| porcine teschoviruses comprise at least eleven distinct serotypes: molecular and evolutionary aspects. | nucleotide sequencing and phylogenetic analysis of 10 recognized prototype strains of the porcine enterovirus (pev) cytopathic effect (cpe) group i reveals a close relationship of the viral genomes to the previously sequenced strain f65, supporting the concept of a reclassification of this virus group into a new picornavirus genus. also, nucleotide sequences of the polyprotein-encoding genome region or the p1 region of 28 historic strains and recent field isolates were determined. the data sugge ... | 2001 | 11160660 |
| phylogenetic analysis of ljungan virus and a-2 plaque virus, new members of the picornaviridae. | in addition to the viruses belonging to the nine proposed genera of the picornaviridae, enterovirus, rhinovirus, cardiovirus, aphtovirus, hepatovirus, parechovirus, kobuvirus, erbovirus and teschovirus, two new members of this family have recently been discovered. three strains of ljungan virus (lv) were isolated from bank voles (clethrionomys glareolus) and a-2 plaque virus (a-2) was isolated from human sera. to study the genetic relationship between these recently discovered viruses and the me ... | 2002 | 11955639 |
| unique characteristics of a picornavirus internal ribosome entry site from the porcine teschovirus-1 talfan. | the teschoviruses constitute a recently defined picornavirus genus. most of the genome sequence of the porcine teschovirus-1 (ptv) talfan and several other strains is known. we now demonstrate that initiation of protein synthesis occurs at nucleotide (nt) 412 on the ptv talfan rna and that nt 1 to 405 contains an internal ribosome entry site (ires) that functions efficiently in vitro and within mammalian cells. in comparison with other picornavirus ires elements, the ptv ires is relatively short ... | 2002 | 12388732 |
| detection of porcine teschovirus and enterovirus type ii by reverse transcription-polymerase chain reaction. | porcine enteroviruses (pevs) have been recognized as the causative agents of various clinical manifestations such as fertility disorders, neurological defects, and dermal lesions in pigs. currently, the diagnosis of pev infection is carried out by virus isolation, which although useful, is labor- and time-intensive. the present investigation describes the development of a reverse transcription-polymerase chain reaction (rt-pcr) assay for the rapid and sensitive detection of pevs of cytopathic ef ... | 2002 | 12423029 |
| genomic evidence that simian virus 2 and six other simian picornaviruses represent a new genus in picornaviridae. | analysis of the vp1 capsid protein coding region of simian virus (sv) 2, sv16, sv18, sv42, sv44, sv45, and sv49 demonstrates that they are clearly distinct from members of the enterovirus genus and from members of other existing picornavirus genera. to further characterize this group of viruses and to clarify their classification within the picornaviridae, we have determined the complete genomic sequence of sv2 (8126 nucleotides). the genome was typical of members of picornaviridae, encoding a s ... | 2003 | 14517081 |
| teschoviruses as indicators of porcine fecal contamination of surface water. | teschoviruses specifically infect pigs and are shed in pig feces. hence, their presence in water should indicate contamination with pig fecal residues. to assess this hypothesis, we have developed a real-time reverse transcriptase pcr (rt-pcr) method that allows the quantitative detection of pig teschovirus (ptv) rna. the method is able to detect 92 fg of ptv rna per ml of sample. using this method, we have detected the presence of ptv rna in water and fecal samples from all pig farms examined ( ... | 2003 | 14532098 |
| functional and structural similarities between the internal ribosome entry sites of hepatitis c virus and porcine teschovirus, a picornavirus. | initiation of protein synthesis on picornavirus rna requires an internal ribosome entry site (ires). typically, picornavirus ires elements contain about 450 nucleotides (nt) and use most of the cellular translation initiation factors. however, it is now shown that just 280 nt of the porcine teschovirus type 1 talfan (ptv-1) 5' untranslated region direct the efficient internal initiation of translation in vitro and within cells. in toeprinting assays, assembly of 48s preinitiation complexes from ... | 2004 | 15078929 |
