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Jovanović I, Frantová N, Zouhar J. A sword or a buffet: plant endomembrane system in viral infections. FRONTIERS IN PLANT SCIENCE 2023; 14:1226498. [PMID: 37636115 PMCID: PMC10453817 DOI: 10.3389/fpls.2023.1226498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023]
Abstract
The plant endomembrane system is an elaborate collection of membrane-bound compartments that perform distinct tasks in plant growth and development, and in responses to abiotic and biotic stresses. Most plant viruses are positive-strand RNA viruses that remodel the host endomembrane system to establish intricate replication compartments. Their fundamental role is to create optimal conditions for viral replication, and to protect replication complexes and the cell-to-cell movement machinery from host defenses. In addition to the intracellular antiviral defense, represented mainly by RNA interference and effector-triggered immunity, recent findings indicate that plant antiviral immunity also includes membrane-localized receptor-like kinases that detect viral molecular patterns and trigger immune responses, which are similar to those observed for bacterial and fungal pathogens. Another recently identified part of plant antiviral defenses is executed by selective autophagy that mediates a specific degradation of viral proteins, resulting in an infection arrest. In a perpetual tug-of-war, certain host autophagy components may be exploited by viral proteins to support or protect an effective viral replication. In this review, we present recent advances in the understanding of the molecular interplay between viral components and plant endomembrane-associated pathways.
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Affiliation(s)
- Ivana Jovanović
- Department of Crop Science, Breeding and Plant Medicine, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Nicole Frantová
- Department of Crop Science, Breeding and Plant Medicine, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Jan Zouhar
- Central European Institute of Technology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
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2
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Vermeulen A, Takken FLW, Sánchez-Camargo VA. Translation Arrest: A Key Player in Plant Antiviral Response. Genes (Basel) 2023; 14:1293. [PMID: 37372472 DOI: 10.3390/genes14061293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/15/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Plants evolved several mechanisms to protect themselves against viruses. Besides recessive resistance, where compatible host factors required for viral proliferation are absent or incompatible, there are (at least) two types of inducible antiviral immunity: RNA silencing (RNAi) and immune responses mounted upon activation of nucleotide-binding domain leucine-rich repeat (NLR) receptors. RNAi is associated with viral symptom recovery through translational repression and transcript degradation following recognition of viral double-stranded RNA produced during infection. NLR-mediated immunity is induced upon (in)direct recognition of a viral protein by an NLR receptor, triggering either a hypersensitive response (HR) or an extreme resistance response (ER). During ER, host cell death is not apparent, and it has been proposed that this resistance is mediated by a translational arrest (TA) of viral transcripts. Recent research indicates that translational repression plays a crucial role in plant antiviral resistance. This paper reviews current knowledge on viral translational repression during viral recovery and NLR-mediated immunity. Our findings are summarized in a model detailing the pathways and processes leading to translational arrest of plant viruses. This model can serve as a framework to formulate hypotheses on how TA halts viral replication, inspiring new leads for the development of antiviral resistance in crops.
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Affiliation(s)
- Annemarie Vermeulen
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS), University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Frank L W Takken
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS), University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Victor A Sánchez-Camargo
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS), University of Amsterdam, 1098 XH Amsterdam, The Netherlands
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3
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Marash I, Leibman‐Markus M, Gupta R, Avni A, Bar M. TOR inhibition primes immunity and pathogen resistance in tomato in a salicylic acid-dependent manner. MOLECULAR PLANT PATHOLOGY 2022; 23:1035-1047. [PMID: 35441436 PMCID: PMC9190978 DOI: 10.1111/mpp.13207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 02/08/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
All organisms need to sense and process information about the availability of nutrients, energy status, and environmental cues to determine the best time for growth and development. The conserved target of rapamycin (TOR) protein kinase has a central role in sensing and perceiving nutritional information. TOR connects environmental information about nutrient availability to developmental and metabolic processes to maintain cellular homeostasis. Under favourable energy conditions, TOR is activated and promotes anabolic processes such as cell division, while suppressing catabolic processes. Conversely, when nutrients are limited or environmental stresses are present, TOR is inactivated, and catabolic processes are promoted. Given the central role of TOR in regulating metabolism, several previous works have examined whether TOR is wired to plant defence. To date, the mechanisms by which TOR influences plant defence are not entirely clear. Here, we addressed this question by testing the effect of inhibiting TOR on immunity and pathogen resistance in tomato. Examining which hormonal defence pathways are influenced by TOR, we show that tomato immune responses and disease resistance to several pathogens increase on TOR inhibition, and that TOR inhibition-mediated resistance probably requires a functional salicylic acid, but not jasmonic acid, pathway. Our results support the notion that TOR is a master regulator of the development-defence switch in plants.
