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1.
Arch Virol ; 167(2): 631-634, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35028739

RESUMO

The complete genome sequences of two isolates of spiraea yellow leafspot virus (SYLSV) were determined. Spiraea (Spiraea x bumalda) 'Anthony Waterer' plants showing virus-like symptoms including yellow spotting and leaf deformation were used for sequencing. The viral genome of SYLSV-MN (Minnesota) and SYLSV-MD (Maryland) is 8,017bp in length. The sequences share 95% identity at the nucleotide level. Both isolates have the same genome organization containing three open reading frames (ORFs), with ORF3 being the largest, encoding a putative polyprotein of 232 kDa with conserved domains including a zinc finger, pepsin-like aspartate protease, reverse transcriptase (RT), and RNase H. Pairwise comparisons between members of the genus Badnavirus showed that gooseberry vein banding associated virus GB1 (HQ852248) and rubus yellow net virus isolate Baumforth's Seedling A (KM078034) were the closest related virus sequences to SYLSV, sharing 73% identity at the nucleotide level. Bacilliform virions with dimensions of 150 nm × 30 nm were observed in virus preparations from symptomatic, but not asymptomatic, plants.


Assuntos
Badnavirus , Spiraea , Badnavirus/genética , Genoma Viral , Fases de Leitura Aberta , Filogenia , Doenças das Plantas
2.
Arch Virol ; 165(7): 1671-1673, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32335770

RESUMO

A previously undescribed badnavirus was isolated from Zamia fischeri showing symptoms of chlorosis, necrosis, and ringspot. The virus has bacilliform virions 30 nm in diameter and averaging 120 nm in length. The viral genome is 9227 bp in length and contains three open reading frames characteristic of members of the genus Badnavirus. The largest open reading frame (ORF3) encodes a putative polyprotein, with predicted domains including zinc finger, aspartic protease, reverse transcriptase (RT) and RNase H. The virus is tentatively named "cycad leaf necrosis virus" (CLNV). Within the genus Badnavirus, CLNV was most closely related to sugarcane bacilliform Guadeloupe D virus (FJ439817), sharing 69% identity at the nucleotide level in the RT + RNase H region. This virus is the first badnavirus reported to infect cycads, and it has the largest genome among the currently characterized badnaviruses.


Assuntos
Badnavirus/genética , Cycadopsida/virologia , Genoma Viral , Badnavirus/classificação , Badnavirus/isolamento & purificação , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/virologia , Proteínas Virais/genética
3.
Arch Virol ; 165(1): 237-239, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31679082

RESUMO

Aglaonema bacilliform virus (ABV), a member of the genus Badnavirus in the family Caulimoviridae, is associated with leaf deformation and chlorosis in Aglaonema modestum. The complete genome sequence of a Minnesota isolate of ABV was determined. The ABV genome is 7,178 bp in length and similar in size and organization to those of the members of the genus Badnavirus, containing three open reading frames (ORFs) with the potential to encode three proteins of 14.92, 13.33 and 207.95 kDa, respectively. The last ORF (ORF3) encodes a putative polyprotein with conserved domains, including zinc finger, aspartic protease, reverse transcriptase (RT) and RNase H domains, in that order. Phylogenetic analysis using the amino acid sequence of the ORF3 polyprotein showed that ABV clusters with several isolates of taro bacilliform CH virus (TaBCHV). Pairwise alignment using the highly conserved RT/RNase H region reveals that ABV has the highest level of identity (71%) at the nucleotide level to a Hawaiian isolate of TaBCHV.


Assuntos
Badnavirus/genética , Sequenciamento Completo do Genoma/métodos , Badnavirus/classificação , Tamanho do Genoma , Genoma Viral , Fases de Leitura Aberta , Filogenia
4.
Arch Virol ; 164(9): 2371-2374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31165927

RESUMO

A previously undescribed badnavirus was identified in plants of Polyscias fruticosa (Ming aralia) showing symptoms of mild mosaic and leaf senescence. Characteristic bacilliform virions of the Polyscias badnavirus averaging 30 × 120 nm in size were observed by transmission electron microscopy in partially purified leaf tissue extracts from symptomatic but not asymptomatic plants collected in the USA and Nigeria. The isolate from the USA was complete sequenced. The genome is 7592 bp in length and contains three open reading frames with an arrangement similar to that of other members of the genus Badnavirus. The largest open reading frame (ORF3) encodes a putative polyprotein, with predicted domains including zinc finger, aspartic protease, reverse transcriptase (RT) and RNase H, in that order. The USA and Nigeria isolates of the virus had a high level (98%) of nucleotide sequence identity in the RT+RNase H region. Within the genus Badnavirus, these viruses were most closely related to schefflera ringspot virus (SRV), sharing 63% identity at the nucleotide level. Based on the ICTV species demarcation criteria for the genus Badnavirus (more than 20% nucleotide sequence divergence in the RT+RNase H region), the Polyscias virus is proposed to be a new member of the genus, and the name polyscias mosaic virus (PoMV) is proposed. The complete genome sequence was deposited in the NCBI GenBank database under accession no. MH475918.


