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1.
J Virol ; 95(19): e0101221, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34260287

RESUMO

Vaccinia virus produces two types of virions known as single-membraned intracellular mature virus (MV) and double-membraned extracellular enveloped virus (EV). EV production peaks earlier when initial MVs are further wrapped and secreted to spread infection within the host. However, late during infection, MVs accumulate intracellularly and become important for host-to-host transmission. The process that regulates this switch remains elusive and is thought to be influenced by host factors. Here, we examined the hypothesis that EV and MV production are regulated by the virus through expression of F13 and the MV-specific protein A26. By switching the promoters and altering the expression kinetics of F13 and A26, we demonstrate that A26 expression downregulates EV production and plaque size, thus limiting viral spread. This process correlates with A26 association with the MV surface protein A27 and exclusion of F13, thus reducing EV titers. Thus, MV maturation is controlled by the abundance of the viral A26 protein, independently of other factors, and is rate limiting for EV production. The A26 gene is conserved within vertebrate poxviruses but is strikingly lost in poxviruses known to be transmitted exclusively by biting arthropods. A26-mediated virus maturation thus has the appearance to be an ancient evolutionary adaptation to enhance transmission of poxviruses that has subsequently been lost from vector-adapted species, for which it may serve as a genetic signature. The existence of virus-regulated mechanisms to produce virions adapted to fulfill different functions represents a novel level of complexity in mammalian viruses with major impacts on evolution, adaptation, and transmission. IMPORTANCE Chordopoxviruses are mammalian viruses that uniquely produce a first type of virion adapted to spread within the host and a second type that enhances transmission between hosts, which can take place by multiple ways, including direct contact, respiratory droplets, oral/fecal routes, or via vectors. Both virion types are important to balance intrahost dissemination and interhost transmission, so virus maturation pathways must be tightly controlled. Here, we provide evidence that the abundance and kinetics of expression of the viral protein A26 regulates this process by preventing formation of the first form and shifting maturation toward the second form. A26 is expressed late after the initial wave of progeny virions is produced, so sufficient viral dissemination is ensured, and A26 provides virions with enhanced environmental stability. Conservation of A26 in all vertebrate poxviruses, but not in those transmitted exclusively via biting arthropods, reveals the importance of A26-controlled virus maturation for transmission routes involving environmental exposure.


Assuntos
Regiões Promotoras Genéticas , Vírus Vaccinia/fisiologia , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Chordopoxvirinae/genética , Chordopoxvirinae/metabolismo , Engenharia Genética , Humanos , Orthopoxvirus/genética , Orthopoxvirus/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Vírus Vaccinia/genética , Ensaio de Placa Viral , Proteínas Virais/genética
2.
Vet Pathol ; 57(2): 296-310, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32096438

RESUMO

Cervidpoxvirus is one of the more recently designated genera within the subfamily Chordopoxvirinae, with Deerpox virus (DPV) as the only recognized species to date. In this study, the authors describe spontaneous disease and infection in the North American moose (Alces americanus) by a novel Cervidpoxvirus, here named Moosepox virus (MPV). Three 4-month-old moose calves developed a multifocal subacute-to-chronic, necrotizing, suppurative-to-granulomatous dermatitis that affected the face and the extremities. Ultrastructurally, all stages of MPV morphogenesis-that is, crescents, spherical immature particles, mature particles, and enveloped mature virus-were observed in skin tissue. In vitro infection with MPV confirmed that its morphogenesis was similar to that of the prototype vaccinia virus. The entire coding region, including 170 putative genes of this MPV, was sequenced and annotated. The sequence length was 164,258 bp with 98.5% nucleotide identity with DPV (strain W-1170-84) based on the whole genome. The genome of the study virus was distinct from that of the reference strain (W-1170-84) in certain genes, including the CD30-like protein (83.9% nucleotide, 81.6% amino acid), the endothelin precursor (73.2% nucleotide including some indels, 51.4% amino acid), and major histocompatibility class (MHC) class I-like protein (81.0% nucleotide, 68.2% amino acid). This study provides biological characterization of a new Cervidpoxvirus attained through in vivo and in vitro ultrastructural analyses. It also demonstrates the importance of whole-genome sequencing in the molecular characterization of poxviruses identified in taxonomically related hosts.


