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Linfa Wang - One of the best experts on this subject based on the ideXlab platform.
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ictv virus taxonomy profile Paramyxoviridae
Journal of General Virology, 2019Co-Authors: Bert K Rima, Gael Kurath, Andrew J Easton, Paul A. Rota, Robert A Lamb, Anne Balkemabuschmann, William G Dundon, Paul Duprex, Ron A M Fouchier, Linfa WangAbstract:The family Paramyxoviridae consists of large enveloped RNA viruses infecting mammals, birds, reptiles and fish. Many paramyxoviruses are host-specific and several, such as measles virus, mumps virus, Nipah virus, Hendra virus and several parainfluenza viruses, are pathogenic for humans. The transmission of paramyxoviruses is horizontal, mainly through airborne routes; no vectors are known. This is a summary of the current International Committee on Taxonomy of Viruses (ICTV) Report on the family Paramyxoviridae. which is available at ictv.global/report/Paramyxoviridae.
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Problems of classification in the family Paramyxoviridae
Archives of Virology, 2018Co-Authors: Bert Rima, Gael Kurath, Robert A Lamb, Peter Collins, Andrew Easton, Ron Fouchier, Andrea Maisner, Paul Rota, Linfa WangAbstract:A number of unassigned viruses in the family Paramyxoviridae need to be classified either as a new genus or placed into one of the seven genera currently recognized in this family. Furthermore, numerous new paramyxoviruses continue to be discovered. However, attempts at classification have highlighted the difficulties that arise by applying historic criteria or criteria based on sequence alone to the classification of the viruses in this family. While the recent taxonomic change that elevated the previous subfamily Pneumovirinae into a separate family Pneumoviridae is readily justified on the basis of RNA dependent -RNA polymerase (RdRp or L protein) sequence motifs, using RdRp sequence comparisons for assignment to lower level taxa raises problems that would require an overhaul of the current criteria for assignment into genera in the family Paramyxoviridae . Arbitrary cut off points to delineate genera and species would have to be set if classification was based on the amino acid sequence of the RdRp alone or on pairwise analysis of sequence complementarity (PASC) of all open reading frames (ORFs). While these cut-offs cannot be made consistent with the current classification in this family, resorting to genus-level demarcation criteria with additional input from the biological context may afford a way forward. Such criteria would reflect the increasingly dynamic nature of virus taxonomy even if it would require a complete revision of the current classification.
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the complete genome sequence of j virus reveals a unique genome structure in the family Paramyxoviridae
Journal of Virology, 2005Co-Authors: Philippa J M Jack, Bryan T Eaton, David B Boyle, Linfa WangAbstract:J virus (J-V) was isolated from feral mice ( Mus musculus ) trapped in Queensland, Australia, during the early 1970s. Although studies undertaken at the time revealed that J-V was a new paramyxovirus, it remained unclassified beyond the family level. The complete genome sequence of J-V has now been determined, revealing a genome structure unique within the family Paramyxoviridae . At 18,954 nucleotides (nt), the J-V genome is the largest paramyxovirus genome sequenced to date, containing eight genes in the order 3′-N-P/V/C-M-F-SH-TM-G-L-5′. The two genes located between the fusion (F) and attachment (G) protein genes, which have been named the small hydrophobic (SH) protein gene and the transmembrane (TM) protein gene, encode putative proteins of 69 and 258 amino acids, respectively. The 4,401-nt J-V G gene, much larger than other paramyxovirus attachment protein genes sequenced to date, encodes a putative attachment protein of 709 amino acids and distally contains a second open reading frame (ORF) of 2,115 nt, referred to as ORF-X. Taken together, these novel features represent the most significant divergence to date from the common six-gene genome structure of Paramyxovirinae . Although genome analysis has confirmed that J-V can be classified as a member of the subfamily Paramyxovirinae , it cannot be assigned to any of the five existing genera within this subfamily. Interestingly, a recently isolated paramyxovirus appears to be closely related to J-V, and preliminary phylogenetic analyses based on putative matrix protein sequences indicate that these two viruses will likely represent a new genus within the subfamily Paramyxovirinae .
