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Identification of cell populations necessary for leaf-to-leaf electrical signaling in a wounded plant. Proc Natl Acad Sci U S A 2018; 115:10178-10183. [PMID: 30228123 PMCID: PMC6176584 DOI: 10.1073/pnas.1807049115] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Numerous modes of long-distance electrical signaling exist in nature. The best known of these, axonal conduction, requires one primary cell population, i.e., neurons. In contrast, the cell types that mediate leaf-to-leaf electrical signaling in wounded plants have not been defined rigorously. Using genetic approaches, we find that two distinct populations of cells in the vasculature matrix are needed to perform this function. Surprisingly, these cells do not contact each other directly. As we further defined the plant wound response, we found that wound-induced membrane depolarizations preceded large intravasculature calcium fluxes. We reveal a two-cell-type mode of electrical signaling in leaves and discuss parallels and differences in electrical signaling outside the plant kingdom. The identity of the cell files necessary for the leaf-to-leaf transmission of wound signals plants has been debated for decades. In Arabidopsis, wounding initiates the glutamate receptor-like (GLR)–dependent propagation of membrane depolarizations that lead to defense gene activation. Using a vein extraction procedure we found pools of GLR-fusion proteins in endomembranes in phloem sieve elements and/or in xylem contact cells. Strikingly, only double mutants that eliminated GLRs from both of these spatially separated cell types strongly attenuated leaf-to-leaf electrical signaling. glr3.3 mutants were also compromised in their defense against herbivores. Since wounding is known to cause increases in cytosolic calcium, we monitored electrical signals and Ca2+ transients simultaneously. This revealed that wound-induced membrane depolarizations in the wild-type preceded cytosolic Ca2+ maxima. The axial and radial distributions of calcium fluxes were differentially affected in each glr mutant. Resolving a debate over which cell types are necessary for electrical signaling between leaves, we show that phloem sieve elements and xylem contact cells function together in this process.
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Demidchik V. ROS-Activated Ion Channels in Plants: Biophysical Characteristics, Physiological Functions and Molecular Nature. Int J Mol Sci 2018; 19:E1263. [PMID: 29690632 PMCID: PMC5979493 DOI: 10.3390/ijms19041263] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 04/02/2018] [Accepted: 04/03/2018] [Indexed: 12/16/2022] Open
Abstract
Ion channels activated by reactive oxygen species (ROS) have been found in the plasma membrane of charophyte Nitella flixilis, dicotyledon Arabidopsis thaliana, Pyrus pyrifolia and Pisum sativum, and the monocotyledon Lilium longiflorum. Their activities have been reported in charophyte giant internodes, root trichoblasts and atrichoblasts, pollen tubes, and guard cells. Hydrogen peroxide and hydroxyl radicals are major activating species for these channels. Plant ROS-activated ion channels include inwardly-rectifying, outwardly-rectifying, and voltage-independent groups. The inwardly-rectifying ROS-activated ion channels mediate Ca2+-influx for growth and development in roots and pollen tubes. The outwardly-rectifying group facilitates K⁺ efflux for the regulation of osmotic pressure in guard cells, induction of programmed cell death, and autophagy in roots. The voltage-independent group mediates both Ca2+ influx and K⁺ efflux. Most studies suggest that ROS-activated channels are non-selective cation channels. Single-channel studies revealed activation of 14.5-pS Ca2+ influx and 16-pS K⁺ efflux unitary conductances in response to ROS. The molecular nature of ROS-activated Ca2+ influx channels remains poorly understood, although annexins and cyclic nucleotide-gated channels have been proposed for this role. The ROS-activated K⁺ channels have recently been identified as products of Stellar K⁺ Outward Rectifier (SKOR) and Guard cell Outwardly Rectifying K⁺ channel (GORK) genes.
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Affiliation(s)
- Vadim Demidchik
- Department of Horticulture, School of Food Science and Engineering, Foshan University, Foshan 528000, China.
- Department of Plant Cell Biology and Bioengineering, Biological Faculty, Belarusian State University, 4 Independence Avenue, 220030 Minsk, Belarus.
- Russian Academy of Sciences, Komarov Botanical Institute, 2 Professora Popova Street, 197376 St. Petersburg, Russia.
