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1.
Microbiol Resour Announc ; 13(9): e0030124, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39083695

RESUMO

Complete sequences of RNA1 and RNA2 of tulip streak virus (TuSV) were already reported, but other segments were not yet. In this study, we reported RNA3 and RNA4 of TuSV, which shared around 69% nucleotide identity with those of closely related virus, suggesting that these are additional RNA segments.

2.
Microbiol Resour Announc ; 13(1): e0080723, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38117063

RESUMO

This is a report of a complete genome sequence of bean common mosaic virus in Vietnam. This virus shares around 99% nucleotide identity with a Nepal isolate.

3.
J Gen Virol ; 104(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37702592

RESUMO

The family Phenuiviridae comprises viruses with 2-8 segments of negative-sense or ambisense RNA, comprising 8.1-25.1 kb in total. Virions are typically enveloped with spherical or pleomorphic morphology but can also be non-enveloped filaments. Phenuivirids infect animals including livestock and humans, birds, plants or fungi, as well as arthropods that serve as single hosts or act as biological vectors for transmission to animals or plants. Phenuivirids include important pathogens of humans, livestock, seafood and agricultural crops. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Phenuiviridae, which is available at ictv.global/report/phenuiviridae.


Assuntos
Artrópodes , Vírus de RNA , Animais , Humanos , Vírus de RNA/genética , Vírion , RNA
4.
J Virol ; 97(6): e0022123, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37199623

RESUMO

Plant viruses depend on a number of host factors for successful infection. Deficiency of critical host factors confers recessively inherited viral resistance in plants. For example, loss of Essential for poteXvirus Accumulation 1 (EXA1) in Arabidopsis thaliana confers resistance to potexviruses. However, the molecular mechanism of how EXA1 assists potexvirus infection remains largely unknown. Previous studies reported that the salicylic acid (SA) pathway is upregulated in exa1 mutants, and EXA1 modulates hypersensitive response-related cell death during EDS1-dependent effector-triggered immunity. Here, we show that exa1-mediated viral resistance is mostly independent of SA and EDS1 pathways. We demonstrate that Arabidopsis EXA1 interacts with three members of the eukaryotic translation initiation factor 4E (eIF4E) family, eIF4E1, eIFiso4E, and novel cap-binding protein (nCBP), through the eIF4E-binding motif (4EBM). Expression of EXA1 in exa1 mutants restored infection by the potexvirus Plantago asiatica mosaic virus (PlAMV), but EXA1 with mutations in 4EBM only partially restored infection. In virus inoculation experiments using Arabidopsis knockout mutants, EXA1 promoted PlAMV infection in concert with nCBP, but the functions of eIFiso4E and nCBP in promoting PlAMV infection were redundant. By contrast, the promotion of PlAMV infection by eIF4E1 was, at least partially, EXA1 independent. Taken together, our results imply that the interaction of EXA1-eIF4E family members is essential for efficient PlAMV multiplication, although specific roles of three eIF4E family members in PlAMV infection differ. IMPORTANCE The genus Potexvirus comprises a group of plant RNA viruses, including viruses that cause serious damage to agricultural crops. We previously showed that loss of Essential for poteXvirus Accumulation 1 (EXA1) in Arabidopsis thaliana confers resistance to potexviruses. EXA1 may thus play a critical role in the success of potexvirus infection; hence, elucidation of its mechanism of action is crucial for understanding the infection process of potexviruses and for effective viral control. Previous studies reported that loss of EXA1 enhances plant immune responses, but our results indicate that this is not the primary mechanism of exa1-mediated viral resistance. Here, we show that Arabidopsis EXA1 assists infection by the potexvirus Plantago asiatica mosaic virus (PlAMV) by interacting with the eukaryotic translation initiation factor 4E family. Our results imply that EXA1 contributes to PlAMV multiplication by regulating translation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fator de Iniciação 4E em Eucariotos , Doenças das Plantas , Potexvirus , Arabidopsis/metabolismo , Arabidopsis/virologia , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Doenças das Plantas/genética , Potexvirus/fisiologia , Proteínas de Arabidopsis/metabolismo , Resistência à Doença/genética , Ligação Proteica , Motivos de Aminoácidos , Deleção de Genes , Células Vegetais/virologia , Biossíntese de Proteínas/genética
5.
Arch Virol ; 168(2): 48, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609794

