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Uirusu 2014Members of the genus Orthoreovirus in the family Reoviridae are nonenveloped, icosahedral viruses. Their genomes contain 10 segments of double-stranded RNA (dsRNA). The... (Review)
Review
Members of the genus Orthoreovirus in the family Reoviridae are nonenveloped, icosahedral viruses. Their genomes contain 10 segments of double-stranded RNA (dsRNA). The orthoreoviruses are divided into two subgroups, the fusogenic and nonfusogenic reoviruses, based on the ability of the virus to induce cell-to-cell fusion. The fusogenic subgroup consists of the avian reovirus, baboon reovirus, pteropine reovirus, and reptilian reovirus, whereas the nonfusogenic subgroup consists of the prototypical mammalian reovirus (MRV) species. MRVs are highly tractable experimental models for studies of segmented dsRNA virus replication and pathogenesis. Moreover, MRVs can selectively kill tumor cells and have been evaluated as oncolytic agents in clinical trials. This review provides a brief overview of current knowledge on the virological features of MRVs.
Topics: Animals; Cancer Vaccines; Chiroptera; Genes, Viral; Genetic Vectors; Genome, Viral; Humans; Life Cycle Stages; Neoplasms; Orthoreovirus; Orthoreovirus, Mammalian; RNA, Double-Stranded; Reverse Genetics; Virus Assembly; Virus Replication
PubMed: 26437841
DOI: 10.2222/jsv.64.191 -
Virology Oct 2022Nelson Bay orthoreovirus (NBV) is an emerging bat-borne virus and causes respiratory tract infections in humans sporadically. Over the last two decades, several strains...
Nelson Bay orthoreovirus (NBV) is an emerging bat-borne virus and causes respiratory tract infections in humans sporadically. Over the last two decades, several strains genetically related to NBV were isolated from humans and various bat species, predominantly in Southeast Asia (SEA), suggesting a high prevalence of the NBV species in this region. In this study, an orthoreovirus (ORV) belonging to the NBV species was isolated from Indonesian fruit bats' feces, tentatively named Paguyaman orthoreovirus (PgORV). Serological studies revealed that 81.2% (108/133) of Indonesian fruit bats sera had neutralizing antibodies against PgORV. Whole-genome sequencing and phylogenetic analysis of PgORV suggested the occurrence of past reassortments with other NBV strains isolated in SEA, indicating the dispersal and circulation of NBV species among bats in this region. Intranasal PgORV inoculation of laboratory mice caused severe pneumonia. Our study characterized PgORV's unique genetic background and highlighted the potential risk of PgORV-related diseases in Indonesia.
Topics: Animals; Antibodies, Neutralizing; Chiroptera; Humans; Indonesia; Mice; Orthoreovirus; Phylogeny
PubMed: 35987079
DOI: 10.1016/j.virol.2022.08.003 -
Proceedings of the National Academy of... May 2023Mammalian orthoreoviruses (reoviruses) serve as potential triggers of celiac disease and have oncolytic properties, making these viruses potential cancer therapeutics....
Mammalian orthoreoviruses (reoviruses) serve as potential triggers of celiac disease and have oncolytic properties, making these viruses potential cancer therapeutics. Primary attachment of reovirus to host cells is mainly mediated by the trimeric viral protein, σ1, which engages cell-surface glycans, followed by high-affinity binding to junctional adhesion molecule-A (JAM-A). This multistep process is thought to be accompanied by major conformational changes in σ1, but direct evidence is lacking. By combining biophysical, molecular, and simulation approaches, we define how viral capsid protein mechanics influence virus-binding capacity and infectivity. Single-virus force spectroscopy experiments corroborated by in silico simulations show that GM2 increases the affinity of σ1 for JAM-A by providing a more stable contact interface. We demonstrate that conformational changes in σ1 that lead to an extended rigid conformation also significantly increase avidity for JAM-A. Although its associated lower flexibility impairs multivalent cell attachment, our findings suggest that diminished σ1 flexibility enhances infectivity, indicating that fine-tuning of σ1 conformational changes is required to successfully initiate infection. Understanding properties underlying the nanomechanics of viral attachment proteins offers perspectives in the development of antiviral drugs and improved oncolytic vectors.
