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Andrew J Davison - One of the best experts on this subject based on the ideXlab platform.
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create nine new species in the family herpesviridae Herpesvirales
2021Co-Authors: Mária Benko, Andrew J Davison, Andor Doszpoly, Akbar Dastjerdi, Daniel P. Depledge, Curtis R Brandt, Neil A Bryant, Derek Gatherer, U A Gompels, Carol A. HartleyAbstract:These proposals are made on the basis of a phylogenetic analysis of six well-conserved viral genes. The proposed species are: Cacatuid alphaherpesvirus 2 and Psittacid alphaherpesvirus 5 in genus Iltovirus, Macropodid alphaherpesvirus 4 and Pteropodid alphaherpesvirus 2 in genus Simplexvirus, and Equid alphaherpesvirus 6 in genus Varicellovirus (in subfamily Alphaherpesvirinae); Elephantid betaherpesvirus 3 in genus Proboscivirus (in subfamily Betaherpesvirinae); and Macacine gammaherpesvirus 13 in genus Lymphocryptovirus, Rhinolophid gammaherpesvirus 1 in genus Percavirus, and Colobine gammaherpesvirus 1 in genus Rhadinovirus (in subfamily Gammaherpesvirinae).
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Herpesvirus systematics.
Veterinary microbiology, 2010Co-Authors: Andrew J DavisonAbstract:This paper is about the taxonomy and genomics of herpesviruses. Each theme is presented as a digest of current information flanked by commentaries on past activities and future directions. The International Committee on Taxonomy of Viruses recently instituted a major update of herpesvirus classification. The former family Herpesviridae was elevated to a new order, the Herpesvirales, which now accommodates 3 families, 3 subfamilies, 17 genera and 90 species. Future developments will include revisiting the herpesvirus species definition and the criteria used for taxonomic assignment, particularly in regard to the possibilities of classifying the large number of herpesviruses detected only as DNA sequences by polymerase chain reaction. Nucleotide sequence accessions in primary databases, such as GenBank, consist of the sequences plus annotations of the genetic features. The quality of these accessions is important because they provide a knowledge base that is used widely by the research community. However, updating the accessions to take account of improved knowledge is essentially reserved to the original depositors, and this activity is rarely undertaken. Thus, the primary databases are likely to become antiquated. In contrast, secondary databases are open to curation by experts other than the original depositors, thus increasing the likelihood that they will remain up to date. One of the most promising secondary databases is RefSeq, which aims to furnish the best available annotations for complete genome sequences. Progress in regard to improving the RefSeq herpesvirus accessions is discussed, and insights into particular aspects of herpesvirus genomics arising from this work are reported.
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Phylogenetic relationships in the family Alloherpesviridae.
Diseases of Aquatic Organisms, 2009Co-Authors: Thomas B Waltzek, Garry O. Kelley, Michael E Alfaro, Tomofumi Kurobe, Andrew J Davison, Ronald P HedrickAbstract:Phylogenetic relationships among herpesviruses (HVs) of mammals, birds, and reptiles have been studied extensively, whereas those among other HVs are relatively unexplored. We have reconstructed the phylogenetic relationships among 13 fish and amphibian HVs using maximum likelihood and Bayesian analyses of amino acid sequences predicted from parts of the DNA polymerase and terminase genes. The relationships among 6 of these viruses were confirmed using the partial DNA polymerase data plus the complete sequences of the terminase, helicase, and triplex protein genes; the position of these viruses among all other sequenced HVs was also investigated using the complete terminase gene. The results established the monophyly of the fish and amphibian HVs (Alloherpesviridae) separate from the HVs of mammals, birds, and reptiles (Herpesviridae) and the single recognized HV of bivalve mollusks (Malacoherpesviridae) in the order Herpesvirales. Two major clades in the family Alloherpesviridae were recognized: one consisting of viruses from cyprinid and anguillid hosts and the other of viruses from ictalurid, salmonid, acipenserid, and ranid hosts. A comparison of virus and host phylogenies suggested that closely related HVs in this family may have coevolved with their hosts, whereas significant codiversification was not apparent for the more distantly related viruses.