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tioman virus a novel paramyxovirus isolated from fruit bats in malaysia
Virology, 2001Co-Authors: Kaw Bing Chua, Linfa Wang, Meng Yu, Gary Crameri, David B Boyle, Terry G Wise, Alex D Hyatt, Bryan T EatonAbstract:Abstract A search for the natural host of Nipah virus has led to the isolation of a previously unknown member of the family Paramyxoviridae. Tioman virus (TiV) was isolated from the urine of fruit bats ( Pteropus hypomelanus ) found on the island of the same name off the eastern coast of peninsular Malaysia. An electron microscopic study of TiV-infected cells revealed spherical and pleomorphic-enveloped viral particles (100–500 nm in size) with a single fringe of embedded peplomers. Virus morphogenesis occurred at the plasma membrane of infected cells and morphological features of negative-stained ribonucleoprotein complexes were compatible with that of viruses in the family Paramyxoviridae. Serological studies revealed no cross-reactivity with antibodies against a number of known Paramyxoviridae members except for the newly described Menangle virus (MenV), isolated in Australia in 1997. Failure of PCR amplification using MenV-specific primers suggested that this new virus is related to but different from MenV. For molecular characterization of the virus, a cDNA subtraction strategy was employed to isolate virus-specific cDNA from virus-infected cells. Complete gene sequences for the nucleocapsid protein (N) and phosphoprotein (P/V) have been determined and recombinant N and V proteins produced in baculovirus. The recombinant N and V proteins reacted with porcine anti-MenV sera in Western blot, confirming the serological cross-reactivity observed during initial virus characterization. The lack of a C protein-coding region in the P/V gene, the creation of P mRNA by insertion of 2-G residues, and the results of phylogenetic analyses all indicated that TiV is a novel member of the genus Rubulavirus .
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the exceptionally large genome of hendra virus support for creation of a new genus within the family Paramyxoviridae
Journal of Virology, 2000Co-Authors: Linfa Wang, Meng Yu, Eric Hansson, Ian L Pritchard, Brian J Shiell, Wojtek P Michalski, Bryan T EatonAbstract:Although they manifest diverse biological properties, viruses in the families Filoviridae, Paramyxoviridae, Rhabdoviridae, and Bornaviridae all contain a nonsegmented negative-strand (NNS) RNA genome and share features of genome organization. These facts, together with similarities in domain structure and sequence of the viral polymerase proteins, suggest a close phylogenetic relationship. The four families are now grouped taxonomically in the order Mononegavirales, the first taxon above family level to be recognized in virus taxonomy (23, 25). The genome size of viruses in the order varies significantly, ranging from 8.9 kb in the Bornaviridae to 19.1 kb in the Filoviridae. Members of the Rhabdoviridae and Paramyxoviridae have intermediate genome sizes, 10.8 to 14.9 kb and 15.1 to 15.9 kb, respectively. Two interesting observations can be made from the comparison of genome sizes. First, there is no overlap of genome size between virus families. Second, genome size ranges differ significantly between the two families in which multiple genera have been defined, the Rhabdoviridae and Paramyxoviridae. Within the Rhabdoviridae, genome length can vary more than 40%, whereas variation within the Paramyxoviridae is no more than 5%. Thus, paramyxoviruses, especially those in the subfamily Paramyxovirinae, have traditionally been described as having a “uniform genome size” (23, 27). The universality of this feature is now challenged with the discovery, reported here, of a much larger genome for Hendra virus (HeV). Members of the family Paramyxoviridae include highly contagious human and animal pathogens such as human parainfluenza viruses, Measles virus, Canine distemper virus, Rinderpest virus, Mumps virus, Newcastle disease virus (NDV), Human respiratory syncytial virus, and Turkey rhinotracheitis virus. Classification within the family has undergone major changes in recent years, and the current taxonomy (17, 24, 27) divides the family into two subfamilies, Paramyxovirinae and Pneumovirinae. The Paramyxovirinae include three genera, Respirovirus (formerly known as Paramyxovirus), Morbillivirus, and Rubulavirus, whereas the Pneumovirinae contains two genera, Pneumovirus and Metapneumovirus. HeV was the causative agent of an explosive outbreak of a respiratory disease that resulted in the deaths of 14 horses and one human in a 2-week period in September 1994 in Hendra, a suburb of Brisbane, Australia (19). The virus was also responsible for a