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Sato K, Nakamura T, Morimatsu M, Agui T. Functional Analysis of Oligoadenylate Synthetase in the Emu ( Dromaius novaehollandiae). Animals (Basel) 2024; 14:1579. [PMID: 38891626 PMCID: PMC11171313 DOI: 10.3390/ani14111579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 05/24/2024] [Accepted: 05/25/2024] [Indexed: 06/21/2024] Open
Abstract
2'-5'-oligoadenylate synthetase (OAS) is one of the proteins that act as a defense mechanism against foreign RNA in cells. OAS has two functions: an antiviral effect against a wide range of virus species via the OAS/RNase L pathway with synthesized oligoadenylates and inhibition of viral replication specific to viruses of the genus Flavivirus, which is independent of enzymatic activity. Several birds have been reported to possess only one type of OAS family member, OASL, which has both enzymatic activity and inhibitory effects on flaviviral replication. However, the ostrich has two types of OASs, OAS1 and OASL, which show different functions-enzymatic and anti-flaviviral activities, respectively. In this study, emu OASs were cloned to investigate their sequence and function and elucidate the role of OASs in emus. The cloning results showed that emus had OAS1 and OASL, suggesting that emu OASs were more closely related to ostrich than to other birds. Functional investigations showed that emu OAS1 and OASL had enzymatic and anti-flaviviral activities, respectively, similar to those of the ostrich. Emus and ostriches are evolutionarily different from most birds and may be more closely related to mammalian OAS diversity.
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Affiliation(s)
- Keisuke Sato
- Laboratory of Laboratory Animal Science and Medicine, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan; (T.N.); (M.M.); (T.A.)
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Harioudh MK, Perez J, Chong Z, Nair S, So L, McCormick KD, Ghosh A, Shao L, Srivastava R, Soveg F, Ebert TS, Atianand MK, Hornung V, Savan R, Diamond MS, Sarkar SN. Oligoadenylate synthetase 1 displays dual antiviral mechanisms in driving translational shutdown and protecting interferon production. Immunity 2024; 57:446-461.e7. [PMID: 38423012 PMCID: PMC10939734 DOI: 10.1016/j.immuni.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 11/15/2023] [Accepted: 02/05/2024] [Indexed: 03/02/2024]
Abstract
In response to viral infection, how cells balance translational shutdown to limit viral replication and the induction of antiviral components like interferons (IFNs) is not well understood. Moreover, how distinct isoforms of IFN-induced oligoadenylate synthetase 1 (OAS1) contribute to this antiviral response also requires further elucidation. Here, we show that human, but not mouse, OAS1 inhibits SARS-CoV-2 replication through its canonical enzyme activity via RNase L. In contrast, both mouse and human OAS1 protect against West Nile virus infection by a mechanism distinct from canonical RNase L activation. OAS1 binds AU-rich elements (AREs) of specific mRNAs, including IFNβ. This binding leads to the sequestration of IFNβ mRNA to the endomembrane regions, resulting in prolonged half-life and continued translation. Thus, OAS1 is an ARE-binding protein with two mechanisms of antiviral activity: driving inhibition of translation but also a broader, non-canonical function of protecting IFN expression from translational shutdown.
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Affiliation(s)
- Munesh K Harioudh
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Joseph Perez
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Zhenlu Chong
- Departments of Medicine, Molecular Microbiology, Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Sharmila Nair
- Departments of Medicine, Molecular Microbiology, Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Lomon So
- Department of Immunology, School of Medicine, University of Washington, Seattle, WA, USA; Division of Immunology, Benaroya Research Institute, Seattle, WA, USA
| | - Kevin D McCormick
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Arundhati Ghosh
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Lulu Shao
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Rashmi Srivastava
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA
| | - Frank Soveg
- Department of Immunology, School of Medicine, University of Washington, Seattle, WA, USA
| | - Thomas S Ebert
- Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Maninjay K Atianand
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Veit Hornung
- Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Ram Savan
- Department of Immunology, School of Medicine, University of Washington, Seattle, WA, USA
| | - Michael S Diamond
- Departments of Medicine, Molecular Microbiology, Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Saumendra N Sarkar
- Cancer Virology Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Microbiology and Molecular Genetics, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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Sarkar SN, Harioudh MK, Shao L, Perez J, Ghosh A. The Many Faces of Oligoadenylate Synthetases. J Interferon Cytokine Res 2023; 43:487-494. [PMID: 37751211 PMCID: PMC10654648 DOI: 10.1089/jir.2023.0098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 08/13/2023] [Indexed: 09/27/2023] Open
Abstract
2'-5' Oligoadenylate synthetases (OAS) are interferon-stimulated genes that are most well-known to protect hosts from viral infections. They are evolutionarily related to an ancient family of Nucleotidyltransferases, which are primarily involved in pathogen-sensing and innate immune response. Classical function of OAS proteins involves double-stranded RNA-stimulated polymerization of adenosine triphosphate in 2'-5' oligoadenylates (2-5A), which can activate the latent RNase (RNase L) to degrade RNA. However, accumulated evidence over the years have suggested alternative mode of antiviral function of several OAS family proteins. Furthermore, recent studies have connected some OAS proteins with wider function beyond viral infection. Here, we review some of the canonical and noncanonical functions of OAS proteins and their mechanisms.
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Affiliation(s)
- Saumendra N. Sarkar
- Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Munesh K. Harioudh
- Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Lulu Shao
- Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Joseph Perez
- Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Arundhati Ghosh
- Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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4
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Wang X, Hu J, Song L, Rong E, Yang C, Chen X, Pu J, Sun H, Gao C, Burt DW, Liu J, Li N, Huang Y. Functional divergence of oligoadenylate synthetase 1 (OAS1) proteins in Tetrapods. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1395-1412. [PMID: 34826092 DOI: 10.1007/s11427-021-2002-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
OASs play critical roles in immune response against virus infection by polymerizing ATP into 2-5As, which initiate the classical OAS/RNase L pathway and induce degradation of viral RNA. OAS members are functionally diverged in four known innate immune pathways (OAS/RNase L, OASL/IRF7, OASL/RIG-I, and OASL/cGAS), but how they functionally diverged is unclear. Here, we focus on evolutionary patterns and explore the link between evolutionary processes and functional divergence of Tetrapod OAS1. We show that Palaeognathae and Primate OAS1 genes are conserved in genomic and protein structures but differ in function. The former (i.e., ostrich) efficiently synthesized long 2-5A and activated RNase L, while the latter (i.e., human) synthesized short 2-5A and did not activate RNase L. We predicted and verified that two in-frame indels and one positively selected site in the active site pocket contributed to the functional divergence of Palaeognathae and Primate OAS1. Moreover, we discovered and validated that an in-frame indel in the C-terminus of Palaeognathae OAS1 affected the binding affinity of dsRNA and enzymatic activity, and contributed to the functional divergence of Palaeognathae OAS1 proteins. Our findings unravel the molecular mechanism for functional divergence and give insights into the emergence of novel functions in Tetrapod OAS1.
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Affiliation(s)
- Xiaoxue Wang
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - Jiaxiang Hu
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - Linfei Song
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - Enguang Rong
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - Chenghuai Yang
- China Institute of Veterinary Drug Control, Beijing, 100081, China
| | - Xiaoyun Chen
- China Institute of Veterinary Drug Control, Beijing, 100081, China
| | - Juan Pu
- Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100083, China
| | - Honglei Sun
- Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100083, China
| | - Chuze Gao
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - David W Burt
- University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Jinhua Liu
- Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100083, China
| | - Ning Li
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China
| | - Yinhua Huang
- State Key Laboratory for Agrobiotechnology, College of Biology Sciences, China Agricultural University, Beijing, 100193, China.
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5
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Blahove MR, Carter JR. Flavivirus Persistence in Wildlife Populations. Viruses 2021; 13:v13102099. [PMID: 34696529 PMCID: PMC8541186 DOI: 10.3390/v13102099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/01/2021] [Accepted: 10/08/2021] [Indexed: 12/14/2022] Open
Abstract
A substantial number of humans are at risk for infection by vector-borne flaviviruses, resulting in considerable morbidity and mortality worldwide. These viruses also infect wildlife at a considerable rate, persistently cycling between ticks/mosquitoes and small mammals and reptiles and non-human primates and humans. Substantially increasing evidence of viral persistence in wildlife continues to be reported. In addition to in humans, viral persistence has been shown to establish in mammalian, reptile, arachnid, and mosquito systems, as well as insect cell lines. Although a considerable amount of research has centered on the potential roles of defective virus particles, autophagy and/or apoptosis-induced evasion of the immune response, and the precise mechanism of these features in flavivirus persistence have yet to be elucidated. In this review, we present findings that aid in understanding how vector-borne flavivirus persistence is established in wildlife. Research studies to be discussed include determining the critical roles universal flavivirus non-structural proteins played in flaviviral persistence, the advancement of animal models of viral persistence, and studying host factors that allow vector-borne flavivirus replication without destructive effects on infected cells. These findings underscore the viral–host relationships in wildlife animals and could be used to elucidate the underlying mechanisms responsible for the establishment of viral persistence in these animals.