Assuntos
Araliaceae/virologia , Badnavirus/isolamento & purificação , Genoma Viral , Doenças das Plantas/virologia , Badnavirus/classificação , Badnavirus/genética , Sequência de Bases , Dados de Sequência Molecular , Nigéria , Fases de Leitura Aberta , Filogenia , Folhas de Planta/virologia , Sequenciamento Completo do Genoma
5.
Cancer Chemother Pharmacol ; 83(4): 743-753, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30684019

RESUMO

PURPOSE: The primary objective of this multicentric dose allocation and dose expansion study was to determine the MTD and the DLTs of the lucitanib (a tyrosine kinase inhibitor of the FGFR/VEGFR/PDFGR pathways)/fulvestrant combination. METHODS: Postmenopausal women with ER+/HER2- mBC, who have relapsed during or after treatment with fulvestrant, were eligible. The study had a dose allocation part to assess the tolerability of the combination followed by a dose expansion part. RESULTS: Eighteen patients with ER+, mBC were enrolled; median age was 66 years, 50% had a PS: 0 and all had received previous endocrine treatment. The study was prematurely terminated after 18 patients (15 in part 1 and 3 in part 2) based on preclinical experiments that failed to confirm the hypothesis that addition of lucitanib would reverse sensitivity to endocrine treatments. Based on data of global lucitanib development, it was decided to stop the dose allocation at 12.5 mg and to start the dose expansion part at 10 mg/day. The most common grade ≥ 3 toxicities (> 10% of patients) were hypertension (78%) and asthenia (22%). All patients required at ≥ 1 interruption, 13 patients (72%) required ≥ 1 dose reduction. Three patients (72%) withdrew from the study for AEs (at 10 mg). Three patients achieved a confirmed PR (10 mg n = 1; 12.5 mg n = 2). CONCLUSION: Although the combination is feasible it requires close monitoring of the patients for the management of adverse events. Further investigation is required to better understand the potential role of FGFR inhibition in reversing resistance to endocrine treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores de Estrogênio/metabolismo , Administração Oral , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Relação Dose-Resposta a Droga , Feminino , Fulvestranto/administração & dosagem , Humanos , Dose Máxima Tolerável , Pessoa de Meia-Idade , Naftalenos/administração & dosagem , Metástase Neoplásica , Pós-Menopausa , Quinolinas/administração & dosagem
6.
Plant Dis ; 100(4): 696-703, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30688604

RESUMO

Cranberry plants bearing disfigured, scarred fruit were reported by growers in the major cranberry-growing region of central Wisconsin in July 2012. Plants bearing scarred fruit have since been observed in Massachusetts and New Jersey. Three complementary methods provided evidence of Tobacco streak virus (TSV) in symptomatic plants: (i) leaves and scarred berries tested positive for TSV by double-antibody sandwich enzyme-linked immunosorbent assay; (ii) quasi-isometric particles approximately 33 nm in diameter were extracted from leaves of symptomatic plants and visualized using transmission electron microscopy; and (iii) coat protein gene sequence analysis revealed 94 to 99% nucleotide similarity with reference TSV sequences. In newer cultivars, 99% of uprights with scarred berries tested positive for TSV. In older cultivars, 31% of uprights with scarred berries tested positive for TSV and the remaining 69% of uprights with scarred berries tested positive for Blueberry shock virus. TSV overwintered in cranberry plants, and leaves, pollen, and fruit tested positive for TSV the year following symptom occurrence. Attempts to inoculate cranberry using infected pollen or sap as inoculum failed, but several herbaceous hosts tested TSV positive following mechanical inoculation. Phylogenetic analysis of the coat protein gene of 26 TSV isolates from various cultivars of cranberry in Wisconsin, New Jersey, and Massachusetts revealed diversity. This work provides information that will be useful in understanding the epidemiology of TSV in cranberry and in the development of management strategies.

