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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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2
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Sett S, Prasad A, Prasad M. Resistance genes on the verge of plant-virus interaction. TRENDS IN PLANT SCIENCE 2022; 27:1242-1252. [PMID: 35902346 DOI: 10.1016/j.tplants.2022.07.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 06/06/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
Viruses are acellular pathogens that cause severe infections in plants, resulting in worldwide crop losses every year. The lack of chemical agents to control viral diseases exacerbates the situation. Thus, to devise proper management strategies, it is important that the defense mechanisms of plants against viruses are understood. Resistance (R) genes regulate plant defense against invading pathogens by eliciting a hypersensitive response (HR). Compatible interaction between plant R gene and viral avirulence (Avr) protein activates the necrotic cell death response at the site of infection, resulting in the cessation of disease. Here, we review different aspects of R gene-mediated dominant resistance against plant viruses in dicotyledonous plants and possible ways for developing crops with better disease resistance.
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Affiliation(s)
- Susmita Sett
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Ashish Prasad
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Manoj Prasad
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India; Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India.
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3
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Jhu MY, Farhi M, Wang L, Philbrook RN, Belcher MS, Nakayama H, Zumstein KS, Rowland SD, Ron M, Shih PM, Sinha NR. Heinz-resistant tomato cultivars exhibit a lignin-based resistance to field dodder (Cuscuta campestris) parasitism. PLANT PHYSIOLOGY 2022; 189:129-151. [PMID: 35099559 PMCID: PMC9070836 DOI: 10.1093/plphys/kiac024] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/20/2021] [Indexed: 05/27/2023]
Abstract
Cuscuta species (dodders) are agriculturally destructive, parasitic angiosperms. These parasitic plants use haustoria as physiological bridges to extract nutrients and water from hosts. Cuscuta campestris has a broad host range and wide geographical distribution. While some wild tomato relatives are resistant, cultivated tomatoes are generally susceptible to C. campestris infestations. However, some specific Heinz tomato (Solanum lycopersicum) hybrid cultivars exhibit resistance to dodders in the field, but their defense mechanism was previously unknown. Here, we discovered that the stem cortex in these resistant lines responds with local lignification upon C. campestris attachment, preventing parasite entry into the host. Lignin Induction Factor 1 (LIF1, an AP2-like transcription factor), SlMYB55, and Cuscuta R-gene for Lignin-based Resistance 1, a CC-NBS-LRR (CuRLR1) are identified as factors that confer host resistance by regulating lignification. SlWRKY16 is upregulated upon C. campestris infestation and potentially negatively regulates LIF1 function. Intriguingly, CuRLR1 may play a role in signaling or function as an intracellular receptor for receiving Cuscuta signals or effectors, thereby regulating lignification-based resistance. In summary, these four regulators control the lignin-based resistance response in specific Heinz tomato cultivars, preventing C. campestris from parasitizing resistant tomatoes. This discovery provides a foundation for investigating multilayer resistance against Cuscuta species and has potential for application in other essential crops attacked by parasitic plants.
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Affiliation(s)
| | | | - Li Wang
- Department of Plant Biology, University of California, Davis, CA 95616, USA
- College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, China
| | - Richard N Philbrook
- Department of Plant Biology, University of California, Davis, CA 95616, USA
- Dark Heart Nursery, 630 Pena Dr, Davis, CA 95616, USA
| | - Michael S Belcher
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Hokuto Nakayama
- Department of Plant Biology, University of California, Davis, CA 95616, USA
- Graduate School of Science, Department of Biological Sciences, University of Tokyo, Hongo Bunkyo-ku, Tokyo, 113-0033, Japan
| | | | - Sarah D Rowland
- Department of Plant Biology, University of California, Davis, CA 95616, USA