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Wudick MM, Michard E, Oliveira Nunes C, Feijó JA. Comparing Plant and Animal Glutamate Receptors: Common Traits but Different Fates? JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:4976335. [PMID: 29684179 DOI: 10.1093/jxb/ery153] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Indexed: 06/08/2023]
Abstract
Animal ionotropic glutamate receptors (iGluRs) are ligand-gated channels whose evolution is intimately linked to the one of the nervous system, where the agonist glutamate and co-agonists glycine/D-serine act as neuro-transmitters or -modulators. While iGluRs are specialized in neuronal communication, plant glutamate receptor-like (GLR) homologues have evolved many plant-specific physiological functions, such as sperm signaling in moss, pollen tube growth, root meristem proliferation, innate immune and wound responses. GLRs have been associated with Ca2+ signaling by directly channeling its extracellular influx into the cytosol. Nevertheless, very limited information on functional properties of GLRs is available, and we mostly rely on structure/function data obtained for animal iGluRs to interpret experimental results obtained for plant GLRs. Yet, a deeper characterization and better understanding of plant GLRs is progressively unveiling original and different mode of functions when compared to their mammalian counterparts. Here, we review the function of plant GLRs comparing their predicted structure and physiological roles to the well-documented ones of iGluRs. We conclude that interpreting GLR function based on comparison to their animal counterparts calls for caution, especially when presuming physiological roles and mode of action for plant GLRs from comparison to iGluRs in peripheral, non-neuronal tissues.
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Affiliation(s)
- Michael M Wudick
- University of Maryland Dept. of Cell Biology and Molecular Genetics, MD, U.S.A
| | - Erwan Michard
- University of Maryland Dept. of Cell Biology and Molecular Genetics, MD, U.S.A
| | | | - José A Feijó
- University of Maryland Dept. of Cell Biology and Molecular Genetics, MD, U.S.A
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La Mantia J, Unda F, Douglas CJ, Mansfield SD, Hamelin R. Overexpression of AtGolS3 and CsRFS in poplar enhances ROS tolerance and represses defense response to leaf rust disease. TREE PHYSIOLOGY 2018; 38:457-470. [PMID: 28981890 DOI: 10.1093/treephys/tpx100] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 08/03/2017] [Indexed: 06/07/2023]
Abstract
Plants respond to pathogens through an orchestration of signaling events that coordinate modifications to transcriptional profiles and physiological processes. Resistance to necrotrophic pathogens often requires jasmonic acid, which antagonizes the salicylic acid dependent biotrophic defense response. Recently, myo-inositol has been shown to negatively impact salicylic acid (SA) levels and signaling, while galactinol enhances jasmonic acid (JA)-dependent induced systemic resistance to necrotrophic pathogens. To investigate the function of these compounds in biotrophic pathogen defense, we characterized the defense response of Populus alba × grandidentata overexpressing Arabidopsis GALACTINOL SYNTHASE3 (AtGolS) and Cucumber sativus RAFFINOSE SYNTHASE (CsRFS) challenged with Melampsora aecidiodes, a causative agent of poplar leaf rust disease. Relative to wild-type leaves, the overexpression of AtGolS3 and CsRFS increased accumulation of galactinol and raffinose and led to increased leaf rust infection. During the resistance response, inoculated wild-type leaves displayed reduced levels of galactinol and repressed transcript abundance of two endogenous GolS genes compared to un-inoculated wild-type leaves prior to the up-regulation of NON-EXPRESSOR OF PR1 and PATHOGENESIS-RELATED1. Transcriptome analysis and qRT-PCR validation also revealed the repression of genes participating in calcium influx, phosphatidic acid biosynthesis and signaling, and salicylic acid signaling in the transgenic lines. In contrast, enhanced tolerance to H2O2 and up-regulation of antioxidant biosynthesis genes were exhibited in the overexpression lines. Thus, we conclude that overexpression of AtGolS and CsRFS antagonizes the defense response to poplar leaf rust disease through repressing reactive oxygen species and attenuating calcium and phosphatidic acid signaling events that lead to SA defense.
