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Dan Y, Yang L, Zhang H, Ren Y, He H, Yang F, Zhu J, Xiang H. The orf virus 129 protein can inhibit immune responses by interacting with host complement C1q binding protein in goat turbinate bone cells. Vet Microbiol 2023; 283:109782. [PMID: 37270925 DOI: 10.1016/j.vetmic.2023.109782] [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: 10/23/2022] [Revised: 05/19/2023] [Accepted: 05/22/2023] [Indexed: 06/06/2023]
Abstract
OBJECTIVE Contagious ecthyma is a severe and highly contagious disease caused by an orf virus (ORFV). The virus is responsible for substantial economic losses in the goat industry and threatens humans. We previously determined the role of ORFV129 protein, one of the five ankyrin-repeat proteins coded by the orf genome, in suppressing the transcription of pro-inflammatory cytokines IL-6, IL-1β and IFN-γ. In the present study, we identified 14 cellular proteins (complement C1q binding protein [C1QBP], MCM7, EIF5A, PKM, SLC6A, TSPAN6, ATP6AP2, GPS1, MMADHC, HSPB6, SLC35B1, MTF1, P3H4, and IL15RA) that interact with ORFV129 using a yeast two-hybrid system in goat turbinate bone cells (GFTCs). The interaction between ORFV129 and (C1QBP), an immune-related protein, was confirmed using immunofluorescence co-localization and co-immunoprecipitation assays. C1QBP overexpression inhibited ORFV replication, whereas the knockdown of C1QBP promoted ORFV replication in GFTCs. Furthermore, ORFV or ORFV129 increased C1QBP expression in GFTCs, indicated that ORFV129-C1QBP interaction might contribute to the ORFV-induced host immune process. In addition, our research showed that ORFV increased the expression of ORFV129, cytokine IL-6, IL-1β and IFN-γ. C1QBP overexpression induced IFN-γ production and reduced IL-6 and IL-1β production. Conversely, C1QBP knockdown induced IL-1β production and reduced IFN-γ and IL-1β production. Moreover, augmentation of ORFV129 expression enhanced the inhibition of the secretion of cytokines IL-6, IL-1β, and IFN-γ induced by the altered expression of C1QBP. These findings suggest different downstream pathways might be involved in regulating different cytokines induced by ORFV129 expression in GFTCs.
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Affiliation(s)
- Yixin Dan
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Lu Yang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Huanrong Zhang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Yupeng Ren
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Honghong He
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Falong Yang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Jiangjiang Zhu
- Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization Key Laboratory of Sichuan Province, Chengdu, China.
| | - Hua Xiang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China.
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2
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Dong J, Paszkowski P, Kocincova D, Ingham RJ. Complete deletion of Ectromelia virus p28 impairs virus genome replication in a mouse strain, cell type, and multiplicity of infection-dependent manner. Virus Res 2023; 323:198968. [PMID: 36244618 PMCID: PMC10194247 DOI: 10.1016/j.virusres.2022.198968] [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: 05/04/2022] [Revised: 09/23/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022]
Abstract
p28 is a poxvirus-encoded E3 ubiquitin ligase that possesses an N-terminal KilA-N domain and a C-terminal RING domain. In Ectromelia virus (ECTV), disruption of the p28 RING domain severely attenuated virulence in A strain mice, which normally succumb to ECTV infection. Moreover, this mutant virus exhibited dramatically reduced genome replication and impaired factory formation in A strain mice peritoneal macrophages (PMs) infected at high multiplicity of infection (MOI) These defects were not observed in PMs isolated from C57BL/6 mice which survive ECTV infection, demonstrating that p28 functions in a context-specific manner. To further investigate p28 function, we completely deleted the p28 gene from ECTV (ECTV-Δp28). In contrast to previous findings, we found that the ECTV-Δp28 virus exhibited severely compromised virus production and genome replication in PMs isolated from A strain mice only when infected at low MOI. This defect was minimal in bone marrow-derived macrophages and two cell lines derived from A strain mice. Furthermore, this low MOI defect in virus production was also observed in PMs isolated from the susceptible BALB/c mouse strain, but not PMs isolated from C57BL/6 mice. Taken together, our data demonstrate that the requirement for ECTV p28 to establish a productive infection depends on the MOI, the cell type, as well as the mouse strain.
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Affiliation(s)
- Jianing Dong
- Department of Medical Microbiology and Immunology and Li Ka Shing Institute of Virology, Katz Group Centre for Pharmacy and Health Research, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Patrick Paszkowski
- Department of Medical Microbiology and Immunology and Li Ka Shing Institute of Virology, Katz Group Centre for Pharmacy and Health Research, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Dana Kocincova
- Department of Medical Microbiology and Immunology and Li Ka Shing Institute of Virology, Katz Group Centre for Pharmacy and Health Research, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Robert J Ingham
- Department of Medical Microbiology and Immunology and Li Ka Shing Institute of Virology, Katz Group Centre for Pharmacy and Health Research, University of Alberta, Edmonton, AB T6G 2E1, Canada.
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Yang L, Zheng W, Xin S, Lv X, Sun Y, Xu T. microRNA-122 regulates NF-κB signaling pathway by targeting IκBα in miiuy croaker, Miichthys miiuy. FISH & SHELLFISH IMMUNOLOGY 2022; 122:345-351. [PMID: 35182723 DOI: 10.1016/j.fsi.2022.02.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/24/2022] [Accepted: 02/13/2022] [Indexed: 06/14/2023]
Abstract
The inhibitory protein IκBα plays a key role in the inflammatory process and immune response by regulating the activity of the transcription factor NF-κB. microRNA (miR) is a small non-coding RNA that can regulate many biochemical processes, such as cell growth, proliferation, and immune response. In this study, it was first predicted that IκBα is the target of miR-122 through bioinformatics, and it was confirmed by dual fluorescence experiments. Then we found that miR-122 can inhibit the expression of IκBα at the mRNA and protein levels, thereby promoting the p65-activated NF-κB pathway. It is speculated that miR-122 plays an important role in the innate immunity of teleost fish. This study will help to further understand miRNAs regulatory mechanism in teleost fish.
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Affiliation(s)
- Liyuan Yang
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Weiwei Zheng
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Shiying Xin
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Xing Lv
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Yuena Sun
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, 201306, China.
| | - Tianjun Xu
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, 201306, China.
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4
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Lant S, Maluquer de Motes C. Poxvirus Interactions with the Host Ubiquitin System. Pathogens 2021; 10:pathogens10081034. [PMID: 34451498 PMCID: PMC8399815 DOI: 10.3390/pathogens10081034] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/12/2021] [Accepted: 08/13/2021] [Indexed: 12/16/2022] Open
Abstract
The ubiquitin system has emerged as a master regulator of many, if not all, cellular functions. With its large repertoire of conjugating and ligating enzymes, the ubiquitin system holds a unique mechanism to provide selectivity and specificity in manipulating protein function. As intracellular parasites viruses have evolved to modulate the cellular environment to facilitate replication and subvert antiviral responses. Poxviruses are a large family of dsDNA viruses with large coding capacity that is used to synthetise proteins and enzymes needed for replication and morphogenesis as well as suppression of host responses. This review summarises our current knowledge on how poxvirus functions rely on the cellular ubiquitin system, and how poxviruses exploit this system to their own advantage, either facilitating uncoating and genome release and replication or rewiring ubiquitin ligases to downregulate critical antiviral factors. Whilst much remains to be known about the intricate interactions established between poxviruses and the host ubiquitin system, our knowledge has revealed crucial viral processes and important restriction factors that open novel avenues for antiviral treatment and provide fundamental insights on the biology of poxviruses and other virus families.
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Giotis ES, Laidlaw SM, Bidgood SR, Albrecht D, Burden JJ, Robey RC, Mercer J, Skinner MA. Modulation of Early Host Innate Immune Response by an Avipox Vaccine Virus' Lateral Body Protein. Biomedicines 2020; 8:E634. [PMID: 33352813 PMCID: PMC7766033 DOI: 10.3390/biomedicines8120634] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/14/2022] Open
Abstract
The avian pathogen fowlpox virus (FWPV) has been successfully used as a vaccine vector in poultry and humans, but relatively little is known about its ability to modulate host antiviral immune responses in these hosts, which are replication-permissive and nonpermissive, respectively. FWPV is highly resistant to avian type I interferon (IFN) and able to completely block the host IFN-response. Microarray screening of host IFN-regulated gene expression in cells infected with 59 different, nonessential FWPV gene knockout mutants revealed that FPV184 confers immunomodulatory capacity. We report that the FPV184-knockout virus (FWPVΔ184) induces the cellular IFN response as early as 2 h postinfection. The wild-type, uninduced phenotype can be rescued by transient expression of FPV184 in FWPVΔ184-infected cells. Ectopic expression of FPV184 inhibited polyI:C activation of the chicken IFN-β promoter and IFN-α activation of the chicken Mx1 promoter. Confocal and correlative super-resolution light and electron microscopy demonstrated that FPV184 has a functional nuclear localisation signal domain and is packaged in the lateral bodies of the virions. Taken together, these results provide a paradigm for a late poxvirus structural protein packaged in the lateral bodies, capable of suppressing IFN induction early during the next round of infection.
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Affiliation(s)
- Efstathios S. Giotis
- Section of Virology, School of Medicine, St Mary’s Campus, Imperial College, London W2 1PG, UK; (S.M.L.); (R.C.R.); (M.A.S.)
- School of Life Sciences, University of Essex, Colchester C04 3SQ, UK
| | - Stephen M. Laidlaw
- Section of Virology, School of Medicine, St Mary’s Campus, Imperial College, London W2 1PG, UK; (S.M.L.); (R.C.R.); (M.A.S.)
| | - Susanna R. Bidgood
- Medical Research Council-Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; (S.R.B.); (D.A.); (J.J.B.); (J.M.)
| | - David Albrecht
- Medical Research Council-Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; (S.R.B.); (D.A.); (J.J.B.); (J.M.)
| | - Jemima J. Burden
- Medical Research Council-Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; (S.R.B.); (D.A.); (J.J.B.); (J.M.)
| | - Rebecca C. Robey
- Section of Virology, School of Medicine, St Mary’s Campus, Imperial College, London W2 1PG, UK; (S.M.L.); (R.C.R.); (M.A.S.)
| | - Jason Mercer
- Medical Research Council-Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; (S.R.B.); (D.A.); (J.J.B.); (J.M.)
| | - Michael A. Skinner
- Section of Virology, School of Medicine, St Mary’s Campus, Imperial College, London W2 1PG, UK; (S.M.L.); (R.C.R.); (M.A.S.)
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Struzik J, Szulc-Dąbrowska L. NF-κB as an Important Factor in Optimizing Poxvirus-Based Vaccines against Viral Infections. Pathogens 2020; 9:pathogens9121001. [PMID: 33260450 PMCID: PMC7760304 DOI: 10.3390/pathogens9121001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/24/2020] [Accepted: 11/27/2020] [Indexed: 11/16/2022] Open
Abstract
Poxviruses are large dsDNA viruses that are regarded as good candidates for vaccine vectors. Because the members of the Poxviridae family encode numerous immunomodulatory proteins in their genomes, it is necessary to carry out certain modifications in poxviral candidates for vaccine vectors to improve the vaccine. Currently, several poxvirus-based vaccines targeted at viral infections are under development. One of the important aspects of the influence of poxviruses on the immune system is that they encode a large array of inhibitors of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), which is the key element of both innate and adaptive immunity. Importantly, the NF-κB transcription factor induces the mechanisms associated with adaptive immunological memory involving the activation of effector and memory T cells upon vaccination. Since poxviruses encode various NF-κB inhibitor proteins, before the use of poxviral vaccine vectors, modifications that influence NF-κB activation and consequently affect the immunogenicity of the vaccine should be carried out. This review focuses on NF-κB as an essential factor in the optimization of poxviral vaccines against viral infections.