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Affiliation(s)
- Iftah Marash
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Meirav Leibman‐Markus
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Rupali Gupta
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Adi Avni
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Maya Bar
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
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Nothnagel T, König J, Keilwagen J, Graner EM, Plieske J, Budahn H. Transfer of the Dominant Virus Resistance Gene AV-1 pro From Asparagus prostratus to Chromosome 2 of Garden Asparagus A. officinalis L. FRONTIERS IN PLANT SCIENCE 2022; 12:809069. [PMID: 35251064 PMCID: PMC8895299 DOI: 10.3389/fpls.2021.809069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
An introgression breeding programme was carried out to transfer the virus resistance gene AV-1 pro from the wild species Asparagus prostratus to the garden asparagus Asparagus officinalis. Serious crossing barriers caused by genetic distance and different ploidy levels of the crossing parents have been overcome using embryo rescue for the F1, BC1, and BC2 generations. The male and female fertility was widely restored in BC2 and was shown to be comparable to the cultivated asparagus. Five AV-1 resistant diploid (2n = 2x = 20) BC2 plants were selected and reciprocally backcrossed with asparagus cultivars. Segregation analyses of fourteen seedborne BC3 progenies suggested a monogenic dominant inheritance of the AV-1 resistance. Genotyping by sequencing analysis gave a strong hint for location of the resistance gene on asparagus Chromosome 2. Using an Axiom single nucleotide polymorphism (SNP) genotyping array for the analysis of three BC3 families with 10 AV-1 resistant and 10 AV-1 susceptible plants each, as well as 25 asparagus cultivars, the AV-1 pro locus on Chromosome 2 was further narrowed down. The SNP with the highest LOD score was converted to a kompetitive allele specific PCR (KASP) marker, shown to be useful for the further backcross programme and serving as the starting point for the development of a diagnostic marker.
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Affiliation(s)
- Thomas Nothnagel
- Institute for Breeding Research on Horticultural Crops, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut, Quedlinburg, Germany
| | - Janine König
- Institute for Breeding Research on Horticultural Crops, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut, Quedlinburg, Germany
| | - Jens Keilwagen
- Institute for Biosafety in Plant Biotechnology, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut, Quedlinburg, Germany
| | - Eva-Maria Graner
- SGS INSTITUT FRESENIUS GmbH, TraitGenetics Section, Gatersleben, Germany
| | - Jörg Plieske
- SGS INSTITUT FRESENIUS GmbH, TraitGenetics Section, Gatersleben, Germany
| | - Holger Budahn
- Institute for Breeding Research on Horticultural Crops, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut, Quedlinburg, Germany
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da Silva VCH, Martins MCM, Calderan-Rodrigues MJ, Artins A, Monte Bello CC, Gupta S, Sobreira TJP, Riaño-Pachón DM, Mafra V, Caldana C. Shedding Light on the Dynamic Role of the "Target of Rapamycin" Kinase in the Fast-Growing C 4 Species Setaria viridis, a Suitable Model for Biomass Crops. FRONTIERS IN PLANT SCIENCE 2021; 12:637508. [PMID: 33927734 PMCID: PMC8078139 DOI: 10.3389/fpls.2021.637508] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
The Target of Rapamycin (TOR) kinase pathway integrates energy and nutrient availability into metabolism promoting growth in eukaryotes. The overall higher efficiency on nutrient use translated into faster growth rates in C4 grass plants led to the investigation of differential transcriptional and metabolic responses to short-term chemical TOR complex (TORC) suppression in the model Setaria viridis. In addition to previously described responses to TORC inhibition (i.e., general growth arrest, translational repression, and primary metabolism reprogramming) in Arabidopsis thaliana (C3), the magnitude of changes was smaller in S. viridis, particularly regarding nutrient use efficiency and C allocation and partitioning that promote biosynthetic growth. Besides photosynthetic differences, S. viridis and A. thaliana present several specificities that classify them into distinct lineages, which also contribute to the observed alterations mediated by TOR. Indeed, cell wall metabolism seems to be distinctly regulated according to each cell wall type, as synthesis of non-pectic polysaccharides were affected in S. viridis, whilst assembly and structure in A. thaliana. Our results indicate that the metabolic network needed to achieve faster growth seems to be less stringently controlled by TORC in S. viridis.
