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Kim MH, Choi B, Jang SY, Choi JS, Kim S, Lee Y, Park S, Kwon SJ, Kang JH, Seo JK. The VP53 protein encoded by RNA2 of a fabavirus, broad bean wilt virus 2, is essential for viral systemic infection. Commun Biol 2024; 7:462. [PMID: 38627534 PMCID: PMC11021446 DOI: 10.1038/s42003-024-06170-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 04/09/2024] [Indexed: 04/19/2024] Open
Abstract
Plant viruses evolves diverse strategies to overcome the limitations of their genomic capacity and express multiple proteins, despite the constraints imposed by the host translation system. Broad bean wilt virus 2 (BBWV2) is a widespread viral pathogen, causing severe damage to economically important crops. It is hypothesized that BBWV2 RNA2 possesses two alternative in-frame translation initiation codons, resulting in the production of two largely overlapping proteins, VP53 and VP37. In this study, we aim to investigate the expression and function of VP53, an N-terminally 128-amino-acid-extended form of the viral movement protein VP37, during BBWV2 infection. By engineering various recombinant and mutant constructs of BBWV2 RNA2, here we demonstrate that VP53 is indeed expressed during BBWV2 infection. We also provide evidence of the translation of the two overlapping proteins through ribosomal leaky scanning. Furthermore, our study highlights the indispensability of VP53 for successful systemic infection of BBWV2, as its removal results in the loss of virus infectivity. These insights into the translation mechanism and functional role of VP53 during BBWV2 infection significantly contribute to our understanding of the infection mechanisms employed by fabaviruses.
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Affiliation(s)
- Myung-Hwi Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Boram Choi
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Seok-Yeong Jang
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Ji-Soo Choi
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Sora Kim
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Yubin Lee
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Suejin Park
- Department of Horticulture, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Sun-Jung Kwon
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Jin-Ho Kang
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Jang-Kyun Seo
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea.
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea.
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea.
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Kim JM, Lee JH, Park SR, Kwon JK, Ro NY, Kang BC. Molecular mapping of the broad bean wilt virus 2 resistance locus bwvr in Capsicum annuum using BSR-seq. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2024; 137:97. [PMID: 38589740 PMCID: PMC11001752 DOI: 10.1007/s00122-024-04603-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 03/16/2024] [Indexed: 04/10/2024]
Abstract
KEY MESSAGE Bulked segregant RNA seq of pools of pepper accessions that are susceptible or resistant to Broad bean wilt virus 2 identifies a gene that might confer resistance to this devastating pathogen. The single-stranded positive-sense RNA virus Broad bean wilt virus 2 (BBWV2) causes substantial damage to pepper (Capsicum annuum) cultivation. Here, we describe mapping the BBWV2 resistance locus bwvr using a F7:8 recombinant inbred line (RIL) population constructed by crossing the BBWV2-resistant pepper accession 'SNU-C' with the susceptible pepper accession 'ECW30R.' All F1 plants infected with the BBWV2 strain PAP1 were susceptible to the virus, and the RIL population showed a 1:1 ratio of resistance to susceptibility, indicating that this trait is controlled by a single recessive gene. To map bwvr, we performed bulked segregant RNA-seq (BSR-seq). We sequenced pools of resistant and susceptible lines from the RILs and aligned the reads to the high-quality 'Dempsey' reference genome to identify variants between the pools. This analysis identified 519,887 variants and selected the region from 245.9-250.8 Mb of the Dempsey reference genome as the quantitative trait locus region for bwvr. To finely map bwvr, we used newly designed high-resolution melting (HRM) and Kompetitive allele specific PCR (KASP) markers based on variants obtained from the BSR-seq reads and the PepperSNP16K array. Comparative analysis identified 11 SNU-C-specific SNPs within the bwvr locus. Using markers derived from these variants, we mapped the candidate bwvr locus to the region from 246.833-246.949 kb. SNU-C-specific variants clustered near DEM.v1.00035533 within the bwvr locus. DEM.v1.00035533 encodes the nitrate transporter NPF1.2 and contains a SNP within its 5' untranslated region. The bwvr locus, which contains four genes including DEM.v1.00035533, could represent a valuable resource for global pepper breeding programs.