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Gulyaeva AA, Gorbalenya AE. A nidovirus perspective on SARS-CoV-2. Biochem Biophys Res Commun 2020; 538:24-34. [PMID: 33413979 PMCID: PMC7664520 DOI: 10.1016/j.bbrc.2020.11.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 02/06/2023]
Abstract
Two pandemics of respiratory distress diseases associated with zoonotic introductions of the species Severe acute respiratory syndrome-related coronavirus in the human population during 21st century raised unprecedented interest in coronavirus research and assigned it unseen urgency. The two viruses responsible for the outbreaks, SARS-CoV and SARS-CoV-2, respectively, are in the spotlight, and SARS-CoV-2 is the focus of the current fast-paced research. Its foundation was laid down by studies of many corona- and related viruses that collectively form the vast order Nidovirales. Comparative genomics of nidoviruses played a key role in this advancement over more than 30 years. It facilitated the transfer of knowledge from characterized to newly identified viruses, including SARS-CoV and SARS-CoV-2, as well as contributed to the dissection of the nidovirus proteome and identification of patterns of variations between different taxonomic groups, from species to families. This review revisits selected cases of protein conservation and variation that define nidoviruses, illustrates the remarkable plasticity of the proteome during nidovirus adaptation, and asks questions at the interface of the proteome and processes that are vital for nidovirus reproduction and could inform the ongoing research of SARS-CoV-2.
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Affiliation(s)
- Anastasia A Gulyaeva
- Department of Medical Microbiology, Leiden University Medical Center, 2300 RC, Leiden, the Netherlands
| | - Alexander E Gorbalenya
- Department of Medical Microbiology, Leiden University Medical Center, 2300 RC, Leiden, the Netherlands; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119899, Moscow, Russia.
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8
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Coffman KA, Burke GR. Genomic analysis reveals an exogenous viral symbiont with dual functionality in parasitoid wasps and their hosts. PLoS Pathog 2020; 16:e1009069. [PMID: 33253317 PMCID: PMC7728225 DOI: 10.1371/journal.ppat.1009069] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 12/10/2020] [Accepted: 10/15/2020] [Indexed: 02/07/2023] Open
Abstract
Insects are known to host a wide variety of beneficial microbes that are fundamental to many aspects of their biology and have substantially shaped their evolution. Notably, parasitoid wasps have repeatedly evolved beneficial associations with viruses that enable developing wasps to survive as parasites that feed from other insects. Ongoing genomic sequencing efforts have revealed that most of these virus-derived entities are fully integrated into the genomes of parasitoid wasp lineages, representing endogenous viral elements (EVEs) that retain the ability to produce virus or virus-like particles within wasp reproductive tissues. All documented parasitoid EVEs have undergone similar genomic rearrangements compared to their viral ancestors characterized by viral genes scattered across wasp genomes and specific viral gene losses. The recurrent presence of viral endogenization and genomic reorganization in beneficial virus systems identified to date suggest that these features are crucial to forming heritable alliances between parasitoid wasps and viruses. Here, our genomic characterization of a mutualistic poxvirus associated with the wasp Diachasmimorpha longicaudata, known as Diachasmimorpha longicaudata entomopoxvirus (DlEPV), has uncovered the first instance of beneficial virus evolution that does not conform to the genomic architecture shared by parasitoid EVEs with which it displays evolutionary convergence. Rather, DlEPV retains the exogenous viral genome of its poxvirus ancestor and the majority of conserved poxvirus core genes. Additional comparative analyses indicate that DlEPV is related to a fly pathogen and contains a novel gene expansion that may be adaptive to its symbiotic role. Finally, differential expression analysis during virus replication in wasps and fly hosts demonstrates a unique mechanism of functional partitioning that allows DlEPV to persist within and provide benefit to its parasitoid wasp host.
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Affiliation(s)
- Kelsey A. Coffman
- Department of Entomology, University of Georgia, Athens, Georgia, United States of America
| | - Gaelen R. Burke
- Department of Entomology, University of Georgia, Athens, Georgia, United States of America
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Deeg CM, Zimmer MM, George EE, Husnik F, Keeling PJ, Suttle CA. Chromulinavorax destructans, a pathogen of microzooplankton that provides a window into the enigmatic candidate phylum Dependentiae. PLoS Pathog 2019; 15:e1007801. [PMID: 31150530 PMCID: PMC6561590 DOI: 10.1371/journal.ppat.1007801] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/12/2019] [Accepted: 04/30/2019] [Indexed: 11/25/2022] Open
Abstract
Members of the major candidate phylum Dependentiae (a.k.a. TM6) are widespread across diverse environments from showerheads to peat bogs; yet, with the exception of two isolates infecting amoebae, they are only known from metagenomic data. The limited knowledge of their biology indicates that they have a long evolutionary history of parasitism. Here, we present Chromulinavorax destructans (Strain SeV1) the first isolate of this phylum to infect a representative from a widespread and ecologically significant group of heterotrophic flagellates, the microzooplankter Spumella elongata (Strain CCAP 955/1). Chromulinavorax destructans has a reduced 1.2 Mb genome that is so specialized for infection that it shows no evidence of complete metabolic pathways, but encodes an extensive transporter system for importing nutrients and energy in the form of ATP from the host. Its replication causes extensive reorganization and expansion of the mitochondrion, effectively surrounding the pathogen, consistent with its dependency on the host for energy. Nearly half (44%) of the inferred proteins contain signal sequences for secretion, including many without recognizable similarity to proteins of known function, as well as 98 copies of proteins with an ankyrin-repeat domain; ankyrin-repeats are known effectors of host modulation, suggesting the presence of an extensive host-manipulation apparatus. These observations help to cement members of this phylum as widespread and diverse parasites infecting a broad range of eukaryotic microbes. Little is known about the biology of bacteria in the candidate phylum Dependentiae, despite being widespread in nature. Here, we describe a novel isolate of this phylum, Chromulinavorax destructans, which infects an abundant aquatic predatory protist, Spumella elongata. Chromulinavorax destructans is an obligate intracellular parasite, forgoes binary fission and replicates surrounded by the host mitochondrion. The genome of C. destructans encodes no detectable complete metabolic pathways and instead contains extensive transporter systems to import metabolites and even energy in the form of ATP from the host. We also found a surprising number of genes in the C. destructans genome encoding putative host modifying proteins that might be responsible for the extensive host reorganization. Phylogenetic analysis showed that C. destructans is distantly related to intracellular pathogens and symbionts of unrelated amoebae. Hence, Chromulinavorax destructans provides new insights into the biology of a widespread but largely unknown phylum of bacteria. These results imply that members of the Dependentiae are pathogens of diverse aquatic protists and are therefore likely important players in aquatic ecosystems.
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Affiliation(s)
- Christoph M. Deeg
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Matthias M. Zimmer
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada
| | - Emma E. George
- Department of Botany, University of British Columbia, Vancouver, Canada
| | - Filip Husnik
- Department of Botany, University of British Columbia, Vancouver, Canada
| | | | - Curtis A. Suttle
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada
- Department of Botany, University of British Columbia, Vancouver, Canada
- Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, Canada
- * E-mail:
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Fusade-Boyer M, Dupré G, Bessière P, Khiar S, Quentin-Froignant C, Beck C, Lecollinet S, Rameix-Welti MA, Eléouët JF, Tangy F, Lajoie B, Bertagnoli S, Vidalain PO, Gallardo F, Volmer R. Evaluation of the Antiviral Activity of Sephin1 Treatment and Its Consequences on eIF2α Phosphorylation in Response to Viral Infections. Front Immunol 2019; 10:134. [PMID: 30809223 PMCID: PMC6379315 DOI: 10.3389/fimmu.2019.00134] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/16/2019] [Indexed: 12/27/2022] Open
Abstract
The guanabenz derivative Sephin1 has recently been proposed to increase the levels of translation initiation factor 2 (eIF2α) phosphorylation by inhibiting dephosphorylation by the protein phosphatase 1-GADD34 (PPP1R15A) complex. As phosphorylation of eIF2α by protein kinase R (PKR) is a prominent cellular antiviral pathway, we evaluated the consequences of Sephin1 treatment on virus replication. Our results provide evidence that Sephin1 downregulates replication of human respiratory syncytial virus, measles virus, human adenovirus 5 virus, human enterovirus D68, human cytomegalovirus, and rabbit myxoma virus. However, Sephin1 proved to be inactive against influenza virus, as well as against Japanese encephalitis virus. Sephin1 increased the levels of phosphorylated eIF2α in cells exposed to a PKR agonist. By contrast, in virus-infected cells, the levels of phosphorylated eIF2α did not always correlate with the inhibition of virus replication by Sephin1. This work identifies Sephin1 as an antiviral molecule in cell culture against RNA, as well as DNA viruses belonging to phylogenetically distant families.
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Affiliation(s)
| | - Gabriel Dupré
- Université de Toulouse, ENVT, INRA, UMR 1225, Toulouse, France
| | - Pierre Bessière
- Université de Toulouse, ENVT, INRA, UMR 1225, Toulouse, France
| | - Samira Khiar
- Viral Genomics and Vaccination Unit, CNRS UMR-3569, Institut Pasteur, Paris, France
| | - Charlotte Quentin-Froignant
- Université de Toulouse, ENVT, INRA, UMR 1225, Toulouse, France.,NeoVirTech SAS, Institute for Advanced Life Science Technology, Toulouse, France
| | - Cécile Beck
- UMR 1161 Virology, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, ANSES Animal Health Laboratory, EURL for Equine Diseases, Maisons-Alfort, France
| | - Sylvie Lecollinet
- UMR 1161 Virology, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, ANSES Animal Health Laboratory, EURL for Equine Diseases, Maisons-Alfort, France
| | - Marie-Anne Rameix-Welti
- UMR INSERM U1173 2I, UFR des Sciences de la Santé Simone Veil-UVSQ, Montigny-le-Bretonneux, France.,AP-HP, Laboratoire de Microbiologie, Hôpital Ambroise Paré, Boulogne-Billancourt, France
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Frédéric Tangy
- Viral Genomics and Vaccination Unit, CNRS UMR-3569, Institut Pasteur, Paris, France
| | - Barbora Lajoie
- Laboratoire de Génie Chimique CNRS, INPT, UPS Université de Toulouse III, Faculté des Sciences Pharmaceutiques, Toulouse, France
| | | | - Pierre-Olivier Vidalain
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Equipe Chimie & Biologie, Modélisation et Immunologie pour la Thérapie, CNRS UMR 8601, Université Paris Descartes, Paris, France
| | - Franck Gallardo
- NeoVirTech SAS, Institute for Advanced Life Science Technology, Toulouse, France
| | - Romain Volmer
- Université de Toulouse, ENVT, INRA, UMR 1225, Toulouse, France
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Saberi A, Gulyaeva AA, Brubacher JL, Newmark PA, Gorbalenya AE. A planarian nidovirus expands the limits of RNA genome size. PLoS Pathog 2018; 14:e1007314. [PMID: 30383829 PMCID: PMC6211748 DOI: 10.1371/journal.ppat.1007314] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 09/02/2018] [Indexed: 12/28/2022] Open
Abstract
RNA viruses are the only known RNA-protein (RNP) entities capable of autonomous replication (albeit within a permissive host environment). A 33.5 kilobase (kb) nidovirus has been considered close to the upper size limit for such entities; conversely, the minimal cellular DNA genome is in the 100–300 kb range. This large difference presents a daunting gap for the transition from primordial RNP to contemporary DNA-RNP-based life. Whether or not RNA viruses represent transitional steps towards DNA-based life, studies of larger RNA viruses advance our understanding of the size constraints on RNP entities and the role of genome size in virus adaptation. For example, emergence of the largest previously known RNA genomes (20–34 kb in positive-stranded nidoviruses, including coronaviruses) is associated with the acquisition of a proofreading exoribonuclease (ExoN) encoded in the open reading frame 1b (ORF1b) in a monophyletic subset of nidoviruses. However, apparent constraints on the size of ORF1b, which encodes this and other key replicative enzymes, have been hypothesized to limit further expansion of these viral RNA genomes. Here, we characterize a novel nidovirus (planarian secretory cell nidovirus; PSCNV) whose disproportionately large ORF1b-like region including unannotated domains, and overall 41.1-kb genome, substantially extend the presumed limits on RNA genome size. This genome encodes a predicted 13,556-aa polyprotein in an unconventional single ORF, yet retains canonical nidoviral genome organization and expression, as well as key replicative domains. These domains may include functionally relevant substitutions rarely or never before observed in highly conserved sites of RdRp, NiRAN, ExoN and 3CLpro. Our evolutionary analysis suggests that PSCNV diverged early from multi-ORF nidoviruses, and acquired additional genes, including those typical of large DNA viruses or hosts, e.g. Ankyrin and Fibronectin type II, which might modulate virus-host interactions. PSCNV's greatly expanded genome, proteomic complexity, and unique features–impressive in themselves–attest to the likelihood of still-larger RNA genomes awaiting discovery. RNA viruses are the only known RNA-protein (RNP) entities capable of autonomous replication. The upper genome size for such entities was assumed to be <35 kb; conversely, the minimal cellular DNA genome is in the 100–300 kilobase (kb) range. This large difference presents a daunting gap for the proposed evolution of contemporary DNA-RNP-based life from primordial RNP entities. Here, we describe a nidovirus from planarians, named planarian secretory cell nidovirus (PSCNV), whose 41.1 kb genome is 23% larger than any riboviral genome yet discovered. This increase is nearly equivalent in size to the entire poliovirus genome, and it equips PSCNV with an unprecedented extra coding capacity to adapt. PSCNV has broken apparent constraints on the size of the genomic subregion that encodes core replication machinery in other nidoviruses, including coronaviruses, and has acquired genes not previously observed in RNA viruses. This virus challenges and advances our understanding of the limits to RNA genome size.