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Affiliation(s)
- Jonathan La Mantia
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver BC V6T 1Z4, Canada
- United States Department of Agriculture, Wooster, OH 44691, USA
| | - Faride Unda
- Department of Wood Science, University of British Columbia, Vancouver BC V6T 1Z4, Canada
| | - Carl J Douglas
- Department of Botany, University of British Columbia, Vancouver BC V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver BC V6T 1Z4, Canada
| | - Richard Hamelin
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver BC V6T 1Z4, Canada
- Natural Resources Canada, Laurentian Forestry Center 1055 rue du P.E.P.S., Québec G1V 4C7, Canada
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55
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Claverie J, Balacey S, Lemaître-Guillier C, Brulé D, Chiltz A, Granet L, Noirot E, Daire X, Darblade B, Héloir MC, Poinssot B. The Cell Wall-Derived Xyloglucan Is a New DAMP Triggering Plant Immunity in Vitis vinifera and Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2018; 9:1725. [PMID: 30546374 PMCID: PMC6280107 DOI: 10.3389/fpls.2018.01725] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/06/2018] [Indexed: 05/20/2023]
Abstract
Damage-associated molecular patterns (DAMPs) are endogenous molecules that can activate the plant innate immunity. DAMPs can derive from the plant cell wall, which is composed of a complex mixture of cellulose, hemicellulose, and pectin polysaccharides. Fragments of pectin, called oligogalacturonides (OG), can be released after wounding or by pathogen-encoded cell wall degrading enzymes (CWDEs) such as polygalacturonases (PGs). OG are known to induce innate immune responses, including the activation of mitogen-activated protein kinases (MAPKs), production of H2O2, defense gene activation, and callose deposition. Thus, we hypothesized that xyloglucans (Xh), derived from the plant cell wall hemicellulose, could also act as an endogenous elicitor and trigger a signaling cascade similar to OG. Our results indicate that purified Xh elicit MAPK activation and immune gene expression in grapevine (Vitis vinifera) and Arabidopsis (Arabidopsis thaliana) to trigger induced resistance against necrotrophic (Botrytis cinerea) or biotrophic (Hyaloperonospora arabidopsidis) pathogens. Xh also induce resveratrol production in grapevine cell suspension and callose deposition in Arabidopsis which depends on the callose synthase PMR4. In addition, we characterized some signaling components of Xh-induced immunity using Arabidopsis mutants. Our data suggest that Xh-induced resistance against B. cinerea is dependent on the phytoalexin, salicylate, jasmonate, and ethylene pathways.
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Affiliation(s)
- Justine Claverie
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Suzanne Balacey
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | | | - Daphnée Brulé
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Annick Chiltz
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Lucie Granet
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Elodie Noirot
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Xavier Daire
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | | | - Marie-Claire Héloir
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
| | - Benoit Poinssot
- Agroécologie, Agrosup Dijon, INRA, Université Bourgogne Franche-Comté, CNRS ERL, Dijon, France
- *Correspondence: Benoit Poinssot,
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Demidchik V, Shabala S. Mechanisms of cytosolic calcium elevation in plants: the role of ion channels, calcium extrusion systems and NADPH oxidase-mediated 'ROS-Ca 2+ Hub'. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:9-27. [PMID: 32291018 DOI: 10.1071/fp16420] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/07/2016] [Indexed: 05/22/2023]
Abstract
Elevation in the cytosolic free calcium is crucial for plant growth, development and adaptation. Calcium influx into plant cells is mediated by Ca2+ depolarisation-activated, hyperpolarisation-activated and voltage-independent Ca2+-permeable channels (DACCs, HACCs and VICCs respectively). These channels are encoded by the following gene families: (1) cyclic nucleotide-gated channels (CNGCs), (2) ionotropic glutamate receptors (GLRs), (3) annexins, (4) 'mechanosensitive channels of small (MscS) conductance'-like channels (MSLs), (5) 'mid1-complementing activity' channels (MCAs), Piezo channels, and hyperosmolality-induced [Ca2+]cyt. channel 1 (OSCA1). Also, a 'tandem-pore channel1' (TPC1) catalyses Ca2+ efflux from the vacuole in response to the plasma membrane-mediated Ca2+ elevation. Recent experimental data demonstrated that Arabidopsis thaliana (L.) Heynh. CNGCs 2, 5-10, 14, 16 and 18, GLRs 1.2, 3.3, 3.4, 3.6 and 3.7, TPC1, ANNEXIN1, MSL9 and MSL10,MCA1 and MCA2, OSCA1, and some their homologues counterparts in other species, are responsible for Ca2+ currents and/or cytosolic Ca2+ elevation. Extrusion of Ca2+ from the cytosol is mediated by Ca2+-ATPases and Ca2+/H+ exchangers which were recently examined at the level of high resolution crystal structure. Calcium-activated NADPH oxidases and reactive oxygen species (ROS)-activated Ca2+ conductances form a self-amplifying 'ROS-Ca2+hub', enhancing and transducing Ca2+ and redox signals. The ROS-Ca2+ hub contributes to physiological reactions controlled by ROS and Ca2+, demonstrating synergism and unity of Ca2+ and ROS signalling mechanisms.
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Affiliation(s)
- Vadim Demidchik
- Department of Plant Cell Biology and Bioengineering, Biological Faculty, Belarusian State University, 4 Independence Avenue, Minsk, 220030, Belarus
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas. 7001, Australia
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57
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Noctor G, Mhamdi A. Climate Change, CO 2, and Defense: The Metabolic, Redox, and Signaling Perspectives. TRENDS IN PLANT SCIENCE 2017; 22:857-870. [PMID: 28811163 DOI: 10.1016/j.tplants.2017.07.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 07/04/2017] [Accepted: 07/13/2017] [Indexed: 05/20/2023]
Abstract
Ongoing human-induced changes in the composition of the atmosphere continue to stimulate interest in the effects of high CO2 on plants, but its potential impact on inducible plant defense pathways remains poorly defined. Recently, several studies have reported that growth at elevated CO2 is sufficient to induce defenses such as the salicylic acid pathway, thereby increasing plant resistance to pathogens. These reports contrast with evidence that defense pathways can be promoted by photorespiration, which is inhibited at high CO2. Here, we review signaling, metabolic, and redox processes modulated by CO2 levels and discuss issues to be resolved in elucidating the relationships between primary metabolism, inducible defense, and biotic stress resistance.