7.
Plant Dis ; 99(3): 422, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30699714

RESUMO

Pachysandra terminalis Siebold & Zucc. (Japanese pachysandra, spurge) is widely used as a groundcover. In early 2012, Japanese pachysandra plants from Missouri, which originated in Pennsylvania, showed symptoms of light and dark green mosaic, leaf deformation, concentric ringspots, and stunting. Initial screening of symptomatic leaf tissue by transmission electron microscopy (TEM) using partially purified extracts confirmed the presence of spherical (~28 nm) and bacilliform (18-nm diameter, 35- to 58-nm length) virus particles. Immunosorbent electron microscopy (ISEM) using antisera to a clover isolate of Alfalfa mosaic virus (AMV) (PVAS 92) and to Cucumber mosaic virus (CMV) (ATCC PVAS-30) obtained from the American Type Culture Collection, Manassas, VA, confirmed the presence of AMV and CMV. No other type of virus-like particles were observed by TEM. After 6 months, nearly 20% of the 4,000 pachysandra cuttings exhibited the described symptoms. However, it is possible that more than 20% of the cuttings were infected with both viruses and not yet exhibiting symptoms. Reverse-transcription PCR (RT-PCR) was done using total RNA extracted with a Qiagen RNeasy kit and Ready-To-Go RT-PCR beads (GE Healthcare, UK Limited, UK). The primer pair CMV-1 (5'-GCCGTAAGCTGGATGGACCA) and CMV-2 (5'-TATGATAAGAAGCTTGTTTTCGCG) were used (3) to obtain a 502-bp amplicon from the coat protein (CP) region of CMV RNA 3. The product was ligated and cloned (pGEM-T Easy Vector System; Promega, USA). Three clones were sequenced (UMGC, USA), and the consensus sequence (Sequencher 5.1, Gene Codes Corp., USA) was deposited in GenBank (Accession No. JX227938). The sequence obtained had 100% identity with a homologous CP CMV sequence (AFQ94058) and 99% identity with several other homologous CP CMV sequences (CAX62443, CCK24369, and 15 others). It also contained an EcoRI site at nucleotides 332 to 337, characteristic of CMV Type II isolates (3). The primer pair AMV1F (5'-ATCCACCGATGCCAGCCTTA) and AMV1R (5'-TTCCGCCTCACTGCTGCTG) generated a 1,047-bp product from AMV RNA1 that was deposited in GenBank (JX227937). This product had 100% identity with a homologous AMV sequence (AFQ94057), and 99% identity with several other homologous AMV sequences (AGV15824, ADO85715, CBX36144). From the data presented here, it was concluded that the pachysandra had a mixed infection of AMV and a Type II isolate of CMV. Occurrence of AMV in pachysandra was first reported in New Jersey in 1982 (2) and reported for the first time in France and Germany in 2000 (1). The presence of CMV infection in pachysandra has not been reported in the present literature. Some of the symptoms associated with AMV infection in pachysandra in New Jersey (2) and Europe (1) were similar to the symptoms produced by pachysandra plants infected with both viruses (ring spots, mosaic, and line patterns). However, some symptoms were unique to the mixed infection in pachysandra by AMV and CMV (leaf deformation, stunting). A potential source of this co-infection could occur when plants are grown near alfalfa fields (AMV infection by aphids) and undergo vegetative propagation (CMV infection by contaminated tools). This is the first report of pachysandra co-infected by AMV and CMV in the United States. References: (1) L. Cardin and B. Moury. Plant Dis. 84:594, 2000. (2) D. E. Hershman and E. H. Varney. Plant Dis. 66:1195, 1982. (3) S. Wylie et al. Aust. J. Agric. Res. 44:41, 1993.

8.
Plant Dis ; 99(1): 165, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30699771

RESUMO

Mandevilla (Apocynaceae) is an ornamental tropical vine popular for its bright and attractive flowers. During 2012 to 2013, 12 Mandevilla sp. samples from Minnesota and Florida nurseries were submitted for analysis at the University of Minnesota Plant Disease Clinic. Plants showed mosaic symptoms, leaf deformation, premature leaf senescence, and vine dieback. Filamentous virus particles with modal lengths 700 to 900 nm were observed by transmission electron microscopy (TEM) in partially purified preparations from symptomatic leaves. Partially purified virions were obtained using 30% sucrose cushion centrifuged at 109,000 gmax for 2 h at 10°C (5). No other virus particles were observed in these samples, nor were any observed in non-symptomatic samples. One sample was submitted as potted plant (Mandevilla 'Sunmandeho' Sun Parasol Giant White) and was kept under greenhouse conditions for subsequent analyses. Total RNA (Qiagen) was extracted from this sample, and Potyvirus was detected using the universal primers Poty S (5'-GGN AAY AAY AGY GGN CAR CC-3') and PV1 (5'-20(T)V-3') (1) by reverse transcription (RT)-PCR (3). The amplified product was the expected ~1.7-kb, corresponding to the partial nuclear inclusion body gene, the coat protein (CP) gene, and the 3' end untranslated region. The RT-PCR amplicon was cloned (NEB) and sequenced, and the 1,720-bp consensus sequence was deposited in GenBank (Accession No. KM243928). NCBI BLAST analysis at the nucleotide level revealed highest identity (83%) with an isolate of Catharanthus mosaic virus (CatMV) from Brazil (Accession No. DQ365928). Pairwise analysis of the predicted 256 amino acid CP revealed 91% identity with the CatMV Brazilian isolate (ABI94824) and 68% or less identity with other potyviruses. Two potyviruses are usually considered the same species if their CP amino acid sequences are greater than 80% identical (2). Serological analysis of the infected sample Mandevilla 'Sunmandeho' Sun Parasol Giant White using a CatMV specific antiserum (4) resulted in positive indirect ELISA reactions. CatMV has been previously reported in periwinkle (Catharanthus roseus) in Brazil (4). Based on the analyses by TEM, RT-PCR, nucleotide and amino acid sequence identities, and serological reactivity, we identify this virus as a U.S. Mandevilla isolate of CatMV. To our knowledge, this is the first report of Catharanthus mosaic virus both in the United States and in Mandevilla. References: (1) J. Chen et al. Arch Virol. 146:757, 2001. (2) A. Gibbs and K. Ohshima. Ann. Rev. Phytopathol. 48:205, 2010. (3) R. L. Jordan et al. Acta Hortic. 901:159, 2011. (4) S. C. Maciell et al. Sci. Agric. Piracicaba, Brazil. 68:687, 2011. (5) D. Mollov et al. Arch Virol. 158:1917, 2013.

