hess
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany
| | - Marta S Semrau
- Structural Biology Laboratory, Elettra Sincrotrone Trieste S.C.p.A., SS 14 - km 163,5 in AREA Science Park, 34149 Trieste, Italy
| | - Paola Storici
- Structural Biology Laboratory, Elettra Sincrotrone Trieste S.C.p.A., SS 14 - km 163,5 in AREA Science Park, 34149 Trieste, Italy
| | - Huib Ovaa
- Department of Chemical Immunology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, Netherlands
| | - Klaus-Peter Knobeloch
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany
| | - Günter Fritz
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany, Breisacherstraße 64, 79106 Freiburg, Germany
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15
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Epigenetic downregulation of the ISG15-conjugating enzyme UbcH8 impairs lipolysis and correlates with poor prognosis in nasopharyngeal carcinoma. Oncotarget 2016; 6:41077-91. [PMID: 26506425 PMCID: PMC4747391 DOI: 10.18632/oncotarget.6218] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/20/2015] [Indexed: 12/30/2022] Open
Abstract
We identified the UBE2L6 gene, encoding the ISG15-conjugating enzyme UbcH8, as one gene significantly downregulated by promoter hypermethylation in nasopharyngeal carcinoma (NPC). Reduced expression of the UbcH8 protein correlated with poor outcome in NPC patients. Restored expression of UBE2L6 suppressed proliferation and colony formation in NPC cells, while inducing apoptosis. Of particular interest, we found that aberrant lipid turnover was controlled by UbcH8 in NPC through ISG15-conjugation of valosin-containing protein (VCP). Tumor tissue and NPC cell lines showed conspicuously strong accumulation of lipid droplets (LDs) compared to control nasopharyngeal epithelium and non-cancerous cell lines. We demonstrated that UbcH8 counteracts degradation of adipocyte triglyceride lipase (ATGL), a key enzyme in lipid catabolism.
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16
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Wei X, Li XZ, Zheng X, Jia P, Wang J, Yang X, Yu L, Shi X, Tong G, Liu H. Toll-like receptors and interferon associated immune factors responses to spring viraemia of carp virus infection in common carp (Cyprinus carpio). FISH & SHELLFISH IMMUNOLOGY 2016; 55:568-576. [PMID: 27263115 DOI: 10.1016/j.fsi.2016.05.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 05/29/2016] [Accepted: 05/31/2016] [Indexed: 06/05/2023]
Abstract
Pattern recognition receptor (PRR) toll-like receptors (TLRs), antiviral agent interferon (IFN) and the effector IFN stimulated genes (ISGs) play a fundamental role in the innate immune response against viruses among all vertebrate classes. Common carp is a host for spring viraemia of carp virus (Rhabdovirus carpio, SVCV), which belong to Rhabdoviridae family. The present in-vivo experiment was conducted to investigate the expression of these innate immune factors in early phase as well as during recovery of SVCV infection by real-time quantitative reverse transcriptase polymerase chain reaction. A less lethal SVCV infection was generated in common carp (Cyprinus carpio) and was sampled at 3, 6, 12 h post infection (hpi), 1, 3, 5, 7 and 10 days post infection (dpi). At 3 hpi, the SVCV N gene was detected in all three fish and all three fish showed a relative fold increase of TLR2, TLR3 and TLR7, IFNa1, ISG15 and Vig1. Viral copies rapidly increased at 12 hpi then remained high until 5 dpi. When viral copy numbers were high, a higher expression of immune genes TLR2, TLR3, TLR7, IFNa1, IFNa2, IFNa1S, IFN regulatory factor 3 (IRF3), IRF7, interleukin 1β (IL1β), IL6, IL10, ADAR, ISG15, Mx1, PKR and Vig1 were observed. Viral copies were gradually reduced in 5 to 10 dpi fish, and also the immune response was considerably reduced but remained elevated. A high degree of correlation was observed between immune genes and viral copy number in each of the sampled fish at 12 hpi. The quick and prolonged elevated expression of the immune genes indicates their crucial role in survival of host against SVCV.
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Affiliation(s)
- Xinxian Wei
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China; Guangxi Academy of Fishery Science, Nanning 530021, China
| | - Xiao Zheng Li
- Guangxi Academy of Fishery Science, Nanning 530021, China
| | - Xiaocong Zheng
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China
| | - Peng Jia
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China
| | - Jinjin Wang
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China
| | - Xianle Yang
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Li Yu
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China
| | - Xiujie Shi
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China
| | - Guixiang Tong
- Guangxi Academy of Fishery Science, Nanning 530021, China.
| | - Hong Liu
- Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045, China.
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17
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Zhang J, Shao J, Wu X, Mao Q, Wang Y, Gao F, Kong W, Liang Z. Type I interferon related genes are common genes on the early stage after vaccination by meta-analysis of microarray data. Hum Vaccin Immunother 2015; 11:739-45. [PMID: 25839220 DOI: 10.1080/21645515.2015.1008884] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The objective of this study was to find common immune mechanism across different kinds of vaccines. A meta-analysis of microarray datasets was performed using publicly available microarray Gene Expression Omnibus (GEO) and Array Express data sets of vaccination records. Seven studies (out of 35) were selected for this meta-analysis. A total of 447 chips (145 pre-vaccination and 302 post-vaccination) were included. Significance analysis of microarrays (SAM) program was used for screening differentially expressed genes (DEGs). Functional pathway enrichment for the DEGs was conducted in DAVID Gene Ontology (GO) database. Twenty DEGs were identified, of which 10 up-regulated genes involved immune response. Six of which were type I interferon (IFN) related genes, including LY6E, MX1, OAS3, IFI44L, IFI6 and IFITM3. Ten down-regulated genes mainly mediated negative regulation of cell proliferation and cell motion. Results of a subgroup analysis showed that although the kinds of genes varied widely between days 3 and 7 post vaccination, the pathways between them are basically the same, such as immune response and response to viruses, etc. For an independent verification of these 6 type I IFN related genes, peripheral blood mononuclear cells (PBMCs) were collected at baseline and day 3 after the vaccination from 8 Enterovirus 71(EV71) vaccinees and were assayed by RT-PCR. Results showed that the 6 DEGs were also upregulated in EV71 vaccinees. In summary, meta-analysis methods were used to explore the immune mechanism of vaccines and results indicated that the type I IFN related genes and corresponding pathways were common in early immune responses for different kinds of vaccines.