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Affiliation(s)
| | | | | | - Anthony Artins
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | | | - Saurabh Gupta
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany
| | | | | | - Valéria Mafra
- National Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Camila Caldana
- National Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
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6
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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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7
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Mugume Y, Kazibwe Z, Bassham DC. Target of Rapamycin in Control of Autophagy: Puppet Master and Signal Integrator. Int J Mol Sci 2020; 21:ijms21218259. [PMID: 33158137 PMCID: PMC7672647 DOI: 10.3390/ijms21218259] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023] Open
Abstract
The target of rapamycin (TOR) is an evolutionarily-conserved serine/threonine kinase that senses and integrates signals from the environment to coordinate developmental and metabolic processes. TOR senses nutrients, hormones, metabolites, and stress signals to promote cell and organ growth when conditions are favorable. However, TOR is inhibited when conditions are unfavorable, promoting catabolic processes such as autophagy. Autophagy is a macromolecular degradation pathway by which cells degrade and recycle cytoplasmic materials. TOR negatively regulates autophagy through phosphorylation of ATG13, preventing activation of the autophagy-initiating ATG1-ATG13 kinase complex. Here we review TOR complex composition and function in photosynthetic and non-photosynthetic organisms. We also review recent developments in the identification of upstream TOR activators and downstream effectors of TOR. Finally, we discuss recent developments in our understanding of the regulation of autophagy by TOR in photosynthetic organisms.
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8
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Brunkard JO. Exaptive Evolution of Target of Rapamycin Signaling in Multicellular Eukaryotes. Dev Cell 2020; 54:142-155. [PMID: 32649861 PMCID: PMC7346820 DOI: 10.1016/j.devcel.2020.06.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/12/2020] [Accepted: 06/18/2020] [Indexed: 12/16/2022]
Abstract
Target of rapamycin (TOR) is a protein kinase that coordinates metabolism with nutrient and energy availability in eukaryotes. TOR and its primary interactors, RAPTOR and LST8, have been remarkably evolutionarily static since they arose in the unicellular last common ancestor of plants, fungi, and animals, but the upstream regulatory mechanisms and downstream effectors of TOR signaling have evolved considerable diversity in these separate lineages. Here, I focus on the roles of exaptation and adaptation in the evolution of novel signaling axes in the TOR network in multicellular eukaryotes, concentrating especially on amino acid sensing, cell-cell signaling, and cell differentiation.
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Affiliation(s)
- Jacob O. Brunkard
- Department of Plant and Microbial Biology, University of California at Berkeley, Berkeley, CA 94720, USA,Plant Gene Expression Center, U.S. Department of Agriculture Agricultural Research Service, Albany, CA 94710, USA,Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA,Corresponding author
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9
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Hyodo K, Okuno T. Hijacking of host cellular components as proviral factors by plant-infecting viruses. Adv Virus Res 2020; 107:37-86. [PMID: 32711734 DOI: 10.1016/bs.aivir.2020.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Plant viruses are important pathogens that cause serious crop losses worldwide. They are obligate intracellular parasites that commandeer a wide array of proteins, as well as metabolic resources, from infected host cells. In the past two decades, our knowledge of plant-virus interactions at the molecular level has exploded, which provides insights into how plant-infecting viruses co-opt host cellular machineries to accomplish their infection. Here, we review recent advances in our understanding of how plant viruses divert cellular components from their original roles to proviral functions. One emerging theme is that plant viruses have versatile strategies that integrate a host factor that is normally engaged in plant defense against invading pathogens into a viral protein complex that facilitates viral infection. We also highlight viral manipulation of cellular key regulatory systems for successful virus infection: posttranslational protein modifications for fine control of viral and cellular protein dynamics; glycolysis and fermentation pathways to usurp host resources, and ion homeostasis to create a cellular environment that is beneficial for viral genome replication. A deeper understanding of viral-infection strategies will pave the way for the development of novel antiviral strategies.
