1
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Yang JX, Chen X, Li YY, Song TY, Ge JQ. Isolation of a novel adomavirus from cultured American eels, Anguilla rostrata, with haemorrhagic gill necrosis disease. J Fish Dis 2021; 44:1811-1818. [PMID: 34324718 DOI: 10.1111/jfd.13500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/10/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Recently, the culture of American eels (Anguilla rostrate) in China has been impacted by emergence of a disease with signs of haemorrhagic gill necrosis. The gills of diseased eels are covered with petecchia and they bleed when the operculum is pressed. In this study, a novel American eel adomavirus (AEAdoV) was isolated from the diseased eels using the eel ovary cell line (EO). The virus proliferated in the EO cells with a maximum TCID50 /ml of 106.29 ± 0.23 at 6 days post-infection. The virions were non-enveloped with a diameter of 75-85 nm and shown to be a DNA virus upon 5-iodo-2'-deoxyuridine (IDU) treatment. PCR assays showed that AEAdoV encodes a superfamily 3 helicases (S3H) replicase and shared high similarities with Anguilla marmorata adomavirus (MEAdoV). Although no clinical signs or mortality was observed among the eels injected with AEAdoV, the virus was reisolated from livers, kidneys and gills of injected eels at 35 days post-injection. Our results suggested that AEAdoV exhibited a latent infection in A. rostrata. The pathogenicity of the AEAdoV needs to be confirmed further.
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Affiliation(s)
- Jin-Xian Yang
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Xi Chen
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Ying-Ying Li
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Tie-Ying Song
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Jun-Qing Ge
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, China
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2
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O’Hara BA, Gee GV, Haley SA, Morris-Love J, Nyblade C, Nieves C, Hanson BA, Dang X, Turner TJ, Chavin JM, Lublin A, Koralnik IJ, Atwood WJ. Teriflunomide Inhibits JCPyV Infection and Spread in Glial Cells and Choroid Plexus Epithelial Cells. Int J Mol Sci 2021; 22:ijms22189809. [PMID: 34575975 PMCID: PMC8468119 DOI: 10.3390/ijms22189809] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/18/2021] [Accepted: 08/24/2021] [Indexed: 11/16/2022] Open
Abstract
Several classes of immunomodulators are used for treating relapsing-remitting multiple sclerosis (RRMS). Most of these disease-modifying therapies, except teriflunomide, carry the risk of progressive multifocal leukoencephalopathy (PML), a severely debilitating, often fatal virus-induced demyelinating disease. Because teriflunomide has been shown to have antiviral activity against DNA viruses, we investigated whether treatment of cells with teriflunomide inhibits infection and spread of JC polyomavirus (JCPyV), the causative agent of PML. Treatment of choroid plexus epithelial cells and astrocytes with teriflunomide reduced JCPyV infection and spread. We also used droplet digital PCR to quantify JCPyV DNA associated with extracellular vesicles isolated from RRMS patients. We detected JCPyV DNA in all patients with confirmed PML diagnosis (n = 2), and in six natalizumab-treated (n = 12), two teriflunomide-treated (n = 7), and two nonimmunomodulated (n = 2) patients. Of the 21 patients, 12 (57%) had detectable JCPyV in either plasma or serum. CSF was uniformly negative for JCPyV. Isolation of extracellular vesicles did not increase the level of detection of JCPyV DNA versus bulk unprocessed biofluid. Overall, our study demonstrated an effect of teriflunomide inhibiting JCPyV infection and spread in glial and choroid plexus epithelial cells. Larger studies using patient samples are needed to correlate these in vitro findings with patient data.
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Affiliation(s)
- Bethany A. O’Hara
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
| | - Gretchen V. Gee
- MassBiologics, University of Massachusetts Medical School, Worcester, MA 01601, USA;
| | - Sheila A. Haley
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
| | - Jenna Morris-Love
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
| | - Charlotte Nyblade
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
| | - Chris Nieves
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
| | - Barbara A. Hanson
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60007, USA; (B.A.H.); (X.D.); (I.J.K.)
| | - Xin Dang
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60007, USA; (B.A.H.); (X.D.); (I.J.K.)
| | | | | | - Alex Lublin
- Sanofi, Cambridge, MA 02114, USA; (T.J.T.); (J.M.C.); (A.L.)
| | - Igor J. Koralnik
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60007, USA; (B.A.H.); (X.D.); (I.J.K.)
| | - Walter J. Atwood
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02903, USA; (B.A.O.); (S.A.H.); (J.M.-L.); (C.N.); (C.N.)
- Correspondence: ; Tel.: +1-401-863-3116
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3
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Khalifa ME, MacDiarmid RM. A Mechanically Transmitted DNA Mycovirus Is Targeted by the Defence Machinery of Its Host, Botrytis cinerea. Viruses 2021; 13:v13071315. [PMID: 34372522 PMCID: PMC8309985 DOI: 10.3390/v13071315] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/03/2021] [Accepted: 07/05/2021] [Indexed: 12/11/2022] Open
Abstract
Eukaryotic circular single-stranded DNA (ssDNA) viruses were known only to infect plants and vertebrates until the discovery of the isolated DNA mycovirus from the fungus Sclerotinia sclerotiorum. Similar viral sequences were reported from several other sources and classified in ten genera within the Genomoviridae family. The current study reports two circular ssDNA mycoviruses isolated from the phytopathogen Botrytis cinerea, and their assignment to a newly created genus tentatively named Gemydayirivirus. The mycoviruses, tentatively named botrytis gemydayirivirus 1 (BGDaV1) and BGDaV2, are 1701 and 1693 nt long and encode three and two open reading frames (ORFs), respectively. Of the predicted ORFs, only ORF I, which codes for a replication initiation protein (Rep), shared identity with other proteins in GenBank. BGDaV1 is infective as cell-free purified particles and confers hypovirulence on its natural host. Investigation revealed that BGDaV1 is a target for RNA silencing and genomic DNA methylation, keeping the virus at very low titre. The discovery of BGDaV1 expands our knowledge of the diversity of genomoviruses and their interaction with fungal hosts.
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Affiliation(s)
- Mahmoud E. Khalifa
- The New Zealand Institute for Plant and Food Research Limited, Auckland 1025, New Zealand;
- Botany and Microbiology Department, Faculty of Science, Damietta University, Damietta 34517, Egypt
- Correspondence:
| | - Robin M. MacDiarmid
- The New Zealand Institute for Plant and Food Research Limited, Auckland 1025, New Zealand;
- School of Biological Sciences, The University of Auckland, Auckland 1010, New Zealand
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4
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Shen Q, Wang YE, Palazzo AF. Crosstalk between nucleocytoplasmic trafficking and the innate immune response to viral infection. J Biol Chem 2021; 297:100856. [PMID: 34097873 PMCID: PMC8254040 DOI: 10.1016/j.jbc.2021.100856] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 12/16/2022] Open
Abstract
The nuclear pore complex is the sole gateway connecting the nucleoplasm and cytoplasm. In humans, the nuclear pore complex is one of the largest multiprotein assemblies in the cell, with a molecular mass of ∼110 MDa and consisting of 8 to 64 copies of about 34 different nuclear pore proteins, termed nucleoporins, for a total of 1000 subunits per pore. Trafficking events across the nuclear pore are mediated by nuclear transport receptors and are highly regulated. The nuclear pore complex is also used by several RNA viruses and almost all DNA viruses to access the host cell nucleoplasm for replication. Viruses hijack the nuclear pore complex, and nuclear transport receptors, to access the nucleoplasm where they replicate. In addition, the nuclear pore complex is used by the cell innate immune system, a network of signal transduction pathways that coordinates the first response to foreign invaders, including viruses and other pathogens. Several branches of this response depend on dynamic signaling events that involve the nuclear translocation of downstream signal transducers. Mounting evidence has shown that these signaling cascades, especially those steps that involve nucleocytoplasmic trafficking events, are targeted by viruses so that they can evade the innate immune system. This review summarizes how nuclear pore proteins and nuclear transport receptors contribute to the innate immune response and highlights how viruses manipulate this cellular machinery to favor infection. A comprehensive understanding of nuclear pore proteins in antiviral innate immunity will likely contribute to the development of new antiviral therapeutic strategies.
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Affiliation(s)
- Qingtang Shen
- School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China.
| | - Yifan E Wang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Alexander F Palazzo
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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5
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Abstract
Hosts and viruses are constantly evolving in response to each other: as a host attempts to suppress a virus, the virus attempts to evade and suppress the host's immune system. Here, we describe the recurrent evolution of a virulent strain of a DNA virus, which infects multiple Drosophila species. Specifically, we identified two distinct viral types that differ 100-fold in viral titer in infected individuals, with similar differences observed in multiple species. Our analysis suggests that one of the viral types recurrently evolved at least four times in the past ~30,000 years, three times in Arizona and once in another geographically distinct species. This recurrent evolution may be facilitated by an effective mutation rate which increases as each prior mutation increases viral titer and effective population size. The higher titer viral type suppresses the host-immune system and an increased virulence compared to the low viral titer type.
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Affiliation(s)
- Tom Hill
- The Department of Molecular Biosciences, University of KansasLawrenceUnited States
| | - Robert L Unckless
- The Department of Molecular Biosciences, University of KansasLawrenceUnited States
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6
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Allain TW, Stentiford GD, Bass D, Behringer DC, Bojko J. A novel nudivirus infecting the invasive demon shrimp Dikerogammarus haemobaphes (Amphipoda). Sci Rep 2020; 10:14816. [PMID: 32908207 PMCID: PMC7481228 DOI: 10.1038/s41598-020-71776-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 08/04/2020] [Indexed: 02/06/2023] Open
Abstract
The Nudiviridae are a family of large double-stranded DNA viruses that infects the cells of the gut in invertebrates, including insects and crustaceans. The phylogenetic range of the family has recently been enhanced via the description of viruses infecting penaeid shrimp, crangonid shrimp, homarid lobsters and portunid crabs. Here we extend this by presenting the genome of another nudivirus infecting the amphipod Dikerogammarus haemobaphes. The virus, which infects cells of the host hepatopancreas, has a circular genome of 119,754 bp in length, and encodes a predicted 106 open reading frames. This novel virus encodes all the conserved nudiviral genes (sharing 57 gene homologues with other crustacean-infecting nudiviruses) but appears to lack the p6.9 gene. Phylogenetic analysis revealed that this virus branches before the other crustacean-infecting nudiviruses and shares low levels of gene/protein similarity to the Gammanudivirus genus. Comparison of gene synteny from known crustacean-infecting nudiviruses reveals conservation between Homarus gammarus nudivirus and Penaeus monodon nudivirus; however, three genomic rearrangements in this novel amphipod virus appear to break the gene synteny between this and the ones infecting lobsters and penaeid shrimp. We explore the evolutionary history and systematics of this novel virus, suggesting that it be included in the novel Epsilonnudivirus genus (Nudiviridae).