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Key Words
- CPE, cytopathogenic effect
- DCs, dendritic cells
- DEGs, differentially expressed genes
- EV71, enterovirus 71
- GEO, Gene Expression Omnibus
- GO, gene ontology
- IFN, interferon
- PBMCs, peripheral blood mononuclear cells
- PRRs, pattern recognition receptors
- SAM, significance analysis of microarrays
- TLRs, Toll-like receptors
- immune mechanism
- meta-analysis
- microarray
- type I interferon
- vaccine
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Affiliation(s)
- Junnan Zhang
- a National Institutes for Food and Drug Control ; Beijing , P.R. China
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18
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Boasso A. Type I Interferon at the Interface of Antiviral Immunity and Immune Regulation: The Curious Case of HIV-1. SCIENTIFICA 2013; 2013:580968. [PMID: 24455433 PMCID: PMC3885208 DOI: 10.1155/2013/580968] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 12/10/2013] [Indexed: 06/03/2023]
Abstract
Type I interferon (IFN-I) play a critical role in the innate immune response against viral infections. They actively participate in antiviral immunity by inducing molecular mechanisms of viral restriction and by limiting the spread of the infection, but they also orchestrate the initial phases of the adaptive immune response and influence the quality of T cell immunity. During infection with the human immunodeficiency virus type 1 (HIV-1), the production of and response to IFN-I may be severely altered by the lymphotropic nature of the virus. In this review I consider the different aspects of virus sensing, IFN-I production, signalling, and effects on target cells, with a particular focus on the alterations observed following HIV-1 infection.
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Affiliation(s)
- Adriano Boasso
- Immunology Section, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, UK
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19
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Campbell JA, Lenschow DJ. Emerging roles for immunomodulatory functions of free ISG15. J Interferon Cytokine Res 2013; 33:728-38. [PMID: 24010825 DOI: 10.1089/jir.2013.0064] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Type I interferons (IFNs) exert their effects through the induction of hundreds of IFN-stimulated genes (ISGs), many of which function by inhibiting viral replication and modulating immune responses. ISG15, a di-ubiquitin-like protein, is one of the most abundantly induced ISGs and is critical for control of certain viral and bacterial infections. Like ubiquitin, ISG15 is covalently conjugated to target proteins. In addition, free unconjugated ISG15 is present both intra- and extracellularly. Although much remains to be learned about conjugated ISG15, even less is known about the 2 free forms of ISG15. This article focuses on the role that ISG15 plays during the host response to pathogen challenge, in particular on the recent observations describing the immunomodulatory properties of free ISG15 and its potential implication in disease pathogenesis.
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Affiliation(s)
- Jessica A Campbell
- Department of Internal Medicine, Washington University School of Medicine , St. Louis, Missouri
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20
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Glass C, Wuertzer C, Cui X, Bi Y, Davuluri R, Xiao YY, Wilson M, Owens K, Zhang Y, Perkins A. Global Identification of EVI1 Target Genes in Acute Myeloid Leukemia. PLoS One 2013; 8:e67134. [PMID: 23826213 PMCID: PMC3694976 DOI: 10.1371/journal.pone.0067134] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 05/19/2013] [Indexed: 12/20/2022] Open
Abstract
The ecotropic virus integration site 1 (EVI1) transcription factor is associated with human myeloid malignancy of poor prognosis and is overexpressed in 8-10% of adult AML and strikingly up to 27% of pediatric MLL-rearranged leukemias. For the first time, we report comprehensive genomewide EVI1 binding and whole transcriptome gene deregulation in leukemic cells using a combination of ChIP-Seq and RNA-Seq expression profiling. We found disruption of terminal myeloid differentiation and cell cycle regulation to be prominent in EVI-induced leukemogenesis. Specifically, we identified EVI1 directly binds to and downregulates the master myeloid differentiation gene Cebpe and several of its downstream gene targets critical for terminal myeloid differentiation. We also found EVI1 binds to and downregulates Serpinb2 as well as numerous genes involved in the Jak-Stat signaling pathway. Finally, we identified decreased expression of several ATP-dependent P2X purinoreceptors genes involved in apoptosis mechanisms. These findings provide a foundation for future study of potential therapeutic gene targets for EVI1-induced leukemia.