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Affiliation(s)
- Kiwamu Hyodo
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan.
| | - Tetsuro Okuno
- Department of Plant Life Science, Faculty of Agriculture, Ryukoku University, Otsu, Shiga, Japan
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Ryabova LA, Robaglia C, Meyer C. Target of Rapamycin kinase: central regulatory hub for plant growth and metabolism. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2211-2216. [PMID: 30984977 PMCID: PMC6463030 DOI: 10.1093/jxb/erz108] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- Lyubov A Ryabova
- Institut de Biologie Moléculaire des Plantes, UPR 2357 CNRS, Université de Strasbourg, Strasbourg, France
| | - Christophe Robaglia
- Laboratoire de Génétique et Biophysique des Plantes, UMR 7265, Aix Marseille Université, CEA, CNRS, BIAM, Faculté des Sciences de Luminy, Marseille, France
| | - Christian Meyer
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles, France
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11
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Montané MH, Menand B. TOR inhibitors: from mammalian outcomes to pharmacogenetics in plants and algae. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2297-2312. [PMID: 30773593 DOI: 10.1093/jxb/erz053] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/05/2019] [Indexed: 05/19/2023]
Abstract
Target of rapamycin (TOR) is a conserved eukaryotic phosphatidylinositol 3-kinase-related kinase that regulates growth and metabolism in response to environment in plants and algae. The study of the plant and algal TOR pathway has largely depended on TOR inhibitors first developed for non-photosynthetic eukaryotes. In animals and yeast, fundamental work on the TOR pathway has benefited from the allosteric TOR inhibitor rapamycin and more recently from ATP-competitive TOR inhibitors (asTORis) that circumvent the limitations of rapamycin. The asTORis, developed for medical application, inhibit TOR complex 1 (TORC1) more efficiently than rapamycin and also inhibit rapamycin-resistant TORCs. This review presents knowledge on TOR inhibitors from the mammalian field and underlines important considerations for plant and algal biologists. It discusses the use of rapamycin and asTORis in plants and algae and concludes with guidelines for physiological studies and genetic screens with TOR inhibitors.
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Affiliation(s)
- Marie-Hélène Montané
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
| | - Benoît Menand
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
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12
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Margalha L, Confraria A, Baena-González E. SnRK1 and TOR: modulating growth-defense trade-offs in plant stress responses. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2261-2274. [PMID: 30793201 DOI: 10.1093/jxb/erz066] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/07/2019] [Indexed: 05/11/2023]
Abstract
The evolutionarily conserved protein kinase complexes SnRK1 and TOR are central metabolic regulators essential for plant growth, development, and stress responses. They are activated by opposite signals, and the outcome of their activation is, in global terms, antagonistic. Similarly to their yeast and animal counterparts, SnRK1 is activated by the energy deficit often associated with stress to restore homeostasis, while TOR is activated in nutrient-rich conditions to promote growth. Recent evidence suggests that SnRK1 represses TOR in plants, revealing evolutionary conservation also in their crosstalk. Given their importance for integrating environmental information into growth and developmental programs, these signaling pathways hold great promise for reducing the growth penalties caused by stress. Here we review the literature connecting SnRK1 and TOR to plant stress responses. Although SnRK1 and TOR emerge mostly as positive regulators of defense and growth, respectively, the outcome of their activities in plant growth and performance is not always straightforward. Manipulation of both pathways under similar experimental setups, as well as further biochemical and genetic analyses of their molecular and functional interaction, is essential to fully understand the mechanisms through which these two metabolic pathways contribute to stress responses, growth, and development.
