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Zwolinski AM, Brigden A, Rey MEC. Differences in the 3' intergenic region and the V2 protein of two sequence variants of tomato curly stunt virus play an important role in disease pathology in Nicotiana benthamiana. PLoS One 2023; 18:e0286149. [PMID: 37220127 DOI: 10.1371/journal.pone.0286149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 05/10/2023] [Indexed: 05/25/2023] Open
Abstract
Tomato production in South Africa is threatened by the emergence of tomato curly stunt virus (ToCSV), a monopartite Begomovirus transmitted by the whitefly vector Bemisia tabaci (Genn.). We investigated the role of sequence differences present in the 3' intergenic region (IR) and the V2 coding region on the differing infectivity of ToCSV sequence variant isolates V30 and V22 in the model host Nicotiana benthamiana. Using virus mutant chimeras, we determined that the development of the upward leaf roll symptom phenotype is mediated by sequence differences present in the 3' IR containing the TATA-associated composite element. Sequence differences present in the V2 coding region are responsible for modulating disease severity and symptom recovery in V22-infected plants. Serine substitution of V22 V2 Val27 resulted in a significant increase in disease severity with reduced recovery, the first study to demonstrate the importance of this V2 residue in disease development. Two putative ORFs, C5 and C6, were identified using in silico analysis and detection of an RNA transcript spanning their coding region suggests that these ORFs may be transcribed during infection. Additional virus-derived RNA transcripts spanning multiple ORFs and crossing the boundaries of recognised polycistronic transcripts, as well as the origin of replication within the IR, were detected in ToCSV-infected plants providing evidence of bidirectional readthrough transcription. From our results, we conclude that the diverse responses of the model host to ToCSV infection is influenced by select sequence differences and our findings provide several avenues for further investigation into the mechanisms behind these responses to infection.
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Affiliation(s)
- Alexander M Zwolinski
- School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, South Africa
| | - Alison Brigden
- School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, South Africa
| | - Marie E C Rey
- School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, South Africa
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2
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Monjane AL, Dellicour S, Hartnady P, Oyeniran KA, Owor BE, Bezuidenhout M, Linderme D, Syed RA, Donaldson L, Murray S, Rybicki EP, Kvarnheden A, Yazdkhasti E, Lefeuvre P, Froissart R, Roumagnac P, Shepherd DN, Harkins GW, Suchard MA, Lemey P, Varsani A, Martin DP. Symptom evolution following the emergence of maize streak virus. eLife 2020; 9:51984. [PMID: 31939738 PMCID: PMC7034976 DOI: 10.7554/elife.51984] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 01/14/2020] [Indexed: 11/24/2022] Open
Abstract
For pathogens infecting single host species evolutionary trade-offs have previously been demonstrated between pathogen-induced mortality rates and transmission rates. It remains unclear, however, how such trade-offs impact sub-lethal pathogen-inflicted damage, and whether these trade-offs even occur in broad host-range pathogens. Here, we examine changes over the past 110 years in symptoms induced in maize by the broad host-range pathogen, maize streak virus (MSV). Specifically, we use the quantified symptom intensities of cloned MSV isolates in differentially resistant maize genotypes to phylogenetically infer ancestral symptom intensities and check for phylogenetic signal associated with these symptom intensities. We show that whereas symptoms reflecting harm to the host have remained constant or decreased, there has been an increase in how extensively MSV colonizes the cells upon which transmission vectors feed. This demonstrates an evolutionary trade-off between amounts of pathogen-inflicted harm and how effectively viruses position themselves within plants to enable onward transmission.
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Affiliation(s)
- Adérito L Monjane
- Fish Health Research Group, Norwegian Veterinary Institute, Oslo, Norway.,Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Simon Dellicour
- Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory for Clinical and Epidemiological Virology, KU Leuven - University of Leuven, Leuven, Belgium.,Spatial Epidemiology Laboratory (SpELL), Université Libre de Bruxelles, Brussels, Belgium
| | - Penelope Hartnady
- Computational Biology Division, Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory, Cape Town, South Africa
| | - Kehinde A Oyeniran
- Computational Biology Division, Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory, Cape Town, South Africa
| | - Betty E Owor
- Department of Agricultural Production, School of Agricultural Sciences, Makerere University, Kampala, Uganda
| | - Marion Bezuidenhout
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Daphné Linderme
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Rizwan A Syed
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Lara Donaldson
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Shane Murray
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Edward P Rybicki
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa
| | - Anders Kvarnheden
- Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Elham Yazdkhasti
- Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | | | - Rémy Froissart
- University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut de recherche pour le développement (IRD), UMR 5290, Maladie Infectieuses & Vecteurs: Écologie, Génétique Évolution & Contrôle" (MIVEGEC), Montpellier, France
