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Here, we report a novel double-stranded RNA virus designated Colletotrichum liriopes partitivirus 1 (ClPV1) from the plant pathogenic fungus Colletotrichum liriopes. ClPV1 genome has two dsRNAs, named as dsRNA 1 and dsRNA 2, which...
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Here, we report a novel double-stranded RNA virus designated Colletotrichum liriopes partitivirus 1 (ClPV1) from the plant pathogenic fungus Colletotrichum liriopes. ClPV1 genome has two dsRNAs, named as dsRNA 1 and dsRNA 2, which in the lengths of 1807 and 1706 bp, respectively. The dsRNA 1 and dsRNA 2 encoded proteins showing significant amino acid (aa) sequence identity to the RNA-dependent RNA polymerase (RdRp) and coat protein (CP) of partitiviruses, respectively. Phylogenetic analysis using the aa sequences of RdRp and CP indicated that ClPV1 was grouped to members of the putative Epsilonpartitivirus genus in the Partitiviridae family. Spherical viral particles in approximately 35 nm in diameter and packaging the ClPV1 genome were isolated. Virus elimination and virus transfection with purified viral particles, and biological comparison revealed that ClPV1 could reduce the virulence and conidia production of C. liriopes. To the best of our knowledge, this is the first report of mycovirus in C. liriopes fungus.
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A novel double-stranded RNA (dsRNA) virus, tentatively named "Paris alphapartitivirus 1" (ParAPV1, OL960006-OL960007), was detected in Paris polyphylla var. yunnanensis plants exhibiting leaf chlorosis and shrinkage symptoms in Yu...
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A novel double-stranded RNA (dsRNA) virus, tentatively named "Paris alphapartitivirus 1" (ParAPV1, OL960006-OL960007), was detected in Paris polyphylla var. yunnanensis plants exhibiting leaf chlorosis and shrinkage symptoms in Yunnan. Its complete genome sequence was determined using Illumina and Sanger sequencing. ParAPV1 has a bipartite genome that consists of dsRNA1 (1,917 bp) encoding the viral RNA-dependent RNA polymerase (RdRp), and dsRNA2 (1,818 bp) encoding the putative coat protein (CP). Sequence comparisons showed that the RdRp and CP of ParAPV1 are most similar to those of pear alphapartitivirus (PpPV2), with 69.97% and 54.21% amino acid sequence identities respectively. Phylogenetic analysis of the RdRp amino acid sequences of ParAPV1 and other partitiviruses showed that ParAPV1 cluster with viruses in a clade containing alphapartitiviruses, and that its closest known relatives are PpPV2 (BBA66577) and rose partitivirus (RoPV, ANQ45203S). Taken together, these results suggest that ParAPV1 should be regarded as a new member of genus Alphapartitivirus in the family Partitiviridae. This is the first report of a partitivirus infecting P. polyphylla var. yunnanensis.
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Grifola frondosa (Maitake mushroom) is an important cultivated mushroom due to its medicinal and nutrient values. In this study, we isolated and characterized a novel partitivirus (named Grifola frondosa partitivirus 1, GfPV1) inf...
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Grifola frondosa (Maitake mushroom) is an important cultivated mushroom due to its medicinal and nutrient values. In this study, we isolated and characterized a novel partitivirus (named Grifola frondosa partitivirus 1, GfPV1) infecting a standard G. frondosa strain Gf-N2. This virus has a two-segmented dsRNA genome (dsRNA1 and dsRNA2) with nucleotide lengths of 2.3 and 2.2 kbp, respectively. The coding strand of dsRNA1 and dsRNA2 segments carries single open reading frame encoding RNA-dependent RNA polymerase (RdRp) and a coat protein (CP), respectively. BLAST searches and phylogenetic analyses showed that GfPV1 is most closely related to a betapartitivirus, Lentinula edodes partitivirus 1 (RdRp <70% and CP <60% amino acid sequence identities), but the sequence divergence suggests that GfPV1 is classifiable as a new member of the genus Betapartitivirus, family Partitiviridae. The presence of GfPV1 does not affect colony morphology and fruiting body development of G. frondosa. This is the first report investigating the effects of a mycovirus infection on the colony morphology and fruiting body development of G. frondosa. Interestingly, GfPV1 accumulations markedly decreased along with the fruiting body maturation stages, suggesting the inhibition of virus multiplication during sexual phase of the G. frondosa life cycle. (c) 2019 Published by Elsevier B.V. on behalf of the Mycological Society of Japan.