Assuntos
Chordopoxvirinae/genética , Cervos/virologia , Dermatite/veterinária , Genoma Viral/genética , Animais , Chordopoxvirinae/isolamento & purificação , Chordopoxvirinae/ultraestrutura , Dermatite/diagnóstico por imagem , Dermatite/patologia , Dermatite/virologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Pele/patologia , Pele/virologia , Sequenciamento Completo do Genoma/veterinária
3.
Viruses ; 11(12)2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810339

RESUMO

Saltwater crocodilepox virus (SwCRV), belonging to the genus Crocodylidpoxvirus, are large DNA viruses posing an economic risk to Australian saltwater crocodile (Crocodylus porosus) farms by extending production times. Although poxvirus-like particles and sequences have been confirmed, their infection dynamics, inter-farm genetic variability and evolutionary relationships remain largely unknown. In this study, a poxvirus infection dynamics study was conducted on two C. porosus farms. One farm (Farm 2) showed twice the infection rate, and more concerningly, an increase in the number of early- to late-stage poxvirus lesions as crocodiles approached harvest size, reflecting the extended production periods observed on this farm. To determine if there was a genetic basis for this difference, 14 complete SwCRV genomes were isolated from lesions sourced from five Australian farms. They encompassed all the conserved genes when compared to the two previously reported SwCRV genomes and fell within three major clades. Farm 2's SwCRV sequences were distributed across all three clades, highlighting the likely mode of inter-farm transmission. Twenty-four recombination events were detected, with one recombination event resulting in consistent fragmentation of the P4c gene in the majority of the Farm 2 SwCRV isolates. Further investigation into the evolution of poxvirus infection in farmed crocodiles may offer valuable insights in evolution of this viral family and afford the opportunity to obtain crucial information into natural viral selection processes in an in vivo setting.


Assuntos
Jacarés e Crocodilos/virologia , Doenças dos Animais/virologia , Chordopoxvirinae/classificação , Chordopoxvirinae/genética , Evolução Molecular , Genoma Viral , Genômica , Infecções por Poxviridae/veterinária , Sequência de Aminoácidos , Doenças dos Animais/epidemiologia , Animais , Austrália , Genômica/métodos , Filogenia , Prevalência , Recombinação Genética
4.
Viruses ; 11(6)2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248065

RESUMO

Interest in bat-related viruses has increased considerably during the last decade, leading to the discovery of a rising number of new viruses in several bat species. Poxviridae are a large, diverse family of DNA viruses that can infect a wide range of vertebrates and invertebrates. To date, only a few documented detections of poxviruses have been described in bat populations on three different continents (America, Africa, and Australia). These viruses are phylogenetically dissimilar and have diverse clinical impacts on their hosts. Herein, we report the isolation, nearly complete genome sequencing, and annotation of a novel poxvirus detected from an insectivorous bat (Hypsugo savii) in Northern Italy. The virus is tentatively named Hypsugopoxvirus (HYPV) after the bat species from which it was isolated. The nearly complete genome size is 166,600 nt and it encodes 161 genes. Genome analyses suggest that HYPV belongs to the Chordopoxvirinae subfamily, with the highest nucleotide identity (85%) to Eptesipoxvirus (EPTV) detected from a microbat Eptesicus fuscus in WA, USA, in 2011. To date, HYPV represents the first poxvirus detected in bats in Europe; thus, its viral ecology and disease associations should be investigated further.