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Affiliation(s)
- Jung-Min Kim
- Interdisciplinary Program in Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Joung-Ho Lee
- Department of Plant Science and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Se-Ran Park
- Department of Plant Science and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jin-Kyoung Kwon
- Department of Plant Science and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Na-Young Ro
- Rural Development Administration, National Academy of Agricultural Science, Jeonju, Republic of Korea.
| | - Byoung-Cheorl Kang
- Department of Plant Science and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
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Maina S, Norton SL, Rodoni BC. Hybrid RNA sequencing of broad bean wilt virus 2 from faba beans. Microbiol Spectr 2023; 11:e0266323. [PMID: 37823658 PMCID: PMC10714761 DOI: 10.1128/spectrum.02663-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/01/2023] [Indexed: 10/13/2023] Open
Abstract
IMPORTANCE Globally, viral diseases impair the growth and vigor of cultivated crops such as grains, leading to a significant reduction in quality, marketability, and competitiveness. As an island nation, Australia has a distinct advantage in using its border to prevent the introduction of damaging viruses, which threaten the continental agricultural sector. However, breeding programs in Australia rely on imported seeds as new sources of genetic diversity. As such, it is critical to remain vigilant in identifying new and emerging viral pathogens, by ensuring the availability of accurate genomic diagnostic tools at the grain biosecurity border. High-throughput sequencing offers game-changing opportunities in biosecurity routine testing. Genomic results are more accurate and informative compared to traditional molecular methods or biological indexing. The present work contributes to strengthening accurate phytosanitary screening, to safeguard the Australian grains industry, and expedite germplasm release to the end users.
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Affiliation(s)
- Solomon Maina
- NSW Department of Primary Industries, Biosecurity & Food Safety, Elizabeth Macarthur Agricultural Institute, Woodbridge Road, Menangle, NSW, Australia
- Australian Grains Genebank, Agriculture Victoria, Horsham, Victoria, Australia
| | - Sally L. Norton
- Australian Grains Genebank, Agriculture Victoria, Horsham, Victoria, Australia
| | - Brendan C. Rodoni
- Microbial Sciences, Pests & Diseases, Agriculture Victoria, AgriBio, Ring Road, Bundoora, Victoria, Australia
- School of Applied Systems Biology (SASB), La Trobe University, Bundoora, Victoria, Australia
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Chen C, Du M, Wang Y, Zhou X, Yang X. Molecular identification and development of an infectious cDNA clone of Trichosanthes kirilowii-infecting cucurbit mild mosaic virus. Virology 2023; 588:109891. [PMID: 37826911 DOI: 10.1016/j.virol.2023.109891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/11/2023] [Accepted: 09/25/2023] [Indexed: 10/14/2023]
Abstract
Trichosanthes kirilowii has been mainly grown for use in traditional Chinese medicine. In this study, cucurbit mild mosaic virus (CuMMV) belonging to the genus Fabavirus was identified from T. kirilowii plants. CuMMV possesses a segmented, bipartite linear single-stranded RNA genome composed of RNA1 and RNA2. Sequence analysis showed that each genomic segment shares the highest sequence similarity with those of CuMMV isolated from pumpkin. A full-length infectious cDNA clone of CuMMV was further constructed and was found to induce typical symptoms in T. kirilowii, Cucumis sativus, C. melo, Citrullus lanatus, and Cucurbita pepo. The sap inoculum derived from the infectious cDNA clone of CuMMV could be mechanically transmitted and reproduce similar symptoms in the tested plants. This is the first report on the construction of a biologically active, full-length infectious cDNA clone of CuMMV, which will provide a useful tool in understanding CuMMV-encoded proteins and plant-CuMMV interactions.
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Affiliation(s)
- Cheng Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; Institute of Plant Protection, Sichuan Academy of Agricultural Science, Key Laboratory of Integrated Pest Management on Crops in Southwest, Ministry of Agriculture, Chengdu, China
| | - Min Du
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yaqin Wang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.
