Abstract:
UNLABELLED:Giardia lamblia virus (GLV) is a small, nonenveloped, nonsegmented double-stranded RNA (dsRNA) virus infecting Giardia lamblia, the most common protozoan pathogen of the human intestine and a major agent of waterborne diarrheal disease worldwide. GLV (genus Giardiavirus) is a member of family Totiviridae, along with several other groups of protozoal or fungal viruses, including Leishmania RNA viruses and Trichomonas vaginalis viruses. Interestingly, GLV is more closely related than other Totiviridae members to a group of recently discovered metazoan viruses that includes penaeid shrimp infectious myonecrosis virus (IMNV). Moreover, GLV is the only known protozoal dsRNA virus that can transmit efficiently by extracellular means, also like IMNV. In this study, we used transmission electron cryomicroscopy and icosahedral image reconstruction to examine the GLV virion at an estimated resolution of 6.0 Å. Its outermost diameter is 485 Å, making it the largest totivirus capsid analyzed to date. Structural comparisons of GLV and other totiviruses highlighted a related "T=2" capsid organization and a conserved helix-rich fold in the capsid subunits. In agreement with its unique capacity as a protozoal dsRNA virus to survive and transmit through extracellular environments, GLV was found to be more thermoresistant than Trichomonas vaginalis virus 1, but no specific protein machinery to mediate cell entry, such as the fiber complexes in IMNV, could be localized. These and other structural and biochemical findings provide a basis for future work to dissect the cell entry mechanism of GLV into a "primitive" (early-branching) eukaryotic host and an important enteric pathogen of humans. IMPORTANCE:Numerous pathogenic bacteria, including Corynebacterium diphtheriae, Salmonella enterica, and Vibrio cholerae, are infected with lysogenic bacteriophages that contribute significantly to bacterial virulence. In line with this phenomenon, several pathogenic protozoa, including Giardia lamblia, Leishmania species, and Trichomonas vaginalis are persistently infected with dsRNA viruses, and growing evidence indicates that at least some of these protozoal viruses can likewise enhance the pathogenicity of their hosts. Understanding of these protozoal viruses, however, lags far behind that of many bacteriophages. Here, we investigated the dsRNA virus that infects the widespread enteric parasite Giardia lamblia. Using electron cryomicroscopy and icosahedral image reconstruction, we determined the virion structure of Giardia lamblia virus, obtaining new information relating to its assembly, stability, functions in cell entry and transcription, and similarities and differences with other dsRNA viruses. The results of our study set the stage for further mechanistic work on the roles of these viruses in protozoal virulence.
journal_name
J Viroljournal_title
Journal of virologyauthors
Janssen ME,Takagi Y,Parent KN,Cardone G,Nibert ML,Baker TSdoi
10.1128/JVI.02745-14subject
Has Abstractpub_date
2015-01-15 00:00:00pages
1182-94issue
2eissn
0022-538Xissn
1098-5514pii
JVI.02745-14journal_volume
89pub_type
杂志文章abstract::The susceptibility to tumors induced by raf and raf/myc retroviruses was investigated in BALB/c, C57BL/6, (BALB/c x C57BL/6)F1 and (BALB/c x C57BL/6) backcross mice. Newborn mice were susceptible to neoplasms generated by both viruses, but resistance to raf-induced leukemia developed rapidly in all mice as they mature...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.63.5.2411-2414.1989
更新日期:1989-05-01 00:00:00
abstract::There is an incomplete understanding of the differences between neonatal immune responses that contribute to the increased susceptibility of neonates to some viral infections. We tested the hypothesis that neonates are more susceptible than adults to mouse adenovirus type 1 (MAV-1) respiratory infection and are impair...
journal_title:Journal of virology
pub_type: 杂志文章
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journal_title:Journal of virology
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.58.3.970-974.1986
更新日期:1986-06-01 00:00:00
abstract::Procedures for characterizing replication-defective viruses in nonpermissive mammalian cells were developed and applied to three nonvirogenic Rous sarcoma virus (RSV)-transformed mammalian cell lines--B4, a line of Bryan virus-transformed hamster cells, and two SRD-RSV transformed rat cell lines, LR3/1 and LR3/2. Cell...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.32.1.175-186.1979
更新日期:1979-10-01 00:00:00
abstract:UNLABELLED:Human metapneumovirus (hMPV) is a respiratory paramyxovirus that is distributed worldwide and induces significant airway morbidity. Despite the relevance of hMPV as a pathogen, many aspects of the immune response to this virus are still largely unknown. In this report, we focus on the antiviral immune respon...
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abstract::To assess the possible contribution of host immune responses to the exertion of Fv2-associated resistance to Friend virus (FV)-induced disease development, we inoculated C57BL/6 (B6) mice that lacked various subsets of lymphocytes with FV containing no lactate dehydrogenase-elevating virus. Fv2(r) B6 mice lacking CD4(...