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Abstract Serum samples collected from 88 Peruvians with unexplained fever were analyzed for viral sequences using metagenomics. Nucleic acids of anelloviruses, pegivirus A (GBV-C), HIV, Dengue virus, and Oropouche virus were detec...
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Abstract Serum samples collected from 88 Peruvians with unexplained fever were analyzed for viral sequences using metagenomics. Nucleic acids of anelloviruses, pegivirus A (GBV-C), HIV, Dengue virus, and Oropouche virus were detected. We also characterized from two sera the RNA genomes of new species of partitivirus and dicistrovirus belonging to viral families known to infect fungi or arthropod, respectively. Genomic DNA of a putative fungal cellular?host could be PCR amplified from the partitivirus-containing serum sample. The detection in human serum of nucleic acids from viral families not known to infect vertebrates may indicate contamination during sample collection and aliquoting or human infection by their presumed cellular host, here a fungus. The role, if any, of the non-vertebrate infecting viruses detected in serum in inducing fever is unknown.
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We report here the presence of dsRNA mycoviruses in a Korean isolate of Rosellinia necatrix. A multiple band pattern of double-stranded RNA (dsRNA) from R. necatrix suggested mixed mycovirus infection. Next-generation sequencing a...
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We report here the presence of dsRNA mycoviruses in a Korean isolate of Rosellinia necatrix. A multiple band pattern of double-stranded RNA (dsRNA) from R. necatrix suggested mixed mycovirus infection. Next-generation sequencing analysis of purified dsRNAs indicated the presence of two dsRNA mycoviruses related to the members of families "Fusagraviridae" (proposed) and Partitiviridae. The first dsRNA virus revealed that the complete genome sequence was 8868 bp in size and contained two large open reading frames (ORFs 1 and 2), overlapped by 22 bp containing a canonical (- 1) slippery heptanucelotide sequence of UUUAAAC. The deduced amino acid sequence of ORF1 and ORF2 showed highest similarity to the hypothetical protein and RNA-dependent RNA polymerase (RdRp) of Rosellinia necatrix fusagravirus 3 (RnFGV3). Phylogenetic analysis showed that this dsRNA virus clustered with RnFGV3 and other fusagraviruses. Gene organization, sequence similarity, and phylogenetic analysis indicate that this virus seems to belong to a novel species of "Fusagraviridae", which we have named Rosellinia necatrix fusagravirus 4. The second virus has two dsRNA segments with sizes of 1907 bp and 1918 bp, each of which encoded a single ORF showing highest similarity to the RdRp and capsid protein of known members of Partitiviridae. Evaluation of genome structure, sequence similarity, and phylogeny indicate this to be a new member of the genus Alphapartitivirus in the family Partitiviridae, hereafter designated as Rosellinia necatrix partitivirus 26. This is the first report of the presence of a fusagravirus in an Asian R. necatrix isolate and of its mixed infection with a partitivirus.
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Quinoa (Chenopodium quinoa) is an important crop that is used as a model host for studying plant viruses. Genome sequences of five partitiviruses (two novel betapartitiviruses, two novel deltapartitiviruses, and one known gammapar...
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Quinoa (Chenopodium quinoa) is an important crop that is used as a model host for studying plant viruses. Genome sequences of five partitiviruses (two novel betapartitiviruses, two novel deltapartitiviruses, and one known gammapartitivirus) were identified from 65 quinoa transcriptome datasets. All quinoa transcriptome datasets analyzed in this study contained at least one of these partitivirus genome segments. These partitivirus sequences may affect the biology of quinoa plants or artificially infected viruses, and therefore could interfere with the accurate interpretation of the experimental results obtained from using quinoa as the host plants.
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Two double-stranded RNAs (dsRNA) likely representing the genome of a novel alphapartitivirus which we provisionally named Erysiphe palczewskii alphapartitivirus 1 (EpV1) were recovered from the powdery mildew fungus E. palczewskii...