| | - Xiuling Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
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Kim MH, Kwak HR, Choi B, Kwon SJ, Seo JK. Genetic plasticity in RNA2 is associated with pathogenic diversification of broad bean wilt virus 2. Virus Res 2021; 304:198533. [PMID: 34384805 DOI: 10.1016/j.virusres.2021.198533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/28/2021] [Accepted: 07/30/2021] [Indexed: 10/20/2022]
Abstract
Broad bean wilt virus 2 (BBWV2) is an evolutionarily successful RNA virus with an extensive host range and worldwide distribution that causes severe damage to crops. While numerous BBWV2 isolates from various plant species have been identified and their genome sequences determined, little information is available on the virulence and symptomatic characteristics corresponding to the genomic sequences. In this study, we provide integrated information on the molecular and pathogenic characteristics of three genetically distant BBWV2 isolates: BBWV2-PC, -LS2, and P3 obtained from Gentiana scabra, Leonurus sibiricus, and Pisum sativum, respectively. Phylogenetic and diversity analyses of the BBWV2 population included 42 isolates from various host species and revealed that RNA2 has higher genetic plasticity than RNA1 and may have evolved under host-imposed constraints. In addition, we generated an infectious cDNA clone of BBWV2-PC RNA2 (pBBWV2-PC-R2). Pseudo-recombination analysis of pBBWV2-PC-R2 further demonstrated that RNA2 determines the pathogenic characteristics of the PC isolate.
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Affiliation(s)
- Myung-Hwi Kim
- Department of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Republic of Korea; Integrated Major in Global Smart Farm, Seoul National University, Seoul 08826, Republic of Korea
| | - Hae-Ryun Kwak
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
| | - Boram Choi
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea
| | - Sun-Jung Kwon
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea
| | - Jang-Kyun Seo
- Department of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Republic of Korea; Integrated Major in Global Smart Farm, Seoul National University, Seoul 08826, Republic of Korea; Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea.
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He Z, Dong Z, Qin L, Gan H. Phylodynamics and Codon Usage Pattern Analysis of Broad Bean Wilt Virus 2. Viruses 2021; 13:v13020198. [PMID: 33525612 PMCID: PMC7912035 DOI: 10.3390/v13020198] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/19/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Broad bean wilt virus 2 (BBWV-2), which belongs to the genus Fabavirus of the family Secoviridae, is an important pathogen that causes damage to broad bean, pepper, yam, spinach and other economically important ornamental and horticultural crops worldwide. Previously, only limited reports have shown the genetic variation of BBWV2. Meanwhile, the detailed evolutionary changes, synonymous codon usage bias and host adaptation of this virus are largely unclear. Here, we performed comprehensive analyses of the phylodynamics, reassortment, composition bias and codon usage pattern of BBWV2 using forty-two complete genome sequences of BBWV-2 isolates together with two other full-length RNA1 sequences and six full-length RNA2 sequences. Both recombination and reassortment had a significant influence on the genomic evolution of BBWV2. Through phylogenetic analysis we detected three and four lineages based on the ORF1 and ORF2 nonrecombinant sequences, respectively. The evolutionary rates of the two BBWV2 ORF coding sequences were 8.895 × 10−4 and 4.560 × 10−4 subs/site/year, respectively. We found a relatively conserved and stable genomic composition with a lower codon usage choice in the two BBWV2 protein coding sequences. ENC-plot and neutrality plot analyses showed that natural selection is the key factor shaping the codon usage pattern of BBWV2. Strong correlations between BBWV2 and broad bean and pepper were observed from similarity index (SiD), codon adaptation index (CAI) and relative codon deoptimization index (RCDI) analyses. Our study is the first to evaluate the phylodynamics, codon usage patterns and adaptive evolution of a fabavirus, and our results may be useful for the understanding of the origin of this virus.
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Affiliation(s)
- Zhen He
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China; (Z.D.); (L.Q.); (H.G.)
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
- Correspondence:
| | - Zhuozhuo Dong
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China; (Z.D.); (L.Q.); (H.G.)
| | - Lang Qin
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China; (Z.D.); (L.Q.); (H.G.)
| | - Haifeng Gan
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China; (Z.D.); (L.Q.); (H.G.)