9.
Plant Dis ; 98(3): 419, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30708421

RESUMO

During the growing season of 2012, 35 garlic plant samples were submitted to the University of Minnesota Plant Disease Clinic for disease diagnosis. Samples originated from multiple counties throughout Minnesota as well as Iowa, Wisconsin, and South Dakota. Symptoms first appeared at the time plants were starting to produce scapes. Symptoms included leaf discoloration that varied from yellow to purple, plant stunting, and leaf tip necrosis. In severe cases, the plants wilted and died. Bulbs of affected plants ranged from being soft and small to almost normal-looking. Symptoms were similar to those associated with phytoplasma infection in other plants. Total genomic DNA was extracted from 30 symptomatic samples and five asymptomatic leaf samples using a Qiagen DNeasy Plant Mini Kit (Qiagen, Germantown, MD) according to the manufacturer's instructions, and used with the universal phytoplasma primers P1/P7 in a direct PCR assay, and with P1/AYint in a nested PCR assay (2) to yield amplicons of 1.8 and 1.6 kb, respectively. Asymptomatic plants did not produce amplicons. Garlic cultivars displaying a range of symptoms tested positive for the presence of phytoplasma. These cultivars included: Susanville, Middle Eastern, Music, Ajo Rojo, Spanish Roja, Inchelium Red, Silver White, Asian Tempest, Chesnok Red, and Purple Glazer. The P1/P7 PCR products of 1,830 bp were purified using the PureLink PCR Purification kit (Life Technologies, Carlsbad, CA), and cloned in a pGem T-Easy vector system (Promega, Madison, WI). Sequences from a clone from each of Wisconsin, Iowa, and Minnesota were deposited in GenBank under the accession numbers KC000005, KC000006, and KC000007, respectively. A BLASTn similarity search revealed that the Wisconsin and Iowa isolates shared 99% homology to the sequences of 16SrI-A group phytoplasmas, aster yellows phytoplasma (AY389827), and aconitum proliferation phytoplasma (AF510323). The Minnesota isolate had 99% sequence homology to a 16SrI-B group phytoplasma, mulberry yellow dwarf phytoplasma (GQ249410). Also, the iPhyClassifier 16Sr group/subgroup classification based on similarity (3) analyses showed that the Wisconsin and Iowa phytoplasma isolates had 16S rDNA sequences in the 16SrI-A group with similarity coefficients of 0.97 and 1.00, respectively, to aster yellows witches'-broom phytoplasma AYWB (NC_007716). The same analysis revealed that the Minnesota phytoplasma isolate 16S rDNA sequence grouped with the 16SrI-B group onion yellows phytoplasma (NC_005303) with a similarity coefficient of 1.0. A phylogenic tree was deduced by the neighbor joining algorithm, clustering together the Iowa, Minnesota, and Wisconsin isolate sequences with a 16SrI group phytoplasma. Aster yellows phytoplasma has been reported in North America, but only in Canada (1). This is the first documented occurrence of 16SrI aster yellows group phytoplasma in garlic in the United States. The spring of 2012 was unusually warm, and high leafhopper pressure was observed throughout the Midwest; above average numbers of many ornamental crops and small grains were infected with phytoplasma. These events may have contributed to the phytoplasma infection in garlic. References: (1) A. H. Khadhair et al. Microbiol. Res. 157:161, 2002. (2) C. D. Smart et al. Appl. Env. Microbiol. 62:2988, 1996. (3) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

10.
Plant Dis ; 97(9): 1258, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30722405

RESUMO

In spring of 2012, a previously unrecorded virus-like disease characterized by conspicuous yellow leaf blotching (calico symptoms) was observed in plants of Hydrangea macrophylla in a single location in Southampton, NY. Bacilliform and spherical particles resembling those of Alfalfa mosaic virus (AMV) were observed by transmission electron microscopy (TEM) in partially purified extracts from symptomatic leaf tissue. The identity of the virus was confirmed by immunosorbent electron microscopy (ISEM) (4) using antiserum to AMV (ATCC PVAS 92) that both trapped and decorated the virions. Three primer pairs designed from available AMV RNA 1, RNA 2, and RNA 3 genomic sequences were used to generate amplicons from the hydrangea AMV isolate. Reverse-transcription (RT)-PCR was done using total RNA extracted from symptomatic hydrangea leaf tissue with a Qiagen RNeasy kit, and Ready-to-Go RT-PCR beads (GE Healthcare). Amplicons of 1,049, 1,013, and 658 bp were obtained using the primer pairs AMV1F (5'-ATCCACCGATGCCAGCCTTA)/AMV1R (5'-TTCCGCCTCACTGCTGTCTG), AMV2F (5'-GATCGCCGGAAGTGATCCAG)/AMV2R (5'-TCACCGGAAGCAACAACGAA), and AMV3F (5'-GCCGGTTCTCCAAAGGGTCT)/AMV3R (5'-CGCGTCGAAGTCCAGACAGA), respectively. The PCR products were cloned using a TOPO TA cloning kit (Invitrogen) and three clones of each were sequenced. The sequences obtained from the hydrangea AMV RNA 1 (JX154090), RNA 2 (JX154091), and RNA 3 (JX154092) had 95 to 98% nucleotide sequence identity to homologous genomic sequences of known AMV isolates. To our knowledge, this is the first report of AMV occurrence in H. macrophylla in the United States. This virus has been reported to occur in H. macrophylla in British Columbia (3), but in a previous survey its presence was not detected in hydrangeas in the United States (1). A report of possible AMV infection in H. macrophylla in Italy (2) was based solely on symptomatology and cross-protection tests and therefore cannot be verified. The AMV-infected hydrangea plants were found by ISEM to also contain low concentrations of Hydrangea ringspot virus (HRSV) and Hydrangea chlorotic mottle virus (HdCMV). However, based on previous evidence of single and mixed infections (3), it is unlikely that the calico symptoms observed were influenced by the presence of HRSV and HdCMV. This report is of interest both because AMV, unlike HRSV and HdCMV, causes foliar symptoms that would render hydrangea plant unmarketable, and because the disease can be spread by a number of common aphid species that transmit AMV. It will also serve to alert growers and diagnosticians to the potential threat posed by AMV infection. References: (1) T. C. Allen et al. Acta Hortic. 164:85, 1985. (2) G. Belli. Phytopathol. Mediterr. 7:70, 1968. (3) A. W. Chiko and S. E. Godkin. Plant Dis. 70:541, 1986. (4) B. E. L. Lockhart et al. Phytopathology 82:691, 1992.