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Affiliation(s)
- Carolyn Glass
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Charles Wuertzer
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Xiaohui Cui
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Yingtao Bi
- Molecular and Cellular Oncogenesis Program, Center for Systems and Computational Biology The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ramana Davuluri
- Molecular and Cellular Oncogenesis Program, Center for Systems and Computational Biology The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ying-Yi Xiao
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Michael Wilson
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Kristina Owens
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Yi Zhang
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Archibald Perkins
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
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21
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Burks J, Reed RE, Desai SD. ISGylation governs the oncogenic function of Ki-Ras in breast cancer. Oncogene 2013; 33:794-803. [PMID: 23318454 DOI: 10.1038/onc.2012.633] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/27/2012] [Accepted: 11/30/2012] [Indexed: 12/20/2022]
Abstract
Aberrant expression of the oncogenic Kirsten-Ras (Ki-Ras) and interferon-stimulated gene 15 (ISG15) pathways is common in breast and other cancers. However, whether these dysregulated pathways cooperate to promote malignancy is not known. This study links Ki-Ras and ISG15 in a previously unidentified regulatory loop that may underlie malignant transformation of mammary cells. We show that oncogenic Ki-Ras regulates the expression of the ISG15 pathway (free ISG15 and ISG15 conjugates), and ISG15, in turn, stabilizes Ki-Ras protein by inhibiting its targeted degradation via lysosomes in breast cancer cells. Disruption of this loop by silencing either Ki-Ras or the ISG15 pathway restored the disrupted cellular architecture, a hallmark feature of most cancer cells. We also demonstrate that ISG15 and UbcH8 (ISG15-specific conjugating enzyme) shRNAs reversed Ki-Ras mutation-associated phenotypes of cancer cells, such as increased cell proliferation, colony formation, anchorage-independent growth in soft agar, cell migration, and epithelial-mesenchymal transition. As UbcH8-silenced breast cancer cells are devoid of ISG15 conjugates but have free ISG15, our results using UbcH8-silenced cells suggest that ISG15 conjugates, and not free ISG15, contributes to oncogenic Ki-Ras transformation. We have thus identified the conjugated form of ISG15 as a critical downstream mediator of oncogenic Ki-Ras, providing a potential mechanistic link between ISG15 and Ki-Ras-mediated breast tumorigenesis. Our findings, which show that inhibition of the ISGylation reverses the malignant phenotypes of breast cancer cells expressing oncogenic Ki-Ras, support the development of ISG15 conjugation inhibitors for treating breast and also other cancers expressing oncogenic Ki-Ras.
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Affiliation(s)
- J Burks
- Department of Biochemistry and Molecular Biology, LSU Health Science Center-School of Medicine, New Orleans, LA, USA
| | - R E Reed
- Department of Biochemistry and Molecular Biology, LSU Health Science Center-School of Medicine, New Orleans, LA, USA
| | - S D Desai
- Department of Biochemistry and Molecular Biology, LSU Health Science Center-School of Medicine, New Orleans, LA, USA
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22
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Okumura F, Okumura AJ, Uematsu K, Hatakeyama S, Zhang DE, Kamura T. Activation of double-stranded RNA-activated protein kinase (PKR) by interferon-stimulated gene 15 (ISG15) modification down-regulates protein translation. J Biol Chem 2012; 288:2839-47. [PMID: 23229543 DOI: 10.1074/jbc.m112.401851] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ubiquitin-like molecule ISG15 (UCRP) and protein modification by ISG15 (ISGylation) are strongly induced by interferon, genotoxic stress, and pathogen infection, suggesting that ISG15 plays an important role in innate immune responses. However, how ISGylation contributes to innate immune responses is not clear. The dsRNA-dependent protein kinase (PKR) inhibits translation by phosphorylating eIF2α to exert its anti-viral effect. ISG15 and PKR are induced by interferon, suggesting that a relationship exists between ISGylation and translational regulation. Here, we report that PKR is ISGylated at lysines 69 and 159. ISG15-modified PKR is active in the absence of virus infection and phosphorylates eIF2α to down-regulate protein translation. The present study describes a novel pathway for the activation of PKR and the regulation of protein translation.
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Affiliation(s)
- Fumihiko Okumura
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan.
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Maragno AL, Pironin M, Alcalde H, Cong X, Knobeloch KP, Tangy F, Zhang DE, Ghysdael J, Quang CT. ISG15 modulates development of the erythroid lineage. PLoS One 2011; 6:e26068. [PMID: 22022510 PMCID: PMC3192153 DOI: 10.1371/journal.pone.0026068] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 09/19/2011] [Indexed: 11/24/2022] Open
Abstract
Activation of erythropoietin receptor allows erythroblasts to generate erythrocytes. In a search for genes that are up-regulated during this differentiation process, we have identified ISG15 as being induced during late erythroid differentiation. ISG15 belongs to the ubiquitin-like protein family and is covalently linked to target proteins by the enzymes of the ISGylation machinery. Using both in vivo and in vitro differentiating erythroblasts, we show that expression of ISG15 as well as the ISGylation process related enzymes Ube1L, UbcM8 and Herc6 are induced during erythroid differentiation. Loss of ISG15 in mice results in decreased number of BFU-E/CFU-E in bone marrow, concomitant with an increased number of these cells in the spleen of these animals. ISG15(-/-) bone marrow and spleen-derived erythroblasts show a less differentiated phenotype both in vivo and in vitro, and over-expression of ISG15 in erythroblasts is found to facilitate erythroid differentiation. Furthermore, we have shown that important players of erythroid development, such as STAT5, Globin, PLC γ and ERK2 are ISGylated in erythroid cells. This establishes a new role for ISG15, besides its well-characterized anti-viral functions, during erythroid differentiation.
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Affiliation(s)
- Ana Leticia Maragno
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Martine Pironin
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Hélène Alcalde
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Xiuli Cong
- University of California San Diego, Moores University of California San Diego Cancer Center, La Jolla, California, United States of America
| | | | - Frederic Tangy
- Unité de Génomique Virale et Vaccination, CNRS URA-3015, Institut Pasteur, Paris, France
| | - Dong-Er Zhang
- University of California San Diego, Moores University of California San Diego Cancer Center, La Jolla, California, United States of America
| | - Jacques Ghysdael
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Christine Tran Quang
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
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Chen L, Li S, McGilvray I. The ISG15/USP18 ubiquitin-like pathway (ISGylation system) in hepatitis C virus infection and resistance to interferon therapy. Int J Biochem Cell Biol 2011; 43:1427-31. [PMID: 21704181 DOI: 10.1016/j.biocel.2011.06.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Accepted: 06/09/2011] [Indexed: 12/28/2022]
Abstract
The ISG15/USP18 pathway modulates cellular functions and is important for the host innate immune response to chronic viral infections such as Hepatitis C Virus (HCV). Interferon stimulated gene 15 (ISG15) was the first ubiquitin-like protein modifier identified. As in ubiquitination, ISG15 conjugates to target proteins (ISGylation) through the sequential enzymatic action of activating E1, conjugating E2, and ligating E3 enzymes. ISGylation modulates signal transduction pathways and host anti-viral response. The ISGylation process is reversible through the action of an ISG15 protease, USP18. Ubiquitin-like specific protease 18 (USP18) has functions that are both ISG15-dependent and ISG15-independent; the importance of the ISG15/USP18 pathway to chronic HCV infection is illustrated by the consistent finding of increased levels of ISG15 and USP18 in the liver tissue of patients who do not respond to interferon-based treatments. Mechanistically, HCV seems to exploit the ISG15/USP18 pathway to promote viral replication and evade innate anti-viral immune responses.