| | - Mily Ron
- Department of Plant Biology, University of California, Davis, CA 95616, USA
| | - Patrick M Shih
- Department of Plant Biology, University of California, Davis, CA 95616, USA
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Genome Center, University of California, Davis, CA 95616, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Hak H, Spiegelman Z. The Tomato Brown Rugose Fruit Virus Movement Protein Overcomes Tm-22 Resistance in Tomato While Attenuating Viral Transport. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:1024-1032. [PMID: 33970669 DOI: 10.1094/mpmi-01-21-0023-r] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Tomato brown rugose fruit virus is a new virus species in the Tobamovirus genus, causing substantial damage to tomato crops. Reports of recent tomato brown rugose fruit virus (ToBRFV) outbreaks from around the world indicate an emerging global epidemic. ToBRFV overcomes all tobamovirus resistances in tomato, including the durable Tm-22 resistance gene, which had been effective against multiple tobamoviruses. Here, we show that the ToBRFV movement protein (MPToBRFV) enables the virus to evade Tm-22 resistance. Transient expression of MPToBRFV failed to activate the Tm-22 resistance response. Replacement of the original MP sequence of tomato mosaic virus (ToMV) with MPToBRFV enabled this recombinant virus to infect Tm-22-resistant plants. Using hybrid protein analysis, we show that the elements required to evade Tm-22 are located between MPToBRFV amino acids 1 and 216 and not the C terminus, as previously assumed. Analysis of ToBRFV systemic infection in tomato revealed that ToBRFV spreads more slowly compared with ToMV. Interestingly, replacement of tobacco mosaic virus (TMV) and ToMV MPs with MPToBRFV caused an attenuation of systemic infection of both viruses. Cell-to-cell movement analysis showed that MPToBRFV moves less effectively compared with the TMV MP (MPTMV). These findings suggest that overcoming Tm-22 is associated with attenuated MP function. This may explain the high durability of Tm-22 resistance, which had remained unbroken for over 60 years.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Hagit Hak
- Department of Plant Pathology and Weed Research, Agricultural Research Organization-The Volcani Center, 68 HaMaccabim Road, P.O.B 15159, Rishon LeZion 7505101, Israel
| | - Ziv Spiegelman
- Department of Plant Pathology and Weed Research, Agricultural Research Organization-The Volcani Center, 68 HaMaccabim Road, P.O.B 15159, Rishon LeZion 7505101, Israel
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Richard MMS, Knip M, Schachtschabel J, Beijaert MS, Takken FLW. Perturbation of nuclear-cytosolic shuttling of Rx1 compromises extreme resistance and translational arrest of potato virus X transcripts. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:468-479. [PMID: 33524169 PMCID: PMC8252585 DOI: 10.1111/tpj.15179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 01/24/2021] [Accepted: 01/26/2021] [Indexed: 06/01/2023]
Abstract
Many plant intracellular immune receptors mount a hypersensitive response (HR) upon pathogen perception. The concomitant localized cell death is proposed to trap pathogens, such as viruses, inside infected cells, thereby preventing their spread. Notably, extreme resistance (ER) conferred by the potato immune receptor Rx1 to potato virus X (PVX) does not involve the death of infected cells. It is unknown what defines ER and how it differs from HR-based resistance. Interestingly, Rx1 can trigger an HR, but only upon artificial (over)expression of PVX or its avirulence coat protein (CP). Rx1 has a nucleocytoplasmic distribution and both pools are required for HR upon transient expression of a PVX-GFP amplicon. It is unknown whether mislocalized Rx1 variants can induce ER upon natural PVX infection. Here, we generated transgenic Nicotiana benthamiana producing nuclear- or cytosol-restricted Rx1 variants. We found that these variants can still mount an HR. However, nuclear- or cytosol-restricted Rx1 variants can no longer trigger ER or restricts viral infection. Interestingly, unlike the mislocalized Rx1 variants, wild-type Rx1 was found to compromise CP protein accumulation. We show that the lack of CP accumulation does not result from its degradation but is likely to be linked with translational arrest of its mRNA. Together, our findings suggest that translational arrest of viral genes is a major component of ER and, unlike the HR, is required for resistance to PVX.