11.
Plant Dis ; 97(10): 1389, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30722129

RESUMO

Ornamental flower bulbs (including true bulbs, bulbils, corms, tubers, and rhizomes) are increasingly important floriculture crops. Amaryllis is a small genus of flowering bulbs, with two species. The South African native, Amaryllis belladonna, also known as belladonna lily, Jersey lily, naked lady, Amarillo, or March lily, is one of numerous ornamental species with the common name "lily" due to their flower shape and growth habit. Amaryllis are popular for their 6- to 10-inch trumpet shaped colorful flowers that are borne on 1- to 2-foot stalks. In January, 2011, a home gardener in California observed mosaic symptoms on the leaves of A. belladonna growing in her garden. Leaf samples were sent to Agdia Inc. for testing. Samples tested positive for the presence of Potyvirus in a reverse transcription (RT)-PCR screen using universal potyvirus primers (2) yielding the expected ∼1,600-bp product corresponding to the partial nuclear inclusion body (NIb) gene, full-length coat protein (CP) gene, and 3' end untranslated region (UTR). Electron microscopy of symptomatic leaves confirmed the presence of filamentous potyvirus-like particles. The RT-PCR amplicon was cloned and sequenced (2); the 1,616-bp consensus sequence was deposited in GenBank (Accession No. JX865782). NCBI BLAST analysis of the consensus sequence revealed highest identities with isolates of Nerine yellow stripe virus (NeYSV; family Potyviridae, genus Potyvirus). Pair-wise analyses of the 261 amino acid sequence of the predicted CP had 88% sequence identity with a Stenomesson isolate reported from the Netherlands (EU042758); 87% identity with Hymenocallis and Nerine isolates, both also from the Netherlands (EF362622 and EF362621, respectively); and, 86% with two New Zealand isolates infecting Amaryllis or Vallota (FJ618537 and DQ407932, respectively). The five Netherlands and New Zealand isolates are more closely related to each other than to the U.S. isolate as they share 93 to 98% CP identity. When using viral genome sequence relatedness as a criterion for defining potyvirus species, isolates with CP amino acid identity greater than 80% are considered the same species (1). The predicted coat protein gene of the California isolate was sub-cloned into the bacterial expression vector pET44 EK/LIC. Serological analysis of coat protein expressing clones in ELISA and Western Blot analysis using a potyvirus broad-spectrum reacting monoclonal antibody PTY-2 (3) and a NeYSV-specific rabbit antiserum (Applied Plant Research, Lisse, The Netherlands) resulted in positive reactions. NeYSV has previously been reported in the United Kingdom, the Netherlands, Australia, and New Zealand. Based on the results of electron microscopy, RT-PCR, nucleotide and amino acid identity, and serological reactivity, we identify this virus as a U.S. isolate of NeYSV, NeYSV-US. To our knowledge, this is the first report of Nerine yellow stripe virus in the United States. Development of antisera specific to this U.S. isolate is in progress. References: (1) A. Gibbs and K. Ohshima. Ann. Rev. Phytopathol. 48:205, 2010. (2) R. L. Jordan et al. Acta Hortic. 901:159, 2011. (3) R. L. Jordan and J. Hammond. J. Gen. Virol. 72:1531, 1991.

12.
J Nutrigenet Nutrigenomics ; 4(3): 154-64, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21757924

RESUMO

BACKGROUND: Aging and obesity induce complex transcriptomic changes in the liver, promoting the development of insulin resistance and type 2 diabetes. In spite of an increasing amount of studies on the role of aging and nutrient excess in metabolic disorders, the specific molecular events leading to insulin resistance are still poorly understood. METHODS: This study presents a comparative analysis of hepatic gene expression profiles between young adult C57BL/6J mice fed with a low- or a high-fat diet for 1 and 12 months. We evaluated the expression of a defined set of genes implicated in glucose and lipid metabolism as well as key nuclear receptors and their target genes, IGF1 signaling and clock genes. RESULTS: Aging and short-term high-fat consumption induced insulin resistance, albeit through two distinct processes. Hepatic gene expression changes were more pronounced in the context of aging. We further analyzed expression profiles together with plasma parameters by principal component analysis with regard to diet condition. CONCLUSIONS: Our results suggest that in the liver of C57BL/6J mice, the molecular mechanisms underlying high-fat feeding or aging which mediated insulin resistance were not identical.


