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Ian Goodfellow - One of the best experts on this subject based on the ideXlab platform.

  • calicivirus vp2 forms a portal to mediate endosome escape
    bioRxiv, 2018
    Co-Authors: Michaela J Conley, Ian Goodfellow, Marion Mcelwee, Liyana Azmi, Mads Gabrielsen, Olwyn Byron, David Bhella
    Abstract:

    To initiate the infectious process, many viruses enter their host cells by triggering endocytosis following receptor engagement. The mechanism by which non-enveloped viruses, such as the caliciviruses, escape the endosome is however poorly understood. The Caliciviridae include many important human and animal pathogens, most notably norovirus, the cause of winter vomiting disease. Here we show that VP2, a minor capsid protein encoded by all caliciviruses, forms a large portal assembly at a unique three-fold symmetry axis following receptor engagement. This feature surrounds an open pore in the capsid shell. We hypothesise that the VP2 portal complex is the means by which the virus escapes the endosome, penetrating the endosomal membrane to release the viral genome into the cytoplasm. Cryogenic electron microscopy (cryoEM) and asymmetric reconstruction were used to investigate structural changes in the capsid of feline calicivirus (FCV) that occur when the virus binds to its cellular receptor junctional adhesion molecule-A (fJAM-A). Near atomic-resolution structures were calculated for the native virion alone and decorated with soluble receptor fragments. We present atomic models of the major capsid protein VP1 in the presence and absence of fJAM-A, revealing the contact interface and conformational changes brought about by the interaction. Furthermore, we have calculated an atomic model of the portal protein VP2 and revealed the structural changes in VP1 that lead to pore formation. While VP2 was known to be critical for the production of infectious virus, its function has been hitherto undetermined. Our finding that VP2 assembles a portal that is likely responsible for endosome escape represents a major step forward in our understanding of both the Caliciviridae and icosahedral RNA containing viruses in general.

  • vesivirus 2117 capsids more closely resemble sapovirus and lagovirus particles than other known vesivirus structures
    Journal of General Virology, 2017
    Co-Authors: Michaela J Conley, Ian Goodfellow, Edward Emmott, Richard J Orton, David W Taylor, Daniel Goncalves Carneiro, Grant S Hansman, Kazuyoshi Murata, David Bhella
    Abstract:

    Vesivirus 2117 is an adventitious agent that, in 2009, was identified as a contaminant of Chinese hamster ovary cells propagated in bioreactors at a pharmaceutical manufacturing plant belonging to Genzyme. The consequent interruption in supply of Fabrazyme and Cerezyme (drugs used to treat Fabry and Gaucher diseases, respectively) caused significant economic losses. Vesivirus 2117 is a member of the Caliciviridae, a family of small icosahedral viruses encoding a positive-sense RNA genome. We have used cryo-electron microscopy and three-dimensional image reconstruction to calculate a structure of vesivirus 2117 virus-like particles as well as feline calicivirus and a chimeric sapovirus. We present a structural comparison of several members of the Caliciviridae, showing that the distal P domain of vesivirus 2117 is morphologically distinct from that seen in other known vesivirus structures. Furthermore, at intermediate resolutions, we found a high level of structural similarity between vesivirus 2117 and Caliciviridae from other genera: sapovirus and rabbit hemorrhagic disease virus. Phylogenetic analysis confirms vesivirus 2117 as a vesivirus closely related to canine vesiviruses. We postulate that morphological differences in virion structure seen between vesivirus clades may reflect differences in receptor usage.

  • Functions of the 5' and 3' ends of calicivirus genomes
    Virus research, 2015
    Co-Authors: Bader Alhatlani, Surender Vashist, Ian Goodfellow
    Abstract:

    The Caliciviridae family of small positive sense RNA viruses contains a diverse range of pathogens of both man and animals. The molecular mechanisms of calicivirus genome replication and translation have not been as widely studied as many other RNA viruses. With the relatively recent development of robust cell culture and reverse genetics systems for several members of the Caliciviridae family, a more in-depth analysis of the finer detail of the viral life cycle has now been obtained. As a result, the identification and characterization of the role of RNA structures in the calicivirus life cycle has also been possible. This review aims to summarize the current state of knowledge with respect to the role of RNA structures at the termini of calicivirus genomes.