Assuntos
Quirópteros/virologia , Chordopoxvirinae/classificação , Chordopoxvirinae/isolamento & purificação , Infecções por Poxviridae/veterinária , Animais , Chordopoxvirinae/genética , DNA Viral/química , DNA Viral/genética , Itália , Filogenia , Infecções por Poxviridae/virologia , Análise de Sequência de DNA
5.
Trop Anim Health Prod ; 51(4): 819-829, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30649668

RESUMO

During September and October 2017, a highly fatal outbreak of a disease clinically indistinguishable from goat pox occurred in the villages around the Kaziranga National Park, Assam, India. This was investigated through clinical examination of affected animals, individual interviews with goat keepers and participatory village meetings. Laboratory confirmation was impractical due to the isolation and poverty of the affected community and unnecessary due to the specific nature of the clinical signs. Respondents reported not having encountered the disease previously, and it would appear that a naïve local population developed within an endemically affected region because of a trend to avoid purchasing animals from outside the village. Local grazing practices appear to have had a role in both the spread and control of the outbreak. Goats are an important form of savings and cash income to people in the locality, and the outbreak may result in considerable financial hardship for affected goat keepers. We provide a detailed description of the clinical disease and the spread of the outbreak in the locality. Awareness of the disease with reference to farming practices will provide opportunities for future disease control to enhance animal welfare and rural prosperity.


Assuntos
Bem-Estar do Animal , Chordopoxvirinae/isolamento & purificação , Surtos de Doenças/veterinária , Doenças das Cabras/epidemiologia , Infecções por Poxviridae/veterinária , Animais , Feminino , Doenças das Cabras/transmissão , Cabras , Índia/epidemiologia , Masculino , Parques Recreativos , Infecções por Poxviridae/epidemiologia , População Rural
6.
Sci Rep ; 8(1): 5623, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618766

RESUMO

Crocodilepox virus is a large dsDNA virus belonging to the genus Crocodylidpoxvirus, which infects a wide range of host species in the order Crocodylia worldwide. Here, we present genome sequences for a novel saltwater crocodilepox virus, with two subtypes (SwCRV-1 and -2), isolated from the Australian saltwater crocodile. Affected belly skins of juvenile saltwater crocodiles were used to sequence complete viral genomes, and perform electron microscopic analysis that visualized immature and mature virions. Analysis of the SwCRV genomes showed a high degree of sequence similarity to CRV (84.53% and 83.70%, respectively), with the novel SwCRV-1 and -2 complete genome sequences missing 5 and 6 genes respectively when compared to CRV, but containing 45 and 44 predicted unique genes. Similar to CRV, SwCRV also lacks the genes involved in virulence and host range, however, considering the presence of numerous hypothetical and or unique genes in the SwCRV genomes, it is completely reasonable that the genes encoding these functions are present but not recognized. Phylogenetic analysis suggested a monophyletic relationship between SwCRV and CRV, however, SwCRV is quite distinct from other chordopoxvirus genomes. These are the first SwCRV complete genome sequences isolated from saltwater crocodile skin lesions.


Assuntos
Jacarés e Crocodilos/virologia , Chordopoxvirinae/genética , Genoma Viral , Genômica/métodos , Infecções por Poxviridae/genética , Dermatopatias/genética , Animais , Austrália , Chordopoxvirinae/classificação , Filogenia , Infecções por Poxviridae/virologia , Análise de Sequência de DNA , Dermatopatias/virologia , Virulência
7.
Sci Rep ; 7(1): 16472, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29184134

RESUMO

Poxviruses are large DNA viruses with varying zoonotic potential, and are recognised in a broad range of wildlife. Although poxviruses have been detected in kangaroos, their genetic relationships to poxviruses in other animals and humans is not well understood. Here, we present a novel genome sequence of a marsupial poxvirus, the Eastern grey kangaroopox virus (EKPV-NSW), isolated from a wild eastern grey kangaroo. In the present study, histopathologically confirmed epidermal pox lesions were used to recover the full-length viral genome and perform electron microscopic analysis, with both immature virions and intracellular mature virions detected. Subsequent analysis of the EKPV-NSW genome demonstrated the highest degree of sequence similarity with EKPV-SC strain (91.51%), followed by WKPV-WA (87.93%), and MOCV1 (44.05%). The novel EKPV-NSW complete genome encompasses most of the chordopoxviruses protein coding genes (138) that are required for genome replication and expression, with only three essential protein coding genes being absent. The novel EKPV-NSW is missing 28 predicted genes compared to the recently isolated EKPV-SC, and carries 21 additional unique genes, encoding unknown proteins. Phylogenetic and recombination analyses showed EKPV-NSW to be the distinct available candidate genome of chordopoxviruses.