| phylogeny of the picornaviridae and differential evolutionary divergence of picornavirus proteins. | a rooted phylogenetic analysis of the viral family picornaviridae identified several major clusters within this viral family. the genus parechovirus, including ljungan virus, was found to be basal to the family. within the family, there were two major subgroups: (1) a cluster including viruses assigned to the genera enterovirus and rhinovirus; and (2) a cluster including teschovirus, cardiovirus, erbovirus, aphthovirus, and probably kobuvirus. within the former cluster, the genera enterovirus an ... | 2004 | 15157632 |
| enterovirus encephalomyelitis in pigs in japan caused by porcine teschovirus. | | 2004 | 15478502 |
| linkage map of protein-protein interactions of porcine teschovirus. | a yeast two-hybrid study was conducted to catalogue the protein-protein interactions of the porcine teschovirus non-structural proteins. five homodimer, three reciprocal heterodimer and four unidirectional heterodimer interactions were observed. while several interactions are similar to those described in previous studies using enteroviruses, such as homo- and heterodimeric interactions of the 2b, 3cd and 3d proteins, several were not found previously. among these is the binding of the leader pr ... | 2005 | 16186230 |
| functional analyses of rna structures shared between the internal ribosome entry sites of hepatitis c virus and the picornavirus porcine teschovirus 1 talfan. | the internal ribosome entry site (ires) of porcine teschovirus 1 (ptv-1), a member of the picornaviridae family, is quite distinct from other well-characterized picornavirus ires elements, but it displays functional similarities to the ires from hepatitis c virus (hcv), a member of the flaviviridae family. in particular, a dominant negative mutant form of eif4a does not inhibit the activity of the ptv-1 ires. furthermore, there is a high level (ca. 50%) of identity between the ptv-1 and hcv ires ... | 2006 | 16415004 |
| hepatitis c virus-related internal ribosome entry sites are found in multiple genera of the family picornaviridae. | the internal ribosome entry site (ires) elements from porcine enterovirus 8 and simian virus 2, two members of a proposed new genus within the family picornaviridae, were characterized. these ires elements, in common with the porcine teschovirus 1 ires, were found to be related functionally and structurally to the ires element from hepatitis c virus, a member of the family flaviviridae. partial secondary structure predictions were derived and functional assays demonstrated that these ires elemen ... | 2006 | 16528042 |
| validation of rt-pcr assays for molecular characterization of porcine teschoviruses and enteroviruses. | porcine enteroviruses (pevs) and teschoviruses (ptvs) are described as causative agents of neurological disorders, fertility disorders and dermal lesions of swine. difficulties in the serological detection of these viruses may lead to a significant underestimation of infections with clinical symptoms. with the recent availability of genome sequence data for all the serotypes, molecular diagnosis is a possibility. the present study describes a new approach to molecular 'serotyping' of ptvs and pe ... | 2006 | 16907956 |
| recombination patterns in aphthoviruses mirror those found in other picornaviruses. | foot-and-mouth disease virus (fmdv) is thought to evolve largely through genetic drift driven by the inherently error-prone nature of its rna polymerase. there is, however, increasing evidence that recombination is an important mechanism in the evolution of these and other related picornoviruses. here, we use an extensive set of recombination detection methods to identify 86 unique potential recombination events among 125 publicly available fmdv complete genome sequences. the large number of eve ... | 2006 | 16971423 |
| antigenic properties of porcine teschovirus 1 (ptv-1) talfan strain and molecular strategy for serotyping of ptvs. | for reliable diagnosis of porcine teschovirus (ptv) infection we created an rt-pcr-based molecular strategy for serotyping that encompassed the dominant neutralizing antigenic site of ptv, followed by phylogenetic analyses of amplicons. we identified neutralizing antigenic sites of ptv-1 talfan strain through epitope mapping of neutralizing monoclonal antibodies (mabs), using synthetic peptides spanning the capsid proteins. all 11 mabs obtained recognized peptides in the ef loop ("puff") of vp2 ... | 2007 | 17265104 |