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Affiliation(s)
- Manon M. S. Richard
- Molecular Plant PathologySwammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamthe Netherlands
| | - Marijn Knip
- Molecular Plant PathologySwammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamthe Netherlands
| | - Joëlle Schachtschabel
- Molecular Plant PathologySwammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamthe Netherlands
| | - Machiel S. Beijaert
- Molecular Plant PathologySwammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamthe Netherlands
| | - Frank L. W. Takken
- Molecular Plant PathologySwammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamthe Netherlands
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6
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Künstler A, Király L, Kátay G, Enyedi AJ, Gullner G. Glutathione Can Compensate for Salicylic Acid Deficiency in Tobacco to Maintain Resistance to Tobacco Mosaic Virus. FRONTIERS IN PLANT SCIENCE 2019; 10:1115. [PMID: 31608082 PMCID: PMC6769422 DOI: 10.3389/fpls.2019.01115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 08/14/2019] [Indexed: 05/12/2023]
Abstract
Earlier studies showed that the artificial elevation of endogenous glutathione (GSH) contents can markedly increase the resistance of plants against different viruses. On the other hand, salicylic acid (SA)-deficient NahG plants display enhanced susceptibility to viral infections. In the present study, the biochemical mechanisms underlying GSH-induced resistance were investigated in various tobacco biotypes displaying markedly different GSH and SA levels. The endogenous GSH levels of Nicotiana tabacum cv. Xanthi NN and N. tabacum cv. Xanthi NN NahG tobacco leaves were increased by infiltration of exogenous GSH or its synthetic precursor R-2-oxo-4-thiazolidine-carboxylic acid (OTC). Alternatively, we also used tobacco lines containing high GSH levels due to transgenes encoding critical enzymes for cysteine and GSH biosynthesis. We crossed Xanthi NN and NahG tobaccos with the GSH overproducer transgenic tobacco lines in order to obtain F1 progenies with increased levels of GSH and decreased levels of SA. We demonstrated that in SA-deficient NahG tobacco the elevation of in planta GSH and GSSG levels either by exogenous GSH or by crossing with glutathione overproducing plants confers enhanced resistance to Tobacco mosaic virus (TMV) manifested as both reduced symptoms (i.e. suppression of hypersensitive-type localized necrosis) and lower virus titers. The beneficial effects of elevated GSH on TMV resistance was markedly stronger in NahG than in Xanthi NN leaves. Infiltration of exogenous GSH and OTC or crossing with GSH overproducer tobacco lines resulted in a substantial rise of bound SA and to a lesser extent of free SA levels in tobacco, especially following TMV infection. Significant increases in expression of pathogenesis related (NtPR-1a, and NtPRB-1b), and glutathione S-transferase (NtGSTtau, and NtGSTphi) genes were evident in TMV-inoculated leaves in later stages of pathogenesis. However, the highest levels of defense gene expression were associated with SA-deficiency, rather than enhanced TMV resistance. In summary, elevated levels of glutathione in TMV-infected tobacco can compensate for SA deficiency to maintain virus resistance. Our results suggest that glutathione-induced redox changes are important components of antiviral signaling in tobacco.
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Affiliation(s)
- András Künstler
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Lóránt Király
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - György Kátay
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Alexander J Enyedi
- Office of Academic Affairs, Humboldt State University, Arcata, CA, United States
| | - Gábor Gullner
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
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Meier N, Hatch C, Nagalakshmi U, Dinesh‐Kumar SP. Perspectives on intracellular perception of plant viruses. MOLECULAR PLANT PATHOLOGY 2019; 20:1185-1190. [PMID: 31282091 PMCID: PMC6715608 DOI: 10.1111/mpp.12839] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The intracellular nucleotide-binding domain leucine-rich repeat (NLR) class of immune receptors plays an important role in plant viral defence. Plant NLRs recognize viruses through direct or indirect association of viral proteins, triggering a downstream defence response to prevent viral proliferation and movement within the plant. This review focuses on current knowledge of intracellular perception of viral pathogens, activation of NLRs and the downstream signalling components involved in plant viral defence.
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Affiliation(s)
- Nathan Meier
- Department of Plant Biology and The Genome Center, College of Biological SciencesUniversity of CaliforniaDavisCA95616USA
| | - Cameron Hatch
- Department of Plant Biology and The Genome Center, College of Biological SciencesUniversity of CaliforniaDavisCA95616USA
| | - Ugrappa Nagalakshmi
- Department of Plant Biology and The Genome Center, College of Biological SciencesUniversity of CaliforniaDavisCA95616USA
| | - Savithramma P. Dinesh‐Kumar
- Department of Plant Biology and The Genome Center, College of Biological SciencesUniversity of CaliforniaDavisCA95616USA
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8
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Nagy PD. Exploitation of a surrogate host, Saccharomyces cerevisiae, to identify cellular targets and develop novel antiviral approaches. Curr Opin Virol 2017; 26:132-140. [PMID: 28843111 DOI: 10.1016/j.coviro.2017.07.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 07/30/2017] [Indexed: 12/16/2022]
Abstract
Plant RNA viruses are widespread pathogens that need to interact intricately with their hosts to co-opt numerous cellular factors to facilitate their replication. Currently, there are only a limited number of plant resistance genes against a limited number of viruses. To develop novel antiviral approaches, the interaction network between the given virus and the host cell could be targeted. Yeast (Saccharomyces cerevisiae) has been developed as a surrogate host for tomato bushy stunt virus (TBSV), allowing systematic genome-wide screens to identify both susceptibility and restriction factors for TBSV. Importantly, pro-viral or antiviral functions of several of the characterized yeast proteins have been validated in plant hosts. This paper describes how yeast susceptibility and restriction factors of TBSV could be used as antiviral approaches. The gained knowledge on host factors could lead to novel, inducible, broad-range, and durable antiviral tools against plant viruses.
