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Rede JE, Breitbart M, Lundquist C, Nagasaki K, Hewson I. Diverse RNA viruses discovered in multiple seagrass species. PLoS One 2024; 19:e0302314. [PMID: 39196976 PMCID: PMC11356395 DOI: 10.1371/journal.pone.0302314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 04/01/2024] [Indexed: 08/30/2024] Open
Abstract
Seagrasses are marine angiosperms that form highly productive and diverse ecosystems. These ecosystems, however, are declining worldwide. Plant-associated microbes affect critical functions like nutrient uptake and pathogen resistance, which has led to an interest in the seagrass microbiome. However, despite their significant role in plant ecology, viruses have only recently garnered attention in seagrass species. In this study, we produced original data and mined publicly available transcriptomes to advance our understanding of RNA viral diversity in Zostera marina, Zostera muelleri, Zostera japonica, and Cymodocea nodosa. In Z. marina, we present evidence for additional Zostera marina amalgavirus 1 and 2 genotypes, and a complete genome for an alphaendornavirus previously evidenced by an RNA-dependent RNA polymerase gene fragment. In Z. muelleri, we present evidence for a second complete alphaendornavirus and near complete furovirus. Both are novel, and, to the best of our knowledge, this marks the first report of a furovirus infection naturally occurring outside of cereal grasses. In Z. japonica, we discovered genome fragments that belong to a novel strain of cucumber mosaic virus, a prolific pathogen that depends largely on aphid vectoring for host-to-host transmission. Lastly, in C. nodosa, we discovered two contigs that belong to a novel virus in the family Betaflexiviridae. These findings expand our knowledge of viral diversity in seagrasses and provide insight into seagrass viral ecology.
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Affiliation(s)
- Jordan E. Rede
- Department of Microbiology, Cornell University, Ithaca, NY, United States of America
| | - Mya Breitbart
- College of Marine Science, University of South Florida, Saint Petersburg, FL, United States of America
| | - Carolyn Lundquist
- National Institute of Water and Atmospheric Research, Hamilton, New Zealand
- School of Environment, The University of Auckland, Auckland, New Zealand
| | - Keizo Nagasaki
- Faculty of Science and Technology, Kochi University, Nankoku, Kochi, Japan
| | - Ian Hewson
- Department of Microbiology, Cornell University, Ithaca, NY, United States of America
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2
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Qiao Z, Wang J, Huang K, Hu H, Gu Z, Liao Q, Du Z. The non-template functions of helper virus RNAs create optimal replication conditions to enhance the proliferation of satellite RNAs. PLoS Pathog 2024; 20:e1012174. [PMID: 38630801 PMCID: PMC11057728 DOI: 10.1371/journal.ppat.1012174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 04/29/2024] [Accepted: 04/07/2024] [Indexed: 04/19/2024] Open
Abstract
As a type of parasitic agent, satellite RNAs (satRNAs) rely on cognate helper viruses to achieve their replication and transmission. During the infection of satRNAs, helper virus RNAs serve as templates for synthesizing viral proteins, including the replication proteins essential for satRNA replication. However, the role of non-template functions of helper virus RNAs in satRNA replication remains unexploited. Here we employed the well-studied model that is composed of cucumber mosaic virus (CMV) and its associated satRNA. In the experiments employing the CMV trans-replication system, we observed an unexpected phenomenon the replication proteins of the mild strain LS-CMV exhibited defective in supporting satRNA replication, unlike those of the severe strain Fny-CMV. Independent of translation products, all CMV genomic RNAs could enhance satRNA replication, when combined with the replication proteins of CMV. This enhancement is contingent upon the recruitment and complete replication of helper virus RNAs. Using the method developed for analyzing the satRNA recruitment, we observed a markedly distinct ability of the replication proteins from both CMV strains to recruit the positive-sense satRNA-harboring RNA3 mutant for replication. This is in agreement with the differential ability of both 1a proteins in binding satRNAs in plants. The discrepancies provide a convincing explanation for the variation of the replication proteins of both CMV strains in replicating satRNAs. Taken together, our work provides compelling evidence that the non-template functions of helper virus RNAs create an optimal replication environment to enhance satRNA proliferation.
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Affiliation(s)
- Zimu Qiao
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Jin Wang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Kaiyun Huang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Honghao Hu
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Zhouhang Gu
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Qiansheng Liao
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
| | - Zhiyou Du
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China
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3
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Palukaitis P, Yoon JY. Defense signaling pathways in resistance to plant viruses: Crosstalk and finger pointing. Adv Virus Res 2024; 118:77-212. [PMID: 38461031 DOI: 10.1016/bs.aivir.2024.01.002] [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] [Indexed: 03/11/2024]
Abstract
Resistance to infection by plant viruses involves proteins encoded by plant resistance (R) genes, viz., nucleotide-binding leucine-rich repeats (NLRs), immune receptors. These sensor NLRs are activated either directly or indirectly by viral protein effectors, in effector-triggered immunity, leading to induction of defense signaling pathways, resulting in the synthesis of numerous downstream plant effector molecules that inhibit different stages of the infection cycle, as well as the induction of cell death responses mediated by helper NLRs. Early events in this process involve recognition of the activation of the R gene response by various chaperones and the transport of these complexes to the sites of subsequent events. These events include activation of several kinase cascade pathways, and the syntheses of two master transcriptional regulators, EDS1 and NPR1, as well as the phytohormones salicylic acid, jasmonic acid, and ethylene. The phytohormones, which transit from a primed, resting states to active states, regulate the remainder of the defense signaling pathways, both directly and by crosstalk with each other. This regulation results in the turnover of various suppressors of downstream events and the synthesis of various transcription factors that cooperate and/or compete to induce or suppress transcription of either other regulatory proteins, or plant effector molecules. This network of interactions results in the production of defense effectors acting alone or together with cell death in the infected region, with or without the further activation of non-specific, long-distance resistance. Here, we review the current state of knowledge regarding these processes and the components of the local responses, their interactions, regulation, and crosstalk.
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Affiliation(s)
- Peter Palukaitis
- Graduate School of Plant Protection and Quarantine, Jeonbuk National University, Jeonju, Jeollabuk-do, Republic of Korea.
| | - Ju-Yeon Yoon
- Graduate School of Plant Protection and Quarantine, Jeonbuk National University, Jeonju, Jeollabuk-do, Republic of Korea.
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4
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Zhang K, Li W, Li H, Luo Y, Li Z, Wang X, Chen X. A Leaf-Patchable Reflectance Meter for In Situ Continuous Monitoring of Chlorophyll Content. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2305552. [PMID: 37797172 PMCID: PMC10724420 DOI: 10.1002/advs.202305552] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Indexed: 10/07/2023]
Abstract
Plant wearable sensors facilitate the real-time monitoring of plant physiological status. In situ monitoring of the plant chlorophyll content over days can provide valuable information on the photosynthetic capacity, nitrogen content, and general plant health. However, it cannot be achieved by current chlorophyll measuring methods. Here, a miniaturized and plant-wearable chlorophyll meter for rapid, non-destructive, in situ, and long-term chlorophyll monitoring is developed. The reflectance-based chlorophyll sensor with 1.5 mm thickness and 0.2 g weight (1000 times lighter than the commercial chlorophyll meter), includes a light emitting diode (LED) and two symmetric photodetectors (PDs) on a flexible substrate, and is patched onto the leaf upper epidermis with a conformal light guiding layer. A chlorophyll content index (CCI) calculated based on the sensor shows a better linear relationship with the leaf chlorophyll content (r2 > 0.9) than the traditional chlorophyll meter. This meter can wirelessly communicate with a smartphone to monitor the leaf chlorophyll change under various stresses and indicate the unhealthy status of plants for long-term application of plants under various stresses earlier than chlorophyll meter and naked-eye observation. This wearable chlorophyll sensing patch is promising in smart and precision agriculture.