| molecular analysis of duck hepatitis virus type 1. | the genome sequence of a duck hepatitis virus type 1 (dhv-1) strain was determined. comparative sequence analysis showed that the genome possesses a typical picornarivus organization and also exhibits several unique features, such as the similarity of internal ribosome entry site to that of porcine teschovirus 1 and hepatitis c virus, the presence of a longest 3' untranslated region and a shorter leader protein in the picornaviridae, the absence of a predicted maturation cleavage of vp0, the ass ... | 2007 | 17300822 |
| a distinct group of hepacivirus/pestivirus-like internal ribosomal entry sites in members of diverse picornavirus genera: evidence for modular exchange of functional noncoding rna elements by recombination. | the 5' untranslated regions (utrs) of the rna genomes of flaviviridae of the hepacivirus and pestivirus genera contain internal ribosomal entry sites (iress) that are unrelated to the two principal classes of iress of picornaviridae. the mechanism of translation initiation on hepacivirus/pestivirus (hp) iress, which involves factor-independent binding to ribosomal 40s subunits, also differs fundamentally from initiation on these picornavirus iress. ribosomal binding to hp iress requires conserve ... | 2007 | 17392358 |
| isolation and molecular characterization of a porcine teschovirus 1 isolate from china. | porcine teschovirus 1 (ptv-1) (swine/ch/imh/03) was isolated from piglets in a farm in inner mongolia province, p.r. china. it was confirmed by electron microscopy, rt-pcr, and sequencing. comparison of the sequences of the amino acid and nucleotides and phylogenetic analysis of the polyprotein showed that ptv swine/ch/imh/03 strain is ptv-1. the isolated virus has closest relationship with talfan strain, they shared 98.9% and 99.5% homology of amino acids and nucleotides, respectively, in the o ... | 2007 | 17432938 |
| immunohistochemical detection of porcine teschovirus antigen in the formalin-fixed paraffin-embedded specimens from pigs experimentally infected with porcine teschovirus. | porcine teschovirus (ptv) antigens were detected by a streptavidin-biotin complex method in formalin-fixed paraffin-embedded tissues of 3-week-old pigs that had been inoculated intravenously with ptv talfan strain. ptv antigens were detected in cytoplasm of nerve cells, glial cells and endothelial cells in the cerebellar nuclei, the grey matter of the midbrain, pons and medulla oblongata and the ventral horn of the spinal cord and of ganglion cells in the spinal ganglion corresponding to those l ... | 2007 | 18045341 |
| the picornavirus avian encephalomyelitis virus possesses a hepatitis c virus-like internal ribosome entry site element. | avian encephalomyelitis virus (aev) is a picornavirus that causes disease in poultry worldwide, and flocks must be vaccinated for protection. aev is currently classified within the hepatovirus genus, since its proteins are most closely related to those of hepatitis a virus (hav). we now provide evidence that the 494-nucleotide-long 5' untranslated region of the aev genome contains an internal ribosome entry site (ires) element that functions efficiently in vitro and in mammalian cells. unlike th ... | 2008 | 18077729 |
| expression of heterologous genes in oncolytic adenoviruses using picornaviral 2a sequences that trigger ribosome skipping. | insertion of picornaviral 2a sequences into mrnas causes ribosomes to skip formation of a peptide bond at the junction of the 2a and downstream sequences, leading to the production of two proteins from a single open reading frame. adenoviral protein ix is a minor capsid protein that has been used to display foreign peptides on the surface of the capsid. we have used 2a sequences from the foot-and-mouth disease virus (fmdv) and porcine teschovirus 1 (ptv-1) to express protein ix (pix) and green f ... | 2008 | 18198369 |
| retroviral transfer of a dominant tcr prevents surface expression of a large proportion of the endogenous tcr repertoire in human t cells. | the latent membrane protein-2 (lmp2) of epstein-barr virus is a potential target for t-cell receptor (tcr) gene therapy of hodgkin lymphoma and nasopharyngeal carcinoma. here, we modified a human leukocyte antigen-a2-restricted, lmp2-specific tcr to achieve efficient expression following retroviral tcr gene transfer. the unmodified tcr was poorly expressed in primary human t cells, suggesting that it competed inefficiently with endogenous tcr chains for cell surface expression. in order to impro ... | 2008 | 18305579 |