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Affiliation(s)
- Graham Noctor
- Institute of Plant Sciences Paris-Saclay (IPS2), UMR 9213/UMR1403, Université Paris-Sud, CNRS, INRA, Université d'Evry, Université Paris-Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France.
| | - Amna Mhamdi
- Institute of Plant Sciences Paris-Saclay (IPS2), UMR 9213/UMR1403, Université Paris-Sud, CNRS, INRA, Université d'Evry, Université Paris-Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France; Current address: Department of Plant Systems Biology, VIB, and Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
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58
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Ni J, Yu Z, Du G, Zhang Y, Taylor JL, Shen C, Xu J, Liu X, Wang Y, Wu Y. Heterologous Expression and Functional Analysis of Rice GLUTAMATE RECEPTOR-LIKE Family Indicates its Role in Glutamate Triggered Calcium Flux in Rice Roots. RICE (NEW YORK, N.Y.) 2016; 9:9. [PMID: 26956369 PMCID: PMC4783324 DOI: 10.1186/s12284-016-0081-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 02/20/2016] [Indexed: 05/19/2023]
Abstract
BACKGROUND Tremendous progress has been made in understanding the functions of the GLUTAMATE RECEPTOR-LIKE (GLR) family in Arabidopsis. Still, the functions of OsGLRs in rice, especially the ion channel activities, are largely unknown. RESULTS Using the aequorin-based luminescence imaging system, we screened the specificity of amino acids involved in the induction of Ca(2+) flux in rice roots. Of all the amino acids tested, glutamate (Glu) was the only one to trigger Ca(2+) flux significantly in rice roots. Detailed analysis showed a dose response of Ca(2+) increase to different concentrations of Glu. In addition, the Ca(2+) spike response to Glu was rapid, within 20 s after the application. A desensitization assay and pharmacological tests showed that the Glu-triggered Ca(2+) flux is mediated by OsGLRs. Whole genome analysis identified 13 OsGLR genes in rice, and these genes have various expression patterns in different tissues. Subcellular localization studies showed that all the OsGLRs examined are likely localized to the plasma membrane. Bacteria growth assays showed that at least OsGLR2.1 and OsGLR3.2 have the potential to mediate ion uptake in bacteria. Further analysis using Fura-2-based Ca(2+) imaging revealed a Glu-triggered Ca(2+) increase in OsGLR2.1-expressing human embryonic kidney (HEK) cells. CONCLUSIONS Our work provides a molecular basis for investigating mechanisms of Glu-triggered Ca(2+) flux in rice.
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Affiliation(s)
- Jun Ni
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Zhiming Yu
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Guankui Du
- />Department of Biochemistry, Hainan Medical College, Haikou, 571199 China
| | - Yanyan Zhang
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Jemma L. Taylor
- />School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry, CV4 7AL UK
| | - Chenjia Shen
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Jing Xu
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Xunyan Liu
- />College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310018 China
| | - Yifeng Wang
- />State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 311400 China
| | - Yunrong Wu
- />State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, 310058 China
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Choi WG, Hilleary R, Swanson SJ, Kim SH, Gilroy S. Rapid, Long-Distance Electrical and Calcium Signaling in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:287-307. [PMID: 27023742 DOI: 10.1146/annurev-arplant-043015-112130] [Citation(s) in RCA: 180] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plants integrate activities throughout their bodies using long-range signaling systems in which stimuli sensed by just a few cells are translated into mobile signals that can influence the activities in distant tissues. Such signaling can travel at speeds well in excess of millimeters per second and can trigger responses as diverse as changes in transcription and translation levels, posttranslational regulation, alterations in metabolite levels, and even wholesale reprogramming of development. In addition to the use of mobile small molecules and hormones, electrical signals have long been known to propagate throughout the plant. This electrical signaling network has now been linked to waves of Ca(2+) and reactive oxygen species that traverse the plant and trigger systemic responses. Analysis of cell type specificity in signal propagation has revealed the movement of systemic signals through specific cell types, suggesting that a rapid signaling network may be hardwired into the architecture of the plant.