Topics: Animals; Capsid Proteins; Reoviridae; Orthoreovirus; Viral Proteins; Virus Attachment; Antibodies, Viral; Mammals
PubMed: 37186838
DOI: 10.1073/pnas.2220741120 -
Frontiers in Immunology 2018Salmonid red blood cells are the main target cells for (PRV). Three genotypes of PRV (PRV-1,2,3) infect Atlantic salmon (), Chinook salmon (), Coho salmon (), rainbow... (Review)
Review
Salmonid red blood cells are the main target cells for (PRV). Three genotypes of PRV (PRV-1,2,3) infect Atlantic salmon (), Chinook salmon (), Coho salmon (), rainbow trout () and brown trout (Salmo trutta), and can cause diseases like heart and skeletal muscle inflammation (HSMI), jaundice syndrome, erythrocyte inclusion body syndrome (EIBS) and proliferative darkening syndrome (PDS). Purified PRV administrated to fish has proven the causality for HSMI and EIBS. During the early peak phase of infection, salmonid erythrocytes are the main virus-replicating cells. In this initial phase, cytoplasmic inclusions called "virus factories" can be observed in the erythrocytes, and are the primary sites for the formation of new virus particles. The PRV-infected erythrocytes in Atlantic salmon mount a strong long-lasting innate antiviral response lasting for many weeks after the onset of infection. The antiviral response of Atlantic salmon erythrocytes involves upregulation of potential inhibitors of translation. In accordance with this, PRV-1 protein production in erythrocytes halts while virus RNA can persist for months. Furthermore, PRV infection in Coho salmon and rainbow trout are associated with anemia, and in Atlantic salmon lower hemoglobin levels are observed. Here we summarize and discuss the recently published findings on PRV infection, replication and effects on salmonid erythrocytes, and discuss how PRV can be a useful tool for the study of innate immune responses in erythrocytes, and help reveal novel immune functions of the red blood cells in fish.
Topics: Animals; Erythrocytes; Fish Diseases; Gene Expression Regulation; Host-Pathogen Interactions; Orthoreovirus; Reoviridae Infections; Salmo salar
PubMed: 30700987
DOI: 10.3389/fimmu.2018.03182 -
Viruses Jun 2020The family is the only non-enveloped virus family with members that use syncytium formation to promote cell-cell virus transmission. Syncytiogenesis is mediated by a...
The family is the only non-enveloped virus family with members that use syncytium formation to promote cell-cell virus transmission. Syncytiogenesis is mediated by a fusion-associated small transmembrane (FAST) protein, a novel family of viral membrane fusion proteins. Previous evidence suggested the fusogenic reoviruses arose from an ancestral non-fusogenic virus, with the preponderance of fusogenic species suggesting positive evolutionary pressure to acquire and maintain the fusion phenotype. New phylogenetic analyses that included the atypical waterfowl subgroup of avian reoviruses and recently identified new orthoreovirus species indicate a more complex relationship between reovirus speciation and fusogenic capacity, with numerous predicted internal indels and 5'-terminal extensions driving the evolution of the orthoreovirus' polycistronic genome segments and their encoded FAST and fiber proteins. These inferred recombination events generated bi- and tricistronic genome segments with diverse gene constellations, they occurred pre- and post-orthoreovirus speciation, and they directly contributed to the evolution of the four extant orthoreovirus FAST proteins by driving both the gain and loss of fusion capability. We further show that two distinct post-speciation genetic events led to the loss of fusion in the waterfowl isolates of avian reovirus, a recombination event that replaced the p10 FAST protein with a heterologous, non-fusogenic protein and point substitutions in a conserved motif that destroyed the p10 assembly into multimeric fusion platforms.
