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Arico DS, Dickmann JE, Hamant O, Canut H. The plasma membrane - cell wall nexus in plant cells: focus on the Hechtian structure. Cell Surf 2023; 10:100115. [PMID: 38024561 PMCID: PMC10663899 DOI: 10.1016/j.tcsw.2023.100115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/02/2023] [Accepted: 11/02/2023] [Indexed: 12/01/2023] Open
Abstract
Across all kingdoms of life, cells secrete an extracellular polymer mesh that in turn feeds back onto them. This entails physical connections between the plasma membrane and the polymer mesh. In plant cells, one connection stands out: the Hechtian strand which, during plasmolysis, reflects the existence of a physical link between the plasma membrane of the retracting protoplast and the cell wall. The Hechtian strand is part of a larger structure, which we call the Hechtian structure, that comprises the Hechtian strand, the Hechtian reticulum and the Hechtian attachment sites. Although it has been observed for more than 100 years, its molecular composition and biological functions remain ill-described. A comprehensive characterization of the Hechtian structure is a critical step towards understanding this plasma membrane-cell wall connection and its relevance in cell signaling. This short review intends to highlight the main features of the Hechtian structure, in order to provide a clear framework for future research in this under-explored and promising field.
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Affiliation(s)
- Denise S. Arico
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, 31320 Auzeville Tolosane, France
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, CNRS, INRAE, UCBL, Lyon, France
| | - Johanna E.M. Dickmann
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, CNRS, INRAE, UCBL, Lyon, France
| | - Olivier Hamant
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, CNRS, INRAE, UCBL, Lyon, France
| | - Hervé Canut
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, 31320 Auzeville Tolosane, France
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2
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Ma Z, Zhu K, Gao Y, Tan S, Miao Y. Molecular condensation and mechanoregulation of plant class I formin, an integrin‐like actin nucleator. FEBS J 2022. [DOI: 10.1111/febs.16571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/29/2022] [Accepted: 07/04/2022] [Indexed: 11/30/2022]
Affiliation(s)
- Zhiming Ma
- School of Biological Sciences Nanyang Technological University Singapore City Singapore
| | - Kexin Zhu
- School of Biological Sciences Nanyang Technological University Singapore City Singapore
| | - Yong‐Gui Gao
- School of Biological Sciences Nanyang Technological University Singapore City Singapore
| | - Suet‐Mien Tan
- School of Biological Sciences Nanyang Technological University Singapore City Singapore
| | - Yansong Miao
- School of Biological Sciences Nanyang Technological University Singapore City Singapore
- Institute for Digital Molecular Analytics and Science Nanyang Technological University Singapore City Singapore
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3
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Pizarro A, Díaz-Sala C. Expression Levels of Genes Encoding Proteins Involved in the Cell Wall-Plasma Membrane-Cytoskeleton Continuum Are Associated With the Maturation-Related Adventitious Rooting Competence of Pine Stem Cuttings. FRONTIERS IN PLANT SCIENCE 2021; 12:783783. [PMID: 35126413 PMCID: PMC8810826 DOI: 10.3389/fpls.2021.783783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/17/2021] [Indexed: 05/04/2023]
Abstract
Stem cutting recalcitrance to adventitious root formation is a major limitation for the clonal propagation or micropropagation of elite genotypes of many forest tree species, especially at the adult stage of development. The interaction between the cell wall-plasma membrane and cytoskeleton may be involved in the maturation-related decline of adventitious root formation. Here, pine homologs of several genes encoding proteins involved in the cell wall-plasma membrane-cytoskeleton continuum were identified, and the expression levels of 70 selected genes belonging to the aforementioned group and four genes encoding auxin carrier proteins were analyzed during adventitious root formation in rooting-competent and non-competent cuttings of Pinus radiata. Variations in the expression levels of specific genes encoding cell wall components and cytoskeleton-related proteins were detected in rooting-competent and non-competent cuttings in response to wounding and auxin treatments. However, the major correlation of gene expression with competence for adventitious root formation was detected in a family of genes encoding proteins involved in sensing the cell wall and membrane disturbances, such as specific receptor-like kinases (RLKs) belonging to the lectin-type RLKs, wall-associated kinases, Catharanthus roseus RLK1-like kinases and leucine-rich repeat RLKs, as well as downstream regulators of the small guanosine triphosphate (GTP)-binding protein family. The expression of these genes was more affected by organ and age than by auxin and time of induction.
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Molecular evidence for the involvement of cotton GhGLP2, in enhanced resistance to Verticillium and Fusarium Wilts and oxidative stress. Sci Rep 2020; 10:12510. [PMID: 32719475 PMCID: PMC7385154 DOI: 10.1038/s41598-020-68943-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/22/2020] [Indexed: 11/24/2022] Open
Abstract
Germin-like proteins (GLPs) are a diverse and ubiquitous family of plant glycoproteins belonging to the cupin super family; they play considerable roles in plant responses against various abiotic and biotic stresses. Here, we provide evidence that GLP2 protein from cotton (Gossypium hirsutum) functions in plant defense responses against Verticillium dahliae, Fusarium oxysporum and oxidative stress. Purified recombinant GhGLP2 exhibits superoxide dismutase (SOD) activity and inhibits spore germination of pathogens. Virus-induced silencing of GhGLP2 in cotton results in increased susceptibility to pathogens, plants exhibited severe wilt on leaves, enhanced vascular browning and suppressed callose deposition. Transgenic Arabidopsis (Arabidopsis thaliana) plants overexpressing GhGLP2 showed significant resistance to V. dahliae and F. oxysporum, with reduced mycelia growth, increased callose deposition and cell wall lignification at infection sites on leaves. The enhanced tolerance of GhGLP2-transgenic Arabidopsis to oxidative stress was investigated by methyl viologen and ammonium persulfate treatments, along with increased H2O2 production. Further, the expression of several defense-related genes (PDF1.2, LOX2, and VSP1) or oxidative stress-related genes (RbohD, RbohF) was triggered by GhGLP2. Thus, our results confirmed the involvement of GhGLP2 in plant defense response against Verticillium and Fusarium wilt pathogens and stress conditions.
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Abstract
Development encapsulates the morphogenesis of an organism from a single fertilized cell to a functional adult. A critical part of development is the specification of organ forms. Beyond the molecular control of morphogenesis, shape in essence entails structural constraints and thus mechanics. Revisiting recent results in biophysics and development, and comparing animal and plant model systems, we derive key overarching principles behind the formation of organs across kingdoms. In particular, we highlight how growing organs are active rather than passive systems and how such behavior plays a role in shaping the organ. We discuss the importance of considering different scales in understanding how organs form. Such an integrative view of organ development generates new questions while calling for more cross-fertilization between scientific fields and model system communities.
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Affiliation(s)
- O Hamant
- Laboratoire de Reproduction et Développement des Plantes, École normale supérieure (ENS) de Lyon, Université Claude Bernard Lyon (UCBL), Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), CNRS, Université de Lyon, 69364 Lyon, France;
| | - T E Saunders
- Mechanobiology Institute and Department of Biological Sciences, National University of Singapore, Singapore 117411; .,Institute of Molecular and Cell Biology, A*Star, Proteos, Singapore 138673
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6
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Yoneda A, Ohtani M, Katagiri D, Hosokawa Y, Demura T. Hechtian Strands Transmit Cell Wall Integrity Signals in Plant Cells. PLANTS 2020; 9:plants9050604. [PMID: 32397402 PMCID: PMC7284614 DOI: 10.3390/plants9050604] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/03/2020] [Accepted: 05/05/2020] [Indexed: 01/09/2023]
Abstract
Hechtian strands are thread-like structures in plasmolyzed plant cells that connect the cell wall to the plasma membrane. Although these strands were first observed more than 100 years ago, their physiological roles are largely unknown. Here, we used intracellular laser microdissection to examine the effects of disrupting Hechtian strands on plasmolyzed tobacco BY-2 cells. When we focused femtosecond laser pulses on Hechtian strands, targeted disruptions were induced, but no visible changes in cell morphology were detected. However, the calcofluor white signals from β-glucans was detected in plasmolyzed cells with disrupted Hechtian strands, whereas no signals were detected in untreated plasmolyzed cells. These results suggest that Hechtian strands play roles in sensing cell wall integrity.
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Affiliation(s)
- Arata Yoneda
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; (A.Y.); (M.O.); (D.K.); (Y.H.)
| | - Misato Ohtani
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; (A.Y.); (M.O.); (D.K.); (Y.H.)
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan
| | - Daisuke Katagiri
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; (A.Y.); (M.O.); (D.K.); (Y.H.)
| | - Yoichiroh Hosokawa
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; (A.Y.); (M.O.); (D.K.); (Y.H.)
| | - Taku Demura
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; (A.Y.); (M.O.); (D.K.); (Y.H.)