| immunohistochemical distribution of viral antigens in pigs naturally infected with porcine teschovirus. | a distribution of porcine teschovirus (ptv) antigens in pigs naturally infected with ptv is presented using the method of immunohistochemical examination. in the nervous system, ptv antigens were found in the cytoplasm of neuronal cells and glial cells distributed in the spinal ventral horn and brain stem, and also in the cytoplasm of ganglion cells in the spinal ganglion. no antigens were seen in the cerebral hemisphere. in the nervous system, the distribution of ptv antigens was consistent wit ... | 2008 | 18388434 |
| a piglet with concurrent polioencephalomyelitis due to porcine teschovirus and postweaning multisystemic wasting syndrome. | a piglet developed respiratory distress followed by difficulty in standing and unsteady gait. the lesions were characterized by polioencephalomyelitis with the predominant distribution in the brain stem, as well as lymphocyte depletion and histiocyte infiltration with cytoplasmic inclusion bodies in the lymphoid tissues throughout the body and interstitial pneumonia. porcine teschovirus (ptv) antigens were found in the former lesions and porcine circovirus 2 (pcv2) in the latter two lesions. ptv ... | 2008 | 18525174 |
| monocistronic mrnas containing defective hepatitis c virus-like picornavirus internal ribosome entry site elements in their 5' untranslated regions are efficiently translated in cells by a cap-dependent mechanism. | the initiation of protein synthesis on mrnas within eukaryotic cells is achieved either by a 5' cap-dependent mechanism or through internal initiation directed by an internal ribosome entry site (ires). picornavirus ires elements, located in the 5' untranslated region (5'utr), contain extensive secondary structure and multiple upstream aug codons. these features can be expected to inhibit cap-dependent initiation of translation. however, we have now shown that certain mutant hepatitis c virus-li ... | 2008 | 18567818 |
| divergent picornavirus ires elements. | internal ribosome entry site (ires) elements were first identified about 20 years ago within the 5' untranslated region of picornavirus rnas. they direct a cap-independent mechanism of translation initiation on the viral rna. within the picornavirus family it is now known that there are four classes of ires element which vary in size (450-270 nt), they also have different, complex, secondary structures and distinct requirements for cellular proteins to allow them to function. this review describ ... | 2009 | 18675861 |
| polycistronic lentiviral vector for "hit and run" reprogramming of adult skin fibroblasts to induced pluripotent stem cells. | we report the derivation of induced pluripotent stem (ips) cells from adult skin fibroblasts using a single, polycistronic lentiviral vector encoding the reprogramming factors oct4, sox2, and klf4. porcine teschovirus-1 2a sequences that trigger ribosome skipping were inserted between human cdnas for these factors, and the polycistron was subcloned downstream of the elongation factor 1 alpha promoter in a self-inactivating (sin) lentiviral vector containing a loxp site in the truncated 3' long t ... | 2009 | 19415770 |
| the complete genome of klassevirus - a novel picornavirus in pediatric stool. | diarrhea kills 2 million children worldwide each year, yet an etiological agent is not found in approximately 30-50% of cases. picornaviral genera such as enterovirus, kobuvirus, cosavirus, parechovirus, hepatovirus, teschovirus, and cardiovirus have all been found in human and animal diarrhea. modern technologies, especially deep sequencing, allow rapid, high-throughput screening of clinical samples such as stool for new infectious agents associated with human disease. | 2009 | 19538752 |
| pathological changes in pigs experimentally infected with porcine teschovirus. | nonsuppurative encephalomyelitis with neurological signs expressed as flaccid paralysis of the hindlimbs was experimentally induced in three-week-old piglets by a single intravenous injection of the toyama 2002 strain of porcine teschovirus (ptv) isolated from field pigs in japan. lesions characterized by perivascular cuffing of mononuclear cells, focal gliosis, neuronal necrosis and neuronophagia were observed, mainly in the ventral horn of the spinal cord. nonsuppurative ganglionitis of the sp ... | 2009 | 19570545 |
| conserved functional domains and a novel tertiary interaction near the pseudoknot drive translational activity of hepatitis c virus and hepatitis c virus-like internal ribosome entry sites. | the translational activity of the hepatitis c virus (hcv) internal ribosome entry site (ires) and other hcv-like ires rnas depends on structured rna elements in domains ii and iii, which serve to recruit the ribosomal 40s subunit, eukaryotic initiation factor (eif) 3 and the ternary eif2/met-trna(i)(met)/gtp complex and subsequently domain ii assists subunit joining. porcine teschovirus-1 talfan (ptv-1) is a member of the picornaviridae family, with a predicted hcv-like secondary structure, but ... | 2009 | 19596815 |