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Affiliation(s)
- Leonor Margalha
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande,Oeiras, Portugal
| | - Ana Confraria
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande,Oeiras, Portugal
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Barrada A, Djendli M, Desnos T, Mercier R, Robaglia C, Montané MH, Menand B. A TOR-YAK1 signaling axis controls cell cycle, meristem activity and plant growth in Arabidopsis. Development 2019; 146:dev.171298. [PMID: 30705074 DOI: 10.1242/dev.171298] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 01/14/2019] [Indexed: 01/20/2023]
Abstract
TARGET OF RAPAMYCIN (TOR) is a conserved eukaryotic phosphatidylinositol-3-kinase-related kinase that plays a major role in regulating growth and metabolism in response to environment in plants. We performed a genetic screen for Arabidopsis ethylmethane sulfonate mutants resistant to the ATP-competitive TOR inhibitor AZD-8055 to identify new components of the plant TOR pathway. We found that loss-of-function mutants of the DYRK (dual specificity tyrosine phosphorylation regulated kinase)/YAK1 kinase are resistant to AZD-8055 and, reciprocally, that YAK1 overexpressors are hypersensitive to AZD-8055. Significantly, these phenotypes were conditional on TOR inhibition, positioning YAK1 activity downstream of TOR. We further show that the ATP-competitive DYRK1A inhibitor pINDY phenocopies YAK1 loss of function. Microscopy analysis revealed that YAK1 functions to repress meristem size and induce differentiation. We show that YAK1 represses cyclin expression in the different zones of the root meristem and that YAK1 is essential for TOR-dependent transcriptional regulation of the plant-specific SIAMESE-RELATED (SMR) cyclin-dependent kinase inhibitors in both meristematic and differentiating root cells. Thus, YAK1 is a major regulator of meristem activity and cell differentiation downstream of TOR.
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Affiliation(s)
- Adam Barrada
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, Marseille, France F-13009
| | - Meriem Djendli
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, Marseille, France F-13009
| | - Thierry Desnos
- Aix Marseille Univ, CEA, CNRS, BIAM, Laboratoire de Biologie du Développement des Plantes, Saint Paul-Lez-Durance, France F-13108
| | - Raphael Mercier
- Institut Jean-Pierre Bourgin (IJPB), Institut National de la Recherche Agronomique, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France
| | - Christophe Robaglia
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, Marseille, France F-13009
| | - Marie-Hélène Montané
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, Marseille, France F-13009
| | - Benoît Menand
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, Marseille, France F-13009
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14
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Wrzesińska B, Dai Vu L, Gevaert K, De Smet I, Obrępalska-Stęplowska A. Peanut Stunt Virus and Its Satellite RNA Trigger Changes in Phosphorylation in N. benthamiana Infected Plants at the Early Stage of the Infection. Int J Mol Sci 2018; 19:E3223. [PMID: 30340407 PMCID: PMC6214028 DOI: 10.3390/ijms19103223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/11/2018] [Accepted: 10/16/2018] [Indexed: 11/16/2022] Open
Abstract
Signaling in host plants is an integral part of a successful infection by pathogenic RNA viruses. Therefore, identifying early signaling events in host plants that play an important role in establishing the infection process will help our understanding of the disease process. In this context, phosphorylation constitutes one of the most important post-translational protein modifications, regulating many cellular signaling processes. In this study, we aimed to identify the processes affected by infection with Peanut stunt virus (PSV) and its satellite RNA (satRNA) in Nicotiana benthamiana at the early stage of pathogenesis. To achieve this, we performed proteome and phosphoproteome analyses on plants treated with PSV and its satRNA. The analysis of the number of differentially phosphorylated proteins showed strong down-regulation in phosphorylation in virus-treated plants (without satRNA). Moreover, proteome analysis revealed more down-regulated proteins in PSV and satRNA-treated plants, which indicated a complex dependence between proteins and their modifications. Apart from changes in photosynthesis and carbon metabolism, which are usually observed in virus-infected plants, alterations in proteins involved in RNA synthesis, transport, and turnover were observed. As a whole, this is the first community (phospho)proteome resource upon infection of N. benthamiana with a cucumovirus and its satRNA and this resource constitutes a valuable data set for future studies.
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Affiliation(s)
- Barbara Wrzesińska
- Institute of Plant Protection-National Research Institute, Department of Entomology, Animal Pests and Biotechnology, Władysława Węgorka 20, 60-318 Poznań, Poland.
| | - Lam Dai Vu
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Ghent, Belgium.
- VIB Center for Plant Systems Biology, Technologiepark 927, 9052 Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium.
- VIB Center for Medical Biotechnology, B-9000 Ghent, Belgium.
| | - Kris Gevaert
- Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium.
- VIB Center for Medical Biotechnology, B-9000 Ghent, Belgium.
| | - Ive De Smet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Ghent, Belgium.