| | - Philippe Roumagnac
- CIRAD, BGPI, Montpellier, France.,BGPI, INRA, CIRAD, SupAgro, Univ Montpellier, Montpellier, France
| | - Dionne N Shepherd
- Molecular and Cell Biology Department, University of Cape Town, Cape Town, South Africa.,Research Office, University of Cape Town, Cape Town, South Africa
| | - Gordon W Harkins
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Bellville, South Africa
| | - Marc A Suchard
- Department of Biomathematics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Philippe Lemey
- Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory for Clinical and Epidemiological Virology, KU Leuven - University of Leuven, Leuven, Belgium
| | - Arvind Varsani
- The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, United States.,Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town, South Africa
| | - Darren P Martin
- Computational Biology Division, Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory, Cape Town, South Africa
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3
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Zhang J, Dang M, Huang Q, Qian Y. Determinants of Disease Phenotype Differences Caused by Closely-Related Isolates of Begomovirus Betasatellites Inoculated with the Same Species of Helper Virus. Viruses 2015; 7:4945-59. [PMID: 26389936 PMCID: PMC4584297 DOI: 10.3390/v7092853] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 08/25/2015] [Accepted: 08/28/2015] [Indexed: 01/03/2023] Open
Abstract
Tomato yellow leaf curl China virus (TYLCCNV) is a monopartite begomovirus associated with different betasatellites. In this study, we investigate two different isolates of Tomato yellow leaf curl China betasatellite (TYLCCNB) to determine what features of the viral genome are required for induction of characteristic phenotypic differences between closely-related betasatellite. When co-agroinoculated with TYLCCNV into Nicotiana spp. and tomato plants, TYLCCNB-Y25 induced only leaf curling on all hosts, while TYLCCNB-Y10 also induced enations, vein yellowing, and shoot distortions. Further assays showed that βC1 of TYLCCNB-Y25 differs from that of TYLCCNB-Y10 in symptom induction and transcriptional modulating. Hybrid satellites were constructed in which the βC1 gene or 200 nt partial promoter-like fragment upstream of the βC1 were exchanged. Infectivity assays showed that a TYLCCNB-Y25 hybrid with the intact TYLCCNB-Y10 βC1 gene was able to induce vein yellowing, shoot distortions, and a reduced size and number of enations. A TYLCCNB-Y10 hybrid with the intact TYLCCNB-Y25 βC1 gene produced only leaf curling. In contrast, the TYLCCNB-Y25 and TYLCCNB-Y10 hybrids with swapped partial promoter-like regions had little effect on the phenotypes induced by wild-type betasatellites. Further experiments showed that the TYLCCNB-Y25 hybrid carrying the C-terminal region of TYLCCNB-Y10 βC1 induced TYLCCNB-Y10-like symptoms. These findings indicate that the βC1 protein is the major symptom determinant and that the C-terminal region of βC1 plays an important role in symptom induction.
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Affiliation(s)
- Jie Zhang
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Mingqing Dang
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
| | - Qingqing Huang
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
| | - Yajuan Qian
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
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4
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Nygren J, Shad N, Kvarnheden A, Westerbergh A. Variation in susceptibility to Wheat dwarf virus among wild and domesticated wheat. PLoS One 2015; 10:e0121580. [PMID: 25837893 PMCID: PMC4383415 DOI: 10.1371/journal.pone.0121580] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 02/13/2015] [Indexed: 01/06/2023] Open
Abstract
We investigated the variation in plant response in host-pathogen interactions between wild (Aegilops spp., Triticum spp.) and domesticated wheat (Triticum spp.) and Wheat dwarf virus (WDV). The distribution of WDV and its wild host species overlaps in Western Asia in the Fertile Crescent, suggesting a coevolutionary relationship. Bread wheat originates from a natural hybridization between wild emmer wheat (carrying the A and B genomes) and the wild D genome donor Aegilops tauschii, followed by polyploidization and domestication. We studied whether the strong selection during these evolutionary processes, leading to genetic bottlenecks, may have resulted in a loss of resistance in domesticated wheat. In addition, we investigated whether putative fluctuations in intensity of selection imposed on the host-pathogen interactions have resulted in a variation in susceptibility to WDV. To test our hypotheses we evaluated eighteen wild and domesticated wheat taxa, directly or indirectly involved in wheat evolution, for traits associated with WDV disease such as leaf chlorosis, different growth traits and WDV content. The plants were exposed to viruliferous leafhoppers (Psammotettix alienus) in a greenhouse trial and evaluated at two time points. We found three different plant response patterns: i) continuous reduction in growth over time, ii) weak response at an early stage of plant development but a much stronger response at a later stage, and iii) remission of symptoms over time. Variation in susceptibility may be explained by differences in the intensity of natural selection, shaping the coevolutionary interaction between WDV and the wild relatives. However, genetic bottlenecks during wheat evolution have not had a strong impact on WDV resistance. Further, this study indicates that the variation in susceptibility may be associated with the genome type and that the ancestor Ae. tauschii may be useful as genetic resource for the improvement of WDV resistance in wheat.
