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Holeva MC, Sklavounos A, Rajeswaran R, Pooggin MM, Voloudakis AE. Topical Application of Double-Stranded RNA Targeting 2b and CP Genes of Cucumber mosaic virus Protects Plants against Local and Systemic Viral Infection. PLANTS 2021; 10:plants10050963. [PMID: 34066062 PMCID: PMC8151262 DOI: 10.3390/plants10050963] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/19/2021] [Accepted: 04/08/2021] [Indexed: 02/07/2023]
Abstract
Cucumber mosaic virus (CMV) is a destructive plant virus with worldwide distribution and the broadest host range of any known plant virus, as well as a model plant virus for understanding plant–virus interactions. Since the discovery of RNA interference (RNAi) as a major antiviral defense, RNAi-based technologies have been developed for plant protection against viral diseases. In plants and animals, a key trigger of RNAi is double-stranded RNA (dsRNA) processed by Dicer and Dicer-like (DCL) family proteins in small interfering RNAs (siRNAs). In the present study, dsRNAs for coat protein (CP) and 2b genes of CMV were produced in vitro and in vivo and applied onto tobacco plants representing a systemic solanaceous host as well as on a local host plant Chenopodium quinoa. Both dsRNA treatments protected plants from local and systemic infection with CMV, but not against infection with unrelated viruses, confirming sequence specificity of antiviral RNAi. Antiviral RNAi was effective when dsRNAs were applied simultaneously with or four days prior to CMV inoculation, but not four days post inoculation. In vivo-produced dsRNAs were more effective than the in vitro-produced; in treatments with in vivo dsRNAs, dsRNA-CP was more effective than dsRNA-2b, while the effects were opposite with in vitro dsRNAs. Illumina sequencing of small RNAs from in vivo dsRNA-CP treated and non-treated tobacco plants revealed that interference with CMV infection in systemic leaves coincides with strongly reduced accumulation of virus-derived 21- and 22-nucleotide (nt) siRNAs, likely generated by tobacco DCL4 and DCL2, respectively. While the 21-nt class of viral siRNAs was predominant in non-treated plants, 21-nt and 22-nt classes accumulated at almost equal (but low) levels in dsRNA treated plants, suggesting that dsRNA treatment may boost DCL2 activity. Taken together, our findings confirm the efficacy of topical application of dsRNA for plant protection against viruses and shed more light on the mechanism of antiviral RNAi.
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Affiliation(s)
- Maria C. Holeva
- Laboratory of Bacteriology, Scientific Directorate of Phytopathology, Benaki Phytopathological Institute, 14561 Kifissia, Greece;
| | - Athanasios Sklavounos
- Laboratory of Plant Breeding and Biometry, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece;
- Office of Rural Development and Inspections of Kephalonia, Ministry of Rural Development and Food, 28100 Argostoli, Greece
| | - Rajendran Rajeswaran
- Department of Biology, Swiss Federal Institute of Technology (ETH), Universitätsstrasse 2, 8092 Zürich, Switzerland;
| | - Mikhail M. Pooggin
- PHIM Plant Health Institute, University of Montpellier, 34980 Montpellier, France;
| | - Andreas E. Voloudakis
- Laboratory of Plant Breeding and Biometry, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece;
- Correspondence: ; Tel.: +30-2105294213
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Matić S, Noris E, Contin R, Marian D, Thompson JR. Engineering partial resistance to cucumber mosaic virus in tobacco using intrabodies specific for the viral polymerase. PHYTOCHEMISTRY 2019; 162:99-108. [PMID: 30877900 DOI: 10.1016/j.phytochem.2019.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
A single-chain variable antibody fragment (scFv) library tested against the non-structural NSP5 protein of human rotavirus A was screened by a yeast two-hybrid system against three proteins derived from the RNA-dependent RNA polymerase (RdRp) of cucumber mosaic virus (CMV), with the aim of blocking their function and preventing viral infection once expressed in planta. The constructs tested were (i) '2a' consisting of the full-length 2a gene (839 amino acids, aa), (ii) 'Motifs' covering the conserved RdRp motifs (IV-VII) (132 aa) and (iii) 'GDD' located within the conserved RdRp motif VI (GDD, 22 aa). In yeast two-hybrid (Y2H) selection assays the '2a' and 'Motifs' constructs interacted with 96 and 25 library constructs, respectively, while the 'GDD' construct caused transactivation. Y2H-interacting scFvs were analyzed in vivo for their interaction with the 2a and Motifs proteins in a mammalian transient expression system. Eighteen tobacco lines stably transformed with four selected scFvs were produced and screened for resistance against two different CMV isolates. Different levels of resistance and rate of recovery were observed with CMV of both groups I and II, particularly in lines expressing intrabodies against the full-length 2a protein. This work describes for the first time the use of intrabodies against the RdRp of CMV to obtain plants that reduce infection of a pandemic virus, showing that the selected scFvs can modulate virus infection and induce premature recovery in tobacco plants.