- Correspondence: ; Tel.: +81-743-72-5460
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Wang Y, Tyler BM, Wang Y. Defense and Counterdefense During Plant-Pathogenic Oomycete Infection. Annu Rev Microbiol 2019; 73:667-696. [DOI: 10.1146/annurev-micro-020518-120022] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Plant-pathogenic oomycetes include numerous species that are ongoing threats to agriculture and natural ecosystems. Understanding the molecular dialogs between oomycetes and plants is instrumental for sustaining effective disease control. Plants respond to oomycete infection by multiple defense actions including strengthening of physical barriers, production of antimicrobial molecules, and programmed cell death. These responses are tightly controlled and integrated via a three-layered immune system consisting of a multiplex recognition layer, a resilient signal-integration layer, and a diverse defense-action layer. Adapted oomycete pathogens utilize apoplastic and intracellular effector arsenals to counter plant immunity mechanisms within each layer, including by evasion or suppression of recognition, interference with numerous signaling components, and neutralization or suppression of defense actions. A coevolutionary arms race continually drives the emergence of new mechanisms of plant defense and oomycete counterdefense.
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Affiliation(s)
- Yan Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China;,
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Brett M. Tyler
- Center for Genome Research and Biocomputing and Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA
| | - Yuanchao Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China;,
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
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Elhasi T, Blomberg A. Integrins in disguise - mechanosensors in Saccharomyces cerevisiae as functional integrin analogues. MICROBIAL CELL 2019; 6:335-355. [PMID: 31404395 PMCID: PMC6685044 DOI: 10.15698/mic2019.08.686] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The ability to sense external mechanical stimuli is vital for all organisms. Integrins are transmembrane receptors that mediate bidirectional signalling between the extracellular matrix (ECM) and the cytoskeleton in animals. Thus, integrins can sense changes in ECM mechanics and can translate these into internal biochemical responses through different signalling pathways. In the model yeast species Saccharomyces cerevisiae there are no proteins with sequence similarity to mammalian integrins. However, we here emphasise that the WSC-type (Wsc1, Wsc2, and Wsc3) and the MID-type (Mid2 and Mtl1) mechanosensors in yeast act as partial functional integrin analogues. Various environmental cues recognised by these mechanosensors are transmitted by a conserved signal transduction cascade commonly referred to as the PKC1-SLT1 cell wall integrity (CWI) pathway. We exemplify the WSC- and MID-type mechanosensors functional analogy to integrins with a number of studies where they resemble the integrins in terms of both mechanistic and molecular features as well as in the overall phenotypic consequences of their activity. In addition, many important components in integrin-dependent signalling in humans are conserved in yeast; for example, Sla1 and Sla2 are homologous to different parts of human talin, and we propose that they together might be functionally similar to talin. We also propose that the yeast cell wall is a prominent cellular feature involved in sensing a number of external factors and subsequently activating different signalling pathways. In a hypothetical model, we propose that nutrient limitations modulate cell wall elasticity, which is sensed by the mechanosensors and results in filamentous growth. We believe that mechanosensing is a somewhat neglected aspect of yeast biology, and we argue that the physiological and molecular consequences of signal transduction initiated at the cell wall deserve more attention.
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Affiliation(s)
- Tarek Elhasi
- Dept. of Chemistry and Molecular Biology, Univ. of Gothenburg, Sweden
| | - Anders Blomberg
- Dept. of Chemistry and Molecular Biology, Univ. of Gothenburg, Sweden
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Abstract
Mechanical signals play many roles in cell and developmental biology. Several mechanotransduction pathways have been uncovered, but the mechanisms identified so far only address the perception of stress intensity. Mechanical stresses are tensorial in nature, and thus provide dual mechanical information: stress magnitude and direction. Here we propose a parsimonious mechanism for the perception of the principal stress direction. In vitro experiments show that microtubules are stabilized under tension. Based on these results, we explore the possibility that such microtubule stabilization operates in vivo, most notably in plant cells where turgor-driven tensile stresses exceed greatly those observed in animal cells. Cellular mechanical stress is a key determinant of cell shape and function, but how the cell senses stress direction is unclear. In this Perspective the authors propose that microtubules autonomously sense stress directions in plant cells, where tensile stresses are higher than in animal cells.
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Liu L, Xu L, Jia Q, Pan R, Oelmüller R, Zhang W, Wu C. Arms race: diverse effector proteins with conserved motifs. PLANT SIGNALING & BEHAVIOR 2019; 14:1557008. [PMID: 30621489 PMCID: PMC6351098 DOI: 10.1080/15592324.2018.1557008] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Effector proteins play important roles in the infection by pathogenic oomycetes and fungi or the colonization by endophytic and mycorrhizal fungi. They are either translocated into the host plant cells via specific translocation mechanisms and function in the host's cytoplasm or nucleus, or they reside in the apoplast of the plant cells and act at the extracellular host-microbe interface. Many effector proteins possess conserved motifs (such as the RXLR, CRN, LysM, RGD, DELD, EAR, RYWT, Y/F/WXC or CFEM motifs) localized in their N- or C-terminal regions. Analysis of the functions of effector proteins, especially so-called "core effectors", is crucial for the understanding of pathogenicity/symbiosis mechanisms and plant defense strategies, and helps to develop breeding strategies for pathogen-resistant cultivars, and to increase crop yield and quality as well as abiotic stress resistance. This review summarizes current knowledge about these effector proteins with the conversed motifs and their involvement in pathogenic or mutualistic plant/fungal interactions.
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Affiliation(s)
- Liping Liu
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
| | - Le Xu
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
| | - Qie Jia
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
| | - Rui Pan
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
| | - Ralf Oelmüller
- Plant Physiology, Matthias-Schleiden-Institute for Genetics, Bioinformatics and Molecular Botany, Faculty of Biological Science, Friedrich-Schiller-University Jena, Jena, Germany
| | - Wenying Zhang
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
- CONTACT Wenying Zhang Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou 434025, China; Chu Wu College of Horticulture & Gardening, Yangtze University, Jingzhou 434025, China
| | - Chu Wu
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
- Institute of Plant Ecology and Environmental Restoration, Yangtze University, Jingzhou, China
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11
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Bacete L, Mélida H, Miedes E, Molina A. Plant cell wall-mediated immunity: cell wall changes trigger disease resistance responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 93:614-636. [PMID: 29266460 DOI: 10.1111/tpj.13807] [Citation(s) in RCA: 282] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 12/07/2017] [Accepted: 12/14/2017] [Indexed: 05/18/2023]
Abstract
Plants have evolved a repertoire of monitoring systems to sense plant morphogenesis and to face environmental changes and threats caused by different attackers. These systems integrate different signals into overreaching triggering pathways which coordinate developmental and defence-associated responses. The plant cell wall, a dynamic and complex structure surrounding every plant cell, has emerged recently as an essential component of plant monitoring systems, thus expanding its function as a passive defensive barrier. Plants have a dedicated mechanism for maintaining cell wall integrity (CWI) which comprises a diverse set of plasma membrane-resident sensors and pattern recognition receptors (PRRs). The PRRs perceive plant-derived ligands, such as peptides or wall glycans, known as damage-associated molecular patterns (DAMPs). These DAMPs function as 'danger' alert signals activating DAMP-triggered immunity (DTI), which shares signalling components and responses with the immune pathways triggered by non-self microbe-associated molecular patterns that mediate disease resistance. Alteration of CWI by impairment of the expression or activity of proteins involved in cell wall biosynthesis and/or remodelling, as occurs in some plant cell wall mutants, or by wall damage due to colonization by pathogens/pests, activates specific defensive and growth responses. Our current understanding of how these alterations of CWI are perceived by the wall monitoring systems is scarce and few plant sensors/PRRs and DAMPs have been characterized. The identification of these CWI sensors and PRR-DAMP pairs will help us to understand the immune functions of the wall monitoring system, and might allow the breeding of crop varieties and the design of agricultural strategies that would enhance crop disease resistance.
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Affiliation(s)
- Laura Bacete
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo UPM, 28223, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaría y de Biosistemas, UPM, 28040, Madrid, Spain
| | - Hugo Mélida
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo UPM, 28223, Pozuelo de Alarcón, Madrid, Spain
| | - Eva Miedes
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo UPM, 28223, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaría y de Biosistemas, UPM, 28040, Madrid, Spain
| | - Antonio Molina
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo UPM, 28223, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaría y de Biosistemas, UPM, 28040, Madrid, Spain
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12
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Yu Q, Ren JJ, Kong LJ, Wang XL. Actin filaments regulate the adhesion between the plasma membrane and the cell wall of tobacco guard cells. PROTOPLASMA 2018; 255:235-245. [PMID: 28803402 DOI: 10.1007/s00709-017-1149-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 07/24/2017] [Indexed: 06/07/2023]
Abstract
During the opening and closing of stomata, guard cells undergo rapid and reversible changes in their volume and shape, which affects the adhesion of the plasma membrane (PM) to the cell wall (CW). The dynamics of actin filaments in guard cells are involved in stomatal movement by regulating structural changes and intracellular signaling. However, it is unclear whether actin dynamics regulate the adhesion of the PM to the CW. In this study, we investigated the relationship between actin dynamics and PM-CW adhesion by the hyperosmotic-induced plasmolysis of tobacco guard cells. We found that actin filaments in guard cells were depolymerized during mannitol-induced plasmolysis. The inhibition of actin dynamics by treatment with latrunculin B or jasplakinolide and the disruption of the adhesion between the PM and the CW by treatment with RGDS peptide (Arg-Gly-Asp-Ser) enhanced guard cell plasmolysis. However, treatment with latrunculin B alleviated the RGDS peptide-induced plasmolysis and endocytosis. Our results reveal that the actin depolymerization is involved in the regulation of the PW-CW adhesion during hyperosmotic-induced plasmolysis in tobacco guard cells.