fatal human case of encephalitis in 1995, the infection almost certainly being acquired during necropsy of two horses that had died as a result of HeV infection 13 months previously (20). In January 1999, an additional fatal equine case was reported in North Queensland (13). Serological surveys and virus isolation studies indicated that flying foxes (fruit bats) in the genus Pteropus are likely to be the natural host of this new virus (11, 16, 34). In March 1999, a virus closely related to HeV emerged in Malaysia, spread rapidly via the respiratory route through the pig population, and caused the death by encephalitis of over 100 people. Efforts to control the spread of the pathogen, Nipah virus (NiV), included the culling of over 1 million pigs (5, 6). NiV is closely related to HeV, and antibodies raised against one virus can neutralize the other in serum neutralization tests, albeit with reduced efficiency (5, 12). Positive antibody responses to NiV have been recorded in the Malaysian fruit bat population (8). In addition to these two viruses, several other newly emerged Mononegavirales members of bat origin have been identified. These include Australian bat lyssavirus (9) and Menangle virus (21). Australian bat lyssavirus is closely related to rabies virus and was responsible for the death of a bat handler in 1996 (1). Menangle virus caused fetal death and abortion in pigs and respiratory disease in humans (4, 21). It appears to be a member of the Rubulavirus genus (M. Westenberg, personal communication). A new member of the Paramyxoviridae has recently been isolated from bat urine in Malaysia, and it displays some antigenic cross-reactivity with Menangle virus (K. Chua, personal communication). Tidona et al. (30) reported the isolation and characterization of a novel virus, Tupaia paramyxovirus (TPMV), from tree shrews, and Renshaw et al. (26) recently published the molecular characterization of the Salem virus, yet another novel paramyxovirus isolated from horses. These two new viruses are phylogenetically related to each other and to HeV and morbilliviruses. The isolation of seven new viruses, at least four of which are zoonotic and five of which appear to have originated from fruit bats, opens a new and exciting era in the investigation of the natural history of Paramyxoviridae and NNS RNA viruses in general. In this paper, we report the molecular characterization of the HeV L gene, which encodes the RNA polymerase, and determine the sequence of the genome termini and gene boundaries and thus complete the sequence of the largest genome in the Paramyxoviridae to be described. Important molecular features will be summarized to support the establishment of a new genus for HeV and NiV within the subfamily Paramyxovirinae.
Bryan T Eaton - One of the best experts on this subject based on the ideXlab platform.
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the complete genome sequence of j virus reveals a unique genome structure in the family Paramyxoviridae
Journal of Virology, 2005Co-Authors: Philippa J M Jack, Bryan T Eaton, David B Boyle, Linfa WangAbstract:J virus (J-V) was isolated from feral mice ( Mus musculus ) trapped in Queensland, Australia, during the early 1970s. Although studies undertaken at the time revealed that J-V was a new paramyxovirus, it remained unclassified beyond the family level. The complete genome sequence of J-V has now been determined, revealing a genome structure unique within the family Paramyxoviridae . At 18,954 nucleotides (nt), the J-V genome is the largest paramyxovirus genome sequenced to date, containing eight genes in the order 3′-N-P/V/C-M-F-SH-TM-G-L-5′. The two genes located between the fusion (F) and attachment (G) protein genes, which have been named the small hydrophobic (SH) protein gene and the transmembrane (TM) protein gene, encode putative proteins of 69 and 258 amino acids, respectively. The 4,401-nt J-V G gene, much larger than other paramyxovirus attachment protein genes sequenced to date, encodes a putative attachment protein of 709 amino acids and distally contains a second open reading frame (ORF) of 2,115 nt, referred to as ORF-X. Taken together, these novel features represent the most significant divergence to date from the common six-gene genome structure of Paramyxovirinae . Although genome analysis has confirmed that J-V can be classified as a member of the subfamily Paramyxovirinae , it cannot be assigned to any of the five existing genera within this subfamily. Interestingly, a recently isolated paramyxovirus appears to be closely related to J-V, and preliminary phylogenetic analyses based on putative matrix protein sequences indicate that these two viruses will likely represent a new genus within the subfamily Paramyxovirinae .