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Affiliation(s)
- Jim Nygren
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology in Uppsala, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Nadeem Shad
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology in Uppsala, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anders Kvarnheden
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology in Uppsala, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anna Westerbergh
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology in Uppsala, Swedish University of Agricultural Sciences, Uppsala, Sweden
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5
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Monjane AL, Pande D, Lakay F, Shepherd DN, van der Walt E, Lefeuvre P, Lett JM, Varsani A, Rybicki EP, Martin DP. Adaptive evolution by recombination is not associated with increased mutation rates in Maize streak virus. BMC Evol Biol 2012; 12:252. [PMID: 23268599 PMCID: PMC3556111 DOI: 10.1186/1471-2148-12-252] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 12/12/2012] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Single-stranded (ss) DNA viruses in the family Geminiviridae are proving to be very useful in real-time evolution studies. The high mutation rate of geminiviruses and other ssDNA viruses is somewhat mysterious in that their DNA genomes are replicated in host nuclei by high fidelity host polymerases. Although strand specific mutation biases observed in virus species from the geminivirus genus Mastrevirus indicate that the high mutation rates in viruses in this genus may be due to mutational processes that operate specifically on ssDNA, it is currently unknown whether viruses from other genera display similar strand specific mutation biases. Also, geminivirus genomes frequently recombine with one another and an alternative cause of their high mutation rates could be that the recombination process is either directly mutagenic or produces a selective environment in which the survival of mutants is favoured. To investigate whether there is an association between recombination and increased basal mutation rates or increased degrees of selection favoring the survival of mutations, we compared the mutation dynamics of the MSV-MatA and MSV-VW field isolates of Maize streak virus (MSV; Mastrevirus), with both a laboratory constructed MSV recombinant, and MSV recombinants closely resembling MSV-MatA. To determine whether strand specific mutation biases are a general characteristic of geminivirus evolution we compared mutation spectra arising during these MSV experiments with those arising during similar experiments involving the geminivirus Tomato yellow leaf curl virus (Begomovirus genus). RESULTS Although both the genomic distribution of mutations and the occurrence of various convergent mutations at specific genomic sites indicated that either mutation hotspots or selection for adaptive mutations might elevate observed mutation rates in MSV, we found no association between recombination and mutation rates. Importantly, when comparing the mutation spectra of MSV and TYLCV we observed similar strand specific mutation biases arising predominantly from imbalances in the complementary mutations G → T: C → A. CONCLUSIONS While our results suggest that recombination does not strongly influence mutation rates in MSV, they indicate that high geminivirus mutation rates are at least partially attributable to increased susceptibility of all geminivirus genomes to oxidative damage while in a single stranded state.
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Affiliation(s)
- Adérito L Monjane
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, Cape Town 7701, South Africa
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6
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Rouhibakhsh A, Choudhury NR, Mukherjee SK, Malathi VG. Enhanced nicking activity of Rep in presence of pre-coat protein of Mungbean yellow mosaic India virus. Virus Genes 2011; 44:356-61. [DOI: 10.1007/s11262-011-0701-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Accepted: 12/05/2011] [Indexed: 10/14/2022]
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7
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Monjane AL, van der Walt E, Varsani A, Rybicki EP, Martin DP. Recombination hotspots and host susceptibility modulate the adaptive value of recombination during maize streak virus evolution. BMC Evol Biol 2011; 11:350. [PMID: 22136133 PMCID: PMC3280948 DOI: 10.1186/1471-2148-11-350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 12/02/2011] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Maize streak virus -strain A (MSV-A; Genus Mastrevirus, Family Geminiviridae), the maize-adapted strain of MSV that causes maize streak disease throughout sub-Saharan Africa, probably arose between 100 and 200 years ago via homologous recombination between two MSV strains adapted to wild grasses. MSV recombination experiments and analyses of natural MSV recombination patterns have revealed that this recombination event entailed the exchange of the movement protein - coat protein gene cassette, bounded by the two genomic regions most prone to recombination in mastrevirus genomes; the first surrounding the virion-strand origin of replication, and the second around the interface between the coat protein gene and the short intergenic region. Therefore, aside from the likely adaptive advantages presented by a modular exchange of this cassette, these specific breakpoints may have been largely predetermined by the underlying mechanisms of mastrevirus recombination. To investigate this hypothesis, we constructed artificial, low-fitness, reciprocal chimaeric MSV genomes using alternating genomic segments from two MSV strains; a grass-adapted MSV-B, and a maize-adapted MSV-A. Between them, each pair of reciprocal chimaeric genomes represented all of the genetic material required to reconstruct - via recombination - the highly maize-adapted MSV-A genotype, MSV-MatA. We then co-infected a selection of differentially MSV-resistant maize genotypes with pairs of reciprocal chimaeras to determine the efficiency with which recombination would give rise to high-fitness progeny genomes resembling MSV-MatA. RESULTS Recombinants resembling MSV-MatA invariably arose in all of our experiments. However, the accuracy and efficiency with which the MSV-MatA genotype was recovered across all replicates of each experiment depended on the MSV susceptibility of the maize genotypes used and the precise positions - in relation to known recombination hotspots - of the breakpoints required to re-create MSV-MatA. Although the MSV-sensitive maize genotype gave rise to the greatest variety of recombinants, the measured fitness of each of these recombinants correlated with their similarity to MSV-MatA. CONCLUSIONS The mechanistic predispositions of different MSV genomic regions to recombination can strongly influence the accessibility of high-fitness MSV recombinants. The frequency with which the fittest recombinant MSV genomes arise also correlates directly with the escalating selection pressures imposed by increasingly MSV-resistant maize hosts.