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Affiliation(s)
- Slavica Matić
- Plant Virology Group, ICGEB Biosafety Outstation, Ca'Tron di Roncade (TV), Italy; Institute for Sustainable Plant Protection, National Research Council of Italy (IPSP-CNR), Turin (TO), Italy
| | - Emanuela Noris
- Institute for Sustainable Plant Protection, National Research Council of Italy (IPSP-CNR), Turin (TO), Italy
| | - Roberta Contin
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste (TS), Italy
| | - Daniele Marian
- Institute for Sustainable Plant Protection, National Research Council of Italy (IPSP-CNR), Turin (TO), Italy
| | - Jeremy R Thompson
- Plant Virology Group, ICGEB Biosafety Outstation, Ca'Tron di Roncade (TV), Italy; Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, USA.
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Hema M, Sreenivasulu P, Patil BL, Kumar PL, Reddy DVR. Tropical food legumes: virus diseases of economic importance and their control. Adv Virus Res 2015; 90:431-505. [PMID: 25410108 DOI: 10.1016/b978-0-12-801246-8.00009-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Diverse array of food legume crops (Fabaceae: Papilionoideae) have been adopted worldwide for their protein-rich seed. Choice of legumes and their importance vary in different parts of the world. The economically important legumes are severely affected by a range of virus diseases causing significant economic losses due to reduction in grain production, poor quality seed, and costs incurred in phytosanitation and disease control. The majority of the viruses infecting legumes are vectored by insects, and several of them are also seed transmitted, thus assuming importance in the quarantine and in the epidemiology. This review is focused on the economically important viruses of soybean, groundnut, common bean, cowpea, pigeonpea, mungbean, urdbean, chickpea, pea, faba bean, and lentil and begomovirus diseases of three minor tropical food legumes (hyacinth bean, horse gram, and lima bean). Aspects included are geographic distribution, impact on crop growth and yields, virus characteristics, diagnosis of causal viruses, disease epidemiology, and options for control. Effectiveness of selection and planting with virus-free seed, phytosanitation, manipulation of crop cultural and agronomic practices, control of virus vectors and host plant resistance, and potential of transgenic resistance for legume virus disease control are discussed.
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Affiliation(s)
- Masarapu Hema
- Department of Virology, Sri Venkateswara University, Tirupati, India
| | - Pothur Sreenivasulu
- Formerly Professor of Virology, Sri Venkateswara University, Tirupati, India
| | - Basavaprabhu L Patil
- National Research Centre on Plant Biotechnology, IARI, Pusa Campus, New Delhi, India
| | - P Lava Kumar
- International Institute of Tropical Agriculture, Ibadan, Nigeria
| | - Dodla V R Reddy
- Formerly Principal Virologist, ICRISAT, Patancheru, Hyderabad, India.
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4
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Galvez LC, Banerjee J, Pinar H, Mitra A. Engineered plant virus resistance. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 228:11-25. [PMID: 25438782 DOI: 10.1016/j.plantsci.2014.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 07/16/2014] [Accepted: 07/18/2014] [Indexed: 06/04/2023]
Abstract
Virus diseases are among the key limiting factors that cause significant yield loss and continuously threaten crop production. Resistant cultivars coupled with pesticide application are commonly used to circumvent these threats. One of the limitations of the reliance on resistant cultivars is the inevitable breakdown of resistance due to the multitude of variable virus populations. Similarly, chemical applications to control virus transmitting insect vectors are costly to the farmers, cause adverse health and environmental consequences, and often result in the emergence of resistant vector strains. Thus, exploiting strategies that provide durable and broad-spectrum resistance over diverse environments are of paramount importance. The development of plant gene transfer systems has allowed for the introgression of alien genes into plant genomes for novel disease control strategies, thus providing a mechanism for broadening the genetic resources available to plant breeders. Genetic engineering offers various options for introducing transgenic virus resistance into crop plants to provide a wide range of resistance to viral pathogens. This review examines the current strategies of developing virus resistant transgenic plants.