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Affiliation(s)
- Qin Yu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Jing-Jing Ren
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Lan-Jing Kong
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Xiu-Ling Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China.
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13
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Wang Y, Wang Y. Trick or Treat: Microbial Pathogens Evolved Apoplastic Effectors Modulating Plant Susceptibility to Infection. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:6-12. [PMID: 29090656 DOI: 10.1094/mpmi-07-17-0177-fi] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The apoplastic space between the plant cell wall and the plasma membrane constitutes a major battleground for plant-pathogen interactions. To survive in harsh conditions in the plant apoplast, pathogens must cope with various immune responses. During infection, plant pathogens secrete an arsenal of effector proteins into the apoplast milieu, some of which are detected by the plant surveillance system and, thus, activate plant innate immunity. Effectors that evade plant perception act in modulating plant apoplast immunity to favor successful pathogen infection. The concerted actions of apoplastic effectors often determine the outcomes of plant-pathogen interactions. In this review, we summarize current advances on the understanding of apoplastic effectors and highlight the strategies employed by pathogens to counter host apoplastic defense.
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Affiliation(s)
- Yan Wang
- Department of Plant Pathology, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, 210095, China
| | - Yuanchao Wang
- Department of Plant Pathology, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, 210095, China
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14
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Sussmilch FC, McAdam SAM. Surviving a Dry Future: Abscisic Acid (ABA)-Mediated Plant Mechanisms for Conserving Water under Low Humidity. PLANTS (BASEL, SWITZERLAND) 2017; 6:E54. [PMID: 29113039 PMCID: PMC5750630 DOI: 10.3390/plants6040054] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 10/29/2017] [Accepted: 11/01/2017] [Indexed: 12/15/2022]
Abstract
Angiosperms are able to respond rapidly to the first sign of dry conditions, a decrease in air humidity, more accurately described as an increase in the vapor pressure deficit between the leaf and the atmosphere (VPD), by abscisic acid (ABA)-mediated stomatal closure. The genes underlying this response offer valuable candidates for targeted selection of crop varieties with improved drought tolerance, a critical goal for current plant breeding programs, to maximize crop production in drier and increasingly marginalized environments, and meet the demands of a growing population in the face of a changing climate. Here, we review current understanding of the genetic mechanisms underpinning ABA-mediated stomatal closure, a key means for conserving water under dry conditions, examine how these mechanisms evolved, and discuss what remains to be investigated.
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Affiliation(s)
- Frances C Sussmilch
- School of Biological Sciences, University of Tasmania, Hobart TAS 7001, Australia.
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97082 Würzburg, Germany.
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
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15
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Balagué C, Gouget A, Bouchez O, Souriac C, Haget N, Boutet‐Mercey S, Govers F, Roby D, Canut H. The Arabidopsis thaliana lectin receptor kinase LecRK-I.9 is required for full resistance to Pseudomonas syringae and affects jasmonate signalling. MOLECULAR PLANT PATHOLOGY 2017; 18:937-948. [PMID: 27399963 PMCID: PMC6638305 DOI: 10.1111/mpp.12457] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/15/2016] [Accepted: 06/22/2016] [Indexed: 05/20/2023]
Abstract
On microbial attack, plants can detect invaders and activate plant innate immunity. For the detection of pathogen molecules or cell wall damage, plants employ receptors that trigger the activation of defence responses. Cell surface proteins that belong to large families of lectin receptor kinases are candidates to function as immune receptors. Here, the function of LecRK-I.9 (At5g60300), a legume-type lectin receptor kinase involved in cell wall-plasma membrane contacts and in extracellular ATP (eATP) perception, was studied through biochemical, gene expression and reverse genetics approaches. In Arabidopsis thaliana, LecRK-I.9 expression is rapidly, highly and locally induced on inoculation with avirulent strains of Pseudomonas syringae pv. tomato (Pst). Two allelic lecrk-I.9 knock-out mutants showed decreased resistance to Pst. Conversely, over-expression of LecRK-I.9 led to increased resistance to Pst. The analysis of defence gene expression suggests an alteration of both the salicylic acid (SA) and jasmonic acid (JA) signalling pathways. In particular, LecRK-I.9 expression during plant-pathogen interaction was dependent on COI1 (CORONATINE INSENSITIVE 1) and JAR1 (JASMONATE RESISTANT 1) components, and JA-responsive transcription factors (TFs) showed altered levels of expression in plants over-expressing LecRK-I.9. A similar misregulation of these TFs was obtained by JA treatment. This study identified LecRK-I.9 as necessary for full resistance to Pst and demonstrated its involvement in the control of defence against pathogens through a regulation of JA signalling components. The role of LecRK-I.9 is discussed with regard to the potential molecular mechanisms linking JA signalling to cell wall damage and/or eATP perception.
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Affiliation(s)
- Claudine Balagué
- CNRSLaboratoire des Interactions Plantes Microorganismes (LIPM), UMR2594Castanet‐Tolosan31326France
- INRA, Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR441Castanet‐Tolosan31326France
| | - Anne Gouget
- CNRSLaboratoire des Interactions Plantes Microorganismes (LIPM), UMR2594Castanet‐Tolosan31326France
- INRA, Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR441Castanet‐Tolosan31326France
- Laboratoire de Recherche en Sciences VégétalesUniversité de Toulouse, CNRS, UPS; BP 42617 AuzevilleCastanet‐Tolosan31326France
| | - Olivier Bouchez
- CNRSLaboratoire des Interactions Plantes Microorganismes (LIPM), UMR2594Castanet‐Tolosan31326France
- INRA, Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR441Castanet‐Tolosan31326France
| | - Camille Souriac
- CNRSLaboratoire des Interactions Plantes Microorganismes (LIPM), UMR2594Castanet‐Tolosan31326France
- INRA, Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR441Castanet‐Tolosan31326France
- Laboratoire de Recherche en Sciences VégétalesUniversité de Toulouse, CNRS, UPS; BP 42617 AuzevilleCastanet‐Tolosan31326France
| | - Nathalie Haget
- Laboratoire de Recherche en Sciences VégétalesUniversité de Toulouse, CNRS, UPS; BP 42617 AuzevilleCastanet‐Tolosan31326France
| | - Stéphanie Boutet‐Mercey
- AgroParisTechInstitut Jean‐Pierre Bourgin, Unité Mixte de Recherche 1318, Saclay Plant ScienceVersailles78000France
| | - Francine Govers
- Laboratory of PhytopathologyPlant Sciences Group, Wageningen UniversityDroevendaalsesteeg 1WageningenPB6708the Netherlands
| | - Dominique Roby
- CNRSLaboratoire des Interactions Plantes Microorganismes (LIPM), UMR2594Castanet‐Tolosan31326France
- INRA, Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR441Castanet‐Tolosan31326France
| | - Hervé Canut
- Laboratoire de Recherche en Sciences VégétalesUniversité de Toulouse, CNRS, UPS; BP 42617 AuzevilleCastanet‐Tolosan31326France
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Tröster V, Setzer T, Hirth T, Pecina A, Kortekamp A, Nick P. Probing the contractile vacuole as Achilles' heel of the biotrophic grapevine pathogen Plasmopara viticola. PROTOPLASMA 2017; 254:1887-1901. [PMID: 28550468 DOI: 10.1007/s00709-017-1123-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/10/2017] [Indexed: 05/20/2023]
Abstract
The causative agent of Grapevine Downy Mildew, the oomycete Plasmopara viticola, poses a serious threat to viticulture. In the current work, the contractile vacuole of the zoospore is analysed as potential target for novel plant protection strategies. Using a combination of electron microscopy, spinning disc confocal microscopy, and video differential interference contrast microscopy, we have followed the genesis and dynamics of this vacuole required during the search for the stomata, when the non-walled zoospore is exposed to hypotonic conditions. This subcellular description was combined with a pharmacological study, where the functionality of the contractile vacuole was blocked by manipulation of actin, by Na, Cu, and Al ions or by inhibition of the NADPH oxidase. We further observe that RGD peptides (mimicking binding sites for integrins at the extracellular matrix) can inhibit the function of the contractile vacuole as well. Finally, we show that an extract from Chinese liquorice (Glycyrrhiza uralensis) proposed as biocontrol for Downy Mildews can efficiently induce zoospore burst and that this activity depends on the activity of NADPH oxidase. The effect of the extract can be phenocopied by its major compound, glycyrrhizin, suggesting a mode of action for this biologically safe alternative to copper products.
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Affiliation(s)
- Viktoria Tröster
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Tabea Setzer
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Thomas Hirth
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Anna Pecina
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Andreas Kortekamp
- Institute of Plant Protection State Education and Research Center (DLR) Rheinpfalz, Breitenweg 71, 67435, Neustadt, Germany
| | - Peter Nick
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany.