Assuntos
Adaptação Fisiológica , Envelhecimento/genética , Perfilação da Expressão Gênica , Fígado/metabolismo , Obesidade/genética , Animais , Dieta , Fígado/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Plant Dis ; 94(7): 921, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30743575

RESUMO

Virus-like disease symptoms consisting of foliar and veinal necrosis similar to those caused by Coleus vein necrosis virus (CVNV) (2) were observed in plants of coleus (Coleus blume Benth.) 'Rustic Orange' obtained from retail greenhouse outlets in Missouri and Minnesota. Flexuous, filamentous, 750 to 770 nm virus-like particles (vlps) were observed by transmission electron microscopy in negatively stained partially purified leaf tissue extracts from symptomatic 'Rustic Orange' leaf tissue. No other virus-like particles were observed and none were detected in extracts from asymptomatic leaves. These vlps were longer than those of CVNV (640 nm) (2) and were not detected by immunosorbent electron microscopy (ISEM) using antibodies to CVNV (2). Degenerate potyvirus primers PNIbF1 (5'GGBAAYAATAGTGGNCAACC3') and PCPR1 (5'GGGGAGGTGCCGTTCTCDATRCACCA3') (1) and total RNA extracted from 'Rustic Orange' leaf tissue with a Qiagen RNeasy Kit were used for reverse transcription-PCR with Ready-To-Go RT-PCR Beads (GE Healthcare). A 950-bp amplicon was obtained from total RNA from diseased but not from healthy leaf tissue. The nucleotide sequence of the amplicon (GenBank Accession No. GQ268818) had levels of identity to published Tobacco etch virus (TEV) sequences comprising portions of the nuclear inclusion body (NIb) and coat protein (CP) gene regions ranging from 89% (L38714) to 93% (M15239, M11458). The identity of the virus occurring in 'Rustic Orange' was further confirmed by ISEM. Virions were trapped and decorated by antibodies to TEV (ATCC PVAS 32). Systemically infected leaf tissue from Datura stramonium in which the coleus TEV isolate was propagated was used to mechanically inoculate Carborundum-dusted leaves of virus-free test plants of 'Rustic Orange' (Park Seed, Greenwood, SC). Inoculated plants developed foliar necrosis symptoms similar to those observed originally, and the presence of TEV was confirmed by ISEM and RT-PCR and nucleotide sequence analysis as described above. To our knowledge, this is the first report of a disease of coleus caused by TEV. Many of approximately 30 'Rustic Orange' plants in one nursery in Minnesota showed similar necrotic foliar symptoms and randomly selected plants tested positive for TEV by ISEM. This suggests that TEV infection in this variety may be spread by vegetative propagation from infected stock plants. References: (1) Y.-C. Hsu et al. J. Virol. Methods 128:54. 2005. (2) D. S. Mollov et al. Plant Dis. 91:754. 2007.

14.
Plant Dis ; 94(3): 374, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30754214

RESUMO

Sedums (Sedum spp.; Crassulaceae) are perennial landscape plants that are grown widely because they are drought tolerant and winter hardy. Plants of Sedum 'Matrona' showing faint foliar ringspot symptoms were collected at a nursery retail outlet in St. Paul, MN in July 2008 and tested for possible viral infection by transmission electron microscopic (TEM) examination of negatively stained, partially purified leaf tissue extracts (1). The only virus-like particles observed were rigid, rod-shaped particles similar to those of Tobacco rattle virus (TRV) and other tobraviruses. A random sample of 100 measurements showed particles 20 nm in diameter with two modal lengths of 115 nm and 175 nm. These virus-like particles were confirmed to be those of TRV by immunosorbent electron microscopy (1) using antiserum to TRV (ATCC PVAS 75) and by reverse transcription (RT)-PCR using total RNA extracted with the RNeasy Kit (Qiagen, Valencia, CA) and primers that yield a 462-bp amplicon from TRV RNA 1 (4). An amplicon of the expected size was obtained by RT-PCR and its nucleotide sequence (GenBank Accession No. GQ268817) had 95 to 99% identity to published TRV sequences (AAW13192 and AAB48382). Two additional amplicons generated by RT-PCR from separate plants were identical in size and nucleotide sequence to the first. On the basis of virion morphology, serological relatedness, and sequence identity, the virus associated with mild ringspot symptoms in sedum was identified as an isolate of TRV. To our knowledge, this represents the first report of TRV incidence in sedum. Although Arabis mosaic virus is the only other virus reported to occur in sedum (2), we have observed numerous, flexuous filamentous 750 to 800 nm virus-like particles in partially purified extracts of a range of sedums showing mild mosaic and/or vein-clearing symptoms in Minnesota. Similar virus-like particles were not observed by TEM in partially purified extracts from TRV-infected 'Matrona' plants, suggesting that they did not contribute to the symptoms observed. We have reported previously (3) the occurrence of TRV in a variety of widely grown perennial ornamentals that provide potential sources of inoculum for spread of this virus by nematode vectors (Trichodorus and Paratrichodorus spp.) that occur commonly in garden soil, and Sedum is now added to the list of potential TRV reservoir plants. References: (1) Y. S. Ahlawat et al. Plant Dis. 80:590, 1996. (2) A. Gera et al. Acta Hortic. 722:175, 2006. (3) B. E. Lockhart et al. Plant Dis. 79:1249, 1995. (4) D. J. Robinson. J. Virol. Methods 40:57, 1992.

