-
Viruses Feb 2021De novo viral protein synthesis following entry into host cells is essential for viral replication. As a consequence, viruses have evolved mechanisms to engage the host... (Review)
Review
De novo viral protein synthesis following entry into host cells is essential for viral replication. As a consequence, viruses have evolved mechanisms to engage the host translational machinery while at the same time avoiding or counteracting host defenses that act to repress translation. Mammalian orthoreoviruses are dsRNA-containing viruses whose mRNAs were used as models for early investigations into the mechanisms that underpin the recognition and engagement of eukaryotic mRNAs by host cell ribosomes. However, there remain many unanswered questions and paradoxes regarding translation of reoviral mRNAs in the context of infection. This review summarizes the current state of knowledge about reovirus translation, identifies key unanswered questions, and proposes possible pathways toward a better understanding of reovirus translation.
Topics: Animals; Host-Pathogen Interactions; Humans; Orthoreovirus, Mammalian; Protein Biosynthesis; RNA, Viral; Reoviridae Infections; Ribosomes; Viral Proteins; Virus Replication
PubMed: 33670092
DOI: 10.3390/v13020275 -
Journal of Virology Feb 2022Segmentation of viral genomes provides the potential for genetic exchange within coinfected cells. However, for this potential to be realized, coinfecting genomes must...
Segmentation of viral genomes provides the potential for genetic exchange within coinfected cells. However, for this potential to be realized, coinfecting genomes must mix during the viral life cycle. The efficiency of reassortment, in turn, dictates its potential to drive evolution. The opportunity for mixing within coinfected cells may vary greatly across virus families, such that the evolutionary implications of genome segmentation differ as a result of core features of the viral life cycle. To investigate the relationship between viral replication compartments and genetic exchange, we quantified reassortment in mammalian orthoreovirus (reovirus). Reoviruses carry a 10-segmented, double-stranded RNA genome, which is replicated within proteinaceous structures termed inclusion bodies. We hypothesized that inclusions impose a barrier to reassortment. We quantified reassortment between wild-type () and variant () reoviruses that differ by one nucleotide per segment. Studies of systems in both T1L and T3D backgrounds revealed frequent reassortment without bias toward particular genotypes. However, reassortment was more efficient in the T3D serotype. Since T1L and T3D viruses exhibit different inclusion body morphologies, we tested the impact of this phenotype on reassortment. In both serotypes, reassortment levels did not differ by inclusion morphology. Reasoning that the merging of viral inclusions may be critical for genome mixing, we then tested the effect of blocking merging. Reassortment proceeded efficiently even under these conditions. Our findings indicate that reovirus reassortment is highly efficient despite the localization of many viral processes to inclusion bodies, and that the robustness of this genetic exchange is independent of inclusion body structure and fusion. Quantification of reassortment in diverse viral systems is critical to elucidate the implications of genome segmentation for viral evolution. In principle, genome segmentation offers a facile means of genetic exchange between coinfecting viruses. In practice, there may be physical barriers within the cell that limit the mixing of viral genomes. Here, we tested the hypothesis that localization of the various stages of the mammalian orthoreovirus life cycle within cytoplasmic inclusion bodies compartmentalizes viral replication and limits genetic exchange. Contrary to this hypothesis, our data indicate that reovirus reassortment occurs readily within coinfected cells and is not strongly affected by the structure or dynamics of viral inclusion bodies. We conclude that the potential for reassortment to contribute to reovirus evolution is high.
Topics: Animals; Cell Line; Genome, Viral; Genotype; Inclusion Bodies, Viral; Mice; Microtubules; Orthoreovirus, Mammalian; Reassortant Viruses; Serogroup; Virus Replication
PubMed: 34935439
DOI: 10.1128/JVI.01832-21 -
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 -
Poultry Science Oct 2023Since 2005, novel duck reoviruses have been outbreaks in duck breeding areas such as central China and South China. In recent years, the incidence rate of this disease...