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17
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Plant Lectins and Lectin Receptor-Like Kinases: How Do They Sense the Outside? Int J Mol Sci 2017; 18:ijms18061164. [PMID: 28561754 PMCID: PMC5485988 DOI: 10.3390/ijms18061164] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 05/26/2017] [Accepted: 05/28/2017] [Indexed: 11/17/2022] Open
Abstract
Lectins are fundamental to plant life and have important roles in cell-to-cell communication; development and defence strategies. At the cell surface; lectins are present both as soluble proteins (LecPs) and as chimeric proteins: lectins are then the extracellular domains of receptor-like kinases (LecRLKs) and receptor-like proteins (LecRLPs). In this review; we first describe the domain architectures of proteins harbouring G-type; L-type; LysM and malectin carbohydrate-binding domains. We then focus on the functions of LecPs; LecRLKs and LecRLPs referring to the biological processes they are involved in and to the ligands they recognize. Together; LecPs; LecRLKs and LecRLPs constitute versatile recognition systems at the cell surface contributing to the detection of symbionts and pathogens; and/or involved in monitoring of the cell wall structure and cell growth.
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18
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Langhans M, Weber W, Babel L, Grunewald M, Meckel T. The right motifs for plant cell adhesion: what makes an adhesive site? PROTOPLASMA 2017; 254:95-108. [PMID: 27091341 DOI: 10.1007/s00709-016-0970-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 03/31/2016] [Indexed: 06/05/2023]
Abstract
Cells of multicellular organisms are surrounded by and attached to a matrix of fibrous polysaccharides and proteins known as the extracellular matrix. This fibrous network not only serves as a structural support to cells and tissues but also plays an integral part in the process as important as proliferation, differentiation, or defense. While at first sight, the extracellular matrices of plant and animals do not have much in common, a closer look reveals remarkable similarities. In particular, the proteins involved in the adhesion of the cell to the extracellular matrix share many functional properties. At the sequence level, however, a surprising lack of homology is found between adhesion-related proteins of plants and animals. Both protein machineries only reveal similarities between small subdomains and motifs, which further underlines their functional relationship. In this review, we provide an overview on the similarities between motifs in proteins known to be located at the plant cell wall-plasma membrane-cytoskeleton interface to proteins of the animal adhesome. We also show that by comparing the proteome of both adhesion machineries at the level of motifs, we are also able to identify potentially new candidate proteins that functionally contribute to the adhesion of the plant plasma membrane to the cell wall.
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Affiliation(s)
- Markus Langhans
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Germany, Schnittspahnstrasse 3, 64297, Darmstadt, Germany
| | - Wadim Weber
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Germany, Schnittspahnstrasse 3, 64297, Darmstadt, Germany
| | - Laura Babel
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Germany, Schnittspahnstrasse 3, 64297, Darmstadt, Germany
| | - Miriam Grunewald
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Germany, Schnittspahnstrasse 3, 64297, Darmstadt, Germany
| | - Tobias Meckel
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Germany, Schnittspahnstrasse 3, 64297, Darmstadt, Germany.
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Yaaran A, Moshelion M. Role of Aquaporins in a Composite Model of Water Transport in the Leaf. Int J Mol Sci 2016; 17:E1045. [PMID: 27376277 PMCID: PMC4964421 DOI: 10.3390/ijms17071045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/22/2016] [Accepted: 06/24/2016] [Indexed: 01/02/2023] Open
Abstract
Water-transport pathways through the leaf are complex and include several checkpoints. Some of these checkpoints exhibit dynamic behavior that may be regulated by aquaporins (AQPs). To date, neither the relative weight of the different water pathways nor their molecular mechanisms are well understood. Here, we have collected evidence to support a putative composite model of water pathways in the leaf and the distribution of water across those pathways. We describe how water moves along a single transcellular path through the parenchyma and continues toward the mesophyll and stomata along transcellular, symplastic and apoplastic paths. We present evidence that points to a role for AQPs in regulating the relative weight of each path in the overall leaf water-transport system and the movement of water between these paths as a result of the integration of multiple signals, including transpiration demand, water potential and turgor. We also present a new theory, the hydraulic fuse theory, to explain effects of the leaf turgor-loss-point on water paths alternation and the subsequent reduction in leaf hydraulic conductivity. An improved understating of leaf water-balance management may lead to the development of crops that use water more efficiently, and responds better to environmental changes.
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Affiliation(s)
- Adi Yaaran
- Faculty of Agriculture, Food and Environment, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
| | - Menachem Moshelion
- Faculty of Agriculture, Food and Environment, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
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20
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Beracochea VC, Almasia NI, Peluffo L, Nahirñak V, Hopp EH, Paniego N, Heinz RA, Vazquez-Rovere C, Lia VV. Sunflower germin-like protein HaGLP1 promotes ROS accumulation and enhances protection against fungal pathogens in transgenic Arabidopsis thaliana. PLANT CELL REPORTS 2015; 34:1717-33. [PMID: 26070410 DOI: 10.1007/s00299-015-1819-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 05/20/2015] [Accepted: 06/02/2015] [Indexed: 05/21/2023]
Abstract
The novel sunflower gene HaGLP1 is the first germin-like protein characterized from the family Asteraceae. It alters the host redox status and confers protection against Sclerotinia sclerotiorum and Rhizoctonia solani. Germin-like proteins (GLPs) are a large, diverse and ubiquitous family of plant glycoproteins belonging to the Cupin super family. These proteins have been widely studied because of their diverse roles in important plant processes, including defence. The novel sunflower gene HaGLP1 encodes the first germin-like protein characterized from the family Asteraceae. To analyse whether constitutive in vivo expression of the HaGLP1 gene may lead to disease tolerance, we developed transgenic Arabidopsis plants that were molecularly characterized and biologically assessed after inoculation with Sclerotinia sclerotiorum or Rhizoctonia solani. HaGLP1 expression in Arabidopsis plants conferred tolerance to S. sclerotiorum at the first stages of disease and interfered with R. solani infection, thus giving rise to significant protection against the latter. Furthermore, HaGLP1 expression in Arabidopsis plants elevated endogenous ROS levels. HaGLP1-induced tolerance does not appear to be related to a constitutive induction of the plant defence or the ROS-related genes examined here. In conclusion, our data suggest that HaGLP1 is an interesting candidate for the engineering of plants with increased fungal tolerance and that this gene could also be useful for the selection of naturally overexpressing sunflower genotypes for conventional breeding purposes.
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Affiliation(s)
- V C Beracochea
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
| | - N I Almasia
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
| | - L Peluffo
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
| | - V Nahirñak
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
| | - E H Hopp
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (EHA1428), Buenos Aires, Argentina
| | - N Paniego
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma De Buenos Aires, Buenos Aires, Argentina
| | - R A Heinz
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (EHA1428), Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma De Buenos Aires, Buenos Aires, Argentina
| | - C Vazquez-Rovere
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma De Buenos Aires, Buenos Aires, Argentina
| | - V V Lia
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA)-Castelar, Dr. Nicolás Repetto y De Los Reseros S/Nº (B1686IGC) Hurlingham, Buenos Aires, Provincia De Buenos Aires, Argentina.
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (EHA1428), Buenos Aires, Argentina.
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma De Buenos Aires, Buenos Aires, Argentina.
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Haswell ES, Verslues PE. The ongoing search for the molecular basis of plant osmosensing. ACTA ACUST UNITED AC 2015; 145:389-94. [PMID: 25870206 PMCID: PMC4411250 DOI: 10.1085/jgp.201411295] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Elizabeth S Haswell
- Department of Biology, Washington University in Saint Louis, Saint Louis, MO 63130
| | - Paul E Verslues
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
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22
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Liu Z, Persson S, Zhang Y. The connection of cytoskeletal network with plasma membrane and the cell wall. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2015; 57:330-40. [PMID: 25693826 PMCID: PMC4405036 DOI: 10.1111/jipb.12342] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/14/2015] [Indexed: 05/18/2023]
Abstract
The cell wall provides external support of the plant cells, while the cytoskeletons including the microtubules and the actin filaments constitute an internal framework. The cytoskeletons contribute to the cell wall biosynthesis by spatially and temporarily regulating the transportation and deposition of cell wall components. This tight control is achieved by the dynamic behavior of the cytoskeletons, but also through the tethering of these structures to the plasma membrane. This tethering may also extend beyond the plasma membrane and impact on the cell wall, possibly in the form of a feedback loop. In this review, we discuss the linking components between the cytoskeletons and the plasma membrane, and/or the cell wall. We also discuss the prospective roles of these components in cell wall biosynthesis and modifications, and aim to provide a platform for further studies in this field.
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Affiliation(s)
- Zengyu Liu
- Max-Planck Institute for Molecular Plant Physiology14476 Potsdam, Germany
| | - Staffan Persson
- Max-Planck Institute for Molecular Plant Physiology14476 Potsdam, Germany
- ARC Centre of Excellence in Plant Cell Walls, School of Botany, University of MelbourneParkville, 3010, Victoria, Australia
| | - Yi Zhang
- Max-Planck Institute for Molecular Plant Physiology14476 Potsdam, Germany
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23
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Liu Z, Persson S, Sánchez-Rodríguez C. At the border: the plasma membrane-cell wall continuum. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1553-63. [PMID: 25697794 DOI: 10.1093/jxb/erv019] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plant cells rely on their cell walls for directed growth and environmental adaptation. Synthesis and remodelling of the cell walls are membrane-related processes. During cell growth and exposure to external stimuli, there is a constant exchange of lipids, proteins, and other cell wall components between the cytosol and the plasma membrane/apoplast. This exchange of material and the localization of cell wall proteins at certain spots in the plasma membrane seem to rely on a particular membrane composition. In addition, sensors at the plasma membrane detect changes in the cell wall architecture, and activate cytoplasmic signalling schemes and ultimately cell wall remodelling. The apoplastic polysaccharide matrix is, on the other hand, crucial for preventing proteins diffusing uncontrollably in the membrane. Therefore, the cell wall-plasma membrane link is essential for plant development and responses to external stimuli. This review focuses on the relationship between the cell wall and plasma membrane, and its importance for plant tissue organization.