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tioman virus a novel paramyxovirus isolated from fruit bats in malaysia
Virology, 2001Co-Authors: Kaw Bing Chua, Linfa Wang, Meng Yu, Gary Crameri, David B Boyle, Terry G Wise, Alex D Hyatt, Bryan T EatonAbstract:Abstract A search for the natural host of Nipah virus has led to the isolation of a previously unknown member of the family Paramyxoviridae. Tioman virus (TiV) was isolated from the urine of fruit bats ( Pteropus hypomelanus ) found on the island of the same name off the eastern coast of peninsular Malaysia. An electron microscopic study of TiV-infected cells revealed spherical and pleomorphic-enveloped viral particles (100–500 nm in size) with a single fringe of embedded peplomers. Virus morphogenesis occurred at the plasma membrane of infected cells and morphological features of negative-stained ribonucleoprotein complexes were compatible with that of viruses in the family Paramyxoviridae. Serological studies revealed no cross-reactivity with antibodies against a number of known Paramyxoviridae members except for the newly described Menangle virus (MenV), isolated in Australia in 1997. Failure of PCR amplification using MenV-specific primers suggested that this new virus is related to but different from MenV. For molecular characterization of the virus, a cDNA subtraction strategy was employed to isolate virus-specific cDNA from virus-infected cells. Complete gene sequences for the nucleocapsid protein (N) and phosphoprotein (P/V) have been determined and recombinant N and V proteins produced in baculovirus. The recombinant N and V proteins reacted with porcine anti-MenV sera in Western blot, confirming the serological cross-reactivity observed during initial virus characterization. The lack of a C protein-coding region in the P/V gene, the creation of P mRNA by insertion of 2-G residues, and the results of phylogenetic analyses all indicated that TiV is a novel member of the genus Rubulavirus .
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the exceptionally large genome of hendra virus support for creation of a new genus within the family Paramyxoviridae
Journal of Virology, 2000Co-Authors: Linfa Wang, Meng Yu, Eric Hansson, Ian L Pritchard, Brian J Shiell, Wojtek P Michalski, Bryan T EatonAbstract:Although they manifest diverse biological properties, viruses in the families Filoviridae, Paramyxoviridae, Rhabdoviridae, and Bornaviridae all contain a nonsegmented negative-strand (NNS) RNA genome and share features of genome organization. These facts, together with similarities in domain structure and sequence of the viral polymerase proteins, suggest a close phylogenetic relationship. The four families are now grouped taxonomically in the order Mononegavirales, the first taxon above family level to be recognized in virus taxonomy (23, 25). The genome size of viruses in the order varies significantly, ranging from 8.9 kb in the Bornaviridae to 19.1 kb in the Filoviridae. Members of the Rhabdoviridae and Paramyxoviridae have intermediate genome sizes, 10.8 to 14.9 kb and 15.1 to 15.9 kb, respectively. Two interesting observations can be made from the comparison of genome sizes. First, there is no overlap of genome size between virus families. Second, genome size ranges differ significantly between the two families in which multiple genera have been defined, the Rhabdoviridae and Paramyxoviridae. Within the Rhabdoviridae, genome length can vary more than 40%, whereas variation within the Paramyxoviridae is no more than 5%. Thus, paramyxoviruses, especially those in the subfamily Paramyxovirinae, have traditionally been described as having a “uniform genome size” (23, 27). The universality of this feature is now challenged with the discovery, reported here, of a much larger genome for Hendra virus (HeV). Members of the family Paramyxoviridae include highly contagious human and animal pathogens such as human parainfluenza viruses, Measles virus, Canine distemper virus, Rinderpest virus, Mumps virus, Newcastle disease virus (NDV), Human respiratory syncytial virus, and Turkey rhinotracheitis virus. Classification within the family has undergone major changes in recent years, and the current taxonomy (17, 24, 27) divides the family into two subfamilies, Paramyxovirinae and Pneumovirinae. The Paramyxovirinae include three genera, Respirovirus (formerly known as Paramyxovirus), Morbillivirus, and Rubulavirus, whereas the Pneumovirinae contains two genera, Pneumovirus and Metapneumovirus. HeV was the causative agent of an explosive outbreak of a respiratory disease that resulted in the deaths of 14 horses and one human in a 2-week period in