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Affiliation(s)
- Thomas W Allain
- School of Forest Resource and Conservation, University of Florida, Gainesville, FL, 32611, USA
| | - Grant D Stentiford
- International Centre of Excellence for Aquatic Animal Health, Centre for Environment, Fisheries and Aquatic Science (Cefas), Weymouth, Dorset, DT4 8UB, UK
- Centre for Sustainable Aquaculture Futures, Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4PY, UK
| | - David Bass
- International Centre of Excellence for Aquatic Animal Health, Centre for Environment, Fisheries and Aquatic Science (Cefas), Weymouth, Dorset, DT4 8UB, UK
- Centre for Sustainable Aquaculture Futures, Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4PY, UK
| | - Donald C Behringer
- School of Forest Resource and Conservation, University of Florida, Gainesville, FL, 32611, USA
- Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, 32653, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32611, USA
| | - Jamie Bojko
- School of Health and Life Science, Teesside University, Middlesbrough, TS1 3BA, UK.
- National Horizons Centre of Excellence in Bioscience Industry, Teesside University, Darlington, DL1 1HG, UK.
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7
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Mendes AF, Goncalves P, Serrano-Solis V, Silva PMD. Identification of candidate microRNAs from Ostreid herpesvirus-1 (OsHV-1) and their potential role in the infection of Pacific oysters (Crassostrea gigas). Mol Immunol 2020; 126:153-164. [PMID: 32853878 DOI: 10.1016/j.molimm.2020.08.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/31/2020] [Accepted: 08/06/2020] [Indexed: 12/21/2022]
Abstract
Oyster production is an economic activity of great interest worldwide. Recently, oysters have been suffering significant mortalities from OsHV-1infection, which has resulted in substantial economic loses in several countries around the world. Understanding viral pathogenicity mechanisms is of central importance for the establishment of disease control measures. Thus, the present work aimed to identify and characterize miRNAs from OsHV-1 as well as to predict their target transcripts in the virus and the host. OsHV-1 genome was used for the in silico discovery of pre-miRNAs. Subsequently, viral and host target transcripts of the OsHV-1 miRNAs were predicted according to the base pairing interaction between mature miRNAs and mRNA 3' untranslated regions (UTRs). Six unique pre-miRNAs were found in different regions of the viral genome, ranging in length from 85 to 172 nucleotides. A complex network of self-regulation of viral gene expression mediated by the miRNAs was identified. These sequences also seem to have a broad ability to regulate the expression of host immune-related genes, especially those associated with pathogen recognition. Our results suggest that OsHV-1 encodes miRNAs with important functions in the infection process, inducing self-regulation of viral transcripts, as well as affecting the regulation of Pacific oyster transcripts related to immunity. Understanding the molecular basis of host-pathogen interactions can help mitigate the recurrent events of oyster mass mortalities by OsHV-1 observed worldwide.
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Affiliation(s)
- Andrei Félix Mendes
- Laboratório de Imunologia e Patologia de Invertebrados (LABIPI), Departamento de Biologia Molecular, Universidade Federal da Paraíba (UFPB), 58051-900, João Pessoa, Paraíba, Brazil
| | - Priscila Goncalves
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
| | - Victor Serrano-Solis
- Laboratório de Imunologia e Patologia de Invertebrados (LABIPI), Departamento de Biologia Molecular, Universidade Federal da Paraíba (UFPB), 58051-900, João Pessoa, Paraíba, Brazil
| | - Patricia Mirella da Silva
- Laboratório de Imunologia e Patologia de Invertebrados (LABIPI), Departamento de Biologia Molecular, Universidade Federal da Paraíba (UFPB), 58051-900, João Pessoa, Paraíba, Brazil.
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8
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Baggiani M, Dell’Anno MT, Pistello M, Conti L, Onorati M. Human Neural Stem Cell Systems to Explore Pathogen-Related Neurodevelopmental and Neurodegenerative Disorders. Cells 2020; 9:E1893. [PMID: 32806773 PMCID: PMC7464299 DOI: 10.3390/cells9081893] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/07/2020] [Accepted: 08/09/2020] [Indexed: 12/18/2022] Open
Abstract
Building and functioning of the human brain requires the precise orchestration and execution of myriad molecular and cellular processes, across a multitude of cell types and over an extended period of time. Dysregulation of these processes affects structure and function of the brain and can lead to neurodevelopmental, neurological, or psychiatric disorders. Multiple environmental stimuli affect neural stem cells (NSCs) at several levels, thus impairing the normal human neurodevelopmental program. In this review article, we will delineate the main mechanisms of infection adopted by several neurotropic pathogens, and the selective NSC vulnerability. In particular, TORCH agents, i.e., Toxoplasma gondii, others (including Zika virus and Coxsackie virus), Rubella virus, Cytomegalovirus, and Herpes simplex virus, will be considered for their devastating effects on NSC self-renewal with the consequent neural progenitor depletion, the cellular substrate of microcephaly. Moreover, new evidence suggests that some of these agents may also affect the NSC progeny, producing long-term effects in the neuronal lineage. This is evident in the paradigmatic example of the neurodegeneration occurring in Alzheimer's disease.
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Affiliation(s)
- Matteo Baggiani
- Unit of Cell and Developmental Biology, Department of Biology, University of Pisa, 56126 Pisa, Italy;
| | - Maria Teresa Dell’Anno
- Cellular Engineering Laboratory, Fondazione Pisana per la Scienza ONLUS, 56017 Pisa, Italy;
| | - Mauro Pistello
- Retrovirus Center and Virology Section, Department of Translational Research, University of Pisa and Virology Division, Pisa University Hospital, 56100 Pisa, Italy;
| | - Luciano Conti
- Department of Cellular, Computational and Integrative Biology—CIBIO, University of Trento, 38122 Trento, Italy;
| | - Marco Onorati
- Unit of Cell and Developmental Biology, Department of Biology, University of Pisa, 56126 Pisa, Italy;
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9
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Gao M, Yao X, Mao W, Shen C, Zhang Z, Huang Q, Cui D, Sun H, Zou W. Etiological analysis of virus, mycoplasma pneumoniae and chlamydia pneumoniae in hospitalized children with acute respiratory infections in Huzhou. Virol J 2020; 17:119. [PMID: 32738914 PMCID: PMC7395355 DOI: 10.1186/s12985-020-01380-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 07/02/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Acute respiratory infections are a common disease in children with high mortality and morbidity. Multiple pathogens can cause acute respiratory infections. A 2-year survey of hospitalized children was conducted to understand the epidemic situation, seasonal spread of pathogens and the improvement of clinical diagnosis, treatment and prevention of disease in Huzhou, China. METHODS From September 2017 to August 2019, 3121 nasopharyngeal swabs from hospitalized children with acute respiratory infections were collected, and real-time PCR was used to detect various pathogens. Then, pathogen profiles, frequency and seasonality were analyzed. RESULTS Of the 3121 specimens, 14.45% (451/3121) were positive for at least one pathogen. Of the single-pathogen infections, RSV (45.61%, 182/399) was the most frequent pathogen, followed by PIVs (14.79%, 59/399), ADV (14.54%, 58/399), MP (10.78%, 43/399), and IAV (5.26%, 21/399). Of the 52 coinfections, RSV + PIVs viruses were predominantly identified and accounted for 40.38% (21/52) of cases. RSV was the most frequent pathogen in all four groups. The highest positive rate of the pathogens occurred in the winter (21.26%), followed by autumn (14.98%), the summer (14.11%) and the spring (12.25%). CONCLUSION Viruses are the main pathogens in hospitalized children with acute respiratory infections in Huzhou city, Zhejiang Province, China. Among the pathogens, RSV had the highest detection rate, and MP is also a common pathogen among children with acute respiratory infections. This study provided a better understanding of the distribution of pathogens in children of different ages and seasons, which is conducive to the development of more reasonable treatment strategies and prevention and control measures.
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Affiliation(s)
- Min Gao
- Department of Clinical Laboratory, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Xing Yao
- Hepatobiliary and Pancreatic Surgery, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Wei Mao
- Department of Respiratory Diseases, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Cuifen Shen
- Department of Clinical Laboratory, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Zongxin Zhang
- Department of Clinical Laboratory, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Qiuling Huang
- Department of Pediatrics, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China
| | - Dawei Cui
- Department of Blood Transfusion, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Haiyan Sun
- Department of Clinical Laboratory, Shaoxing Second Hospital, Shaoxing, 312000, Zhejianeg Province, China
| | - Weihua Zou
- Department of Clinical Laboratory, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, 313000, China.