  • the genome linked protein vpg of vertebrate viruses a multifaceted protein
    Current Opinion in Virology, 2011
    Co-Authors: Ian Goodfellow
    Abstract:

    Several vertebrate positive-sense RNA viruses, namely the Picornaviridae and Caliciviridae have evolved to use a protein-primed mechanism of genome replication. This results in the covalent linkage of a virus encoded protein, VPg (viral protein genome-linked), to the 5′ end of viral RNA. Recent studies have highlighted the pivotal role VPg plays in the life cycle of these viruses, which in the case of the Caliciviridae, includes a role in viral protein synthesis. This article provides an overview of the current knowledge of the functions of vertebrate RNA virus VPg proteins, illustrating their diverse function and the parallels they share with plant virus VPg proteins.

  • The genome-linked protein VPg of vertebrate viruses — a multifaceted protein
    Current Opinion in Virology, 2011
    Co-Authors: Ian Goodfellow
    Abstract:

    Several vertebrate positive-sense RNA viruses, namely the Picornaviridae and Caliciviridae have evolved to use a protein-primed mechanism of genome replication. This results in the covalent linkage of a virus encoded protein, VPg (viral protein genome-linked), to the 5′ end of viral RNA. Recent studies have highlighted the pivotal role VPg plays in the life cycle of these viruses, which in the case of the Caliciviridae, includes a role in viral protein synthesis. This article provides an overview of the current knowledge of the functions of vertebrate RNA virus VPg proteins, illustrating their diverse function and the parallels they share with plant virus VPg proteins.

Kim Y. Green - One of the best experts on this subject based on the ideXlab platform.

  • ICTV Virus Taxonomy Profile: Caliciviridae.
    The Journal of general virology, 2019
    Co-Authors: Jan Vinjé, Kim Y. Green, Mary K. Estes, Pedro J. Esteves, Kazuhiko Katayama, Nick J. Knowles, Yvan L’homme, Vito Martella, Harry Vennema, Peter A. White
    Abstract:

    The family Caliciviridae includes viruses with single-stranded, positive-sense RNA genomes of 7.4–8.3 kb. The most clinically important representatives are human noroviruses, which are a leading cause of acute gastroenteritis in humans. Virions are non-enveloped with icosahedral symmetry. Members of seven genera infect mammals (Lagovirus, Norovirus, Nebovirus, Recovirus, Sapovirus, Valovirus and Vesivirus), members of two genera infect birds (Bavovirus and Nacovirus), and members of two genera infect fish (Minovirus and Salovirus). This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Caliciviridae, which is available at ictv.global/report/Caliciviridae.

  • Genetic characterization of a reptilian calicivirus (Cro1)
    Virology Journal, 2012
    Co-Authors: Carlos Sandoval-jaime, Kim Y. Green, Gabriel I Parra, Alvin W. Smith, Stanislav V. Sosnovtsev
    Abstract:

    Background Vesiviruses in the family Caliciviridae infect a broad range of animal hosts including mammals, birds, fish, amphibians and reptiles. The vesivirus Cro1 strains were isolated from diseased snakes in the San Diego zoo in 1978 and reported as the first caliciviruses found in reptiles. The goal of this study was to characterize the Cro1 strain 780032I that was isolated in cell culture from a rock rattlesnake (Crotalus lepidus) in the original outbreak.