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The order Herpesvirales
Archives of Virology, 2009Co-Authors: Andrew J Davison, Bernhard Ehlers, Anthony C. Minson, Richard Eberle, Philip E. Pellett, Michael J. Studdert, Gary S. Hayward, Bernard Roizman, Etienne ThiryAbstract:The taxonomy of herpesviruses has been updated by the International Committee on Taxonomy of Viruses (ICTV). The former family Herpesviridae has been split into three families, which have been incorporated into the new order Herpesvirales . The revised family Herpesviridae retains the mammal, bird and reptile viruses, the new family Alloherpesviridae incorporates the fish and frog viruses, and the new family Malacoherpesviridae contains a bivalve virus. Three new genera have been created in the family Herpesviridae , namely Proboscivirus in the subfamily Betaherpesvirinae and Macavirus and Percavirus in the subfamily Gammaherpesvirinae . These genera have been formed by the transfer of species from established genera and the erection of new species, and other new species have been added to some of the established genera. In addition, the names of some nonhuman primate virus species have been changed. The family Alloherpesviridae has been populated by transfer of the genus Ictalurivirus and addition of the new species Cyprinid herpesvirus 3 . The family Malacoherpesviridae incorporates the new genus Ostreavirus containing the new species Ostreid herpesvirus 1 .
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Molecular Evolution of the Herpesvirales
Origin and Evolution of Viruses, 2008Co-Authors: Andrew J Davison, Aidan Dolan, Edgar E. Sevilla-reyesAbstract:The herpesviruses are a group of large DNA viruses, originally defined by their characteristic virion structure. On the basis of genome sequences they have been assigned to an order, Herpesvirales, containing three families: the Herpesviridae, infecting mammals, birds and reptiles; the Alloherpesviridae, infecting amphibians and fish; and the Malacoherpesviridae, populated only by an oyster virus. Viruses in the Herpesviridae are descended from a common ancestor, as are those in the Alloherpesviridae, but connections between the families are tenuous.The Herpesviridae include eight human viruses. Three widely diverged subfamilies, the Alpha -, Beta -, and Gammaherpesvirinae, are defined. A robust phylogenetic tree has been constructed for this family, based on amino acid sequences from conserved genes. Within sub-families, aspects of branching patterns resemble those of mammalian host lineages, indicating long-term co-evolution of virus and host lines and thus enabling inference of a timeframe for the tree. On this basis the tree is estimated to be about 400 million years in depth. Some 40 genes are conserved across the Herpesviridae, with recognized roles mainly in capsid structure and DNA replication machinery. Functions of non-conserved genes include roles in immune modulation and latency. Some herpesvirus genes appear to have originated by capture from cellular genomes, and others by genesis de novo. Multigene families are common, notably in the Betaherpesvirinae. Aspects of DNA replication systems have diverged among subfamilies, with complex arrangements for initiation of DNA synthesis in the Gammaherpesvirinae and part of the Betaherpesvirinae, and disabling in the Betaherpesvirinae ofgenes for nucleotide anabolism. Comparative genomic sequenc-ing of herpesvirus isolates is revealing novel aspects of recent evolution. Recombination among strains has emerged as a general phenomenon. Also, certain latent cycle genes of gammaherpesviruses uniquely evince signs of widespread diversifying selection. Genomic organizations in theAlloherpes-viridae and Malacoherpesviridae look gener-ally similar to those of the Herpesviridae, and the Alloherpesviridae are also widely diverse.
Alain Vanderplasschen - One of the best experts on this subject based on the ideXlab platform.
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L’HERPÈSVIRUS CYPRIN 3: UN VIRUS INTÉRESSANT TANT POUR
2016Co-Authors: Appliquée Que, La Recherche, Par Guillaume Fournier, Alain VanderplasschenAbstract:(Communication présentée le 3 novembre 2011) L’herpèsvirus de la carpe koi, récemment renommé herpèsvirus cyprin 3 (CyHV-3), est l’agent causal d’une maladie émergente et fatale chez la carpe commune et la carpe koi. Depuis son émergence fin des années 1990, ce pathogène très contagieux a induit des pertes économiques très importantes dans l’élevage industriel des carpes koi et commune. En plus de son intérêt économique, des études récentes démontrent l’intérêt du CyHV-3 comme sujet de recherche fondamentale: par exemple, de par la taille de son génome (le plus grand au sein de l’ordre des Herpesvirales), le CyHV-3 procure un modèle extrême pour l’étude de la mutagenèse des grands virus à ADN. Par ailleurs, l’étude de la porte d’entrée de ce virus chez la carpe suggère que la peau des poissons téléostéens pourrait repré-senter une porte d’entrée efficace pour certains virus. Le modèle « CyHV-3- carpe » a également permis de démontrer de manière directe le rôle du mucus épidermique comme composant de l’immunité innée. Dans ce manuscrit, nous résumons les études fondamentales relatives à ces aspects de la recherche sur le CyHV-3
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cyprinid herpesvirus 3
Emerging Infectious Diseases, 2010Co-Authors: Benjamin Michel, Guillaume Fournier, Francois Lieffrig, Berenice Costes, Alain VanderplasschenAbstract:The recently designated cyprinid herpesvirus 3 (CyHV-3) is an emerging agent that causes fatal disease in common and koi carp. Since its emergence in the late 1990s, this highly contagious pathogen has caused severe financial losses in common and koi carp culture industries worldwide. In addition to its economic role, recent studies suggest that CyHV-3 may have a role in fundamental research. CyHV-3 has the largest genome among viruses in the order Herpesvirales and serves as a model for mutagenesis of large DNA viruses. Other studies suggest that the skin of teleost fish represents an efficient portal of entry for certain viruses. The effect of temperature on viral replication suggests that the body temperature of its poikilotherm host could regulate the outcome of the infection (replicative vs. nonreplicative). Recent advances with regard to CyHV-3 provide a role for this virus in fundamental and applied research.
