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1.
Plant Dis ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38932448

RESUMO

Tomato interveinal chlorosis virus (ToICV; Begomovirus solanumintervenae, genus Begomovirus, family Geminiviridae) has been described infecting tomato (Solanum lycopersicum) and Macroptilium lathyroides in Northeastern (NE) Brazil for more than a decade (Albuquerque et al., 2012; Silva et al., 2012). During a survey in 2020, plants of the leguminous weed Rhynchosia minima exhibiting virus-like symptoms such as mosaic and interveinal chlorosis were observed in the state of Alagoas, NE Brazil. Symptomatic leaf samples of R. minima were randomly collected (n=15; supplementary figure 1). Total DNA from each sample was used as a template for PCR amplification of partial begomoviral DNA-A sequences using the degenerate primer pair PAL1v1978 and PAR1c496, universal for geminiviruses (Rojas et al., 1993). Amplicons of ~1.2 kbp were observed from 12 samples, although this should not be considered as incidence since only symptomatic plants were collected. To identify the begomovirus associated with R. minima, viral genomes were amplified from PCR-positive samples using rolling circle amplification (RCA) (Inoue-Nagata et al., 2004). The RCA products were digested with HindIII, cloned into the pBluescript II KS+ plasmid vector and bidirectionally Sanger-sequenced (Macrogen Inc., Seoul). BLASTn searches indicated that the clones (n=4) reported here corresponded to a begomovirus DNA-A component, and pairwise comparisons showed that they shared the highest identity with ToICV, at 92.4-94.7% nucleotide sequence identity. Based on the species demarcation criteria of ≥91% nucleotide identity for the genus Begomovirus (Brown et al., 2015), the begomoviruses obtained from R. minima are new isolates of ToICV. The new DNA-A sequences of 2,619-2,623 nt in length were deposited in GenBank under accession numbers PP639092 to PP639095. Multiple nucleotide sequence alignments were prepared using the MUSCLE algorithm implemented in MEGA v.11 (Kumar et al., 2018), and a maximum likelihood (ML) tree was reconstructed in RaxML-NG (Kozlov et al., 2019), assuming a general time reversible (GTR) nucleotide substitution model with a gamma (G) model of rate heterogeneity and 1,000 bootstrap replicates. The DNA-A-based tree showed that the ToICV sequences clustered into a monophyletic group, additionally supporting these isolates as members of the species Begomovirus solanumintervenae. At least two independent interspecies recombination events were predicted among the ToICV isolates, with breakpoints located in the Rep-encoding region and ToICV (GenBank Accession JF803253), tomato mottle leaf curl virus (JF803248) and soybean blistering mosaic virus (MN486865) detected as putative parents. To the best of our knowledge, this is the first report of ToICV infecting R. minima worldwide, expanding the host range of this begomovirus. Non-cultivated plants such as R. minima play a crucial role as reservoirs and sources of inoculum for begomoviruses (Paz-Carrasco et al., 2014), reinforcing their relevance to socioeconomically important crops.

3.
Viruses ; 15(10)2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37896851

RESUMO

Mixed infection between two or more begomoviruses is commonly found in tomato fields and can affect disease outcomes by increasing symptom severity and viral accumulation compared with single infection. Viruses that affect tomato include tomato severe rugose virus (ToSRV) and tomato rugose mosaic virus (ToRMV). Previous work showed that in mixed infection, ToRMV negatively affects the infectivity and accumulation of ToSRV. ToSRV and ToRMV share a high degree of sequence identity, including cis-elements in the common region (CR) and their specific recognition sites (iteron-related domain, IRD) within the Rep gene. Here, we investigated if divergent sites in the CR and IRD are involved in the interaction between these two begomoviruses. ToSRV clones were constructed containing the same nucleotides as ToRMV in the CR (ToSRV-A(ToR:CR)), IRD (ToSRV-A(ToR:IRD)) and in both regions (ToSRV-A(ToR:CR+IRD)). When plants were co-inoculated with ToRMV and ToSRV-A(ToR:IRD), the infectivity and accumulation of ToSRV were negatively affected. In mixed inoculation of ToRMV with ToSRV-A(ToR:CR), high infectivity of both viruses and high DNA accumulation of ToSRV-A(ToR:CR) were observed. A decrease in viral accumulation was observed in plants inoculated with ToSRV-A(ToR:CR+IRD). These results indicate that differences in the CR, but not the IRD, are responsible for the negative interference of ToRMV on ToSRV.


