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1.
Sci Rep ; 14(1): 17914, 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39095425

RÉSUMÉ

The rhizome concept proposed by Gilles Deleuze and Félix Guattari offers a novel perspective on the organization and interdependence of complex constellations of heterogeneous entities, their mapping and their ruptures. The emphasis of the present study is placed on the dynamics of contacts and communication among such entities that arise from experimentation, without any favored hierarchy or origin. When applied to biological evolution, the rhizome concept integrates all types of heterogeneity resulting from "symbiotic" relationships among living beings (or their genomic material), horizontal genetic transfer, recombination and mutation, and breaks away from the approach that gives rise to the phylogenetic tree of life. It has already been applied to describe the dynamics and evolution of RNA viruses. Thus, here we introduce a novel framework for the interpretation the viral quasispecies concept, which explains the evolution of RNA virus populations as the result of dynamic interconnections and multifaceted interdependence between highly heterogeneous viral sequences and its inherently heterogeneous host cells. The rhizome network perspective underlines even further the medical implications of the broad mutant spectra of viruses that are in constant flow, given the multiple pathways they have available for fitness loss and gain.


Sujet(s)
Évolution moléculaire , Phylogenèse , Quasi-espèce , Rhizome , Rhizome/virologie , Quasi-espèce/génétique , Virus à ARN/génétique , Virus à ARN/classification , Transfert horizontal de gène , Mutation , Génome viral
2.
Sci Rep ; 14(1): 16747, 2024 Jul 20.
Article de Anglais | MEDLINE | ID: mdl-39033233

RÉSUMÉ

In Argentina, migratory activity in search of floral diversity has become a common approach to maximizing honey production. The Entre Ríos province possesses a floral diversity that allows beekeepers to perform migratory or stationary management. Beyond the impact caused by transhumance, migratory colonies in this province start and end the season in monoculture areas. To study the effect of these practices on viral infection, we assayed for the presence, abundance and genetic characterization of the Deformed Wing Virus (DWV) in honey bees from apiaries with both types of management. In migratory apiaries, DWV was detectable in 86.2% of the colonies at the beginning of the season (September 2018), and 66% at the end of the season (March 2019). On the other hand, DWV was detected in 44.11% and 53.12% of stationary samples, at the beginning and the end of the season, respectively. Sequence analysis from migratory and stationary colonies revealed that all samples belonged to DWV-A type. The highest viral loads were detected in migratory samples collected in September. Higher DWV presence and abundance were associated with migratory management and the sampling time. Based on our findings we propose that the benefit of migration to wild flowering areas can be dissipated when the bee colonies end the season with monoculture.


Sujet(s)
Virus à ARN , Animaux , Abeilles/virologie , Argentine , Virus à ARN/génétique , Virus à ARN/isolement et purification , Migration animale , Saisons , Phylogenèse , Apiculture , Charge virale
3.
Arch Virol ; 169(8): 161, 2024 Jul 09.
Article de Anglais | MEDLINE | ID: mdl-38981885

RÉSUMÉ

Here, we report a novel ourmia-like mycovirus, named "Phomopsis asparagi magoulivirus 1" (PaMV1), derived from the phytopathogenic fungus Phomopsis asparagi. The genome of PaMV1 consists of a positive-sense single-stranded RNA (+ ssRNA) that is 2,639 nucleotides in length, with a GC content of 57.13%. It contains a single open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) consisting of 686 amino acids with a molecular mass of 78.57 kDa. Phylogenetic analysis based on RdRp sequences revealed that PaMV1 grouped together with Diaporthe gulyae magoulivirus 1 (DgMV1) in a distinct clade. Sequence comparisons and phylogenetic analysis suggest that PaMV1 is a novel member of the genus Magoulivirus, family Botourmiaviridae.