Assuntos
Chordopoxvirinae/genética , Chordopoxvirinae/ultraestrutura , Genoma Viral , Genômica , Animais , Chordopoxvirinae/classificação , Biologia Computacional/métodos , Genômica/métodos , Macropodidae , Masculino , Anotação de Sequência Molecular , Filogenia , Infecções por Poxviridae/diagnóstico , Infecções por Poxviridae/veterinária
8.
J Virol ; 89(18): 9348-67, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26136578

RESUMO

UNLABELLED: Poxviruses are large DNA viruses of vertebrates and insects causing disease in many animal species, including reptiles, birds, and mammals. Although poxvirus-like particles were detected in diseased farmed koi carp, ayu, and Atlantic salmon, their genetic relationships to poxviruses were not established. Here, we provide the first genome sequence of a fish poxvirus, which was isolated from farmed Atlantic salmon. In the present study, we used quantitative PCR and immunohistochemistry to determine aspects of salmon gill poxvirus disease, which are described here. The gill was the main target organ where immature and mature poxvirus particles were detected. The particles were detected in detaching, apoptotic respiratory epithelial cells preceding clinical disease in the form of lethargy, respiratory distress, and mortality. In moribund salmon, blocking of gas exchange would likely be caused by the adherence of respiratory lamellae and epithelial proliferation obstructing respiratory surfaces. The virus was not found in healthy salmon or in control fish with gill disease without apoptotic cells, although transmission remains to be demonstrated. PCR of archival tissue confirmed virus infection in 14 cases with gill apoptosis in Norway starting from 1995. Phylogenomic analyses showed that the fish poxvirus is the deepest available branch of chordopoxviruses. The virus genome encompasses most key chordopoxvirus genes that are required for genome replication and expression, although the gene order is substantially different from that in other chordopoxviruses. Nevertheless, many highly conserved chordopoxvirus genes involved in viral membrane biogenesis or virus-host interactions are missing. Instead, the salmon poxvirus carries numerous genes encoding unknown proteins, many of which have low sequence complexity and contain simple repeats suggestive of intrinsic disorder or distinct protein structures. IMPORTANCE: Aquaculture is an increasingly important global source of high-quality food. To sustain the growth in aquaculture, disease control in fish farming is essential. Moreover, the spread of disease from farmed fish to wildlife is a concern. Serious poxviral diseases are emerging in aquaculture, but very little is known about the viruses and the diseases that they cause. There is a possibility that viruses with enhanced virulence may spread to new species, as has occurred with the myxoma poxvirus in rabbits. Provision of the first fish poxvirus genome sequence and specific diagnostics for the salmon gill poxvirus in Atlantic salmon may help curb this disease and provide comparative knowledge. Furthermore, because salmon gill poxvirus represents the deepest branch of chordopoxvirus so far discovered, the genome analysis provided substantial insight into the evolution of different functional modules in this important group of viruses.