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10
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Ross EP, Behringer DC, Bojko J. White spot syndrome virus and the Caribbean spiny lobster, Panulirus argus: Susceptibility and behavioral immunity. J Invertebr Pathol 2019; 162:1-9. [PMID: 30731071 DOI: 10.1016/j.jip.2019.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/22/2019] [Accepted: 02/03/2019] [Indexed: 12/21/2022]
Abstract
The Caribbean spiny lobster Panulirus argus is susceptible to infection by Panulirus argus Virus 1 (PaV1), the only virus known to naturally infect any lobster species. However, P. argus is able to mitigate PaV1 transmission risk by avoiding infected individuals. P. argus may also be susceptible to another lethal virus, White Spot Syndrome Virus (WSSV). WSSV has not been documented in wild populations of spiny lobsters, but has been experimentally transmitted to six other lobster species from the genus Panulirus. Although WSSV has been detected intermittently in wild populations of shrimp in the Caribbean region, the risk to P. argus has not been evaluated. Potential emergence of the disease could result in fisheries losses and ecological disruption. To assess the risk to P. argus, we tested its susceptibility to WSSV via injection and waterborne transmission. We also tested whether healthy lobsters can detect and avoid conspecifics with qPCR-quantifiable WSSV infections. We found P. argus to be highly susceptible to WSSV via intramuscular injection, with mortality reaching 88% four weeks post inoculation. Panulirus argus was also susceptible to WSSV via waterborne transmission, but WSSV burden was low after four weeks via qPCR. Behavioral assays indicated that P. argus can detect and avoid conspecifics infected with WSSV and the avoidance response was strongest for the most heavily infected individuals - a response comparable to PaV1-infected conspecifics. Panulirus argus is the first spiny lobster found to be susceptible to WSSV in the Americas, but it is possible that a generalized avoidance response by healthy lobsters against infected conspecifics provides a behavioral defense and may reduce WSSV infection potential and prevalence. Preliminary evidence suggests that the infiltration of hemolymph constituents into the urine may be the source of the avoidance behavior and could therefore extend to other directly transmitted pathogens in spiny lobster populations preventing them from becoming common in their population.
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Affiliation(s)
- Erica P Ross
- Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA
| | - Donald C Behringer
- Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA; Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA.
| | - Jamie Bojko
- Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA; Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
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11
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King WL, Jenkins C, Go J, Siboni N, Seymour JR, Labbate M. Characterisation of the Pacific Oyster Microbiome During a Summer Mortality Event. Microb Ecol 2019; 77:502-512. [PMID: 29987529 DOI: 10.1007/s00248-018-1226-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 07/02/2018] [Indexed: 06/08/2023]
Abstract
The Pacific oyster, Crassostrea gigas, is a key commercial species that is cultivated globally. In recent years, disease outbreaks have heavily impacted C. gigas stocks worldwide, with many losses incurred during summer. A number of infectious agents have been associated with these summer mortality events, including viruses (particularly Ostreid herpesvirus 1, OsHV-1) and bacteria; however, cases where no known aetiological agent can be identified are common. In this study, we examined the microbiome of disease-affected and disease-unaffected C. gigas during a 2013-2014 summer mortality event in Port Stephens (Australia) where known oyster pathogens including OsHV-1 were not detected. The adductor muscle microbiomes of 70 C. gigas samples across 12 study sites in the Port Stephens estuary were characterised using 16S rRNA (V1-V3 region) amplicon sequencing, with the aim of comparing the influence of spatial location and disease state on the oyster microbiome. Spatial location was found to be a significant determinant of the disease-affected oyster microbiome. Furthermore, microbiome comparisons between disease states identified a significant increase in rare operational taxonomic units (OTUs) belonging to Vibrio harveyi and an unidentified member of the Vibrio genus in the disease-affected microbiome. This is indicative of a potential role of Vibrio species in oyster disease and supportive of previous culture-based examination of this mortality event.
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Affiliation(s)
- William L King
- The School of Life Sciences, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Cheryl Jenkins
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW, Australia
| | - Jeffrey Go
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW, Australia
| | - Nachshon Siboni
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Justin R Seymour
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Maurizio Labbate
- The School of Life Sciences, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia.
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12
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Wei J, Lian H, Guo W, Chen YD, Zhang XN, Zang R, Zhong L, Yang Q, Hu MM, Luo WW, Shu HB, Li S. SNX8 modulates innate immune response to DNA virus by mediating trafficking and activation of MITA. PLoS Pathog 2018; 14:e1007336. [PMID: 30321235 PMCID: PMC6188873 DOI: 10.1371/journal.ppat.1007336] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/12/2018] [Indexed: 12/29/2022] Open
Abstract
MITA (also called STING) is a central adaptor protein in innate immune response to cytosolic DNA. Cellular trafficking of MITA from the ER to perinuclear microsomes after DNA virus infection is critical for MITA activation and onset of innate antiviral response. Here we found that SNX8 is a component of DNA-triggered induction of downstream effector genes and innate immune response. Snx8-/- mice infected with the DNA virus HSV-1 exhibited lower serum cytokine levels and higher viral titers in the brains, resulting in higher lethality. Mechanistically, SNX8 recruited the class III phosphatylinositol 3-kinase VPS34 to MITA, which is required for trafficking of MITA from the ER to perinuclear microsomes. Our findings suggest that SNX8 is a critical component in innate immune response to cytosolic DNA and DNA virus. Infection by virus, such as the DNA virus herpes simplex virus 1, induces the host cells to express proteins that mediate antiviral immune response. The protein called MITA plays an essential role in the process of antiviral immune response. After viral infection, MITA traffics from the endoplasmic reticulum (ER) to perinuclear punctuate structures, a process required for its activation and induction of downstream antiviral genes. How the trafficking of MITA is regulated remains enigmatic. In this study, we found that a protein called SNX8 plays a critical role in regulation of MITA trafficking from the ER to perinuclear punctuate structures. SNX8 does this by recruiting the VPS34-containing translocon machinery to MITA. Deficiency of SNX8 impaired antiviral immune response and rendered the mice more sensitive to DNA virus-induced death. Our results suggest that SNX8 is a critical component in antiviral immune response to DNA virus.
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Affiliation(s)
- Jin Wei
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Huan Lian
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Wei Guo
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Yun-Da Chen
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Xia-Nan Zhang
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Ru Zang
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Li Zhong
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Qing Yang
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Ming-Ming Hu
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Wei-Wei Luo
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Hong-Bing Shu
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
- College of Life Sciences, Wuhan University, Wuhan, China
- * E-mail: (HBS); (SL)
| | - Shu Li
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
- * E-mail: (HBS); (SL)
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13
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Toldrà A, Andree KB, Bertomeu E, Roque A, Carrasco N, Gairín I, Furones MD, Campàs M. Rapid capture and detection of ostreid herpesvirus-1 from Pacific oyster Crassostrea gigas and seawater using magnetic beads. PLoS One 2018; 13:e0205207. [PMID: 30281676 PMCID: PMC6169968 DOI: 10.1371/journal.pone.0205207] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 09/20/2018] [Indexed: 12/20/2022] Open
Abstract
Ostreid herpesvirus-1 (OsHV-1) has been involved in mass mortality episodes of Pacific oysters Crassostrea gigas throughout the world, causing important economic losses to the aquaculture industry. In the present study, magnetic beads (MBs) coated with an anionic polymer were used to capture viable OsHV-1 from two types of naturally infected matrix: oyster homogenate and seawater. Adsorption of the virus on the MBs and characterisation of the MB-virus conjugates was demonstrated by real-time quantitative PCR (qPCR). To study the infective capacity of the captured virus, MB-virus conjugates were injected in the adductor muscle of naïve spat oysters, using oyster homogenate and seawater without MBs as positive controls, and bare MBs and sterile water as negative controls. Mortalities were induced after injection with MB-virus conjugates and in positive controls, whereas no mortalities were recorded in negative controls. Subsequent OsHV-1 DNA and RNA analysis of the oysters by qPCR and reverse transcription qPCR (RT-qPCR), respectively, confirmed that the virus was the responsible for the mortality event and the ability of the MBs to capture viable viral particles. The capture of viable OsHV-1 using MBs is a rapid and easy isolation method and a promising tool, combined with qPCR, to be applied to OsHV-1 detection in aquaculture facilities.
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Affiliation(s)
- Anna Toldrà
- IRTA, Ctra., Sant Carles de la Ràpita, Tarragona, Spain
| | | | | | - Ana Roque
- IRTA, Ctra., Sant Carles de la Ràpita, Tarragona, Spain
| | | | - Ignasi Gairín
- IRTA, Ctra., Sant Carles de la Ràpita, Tarragona, Spain
| | | | - Mònica Campàs
- IRTA, Ctra., Sant Carles de la Ràpita, Tarragona, Spain
- * E-mail:
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14
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Delisle L, Petton B, Burguin JF, Morga B, Corporeau C, Pernet F. Temperature modulate disease susceptibility of the Pacific oyster Crassostrea gigas and virulence of the Ostreid herpesvirus type 1. Fish Shellfish Immunol 2018; 80:71-79. [PMID: 29859311 DOI: 10.1016/j.fsi.2018.05.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 06/08/2023]
Abstract
Temperature triggers marine diseases by changing host susceptibility and pathogen virulence. Oyster mortalities associated with the Ostreid herpesvirus type 1 (OsHV-1) have occurred seasonally in Europe when the seawater temperature range reaches 16-24 °C. Here we assess how temperature modulates oyster susceptibility to OsHV-1 and pathogen virulence. Oysters were injected with OsHV-1 suspension incubated at 21 °C, 26 °C and 29 °C and were placed in cohabitation with healthy oysters (recipients) at these three temperatures according to a fractional factorial design. Survival was followed for 14 d and recipients were sampled for OsHV-1 DNA quantification and viral gene expression. The oysters were all subsequently placed at 21 °C to evaluate the potential for virus reactivation, before being transferred to oyster farms to evaluate their long-term susceptibility to the disease. Survival of recipients at 29 °C (86%) was higher than at 21 °C (52%) and 26 °C (43%). High temperature (29 °C) decreased the susceptibility of oysters to OsHV-1 without altering virus infectivity and virulence. At 26 °C, the virulence of OsHV-1 was enhanced. Differences in survival persisted when the recipients were all placed at 21 °C, suggesting that OsHV-1 did not reactivate. Additional oyster mortality followed the field transfer, but the overall survival of oysters infected at 29 °C remained higher.