Sujet(s)
Virus fongiques , Génome viral , Cadres ouverts de lecture , Phomopsis (genre) , Phylogenèse , ARN viral , Virus fongiques/génétique , Virus fongiques/classification , Virus fongiques/isolement et purification , Phomopsis (genre)/virologie , ARN viral/génétique , Séquençage du génome entier , RNA replicase/génétique , Composition en bases nucléiques , Maladies des plantes/microbiologie , Maladies des plantes/virologie , Protéines virales/génétique , Séquence nucléotidique , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification
4.
Arch Virol ; 169(8): 165, 2024 Jul 11.
Article de Anglais | MEDLINE | ID: mdl-38990253

RÉSUMÉ

Monilinia fructicola is one of the most devastating fungal diseases of rosaceous fruit crops, both in the field and postharvest, causing significant yield losses. Here, we report the discovery of a novel positive single-stranded RNA virus, Monilinia fructicola hypovirus 3 (MfHV3), in a strain (hf-1) of the phytopathogenic fungus Monilinia fructicola. The complete genome of MfHV3 is 9259 nucleotides (nt) in length and contains a single large open reading frame (ORF) from nt position 462 to 8411. This ORF encodes a polyprotein with three conserved domains, namely UDP-glycosyltransferase, RNA-dependent RNA polymerase (RdRp), and DEAD-like helicase. The MfHV3 polyprotein shares the highest similarity with Colletotrichum camelliae hypovirus 1. Phylogenetic analysis indicated that MfHV3 clustered with members of the genus Betahypovirus within the family Hypoviridae. Taken together, the results of genomic organization comparisons, amino acid sequence alignments, and phylogenetic analysis convincingly show that MfHV3 is a new member of the genus Betahypovirus, family Hypoviridae.


Sujet(s)
Ascomycota , Virus fongiques , Génome viral , Cadres ouverts de lecture , Phylogenèse , Maladies des plantes , Ascomycota/virologie , Ascomycota/génétique , Virus fongiques/génétique , Virus fongiques/classification , Virus fongiques/isolement et purification , Maladies des plantes/microbiologie , Maladies des plantes/virologie , ARN viral/génétique , Protéines virales/génétique , Séquençage du génome entier , Virus à ARN/génétique , Virus à ARN/classification , Virus à ARN/isolement et purification , RNA replicase/génétique , Séquence d'acides aminés
5.
Microb Genom ; 10(7)2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39037207

RÉSUMÉ

The insect order Blattodea (cockroaches and termites) has drawn substantial research attention for their dietary habits and lifestyle of living with or around humans. In the present study, we focused on the discovery of RNA viruses hidden in Blattodea insects using the publicly available RNA sequencing datasets. Overall, 136 distinctive RNA viruses were identified from 36 Blattodea species, of which more than 70 % were most closely related to the invertebrate-associated viral groups within Picornavirales, Sobelivirales, Bunyaviricetes, Jingchuvirales, Durnavirales, Lispiviridae, Orthomyxoviridae, Permutotetraviridae, Flaviviridae and Muvirales. Several viruses were associated with pathogens of vertebrates (Paramyxoviridae), plants (Tymovirales), protozoa (Totiviridae), fungi (Narnaviridae) and bacteria (Norzivirales). Collectively, 93 complete or near-complete viral genomes were retrieved from the datasets, and several viruses appeared to have remarkable temporal and spatial distributions. Interestingly, the newly identified Periplaneta americana dicistrovirus displayed a remarkable distinct bicistronic genome arrangement from the well-recognized dicistroviruses with the translocated structural and non-structural polyprotein encoding open reading frames over the genome. These results significantly enhance our knowledge of RNA virosphere in Blattodea insects, and the novel genome architectures in dicistroviruses and other RNA viruses may break our stereotypes in the understanding of the genomic evolution and the emergence of potential novel viral species.


Sujet(s)
Blattes , Génome viral , Isoptera , Phylogenèse , Virus à ARN , Animaux , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , Isoptera/virologie , Blattes/virologie , Virus des insectes/génétique , Virus des insectes/classification , Virus des insectes/isolement et purification
6.
Arch Virol ; 169(8): 166, 2024 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-38995418