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Affiliation(s)
- Won-Gyu Choi
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706; , , , ,
| | - Richard Hilleary
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706; , , , ,
| | - Sarah J Swanson
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706; , , , ,
| | - Su-Hwa Kim
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706; , , , ,
| | - Simon Gilroy
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706; , , , ,
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60
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Ranty B, Aldon D, Cotelle V, Galaud JP, Thuleau P, Mazars C. Calcium Sensors as Key Hubs in Plant Responses to Biotic and Abiotic Stresses. FRONTIERS IN PLANT SCIENCE 2016; 7:327. [PMID: 27014336 PMCID: PMC4792864 DOI: 10.3389/fpls.2016.00327] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 03/03/2016] [Indexed: 05/07/2023]
Abstract
The Ca(2+) ion is recognized as a crucial second messenger in signaling pathways coupling the perception of environmental stimuli to plant adaptive responses. Indeed, one of the earliest events following the perception of environmental changes (temperature, salt stress, drought, pathogen, or herbivore attack) is intracellular variation of free calcium concentrations. These calcium variations differ in their spatio-temporal characteristics (subcellular location, amplitude, kinetics) with the nature and strength of the stimulus and, for this reason, they are considered as signatures encrypting information from the initial stimulus. This information is believed to drive a specific response by decoding via calcium-binding proteins. Based on recent examples, we illustrate how individual calcium sensors from the calcium-dependent protein kinase and calmodulin-like protein families can integrate inputs from various environmental changes. Focusing on members of these two families, shown to be involved in plant responses to both abiotic and biotic stimuli, we discuss their role as key hubs and we put forward hypotheses explaining how they can drive the signaling pathways toward the appropriate plant responses.
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Affiliation(s)
| | | | | | | | | | - Christian Mazars
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPSAuzeville, Castanet-Tolosan, France
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61
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Kadotani N, Akagi A, Takatsuji H, Miwa T, Igarashi D. Exogenous proteinogenic amino acids induce systemic resistance in rice. BMC PLANT BIOLOGY 2016; 16:60. [PMID: 26940322 PMCID: PMC4778346 DOI: 10.1186/s12870-016-0748-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/26/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND Plant immune responses can be induced by endogenous and exogenous signaling molecules. Recently, amino acids and their metabolites have been reported to affect the plant immune system. However, how amino acids act in plant defense responses has yet to be clarified. Here, we report that treatment of rice roots with amino acids such as glutamate (Glu) induced systemic disease resistance against rice blast in leaves. RESULTS Treatment of roots with Glu activated the transcription of a large variety of defense-related genes both in roots and leaves. In leaves, salicylic acid (SA)-responsive genes, rather than jasmonic acid (JA) or ethylene (ET)-responsive genes, were induced by this treatment. The Glu-induced blast resistance was partially impaired in rice plants deficient in SA signaling such as NahG plants expressing an SA hydroxylase, WRKY45-knockdown, and OsNPR1-knockdown plants. The JA-deficient mutant cpm2 exhibited full Glu-induced blast resistance. CONCLUSIONS Our results indicate that the amino acid-induced blast resistance partly depends on the SA pathway but an unknown SA-independent signaling pathway is also involved.
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Affiliation(s)
- Naoki Kadotani
- Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan.
| | - Aya Akagi
- Plant Disease Resistance Research Unit, Division of Plant Science, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba, 305-8602, Japan.
- Bayer Crop Science, Tokyo, 100-8262, Japan.
| | - Hiroshi Takatsuji
- Plant Disease Resistance Research Unit, Division of Plant Science, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba, 305-8602, Japan.
| | - Tetsuya Miwa
- Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan.
| | - Daisuke Igarashi
- Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan.
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62
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Hamann T. The plant cell wall integrity maintenance mechanism--a case study of a cell wall plasma membrane signaling network. PHYTOCHEMISTRY 2015; 112:100-9. [PMID: 25446233 DOI: 10.1016/j.phytochem.2014.09.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/07/2014] [Accepted: 09/23/2014] [Indexed: 05/18/2023]
Abstract
Some of the most important functions of plant cell walls are protection against biotic/abiotic stress and structural support during growth and development. A prerequisite for plant cell walls to perform these functions is the ability to perceive different types of stimuli in both qualitative and quantitative manners and initiate appropriate responses. The responses in turn involve adaptive changes in cellular and cell wall metabolism leading to modifications in the structures originally required for perception. While our knowledge about the underlying plant mechanisms is limited, results from Saccharomyces cerevisiae suggest the cell wall integrity maintenance mechanism represents an excellent example to illustrate how the molecular mechanisms responsible for stimulus perception, signal transduction and integration can function. Here I will review the available knowledge about the yeast cell wall integrity maintenance system for illustration purposes, summarize the limited knowledge available about the corresponding plant mechanism and discuss the relevance of the plant cell wall integrity maintenance mechanism in biotic stress responses.