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Affiliation(s)
- Leny C Galvez
- Department of Plant Pathology, University of Nebarska, Lincoln, NE 68583-0722, USA
| | - Joydeep Banerjee
- Department of Plant Pathology, University of Nebarska, Lincoln, NE 68583-0722, USA
| | - Hasan Pinar
- Department of Plant Pathology, University of Nebarska, Lincoln, NE 68583-0722, USA
| | - Amitava Mitra
- Department of Plant Pathology, University of Nebarska, Lincoln, NE 68583-0722, USA.
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Kim JH, Lee JE, Kim HY. Duplex polymerase chain reaction method for detection of unapproved genetically modified tomato (Solanum lycopersicon L.) with cucumber mosaic virus (CMV) satellite RNA gene. Food Sci Biotechnol 2012. [DOI: 10.1007/s10068-012-0106-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Abstract
Cucumber mosaic virus (CMV) is an important virus because of its agricultural impact in the Mediterranean Basin and worldwide, and also as a model for understanding plant-virus interactions. This review focuses on those areas where most progress has been made over the past decade in our understanding of CMV. Clearly, a deep understanding of the role of the recently described CMV 2b gene in suppression of host RNA silencing and viral virulence is the most important discovery. These findings have had an impact well beyond the virus itself, as the 2b gene is an important tool in the studies of eukaryotic gene regulation. Protein 2b was shown to be involved in most of the steps of the virus cycle and to interfere with several basal host defenses. Progress has also been made concerning the mechanisms of virus replication and movement. However, only a few host proteins that interact with viral proteins have been identified, making this an area of research where major efforts are still needed. Another area where major advances have been made is CMV population genetics, where contrasting results were obtained. On the one hand, CMV was shown to be prone to recombination and to show high genetic diversity based on sequence data of different isolates. On the other hand, populations did not exhibit high genetic variability either within plants, or even in a field and the nearby wild plants. The situation was partially clarified with the finding that severe bottlenecks occur during both virus movement within a plant and transmission between plants. Finally, novel studies were undertaken to elucidate mechanisms leading to selection in virus population, according to the host or its environment, opening a new research area in plant-virus coevolution.
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Tan X, Zhang D, Wintgens C, Willingmann P, Adam G, Heinze C. A Comparative Testing of <i>Cucumber mosaic virus</i> (CMV)-Based Constructs to Generate Virus Resistant Plants. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/ajps.2012.34055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Increased resistance to cucumber mosaic virus (CMV) in Lilium transformed with a defective CMV replicase gene. Biotechnol Lett 2011; 33:1249-55. [PMID: 21287228 DOI: 10.1007/s10529-011-0550-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 01/18/2011] [Indexed: 10/18/2022]
Abstract
Lilium cv Acapulco was transformed with a defective cucumber mosaic virus (CMV) replicase gene (CMV2-GDD) construct using Agrobacterium tumefaciens. Four lines were analyzed for gene expression and resistance to CMV-O strain. Expression of the CMV2-GDD gene in the transgenic plants was confirmed by reverse transcription PCR (RT-PCR). When these four lines were mechanically inoculated with CMV-O, no signal of coat protein (CP) messages using RT-PCR was detected in newly produced leaves of two transgenic lines. Dot-immunobinding assay (DIBA) of CP was performed to examine the presence of the CMV in the newly produced leaves of challenged plants. Results, similar to those obtained with RT-PCR of the CP messages, were observed in DIBA. Therefore, our results imply that the two lines show increased levels of resistance to CMV, and CMV-GDD replicase gene is an effective construct that has protection against CMV in Lilium.