RÉSUMÉ

The virus family Phenuiviridae (order Hareavirales, comprising segmented negative-sense single stranded RNA viruses) has highly diverse members that are known to infect animals, plants, protozoans, and fungi. In this study, we identified a novel phenuivirus infecting a strain of the entomopathogenic fungus Cordyceps javanica isolated from a small brown plant hopper (Laodelphax striatellus), and this virus was tentatively named "Cordyceps javanica negative-strand RNA virus 1" (CjNRSV1). The CjNRSV1 genome consists of three negative-sense single stranded RNA segments (RNA1-3) with lengths of 7252, 2401, and 1117 nt, respectively. The 3'- and 5'-terminal regions of the RNA1, 2, and 3 segments have identical sequences, and the termini of the RNA segments are complementary to each other, reflecting a common characteristic of viruses in the order Hareavirales. RNA1 encodes a large protein (∼274 kDa) containing a conserved domain for the bunyavirus RNA-dependent RNA polymerase (RdRP) superfamily, with 57-80% identity to the RdRP encoded by phenuiviruses in the genus Laulavirus. RNA2 encodes a protein (∼79 kDa) showing sequence similarity (47-63% identity) to the movement protein (MP, a plant viral cell-to-cell movement protein)-like protein (MP-L) encoded by RNA2 of laulaviruses. RNA3 encodes a protein (∼28 kDa) with a conserved domain of the phenuivirid nucleocapsid protein superfamily. Phylogenetic analysis using the RdRPs of various phenuiviruses and other unclassified phenuiviruses showed CjNRSV1 to be grouped with established members of the genus Laulavirus. Our results suggest that CjNRSV1 is a novel fungus-infecting member of the genus Laulavirus in the family Phenuiviridae.


Sujet(s)
Cordyceps , Génome viral , Phylogenèse , ARN viral , Cordyceps/génétique , ARN viral/génétique , Virus fongiques/classification , Virus fongiques/génétique , Virus fongiques/isolement et purification , Protéines virales/génétique , Virus à ARN de polarité négative/génétique , Virus à ARN de polarité négative/classification , RNA replicase/génétique , Virus à ARN/génétique , Virus à ARN/classification , Virus à ARN/isolement et purification , Séquence d'acides aminés , Cadres ouverts de lecture
7.
Arch Virol ; 169(8): 159, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38972922

RÉSUMÉ

In this study, we identified a novel partitivirus, named "Cordyceps militaris partitivirus 1" (CmPV1), in Cordyceps militaris strain RCEF7506. The complete genome of CmPV1 comprises two segments, dsRNA1 and dsRNA2, each encoding a single protein. dsRNA1 (2,206 bp) encodes an RNA-dependent RNA polymerase (RdRp), and dsRNA2 (2,256 bp) encodes a coat protein (CP). Sequence analysis revealed that dsRNA1 has the highest similarity to that of Bipolaris maydis partitivirus 2 (BmPV2), whereas dsRNA2 shows the highest similarity to human blood-associated partitivirus (HuBPV). Phylogenetic analysis based on RdRp sequences suggests that CmPV1 is a new member of the genus Betapartitivirus of the family Partitiviridae. This is the first documentation of a betapartitivirus infecting the entomopathogenic fungus C. militaris.


Sujet(s)
Cordyceps , Virus fongiques , Génome viral , Phylogenèse , Virus à ARN , Cordyceps/génétique , Cordyceps/virologie , Cordyceps/isolement et purification , Génome viral/génétique , Virus fongiques/génétique , Virus fongiques/isolement et purification , Virus fongiques/classification , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , ARN viral/génétique , RNA replicase/génétique , Cadres ouverts de lecture , Protéines virales/génétique , Protéines de capside/génétique
8.
PLoS Pathog ; 20(7): e1012337, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38959190