  • reverse genetics system for porcine enteric calicivirus a prototype sapovirus in the Caliciviridae
    Journal of Virology, 2005
    Co-Authors: Kyeong-ok Chang, Stanislav V. Sosnovtsev, Linda J. Saif, Qiuhong Wang, Gael Belliot, Kim Y. Green
    Abstract:

    A porcine enteric calicivirus (PEC), strain Cowden in the genus Sapovirus of the Caliciviridae family, can be propagated in a porcine kidney continuous cell line (LLC-PK) in the presence of bile acids in the cell culture medium. A full-length cDNA copy of the Cowden PEC genome was cloned into a plasmid vector directly downstream from the T7 RNA polymerase promoter, and capped RNA transcripts derived from this clone were infectious when transfected into LLC-PK cells. The recovery of PEC after transfection of RNA transcripts was dependent on the presence of bile acids, consistent with our recent identification of a bile acid-mediated signaling pathway required for PEC replication (Chang et al., Proc. Natl. Acad. Sci. USA 101:8733-8788, 2004). Recovery of virus was verified by detection of PEC antigen in transfected cells by immunofluorescence and enzyme-linked immunosorbent assays, direct observation of recovered viral particles by electron microscopy, and partial sequence analysis of their genomes (first 1,070 nucleotides) to differentiate them from tissue culture-adapted parental virus. The recovered virus retained its ability to infect piglets when administered by the oral route and showed an attenuated phenotype similar to that of the tissue culture-adapted parental virus. This reverse genetics system for PEC provides a new tool to study the molecular basis of replication and pathogenesis for caliciviruses associated with diarrheal disease.

  • Taxonomy of the caliciviruses.
    The Journal of Infectious Diseases, 2000
    Co-Authors: Kim Y. Green, David O Matson, Tamie Ando, M. S. Balayan, Tamas Berke, Shuji Nakata, John D. Neill, Ian N. Clarke, Mary K. Estes, Michael J. Studdert
    Abstract:

    The International Committee on Taxonomy of Viruses (ICTV) has recently approved several proposals submitted by the present Caliciviridae Study Group. These proposals include the division of the family into 4 new genera designated Lagovirus, Vesivirus, "Norwalk-like viruses (NLVs), and "Sapporo-like viruses (SLVs); the latter 2 genera were assigned temporary names until acceptable names can be determined by the scientific community. The genera have been further divided into the following species: Feline calicivirus and Vesicular exanthema of swine virus (genus Vesivirus), Rabbit hemorrhagic disease virus and European brown hare syndrome virus (genus Lagovirus), Norwalk virus (genus NLV), and Sapporo virus (genus SLV). In addition, the ICTV approved a proposal to remove the hepatitis E virus from the Caliciviridae into an "unassigned classification status.

  • Expression and self-assembly of recombinant capsid protein from the antigenically distinct Hawaii human calicivirus.
    Journal of clinical microbiology, 1997
    Co-Authors: Kim Y. Green, Jose Valdesuso, Albert Z Kapikian, Stanislav V. Sosnovtsev, John J. Treanor, Judy F. Lew
    Abstract:

    The Norwalk and Hawaii viruses are antigenically distinct members of the family Caliciviridae and are considered to be important etiologic agents of epidemic gastroenteritis, with most studies focusing on the role of Norwalk virus. To further investigate the importance of Hawaii virus, Hawaii virus-like particles (VLPs) were produced by expression of its capsid protein in the baculovirus system and these VLPs were used as the antigen in an enzyme-linked immunosorbent assay that was efficient in the detection of a serologic response to Hawaii virus. The ready availability of Hawaii VLPs should enable larger-scale epidemiological studies to further elucidate the importance of this agent.

J.c. Bridger - One of the best experts on this subject based on the ideXlab platform.