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Affiliation(s)
- Limin Chen
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences, Peking Union Medical College, Chengdu, Sichuan 610052, PR China.
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Wood LM, Sankar S, Reed RE, Haas AL, Liu LF, McKinnon P, Desai SD. A novel role for ATM in regulating proteasome-mediated protein degradation through suppression of the ISG15 conjugation pathway. PLoS One 2011; 6:e16422. [PMID: 21298066 PMCID: PMC3027683 DOI: 10.1371/journal.pone.0016422] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 12/15/2010] [Indexed: 01/12/2023] Open
Abstract
Ataxia Telangiectasia (A-T) is an inherited immunodeficiency disorder wherein mutation of the ATM kinase is responsible for the A-T pathogenesis. Although the precise role of ATM in A-T pathogenesis is still unclear, its function in responding to DNA damage has been well established. Here we demonstrate that in addition to its role in DNA repair, ATM also regulates proteasome-mediated protein turnover through suppression of the ISG15 pathway. This conclusion is based on three major pieces of evidence: First, we demonstrate that proteasome-mediated protein degradation is impaired in A-T cells. Second, we show that the reduced protein turnover is causally linked to the elevated expression of the ubiquitin-like protein ISG15 in A-T cells. Third, we show that expression of the ISG15 is elevated in A-T cells derived from various A-T patients, as well as in brain tissues derived from the ATM knockout mice and A-T patients, suggesting that ATM negatively regulates the ISG15 pathway. Our current findings suggest for the first time that proteasome-mediated protein degradation is impaired in A-T cells due to elevated expression of the ISG15 conjugation pathway, which could contribute to progressive neurodegeneration in A-T patients.
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Affiliation(s)
- Laurence M. Wood
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Surendran Sankar
- Department of Biochemistry and Molecular Biology, Louisiana State University of Health Sciences Center-School of Medicine, New Orleans, Louisiana, United States of America
| | - Ryan E. Reed
- Department of Biochemistry and Molecular Biology, Louisiana State University of Health Sciences Center-School of Medicine, New Orleans, Louisiana, United States of America
| | - Arthur L. Haas
- Department of Biochemistry and Molecular Biology, Louisiana State University of Health Sciences Center-School of Medicine, New Orleans, Louisiana, United States of America
| | - Leroy F. Liu
- Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey, United States of America
| | - Peter McKinnon
- Department of Genetics and Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Shyamal D. Desai
- Department of Biochemistry and Molecular Biology, Louisiana State University of Health Sciences Center-School of Medicine, New Orleans, Louisiana, United States of America
- * E-mail:
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Zhang D, Zhang DE. Interferon-stimulated gene 15 and the protein ISGylation system. J Interferon Cytokine Res 2010; 31:119-30. [PMID: 21190487 DOI: 10.1089/jir.2010.0110] [Citation(s) in RCA: 246] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Interferon-stimulated gene 15 (ISG15) is one of the most upregulated genes upon Type I interferon treatment or pathogen infection. Its 17 kDa protein product, ISG15, was the first ubiquitin-like modifier identified, and is similar to a ubiquitin linear dimer. As ISG15 modifies proteins in a similar manner to ubiquitylation, protein conjugation by ISG15 is termed ISGylation. Some of the primary enzymes that promote ISGylation are also involved in ubiquitin conjugation. The process to remove ISG15 from its conjugated proteins, termed de-ISGylation, is performed by a cellular ISG15-specific protease, ubiquitin-specific proteases with molecular mass 43 kDa (UBP43)/ubiquitin-specific proteases 18. Relative to ubiquitin, the biological function of ISG15 is still poorly understood, but ISG15 appears to play important roles in various biological and cellular functions. Therefore, there is growing interest in ISG15, as the study of free ISG15 and functional consequences of ISGylation/de-ISGylation may identify useful therapeutic targets. This review highlights recent discoveries and remaining questions important to understanding the biological functions of ISG15.
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Affiliation(s)
- Dongxian Zhang
- Sanford-Burnham Medical Research Institute, La Jolla, California, USA
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Antiviral Properties of ISG15. Viruses 2010; 2:2154-2168. [PMID: 21994614 PMCID: PMC3185569 DOI: 10.3390/v2102154] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 09/08/2010] [Accepted: 09/15/2010] [Indexed: 12/04/2022] Open
Abstract
The type I interferon system plays a critical role in limiting the spread of viral infection. Viruses induce the production of interferon (IFN), which after binding to the IFN-α/β receptor (IFNAR), and triggering of the JAK/STAT signaling cascade, results in the induction of interferon-stimulated genes (ISGs). These ISGs function to inhibit viral replication and to regulate the host immune response. Among these ISGs, the ubiquitin-like molecule, ISG15, is one of the most strongly induced proteins. Similar to ubiquitin, through an IFN induced conjugation cascade, ISG15 is covalently linked to a variety of cellular proteins, suggesting regulation of different cellular processes. Studies performed over the past several years have shown that ISG15 plays a central role in the host’s antiviral response against many viruses. Mice lacking ISG15 display increased susceptibility to multiple viruses. Furthermore, several viruses have developed immune evasion strategies that directly target the ISG15 pathway. Work is now underway to determine the mechanism by which ISG15 functions as an antiviral molecule, such that therapies targeting this pathway can be developed in the future.