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Affiliation(s)
- Kaiyi Zhang
- Innovative Center for Flexible Devices (iFLEX)School of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore
| | - Wenlong Li
- Institute of Materials Research and Engineering (IMRE)Agency for Science, Technology and Research (A*STAR)2 Fusionopolis Way, Innovis #08‐03Singapore138634Republic of Singapore
| | - Haicheng Li
- Innovative Center for Flexible Devices (iFLEX)School of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore
| | - Yifei Luo
- Institute of Materials Research and Engineering (IMRE)Agency for Science, Technology and Research (A*STAR)2 Fusionopolis Way, Innovis #08‐03Singapore138634Republic of Singapore
| | - Zheng Li
- Innovative Center for Flexible Devices (iFLEX)School of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore
| | - Xiaoshi Wang
- Innovative Center for Flexible Devices (iFLEX)School of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore
| | - Xiaodong Chen
- Innovative Center for Flexible Devices (iFLEX)School of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore
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5
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Kwon MJ, Kwon SJ, Kim MH, Choi B, Byun HS, Kwak HR, Seo JK. Visual tracking of viral infection dynamics reveals the synergistic interactions between cucumber mosaic virus and broad bean wilt virus 2. Sci Rep 2023; 13:7261. [PMID: 37142679 PMCID: PMC10160061 DOI: 10.1038/s41598-023-34553-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 05/03/2023] [Indexed: 05/06/2023] Open
Abstract
Cucumber mosaic virus (CMV) is one of the most prevalent plant viruses in the world, and causes severe damage to various crops. CMV has been studied as a model RNA virus to better understand viral replication, gene functions, evolution, virion structure, and pathogenicity. However, CMV infection and movement dynamics remain unexplored due to the lack of a stable recombinant virus tagged with a reporter gene. In this study, we generated a CMV infectious cDNA construct tagged with a variant of the flavin-binding LOV photoreceptor (iLOV). The iLOV gene was stably maintained in the CMV genome after more than four weeks of three serial passages between plants. Using the iLOV-tagged recombinant CMV, we visualized CMV infection and movement dynamics in living plants in a time course manner. We also examined whether CMV infection dynamics is influenced by co-infection with broad bean wilt virus 2 (BBWV2). Our results revealed that no spatial interference occurred between CMV and BBWV2. Specifically, BBWV2 facilitated the cell-to-cell movement of CMV in the upper young leaves. In addition, the BBWV2 accumulation level increased after co-infection with CMV.
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Affiliation(s)
- Min-Jun Kwon
- Department of International Agricultural 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
| | - 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
| | - Hee-Seong Byun
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, 55365, Republic of Korea
| | - Hae-Ryun Kwak
- Crop Protection Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, 55365, Republic of Korea
| | - Jang-Kyun Seo
- Department of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea.
- Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea.
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, Republic of Korea.
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6
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Zhang X, Wang X, Xu K, Jiang Z, Dong K, Xie X, Zhang H, Yue N, Zhang Y, Wang XB, Han C, Yu J, Li D. The serine/threonine/tyrosine kinase STY46 defends against hordeivirus infection by phosphorylating γb protein. PLANT PHYSIOLOGY 2021; 186:715-730. [PMID: 33576790 PMCID: PMC8154058 DOI: 10.1093/plphys/kiab056] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 01/21/2021] [Indexed: 05/05/2023]
Abstract
Protein phosphorylation is a common post-translational modification that frequently occurs during plant-virus interaction. Host protein kinases often regulate virus infectivity and pathogenicity by phosphorylating viral proteins. The Barley stripe mosaic virus (BSMV) γb protein plays versatile roles in virus infection and the coevolutionary arms race between plant defense and viral counter-defense. Here, we identified that the autophosphorylated cytosolic serine/threonine/tyrosine (STY) protein kinase 46 of Nicotiana benthamiana (NbSTY46) phosphorylates and directly interacts with the basic motif domain (aa 19-47) of γb in vitro and in vivo. Overexpression of wild-type NbSTY46, either transiently or transgenically, suppresses BSMV replication and ameliorates viral symptoms, whereas silencing of NbSTY46 leads to increased viral replication and exacerbated symptom. Moreover, the antiviral role of NbSTY46 requires its kinase activity, as the NbSTY46T436A mutant, lacking kinase activity, not only loses the ability to phosphorylate and interact with γb but also fails to impair BSMV infection when expressed in plants. NbSTY46 could also inhibit the replication of Lychnis ringspot virus, another chloroplast-replicating hordeivirus. In summary, we report a function of the cytosolic kinase STY46 in defending against plant viral infection by phosphorylating a viral protein in addition to its basal function in plant growth, development, and abiotic stress responses.
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Affiliation(s)
- Xuan Zhang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xueting Wang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Kai Xu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China
| | - Zhihao Jiang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Kai Dong
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Xialin Xie
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - He Zhang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Ning Yue
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yongliang Zhang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Xian-Bing Wang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Chenggui Han
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Jialin Yu
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Dawei Li
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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7
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Sudhakaran S, Thakral V, Padalkar G, Rajora N, Dhiman P, Raturi G, Sharma Y, Tripathi DK, Deshmukh R, Sharma TR, Sonah H. Significance of solute specificity, expression, and gating mechanism of tonoplast intrinsic protein during development and stress response in plants. PHYSIOLOGIA PLANTARUM 2021; 172:258-274. [PMID: 33723851 DOI: 10.1111/ppl.13386] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/01/2021] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
Tonoplast intrinsic proteins (TIPs), belonging to the aquaporin family, are transmembrane channels located mostly at the tonoplast of plant cells. The TIPs are known to transport water and many other small solutes such as ammonia, urea, hydrogen peroxide, and glycerol. In the present review, phylogenetic distribution, structure, transport dynamics, gating mechanism, sub-cellular localization, tissue-specific expression, and co-expression of TIPs are discussed to define their versatile role in plants. Based on the phylogenetic distribution, TIPs are classified into five distinct groups with aromatic-arginine (Ar/R) selectivity filters, typical pore-morphology, and tissue-specific gene expression patterns. The tissue-specific expression of TIPs is conserved among diverse plant species, more particularly for TIP3s, which are expressed exclusively in seeds. Studying TIP3 evolution will help to understand seed development and germination. The solute specificity of TIPs plays an imperative role in physiological processes like stomatal movement and vacuolar sequestration as well as in alleviating environmental stress. TIPs also play an important role in growth and developmental processes like radicle protrusion, anther dehiscence, seed germination, cell elongation, and expansion. The gating mechanism of TIPs regulates the solute flow in response to external signals, which helps to maintain the physiological functions of the cell. The information provided in this review is a base to explore TIP's potential in crop improvement programs.
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Affiliation(s)
- Sreeja Sudhakaran
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Vandana Thakral
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Gunashri Padalkar
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Nitika Rajora
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Pallavi Dhiman
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Gaurav Raturi
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Yogesh Sharma
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Durgesh K Tripathi
- Amity Institute of Organic Agriculture (AIOA), Amity University Uttar Pradesh, Noida, India
| | - Rupesh Deshmukh
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Tilak Raj Sharma
- Division of Crop Science, Indian Council of Agricultural Research, New Delhi, India
| | - Humira Sonah
- Division of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
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Yoon JY, Palukaitis P. Cucumber Mosaic Virus 1a Protein Interacts with the Tobacco SHE1 Transcription Factor and Partitions between the Nucleus and the Tonoplast Membrane. THE PLANT PATHOLOGY JOURNAL 2021; 37:182-193. [PMID: 33866760 PMCID: PMC8053847 DOI: 10.5423/ppj.ft.03.2021.0045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 03/14/2021] [Indexed: 06/12/2023]
Abstract
The transcription factor SHE1 was identified as an interacting partner with the cucumber mosaic virus (CMV) 1a protein in the yeast two-hybrid system, by a pull-down assay, and via bimolecular fluorescent complementation. Using fluorescent-tagged proteins and confocal microscopy, the CMV 1a protein itself was found distributed predominantly between the nucleus and the tonoplast membrane, although it was also found in speckles in the cytoplasm. The SHE1 protein was localized in the nucleus, but in the presence of the CMV 1a protein was partitioned between the nucleus and the tonoplast membrane. SHE1 expression was induced by infection of tobacco with four tested viruses: CMV, tobacco mosaic virus, potato virus X and potato virus Y. Transgenic tobacco expressing the CMV 1a protein showed constitutive expression of SHE1, indicating that the CMV 1a protein may be responsible for its induction. However, previously, such plants also were shown to have less resistance to local and systemic movement of tobacco mosaic virus (TMV) expressing the green fluorescent protein, suggesting that the CMV 1a protein may act to prevent the function of the SHE1 protein. SHE1 is a member of the AP2/ERF class of transcription factors and is conserved in sequence in several Nicotiana species, although two clades of SHE1 could be discerned, including both different Nicotiana species and cultivars of tobacco, varying by the presence of particular insertions or deletions.