- VIB Center for Plant Systems Biology, Technologiepark 927, 9052 Ghent, Belgium.
| | - Aleksandra Obrępalska-Stęplowska
- Institute of Plant Protection-National Research Institute, Department of Entomology, Animal Pests and Biotechnology, Władysława Węgorka 20, 60-318 Poznań, Poland.
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15
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Inaba JI, Nagy PD. Tombusvirus RNA replication depends on the TOR pathway in yeast and plants. Virology 2018; 519:207-222. [PMID: 29734044 DOI: 10.1016/j.virol.2018.04.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/09/2018] [Accepted: 04/15/2018] [Indexed: 02/06/2023]
Abstract
Similar to other (+)RNA viruses, tomato bushy stunt virus (TBSV) utilizes metabolites, lipids, membranes, and co-opted host factors during replication. The coordination of cell metabolism and growth with environmental cues is performed by the target of rapamycin (TOR) kinase in eukaryotic cells. In this paper, we find that TBSV replication partially inhibits TOR activity, likely due to recruitment of glycolytic enzymes to the viral replication compartment, which results in reduced ATP levels in the cytosol. Complete inhibition of TOR activity with rapamycin in yeast or AZD8055 inhibitor in plants reduces tombusvirus replication. We find that high glucose concentration, which stimulates TOR activity, enhanced tombusvirus replication in yeast. Depletion of yeast Sch9 or plant S6K1 kinase, a downstream effector of TOR, also inhibited tombusvirus replication in yeast and plant or the assembly of the viral replicase in vitro. Altogether, the TOR pathway is crucial for TBSV to replicate efficiently in hosts.
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Affiliation(s)
- Jun-Ichi Inaba
- Department of Plant Pathology, University of Kentucky, Plant Science Building, Lexington, KY 40546, United States
| | - Peter D Nagy
- Department of Plant Pathology, University of Kentucky, Plant Science Building, Lexington, KY 40546, United States.
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16
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Aznar NR, Consolo VF, Salerno GL, Martínez-Noël GM. TOR signaling downregulation increases resistance to the cereal killer Fusarium graminearum. PLANT SIGNALING & BEHAVIOR 2018; 13:e1414120. [PMID: 29227194 PMCID: PMC5846550 DOI: 10.1080/15592324.2017.1414120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/22/2017] [Accepted: 11/27/2017] [Indexed: 05/22/2023]
Abstract
TOR is the master regulator of growth and development that senses energy availability. Biotic stress perturbs metabolic and energy homeostasis, making TOR a good candidate to participate in the plant response. Fusarium graminearum (Fusarium) produces important losses in many crops all over the world. To date, the role of TOR in Fusarium infection has remained unexplored. Here, we show that the resistance to the pathogen increases in different Arabidopsis mutants impaired in TOR complex or in wild-type plants treated with a TOR inhibitor. We conclude that TOR signaling is involved in plant defense against Fusarium.
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Affiliation(s)
- Néstor R. Aznar
- Instituto de Investigaciones en Biodiversidad y Biotecnología (INBIOTEC-CONICET) and Centro de Investigaciones Biológicas (CIB-FIBA), Mar del Plata, Argentina
| | - V. Fabiana Consolo
- Instituto de Investigaciones en Biodiversidad y Biotecnología (INBIOTEC-CONICET) and Centro de Investigaciones Biológicas (CIB-FIBA), Mar del Plata, Argentina
| | - Graciela L. Salerno
- Instituto de Investigaciones en Biodiversidad y Biotecnología (INBIOTEC-CONICET) and Centro de Investigaciones Biológicas (CIB-FIBA), Mar del Plata, Argentina
| | - Giselle M.A. Martínez-Noël
- Instituto de Investigaciones en Biodiversidad y Biotecnología (INBIOTEC-CONICET) and Centro de Investigaciones Biológicas (CIB-FIBA), Mar del Plata, Argentina
- CONTACT Giselle M.A. Martínez-Noël INBIOTEC-CONICET, Vieytes 3103, 7600, Mar del Plata, Argentina
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17
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Soprano AS, Smetana JHC, Benedetti CE. Regulation of tRNA biogenesis in plants and its link to plant growth and response to pathogens. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1861:344-353. [PMID: 29222070 DOI: 10.1016/j.bbagrm.2017.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/29/2017] [Accepted: 12/03/2017] [Indexed: 12/23/2022]
Abstract