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6
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Soveg FW, Schwerk J, Gokhale NS, Cerosaletti K, Smith JR, Pairo-Castineira E, Kell AM, Forero A, Zaver SA, Esser-Nobis K, Roby JA, Hsiang TY, Ozarkar S, Clingan JM, McAnarney ET, Stone AEL, Malhotra U, Speake C, Perez J, Balu C, Allenspach EJ, Hyde JL, Menachery VD, Sarkar SN, Woodward JJ, Stetson DB, Baillie JK, Buckner JH, Gale M, Savan R. Endomembrane targeting of human OAS1 p46 augments antiviral activity. eLife 2021; 10:e71047. [PMID: 34342578 PMCID: PMC8357416 DOI: 10.7554/elife.71047] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 06/11/2021] [Indexed: 12/14/2022] Open
Abstract
Many host RNA sensors are positioned in the cytosol to detect viral RNA during infection. However, most positive-strand RNA viruses replicate within a modified organelle co-opted from intracellular membranes of the endomembrane system, which shields viral products from cellular innate immune sensors. Targeting innate RNA sensors to the endomembrane system may enhance their ability to sense RNA generated by viruses that use these compartments for replication. Here, we reveal that an isoform of oligoadenylate synthetase 1, OAS1 p46, is prenylated and targeted to the endomembrane system. Membrane localization of OAS1 p46 confers enhanced access to viral replication sites and results in increased antiviral activity against a subset of RNA viruses including flaviviruses, picornaviruses, and SARS-CoV-2. Finally, our human genetic analysis shows that the OAS1 splice-site SNP responsible for production of the OAS1 p46 isoform correlates with protection from severe COVID-19. This study highlights the importance of endomembrane targeting for the antiviral specificity of OAS1 and suggests that early control of SARS-CoV-2 replication through OAS1 p46 is an important determinant of COVID-19 severity.
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Affiliation(s)
- Frank W Soveg
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Johannes Schwerk
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Nandan S Gokhale
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | | | - Julian R Smith
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | | | - Alison M Kell
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
- Department of Molecular Genetics and Microbiology, School of Medicine, University of New MexicoAlbuquerqueUnited States
| | - Adriana Forero
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - Shivam A Zaver
- Department of Microbiology, School of Medicine, University of WashingtonSeattleUnited States
| | - Katharina Esser-Nobis
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Justin A Roby
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Tien-Ying Hsiang
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Snehal Ozarkar
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Jonathan M Clingan
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Eileen T McAnarney
- Department of Microbiology and Immunology, University of Texas Medical CenterGalvestonUnited States
| | - Amy EL Stone
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
- Department of Basic Sciences, College of Osteopathic Medicine, Touro University NevadaHendersonUnited States
| | - Uma Malhotra
- Department of Infectious Disease, Virginia Mason Medical CenterSeattleUnited States
- Department of Medicine, Section of Infectious Diseases, University of WashingtonSeattleUnited States
| | - Cate Speake
- Benaroya Research Institute at Virginia MasonSeattleUnited States
| | - Joseph Perez
- Cancer Virology Program, University of Pittsburgh Cancer Institute, University of PittsburghPittsburghUnited States
| | - Chiraag Balu
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Eric J Allenspach
- Center for Immunity and Immunotherapies, Seattle Children's Research InstituteSeattleUnited States
| | - Jennifer L Hyde
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - Vineet D Menachery
- Department of Microbiology and Immunology, University of Texas Medical CenterGalvestonUnited States
| | - Saumendra N Sarkar
- Cancer Virology Program, University of Pittsburgh Cancer Institute, University of PittsburghPittsburghUnited States
| | - Joshua J Woodward
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
- Department of Microbiology, School of Medicine, University of WashingtonSeattleUnited States
| | - Daniel B Stetson
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - John Kenneth Baillie
- Roslin Institute, University of EdinburghEdinburghUnited Kingdom
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General HospitalEdinburghUnited Kingdom
| | - Jane H Buckner
- Benaroya Research Institute at Virginia MasonSeattleUnited States
| | - Michael Gale
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
| | - Ram Savan
- Department of Immunology, School of Medicine, University of WashingtonSeattleUnited States
- Center for Innate Immunity and Immune Disease, University of WashingtonSeattleUnited States
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2', 5'-Oligoadenylate Synthetase 2 (OAS2) Inhibits Zika Virus Replication through Activation of Type Ι IFN Signaling Pathway. Viruses 2020; 12:v12040418. [PMID: 32276512 PMCID: PMC7232345 DOI: 10.3390/v12040418] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/03/2020] [Accepted: 04/06/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND 2', 5'-oligoadenylate synthetase 2 (OAS2) has been known as an antiviral interferon-stimulated gene (ISG). However, the role of OAS2 on Zika virus (ZIKV) replication is still unknown. In this study, we sought to explore the effect of OAS2 on ZIKV replication and its underlying mechanism. METHODS We performed RNA-Seq in A549 cells with or without ZIKV infection. OAS2 or RIG-I was overexpressed by plasmid transfection or knocked down by siRNA in A549 cells. Expression levels of mRNA and protein of selected genes were detected by RT-qPCR and Western Blot, respectively. Interferon stimulated response element (ISRE) activity was examined by dual luciferase assay. RESULTS We found that ZIKV infection induced OAS2 expression through a RIG-I-dependent pathway. OAS2 overexpression inhibited ZIKV replication, while OAS2 knockdown increased ZIKV replication. We observed that OAS2 inhibited ZIKV replication through enhanced IFNβ expression, leading to the activation of the Jak/STAT signaling pathway. CONCLUSION ZIKV infection induced OAS2 expression, which in turn exerted its anti-ZIKV activities through the IFN-activated Jak/STAT signaling pathway.
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Di H, Elbahesh H, Brinton MA. Characteristics of Human OAS1 Isoform Proteins. Viruses 2020; 12:v12020152. [PMID: 32013110 PMCID: PMC7077331 DOI: 10.3390/v12020152] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/20/2020] [Accepted: 01/22/2020] [Indexed: 12/23/2022] Open
Abstract
The human OAS1 (hOAS1) gene produces multiple possible isoforms due to alternative splicing events and sequence variation among individuals, some of which affect splicing. The unique C-terminal sequences of the hOAS1 isoforms could differentially affect synthetase activity, protein stability, protein partner interactions and/or cellular localization. Recombinant p41, p42, p44, p46, p48, p49 and p52 hOAS1 isoform proteins expressed in bacteria were each able to synthesize trimer and higher order 2'-5' linked oligoadenylates in vitro in response to poly(I:C). The p42, p44, p46, p48 and p52 isoform proteins were each able to induce RNase-mediated rRNA cleavage in response to poly(I:C) when overexpressed in HEK293 cells. The expressed levels of the p42 and p46 isoform proteins were higher than those of the other isoforms, suggesting increased stability in mammalian cells. In a yeast two-hybrid screen, Fibrillin1 (FBN1) was identified as a binding partner for hOAS1 p42 isoform, and Supervillin (SVIL) as a binding partner for the p44 isoform. The p44-SVIL interaction was supported by co-immunoprecipitation data from mammalian cells. The data suggest that the unique C-terminal regions of hOAS1 isoforms may mediate the recruitment of different partners, alternative functional capacities and/or different cellular localization.
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Affiliation(s)
- Han Di
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA; (H.D.); (H.E.)
| | - Husni Elbahesh
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA; (H.D.); (H.E.)
- Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Margo A. Brinton
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA; (H.D.); (H.E.)
- Correspondence:
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RNase L Antiviral Activity Is Not a Critical Component of the Oas1b-Mediated Flavivirus Resistance Phenotype. J Virol 2019; 93:JVI.00946-19. [PMID: 31462564 DOI: 10.1128/jvi.00946-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/21/2019] [Indexed: 01/09/2023] Open
Abstract
In mice, resistance to central nervous system (CNS) disease induced by members of the genus Flavivirus is conferred by an allele of the 2'-5' oligoadenylate synthetase 1b gene that encodes the inactive full-length protein (Oas1b-FL). The susceptibility allele encodes a C-terminally truncated protein (Oas1b-tr). We show that the efficiency of neuron infection in the brains of resistant and susceptible mice is similar after an intracranial inoculation of two flaviviruses, but amplification of viral proteins and double-stranded RNA (dsRNA) is inhibited in infected neurons in resistant mouse brains at later times. Active OAS proteins detect cytoplasmic dsRNA and synthesize short 2'-5'-linked oligoadenylates (2'-5'A) that interact with the latent endonuclease RNase L, causing it to dimerize and cleave single-stranded RNAs. To evaluate the contribution of RNase L to the resistance phenotype in vivo, we created a line of resistant RNase L-/- mice. Evidence of RNase L activation in infected RNase L+/+ mice was indicated by higher levels of viral RNA in the brains of infected RNase L-/- mice. Activation of type I interferon (IFN) signaling was detected in both resistant and susceptible brains, but Oas1a and Oas1b mRNA levels were lower in RNase L+/+ mice of both types, suggesting that activated RNase L also has a proflaviviral effect. Inhibition of virus replication was robust in resistant RNase L-/- mice, indicating that activated RNase L is not a critical factor in mediating this phenotype.IMPORTANCE The mouse genome encodes a family of Oas proteins that synthesize 2'-5'A in response to dsRNA. 2'-5'A activates the endonuclease RNase L to cleave single-stranded viral and cellular RNAs. The inactive, full-length Oas1b protein confers flavivirus-specific disease resistance. Although similar numbers of neurons were infected in resistant and susceptible brains after an intracranial virus infection, viral components amplified only in susceptible brains at later times. A line of resistant RNase L-/- mice was used to evaluate the contribution of RNase L to the resistance phenotype in vivo Activation of RNase L antiviral activity by flavivirus infection was indicated by increased viral RNA levels in the brains of RNase L-/- mice. Oas1a and Oas1b mRNA levels were higher in infected RNase L-/- mice, indicating that activated RNase L also have a proflaviviral affect. However, the resistance phenotype was equally robust in RNase L-/- and RNase L+/+ mice.