Topics: Amino Acid Sequence; Animals; Animals, Wild; Anseriformes; Bird Diseases; Evolution, Molecular; Gain of Function Mutation; Genetic Speciation; Genome, Viral; Giant Cells; Orthoreovirus; Phylogeny; Reoviridae Infections; Sequence Alignment; Viral Fusion Proteins
PubMed: 32610593
DOI: 10.3390/v12070702 -
Viruses Aug 2022(MRVs) are increasingly reported to cause various diseases in humans and other animals, with many possibly originating from bats, highlighting the urgent need to...
(MRVs) are increasingly reported to cause various diseases in humans and other animals, with many possibly originating from bats, highlighting the urgent need to investigate the diversity of bat-borne MRVs (BtMRVs). Here, we report the detection and characterization of a reassortant MRV that was isolated from a bat colony in Xinjiang, China. The BtMRV showed a wide host and organ tropism and can efficiently propagate the cell lines of different animals. It caused mild damage in the lungs of the experimentally inoculated suckling mice and was able to replicate in multiple organs for up to three weeks post-inoculation. Complete genome analyses showed that the virus was closely related to MRVs in a wide range of animals. An intricate reassortment network was revealed between the BtMRV and MRVs of human, deer, cattle, civet and other bat species. Specifically, we found a bat-specific clade of segment M1 that provides a gene source for the reassortment of human MRVs. These data provide important insights to understand the diversity of MRVs and their natural circulation between bats, humans, and other animals. Further investigation and surveillance of MRV in bats and other animals are needed to control and prevent potential MRV-related diseases.
Topics: Animals; Cattle; China; Chiroptera; Deer; Humans; Mice; Orthoreovirus; Orthoreovirus, Mammalian; Phylogeny; Sequence Analysis, DNA
PubMed: 36146702
DOI: 10.3390/v14091897 -
Science China. Life Sciences Feb 2015Over the last 30 years, aquaculture has become the fastest growing form of agriculture production in the world, but its development has been hampered by a diverse range... (Review)
Review
Over the last 30 years, aquaculture has become the fastest growing form of agriculture production in the world, but its development has been hampered by a diverse range of pathogenic viruses. During the last decade, a large number of viruses from aquatic animals have been identified, and more than 100 viral genomes have been sequenced and genetically characterized. These advances are leading to better understanding about antiviral mechanisms and the types of interaction occurring between aquatic viruses and their hosts. Here, based on our research experience of more than 20 years, we review the wealth of genetic and genomic information from studies on a diverse range of aquatic viruses, including iridoviruses, herpesviruses, reoviruses, and rhabdoviruses, and outline some major advances in our understanding of virus-host interactions in animals used in aquaculture.
Topics: Animals; Aquaculture; Fish Diseases; Fishes; Genome, Viral; Genomics; Herpesviridae; Iridovirus; Orthoreovirus; Rhabdoviridae
PubMed: 25591452
DOI: 10.1007/s11427-015-4802-y -
Nature Communications May 2023Mammalian orthoreovirus (reovirus) infects most mammals and is associated with celiac disease in humans. In mice, reovirus infects the intestine and disseminates...
Mammalian orthoreovirus (reovirus) infects most mammals and is associated with celiac disease in humans. In mice, reovirus infects the intestine and disseminates systemically to cause serotype-specific patterns of disease in the brain. To identify receptors conferring reovirus serotype-dependent neuropathogenesis, we conducted a genome-wide CRISPRa screen and identified paired immunoglobulin-like receptor B (PirB) as a receptor candidate. Ectopic expression of PirB allowed reovirus binding and infection. PirB extracelluar D3D4 region is required for reovirus attachment and infectivity. Reovirus binds to PirB with nM affinity as determined by single molecule force spectroscopy. Efficient reovirus endocytosis requires PirB signaling motifs. In inoculated mice, PirB is required for maximal replication in the brain and full neuropathogenicity of neurotropic serotype 3 (T3) reovirus. In primary cortical neurons, PirB expression contributes to T3 reovirus infectivity. Thus, PirB is an entry receptor for reovirus and contributes to T3 reovirus replication and pathogenesis in the murine brain.