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Affiliation(s)
- Peter D Nagy
- Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
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9
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Arkhipov AV, Solovyev AG, Vishnichenko VK. Persistent Shallot virus X infection correlates with transcriptional repression of plant cell RNA-dependent RNA polymerase and DCL proteins in plant roots. Mol Biol 2017. [DOI: 10.1134/s0026893317010034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Moon JY, Park JM. Cross-Talk in Viral Defense Signaling in Plants. Front Microbiol 2016; 7:2068. [PMID: 28066385 PMCID: PMC5174109 DOI: 10.3389/fmicb.2016.02068] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/07/2016] [Indexed: 01/19/2023] Open
Abstract
Viruses are obligate intracellular parasites that have small genomes with limited coding capacity; therefore, they extensively use host intracellular machinery for their replication and infection in host cells. In recent years, it was elucidated that plants have evolved intricate defense mechanisms to prevent or limit damage from such pathogens. Plants employ two major strategies to counteract virus infections: resistance (R) gene-mediated and RNA silencing-based defenses. In this review, plant defenses and viral counter defenses are described, as are recent studies examining the cross-talk between different plant defense mechanisms.
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Affiliation(s)
- Ju Y. Moon
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and BiotechnologyDaejeon, South Korea
- Department of Biosystems and Bioengineering, University of Science and TechnologyDaejeon, South Korea
| | - Jeong M. Park
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and BiotechnologyDaejeon, South Korea
- Department of Biosystems and Bioengineering, University of Science and TechnologyDaejeon, South Korea
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Hashimoto M, Neriya Y, Yamaji Y, Namba S. Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors. Front Microbiol 2016; 7:1695. [PMID: 27833593 PMCID: PMC5080351 DOI: 10.3389/fmicb.2016.01695] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 10/11/2016] [Indexed: 12/13/2022] Open
Abstract
The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant’s resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF) 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species.
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Affiliation(s)
- Masayoshi Hashimoto
- Laboratory of Plant Pathology, Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo Tokyo, Japan
| | - Yutaro Neriya
- Laboratory of Plant Pathology, Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo Tokyo, Japan
| | - Yasuyuki Yamaji
- Laboratory of Plant Pathology, Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo Tokyo, Japan
| | - Shigetou Namba
- Laboratory of Plant Pathology, Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo Tokyo, Japan
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12
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Abstract
Tobacco mosaic virus and other tobamoviruses have served as models for studying the mechanisms of viral RNA replication. In tobamoviruses, genomic RNA replication occurs via several steps: (a) synthesis of viral replication proteins by translation of the genomic RNA; (b) translation-coupled binding of the replication proteins to a 5'-terminal region of the genomic RNA; (c) recruitment of the genomic RNA by replication proteins onto membranes and formation of a complex with host proteins TOM1 and ARL8; (d) synthesis of complementary (negative-strand) RNA in the complex; and (e) synthesis of progeny genomic RNA. This article reviews current knowledge on tobamovirus RNA replication, particularly regarding how the genomic RNA is specifically selected as a replication template and how the replication proteins are activated. We also focus on the roles of the replication proteins in evading or suppressing host defense systems.