Since 2005, novel duck reoviruses have been outbreaks in duck breeding areas such as central China and South China. In recent years, the incidence rate of this disease is still increasing, bringing serious economic losses to waterfowl breeding industry. This study isolated 3 novel duck reoviruses (NDRV-SDLS, NDRV-SDWF, and NDRV-SDYC) from sick ducks in 3 local duck farms in Shandong Province. The study aimed to investigate the characteristics of these viruses. The virus is inoculated into duck embryo fibroblasts, where the virus replicates to produce syncytium and dies within 3 to 5 d. The viruses were also isolated from infected ducks, and RT-PCR amplified the whole genomes after passage purification in duck embryos. The resulting whole genome was analyzed for genetic evolution. The total length of the gene sequencing was 23,418 bp, divided into 10 fragments. Gene sequence comparison showed that the 3 strains had high similarity with novel duck reoviruses (NDRV) but low similarity with chicken-origin reovirus (chicken ARV) and Muscovy duck reovirus (MDRV), especially in the σC segment. Phylogenetic analysis of the 10 fragments showed that the 3 isolates constituted the same evolutionary clade as other DRV reference strains and were far related to ARV and MDRV in different evolutionary clades. The results of all 10 segments indicate that the isolates are in the evolutionary branch of NDRV, suggesting that the novel waterfowl reovirus is the dominant circulating strain in Shandong. This study complements the gene bank information of NDRV and provides references for vaccine research and disease prediction of NDRV in Shandong.
Topics: Animals; Orthoreovirus, Avian; Reoviridae Infections; Phylogeny; Chickens; China; Poultry Diseases
PubMed: 37566967
DOI: 10.1016/j.psj.2023.102969 -
PloS One 2013Family Reoviridae, subfamily Spinareovirinae, includes nine current genera. Two of these genera, Aquareovirus and Orthoreovirus, comprise members that are closely...
Family Reoviridae, subfamily Spinareovirinae, includes nine current genera. Two of these genera, Aquareovirus and Orthoreovirus, comprise members that are closely related and consistently share nine homologous proteins. Orthoreoviruses have 10 dsRNA genome segments and infect reptiles, birds, and mammals, whereas aquareoviruses have 11 dsRNA genome segments and infect fish. Recently, the first 10-segmented fish reovirus, piscine reovirus (PRV), has been identified and shown to be phylogenetically divergent from the 11-segmented viruses constituting genus Aquareovirus. We have recently extended results for PRV by showing that it does not encode a fusion-associated small transmembrane (FAST) protein, but does encode an outer-fiber protein containing a long N-terminal region of predicted α-helical coiled coil. Three recently characterized 11-segmented fish reoviruses, obtained from grass carp in China and sequenced in full, are also divergent from the viruses now constituting genus Aquareovirus, though not to the same extent as PRV. In the current study, we reexamined the sequences of these three recent isolates of grass carp reovirus (GCRV)-HZ08, GD108, and 104-for further clues to their evolution relative to other aqua- and orthoreoviruses. Structure-based fiber motifs in their encoded outer-fiber proteins were characterized, and other bioinformatics analyses provided evidence against the presence of a FAST protein among their encoded nonstructural proteins. Phylogenetic comparisons showed the combination of more distally branching, approved Aquareovirus and Orthoreovirus members, plus more basally branching isolates GCRV104, GCRV-HZ08/GD108, and PRV, constituting a larger, monophyletic taxon not suitably recognized by the current taxonomic hierarchy. Phylogenetics also suggested that the last common ancestor of all these viruses was a fiber-encoding, nonfusogenic virus and that the FAST protein family arose from at least two separate gain-of-function events. In addition, an apparent evolutionary correlation was found between the gain or loss of NS-FAST and outer-fiber proteins among more distally branching members of this taxon.