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the genome of cyprinid herpesvirus 3 encodes 40 proteins incorporated in mature virions
Journal of General Virology, 2010Co-Authors: Benjamin Michel, Francois Lieffrig, Alain Vanderplasschen, Baptiste Leroy, Stalin V Raj, Jan Mast, Ruddy Wattiez, Berenice CostesAbstract:Koi herpesvirus, also known as cyprinid herpesvirus 3 (CyHV-3), is the aetiological agent of an emerging and mortal disease in common and koi carp. CyHV-3 virions present the characteristic morphology of other members of the order Herpesvirales, being composed of an envelope, a capsid containing the genome and a tegument. This study identified CyHV-3 structural proteins and the corresponding encoding genes using liquid chromatography tandem mass spectrometry-based proteomic approaches. In addition, exponentially modified protein abundance index analyses were used to estimate the relative abundance of the identified proteins in CyHV-3 virions. These analyses resulted in the identification of 40 structural proteins, which were classified based on bioinformatic analyses as capsid (three), envelope (13), tegument (two) and unclassified (22) structural proteins. Finally, a search for host proteins in purified CyHV-3 virions indicated the potential incorporation of up to 18 distinct cellular proteins. The identification of the proteins incorporated into CyHV-3 virions and determination of the viral genes encoding these proteins are key milestones for further fundamental and applied research on this virus.
Sylvie Lapègue - One of the best experts on this subject based on the ideXlab platform.
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Genotyping of a microsatellite locus to differentiate clinical Ostreid herpesvirus 1 specimens
Veterinary Research, 2014Co-Authors: Tristan Renault, Gwenaëlle Tchaleu, Nicole Faury, Pierrick Moreau, Amélie Segarra, Valérie Barbosa-solomieu, Sylvie LapègueAbstract:Ostreid herpesvirus 1 (OsHV-1) is a DNA virus belonging to the Malacoherpesviridae family from the Herpesvirales order. OsHV-1 has been associated with mortality outbreaks in different bivalve species including the Pacific cupped oyster, Crassostrea gigas . Since 2008, massive mortality events have been reported among C. gigas in Europe in relation to the detection of a variant of OsHV-1, called μVar. Since 2009, this variant has been mainly detected in France. These results raise questions about the emergence and the virulence of this variant. The search for association between specific virus genetic markers and clinical symptoms is of great interest and the characterization of the genetic variability of OsHV-1 specimens is an area of growing interest. Determination of nucleotide sequences of PCR-amplified virus DNA fragments has already been used to characterize OsHV-1 specimens and virus variants have thus been described. However, the virus DNA sequencing approach is time-consuming in the high-scale format. Identification and genotyping of highly polymorphic microsatellite loci appear as a suitable approach. The main objective of the present study was the development of a genotyping method in order to characterise clinical OsHV-1 specimens by targeting a particular microsatellite locus located in the ORF4 area. Genotyping results were compared to sequences already available. An excellent correlation was found between the detected genotypes and the corresponding sequences showing that the genotyping approach allowed an accuraté discrimination between virus specimens.
Tristan Renault - One of the best experts on this subject based on the ideXlab platform.