RÉSUMÉ

The worldwide dispersal of the ectoparasitic mite Varroa destructor from its Asian origins has fundamentally transformed the relationship of the honey bee (Apis mellifera) with several of its viruses, via changes in transmission and/or host immunosuppression. The extent to which honey bee-virus relationships change after Varroa invasion is poorly understood for most viruses, in part because there are few places in the world with several geographically close but completely isolated honey bee populations that either have, or have not, been exposed long-term to Varroa, allowing for separate ecological, epidemiological, and adaptive relationships to develop between honey bees and their viruses, in relation to the mite's presence or absence. The Azores is one such place, as it contains islands with and without the mite. Here, we combined qPCR with meta-amplicon deep sequencing to uncover the relationship between Varroa presence, and the prevalence, load, diversity, and phylogeographic structure of eight honey bee viruses screened across the archipelago. Four viruses were not detected on any island (ABPV-Acute bee paralysis virus, KBV-Kashmir bee virus, IAPV-Israeli acute bee paralysis virus, BeeMLV-Bee macula-like virus); one (SBV-Sacbrood virus) was detected only on mite-infested islands; one (CBPV-Chronic bee paralysis virus) occurred on some islands, and two (BQCV-Black queen cell virus, LSV-Lake Sinai virus,) were present on every single island. This multi-virus screening builds upon a parallel survey of Deformed wing virus (DWV) strains that uncovered a remarkably heterogeneous viral landscape featuring Varroa-infested islands dominated by DWV-A and -B, Varroa-free islands naïve to DWV, and a refuge of the rare DWV-C dominating the easternmost Varroa-free islands. While all four detected viruses investigated here were affected by Varroa for one or two parameters (usually prevalence and/or the Richness component of ASV diversity), the strongest effect was observed for the multi-strain LSV. Varroa unambiguously led to elevated prevalence, load, and diversity (Richness and Shannon Index) of LSV, with these results largely shaped by LSV-2, a major LSV strain. Unprecedented insights into the mite-virus relationship were further gained from implementing a phylogeographic approach. In addition to enabling the identification of a novel LSV strain that dominated the unique viral landscape of the easternmost islands, this approach, in combination with the recovered diversity patterns, strongly suggests that Varroa is driving the evolutionary change of LSV in the Azores. This study greatly advances the current understanding of the effect of Varroa on the epidemiology and adaptive evolution of these less-studied viruses, whose relationship with Varroa has thus far been poorly defined.


Sujet(s)
Varroidae , Animaux , Abeilles/virologie , Abeilles/parasitologie , Varroidae/virologie , Açores , Virus des insectes/génétique , Virus des insectes/isolement et purification , Virus des insectes/classification , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification
9.
Microbiology (Reading) ; 170(7)2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39046321

RÉSUMÉ

Bacteriophage ϕ6 is a segmented dsRNA virus with a lipid envelope, which are unusual traits in bacterial viruses but common in eukaryotic viruses. This uniqueness allowed ϕ6 and its Pseudomonad hosts to serve as a molecular model for RNA genetics, mutation, replication, packaging, and reassortment in both bacterial and eukaryotic viruses. However, an additional uniqueness of ϕ6, created by its high mutation rate, was its use as an experimental system to study key questions such as the evolution of sex (segment reassortment), host-pathogen interactions, mutational load, rates of adaptation, genetic and phenotypic complexity, and game theory.


Sujet(s)
Bactériophage phi-6 , Évolution moléculaire , Bactériophage phi-6/génétique , Bactériophage phi-6/physiologie , Virus à ARN/génétique , Interactions hôte-pathogène , Réplication virale , Mutation
10.
Viruses ; 16(7)2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-39066183

RÉSUMÉ

The viromes of freshwater bodies are underexplored. The Picornavirales order, with 371 acknowledged species, is one of the most expansive and diverse groups of eukaryotic RNA viruses. In this study, we add 513 picorna-like viruses to the assemblage of more than 2000 unassigned picorna-like viruses. Our set of the aquatic Picornavirales virome of the Teltow Canal in Berlin, Germany, consists of 239 complete and 274 partial genomes. This urban freshwater body is characterized by the predominance of marna-like viruses (30.8%) and dicistro-like viruses (19.1%), whereas picornaviruses, iflaviruses, solinvi-like viruses, polycipi-like viruses, and nora-like viruses are considerably less prevalent. Caliciviruses and secoviruses were absent in our sample. Although presenting characteristic domains of Picornavirales, more than 100 viruses (20.8%) could not be assigned to any of the 9 Picornavirales families. Thirty-three viruses of the Marnaviridae-mostly locarna-like viruses-exhibit a monocistronic genome layout. Besides a wealth of novel virus sequences, viruses with peculiar features are reported. Among these is a clade of untypeable marna-like viruses with dicistronic genomes, but with the capsid protein-encoding open reading frame located at the 5' part of their RNA. A virus with a similar genome layout but clustering with dicistroviruses was also observed. We further detected monocistronic viruses with a polymerase gene related to aparaviruses. The detection of Aichi virus and five novel posa-like viruses indicates a slight burden in municipal wastewater.