Topics: Amino Acid Sequence; Animals; Biological Evolution; Carps; Computational Biology; Fish Diseases; Genome, Viral; Molecular Sequence Data; Orthoreovirus; Phylogeny; Protein Structure, Secondary; RNA, Double-Stranded; RNA, Viral; Reoviridae; Sequence Alignment; Sequence Homology, Amino Acid; Viral Nonstructural Proteins
PubMed: 23861926
DOI: 10.1371/journal.pone.0068607 -
Clinical Infectious Diseases : An... Mar 2007The role that bats have played in the emergence of several new infectious diseases has been under review. Bats have been identified as the reservoir hosts of newly... (Review)
Review
The role that bats have played in the emergence of several new infectious diseases has been under review. Bats have been identified as the reservoir hosts of newly emergent viruses such as Nipah virus, Hendra virus, and severe acute respiratory syndrome-like coronaviruses. This article expands on recent findings about bats and viruses and their relevance to human infections. It briefly reviews the history of chiropteran viruses and discusses their emergence in the context of geography, phylogeny, and ecology. The public health and trade impacts of several outbreaks are also discussed. Finally, we attempt to predict where, when, and why we may see the emergence of new chiropteran viruses.
Topics: Animals; Chiroptera; Communicable Diseases, Emerging; Disease Outbreaks; Disease Vectors; Humans; Orthoreovirus, Mammalian; Phylogeny; Virus Diseases; Viruses
PubMed: 17278066
DOI: 10.1086/511078 -
Scientific Reports Jun 2019This study focuses on virus isolation of avian reoviruses from a tenosynovitis outbreak between September 2015 and June 2018, the molecular characterization of selected...
This study focuses on virus isolation of avian reoviruses from a tenosynovitis outbreak between September 2015 and June 2018, the molecular characterization of selected isolates based on partial S1 gene sequences, and the full genome characterization of seven isolates. A total of 265 reoviruses were detected and isolated, 83.3% from tendons and joints, 12.3% from the heart and 3.7% from intestines. Eighty five out of the 150 (56.6%) selected viruses for sequencing and characterization were successfully detected, amplified and sequenced. The characterized reoviruses grouped in six distinct genotypic clusters (GC1 to GC6). The most represented clusters were GC1 (51.8%) and GC6 (24.7%), followed by GC2 (12.9%) and GC4 (7.2%), and less frequent GC5 (2.4%) and GC3 (1.2%). A shift on cluster representation throughout time occurred. A reduction of GC1 and an increase of GC6 classified strains was noticed. The highest homologies to S1133 reovirus strain were detected in GC1 (~77%) while GC2 to GC6 homologies ranged between 58.5 and 54.1%. Over time these homologies have been maintained. Seven selected isolates were full genome sequenced. Results indicated that the L3, S1 and M2 genes, coding for proteins located in the virus capsid accounted for most of the variability of these viruses. The information generated in the present study helps the understanding of the epidemiology of reoviruses in California. In addition, provides insights on how other genes that are not commonly studied add variability to the reovirus genome.
Topics: Animals; California; Chickens; Communicable Diseases, Emerging; Genes, Viral; Genetic Variation; Genome, Viral; Genotype; Orthoreovirus, Avian; Phylogeny; Poultry Diseases; Public Health Surveillance; Reoviridae Infections; Sequence Analysis, DNA
PubMed: 31249323
DOI: 10.1038/s41598-019-45494-4 -
Virology Dec 2020Mammalian orthoreovirus (MRV) infections are ubiquitous in mammals. Increasing evidence suggests that some MRVs can cause severe respiratory disease and encephalitis in...