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Affiliation(s)
- Kazuhiro Ishibashi
- Plant and Microbial Research Unit, Division of Plant and Microbial Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-8602, Japan ,
| | - Masayuki Ishikawa
- Plant and Microbial Research Unit, Division of Plant and Microbial Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-8602, Japan ,
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Wang WM, Liu PQ, Xu YJ, Xiao S. Protein trafficking during plant innate immunity. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:284-98. [PMID: 26345282 DOI: 10.1111/jipb.12426] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/06/2015] [Indexed: 05/20/2023]
Abstract
Plants have evolved a sophisticated immune system to fight against pathogenic microbes. Upon detection of pathogen invasion by immune receptors, the immune system is turned on, resulting in production of antimicrobial molecules including pathogenesis-related (PR) proteins. Conceivably, an efficient immune response depends on the capacity of the plant cell's protein/membrane trafficking network to deploy the right defense-associated molecules in the right place at the right time. Recent research in this area shows that while the abundance of cell surface immune receptors is regulated by endocytosis, many intracellular immune receptors, when activated, are partitioned between the cytoplasm and the nucleus for induction of defense genes and activation of programmed cell death, respectively. Vesicle transport is an essential process for secretion of PR proteins to the apoplastic space and targeting of defense-related proteins to the plasma membrane or other endomembrane compartments. In this review, we discuss the various aspects of protein trafficking during plant immunity, with a focus on the immunity proteins on the move and the major components of the trafficking machineries engaged.
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Affiliation(s)
- Wen-Ming Wang
- Rice Research Institute & Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Peng-Qiang Liu
- Rice Research Institute & Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Yong-Ju Xu
- Rice Research Institute & Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Shunyuan Xiao
- Institute for Bioscience and Biotechnology Research & Department of Plant Science and Landscape Architecture, University of Maryland, Rockville, MD, 20850, USA
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14
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Du Y, Berg J, Govers F, Bouwmeester K. Immune activation mediated by the late blight resistance protein R1 requires nuclear localization of R1 and the effector AVR1. THE NEW PHYTOLOGIST 2015; 207:735-47. [PMID: 25760731 DOI: 10.1111/nph.13355] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/03/2015] [Indexed: 05/21/2023]
Abstract
Resistance against oomycete pathogens is mainly governed by intracellular nucleotide-binding leucine-rich repeat (NLR) receptors that recognize matching avirulence (AVR) proteins from the pathogen, RXLR effectors that are delivered inside host cells. Detailed molecular understanding of how and where NLR proteins and RXLR effectors interact is essential to inform the deployment of durable resistance (R) genes. Fluorescent tags, nuclear localization signals (NLSs) and nuclear export signals (NESs) were exploited to determine the subcellular localization of the potato late blight protein R1 and the Phytophthora infestans RXLR effector AVR1, and to target these proteins to the nucleus or cytoplasm. Microscopic imaging revealed that both R1 and AVR1 occurred in the nucleus and cytoplasm, and were in close proximity. Transient expression of NLS- or NES-tagged R1 and AVR1 in Nicotiana benthamiana showed that activation of the R1-mediated hypersensitive response and resistance required localization of the R1/AVR1 pair in the nucleus. However, AVR1-mediated suppression of cell death in the absence of R1 was dependent on localization of AVR1 in the cytoplasm. Balanced nucleocytoplasmic partitioning of AVR1 seems to be a prerequisite. Our results show that R1-mediated immunity is activated inside the nucleus with AVR1 in close proximity and suggest that nucleocytoplasmic transport of R1 and AVR1 is tightly regulated.
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Affiliation(s)
- Yu Du
- Laboratory of Phytopathology, Wageningen University, Wageningen, the Netherlands
| | - Jeroen Berg
- Laboratory of Phytopathology, Wageningen University, Wageningen, the Netherlands
| | - Francine Govers
- Laboratory of Phytopathology, Wageningen University, Wageningen, the Netherlands
| | - Klaas Bouwmeester
- Laboratory of Phytopathology, Wageningen University, Wageningen, the Netherlands
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15
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Li R, Tee CS, Jiang YL, Jiang XY, Venkatesh PN, Sarojam R, Ye J. A terpenoid phytoalexin plays a role in basal defense of Nicotiana benthamiana against Potato virus X. Sci Rep 2015; 5:9682. [PMID: 25993114 PMCID: PMC4438586 DOI: 10.1038/srep09682] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/16/2015] [Indexed: 11/09/2022] Open
Abstract
Terpenoid phytoalexins function as defense compound against a broad spectrum of pathogens and pests in the plant kingdom. However, the role of phytoalexin in antiviral defense is still elusive. In this study, we identified the biosynthesis pathway of a sesquiterpenoid phytoalexin, capsidiol 3-acetate as an antiviral response against RNA virus Potato Virus X (PVX) in Nicotiana benthamiana. NbTPS1 and NbEAH genes were found strongly induced by PVX-infection. Enzymatic activity and genetic evidence indicated that both genes were involved in the PVX-induced biosynthesis of capsidiol 3-acetate. NbTPS1- or NbEAH-silenced plant was more susceptible to PVX. The accumulation of capsidiol 3-acetate in PVX-infected plant was partially regulated by jasmonic acid signaling receptor COI1. These findings provide an insight into a novel mechanism of how plant uses the basal arsenal machinery to mount a fight against virus attack even in susceptible species.