Sujet(s)
Génome viral , Phylogenèse , Picornaviridae , Picornaviridae/génétique , Picornaviridae/classification , Picornaviridae/isolement et purification , Berlin , Eau douce/virologie , Virome/génétique , ARN viral/génétique , Allemagne , Variation génétique , Virus à ARN/génétique , Virus à ARN/classification , Virus à ARN/isolement et purification
11.
Viruses ; 16(7)2024 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-39066243

RÉSUMÉ

Plus, minus, and double-strand RNA viruses are all found in nature. We use computational models to study the relative success of these strategies. We consider translation, replication, and virion assembly inside one cell, and transmission of virions between cells. For viruses which do not incorporate a polymerase in the capsid, transmission of only plus strands is the default strategy because virions containing minus strands are not infectious. Packaging only plus strands has a significant advantage if the number of RNA strands produced per cell is larger than the number of capsids. In this case, by not packaging minus strands, the virus produces more plus-strand virions. Therefore, plus-strand viruses are selected at low multiplicity of infection. However, at high multiplicity of infection, it is preferable to package both strands because the additional minus virions produced are helpful when there are multiple infections per cell. The fact that plus-strand viruses are widespread while viruses that package both strands are not seen in nature suggests that RNA strands are indeed produced in excess over capsids, and that the multiplicity of infection is not sufficiently high to favor the production of both kinds of virions. For double-strand viruses, we show that it is advantageous to produce only plus strands from the double strand within the cell, as is observed in real viruses. The reason for the success of minus-strand viruses is more puzzling initially. For viruses that incorporate a polymerase in the virion, minus virions are infectious. However, this is not sufficient to explain the success of minus-strand viruses, because in this case, viruses that package both strands outcompete those that package only minus or only plus. Real minus-strand viruses make use of replicable strands that are coated by a nucleoprotein, and separate translatable plus strands that are uncoated. Here we show that when there are distinct replicable and translatable strands, minus-strand viruses are selected.


Sujet(s)
Virus à ARN , ARN viral , Assemblage viral , Réplication virale , Virus à ARN/génétique , Virus à ARN/physiologie , ARN viral/génétique , ARN viral/métabolisme , Virion/génétique , Évolution moléculaire , Capside/métabolisme
12.
Viruses ; 16(7)2024 Jul 17.
Article de Anglais | MEDLINE | ID: mdl-39066314

RÉSUMÉ

Rice sheath blight, caused by the soil-borne fungus Rhizoctonia solani (teleomorph: Thanatephorus cucumeris, Basidiomycota), is one of the most devastating phytopathogenic fungal diseases and causes yield loss. Here, we report on a very high prevalence (100%) of potential virus-associated double-stranded RNA (dsRNA) elements for a collection of 39 fungal strains of R. solani from the rice sheath blight samples from at least four major rice-growing areas in the Philippines and a reference isolate from the International Rice Research Institute, showing different colony phenotypes. Their dsRNA profiles suggested the presence of multiple viral infections among these Philippine R. solani populations. Using next-generation sequencing, the viral sequences of the three representative R. solani strains (Ilo-Rs-6, Tar-Rs-3, and Tar-Rs-5) from different rice-growing areas revealed the presence of at least 36 viruses or virus-like agents, with the Tar-Rs-3 strain harboring the largest number of viruses (at least 20 in total). These mycoviruses or their candidates are believed to have single-stranded RNA or dsRNA genomes and they belong to or are associated with the orders Martellivirales, Hepelivirales, Durnavirales, Cryppavirales, Ourlivirales, and Ghabrivirales based on their coding-complete RNA-dependent RNA polymerase sequences. The complete genome sequences of two novel RNA viruses belonging to the proposed family Phlegiviridae and family Mitoviridae were determined.


Sujet(s)
Oryza , Phylogenèse , Maladies des plantes , Virus à ARN , Rhizoctonia , Rhizoctonia/virologie , Rhizoctonia/génétique , Maladies des plantes/microbiologie , Maladies des plantes/virologie , Oryza/microbiologie , Oryza/virologie , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , Génome viral , ARN viral/génétique , Séquençage nucléotidique à haut débit , ARN double brin/génétique , Virus fongiques/génétique , Virus fongiques/classification , Virus fongiques/isolement et purification , Philippines , Transcriptome
13.
Acta Trop ; 257: 107316, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38971572