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Abstract
The host innate immune response, including the production of type-I IFN, represents the primary line of defense against invading viral pathogens. Of the hundreds of IFN-stimulated genes (ISGs) discovered to date, ISG15 was one of the first identified and shown to encode a ubiquitin-like protein that functions, in part, as a modifier of protein function. Evidence implicating ISG15 as an innate immune protein with broad-spectrum antiviral activity continues to accumulate rapidly. This review will summarize recent findings on the innate antiviral activity of ISG15, with a focus on the interplay between ubiquitination and ISGylation pathways resulting in modulation of RNA virus assembly/budding. Indeed, ubiquitination is known to be proviral for some RNA viruses, whereas the parallel ISGylation pathway is known to be antiviral. A better understanding of the antiviral activities of ISG15 will enhance our fundamental knowledge of host innate responses to viral pathogens and may provide insight useful for the development of novel therapeutic approaches designed to enhance the immune response against such pathogens.
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Affiliation(s)
- Ronald N Harty
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Jeon YJ, Yoo HM, Chung CH. ISG15 and immune diseases. Biochim Biophys Acta Mol Basis Dis 2010; 1802:485-96. [PMID: 20153823 PMCID: PMC7127291 DOI: 10.1016/j.bbadis.2010.02.006] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 02/08/2010] [Accepted: 02/09/2010] [Indexed: 12/22/2022]
Abstract
ISG15, the product of interferon (IFN)-stimulated gene 15, is the first identified ubiquitin-like protein, consisting of two ubiquitin-like domains. ISG15 is synthesized as a precursor in certain mammals and, therefore, needs to be processed to expose the C-terminal glycine residue before conjugation to target proteins. A set of three-step cascade enzymes, an E1 enzyme (UBE1L), an E2 enzyme (UbcH8), and one of several E3 ligases (e.g., EFP and HERC5), catalyzes ISG15 conjugation (ISGylation) of a specific protein. These enzymes are unique among the cascade enzymes for ubiquitin and other ubiquitin-like proteins in that all of them are induced by type I IFNs or other stimuli, such as exposure to viruses and lipopolysaccharide. Mass spectrometric analysis has led to the identification of several hundreds of candidate proteins that can be conjugated by ISG15. Some of them are type I IFN-induced proteins, such as PKR and RIG-I, and some are the key regulators that are involved in IFN signaling, such as JAK1 and STAT1, implicating the role of ISG15 and its conjugates in type I IFN-mediated innate immune responses. However, relatively little is known about the functional significance of ISG15 induction due to the lack of information on the consequences of its conjugation to target proteins. Here, we describe the recent progress made in exploring the biological function of ISG15 and its reversible modification of target proteins and thus in their implication in immune diseases.
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Affiliation(s)
| | | | - Chin Ha Chung
- School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea
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Abstract
This chapter recapitulates our current knowledge about the functions of the interferon stimulated gene 15 (ISG15) system in vivo with a specific focus on physiological aspects and the biological relevance of ISG15 conjugation and deconjugation. ISG15 contains two domains with structural similarity to ubiquitin and was the first ubiquitin like modifier (UBL) described. It can be conjugated to protein substrates in a process similar to ubiquitin modification termed ISGylation. Of all ubiquitin like modifications ISGylation exhibits the highest degree of interlace with the ubiquitin system and distinct ubiquitin ligases and isopeptidases can also mediate ISG15 linkage and deconjugation, respectively. The system is strongly induced by Type I interferons or microbial infections and studies based on gene targeted mice have shown that it plays an important role in antiviral defence.
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Affiliation(s)
- Klaus-Peter Knobeloch
- Department of Neuropathology, University Freiburg, Breisacher Str.64, 79106, Freiburg, Germany,
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van Wijk SJL, Timmers HTM. The family of ubiquitin-conjugating enzymes (E2s): deciding between life and death of proteins. FASEB J 2009; 24:981-93. [PMID: 19940261 DOI: 10.1096/fj.09-136259] [Citation(s) in RCA: 283] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The family of ubiquitin-conjugating (E2) enzymes is characterized by the presence of a highly conserved ubiquitin-conjugating (UBC) domain. These domains accommodate the ATP-activated ubiquitin (Ub) or ubiquitin-like (UBL) protein via a covalently linked thioester onto its active-site residue. E2 enzymes act via selective protein-protein interactions with the E1 and E3 enzymes and connect activation to covalent modification. By doing so, E2s differentiate effects on downstream substrates, either with a single Ub/UBL molecule or as a chain. While E3s are involved in substrate selection, E2s are the main determinants for selection of the lysine to construct ubiquitin chains, which thereby directly control the cellular fate of the substrate. In humans, 35 active E2 enzymes have been identified so far, while other eukaryotic genomes harbor 16 to 35 E2 family members. Some E2s possess N- and/or C-terminal extensions that mediate E2-specific processes. During the past two decades, strong support has led to the control of E2 enzymes in decisions concerning the life or death of a protein. Here, we summarize current knowledge and recent developments on E2 enzymes with respect to structural characteristics and functions. From this we propose a shell-like model to rationalize the selectivity of these key enzymes in directing Ub/UBL-conjugation pathways.-Van Wijk, S. J. L., Timmers, H. T. M. The family of ubiquitin-conjugating enzymes (E2s): deciding between life and death of proteins.