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Affiliation(s)
- Adérito L Monjane
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
| | | | - Arvind Varsani
- Biomolecular Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
- Electron Microscope Unit, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
| | - Edward P Rybicki
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
- Computational Biology Group, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, Cape Town, South Africa
| | - Darren P Martin
- Computational Biology Group, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, Cape Town, South Africa
- Centre for High-Performance Computing, Rosebank, Cape Town, South Africa
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8
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Jun SC, Lee SJ, Park HJ, Kang JY, Leem YE, Yang TH, Chang MH, Kim JM, Jang SH, Kim HG, Han DM, Chae KS, Jahng KY. The MpkB MAP kinase plays a role in post-karyogamy processes as well as in hyphal anastomosis during sexual development in Aspergillus nidulans. J Microbiol 2011; 49:418-30. [DOI: 10.1007/s12275-011-0193-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 01/10/2011] [Indexed: 12/17/2022]
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9
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Chowda-Reddy RV, Achenjang F, Felton C, Etarock MT, Anangfac MT, Nugent P, Fondong VN. Role of a geminivirus AV2 protein putative protein kinase C motif on subcellular localization and pathogenicity. Virus Res 2008; 135:115-24. [PMID: 18405995 DOI: 10.1016/j.virusres.2008.02.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2007] [Revised: 02/18/2008] [Accepted: 02/25/2008] [Indexed: 11/30/2022]
Abstract
Virus-derived genes or genome fragments are increasingly being used to generate transgenic plants with resistance to plant viruses. There is need to rapidly investigate these genes in plants using transient expression prior to using them as transgenes since they may be pathogenic to plants. In this study, we investigated the AV2 protein encoded by East African cassava mosaic Cameroon virus, a virus associated with a cassava disease epidemic in western Africa. For subcellular localization, AV2 was fused to the yellow fluorescent protein (YFP) and expressed in Nicotiana benthamiana. Confocal analyses showed that AV2-YFP localizes mainly in the cytoplasm. Because it overlaps with the coat protein gene and therefore could be used to generate transgenic plants for resistance to geminiviruses, we investigated its pathogenesis in N. benthamiana by using the Potato virus X (PVX) vector. The chimeric virus PVX-AV2 induced a mild mottling in infected plants and was shown to suppress virus-induced gene silencing (VIGS). Using point mutations, we show here that AV2 pathogenicity is dependent on a conserved putative protein kinase C (PKC) phosphorylation motif. Because of its pathogenicity and ability to suppress RNA silencing, AV2 transgenic plants will less likely provide a control to geminiviruses, indeed it may weaken the resistance of the plant. We therefore suggest the use of the AV2 putative PKC mutants to generate transgenic plants.
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Affiliation(s)
- R V Chowda-Reddy
- Department of Biological Sciences, Delaware State University, 1200 North DuPont Highway, Dover, DE 19901, United States
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10
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van der Walt E, Palmer KE, Martin DP, Rybicki EP. Viable chimaeric viruses confirm the biological importance of sequence specific maize streak virus movement protein and coat protein interactions. Virol J 2008; 5:61. [PMID: 18489800 PMCID: PMC2430021 DOI: 10.1186/1743-422x-5-61] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Accepted: 05/20/2008] [Indexed: 11/29/2022] Open
Abstract
Background A variety of interactions between up to three different movement proteins (MPs), the coat protein (CP) and genomic DNA mediate the inter- and intra-cellular movement of geminiviruses in the genus Begomovirus. Although movement of viruses in the genus Mastrevirus is less well characterized, direct interactions between a single MP and the CP of these viruses is also clearly involved in both intra- and intercellular trafficking of virus genomic DNA. However, it is currently unknown how specific these MP-CP interactions are, nor how disruption of these interactions might impact on virus viability. Results Using chimaeric genomes of two strains of Maize streak virus (MSV) we adopted a genetic approach to investigate the gross biological effects of interfering with interactions between virus MP and CP homologues derived from genetically distinct MSV isolates. MP and CP genes were reciprocally exchanged, individually and in pairs, between maize (MSV-Kom)- and Setaria sp. (MSV-Set)-adapted isolates sharing 78% genome-wide sequence identity. All chimaeras were infectious in Zea mays c.v. Jubilee and were characterized in terms of symptomatology and infection efficiency. Compared with their parental viruses, all the chimaeras were attenuated in symptom severity, infection efficiency, and the rate at which symptoms appeared. The exchange of individual MP and CP genes resulted in lower infection efficiency and reduced symptom severity in comparison with exchanges of matched MP-CP pairs. Conclusion Specific interactions between the mastrevirus MP and CP genes themselves and/or their expression products are important determinants of infection efficiency, rate of symptom development and symptom severity.
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Affiliation(s)
- Eric van der Walt
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa.