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Affiliation(s)
- Ju-Yeon Yoon
- Virology Unit, Division of Horticultural and Herbal Crop Environment, National Institute of Horticultural and Herbal Science, Rural Development Administration, Wanju 55365,
Korea
| | - Peter Palukaitis
- Department of Horticulture Sciences, Seoul Women's University, Seoul 01797,
Korea
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Abstract
RNAscope has been recently introduced by Advanced Cell Diagnostics (Newark, CA, USA) for in situ hybridization (ISH) of target RNAs using a proprietary technology for probe design and hybridization assay. The method has been extensively used as a basis for sensitive diagnostic assays in the medical field, while applications of this technique in plant sciences are still rare. Here, we describe a multiplex ISH protocol for detection of two plant viruses in formalin-fixed paraffin-embedded tissue sections from cassava. The dual-color protocol described can be used as reference for virus/host interaction studies including the visualization of virus nucleic acids and plant endogenous mRNAs. RNAscope provides a specificity and sensitivity of target detection that otherwise cannot be reached.
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10
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Soltani N, Staton M, Gwinn KD. Response of bitter and sweet Chenopodium quinoa varieties to cucumber mosaic virus: Transcriptome and small RNASeq perspective. PLoS One 2021; 16:e0244364. [PMID: 33621238 PMCID: PMC7901783 DOI: 10.1371/journal.pone.0244364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/08/2020] [Indexed: 12/25/2022] Open
Abstract
Saponins are secondary metabolites with antiviral properties. Low saponin (sweet) varieties of quinoa (Chenopodium quinoa) have been developed because seeds high in saponins taste bitter. The aim of this study was to elucidate the role of saponin in resistance of quinoa to Cucumber mosaic virus (CMV). Differential gene expression was studied in time-series study of CMV infection. High-throughput transcriptome sequence data were obtained from 36 samples (3 varieties × +/- CMV × 1 or 4 days after inoculation × 3 replicates). Translation, lipid, nitrogen, amino acid metabolism, and mono- and sesquiterpenoid biosynthesis genes were upregulated in CMV infections. In 'Red Head' (bitter), CMV-induced systemic symptoms were concurrent with downregulation of a key saponin biosynthesis gene, TSARL1, four days after inoculation. In local lesion responses (sweet and semi-sweet), TSARL1 levels remained up-regulated. Known microRNAs (miRNA) (81) from 11 miR families and 876 predicted novel miRNAs were identified. Differentially expressed miRNA and short interfering RNA clusters (24nt) induced by CMV infection are predicted to target genomic and intergenic regions enriched in repetitive elements. This is the first report of integrated RNASeq and sRNASeq data in quinoa-virus interactions and provides comprehensive understanding of involved genes, non-coding regions, and biological pathways in virus resistance.
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Affiliation(s)
- Nourolah Soltani
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
- Department of Plant Pathology, University of California-Davis, Davis, California, United States of America
| | - Margaret Staton
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Kimberly D. Gwinn
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
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11
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Wang X, Ma J, Jin X, Yue N, Gao P, Mai KKK, Wang XB, Li D, Kang BH, Zhang Y. Three-dimensional reconstruction and comparison of vacuolar membranes in response to viral infection. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:353-364. [PMID: 33085164 DOI: 10.1111/jipb.13027] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
The vacuole is a unique plant organelle that plays an important role in maintaining cellular homeostasis under various environmental stress conditions. However, the effects of biotic stress on vacuole structure has not been examined using three-dimensional (3D) visualization. Here, we performed 3D electron tomography to compare the ultrastructural changes in the vacuole during infection with different viruses. The 3D models revealed that vacuoles are remodeled in cells infected with cucumber mosaic virus (CMV) or tobacco necrosis virus A Chinese isolate (TNV-AC ), resulting in the formation of spherules at the periphery of the vacuole. These spherules contain neck-like channels that connect their interior with the cytosol. Confocal microscopy of CMV replication proteins 1a and 2a and TNV-AC auxiliary replication protein p23 showed that all of these proteins localize to the tonoplast. Electron microscopy revealed that the expression of these replication proteins alone is sufficient to induce spherule formation on the tonoplast, suggesting that these proteins play prominent roles in inducing vacuolar membrane remodeling. This is the first report of the 3D structures of viral replication factories built on the tonoplasts. These findings contribute to our understanding of vacuole biogenesis under normal conditions and during assembly of plant (+) RNA virus replication complexes.
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Affiliation(s)
- Xueting Wang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Juncai Ma
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Xuejiao Jin
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Ning Yue
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Peng Gao
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Keith Ka Ki Mai
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Xian-Bing Wang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Dawei Li
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Byung-Ho Kang
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Yongliang Zhang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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Watt LG, Crawshaw S, Rhee SJ, Murphy AM, Canto T, Carr JP. The cucumber mosaic virus 1a protein regulates interactions between the 2b protein and ARGONAUTE 1 while maintaining the silencing suppressor activity of the 2b protein. PLoS Pathog 2020; 16:e1009125. [PMID: 33270799 PMCID: PMC7738167 DOI: 10.1371/journal.ppat.1009125] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 12/15/2020] [Accepted: 11/04/2020] [Indexed: 12/30/2022] Open
Abstract
The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) is a potent counter-defense and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. It also disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). But in Arabidopsis thaliana complete inhibition of AGO1 is counterproductive to CMV since this triggers another layer of antiviral silencing mediated by AGO2, de-represses strong resistance against aphids (the insect vectors of CMV), and exacerbates symptoms. Using confocal laser scanning microscopy, bimolecular fluorescence complementation, and co-immunoprecipitation assays we found that the CMV 1a protein, a component of the viral replicase complex, regulates the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in P-bodies, the 1a protein limits the proportion of 2b protein molecules available to bind AGO1, which ameliorates 2b-induced disease symptoms, and moderates induction of resistance to CMV and to its aphid vector. However, the 1a protein-2b protein interaction does not inhibit the ability of the 2b protein to inhibit silencing of reporter gene expression in agroinfiltration assays. The interaction between the CMV 1a and 2b proteins represents a novel regulatory system in which specific functions of a VSR are selectively modulated by another viral protein. The finding also provides a mechanism that explains how CMV, and possibly other viruses, modulates symptom induction and manipulates host-vector interactions.
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Affiliation(s)
- Lewis G. Watt
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sam Crawshaw
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sun-Ju Rhee
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alex M. Murphy
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Tomás Canto
- Department of Microbial and Plant Biotechnology, Center for Biological Research, Madrid, Spain
| | - John P. Carr
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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Tungadi T, Donnelly R, Qing L, Iqbal J, Murphy AM, Pate AE, Cunniffe NJ, Carr JP. Cucumber mosaic virus 2b proteins inhibit virus-induced aphid resistance in tobacco. MOLECULAR PLANT PATHOLOGY 2020; 21:250-257. [PMID: 31777194 PMCID: PMC6988427 DOI: 10.1111/mpp.12892] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Cucumber mosaic virus (CMV), which is vectored by aphids, has a tripartite RNA genome encoding five proteins. In tobacco (Nicotiana tabacum), a subgroup IA CMV strain, Fny-CMV, increases plant susceptibility to aphid infestation but a viral mutant unable to express the 2b protein (Fny-CMV∆2b) induces aphid resistance. We hypothesized that in tobacco, one or more of the four other Fny-CMV gene products (the 1a or 2a replication proteins, the movement protein, or the coat protein) are potential aphid resistance elicitors, whilst the 2b protein counteracts induction of aphid resistance. Mutation of the Fny-CMV 2b protein indicated that inhibition of virus-induced resistance to aphids (Myzus persicae) depends on amino acid sequences known to control nucleus-to-cytoplasm shuttling. LS-CMV (subgroup II) also increased susceptibility to aphid infestation but the LS-CMV∆2b mutant did not induce aphid resistance. Using reassortant viruses comprising different combinations of LS and Fny genomic RNAs, we showed that Fny-CMV RNA 1 but not LS-CMV RNA 1 conditions aphid resistance in tobacco, suggesting that the Fny-CMV 1a protein triggers resistance. However, the 2b proteins of both strains suppress aphid resistance, suggesting that the ability of 2b proteins to inhibit aphid resistance is conserved among divergent CMV strains.
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Affiliation(s)
- Trisna Tungadi
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Ruairí Donnelly
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Ling Qing
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
- College of Plant ProtectionSouthwest UniversityNo. 2, Tiansheng RoadChongqingChina
| | - Javaid Iqbal
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Alex M. Murphy
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Adrienne E. Pate
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Nik J. Cunniffe
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - John P. Carr
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
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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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Salánki K, Gellért Á, Nemes K, Divéki Z, Balázs E. Molecular Modeling for Better Understanding of Cucumovirus Pathology. Adv Virus Res 2018; 102:59-88. [PMID: 30266176 DOI: 10.1016/bs.aivir.2018.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Cucumber mosaic virus (CMV) is a small RNA virus capable of infecting a wide variety of plant species. The high economic losses due to the CMV infection made this virus a relevant subject of scientific studies, which were further facilitated by the small size of the viral genome. Hence, CMV also became a model organism to investigate the molecular mechanism of pathogenesis. All viral functions are dependent on intra- and intermolecular interactions between nucleic acids and proteins of the virus and the host. This review summarizes the recent data on molecular determinants of such interactions. A particular emphasis is given to the results obtained by utilizing molecular-based planning and modeling techniques.