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Affiliation(s)
- Amir Saberi
- Howard Hughes Medical Institute, Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States of America
| | - Anastasia A. Gulyaeva
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - John L. Brubacher
- Department of Biology, Canadian Mennonite University, Winnipeg, Canada
| | - Phillip A. Newmark
- Howard Hughes Medical Institute, Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States of America
- * E-mail: (PAN); (AEG)
| | - Alexander E. Gorbalenya
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
- * E-mail: (PAN); (AEG)
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12
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Evans SM, Rodino KG, Adcox HE, Carlyon JA. Orientia tsutsugamushi uses two Ank effectors to modulate NF-κB p65 nuclear transport and inhibit NF-κB transcriptional activation. PLoS Pathog 2018; 14:e1007023. [PMID: 29734393 PMCID: PMC5957444 DOI: 10.1371/journal.ppat.1007023] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 05/17/2018] [Accepted: 04/11/2018] [Indexed: 01/05/2023] Open
Abstract
Orientia tsutsugamushi causes scrub typhus, a potentially fatal infection that threatens over one billion people. Nuclear translocation of the transcription factor, NF-κB, is the central initiating cellular event in the antimicrobial response. Here, we report that NF-κB p65 nuclear accumulation and NF-κB-dependent transcription are inhibited in O. tsutsugamushi infected HeLa cells and/or primary macrophages, even in the presence of TNFα. The bacterium modulates p65 subcellular localization by neither degrading it nor inhibiting IκBα degradation. Rather, it exploits host exportin 1 to mediate p65 nuclear export, as this phenomenon is leptomycin B-sensitive. O. tsutsugamushi antagonizes NF-κB-activated transcription even when exportin 1 is inhibited and NF-κB consequently remains in the nucleus. Two ankyrin repeat-containing effectors (Anks), Ank1 and Ank6, each of which possess a C-terminal F-box and exhibit 58.5% amino acid identity, are linked to the pathogen's ability to modulate NF-κB. When ectopically expressed, both translocate to the nucleus, abrogate NF-κB-activated transcription in an exportin 1-independent manner, and pronouncedly reduce TNFα-induced p65 nuclear levels by exportin 1-dependent means. Flag-tagged Ank 1 and Ank6 co-immunoprecipitate p65 and exportin 1. Both also bind importin β1, a host protein that is essential for the classical nuclear import pathway. Importazole, which blocks importin β1 activity, abrogates Ank1 and Ank6 nuclear translocation. The Ank1 and Ank6 regions that bind importin β1 also mediate their transport into the nucleus. Yet, these regions are distinct from those that bind p65/exportin 1. The Ank1 and Ank6 F-box and the region that lies between it and the ankyrin repeat domain are essential for blocking p65 nuclear accumulation. These data reveal a novel mechanism by which O. tsutsugamushi modulates the activity and nuclear transport of NF-κB p65 and identify the first microbial proteins that co-opt both importin β1 and exportin 1 to antagonize a critical arm of the antimicrobial response.
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Affiliation(s)
- Sean M. Evans
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Kyle G. Rodino
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Haley E. Adcox
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Jason A. Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
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13
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Deeg CM, Chow CET, Suttle CA. The kinetoplastid-infecting Bodo saltans virus (BsV), a window into the most abundant giant viruses in the sea. eLife 2018; 7:33014. [PMID: 29582753 PMCID: PMC5871332 DOI: 10.7554/elife.33014] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 02/22/2018] [Indexed: 01/24/2023] Open
Abstract
Giant viruses are ecologically important players in aquatic ecosystems that have challenged concepts of what constitutes a virus. Herein, we present the giant Bodo saltans virus (BsV), the first characterized representative of the most abundant group of giant viruses in ocean metagenomes, and the first isolate of a klosneuvirus, a subgroup of the Mimiviridae proposed from metagenomic data. BsV infects an ecologically important microzooplankton, the kinetoplastid Bodo saltans. Its 1.39 Mb genome encodes 1227 predicted ORFs, including a complex replication machinery. Yet, much of its translational apparatus has been lost, including all tRNAs. Essential genes are invaded by homing endonuclease-encoding self-splicing introns that may defend against competing viruses. Putative anti-host factors show extensive gene duplication via a genomic accordion indicating an ongoing evolutionary arms race and highlighting the rapid evolution and genomic plasticity that has led to genome gigantism and the enigma that is giant viruses.
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Affiliation(s)
- Christoph M Deeg
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Cheryl-Emiliane T Chow
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada
| | - Curtis A Suttle
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada.,Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada.,Department of Botany, University of British Columbia, Vancouver, Canada.,Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, Canada
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14
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Myxoma Virus M083 Is a Virulence Factor Which Mediates Systemic Dissemination. J Virol 2018; 92:JVI.02186-17. [PMID: 29343569 DOI: 10.1128/jvi.02186-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 01/09/2018] [Indexed: 11/20/2022] Open
Abstract
Poxviruses are large, DNA viruses whose protein capsid is surrounded by one or more lipid envelopes. Embedded into these lipid envelopes are three conserved viral proteins which are thought to mediate binding of virions to target cells. While the function of these proteins has been studied in vitro, their specific roles during the pathogenesis of poxviral disease remain largely unclear. Here we present data demonstrating that the putative chondroitin binding protein M083 from the leporipoxvirus myxoma virus is a significant virulence factor during infection of susceptible Oryctolagus rabbits. Removal of M083 results in a reduced capacity of virus to spread beyond the regional lymph nodes and completely eliminates infection-mediated mortality. In vitro, removal of M083 results in only minor intracellular replication defects but causes a significant reduction in the ability of myxoma virus to spread from infected epithelial cells onto primary lymphocytes. We hypothesize that the physiological role of M083 is therefore to mediate the spread of myxoma virus onto rabbit lymphocytes, allowing these cells to disseminate virus throughout infected rabbits.IMPORTANCE Poxviruses represent both a class of human pathogens and potential therapeutic agents for the treatment of human malignancy. Understanding the basic biology of these agents is therefore significant to human health in a variety of ways. While the mechanisms mediating poxviral binding have been well studied in vitro, how these mechanisms impact poxviral pathogenesis in vivo remains unclear. The current study advances our understanding of how poxviral binding impacts viral pathogenesis by demonstrating that the putative chondroitin binding protein M083 plays a critical role during the pathogenesis of myxoma virus in susceptible Oryctolagus rabbits by impacting viral dissemination through changes in the transfer of virions onto primary splenocytes.
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15
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Nagendraprabhu P, Khatiwada S, Chaulagain S, Delhon G, Rock DL. A parapoxviral virion protein targets the retinoblastoma protein to inhibit NF-κB signaling. PLoS Pathog 2017; 13:e1006779. [PMID: 29244863 PMCID: PMC5747488 DOI: 10.1371/journal.ppat.1006779] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 12/29/2017] [Accepted: 11/28/2017] [Indexed: 12/14/2022] Open
Abstract
Poxviruses have evolved multiple strategies to subvert signaling by Nuclear Factor κB (NF-κB), a crucial regulator of host innate immune responses. Here, we describe an orf virus (ORFV) virion-associated protein, ORFV119, which inhibits NF-κB signaling very early in infection (≤ 30 min post infection). ORFV119 NF-κB inhibitory activity was found unimpaired upon translation inhibition, suggesting that virion ORFV119 alone is responsible for early interference in signaling. A C-terminal LxCxE motif in ORFV119 enabled the protein to interact with the retinoblastoma protein (pRb) a multifunctional protein best known for its tumor suppressor activity. Notably, experiments using a recombinant virus containing an ORFV119 mutation which abrogates its interaction with pRb together with experiments performed in cells lacking or with reduced pRb levels indicate that ORFV119 mediated inhibition of NF-κB signaling is largely pRb dependent. ORFV119 was shown to inhibit IKK complex activation early in infection. Consistent with IKK inhibition, ORFV119 also interacted with TNF receptor associated factor 2 (TRAF2), an adaptor protein recruited to signaling complexes upstream of IKK in infected cells. ORFV119-TRAF2 interaction was enhanced in the presence of pRb, suggesting that ORFV119-pRb complex is required for efficient interaction with TRAF2. Additionally, transient expression of ORFV119 in uninfected cells was sufficient to inhibit TNFα-induced IKK activation and NF-κB signaling, indicating that no other viral proteins are required for the effect. Infection of sheep with ORFV lacking the ORFV119 gene led to attenuated disease phenotype, indicating that ORFV119 contributes to virulence in the natural host. ORFV119 represents the first poxviral protein to interfere with NF-κB signaling through interaction with pRb.