September 1994 in Hendra, a suburb of Brisbane, Australia (19). The virus was also responsible for a fatal human case of encephalitis in 1995, the infection almost certainly being acquired during necropsy of two horses that had died as a result of HeV infection 13 months previously (20). In January 1999, an additional fatal equine case was reported in North Queensland (13). Serological surveys and virus isolation studies indicated that flying foxes (fruit bats) in the genus Pteropus are likely to be the natural host of this new virus (11, 16, 34). In March 1999, a virus closely related to HeV emerged in Malaysia, spread rapidly via the respiratory route through the pig population, and caused the death by encephalitis of over 100 people. Efforts to control the spread of the pathogen, Nipah virus (NiV), included the culling of over 1 million pigs (5, 6). NiV is closely related to HeV, and antibodies raised against one virus can neutralize the other in serum neutralization tests, albeit with reduced efficiency (5, 12). Positive antibody responses to NiV have been recorded in the Malaysian fruit bat population (8). In addition to these two viruses, several other newly emerged Mononegavirales members of bat origin have been identified. These include Australian bat lyssavirus (9) and Menangle virus (21). Australian bat lyssavirus is closely related to rabies virus and was responsible for the death of a bat handler in 1996 (1). Menangle virus caused fetal death and abortion in pigs and respiratory disease in humans (4, 21). It appears to be a member of the Rubulavirus genus (M. Westenberg, personal communication). A new member of the Paramyxoviridae has recently been isolated from bat urine in Malaysia, and it displays some antigenic cross-reactivity with Menangle virus (K. Chua, personal communication). Tidona et al. (30) reported the isolation and characterization of a novel virus, Tupaia paramyxovirus (TPMV), from tree shrews, and Renshaw et al. (26) recently published the molecular characterization of the Salem virus, yet another novel paramyxovirus isolated from horses. These two new viruses are phylogenetically related to each other and to HeV and morbilliviruses. The isolation of seven new viruses, at least four of which are zoonotic and five of which appear to have originated from fruit bats, opens a new and exciting era in the investigation of the natural history of Paramyxoviridae and NNS RNA viruses in general. In this paper, we report the molecular characterization of the HeV L gene, which encodes the RNA polymerase, and determine the sequence of the genome termini and gene boundaries and thus complete the sequence of the largest genome in the Paramyxoviridae to be described. Important molecular features will be summarized to support the establishment of a new genus for HeV and NiV within the subfamily Paramyxovirinae.
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a novel p v c gene in a new member of the Paramyxoviridae family which causes lethal infection in humans horses and other animals
Journal of Virology, 1998Co-Authors: Linfa Wang, Meng Yu, Ian L Pritchard, Brian J Shiell, Wojtek P Michalski, Gary Crameri, Bryan T EatonAbstract:In 1994, a new member of the family Paramyxoviridae isolated from fatal cases of respiratory disease in horses and humans was shown to be distantly related to morbilliviruses and provisionally called equine morbillivirus (K. Murray et al., Science 268:94–97, 1995). To facilitate characterization and classification, the virus was purified, viral proteins were identified, and the P/V/C gene was cloned and sequenced. The coding strategy of the gene is similar to that of Sendai and measles viruses, members of the Paramyxovirus and Morbillivirus genera, respectively, in the subfamily Paramyxovirinae . The P/V/C gene contains four open reading frames, three of which, P, C, and V, have Paramyxovirinae counterparts. The P and C proteins are larger and smaller, respectively, than are cognate proteins in members of the subfamily, and the V protein is made as a result of a single G insertion during transcription. The P/V/C gene has two unique features. (i) A fourth open reading frame is located between those of the C and V proteins and potentially encodes a small basic protein similar to those found in some members of the Rhabdoviridae and Filoviridae families. (ii) There is also a long untranslated 3′ sequence, a feature common in Filoviridae members. Sequence comparisons confirm that although the virus is a member of the Paramyxovirinae subfamily, it displays only low levels of homology with paramyxoviruses and morbilliviruses and negligible homologies with rubulaviruses.