Assuntos
Carpas/virologia , Chordopoxvirinae/genética , Doenças dos Peixes/virologia , Brânquias/virologia , Filogenia , Infecções por Poxviridae/genética , Salmo salar/virologia , Animais , Chordopoxvirinae/metabolismo , Doenças dos Peixes/genética , Doenças dos Peixes/metabolismo , Brânquias/metabolismo , Infecções por Poxviridae/metabolismo , Coelhos
9.
Viruses ; 7(4): 2126-46, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25912716

RESUMO

To investigate gene loss in poxviruses belonging to the Chordopoxvirinae subfamily, we assessed the gene content of representative members of the subfamily, and determined whether individual genes present in each genome were intact, truncated, or fragmented. When nonintact genes were identified, the early stop mutations (ESMs) leading to gene truncation or fragmentation were analyzed. Of all the ESMs present in these poxvirus genomes, over 65% co-localized with microsatellites-simple sequence nucleotide repeats. On average, microsatellites comprise 24% of the nucleotide sequence of these poxvirus genomes. These simple repeats have been shown to exhibit high rates of variation, and represent a target for poxvirus protein variation, gene truncation, and reductive evolution.


Assuntos
Chordopoxvirinae/genética , Variação Genética , Genoma Viral , Instabilidade Genômica , Repetições de Microssatélites , Códon sem Sentido , Biologia Computacional , Evolução Molecular , Deleção de Genes
10.
Biol Direct ; 9(1): 22, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25374149

RESUMO

UNLABELLED: Through the course of their evolution, viruses with large genomes have acquired numerous host genes, most of which perform function in virus reproduction in a manner that is related to their original activities in the cells, but some are exapted for new roles. Here we report the unexpected finding that protein F12, which is conserved among the chordopoxviruses and is implicated in the morphogenesis of enveloped intracellular virions, is a derived DNA polymerase, possibly of bacteriophage origin, in which the polymerase domain and probably the exonuclease domain have been inactivated. Thus, F12 appears to present a rare example of a drastic, exaptive functional change in virus evolution. REVIEWERS: This article was reviewed by Frank Eisenhaber and Juergen Brosius.


Assuntos
Chordopoxvirinae/genética , DNA Polimerase Dirigida por DNA/fisiologia , Proteínas Virais/fisiologia , Sequência de Aminoácidos , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/genética , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/genética , Vírion/metabolismo
11.
PLoS One ; 9(7): e96439, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24983354

RESUMO

Squirrelpox virus (SQPV) shows little evidence for morbidity or mortality in North American grey squirrels (Sciurus carolinensis), in which the virus is endemic. However, more recently the virus has emerged to cause epidemics with high mortality in Eurasian red squirrels (S. vulgaris) in Great Britain, which are now threatened. Here we report the genome sequence of SQPV. Comparison with other Poxviridae revealed a core set of poxvirus genes, the phylogeny of which showed SQPV to be in a new Chordopoxvirus subfamily between the Molluscipoxviruses and Parapoxviruses. A number of SQPV genes were related to virulence, including three major histocomaptibility class I homologs, and one CD47 homolog. In addition, a novel potential virulence factor showing homology to mammalian oligoadenylate synthetase (OAS) was identified. This family of proteins normally causes activation of an endoribonuclease (RNaseL) within infected cells. The putative function of this novel SQPV protein was predicted in silico.


Assuntos
Doenças dos Animais/genética , Chordopoxvirinae , Infecções por Poxviridae/genética , Sciuridae/virologia , Proteínas Virais/genética , Fatores de Virulência/genética , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais , Chordopoxvirinae/genética , Chordopoxvirinae/patogenicidade , Infecções por Poxviridae/epidemiologia , Homologia de Sequência de Aminoácidos , Reino Unido/epidemiologia
12.
PLoS One ; 9(2): e89521, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586845