Assuntos
Begomovirus , Coinfecção , Vírus do Mosaico , Solanum lycopersicum , Begomovirus/genética , Nucleotídeos , Doenças das Plantas , Plantas , DNA Viral/genética , Vírus do Mosaico/genética
4.
Arch Virol ; 168(9): 223, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37561218

RESUMO

The phylum Cressdnaviricota comprises viruses with single-stranded, circular DNA genomes that encode an HUH-type endonuclease (known as Rep). The phylum includes two classes, eight orders, and 11 families. Here, we report the creation of a twelfth family in the order Mulpavirales, class Arfiviricetes of the phylum Cressdnaviricota. The family Amesuviridae comprises viruses that infect plants and is divided into two genera: Temfrudevirus, including the species Temfrudevirus temperatum (with temperate fruit decay-associated virus as a member), and Yermavirus, including the species Yermavirus ilicis (with yerba mate-associated circular DNA virus as a member). Both viruses encode Rep proteins with HUH endonuclease and SH3 superfamily helicase domains. Phylogenetic analysis indicates that the replicative module of amesuviruses constitutes a well-supported monophyletic clade related to Rep proteins from viruses in the order Mulpavirales. Furthermore, both viruses encode a single capsid protein (CP) related to geminivirus CPs. Phylogenetic incongruence between the replicative and structural modules of amesuviruses suggests a chimeric origin resulting from remote recombination events between ancestral mulpavirales and geminivirids. The creation of the family Amesuviridae has been ratified by the International Committee on Taxonomy of Viruses (ICTV).


Assuntos
Vírus de DNA , Vírus de Plantas , Vírus de DNA/classificação , Vírus de DNA/isolamento & purificação , DNA Circular/genética , DNA de Cadeia Simples/genética , Endonucleases/genética , Geminiviridae/genética , Genoma Viral/genética , Filogenia , Vírus de Plantas/genética
5.
Arch Virol ; 168(7): 175, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37296227

RESUMO

This article reports changes to virus taxonomy and taxon nomenclature that were approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in April 2023. The entire ICTV membership was invited to vote on 174 taxonomic proposals that had been approved by the ICTV Executive Committee in July 2022, as well as a proposed revision of the ICTV Statutes. All proposals and the revised ICTV Statutes were approved by a majority of the voting membership. Of note, the ICTV continued the process of renaming existing species in accordance with the recently mandated binomial format and included gene transfer agents (GTAs) in the classification framework by classifying them as viriforms. In total, one class, seven orders, 31 families, 214 genera, and 858 species were created.


Assuntos
Vírus , Humanos , Vírus/genética , Membro de Comitê
7.
Arch Virol ; 167(11): 2429-2440, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35999326

RESUMO

This article reports the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in March 2022. The entire ICTV was invited to vote on 174 taxonomic proposals approved by the ICTV Executive Committee at its annual meeting in July 2021. All proposals were ratified by an absolute majority of the ICTV members. Of note, the Study Groups have started to implement the new rule for uniform virus species naming that became effective in 2021 and mandates the binomial 'Genus_name species_epithet' format with or without Latinization. As a result of this ratification, the names of 6,481 virus species (more than 60 percent of all species names currently recognized by ICTV) now follow this format.


Assuntos
Vírus , Membro de Comitê , Vírus/genética
8.
Arch Virol ; 167(4): 1231-1234, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35043230

RESUMO

Following the results of the International Committee on Taxonomy of Viruses (ICTV) Ratification Vote held in March 2021, a standard two-part "binomial nomenclature" is now the norm for naming virus species. Adoption of the new nomenclature is still in its infancy; thus, it is timely to reiterate the distinction between "virus" and "virus species" and to provide guidelines for naming and writing them correctly.