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Affiliation(s)
- Sjoerd J L van Wijk
- Department of Physiological Chemistry, Division of Biomedical Genetics, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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Abstract
The androgen receptor (AR) plays a crucial role in the modulation of prostate cell proliferation and is involved in the development and progression of prostate cancer (PCa). An understanding of the complex regulation of AR provides novel treatment options for PCa. Here, we show (i) that the ubiquitin-like modifier, interferon-stimulated gene 15 (ISG15), and most enzymes involved in ISG15 conjugation were upregulated in tumor samples versus in non-malignant tissues of PCa patients and (ii) that the expression of these components significantly differed between tumors in patients treated with and without androgen ablation. Using PCa cell lines as in vitro models, the specific androgen-mediated, AR-dependent regulation of the ISGylation components was confirmed. In addition, the ISGylation system controls AR mRNA and protein expressions, as overexpression of Ube1L as a limiting ISGylation factor in the AR(+) androgen-sensitive PCa cell line, LNCaP, results in significant AR upregulation, accompanied by an increased proliferation even under androgen deprivation. Accordingly, Ube1L knockdown decreased the AR expression. Thus, this study describes for the first time the modulation of AR expression by ISGylation components, which affects the proliferation of PCa cells, thereby providing evidence for a novel function of the ISGylation system in malignant transformation.
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Minakawa M, Sone T, Takeuchi T, Yokosawa H. Regulation of the nuclear factor (NF)-kappaB pathway by ISGylation. Biol Pharm Bull 2009; 31:2223-7. [PMID: 19043203 DOI: 10.1248/bpb.31.2223] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Post-translational modification with ISG15 (interferon-stimulated gene 15 kDa) (ISGylation) is mediated by a sequential reaction similar to ubiquitination, and various target proteins for ISGylation have been identified. We previously reported that ISGylation of the E2 ubiquitin-conjugating enzyme Ubc13 suppresses its E2 activity. Ubc13 forms a heterodimer with Uev1A, a ubiquitin-conjugating enzyme variant, and the Ubc13-Uev1A complex catalyzes the assembly of a Lys63-linked polyubiquitin chain, which plays a non-proteolytic role in the nuclear factor (NF)-kappaB pathway. In this study, we examined the effect of ISGylation on tumor necrosis factor receptor-associated factor (TRAF)-6/transforming growth factor beta-activated kinase (TAK)-1-dependent NF-kappaB activation. We found that expression of the ISGylation system suppresses NF-kappaB activation via TRAF6 and TAK1 and that the level of polyubiquitinated TRAF6 is reduced by expression of the ISGylation system. Taken together, the results suggest that the NF-kappaB pathway is negatively regulated by ISGylation.
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Affiliation(s)
- Miki Minakawa
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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Ruosaari S, Hienonen-Kempas T, Puustinen A, Sarhadi VK, Hollmén J, Knuutila S, Saharinen J, Wikman H, Anttila S. Pathways affected by asbestos exposure in normal and tumour tissue of lung cancer patients. BMC Med Genomics 2008; 1:55. [PMID: 19014429 PMCID: PMC2612681 DOI: 10.1186/1755-8794-1-55] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 11/11/2008] [Indexed: 12/03/2022] Open
Abstract
Background Studies on asbestos-induced tumourigenesis have indicated the role of, e.g., reactive oxygen/nitrogen species, mitochondria, as well as NF-κB and MAPK signalling pathways. The exact molecular mechanisms contributing to asbestos-mediated carcinogenesis are, however, still to be characterized. Methods In this study, gene expression data analyses together with gene annotation data from the Gene Ontology (GO) database were utilized to identify pathways that are differentially regulated in lung and tumour tissues between asbestos-exposed and non-exposed lung cancer patients. Differentially regulated pathways were identified from gene expression data from 14 asbestos-exposed and 14 non-exposed lung cancer patients using custom-made software and Iterative Group Analysis (iGA). Western blotting was used to further characterize the findings, specifically to determine the protein levels of UBA1 and UBA7. Results Differences between asbestos-related and non-related lung tumours were detected in pathways associated with, e.g., ion transport, NF-κB signalling, DNA repair, as well as spliceosome and nucleosome complexes. A notable fraction of the pathways down-regulated in both normal and tumour tissue of the asbestos-exposed patients were related to protein ubiquitination, a versatile process regulating, for instance, DNA repair, cell cycle, and apoptosis, and thus being also a significant contributor of carcinogenesis. Even though UBA1 or UBA7, the early enzymes involved in protein ubiquitination and ubiquitin-like regulation of target proteins, did not underlie the exposure-related deregulation of ubiquitination, a difference was detected in the UBA1 and UBA7 levels between squamous cell carcinomas and respective normal lung tissue (p = 0.02 and p = 0.01) without regard to exposure status. Conclusion Our results indicate alterations in protein ubiquitination related both to cancer type and asbestos. We present for the first time pathway analysis results on asbestos-associated lung cancer, providing important insight into the most relevant targets for future research.
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Affiliation(s)
- Salla Ruosaari
- Biological Mechanisms and Prevention of Work-related Diseases, Health and Work Ability, Finnish Institute of Occupational Health, Topeliuksenkatu 41aA, FI-00250 Helsinki, Finland.
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Okumura F, Lenschow DJ, Zhang DE. Nitrosylation of ISG15 prevents the disulfide bond-mediated dimerization of ISG15 and contributes to effective ISGylation. J Biol Chem 2008; 283:24484-8. [PMID: 18606809 DOI: 10.1074/jbc.m803795200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The expression of the ubiquitin-like molecule ISG15 (UCRP) and protein modification by ISG15 (ISGylation) are strongly activated by interferon, genotoxic stress, and pathogen infection, suggesting that ISG15 plays an important role in innate immune responses. Inducible nitric-oxide synthase (iNOS) is induced by the similar stimuli as ISG15 and enhances the production of nitric oxide (NO), a pleiotropic free radical with antipathogen activity. Here, we report that cysteine residues (Cys-76 and -143 in mouse, Cys-78 in human) of ISG15 can be modified by NO, and the NO modification of ISG15 decreases the dimerization of ISG15. The mutation of the cysteine residue of ISG15 to serine improves total ISGylation. The NO synthase inhibitor S-ethylisothiourea reduces endogenous ISGylation. Furthermore, ectopic expression of iNOS enhanced total ISGylation. Together, these results suggest that nitrosylation of ISG15 enhances target protein ISGylation. This is the first report of a relationship between ISGylation and nitrosylation.