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Affiliation(s)
- Ponnuraj Nagendraprabhu
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana- Champaign, Urbana, IL, United States of America
| | - Sushil Khatiwada
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana- Champaign, Urbana, IL, United States of America
| | - Sabal Chaulagain
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana- Champaign, Urbana, IL, United States of America
| | - Gustavo Delhon
- School of Veterinary and Biomedical Sciences, Center for Virology, University of Nebraska-Lincoln, Lincoln, NE, United States of America
- * E-mail: (GD); (DLR)
| | - Daniel L. Rock
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana- Champaign, Urbana, IL, United States of America
- * E-mail: (GD); (DLR)
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16
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Khatiwada S, Delhon G, Nagendraprabhu P, Chaulagain S, Luo S, Diel DG, Flores EF, Rock DL. A parapoxviral virion protein inhibits NF-κB signaling early in infection. PLoS Pathog 2017; 13:e1006561. [PMID: 28787456 PMCID: PMC5560748 DOI: 10.1371/journal.ppat.1006561] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 08/17/2017] [Accepted: 07/31/2017] [Indexed: 12/16/2022] Open
Abstract
Poxviruses have evolved unique proteins and mechanisms to counteract the nuclear factor κB (NF-κB) signaling pathway, which is an essential regulatory pathway of host innate immune responses. Here, we describe a NF-κB inhibitory virion protein of orf virus (ORFV), ORFV073, which functions very early in infected cells. Infection with ORFV073 gene deletion virus (OV-IA82Δ073) led to increased accumulation of NF-κB essential modulator (NEMO), marked phosphorylation of IκB kinase (IKK) subunits IKKα and IKKβ, IκBα and NF-κB subunit p65 (NF-κB-p65), and to early nuclear translocation of NF-κB-p65 in virus-infected cells (≤ 30 min post infection). Expression of ORFV073 alone was sufficient to inhibit TNFα induced activation of the NF-κB signaling in uninfected cells. Consistent with observed inhibition of IKK complex activation, ORFV073 interacted with the regulatory subunit of the IKK complex NEMO. Infection of sheep with OV-IA82Δ073 led to virus attenuation, indicating that ORFV073 is a virulence determinant in the natural host. Notably, ORFV073 represents the first poxviral virion-associated NF-κB inhibitor described, highlighting the significance of viral inhibition of NF-κB signaling very early in infection.
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Affiliation(s)
- Sushil Khatiwada
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Gustavo Delhon
- School of Veterinary Medicine and Biomedical Science, Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Ponnuraj Nagendraprabhu
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Sabal Chaulagain
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Shuhong Luo
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Diego G. Diel
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Eduardo F. Flores
- Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - Daniel L. Rock
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
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17
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Braun C, Thürmer A, Daniel R, Schultz AK, Bulla I, Schirrmeier H, Mayer D, Neubert A, Czerny CP. Genetic Variability of Myxoma Virus Genomes. J Virol 2017; 91:e01570-16. [PMID: 27903800 PMCID: PMC5286896 DOI: 10.1128/jvi.01570-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/18/2016] [Indexed: 12/12/2022] Open
Abstract
Myxomatosis is a recurrent problem on rabbit farms throughout Europe despite the success of vaccines. To identify gene variations of field and vaccine strains that may be responsible for changes in virulence, immunomodulation, and immunoprotection, the genomes of 6 myxoma virus (MYXV) strains were sequenced: German field isolates Munich-1, FLI-H, 2604, and 3207; vaccine strain MAV; and challenge strain ZA. The analyzed genomes ranged from 147.6 kb (strain MAV) to 161.8 kb (strain 3207). All sequences were affected by several mutations, covering 24 to 93 open reading frames (ORFs) and resulted in amino acid substitutions, insertions, or deletions. Only strains Munich-1 and MAV revealed the deletion of 10 ORFs (M007L to M015L) and 11 ORFs (M007L to M008.1L and M149R to M008.1R), respectively. Major differences were observed in the 27 immunomodulatory proteins encoded by MYXV. Compared to the reference strain Lausanne, strains FLI-H, 2604, 3207, and ZA showed the highest amino acid identity (>98.4%). In strains Munich-1 and MAV, deletion of 5 and 10 ORFs, respectively, was observed, encoding immunomodulatory proteins with ankyrin repeats or members of the family of serine protease inhibitors. Furthermore, putative immunodominant surface proteins with homology to vaccinia virus (VACV) were investigated in the sequenced strains. Only strain MAV revealed above-average frequencies of amino acid substitutions and frameshift mutations. Finally, we performed recombination analysis and found signs of recombination in vaccine strain MAV. Phylogenetic analysis showed a close relationship of strain MAV and the MSW strain of Californian MYXV. However, in a challenge model, strain MAV provided full protection against lethal challenges with strain ZA. IMPORTANCE Myxoma virus (MYXV) is pathogenic for European rabbits and two North American species. Due to sophisticated strategies in immune evasion and oncolysis, MYXV is an important model virus for immunological and pathological research. In its natural hosts, MYXV causes a benign infection, whereas in European rabbits, it causes the lethal disease myxomatosis. Since the introduction of MYXV into Australia and Europe for the biological control of European rabbits in the 1950s, a coevolution of host and pathogen has started, selecting for attenuated virus strains and increased resistance in rabbits. Evolution of viruses is a continuous process and influences the protective potential of vaccines. In our analyses, we sequenced 6 MYXV field, challenge, and vaccine strains. We focused on genes encoding proteins involved in virulence, host range, immunomodulation, and envelope composition. Genes affected most by mutations play a role in immunomodulation. However, attenuation cannot be linked to individual mutations or gene disruptions.
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Affiliation(s)
- Christoph Braun
- Department of Animal Sciences, Institute of Veterinary Medicine, Division of Microbiology and Animal Hygiene, Faculty of Agricultural Sciences, Georg August University Göttingen, Göttingen, Germany
| | - Andrea Thürmer
- Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg August University, Göttingen, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg August University, Göttingen, Germany
| | - Anne-Kathrin Schultz
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg August University, Göttingen, Germany
| | - Ingo Bulla
- Institute for Mathematics and Informatics, University of Greifswald, Greifswald, Germany
| | - Horst Schirrmeier
- Institute of Diagnostic Virology, Friedrich Loeffler Institut, Greifswald-Insel Riems, Germany
| | | | | | - Claus-Peter Czerny
- Department of Animal Sciences, Institute of Veterinary Medicine, Division of Microbiology and Animal Hygiene, Faculty of Agricultural Sciences, Georg August University Göttingen, Göttingen, Germany
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Bravo Cruz AG, Shisler JL. Vaccinia virus K1 ankyrin repeat protein inhibits NF-κB activation by preventing RelA acetylation. J Gen Virol 2016; 97:2691-2702. [DOI: 10.1099/jgv.0.000576] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Ariana G. Bravo Cruz
- Department of Microbiology, University of Illinois, 601 S. Goodwin Avenue, Urbana, IL 61801, USA
| | - Joanna L. Shisler
- Department of Microbiology, University of Illinois, 601 S. Goodwin Avenue, Urbana, IL 61801, USA
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19
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Infection of goats with goatpox virus triggers host antiviral defense through activation of innate immune signaling. Res Vet Sci 2015; 104:40-9. [PMID: 26850535 DOI: 10.1016/j.rvsc.2015.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 10/19/2015] [Accepted: 11/11/2015] [Indexed: 01/05/2023]
Abstract
Goatpox, caused by goatpox virus (GTPV), is one of the most serious infectious diseases associated with high morbidity and mortality in goats. However, little is known about involvement of host innate immunity during the GTPV infection. For this, goats were experimentally infected with GTPV. The results showed that GTPV infection significantly induced mRNA expression of type I interferon (IFN)-α and IFN-β in peripheral blood lymphocytes, spleen and lung. In addition, GTPV infection enhanced expression of several inflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-18; and tumor necrosis factor-α (TNF-α). Strikingly, infection with GTPV activated signal transducers and activators of transcription 3 (STAT3), a critical cytokine signaling molecule. Interestingly, the virus infection induced expression of suppressor of cytokine signaling (SOCS)-1. Importantly, the infection resulted in an increased expression of some critical interferon-stimulated genes, such as interferon-induced transmembrane protein (IFITM) 1, IFITM3, interferon stimulated gene (ISG) 15 and ISG20. Furthermore, we found that infection with GTPV up-regulated expression of Toll-like receptor (TLR) 2 and TLR9. These results revealed that GTPV infection activated host innate immune signaling and thereby triggered antiviral innate immunity. The findings provide novel insights into complex mechanisms underlying GTPV-host interaction and pathogenesis of GTPV.
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20
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Bonamassa B, Ciccarese F, Antonio VD, Contarini A, Palù G, Alvisi G. Hepatitis C virus and host cell nuclear transport machinery: a clandestine affair. Front Microbiol 2015; 6:619. [PMID: 26150811 PMCID: PMC4472997 DOI: 10.3389/fmicb.2015.00619] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Accepted: 06/03/2015] [Indexed: 11/13/2022] Open
Abstract
There is growing evidence that factors encoded by cytoplasmic replicating viruses functionally interact with components of the nucleocytoplasmic transport apparatus. They do so either to access the cell nucleus, thus affecting genes expression, or to interfere with nuclear transport functionality, hindering host immune response. Recent studies revealed that the hepatitis C virus (HCV) makes no exception, interacting with the host cell nuclear transport machinery at two different levels. On the one hand, small amounts of both core and NS5A localize within the host cell nucleus during productive infection, modulating gene expression and signaling functions to promote persistent infection. On the other hand, HCV infection causes a profound redistribution of certain nucleoproteins to the close proximity of endoplasmic reticulum membrane-derived viral replication factories, where viral RNA amplification occurs. These nucleoporins are believed to form nuclear pore complex-like structures, as suggested by their ability to recruit nuclear localization sequence-bearing proteins. Thus, both processes are linked to virus-induced persistence and pathogenesis, representing possible targets for the development of novel anti-HCV therapeutics.
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Affiliation(s)
- Barbara Bonamassa
- Department of Molecular Medicine, University of Padua , Padua, Italy
| | | | | | - Andrea Contarini
- Department of Molecular Medicine, University of Padua , Padua, Italy
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padua , Padua, Italy
| | - Gualtiero Alvisi
- Department of Molecular Medicine, University of Padua , Padua, Italy
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21
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Kerr PJ, Liu J, Cattadori I, Ghedin E, Read AF, Holmes EC. Myxoma virus and the Leporipoxviruses: an evolutionary paradigm. Viruses 2015; 7:1020-61. [PMID: 25757062 PMCID: PMC4379559 DOI: 10.3390/v7031020] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/20/2015] [Accepted: 02/26/2015] [Indexed: 01/31/2023] Open
Abstract
Myxoma virus (MYXV) is the type species of the Leporipoxviruses, a genus of Chordopoxvirinae, double stranded DNA viruses, whose members infect leporids and squirrels, inducing cutaneous fibromas from which virus is mechanically transmitted by biting arthropods. However, in the European rabbit (Oryctolagus cuniculus), MYXV causes the lethal disease myxomatosis. The release of MYXV as a biological control for the wild European rabbit population in Australia, initiated one of the great experiments in evolution. The subsequent coevolution of MYXV and rabbits is a classic example of natural selection acting on virulence as a pathogen adapts to a novel host species. Slightly attenuated mutants of the progenitor virus were more readily transmitted by the mosquito vector because the infected rabbit survived longer, while highly attenuated viruses could be controlled by the rabbit immune response. As a consequence, moderately attenuated viruses came to dominate. This evolution of the virus was accompanied by selection for genetic resistance in the wild rabbit population, which may have created an ongoing co-evolutionary dynamic between resistance and virulence for efficient transmission. This natural experiment was repeated on a continental scale with the release of a separate strain of MYXV in France and its subsequent spread throughout Europe. The selection of attenuated strains of virus and resistant rabbits mirrored the experience in Australia in a very different environment, albeit with somewhat different rates. Genome sequencing of the progenitor virus and the early radiation, as well as those from the 1990s in Australia and Europe, has shown that although MYXV evolved at high rates there was no conserved route to attenuation or back to virulence. In contrast, it seems that these relatively large viral genomes have the flexibility for multiple pathways that converge on a similar phenotype.