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10
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Peterson E, Shippee E, Brinton MA, Kaur P. Biochemical characterization of the mouse ABCF3 protein, a partner of the flavivirus-resistance protein OAS1B. J Biol Chem 2019; 294:14937-14952. [PMID: 31413116 DOI: 10.1074/jbc.ra119.008477] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 08/12/2019] [Indexed: 11/06/2022] Open
Abstract
Mammalian ATP-binding cassette (ABC) subfamily F member 3 (ABCF3) is a class 2 ABC protein that has previously been identified as a partner of the mouse flavivirus resistance protein 2',5'-oligoadenylate synthetase 1B (OAS1B). The functions and natural substrates of ABCF3 are not known. In this study, analysis of purified ABCF3 showed that it is an active ATPase, and binding analyses with a fluorescent ATP analog suggested unequal contributions by the two nucleotide-binding domains. We further showed that ABCF3 activity is increased by lipids, including sphingosine, sphingomyelin, platelet-activating factor, and lysophosphatidylcholine. However, cholesterol inhibited ABCF3 activity, whereas alkyl ether lipids either inhibited or resulted in a biphasic response, suggesting small changes in lipid structure differentially affect ABCF3 activity. Point mutations in the two nucleotide-binding domains of ABCF3 affected sphingosine-stimulated ATPase activity differently, further supporting different roles for the two catalytic pockets. We propose a model in which pocket 1 is the site of basal catalysis, whereas pocket 2 engages in ligand-stimulated ATP hydrolysis. Co-localization of the ABCF3-OAS1B complex to the virus-remodeled endoplasmic reticulum membrane has been shown before. We also noted that co-expression of ABCF3 and OAS1B in bacteria alleviated growth inhibition caused by expression of OAS1B alone, and ABCF3 significantly enhanced OAS1B levels, indirectly showing interaction between these two proteins in bacterial cells. As viral RNA synthesis requires large amounts of ATP, we conclude that lipid-stimulated ATP hydrolysis may contribute to the reduction in viral RNA production characteristic of the flavivirus resistance phenotype.
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Affiliation(s)
| | - Emma Shippee
- Department of Biology, Georgia State University, Atlanta, Georgia 30303
| | - Margo A Brinton
- Department of Biology, Georgia State University, Atlanta, Georgia 30303
| | - Parjit Kaur
- Department of Biology, Georgia State University, Atlanta, Georgia 30303
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11
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Carey CM, Govande AA, Cooper JM, Hartley MK, Kranzusch PJ, Elde NC. Recurrent Loss-of-Function Mutations Reveal Costs to OAS1 Antiviral Activity in Primates. Cell Host Microbe 2019; 25:336-343.e4. [PMID: 30713099 DOI: 10.1016/j.chom.2019.01.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 10/07/2018] [Accepted: 12/28/2018] [Indexed: 11/16/2022]
Abstract
Immune responses counteract infections but also cause collateral damage to hosts. Oligoadenylate synthetase 1 (OAS1) binds double-stranded RNA from invading viruses and produces 2'-5' linked oligoadenylate (2-5A) to activate ribonuclease L (RNase L), which cleaves RNA to inhibit virus replication. OAS1 can also undergo autoactivation by host RNAs, a potential trade-off to antiviral activity. We investigated functional variation in primate OAS1 as a model for how immune pathways evolve to mitigate costs and observed a surprising frequency of loss-of-function variation. In gorillas, we identified a polymorphism that severely decreases catalytic function, mirroring a common variant in humans that impairs 2-5A synthesis through alternative splicing. OAS1 loss-of-function variation is also common in monkeys, including complete loss of 2-5A synthesis in tamarins. The frequency of loss-of-function alleles suggests that costs associated with OAS1 activation can be so detrimental to host fitness that pathogen-protective effects are repeatedly forfeited.
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Affiliation(s)
- Clayton M Carey
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Apurva A Govande
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Juliane M Cooper
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Melissa K Hartley
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Philip J Kranzusch
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Nels C Elde
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
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12
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Manet C, Roth C, Tawfik A, Cantaert T, Sakuntabhai A, Montagutelli X. Host genetic control of mosquito-borne Flavivirus infections. Mamm Genome 2018; 29:384-407. [PMID: 30167843 PMCID: PMC7614898 DOI: 10.1007/s00335-018-9775-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/20/2018] [Indexed: 12/12/2022]
Abstract
Flaviviruses are arthropod-borne viruses, several of which represent emerging or re-emerging pathogens responsible for widespread infections with consequences ranging from asymptomatic seroconversion to severe clinical diseases and congenital developmental deficits. This variability is due to multiple factors including host genetic determinants, the role of which has been investigated in mouse models and human genetic studies. In this review, we provide an overview of the host genes and variants which modify susceptibility or resistance to major mosquito-borne flaviviruses infections in mice and humans.
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Affiliation(s)
- Caroline Manet
- Mouse Genetics Laboratory, Department of Genomes and Genetics, Institut Pasteur, Paris, France
| | - Claude Roth
- Functional Genetics of Infectious Diseases Unit, Department of Genomes and Genetics, Institut Pasteur, Paris, France
- CNRS, UMR 2000-Génomique Evolutive, Modélisation et Santé, Institut Pasteur, 75015, Paris, France
| | - Ahmed Tawfik
- Functional Genetics of Infectious Diseases Unit, Department of Genomes and Genetics, Institut Pasteur, Paris, France
- CNRS, UMR 2000-Génomique Evolutive, Modélisation et Santé, Institut Pasteur, 75015, Paris, France
| | - Tineke Cantaert
- Immunology Group, Institut Pasteur du Cambodge, International Network of Pasteur Institutes, Phnom Penh, 12201, Cambodia
| | - Anavaj Sakuntabhai
- Functional Genetics of Infectious Diseases Unit, Department of Genomes and Genetics, Institut Pasteur, Paris, France.
- CNRS, UMR 2000-Génomique Evolutive, Modélisation et Santé, Institut Pasteur, 75015, Paris, France.
| | - Xavier Montagutelli
- Mouse Genetics Laboratory, Department of Genomes and Genetics, Institut Pasteur, Paris, France.
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13
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Conserved Active-Site Residues Associated with OAS Enzyme Activity and Ubiquitin-Like Domains Are Not Required for the Antiviral Activity of goOASL Protein against Avian Tembusu Virus. Viruses 2018; 10:v10070371. [PMID: 30011971 PMCID: PMC6071104 DOI: 10.3390/v10070371] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/27/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022] Open
Abstract
Interferon (IFN)-induced 2′-5′-oligoadenylate synthetase (OAS) proteins exhibit an extensive and efficient antiviral effect against flavivirus infection in mammals and birds. Only the 2′-5′-oligoadenylate synthetase-like (OASL) gene has been identified thus far in birds, except for ostrich, which has both OAS1 and OASL genes. In this study, we first investigated the antiviral activity of goose OASL (goOASL) protein against a duck-origin Tembusu virus (DTMUV) in duck embryo fibroblast cells (DEFs). To investigate the relationship of conserved amino acids that are related to OAS enzyme activity and ubiquitin-like (UBL) domains with the antiviral activity of goOASL, a series of mutant goOASL plasmids was constructed, including goOASL-S64C/D76E/D78E/D144T, goOASL∆UBLs and goOASL∆UBLs-S64C/D76E/D78E/D144T. Interestingly, all these mutant proteins significantly inhibited the replication of DTMUV in DEFs in a dose-dependent manner. Immunofluorescence analysis showed that the goOASL, goOASL-S64C/D76E/D78E/D144T, goOASL∆UBLs and goOASL∆UBLs-S64C/D76E/D78E/D144T proteins were located not only in the cytoplasm where DTMUV replicates but also in the nucleus of DEFs. However, the goOASL and goOASL mutant proteins were mainly colocalized with DTMUV in the cytoplasm of infected cells. Our data indicated that goOASL could significantly inhibit DTMUV replication in vitro, while the active-site residues S64, D76, D78 and D144, which were associated with OAS enzyme activity, the UBL domains were not required for the antiviral activity of goOASL protein.