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Affiliation(s)
- Thorsten Hamann
- Department of Biology, Høgskoleringen 5, Realfagbygget, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
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63
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Trapet P, Kulik A, Lamotte O, Jeandroz S, Bourque S, Nicolas-Francès V, Rosnoblet C, Besson-Bard A, Wendehenne D. NO signaling in plant immunity: a tale of messengers. PHYTOCHEMISTRY 2015; 112:72-9. [PMID: 24713571 DOI: 10.1016/j.phytochem.2014.03.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 03/12/2014] [Indexed: 05/05/2023]
Abstract
Nitric oxide (NO) is a free radical gas involved in a myriad of plant physiological processes including immune responses. How NO mediates its biological effects in plant facing microbial pathogen attack is an unresolved question. Insights into the molecular mechanisms by which it propagates signals reveal the contribution of this simple gas in complex signaling pathways shared with reactive oxygen species (ROS) and the second messenger Ca(2+). Understanding of the subtle cross-talks operating between these signals was greatly improved by the recent identification and the functional analysis of proteins regulated through S-nitrosylation, a major NO-dependent post-translational protein modification. Overall, these findings suggest that NO is probably an important component of the mechanism coordinating and regulating Ca(2+) and ROS signaling in plant immunity.
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Affiliation(s)
- Pauline Trapet
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Anna Kulik
- INRA, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Olivier Lamotte
- CNRS, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Sylvain Jeandroz
- AgroSup Dijon, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Stéphane Bourque
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Valérie Nicolas-Francès
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Claire Rosnoblet
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - Angélique Besson-Bard
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France
| | - David Wendehenne
- Université de Bourgogne, UMR 1347 Agroécologie, BP 86510, F-21000 Dijon, France; ERL CNRS 6300, BP 86510, 21000 Dijon, France.
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Weiland M, Mancuso S, Baluska F. Signalling via glutamate and GLRs in Arabidopsis thaliana. FUNCTIONAL PLANT BIOLOGY : FPB 2015; 43:1-25. [PMID: 32480438 DOI: 10.1071/fp15109] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 10/14/2015] [Indexed: 05/14/2023]
Abstract
The genome of Arabidopsis thaliana (L. Heynh.) contains 20 coding sequences for homologues of animal ionotropic glutamate receptors. These glutamate receptor-like receptors act as sensors and mediators of a multitude of exogenous as well as endogenous signals and are found in all analysed plant species. Their molecular structure clearly indicates a function as integral membrane proteins with a ligand-gated ion channel activity. Altered gene expressions and the occurrence of mRNA splice variants confer a high flexibility on the gene as well as on the RNA level. An individual glutamate receptor of A. thaliana is able to bind two different ligands (most probable amino acids and their derivatives), whereas a functional receptor complex is likely to consist of four single proteins. These features enable an immense number of sensitivities against various local and temporal stimuli. This review encompasses the last 15 years of research concerning glutamate signalling and glutamate receptors in plants. It is aimed at summarising their major characteristics and involvements to obtain a broader and farer reaching perspective of these fundamental components of plant signal transduction.
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Affiliation(s)
- Matthias Weiland
- Department of Plant, Soil and Environmental Science, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino, Italy
| | - Stefano Mancuso
- Department of Plant, Soil and Environmental Science, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino, Italy
| | - Frantisek Baluska
- Department of Plant Cell Biology, Institute of Cellular and Molecular Botany (IZMB), University of Bonn, Kirschallee 1, 53115 Bonn, Germany
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Seybold H, Trempel F, Ranf S, Scheel D, Romeis T, Lee J. Ca2+ signalling in plant immune response: from pattern recognition receptors to Ca2+ decoding mechanisms. THE NEW PHYTOLOGIST 2014; 204:782-90. [PMID: 25539002 DOI: 10.1111/nph.13031] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Ca2+ is a ubiquitous second messenger for cellular signalling in various stresses and developmental processes. Here, we summarize current developments in the roles of Ca2+ during plant immunity responses. We discuss the early perception events preceding and necessary for triggering cellular Ca2+ fluxes, the potential Ca2+-permeable channels, the decoding of Ca2+ signals predominantly via Ca2+-dependent phosphorylation events and transcriptional reprogramming. To highlight the complexity of the cellular signal network, we briefly touch on the interplay between Ca2+-dependent signalling and selected major signalling mechanisms--with special emphasis on reactive oxygen species at local and systemic levels.