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Affiliation(s)
- Peter J Kerr
- CSIRO Biosecurity Flagship, Black Mountain Laboratories, Clunies Ross Street, Acton, ACT 2601, Australia.
| | - June Liu
- CSIRO Biosecurity Flagship, Black Mountain Laboratories, Clunies Ross Street, Acton, ACT 2601, Australia.
| | - Isabella Cattadori
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Elodie Ghedin
- Center for Genomics and Systems Biology, Department of Biology and Global Institute of Public Health, New York University, New York, NY 10003, USA.
| | - Andrew F Read
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Edward C Holmes
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Biological Sciences, and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
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22
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Herbert MH, Squire CJ, Mercer AA. Poxviral ankyrin proteins. Viruses 2015; 7:709-38. [PMID: 25690795 PMCID: PMC4353913 DOI: 10.3390/v7020709] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/05/2015] [Accepted: 02/09/2015] [Indexed: 02/08/2023] Open
Abstract
Multiple repeats of the ankyrin motif (ANK) are ubiquitous throughout the kingdoms of life but are absent from most viruses. The main exception to this is the poxvirus family, and specifically the chordopoxviruses, with ANK repeat proteins present in all but three species from separate genera. The poxviral ANK repeat proteins belong to distinct orthologue groups spread over different species, and align well with the phylogeny of their genera. This distribution throughout the chordopoxviruses indicates these proteins were present in an ancestral vertebrate poxvirus, and have since undergone numerous duplication events. Most poxviral ANK repeat proteins contain an unusual topology of multiple ANK motifs starting at the N-terminus with a C-terminal poxviral homologue of the cellular F-box enabling interaction with the cellular SCF ubiquitin ligase complex. The subtle variations between ANK repeat proteins of individual poxviruses suggest an array of different substrates may be bound by these protein-protein interaction domains and, via the F-box, potentially directed to cellular ubiquitination pathways and possible degradation. Known interaction partners of several of these proteins indicate that the NF-κB coordinated anti-viral response is a key target, whilst some poxviral ANK repeat domains also have an F-box independent affect on viral host-range.
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Affiliation(s)
- Michael H Herbert
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand.
| | - Christopher J Squire
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand.
| | - Andrew A Mercer
- Virus Research Unit, Department of Microbiology and Immunology, University of Otago, Dunedin 9016, New Zealand.
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Lamb SA, Rahman MM, McFadden G. Recombinant myxoma virus lacking all poxvirus ankyrin-repeat proteins stimulates multiple cellular anti-viral pathways and exhibits a severe decrease in virulence. Virology 2014; 464-465:134-145. [PMID: 25068401 DOI: 10.1016/j.virol.2014.06.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/01/2014] [Accepted: 06/17/2014] [Indexed: 12/31/2022]
Abstract
Although the production of single gene knockout viruses is a useful strategy to study viral gene functions, the redundancy of many host interactive genes within a complex viral genome can obscure their collective functions. In this study, a rabbit-specific poxvirus, myxoma virus (MYXV), was genetically altered to disrupt multiple members of the poxviral ankyrin-repeat (ANK-R) protein superfamily, M-T5, M148, M149 and M150. A particularly robust activation of the NF-κB pathway was observed in A549 cells following infection with the complete ANK-R knockout (vMyx-ANKsKO). Also, an increased release of IL-6 was only observed upon infection with vMyx-ANKsKO. In virus-infected rabbit studies, vMyx-ANKsKO was the most extensively attenuated and produced the smallest primary lesion of all ANK-R mutant constructs. This study provides the first insights into the shared functions of the poxviral ANK-R protein superfamily in vitro and in vivo.
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Affiliation(s)
- Stephanie A Lamb
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, 1600 SW Archer Road, PO Box 100266, Gainesville FL 32610, USA
| | - Masmudur M Rahman
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, 1600 SW Archer Road, PO Box 100266, Gainesville FL 32610, USA
| | - Grant McFadden
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, 1600 SW Archer Road, PO Box 100266, Gainesville FL 32610, USA
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24
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Brady G, Bowie AG. Innate immune activation of NFκB and its antagonism by poxviruses. Cytokine Growth Factor Rev 2014; 25:611-20. [PMID: 25081317 DOI: 10.1016/j.cytogfr.2014.07.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/03/2014] [Indexed: 12/18/2022]
Abstract
In recent years there has been an acceleration of discovery in the field of innate anti-viral immunity to the point that many of the key events in early virus sensing and the discrete anti-viral responses they trigger have been elucidated in detail. In particular, pattern recognition receptors (PRRs) that detect viruses at the plasma membrane, in endosomes, and within the cytosol have been characterized. Upon stimulation by viruses, most of these PRRs trigger signal transduction pathways culminating in NFκB activation. NFκB contributes both to type I interferon induction, and to production of pro-inflammatory cytokines from infected cells. Our understanding of host anti-viral innate immunity has been greatly aided by an appreciation of the ways in which poxviruses have evolved strategies to inhibit both innate sensing and effector responses. A recurring feature of poxviral immunomodulation is the apparent necessity for poxviruses to evolve multiple, non-redundant inhibitors of NFκB activation which often appear to act on the same innate signalling pathway. The reason for such apparent over-targeting of one transcription factor is not clear. Here we describe the current understanding of how host cells sense poxvirus infection to trigger signalling pathways leading to NFκB activation and pro-inflammatory cytokine induction, and the ways in which poxviruses have evolved to concisely antagonize these systems.
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Affiliation(s)
- Gareth Brady
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland.
| | - Andrew G Bowie
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland.
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25
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Lacek K, Bauer B, Bieńkowska-Szewczyk K, Rziha HJ. Orf virus (ORFV) ANK-1 protein mitochondrial localization is mediated by ankyrin repeat motifs. Virus Genes 2014; 49:68-79. [PMID: 24743940 DOI: 10.1007/s11262-014-1069-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 04/03/2014] [Indexed: 10/25/2022]
Abstract
Orf virus (ORFV) strain D1701-V, a Parapoxvirus belonging to the family Poxviridae, became attractive as a novel virus vector system that we successfully used for the generation of recombinant vaccines. Therefore, the identification of viral genes involved in host tropisms or immune modulation is of great interest, as for instance the ORFV-encoded ankyrin-repeat (AR) containing proteins. The present study shows for the first time that the ANK-1 designated gene product of ORFV126 is targeted to mitochondria of ORFV-infected and in ANK-1 transiently expressing cells. Taking advantage of ANK-1 EGFP fusion proteins and confocal fluorescence microscopy mutational and deletion analyses indicated the importance of AR8 and AR9, which may contain a novel class of mitochondria-targeting sequence (MTS) in the central to C-terminal part of this AR-containing protein. The fluorescent findings were corroborated by cell fractionation and Western blotting experiments. The presented results open the avenue for more detailed investigations on cellular binding partners and the function of ANK-1 in viral replication or virulence.
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Affiliation(s)
- Krzysztof Lacek
- Laboratory of Virus Molecular Biology, University of Gdańsk, 80-822, Gdańsk, Poland
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26
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Abstract
The transcription factor nuclear factor kappa light-chain enhancer of activated B cells (NF-κB) plays a critical role in host defense against viral infection by inducing the production of proinflammatory mediators and type I interferon. Consequently, viruses have evolved many mechanisms to block its activation. The poxvirus vaccinia virus (VACV) encodes numerous inhibitors of NF-κB activation that target multiple points in the signaling pathway. A derivative of VACV strain Copenhagen, called vv811, lacking 55 open reading frames in the left and right terminal regions of the genome was reported to still inhibit NF-κB activation downstream of tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β), suggesting the presence of one or more additional inhibitors. In this study, we constructed a recombinant vv811 lacking the recently described NF-κB inhibitor A49 (vv811ΔA49), yielding a virus that lacked all currently described inhibitors downstream of TNF-α and IL-1β. Unlike vv811, vv811ΔA49 no longer inhibited degradation of the phosphorylated inhibitor of κBα and p65 translocated into the nucleus. However, despite this translocation, vv811ΔA49 still inhibited TNF-α- and IL-1β-induced NF-κB-dependent reporter gene expression and the transcription and production of cytokines induced by these agonists. This inhibition did not require late viral gene expression. These findings indicate the presence of another inhibitor of NF-κB that is expressed early during infection and acts by a novel mechanism downstream of p65 translocation into the nucleus.
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27
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Merkel cell polyomavirus small T antigen targets the NEMO adaptor protein to disrupt inflammatory signaling. J Virol 2013; 87:13853-67. [PMID: 24109239 DOI: 10.1128/jvi.02159-13] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Merkel cell carcinoma (MCC) is a highly aggressive nonmelanoma skin cancer arising from epidermal mechanoreceptor Merkel cells. In 2008, a novel human polyomavirus, Merkel cell polyomavirus (MCPyV), was identified and is strongly implicated in MCC pathogenesis. Currently, little is known regarding the virus-host cell interactions which support virus replication and virus-induced mechanisms in cellular transformation and metastasis. Here we identify a new function of MCPyV small T antigen (ST) as an inhibitor of NF-κB-mediated transcription. This effect is due to an interaction between MCPyV ST and the NF-κB essential modulator (NEMO) adaptor protein. MCPyV ST expression inhibits IκB kinase α (IKKα)/IKKβ-mediated IκB phosphorylation, which limits translocation of the NF-κB heterodimer to the nucleus. Regulation of this process involves a previously undescribed interaction between MCPyV ST and the cellular phosphatase subunits, protein phosphatase 4C (PP4C) and/or protein phosphatase 2A (PP2A) Aβ, but not PP2A Aα. Together, these results highlight a novel function of MCPyV ST to subvert the innate immune response, allowing establishment of early or persistent infection within the host cell.
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28
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Correa RL, Bruckner FP, de Souza Cascardo R, Alfenas-Zerbini P. The Role of F-Box Proteins during Viral Infection. Int J Mol Sci 2013; 14:4030-49. [PMID: 23429191 PMCID: PMC3588083 DOI: 10.3390/ijms14024030] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/14/2012] [Accepted: 01/17/2013] [Indexed: 01/10/2023] Open
Abstract
The F-box domain is a protein structural motif of about 50 amino acids that mediates protein–protein interactions. The F-box protein is one of the four components of the SCF (SKp1, Cullin, F-box protein) complex, which mediates ubiquitination of proteins targeted for degradation by the proteasome, playing an essential role in many cellular processes. Several discoveries have been made on the use of the ubiquitin–proteasome system by viruses of several families to complete their infection cycle. On the other hand, F-box proteins can be used in the defense response by the host. This review describes the role of F-box proteins and the use of the ubiquitin–proteasome system in virus–host interactions.
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Affiliation(s)
- Régis Lopes Correa
- Department of Genetics, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-970, Brazil; E-Mails: (R.L.C.); (R.S.C.)
| | - Fernanda Prieto Bruckner
- Department of Microbiology/BIOAGRO, Federal University of Viçosa, Viçosa, MG 36570-000, Brazil; E-Mail:
| | - Renan de Souza Cascardo
- Department of Genetics, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-970, Brazil; E-Mails: (R.L.C.); (R.S.C.)
- Department of Microbiology/BIOAGRO, Federal University of Viçosa, Viçosa, MG 36570-000, Brazil; E-Mail:
| | - Poliane Alfenas-Zerbini
- Department of Microbiology/BIOAGRO, Federal University of Viçosa, Viçosa, MG 36570-000, Brazil; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +55-31-3899-2955; Fax: +55-31-3899-2864
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29
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Weber O, Mercer AA, Friebe A, Knolle P, Volk HD. Therapeutic immunomodulation using a virus--the potential of inactivated orf virus. Eur J Clin Microbiol Infect Dis 2012; 32:451-60. [PMID: 23179251 DOI: 10.1007/s10096-012-1780-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 11/07/2012] [Indexed: 12/15/2022]
Abstract
Viruses can manipulate the immune response against them by various strategies to influence immune cells, i.e. by over-activation leading to functional inactivation, bypassing antigen presentation or even suppression of effector functions. Little is known, however, about how these features of immune regulation and modulation could be used for therapeutic purposes. Reasons for this include the complexity of immune regulatory mechanisms under certain disease conditions and the risks that infections with viruses pose to human beings. The orf virus (ORFV), a member of the Parapoxvirus genus of the poxvirus family, is known as a common pathogen in sheep and goats worldwide. The inactivated ORFV, however, has been used as a preventative as well as therapeutic immunomodulator in veterinary medicine in different species. Here, we review the key results obtained in pre-clinical studies or clinical studies in veterinary medicine to characterise the therapeutic potential of inactivated ORFV. Inactivated ORFV has strong effects on cytokine secretion in mice and human immune cells, leading to an auto-regulated loop of initial up-regulation of inflammatory and Th1-related cytokines, followed by Th2-related cytokines that attenuate immunopathology. The therapeutic potential of inactivated ORFV has been recognised in several difficult-to-treat disease areas, such as chronic viral diseases, liver fibrosis or various forms of cancer. Further research will be required in order to evaluate the full beneficial potential of inactivated ORFV for therapeutic immunomodulation.