| development and laboratory evaluation of a lateral flow device for the detection of swine vesicular disease virus in clinical samples. | a lateral flow device (lfd) for the detection of swine vesicular disease (svd) virus (svdv) and differential diagnosis from foot-and-mouth disease (fmd) was developed using a monoclonal antibody (mab c70). the performance of the lfd was evaluated in the laboratory on suspensions of vesicular epithelia and cell culture passage derived supernatants of svdv and porcine teschovirus (enterovirus; pev). the collection of test samples included 157 which were positive for svdv (84 vesicular epithelial s ... | 2010 | 19819260 |
| influence of the hepatitis c virus 3'-untranslated region on ires-dependent and cap-dependent translation initiation. | translation of hepatitis c virus (hcv) genomic rna is directed by an internal ribosome entry site (ires) in the 5'-untranslated region (5'-utr), and the hcv 3'-utr enhances ires activity. since the hcv 3'-utr has a unique structure among 3'-utrs, we checked possible communication between the 5'- and the 3'-utr of hcv during translation using chimeric reporter rnas. we show that translation directed by the hcv ires and by the hcv-like ires of porcine teschovirus (ptv) which belongs to a quite dis ... | 2010 | 20079737 |
| isolation and characterization of the first chinese strain of porcine teschovirus-8. | investigations were carried out to identify the causal agent of acute diarrhea, respiratory distress, and death of pigs on a swine farm in jilin province, northern china. only porcine teschovirus (ptv, designated as ptv-8 jilin/2003) was isolated from samples of organs. the presence of ptv was confirmed by the production of a specific cytopathic effect on susceptible cells and by the results of the immunoperoxidase monolayer assay (ipma), polymerase chain reaction, and electron microscopy. other ... | 2010 | 20362007 |
| isolation of serotype 2 porcine teschovirus in china: evidence of natural recombination. | porcine teschovirus (ptv), the pathogen of porcine polioencephalomyelitis, is a member of the family picornaviridae. in this study, a new ptv strain (designated as jf613) was isolated from pigs in china. it was confirmed by the specific cpe on susceptible cells, rt-pcr and nucleotide sequencing. analysis of its amino acids sequence of complete polyprotein indicated that the isolate belongs to serotype 2. genetic recombination is a well-known phenomenon for picornavirus which has been demonstrate ... | 2010 | 20537819 |
| genotyping of porcine teschovirus from nervous tissue of pigs with and without polioencephalomyelitis in indiana. | porcine teschovirus (ptv) was isolated in cell culture and/or demonstrated by polymerase chain reaction in samples of brain and/or spinal cord in pigs in indiana during the 2002-2007 period. testing was initiated on pigs originating from populations exhibiting nervous clinical disease and/or pigs with microscopic lesions in central nervous tissues, indicating viral encephalitis and/or myelitis. virus was demonstrated in pigs with and without lesions as well as with and without nervous clinical d ... | 2010 | 20622231 |
| a survey of porcine picornaviruses and adenoviruses in fecal samples in spain. | in the course of an epidemiologic surveillance program for swine diseases carried out in spain, 206 cytopathic viruses were isolated from 600 porcine fecal samples between 2004 and 2005. the virus isolates were examined using reverse transcription polymerase chain reaction (rt-pcr) methods specific for different types of porcine picornaviruses, including members of the teschovirus, enterovirus, and sapelovirus genera, and pcr for porcine adenoviruses. of the 206 isolates, 97 (47%) were identifie ... | 2010 | 20807938 |
| molecular characterization and phylogenetic analysis of vp1 of porcine enteric picornaviruses isolates in italy. | porcine enterovirus (pev), porcine teschovirus and porcine sapelovirus, belonging to the family picornaviridae, are ubiquitous and mainly cause asymptomatic infections in pigs. in this study, a total of 40 italian porcine picornavirus isolates were characterized by sequencing the capsid vp1-encoding gene. this procedure turned out to be a useful diagnostic tool for the molecular identification of porcine enterovirus, teschovirus and sapelovirus strains and for the study of molecular epidemiology ... | 2010 | 21040508 |