RESUMO

Red squirrels (Sciurus vulgaris) declined in Great Britain and Ireland during the last century, due to habitat loss and the introduction of grey squirrels (Sciurus carolinensis), which competitively exclude the red squirrel and act as a reservoir for squirrelpox virus (SQPV). The disease is generally fatal to red squirrels and their ecological replacement by grey squirrels is up to 25 times faster where the virus is present. We aimed to determine: (1) the seropositivity and prevalence of SQPV DNA in the invasive and native species at a regional scale; (2) possible SQPV transmission routes; and, (3) virus degradation rates under differing environmental conditions. Grey (n = 208) and red (n = 40) squirrel blood and tissues were sampled. Enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qPCR) techniques established seropositivity and viral DNA presence, respectively. Overall 8% of squirrels sampled (both species combined) had evidence of SQPV DNA in their tissues and 22% were in possession of antibodies. SQPV prevalence in sampled red squirrels was 2.5%. Viral loads were typically low in grey squirrels by comparison to red squirrels. There was a trend for a greater number of positive samples in spring and summer than in winter. Possible transmission routes were identified through the presence of viral DNA in faeces (red squirrels only), urine and ectoparasites (both species). Virus degradation analyses suggested that, after 30 days of exposure to six combinations of environments, there were more intact virus particles in scabs kept in warm (25 °C) and dry conditions than in cooler (5 and 15 °C) or wet conditions. We conclude that SQPV is present at low prevalence in invasive grey squirrel populations with a lower prevalence in native red squirrels. Virus transmission could occur through urine especially during warm dry summer conditions but, more notably, via ectoparasites, which are shared by both species.


Assuntos
Chordopoxvirinae/genética , Infecções por Poxviridae/veterinária , Sciuridae/virologia , Animais , Anticorpos Antivirais/sangue , Chordopoxvirinae/imunologia , DNA Viral/genética , Reservatórios de Doenças/estatística & dados numéricos , Meio Ambiente , Fezes/virologia , Espécies Introduzidas , Viabilidade Microbiana , Irlanda do Norte/epidemiologia , Infecções por Poxviridae/sangue , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/transmissão , Prevalência , Estudos Soroepidemiológicos , Carga Viral
14.
J Gen Virol ; 92(Pt 11): 2596-2607, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21752962

RESUMO

Ankyrin-repeat (ANK) protein-interaction domains are common in cellular proteins but are relatively rare in viruses. Chordopoxviruses, however, encode a large number of ANK domain-containing ORFs of largely unknown function. Recently, a second protein-interaction domain, an F-box-like motif, was identified in several poxvirus ANK proteins. Cellular F-box proteins recruit substrates to the ubiquitination machinery of the cell, a putative function for ANK/poxviral F-box proteins. Using publicly available genome sequence data we examined all 328 predicted ANK proteins encoded by 27 chordopoxviruses that represented the eight vertebrate poxvirus genera whose members encode ANK proteins. Within these we identified 15 putative ANK protein orthologue groups within orthopoxviruses, five within parapoxviruses, 23 within avipoxviruses and seven across members of the genera Leporipoxvirus, Capripoxvirus, Yatapoxvirus, Suipoxvirus and Cervidpoxvirus. Sequence comparisons showed that members of each of these four clusters of orthologues were not closely related to members of any of the other clusters. Of these ORFs, 67% encoded a C-terminal poxviral F-box-like motif, whose absence could largely be attributed to fragmentation of ORFs. Our findings suggest that the large family of poxvirus ANK proteins arose by extensive gene duplication and divergence that occurred independently in four major genus-based groups after the groups diverged from each other. It seems likely that the ancestor ANK proteins of poxviruses contained both the N-terminal ANK repeats and a C-terminal F-box-like domain, with the latter domain subsequently being lost in a small subset of these proteins.


Assuntos
Chordopoxvirinae/classificação , Chordopoxvirinae/genética , Filogenia , Polimorfismo Genético , Proteínas Virais/genética , Repetição de Anquirina , Análise por Conglomerados , Biologia Computacional/métodos
15.
J Clin Microbiol ; 48(1): 268-76, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19906902

RESUMO

Chordopoxviruses of the subfamily Chordopoxvirinae, family Poxviridae, infect vertebrates and consist of at least eight genera with broad host ranges. For most chordopoxviruses, the number of viral genes and their relative order are highly conserved in the central region. The GC content of chordopoxvirus genomes, however, evolved into two distinct types: those with genome GC content of more than 60% and those with a content of less than 40% GC. Two standard PCR assays were developed to identify chordopoxviruses based on whether the target virus has a low or high GC content. In design of the assays, the genus Avipoxvirus, which encodes major rearrangements of gene clusters, was excluded. These pan-pox assays amplify DNA from more than 150 different isolates and strains, including from primary clinical materials, from all seven targeted genera of chordopoxviruses and four unclassified new poxvirus species. The pan-pox assays represent an important advance for the screening and diagnosis of human and animal poxvirus infections, and the technology used is accessible to many laboratories worldwide.