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Affiliation(s)
- Katalin Salánki
- MTA ATK, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Ákos Gellért
- MTA ATK, Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Katalin Nemes
- MTA ATK, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Zoltán Divéki
- MTA ATK, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Ervin Balázs
- MTA ATK, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary.
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Munganyinka E, Margaria P, Sheat S, Ateka EM, Tairo F, Ndunguru J, Winter S. Localization of cassava brown streak virus in Nicotiana rustica and cassava Manihot esculenta (Crantz) using RNAscope® in situ hybridization. Virol J 2018; 15:128. [PMID: 30107851 PMCID: PMC6092782 DOI: 10.1186/s12985-018-1038-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 08/02/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Cassava brown streak disease (CBSD) has a viral aetiology and is caused by viruses belonging to the genus Ipomovirus (family Potyviridae), Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Molecular and serological methods are available for detection, discrimination and quantification of cassava brown streak viruses (CBSVs) in infected plants. However, precise determination of the viral RNA localization in infected host tissues is still not possible pending appropriate methods. RESULTS We have developed an in situ hybridization (ISH) assay based on RNAscope® technology that allows the sensitive detection and localization of CBSV RNA in plant tissues. The method was initially developed in the experimental host Nicotiana rustica and was then further adapted to cassava. Highly sensitive and specific detection of CBSV RNA was achieved without background and hybridization signals in sections prepared from non-infected tissues. The tissue tropism of CBSV RNAs appeared different between N. rustica and cassava. CONCLUSIONS This study provides a robust method for CBSV detection in the experimental host and in cassava. The protocol will be used to study CBSV tropism in various cassava genotypes, as well as CBSVs/cassava interactions in single and mixed infections.
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Affiliation(s)
- Esperance Munganyinka
- Rwanda Agriculture Board, P.O. Box 5016, Kigali, Rwanda
- Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi, Kenya
| | - Paolo Margaria
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Plant Virus Department, Messeweg 11/12, 38104 Braunschweig, Germany
| | - Samar Sheat
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Plant Virus Department, Messeweg 11/12, 38104 Braunschweig, Germany
| | - Elijah M. Ateka
- Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi, Kenya
| | - Fred Tairo
- Mikocheni Agricultural Research Institute, P.O. Box 6226, Dar es Salaam, Tanzania
| | - Joseph Ndunguru
- Mikocheni Agricultural Research Institute, P.O. Box 6226, Dar es Salaam, Tanzania
| | - Stephan Winter
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Plant Virus Department, Messeweg 11/12, 38104 Braunschweig, Germany
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Kozieł E, Bujarski JJ, Otulak K. Molecular Biology of Prune Dwarf Virus-A Lesser Known Member of the Bromoviridae but a Vital Component in the Dynamic Virus-Host Cell Interaction Network. Int J Mol Sci 2017; 18:E2733. [PMID: 29258199 PMCID: PMC5751334 DOI: 10.3390/ijms18122733] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 11/21/2017] [Accepted: 12/13/2017] [Indexed: 12/29/2022] Open
Abstract
Prune dwarf virus (PDV) is one of the members of Bromoviridae family, genus Ilarvirus. Host components that participate in the regulation of viral replication or cell-to-cell movement via plasmodesmata are still unknown. In contrast, viral infections caused by some other Bromoviridae members are well characterized. Bromoviridae can be distinguished based on localization of their replication process in infected cells, cell-to-cell movement mechanisms, and plant-specific response reactions. Depending upon the genus, "genome activation" and viral replication are linked to various membranous structures ranging from endoplasmic reticulum, to tonoplast. In the case of PDV, there is still no evidence of natural resistance sources in the host plants susceptible to virus infection. Apparently, PDV has a great ability to overcome the natural defense responses in a wide spectrum of plant hosts. The first manifestations of PDV infection are specific cell membrane alterations, and the formation of replicase complexes that support PDV RNA replication inside the spherules. During each stage of its life cycle, the virus uses cell components to replicate and to spread in whole plants, within the largely suppressed cellular immunity environment. This work presents the above stages of the PDV life cycle in the context of current knowledge about other Bromoviridae members.
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Affiliation(s)
- Edmund Kozieł
- Department of Botany, Faculty of Agriculture and Biology, Warsaw University of Life Sciences-SGGW, Nowoursynowska Street 159, 02-776 Warsaw, Poland.
| | - Józef J Bujarski
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland.
| | - Katarzyna Otulak
- Department of Botany, Faculty of Agriculture and Biology, Warsaw University of Life Sciences-SGGW, Nowoursynowska Street 159, 02-776 Warsaw, Poland.
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18
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Rakhshandehroo F, Rezaee S, Palukaitis P. Silencing the tobacco gene for RNA-dependent RNA polymerase 1 and infection by potato virus Y cause remodeling of cellular organelles. Virology 2017; 510:127-136. [PMID: 28719835 DOI: 10.1016/j.virol.2017.07.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/06/2017] [Accepted: 07/08/2017] [Indexed: 01/13/2023]
Abstract
RNA-dependent RNA polymerase 1 (RDR1) has been shown to be involved in DNA methylation, RNA silencing and regulating expression of other genes. RDR1 gene expression is stimulated by infection with potato virus Y° (PVY). Transgenic Nicotiana tabacum plants silenced for RDR1 gene expression showed morphological changes in mesophyll cells, associated with remodeling of the nuclei, chloroplasts and mitochondria. RDR1 silencing led to decreased nuclear size, increased heterochromatin content and aggregation, decreased numbers of chloroplasts, plus changes in shape, internal structures and integrity of chloroplasts and mitochondria. RDR1-silenced transgenic plants showed increased PVY accumulation and ultrastructural remodeling was intensified in both chloroplasts and mitochondria of PVY-infected, RDR1-silenced plants. By contrast, heterochromatin condensation was reduced by PVY infection, and in non-transgenic plants the nuclei were translucent and lacked morphology after PVY infection. Thus, RDR1 regulates gene expression leading to remodeling of chromosomes, and PVY infection counteracts these effects on chromosomal remodeling.
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Affiliation(s)
- Farshad Rakhshandehroo
- Department of Plant Pathology, College of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran 14515-775, Iran; James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Saeed Rezaee
- Department of Plant Pathology, College of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran 14515-775, Iran
| | - Peter Palukaitis
- James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK; Department of Horticultural Sciences, Seoul Women's University, Nowon-gu, Seoul 01797, Republic of Korea.
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Chaturvedi S, Seo JK, Rao A. Functionality of host proteins in Cucumber mosaic virus replication: GAPDH is obligatory to promote interaction between replication-associated proteins. Virology 2016; 494:47-55. [DOI: 10.1016/j.virol.2016.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 12/11/2022]
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20
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Chaturvedi S, Rao ALN. A shift in plant proteome profile for a Bromodomain containing RNA binding Protein (BRP1) in plants infected with Cucumber mosaic virus and its satellite RNA. J Proteomics 2016; 131:1-7. [PMID: 26463137 DOI: 10.1016/j.jprot.2015.09.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 09/03/2015] [Accepted: 09/30/2015] [Indexed: 12/18/2022]
Abstract
Host proteins are the integral part of a successful infection caused by a given RNA virus pathogenic to plants. Therefore, identification of crucial host proteins playing an important role in establishing the infection process is likely to help in devising approaches to curbing disease spread. Cucumber mosaic virus (Q-CMV) and its satellite RNA (QsatRNA) are important pathogens of many economically important crop plants worldwide. In a previous study, we demonstrated the biological significance of a Bromodomain containing RNA-binding Protein (BRP1) in the infection cycle of QsatRNA, making BRP1 an important host protein to study. To further shed a light on the mechanistic role of BRP1 in the replication of Q-CMV and QsatRNA, we analyzed the Nicotiana benthamiana host protein interactomes either for BRP1 alone or in the presence of Q-CMV or QsatRNA. Co-immunoprecipitation, followed by LC-MS/MS analysis of BRP1-FLAG on challenging with Q-CMV or QsatRNA has led us to observe a shift in the host protein interactome of BRP1. We discuss the significance of these results in relation to Q-CMV and its QsatRNA infection cycle. BIOLOGICAL SIGNIFICANCE Host proteins play an important role in replication and infection of eukaryotic cells by a wide-range of RNA viruses pathogenic to humans, animals and plants. Since a given eukaryotic cell typically contains ~30,000 different proteins, recent advances made in proteomics and bioinformatics approaches allowed the identification of host proteins critical for viral replication and pathogenesis. Although Cucumber mosaic virus (CMV) and its satRNA are well characterized at molecular level, information concerning the network of host factors involved in their replication and pathogenesis is still on its infancy. We have recently observed that a Bromodomain containing host protein (BRP1) is obligatory to transport satRNA to the nucleus. Consequently, it is imperative to apply proteomics and bioinformatics approaches in deciphering how host interactome network regulates the replication of CMV and its satRNA. In this study, first we established the importance of BRP1 in CMV replication. Then, application of co-immunoprecipitation in conjunction with LC-MS/MS allowed the identification of a wide range of host proteins that are associated with the replication of CMV and its satRNA. Interestingly, a shift in the plant proteome was observed when plants infected with CMV were challenged with its satRNA.