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Affiliation(s)
- Zengyu Liu
- Max-Planck Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Staffan Persson
- Max-Planck Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany ARC Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Clara Sánchez-Rodríguez
- Max-Planck Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany Department of Biology, ETH Zurich, 8092 Zurich, Switzerland
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24
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Rossez Y, Holmes A, Wolfson EB, Gally DL, Mahajan A, Pedersen HL, Willats WG, Toth IK, Holden NJ. Flagella interact with ionic plant lipids to mediate adherence of pathogenicEscherichia colito fresh produce plants. Environ Microbiol 2013; 16:2181-95. [DOI: 10.1111/1462-2920.12315] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/08/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Yannick Rossez
- Cellular and Molecular Sciences; James Hutton Institute; Dundee Scotland UK
| | - Ashleigh Holmes
- Cellular and Molecular Sciences; James Hutton Institute; Dundee Scotland UK
| | - Eliza B. Wolfson
- The Roslin Institute Division of Infection and Immunity; University of Edinburgh, R(D)SVS; Edinburgh EH25 9RG UK
| | - David L. Gally
- The Roslin Institute Division of Infection and Immunity; University of Edinburgh, R(D)SVS; Edinburgh EH25 9RG UK
| | - Arvind Mahajan
- The Roslin Institute Division of Infection and Immunity; University of Edinburgh, R(D)SVS; Edinburgh EH25 9RG UK
| | | | - William G.T. Willats
- Department of Plant Biology and Biotechnology; University of Copenhagen; Denmark
| | - Ian K. Toth
- Cellular and Molecular Sciences; James Hutton Institute; Dundee Scotland UK
| | - Nicola J. Holden
- Cellular and Molecular Sciences; James Hutton Institute; Dundee Scotland UK
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25
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Zaban B, Maisch J, Nick P. Dynamic actin controls polarity induction de novo in protoplasts. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:142-59. [PMID: 23127141 DOI: 10.1111/jipb.12001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Cell polarity and axes are central for plant morphogenesis. To study how polarity and axes are induced de novo, we investigated protoplasts of tobacco Nicotiana tabacum cv. BY-2 expressing fluorescently-tagged cytoskeletal markers. We standardized the system to such a degree that we were able to generate quantitative data on the temporal patterns of regeneration stages. The synthesis of a new cell wall marks the transition to the first stage of regeneration, and proceeds after a long preparatory phase within a few minutes. During this preparatory phase, the nucleus migrates actively, and cytoplasmic strands remodel vigorously. We probed this system for the effect of anti-cytoskeletal compounds, inducible bundling of actin, RGD-peptides, and temperature. Suppression of actin dynamics at an early stage leads to aberrant tripolar cells, whereas suppression of microtubule dynamics produces aberrant sausage-like cells with asymmetric cell walls. We integrated these data into a model, where the microtubular cytoskeleton conveys positional information between the nucleus and the membrane controlling the release or activation of components required for cell wall synthesis. Cell wall formation is followed by the induction of a new cell pole requiring dynamic actin filaments, and the new cell axis is manifested as elongation growth perpendicular to the orientation of the aligned cortical microtubules.
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Affiliation(s)
- Beatrix Zaban
- Botanical Institute, Molecular Cell Biology, Karlsruhe Institute of Technology, Kaiserstr. 2, D-76128 Karlsruhe, Germany.
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26
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Wawra S, Belmonte R, Löbach L, Saraiva M, Willems A, van West P. Secretion, delivery and function of oomycete effector proteins. Curr Opin Microbiol 2012. [DOI: 10.1016/j.mib.2012.10.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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27
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Chitcholtan K, Harris E, Yu Y, Harland C, Garrill A. An investigation into plasmolysis in the oomycete Achlya bisexualis reveals that membrane–wall attachment points are sensitive to peptides containing the sequence RGD and that cell wall deposition can occur despite retraction of the protoplast. Can J Microbiol 2012; 58:1212-20. [DOI: 10.1139/w2012-099] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The structure and function of membrane–wall attachment sites in walled cells, and how these relate to animal focal adhesions, is an area that is poorly understood. In view of this, we investigated how membrane–wall attachments that form upon plasmolysis, respond to peptides that disrupt animal focal adhesions. The degree of cytoplasmic disruption during plasmolysis was also investigated. Upon hyperosmotic challenge, the protoplast in hyphae of the oomycete Achlya bisexualis typically retracted incompletely due to membrane–wall attachments. The inclusion, in the plasmolysing solution, of peptides containing the sequence RGD disrupted these attachments in a dose-dependent manner. In some hyphae, protoplast retraction stopped temporarily at attachment points — upon resumption of retraction, material was left that traced the outline of the static protoplast. Staining of this material with fluorescence brightener indicated the presence of cellulose, which suggests that wall deposition was able to occur despite plasmolysis. The F-actin cytoskeleton was disrupted during plasmolysis; peripheral F-actin staining was observed, but there was no distinct F-actin cap; staining was more diffuse; and there were fewer plaques compared with nonplasmolysed hyphae. Our data indicate that membrane–wall attachment points are sensitive to RGD-containing peptides and that wall deposition continues despite protoplast retraction and F-actin disruption.
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Affiliation(s)
- Kenny Chitcholtan
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Elisa Harris
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - YuPing Yu
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Chad Harland
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Ashley Garrill
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
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Lü B, Wang J, Zhang Y, Wang H, Liang J, Zhang J. AT14A mediates the cell wall-plasma membrane-cytoskeleton continuum in Arabidopsis thaliana cells. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:4061-9. [PMID: 22456678 PMCID: PMC3398443 DOI: 10.1093/jxb/ers063] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 01/27/2012] [Accepted: 02/06/2012] [Indexed: 05/18/2023]
Abstract
AT14A has a small domain that has sequence similarities to integrins from animals. Integrins serve as a transmembrane linker between the extracellular matrix and the cytoskeleton, which play critical roles in a variety of biological processes. Because the function of AT14A is unknown, Arabidopsis thaliana AT14A, which is a transmembrane receptor for cell adhesion molecules and a middle member of the cell wall-plasma membrane-cytoskeleton continuum in plants, has been described. AT14A, co-expressed with green fluorescent protein (GFP), was found to localize mainly to the plasma membrane. The mutant Arabidopsis at14a-1 cells exhibit various phenotypes with cell shape, cell cluster size, thickness, and cellulose content of cell wall, the adhesion between cells, and the adhesion of plasma membrane to cell wall varied by plasmolysis. Using direct staining of filamentous actin and indirect immunofluorescence staining of microtubules, cortical actin filaments and microtubules arrays were significantly altered in cells, either where AT14A was absent or over-expressed. It is concluded that AT14A may be a substantial middle member of the cell wall-plasma membrane-cytoskeleton continuum and play an important role in the continuum by regulating cell wall and cortical cytoskeleton organization.
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Affiliation(s)
- Bing Lü
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009 People’s Republic of China
| | - Juan Wang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009 People’s Republic of China
| | - Yu Zhang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009 People’s Republic of China
| | - Hongcheng Wang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009 People’s Republic of China
| | - Jiansheng Liang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009 People’s Republic of China
| | - Jianhua Zhang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
- To whom correspondence should be addressed. E-mail:
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Underwood W. The plant cell wall: a dynamic barrier against pathogen invasion. FRONTIERS IN PLANT SCIENCE 2012; 3:85. [PMID: 22639669 PMCID: PMC3355688 DOI: 10.3389/fpls.2012.00085] [Citation(s) in RCA: 213] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 04/16/2012] [Indexed: 05/18/2023]
Abstract
Prospective plant pathogens must overcome the physical barrier presented by the plant cell wall. In addition to being a preformed, passive barrier limiting access of pathogens to plant cells, the cell wall is actively remodeled and reinforced specifically at discrete sites of interaction with potentially pathogenic microbes. Active reinforcement of the cell wall through the deposition of cell wall appositions, referred to as papillae, is an early response to perception of numerous categories of pathogens including fungi and bacteria. Rapid deposition of papillae is generally correlated with resistance to fungal pathogens that attempt to penetrate plant cell walls for the establishment of feeding structures. Despite the ubiquity and apparent importance of this early defense response, relatively little is known about the underlying molecular mechanisms and cellular processes involved in the targeting and assembly of papillae. This review summarizes recent advances in our understanding of cell wall-associated defenses induced by pathogen perception as well as the impact of changes in cell wall polymers on interactions with pathogens and highlights significant unanswered questions driving future research in the area.