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Affiliation(s)
- Fumihiko Okumura
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
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Abstract
Since the discovery of interferons (IFNs), considerable progress has been made in describing the nature of the cytokines themselves, the signalling components that direct the cell response and their antiviral activities. Gene targeting studies have distinguished four main effector pathways of the IFN-mediated antiviral response: the Mx GTPase pathway, the 2',5'-oligoadenylate-synthetase-directed ribonuclease L pathway, the protein kinase R pathway and the ISG15 ubiquitin-like pathway. As discussed in this Review, these effector pathways individually block viral transcription, degrade viral RNA, inhibit translation and modify protein function to control all steps of viral replication. Ongoing research continues to expose additional activities for these effector proteins and has revealed unanticipated functions of the antiviral response.
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Affiliation(s)
- Anthony J. Sadler
- Monash Institute of Medical Research, Monash University, Clayton, 3168 Victoria Australia
| | - Bryan R. G. Williams
- Monash Institute of Medical Research, Monash University, Clayton, 3168 Victoria Australia
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Abstract
Background ISG15 is an Ubiquitin-like protein, highly induced by Type I Interferons. Upon the cooperative activity of specific Ubiquitinating enzymes, ISG15 can be conjugated to its substrates. Increasing evidence points to a role for protein ISGylation in anti-viral and anti-tumoral defense. Principal Findings We identified ISG15 from Old World Monkeys (OWm) as a hyper-efficient protein modifier. Western blot analysis visualized more efficient conjugation of OWmISG15 relative to HuISG15 in human (Hu), monkey and mouse (Mo) cell-lines. Moreover, the substrates of OWmISG15 identified upon Tandem Affinity Purification followed by LC-MS/MS identification largely outnumbered these of HuISG15 itself. Several Ubiquitin-Conjugating enzymes were identified as novel ISGylated substrates. Introduction of a N89D mutation in HuISG15 improved its ISGylation capacity, and additional Q31K/T33A/D133N mutations yielded a HuISG15 variant with an ISGylation efficiency comparable to OWmISG15. Homology modeling and structural superposition situate N89 in the interaction interface with the Activating enzyme. Analysis of the UbE1L residues in this interface revealed a striking homology between OWmUbE1L and HuUbE1, the Activating enzyme of Ubiquitin. In line with this observation, we found efficient activation of AgmISG15, but not HuISG15 or MoISG15, by HuUbE1, thus providing a likely explanation for OWm hyperISGylation. Conclusions This study discloses the poor conjugation competence of HuISG15 compared to OWmISG15 and maps the critical determinants for efficient conjugation. HyperISGylation may greatly assist ISGylation studies and may enhance its function as positive regulator of Interferon-related immune responses or as anti-tumoral modulator.
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Abstract
ISG15 is a ubiquitin-like modifi er that is conjugated to target proteins by a sequential reaction catalyzed by E1/E2/E3 enzymes (protein ISGylation). ISG15 and protein ISGylation are upregulated by interferon stimuli. ISG15 functions as an antiviral protein against Sindbis virus and HIV-1, but the molecular mechanism remains unknown. Here we describe in detail methods for detecting and analyzing protein ISGylation. The methods consist of plasmid transfection and affi nity purifi cation of ISGylated proteins. In addition, we describe a method for detecting ISGylation of a target protein, Ubc13.
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Arimoto KI, Konishi H, Shimotohno K. UbcH8 regulates ubiquitin and ISG15 conjugation to RIG-I. Mol Immunol 2008; 45:1078-84. [PMID: 17719635 DOI: 10.1016/j.molimm.2007.07.021] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2007] [Accepted: 07/20/2007] [Indexed: 12/27/2022]
Abstract
The RNA helicase retinoic inducible gene I (RIG-I) recognizes viral double-stranded RNA and initiates signaling cascades that lead to activation of the protein kinases IKKalphabeta, TBK1 and IKKepsilon, and to subsequent activation of the transcription factors NF-kappaB and IRF3. We recently reported that RIG-I was ubiquitinated by RNF125, an ubiquitin E3 ligase, leading to proteasomal degradation. RIG-I is also reported to be ISGylated by an unidentified ISG15 (IFN-stimulated gene, 15kDa) E3 ligase. UbcH8, an ubiquitin E2 conjugating enzyme, was shown to be involved in RIG-I ISGylation. Here, we found that UbcH8 suppressed RIG-I ubiquitination by RNF125, and this suppression was relieved by ectopic expression of ISG15. Alternately, ISG15 conjugation to RIG-I was suppressed by RNF125. By analyzing this regulatory circuit, we found that UbcH8 and ISG15 are functional regulators of RNF125 E3 ligase activity, which regulates the level of ubiquitin and ISG15 conjugation of RIG-I.
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Affiliation(s)
- Kei-Ichiro Arimoto
- Institute for Virus Research, Kyoto University, Shogo-in, Sakyo-ku, Kyoto 606-8507, Japan
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40
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Okumura F, Zou W, Zhang DE. ISG15 modification of the eIF4E cognate 4EHP enhances cap structure-binding activity of 4EHP. Genes Dev 2007; 21:255-60. [PMID: 17289916 PMCID: PMC1785121 DOI: 10.1101/gad.1521607] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The expression of the ubiquitin-like molecule ISG15 and protein modification by ISG15 (ISGylation) are strongly activated by interferon, genotoxic stress, and pathogen infection, suggesting that ISG15 plays an important role in innate immune responses. 4EHP is an mRNA 5' cap structure-binding protein and acts as a translation suppressor by competing with eIF4E for binding to the cap structure. Here, we report that 4EHP is modified by ISG15 and ISGylated 4EHP has a much higher cap structure-binding activity. These data suggest that ISGylation of 4EHP may play an important role in cap structure-dependent translation control in immune responses.