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Affiliation(s)
- Lizenn Delisle
- Ifremer/LEMAR UMR 6539, Technopole de Brest-Iroise, 29280, Plouzané, France
| | - Bruno Petton
- Ifremer/LEMAR UMR 6539, Presqu'île du vivier, 29840, Argenton, France
| | | | - Benjamin Morga
- Ifremer/Laboratoire de génétique et Pathologie des Mollusques Marins (LGPMM), Avenue de Mus de Loup, 17390, La Tremblade, France
| | | | - Fabrice Pernet
- Ifremer/LEMAR UMR 6539, Technopole de Brest-Iroise, 29280, Plouzané, France.
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15
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Karuppannan AK, Opriessnig T. Possible risks posed by single-stranded DNA viruses of pigs associated with xenotransplantation. Xenotransplantation 2018; 25:e12453. [PMID: 30264878 PMCID: PMC6120555 DOI: 10.1111/xen.12453] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/12/2018] [Accepted: 07/20/2018] [Indexed: 12/11/2022]
Abstract
Routine large-scale xenotransplantation from pigs to humans is getting closer to clinical reality owing to several state-of-the-art technologies, especially the ability to rapidly engineer genetically defined pigs. However, using pig organs in humans poses risks including unwanted cross-species transfer of viruses and adaption of these pig viruses to the human organ recipient. Recent developments in the field of virology, including the advent of metagenomic techniques to characterize entire viromes, have led to the identification of a plethora of viruses in many niches. Single-stranded DNA (ssDNA) viruses are the largest group prevalent in virome studies in mammals. Specifically, the ssDNA viral genomes are characterized by a high rate of nucleotide substitution, which confers a proclivity to adapt to new hosts and cross-species barriers. Pig-associated ssDNA viruses include torque teno sus viruses (TTSuV) in the Anelloviridae family, porcine parvoviruses (PPV), and porcine bocaviruses (PBoV) both in the family of Parvoviridae, and porcine circoviruses (PCV) in the Circoviridae family, some of which have been confirmed to be pathogenic to pigs. The risks of these viruses for the human recipient during xenotransplantation procedures are relatively unknown. Based on the scant knowledge available on the prevalence, predilection, and pathogenicity of pig-associated ssDNA viruses, careful screening and monitoring are required. In the case of positive identification, risk assessments and strategies to eliminate these viruses in xenotransplantation pig stock may be needed.
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Affiliation(s)
- Anbu K. Karuppannan
- Department of Veterinary Diagnostic and Production Animal MedicineCollege of Veterinary MedicineIowa State UniversityAmesIowa
| | - Tanja Opriessnig
- Department of Veterinary Diagnostic and Production Animal MedicineCollege of Veterinary MedicineIowa State UniversityAmesIowa
- The Roslin Institute and The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghRoslinMidlothianUK
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16
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Abstract
When a virus infects a host cell, it hijacks the biosynthetic capacity of the cell to produce virus progeny, a process that may take less than an hour or more than a week. The overall time required for a virus to reproduce depends collectively on the rates of multiple steps in the infection process, including initial binding of the virus particle to the surface of the cell, virus internalization and release of the viral genome within the cell, decoding of the genome to make viral proteins, replication of the genome, assembly of progeny virus particles, and release of these particles into the extracellular environment. For a large number of virus types, much has been learned about the molecular mechanisms and rates of the various steps. However, in only relatively few cases during the last 50 years has an attempt been made-using mathematical modeling-to account for how the different steps contribute to the overall timing and productivity of the infection cycle in a cell. Here we review the initial case studies, which include studies of the one-step growth behavior of viruses that infect bacteria (Qβ, T7, and M13), human immunodeficiency virus, influenza A virus, poliovirus, vesicular stomatitis virus, baculovirus, hepatitis B and C viruses, and herpes simplex virus. Further, we consider how such models enable one to explore how cellular resources are utilized and how antiviral strategies might be designed to resist escape. Finally, we highlight challenges and opportunities at the frontiers of cell-level modeling of virus infections.
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Affiliation(s)
- John Yin
- Department of Chemical and Biological Engineering, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jacob Redovich
- Department of Chemical and Biological Engineering, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
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17
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Maumus F, Blanc G. Study of Gene Trafficking between Acanthamoeba and Giant Viruses Suggests an Undiscovered Family of Amoeba-Infecting Viruses. Genome Biol Evol 2016; 8:3351-3363. [PMID: 27811174 PMCID: PMC5203793 DOI: 10.1093/gbe/evw260] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2016] [Indexed: 01/10/2023] Open
Abstract
The nucleocytoplasmic large DNA viruses (NCLDV) are a group of extremely complex double-stranded DNA viruses, which are major parasites of a variety of eukaryotes. Recent studies showed that certain unicellular eukaryotes contain fragments of NCLDV DNA integrated in their genome, when surprisingly many of these organisms were not previously shown to be infected by NCLDVs. These findings prompted us to search the genome of Acanthamoeba castellanii strain Neff (Neff), one of the most prolific hosts in the discovery of giant NCLDVs, for possible DNA inserts of viral origin. We report the identification of 267 markers of lateral gene transfer with viruses, approximately half of which are clustered in Neff genome regions of viral origins, transcriptionally inactive or exhibit nucleotide-composition signatures suggestive of a foreign origin. The integrated viral genes had diverse origin among relatives of viruses that infect Neff, including Mollivirus, Pandoravirus, Marseillevirus, Pithovirus, and Mimivirus However, phylogenetic analysis suggests the existence of a yet-undiscovered family of amoeba-infecting NCLDV in addition to the five already characterized. The active transcription of some apparently anciently integrated virus-like genes suggests that some viral genes might have been domesticated during the amoeba evolution. These insights confirm that genomic insertion of NCLDV DNA is a common theme in eukaryotes. This gene flow contributed fertilizing the eukaryotic gene repertoire and participated in the occurrence of orphan genes, a long standing issue in genomics. Search for viral inserts in eukaryotic genomes followed by environmental screening of the original viruses should be used to isolate radically new NCLDVs.
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Affiliation(s)
| | - Guillaume Blanc
- Structural and Genomic Information Laboratory (IGS), Aix-Marseille Université, CNRS UMR (IMM FR 3479), Marseille, France
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18
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Le Sage V, Cinti A, Amorim R, Mouland AJ. Adapting the Stress Response: Viral Subversion of the mTOR Signaling Pathway. Viruses 2016; 8:v8060152. [PMID: 27231932 PMCID: PMC4926172 DOI: 10.3390/v8060152] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 05/16/2016] [Accepted: 05/19/2016] [Indexed: 02/06/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is a central regulator of gene expression, translation and various metabolic processes. Multiple extracellular (growth factors) and intracellular (energy status) molecular signals as well as a variety of stressors are integrated into the mTOR pathway. Viral infection is a significant stress that can activate, reduce or even suppress the mTOR signaling pathway. Consequently, viruses have evolved a plethora of different mechanisms to attack and co-opt the mTOR pathway in order to make the host cell a hospitable environment for replication. A more comprehensive knowledge of different viral interactions may provide fruitful targets for new antiviral drugs.
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Affiliation(s)
- Valerie Le Sage
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
| | - Alessandro Cinti
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
| | - Raquel Amorim
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
| | - Andrew J Mouland
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
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19
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Ziv C, Malitsky S, Othman A, Ben-Dor S, Wei Y, Zheng S, Aharoni A, Hornemann T, Vardi A. Viral serine palmitoyltransferase induces metabolic switch in sphingolipid biosynthesis and is required for infection of a marine alga. Proc Natl Acad Sci U S A 2016; 113:E1907-16. [PMID: 26984500 PMCID: PMC4822627 DOI: 10.1073/pnas.1523168113] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Marine viruses are the most abundant biological entities in the oceans shaping community structure and nutrient cycling. The interaction between the bloom-forming alga Emiliania huxleyi and its specific large dsDNA virus (EhV) is a major factor determining the fate of carbon in the ocean, thus serving as a key host-pathogen model system. The EhV genome encodes for a set of genes involved in the de novo sphingolipid biosynthesis, not reported in any viral genome to date. We combined detailed lipidomic and biochemical analyses to characterize the functional role of this virus-encoded pathway during lytic viral infection. We identified a major metabolic shift, mediated by differential substrate specificity of virus-encoded serine palmitoyltransferase, a key enzyme of sphingolipid biosynthesis. Consequently, unique viral glycosphingolipids, composed of unusual hydroxylated C17 sphingoid bases (t17:0) were highly enriched in the infected cells, and their synthesis was found to be essential for viral assembly. These findings uncover the biochemical bases of the virus-induced metabolic rewiring of the host sphingolipid biosynthesis during the chemical "arms race" in the ocean.
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Affiliation(s)
- Carmit Ziv
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sergey Malitsky
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Alaa Othman
- Institute for Clinical Chemistry, University Hospital Zurich, 8091 Zurich, Switzerland; Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, 23562 Lübeck, Germany
| | - Shifra Ben-Dor
- Biological Services Unit, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yu Wei
- Institute for Clinical Chemistry, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Shuning Zheng
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Thorsten Hornemann
- Institute for Clinical Chemistry, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel;
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21
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22
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Abstract
Infectious virus clones are one of the most powerful tools in plant pathology, molecular biology, and biotechnology. The construction of infectious clones of RNA and DNA viruses, however, usually requires laborious cloning and subcloning steps. In addition, instability of the RNA virus genome is frequently reported after its introduction into the vector and transference to Escherichia coli. These difficulties hamper the cloning procedures, making it tedious and cumbersome. This chapter describes two protocols for a simple construction of infectious viruses, an RNA virus, the tobamovirus Pepper mild mottle virus, and a DNA virus, a bipartite begomovirus. For this purpose, the strategy of overlap-extension PCR was used for the construction of infectious tobamovirus clone and of rolling circle amplification (RCA) for the construction of a dimeric form of the begomovirus clone.