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Thor K, Peiter E. Cytosolic calcium signals elicited by the pathogen-associated molecular pattern flg22 in stomatal guard cells are of an oscillatory nature. THE NEW PHYTOLOGIST 2014; 204:873-81. [PMID: 25243759 DOI: 10.1111/nph.13064] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 08/16/2014] [Indexed: 05/18/2023]
Abstract
Changes in cytosolic free calcium ([Ca(2+)]cyt) are an early and essential element of signalling networks activated by the perception of pathogen-associated molecular patterns (PAMPs), such as flg22. The flg22-induced calcium signal has been described on whole-plant, but not on single-cell scale so far. Also, the Ca(2+) sources and channels contributing to its generation are still obscure. Ratiometric fluorescence imaging employing the calcium reporter Yellow Cameleon 3.6 was performed to analyse the flg22-induced calcium signature in single guard cells of Arabidopsis thaliana. Calcium stores and channel types involved in its generation were determined by a pharmacological approach. In contrast to the calcium signal determined on whole-plant level, the signature on single-cell level is not characterized by one sustained response, but by oscillations in [Ca(2+)]cyt. These oscillations were abolished by EGTA and lanthanum, as well as by U73122, neomycin and TMB-8, but only partially or not at all affected by inhibitors of glutamate receptor-like channels and cyclic nucleotide-gated channels. Our analyses suggest that the response observed on whole-plant level is the summary of oscillations occurring in single cells. Parallel to external calcium, influx via channels located at internal stores contributes to the signal.
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Affiliation(s)
- Kathrin Thor
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin Luther University of Halle-Wittenberg, 06099, Halle (Saale), Germany
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Steinhorst L, Kudla J. Signaling in cells and organisms - calcium holds the line. CURRENT OPINION IN PLANT BIOLOGY 2014; 22:14-21. [PMID: 25195171 DOI: 10.1016/j.pbi.2014.08.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 08/15/2014] [Accepted: 08/16/2014] [Indexed: 05/22/2023]
Abstract
Previous research has established calcium (Ca(2+)) and reactive oxygen species (ROS) as important cellular second messengers in eukaryotes. Recently, the occurrence of cell-to-cell moving Ca(2+) and ROS waves was reported in plants. This was paralleled by the discovery of long-distance wound-activated surface potential changes (WASPs) that require the function of putatively Ca(2+)-releasing glutamate receptor-like channels (GLRs) in Arabidopsis. Although the functional interconnection of Ca(2+)-dependent phosphorylation and ROS waves via NADPH oxidase activation has been clearly established, potential further interconnections between these long-distance signaling processes are less clear. In this review we cover emerging concepts and existing open questions that interconnect cellular and global signaling via Ca(2+), ROS and WASPs.
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Affiliation(s)
- Leonie Steinhorst
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 4, 48149 Münster, Germany
| | - Jörg Kudla
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 4, 48149 Münster, Germany.
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Edel KH, Kudla J. Increasing complexity and versatility: how the calcium signaling toolkit was shaped during plant land colonization. Cell Calcium 2014; 57:231-46. [PMID: 25477139 DOI: 10.1016/j.ceca.2014.10.013] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 10/27/2014] [Indexed: 12/22/2022]
Abstract
Calcium serves as a versatile messenger in adaptation reactions and developmental processes in plants and animals. Eukaryotic cells generate cytosolic Ca(2+) signals via Ca(2+) conducting channels. Ca(2+) signals are represented in form of stimulus-specific spatially and temporally defined Ca(2+) signatures. These Ca(2+) signatures are detected, decoded and transmitted to downstream responses by an elaborate toolkit of Ca(2+) binding proteins that function as Ca(2+) sensors. In this article, we examine the distribution and evolution of Ca(2+)-conducting channels and Ca(2+) decoding proteins in the plant lineage. To this end, we have in addition to previously studied genomes of plant species, identified and analyzed the Ca(2+)-signaling components from species that hold key evolutionary positions like the filamentous terrestrial algae Klebsormidium flaccidum and Amborella trichopoda, the single living representative of the sister lineage to all other extant flowering plants. Plants and animals exhibit substantial differences in their complements of Ca(2+) channels and Ca(2+) binding proteins. Within the plant lineage, remarkable differences in the evolution of complexity between different families of Ca(2+) signaling proteins are observable. Using the CBL/CIPK Ca(2+) sensor/kinase signaling network as model, we attempt to link evolutionary tendencies to functional predictions. Our analyses, for example, suggest Ca(2+) dependent regulation of Na(+) homeostasis as an evolutionary most ancient function of this signaling network. Overall, gene families of Ca(2+) signaling proteins have significantly increased in their size during plant evolution reaching an extraordinary complexity in angiosperms.
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Affiliation(s)
- Kai H Edel
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 4, 48149 Münster, Germany.
| | - Jörg Kudla
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 4, 48149 Münster, Germany; College of Science, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia.