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11
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Geminivirus strain demarcation and nomenclature. Arch Virol 2008; 153:783-821. [DOI: 10.1007/s00705-008-0037-6] [Citation(s) in RCA: 402] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 12/27/2007] [Indexed: 10/22/2022]
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12
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Hehnle S, Wege C, Jeske H. Interaction of DNA with the movement proteins of geminiviruses revisited. J Virol 2004; 78:7698-706. [PMID: 15220444 PMCID: PMC434128 DOI: 10.1128/jvi.78.14.7698-7706.2004] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2003] [Accepted: 03/15/2004] [Indexed: 11/20/2022] Open
Abstract
Geminiviruses manage the transport of their DNA within plants with the help of three proteins, the coat protein (CP), the nuclear shuttle protein (NSP), and the movement protein (MP). The DNA-binding capabilities of CP, NSP, and MP of Abutilon mosaic virus (AbMV; family Geminiviridae; genus Begomovirus) were scrutinized using gel mobility shift assays and electron microscopy. CP and NSP revealed a sequence-independent affinity for both double-stranded and single-stranded DNA, as has been previously reported for other begomoviruses. MP interacted selectively with dimeric supercoiled plasmid DNA in the electrophoretic assay. Further apparent size- and form-selective binding capacities of MP have been previously reported for another geminivirus (Bean dwarf mosaic virus), but in the case of AbMV, they have been identified as the result of electrophoretic interference rather than of complex formation. Without these complications, electron microscopy confirmed the assembly of double-stranded supercoiled DNA with NSP and MP into conspicuous structures and provided the first direct evidence for cooperative interaction of MP, NSP, and DNA. Based on these results and previous ones, a transport model of geminiviruses is discussed in which NSP packages DNA and MP anchors this complex to the protoplasmic leaflets of plasma membranes and microsomes for cell-to-cell movement.
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Affiliation(s)
- Stefan Hehnle
- Department of Molecular Biology and Plant Virology, Institute of Biology, University of Stuttgart, D-70550 Stuttgart, Germany
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13
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Casado CG, Javier Ortiz G, Padron E, Bean SJ, McKenna R, Agbandje-McKenna M, Boulton MI. Isolation and characterization of subgenomic DNAs encapsidated in “single” T = 1 isometric particles of Maize streak virus. Virology 2004; 323:164-71. [PMID: 15165828 DOI: 10.1016/j.virol.2004.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Revised: 01/29/2004] [Accepted: 02/19/2004] [Indexed: 11/25/2022]
Abstract
"Single" T = 1 isometric particles of Maize streak virus (MSV) have been isolated from infected maize leaves. Biochemical and genetic characterizations show that these particles contain subgenomic (sg) MSV DNA encapsidated by the MSV coat protein. The largest sg DNA is 1.56 kb, slightly larger than half genome size, although sg DNAs as small as 0.2 kb were also cloned. The sg DNAs are not infectious, and they do not appear to play a role in the pathogenicity of MSV. This is the first report of sg DNAs for MSV and, to our knowledge, the first time that encapsidated sg DNAs have been characterized at the sequence level for any geminivirus. These data will assist in our investigations into the role of genomic DNA in the formation of the unique geminate capsid architecture of the Geminiviridae.
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Affiliation(s)
- Carolina G Casado
- Department of Biochemistry and Molecular Biology, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, USA
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14
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Martin DP, Rybicki EP. Investigation of Maize streak virus pathogenicity determinants using chimaeric genomes. Virology 2002; 300:180-8. [PMID: 12350349 DOI: 10.1006/viro.2002.1458] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Genes and intergenic regions were reciprocally exchanged between a highly pathogenic Maize streak virus (MSV) isolate (MSV-MatA) and three less pathogenic isolates (MSV-Kom, MSV-R2, and MSV-VW) to determine the contribution of individual genome constituents to MSV pathogenicity in maize. Comparison of disease symptoms produced by the 54 resulting chimaeras and parental viruses enabled identification of genome constituents that are primarily responsible for the heightened pathogenicity of MSV-MatA in maize. Whereas pathogenicity determinants were detected in all of the MSV genomic regions examined, generally only chimaeras containing the MSV-MatA long intergenic region, coat protein gene, and/or movement protein gene were more pathogenic than the milder MSV isolates from which most of their genomes were derived. The pathogenicity of chimeras was strongly influenced by the relatedness of their parental viruses and evidence was found of nucleotide sequence-dependent interactions between both coding and intergenic regions.