RESUMO

In July 2018, pepper plants (Capsicum annuum L.) with chlorotic leaves and fruits were observed in Kochi prefecture, Japan. High-throughput sequencing (HTS) identified the possible presence of an ophiovirus-like virus possessing three RNA segments in a chlorotic leaf. Using Sanger sequencing with primers designed based on the HTS results and a different source of RNA from the one used for HTS, the complete nucleotide sequences of three RNA segments encoding four proteins on their complementary strand were determined. The amino acid sequences of these four proteins showed similarity to those of the RNA-dependent RNA polymerase, RNA-silencing suppressor protein, movement protein, and coat protein, respectively, of ophioviruses, which are negative-sense single-stranded RNA viruses. However, the coat protein amino acid sequence of the virus found on pepper plants was no more than 61.9% identical to those of any known ophioviruses, which is lower than the species demarcation threshold of 85 %. Hence, we suggest that this virus, which we have named "pepper chlorosis associated virus" (PepCaV) should be considered a member of a new species in the genus Ophiovirus, for which we propose the name "Ophiovirus capsici". The results of phylogenetic analysis using coat protein amino acid sequences of PepCaV and other ophioviruses also supported this conclusion. PepCaV RNA was found to have conserved nucleotide sequences at both the 5' and 3' termini of the different RNA segments, and the conserved terminal nucleotide sequences were predicted to form a self-complementary double-stranded region, resulting in a panhandle structure in each of the genomic RNAs.


Assuntos
Capsicum , Vírus de RNA , Japão , Filogenia , Vírus de RNA/genética , RNA Viral/genética
6.
J Virol Methods ; 312: 114662, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36455691

RESUMO

Yellowing symptoms caused by tomato chlorosis virus (ToCV) and tomato infectious chlorosis virus (TICV), both assigned to the genus Crinivirus, resemble nutrient deficiencies. Therefore, early diagnosis of infections will prevent crop damage and the spread of the viruses. In this study, we established a rapid detection method for ToCV and TICV by reverse transcription-loop-mediated isothermal amplification (RT-LAMP). We first designed primer sets for RT-LAMP specific for ToCV and TICV. Next, by selecting the optimum primer set and determining the optimum conditions for the RT-LAMP reaction, each virus was detected within 50 min by piercing the diseased area of a tomato leaf with a toothpick, immersing the toothpick in the reaction solution, and conducting the RT-LAMP reaction. To verify the accuracy of the procedure, 61 tomato leaf samples showing disease symptoms were collected from five regions of Indonesia, and the RT-LAMP results for the samples were identical to those obtained with the commonly used reverse transcription-polymerase chain reaction.


Assuntos
Crinivirus , Solanum lycopersicum , Crinivirus/genética , Doenças das Plantas
7.
Sci Rep ; 12(1): 13560, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945265

RESUMO

Members of the order Bunyavirales infect a wide variety of host species, including plants, animals and humans, and pose a threat to public health. Major families in this order have tri-segmented negative-sense RNA genomes, the 5' and 3' ends of which form complementary strands that serve as a replication promoter. Elucidation of the mechanisms by which viral polymerases recognize the promoter to initiate RNA synthesis is important for understanding viral replication and pathogenesis, and developing antivirals. A list of replication promoter configuration patterns may provide details on the differences in the replication mechanisms among bunyaviruses. By using public sequence data of all known bunyavirus species, we constructed a comprehensive list of the replication promoters comprising 40 nucleotides in both the 5' and 3' ends of the genome that form a specific complementary strand. Among tri-segmented bunyaviruses, members of the family Nairoviridae, including the highly pathogenic Crimean-Congo hemorrhagic fever virus, have evolved a GC-rich promoter structure differing from that of other families. The unique promoter structure might be related to the large genome size of the family Nairoviridae among bunyaviruses, and the large genome architecture might confer pathogenic advantages. The promoter list provided in this report is useful for predicting the virus family-specific replication mechanisms of bunyaviruses.