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flying foxes horses and humans a zoonosis caused by a new member of the Paramyxoviridae
1998Co-Authors: Keith Murray, Linfa Wang, Bryan T Eaton, P T Hooper, M M Williamson, P L YoungAbstract:This chapter describes the outbreaks of disease caused by Megamyxovirus zoonotic agent; provides an updated description of the virus, its genome, and its wildlife reservoir; and documents what is known of the pathology and pathogenesis of equine morbillivirus (EMV) infection. A severe outbreak of respiratory disease occurred in the second half of September 1994 in horses stabled in the Brisbane suburb of Hendra. The outcome of the outbreak was that 13 horses died. The trainer died after hospitalization with severe respiratory involvement, while the stable hand recovered after a protracted illness. Although horses had been moved off the property during this period, infection had not spread to distant sites and extensive surveillance showed that the virus was not active in horses or humans. In fluorescent-antibody tests, sera from naturally infected horses and humans reacted strongly with the fruit bat virus. Identical viruses were isolated from a range of tissues from horses infected during the initial outbreak and from a kidney of the deceased trainer. Morphologically the virus is a member of the family Paramyxoviridae. The pathology of field and experimental EMV infections in horses and experimental infections in cats has been described. It is sufficiently different from known members of the Paramyxoviridae to be considered a member of a new genus which bridges the two existing genera Paramyxovirus and Morbillivirus. The author proposes that consideration should be given to creating a new genus within the family Paramyxoviridae, subfamily Paramyxovirinae, to be called Megamyxovirus, with the type species being EMV.
Bruce S. Seal - One of the best experts on this subject based on the ideXlab platform.
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nucleotide sequence analysis of the newcastle disease virus nucleocapsid protein gene and phylogenetic relationships among the Paramyxoviridae
Virus Research, 2002Co-Authors: Bruce S. Seal, Holly S. Sellers, John M Crawford, Devin P Locke, Daniel J KingAbstract:The nucleocapsid (N) protein genes from 24 Newcastle disease virus (NDV) isolates representing various pathotypes with different geographical and chronological origins were cloned and sequenced. The N-terminal region of the N protein to residue 401 was highly conserved among isolates with several conservative substitutions occurring that correlated with phylogenetic relationships. Variability of the N protein was detected in the C-terminal portion similar to what has been reported for other members of the Paramyxovirinae. Amino acids previously identified as invariant or highly conserved in N proteins of other paramyxoviruses were also present in the NDV protein. Phylogenetic analysis of N gene coding sequences among NDV isolates again demonstrated the existence of two major groups. One clade contained viruses that included vaccine and virulent strains isolated in the USA prior to 1970 while a second clade included vaccine and virulent viruses isolated worldwide. Comparison of N protein amino acid sequences among members of the Paramyxoviridae resulted in NDV and avian paramyxovirus 6 separating as a cluster distinct from the Rubulavirus genus. This provides further support for avian paramyxoviruses being considered for their own genus among the Paramyxovirinae.
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The avian response to Newcastle disease virus
Developmental and Comparative Immunology, 2000Co-Authors: Bruce S. Seal, Daniel J King, Holly S. SellersAbstract:Newcastle disease virus (NDV) is classified as a member of the superfamily Mononegavirales in the family Paramyxoviridae. This virus family is divided into two subfamilies, the Paramyxovirinae and the Pneumovirinae. In 1993 the International Committee on the Taxonomy of Viruses rearranged the order of the Paramyxovirus genus and placed NDV within the Rubulavirus genus among the Paramyxovirinae. The enveloped virus has a negative sense single- stranded RNA genome of 15,186 kb which codes for an RNA directed RNA polymerase, hemagglutinin-neuraminidase protein, fusion protein, matrix protein, phosphoprotein and nucleoprotein in the 5' to 3' direction. The virus has a wide host range with most orders of birds reported to have been infected by NDV. Isolates are characterized by virulence in chickens and are categorized into three main pathotypes depending on severity of disease. Lentogenic isolates are of low virulence while viruses of intermediate virulence are termed mesogenic. Highly virulent viruses that cause high mortality in birds are termed neurotropic or viscerotropic velogenic. Velogenic NDV are List A pathogens that require reporting to the Office of International Epizootics and outbreaks result in strict trade embargoes. The primary molecular determinant for NDV pathogenicity is the fusion protein cleavage site amino acid sequence. Vaccination for NDV is primarily by mass application of live-virus vaccines among commercial poultry. Although protection is measured by presence of antibodies to NDV, vaccinated B-cell depleted chickens are resistant to disease. Consequently, immune protection involves responses that are presently incompletely defined. (C) 2000 Elsevier Science Ltd.