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Two double-stranded RNAs (dsRNA) likely representing the genome of a novel alphapartitivirus which we provisionally named Erysiphe palczewskii alphapartitivirus 1 (EpV1) were recovered from the powdery mildew fungus E. palczewskii infecting Sophora japonica in Jingzhou, Hubei province of China. The two dsRNAs, 1955 (dsRNA1) and 1917 (dsRNA2) bp in size, respectively, each contains a single open reading frame (ORF) encoding a 585- and 528-aa protein, respectively. The 585-aa protein contains a conserved RNA-dependent RNA polymerase (RdRp) domain and shows significant homology to RdRps of approved or putative partitiviruses, particularly those belonging to the genus Alphapartitivirus. However, it shares an aa sequence identity lower than 80% with its closest relative, the RdRp of the putative alphapartitivirus Grapevine partitivirus, and lower than 60% with the RdRps of other partitiviruses. In a phylogenetic tree constructed with RdRp aa sequences of selected partitiviruses, the putative virus EpV1 clustered with Grapevine partitivirus and formed a well-supported monophyletic clade with known or putative alphapartitiviruses.
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Many Mediteranean isolates ofRosellinia necatrix, causing root rot in avocado, have previously been screened for viruses. Among them is isolate Rn459 that has been shown to be infected by at least three viruses such as Rosellinia ...
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Many Mediteranean isolates ofRosellinia necatrix, causing root rot in avocado, have previously been screened for viruses. Among them is isolate Rn459 that has been shown to be infected by at least three viruses such as Rosellinia necatrix partitivirus 10 (RnPV10), Rosellinia necatrix hypovirus 2 (RnHV2), Rosellinia necatrix fusagravirus 1 (RnFGV1), and Rosellinia necatrix virga-like virus (RnVLV). Here, we attempted to eliminate the viruses by hyphal tip cultures to examine their effect on colony growth in vitro and virulence on avocado plants. The obtained fungal strain termed, Rn459_PV10F/VLVF, which was confirmed to be cured of RnPV10 and RnVLV, but still retaining RnHV2, manifested a phenotype different from the original Rn459. Colony growth comparison showed that Rn459_PV10F/VLVF grew faster than the original Rn459 isolate and the virulence on avocado plants of this Rn459_PV10F/VLVF strain was higher than the original Rn459 strain. These combined results suggest that RnPV10 and RnVLV, alone or together, contribute to confer hypovirulence on theR. necatrixisolates.
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Since the 1970s, several dsRNA viruses, including Radish yellow edge virus, Raphanus sativus virus 1, Raphanus sativus virus 2, and Raphanus sativus virus 3, have been identified and reported as infecting radish. In the present st...
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Since the 1970s, several dsRNA viruses, including Radish yellow edge virus, Raphanus sativus virus 1, Raphanus sativus virus 2, and Raphanus sativus virus 3, have been identified and reported as infecting radish. In the present study, in conjunction with a survey of seed-borne viruses in cultivated Brassica and Raphanus using the dsRNA diagnostic method, we discovered 3 novel cryptoviruses that infect Brassica and Raphanus: Raphanus sativus partitivirus 1, which infects radish (Raphanus sativus); Sinapis alba cryptic virus 1, which infects Sinapis alba; and Brassica rapa cryptic virus 1 (BrCV1), which infects Brassica rapa. The genomic organization of these cryptoviruses was analyzed and characterized. BrCV1 might represent the first plant partitivirus found in Gammapartitivirus. Additionally, the evolutionary relationships among all of the partitiviruses reported in Raphanus and Brassica were analyzed.
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Ash trees (Fraxinus spp.) are widely distributed through European, Asian, and North American temperate zones. There are numerous recently identified pests and pathogens that have killed hundreds of millions of ash worldwide. In 20...
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Ash trees (Fraxinus spp.) are widely distributed through European, Asian, and North American temperate zones. There are numerous recently identified pests and pathogens that have killed hundreds of millions of ash worldwide. In 2014, white ash trees in Colorado exhibited symptoms of chlorotic patches that increased in size through the growing season and developed necrotic lesions. Partially purified extracts of symptomatic leaves examined by transmission electron microscopy identified spherical virus-like particles. Next generation RNA sequencing of symptomatic tissue identified five virus-like contigs with similarity to both partitiviruses and caulimoviruses. Primers designed from the putative contigs amplified products of the expected size from both inoculated plants and wild ash seedlings. Further work is required to complete the virus genomes, phylogenetic analysis, complete Koch's postulates, and determine the distribution of these viruses in the Fraxinus genus.
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