Assuntos
Vírus não Classificados , Vírus , Vírus de DNA , Vírus/genética , Redação
9.
Pathogens ; 10(10)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34684193

RESUMO

Begomoviruses can be found in association with alphasatellites, which are capable of autonomous replication but are dependent on the helper begomovirus for systemic infection, encapsidation and vector transmission. Previous studies suggest that the presence of NW alphasatellites (genus Clecrusatellite) is associated with more severe symptoms. To better understand this interaction, we investigated the effects of two alphasatellites on infectivity, symptom development, viral DNA accumulation and vector transmission of three begomoviruses in three hosts. In tomato and Nicotiana benthamiana, all combinations were infectious. In Leonurus sibiricus, only the ToYSV/ToYSA combination was infectious. The presence of EuYMA increased symptom severity of EuYMV and ToYSV in N. benthamiana, and the presence of ToYSA was associated with more severe symptoms of ToYSV in N. benthamiana and L. sibiricus. EuYMA increased the accumulation of ToYSV in N. benthamiana but reduced the accumulation of EuYMV in tomato and of ToSRV in N. benthamiana. The presence of ToYSA decreased the accumulation of ToYSV in N. benthamiana and L. sibiricus. ToYSA negatively affected transmission of ToSRV by Bemisia tabaci MEAM1. Together, our results indicate that NW alphasatellites can interact with different begomoviruses, increasing symptom severity and interfering in the transmission of the helper begomovirus. Understanding this interaction is important as it may affect the emergence of diseases caused by begomovirus-alphasatellite complexes in the field.

10.
Arch Virol ; 166(9): 2633-2648, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34231026

RESUMO

This article reports the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in March 2021. The entire ICTV was invited to vote on 290 taxonomic proposals approved by the ICTV Executive Committee at its meeting in October 2020, as well as on the proposed revision of the International Code of Virus Classification and Nomenclature (ICVCN). All proposals and the revision were ratified by an absolute majority of the ICTV members. Of note, ICTV mandated a uniform rule for virus species naming, which will follow the binomial 'genus-species' format with or without Latinized species epithets. The Study Groups are requested to convert all previously established species names to the new format. ICTV has also abolished the notion of a type species, i.e., a species chosen to serve as a name-bearing type of a virus genus. The remit of ICTV has been clarified through an official definition of 'virus' and several other types of mobile genetic elements. The ICVCN and ICTV Statutes have been amended to reflect these changes.


Assuntos
Classificação/métodos , Filogenia , Vírus não Classificados/classificação , Vírus/classificação , Cooperação Internacional , Viroides/classificação , Vírus/genética , Vírus/isolamento & purificação , Vírus não Classificados/genética , Vírus não Classificados/isolamento & purificação
11.
Arch Virol ; 165(11): 2737-2748, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32816125

RESUMO

This article reports the changes to virus classification and taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in March 2020. The entire ICTV was invited to vote on 206 taxonomic proposals approved by the ICTV Executive Committee at its meeting in July 2019, as well as on the proposed revision of the ICTV Statutes. All proposals and the revision of the Statutes were approved by an absolute majority of the ICTV voting membership. Of note, ICTV has approved a proposal that extends the previously established realm Riboviria to encompass nearly all RNA viruses and reverse-transcribing viruses, and approved three separate proposals to establish three realms for viruses with DNA genomes.


Assuntos
Classificação/métodos , Vírus/classificação , Terminologia como Assunto , Virologia/organização & administração , Vírus/isolamento & purificação
12.
Arch Virol ; 165(5): 1263-1264, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32065315

RESUMO

The article Binomial nomenclature for virus species: a consultation, written by Stuart G. Siddell, Peter J. Walker, Elliot J. Lefkowitz, Arcady R. Mushegian, Bas E. Dutilh.

13.
Arch Virol ; 165(2): 519-525, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31797129

RESUMO

The Executive Committee of the International Committee on Taxonomy of Viruses (ICTV) recognizes the need for a standardized nomenclature for virus species. This article sets out the case for establishing a binomial nomenclature and presents the advantages and disadvantages of different naming formats. The Executive Committee understands that adopting a binomial system would have major practical consequences, and invites comments from the virology community before making any decisions to change the existing nomenclature. The Executive Committee will take account of these comments in deciding whether to approve a standardized binomial system at its next meeting in October 2020. Note that this system would relate only to the formal names of virus species and not to the names of viruses.