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Affiliation(s)
- William Underwood
- Energy Biosciences Institute, University of CaliforniaBerkeley, CA, USA
- *Correspondence: William Underwood, Energy Biosciences Institute, University of California, 130 Calvin Lab, MC5230, Berkeley, CA 94720, USA. e-mail:
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Uma B, Rani TS, Podile AR. Warriors at the gate that never sleep: non-host resistance in plants. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:2141-52. [PMID: 22001579 DOI: 10.1016/j.jplph.2011.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 09/19/2011] [Accepted: 09/20/2011] [Indexed: 05/25/2023]
Abstract
The native resistance of most plant species against a wide variety of pathogens is known as non-host resistance (NHR), which confers durable protection to plant species. Only a few pathogens or parasites can successfully cause diseases. NHR is polygenic and appears to be linked with basal plant resistance, a form of elicited protection. Sensing of pathogens by plants is brought about through the recognition of invariant pathogen-associated molecular patterns (PAMPs) that trigger downstream defense signaling pathways. Race-specific resistance, (R)-gene mediated resistance, has been extensively studied and reviewed, while our knowledge of NHR has advanced only recently due to the improved access to excellent model systems. The continuum of the cell wall (CW) and the CW-plasma membrane (PM)-cytoskeleton plays a crucial role in perceiving external cues and activating defense signaling cascades during NHR. Based on the type of hypersensitive reaction (HR) triggered, NHR was classified into two types, namely type-I and type-II. Genetic analysis of Arabidopsis mutants has revealed important roles for a number of specific molecules in NHR, including the role of SNARE-complex mediated exocytosis, lipid rafts and vesicle trafficking. As might be expected, R-gene mediated resistance is found to overlap with NHR, but the extent to which the genes/pathways are common between these two forms of disease resistance is unknown. The present review focuses on the various components involved in the known mechanisms of NHR in plants with special reference to the role of CW-PM components.
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Affiliation(s)
- Battepati Uma
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
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Hohenberger P, Eing C, Straessner R, Durst S, Frey W, Nick P. Plant actin controls membrane permeability. BIOCHIMICA ET BIOPHYSICA ACTA 2011; 1808:2304-12. [PMID: 21669183 DOI: 10.1016/j.bbamem.2011.05.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 05/26/2011] [Accepted: 05/27/2011] [Indexed: 10/18/2022]
Abstract
The biological effects of electric pulses with low rise time, high field strength, and durations in the nanosecond range (nsPEFs) have attracted considerable biotechnological and medical interest. However, the cellular mechanisms causing membrane permeabilization by nanosecond pulsed electric fields are still far from being understood. We investigated the role of actin filaments for membrane permeability in plant cells using cell lines where different degrees of actin bundling had been introduced by genetic engineering. We demonstrate that stabilization of actin increases the stability of the plasma membrane against electric permeabilization recorded by penetration of Trypan Blue into the cytoplasm. By use of a cell line expressing the actin bundling WLIM domain under control of an inducible promotor we can activate membrane stabilization by the glucocorticoid analog dexamethasone. By total internal reflection fluorescence microscopy we can visualize a subset of the cytoskeleton that is directly adjacent to the plasma membrane. We conclude that this submembrane cytoskeleton stabilizes the plasma membrane against permeabilization through electric pulses.
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Affiliation(s)
- Petra Hohenberger
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
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Knepper C, Savory EA, Day B. The role of NDR1 in pathogen perception and plant defense signaling. PLANT SIGNALING & BEHAVIOR 2011; 6:1114-6. [PMID: 21758001 PMCID: PMC3260705 DOI: 10.4161/psb.6.8.15843] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 04/15/2011] [Indexed: 05/17/2023]
Abstract
The biochemical and cellular function of NDR1 in plant immunity and defense signaling has long remained elusive. Herein, we describe a novel role for NDR1 in both pathogen perception and plant defense signaling, elucidated by exploring a broader, physiological role for NDR1 in general stress responses and cell wall adhesion. Based on our predictive homology modeling, coupled with a structure-function approach, we found that NDR1 shares a striking similarity to mammalian integrins, well-characterized for their role in mediating the interaction between the extracellular matrix and stress signaling. ndr1-1 mutant plants exhibit higher electrolyte leakage following pathogen infection, compared to wild type Col-0. In addition, we observed an altered plasmolysis phenotype, supporting a role for NDR1 in maintaining cell wall-plasma membrane adhesions through mediating fluid loss under stress.
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Affiliation(s)
- Caleb Knepper
- Department of Energy-Plant Research Laboratory; Michigan State University; East Lansing, MI USA
- Graduate Program in Genetics; Michigan State University; East Lansing, MI USA
| | - Elizabeth A Savory
- Department of Plant Pathology; Michigan State University; East Lansing, MI USA
| | - Brad Day
- Graduate Program in Genetics; Michigan State University; East Lansing, MI USA
- Department of Plant Pathology; Michigan State University; East Lansing, MI USA
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Knepper C, Savory EA, Day B. Arabidopsis NDR1 is an integrin-like protein with a role in fluid loss and plasma membrane-cell wall adhesion. PLANT PHYSIOLOGY 2011; 156:286-300. [PMID: 21398259 PMCID: PMC3091050 DOI: 10.1104/pp.110.169656] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Accepted: 03/10/2011] [Indexed: 05/18/2023]
Abstract
Arabidopsis (Arabidopsis thaliana) NON-RACE-SPECIFIC DISEASE RESISTANCE1 (NDR1), a plasma membrane-localized protein, plays an essential role in resistance mediated by the coiled-coil-nucleotide-binding site-leucine-rich repeat class of resistance (R) proteins, which includes RESISTANCE TO PSEUDOMONAS SYRINGAE2 (RPS2), RESISTANCE TO PSEUDOMONAS SYRINGAE PV MACULICOLA1, and RPS5. Infection with Pseudomonas syringae pv tomato DC3000 expressing the bacterial effector proteins AvrRpt2, AvrB, and AvrPphB activates resistance by the aforementioned R proteins. Whereas the genetic requirement for NDR1 in plant disease resistance signaling has been detailed, our study focuses on determining a global, physiological role for NDR1. Through the use of homology modeling and structure threading, NDR1 was predicted to have a high degree of structural similarity to Arabidopsis LATE EMBRYOGENESIS ABUNDANT14, a protein implicated in abiotic stress responses. Specific protein motifs also point to a degree of homology with mammalian integrins, well-characterized proteins involved in adhesion and signaling. This structural homology led us to examine a physiological role for NDR1 in preventing fluid loss and maintaining cell integrity through plasma membrane-cell wall adhesions. Our results show a substantial alteration in induced (i.e. pathogen-inoculated) electrolyte leakage and a compromised pathogen-associated molecular pattern-triggered immune response in ndr1-1 mutant plants. As an extension of these analyses, using a combination of genetic and cell biology-based approaches, we have identified a role for NDR1 in mediating plasma membrane-cell wall adhesions. Taken together, our data point to a broad role for NDR1 both in mediating primary cellular functions in Arabidopsis through maintaining the integrity of the cell wall-plasma membrane connection and as a key signaling component of these responses during pathogen infection.
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Bouwmeester K, de Sain M, Weide R, Gouget A, Klamer S, Canut H, Govers F. The lectin receptor kinase LecRK-I.9 is a novel Phytophthora resistance component and a potential host target for a RXLR effector. PLoS Pathog 2011; 7:e1001327. [PMID: 21483488 PMCID: PMC3068997 DOI: 10.1371/journal.ppat.1001327] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 02/28/2011] [Indexed: 12/03/2022] Open
Abstract
In plants, an active defense against biotrophic pathogens is dependent on a functional continuum between the cell wall (CW) and the plasma membrane (PM). It is thus anticipated that proteins maintaining this continuum also function in defense. The legume-like lectin receptor kinase LecRK-I.9 is a putative mediator of CW-PM adhesions in Arabidopsis and is known to bind in vitro to the Phytophthora infestans RXLR-dEER effector IPI-O via a RGD cell attachment motif present in IPI-O. Here we show that LecRK-I.9 is associated with the plasma membrane, and that two T-DNA insertions lines deficient in LecRK-I.9 (lecrk-I.9) have a ‘gain-of-susceptibility’ phenotype specifically towards the oomycete Phytophthora brassicae. Accordingly, overexpression of LecRK-I.9 leads to enhanced resistance to P. brassicae. A similar ‘gain-of-susceptibility’ phenotype was observed in transgenic Arabidopsis lines expressing ipiO (35S-ipiO1). This phenocopy behavior was also observed with respect to other defense-related functions; lecrk-I.9 and 35S-ipiO1 were both disturbed in pathogen- and MAMP-triggered callose deposition. By site-directed mutagenesis, we demonstrated that the RGD cell attachment motif in IPI-O is not only essential for disrupting the CW-PM adhesions, but also for disease suppression. These results suggest that destabilizing the CW-PM continuum is one of the tactics used by Phytophthora to promote infection. As countermeasure the host may want to strengthen CW-PM adhesions and the novel Phytophthora resistance component LecRK-I.9 seems to function in this process. Phytophthora species are notorious plant pathogens which cause a variety of devastating crop diseases. Phytophthora pathogens secrete a plethora of effector proteins, several of which are known to interact with receptors in the host cell thereby either activating or suppressing defense responses. Unlike animals, plants lack an adaptive immune system; however, they are not defenseless and have acquired other mechanisms to withstand pathogens. Receptor proteins play important roles in sensing alterations at the plant cell wall and in mediating responses upon pathogen attack. This paper focuses on the Arabidopsis lectin receptor kinase LecRK-I.9, a mediator of cell wall – plasma membrane (CW-PM) adhesions that is known to bind in vitro to the Phytophthora infestans effector IPI-O via the cell attachment motif RGD. T-DNA mutants deficient in LecRK-I.9 and transgenic Arabidopsis lines expressing ipiO1 were found to behave as phenocopies. Both show a ‘gain-of-susceptibility’ phenotype towards the Arabidopsis pathogen Phytophthora brassicae and are disturbed in callose deposition. Overall, the results suggest that destabilizing the CW-PM continuum is a strategy for Phytophthora to promote infection. As countermeasure, the host may want to strengthen CW-PM adhesions, and the novel resistance component LecRK-I.9 apparently functions in this process.