Mammalian orthoreovirus (MRV) infections are ubiquitous in mammals. Increasing evidence suggests that some MRVs can cause severe respiratory disease and encephalitis in humans and other animals. Previously, we isolated six bat MRV strains. However, the pathogenicity of these bat viruses remains unclear. In this study, we investigated the host range and pathogenicity of 3 bat MRV strains (WIV2, 3 and 7) which represent three serotypes. Our results showed that all of them can infect cell lines from different mammalian species and displayed different replication efficiency. The BALB/c mice infected by bat MRVs showed clinical symptoms with systematic infection especially in lung and intestines. Obvious tissue damage were found in all infected lungs. One of the strains, WIV7, showed higher replication efficiency in vitro and vivo and more severe pathogenesis in mice. Our results provide new evidence showing potential pathogenicity of bat MRVs in animals and probable risk in humans.
Topics: Animals; Cell Line; Chiroptera; Female; Host Specificity; Humans; Intestines; Lung; Mice; Mice, Inbred BALB C; Orthoreovirus, Mammalian; Pneumonia, Viral; Reoviridae Infections; Serogroup
PubMed: 32859395
DOI: 10.1016/j.virol.2020.05.014 -
Viruses May 2022Aquareovirus, which is a member of the Reoviridae family, was isolated from aquatic animals. A close molecular evolutionary relationship between aquareoviruses and...
Aquareovirus, which is a member of the Reoviridae family, was isolated from aquatic animals. A close molecular evolutionary relationship between aquareoviruses and mammalian orthoreoviruses was revealed. However, the functions of the aquareovirus genome-encoded proteins are poorly understood. We investigated the molecular characteristics of the outer capsid proteins, namely, VP5 and VP7, of grass carp reovirus (GCRV). The peptides VP5 and VP7 were determined using in-gel tryptic digestion and mass spectrometry. Recovered peptides represented 76% and 66% of the full-length VP5 and VP7 sequences, respectively. Significantly, two-lysine acetylation, as well as two-serine and two-threonine phosphorylation modifications, were first revealed in VP5. We found that the initial amino acid in VP5 was Pro43, suggesting that a lower amount of VP5 remained uncleaved in virions at the autocleavage site (Asn42-Pro43). Further biochemical evidence showed that the cleaved VP5N/VP5C conformation was the major constituent of the particles. Moreover, early cleavage fragments of VP7 and enhanced infectivity were detected after limited tryptic digestion of GCRV, indicating that stepwise VP7 cleavage is essential for VP5 conformational rearrangement. Our results provide insights into the roles of posttranslational modifications in VP5 and its association with VP7 in the viral life cycle.
Topics: Animals; Antibodies, Viral; Capsid Proteins; Carps; Mammals; Orthoreovirus; Reoviridae; Virion
PubMed: 35632773
DOI: 10.3390/v14051032 -
Journal of Virological Methods Jun 2020Reassortment of segmented viruses can be an important source of genetic diversity underlying viral evolution and emergence. Methods for the quantification of...
Reassortment of segmented viruses can be an important source of genetic diversity underlying viral evolution and emergence. Methods for the quantification of reassortment have been described but are often cumbersome and best suited for the analysis of reassortment between highly divergent parental strains. While it is useful to understand the potential of divergent parents to reassort, outcomes of such heterologous reassortment are driven by differential selection acting on the progeny and are typically strain specific. To quantify reassortment robustly, a system free of differential selection is needed. We have generated such a system for influenza A virus and for mammalian orthoreovirus by constructing well-matched parental viruses carrying small genetic tags. The method utilizes high-resolution melt technology for the identification of reassortant viruses. Ease of sample preparation and data analysis enables streamlined genotyping of a large number of virus clones. The method described here thereby allows quantification of the efficiency of reassortment and can be applied to diverse segmented viruses.
Topics: Animals; Cell Line; Flow Cytometry; Genetic Markers; Genetic Variation; Genome, Viral; Genotype; High-Throughput Nucleotide Sequencing; Humans; Influenza A virus; Mutation; Orthoreovirus, Mammalian; Reassortant Viruses; Recombination, Genetic; Sequence Analysis, RNA
PubMed: 32353455
DOI: 10.1016/j.jviromet.2020.113878