Assuntos
Classificação/métodos , Terminologia como Assunto , Vírus/classificação
14.
Arch Virol ; 164(9): 2417-2429, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31187277

RESUMO

This article reports the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in February 2019. Of note, in addition to seven new virus families, the ICTV has approved, by an absolute majority, the creation of the realm Riboviria, a likely monophyletic group encompassing all viruses with positive-strand, negative-strand and double-strand genomic RNA that use cognate RNA-directed RNA polymerases for replication.


Assuntos
Virologia/organização & administração , Vírus/classificação , Membro de Comitê , RNA Viral/genética , Terminologia como Assunto , Virologia/normas , Vírus/genética , Vírus/isolamento & purificação
15.
Annu Rev Virol ; 6(1): 411-433, 2019 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-31180812

RESUMO

Viruses constitute the largest group of emerging pathogens, and geminiviruses (plant viruses with circular, single-stranded DNA genomes) are the major group of emerging plant viruses. With their high potential for genetic variation due to mutation and recombination, their efficient spread by vectors, and their wide host range as a group, including both wild and cultivated hosts, geminiviruses are attractive models for the study of the evolutionary and ecological factors driving virus emergence. Studies on the epidemiological features of geminivirus diseases have traditionally focused primarily on crop plants. Nevertheless, knowledge of geminivirus infection in wild plants, and especially at the interface between wild and cultivated plants, is necessary to provide a complete view of their ecology, evolution, and emergence. In this review, we address the most relevant aspects of geminivirus variability and evolution in wild and crop plants and geminiviruses' potential to emerge in crops.


Assuntos
Geminiviridae/fisiologia , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Plantas/virologia , Ecologia , Evolução Molecular , Geminiviridae/classificação , Geminiviridae/genética , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/genética
16.
Arch Virol ; 164(3): 943-946, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663020

RESUMO

This article reports the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in October 2018. Of note, the ICTV has approved, by an absolute majority, the creation of additional taxonomical ranks above those recognized previously. A total of 15 ranks (realm, subrealm, kingdom, subkingdom, phylum, subphylum, class, subclass, order, suborder, family, subfamily, genus, subgenus, and species) are now available to encompass the entire spectrum of virus diversity. Classification at ranks above genus is not obligatory but can be used by the authors of new taxonomic proposals when scientific justification is provided.


Assuntos
Vírus/classificação , Filogenia , Virologia/organização & administração , Vírus/genética , Vírus/isolamento & purificação
17.
Syst Biol ; 68(5): 828-839, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597118

RESUMO

The International Committee on Taxonomy of Viruses (ICTV) is tasked with classifying viruses into taxa (phyla to species) and devising taxon names. Virus names and virus name abbreviations are currently not within the ICTV's official remit and are not regulated by an official entity. Many scientists, medical/veterinary professionals, and regulatory agencies do not address evolutionary questions nor are they concerned with the hierarchical organization of the viral world, and therefore, have limited use for ICTV-devised taxa. Instead, these professionals look to the ICTV as an expert point source that provides the most current taxonomic affiliations of viruses of interests to facilitate document writing. These needs are currently unmet as an ICTV-supported, easily searchable database that includes all published virus names and abbreviations linked to their taxa is not available. In addition, in stark contrast to other biological taxonomic frameworks, virus taxonomy currently permits individual species to have several members. Consequently, confusion emerges among those who are not aware of the difference between taxa and viruses, and because certain well-known viruses cannot be located in ICTV publications or be linked to their species. In addition, the number of duplicate names and abbreviations has increased dramatically in the literature. To solve this conundrum, the ICTV could mandate listing all viruses of established species and all reported unclassified viruses in forthcoming online ICTV Reports and create a searchable webpage using this information. The International Union of Microbiology Societies could also consider changing the mandate of the ICTV to include the nomenclature of all viruses in addition to taxon considerations. With such a mandate expansion, official virus names and virus name abbreviations could be catalogued and virus nomenclature could be standardized. As a result, the ICTV would become an even more useful resource for all stakeholders in virology.