Assuntos
Chordopoxvirinae/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Poxviridae/diagnóstico , Infecções por Poxviridae/veterinária , Virologia/métodos , Animais , Composição de Bases , Sequência de Bases , Chordopoxvirinae/genética , DNA Viral/química , DNA Viral/genética , Humanos , Dados de Sequência Molecular , Filogenia , Infecções por Poxviridae/virologia , Alinhamento de Sequência , Vertebrados
16.
J Virol ; 83(24): 12822-32, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19812151

RESUMO

The original annotation of the vaccinia virus (VACV) genome was limited to open reading frames (ORFs) of at least 65 amino acids. Here, we characterized a 35-amino-acid ORF (O3L) located between ORFs O2L and I1L. ORFs similar in length to O3L were found at the same genetic locus in all vertebrate poxviruses. Although amino acid identities were low, the presence of a characteristic N-terminal hydrophobic domain strongly suggested that the other poxvirus genes were orthologs. Further studies demonstrated that the O3 protein was expressed at late times after infection and incorporated into the membrane of the mature virion. An O3L deletion mutant was barely viable, producing tiny plaques and a 3-log reduction in infectious progeny. A mutant VACV with a regulated O3L gene had a similar phenotype in the absence of inducer. There was no apparent defect in virus morphogenesis, though O3-deficient virus had low infectivity. The impairment was shown to be at the stage of virus entry, as cores were not detected in the cytoplasm after virus adsorption. Furthermore, O3-deficient virus did not induce fusion of infected cells when triggered by low pH. These characteristics are hallmarks of a group of proteins that form the entry/fusion complex (EFC). Affinity purification experiments demonstrated an association of O3 with EFC proteins. In addition, the assembly or stability of the EFC was impaired when expression of O3 was repressed. Thus, O3 is the newest recognized component of the EFC and the smallest VACV protein shown to have a function.


Assuntos
Vírus Vaccinia/química , Proteínas Virais/fisiologia , Sequência de Aminoácidos , Chordopoxvirinae/química , Citoplasma/química , Fusão de Membrana , Dados de Sequência Molecular , Fases de Leitura Aberta , Vírus Vaccinia/fisiologia , Proteínas Virais/química , Vírion/química , Vírion/fisiologia , Replicação Viral
17.
Dis Aquat Organ ; 85(3): 225-37, 2009 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-19750811

RESUMO

The presence of tattoo skin disease (TSD) was examined in 1392 free-ranging and dead odontocetes comprising 17 species from the Americas, Europe, South Africa, New Zealand and Greenland. We investigated whether TSD prevalence varied with sex, age and health status. TSD was encountered in cetaceans from the Pacific and Atlantic Oceans as well as in those from the North, Mediterranean and Tasman Seas. No clear patterns related to geography and host phylogeny were detected, except that prevalence of TSD in juveniles and, in 2 species (dusky dolphin Lagenorhynchus obscurus and Burmeister's porpoise Phocoena spinipinnis), in adults was remarkably high in samples from Peru. Environmental factors and virus properties may be responsible for this finding. Sex did not significantly influence TSD prevalence except in the case of Peruvian P. spinipinnis. Generally, there was a pattern of TSD increase in juveniles compared to calves, attributed to the loss of maternal immunity. Also, in most samples, juveniles seemed to have a higher probability of suffering TSD than adults, presumably because more adults had acquired active immunity following infection. This holo-endemic pattern was inverted in poor health short-beaked common dolphins Delphinus delphis and harbour porpoises Phocoena phocoena from the British Isles, and in Chilean dolphins Cephalorhynchus eutropia from Patagonia, where adults showed a higher TSD prevalence than juveniles. Very large tattoos were seen in some adult odontocetes from the SE Pacific, NE Atlantic and Portugal's Sado Estuary, which suggest impaired immune response. The epidemiological pattern of TSD may be an indicator of cetacean population health.