RÉSUMÉ

An epidemiological survey of honey bee viruses was conducted on 87 clinically healthy beehives located in southeastern Morocco. The sampled colonies were analyzed by reverse transcriptase (RT)-PCR / Real Time RT-qPCR with the aim of detecting and / or quantifying the following viruses: acute bee paralysis virus (ABPV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), sacbrood virus (SBV), black queen cell virus (BQCV), Kashmir bee virus (KBV) and Israeli acute paralysis virus (IAPV). With the exception of the last two of these viruses, all the other five were detected with different prevalence rates. DWV showed the highest prevalence rate (89.65 %), followed by BQCV (17.24 %), ABPV (8.04 %), CBPV (4.59 %), and SBV (2.29 %). This study represents the first molecular detection of BQCV in the country. Among all investigated colonies, only eight were virus free (9.2 %). By contrast, single infection was detected in 64.37 % of colonies, 21.8 % showed mixed infection with two viruses, while 4.6 % showed three. Nucleotide sequences of a portion of the DWV polyprotein gene obtained for six honey bee samples showed the greatest nucleotide identity with sequences of DWV from Sweden and Ireland. The negative effect of migratory beekeeping as opposed to stationary beekeeping was highlighted given that stationary beehives showed infection with up to three viruses only, while migratory beehives showed up to five viruses. The results of this study are of crucial importance as they shed light on the current status of honey bee health in southeastern Morocco.


Sujet(s)
Virus des insectes , Abeilles/virologie , Animaux , Maroc/épidémiologie , Virus des insectes/génétique , Virus des insectes/isolement et purification , Virus des insectes/classification , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , Réaction de polymérisation en chaine en temps réel , RT-PCR , Prévalence , Dicistroviridae/génétique , Dicistroviridae/isolement et purification , Maladies virales/épidémiologie , Maladies virales/virologie , Maladies virales/médecine vétérinaire , Phylogenèse
14.
Acta Trop ; 257: 107322, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39004112

RÉSUMÉ

Arboviruses have always been a significant public health concern. Metagenomic surveillance has expanded the number of novel, often unclassified arboviruses, especially mosquito-borne and mosquito-specific viruses. This report presents the first description of a novel single-stranded RNA virus, Wanghe virus, identified from mosquitoes that were collected in Shandong Province in 2022. In this study, a total of 4,795 mosquitoes were collected and then divided into 105 pools according to location and species. QRT-PCR and nested PCR were performed to confirm the presence of Wanghe virus, and its genomic features and phylogenetic relationships were further analyzed. Our results revealed that Wanghe virus was detected in 9 out of the 105 mosquito pools, resulting in a minimum infection rate (MIR) of 0.19 % (9/4,795). One complete genome sequence and three viral partial sequences were obtained from the Wanghe virus-positive pools. Pairwise distance analysis indicated that these amplified sequences shared high nucleotide identity. Phylogenetic analysis demonstrated that Wanghe virus is most closely related to Guiyang Solinvi-like virus 3, which belongs to Solinviviridae. Further analyses indicated that Wanghe virus is a new, unclassified member of Solinviviridae.


Sujet(s)
Culicidae , Génome viral , Phylogenèse , Animaux , Chine , Culicidae/virologie , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , ARN viral/génétique , Arbovirus/génétique , Arbovirus/isolement et purification , Arbovirus/classification , Vecteurs moustiques/virologie
15.
Vopr Virusol ; 69(3): 203-218, 2024 Jul 05.
Article de Russe | MEDLINE | ID: mdl-38996370

RÉSUMÉ

The basis for criteria of the taxonomic classification of DNA and RNA viruses based on data of the genomic sequencing are viewed in this review. The genomic sequences of viruses, which have genome represented by double-stranded DNA (orthopoxviruses as example), positive-sense single-stranded RNA (alphaviruses and flaviviruses as example), non-segmented negative-sense single-stranded RNA (filoviruses as example), segmented negative-sense single-stranded RNA (arenaviruses and phleboviruses as example) are analyzed. The levels of genetic variability that determine the assignment of compared viruses to taxa of various orders are established for each group of viruses.