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14
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Song DJ, Miller M, Beppu A, Rosenthal P, Das S, Karta M, Vuong C, Mehta AK, Croft M, Broide DH. Rhinovirus Infection of ORMDL3 Transgenic Mice Is Associated with Reduced Rhinovirus Viral Load and Airway Inflammation. THE JOURNAL OF IMMUNOLOGY 2017; 199:2215-2224. [PMID: 28827284 DOI: 10.4049/jimmunol.1601412] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 07/27/2017] [Indexed: 01/29/2023]
Abstract
Orosomucoid like 3 (ORMDL3), a gene localized to chromosome 17q21, has been linked in epidemiologic studies to childhood asthma and rhinovirus (RV) infections. As the single nucleotide polymorphisms linking ORMDL3 to asthma are associated with increased expression of ORMDL3, we have used hORMDL3zp3-Cre mice (which have universal increased expression of human ORMDL3) to determine whether infection of these transgenic mice with RV influences levels of airway inflammation or RV viral load. RV infection of hORMDL3zp3-Cre mice resulted in reduced RV viral load assessed by quantitative real-time PCR (lung and airway epithelium), as well as reduced airway inflammation (total bronchoalveolar lavage cells, neutrophils, macrophages, and lymphocytes) compared with RV-infected wild-type mice. Levels of the antiviral pathways including IFNs (IFN-α, IFN-β, IFN-λ) and RNAse L were significantly increased in the lungs of RV-infected hORMDL3zp3-Cre mice. Levels of the antiviral mouse oligoadenylate synthetase (mOas)1g pathway and RNAse L were upregulated in the lungs of unchallenged hORMDL3zp3-Cre mice. In addition, levels of mOas2, but not mOas1 (mOas1a, mOas1b, mOas1g), or mOas3 pathways were significantly more upregulated by IFNs (IFN-α, IFN-β, IFN-λ) in epithelial cells from hORMDL3zp3-Cre mice compared with RV-infected wild-type mouse epithelial cells. RNAse L-deficient mice infected with RV had increased RV viral load. Overall, these studies suggest that increased levels of ORMDL3 contribute to antiviral defense to RV infection in mice through pathways that may include IFNs (IFN-α, IFN-β, IFN-λ), OAS, and RNAse L.
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Affiliation(s)
- Dae Jin Song
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093.,Department of Pediatrics, Korea University College of Medicine, Seoul 03080, Korea; and
| | - Marina Miller
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Andrew Beppu
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Peter Rosenthal
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Sudipta Das
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Maya Karta
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Christine Vuong
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Amit Kumar Mehta
- Division of Immune Regulation, La Jolla Institute, La Jolla, CA 92037
| | - Michael Croft
- Division of Immune Regulation, La Jolla Institute, La Jolla, CA 92037
| | - David H Broide
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093;
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15
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Zhao M, Wan B, Li H, He J, Chen X, Wang L, Wang Y, Xie S, Qiao S, Zhang G. Porcine 2', 5'-oligoadenylate synthetase 2 inhibits porcine reproductive and respiratory syndrome virus replication in vitro. Microb Pathog 2017; 111:14-21. [PMID: 28804020 DOI: 10.1016/j.micpath.2017.08.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 08/08/2017] [Accepted: 08/09/2017] [Indexed: 12/21/2022]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is acknowledged a fulminating infectious pathogen affecting the pig farming industry, and current vaccines and drugs could hardly inhibit this virus. The 2', 5'-oligoadenylate synthetase (OASs) have antiviral activities, but the role(s) played by porcine OAS2 in protection against PRRSV infection are unknown. Here we found that endogenous expression of the porcine OAS2 gene could be promoted by interferon (IFN)-beta or PRRSV infection in porcine alveolar macrophages. Knockdown of porcine OAS2 led to increases in PRRSV replication, and OAS2 expression suppressed replication of PRRSV in a retinoic acid inducible gene I (RIG-I)-dependent manner, anti-PRRSV activity of porcine OAS2 would be lost if RNase L and OAS2 were both silenced. This discovery illustrates a pathway that porcine OAS2 responses to host anti-PRRSV function.
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Affiliation(s)
- Mengmeng Zhao
- College of Animal Husbandry and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China
| | - Bo Wan
- College of Animal Husbandry and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China
| | - Huawei Li
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China
| | - Jian He
- College of Animal Husbandry and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China
| | - Xinxin Chen
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China
| | - Linjian Wang
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China
| | - Yinbiao Wang
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China
| | - Sha Xie
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China
| | - Songlin Qiao
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China.
| | - Gaiping Zhang
- College of Animal Husbandry and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, People's Republic of China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, People's Republic of China.
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16
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Oas1b-dependent Immune Transcriptional Profiles of West Nile Virus Infection in the Collaborative Cross. G3-GENES GENOMES GENETICS 2017; 7:1665-1682. [PMID: 28592649 PMCID: PMC5473748 DOI: 10.1534/g3.117.041624] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The oligoadenylate-synthetase (Oas) gene locus provides innate immune resistance to virus infection. In mouse models, variation in the Oas1b gene influences host susceptibility to flavivirus infection. However, the impact of Oas variation on overall innate immune programming and global gene expression among tissues and in different genetic backgrounds has not been defined. We examined how Oas1b acts in spleen and brain tissue to limit West Nile virus (WNV) susceptibility and disease across a range of genetic backgrounds. The laboratory founder strains of the mouse Collaborative Cross (CC) (A/J, C57BL/6J, 129S1/SvImJ, NOD/ShiLtJ, and NZO/HlLtJ) all encode a truncated, defective Oas1b, whereas the three wild-derived inbred founder strains (CAST/EiJ, PWK/PhJ, and WSB/EiJ) encode a full-length OAS1B protein. We assessed disease profiles and transcriptional signatures of F1 hybrids derived from these founder strains. F1 hybrids included wild-type Oas1b (F/F), homozygous null Oas1b (N/N), and heterozygous offspring of both parental combinations (F/N and N/F). These mice were challenged with WNV, and brain and spleen samples were harvested for global gene expression analysis. We found that the Oas1b haplotype played a role in WNV susceptibility and disease metrics, but the presence of a functional Oas1b allele in heterozygous offspring did not absolutely predict protection against disease. Our results indicate that Oas1b status as wild-type or truncated, and overall Oas1b gene dosage, link with novel innate immune gene signatures that impact specific biological pathways for the control of flavivirus infection and immunity through both Oas1b-dependent and independent processes.