The field of tRNA biology, encompassing the functional and structural complexity of tRNAs, has fascinated scientists over the years and is continuously growing. Besides their fundamental role in protein translation, new evidence indicates that tRNA-derived molecules also regulate gene expression and protein synthesis in all domains of life. This review highlights some of the recent findings linking tRNA transcription and modification with plant cell growth and response to pathogens. In fact, mutations in proteins directly involved in tRNA synthesis and modification most often lead to pleiotropic effects on plant growth and immunity. As plants need to optimize and balance their energy and nutrient resources towards growth and defense, regulatory pathways that play a central role in integrating tRNA transcription and protein translation with cell growth control and organ development, such as the auxin-TOR signaling pathway, also influence the plant immune response against pathogens. As a consequence, distinct pathogens employ an array of effector molecules including tRNA fragments to target such regulatory pathways to exploit the plant's translational capacity, gain access to nutrients and evade defenses. An example includes the RNA polymerase III repressor MAF1, a conserved component of the TOR signaling pathway that controls ribosome biogenesis and tRNA synthesis required for plant growth and which is targeted by a pathogen effector molecule to promote disease. This article is part of a Special Issue entitled: SI: Regulation of tRNA synthesis and modification in physiological conditions and disease edited by Dr. Boguta Magdalena.
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Affiliation(s)
- Adriana Santos Soprano
- Brazilian Nacional Biosciences Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-100 Campinas, SP, Brazil
| | - Juliana Helena Costa Smetana
- Brazilian Nacional Biosciences Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-100 Campinas, SP, Brazil
| | - Celso Eduardo Benedetti
- Brazilian Nacional Biosciences Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-100 Campinas, SP, Brazil.
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18
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Hofius D, Li L, Hafrén A, Coll NS. Autophagy as an emerging arena for plant-pathogen interactions. CURRENT OPINION IN PLANT BIOLOGY 2017; 38:117-123. [PMID: 28545004 DOI: 10.1016/j.pbi.2017.04.017] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/25/2017] [Indexed: 05/20/2023]
Abstract
Autophagy is a highly conserved degradation and recycling process that controls cellular homeostasis, stress adaptation, and programmed cell death in eukaryotes. Emerging evidence indicates that autophagy is a key regulator of plant innate immunity and contributes with both pro-death and pro-survival functions to antimicrobial defences, depending on the pathogenic lifestyle. In turn, several pathogens have co-opted and evolved strategies to manipulate host autophagy pathways to the benefit of infection, while some eukaryotic microbes require their own autophagy machinery for successful pathogenesis. In this review, we present and discuss recent advances that exemplify the important role of pro- and antimicrobial autophagy in plant-pathogen interactions.
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Affiliation(s)
- Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center of Plant Biology, SE-75007 Uppsala, Sweden.
| | - Liang Li
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles, 08193 Catalonia, Spain
| | - Anders Hafrén
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center of Plant Biology, SE-75007 Uppsala, Sweden
| | - Nuria S Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles, 08193 Catalonia, Spain.
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19
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Dobrenel T, Caldana C, Hanson J, Robaglia C, Vincentz M, Veit B, Meyer C. TOR Signaling and Nutrient Sensing. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:261-85. [PMID: 26905651 DOI: 10.1146/annurev-arplant-043014-114648] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
All living organisms rely on nutrients to sustain cell metabolism and energy production, which in turn need to be adjusted based on available resources. The evolutionarily conserved target of rapamycin (TOR) protein kinase is a central regulatory hub that connects environmental information about the quantity and quality of nutrients to developmental and metabolic processes in order to maintain cellular homeostasis. TOR is activated by both nitrogen and carbon metabolites and promotes energy-consuming processes such as cell division, mRNA translation, and anabolism in times of abundance while repressing nutrient remobilization through autophagy. In animals and yeasts, TOR acts antagonistically to the starvation-induced AMP-activated kinase (AMPK)/sucrose nonfermenting 1 (Snf1) kinase, called Snf1-related kinase 1 (SnRK1) in plants. This review summarizes the immense knowledge on the relationship between TOR signaling and nutrients in nonphotosynthetic organisms and presents recent findings in plants that illuminate the crucial role of this pathway in conveying nutrient-derived signals and regulating many aspects of metabolism and growth.