Sujet(s)
Virus à ADN , Génome viral , Virus à ARN , Virus à ARN/génétique , Virus à ARN/classification , Virus à ADN/génétique , Virus à ADN/classification , Phylogenèse , Humains , Animaux , Génomique/méthodes , ARN viral/génétique , Variation génétique
16.
Adv Virus Res ; 119: 39-61, 2024.
Article de Anglais | MEDLINE | ID: mdl-38897708

RÉSUMÉ

RNA viruses are some of the most successful biological entities due their ability to adapt and evolve. Despite their small genome and parasitic nature, RNA viruses have evolved many mechanisms to ensure their survival and maintenance in the host population. We propose that one of these mechanisms of survival is the generation of nonstandard viral genomes (nsVGs) that accumulate during viral replication. NsVGs are often considered to be accidental defective byproducts of the RNA virus replication, but their ubiquity and the plethora of roles they have during infection indicate that they are an integral part of the virus life cycle. Here we review the different types of nsVGs and discuss how their multiple roles during infection could be beneficial for RNA viruses to be maintained in nature. By shifting our perspectives on what makes a virus successful, we posit that nsVG generation is a conserved phenomenon that arose during RNA virus evolution as an essential component of a healthy virus community.


Sujet(s)
Évolution moléculaire , Génome viral , Virus à ARN , Réplication virale , Virus à ARN/génétique , Virus à ARN/physiologie , Réplication virale/génétique , Humains , Animaux , ARN viral/génétique , Infections à virus à ARN/virologie
17.
Int J Mol Sci ; 25(11)2024 May 26.
Article de Anglais | MEDLINE | ID: mdl-38891989

RÉSUMÉ

Negeviruses are insect-specific enveloped RNA viruses that exhibit a wide geographic distribution. A novel nege-like virus, tentatively named Aphis gossypii nege-like virus (AGNLV, GenBank: OR880429.1), was isolated from aphids (Aphis gossypii) in Lijiang City, Yunnan, China. AGNLV has a genome sequence of 9258 nt (excluding the polyA tail) encoding three open reading frames (ORFs). ORF1 (7149 nt) encodes a viral methyltransferase, a viral RNA helicase, and an RNA-dependent RNA polymerase. ORF2 (1422 nt) encodes a DiSB-ORF2_chro domain and ORF3 encodes an SP24 domain. The genome sequence of AGNLV shares the highest nucleotide identity of 60.0% and 59.5% with Wuhan house centipede virus 1 (WHCV1) and Astegopteryx formosana nege-like virus (AFNLV), respectively. Phylogenetic analysis based on the RNA-dependent RNA polymerase shows that AGNLV is clustered with other negeviruses and nege-like viruses discovered in aphids, forming a distinct "unclassified clade". Interestingly, AGNLV only encodes three ORFs, whereas AFNLV and WHCV1 have four ORFs. Structure and transmembrane domain predictions show the presence of eight alpha helices and five transmembrane helices in the AGNLV ORF3. Translational enhancement of the AGNLV 5' UTR was similar to that of the 5' UTR of plant viruses. Our findings provide evidence of the diversity and structure of nege-like viruses and are the first record of such a virus from a member of the genus Aphis.


Sujet(s)
Aphides , Génome viral , Cadres ouverts de lecture , Phylogenèse , Animaux , Aphides/virologie , Chine , Virus à ARN/génétique , Virus à ARN/isolement et purification , Virus à ARN/classification , RNA replicase/génétique , Protéines virales/génétique , Protéines virales/composition chimique , Virus des insectes/génétique , Virus des insectes/isolement et purification , Virus des insectes/classification , ARN viral/génétique
18.
Methods Mol Biol ; 2822: 77-86, 2024.
Article de Anglais | MEDLINE | ID: mdl-38907913

RÉSUMÉ

Foodborne viruses remain the largest cause of human gastroenteritis and one of the largest contributors to foodborne illnesses worldwide. Currently, quantitative reverse transcription PCR (qRT-PCR) or real-time qPCR are the detection methods commonly used for quantification of foodborne viruses, but those methods have several disadvantages, such as relying on standard curves for quantification and the background noise from a bulk reaction. ddPCR uses an oil-water emulsion to form multiple droplets that partition small amounts of viral genetic material (DNA or RNA) into each of the droplets. These droplets then undergo amplification cycles and are analyzed using Poisson distributions. This allows for absolute quantification without the need for a standard curve, which makes ddPCR a precise tool in surveillance of foodborne viruses. Herein, we describe the process of detecting foodborne viruses using RNA isolated from various matrices. Up to 96 samples including the positive and negative controls can be analyzed on a single plate by ddPCR.