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Affiliation(s)
- D P Martin
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag, Rondebosch, 7701, Western Cape, South Africa
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15
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Liu H, Lucy AP, Davies JW, Boulton MI. A single amino acid change in the coat protein of Maize streak virus abolishes systemic infection, but not interaction with viral DNA or movement protein. MOLECULAR PLANT PATHOLOGY 2001; 2:223-8. [PMID: 20573010 DOI: 10.1046/j.1464-6722.2001.00068.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Summary Functional coat protein (CP) is important for host plant infection by monopartite geminiviruses. We identified a proline-cysteine-lysine (PCK) motif at amino acids 180-182 of the maize streak virus (MSV) CP that is conserved in most of the cereal-infecting Mastreviruses. Substitution of the lysine (K) with a valine (V) in the CP of MSV to produce mutant MSVCP182V abolished systemic infection in maize plants, although the mutant replicated around the inoculation site and, unlike other MSV CP mutants, enabled single-stranded (ss) DNA accumulation in suspension cells. The stability of the mutant protein, CP182V, in infected cells was confirmed by immunoblotting, but virions could not be detected. Like the wild-type (wt) CP, CP182V localized to the nucleus when expressed in insect and tobacco cells, and the Escherichia coli-expressed protein bound both ss and double-stranded DNA and interacted with movement protein in vitro. Taken together, these data suggest that mutation of amino acid 182 affects virion formation of MSV, either by affecting encapsidation per se or by affecting particle stability, and that virions are necessary for the long-distance movement of MSV in maize plants.
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Affiliation(s)
- H Liu
- John Innes Centre, Colney, Norwich NR4 7UH, UK
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16
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Nikovics K, Simidjieva J, Peres A, Ayaydin F, Pasternak T, Davies JW, Boulton MI, Dudits D, Horváth GV. Cell-cycle, phase-specific activation of Maize streak virus promoters. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2001; 14:609-617. [PMID: 11332725 DOI: 10.1094/mpmi.2001.14.5.609] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It is believed that geminiviral DNA replication is coupled to the cell-cycle regulatory complex of the plant cell and that the virus-early (complementary or C sense) gene products REP and REPA may be able to manipulate the regulation of the cycle. In this study, we examined expression from the promoters of Maize streak virus (MSV) in transgenic maize plants and cells to determine whether they showed cell-cycle specificity. Histochemical staining of plant roots containing "long and short" C-sense promoter sequences upstream of the GUS (beta-glucuronidase) reporter gene showed that promoter activity was restricted to the meristematic region of the roots and was enhanced by 2,4-dichlorophenoxy acetic acid (2,4-D) treatment. Analysis of reporter gene and cell-cycle-specific gene transcript levels coupled with flow cytometric data in synchronized transgenic maize cells revealed that all of the MSV promoters showed cell-cycle specificity. The coat protein gene promoter showed highest activity in early G2, whereas the C-sense promoter sequences produced two peaks of activity in the S and G2 cell-cycle phases.
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Affiliation(s)
- K Nikovics
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged
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17
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Abstract
Maize streak virus (MSV) (genus Mastrevirus; family Geminiviridae) causes what is considered the most important and widespread disease of maize in sub-Saharan Africa. Maize streak was named by Storey in 1925. Since his classical work on the virus and its leafhopper vectors of the genus Cicadulina China, MSV has been the subject of intensive research. Aspects concerning the geographical distribution, virus diversity, molecular characterization, vector-virus relationships and resistance breeding are reviewed. Special emphasis is placed on recent studies of MSV ecology and epidemiology in West Africa.
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Affiliation(s)
- N A Bosque-Pérez
- Department of Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339, USA.
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18
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Kotlizky G, Boulton MI, Pitaksutheepong C, Davies JW, Epel BL. Intracellular and intercellular movement of maize streak geminivirus V1 and V2 proteins transiently expressed as green fluorescent protein fusions. Virology 2000; 274:32-8. [PMID: 10936086 DOI: 10.1006/viro.2000.0415] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Transient expression of the maize streak geminivirus virion-sense proteins V1 and V2 (movement protein, MP, and coat protein, CP, respectively) in maize leaves allowed investigation of their roles in inter- and intracellular movement. Bombardment of a construct directing expression of a V1:green fluorescent protein (GFP) fusion product resulted in significantly increased spread of fluorescence from the bombarded cell to adjacent cells compared to that obtained following expression of free GFP. A mutant V1:GFP fusion product exhibited markedly less movement than the V1:GFP protein. Thus, the MSV V1 protein moves from cell to cell in the absence of other viral proteins. However, V1:GFP did not localize to plasmodesmata in maize or tobacco leaves although a tobacco mosaic virus MP:GFP fusion protein was shown to do so in tobacco. The CP:GFP fusion product targeted exclusively to the nucleus and did not move from cell to cell or exit the nucleus when expressed alone. When coexpressed with V1, some CP:GFP fluorescence was seen at the cell periphery in a proportion of cells, but in no case was cell-to-cell movement of CP:GFP detected. The likely roles of V1 and CP in MSV movement are discussed.
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Affiliation(s)
- G Kotlizky
- Department of Plant Sciences, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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19
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Mazithulela G, Sudhakar D, Heckel T, Mehlo L, Christou P, Davies JW, Boulton MI. The maize streak virus coat protein transcription unit exhibits tissue-specific expression in transgenic rice. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2000; 155:21-29. [PMID: 10773336 DOI: 10.1016/s0168-9452(99)00256-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Maize streak geminivirus (MSV) is a single-stranded DNA virus that infects cereals and other grasses. A promoter region incorporating the MSV large intergenic region and movement protein gene sequence was ligated to the gus (beta-glucuronidase) reporter gene which replaced the virus coat protein (CP) gene. The CP promoter activity was analysed in transgenic rice plants (Oryza sativa L.) and was compared with that obtained in plants transformed with the gus gene downstream of the cauliflower mosaic virus (CaMV) 35S promoter. The MSV CP promoter activity varied in the five plant lines tested, but was always less than that of the CaMV promoter. Histochemistry showed that the MSV CP promoter was active in cells of regenerating callus but in regenerated plants it provided an expression pattern restricted to the vascular tissues of the root, stem, leaf and floral organs. Expression was highest in phloem-associated tissues of the vegetative organs and was absent from the tip and elongation region of seedling roots. Thus, the MSV CP promoter shows a degree of developmental regulation and can be used to confer tissue-specific expression in transgenic rice plants.