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Affiliation(s)
- Tatsuya Nagata
- Laboratório de Microscopia e Virologia, Departamento de Biologia Celular, Conselho de Ensino, Pesquisa, e Extensão, Universidade de Brasília, IB-Bloco K, Asa Norte, 70910-900, Brasilia, DF, Brazil,
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23
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Schatz D, Shemi A, Rosenwasser S, Sabanay H, Wolf SG, Ben-Dor S, Vardi A. Hijacking of an autophagy-like process is critical for the life cycle of a DNA virus infecting oceanic algal blooms. New Phytol 2014; 204:854-63. [PMID: 25195618 PMCID: PMC4233938 DOI: 10.1111/nph.13008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 07/27/2014] [Indexed: 05/04/2023]
Abstract
Marine photosynthetic microorganisms are the basis of marine food webs and are responsible for nearly 50% of the global primary production. Emiliania huxleyi forms massive oceanic blooms that are routinely terminated by large double-stranded DNA coccolithoviruses. The cellular mechanisms that govern the replication cycle of these giant viruses are largely unknown. We used diverse techniques, including fluorescence microscopy, transmission electron microscopy, cryoelectron tomography, immunolabeling and biochemical methodologies to investigate the role of autophagy in host-virus interactions. Hallmarks of autophagy are induced during the lytic phase of E. huxleyi viral infection, concomitant with up-regulation of autophagy-related genes (ATG genes). Pretreatment of the infected cells with an autophagy inhibitor causes a major reduction in the production of extracellular viral particles, without reducing viral DNA replication within the cell. The host-encoded Atg8 protein was detected within purified virions, demonstrating the pivotal role of the autophagy-like process in viral assembly and egress. We show that autophagy, which is classically considered as a defense mechanism, is essential for viral propagation and for facilitating a high burst size. This cellular mechanism may have a major impact on the fate of the viral-infected blooms, and therefore on the cycling of nutrients within the marine ecosystem.
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Affiliation(s)
- Daniella Schatz
- Department of Plant Sciences, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Adva Shemi
- Department of Plant Sciences, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Shilo Rosenwasser
- Department of Plant Sciences, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Helena Sabanay
- Department of Chemical Research Support, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Sharon G Wolf
- Department of Chemical Research Support, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Shifra Ben-Dor
- Department of Biological Services, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Assaf Vardi
- Department of Plant Sciences, Weizmann Institute of ScienceRehovot, 76100, Israel
- Author for correspondence: Assaf Vardi, Tel: +972 8 934 2914,
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24
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Kendrick BJ, DiTullio GR, Cyronak TJ, Fulton JM, Van Mooy BAS, Bidle KD. Temperature-induced viral resistance in Emiliania huxleyi (Prymnesiophyceae). PLoS One 2014; 9:e112134. [PMID: 25405345 PMCID: PMC4236053 DOI: 10.1371/journal.pone.0112134] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/13/2014] [Indexed: 11/19/2022] Open
Abstract
Annual Emiliania huxleyi blooms (along with other coccolithophorid species) play important roles in the global carbon and sulfur cycles. E. huxleyi blooms are routinely terminated by large, host-specific dsDNA viruses, (Emiliania huxleyi Viruses; EhVs), making these host-virus interactions a driving force behind their potential impact on global biogeochemical cycles. Given projected increases in sea surface temperature due to climate change, it is imperative to understand the effects of temperature on E. huxleyi's susceptibility to viral infection and its production of climatically active dimethylated sulfur species (DSS). Here we demonstrate that a 3°C increase in temperature induces EhV-resistant phenotypes in three E. huxleyi strains and that successful virus infection impacts DSS pool sizes. We also examined cellular polar lipids, given their documented roles in regulating host-virus interactions in this system, and propose that alterations to membrane-bound surface receptors are responsible for the observed temperature-induced resistance. Our findings have potential implications for global biogeochemical cycles in a warming climate and for deciphering the particular mechanism(s) by which some E. huxleyi strains exhibit viral resistance.
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Affiliation(s)
- B. Jacob Kendrick
- Grice Marine Laboratory, College of Charleston, Charleston, SC, United States of America
- * E-mail:
| | - Giacomo R. DiTullio
- Grice Marine Laboratory, College of Charleston, Charleston, SC, United States of America
| | - Tyler J. Cyronak
- Grice Marine Laboratory, College of Charleston, Charleston, SC, United States of America
| | - James M. Fulton
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States of America
| | - Benjamin A. S. Van Mooy
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States of America
| | - Kay D. Bidle
- Environmental Biophysics and Molecular Ecology Group, Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States of America
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25
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Abstract
During infection, many viruses induce cellular remodeling, resulting in the formation of insoluble aggregates/inclusions, usually containing viral structural proteins. Identification of aggregates has become a useful diagnostic tool for certain viral infections. There is wide variety of viral aggregates, which differ by their location, size, content and putative function. The role of aggregation in the context of a specific virus is often poorly understood, especially in the case of plant viruses. The aggregates are utilized by viruses to house a large complex of proteins of both viral and host origin to promote virus replication, translation, intra- and intercellular transportation. Aggregated structures may protect viral functional complexes from the cellular degradation machinery. Alternatively, the activation of host defense mechanisms may involve sequestration of virus components in aggregates, followed by their neutralization as toxic for the host cell. The diversity of virus-induced aggregates in mammalian and plant cells is the subject of this review.
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Affiliation(s)
- Adi Moshe
- Institute of Plant Sciences and Genetics in Agriculture and the Otto Warburg Minerva Center for Agricultural Biotechnology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
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26
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Lietze VU, Geden CJ, Doyle MA, Boucias DG. Disease dynamics and persistence of Musca domestica salivary gland hypertrophy virus infections in laboratory house fly (Musca domestica) populations. Appl Environ Microbiol 2012; 78:311-7. [PMID: 22057863 PMCID: PMC3255755 DOI: 10.1128/aem.06500-11] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 10/25/2011] [Indexed: 11/20/2022] Open
Abstract
Past surveys of feral house fly populations have shown that Musca domestica salivary gland hypertrophy virus (MdSGHV) has a worldwide distribution, with an average prevalence varying between 0.5% and 10%. How this adult-specific virus persists in nature is unknown. In the present study, experiments were conducted to examine short-term transmission efficiency and long-term persistence of symptomatic MdSGHV infections in confined house fly populations. Average rates of disease transmission from virus-infected to healthy flies in small populations of 50 or 100 flies ranged from 3% to 24% and did not vary between three tested geographical strains that originated from different continents. Introduction of an initial proportion of 40% infected flies into fly populations did not result in epizootics. Instead, long-term observations demonstrated that MdSGHV infection levels declined over time, resulting in a 10% infection rate after passing through 10 filial generations. In all experiments, induced disease rates were significantly higher in male flies than in female flies and might be explained by male-specific behaviors that increased contact with viremic flies and/or virus-contaminated surfaces.
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Affiliation(s)
- Verena-Ulrike Lietze
- Entomology and Nematology Department, University of Florida, Gainesville, Florida, USA.
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27
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Abstract
Many species of tsetse flies (Diptera: Glossinidae) are infected with a virus that causes salivary gland hypertrophy (SGH), and flies with SGH symptoms have a reduced fecundity and fertility. The prevalence of SGH in wild tsetse populations is usually very low (0.2%–5%), but higher prevalence rates (15.2%) have been observed occasionally. The successful eradication of a Glossina austeni population from Unguja Island (Zanzibar) using an area-wide integrated pest management approach with a sterile insect technique (SIT) component (1994–1997) encouraged several African countries, including Ethiopia, to incorporate the SIT in their national tsetse control programs. A large facility to produce tsetse flies for SIT application in Ethiopia was inaugurated in 2007. To support this project, a Glossina pallidipes colony originating from Ethiopia was successfully established in 1996, but later up to 85% of adult flies displayed symptoms of SGH. As a result, the colony declined and became extinct by 2002. The difficulties experienced with the rearing of G. pallidipes, epitomized by the collapse of the G. pallidipes colony originating from Ethiopia, prompted the urgent need to develop management strategies for the salivary gland hypertrophy virus (SGHV) for this species. As a first step to identify suitable management strategies, the virus isolated from G. pallidipes (GpSGHV) was recently sequenced and research was initiated on virus transmission and pathology. Different approaches to prevent virus replication and its horizontal transmission during blood feeding have been proposed. These include the use of antiviral drugs such as acyclovir and valacyclovir added to the blood for feeding or the use of antibodies against SGHV virion proteins. In addition, preliminary attempts to silence the expression of an essential viral protein using RNA interference will be discussed.
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Affiliation(s)
- Adly M M Abd-Alla
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna, Austria.
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28
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Abstract
At present, more than 40 protist-infecting viruses have been isolated and characterized. From the viewpoints of molecular ecology, taxomony and molecular evolution, several new discoveries were made within the last five years. In this minireview, three topics of interest on protist-infecting viruses are introduced: 1) molecular ecological relationships between a bloom-forming dinoflagellate Heterocapsa circularisquama and its ssRNA virus (HcRNAV); 2) findings of new ssRNA- and ssDNA-virus groups infecting diatoms; 3) establishment of a hypothesis concerning the evolution of picornaviruses. The potential of aquatic virus studies is far-reaching and inestimable.
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Affiliation(s)
- Keizo Nagasaki
- Natl. Res. Inst. Fish. Environ. Inland Sea, Fisheries Research Agency.
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29
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Abstract
Unlike other recent viral emergences, which were in majority caused by RNA viruses, the monkeypox results from infection by a DNA virus, an orthopoxvirus closely related to both vaccine and smallpox viruses and whose two genomic variants are known. Unexpectedly isolated from captive Asiatic monkeys and first considered as an laboratory curiosity, this virus was recognised in 1970 as an human pathogen in tropical Africa. Here it was responsible for sporadic cases following intrusions (for hunting) into tropical rain forests or rare outbreak with human-to-human transmission as observed in 1996 in Democratic Republic of Congo. As monkeypox in humans is not distinguishable from smallpox (a disease globally eradicated in 1977) it was only subjected to vigilant epidemiological surveillance and not considered as a potential threat outside Africa. This point of view radically changed in 2003 when monkeypox was introduced in the USA by African wild rodents and spread to 11 different states of this country. Responsible for 82 infections in American children and adults, this outbreak led to realize the sanitary hazards resulting from international trade of exotic animals and scientific investigations increasing extensively our knowledge of this zoonosis.