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17
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Li Y, Banerjee S, Goldstein SA, Dong B, Gaughan C, Rath S, Donovan J, Korennykh A, Silverman RH, Weiss SR. Ribonuclease L mediates the cell-lethal phenotype of double-stranded RNA editing enzyme ADAR1 deficiency in a human cell line. eLife 2017; 6. [PMID: 28362255 PMCID: PMC5404912 DOI: 10.7554/elife.25687] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/30/2017] [Indexed: 12/13/2022] Open
Abstract
ADAR1 isoforms are adenosine deaminases that edit and destabilize double-stranded RNA reducing its immunostimulatory activities. Mutation of ADAR1 leads to a severe neurodevelopmental and inflammatory disease of children, Aicardi-Goutiéres syndrome. In mice, Adar1 mutations are embryonic lethal but are rescued by mutation of the Mda5 or Mavs genes, which function in IFN induction. However, the specific IFN regulated proteins responsible for the pathogenic effects of ADAR1 mutation are unknown. We show that the cell-lethal phenotype of ADAR1 deletion in human lung adenocarcinoma A549 cells is rescued by CRISPR/Cas9 mutagenesis of the RNASEL gene or by expression of the RNase L antagonist, murine coronavirus NS2 accessory protein. Our result demonstrate that ablation of RNase L activity promotes survival of ADAR1 deficient cells even in the presence of MDA5 and MAVS, suggesting that the RNase L system is the primary sensor pathway for endogenous dsRNA that leads to cell death. DOI:http://dx.doi.org/10.7554/eLife.25687.001
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Affiliation(s)
- Yize Li
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Shuvojit Banerjee
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, United States
| | - Stephen A Goldstein
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Beihua Dong
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, United States
| | - Christina Gaughan
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, United States
| | - Sneha Rath
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Jesse Donovan
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Alexei Korennykh
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Robert H Silverman
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, United States
| | - Susan R Weiss
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
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18
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Tag-El-Din-Hassan HT, Sasaki N, Torigoe D, Morimatsu M, Agui T. Analysis of the Relationship Between Enzymatic and Antiviral Activities of the Chicken Oligoadenylate Synthetase-Like. J Interferon Cytokine Res 2017; 37:71-80. [DOI: 10.1089/jir.2016.0012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Hassan T. Tag-El-Din-Hassan
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
- Poultry Production Department, Faculty of Agriculture, Mansoura University, Mansoura, Egypt
| | - Nobuya Sasaki
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Daisuke Torigoe
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Masami Morimatsu
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Takashi Agui
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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19
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Elkhateeb E, Tag-El-Din-Hassan HT, Sasaki N, Torigoe D, Morimatsu M, Agui T. The role of mouse 2',5'-oligoadenylate synthetase 1 paralogs. INFECTION GENETICS AND EVOLUTION 2016; 45:393-401. [PMID: 27663720 DOI: 10.1016/j.meegid.2016.09.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/30/2016] [Accepted: 09/19/2016] [Indexed: 10/21/2022]
Abstract
The interferon-induced oligoadenylate synthetase (OAS) family is one of the most important immune response proteins to the viral infection. The OAS protein binds dsRNA and is activated to produce 2',5'-oligoadenylates, which lead to the activation of latent form of RNase L, resulting in degradation of cellular and viral RNA and inhibition of viral replication. In mice, the Oas gene family locates on chromosome 5. The mouse Oas gene locus undergoes a recent series of duplication event, leading to the presence of eight paralogs of Oas1 genes (Oas1a through Oas1h) that forms Oas gene cluster with the Oas2, Oas3 and two OasL (OasL1 and OasL2) genes. Previous studies demonstrated that the mouse Oas1b gene conferred resistance to the flavivirus infection in mice; however, the antiviral activity of other mouse Oas1 gene family is still unknown. Therefore, in the present study, we have evaluated the mouse Oas1 paralogs regarding the enzymatic activity and antiviral activity against the two neurotropic flaviviruses, West Nile virus and tick-borne encephalitis virus. The mouse Oas1 genes were cloned from C57BL/6J (B6) as well as the Oas1b derived from feral mouse strain, MSM. The obtained results demonstrated that only Oas1a and Oas1g showed enzymatic activity. Although MSM-derived Oas1b showed antiviral activity to both viruses, all B6-derived OAS paralogs did not show antiviral activity. These results suggest that Oas1a and Oas1g play a role in potentiating viral RNA-induced interferon response in the cell, whereas the Oas1b works as a specific anti-flavivirus factor unless it is mutated. However, the role of other paralogs is unknown and should wait for further investigation.
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Affiliation(s)
- Enas Elkhateeb
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Hassan T Tag-El-Din-Hassan
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan; Poultry Production Department, Faculty of Agriculture, Mansoura University, Mansoura, Egypt
| | - Nobuya Sasaki
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Daisuke Torigoe
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Masami Morimatsu
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Takashi Agui
- Laboratory of Laboratory Animal Science and Medicine, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
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20
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Banerjee S. RNase L and the NLRP3-inflammasome: An old merchant in a new trade. Cytokine Growth Factor Rev 2016; 29:63-70. [PMID: 26987611 DOI: 10.1016/j.cytogfr.2016.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/27/2016] [Indexed: 12/12/2022]
Abstract
The type I/III interferon (IFN)-inducible 2'-5'- oligoadenylate synthetase (OAS)/endoribonuclease L (RNase L) is a classical innate immune pathway that has been implicated in antiviral and antibacterial defense and also in hereditary prostate cancer. The OAS/RNase L pathway is activated when OAS senses double-stranded RNA and catalyzes the synthesis of 2'-5' linked oligodenylates (2-5A) from ATP. 2-5A then binds and activates RNase L, resulting cleavage of single-stranded RNAs. RNase L cleavage products are capable of activating RIG-like receptors such as RIG-I and MDA5 that leads to IFN-β expression during viral infection. Our recent findings suggest that beside the RLR pathway, RNase L cleavage products can also activate the NLRP3-inflammasome pathway, which requires DHX33 (DExD/H-box helicase) and the mitochondrial adaptor protein MAVS. Here we discuss this newly identified role of OAS-RNase L pathway in regulation of inflammasome signaling as an alternative antimicrobial mechanism that has potential as a target for development of new broad-spectrum antimicrobial and anti-inflammatory therapies.
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Affiliation(s)
- Shuvojit Banerjee
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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21
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Activation of RNase L is dependent on OAS3 expression during infection with diverse human viruses. Proc Natl Acad Sci U S A 2016; 113:2241-6. [PMID: 26858407 DOI: 10.1073/pnas.1519657113] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The 2',5'-oligoadenylate (2-5A) synthetase (OAS)-RNase L system is an IFN-induced antiviral pathway. RNase L activity depends on 2-5A, synthesized by OAS. Although all three enzymatically active OAS proteins in humans--OAS1, OAS2, and OAS3--synthesize 2-5A upon binding dsRNA, it is unclear which are responsible for RNase L activation during viral infection. We used clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology to engineer human A549-derived cell lines in which each of the OAS genes or RNase L is knocked out. Upon transfection with poly(rI):poly(rC), a synthetic surrogate for viral dsRNA, or infection with each of four viruses from different groups (West Nile virus, Sindbis virus, influenza virus, or vaccinia virus), OAS1-KO and OAS2-KO cells synthesized amounts of 2-5A similar to those synthesized in parental wild-type cells, causing RNase L activation as assessed by rRNA degradation. In contrast, OAS3-KO cells synthesized minimal 2-5A, and rRNA remained intact, similar to infected RNase L-KO cells. All four viruses replicated to higher titers in OAS3-KO or RNase L-KO A549 cells than in parental, OAS1-KO, or OAS2-KO cells, demonstrating the antiviral effects of OAS3. OAS3 displayed a higher affinity for dsRNA in intact cells than either OAS1 or OAS2, consistent with its dominant role in RNase L activation. Finally, the requirement for OAS3 as the major OAS isoform responsible for RNase L activation was not restricted to A549 cells, because OAS3-KO cells derived from two other human cell lines also were deficient in RNase L activation.
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22
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Zheng S, Zhu D, Lian X, Liu W, Cao R, Chen P. Porcine 2′, 5′-oligoadenylate synthetases inhibit Japanese encephalitis virus replication in vitro. J Med Virol 2015; 88:760-8. [DOI: 10.1002/jmv.24397] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Sheng Zheng
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
| | - Dan Zhu
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
| | - Xue Lian
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
| | - Weiting Liu
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
| | - Ruibing Cao
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
| | - Puyan Chen
- Key Laboratory of Animal Diseases Diagnosis and Immunology, Ministry of Agriculture, College of Veterinary Medicine; Nanjing Agricultural University; Nanjing China
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Wood ER, Bledsoe R, Chai J, Daka P, Deng H, Ding Y, Harris-Gurley S, Kryn LH, Nartey E, Nichols J, Nolte RT, Prabhu N, Rise C, Sheahan T, Shotwell JB, Smith D, Tai V, Taylor JD, Tomberlin G, Wang L, Wisely B, You S, Xia B, Dickson H. The Role of Phosphodiesterase 12 (PDE12) as a Negative Regulator of the Innate Immune Response and the Discovery of Antiviral Inhibitors. J Biol Chem 2015; 290:19681-96. [PMID: 26055709 PMCID: PMC4528132 DOI: 10.1074/jbc.m115.653113] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 05/20/2015] [Indexed: 11/06/2022] Open
Abstract
2',5'-Oligoadenylate synthetase (OAS) enzymes and RNase-L constitute a major effector arm of interferon (IFN)-mediated antiviral defense. OAS produces a unique oligonucleotide second messenger, 2',5'-oligoadenylate (2-5A), that binds and activates RNase-L. This pathway is down-regulated by virus- and host-encoded enzymes that degrade 2-5A. Phosphodiesterase 12 (PDE12) was the first cellular 2-5A- degrading enzyme to be purified and described at a molecular level. Inhibition of PDE12 may up-regulate the OAS/RNase-L pathway in response to viral infection resulting in increased resistance to a variety of viral pathogens. We generated a PDE12-null cell line, HeLaΔPDE12, using transcription activator-like effector nuclease-mediated gene inactivation. This cell line has increased 2-5A levels in response to IFN and poly(I-C), a double-stranded RNA mimic compared with the parental cell line. Moreover, HeLaΔPDE12 cells were resistant to viral pathogens, including encephalomyocarditis virus, human rhinovirus, and respiratory syncytial virus. Based on these results, we used DNA-encoded chemical library screening to identify starting points for inhibitor lead optimization. Compounds derived from this effort raise 2-5A levels and exhibit antiviral activity comparable with the effects observed with PDE12 gene inactivation. The crystal structure of PDE12 complexed with an inhibitor was solved providing insights into the structure-activity relationships of inhibitor potency and selectivity.