Assuntos
Classificação/métodos , Virologia/métodos , Vírus/classificação , Cooperação Internacional , Virologia/normas , Virologia/tendências
18.
Arch Virol ; 163(11): 3163-3166, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30032448

RESUMO

Gemycircularviruses (genus Gemycircularvirus, family Genomoviridae) are single-stranded DNA viruses that are spread around the world in association with several organisms and environments. In this work, we identified two gemycircularviruses associated with two non-cultivated plants in Brazil, Momordica charantia and Euphorbia heterophylla. Both viruses display the general genome structure of gemycircularviruses. The virus isolated from M. charantia showed the highest nucleotide sequence identity with Pteropus associated gemycircularvirus 5, and an atypical structure consisting of a hairpin embedded in the major stem-loop was observed in the intergenic region. The virus from E. heterophylla showed the highest nucleotide sequence identity with Odonata associated gemycircularvirus 1. Phylogenetic analysis groups the two new viruses together with other genomoviruses of the genus Gemycircularvirus.


Assuntos
Vírus de DNA/genética , Euphorbia/virologia , Genoma Viral , Momordica charantia/virologia , Doenças das Plantas/virologia , Vírus de Plantas/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Brasil , Vírus de DNA/classificação , Vírus de DNA/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/genética , Análise de Sequência de DNA
19.
Arch Virol ; 163(9): 2601-2631, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29754305

RESUMO

This article lists the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses in February 2018. A total of 451 species, 69 genera, 11 subfamilies, 9 families and one new order were added to the taxonomy. The current totals at each taxonomic level now stand at 9 orders, 131 families, 46 subfamilies, 803 genera and 4853 species. A change was made to the International Code of Virus Classification and Nomenclature to allow the use of the names of people in taxon names under appropriate circumstances. An updated Master Species List incorporating the approved changes was released in March 2018 ( https://talk.ictvonline.org/taxonomy/ ).


Assuntos
Vírus/classificação , Terminologia como Assunto , Virologia/organização & administração , Vírus/genética , Vírus/isolamento & purificação
20.
Virus Res ; 244: 21-26, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29024687

RESUMO

In the present work, we report a novel mycovirus that infects Alternaria alternata. The mycovirus has isometric particles of approximately 30nm and the genome consists of two molecules of dsRNA, dsRNA1 with 1833bp, encoding a putative RNA-dependent RNA polymerase (RdRp) and dsRNA2, with 1680bp in length, encoding the putative capsid protein (CP). RdRp analysis revealed low amino acid identity with RdRps with species in the genus Gammapartitivirus, and the alignment of the RdRp revealed all the six conserved motifs present in members of Partitiviridae. The putative coat protein (CP) analysis revealed similarity with the putative CP of Botryosphaeria dothidea partitivirus 1 (BdPV1), a divergent partitivirus. We propose that Alternaria alternata partitivirus 1 (AtPV1) is a novel species and comprises a distinct lineage related to genus Gammapartitivirus in the family Partitiviridae, apparently on the threshold of radiation of a new genus, together with BdPV1. Vertical transmission tests showed that AtPV1 was transmitted to 100% conidial progeny and standard curing was unable to eliminate it from the host, characterizing it as a persistent virus. The absence of a virus-free isogenic lineage prevented us from accessing the details of the interaction between AtPV1 and A. alternata. Therefore, it remains unclear whether the morphological plasticity observed or the inability of the A. alternata isolate AVi1 to cause disease in plants is associated with AtPV1 infection.


Assuntos
Alternaria/virologia , Micovírus/genética , Genoma Viral , Filogenia , Vírus de RNA/genética , RNA Viral/genética , Sequência de Bases , Proteínas do Capsídeo/genética , Micovírus/classificação , Genótipo , Interações Microbianas , Fenótipo , Vírus de RNA/classificação , RNA de Cadeia Dupla/genética , RNA Polimerase Dependente de RNA/genética , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
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