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Affiliation(s)
- C Chastel
- 3, rue Rouget-de-l'Isle, 292002 Brest, France.
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30
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Huang Q, Hartung JS. Construction of infectious clones of double-stranded DNA viruses of plants using citrus yellow mosaic virus as an example. Methods Mol Biol 2008; 451:525-33. [PMID: 18370278 DOI: 10.1007/978-1-59745-102-4_35] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Double-stranded DNA (dsDNA) viruses of plants are believed to be plant pararetroviruses. Their genome is replicated by reverse transcription of a larger than unit-length terminally redundant RNA transcript of the viral genomic DNA using the virus-encoded replicase. In order to produce a cloned, infectious viral genome, the clone must be constructed in a binary vector and be longer than the full, unit-length viral genome. The clone can then be transferred by Agrobacterium-assisted inoculation into a suitable host plant to induce virus infection.
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Affiliation(s)
- Qi Huang
- Floral and Nursery Plants Research Unit, U.S. National Arboretum, U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD, USA
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31
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Abstract
Virus replication can cause extensive rearrangement of host cell cytoskeletal and membrane compartments leading to the “cytopathic effect” that has been the hallmark of virus infection in tissue culture for many years. Recent studies are beginning to redefine these signs of viral infection in terms of specific effects of viruses on cellular processes. In this chapter, these concepts have been illustrated by describing the replication sites produced by many different viruses. In many cases, the cellular rearrangements caused during virus infection lead to the construction of sophisticated platforms in the cell that concentrate replicase proteins, virus genomes, and host proteins required for replication, and thereby increase the efficiency of replication. Interestingly, these same structures, called virus factories, virus inclusions, or virosomes, can recruit host components that are associated with cellular defences against infection and cell stress. It is possible that cellular defence pathways can be subverted by viruses to generate sites of replication. The recruitment of cellular membranes and cytoskeleton to generate virus replication sites can also benefit viruses in other ways. Disruption of cellular membranes can, for example, slow the transport of immunomodulatory proteins to the surface of infected cells and protect against innate and acquired immune responses, and rearrangements to cytoskeleton can facilitate virus release.
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Affiliation(s)
- Christopher Netherton
- Vaccinology Group, Pirbright Laboratories, Institute for Animal Health, Surrey, United Kingdom
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32
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Joklik WKB. Reminiscences of the early days of getting to know one of man's best friends. J Interferon Cytokine Res 2007; 27:617-22. [PMID: 17784813 DOI: 10.1089/jir.2007.9977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Wolfgang K Bill Joklik
- Department of Pathology, Akron Children's Hospital, and Northeast Ohio Universities College of Medicine, Akron, OH, USA
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33
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Turner PC, Dilling BP, Prins C, Cresawn SG, Moyer RW, Condit RC. Vaccinia virus temperature-sensitive mutants in the A28 gene produce non-infectious virions that bind to cells but are defective in entry. Virology 2007; 366:62-72. [PMID: 17499330 PMCID: PMC2062567 DOI: 10.1016/j.virol.2007.03.060] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Revised: 02/05/2007] [Accepted: 03/12/2007] [Indexed: 10/23/2022]
Abstract
The vaccinia virus temperature-sensitive mutations Cts6 and Cts9 were mapped by marker rescue and DNA sequencing to the A28 gene. Cts6 and Cts9 contain an identical 2-bp deletion truncating the A28 protein and removing the fourth conserved cysteine near the C-terminus. Cts9 mutant virions produced at 40 degrees C were non-infectious and unable to cause cytopathic effect. However, the mutant A28 protein localized to purified mature virions (MV) at 31 degrees C and 40 degrees C. MV of Cts9 produced at 40 degrees C bound to cells but did not enter cells. Low pH treatment of Cts9-infected cells at 18 h p.i. failed to produce fusion from within at 40 degrees C, but gave fusion at 31 degrees C. Adsorption of Cts9 mutant virions to cells followed by low pH treatment showed a defect in fusion from without. The Cts9 phenotype suggests that the A28 protein is involved in both virus entry and cell-cell fusion, and supports the linkage between the two processes.
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Affiliation(s)
- Peter C Turner
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610-0266, USA.
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34
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Khan M, La Scola B, Lepidi H, Raoult D. Pneumonia in mice inoculated experimentally with Acanthamoeba polyphaga mimivirus. Microb Pathog 2007; 42:56-61. [PMID: 17188457 DOI: 10.1016/j.micpath.2006.08.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 08/04/2006] [Indexed: 11/21/2022]
Abstract
In an attempt to elucidate whether Acanthamoeba polyphaga mimivirus (APM) was pathogenic (i.e., induces histological evidence of inflammation or tissue destruction or both) in mammalian host, we inoculated adult BALB/c (n=6) and C57BL/6 (n=6) mice with APM via intracardiac route. C57BL/6 mice developed histopathological features of pneumonia by post-inoculation day (PID) 3 and BALB/c mice, by PID7. The histopathological features of pneumonia, characterized by the presence of thickened alveolar walls with cellular infiltrates comprising mononuclear leukocytes, macrophages and lymphocytes, diffuse alveolar damages with the formation of hyaline membrane and erythrocytes in the alveolar lumen, were most marked by PID 7. We conclude that APM is pathogenic in mice in experimental conditions.
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Affiliation(s)
- Mohammad Khan
- Unité des Rickettsies, CNRS UMR 6020, IFR 48, Faculté de Médecine, Université de la Méditerranée, 27 Boulevard Jean Moulin, 13385 Marseille 5, France
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35
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Lawrence JE, Brussaard CPD, Suttle CA. Virus-specific responses of Heterosigma akashiwo to infection. Appl Environ Microbiol 2006; 72:7829-34. [PMID: 17041155 PMCID: PMC1694243 DOI: 10.1128/aem.01207-06] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Accepted: 10/05/2006] [Indexed: 11/20/2022] Open
Abstract
We used flow cytometry to examine the process of cell death in the bloom-forming alga Heterosigma akashiwo during infection by a double-stranded DNA virus (OIs1) and a single-stranded RNA virus (H. akashiwo RNA virus [HaRNAV]). These viruses were isolated from the same geographic area and infect the same strain of H. akashiwo. By use of the live/dead stains fluorescein diacetate and SYTOX green as indicators of cellular physiology, cells infected with OIs1 showed signs of infection earlier than HaRNAV-infected cultures (6 to 17 h versus 23 to 29 h). Intracellular esterase activity was lost prior to increased membrane permeability during infection with OIs1, while the opposite was seen with HaRNAV-infected cultures. In addition, OIs1-infected cells accumulated in the cultures while HaRNAV-infected cells rapidly disintegrated. Progeny OIs1 viruses consisted of large and small morphotypes with estimated latent periods of 11 and 17 h, respectively, and about 1,100 and 16,000 viruses produced per cell, respectively. In contrast, HaRNAV produced about 21,000 viruses per cell and had a latent period of 29 h. This study reveals that the characteristics of viral infection in algae are virus dependent and therefore are variable among viruses infecting the same species. This is an important consideration for ecosystem modeling exercises; calculations based on in situ measurements of algal physiology must be sensitive to the diverse responses of algae to viral infection.
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Affiliation(s)
- Janice E Lawrence
- Department of Biology, University of New Brunswick, P.O. Bag Service 45111, Fredericton E3B 6E1, New Brunswick, Canada.
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36
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Langland JO, Cameron JM, Heck MC, Jancovich JK, Jacobs BL. Inhibition of PKR by RNA and DNA viruses. Virus Res 2006; 119:100-10. [PMID: 16704884 DOI: 10.1016/j.virusres.2005.10.014] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2005] [Revised: 09/28/2005] [Accepted: 10/20/2005] [Indexed: 11/28/2022]
Abstract
Interferons were the first of the anti-viral innate immune modulators to be characterized, initially characterized solely as anti-viral proteins [reviewed in Le Page, C., Genin, P., Baines, M.G., Hiscott, J., 2000. Inteferon activation and innate immunity. Rev. Immunogenet. 2, 374-386]. As we have progressed in our understanding of the interferons they have taken a more central role in our understanding of innate immunity and its interplay with the adaptive immune response. One of the key players in function of interferon is the interferon-inducible enzyme, protein kinase (PKR, activatable by RNA). The key role played by PKR in the innate response to virus infection is emphasized by the large number of viruses, DNA viruses as well as RNA viruses, whose hosts range from insects to humans, that code for PKR inhibitors. In this review we will first describe activation of PKR and then describe the myriad of ways that viruses inhibit function of PKR.
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Affiliation(s)
- Jeffrey O Langland
- Center for Infectious Disease and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ 85287-5401, USA
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37
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Abstract
ND10 are small nuclear substructures that are defined by the presence the promyelocytic leukaemia protein PML. Many other proteins have been detected within ND10, a complexity that is reflected in reports of their involvement in multiple cellular pathways that include the regulation of gene expression, chromatin dynamics, protein modification, apoptosis, p53 function, senescence, DNA repair, the interferon response and viral infection. This review summarizes recent evidence of similarities between the behaviour of ND10 components and DNA repair pathway proteins in response to viral infection and DNA damage. ND10 structures become associated with the parental genomes and early replication compartments of many DNA viruses, and DNA repair pathway proteins are also recruited to these sites. Similarly, PML and DNA repair proteins are recruited to sites of DNA damage. The mechanisms by which these events might occur, and the implications for ND10 function in DNA virus infection and chromatin metabolism, are discussed.
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Affiliation(s)
- Roger D Everett
- MRC Virology Unit, Church Street, Glasgow G11 5JR, Scotland, UK.