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Sun C, Shao Y, Vahabi K, Lu J, Bhattacharya S, Dong S, Yeh KW, Sherameti I, Lou B, Baldwin IT, Oelmüller R. The beneficial fungus Piriformospora indica protects Arabidopsis from Verticillium dahliae infection by downregulation plant defense responses. BMC PLANT BIOLOGY 2014; 14:268. [PMID: 25297988 PMCID: PMC4198706 DOI: 10.1186/s12870-014-0268-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/29/2014] [Indexed: 05/21/2023]
Abstract
BACKGROUND Verticillium dahliae (Vd) is a soil-borne vascular pathogen which causes severe wilt symptoms in a wide range of plants. The microsclerotia produced by the pathogen survive in soil for more than 15 years. RESULTS Here we demonstrate that an exudate preparation induces cytoplasmic calcium elevation in Arabidopsis roots, and the disease development requires the ethylene-activated transcription factor EIN3. Furthermore, the beneficial endophytic fungus Piriformospora indica (Pi) significantly reduced Vd-mediated disease development in Arabidopsis. Pi inhibited the growth of Vd in a dual culture on PDA agar plates and pretreatment of Arabidopsis roots with Pi protected plants from Vd infection. The Pi-pretreated plants grew better after Vd infection and the production of Vd microsclerotia was dramatically reduced, all without activating stress hormones and defense genes in the host. CONCLUSIONS We conclude that Pi is an efficient biocontrol agent that protects Arabidopsis from Vd infection. Our data demonstrate that Vd growth is restricted in the presence of Pi and the additional signals from Pi must participate in the regulation of the immune response against Vd.
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Affiliation(s)
- Chao Sun
- />Institute of Plant Physiology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743 Jena, Germany
| | - Yongqi Shao
- />Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
| | - Khabat Vahabi
- />Institute of Plant Physiology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743 Jena, Germany
| | - Jing Lu
- />Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
- />Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058 China
| | - Samik Bhattacharya
- />Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
| | - Sheqin Dong
- />College of Life Sciences, Yangtze University, Jingzhou, China
| | - Kai-Wun Yeh
- />Institute of Plant Biology, National Taiwan University, Taipei, Taiwan
| | - Irena Sherameti
- />Institute of Plant Physiology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743 Jena, Germany
| | - Binggan Lou
- />Institute of Biotechnology, Zhejiang University, Hangzhou, 310058 China
| | - Ian T Baldwin
- />Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
| | - Ralf Oelmüller
- />Institute of Plant Physiology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743 Jena, Germany
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Maintz J, Cavdar M, Tamborski J, Kwaaitaal M, Huisman R, Meesters C, Kombrink E, Panstruga R. Comparative Analysis of MAMP-induced Calcium Influx in Arabidopsis Seedlings and Protoplasts. ACTA ACUST UNITED AC 2014; 55:1813-25. [DOI: 10.1093/pcp/pcu112] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Forde BG, Roberts MR. Glutamate receptor-like channels in plants: a role as amino acid sensors in plant defence? F1000PRIME REPORTS 2014; 6:37. [PMID: 24991414 PMCID: PMC4075314 DOI: 10.12703/p6-37] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Plant glutamate receptor-like genes (GLRs) are homologous to the genes for mammalian ionotropic glutamate receptors (iGluRs), after which they were named, but in the 16 years since their existence was first revealed, progress in elucidating their biological role has been disappointingly slow. Recently, however, studies from a number of laboratories focusing on the model plant species Arabidopsis thaliana (L.) have thrown new light on the functional properties of some members of the GLR gene family. One important finding has been that plant GLR receptors have a much broader ligand specificity than their mammalian iGluR counterparts, with evidence that some individual GLR receptors can be gated by as many as seven amino acids. These results, together with the ubiquity of their expression throughout the plant, open up the possibility that GLR receptors could have a pervasive role in plants as non-specific amino acid sensors in diverse biological processes. Addressing what one of these roles could be, recent studies examining the wound response and disease susceptibility in GLR knockout mutants have provided evidence that some members of clade 3 of the GLR gene family encode important components of the plant's defence response. Ways in which this family of amino acid receptors might contribute to the plant's ability to respond to an attack from pests and pathogens are discussed.
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Perlin MH, Andrews J, San Toh S. Essential Letters in the Fungal Alphabet. ADVANCES IN GENETICS 2014; 85:201-53. [DOI: 10.1016/b978-0-12-800271-1.00004-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Baluška F, Mancuso S. Root apex transition zone as oscillatory zone. FRONTIERS IN PLANT SCIENCE 2013; 4:354. [PMID: 24106493 PMCID: PMC3788588 DOI: 10.3389/fpls.2013.00354] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 08/22/2013] [Indexed: 05/17/2023]
Abstract
Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone.
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Affiliation(s)
- František Baluška
- Institute of Cellular and Molecular Botany, Department of Plant Cell Biology, University of BonnBonn, Germany
| | - Stefano Mancuso
- LINV – DiSPAA, Department of Agri-Food and Environmental Science, University of FlorenceSesto Fiorentino, Italy
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