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pub_type: 杂志文章
doi:10.1128/JVI.02506-13
更新日期:2013-12-01 00:00:00
abstract::Serial serum specimens from 22 herpes simplex virus (HSV)-seronegative recipients of an HSV type 2 (HSV-2) glycoprotein subunit vaccine were analyzed by radioimmunoprecipitation and polyacrylamide gel electrophoresis for the development of antibodies to HSV-2 gB, gD, and g80, a complex of gC and gE. Volunteers receive...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.56.2.475-481.1985
更新日期:1985-11-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.70.5.3032-3038.1996
更新日期:1996-05-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/jvi.76.23.11982-11988.2002
更新日期:2002-12-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.62.2.528-533.1988
更新日期:1988-02-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.69.10.6567-6571.1995
更新日期:1995-10-01 00:00:00
abstract::A conjugate of Pseudomonas exotoxin and epidermal growth factor (PE-EGF) inhibits proteins synthesis in KB cells, and this inhibition is increased by adenovirus. Protein synthesis inhibition is dependent on the amount of adenovirus and PE-EGF used and the time of incubation of cells with these agents. With 1 microgram...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.51.3.650-655.1984
更新日期:1984-09-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.00665-06
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.73.2.1350-1361.1999
更新日期:1999-02-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/JVI.66.2.886-893.1992
更新日期:1992-02-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.65.5.2408-2414.1991
更新日期:1991-05-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.54.1.58-64.1985
更新日期:1985-04-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.41.1.78-87.1982
更新日期:1982-01-01 00:00:00
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journal_title:Journal of virology
pub_type: 杂志文章
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更新日期:2012-11-01 00:00:00
abstract::Molecular clones of closed circular DNA molecules of a mink cell focus-inducing murine leukemia virus (MCF-13 MuLV) were generated. Closed circular DNA molecules isolated from a Hirt extraction of recently infected NIH/3T3 cells were inserted at their unique EcoRI site into lambda gtWES.lambda B. Restriction endonucle...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.43.1.348-351.1982
更新日期:1982-07-01 00:00:00
abstract::The pandemic threat posed by emerging zoonotic influenza A viruses necessitates development of antiviral agents effective against various antigenic subtypes. Human monoclonal antibody (hMAb) targeting the hemagglutinin (HA) stalk offers a promising approach to control influenza virus infections. Here, we investigated ...
journal_title:Journal of virology
pub_type: 杂志文章
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更新日期:2016-11-14 00:00:00
abstract::Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus and one of the most common agents of viral encephalitis. The infectious entry process of JEV into host cells remains largely unknown. Here, we present a systemic study concerning the cellular entry mechanism of JEV to B104 rat neuroblastoma cells. It was...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.00903-12
更新日期:2012-12-01 00:00:00
abstract::We have demonstrated that a liposomal array of well-ordered trimers enhances B cell activation, germinal center formation, and the elicitation of tier-2 autologous neutralizing antibodies. Previously, we coupled well-ordered cleavage-independent NFL trimers via their C-terminal polyhistidine tails to nickel lipids int...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.00443-17
更新日期:2017-07-27 00:00:00
abstract::Murine norovirus (MNV), a prevalent pathogen of laboratory mice, shares many characteristics with human noroviruses. Previous results indicated that passage of MNV1 in the macrophage cell line RAW 264.7 results in attenuation in STAT1-deficient mice (C. E. Wobus, S. M. Karst, L. B. Thackray, K. O. Chang, S. V. Sosnovt...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.00237-08
更新日期:2008-08-01 00:00:00
abstract::The level of RNase activity in human interferon preparations was examined. Although sequential purification of interferon resulted in nearly a 300-fold increase in specific activity, RNase-specific activity remained more or less constant. The implications of this finding for the analyses of the mode of action of inter...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.21.3.1247-1248.1977
更新日期:1977-03-01 00:00:00
abstract::A characterization of the antigenic determinants (epitopes) of the glycoprotein (G) of infectious hematopoietic necrosis virus was made by expressing different regions of the G gene in Escherichia coli. A cDNA copy of the G gene was divided into four fragments by TaqI digestion, and the fragments were subcloned into p...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.65.3.1611-1615.1991
更新日期:1991-03-01 00:00:00
abstract::The complete DNA sequence of bovine adenovirus type 3 is reported here. The size of the genome is 34,446 bp in length with a G+C content of 54%. All the genes of the early and late regions are present in the expected locations of the genome. However, the late-region genes are organized into seven families, instead of ...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.72.2.1394-1402.1998
更新日期:1998-02-01 00:00:00
abstract::The reticuloendotheliosis viruses (REVs), originally isolated from avian species, constitute a group of retroviruses which are more closely related to mammalian retroviruses than to other avian retroviruses. The envelope glycoproteins of members of the REV group display a striking amino acid sequence identity with a g...
journal_title:Journal of virology
pub_type: 杂志文章
doi:10.1128/JVI.66.6.3448-3454.1992
更新日期:1992-06-01 00:00:00