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Affiliation(s)
- O Weber
- Bayer Pharmaceuticals Global Drug Discovery, Bayer HealthCare AG, Leverkusen, Germany.
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30
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Kerr PJ, Ghedin E, DePasse JV, Fitch A, Cattadori IM, Hudson PJ, Tscharke DC, Read AF, Holmes EC. Evolutionary history and attenuation of myxoma virus on two continents. PLoS Pathog 2012; 8:e1002950. [PMID: 23055928 PMCID: PMC3464225 DOI: 10.1371/journal.ppat.1002950] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 08/22/2012] [Indexed: 01/05/2023] Open
Abstract
The attenuation of myxoma virus (MYXV) following its introduction as a biological control into the European rabbit populations of Australia and Europe is the canonical study of the evolution of virulence. However, the evolutionary genetics of this profound change in host-pathogen relationship is unknown. We describe the genome-scale evolution of MYXV covering a range of virulence grades sampled over 49 years from the parallel Australian and European epidemics, including the high-virulence progenitor strains released in the early 1950s. MYXV evolved rapidly over the sampling period, exhibiting one of the highest nucleotide substitution rates ever reported for a double-stranded DNA virus, and indicative of a relatively high mutation rate and/or a continually changing selective environment. Our comparative sequence data reveal that changes in virulence involved multiple genes, likely losses of gene function due to insertion-deletion events, and no mutations common to specific virulence grades. Hence, despite the similarity in selection pressures there are multiple genetic routes to attain either highly virulent or attenuated phenotypes in MYXV, resulting in convergence for phenotype but not genotype. The text-book example of the evolution of virulence is the attenuation of myxoma virus (MYXV) following its introduction as a biological control into the European rabbit populations of Australia and Europe in the 1950s. However, the key work on this topic, most notably by Frank Fenner and his colleagues, occurred before the availability of genome sequence data. The evolutionary genetic basis to the major changes in virulence in both the Australian and European epidemics is therefore largely unknown. We provide, for the first time, key details on the genome-wide changes that underpin this landmark example of pathogen emergence and virulence evolution. By sequencing and comparing MYXV genomes, including the original strains released in the 1950s, we show that (i) MYXV evolved rapidly in both Australia and Europe, producing one of the highest rates of evolutionary change ever recorded for a DNA virus, (ii) that changes in virulence were caused by mutations in multiple genes, often involving losses of gene function due to insertions and deletions, and that (iii) strains of the same virulence were defined by different mutations, such that both attenuated and virulent MYXV strains are produced by a variety genetic pathways, and generating convergent evolution for phenotype but not genotype.
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Affiliation(s)
- Peter J. Kerr
- CSIRO Ecosystem Sciences, Canberra, Australian Capital Territory, Australia
| | - Elodie Ghedin
- Center for Vaccine Research, Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Jay V. DePasse
- Center for Vaccine Research, Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Adam Fitch
- Center for Vaccine Research, Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Isabella M. Cattadori
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Peter J. Hudson
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - David C. Tscharke
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Andrew F. Read
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Edward C. Holmes
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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31
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Kerr PJ. Myxomatosis in Australia and Europe: a model for emerging infectious diseases. Antiviral Res 2012; 93:387-415. [PMID: 22333483 DOI: 10.1016/j.antiviral.2012.01.009] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 01/20/2012] [Accepted: 01/26/2012] [Indexed: 11/18/2022]
Abstract
Myxoma virus is a poxvirus naturally found in two American leporid (rabbit) species (Sylvilagus brasiliensis and Sylvilagus bachmani) in which it causes an innocuous localised cutaneous fibroma. However, in European rabbits (Oryctolagus cuniculus) the same virus causes the lethal disseminated disease myxomatosis. The introduction of myxoma virus into the European rabbit population in Australia in 1950 initiated the best known example of what happens when a novel pathogen jumps into a completely naïve new mammalian host species. The short generation time of the rabbit and their vast numbers in Australia meant evolution could be studied in real time. The carefully documented emergence of attenuated strains of virus that were more effectively transmitted by the mosquito vector and the subsequent selection of rabbits with genetic resistance to myxomatosis is the paradigm for pathogen virulence and host-pathogen coevolution. This natural experiment was repeated with the release of a separate strain of myxoma virus in France in 1952. The subsequent spread of the virus throughout Europe and its coevolution with the rabbit essentially paralleled what occurred in Australia. Detailed molecular studies on myxoma virus have dissected the role of virulence genes in the pathogenesis of myxomatosis and when combined with genomic data and reverse genetics should in future enable the understanding of the molecular evolution of the virus as it adapted to its new host. This review describes the natural history and evolution of myxoma virus together with the molecular biology and experimental pathogenesis studies that are informing our understanding of evolution of emerging diseases.
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Affiliation(s)
- Peter J Kerr
- CSIRO Ecosystem Sciences, GPO Box 1700, Canberra, ACT 2601, Australia.
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Abstract
Viruses are the most abundant and diverse pathogens challenging the host immune system, and as such are a severe threat to human health. To this end, viruses have evolved multiple strategies to evade and subvert the host immune response. Host-pathogen interactions are usually initiated via recognition of pathogen-associated molecular patterns (PAMPs) by host sensors known as pattern recognition receptors (PRRs), which include, Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), NOD-like receptors (NLRs) and DNA receptors. Effective sensing of PAMPs rapidly triggers host immune responses, via activation of complex signalling pathways that culminates in the induction of inflammatory responses and the eradication of pathogens. Activation of the nuclear factor-κB (NF-κB) transcription pathway is crucial for the immediate early step of immune activation. This review discusses the recent evidence describing a variety of viral effectors that have been shown to prevent NF-κB signalling. Most of these viral effectors can be broadly classified into three categories based on the site of inhibition within the NF-κB pathway, that is, at the (i) TLRs, (ii) IKK complex or (iii) the transcriptional level.
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Affiliation(s)
- Gaëlle Le Negrate
- Institute of Medical Microbiology and Hospital Hygiene, Heinrich Heine University, Düsseldorf, Germany.
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Guo CJ, Chen WJ, Yuan LQ, Yang LS, Weng SP, Yu XQ, He JG. The viral ankyrin repeat protein (ORF124L) from infectious spleen and kidney necrosis virus attenuates nuclear factor-κB activation and interacts with IκB kinase β. J Gen Virol 2011; 92:1561-1570. [PMID: 21471317 DOI: 10.1099/vir.0.031120-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The ankyrin (ANK) repeat is one of the most common protein–protein interaction motifs, found predominantly in eukaryotes and bacteria, but the functions of the ANK repeat are rarely researched in animal viruses, with the exception of poxviruses. Infectious spleen and kidney necrosis virus (ISKNV) is a typical member of the genus Megalocytivirus in the family Iridoviridae and is a causative agent of epizootics in fish. The genome of ISKNV contains four putative viral ANK (vANK) repeat proteins and their functions remain largely unknown. In the present study, it was found that ORF124L, a vANK repeat protein in ISKNV, encodes a protein of 274 aa with three ANK repeats. Transcription of ORF124L was detected at 12 h post-infection (p.i.) and reached a peak at 40 h p.i. ORF124L was found to localize to both the nucleus and the cytoplasm in mandarin fish fry cells. ISKNV ORF124L interacted with the mandarin fish IκB kinase β protein (scIKKβ), and attenuated tumour necrosis factor alpha (TNF-α)- or phorbol myristate acetate (PMA)-induced activity of a nuclear factor κB (NF-κB)–luciferase reporter but did not interfere with the activity of an activator protein 1 (AP-1)–luciferase reporter. Phosphorylation of IκBα and nuclear translocation of NF-κB were also impaired by ISKNV ORF124L. In summary, ORF124L was identified as a vANK repeat protein and its role in inhibition of TNF-α-induced NF-κB signalling was investigated through interaction with the mandarin fish IKKβ. This work may help to improve our understanding of the function of fish iridovirus ANK repeat proteins.
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Affiliation(s)
- Chang-Jun Guo
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - Wei-Jian Chen
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - Li-Qun Yuan
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - Li-Shi Yang
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - Shao-Ping Weng
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - Xiao-Qiang Yu
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA
| | - Jian-Guo He
- State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
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Spiesschaert B, McFadden G, Hermans K, Nauwynck H, Van de Walle GR. The current status and future directions of myxoma virus, a master in immune evasion. Vet Res 2011; 42:76. [PMID: 21658227 PMCID: PMC3131250 DOI: 10.1186/1297-9716-42-76] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 06/09/2011] [Indexed: 01/12/2023] Open
Abstract
Myxoma virus (MYXV) gained importance throughout the twentieth century because of the use of the highly virulent Standard Laboratory Strain (SLS) by the Australian government in the attempt to control the feral Australian population of Oryctolagus cuniculus (European rabbit) and the subsequent illegal release of MYXV in Europe. In the European rabbit, MYXV causes a disease with an exceedingly high mortality rate, named myxomatosis, which is passively transmitted by biting arthropod vectors. MYXV still has a great impact on European rabbit populations around the world. In contrast, only a single cutaneous lesion, restricted to the point of inoculation, is seen in its natural long-term host, the South-American Sylvilagus brasiliensis and the North-American S. Bachmani. Apart from being detrimental for European rabbits, however, MYXV has also become of interest in human medicine in the last two decades for two reasons. Firstly, due to the strong immune suppressing effects of certain MYXV proteins, several secreted virus-encoded immunomodulators (e.g. Serp-1) are being developed to treat systemic inflammatory syndromes such as cardiovascular disease in humans. Secondly, due to the inherent ability of MYXV to infect a broad spectrum of human cancer cells, the live virus is also being developed as an oncolytic virotherapeutic to treat human cancer. In this review, an update will be given on the current status of MYXV in rabbits as well as its potential in human medicine in the twenty-first century. Table of contents Abstract 1. The virus 2. History 3. Pathogenesis and disease symptoms 4. Immunomodulatory proteins of MYXV 4.1. MYXV proteins with anti-apoptotic functions 4.1.1. Inhibition of pro-apoptotic molecules 4.1.2. Inhibition by protein-protein interactions by ankyrin repeat viral proteins 4.1.3. Inhibition of apoptosis by enhancing the degradation of cellular proteins 4.1.4. Inhibition of apoptosis by blocking host Protein Kinase R (PKR) 4.2. MYXV proteins interfering with leukocyte chemotaxis 4.3. MYXV serpins that inhibit cellular pro-inflammatory or pro-apoptotic proteases 4.4. MYXV proteins that interfere with leukocyte activation 4.5. MYXV proteins with sequence similarity to HIV proteins 4.6. MYXV proteins with unknown immune function 5. Vaccination strategies against myxomatosis 5.1. Current MYXV vaccines 5.2. Vaccination campaigns to protect European rabbits in the wild 6. Applications of myxoma virus for human medicine 6.1. MYXV proteins as therapeutics for allograft vasculopathy and atherosclerosis 6.2. Applications for MYXV as a live oncolytic virus to treat cancer 7. Discussion and Conclusions 8. List of Abbreviations References Author Details Authors' contributions Competing interests Figure Legends Acknowledgements
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Affiliation(s)
- Bart Spiesschaert
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
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Diel DG, Luo S, Delhon G, Peng Y, Flores EF, Rock DL. Orf virus ORFV121 encodes a novel inhibitor of NF-kappaB that contributes to virus virulence. J Virol 2011; 85:2037-49. [PMID: 21177808 PMCID: PMC3067802 DOI: 10.1128/jvi.02236-10] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 12/07/2010] [Indexed: 11/20/2022] Open
Abstract
Orf virus (ORFV), the type member of the genus Parapoxvirus of the Poxviridae, has evolved novel strategies (proteins and/or mechanisms of action) to modulate host cell responses regulated by the nuclear factor-κB (NF-κB) signaling pathway. Here, we present data indicating that ORFV ORFV121, a gene unique to parapoxviruses, encodes a novel viral NF-κB inhibitor that binds to and inhibits the phosphorylation and nuclear translocation of NF-κB-p65. The infection of cells with an ORFV121 deletion mutant virus (OV-IA82Δ121) resulted in increased NF-κB-mediated gene transcription, and the expression of ORFV121 in cell cultures significantly suppressed NF-κB-regulated reporter gene expression. ORFV ORFV121 physically interacts with NF-κB-p65 in the cell cytoplasm, thus providing a mechanism for the inhibition of NF-κB-p65 phosphorylation and nuclear translocation. Notably, the deletion of ORFV121 from the viral genome markedly decreased ORFV virulence and disease pathogenesis in sheep, indicating that ORFV121 is a virulence determinant for ORFV in the natural host.