Topics: Animals; Humans; Mice; Antibodies, Viral; Orthoreovirus, Mammalian; Receptors, Immunologic; Reoviridae Infections; Receptors, Virus
PubMed: 37147336
DOI: 10.1038/s41467-023-38327-6 -
Food and Environmental Virology Sep 2016The genus Orthoreovirus contains nonenveloped viruses with double-stranded gene segments encased in a double-layered icosahedral capsid shell. These features constitute... (Review)
Review
The genus Orthoreovirus contains nonenveloped viruses with double-stranded gene segments encased in a double-layered icosahedral capsid shell. These features constitute major determinants of virion stability in the environment and virion resistance against physical and chemical agents. Reovirus (ReoV) is the general term most commonly used for all virus strains that infect humans and nonhuman animals. Several studies have demonstrated the frequent occurrence of ReoV in wastewaters and natural waters, including surface and ground waters from different geographical areas. Most of these studies have reported higher concentrations of ReoV than any other enteric virus analyzed. They are more commonly isolated in chlorine-disinfected wastewaters than other enteric viruses, and appear to survive longer in water. The ability of ReoV to form large aggregates, even with different types of enteric viruses (e.g., poliovirus) and their ability to undergo mechanisms of gene segment reassortment among different serotypes may also explain their greater stability. Different approaches have been applied for concentration of ReoV from water; however, the recovery efficiency of the filtration methods has not been fully evaluated. Recently, molecular methods for identification of ReoV strains and quantification of virus genome have been developed. Studies have shown that the overall detection sensitivity of ReoV RNA is enhanced through initial replication of infectious virions in cell culture. More studies are needed to specifically address unresolved issues about the fate and distribution of ReoV in the environment since this virus is not commonly included in virological investigations.
Topics: Disinfectants; Fresh Water; Orthoreovirus; Wastewater
PubMed: 27318494
DOI: 10.1007/s12560-016-9250-8 -
BMC Veterinary Research Aug 2022Piscine orthoreovirus genotype-1 (PRV-1) is a virus commonly associated with Atlantic salmon aquaculture with global variability in prevalence and association with...
Piscine orthoreovirus genotype-1 (PRV-1) is a virus commonly associated with Atlantic salmon aquaculture with global variability in prevalence and association with disease. From August 2016 to November 2019, 2,070 fish sampled at 64 Atlantic salmon net-pen farm sites during 302 sampling events from British Columbia, Canada, were screened for PRV-1 using real-time qPCR. Nearly all populations became PRV-1 positive within one year of seawater entry irrespective of location, time of stocking, or producer. Cohorts became infected between 100-300 days at sea in > 90% of repeatedly sampled sites and remained infected until harvest (typically 500-700 days at sea). Heart inflammation, which is sometimes attributed to PRV-1, was also assessed in 779 production mortalities from 47 cohorts with known PRV status. Mild heart inflammation was common in mortalities from both PRV + and PRV- populations (67% and 68% prevalence, respectively). Moderate and severe lymphoplasmacytic heart inflammation was rare (11% and 3% prevalence, respectively); however, mainly arose (66 of 77 occurrences) in populations with PRV-1. Detection of PRV-1 RNA was also accomplished in water and sediment for which methods are described. These data cumulatively identify that PRV-1 ubiquitously infects farmed Atlantic salmon in British Columbia during seawater production but only in rare instances correlates with heart inflammation.
Topics: Animals; Arrhythmias, Cardiac; Canada; Fish Diseases; Genotype; Inflammation; Orthoreovirus; Reoviridae Infections; Salmo salar
PubMed: 35948980
DOI: 10.1186/s12917-022-03409-y