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Affiliation(s)
- Thomas Dobrenel
- Institut Jean-Pierre Bourgin, UMR 1318 INRA AgroParisTech, ERL CNRS 3559, Saclay Plant Sciences, Versailles 78026, France;
- Umeå Plant Science Center, Department of Plant Physiology, Umeå University, Umeå 90187, Sweden
| | - Camila Caldana
- Molecular Physiology of Plant Biomass Production Group, Max Planck Partner Group, Brazilian Bioethanol Science and Technology Laboratory, CEP 13083-100 Campinas, São Paulo, Brazil
| | - Johannes Hanson
- Umeå Plant Science Center, Department of Plant Physiology, Umeå University, Umeå 90187, Sweden
| | - Christophe Robaglia
- Laboratoire de Génétique et Biophysique des Plantes, UMR 7265, DSV, IBEB, SBVME, CEA, CNRS, Aix Marseille Université, Faculté des Sciences de Luminy, Marseille 13009, France
| | - Michel Vincentz
- Laboratório de Genética de Plantas, Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, CEP 13083-875 Campinas, São Paulo, Brazil
| | - Bruce Veit
- Forage Improvement, AgResearch, Institute of Fundamental Sciences, Massey University, Palmerston North 4442, New Zealand
| | - Christian Meyer
- Institut Jean-Pierre Bourgin, UMR 1318 INRA AgroParisTech, ERL CNRS 3559, Saclay Plant Sciences, Versailles 78026, France;
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20
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Xiong Y, Sheen J. Novel links in the plant TOR kinase signaling network. CURRENT OPINION IN PLANT BIOLOGY 2015; 28:83-91. [PMID: 26476687 PMCID: PMC4612364 DOI: 10.1016/j.pbi.2015.09.006] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 09/18/2015] [Accepted: 09/25/2015] [Indexed: 05/18/2023]
Abstract
Nutrient and energy sensing and signaling mechanisms constitute the most ancient and fundamental regulatory networks to control growth and development in all life forms. The target of rapamycin (TOR) protein kinase is modulated by diverse nutrient, energy, hormone and stress inputs and plays a central role in regulating cell proliferation, growth, metabolism and stress responses from yeasts to plants and animals. Recent chemical, genetic, genomic and metabolomic analyses have enabled significant progress toward molecular understanding of the TOR signaling network in multicellular plants. This review discusses the applications of new chemical tools to probe plant TOR functions and highlights recent findings and predictions on TOR-mediate biological processes. Special focus is placed on novel and evolutionarily conserved TOR kinase effectors as positive and negative signaling regulators that control transcription, translation and metabolism to support cell proliferation, growth and maintenance from embryogenesis to senescence in the plant system.
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Affiliation(s)
- Yan Xiong
- Shanghai Center for Plant Stress Biology, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Jen Sheen
- Department of Genetics, Harvard Medical School, USA; Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, MA 02114, USA.
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21
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Plant Translation Factors and Virus Resistance. Viruses 2015; 7:3392-419. [PMID: 26114476 PMCID: PMC4517107 DOI: 10.3390/v7072778] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 06/18/2015] [Accepted: 06/19/2015] [Indexed: 02/06/2023] Open
Abstract
Plant viruses recruit cellular translation factors not only to translate their viral RNAs but also to regulate their replication and potentiate their local and systemic movement. Because of the virus dependence on cellular translation factors, it is perhaps not surprising that many natural plant recessive resistance genes have been mapped to mutations of translation initiation factors eIF4E and eIF4G or their isoforms, eIFiso4E and eIFiso4G. The partial functional redundancy of these isoforms allows specific mutation or knock-down of one isoform to provide virus resistance without hindering the general health of the plant. New possible targets for antiviral strategies have also been identified following the characterization of other plant translation factors (eIF4A-like helicases, eIF3, eEF1A and eEF1B) that specifically interact with viral RNAs and proteins and regulate various aspects of the infection cycle. Emerging evidence that translation repression operates as an alternative antiviral RNA silencing mechanism is also discussed. Understanding the mechanisms that control the development of natural viral resistance and the emergence of virulent isolates in response to these plant defense responses will provide the basis for the selection of new sources of resistance and for the intelligent design of engineered resistance that is broad-spectrum and durable.
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