  • characterisation of the bovine enteric calici like virus newbury agent 1
    Fems Microbiology Letters, 2000
    Co-Authors: Akbar M Dastjerdi, David R Snodgrass, J.c. Bridger
    Abstract:

    The bovine enteric calici-like virus, Newbury agent 1 (NA1) was characterised to determine if it is a member of the Caliciviridae and to establish its antigenic relationship to the established bovine enteric calicivirus Newbury agent 2 (NA2). Solid phase immune electron microscopy (SPIEM) allowed quantification of NA1 virions and identification of faecal samples with optimal virus levels. NA1 particles were 36.6 nm in diameter, had an indefinite surface structure resembling that of human small round structured viruses (SRSVs), and a buoyant density of 1.34 g ml−1. A single capsid protein of 49.4 kDa was detected by Western blotting in purified NA1 preparations prepared from post-infection but not pre-infection faecal samples and with post- but not pre-infection sera. NA1 was antigenically unrelated to the bovine enteric calicivirus NA2 by SPIEM. These properties were consistent with classification of NA1 within the Caliciviridae but demonstrated heterogeneity in the capsid composition of bovine enteric caliciviruses.

  • characterisation of the bovine enteric calici like virus newbury agent 1
    Fems Microbiology Letters, 2000
    Co-Authors: Akbar M Dastjerdi, David R Snodgrass, J.c. Bridger
    Abstract:

    The bovine enteric calici-like virus, Newbury agent 1 (NA1) was characterised to determine if it is a member of the Caliciviridae and to establish its antigenic relationship to the established bovine enteric calicivirus Newbury agent 2 (NA2). Solid phase immune electron microscopy (SPIEM) allowed quantification of NA1 virions and identification of faecal samples with optimal virus levels. NA1 particles were 36.6 nm in diameter, had an indefinite surface structure resembling that of human small round structured viruses (SRSVs), and a buoyant density of 1.34 g ml−1. A single capsid protein of 49.4 kDa was detected by Western blotting in purified NA1 preparations prepared from post-infection but not pre-infection faecal samples and with post- but not pre-infection sera. NA1 was antigenically unrelated to the bovine enteric calicivirus NA2 by SPIEM. These properties were consistent with classification of NA1 within the Caliciviridae but demonstrated heterogeneity in the capsid composition of bovine enteric caliciviruses.

  • The Bovine Newbury Agent-2 Is Genetically More Closely Related to Human SRSVs Than to Animal Caliciviruses
    Virology, 1999
    Co-Authors: A.m. Dastjerdi, Jonathan Green, Chris I. Gallimore, David Brown, J.c. Bridger
    Abstract:

    Abstract The hypothesis that the enteric bovine calici-like virus Newbury agent (NA-2) belongs to the family Caliciviridae was examined by genome sequence analysis. Use of solid-phase immune electron microscopy allowed samples with good levels of virus to be identified and amplification of the genome was achieved by reverse transcription–polymerase chain reaction. Examination of a 216-amino-acid sequence in the RNA-dependent RNA polymerase gene and a 116-amino-acid sequence in the capsid gene showed that NA-2 had the closest deduced amino acid identity (77 to 80% for the polymerase region and 67 to 73% for the capsid region) to the morphologically indistinguishable human SRSVs (small round structured viruses) of genogroup 1, which are classified as members of the Caliciviridae. It had a weak relationship ( Caliciviridae and endorses the observation to date that viruses with SRSV morphology are genomically distinct.

Xi Jiang - One of the best experts on this subject based on the ideXlab platform.

  • Recovery of Infectious Virus by Transfection of In Vitro-Generated RNA from Tulane Calicivirus cDNA
    Journal of Virology, 2008
    Co-Authors: Tibor Farkas, Karol Sestak, Xi Jiang
    Abstract:

    Tulane virus (TV) is a newly reported calicivirus that was isolated from stool samples of captive rhesus macaques from the Tulane National Primate Research Center (TNPRC). The virus has been cultivated successfully in LLC-MK2 rhesus monkey kidney cells. Its complete genomic sequence suggests that TV represents a new genus and is evolutionarily more closely related to Norovirus than to any other genus of Caliciviridae. In this study, we demonstrated that RNA transcripts made in vitro from the full-length genomic cDNA of TV were infectious upon transfection into permissive LLC-MK2 cells. The recombinant virus exhibited plaque morphologies and growth kinetics similar to those of the wild-type virus in this cell line. Capping was required for TV RNA infectivity. Although a subgenomic RNA has been detected in TV-transfected cells, a separate subgenomic RNA transcript was not required for the initial transfection to establish the replication. Transfection of truncated RNA lacking open reading frame 2 (ORF2) and ORF3 or TV-norovirus chimeric RNA resulted in abortive replication without the production of infectious progeny viruses, indicating that both ORFs are essential for the replication of TV. A heterologous insertion at the 5 end of the genome also hampered viral replication, suggesting that an authentic 5 end of the genome is critical for replication. The availability of the complete genomic sequence and the reverse genetics system described herein make TV a valuable model for studying calicivirus pathogenesis and replication. Caliciviruses (CVs) are important human and animal pathogens causing a wide variety of diseases, including respiratory infections, vesicular lesions, gastroenteritis, and hemorrhagic disease. Caliciviridae consists of four well-defined genera, Norovirus, Sapovirus, Lagovirus, and Vesivirus (9, 10), and a newly proposed genus, “Becovirus,” or “Nabovirus,” represented by bovine enteropathogenic CVs (Newbury agent 1 and Nebraska) (17, 18, 20). The Tulane virus (TV) that was recently discovered by our group represents a putative sixth genus of Caliciviridae, with a proposed name of “Recovirus” (7).

  • characterization of a rhesus monkey calicivirus representing a new genus of Caliciviridae
    Journal of Virology, 2008
    Co-Authors: Tibor Farkas, Karol Sestak, Xi Jiang, Chao Wei
    Abstract:

    In this study, we report the characterization of a novel calicivirus (CV), the Tulane virus (TV), which was isolated from stool samples of captive juvenile rhesus macaques (Macaca mulatta) of the Tulane National Primate Research Center. The complete genome of TV contains 6,714 nucleotides plus a poly(A) tail and is organized into three open reading frames (ORFs) that encode the nonstructural (NS) polyprotein (ORF1); the capsid protein (ORF2), with an estimated molecular mass of 57.9 kDa; and a possible minor structural protein (ORF3), with an isoelectric point (pI) of 10.0 and a calculated molecular mass of 22.8 kDa. The NS polyprotein revealed all typical CV amino acid motifs, including GXXGXGKT (NTPase), EYXEX (Vpg), GDCG (protease), and GLPSG and YGDD (polymerase). Phylogenetic trees constructed for the NS polyprotein, NTPase, protease, polymerase, and capsid protein sequences consistently placed the TV on a branch rooted with Norovirus, but with distances equal to those between other genera. The TV can be cultured in a monkey kidney cell line (LLC-MK2) with the appearance of typical cytopathic effect. TV exhibits a typical CV morphology, with a diameter of 36 nm, and has a buoyant density of 1.37 g/ml. According to these physicochemical and genetic characteristics, TV represents a new CV genus for which we propose the name “Recovirus” (rhesus enteric CV). Although the pathogenicity of TV in rhesus macaques remains to be elucidated, the likelihood of TV causing intestinal infection and the availability of a tissue culture system make this virus a valuable surrogate for human CVs.

  • identification of minireovirus as a norwalk like virus in pediatric patients with gastroenteritis
    Journal of Virology, 1994
    Co-Authors: M Petric, Albert Z Kapikian, Xi Jiang, Mary K. Estes, Kim Y. Green
    Abstract:

    Abstract In 1977, 30- to 32-nm virus-like particles, named minireovirus because of their unique morphologic appearance, were detected by electron microscopy in the stools of infants and young children with gastroenteritis. Sequence analysis of approximately 2,800 consecutive bases derived from overlapping PCR clones of a recent minireovirus clinical isolate showed 52% nucleotide sequence identity with the Norwalk virus sequence and, in addition, demonstrated that the genomic organizations of these two viruses were similar. Our data show that minireovirus is a Norwalk-like virus and should now also be included in the Caliciviridae family.

Joana Abrantes - One of the best experts on this subject based on the ideXlab platform.