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molecular evolution of the newcastle disease virus matrix protein gene and phylogenetic relationships among the Paramyxoviridae
Virus Research, 2000Co-Authors: Bruce S. Seal, Daniel J King, Richard J MeinersmannAbstract:Matrix (M) gene sequences for recent field isolates and older reference Newcastle disease viruses (NDV) were examined to determine phylogenetic relationships and population trends among these viruses. Overall, the M gene has a majority of synonymous nucleotide sequence substitutions occurring among NDV isolates. However, several predicted amino acid changes in the M protein of specific NDV isolates have occurred that correlate to phylogenetic relationships. Nucleotide substitutions in these codons have a greater number of nonsynonymous base changes. The NDV isolates arising since the 1970s belong to a population of viruses that expanded worldwide at an exponential rate. These viruses may have their origins in free-living birds, are present worldwide, and continue to circulate causing disease in poultry. A specific NDV lineage composed of virulent isolates obtained in the US prior to 1970 appears to no longer exists among free-living birds or commercial poultry. However, ‘‘vaccine-like’’ viruses are common in the US and continue to circulate among commercial poultry. Based on M protein amino acid sequences, NDV separates as a clade most closely related to morbilliviruses and not with their current designated category, the rubulaviruses among the Paramyxoviridae. Consequently, avian paramyxoviruses should have their own taxonomic subfamily among the Paramyxovirinae. © 2000 Elsevier Science B.V. All rights reserved.
Daniel J King - One of the best experts on this subject based on the ideXlab platform.
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nucleotide sequence analysis of the newcastle disease virus nucleocapsid protein gene and phylogenetic relationships among the Paramyxoviridae
Virus Research, 2002Co-Authors: Bruce S. Seal, Holly S. Sellers, John M Crawford, Devin P Locke, Daniel J KingAbstract:The nucleocapsid (N) protein genes from 24 Newcastle disease virus (NDV) isolates representing various pathotypes with different geographical and chronological origins were cloned and sequenced. The N-terminal region of the N protein to residue 401 was highly conserved among isolates with several conservative substitutions occurring that correlated with phylogenetic relationships. Variability of the N protein was detected in the C-terminal portion similar to what has been reported for other members of the Paramyxovirinae. Amino acids previously identified as invariant or highly conserved in N proteins of other paramyxoviruses were also present in the NDV protein. Phylogenetic analysis of N gene coding sequences among NDV isolates again demonstrated the existence of two major groups. One clade contained viruses that included vaccine and virulent strains isolated in the USA prior to 1970 while a second clade included vaccine and virulent viruses isolated worldwide. Comparison of N protein amino acid sequences among members of the Paramyxoviridae resulted in NDV and avian paramyxovirus 6 separating as a cluster distinct from the Rubulavirus genus. This provides further support for avian paramyxoviruses being considered for their own genus among the Paramyxovirinae.
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The avian response to Newcastle disease virus
Developmental and Comparative Immunology, 2000Co-Authors: Bruce S. Seal, Daniel J King, Holly S. SellersAbstract:Newcastle disease virus (NDV) is classified as a member of the superfamily Mononegavirales in the family Paramyxoviridae. This virus family is divided into two subfamilies, the Paramyxovirinae and the Pneumovirinae. In 1993 the International Committee on the Taxonomy of Viruses rearranged the order of the Paramyxovirus genus and placed NDV within the Rubulavirus genus among the Paramyxovirinae. The enveloped virus has a negative sense single- stranded RNA genome of 15,186 kb which codes for an RNA directed RNA polymerase, hemagglutinin-neuraminidase protein, fusion protein, matrix protein, phosphoprotein and nucleoprotein in the 5' to 3' direction. The virus has a wide host range with most orders of birds reported to have been infected by NDV. Isolates are characterized by virulence in chickens and are categorized into three main pathotypes depending on severity of disease. Lentogenic isolates are of low virulence while viruses of intermediate virulence are termed mesogenic. Highly virulent viruses that cause high mortality in birds are termed neurotropic or viscerotropic velogenic. Velogenic NDV are List A pathogens that require reporting to the Office of International Epizootics and outbreaks result in strict trade embargoes. The primary molecular determinant for NDV pathogenicity is the fusion protein cleavage site amino acid sequence. Vaccination for NDV is primarily by mass application of live-virus vaccines among commercial poultry. Although protection is measured by presence of antibodies to NDV, vaccinated B-cell depleted chickens are resistant to disease. Consequently, immune protection involves responses that are presently incompletely defined. (C) 2000 Elsevier Science Ltd.