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Affiliation(s)
- Sonali Chaturvedi
- Department of Plant Pathology & Microbiology, University of California, Riverside, CA 92521, United States
| | - A L N Rao
- Department of Plant Pathology & Microbiology, University of California, Riverside, CA 92521, United States.
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Del Toro FJ, Aguilar E, Hernández-Walias FJ, Tenllado F, Chung BN, Canto T. High Temperature, High Ambient CO₂ Affect the Interactions between Three Positive-Sense RNA Viruses and a Compatible Host Differentially, but not Their Silencing Suppression Efficiencies. PLoS One 2015; 10:e0136062. [PMID: 26313753 PMCID: PMC4551900 DOI: 10.1371/journal.pone.0136062] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/29/2015] [Indexed: 12/14/2022] Open
Abstract
We compared infection of Nicotiana benthamiana plants by the positive-sense RNA viruses Cucumber mosaic virus (CMV), Potato virus Y (PVY), and by a Potato virus X (PVX) vector, the latter either unaltered or expressing the CMV 2b protein or the PVY HCPro suppressors of silencing, at 25°C vs. 30°C, or at standard (~401 parts per million, ppm) vs. elevated (970 ppm) CO2 levels. We also assessed the activities of their suppressors of silencing under those conditions. We found that at 30°C, accumulation of the CMV isolate and infection symptoms remained comparable to those at 25°C, whereas accumulation of the PVY isolate and those of the three PVX constructs decreased markedly, even when expressing the heterologous suppressors 2b or HCPro, and plants had either very attenuated or no symptoms. Under elevated CO2 plants grew larger, but contained less total protein/unit of leaf area. In contrast to temperature, infection symptoms remained unaltered for the five viruses at elevated CO2 levels, but viral titers in leaf disks as a proportion of the total protein content increased in all cases, markedly for CMV, and less so for PVY and the PVX constructs. Despite these differences, we found that neither high temperature nor elevated CO2 prevented efficient suppression of silencing by their viral suppressors in agropatch assays. Our results suggest that the strength of antiviral silencing at high temperature or CO2 levels, or those of the viral suppressors that counteract it, may not be the main determinants of the observed infection outcomes.
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Affiliation(s)
- Francisco J. Del Toro
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Emmanuel Aguilar
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Francisco J. Hernández-Walias
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Francisco Tenllado
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Bong-Nam Chung
- National Institute of Horticultural & Herbal Science, Agricultural Research Center for Climate Change, 281, Ayeon-ro, 690–150, Jeju, Jeju Island, Republic of Korea
| | - Tomas Canto
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
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22
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Un Huh S, Paek KH. Role of Arabidopsis Pumilio RNA binding protein 5 in virus infection. PLANT SIGNALING & BEHAVIOR 2013; 8:e23975. [PMID: 23511198 PMCID: PMC3906142 DOI: 10.4161/psb.23975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Regulation of gene expression is mediated by diverse RNA binding proteins which play important roles in development and defense processes. Pumilio/FBF (Puf) protein in mammals functions as a posttranscriptional/translational repressor by binding to the 3' UTR regions of its target mRNAs. Previous study reported that APUM5 provides protection against CMV infection by directly binding to CMV RNAs in Arabidopsis. CMV RNAs contain putative Pumilio-binding motifs and APUM5 bound to the 3' UTR and some of its internal motifs both in vitro and in vivo. APUM5 works as a negative regulator of the 3' UTR of CMV and it might regulate CMV replication. Our findings suggest that APUM5 acts as a defensive repressor in plants during CMV infection. However, functions of APUM5 and other APUM members are still not clear and more studies are needed to find out the interacting partners and target mRNAs in host plant.
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Ibrahim A, Hutchens HM, Berg RH, Loesch-Fries LS. Alfalfa mosaic virus replicase proteins, P1 and P2, localize to the tonoplast in the presence of virus RNA. Virology 2012; 433:449-61. [PMID: 22999257 DOI: 10.1016/j.virol.2012.08.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 08/01/2012] [Accepted: 08/07/2012] [Indexed: 12/25/2022]
Abstract
To identify the virus components important for assembly of the Alfalfa mosaic virus replicase complex, we used live cell imaging of Arabidopsis thaliana protoplasts that expressed various virus cDNAs encoding native and GFP-fusion proteins of P1 and P2 replicase proteins and full-length virus RNAs. Expression of P1-GFP alone resulted in fluorescent vesicle-like bodies in the cytoplasm that colocalized with FM4-64, an endocytic marker, and RFP-AtVSR2, RabF2a/Rha1-mCherry, and RabF2b/Ara7-mCherry, all of which localize to multivesicular bodies (MVBs), which are also called prevacuolar compartments, that mediate traffic to the lytic vacuole. GFP-P2 was driven from the cytosol to MVBs when expressed with P1 indicating that P1 recruited GFP-P2. P1-GFP localized on the tonoplast, which surrounds the vacuole, in the presence of infectious virus RNA, replication competent RNA2, or P2 and replication competent RNA1 or RNA3. This suggests that a functional replication complex containing P1, P2, and a full-length AMV RNA assembles on MVBs to traffic to the tonoplast.
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Affiliation(s)
- Amr Ibrahim
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
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Schoelz JE, Harries PA, Nelson RS. Intracellular transport of plant viruses: finding the door out of the cell. MOLECULAR PLANT 2011; 4:813-31. [PMID: 21896501 PMCID: PMC3183398 DOI: 10.1093/mp/ssr070] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 07/18/2011] [Indexed: 05/03/2023]
Abstract
Plant viruses are a class of plant pathogens that specialize in movement from cell to cell. As part of their arsenal for infection of plants, every virus encodes a movement protein (MP), a protein dedicated to enlarging the pore size of plasmodesmata (PD) and actively transporting the viral nucleic acid into the adjacent cell. As our knowledge of intercellular transport has increased, it has become apparent that viruses must also use an active mechanism to target the virus from their site of replication within the cell to the PD. Just as viruses are too large to fit through an unmodified plasmodesma, they are also too large to be freely diffused through the cytoplasm of the cell. Evidence has accumulated now for the involvement of other categories of viral proteins in intracellular movement in addition to the MP, including viral proteins originally associated with replication or gene expression. In this review, we will discuss the strategies that viruses use for intracellular movement from the replication site to the PD, in particular focusing on the role of host membranes for intracellular transport and the coordinated interactions between virus proteins within cells that are necessary for successful virus spread.
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Affiliation(s)
- James E. Schoelz
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Phillip A. Harries
- Department of Biology, Pittsburg State University, Pittsburg, KS 66762, USA
| | - Richard S. Nelson
- Plant Biology Division, The Samuel Roberts Noble Foundation, Inc., Ardmore, OK 73401, USA
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Huh SU, Kim MJ, Ham BK, Paek KH. A zinc finger protein Tsip1 controls Cucumber mosaic virus infection by interacting with the replication complex on vacuolar membranes of the tobacco plant. THE NEW PHYTOLOGIST 2011; 191:746-762. [PMID: 21477206 DOI: 10.1111/j.1469-8137.2011.03717.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
• In Cucumber mosaic virus (CMV) RNA replication, replicase-associated protein CMV 1a and RNA-dependent RNA polymerase protein CMV 2a are essential for formation of an active virus replicase complex on vacuolar membranes. • To identify plant host factors involved in CMV replication, a yeast two-hybrid system was used with CMV 1a protein as bait. One of the candidate genes encoded Tsi1-interacting protein 1 (Tsip1), a zinc (Zn) finger protein. Tsip1 strongly interacted with CMV 2a protein, too. • Formation of a Tsip1 complex involving CMV 1a or CMV 2a was confirmed in vitro and in planta. When 35S::Tsip1 tobacco (Nicotiana tabacum) plants were inoculated with CMV-Kor, disease symptom development was delayed and the accumulation of CMV RNAs and coat protein was decreased in both the infected local leaves and the uninfected upper leaves, compared with the wild type, whereas Tsip1-RNAi plants showed modestly but consistently increased CMV susceptibility. In a CMV replication assay, CMV RNA concentrations were reduced in the 35S::Tsip1 transgenic protoplasts compared with wild-type (WT) protoplasts. • These results indicate that Tsip1 might directly control CMV multiplication in tobacco plants by formation of a complex with CMV 1a and CMV 2a.