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Han SJ, Choi B, Kim MH, Kwon SJ, Kwak HR, Seo JK. Viral Strain-Specific Activation of Pathogen-Associated Molecular Pattern-Triggered Immunity Enhances Symptom Severity in Broad Bean Wilt Virus 2 Infection. FRONTIERS IN PLANT SCIENCE 2021; 12:746543. [PMID: 34721473 PMCID: PMC8549444 DOI: 10.3389/fpls.2021.746543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 08/24/2021] [Indexed: 05/22/2023]
Abstract
Broad bean wilt virus 2 (BBWV2) is an emerging virus in various economically important crops, especially pepper (Capsicum annuum L.), worldwide. Recently, the emergence of various BBWV2 strains that induce severe symptoms has increased damage to pepper crops. While the symptomatic variations among virus strains should be associated with differences in the transcriptomic reprogramming of host plants upon infection, underlying molecular mechanisms and associated genes are largely unknown. In the present study, we employed transcriptome analysis to identify responsible host factors for symptom enhancement in the BBWV2-pepper pathosystem using two distinct BBWV2 strains, PAP1 (a severe strain) and RP1 (a mild strain). Comparative analysis of the differentially expressed genes (DEGs) revealed that various genes associated with pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and ethylene signaling were significantly upregulated upon infection with the severe PAP1 strain, but not with the mild RP1 strain. Indeed, hormone analysis revealed that ethylene emission was significantly increased in pepper plants infected with PAP1. These observations imply that the activation of the PTI-associated defense responses reinforce symptom formation during BBWV2 infection in a virus strain-specific manner.
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Affiliation(s)
- Soo-Jung Han
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, South Korea
| | - Boram Choi
- Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea
| | - Myung-Hwi Kim
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, South Korea
- Integrated Major in Global Smart Farm, Seoul National University, Seoul, South Korea
| | - Sun-Jung Kwon
- Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea
| | - Hae-Ryun Kwak
- Crop Protection Division, Rural Development Administration, National Institute of Agricultural Sciences, Wanju, South Korea
| | - Jang-Kyun Seo
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, South Korea
- Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea
- Integrated Major in Global Smart Farm, Seoul National University, Seoul, South Korea
- *Correspondence: Jang-Kyun Seo,
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Heo KJ, Kwon SJ, Kim MK, Kwak HR, Han SJ, Kwon MJ, Rao ALN, Seo JK. Newly emerged resistance-breaking variants of cucumber mosaic virus represent ongoing host-interactive evolution of an RNA virus. Virus Evol 2020; 6:veaa070. [PMID: 33240527 PMCID: PMC7673075 DOI: 10.1093/ve/veaa070] [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] [Indexed: 12/16/2022] Open
Abstract
Understanding the evolutionary history of a virus and the mechanisms influencing the direction of its evolution is essential for the development of more durable strategies to control the virus in crop fields. While the deployment of host resistance in crops is the most efficient means to control various viruses, host resistance itself can act as strong selective pressure and thus play a critical role in the evolution of virus virulence. Cucumber mosaic virus (CMV), a plant RNA virus with high evolutionary capacity, has caused endemic disease in various crops worldwide, including pepper (Capsicum annuum L.), because of frequent emergence of resistance-breaking variants. In this study, we examined the molecular and evolutionary characteristics of recently emerged, resistance-breaking CMV variants infecting pepper. Our population genetics analysis revealed that the high divergence capacity of CMV RNA1 might have played an essential role in the host-interactive evolution of CMV and in shaping the CMV population structure in pepper. We also demonstrated that nonsynonymous mutations in RNA1 encoding the 1a protein enabled CMV to overcome the deployed resistance in pepper. Our findings suggest that resistance-driven selective pressures on RNA1 might have contributed in shaping the unique evolutionary pattern of CMV in pepper. Therefore, deployment of a single resistance gene may reduce resistance durability against CMV and more integrated approaches are warranted for successful control of CMV in pepper.