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Affiliation(s)
- Ran Li
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Chuan-Sia Tee
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Yu-Lin Jiang
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Xi-Yuan Jiang
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Prasanna Nori Venkatesh
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Rajani Sarojam
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
| | - Jian Ye
- Temasek Life Sciences Laboratory, National University of
Singapore, Singapore 117604, Singapore
- State Key Laboratory of Plant Genomics, Institute of
Microbiology, Chinese Academy of Sciences, Beijing 100101,
China
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16
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Symptom recovery in virus-infected plants: Revisiting the role of RNA silencing mechanisms. Virology 2015; 479-480:167-79. [DOI: 10.1016/j.virol.2015.01.008] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 01/02/2015] [Accepted: 01/08/2015] [Indexed: 01/11/2023]
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17
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Nicaise V. Crop immunity against viruses: outcomes and future challenges. FRONTIERS IN PLANT SCIENCE 2014; 5:660. [PMID: 25484888 PMCID: PMC4240047 DOI: 10.3389/fpls.2014.00660] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 11/04/2014] [Indexed: 05/02/2023]
Abstract
Viruses cause epidemics on all major cultures of agronomic importance, representing a serious threat to global food security. As strict intracellular pathogens, they cannot be controlled chemically and prophylactic measures consist mainly in the destruction of infected plants and excessive pesticide applications to limit the population of vector organisms. A powerful alternative frequently employed in agriculture relies on the use of crop genetic resistances, approach that depends on mechanisms governing plant-virus interactions. Hence, knowledge related to the molecular bases of viral infections and crop resistances is key to face viral attacks in fields. Over the past 80 years, great advances have been made on our understanding of plant immunity against viruses. Although most of the known natural resistance genes have long been dominant R genes (encoding NBS-LRR proteins), a vast number of crop recessive resistance genes were cloned in the last decade, emphasizing another evolutive strategy to block viruses. In addition, the discovery of RNA interference pathways highlighted a very efficient antiviral system targeting the infectious agent at the nucleic acid level. Insidiously, plant viruses evolve and often acquire the ability to overcome the resistances employed by breeders. The development of efficient and durable resistances able to withstand the extreme genetic plasticity of viruses therefore represents a major challenge for the coming years. This review aims at describing some of the most devastating diseases caused by viruses on crops and summarizes current knowledge about plant-virus interactions, focusing on resistance mechanisms that prevent or limit viral infection in plants. In addition, I will discuss the current outcomes of the actions employed to control viral diseases in fields and the future investigations that need to be undertaken to develop sustainable broad-spectrum crop resistances against viruses.
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Affiliation(s)
- Valérie Nicaise
- Fruit Biology and Pathology, Virology Laboratory, Institut National de la Recherche Agronomique, University of BordeauxUMR 1332, Villenave d’Ornon, France
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18
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Griebel T, Maekawa T, Parker JE. NOD-like receptor cooperativity in effector-triggered immunity. Trends Immunol 2014; 35:562-70. [PMID: 25308923 DOI: 10.1016/j.it.2014.09.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/16/2014] [Accepted: 09/17/2014] [Indexed: 10/24/2022]
Abstract
Intracellular nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) are basic elements of innate immunity in plants and animals. Whereas animal NLRs react to conserved microbe- or damage-associated molecular patterns, plant NLRs intercept the actions of diverse pathogen virulence factors (effectors). In this review, we discuss recent genetic and molecular evidence for functional NLR pairs, and discuss the significance of NLR self-association and heteromeric NLR assemblies in the triggering of downstream signaling pathways. We highlight the versatility and impact of cooperating NLR pairs that combine pathogen sensing with the initiation of defense signaling in both plant and animal immunity. We propose that different NLR receptor molecular configurations provide opportunities for fine-tuning resistance pathways and enhancing the host's pathogen recognition spectrum to keep pace with rapidly evolving microbial populations.
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Affiliation(s)
- Thomas Griebel
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Takaki Maekawa
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Jane E Parker
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
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