16.
Plant Dis ; 92(10): 1473, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30769547

RESUMO

Stunting, chlorosis, and light yellow mottling resembling symptoms of nutrient deficiency were observed in angelonia (Angelonia angustifolia) in commercial production in New York. Numerous, filamentous particles 520 to 540 nm long and spherical virus particles 30 nm in diameter were observed by transmission electron microscopy (TEM) in negatively stained partially purified extracts of symptomatic Angelonia leaf tissue. Two viruses, the filamentous potexvirus Alternanthera mosaic virus (AltMV) and the spherical carmovirus Angelonia flower break virus (AnFBV) were subsequently identified on the basis of nucleotide sequence analysis of amplicons generated by reverse transcription (RT)-PCR using total RNA isolated from infected leaf tissue. A 584-bp portion of the replicase-encoding region of the AltMV genome was obtained with the degenerate primers Potex 2RC (5'-AGC ATR GNN SCR TCY TG-3') and Potex 5 (5'-CAY CAR CAR GCM AAR GAT GA-3') (3). Forward (AnFBV CP 1F-5'-AGC CTG GCA ATC TGC GTA CTG ATA-3') and reverse (AnFBV CP 1R-5'-AAT ACC GCC CTC CTG TTT GGA AGT-3') primers based on the published AnFBV genomic sequence (GenBank Accession No. NC_007733) were used to amplify a portion of the viral coat protein (CP) gene. The nucleotide sequence of the amplicon generated using the potexvirus-specific primers (GenBank Accession No. EU679362) was 99% identical to the published AltMV (GenBank Accession No. NC_007731) sequence and the nucleotide sequence of the amplicon obtained using the AnFBV CP primers was 99% identical to the published AnFBV genomic sequence (GenBank Accession No. EU679363). AnFBV occurs widely in angelonia (1) and AltMV has been identified in phlox (2). These data confirm the presence of AltMV and AnFBV in diseased angelonia plants showing stunting and nutrient deficiency-like symptoms and substantiates, to our knowledge, this first report of AltMV in angelonia in the United States. References: (1) S. Adkins et al. Phytopathology 96:460, 2006. (2) J. Hammond et al. Arch. Virol. 151:477, 2006. (3) R. A. A. van der Vlugt and M. Berendeson. Eur. J. Plant Pathol. 108:367, 2002.

17.
Arch Virol ; 152(7): 1409-16, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17431738

RESUMO

An isolate of banana streak virus (BSV) that does not also occur as an integrant in the Musa balbisiana genome was sought in order to investigate the biological role of BSV in the evolution of either the Musa genome or of the virus itself. We isolated BSV virions from a Musa acuminata siamea accession from Vietnam and sequenced the entire viral genome. The molecular organization is similar to that described for other BSV but slightly larger (7801 bp vs. 1611-7568 bp), and ORF I has a non-conventional start codon. This genome was sufficiently different to propose it as a member of a distinct species named Banana streak virus strain acuminata Vietnam (BSAcVNV).


Assuntos
Badnavirus/genética , Musa/virologia , Sequência de Aminoácidos , Badnavirus/classificação , Badnavirus/isolamento & purificação , Sequência de Bases , Primers do DNA/genética , DNA Viral/genética , Genoma Viral , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Doenças das Plantas/virologia , RNA Viral/química , RNA Viral/genética , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
18.
Plant Dis ; 91(7): 906, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30780408

RESUMO

In October of 2005, a field survey was done in the province of Piura in northern Peru to determine the cause of a disease known locally as "mosaico" that was affecting organic Cavendish banana (Musa AAA) grown for the export market. Disease symptoms consisted of pronounced chlorotic and necrotic lesions on leaves of affected plants. Twenty-four farms were visited, and at each location, 10 randomly selected plants at flowering stage were evaluated for disease incidence and severity. Plants showing virus-like symptoms were observed in 18 of the 24 locations (75%). Fifty-two banana leaf samples, 27 from plants showing virus-like symptoms and 25 from asymptomatic plants, were tested for the presence of Banana streak virus (BSV), Cucumber mosaic virus (CMV), and Banana mild mosaic virus (BanMMV) by immunosorbent electron microscopy (ISEM) using partially purified leaf tissue extracts (2).The same extracts were also tested by immunocapture PCR (IC-PCR) for presence of BSV and specific BSV isolates (BSV-OL, BSV-GF, BSV-IM, and BSV-CAV) using badnavirus-specific degenerate primers and BSV isolate-specific primers, respectively (1). Seventeen of 27 leaf samples showing virus-like symptoms (63%) tested positive for BSV by ISEM and IC-PCR using badnavirus, but not isolate-specific, primers. The symptoms on the 10 samples that tested negative were not typical of BSV infection. One asymptomatic leaf sample (4%) also tested positive for BSV. To validate the PCR results, the nucleotide sequence of the amplicon from a plant showing the most prevalent foliar symptom type was determined. This sequence (GenBank Accession No. DQ674317) had ≤86% homology to the corresponding ORF III polyprotein region of BSV and other badnaviruses. Neither CMV nor BanMMV was detected in any of the 52 samples tested. From these results, it was concluded that "mosaico" disease of organic Cavendish bananas in northern Peru is associated frequently with BSV infection and that there is a high incidence of BSV infection in this area. To our knowledge, this is the first report of BSV occurrence in Peru. It was both surprising and interesting that neither BSV-OL nor BSV-GF, the two BSV isolates found most commonly in banana (Musa AAA) and plantain (Musa AAB) in South and Central America (B. E. L. Lockhart, unpublished), was detected in Cavendish banana in northern Peru. Failure to detect BSV-OL and BSV-GF suggests that field infection may be due to vertical transmission by clonal propagation rather than to horizontal transmission from local plantain and that control of "mosaico" disease could therefore be achieved by use of virus-free planting material. References: (1) A. D. W. Geering et al. Phytopathology 90:921, 2000. (2) B. E. L. Lockhart et al. Phytopathology 82:921, 1992.