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38
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Abstract
DNA viruses have enormous utility in cancer research, both as tools for tumor target discovery as well as agents for lytic cancer therapies. This is because there is a profound functional overlap between the DNA viral and tumor cell programs. DNA viruses encode proteins that elicit growth deregulation in infected cells similar to that engendered by mutations in tumor cells. Evolution has refined viral proteins to target the critical cellular hubs that regulate growth. Thus, viral proteins are discriminating biochemical probes that can be used to identify and characterize novel tumor targets. Moreover, the overlap between the DNA viral and tumor programs can also be exploited for the development of lytic cancer therapies. Discovering whether tumor cells selectively complement the replication of viral mutants can reveal novel oncolytic viral therapies, as well as unexpected tumor properties. For example, altered RNA export was recently uncovered as a novel tumor cell property that underlies ONYX-015 replication, a promising oncolytic adenoviral therapy. A perspective is provided on how adenovirus could be systematically exploited to map the requisite role, or indeed the redundancy, of cellular pathways that act in an integrated program to elicit pathological replication. This knowledge has important applications for the rational design of the next generation of oncolytic viruses, as well as the discovery of efficacious combination cancer therapies.
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Affiliation(s)
- Clodagh C O'Shea
- Cancer Research Institute, University of California San Francisco, 94115, USA.
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39
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Abstract
It has been 9 years since the beginning of the first clinical trial in which an oncolytic virus was administered to cancer patients. Since then, oncolytic viruses from five different species have been taken to phase I and II clinical trials in over 300 cancer patients. While additional studies will be required to ascertain if the efficacy of any of these agents is high enough to warrant adding them to the existing therapeutic regimen, it has been reassuring that DNA viruses engineered to achieve tumor selectivity and RNA viruses with relative inherent natural tumor selectivity have proven reasonably safe at the wide range of doses that were tested. Here, we review the biology and clinical results of these five species of viruses and discuss lessons learned and challenges for the future.
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Affiliation(s)
- Manish Aghi
- Department of Neurosurgery, Massachusetts General Hospital, White Building Room 502, 02114, USA.
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40
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Bright Singh IS, Manjusha M, Pai SS, Philip R. Fenneropenaeus indicus is protected from white spot disease by oral administration of inactivated white spot syndrome virus. Dis Aquat Organ 2005; 66:265-70. [PMID: 16261942 DOI: 10.3354/dao066265] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Fenneropenaeus indicus could be protected from white spot disease (WSD) caused by white spot syndrome virus (WSSV) using a formalin-inactivated viral preparation (IVP) derived from WSSV-infected shrimp tissue. The lowest test quantity of lyophilized IVP coated onto feed at 0.025 g(-1) (dry weight) and administered at a rate of 0.035 g feed g(-1) body weight d(-1) for 7 consecutive days was sufficient to provide protection from WSD for a short period (10 d after cessation of IVP administration). Shrimp that survived challenges on the 5th and 10th days after cessation of IVP administration survived repeated challenges although they were sometimes positive for the presence of WSSV by a polymerase chain reaction (PCR) assay specific for WSSV. These results suggest that F. indicus can be protected from WSD by simple oral administration of IVP.
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Affiliation(s)
- I S Bright Singh
- Centre for Fish Disease Diagnosis and Management, Cochin University of Science and Technology, Lakeside Campus, Kerala, India.
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41
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Abstract
Diatoms are a major phytoplankton group that play important roles in maintaining oxygen levels in the atmosphere and sustaining the primary nutritional production of the aquatic environment. Among diatoms, the genus Chaetoceros is one of the most abundant and widespread. Temperature, climate, salinity, nutrients, and predators were regarded as important factors controlling the abundance and population dynamics of diatoms. Here we show that a viral infection can occur in the genus Chaetoceros and should therefore be considered as a potential mortality source. Chaetoceros salsugineum nuclear inclusion virus (CsNIV) is a 38-nm icosahedral virus that replicates within the nucleus of C. salsugineum. The latent period was estimated to be between 12 and 24 h, with a burst size of 325 infectious units per host cell. CsNIV has a genome structure unlike that of other viruses that have been described. It consists of a single molecule of covalently closed circular single-stranded DNA (ssDNA; 6,005 nucleotides), as well as a segment of linear ssDNA (997 nucleotides). The linear segment is complementary to a portion of the closed circle creating a partially double-stranded genome. Sequence analysis reveals a low but significant similarity to the replicase of circoviruses that have a covalently closed circular ssDNA genome. This new host-virus system will be useful for investigating the ecological relationships between bloom-forming diatoms and other viruses in the marine system. Our study supports the view that, given the diversity and abundance of plankton, the ocean is a treasury of undiscovered viruses.
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Affiliation(s)
- Keizo Nagasaki
- Harmful Algal Bloom Division, National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, 2-17-5 Maruishi, Ohno, Saeki, Hiroshima 739-0452, Japan.
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42
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Abstract
A sequence-independent PCR amplification method was used to identify viral nucleic acids in the plasma samples of 25 individuals presenting with symptoms of acute viral infection following high-risk behavior for human immunodeficiency virus type 1 transmission. GB virus C/hepatitis G virus was identified in three individuals and hepatitis B virus in one individual. Three previously undescribed DNA viruses were also detected, a parvovirus and two viruses related to TT virus (TTV). Nucleic acids in human plasma that were distantly related to bacterial sequences or with no detectable similarities to known sequences were also found. Nearly complete viral genome sequencing and phylogenetic analysis confirmed the presence of a new parvovirus distinct from known human and animal parvoviruses and of two related TTV-like viruses highly divergent from both the TTV and TTV-like minivirus groups. The detection of two previously undescribed viral species in a small group of individuals presenting acute viral syndrome with unknown etiology indicates that a rich yield of new human viruses may be readily identifiable using simple methods of sequence-independent nucleic acid amplification and limited sequencing.
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Affiliation(s)
- Morris S Jones
- Blood Systems Research Institute, 270 Masonic Ave., San Francisco, California 94118, USA
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43
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Hutoran M, Ronen A, Perelberg A, Ilouze M, Dishon A, Bejerano I, Chen N, Kotler M. Description of an as yet unclassified DNA virus from diseased Cyprinus carpio species. J Virol 2005; 79:1983-91. [PMID: 15681400 PMCID: PMC546595 DOI: 10.1128/jvi.79.4.1983-1991.2005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Numerous deaths of koi and common carp (Cyprinus carpio) were observed on many farms throughout Israel, resulting in severe financial losses. The lethal viral disease observed is highly contagious and extremely virulent, but morbidity and mortality are restricted to koi and common carp populations. Diseased fish exhibit fatigue and gasping movements in shallow water. Infected fish had interstitial nephritis and gill necrosis as well as petechial hemorrhages in the liver and other symptoms that were not consistent with viral disease, suggesting a secondary infection. Here we report the isolation of carp nephritis and gill necrosis virus (CNGV), which is the etiologic agent of this disease. The virus propagates and induces severe cytopathic effects by 5 days postinfection in fresh koi or carp fin cell cultures (KFC and CFC, respectively), but not in epithelioma papillosum cyprini cells. The virus harvested from KFC cultures induced the same clinical signs, with a mortality of 75 to 95%, upon inoculation into naive koi and common carp. Using PCR, we provide final proof that the isolated virus is indeed the etiologic agent of food and ornamental carp mortalities in fish husbandry. Electron microscopy revealed viral cores with icosahedral morphology of 100 to 110 nm that resembled herpesviruses. Electron micrographs of purified pelleted CNGV sections, together with viral sensitivities to ether and Triton X-100, suggested that it is an enveloped virus. However, the genome of the isolated virus is a double-stranded DNA (dsDNA) molecule of 270 to 290 kbp, which is larger than known herpesviruses. The viral DNA seems highly divergent and bears only small fragments (16 to 45 bp) that are similar to the genomes of several DNA viruses. Nevertheless, amino acid sequences encoded by CNGV DNA fragments bear similarities primarily to members of the Poxviridae and Herpesviridae and to other large dsDNA viruses. We suggest, therefore, that the etiologic agent of this disease may represent an as yet unclassified virus species that is endemic in C. carpio (carp).
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Affiliation(s)
- Marina Hutoran
- Department of Pathology, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel
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44
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Nagasaki K, Shirai Y, Tomaru Y, Nishida K, Pietrokovski S. Algal viruses with distinct intraspecies host specificities include identical intein elements. Appl Environ Microbiol 2005; 71:3599-607. [PMID: 16000767 PMCID: PMC1169056 DOI: 10.1128/aem.71.7.3599-3607.2005] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Accepted: 01/20/2005] [Indexed: 11/20/2022] Open
Abstract
Heterosigma akashiwo virus (HaV) is a large double-stranded DNA virus infecting the single-cell bloom-forming raphidophyte (golden brown alga) H. akashiwo. A molecular phylogenetic sequence analysis of HaV DNA polymerase showed that it forms a sister group with Phycodnaviridae algal viruses. All 10 examined HaV strains, which had distinct intraspecies host specificities, included an intein (protein intron) in their DNA polymerase genes. The 232-amino-acid inteins differed from each other by no more than a single nucleotide change. All inteins were present at the same conserved position, coding for an active-site motif, which also includes inteins in mimivirus (a very large double-stranded DNA virus of amoebae) and in several archaeal DNA polymerase genes. The HaV intein is closely related to the mimivirus intein, and both are apparently monophyletic to the archaeal inteins. These observations suggest the occurrence of horizontal transfers of inteins between viruses of different families and between archaea and viruses and reveal that viruses might be reservoirs and intermediates in horizontal transmissions of inteins. The homing endonuclease domain of the HaV intein alleles is mostly deleted. The mechanism keeping their sequences basically identical in HaV strains specific for different hosts is yet unknown. One possibility is that rapid and local changes in the HaV genome change its host specificity. This is the first report of inteins found in viruses infecting eukaryotic algae.