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Di Carli M, Villani ME, Bianco L, Lombardi R, Perrotta G, Benvenuto E, Donini M. Proteomic analysis of the plant-virus interaction in cucumber mosaic virus (CMV) resistant transgenic tomato. J Proteome Res 2010; 9:5684-97. [PMID: 20815412 DOI: 10.1021/pr100487x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cucumber mosaic virus (CMV), a member of the Cucumovirus genus, is the causal agent of several plant diseases in a wide range of host species, causing important economic losses in agriculture. Because of the lack of natural resistance genes in most crops, different genetic engineering strategies have been adopted to obtain virus-resistant plants. In a previous study, we described the engineering of transgenic tomato plants expressing a single-chain variable fragment antibody (scFv G4) that are specifically protected from CMV infection. In this work, we characterized the leaf proteome expressed during compatible plant-virus interaction in wild type and transgenic tomato. Protein changes in both inoculated and apical leaves were revealed using two-dimensional gel electrophoresis (2-DE) coupled to differential in gel electrophoresis (DIGE) technology. A total of 2084 spots were detected, and 50 differentially expressed proteins were identified by nanoscale liquid chromatographic-electrospray ionization-ion trap-tandem mass spectrometry (nLC-ESI-IT-MS/MS). The majority of these proteins were related to photosynthesis (38%), primary metabolism (18%), and defense activity (14%) and demonstrated to be actively down regulated by CMV in infected leaves. Moreover, our analysis revealed that asymptomatic apical leaves of transgenic inoculated plants had no protein profile alteration as compared to control wild type uninfected plants demonstrating that virus infection is confined to the inoculated leaves and systemic spread is hindered by the CMV coat protein (CP)-specific scFv G4 molecules. Our work is the first comparative study on compatible plant-virus interactions between engineered immunoprotected and susceptible wild type tomato plants, contributing to the understanding of antibody-mediated disease resistance mechanisms.
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Affiliation(s)
- Mariasole Di Carli
- ENEA, Centro Ricerche Casaccia, Via Anguillarese 301, I-00123, Rome, Italy.
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Zhang X, Li H, Zhang J, Zhang C, Gong P, Ziaf K, Xiao F, Ye Z. Expression of artificial microRNAs in tomato confers efficient and stable virus resistance in a cell-autonomous manner. Transgenic Res 2010; 20:569-81. [PMID: 20835923 DOI: 10.1007/s11248-010-9440-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 08/29/2010] [Indexed: 12/26/2022]
Abstract
Expression of artificial microRNAs (amiRNAs) in plants can target and degrade the invading viral RNA, consequently conferring virus resistance. Two amiRNAs, targeting the coding sequence shared by the 2a and 2b genes and the highly conserved 3' untranslated region (UTR) of Cucumber mosaic virus (CMV), respectively, were generated and introduced into the susceptible tomato. The transgenic tomato plants expressing amiRNAs displayed effective resistance to CMV infection and CMV mixed with non-targeted viruses, including tobacco mosaic virus and tomato yellow leaf curl virus. A series of grafting assays indicate scions originated from the transgenic tomato plant maintain stable resistance to CMV infection after grafted onto a CMV-infected rootstock. However, the grafting assay also suggests that the amiRNA-mediated resistance acts in a cell-autonomous manner and the amiRNA signal cannot be transmitted over long distances through the vascular system. Moreover, transgenic plants expressing amiRNA targeting the 2a and 2b viral genes displayed slightly more effective to repress CMV RNA accumulation than transgenic plants expressing amiRNA targeting the 3' UTR of viral genome did. Our work provides new evidence of the use of amiRNAs as an effective approach to engineer viral resistance in the tomato and possibly in other crops.
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Affiliation(s)
- Xiaohui Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
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Kamo K, Jordan R, Guaragna MA, Hsu HT, Ueng P. Resistance to Cucumber mosaic virus in Gladiolus plants transformed with either a defective replicase or coat protein subgroup II gene from Cucumber mosaic virus. PLANT CELL REPORTS 2010; 29:695-704. [PMID: 20411391 DOI: 10.1007/s00299-010-0855-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 03/24/2010] [Accepted: 04/07/2010] [Indexed: 05/02/2023]
Abstract
Transgenic Gladiolus plants that contain either Cucumber mosaic virus (CMV) subgroup I coat protein, CMV subgroup II coat protein, CMV replicase, a combination of the CMV subgroups I and II coat proteins, or a combination of the CMV subgroup II coat protein and replicase genes were developed. These plants were multiplied in vitro and challenged with purified CMV isolated from Gladiolus using a hand-held gene gun. Three out of 19 independently transformed plants expressing the replicase gene under control of the duplicated CaMV 35S promoter were found to be resistant to CMV subgroup I. Three out of 21 independently transformed plants with the CMV subgroup II coat protein gene under control of the Arabidopsis UBQ3 promoter were resistant to CMV subgroup II. Eighteen independently transformed plants with either the CMV subgroup I coat protein or a combination of CMV subgroups I and II coat proteins were challenged and found to be susceptible to both CMV subgroups I or II. Virus resistant plants with the CMV replicase transgene expressed much lower RNA levels than resistant plants expressing the CMV subgroup II coat protein. This work will facilitate the evaluation of virus resistance in transgenic Gladiolus plants to yield improved floral quality and productivity.
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Affiliation(s)
- Kathryn Kamo
- Floral and Nursery Plants Research Unit, USDA, US National Arboretum, Beltsville, MD, 20705, USA.