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Affiliation(s)
- Sung Un Huh
- School of Life Sciences and Biotechnology, Korea University, 1, 5-ga, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
| | - Min Jung Kim
- Examination Division of Food and Biological Resources, Korean Intellectual Property Office, Daejeon 302-701, Republic of Korea
| | - Byung-Kook Ham
- Section of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA
| | - Kyung-Hee Paek
- School of Life Sciences and Biotechnology, Korea University, 1, 5-ga, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
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26
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Choi SK, Yoon JY, Canto T, Palukaitis P. Replication of cucumber mosaic virus RNA 1 in cis requires functional helicase-like motifs of the 1a protein. Virus Res 2011; 158:271-6. [PMID: 21402113 DOI: 10.1016/j.virusres.2011.03.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 03/04/2011] [Accepted: 03/05/2011] [Indexed: 11/26/2022]
Abstract
The cucumber mosaic virus (CMV) encoded 1a protein contains an NTPase/helicase-like domain. To investigate whether various helicase motifs were required for efficient replication and to establish whether CMV RNA 1 could be replicated efficiently in cis, we constructed deletion mutations in helicase motifs I, III and VI and analyzed their effects on CMV RNA replication in tobacco. CMV replication was not detectable for any of the three helicase mutants, indicating that the helicase domain is crucial for efficient CMV replication. Both the wild-type and mutant 1a proteins could be detected at similar levels after transient expression in infiltrated tissues, indicating that the helicase-motif mutations did not affect the stability of the proteins. Co-inoculation tests with various mutant combinations did not result in complementation. In protoplasts derived from CMV RNA 1-transgenic tobacco, which supported replication of CMV RNAs 2 and 3, the RNA 1 helicase mutants were not replicated detectably in trans, but also did not interfere with the replication of the genomic RNAs, indicating that the conserved helicase motifs of the 1a protein are required in cis for the effective accumulation of RNA 1.
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Affiliation(s)
- Seung Kook Choi
- Institute of Natural Science, Myong-Ji University, Yong-In 449-728, South Korea
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27
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Harries PA, Schoelz JE, Nelson RS. Intracellular transport of viruses and their components: utilizing the cytoskeleton and membrane highways. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2010; 23:1381-93. [PMID: 20653412 DOI: 10.1094/mpmi-05-10-0121] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Plant viruses are obligate organisms that require host components for movement within and between cells. A mechanistic understanding of virus movement will allow the identification of new methods to control virus systemic spread and serve as a model system for understanding host macromolecule intra- and intercellular transport. Recent studies have moved beyond the identification of virus proteins involved in virus movement and their effect on plasmodesmal size exclusion limits to the analysis of their interactions with host components to allow movement within and between cells. It is clear that individual virus proteins and replication complexes associate with and, in some cases, traffic along the host cytoskeleton and membranes. Here, we review these recent findings, highlighting the diverse associations observed between these components and their trafficking capacity. Plant viruses operate individually, sometimes within virus species, to utilize unique interactions between their proteins or complexes and individual host cytoskeletal or membrane elements over time or space for their movement. However, there is not sufficient information for any plant virus to create a complete model of its intracellular movement; thus, more research is needed to achieve that goal.
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Affiliation(s)
- Phillip A Harries
- Department of Biology, Pittsburg State University, Pittsburg, KS 66762, USA
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28
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Mascia T, Cillo F, Fanelli V, Finetti-Sialer MM, De Stradis A, Palukaitis P, Gallitelli D. Characterization of the interactions between Cucumber mosaic virus and Potato virus Y in mixed infections in tomato. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2010; 23:1514-24. [PMID: 20923355 DOI: 10.1094/mpmi-03-10-0064] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Mixed infection with the SON41 strain of Potato virus Y (PVY-SON41) in tomato increased accumulation of RNAs of strains Fny and LS of Cucumber mosaic virus (CMV-Fny and CMV-LS, respectively) and enhanced disease symptoms. By contrast, replication of PVY-SON41 was downregulated by CMV-Fny and this was due to the CMV-Fny 2b protein. The CMV-FnyΔ2b mutant was unable to systemically invade the tomato plant because its movement was blocked at the bundle sheath of the phloem. The function needed for invading the phloem was complemented by PVY-SON41 in plants grown at 22°C whereas this complementation was not necessary in plants grown at 15°C. Mutations in the 2b protein coding sequence of CMV-Fny as well as inhibition of translation of the 2a/2b overlapping region of the 2a protein lessened both the accumulation of viral RNAs and the severity of symptoms. Both of these functions were complemented by PVY-SON41. Infection of CMV-Fny supporting replication of the Tfn-satellite RNA reduced the accumulation of CMV RNA and suppressed symptom expression also in plants mixed-infected with PVY-SON41. The interaction between CMV and PVY-SON41 in tomato exhibited different features from that documented in other hosts. The results of this work are relevant from an ecological and epidemiological perspective due to the frequency of natural mixed infection of CMV and PVY in tomato.
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Affiliation(s)
- Tiziana Mascia
- Dipartimento di Protezione delle Piante e Microbiologia Applicata, Università degli Studi di Bari, Via Amendola 165/A, 70126 Bari, Italy.
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29
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Seo JK, Kwon SJ, Choi HS, Kim KH. Evidence for alternate states of Cucumber mosaic virus replicase assembly in positive- and negative-strand RNA synthesis. Virology 2009; 383:248-60. [PMID: 19022467 DOI: 10.1016/j.virol.2008.10.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 08/30/2008] [Accepted: 10/21/2008] [Indexed: 01/22/2023]
Abstract
Cucumber mosaic virus (CMV) encodes two viral replication proteins, 1a and 2a. Accumulating evidence implies that different aspects of 1a-2a interaction in replication complex assembly are involved in the regulation of virus replication. To further investigate CMV replicase assembly and to dissect the involvement of replicase activities in negative- and positive-strand synthesis, we transiently expressed CMV RNAs and/or proteins in Nicotiana benthamiana leaves using a DNA or RNA-mediated expression system. Surprisingly, we found that, even in the absence of 1a, 2a is capable of synthesizing positive-strand RNAs, while 1a and 2a are both required for negative-strand synthesis. We also report evidence that 1a capping activities function independently of 2a. Moreover, using 1a mutants, we show that capping activities of 1a are crucial for viral translation but not for RNA transcription. These results support the concept that two or more alternate states of replicase assembly are involved in CMV replication.
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Affiliation(s)
- Jang-Kyun Seo
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
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30
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Abstract
A variety of techniques have been used to examine plant viral genomes, the functions of virus-encoded proteins, plant responses induced by virus infection and plant-virus interactions. This overview considers these technologies and how they have been used to identify novel viral and plant proteins or genes involved in disease and resistance responses, as well as defense signaling. These approaches include analysis of spatial and temporal responses by plants to infection, and techniques that allow the expression of viral genes transiently or transgenically in planta, the expression of plant and foreign genes from virus vectors, the silencing of plants genes, imaging of live, infected cells, and the detection of interactions between viral proteins and plant gene products, both in planta and in various in vitro or in vivo systems. These methods and some of the discoveries made using these approaches are discussed.
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Affiliation(s)
- Peter Palukaitis
- Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, UK
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31
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Shi BJ, Symons RH, Palukaitis P. The cucumovirus 2b gene drives selection of inter-viral recombinants affecting the crossover site, the acceptor RNA and the rate of selection. Nucleic Acids Res 2007; 36:1057-71. [PMID: 18086712 PMCID: PMC2275080 DOI: 10.1093/nar/gkm1036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RNA–RNA recombination is an important pathway in virus evolution and has been described for many viruses. However, the factors driving recombination or promoting the selection of recombinants are still unclear. Here, we show that the small movement protein (2b) was able to promote selection of RNA 1/2–RNA 3 recombinants within a chimeric virus having RNAs 1 and 2 from cucumber mosaic virus, and RNA 3 from the related tomato aspermy virus, along with heterologous 2b genes. The source of the 2b also determined the selection of the acceptor RNA and the crossover site, as well as affecting the rate of selection of the recombinant RNAs. The nature of the RNA 3 also influenced the selection of the recombinant RNAs. A 163-nt tandem repeat in RNA 3 significantly affected the rate of selection of the recombinant RNA, while a single nucleotide within the repeat affected the crossover site. The recombination occurred in a non-random manner, involved no intermediates and probably was generated via a copy-choice mechanism during (+) strand RNA synthesis.