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Affiliation(s)
| | - Sun-Jung Kwon
- Institutes of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-ro, Pyeongchang 25354, Republic of Korea
| | - Mi-Kyeong Kim
- Department of Plant Medicine, Chungbuk National University, 1 Chungdae-ro, Cheongju 28644, Republic of Korea
| | - Hae-Ryun Kwak
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, 300 Nongsaengmyeong-ro, Wanju 55365, Republic of Korea
| | - Soo-Jung Han
- Department of International Agricultural Technology
| | - Min-Jun Kwon
- Department of International Agricultural Technology
| | - A L N Rao
- Department of Microbiology and Plant Pathology, University of California, Boyce Hall 1463, 900 University Ave, Riverside, CA 92521, USA
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Chabi-Jesus C, Ramos-González PL, Tassi AD, Guerra-Peraza O, Kitajima EW, Harakava R, Beserra JEA, Salaroli RB, Freitas-Astúa J. Identification and Characterization of Citrus Chlorotic Spot Virus, a New Dichorhavirus Associated with Citrus Leprosis-Like Symptoms. PLANT DISEASE 2018; 102:1588-1598. [PMID: 30673423 DOI: 10.1094/pdis-09-17-1425-re] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Local chlorotic spots resembling early lesions characteristic of citrus leprosis (CL) were observed in leaves of two sweet orange (Citrus sinensis L.) trees in Teresina, State of Piauí, Brazil, in early 2017. However, despite the similarities, these spots were generally larger than those of a typical CL and showed rare or no necrosis symptoms. In symptomatic tissues, transmission electron microscopy revealed the presence of viroplasms in the nuclei of the infected parenchymal cells and rod-shaped particles with an average size of approximately 40 × 100 nm, resembling those typically observed during infection by dichorhaviruses. A bipartite genome of the putative novel virus, tentatively named citrus chlorotic spot virus (CiCSV) (RNA1 = 6,518 nucleotides [nt] and RNA2 = 5,987 nt), revealed the highest nucleotide sequence identity values with the dichorhaviruses coffee ringspot virus strain Lavras (73.8%), citrus leprosis virus N strain Ibi1 (58.6%), and orchid fleck virus strain So (56.9%). In addition to citrus, CiCSV was also found in local chlorotic lesions on leaves of the ornamental plant beach hibiscus (Talipariti tiliaceum (L.) Fryxell). Morphological characterization of mites recovered from the infected plants revealed at least two different types of Brevipalpus. One of them corresponds to Brevipalpus yothersi. The other is slightly different from B. yothersi mites but comprises traits that possibly place it as another species. A mix of the two mite types collected on beach hibiscus successfully transmitted CiCSV to arabidopsis plants but additional work is required to verify whether both types of flat mite may act as viral vectors. The current study reveals a newly described dichorhavirus associated with a citrus disease in the northeastern region of Brazil.
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Affiliation(s)
- C Chabi-Jesus
- Instituto Biológico, São Paulo, SP, Brazil; and PPG Microbiologia Agrícola ESALQ/USP, Piracicaba, SP, Brazil
| | | | - A D Tassi
- LFN/ESALQ/USP, 13418-900 Piracicaba, SP, Brazil
| | - O Guerra-Peraza
- Instituto Biológico, São Paulo; and Citrus Research & Education Center, University of Florida
| | | | | | | | | | - J Freitas-Astúa
- Instituto Biológico, São Paulo; and Embrapa Mandioca e Fruticultura, Cruz das Almas, BA, Brazil
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Seo JK, Kwak HR, Choi B, Han SJ, Kim MK, Choi HS. Movement protein of broad bean wilt virus 2 serves as a determinant of symptom severity in pepper. Virus Res 2017; 242:141-145. [PMID: 28970056 DOI: 10.1016/j.virusres.2017.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 09/27/2017] [Accepted: 09/29/2017] [Indexed: 10/18/2022]
Abstract
Broad bean wilt virus 2 (BBWV2, genus Fabavirus, family Secoviridae) has a wide host range and infects many economically important crops. Various isolates of BBWV2 have been identified from diverse host plants, and their molecular and biological characteristics have been investigated. In our previous study, we demonstrated that BBWV2 RNA2 contains a symptom determinant(s) capable of enhancing symptom severity by utilizing infectious full-length cDNA clones of two distinct strains of BBWV2, pBBWV2-PAP1 (a severe strain) and pBBWV2-RP1 (a mild strain). In the present study, to identify the symptom determinant(s) of BBWV2, we exploited disease responses of pBBWV2-PAP1- and pBBWV2-RP1-derived chimeric viruses and amino acid substitution mutant viruses in Nicotiana benthamiana and pepper (Capsicum annuum Quarri) and demonstrated that the movement protein (MP) encoded in BBWV RNA2 is the determinant of disease symptom severity in both plants. A single amino acid substitution in the MP was sufficient for changing symptom severity of BBWV2. Our finding provides a role for the MP as a symptom determinant in BBWV2 and increases the understanding of the basis of molecular interactions between host plants and BBWV2.
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Affiliation(s)
- Jang-Kyun Seo
- Department of International Agricultural Technology and Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea.
| | - Hae-Ryun Kwak
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
| | - Boram Choi
- Department of International Agricultural Technology and Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea
| | - Soo-Jung Han
- Department of International Agricultural Technology and Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea
| | - Mi-Kyeong Kim
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
| | - Hong-Soo Choi
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
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