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Affiliation(s)
- Keizo Nagasaki
- National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, Hiroshima, Japan
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45
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Abstract
Human tumor suppressor protein p53 plays a major role in the cell cycle, orchestrating a number of important genes involved in cell-cycle control and apoptosis, and seems to be one of the most important molecules protecting cells from malignant transformation. Mutations in the p53 gene are observed in about 50% of primary tumors, inducing defective p53 protein no longer capable of binding DNA and of activating transcription. Certain DNA viruses are thought to act in a similar way and may also contribute to the progression of invasive cancer in infected tissue. One of the most effective strategies employed by these viruses is the inhibition of p53 protein by interaction with viral oncoproteins, implying a direct but also an indirect role of these viruses in the impairment of p53 structure and function. This article provides a summary of current knowledge concerning p53 tumor suppressor protein and reviews the different mechanisms adopted by different DNA viruses in undermining p53 function.
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Affiliation(s)
- S Collot-Teixeira
- Department of Virology, Limoges University Teaching Hospital, CHRU Dupuytren, 2 avenue Martin Luther King, 87042 Limoges, France
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46
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Tsai JM, Wang HC, Leu JH, Hsiao HH, Wang AHJ, Kou GH, Lo CF. Genomic and proteomic analysis of thirty-nine structural proteins of shrimp white spot syndrome virus. J Virol 2004; 78:11360-70. [PMID: 15452257 PMCID: PMC521807 DOI: 10.1128/jvi.78.20.11360-11370.2004] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
White spot syndrome virus (WSSV) virions were purified from the hemolymph of experimentally infected crayfish Procambarus clarkii, and their proteins were separated by 8 to 18% gradient sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to give a protein profile. The visible bands were then excised from the gel, and following trypsin digestion of the reduced and alkylated WSSV proteins in the bands, the peptide sequence of each fragment was determined by liquid chromatography-nano-electrospray ionization tandem mass spectrometry (LC-nanoESI-MS/MS) using a quadrupole/time-of-flight mass spectrometer. Comparison of the resulting peptide sequence data against the nonredundant database at the National Center for Biotechnology Information identified 33 WSSV structural genes, 20 of which are reported here for the first time. Since there were six other known WSSV structural proteins that could not be identified from the SDS-PAGE bands, there must therefore be a total of at least 39 (33 + 6) WSSV structural protein genes. Only 61.5% of the WSSV structural genes have a polyadenylation signal, and preliminary analysis by 3' rapid amplification of cDNA ends suggested that some structural protein genes produced mRNA without a poly(A) tail. Microarray analysis showed that gene expression started at 2, 6, 8, 12, 18, 24, and 36 hpi for 7, 1, 4, 12, 9, 5, and 1 of the genes, respectively. Based on similarities in their time course expression patterns, a clustering algorithm was used to group the WSSV structural genes into four clusters. Genes that putatively had common or similar roles in the viral infection cycle tended to appear in the same cluster.
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Affiliation(s)
- Jyh-Ming Tsai
- Graduate Institute of Zoology, National Taiwan University, Taipei 106, Taiwan R.O.C
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47
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Park JH, Seok SH, Cho SA, Baek MW, Lee HY, Kim DJ, Kim HY, Chang SO, Park JH. Safety and protective effect of a disinfectant (STEL water) for white spot syndrome viral infection in shrimp. Dis Aquat Organ 2004; 60:253-257. [PMID: 15521325 DOI: 10.3354/dao060253] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The efficacy of STEL water for protection against white spot syndrome virus (WSSV) infection was evaluated using shrimp. The LC50 of residual chlorine (Cl-) in STEL water for brood-stock and 2-mo-old shrimp were 2.3 and 3.2 ppm, respectively. All 2-month-old shrimp raised in seawater containing more than 40 microl 2l(-1) of a WSSV-infected tissue homogenate died within 3 d post-exposure (dpe). Thus, a 10-fold dose of 400 microl 2 l(-1) was used in the disinfection tests. Low concentrations of STEL water effectively prevented mortality of shrimp at this challenge dose. All 2-month-old shrimp exposed to seawater with 400 microl of viral homogenate disinfected with STEL water at Cl- concentrations over 0.125 ppm for 1 and 10 min, lived until 5 dpe. With 5-mo-old shrimp, all positive control shrimps died within 3 dpe, whereas most shrimp reared in seawater disinfected with STEL water for 1 h before addition of homogenate lived until 5 dpe. Results suggested that continuous disinfection of seawater with STEL water may be effective for preventing WSSV infection in shrimp.
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Affiliation(s)
- Jong-Hwan Park
- Department of Laboratory Animal Medicine, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea
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Jiravanichpaisal P, Söderhäll K, Söderhäll I. Effect of water temperature on the immune response and infectivity pattern of white spot syndrome virus (WSSV) in freshwater crayfish. Fish Shellfish Immunol 2004; 17:265-275. [PMID: 15276606 DOI: 10.1016/j.fsi.2004.03.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Revised: 03/04/2004] [Accepted: 03/29/2004] [Indexed: 05/24/2023]
Abstract
The susceptibility of two species of freshwater crayfish, Pacifastacus leniusculus and Astacus astacus, to white spot syndrome virus (WSSV) by intramuscular injection was compared and the results show that both species are susceptible to WSSV. The effect of water temperature on the development of white spot disease in crayfish was also studied. Crayfish were exposed to different temperatures after WSSV injection or oral exposure and the mortalities were recorded over a period of 45 days. No mortality was observed when crayfish were held at 4+/-2 degrees C or 12+/-2 degrees C and reached 100% when these crayfish transferred to 22+/-2 degrees C. The mortalities of nearly moribund crayfish at 22+/-2 degrees C with WSSV could be delayed after transfer to temperature below 16 degrees C. These results clearly show that low temperature affects the WSSV pathogenicity in crayfish. Moreover, haemocyte counts, phenoloxidase activity, mRNA levels of prophenoloxidase (proPO) and the lipopolysaccharide and beta-1,3-glucan binding protein (LGBP) in crayfish exposed to various water temperatures were studied. Total haemocyte and granular cell counts of crayfish held at different temperatures were not significantly (P>0.05) different, except for the total haemocyte number at 18 degrees C was significantly (P<0.05) higher than in crayfish at 4 degrees C. The percentage of granular cells in crayfish held at 4 degrees C was the highest compared to crayfish maintained at other temperatures. The phenoloxidase activities in haemocyte lysate supernatant (HLS) of crayfish at all temperature groups remained similar. The amount of proPO-mRNAs in haemocytes was much higher than the amount of LGBP-m RNAs in all the experimental groups. However, there was no change in the level of pro PO-mRNA at the tested temperatures. Interestingly, the level of LGBP-mRNA of crayfish kept at 22 degrees C was much lower than in those held at lower temperatures. Proliferation of the haematopoietic tissues was higher at high temperatures which may support replication of WSSV, and explain the high mortality of crayfish with WSSV infection at high temperature. Based on these studies it is concluded that crayfish might act as a carrier of WSSV at low water temperature and could develop white spot disease if the water temperature is increased.
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Affiliation(s)
- Pikul Jiravanichpaisal
- Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden
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49
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Edgerton BF. Susceptibility of the Australian freshwater crayfish Cherax destructor albidus to white spot syndrome virus (WSSV). Dis Aquat Organ 2004; 59:187-193. [PMID: 15264714 DOI: 10.3354/dao059187] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Cherax destructor occurs naturally and/or is farmed in all Australian mainland states and territories and is of major cultural, economical and conservation significance. The aim of this study was to determine susceptibility of the commercially important subspecies C. destructor albidus to white spot syndrome virus (WSSV), a hazard to crustaceans and currently considered to be exotic to Australia. In challenge tests by intramuscular injection, C. destructor albidus displayed a similar level of susceptibility to white spot disease (WSD) as Penaeus monodon (i.e. 100% mortality in 3 d). In one oral challenge test where C. destructor albidus was subjected to significant temperature stress, over 50% died of severe WSD within 14 d post challenge. All dead and moribund crayfish displayed histopathological lesions typical for WSD and gave positive results for WSSV in DNA dot blot hybridization tests. Survivors to 30 d (n = 3) showed no lesions and gave negative dot blot test results. In a second oral challenge test without temperature stress, mortality was delayed but reached 75% by 30 d. However, no typical WSD lesions were observed in the dead, dying or surviving crayfish and dot blot test results were negative. The results suggested that C. destructor albidus would be less susceptible than P. monodon to WSSV exposure via natural routes of infection in farms and in the wild. This information may be useful for disease import risk analysis for WSSV.
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Affiliation(s)
- Brett F Edgerton
- Centre for Marine Studies, University of Queensland, St Lucia, Queensland 4072, Australia.
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50
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Abstract
Mammalian cells respond to virus infections by eliciting both innate and adaptive immune responses. One of the most effective innate antiviral responses is the production of alpha/beta interferon and the subsequent induction of interferon-stimulated genes (ISGs), whose products collectively limit virus replication and spread. Following viral infection, interferon is produced in a biphasic fashion that involves a number of transcription factors, including the interferon regulatory factors (IRFs) 1, 3, 7, and 9. In addition, virus infection has been shown to directly induce ISGs in the absence of prior interferon production through the activation of IRF3. This process is believed to require virus replication and results in IRF3 hyperphosphorylation, nuclear localization, and proteasome-mediated degradation. Previously, we and others demonstrated that herpes simplex virus type 1 (HSV-1) induces ISGs and an antiviral response in fibroblasts in the absence of both interferon production and virus replication. In this report, we show that the entry of enveloped virus particles from diverse virus families elicits a similar innate response. This process requires IRF3, but not IRF1, IRF7, or IRF9. Following virus replication, the large DNA viruses HSV-1 and vaccinia virus effectively inhibit ISG mRNA accumulation, whereas the small RNA viruses Newcastle disease virus, Sendai virus, and vesicular stomatitis virus do not. In addition, we found that IRF3 hyperphosphorylation and degradation do not correlate with ISG and antiviral state induction but instead serve as a hallmark of productive virus replication, particularly following a high-multiplicity infection. Collectively, these data suggest that virus entry triggers an innate antiviral response mediated by IRF3 and that subsequent virus replication results in posttranslational modification of IRF3, such as hyperphosphorylation, depending on the nature of the incoming virus.
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Affiliation(s)
- Susan E Collins
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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