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Affiliation(s)
| | | | - Jing Chai
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | - Philias Daka
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
| | - Hongfeng Deng
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | - Yun Ding
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | | | | | | | | | | | - Ninad Prabhu
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | - Cecil Rise
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | - Timothy Sheahan
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
| | - J Brad Shotwell
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
| | | | - Vince Tai
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
| | | | | | | | | | - Shihyun You
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
| | - Bing Xia
- ELT Boston, GlaxoSmithKline, Waltham, Massachusetts 02451
| | - Hamilton Dickson
- Antiviral Discovery Performance Unit, GlaxoSmithKline, Research Triangle Park, North Carolina 27709 and
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Silverman RH, Weiss SR. Viral phosphodiesterases that antagonize double-stranded RNA signaling to RNase L by degrading 2-5A. J Interferon Cytokine Res 2015; 34:455-63. [PMID: 24905202 DOI: 10.1089/jir.2014.0007] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The host interferon (IFN) antiviral response involves a myriad of diverse biochemical pathways that disrupt virus replication cycles at many different levels. As a result, viruses have acquired and evolved genes that antagonize the host antiviral proteins. IFNs inhibit viral infections in part through the 2',5'-oligoadenylate (2-5A) synthetase (OAS)/RNase L pathway. OAS proteins are pathogen recognition receptors that exist at different basal levels in different cell types and that are IFN inducible. Upon activation by the pathogen-associated molecular pattern viral double-stranded RNA, certain OAS proteins synthesize 2-5A from ATP. 2-5A binds to the antiviral enzyme RNase L causing its dimerization and activation. Recently, disparate RNA viruses, group 2a betacoronaviruses, and group A rotaviruses, have been shown to produce proteins with 2',5'-phosphodiesterase (PDE) activities that eliminate 2-5A thereby evading the antiviral activity of the OAS/RNase L pathway. These viral proteins are members of the eukaryotic-viral LigT-like group of 2H phosphoesterases, so named for the presence of 2 conserved catalytic histidine residues. Here, we will review the biochemistry, biology, and implications of viral and cellular 2',5'-PDEs that degrade 2-5A. In addition, we discuss alternative viral and cellular strategies for limiting the activity of OAS/RNase L.
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Affiliation(s)
- Robert H Silverman
- 1 Department of Cancer Biology, Lerner Research Institute , Cleveland Clinic, Cleveland, Ohio
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25
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Affiliation(s)
- Margo A Brinton
- Department of Biology, Georgia State University , Atlanta, Georgia
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26
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Quicke KM, Suthar MS. The innate immune playbook for restricting West Nile virus infection. Viruses 2013; 5:2643-58. [PMID: 24178712 PMCID: PMC3856407 DOI: 10.3390/v5112643] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Revised: 10/19/2013] [Accepted: 10/22/2013] [Indexed: 01/07/2023] Open
Abstract
West Nile virus (WNV) is an emerging mosquito-borne flavivirus that causes annual epidemics of encephalitic disease throughout the world. Despite the ongoing risk to public health, no approved vaccines or therapies exist for use in humans to prevent or combat WNV infection. The innate immune response is critical for controlling WNV replication, limiting virus-induced pathology, and programming protective humoral and cell-mediated immunity to WNV infection. The RIG-I like receptors, Toll-like receptors, and Nod-like receptors detect and respond to WNV by inducing a potent antiviral defense program, characterized by production of type I IFN, IL-1β and expression of antiviral effector genes. Recent research efforts have focused on uncovering the mechanisms of innate immune sensing, antiviral effector genes that inhibit WNV, and countermeasures employed by WNV to antagonize innate immune cellular defenses. In this review, we highlight the major research findings pertaining to innate immune regulation of WNV infection.
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Affiliation(s)
- Kendra M Quicke
- Department of Pediatrics and Children's Healthcare of Atlanta and Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30329, USA.
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27
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Homologous 2',5'-phosphodiesterases from disparate RNA viruses antagonize antiviral innate immunity. Proc Natl Acad Sci U S A 2013; 110:13114-9. [PMID: 23878220 DOI: 10.1073/pnas.1306917110] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Efficient and productive virus infection often requires viral countermeasures that block innate immunity. The IFN-inducible 2',5'-oligoadenylate (2-5A) synthetases (OASs) and ribonuclease (RNase) L are components of a potent host antiviral pathway. We previously showed that murine coronavirus (MHV) accessory protein ns2, a 2H phosphoesterase superfamily member, is a phosphodiesterase (PDE) that cleaves 2-5A, thereby preventing activation of RNase L. The PDE activity of ns2 is required for MHV replication in macrophages and for hepatitis. Here, we show that group A rotavirus (RVA), an important cause of acute gastroenteritis in children worldwide, encodes a similar PDE. The RVA PDE forms the carboxy-terminal domain of the minor core protein VP3 (VP3-CTD) and shares sequence and predicted structural homology with ns2, including two catalytic HxT/S motifs. Bacterially expressed VP3-CTD exhibited 2',5'-PDE activity, which cleaved 2-5A in vitro. In addition, VP3-CTD expressed transiently in mammalian cells depleted 2-5A levels induced by OAS activation with poly(rI):poly(rC), preventing RNase L activation. In the context of recombinant chimeric MHV expressing inactive ns2, VP3-CTD restored the ability of the virus to replicate efficiently in macrophages or in the livers of infected mice, whereas mutant viruses expressing inactive VP3-CTD (H718A or H798R) were attenuated. In addition, chimeric viruses expressing either active ns2 or VP3-CTD, but not nonfunctional equivalents, were able to protect ribosomal RNA from RNase L-mediated degradation. Thus, VP3-CTD is a 2',5'-PDE able to functionally substitute for ns2 in MHV infection. Remarkably, therefore, two disparate RNA viruses encode proteins with homologous 2',5'-PDEs that antagonize activation of innate immunity.
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Suthar MS, Brassil MM, Blahnik G, McMillan A, Ramos HJ, Proll SC, Belisle SE, Katze MG, Gale M. A systems biology approach reveals that tissue tropism to West Nile virus is regulated by antiviral genes and innate immune cellular processes. PLoS Pathog 2013; 9:e1003168. [PMID: 23544010 PMCID: PMC3567171 DOI: 10.1371/journal.ppat.1003168] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 12/18/2012] [Indexed: 12/13/2022] Open
Abstract
The actions of the RIG-I like receptor (RLR) and type I interferon (IFN) signaling pathways are essential for a protective innate immune response against the emerging flavivirus West Nile virus (WNV). In mice lacking RLR or IFN signaling pathways, WNV exhibits enhanced tissue tropism, indicating that specific host factors of innate immune defense restrict WNV infection and dissemination in peripheral tissues. However, the immune mechanisms by which the RLR and IFN pathways coordinate and function to impart restriction of WNV infection are not well defined. Using a systems biology approach, we defined the host innate immune response signature and actions that restrict WNV tissue tropism. Transcriptional profiling and pathway modeling to compare WNV-infected permissive (spleen) and nonpermissive (liver) tissues showed high enrichment for inflammatory responses, including pattern recognition receptors and IFN signaling pathways, that define restriction of WNV replication in the liver. Assessment of infected livers from Mavs−/−×Ifnar−/− mice revealed the loss of expression of several key components within the natural killer (NK) cell signaling pathway, including genes associated with NK cell activation, inflammatory cytokine production, and NK cell receptor signaling. In vivo analysis of hepatic immune cell infiltrates from WT mice demonstrated that WNV infection leads to an increase in NK cell numbers with enhanced proliferation, maturation, and effector action. In contrast, livers from Mavs−/−×Ifnar−/− infected mice displayed reduced immune cell infiltration, including a significant reduction in NK cell numbers. Analysis of cocultures of dendritic and NK cells revealed both cell-intrinsic and -extrinsic roles for the RLR and IFN signaling pathways to regulate NK cell effector activity. Taken together, these observations reveal a complex innate immune signaling network, regulated by the RLR and IFN signaling pathways, that drives tissue-specific antiviral effector gene expression and innate immune cellular processes that control tissue tropism to WNV infection. West Nile virus (WNV), a mosquito-transmitted RNA flavivirus, is an NIAID Category B infectious agent that has emerged in the Western hemisphere as a serious public health threat. The innate immune effectors that impart restriction of WNV infection are not well defined. WNV infection is sensed by the host RIG-I like receptors (RLR), a class of pattern recognition receptors, to trigger type I interferon (IFN) and related innate immune defense programs. Using a systems biology approach, we evaluated the contribution of the RLR and type I IFN signaling pathways in controlling tissue tropism. WNV infection triggers tissue-specific innate immune responses, specifically antiviral effector genes and natural killer (NK) cell signaling related genes, which are directly regulated by the combined actions of the RLR and type I IFN signaling pathways. Cocultures of dendritic and NK cells revealed that RLR and type I IFN signaling pathways are essential in promoting NK cell activation during WNV infection. Our observations indicate that combined RLR- and type I IFN-dependent signaling programs drive specific antiviral effector gene expression and programs NK cell responses that, together, serve to restrict WNV tissue tropism.