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molecular evolution of the newcastle disease virus matrix protein gene and phylogenetic relationships among the Paramyxoviridae
Virus Research, 2000Co-Authors: Bruce S. Seal, Daniel J King, Richard J MeinersmannAbstract:Matrix (M) gene sequences for recent field isolates and older reference Newcastle disease viruses (NDV) were examined to determine phylogenetic relationships and population trends among these viruses. Overall, the M gene has a majority of synonymous nucleotide sequence substitutions occurring among NDV isolates. However, several predicted amino acid changes in the M protein of specific NDV isolates have occurred that correlate to phylogenetic relationships. Nucleotide substitutions in these codons have a greater number of nonsynonymous base changes. The NDV isolates arising since the 1970s belong to a population of viruses that expanded worldwide at an exponential rate. These viruses may have their origins in free-living birds, are present worldwide, and continue to circulate causing disease in poultry. A specific NDV lineage composed of virulent isolates obtained in the US prior to 1970 appears to no longer exists among free-living birds or commercial poultry. However, ‘‘vaccine-like’’ viruses are common in the US and continue to circulate among commercial poultry. Based on M protein amino acid sequences, NDV separates as a clade most closely related to morbilliviruses and not with their current designated category, the rubulaviruses among the Paramyxoviridae. Consequently, avian paramyxoviruses should have their own taxonomic subfamily among the Paramyxovirinae. © 2000 Elsevier Science B.V. All rights reserved.
Mark S. Galinski - One of the best experts on this subject based on the ideXlab platform.
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The Molecular Biology of the Paramyxovirus Genus
The Paramyxoviruses, 1991Co-Authors: Mark S. Galinski, Steven L. WechslerAbstract:The Paramyxovirus genus, one of the three genera classified in the family Paramyxoviridae, contains a number of important viruses causing disease in humans and other animals (Table I). Historically parainfluenza, mumps, and Newcastle disease viruses were assigned to the Myxoviridae group based upon common biological properties shared with the influenza viruses (Andrewes et al., 1955; Chanock, 1956; Chanock et al., 1958). However, later studies indicated sufficient biochemical differences, in particular, the molecular organization of the genomes (segmented versus nonsegmented) and the melding of neuraminidase and hemagglutinating activities into a single glycoprotein (paramyxoviruses) versus separate glycoproteins (influenza virus), to reclassify both groups of viruses into the separate taxons Paramyxoviridae and Orthomyxoviridae (Waterson, 1962; Wildy 1971). A number of viruses, including measles, canine distemper, respiratory syncytial, and mouse pneumonia viruses, do not share cross-reactive antigens with other Paramyxoviridae. However, because of their morphological and biochemical characteristics, they were classified in the Paramyxoviridae family as separate genera (Kingsbury et al., 1978a).
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Paramyxoviridae transcription and replication
Advances in Virus Research, 1991Co-Authors: Mark S. GalinskiAbstract:Publisher Summary Nonsegmented negative-strand RNA viruses are a unique group of infectious agents that require active transcription of their genomic single-stranded RNA as a prerequisite for replication following penetration into a susceptible host cell. Currently, there are three viral families whose genomic organization and polarity provide for their inclusion in this group: the Paramyxoviridae, Rhabdoviridae, and the recently recognized Filoviridae. Despite differences in the number and types of genedproteins present in these viruses, members of all three taxons need to address similar replicative problems. They need to transcribe and translate mRNAs, replicate the single-stranded RNA genome, encapsidate progeny RNA with nucleocapsid proteins, and assemble and export mature virions; these are processes critically dependent on viral gene expression. Despite their fairly simple molecular organization, these viruses have evolved rather elaborate systems for their replication. Rather than contrast the various molecular processes employed by the three taxons for replication and transcription, this chapter focuses on the current understanding of processes employed by Paramyxoviridae.