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Affiliation(s)
- D. G. Diel
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - S. Luo
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - G. Delhon
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - Y. Peng
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - E. F. Flores
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - D. L. Rock
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Rio Grande do Sul, Brazil, Department of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
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Diel DG, Luo S, Delhon G, Peng Y, Flores EF, Rock DL. A nuclear inhibitor of NF-kappaB encoded by a poxvirus. J Virol 2011; 85:264-75. [PMID: 20980501 PMCID: PMC3014193 DOI: 10.1128/jvi.01149-10] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Accepted: 10/21/2010] [Indexed: 12/19/2022] Open
Abstract
Poxviruses have evolved various strategies to inhibit cytoplasmic events leading to activation of the nuclear factor κB (NF-κB) signaling pathway, with individual viruses often encoding multiple NF-κB inhibitors. Here, the novel orf virus (ORFV)-encoded protein ORFV002 was shown to inhibit nuclear events regulating NF-κB transcriptional activity. ORFV002 expression in cell cultures significantly decreased wild-type-virus-, tumor necrosis factor alpha (TNF-α)-, and lipopolysaccharide (LPS)-induced NF-κB-mediated gene expression. Expression of ORFV002 in cells, while not affecting phosphorylation or nuclear translocation of NF-κB-p65, markedly decreased TNF-α- and wild-type-virus-induced acetylation of NF-κB-p65, a p300-mediated nuclear modification of NF-κB-p65 that regulates its transactivating activity. ORFV002 was shown to colocalize and interact with NF-κB-p65, and expression of ORFV002 in cell cultures resulted in a reduced interaction of NF-κB-p65 with p300, suggesting that ORFV002 interferes with NF-κB-p65/p300 association. Deletion of ORFV002 from the OV-IA82 genome had no significant effect on ORFV pathogenesis in sheep, indicating that ORFV002 is nonessential for virus virulence in the natural host. This represents the first description of a nuclear inhibitor of NF-κB encoded by a poxvirus.
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Affiliation(s)
- D. G. Diel
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - S. Luo
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - G. Delhon
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - Y. Peng
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - E. F. Flores
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
| | - D. L. Rock
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, Programa de Pós-graduação em Medicina Veterinária, Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, RS, Brazil, School of Veterinary and Biomedical Sciences and Nebraska Center for Virology, University of Nebraska—Lincoln, Lincoln, Nebraska, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangdong, China
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Barry M, van Buuren N, Burles K, Mottet K, Wang Q, Teale A. Poxvirus exploitation of the ubiquitin-proteasome system. Viruses 2010; 2:2356-2380. [PMID: 21994622 PMCID: PMC3185573 DOI: 10.3390/v2102356] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 09/27/2010] [Accepted: 09/30/2010] [Indexed: 12/19/2022] Open
Abstract
Ubiquitination plays a critical role in many cellular processes. A growing number of viruses have evolved strategies to exploit the ubiquitin-proteasome system, including members of the Poxviridae family. Members of the poxvirus family have recently been shown to encode BTB/kelch and ankyrin/F-box proteins that interact with cullin-3 and cullin-1 based ubiquitin ligases, respectively. Multiple members of the poxvirus family also encode ubiquitin ligases with intrinsic activity. This review describes the numerous mechanisms that poxviruses employ to manipulate the ubiquitin-proteasome system.
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Affiliation(s)
- Michele Barry
- Author to whom correspondence should be addressed: E-Mail: ; Tel.: +1 780 492-0702; Fax: +1 780 492-7521
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Cavadini P, Botti G, Barbieri I, Lavazza A, Capucci L. Molecular characterization of SG33 and Borghi vaccines used against myxomatosis. Vaccine 2010; 28:5414-20. [DOI: 10.1016/j.vaccine.2010.06.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 05/06/2010] [Accepted: 06/04/2010] [Indexed: 11/25/2022]
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Gupta SC, Sundaram C, Reuter S, Aggarwal BB. Inhibiting NF-κB activation by small molecules as a therapeutic strategy. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:775-87. [PMID: 20493977 DOI: 10.1016/j.bbagrm.2010.05.004] [Citation(s) in RCA: 569] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Accepted: 05/08/2010] [Indexed: 12/21/2022]
Abstract
Because nuclear factor-κB (NF-κB) is a ubiquitously expressed proinflammatory transcription factor that regulates the expression of over 500 genes involved in cellular transformation, survival, proliferation, invasion, angiogenesis, metastasis, and inflammation, the NF-κB signaling pathway has become a potential target for pharmacological intervention. A wide variety of agents can activate NF-κB through canonical and noncanonical pathways. Canonical pathway involves various steps including the phosphorylation, ubiquitination, and degradation of the inhibitor of NF-κB (IκBα), which leads to the nuclear translocation of the p50-p65 subunits of NF-κB followed by p65 phosphorylation, acetylation and methylation, DNA binding, and gene transcription. Thus, agents that can inhibit protein kinases, protein phosphatases, proteasomes, ubiquitination, acetylation, methylation, and DNA binding steps have been identified as NF-κB inhibitors. Because of the critical role of NF-κB in cancer and various chronic diseases, numerous inhibitors of NF-κB have been identified. In this review, however, we describe only small molecules that suppress NF-κB activation, and the mechanism by which they block this pathway.
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Affiliation(s)
- Subash C Gupta
- Cytokine Research Laboratory, Department of Experimental Therapeutics, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
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Blanié S, Gelfi J, Bertagnoli S, Camus-Bouclainville C. MNF, an ankyrin repeat protein of myxoma virus, is part of a native cellular SCF complex during viral infection. Virol J 2010; 7:56. [PMID: 20211013 PMCID: PMC2842262 DOI: 10.1186/1743-422x-7-56] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Accepted: 03/08/2010] [Indexed: 01/02/2023] Open
Abstract
Myxoma virus (MYXV), a member of the Poxviridae family, is the agent responsible for myxomatosis, a fatal disease in the European rabbit (Oryctolagus cuniculus). Like all poxviruses, MYXV is known for encoding multiple proteins that regulate cellular signaling pathways. Among them, four proteins share the same ANK/PRANC structure: M148R, M149R, MNF (Myxoma Nuclear factor) and M-T5, all of them described as virulence factors. This family of poxvirus proteins, recently identified, has drawn considerable attention for its potential role in modulating the host ubiquitin-proteasome system during viral infection. To date, many members of this novel protein family have been shown to interact with SCF components, in vitro. Here, we focus on MNF gene, which has been shown to express a nuclear protein presenting nine ANK repeats, one of which has been identified as a nuclear localization signal. In transfection, MNF has been shown to colocalise with the transcription factor NF-κB in the nucleus of TNFα-stimulated cells. Functionally, MNF is a critical virulence factor since its deletion generates an almost apathogenic virus. In this study, to pursue the investigation of proteins interacting with MNF and of its mechanism of action, we engineered a recombinant MYXV expressing a GFP-linked MNF under the control of MNF native promoter. Infection of rabbits with MYXV-GFPMNF recombinant virus provided the evidence that the GFP fusion does not disturb the main function of MNF. Hence, cells were infected with MYXV-GFPMNF and immunoprecipitation of the GFPMNF fusion protein was performed to identify MNF's partners. For the first time, endogenous components of SCF (Cullin-1 and Skp1) were co-precipitated with an ANK myxoma virus protein, expressed in an infectious context, and without over-expression of any protein.
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Affiliation(s)
- Sophie Blanié
- INRA, UMR 1225 Interactions Hôtes - Agents Pathogènes F-31076 Toulouse, France
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A novel inhibitor of the NF-{kappa}B signaling pathway encoded by the parapoxvirus orf virus. J Virol 2010; 84:3962-73. [PMID: 20147406 DOI: 10.1128/jvi.02291-09] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The parapoxvirus orf virus (ORFV) is a pathogen of sheep and goats that has been used as a preventive and therapeutic immunomodulatory agent in several animal species. However, the functions (genes, proteins, and mechanisms of action) evolved by ORFV to modulate and manipulate immune responses are poorly understood. Here, the novel ORFV protein ORFV024 was shown to inhibit activation of the NF-kappaB signaling pathway, an important modulator of early immune responses against viral infections. Infection of primary ovine cells with an ORFV024 deletion mutant virus resulted in a marked increase in expression of NF-kappaB-regulated chemokines and other proinflammatory host genes. Expression of ORFV024 in cell cultures significantly decreased lipopolysaccharide (LPS)- and tumor necrosis factor alpha (TNF-alpha)-induced NF-kappaB-responsive reporter gene expression. Further, ORFV024 expression decreased TNF-alpha-induced phosphorylation and nuclear translocation of NF-kappaB-p65, phosphorylation, and degradation of IkappaBalpha, and phosphorylation of IkappaB kinase (IKK) subunits IKKalpha and IKKbeta, indicating that ORFV024 functions by inhibiting activation of IKKs, the bottleneck for most NF-kappaB activating stimuli. Although ORFV024 interferes with activation of the NF-kappaB signaling pathway, its deletion from the OV-IA82 genome had no significant effect on disease severity, progression, and time to resolution in sheep, indicating that ORFV024 is not essential for virus virulence in the natural host. This represents the first description of a NF-kappaB inhibitor encoded by a parapoxvirus.
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42
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Functional diversity of ankyrin repeats in microbial proteins. Trends Microbiol 2009; 18:132-9. [PMID: 19962898 DOI: 10.1016/j.tim.2009.11.004] [Citation(s) in RCA: 159] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 10/09/2009] [Accepted: 11/11/2009] [Indexed: 12/18/2022]
Abstract
The ankyrin repeat (ANK) is the most common protein-protein interaction motif in nature, and is predominantly found in eukaryotic proteins. Genome sequencing of various pathogenic or symbiotic bacteria and eukaryotic viruses has identified numerous genes encoding ANK-containing proteins that are proposed to have been acquired from eukaryotes by horizontal gene transfer. However, the recent discovery of additional ANK-containing proteins encoded in the genomes of archaea and free-living bacteria suggests either a more ancient origin of the ANK motif or multiple convergent evolution events. Many bacterial pathogens employ various types of secretion systems to deliver ANK-containing proteins into eukaryotic cells, where they mimic or manipulate various host functions. Studying the molecular and biochemical functions of this family of proteins will enhance our understanding of important host-microbe interactions.