| a multiplex rt-pcr for rapid and simultaneous detection of porcine teschovirus, classical swine fever virus, and porcine reproductive and respiratory syndrome virus in clinical specimens. | a multiplex rt-pcr (mrt-pcr) assay was developed and evaluated for its ability to detect multiple viral infections of swine simultaneously. one pair of primers was selected carefully for each of the following three rna viruses: porcine reproductive and respiratory syndrome virus (prrsv), classical swine fever virus (csfv), and porcine teschovirus (ptv). each target produced a specific amplicon with a size of 451bp (prrsv), 343bp (csfv), or 163bp (ptv). the sensitivity of the mrt-pcr using purifi ... | 2010 | 21192983 |
| porcine teschovirus polioencephalomyelitis in western canada. | beginning in 2002, a small number of pig farms in western canada began reporting 4-7-week-old pigs with bilateral hind-end paresis or paralysis. low numbers of pigs were affected, some died, most had to be euthanized, and those that survived had reduced weight gains and neurological deficits. necropsies revealed no gross lesions, but microscopic lesions consisted of a nonsuppurative polioencephalomyelitis, most severe in the brain stem and spinal cord. the lesions were most consistent with a vir ... | 2011 | 21398466 |
| high cleavage efficiency of a 2a peptide derived from porcine teschovirus-1 in human cell lines, zebrafish and mice. | when expression of more than one gene is required in cells, bicistronic or multicistronic expression vectors have been used. among various strategies employed to construct bicistronic or multicistronic vectors, an internal ribosomal entry site (ires) has been widely used. due to the large size and difference in expression levels between genes before and after ires, however, a new strategy was required to replace ires. a self-cleaving 2a peptide could be a good candidate to replace ires because o ... | 2011 | 21602908 |
| evaluation of a fluorogenic real-time reverse transcription-polymerase chain reaction method for the specific detection of all known serotypes of porcine teschoviruses. | performance of a real-time reverse-transcription polymerase chain reaction method for the rapid, simple and reliable detection of porcine teschovirus (ptv) was assessed. the method was based on the use of a set of oligonucleotides consisting of two specific primers and a fluorogenic taqman-mgb probe. reverse transcription and pcr reactions were performed sequentially in one step. as a result the whole procedure was simple and rapid, taking less than 3h for completion. the method reacted in a dos ... | 2011 | 21663764 |
| Duck Hepatitis A Virus Possesses a Distinct Type IV Internal Ribosome Entry Site Element of Picornavirus. | Sequence analysis of duck hepatitis virus type 1 (DHV-1) led to its classification as the only member of a new genus, Avihepatovirus, of the family Picornaviridae, and so was renamed duck hepatitis A virus (DHAV). The 5' untranslated region (5' UTR) plays an important role in translation initiation and RNA synthesis of the picornavirus. Here, we provide evidence that the 651-nucleotide (nt)-long 5' UTR of DHAV genome contains an internal ribosome entry site (IRES) element that functions efficien ... | 2012 | 22090106 |
| analyzing the genetic diversity of teschoviruses in spanish pig populations using complete vp1 sequences. | porcine teschoviruses (ptvs) have been previously shown to be the most abundant cytopathic viruses found in swine feces. in the present study, the diversity of ptvs was studied, using ptv isolates collected between 2004 and 2009 in a wide territory in spain. in order to characterize genetically the isolates, phylogeny reconstructions were made using maximum likelihood and bayesian inference methods, based on the 1d (vp1) gene, and including sequences available in public databases. the phylogenet ... | 2011 | 21983686 |
| development of a reverse transcription loop-mediated isothermal amplification assay for detection of porcine teschovirus. | loop-mediated isothermal ampliļ¬cation (lamp) is a sensitive method for dna ampliļ¬cation. in the present report, the development of a single-tube, one-step, real-time accelerated reverse transcription (rt)-lamp for the detection of porcine teschovirus (ptv) is described. six designed primers amplified target gene sequences successfully at constant temperature (65 °c) within 1 hr, and the amplification results could be visualized directly by the naked eye. the sensitivity of the lamp was 10 times ... | 2011 | 21908281 |