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Affiliation(s)
- G Mazithulela
- John Innes Centre, Norwich Research Park, Colney, Norwich, UK
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20
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Liu H, Boulton MI, Thomas CL, Prior DA, Oparka KJ, Davies JW. Maize streak virus coat protein is karyophyllic and facilitates nuclear transport of viral DNA. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 1999; 12:894-900. [PMID: 10517029 DOI: 10.1094/mpmi.1999.12.10.894] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Transport of maize streak virus (MSV) DNA into the nucleus of host cells is essential for virus replication and the presence of virus particles in the nuclei of infected cells implies that coat protein (CP) must enter the nucleus. To see if CP is imported into the nucleus in the absence of other viral gene products, the MSV CP gene was expressed in insect cells with a baculovirus vector system, and also in tobacco protoplasts with a cauliflower mosaic virus (CaMV) 35S promoter-driven transient gene expression vector. Immunofluorescent staining showed that the CP accumulated in the nuclei of both insect and tobacco cells. Mutagenesis of a potential nuclear localization signal in the CP resulted in cytoplasmic accumulation of the mutant protein. We have shown previously that the CP binds to single-stranded (ss) and double-stranded (ds) viral DNA. To investigate if CP might also be involved in viral DNA nuclear transport, Escherichia coli-expressed CP, together with TOTO-1-labeled viral ss or ds DNA, was microinjected into maize and tobacco epidermal cells. Both ss and ds DNA moved into the nucleus when co-injected with the CP but not with E. coli proteins alone. These results suggest that, in addition to entering the nucleus where it is required for encapsidation of the viral ss DNA, the MSV CP facilitates the rapid transport of viral (ss or ds) DNA into the nucleus.
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Affiliation(s)
- H Liu
- Department of Virus Research, John Innes Centre, Norwich, U.K
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21
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Affiliation(s)
- K E Palmer
- Department of Microbiology, University of Cape Town, Western Cape, South Africa
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22
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Heath JD, Boulton MI, Raineri DM, Doty SL, Mushegian AR, Charles TC, Davies JW, Nester EW. Discrete regions of the sensor protein virA determine the strain-specific ability of Agrobacterium to agroinfect maize. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 1997; 10:221-7. [PMID: 9057328 DOI: 10.1094/mpmi.1997.10.2.221] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The ability of Agrobacterium strains to infect transformation-recalcitrant maize plants has been shown to be determined mainly by the virA locus, implicating vir gene induction as the major factor influencing maize infection. In this report, we further explore the roles of vir induction-associated bacterial factors in maize infection using the technique of agroinfection. The Ti plasmid and virA source are shown to be important in determining the ability of a strain to infect maize, and the monosaccharide binding protein ChvE is absolutely required for maize agroinfection. The linker domain of VirAC58 from an agroinfection-competent strain, C58, is sufficient to convert VirAA6 of a nonagroinfecting strain, A348,to agroinfection competence. The periplasmic domain of VirAC58 is also able to confer a moderate level of agroinfection competence to VirAA6. In addition, the VirAA6 protein from A348 is agroinfection competent when removed from its cognate Ti plasmid background and placed in a pTiC58 background. The presence of a pTiA6-encoded, VirAA6-specific inhibitor is hypothesized and examined.
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Affiliation(s)
- J D Heath
- University of Washington, Department of Microbiology, Seattle 98195-7242, USA
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23
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Wartig L, Kheyr-Pour A, Noris E, De Kouchkovsky F, Jouanneau F, Gronenborn B, Jupin I. Genetic analysis of the monopartite tomato yellow leaf curl geminivirus: roles of V1, V2, and C2 ORFs in viral pathogenesis. Virology 1997; 228:132-40. [PMID: 9123819 DOI: 10.1006/viro.1996.8406] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tomato yellow leaf curl virus (TYLCV) is a whitefly-transmitted geminivirus with a monopartite genome. We have investigated the functions of the V1, V2, and C2 ORFs by mutational analysis. We analyzed the ability of TYLCV mutants containing disrupted ORFs V1, V2, or C2 to replicate, spread, and cause symptoms in Nicotiana benthamiana and tomato plants. All the mutants retained the capability of autonomous replication in protoplast-derived cells of tomato and leaf discs of N. benthamiana, although both V1 and V2 gene products appeared to play a role in the accumulation of viral single-stranded DNA. In contrast, none of the mutants was able to systemically infect tomato plants, demonstrating that the V1, V2, and C2 gene products are all required for a successful infection process in this host. The effect of the mutation in ORF C2 appeared to be host-specific, since N. benthamiana plants were systemically infected, although symptom development was attenuated.