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Affiliation(s)
- Mehul S. Suthar
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Margaret M. Brassil
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Gabriele Blahnik
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Aimee McMillan
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Hilario J. Ramos
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Sean C. Proll
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Sarah E. Belisle
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michael G. Katze
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michael Gale
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
- * E-mail:
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29
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Suthar MS, Diamond MS, Gale Jr M. West Nile virus infection and immunity. Nat Rev Microbiol 2013; 11:115-28. [DOI: 10.1038/nrmicro2950] [Citation(s) in RCA: 300] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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30
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Susceptibility to flavivirus-specific antiviral response of Oas1b affects the neurovirulence of the Far-Eastern subtype of tick-borne encephalitis virus. Arch Virol 2012; 158:1039-46. [PMID: 23266832 DOI: 10.1007/s00705-012-1579-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 10/10/2012] [Indexed: 12/30/2022]
Abstract
Tick-borne encephalitis virus (TBEV) is a zoonotic agent that causes fatal encephalitis in humans. 2'-5'-oligoadenylate synthetase 1b (Oas1b) has been identified as a flavivirus resistance gene, but most inbred laboratory mice do not possess a functional Oas1b gene. In this study, a congenic strain carrying a functional Oas1b gene, B6.MSM-Oas, was used to evaluate the pathogenicity of Far-Eastern TBEV. Although intracerebral infection of B6.MSM-Oas mice by Oshima 5-10 resulted in limited signs of illness, infection by Sofjin-HO resulted in death with severe neurologic signs. While Oshima 5-10 was cleared from the brain, Sofjin-HO was not cleared despite a similar level of expression of the intact Oas1b gene. Necrotic neurons with viral antigens and inflammatory reactions were observed in the brain infected with Sofjin-HO. These data indicate that the different susceptibility to the antiviral activity of Oas1b resulted in a difference in neurovirulence in the two TBEV strains.
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31
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Zhao L, Jha BK, Wu A, Elliott R, Ziebuhr J, Gorbalenya AE, Silverman RH, Weiss SR. Antagonism of the interferon-induced OAS-RNase L pathway by murine coronavirus ns2 protein is required for virus replication and liver pathology. Cell Host Microbe 2012; 11:607-16. [PMID: 22704621 PMCID: PMC3377938 DOI: 10.1016/j.chom.2012.04.011] [Citation(s) in RCA: 212] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 03/26/2012] [Accepted: 04/17/2012] [Indexed: 01/19/2023]
Abstract
Many viruses induce hepatitis in humans, highlighting the need to understand the underlying mechanisms of virus-induced liver pathology. The murine coronavirus, mouse hepatitis virus (MHV), causes acute hepatitis in its natural host and provides a useful model for understanding virus interaction with liver cells. The MHV accessory protein, ns2, antagonizes the type I interferon response and promotes hepatitis. We show that ns2 has 2′,5′-phosphodiesterase activity, which blocks the interferon inducible 2′,5′-oligoadenylate synthetase (OAS)-RNase L pathway to facilitate hepatitis development. Ns2 cleaves 2′,5′-oligoadenylate, the product of OAS, to prevent activation of the cellular endoribonuclease RNase L and consequently block viral RNA degradation. An ns2 mutant virus was unable to replicate in the liver or induce hepatitis in wild-type mice, but was highly pathogenic in RNase L deficient mice. Thus, RNase L is a critical cellular factor for protection against viral infection of the liver and the resulting hepatitis.
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Affiliation(s)
- Ling Zhao
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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32
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Diamond MS, Gale M. Cell-intrinsic innate immune control of West Nile virus infection. Trends Immunol 2012; 33:522-30. [PMID: 22726607 DOI: 10.1016/j.it.2012.05.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 05/15/2012] [Accepted: 05/18/2012] [Indexed: 12/25/2022]
Abstract
West Nile virus (WNV) is an enveloped positive-stranded RNA virus that has emerged over the past decade in North America to cause epidemics of meningitis, encephalitis, and acute flaccid paralysis in humans. WNV has broad species specificity, and replicates efficiently in many cell types, including those of the innate immune and central nervous systems. Recent studies have defined the pathogen recognition receptor (PRR) and signaling pathways by which WNV is detected, and several effector mechanisms that contribute to protective cell-intrinsic immunity. This review focuses on recent advances in identifying the host sensors that detect WNV, the adaptor molecules and signaling pathways that regulate the induction of interferon (IFN)-dependent defenses, and the proteins that limit WNV replication, spread, and disease pathogenesis.
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Affiliation(s)
- Michael S Diamond
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO 63110, USA.
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33
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Identification of novel host cell binding partners of Oas1b, the protein conferring resistance to flavivirus-induced disease in mice. J Virol 2012; 86:7953-63. [PMID: 22623793 DOI: 10.1128/jvi.00333-12] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Oas1b was previously identified as the product of the Flv(r) allele that confers flavivirus-specific resistance to virus-induced disease in mice by an uncharacterized, RNase L-independent mechanism. To gain insights about the mechanism by which Oas1b specifically reduces the efficiency of flavivirus replication, cellular protein interaction partners were identified and their involvement in the Oas1b-mediated flavivirus resistance mechanism was analyzed. Initial difficulties in getting the two-hybrid assay to work with full-length Oas1b led to the discovery that this Oas protein uniquely has a C-terminal transmembrane domain that targets it to the endoplasmic reticulum (ER). Two peptides matching to oxysterol binding protein-related protein 1L (ORP1L) and ATP binding cassette protein 3, subfamily F (ABCF3), were identified as Oas1b interaction partners in yeast two-hybrid assays, and both in vitro-transcribed/translated peptides and full-length proteins in mammalian cell lysates coimmunoprecipitated with Oas1b. Knockdown of a partner involved in Oas1b-mediated antiflavivirus activity would be expected to increase flavivirus replication but not that of other types of viruses. However, RNA interference (RNAi) knockdown of ORP1L decreased the replication of the flavivirus West Nile virus (WNV) as well as that of other types of RNA viruses. This virus-nonspecific effect may be due to the recently reported dysregulation of late endosome movement by ORP1L knockdown. Knockdown of ABCF3 protein levels increased the replication of WNV but not that of other types of RNA viruses, and this effect on WNV replication was observed only in Oas1b-expressing cells. The results suggest that Oas1b is part of a complex located in the ER and that ABCF3 is a component of the Flv(r)-mediated resistance mechanism.
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Pulit-Penaloza JA, Scherbik SV, Brinton MA. Type 1 IFN-independent activation of a subset of interferon stimulated genes in West Nile virus Eg101-infected mouse cells. Virology 2012; 425:82-94. [PMID: 22305622 PMCID: PMC3288888 DOI: 10.1016/j.virol.2012.01.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 10/10/2011] [Accepted: 01/09/2012] [Indexed: 12/24/2022]
Abstract
Although infection of mouse embryofibroblasts (MEFs) with WNV Eg101 induced interferon (IFN) beta production and STAT1 and STAT2 phosphorylation, these transcription factors (TFs) were not detected in the nucleus or on the promoters of four IRF-3-independent interferon stimulated genes (ISGs): Oas1a and Irf7 (previously characterized as IFN/ISGF3-dependent), Oas1b and Irf1. These ISGs were upregulated in WNV Eg101-infected STAT1-/-, STAT2-/-, and IFN alpha/beta receptor-/- MEFs. Although either IRF-3 or IRF-7 could amplify/sustain Oas1a and Oas1b upregulation at later times after infection, these factors were not required for the initial gene activation. The lack of upregulation of these ISGs in WNV Eg101-infected IRF-3/9-/- MEFs suggested the involvement of IRF-9. Activation of Irf1 in infected MEFs did not depend on any of these IRFs. The data indicate that additional alternative activation mechanisms exist for subsets of ISGs when a virus infection has blocked ISG activation by the canonical IFN-mediated pathway.
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Affiliation(s)
| | | | - Margo A. Brinton
- Department of Biology, Georgia State University, Atlanta, Georgia 30302
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35
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Monath TP. Review of the risks and benefits of yellow fever vaccination including some new analyses. Expert Rev Vaccines 2012; 11:427-448. [DOI: 10.1586/erv.12.6] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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36
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Pulit-Penaloza JA, Scherbik SV, Brinton MA. Activation of Oas1a gene expression by type I IFN requires both STAT1 and STAT2 while only STAT2 is required for Oas1b activation. Virology 2012; 425:71-81. [PMID: 22305621 DOI: 10.1016/j.virol.2011.11.025] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 09/15/2011] [Accepted: 11/29/2011] [Indexed: 12/24/2022]
Abstract
The murine 2'-5' oligoadenylate synthetase 1a (Oas1a) and Oas1b genes are type 1 IFN responsive genes. Oas1a is an active synthetase with broad antiviral activity mediated through RNase L. Oas1b is inactive but can inhibit Oas1a synthetase activity and mediate a flavivirus-specific antiviral activity through an unknown RNase L-independent mechanism. Analysis of promoter elements regulating gene transcription confirmed that an IFN-stimulated response element (ISRE) is required for IFN beta-activation but neither the overlapping IRF binding site present in both promoters nor the adjacent Oas1b NF-kappa B site is required. Mutation of the overlapping STAT site negatively affected IFN beta-induction of Oas1a but not of Oas1b. Also, IFN beta induction of Oas1a was STAT1- and STAT2-dependent, while induction of Oas1b was STAT1-independent but STAT2-dependent. The two promoters differ at a single nucleotide in the STAT site. The data indicate that these two duplicated genes can be differentially regulated by IFN beta.