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insights on the association between somatic aneuploidy and ostreid herpesvirus 1 detection in the oysters crassostrea gigas c angulata and their f1 hybrids
Aquaculture Research, 2016Co-Authors: Tristan Renault, Jose I Navas, Frederico M Batista, Pierre Boudry, Monserrat Lopezsanmartin, Francisco Ruano, Vera G Fonseca, Alexandra LeitaoAbstract:Cytogenetic abnormalities associated with viral infections, including from viruses of the Herpesvirales order, have been reported in vertebrate species. Ostreid herpesvirus 1 (OsHV-1) has been detected worldwide during mortality outbreaks of the Pacific oyster Crassostrea gigas. On the other hand, a high proportion of aneuploid cells in somatic tissues have been observed in C. gigas. In this study, we analysed the putative association between aneuploidy levels and the detection of OsHV-1 in gills of C. gigas, the Portuguese oyster C. angulata and their F1 hybrids cultured in Ria Formosa (Portugal). OsHV-1 was detected by PCR in 5.4% of the total of oysters analysed (n = 111) namely in 11.1%, 8.0% and 1.7% of C. gigas, C. angulata and F1 hybrid respectively. Sequencing analysis of a viral fragment amplified with the C2/C6 primer pair revealed a high similarity with the OsHV-1 reference type. Moreover, in situ hybridization confirmed the presence of OsHV-1 in gill tissue. Oysters where OsHV-1 was detected had a significantly higher mean percentage of aneuploid cells (25%) than the ones where the virus was not detected (18%). However, the overall low percentage of positive samples contrasted with the high mean percentage of aneuploidy observed, with 50% of the oysters analysed showing a percentage of aneuploid cells between 20% and 30%. We hypothesize that somatic aneuploidy may adversely affect oysters making them more prone to OsHV-1 infection, but the virus is unlikely to be the cause of somatic aneuploidy.
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Genotyping of a microsatellite locus to differentiate clinical Ostreid herpesvirus 1 specimens
Veterinary Research, 2014Co-Authors: Tristan Renault, Gwenaëlle Tchaleu, Nicole Faury, Pierrick Moreau, Amélie Segarra, Valérie Barbosa-solomieu, Sylvie LapègueAbstract:Ostreid herpesvirus 1 (OsHV-1) is a DNA virus belonging to the Malacoherpesviridae family from the Herpesvirales order. OsHV-1 has been associated with mortality outbreaks in different bivalve species including the Pacific cupped oyster, Crassostrea gigas . Since 2008, massive mortality events have been reported among C. gigas in Europe in relation to the detection of a variant of OsHV-1, called μVar. Since 2009, this variant has been mainly detected in France. These results raise questions about the emergence and the virulence of this variant. The search for association between specific virus genetic markers and clinical symptoms is of great interest and the characterization of the genetic variability of OsHV-1 specimens is an area of growing interest. Determination of nucleotide sequences of PCR-amplified virus DNA fragments has already been used to characterize OsHV-1 specimens and virus variants have thus been described. However, the virus DNA sequencing approach is time-consuming in the high-scale format. Identification and genotyping of highly polymorphic microsatellite loci appear as a suitable approach. The main objective of the present study was the development of a genotyping method in order to characterise clinical OsHV-1 specimens by targeting a particular microsatellite locus located in the ORF4 area. Genotyping results were compared to sequences already available. An excellent correlation was found between the detected genotypes and the corresponding sequences showing that the genotyping approach allowed an accuraté discrimination between virus specimens.
Etienne Thiry - One of the best experts on this subject based on the ideXlab platform.
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The order Herpesvirales
Archives of Virology, 2009Co-Authors: Andrew J Davison, Bernhard Ehlers, Anthony C. Minson, Richard Eberle, Philip E. Pellett, Michael J. Studdert, Gary S. Hayward, Bernard Roizman, Etienne ThiryAbstract:The taxonomy of herpesviruses has been updated by the International Committee on Taxonomy of Viruses (ICTV). The former family Herpesviridae has been split into three families, which have been incorporated into the new order Herpesvirales . The revised family Herpesviridae retains the mammal, bird and reptile viruses, the new family Alloherpesviridae incorporates the fish and frog viruses, and the new family Malacoherpesviridae contains a bivalve virus. Three new genera have been created in the family Herpesviridae , namely Proboscivirus in the subfamily Betaherpesvirinae and Macavirus and Percavirus in the subfamily Gammaherpesvirinae . These genera have been formed by the transfer of species from established genera and the erection of new species, and other new species have been added to some of the established genera. In addition, the names of some nonhuman primate virus species have been changed. The family Alloherpesviridae has been populated by transfer of the genus Ictalurivirus and addition of the new species Cyprinid herpesvirus 3 . The family Malacoherpesviridae incorporates the new genus Ostreavirus containing the new species Ostreid herpesvirus 1 .