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Affiliation(s)
- Klaas Bouwmeester
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
| | - Mara de Sain
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
| | - Rob Weide
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - Anne Gouget
- UMR 5546 CNRS-Université Paul Sabatier-Toulouse III, Castanet-Tolosan, France
| | - Sofieke Klamer
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - Herve Canut
- UMR 5546 CNRS-Université Paul Sabatier-Toulouse III, Castanet-Tolosan, France
| | - Francine Govers
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
- * E-mail:
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36
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Bouwmeester K, Meijer HJG, Govers F. At the Frontier; RXLR Effectors Crossing the Phytophthora-Host Interface. FRONTIERS IN PLANT SCIENCE 2011; 2:75. [PMID: 22645549 PMCID: PMC3355728 DOI: 10.3389/fpls.2011.00075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 10/17/2011] [Indexed: 05/20/2023]
Abstract
Plants are constantly beset by pathogenic organisms. To successfully infect their hosts, plant pathogens secrete effector proteins, many of which are translocated to the inside of the host cell where they manipulate normal physiological processes and undermine host defense. The way by which effectors cross the frontier to reach the inside of the host cell varies among different classes of pathogens. For oomycete plant pathogens - like the potato late blight pathogen Phytophthora infestans - it has been shown that effector translocation to the host cell cytoplasm is dependent on conserved amino acid motifs that are present in the N-terminal part of effector proteins. One of these motifs, known as the RXLR motif, has a strong resemblance with a host translocation motif found in effectors secreted by Plasmodium species. These malaria parasites, that reside inside specialized vacuoles in red blood cells, make use of a specific protein translocation complex to export effectors from the vacuole into the red blood cell. Whether or not also oomycete RXLR effectors require a translocation complex to cross the frontier is still under investigation. For one P. infestans RXLR effector named IPI-O we have found a potential host target that could play a role in establishing the first contact between this effector and the host cell. This membrane spanning lectin receptor kinase, LecRK-I.9, interacts with IPI-O via the tripeptide RGD that overlaps with the RXLR motif. In animals, RGD is a well-known cell adhesion motif; it binds to integrins, which are membrane receptors that regulate many cellular processes and which can be hijacked by pathogens for either effector translocation or pathogen entry into host cells.
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Affiliation(s)
- Klaas Bouwmeester
- Laboratory of Phytopathology, Wageningen UniversityWageningen, Netherlands
- Centre for BioSystems GenomicsWageningen, Netherlands
| | | | - Francine Govers
- Laboratory of Phytopathology, Wageningen UniversityWageningen, Netherlands
- Centre for BioSystems GenomicsWageningen, Netherlands
- *Correspondence: Francine Govers, Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, Netherlands. e-mail:
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Horbach R, Navarro-Quesada AR, Knogge W, Deising HB. When and how to kill a plant cell: infection strategies of plant pathogenic fungi. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:51-62. [PMID: 20674079 DOI: 10.1016/j.jplph.2010.06.014] [Citation(s) in RCA: 203] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 06/16/2010] [Accepted: 06/18/2010] [Indexed: 05/23/2023]
Abstract
Fungi cause severe diseases on a broad range of crop and ornamental plants, leading to significant economical losses. Plant pathogenic fungi exhibit a huge variability in their mode of infection, differentiation and function of infection structures and nutritional strategy. In this review, advances in understanding mechanisms of biotrophy, necrotrophy and hemibiotrophic lifestyles are described. Special emphasis is given to the biotrophy-necrotrophy switch of hemibiotrophic pathogens, and to biosynthesis, chemical diversity and mode of action of various fungal toxins produced during the infection process.
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Affiliation(s)
- Ralf Horbach
- Martin-Luther-University Halle-Wittenberg, Faculty of Natural Sciences III, Institute for Agricultural and Nutritional Sciences, Phytopathology and Plant Protection, Betty-Heimann-Strasse 3, Halle (Saale), Germany
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Mhedbi-Hajri N, Jacques MA, Koebnik R. Adhesion mechanisms of plant-pathogenic Xanthomonadaceae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 715:71-89. [PMID: 21557058 DOI: 10.1007/978-94-007-0940-9_5] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The family Xanthomonadaceae is a wide-spread family of bacteria belonging to the gamma subdivision of the Gram-negative proteobacteria, including the two plant-pathogenic genera Xanthomonas and Xylella, and the related genus Stenotrophomonas. Adhesion is a widely conserved virulence mechanism among Gram-negative bacteria, no matter whether they are human, animal or plant pathogens, since attachment to the host tissue is one of the key early steps of the bacterial infection process. Bacterial attachment to surfaces is mediated by surface structures that are anchored in the bacterial outer membrane and cover a broad group of fimbrial and non-fimbrial structures, commonly known as adhesins. In this chapter, we discuss recent findings on candidate adhesins of plant-pathogenic Xanthomonadaceae, including polysaccharidic (lipopolysaccharides, exopolysaccharides) and proteineous structures (chaperone/usher pili, type IV pili, autotransporters, two-partner-secreted and other outer membrane adhesins), their involvement in the formation of biofilms and their mode of regulation via quorum sensing. We then compare the arsenals of adhesins among different Xanthomonas strains and evaluate their mode of selection. Finally, we summarize the sparse knowledge on specific adhesin receptors in plants and the possible role of RGD motifs in binding to integrin-like plant molecules.
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Affiliation(s)
- Nadia Mhedbi-Hajri
- Pathologie Végétale (UMR077 INRA-Agrocampus Ouest-Université d'Angers), Beaucouzé, France.
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39
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Niehl A, Heinlein M. Cellular pathways for viral transport through plasmodesmata. PROTOPLASMA 2011; 248:75-99. [PMID: 21125301 DOI: 10.1007/s00709-010-0246-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Accepted: 11/16/2010] [Indexed: 05/03/2023]
Abstract
Plant viruses use plasmodesmata (PD) to spread infection between cells and systemically. Dependent on viral species, movement through PD can occur in virion or non-virion form, and requires different mechanisms for targeting and modification of the pore. These mechanisms are supported by viral movement proteins and by other virus-encoded factors that interact among themselves and with plant cellular components to facilitate virus movement in a coordinated and regulated fashion.
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Affiliation(s)
- Annette Niehl
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg, France
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40
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Ringli C. Monitoring the outside: cell wall-sensing mechanisms. PLANT PHYSIOLOGY 2010; 153:1445-52. [PMID: 20508141 PMCID: PMC2923904 DOI: 10.1104/pp.110.154518] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Accepted: 05/23/2010] [Indexed: 05/18/2023]
Affiliation(s)
- Christoph Ringli
- Institute of Plant Biology, University of Zurich, 8008 Zurich, Switzerland.
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41
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Volgger M, Lang I, Ovecka M, Lichtscheidl I. Plasmolysis and cell wall deposition in wheat root hairs under osmotic stress. PROTOPLASMA 2010; 243:51-62. [PMID: 19533299 DOI: 10.1007/s00709-009-0055-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Accepted: 05/25/2009] [Indexed: 05/27/2023]
Abstract
We analysed cell wall formation in rapidly growing root hairs of Triticum aestivum under reduced turgor pressure by application of iso- and hypertonic mannitol solutions. Our experimental series revealed an osmotic value of wheat root hairs of 150 mOsm. In higher concentrations (200-650 mOsm), exocytosis of wall material and its deposition, as well as callose synthesis, still occurred, but the elongation of root hairs was stopped. Even after strong plasmolysis when the protoplast retreated from the cell wall, deposits of wall components were observed. Labelling with DiOC(6)(3) and FM1-43 revealed numerous Hechtian strands that spanned the plasmolytic space. Interestingly, the Hechtian strands also led towards the very tip of the root hair suggesting strong anchoring sites that are readily incorporated into the new cell wall. Long-term treatments of over 24 h in mannitol solutions (150-450 mOsm) resulted in reduced growth and concentration-dependent shortening of root hairs. However, the formation of new root hairs does occur in all concentrations used. This reflects the extraordinary potential of wheat root cells to adapt to environmental stress situations.