Assuntos
Bunyaviridae , Vírus da Febre Hemorrágica da Crimeia-Congo , Vírus de RNA , Animais , Bunyaviridae/química , Bunyaviridae/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Humanos , RNA , Vírus de RNA/genética , Replicação Viral/genética
8.
Virus Genes ; 58(5): 478-482, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35727492

RESUMO

Tomato mosaic virus (ToMV) is easily transmitted in soil and by contact. By these reasons, it is relatively difficult to control ToMV disease in tomato. Incorporation of the Tm-22 gene has been widely used as a control method for ToMV, but ToMV isolates that overcome this resistance gene have been reported worldwide in recent years. In this study, we determined the entire nucleotide sequences of ToMV isolate [named ToMV-KMT (LC650928)], which was isolated from tomato plants showing symptoms of systemic necrosis in Kumamoto prefecture, Japan. We also analyzed the viral gene of ToMV-KMT that overcome the Tm-22 gene by constructing its infectious cDNA clone and by generating chimeric viruses with a non-breaking strain. According to previous research, Tm-22 recognizes the viral movement protein (MP) and exerts resistance by inducing hypersensitive reaction or hypersensitive cell death. We discovered that a mutation in the 240th amino acid (aspartic acid to tyrosine) of the MP of ToMV-KMT, which may stabilize the protein's structure, is responsible for the ability of this isolate to overcome the resistance of Tm-22.


Assuntos
Vírus do Mosaico , Solanum lycopersicum , Tobamovirus , Ácido Aspártico/metabolismo , DNA Complementar/metabolismo , Solanum lycopersicum/genética , Vírus do Mosaico/genética , Doenças das Plantas/genética , Solo , Tobamovirus/genética , Tirosina/metabolismo , Proteínas Virais/genética
9.
Arch Virol ; 166(11): 3179-3182, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34498122

RESUMO

Dahlia is a major ornamental plant that is cultivated worldwide. However, dahlia plants, which are mainly propagated through vegetative reproduction, are susceptible to widespread damage by viruses, and viral control requires that the nature of the infecting virus(es) be known. In this study, dahlia common mosaic virus (DCMV) was detected for the first time in Japan and sequenced. This is the first report of an infectious DCMV clone being constructed, and it will aid in the characterization of DCMV.


Assuntos
Dahlia/virologia , Vírus do Mosaico/genética , Genoma Viral , Japão , Vírus do Mosaico/patogenicidade , Doenças das Plantas/virologia , Plântula/virologia
10.
J Gen Virol ; 102(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33226319

RESUMO

In Japan, tulip-growing areas have been plagued by viral diseases for decades, but the viruses causing the damage remain undescribed. In this study, Nicotiana benthamiana and Chenopodium quinoa plants mechanically inoculated with crude sap from a symptomatic tulip flower exhibited necrosis symptoms. Additionally, flexuous and filamentous virus particles were detected by electron microscopy analysis. Moreover, we determined the complete sequences of two genomic segments of the tulip streak virus (TuSV), which is a new virus associated with streaking symptoms, on the basis of a next-generation sequencing analysis. Homology analyses of the amino acid sequence of RNA-dependent RNA polymerase and the terminal sequence of the genomic RNA indicated that TuSV is associated with viruses in the family Phenuiviridae, but differs substantially from other reported viruses.


Assuntos
Doenças das Plantas/virologia , Potyviridae/genética , Tulipa/virologia , Sequência de Aminoácidos , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Japão , Filogenia , RNA Viral/genética , Proteínas Virais/genética , Vírion/ultraestrutura
11.
Microbiol Resour Announc ; 9(25)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32554790

RESUMO

We report a complete genome sequence of a pepper yellow leaf curl Indonesia virus (PepYLCIV) isolated in Bali, Indonesia. This virus shares around 90% identity with other PepYLCIV DNA-As and 86% identity with DNA-Bs, suggesting that it is a novel isolate of PepYLCIV.

12.
Sci Rep ; 9(1): 5958, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30976020

RESUMO

Since the propagation of plant viruses depends on various host susceptibility factors, deficiency in them can prevent viral infection in cultivated and model plants. Recently, we identified the susceptibility factor Essential for poteXvirus Accumulation 1 (EXA1) in Arabidopsis thaliana, and revealed that EXA1-mediated resistance was effective against three potexviruses. Although EXA1 homolog genes are found in tomato and rice, little is known about which viruses depend on EXA1 for their infection capability and whether the function of EXA1 homologs in viral infection is conserved across multiple plant species, including crops. To address these questions, we generated knockdown mutants using virus-induced gene silencing in two Solanaceae species, Nicotiana benthamiana and tomato. In N. benthamiana, silencing of an EXA1 homolog significantly compromised the accumulation of potexviruses and a lolavirus, a close relative of potexviruses, whereas transient expression of EXA1 homologs from tomato and rice complemented viral infection. EXA1 dependency for potexviral infection was also conserved in tomato. These results indicate that EXA1 is necessary for effective accumulation of potexviruses and a lolavirus, and that the function of EXA1 in viral infection is conserved among diverse plant species.