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Lin CH, Sheu F, Lin HT, Pan TM. Allergenicity assessment of genetically modified cucumber mosaic virus (CMV) resistant tomato (Solanum lycopersicon). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:2302-2306. [PMID: 20102156 DOI: 10.1021/jf903487f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Cucumber mosaic virus (CMV) has been identified as the causal agent of several disease epidemics in most countries of the world. Insect-mediated virus diseases, such as those caused by CMV, caused remarkable loss of tomato (Solanum lycopersicon) production in Taiwan. With expression of the CMV coat protein gene (Cmvcp) in a local popular tomato cultivar L4783, transgenic tomato line R8 has showed consistent CMV resistance through T(0) to T(8). In this report, the allergenicity of the CMV coat protein (CMV cp) expressed in transgenic tomato R8 was assessed by investigation of the expression of the transgene source of protein, sequence similarity with known allergens, and resistance to pepsin hydrolysis. There is no known account for either the CMV or its coat protein being an allergen. The result of a bioinformatic search also showed no significant homology between CMV cp and any known allergen. The pepsin-susceptible property of recombinant CMV cp was revealed by a simulated gastric fluid (SGF) assay. Following the most recent FAO/WHO decision tree, all results have indicated that CMV cp was a protein with low possibility to be an allergen and the transgenic tomato R8 should be considered as safe as its host.
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MESH Headings
- Amino Acid Oxidoreductases/genetics
- Animals
- Capsid Proteins/genetics
- Cucumis sativus/genetics
- Cucumis sativus/virology
- Cucumovirus/genetics
- DNA, Bacterial/genetics
- Enzyme-Linked Immunosorbent Assay
- Food, Genetically Modified
- Gene Expression Regulation, Plant
- Gene Expression Regulation, Viral
- Solanum lycopersicum/genetics
- Solanum lycopersicum/virology
- Mice
- Organisms, Genetically Modified
- Plant Diseases/genetics
- Plant Diseases/virology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/virology
- Promoter Regions, Genetic/genetics
- RNA, Messenger/genetics
- RNA, Viral/genetics
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- Chih-Hui Lin
- Institute of Microbiology and Biochemistry, College of Life Science, National Taiwan University, Taipei, Taiwan, No 1, Sec 4, Roosevelt Road, Taipei 10617, Taiwan
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Thompson JR, Tepfer M. Assessment of the Benefits and Risks for Engineered Virus Resistance. Adv Virus Res 2010; 76:33-56. [DOI: 10.1016/s0065-3527(10)76002-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Lee YH, Jung M, Shin SH, Lee JH, Choi SH, Her NH, Lee JH, Ryu KH, Paek KY, Harn CH. Transgenic peppers that are highly tolerant to a new CMV pathotype. PLANT CELL REPORTS 2009; 28:223-32. [PMID: 19018536 DOI: 10.1007/s00299-008-0637-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 10/30/2008] [Accepted: 10/30/2008] [Indexed: 05/16/2023]
Abstract
The CMV (cucumber mosaic virus) is the most frequently occurring virus in chili pepper farms. A variety of peppers that are resistant to CMVP0 were developed in the middle of 1990s through a breeding program, and commercial cultivars have since been able to control the spread of CMVP0. However, a new pathotype (CMVP1) that breaks the resistance of CMVP0-resistant peppers has recently appeared and caused a heavy loss in productivity. Since no genetic source of this new pathotype was available, a traditional breeding method cannot be used to generate a CMVP1-resistant pepper variety. Therefore, we set up a transformation system of pepper using Agrobacterium that had been transfected with the coat protein gene, CMVP0-CP, with the aim of developing a new CMVP1-resistant pepper line. A large number of transgenic peppers (T(1), T(2) and T(3)) were screened for CMVP1 tolerance using CMVP1 inoculation. Transgenic peppers tolerant to CMVP1 were selected in a plastic house as well as in the field. Three independent T(3) pepper lines highly tolerant to the CMVP1 pathogen were found to also be tolerant to the CMVP0 pathogen. These selected T(3) pepper lines were phenotypically identical or close to the non-transformed lines. However, after CMVP1 infection, the height and fruit size of the non-transformed lines became shorter and smaller, respectively, while the T(3) pepper lines maintained a normal phenotype.
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Affiliation(s)
- Yun Hee Lee
- Biotechnology Institute, Nongwoo Bio Co, Ltd, Yeoju, Gyeonggi, South Korea.
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