19.
Plant Dis ; 90(6): 834, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30781273

RESUMO

Hostas (Hosta spp.) are one of the most widely grown and economically important landscape perennials in the nursery industry in North America. Several viruses including Hosta virus X (HVX), Tobacco rattle virus (TRV), Tobacco ringspot virus (ToRSV), Tomato ringspot virus (TomRSV), Impatiens necrotic spot virus (INSV), and Tomato spotted wilt virus (TSWV) are known to occur in hostas (4). This report confirms the occurrence of an additional virus, Arabis mosaic virus (ArMV), in hostas in North America. This virus was first identified during the summer of 2004 in Hosta fortunei 'Sharmon' in several garden centers in Minneapolis and St. Paul, MN. Entire lots of this variety, numbering several dozen plants, showed symptoms consisting of blanching of the foliage similar to those caused by ToRSV and TomRSV infection (4). Symptoms persisted throughout the growing season. Virus-like particles, 28 to 30 nm in diameter, were observed by electron microscopy in partially purified extracts of symptomatic leaf tissue following fixation with 5% glutaraldehyde and negative staining with 2% sodium phosphotungstate, pH 7.0. Particles had an angular outline and some were penetrated by stain. No other virus-like particles were observed in these extracts. The particles were identified as those of ArMV. Identification was made using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) and immunosorbent electron microscopy (ISEM) with antiserum to ArMV (PVAS-587) obtained from the American Type Culture Collection, Manassas, VA. In the spring and summer of 2005, ArMV was again identified as described above in 'Sharmon', H. undulata 'Albomarginata' samples from Minnesota, Michigan, and Nebraska, and H. 'Marion Bachman' and H. 'Touch of Class' from two wholesale nurseries in Minnesota. Symptoms in these hosta cultivars were similar to those observed in 'Sharmon' and were accompanied by stunting and leaf deformation. A portion of the coat protein (CP) gene of the ArMV isolate from 'Sharmon', designated ArMV-H, was amplified using reverse transcription-polymerase chain reaction (RT-PCR) with ArMV-specific CP primers (3) and total RNA extracted with a RNeasy Plant Mini Kit (Qiagen Inc., Valencia, CA). Amplicons of the expected size (220 bp) were cloned and five clones were sequenced. Nucleotide sequence identities of the ArMV-H CP sequence to corresponding ArMV databank entries varied from 94 to 88% (Genbank Accession Nos. AY017339 and D10086 and X55460 and X81815, respectively). Interestingly, the hosta ArMV isolate was not transmitted by mechanical inoculation to diagnostically susceptible indicator plants (cucumber, tobacco, and petunia) (2) or to hosta (H. undulata 'Albormarginata', H. 'Honeybells', and H. 'Royal Standard'). Testing by using ELISA and ISEM showed that 'Sharmon' source plants contained high levels of ArMV antigen and virions, and a high percentage of virions were not penetrated by negative stain, indicating that they were not empty (i.e., devoid of RNA). It appears that ArMV-H may be transmitted only vertically, (i.e., clonal propagation) and this raises some interesting questions about the molecular basis of this anomaly. An isolate of ArMV from hops was similarly reported to have a very restricted host range (1) suggesting a possibility of a common mechanism of host range restriction. References: (1) K. R. Bock. Ann. Appl. Biol. 57:431, 1966. (2) A. A. Brunt et al. Viruses of Plants. CAB Internacional Mycological Institute, Wallingford, UK, 1995. (3) P. Kominek et al. Acta Virol. 47:199, 2003. (4) B. E. L. Lockhart and S. Currier. Acta Hortic. 432:62, 1996.

20.
Arch Virol ; 150(4): 787-96, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15785970

RESUMO

We have sequenced the complete genome of an isolate of Banana streak virus from banana cv. 'Mysore' and show that it is sufficiently different from a previously characterised isolate from cv. 'Obino l'Ewai' to warrant recognition as a distinct species, for which the name Banana streak Mysore virus (BSMysV) is proposed. The structure of the BSMysV genome was typical of badnaviruses in general, although ORF I had a non-conventional start codon. Evidence that at least part of the BSMysV genome is integrated in the B genome of cultivated Musa is presented and transmissibility by the mealybug Planococcus citri also demonstrated.


Assuntos
Badnavirus/classificação , Badnavirus/genética , DNA Viral/genética , Genoma de Planta , Musa/virologia , Integração Viral , Sequência de Bases , Primers do DNA , Modelos Moleculares , Dados de Sequência Molecular , Musa/genética , Conformação de Ácido Nucleico , Fases de Leitura Aberta , Filogenia , Reação em Cadeia da Polimerase
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