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Affiliation(s)
- Michael Volgger
- Cell Imaging and Ultrastructure Research, Faculty of Life Sciences, The University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
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Seifert GJ, Blaukopf C. Irritable walls: the plant extracellular matrix and signaling. PLANT PHYSIOLOGY 2010; 153:467-78. [PMID: 20154095 PMCID: PMC2879813 DOI: 10.1104/pp.110.153940] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 02/10/2010] [Indexed: 05/18/2023]
Affiliation(s)
- Georg J. Seifert
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Applied Life Sciences, 1190 Vienna, Austria
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Abstract
Morphogenesis in living organisms relies on the integration of both biochemical and mechanical signals. During the last decade, attention has been mainly focused on the role of biochemical signals in patterning and morphogenesis, leaving the contribution of mechanics largely unexplored. Fortunately, the development of new tools and approaches has made it possible to re-examine these processes. In plants, shape is defined by two local variables: growth rate and growth direction. At the level of the cell, these variables depend on both the cell wall and turgor pressure. Multidisciplinary approaches have been used to understand how these cellular processes are integrated in the growing tissues. These include quantitative live imaging to measure growth rate and direction in tissues with cellular resolution. In parallel, stress patterns have been artificially modified and their impact on strain and cell behavior been analysed. Importantly, computational models based on analogies with continuum mechanics systems have been useful in interpreting the results. In this review, we will discuss these issues focusing on the shoot apical meristem, a population of stem cells that is responsible for the initiation of the aerial organs of the plant.
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Affiliation(s)
- Olivier Hamant
- Laboratoire de Reproduction et Développement des Plantes, INRA, CNRS, ENS, Université de Lyon, Lyon Cedex 07, France.
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Berghöfer T, Eing C, Flickinger B, Hohenberger P, Wegner LH, Frey W, Nick P. Nanosecond electric pulses trigger actin responses in plant cells. Biochem Biophys Res Commun 2009; 387:590-5. [PMID: 19619510 DOI: 10.1016/j.bbrc.2009.07.072] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 07/14/2009] [Indexed: 01/25/2023]
Abstract
We have analyzed the cellular effects of nanosecond pulsed electrical fields on plant cells using fluorescently tagged marker lines in the tobacco cell line BY-2 and confocal laser scanning microscopy. We observe a disintegration of the cytoskeleton in the cell cortex, followed by contraction of actin filaments towards the nucleus, and disintegration of the nuclear envelope. These responses are accompanied by irreversible permeabilization of the plasma membrane manifest as uptake of Trypan Blue. By pretreatment with the actin-stabilizing drug phalloidin, the detachment of transvacuolar actin from the cell periphery can be suppressed, and this treatment can also suppress the irreversible perforation of the plasma membrane. We discuss these findings in terms of a model, where nanosecond pulsed electric fields trigger actin responses that are key events in the plant-specific form of programmed cell death.
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Affiliation(s)
- Thomas Berghöfer
- Institute for Pulsed Power and Microwave Technology (IHM), Forschungszentrum Karlsruhe GmbH, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
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Feeling green: mechanosensing in plants. Trends Cell Biol 2009; 19:228-35. [DOI: 10.1016/j.tcb.2009.02.005] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 02/16/2009] [Accepted: 02/20/2009] [Indexed: 11/18/2022]
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Rodakowska E, Derba-Maceluch M, Kasprowicz A, Zawadzki P, Szuba A, Kierzkowski D, Wojtaszek P. Signaling and Cell Walls. SIGNALING IN PLANTS 2009. [DOI: 10.1007/978-3-540-89228-1_9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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47
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Pickard BG. "Second extrinsic organizational mechanism" for orienting cellulose: modeling a role for the plasmalemmal reticulum. PROTOPLASMA 2008; 233:7-29. [PMID: 18648731 DOI: 10.1007/s00709-008-0301-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Accepted: 12/13/2007] [Indexed: 05/26/2023]
Abstract
Oriented deposition of cellulose fibers by cellulose-synthesizing complexes typically occurs across the plasma membrane from microtubule bundles and is guided by them. However, aligned movement of the complexes can be shown even after applied oryzalin has depolymerized microtubules. Further, there is a claim that when (1) microtubules are depolymerized with oryzalin, (2) a microtubule-orienting stimulus is applied temporarily, and (3) oryzalin is washed out, the newly forming cellulose fibers are oriented with respect to the stimulus. With this in mind, the present paper gathers evidence from a diverse literature to suggest that the plasmalemmal reticulum, a major and structurally important form of cytoskeleton which connects cortical cytoplasm with wall, is a candidate to both independently and cooperatively participate in orienting microtubules and routing movements of cellulose-synthesizing complexes. Critical to this proposed function, the adhesion sites of the plasmalemmal reticulum have some morphological and molecular similarities to animal cell adhesion sites, known to play numerous integrative roles. The reticulum itself may be the morphological manifestation of the so-called lipid raft, previously known only on the basis of biochemical properties. According to the working model, the trusses interconnecting the adhesion sites shape the reticulum into apparently situation-dependent geometries. For example, in nongrowing or nonpolarized cells in which cellulose is deposited in brushy meshes, they form a nonpolar or weakly polar net; however, in elongating cells with oblique or otherwise polarized microtubules and newly forming cellulose fibers, there is suggestive evidence that net formation is dominated by trusses organized with correspondingly biased orientation. Consideration of such geometries and roles of the reticulum suggests several tests that could affirm, deny, or replace key aspects of this proposal to expand the theory of the peripheral cytoskeleton.
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Affiliation(s)
- Barbara G Pickard
- Gladys Levis Allen Laboratory of Plant Sensory Physiology, Biology Department, Washington University, 1 Brookings Drive, St. Louis, MO 63130, USA.
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Homann U, Meckel T, Hewing J, Hütt MT, Hurst AC. Distinct fluorescent pattern of KAT1::GFP in the plasma membrane of Vicia faba guard cells. Eur J Cell Biol 2007; 86:489-500. [PMID: 17602785 DOI: 10.1016/j.ejcb.2007.05.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 05/15/2007] [Accepted: 05/15/2007] [Indexed: 11/19/2022] Open
Abstract
The organisation of membrane proteins into certain domains of the plasma membrane (PM) has been proposed to be important for signalling in yeast and animal cells. Here we describe the formation of a very distinct pattern of the K(+) channel KAT1 fused to the green fluorescent protein (KAT1::GFP) when transiently expressed in guard cells of Vicia faba. Using confocal laser scanning microscopy we observed a radially striped pattern of KAT1::GFP fluorescence in the PM in about 70% of all transfected guard cells. This characteristic pattern was found to be cell type and protein specific and independent of the stomatal aperture and the cytoskeleton. Staining of the cell wall of guard cells with Calcofluor White revealed a great similarity between the arrangement of cellulose microfibrils and the KAT1::GFP pattern. Furthermore, the radial pattern of KAT1::GFP immediately disappeared when turgor pressure was strongly decreased by changing from hypotonic to hypertonic conditions. The pattern reappeared within 15 min upon reestablishment of high turgor pressure in hypotonic solution. Evaluation of the staining pattern by a mathematical algorithm further confirmed this reversible abolishment of the radial pattern during hypertonic treatment. We therefore conclude that the radial organisation of KAT1::GFP depends on the close contact between the PM and cell wall in turgid guard cells. These results offer the first indication for a role of the cell wall in the localisation of ion channels. We propose a model in which KAT1 is located in the cellulose fibrils intermediate areas of the PM and discuss the physiological role of this phenomenon.
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Affiliation(s)
- Ulrike Homann
- Institute of Botany, University of Technology Darmstadt, Schnittspahnstrasse 3-5, 64287 Darmstadt, Germany
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Mura A, Pintus F, Medda R, Floris G, Rinaldi AC, Padiglia A. Catalase and antiquitin from Euphorbia characias: Two proteins involved in plant defense? BIOCHEMISTRY (MOSCOW) 2007; 72:501-8. [PMID: 17573704 DOI: 10.1134/s0006297907050069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Here we report the cDNA nucleotide sequences of a calmodulin-binding catalase and an antiquitin from the latex of the Mediterranean shrub Euphorbia characias. Present findings suggest that catalase and antiquitin might represent additional nodes in the Euphorbia defense systems, and a multi-enzymatic interaction contributing to plant's protection against biotic and abiotic stresses is proposed to occur in E. characias laticifers.
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Affiliation(s)
- A Mura
- Department of Applied Sciences in Biosystems, University of Cagliari, Monserrato (Cagliari), I-09042, Italy
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Gao H, Gong YW, Yuan YJ. RGD-dependent mechanotransduction of suspension cultured Taxus cell in response to shear stress. Biotechnol Prog 2007; 23:673-9. [PMID: 17429942 DOI: 10.1021/bp060329+] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Plant cells cultured in bioreactors are strongly influenced by mechanical forces. However, the molecular mechanism of plant cell mechanoreception has maintained unclear. In animal cells, the Arg-Gly-Asp (RGD) motif can be found in proteins of the extracellular matrix. Integrins link the intracellular cytoskeleton of cells with the extracellular matrix by recognizing this RGD motif. Integrin has been demonstrated to function as an apparatus not only for adhesion but also for mechanotransduction. In plant cells, the molecules that mediate the structural continuity between wall and membrane are unknown. Here, we found that synthetic RGD peptide could dramatically reduce the level of phosphorylation of MAPK-like cascades that are activated by shear stress and reduce the alkalinization response, production of reactive oxygen species (ROS) and accumulation of phenolics by Taxus cuspidata cells during shear stress. These results implicate that a RGD recognition system may exist in Taxus cells and play an important role in signal transduction of shear stress. Although the Arabidopsis genome database shows that the plant seems to lack a homologue of animal integrin, plant cells may use other RGD-binding proteins to recognize the RGD motif. The correlative mechanism is discussed.
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Affiliation(s)
- Hong Gao
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China
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