Assuntos
Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Nicotiana/virologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Potexvirus/fisiologia , Solanum lycopersicum/virologia , Doenças das Plantas/virologia , Proteínas de Plantas/genética
13.
Microbiol Resour Announc ; 8(15)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975814

RESUMO

This is the first report of a begomovirus infecting luffa in Indonesia. The genome of this virus shares a close identity with that of Tomato leaf curl New Delhi virus (ToLCNDV). There is a 36-nucleotide duplicated sequence in the DNA-B component, suggesting the occurrence of an intraviral recombination.

14.
J Virol Methods ; 265: 71-76, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30321578

RESUMO

The emergence of begomovirus infection is one of the most important problems affecting production of a variety of vegetable crops worldwide. Infection by begomoviruses has been detected and spread rapidly on Cucurbitaceae and Solanaceae plants in Indonesia. A rapid and simple detection assay for begomoviruses under field conditions for routine sampling of plants is needed. Primers for a loop-mediated isothermal amplification (LAMP) assay were designed based on the sequences of three Indonesian begomoviruses, namely Tomato leaf curl New Delhi virus (ToLCNDV), Pepper yellow leaf curl Indonesia virus (PepYLCIV), and Tomato yellow leaf curl Kanchanaburi virus (TYLCKaV), infecting Cucurbitaceae and Solanaceae plants. LAMP assays using a Genelyzer™ III portable fluorometer with a toothpick method successfully detected these begomoviruses in infected melon, pepper, and eggplant samples. LAMP assays conducted during a field survey for detection of the three begomoviruses on 104 fresh leaves indicated that most of the samples were positive; the findings were confirmed by PCR using universal primers of begomovirus as a common detection method. These results demonstrate that this simple and rapid LAMP assay using a fluorometer portable device may be used to achieve real-time detection of begomoviruses under field conditions.


Assuntos
Begomovirus/isolamento & purificação , Cucurbitaceae/virologia , Fluorometria/instrumentação , Fluorometria/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Doenças das Plantas/virologia , Solanaceae/virologia , Begomovirus/genética , Primers do DNA/genética , Indonésia , Folhas de Planta/virologia , Fatores de Tempo
15.
Genome Announc ; 6(7)2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29449391

RESUMO

The complete genome sequence of the first Japanese isolate of hibiscus latent Singapore virus (HLSV-J) was determined. The genomes of HLSV-J and a reported isolate from Singapore had only 86.7% nucleotide identity, while the encoded proteins shared amino acid identities of more than 95%.

16.
DNA Cell Biol ; 36(12): 1081-1092, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29039971

RESUMO

Phytoplasmas are obligate intracellular parasitic bacteria that infect both plants and insects. We previously identified the sigma factor RpoD-dependent consensus promoter sequence of phytoplasma. However, the genome-wide landscape of RNA transcripts, including non-coding RNAs (ncRNAs) and RpoD-independent promoter elements, was still unknown. In this study, we performed an improved RNA sequencing analysis for genome-wide identification of the transcription start sites (TSSs) and the consensus promoter sequences. We constructed cDNA libraries using a random adenine/thymine hexamer primer, in addition to a conventional random hexamer primer, for efficient sequencing of 5'-termini of AT-rich phytoplasma RNAs. We identified 231 TSSs, which were classified into four categories: mRNA TSSs, internal sense TSSs, antisense TSSs (asTSSs), and orphan TSSs (oTSSs). The presence of asTSSs and oTSSs indicated the genome-wide transcription of ncRNAs, which might act as regulatory ncRNAs in phytoplasmas. This is the first description of genome-wide phytoplasma ncRNAs. Using a de novo motif discovery program, we identified two consensus motif sequences located upstream of the TSSs. While one was almost identical to the RpoD-dependent consensus promoter sequence, the other was an unidentified novel motif, which might be recognized by another transcription initiation factor. These findings are valuable for understanding the regulatory mechanism of phytoplasma gene expression.