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37
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Strobl B, Leitner NR, Müller M. Multifaceted Antiviral Actions of Interferon-stimulated Gene Products. JAK-STAT SIGNALING : FROM BASICS TO DISEASE 2012. [PMCID: PMC7121797 DOI: 10.1007/978-3-7091-0891-8_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Interferons (IFNs) are extremely powerful cytokines for the host defence against viral infections. Binding of IFNs to their receptors activates the JAK/STAT signalling pathway with the Janus kinases JAK1, 2 and TYK2 and the signal transducer and activators of transcription (STAT) 1 and STAT2. Depending on the cellular setting, additional STATs (STAT3-6) and additional signalling pathways are activated. The actions of IFNs on infected cells and the surrounding tissue are mediated by the induction of several hundred IFN-stimulated genes (ISGs). Since the cloning of the first ISGs, considerable progress has been made in describing antiviral effector proteins and their many modes of action. Effector proteins individually target distinct steps in the viral life cycle, including blocking virus entry, inhibition of viral transcription and translation, modification of viral nucleic acids and proteins and, interference with virus assembly and budding. Novel pathways of viral inhibition are constantly being elucidated and, additionally, unanticipated functions of known antiviral effector proteins are discovered. Herein, we outline IFN-induced antiviral pathways and review recent developments in this fascinating area of research.
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38
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Bigham AW, Buckingham KJ, Husain S, Emond MJ, Bofferding KM, Gildersleeve H, Rutherford A, Astakhova NM, Perelygin AA, Busch MP, Murray KO, Sejvar JJ, Green S, Kriesel J, Brinton MA, Bamshad M. Host genetic risk factors for West Nile virus infection and disease progression. PLoS One 2011; 6:e24745. [PMID: 21935451 PMCID: PMC3174177 DOI: 10.1371/journal.pone.0024745] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 08/16/2011] [Indexed: 11/19/2022] Open
Abstract
West Nile virus (WNV), a category B pathogen endemic in parts of Africa, Asia and Europe, emerged in North America in 1999, and spread rapidly across the continental U.S. Outcomes of infection with WNV range from asymptomatic to severe neuroinvasive disease manifested as encephalitis, paralysis, and/or death. Neuroinvasive WNV disease occurs in less than one percent of cases, and although host genetic factors are thought to influence risk for symptomatic disease, the identity of these factors remains largely unknown. We tested 360 common haplotype tagging and/or functional SNPs in 86 genes that encode key regulators of immune function in 753 individuals infected with WNV including: 422 symptomatic WNV cases and 331 cases with asymptomatic infections. After applying a Bonferroni correction for multiple tests and controlling for population stratification, SNPs in IRF3 (OR 0.54, p = 0.035) and MX1, (OR 0.19, p = 0.014) were associated with symptomatic WNV infection and a single SNP in OAS1 (OR 9.79, p = 0.003) was associated with increased risk for West Nile encephalitis and paralysis (WNE/P). Together, these results suggest that genetic variation in the interferon response pathway is associated with both risk for symptomatic WNV infection and WNV disease progression.
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Affiliation(s)
- Abigail W. Bigham
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
- * E-mail: (AWB); (MB)
| | - Kati J. Buckingham
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
| | - Sofia Husain
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
| | - Mary J. Emond
- Department of Biostatistics, University of Washington, Seattle, Washington, United States of America
| | - Kathryn M. Bofferding
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
| | - Heidi Gildersleeve
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
| | - Ann Rutherford
- Department of Internal Medicine, Division of Infectious Diseases, University of Utah, Salt Lake City, Utah, United States of America
| | - Natalia M. Astakhova
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Andrey A. Perelygin
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Michael P. Busch
- Blood Systems, San Francisco, California, United States of America
| | - Kristy O. Murray
- School of Public Health, University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - James J. Sejvar
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America
| | - Sharone Green
- Department of Medicine, Center for Infectious Disease and Vaccine Research, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - John Kriesel
- Department of Internal Medicine, Division of Infectious Diseases, University of Utah, Salt Lake City, Utah, United States of America
| | - Margo A. Brinton
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Michael Bamshad
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
- * E-mail: (AWB); (MB)
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Abstract
Type I interferon (IFN) signaling coordinates an early antiviral program in infected and uninfected cells by inducing IFN-stimulated genes (ISGs) that modulate viral entry, replication, and assembly. However, the specific antiviral functions in vivo of most ISGs remain unknown. Here, we examined the contribution of the ISG viperin to the control of West Nile virus (WNV) in genetically deficient cells and mice. While modest increases in levels of WNV replication were observed for primary viperin(-/-) macrophages and dendritic cells, no appreciable differences were detected in deficient embryonic cortical neurons or fibroblasts. In comparison, viperin(-/-) adult mice infected with WNV via the subcutaneous or intracranial route showed increased lethality and/or enhanced viral replication in central nervous system (CNS) tissues. In the CNS, viperin expression was induced in both WNV-infected and adjacent uninfected cells, including activated leukocytes at the site of infection. Our experiments suggest that viperin restricts the infection of WNV in a tissue- and cell-type-specific manner and may be an important ISG for controlling viral infections that cause CNS disease.
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Anderson BR, Muramatsu H, Jha BK, Silverman RH, Weissman D, Karikó K. Nucleoside modifications in RNA limit activation of 2'-5'-oligoadenylate synthetase and increase resistance to cleavage by RNase L. Nucleic Acids Res 2011; 39:9329-38. [PMID: 21813458 PMCID: PMC3241635 DOI: 10.1093/nar/gkr586] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The interferon-induced enzymes 2′-5′-oligoadenylate synthetase (OAS) and RNase L are key components of innate immunity involved in sensory and effector functions following viral infections. Upon binding target RNA, OAS is activated to produce 2′-5′-linked oligoadenylates (2-5A) that activate RNase L, which then cleaves single-stranded self and non-self RNA. Modified nucleosides that are present in cellular transcripts have been shown to suppress activation of several RNA sensors. Here, we demonstrate that in vitro transcribed, unmodified RNA activates OAS, induces RNase L-mediated ribosomal RNA (rRNA) cleavage and is rapidly cleaved by RNase L. In contrast, RNA containing modified nucleosides activates OAS less efficiently and induces limited rRNA cleavage. Nucleoside modifications also make RNA resistant to cleavage by RNase L. Examining translation in RNase L−/− cells and mice confirmed that RNase L activity reduces translation of unmodified mRNA, which is not observed with modified mRNA. Additionally, mRNA containing the nucleoside modification pseudouridine is translated longer and has an extended half-life. The observation that modified nucleosides in RNA reduce 2-5A pathway activation joins OAS and RNase L to the list of RNA sensors and effectors whose functions are limited when RNA is modified, confirming the role of nucleoside modifications in suppressing immune recognition of RNA.
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Affiliation(s)
- Bart R Anderson
- Department of Medicine, 3610 Hamilton Walk, 522B Johnson Pavilion, University of Pennsylvania, Philadelphia, PA 19104, USA
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Vallmann K, Aas N, Reintamm T, Lopp A, Kuusksalu A, Kelve M. Expressed 2-5A synthetase genes and pseudogenes in the marine sponge Geodia barretti. Gene 2011; 478:42-9. [PMID: 21272622 DOI: 10.1016/j.gene.2011.01.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 01/13/2011] [Accepted: 01/14/2011] [Indexed: 11/26/2022]
Abstract
The 2',5'-oligoadenylate synthetases (2-5A synthetases, OAS) form a family of proteins presented in many branches of Metazoa. The phylum Porifera (sponges) contains OAS proteins which are different from those in vertebrates and form a distinct OAS subfamily. In turn, OAS proteins from different genera of Demospongia show rather low similarities in their primary structures. To ascertain divergence of the OAS genes within a particular sponge genus, we identified the OAS genes from the marine sponge Geodia barretti and compared them with those from another member of the genus Geodia, Geodia cydonium. The identity and similarity of the OAS sequences found in G. barretti with those from G. cydonium were considerably higher than identities and similarities compared with those from other sponges, 75% and 85% versus 27-30% and 42-47%, respectively. We also established the presence of a transcriptionally active polymorphic OAS pseudogene in the genome of G. barretti. The transcripts of the OAS pseudogene(s) lack several internal exons encoding necessary motifs for OAS enzymatic activity. The maintenance and further diversification of OAS gene(s) and pseudogene(s) suggest the prevalence of gene duplication events over the loss of gene duplicates in Geodia genomes during the evolution.
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Affiliation(s)
- Kerli Vallmann
- Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
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