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Affiliation(s)
- L Wartig
- Institut des Sciences Végétales, CNRS, Gif sur Yvette, France
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24
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Peterschmitt M, Granier M, Frutos R, Reynaud B. Infectivity and complete nucleotide sequence of the genome of a genetically distinct strain of maize streak virus from Reunion Island. Arch Virol 1996; 141:1637-50. [PMID: 8893787 DOI: 10.1007/bf01718288] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A complete infectious genome of an isolate of maize streak subgroup 1 geminivirus from Reunion Island (MSV-R) was cloned and sequenced. Using an Agrobacterium tumefaciens Ti plasmid delivery system, the cloned 2.7 kb circular DNA was shown to be infectious in maize. The agroinfected virus could be transmitted by Cicadulina mbila, the most common vector species of MSV in Reunion. Analysis of open reading frames (ORFs) revealed seven potential coding regions including the 4 ORFs conserved in all geminiviruses infecting monocotyledonous plants, the 2 on the viral "+" strand (MP, CP), and the 2 on the complementary "-" strand (RepA, RepB). The nucleotide sequence of MSV-R was compared to previously determined sequence of three African clones from Nigeria (MSV-N), Kenya (MSV-K), and South Africa (MSV-S). More similarity was found between the African clones (97.0-97.3%) than between these and MSV-R (94.4-95.3%). Nucleotide substitutions were frequent in the large intergenic region, particularly in and around the most likely TATA box for the complementary sense genes, and in the 5' end of ORF V1. The comparison of the predicted peptide sequences of the proteins encoded by ORFs MP, RepA and RepB confirmed the higher similarity between the African clones (97.8-99.3%) than between these and MSV-R (95.1-97.1%). However the amino acid sequences of the protein encoded by ORF CP (capsid protein) were very conserved among all the 4 clones, suggesting a high selection pressure on this ORF.
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25
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Briddon RW, Lunness P, Chamberlin LC, Markham PG. Analysis of the genetic variability of maize streak virus. Virus Genes 1994; 9:93-100. [PMID: 7871766 DOI: 10.1007/bf01703439] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The nucleotide sequences of the small intergenic region (SIR) and the gene encoding the coat protein of 12 maize streak virus (MSV) isolates from different geographic locations have been determined. These have been used to assess the variability of the virus and to construct evolutionary dendrograms. For the viruses analyzed, the maximum levels of sequence divergence were found to be 10.9% and 2.0% at the nucleotide and amino acid levels, respectively. A genetically distinct strain of MSV was collected from islands in the Indian ocean. The significance of these findings for detection of the virus in epidemiological studies and breeding of resistant plant varieties is discussed.
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Affiliation(s)
- R W Briddon
- Department of Virus Research, John Innes Institute, John Innes Centre for Plant Science Research, Norwich, UK
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26
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Abstract
Geminiviruses are being used as convenient autonomously replicating vectors for foreign gene amplification in plants. Using tissue culture techniques, they have been adapted for the analysis of the regulation of gene expression in a wide range of hosts, including both mono- and dicotyledonous species. In monocotyledonous plants that are particularly recalcitrant to transformation, geminivirus symptom-induction has been used as a sensitive marker for DNA uptake.
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Affiliation(s)
- J Stanley
- Department of Virus Research, John Innes Institute, Norwich, UK
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27
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Stanley J, Latham JR. A symptom variant of beet curly top geminivirus produced by mutation of open reading frame C4. Virology 1992; 190:506-9. [PMID: 1529551 DOI: 10.1016/0042-6822(92)91243-n] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two beet curly top virus (BCTV) mutants have been constructed in vitro that contain G-to-T transversions either at nucleotide 2682 or at nucleotide 2802 within the overlapping open reading frames (ORFs) C1 and C4. The mutations introduce termination codons in ORF C4 without affecting the amino acids encoded by ORF C1. When agroinoculated into Nicotiana benthamiana the mutants caused stunting and yellowing of the plant and downward leaf curl but not the vein swelling and upward leaf curl symptoms that are characteristic of wild-type BCTV infection in this host. Levels of viral single- and double-stranded DNA forms were similar in mutant and wild-type infections. Symptoms induced by one such mutant in Nicotiana clevelandii and Datura stramonium were less severe than those in wild-type infections and were again qualitatively distinct. The mutants caused symptomless infections in Beta vulgaris, contrasting with stunting, severe leaf curl, and vein swelling symptoms associated with wild-type infection of this host. The levels of mutant DNA in newly expanding asymptomatic leaves frequently reached those of wild-type virus in leaves showing severe symptoms. The results suggest that ORF C4 encodes a protein that is a major determinant of pathogenesis that might affect the hyperplastic response of the host to BCTV infection.
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Affiliation(s)
- J Stanley
- John Innes Institute, John Innes Centre for Plant Science Research, Norwich, United Kingdom
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