Assuntos
Cetáceos/fisiologia , Infecções por Poxviridae/epidemiologia , Dermatopatias/epidemiologia , Distribuição por Idade , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais , Chordopoxvirinae/fisiologia , Feminino , Masculino , Fatores Sexuais , Dermatopatias/virologia
18.
Epidemiol Infect ; 137(2): 257-65, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18606024

RESUMO

Squirrelpox virus (SQPV) causes a fatal disease in free-living red squirrels (Sciurus vulgaris) which has contributed to their decline in the United Kingdom. Given the difficulty of carrying out and funding experimental investigations on free-living wild mammals, data collected from closely monitored natural outbreaks of disease is crucial to our understanding of disease epidemiology. A conservation programme was initiated in the 1990s to bolster the population of red squirrels in the coniferous woodland of Thetford Chase, East Anglia. In 1996, 24 red squirrels were reintroduced to Thetford from Northumberland and Cumbria, while in 1999 a captive breeding and release programme commenced, but in both years the success of the projects was hampered by an outbreak of SQPV disease in which seven and four red squirrels died respectively. Valuable information on the host-pathogen dynamics of SQPV disease was gathered by telemetric and mark-recapture monitoring of the red squirrels. SQPV disease characteristics were comparable to other virulent poxviral infections: the incubation period was <15 days; the course of the disease an average of 10 days and younger animals were significantly more susceptible to disease. SQPV disease places the conservation of the red squirrel in jeopardy in the United Kingdom unless practical disease control methods can be identified.


Assuntos
Chordopoxvirinae/isolamento & purificação , Surtos de Doenças/veterinária , Infecções por Poxviridae/veterinária , Doenças dos Roedores/epidemiologia , Sciuridae/virologia , Fatores Etários , Animais , Feminino , Período de Incubação de Doenças Infecciosas , Masculino , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/patologia , Infecções por Poxviridae/virologia , Doenças dos Roedores/patologia , Doenças dos Roedores/virologia , Fatores de Tempo , Reino Unido
20.
Mol Ther ; 16(9): 1637-42, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18628758

RESUMO

JX-594 is a targeted oncolytic poxvirus that is designed to eradicate cancer cells having cell-cycle defects, through replication, cell lysis, and spread within tumors; oncolysis-induced tumor vascular shutdown and immunostimulation are augmented by granulocyte monocyte-colony-stimulating factor (GM-CSF) transgene expression. We have previously shown, in animal models of hepatocellular carcinoma (HCC), that JX-594 is a promising anticancer agent. We tested JX-594 in three patients with advanced refractory hepatitis B virus (HBV)-associated HCC through intratumoral administration. JX-594 treatment was well-tolerated and resulted in antitumoral efficacy in all three patients, despite the presence of high levels of neutralizing antibodies. JX-594 replication, its release into the circulation, distant tumor targeting were demonstrated. JX-594 administration resulted in the induction of antivascular cytokines, and was associated with tumor vascular shutdown. We also showed, for the first time, that oncolytic virotherapy can suppress underlying HBV replication in HCC patients, and that tumor tissue could be the primary source of acute HBV replication and acute post-treatment HBV release. JX-594 treatment in HBV-associated HCC warrants further clinical testing; a Phase II trial is underway.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/terapia , Chordopoxvirinae/genética , Hepatite B/terapia , Terapia Viral Oncolítica , Replicação Viral , Idoso , Carcinoma Hepatocelular/secundário , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , DNA Viral/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Hepatite B/imunologia , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/metabolismo , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/metabolismo
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