Sujet(s)
Maladies d'origine alimentaire , Virus à ARN , ARN viral , RT-PCR , ARN viral/génétique , Humains , Maladies d'origine alimentaire/virologie , RT-PCR/méthodes , Virus à ARN/génétique , Virus à ARN/isolement et purification , Microbiologie alimentaire/méthodes , Réaction de polymérisation en chaine en temps réel/méthodes
19.
Curr Microbiol ; 81(7): 210, 2024 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-38837067

RÉSUMÉ

The extensive use of high-throughput sequencing (HTS) has significantly advanced and transformed our comprehension of virus diversity, especially in intricate settings like soil and biological specimens. In this study, we delved into mycovirus sequence surveys within mycorrhizal fungus species Terfezia claveryi, through employing HTS with total double-stranded RNA (dsRNA) extracts. Our findings revealed the presence of four distinct members from the Alsuviricetes class, one flexivirus designated as Terfezia claveryi flexivirus 1 (TcFV1) and three endornaviruses (TcEV1, TcEV2, and TcEV3) in two different T. claveryi isolates. TcFV1, a member of the order Tymovirales, exhibits a unique genome structure and sequence features. Through in-depth analyses, we found that it shares sequence similarities with other deltaflexiviruses and challenges existing Deltaflexiviridae classification. The discovery of TcFV1 adds to the genomic plasticity of mycoviruses within the Tymovirales order, shedding light on their evolutionary adaptations. Additionally, the three newly discovered endornaviruses (TcEV1, TcEV2, and TcEV3) in T. claveryi exhibited limited sequence similarities with other endornaviruses and distinctive features, including conserved domains like DEAD-like helicase, ATPases Associated with Diverse Cellular Activities (AAA ATPase), and RNA dependent RNA polymerase (RdRp), indicating their classification as members of new species within the Alphaendornavirus genus. In conclusion, this research emphasizes the importance of exploring viral diversity in uncultivated fungi, bridging knowledge gaps in mycovirus ecology. The discoveries of a novel flexivirus with unique genome organization and endornaviruses in T. claveryi broaden our comprehension of mycovirus diversity and evolution, highlighting the need for continued investigations into viral populations in wild fungi.


Sujet(s)
Virus fongiques , Génome viral , Mycorhizes , Phylogenèse , Virus fongiques/génétique , Virus fongiques/classification , Virus fongiques/isolement et purification , Mycorhizes/génétique , Mycorhizes/virologie , Mycorhizes/classification , Virus à ARN/génétique , Virus à ARN/classification , Virus à ARN/isolement et purification , ARN viral/génétique , Séquençage nucléotidique à haut débit , Basidiomycota/virologie , Basidiomycota/génétique
20.
Virology ; 597: 110141, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38917691

RÉSUMÉ

Alpha-synuclein (α-syn), known for its pivotal role in Parkinson's disease, has recently emerged as a significant player in neurotropic RNA virus infections. Upregulation of α-syn in various viral infections has been found to impact neuroprotective functions by regulating neurotransmitter synthesis, vesicle trafficking, and synaptic vesicle recycling. This review focuses on the multifaceted role of α-syn in controlling viral replication by modulating chemoattractant properties towards microglial cells, virus-induced ER stress signaling, anti-oxidative proteins expression. Furthermore, the text underlines the α-syn-mediated regulation of interferon-stimulated genes. The review may help suggest potential therapeutic avenues for mitigating the impact of RNA viruses on the central nervous system by exploiting α-syn neuroprotective biology.


Sujet(s)
Virus à ARN , alpha-Synucléine , alpha-Synucléine/métabolisme , alpha-Synucléine/génétique , Humains , Virus à ARN/physiologie , Virus à ARN/génétique , Animaux , Infections à virus à ARN/virologie , Infections à virus à ARN/immunologie , Infections à virus à ARN/métabolisme , Réplication virale , Neurones/virologie , Neurones/métabolisme , Microglie/virologie , Microglie/métabolisme , Stress du réticulum endoplasmique , Transduction du signal
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