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Affiliation(s)
- Fumihiko Okumura
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Weiguo Zou
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Dong-Er Zhang
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- Corresponding author.E-MAIL ; FAX (858) 784-9593
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41
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Zou W, Wang J, Zhang DE. Negative regulation of ISG15 E3 ligase EFP through its autoISGylation. Biochem Biophys Res Commun 2007; 354:321-7. [PMID: 17222803 PMCID: PMC1858649 DOI: 10.1016/j.bbrc.2006.12.210] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 12/30/2006] [Indexed: 12/27/2022]
Abstract
The function of ubiquitin-like protein ISG15 and protein modification by ISG15 (ISGylation) has been an enigma for many years. Recently, the research of ISGylation has been accelerated by the identification of the enzymes involved in the ISG15 conjugation process. Our previous study identified the interferon inducible protein EFP as an ISG15 isopeptide ligase (E3) for 14-3-3sigma. In this study, we show that ISG15 E3 ligase EFP can be modified by ISG15. Two ubiquitin E2 conjugating enzymes, UbcH6 and UbcH8, can support ISGylation of EFP. The Ring-finger domain of EFP is important for its ISGylation. Full-length EFP can enhance the ISGylation of Ring domain deleted EFP, indicating EFP can function as an ISG15 E3 ligase for itself. We also determined the ISGylation site of EFP and created its ISGylation resistant mutant EFP-K117R. Compared to the wild-type EFP, this mutant further increases the ISGylation of 14-3-3sigma. Thus we propose that autoISGylation of EFP negatively regulates its ISG15 E3 ligase activity for 14-3-3sigma.
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Affiliation(s)
- Weiguo Zou
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Nakasato N, Ikeda K, Urano T, Horie-Inoue K, Takeda S, Inoue S. A ubiquitin E3 ligase Efp is up-regulated by interferons and conjugated with ISG15. Biochem Biophys Res Commun 2006; 351:540-6. [PMID: 17069755 DOI: 10.1016/j.bbrc.2006.10.061] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Accepted: 10/12/2006] [Indexed: 11/28/2022]
Abstract
Interferon (IFN) regulates various target genes that mediate important roles in immune responses such as antiviral state. Protein ISG15-conjugation (ISGylation) is implicated in the IFN-induced antiviral response. Here we demonstrate that Efp mRNA as well as protein expression could be up-regulated by Type I IFN in HeLa cells and HepG2 cells. Luciferase assay reveals that the first intron of Efp gene contains a functional interferon-stimulated response element (ISRE) and electrophoretic mobility shift assay shows that the ISRE binds to signal transducer and activator of transcription 1 (STAT1). Chromatin immunoprecipitation assays have shown that the ISRE recruits STAT1 in vivo IFN-dependently. Moreover, we demonstrate that Efp protein could be conjugated with not only ubiquitin but also ISG15. These data suggest that Efp is an IFN-responsive gene that potentially mediates IFN actions, involved in ISGylation and ubiquitination of proteins including Efp itself.
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Affiliation(s)
- Norie Nakasato
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama, Japan
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Takeuchi T, Inoue S, Yokosawa H. Identification and Herc5-mediated ISGylation of novel target proteins. Biochem Biophys Res Commun 2006; 348:473-7. [PMID: 16884686 DOI: 10.1016/j.bbrc.2006.07.076] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Accepted: 07/15/2006] [Indexed: 12/28/2022]
Abstract
ISG15, a protein containing two ubiquitin-like domains, is an interferon-stimulated gene product that functions in antiviral response and is conjugated to various cellular proteins (ISGylation) upon interferon stimulation. ISGylation occurs via a pathway similar to the pathway for ubiquitination that requires the sequential action of E1/E2/E3: the E1 (UBE1L), E2 (UbcH8), and E3 (Efp/Herc5) enzymes for ISGylation have been hitherto identified. In this study, we identified six novel candidate target proteins for ISGylation by a proteomic approach. Four candidate target proteins were demonstrated to be ISGylated in UBE1L- and UbcH8-dependent manners, and ISGylation of the respective target proteins was stimulated by Herc5. In addition, Herc5 was capable of binding with the respective target proteins. Thus, these results suggest that Herc5 functions as a general E3 ligase for protein ISGylation.
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Affiliation(s)
- Tomoharu Takeuchi
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
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Takeuchi T, Kobayashi T, Tamura S, Yokosawa H. Negative regulation of protein phosphatase 2Cbeta by ISG15 conjugation. FEBS Lett 2006; 580:4521-6. [PMID: 16872604 DOI: 10.1016/j.febslet.2006.07.032] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 07/05/2006] [Accepted: 07/10/2006] [Indexed: 12/22/2022]
Abstract
ISG15, an interferon-upregulated ubiquitin-like protein, is covalently conjugated to various cellular proteins (ISGylation). In this study, we found that protein phosphatase 2Cbeta (PP2Cbeta), which functions in the nuclear factor kappaB (NF-kappaB) pathway via dephosphorylation of TGF-beta-activated kinase, was ISGylated, and analysis by NF-kappaB luciferase reporter assay revealed that PP2Cbeta activity was suppressed by co-expression of ISG15, UBE1L, and UbcH8. We determined the ISGylation sites of PP2Cbeta and constructed its ISGylation-resistant mutant. In contrast to the wild type, this mutant suppressed the NF-kappaB pathway even in the presence of ISG15, UBE1L, and UbcH8. Thus, we propose that ISGylation negatively regulates PP2Cbeta activity.
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Affiliation(s)
- Tomoharu Takeuchi
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
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