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Rahman MM, Mohamed MR, Kim M, Smallwood S, McFadden G. Co-regulation of NF-kappaB and inflammasome-mediated inflammatory responses by myxoma virus pyrin domain-containing protein M013. PLoS Pathog 2009; 5:e1000635. [PMID: 19851467 PMCID: PMC2762494 DOI: 10.1371/journal.ppat.1000635] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 09/25/2009] [Indexed: 02/07/2023] Open
Abstract
NF-kappaB and inflammasomes both play central roles in orchestrating anti-pathogen responses by rapidly inducing a variety of early-response cytokines and chemokines following infection. Myxoma virus (MYXV), a pathogenic poxvirus of rabbits, encodes a member of the cellular pyrin domain (PYD) superfamily, called M013. The viral M013 protein was previously shown to bind host ASC-1 protein and inhibit the cellular inflammasome complex that regulates the activation and secretion of caspase 1-regulated cytokines such as IL-1beta and IL-18. Here, we report that human THP-1 monocytic cells infected with a MYXV construct deleted for the M013L gene (vMyxM013-KO), in stark contrast to the parental MYXV, rapidly induce high levels of secreted pro-inflammatory cytokines like TNF, IL-6, and MCP-1, all of which are regulated by NF-kappaB. The induction of these NF-kappaB regulated cytokines following infection with vMyxM013-KO was also confirmed in vivo using THP-1 derived xenografts in NOD-SCID mice. vMyxM013-KO virus infection specifically induced the rapid phosphorylation of IKK and degradation of IkappaBalpha, which was followed by nuclear translocation of NF-kappaB/p65. Even in the absence of virus infection, transiently expressed M013 protein alone inhibited cellular NF-kappaB-mediated reporter gene expression and nuclear translocation of NF-kappaB/p65. Using protein/protein interaction analysis, we show that M013 protein also binds directly with cellular NF-kappaB1, suggesting a direct physical and functional linkage between NF-kappaB1 and ASC-1. We further demonstrate that inhibition of the inflammasome with a caspase-1 inhibitor did not prevent the induction of NF-kappaB regulated cytokines following infection with vMyxM013-KO virus, but did block the activation of IL-1beta. Thus, the poxviral M013 inhibitor exerts a dual immuno-subversive role in the simultaneous co-regulation of both the cellular inflammasome complex and NF-kappaB-mediated pro-inflammatory responses.
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Affiliation(s)
- Masmudur M. Rahman
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Mohamed R. Mohamed
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Manbok Kim
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Sherin Smallwood
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Grant McFadden
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
- * E-mail:
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The myxoma virus m-t5 ankyrin repeat host range protein is a novel adaptor that coordinately links the cellular signaling pathways mediated by Akt and Skp1 in virus-infected cells. J Virol 2009; 83:12068-83. [PMID: 19776120 DOI: 10.1128/jvi.00963-09] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Most poxviruses express multiple proteins containing ankyrin (ANK) repeats accounting for a large superfamily of related but unique determinants of poxviral tropism. Recently, select members of this novel family of poxvirus proteins have drawn considerable attention for their potential roles in modulating intracellular signaling networks during viral infection. The rabbit-specific poxvirus, myxoma virus (MYXV), encodes four unique ANK repeat proteins, termed M-T5, M148, M149, and M150, all of which include a carboxy-terminal PRANC domain which closely resembles a cellular protein motif called the F-box domain. Here, we show that each MYXV-encoded ANK repeat protein, including M-T5, interacts directly with the Skp1 component of the host SCF ubiquitin ligase complex, and that the binding of M-T5 to cullin 1 is indirect via binding to Skp1 in the host SCF complex. To understand the significance of these virus-host protein interactions, the various binding domains of M-T5 were mapped. The N-terminal ANK repeats I and II were identified as being important for interaction with Akt, whereas the C-terminal PRANC/F-box-like domain was essential for binding to Skp1. We also report that M-T5 can bind Akt and the host SCF complex (via Skp1) simultaneously in MYXV-infected cells. Finally, we report that M-T5 specifically mediates the relocalization of Akt from the nucleus to the cytoplasm during infection with the wild-type MYXV, but not the M-T5 knockout version of the virus. These results indicate that ANK/PRANC proteins play a critical role in reprogramming disparate cellular signaling cascades to establish a new cellular environment more favorable for virus replication.
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45
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Molecular characterisation and recent evolution of myxoma virus in Spain. Arch Virol 2009; 154:1659-70. [DOI: 10.1007/s00705-009-0494-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Accepted: 08/05/2009] [Indexed: 12/27/2022]
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Poxvirus host range protein CP77 contains an F-box-like domain that is necessary to suppress NF-kappaB activation by tumor necrosis factor alpha but is independent of its host range function. J Virol 2009; 83:4140-52. [PMID: 19211746 DOI: 10.1128/jvi.01835-08] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Tumor necrosis factor alpha (TNF-alpha) activates the nuclear factor kappaB (NF-kappaB) signaling pathway that regulates expression of many cellular factors playing important roles in innate immune responses and inflammation in infected hosts. Poxviruses employ many strategies to inhibit NF-kappaB activation in cells. In this report, we describe a poxvirus host range protein, CP77, which blocked NF-kappaB activation by TNF-alpha. Immunofluorescence analyses revealed that nuclear translocation of NF-kappaB subunit p65 protein in TNF-alpha-treated HeLa cells was blocked by CP77. CP77 did so without blocking IkappaBalpha phosphorylation, suggesting that upstream kinase activation was not affected by CP77. Using GST pull-down, we showed that CP77 bound to the NF-kappaB subunit p65 through the N-terminal six-ankyrin-repeat region in vitro. CP77 also bound to Cullin-1 and Skp1 of the SCF complex through a C-terminal 13-amino-acid F-box-like sequence. Both regions of CP77 are required to block NF-kappaB activation. We thus propose a model in which poxvirus CP77 suppresses NF-kappaB activation by two interactions: the C-terminal F-box of CP77 binding to the SCF complex and the N-terminal six ankyrins binding to the NF-kappaB subunit p65. In this way, CP77 attenuates innate immune response signaling in cells. Finally, we expressed CP77 or a CP77 F-box deletion protein from a vaccinia virus host range mutant (VV-hr-GFP) and showed that either protein was able to rescue the host range defect, illustrating that the F-box region, which is important for NF-kappaB modulation and binding to SCF complex, is not required for CP77's host range function. Consistently, knocking down the protein level of NF-kappaB did not relieve the growth restriction of VV-hr-GFP in HeLa cells.
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47
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Interplay between poxviruses and the cellular ubiquitin/ubiquitin-like pathways. FEBS Lett 2009; 583:607-14. [PMID: 19174161 DOI: 10.1016/j.febslet.2009.01.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 01/15/2009] [Accepted: 01/18/2009] [Indexed: 02/06/2023]
Abstract
Post-translational polypeptide tagging by conjugation with ubiquitin and ubiquitin-like (Ub/Ubl) molecules is a potent way to alter protein functions and/or sort specific protein targets to the proteasome for degradation. Many poxviruses interfere with the host Ub/Ubl system by encoding viral proteins that can usurp this pathway. Some of these include viral proteins of the membrane-associated RING-CH (MARCH) domain, p28/Really Interesting New Gene (RING) finger, ankyrin-repeat/F-box and Broad-complex, Tramtrack and Bric-a-Brac (BTB)/Kelch subgroups of the E3 Ub ligase superfamily. Here we describe and discuss the various strategies used by poxviruses to target and subvert the host cell Ub/Ubl systems.
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48
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Genome comparison of a nonpathogenic myxoma virus field strain with its ancestor, the virulent Lausanne strain. J Virol 2008; 83:2397-403. [PMID: 19091868 DOI: 10.1128/jvi.02189-08] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
One of the best-studied examples of host-virus coevolution is the release of myxoma virus (MV) for biological control of European rabbits in Australia and Europe. To investigate the genetic basis of MV adaptation to its new host, we sequenced the genome of 6918, an attenuated Spanish field strain, and compared it with that of Lausanne, the strain originally released in Europe in 1952. Although isolated 43 years apart, the genomes were highly conserved (99.95% identical). Only 32 of the 159 MV predicted proteins revealed amino acid changes. Four genes (M009L, M036L, M135R, and M148R) in 6918 were disrupted by frameshift mutations.
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49
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Blanié S, Mortier J, Delverdier M, Bertagnoli S, Camus-Bouclainville C. M148R and M149R are two virulence factors for myxoma virus pathogenesis in the European rabbit. Vet Res 2008; 40:11. [PMID: 19019281 PMCID: PMC2695013 DOI: 10.1051/vetres:2008049] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Accepted: 11/13/2008] [Indexed: 11/24/2022] Open
Abstract
Myxoma virus (MYXV), a member of the Poxviridae family, is the agent responsible for myxomatosis, a fatal disease in the European rabbit (Oryctolagus cuniculus). MYXV has a linear double-stranded DNA genome that encodes several factors important for evasion from the host immune system. Among them, four ankyrin (ANK) repeat proteins were identified: M148R, M149R, M150R and M-T5. To date, only M150R and M-T5 were studied and characterized as critical virulence factors. This article presents the first characterization of M148R and M149R. Green Fluorescent Protein (GFP) fusions allowed us to localize them in a viral context. Whereas M149R is only cytoplasmic, interestingly, M148R is in part located in the nucleolus, a unique feature for an ANK repeat poxviral protein. In order to evaluate their implication in viral pathogenicity, targeted M148R, M149R, or both deletions were constructed in the wild type T1 strain of myxoma virus. In vitro infection of rabbit and primate cultured cells as well as primary rabbit cells allowed us to conclude that M148R and M149R are not likely to be implicated in cell tropism or host range functions. However, in vivo experiments revealed that they are virulence factors since after infection of European rabbits with mutant viruses, a delay in the onset of clinical signs, an increase of survival time and a dramatic decrease in mortality rate were observed. Moreover, histological analysis suggests that M148R plays a role in the subversion of host inflammatory response by MYXV.
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Poxvirus ankyrin repeat proteins are a unique class of F-box proteins that associate with cellular SCF1 ubiquitin ligase complexes. Proc Natl Acad Sci U S A 2008; 105:10955-60. [PMID: 18667692 DOI: 10.1073/pnas.0802042105] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
F-box proteins direct the degradation of an extensive range of proteins via the ubiquitin-proteasome system. Members of this large family of proteins are typically bipartite. They recruit specific substrates through a substrate-binding domain and, via the F-box, link these to core components of a major class of ubiquitin ligases (SCF1). F-box proteins thus determine the specificity of SCF1-mediated ubiquitination. F-box-like motifs were recently detected in poxvirus ankyrin repeat (ANK) proteins but clear compositional differences to typical F-box proteins raise questions regarding the classification and function of the motif. Here we show that all five ANK proteins of a representative poxvirus, Orf virus, interact in vivo with core components of the SCF1 ubiquitin ligase complex. Interaction is dependent on the poxviral F-box-like motif and the adaptor subunit of the complex (SKP1). The viral protein does not block enzymatic activity of the complex. These observations identify the poxviral motif as a functional F-box. They also identify a new class of F-box that in contrast to cellular counterparts is truncated, has an extreme C-terminal location and is paired with an ANK protein-binding domain. ANK proteins constitute the largest family of poxviral proteins but their function and the significance of their abundance have remained an enigma. We propose that poxviruses use these unique ANK/F-box proteins to dictate target specificity to SCF1 ubiquitin ligases and thereby exploit the cell's ubiquitin-proteasome machinery.
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