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Affiliation(s)
- Bu-Jun Shi
- Australian Centre for Plant Functional Genomics, University of Adelaide, School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA 5064, Australia.
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32
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Wege C, Siegmund D. Synergism of a DNA and an RNA virus: enhanced tissue infiltration of the begomovirus Abutilon mosaic virus (AbMV) mediated by Cucumber mosaic virus (CMV). Virology 2007; 357:10-28. [PMID: 16959287 DOI: 10.1016/j.virol.2006.07.043] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2005] [Revised: 01/19/2006] [Accepted: 07/26/2006] [Indexed: 11/29/2022]
Abstract
Replication of the begomovirus Abutilon mosaic virus (AbMV) is restricted to phloem nuclei, generating moderate levels of virus DNA. Co-infection with Cucumber mosaic virus (CMV) evidently increased AbMV titers in Nicotiana benthamiana, tobacco, and tomato, resulting in synergistic symptom enhancement. In situ hybridization revealed that in double-infected leaves an increased number of nuclei contained elevated amounts of AbMV. Additionally, the begomoviral phloem-limitation was broken. Whereas CMV 3a movement protein-expressing tobacco plants did not exert any similar influence, the presence of CMV 2b silencing suppressor protein lead to enhanced AbMV titers and numbers of infected vascular cells. The findings prove that AbMV can replicate in nonvascular cells and represent the first report on a true synergism of an RNA/ssDNA virus combination in plants, in which CMV 2b protein plays a role. They indicate considerable consequences of mixed infections between begomo- and cucumoviruses on virus epidemiology and agriculture.
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Affiliation(s)
- Christina Wege
- Department of Plant Molecular Biology and Plant Virology, Universität Stuttgart, Institute of Biology, Pfaffenwaldring 57, D-70569 Stuttgart, Germany.
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33
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Ding XS, Schneider WL, Chaluvadi SR, Mian MAR, Nelson RS. Characterization of a Brome mosaic virus strain and its use as a vector for gene silencing in monocotyledonous hosts. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2006; 19:1229-39. [PMID: 17073305 DOI: 10.1094/mpmi-19-1229] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Virus-induced gene silencing (VIGS) is used to analyze gene function in dicotyledonous plants but less so in monocotyledonous plants (particularly rice and corn), partially due to the limited number of virus expression vectors available. Here, we report the cloning and modification for VIGS of a virus from Festuca arundinacea Schreb. (tall fescue) that caused systemic mosaic symptoms on barley, rice, and a specific cultivar of maize (Va35) under greenhouse conditions. Through sequencing, the virus was determined to be a strain of Brome mosaic virus (BMV). The virus was named F-BMV (F for Festuca), and genetic determinants that controlled the systemic infection of rice were mapped to RNAs 1 and 2 of the tripartite genome. cDNA from RNA 3 of the Russian strain of BMV (R-BMV) was modified to accept inserts from foreign genes. Coinoculation of RNAs 1 and 2 from F-BMV and RNA 3 from R-BMV expressing a portion of a plant gene to leaves of barley, rice, and maize plants resulted in visual silencing-like phenotypes. The visual phenotypes were correlated with decreased target host transcript levels in the corresponding leaves. The VIGS visual phenotype varied from maintained during silencing of actin 1 transcript expression to transient with incomplete penetration through affected tissue during silencing of phytoene desaturase expression. F-BMV RNA 3 was modified to allow greater accumulation of virus while minimizing virus pathogenicity. The modified vector C-BMV(A/G) (C for chimeric) was shown to be useful for VIGS. These BMV vectors will be useful for analysis of gene function in rice and maize for which no VIGS system is reported.
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Affiliation(s)
- Xin Shun Ding
- Samuel Roberts Noble Foundation, Inc., 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
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34
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Kim MJ, Kim HR, Paek KH. Arabidopsis tonoplast proteins TIP1 and TIP2 interact with the cucumber mosaic virus 1a replication protein. J Gen Virol 2006; 87:3425-3431. [PMID: 17030879 DOI: 10.1099/vir.0.82252-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The cucumber mosaic virus (CMV) replication complex has previously been shown to associate with cellular membranes. However, it remains unknown whether any host factors participate in this process. In this study, five groups of Arabidopsis tonoplast intrinsic protein (TIP) genes were isolated and the proteins they encoded were evaluated with regard to their interactions with CMV proteins. TIP1 and TIP2 were found to interact with the CMV 1a protein in the Sos recruitment system, whereas no interactions with the other three TIP subgroups were observed in this assay. The interaction of CMV 1a with the TIP1 and TIP2 proteins was confirmed via co-immunoprecipitation assays. Additionally, CMV 1a co-localized with TIP1 and TIP2 in transfected Arabidopsis protoplasts. The findings of this study suggest that members of two TIP subfamilies might affect CMV replication via interaction with CMV 1a in the tonoplasts.
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Affiliation(s)
- Min Jung Kim
- School of Life Sciences and Biotechnology, Korea University, 1 5-ga Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
| | - Hwa Ran Kim
- School of Life Sciences and Biotechnology, Korea University, 1 5-ga Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
| | - Kyung-Hee Paek
- School of Life Sciences and Biotechnology, Korea University, 1 5-ga Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
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35
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36
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Kim MJ, Ham BK, Paek KH. Novel protein kinase interacts with the Cucumber mosaic virus 1a methyltransferase domain. Biochem Biophys Res Commun 2005; 340:228-35. [PMID: 16360640 DOI: 10.1016/j.bbrc.2005.11.178] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2005] [Accepted: 11/30/2005] [Indexed: 11/23/2022]
Abstract
The Cucumber mosaic virus (CMV)-encoded 1a protein has been implicated to play a role in replication of the viral genome along with 2a and one or more host factors. To identify the host cell factors interacting with CMV 1a, we used the yeast two-hybrid system using tobacco cDNA library. One of the cDNA clones encoded a protein homologous to the Arabidopsis putative protein kinase and was designated as Tcoi2 (Tobacco CMV 1a interacting protein 2). Tcoi2 specifically interacted with methyltransferase (MT) domain of CMV 1a protein in yeast cell. In vitro analyses using recombinant proteins showed that Tcoi2 also specifically interacted with CMV 1a MT domain. Tcoi2 did not have autophosphorylation activity but phosphorylated CMV 1a MT domain. Analysis of the subcellular localization of the Tcoi2 fused to GFP demonstrated that it is targeted to the endoplasmic reticulum. These results suggest Tcoi2 as a novel host factor that is capable of interacting and phosphorylating MT domain of CMV 1a protein.
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Affiliation(s)
- Min Jung Kim
- School of Life Sciences and Biotechnology, Korea University, 1, 5-ga, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
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37
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Sanfaçon H. Replication of positive-strand RNA viruses in plants: contact points between plant and virus components. ACTA ACUST UNITED AC 2005. [DOI: 10.1139/b05-121] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Positive-strand RNA viruses constitute the largest group of plant viruses and have an important impact on world agriculture. These viruses have small genomes that encode a limited number of proteins and depend on their hosts to complete the various steps of their replication cycle. In this review, the contact points between positive-strand RNA plant viruses and their hosts, which are necessary for the translation and replication of the viral genomes, are discussed. Special emphasis is placed on the description of viral replication complexes that are associated with specific membranous compartments derived from plant intracellular membranes and contain viral RNAs and proteins as well as a variety of host proteins. These complexes are assembled via an intricate network of protein–protein, protein–membrane, and protein–RNA interactions. The role of host factors in regulating the assembly, stability, and activity of viral replication complexes are also discussed.
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Affiliation(s)
- Hélène Sanfaçon
- Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, 4200 Highway 97, Summerland, BC V0H 1Z0, Canada (e-mail: )
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38
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Ding B, Itaya A, Zhong X. Viroid trafficking: a small RNA makes a big move. CURRENT OPINION IN PLANT BIOLOGY 2005; 8:606-12. [PMID: 16181802 DOI: 10.1016/j.pbi.2005.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Accepted: 09/09/2005] [Indexed: 05/04/2023]
Abstract
RNA trafficking has broad implications in the systemic spread of infectious agents, plant defense, and the systemic regulation of gene expression. The mechanisms that regulate trafficking remain poorly understood. The non-coding, infectious viroid RNAs are emerging as highly tractable model systems for the investigation of the basic mechanisms of RNA trafficking. Recent studies on viroids have led to new insights into the direct role of RNAs in intracellular and systemic trafficking, and to the identification of cellular proteins that might play a role in RNA trafficking. Here, we discuss these areas of progress, emphasizing on the unifying principles that control the trafficking of viroid, viral and endogenous RNAs.