Assuntos
Phytoplasma/genética , Animais , Sequência de Bases , Sequência Conservada , Biblioteca Gênica , Genoma Bacteriano , Insetos/microbiologia , Phytoplasma/patogenicidade , Plantas/microbiologia , Regiões Promotoras Genéticas , RNA Bacteriano/genética , RNA não Traduzido/genética , Análise de Sequência de RNA , Sítio de Iniciação de Transcrição
17.
Sci Rep ; 7: 39678, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28059075

RESUMO

One of the important antiviral genetic strategies used in crop breeding is recessive resistance. Two eukaryotic translation initiation factor 4E family genes, eIF4E and eIFiso4E, are the most common recessive resistance genes whose absence inhibits infection by plant viruses in Potyviridae, Carmovirus, and Cucumovirus. Here, we show that another eIF4E family gene, nCBP, acts as a novel recessive resistance gene in Arabidopsis thaliana toward plant viruses in Alpha- and Betaflexiviridae. We found that infection by Plantago asiatica mosaic virus (PlAMV), a potexvirus, was delayed in ncbp mutants of A. thaliana. Virus replication efficiency did not differ between an ncbp mutant and a wild type plant in single cells, but viral cell-to-cell movement was significantly delayed in the ncbp mutant. Furthermore, the accumulation of triple-gene-block protein 2 (TGB2) and TGB3, the movement proteins of potexviruses, decreased in the ncbp mutant. Inoculation experiments with several viruses showed that the accumulation of viruses encoding TGBs in their genomes decreased in the ncbp mutant. These results indicate that nCBP is a novel member of the eIF4E family recessive resistance genes whose loss impairs viral cell-to-cell movement by inhibiting the efficient accumulation of TGB2 and TGB3.


Assuntos
Arabidopsis/genética , Arabidopsis/virologia , Fator de Iniciação 4E em Eucariotos/genética , Proteínas de Plantas/genética , Potexvirus/patogenicidade , Movimento Celular , Resistência à Doença , Mutação , Isoformas de Proteínas/genética , Proteínas Virais/metabolismo
18.
Front Microbiol ; 7: 1695, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27833593

RESUMO

The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant's resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF) 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species.

19.
Plant J ; 88(1): 120-131, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27402258

RESUMO

One of the plant host resistance machineries to viruses is attributed to recessive alleles of genes encoding critical host factors for virus infection. This type of resistance, also referred to as recessive resistance, is useful for revealing plant-virus interactions and for breeding antivirus resistance in crop plants. Therefore, it is important to identify a novel host factor responsible for robust recessive resistance to plant viruses. Here, we identified a mutant from an ethylmethane sulfonate (EMS)-mutagenized Arabidopsis population which confers resistance to plantago asiatica mosaic virus (PlAMV, genus Potexvirus). Based on map-based cloning and single nucleotide polymorphism analysis, we identified a premature termination codon in a functionally unknown gene containing a GYF domain, which binds to proline-rich sequences in eukaryotes. Complementation analyses and robust resistance to PlAMV in a T-DNA mutant demonstrated that this gene, named Essential for poteXvirus Accumulation 1 (EXA1), is indispensable for PlAMV infection. EXA1 contains a GYF domain and a conserved motif for interaction with eukaryotic translation initiation factor 4E (eIF4E), and is highly conserved among monocot and dicot species. Analysis using qRT-PCR and immunoblotting revealed that EXA1 was expressed in all tissues, and was not transcriptionally responsive to PlAMV infection in Arabidopsis plants. Moreover, accumulation of PlAMV and a PlAMV-derived replicon was drastically diminished in the initially infected cells by the EXA1 deficiency. Accumulation of two other potexviruses also decreased in exa1-1 mutant plants. Our results provided a functional annotation to GYF domain-containing proteins by revealing the function of the highly conserved EXA1 gene in plant-virus interactions.


Assuntos
Arabidopsis/metabolismo , Arabidopsis/virologia , Doenças das Plantas/virologia , Vírus de Plantas/patogenicidade , Arabidopsis/genética , Doenças das Plantas/genética
20.
Genome Announc ; 4(2)2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27034476

RESUMO

Hydrangea ringspot virus (HdRSV) is a plant RNA virus, naturally infectingHydrangea macrophylla Here, we report the first genomic sequences of two HdRSV isolates from hydrangea plants in Japan. The overall nucleotide sequences of these Japanese isolates were 96.0 to 96.3% identical to those of known European isolates.

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