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Affiliation(s)
- Biao Ding
- Department of Plant Cellular and Molecular Biology and Plant Biotechnology Center, 207 Rightmire Hall, The Ohio State University, 1060 Carmack Road, Columbus, Ohio 43210, USA.
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39
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Hwang MS, Kim SH, Lee JH, Bae JM, Paek KH, Park YI. Evidence for interaction between the 2a polymerase protein and the 3a movement protein of Cucumber mosaic virus. J Gen Virol 2005; 86:3171-3177. [PMID: 16227241 DOI: 10.1099/vir.0.81139-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The genome of Cucumber mosaic virus consists of three single-stranded RNA molecules, RNAs 1, 2 and 3. RNAs 1 and 2 encode the 1a and 2a proteins, respectively, which are necessary for replication of the viral genome and have been implicated in movement of the viral RNAs in plants. The 3a movement protein (MP), encoded by RNA 3, is essential for transferring the RNA genomes from infected cells to adjacent cells across the plasmodesmata. Far-Western analysis demonstrated that bacterially expressed 2a polymerase protein directly interacted with the MP. Interaction was confirmed in a yeast two-hybrid assay, and co-immunoprecipitation analysis showed that the MP interacted only with the 2a polymerase protein. A yeast three-hybrid assay showed that the 1a–2a protein interaction relevant for replicase complex formation was not affected by the MP. Although the MP has no affinity for the 1a protein, it interacted indirectly with the 1a protein via the 2a polymerase protein. These results suggest that the replicase complex may be involved in movement through its interaction with the MP.
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Affiliation(s)
- Min Sook Hwang
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
| | - Sang Hyon Kim
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
| | - Jeong Hyun Lee
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
| | - Jung Myung Bae
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
| | - Kyung Hee Paek
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
| | - Young In Park
- School of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-701, Korea
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40
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Divéki Z, Salánki K, Balázs E. The necrotic pathotype of the cucumber mosaic virus (CMV) ns strain is solely determined by amino acid 461 of the 1a protein. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2004; 17:837-45. [PMID: 15305604 DOI: 10.1094/mpmi.2004.17.8.837] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The unique Ns isolate of Cucumber mosaic virus (CMV) induces necrotic lesions on several Nicotiana spp. in contrast to other strains that cause systemic mosaic on these plants. By using biologically active RNA transcripts from cDNAs of Ns-CMV and a reference subgroup I strain Rs-CMV, we confined the genetic determinant solely responsible for necrosis induction to amino acid 461 of the la protein translated from genomic RNA1. An Arg to Cys change at this position (R461C) rendered Rs-CMV necrotic, whereas the reciprocal C461R mutation reverted the necrotic phenotype of Ns-CMV. Necrotic (Ns-CMV, R461C) and non-necrotic (Rs-CMV and C461R) viruses accumulated to similar levels in Nicotiana clevelandii protoplasts. Deletion of the residue at position 461 abolished replicase activity of the Ns-CMV 1a protein. The R461C mutation also was introduced into the 1a protein of Trk7-CMV, a subgroup II isolate. Symptoms induced by the Trk7/R461C mutant were identical to those caused by wild-type Trk7-CMV, even when the mutant Trk7 RNA1 was co-inoculated with RNA2 and 3 of the necrotic Ns strain.
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Affiliation(s)
- Zoltán Divéki
- Agricultural Biotechnology Center, Environmental Biosafety Research Institute, P.O. Box 411. Gödöllö, H-2101 Hungary
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41
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Lin HX, Rubio L, Smythe AB, Falk BW. Molecular population genetics of Cucumber mosaic virus in California: evidence for founder effects and reassortment. J Virol 2004; 78:6666-75. [PMID: 15163757 PMCID: PMC416521 DOI: 10.1128/jvi.78.12.6666-6675.2004] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2003] [Accepted: 02/18/2004] [Indexed: 11/20/2022] Open
Abstract
The structure and genetic diversity of a California Cucumber mosaic virus (CMV) population was assessed by single-strand conformation polymorphism and nucleotide sequence analyses of genomic regions 2b, CP, MP, and the 3' nontranslated region of RNA3. The California CMV population exhibited low genetic diversity and was composed of one to three predominant haplotypes and a large number of minor haplotypes for specific genomic regions. Extremely low diversity and close evolutionary relationships among isolates in a subpopulation suggested that founder effects might play a role in shaping the genetic structure. Phylogenetic analysis indicated a naturally occurring reassortant between subgroup IA and IB isolates and potential reassortants between subgroup IA isolates, suggesting that genetic exchange by reassortment contributed to the evolution of the California CMV population. Analysis of various population genetics parameters and distribution of synonymous and nonsynonymous mutations revealed that different coding regions and even different parts of coding regions were under different evolutionary constraints, including a short region of the 2b gene for which evidence suggests possible positive selection.
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Affiliation(s)
- Han-Xin Lin
- Department of Plant Pathology, University of California-Davis, 1 Shields Avenue, Davis, CA 95616, USA
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42
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Abstract
Research on the molecular biology of cucumoviruses and their plant-virus interactions has been very extensive in the last decade. Cucumovirus genome structures have been analyzed, giving new insights into their genetic variability, evolution, and taxonomy. A new viral gene has been discovered, and its role in promoting virus infection has been delineated. The localization and various functions of each viral-encoded gene product have been established. The particle structures of Cucumber mosaic virus (CMV) and Tomato aspermy virus have been determined. Pathogenicity domains have been mapped, and barriers to virus infection have been localized. The movement pathways of the viruses in some hosts have been discerned, and viral mutants affecting the movement processes have been identified. Host responses to viral infection have been characterized, both temporally and spatially. Progress has been made in determining the mechanisms of replication, gene expression, and transmission of CMV. The pathogenicity determinants of various satellite RNAs have been characterized, and the importance of secondary structure in satellite RNA-mediated interactions has been recognized. Novel plant genes specifying resistance to infection by CMV have been identified. In some cases, these genes have been mapped, and one resistance gene to CMV has been isolated and characterized. Pathogen-derived resistance has been demonstrated against CMV using various segments of the CMV genome, and the mechanisms of some of these forms of resistances have been analyzed. Finally, the nature of synergistic interactions between CMV and other viruses has been characterized. This review highlights these various achievements in the context of the previous work on the biology of cucumoviruses and their interactions with plants.
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Affiliation(s)
- Peter Palukaitis
- Gene Expression Programme, Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, United Kingdom
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43
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Qi Y, Ding B. Differential subnuclear localization of RNA strands of opposite polarity derived from an autonomously replicating viroid. THE PLANT CELL 2003; 15:2566-77. [PMID: 14555700 PMCID: PMC280561 DOI: 10.1105/tpc.016576] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2003] [Accepted: 09/13/2003] [Indexed: 05/20/2023]
Abstract
The wide variety of RNAs produced in the nucleus must be localized correctly to perform their functions. However, the mechanism of this localization is poorly understood. We report here the differential subnuclear localization of RNA strands of opposite polarity derived from the replicating Potato spindle tuber viroid (PSTVd). During replication, (+)- and (-)-strand viroid RNAs are produced. We found that in infected cultured cells and plants, the (-)-strand RNA was localized in the nucleoplasm, whereas the (+)-strand RNA was localized in the nucleolus as well as in the nucleoplasm with distinct spatial patterns. Furthermore, the presence of the (+)-PSTVd in the nucleolus caused the redistribution of a small nucleolar RNA. Our results support a model in which (1) the synthesis of the (-)- and (+)-strands of PSTVd RNAs occurs in the nucleoplasm, (2) the (-)-strand RNA is anchored in the nucleoplasm, and (3) the (+)-strand RNA is transported selectively into the nucleolus. Our results imply that the eukaryotic cell has a machinery that recognizes and localizes the opposite strands of an RNA, which may have broad ramifications in the RNA regulation of gene expression and the infection cycle of pathogenic RNAs and in the development of RNA-based methods to control gene expression as well as pathogen infection.
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Affiliation(s)
- Yijun Qi
- Department of Plant Biology and Plant Biotechnology Center, Ohio State University, Columbus, Ohio 43210, USA
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