1
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Saeed B, Deligne F, Brillada C, Dünser K, Ditengou FA, Turek I, Allahham A, Grujic N, Dagdas Y, Ott T, Kleine-Vehn J, Vert G, Trujillo M. K63-linked ubiquitin chains are a global signal for endocytosis and contribute to selective autophagy in plants. Curr Biol 2023; 33:1337-1345.e5. [PMID: 36863341 DOI: 10.1016/j.cub.2023.02.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/08/2022] [Accepted: 02/07/2023] [Indexed: 03/04/2023]
Abstract
In contrast to other eukaryotic model organisms, the closely related ubiquitin (Ub)-conjugating enzymes UBC35 and UBC36 are the main sources of K63-linked Ub chains in Arabidopsis.1 Although K63-linked chains have been associated with the regulation of vesicle trafficking, definitive proof for their role in endocytosis was missing. We show that the ubc35 ubc36 mutant has pleiotropic phenotypes related to hormone and immune signaling. Specifically, we reveal that ubc35-1 ubc36-1 plants have altered turnover of integral membrane proteins including FLS2, BRI1, and PIN1 at the plasma membrane. Our data indicates that K63-Ub chains are generally required for endocytic trafficking in plants. In addition, we show that in plants K63-Ub chains are involved in selective autophagy through NBR1, the second major pathway delivering cargoes to the vacuole for degradation. Similar to autophagy-defective mutants, ubc35-1 ubc36-1 plants display an accumulation of autophagy markers. Moreover, autophagy receptor NBR1 interacts with K63-Ub chains, which are required for its delivery to the lytic vacuole.2 Together, we show that K63-Ub chains act as a general signal required for the two main pathways delivering cargo to the vacuole and thus, to maintain proteostasis.
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Affiliation(s)
- Bushra Saeed
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Florian Deligne
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/University Toulouse 3, 31320 Auzeville Tolosane, France
| | - Carla Brillada
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Kai Dünser
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Franck Aniset Ditengou
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany; Bio Imaging Core Light Microscopy (BiMiC), Institute for Disease Modeling and Targeted Medicine (IMITATE), Medical Center University of Freiburg, Albert Ludwigs University Freiburg, Breisacher Str. 113, 79106 Freiburg, Germany
| | - Ilona Turek
- Department of Rural Clinical Sciences, La Trobe Rural Health School, La Trobe University, Bendigo, VIC 3552, Australia
| | - Alaa Allahham
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Nenad Grujic
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna 1030, Austria
| | - Yasin Dagdas
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna 1030, Austria
| | - Thomas Ott
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany
| | - Jürgen Kleine-Vehn
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany
| | - Grégory Vert
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/University Toulouse 3, 31320 Auzeville Tolosane, France.
| | - Marco Trujillo
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany.
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2
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Dünser K, Schöller M, Rößling AK, Löfke C, Xiao N, Pařízková B, Melnik S, Rodriguez-Franco M, Stöger E, Novák O, Kleine-Vehn J. Endocytic trafficking promotes vacuolar enlargements for fast cell expansion rates in plants. eLife 2022; 11:75945. [PMID: 35686734 PMCID: PMC9187339 DOI: 10.7554/elife.75945] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 05/31/2022] [Indexed: 11/13/2022] Open
Abstract
The vacuole has a space-filling function, allowing a particularly rapid plant cell expansion with very little increase in cytosolic content (Löfke et al., 2015; Scheuring et al., 2016; Dünser et al., 2019). Despite its importance for cell size determination in plants, very little is known about the mechanisms that define vacuolar size. Here, we show that the cellular and vacuolar size expansions are coordinated. By developing a pharmacological tool, we enabled the investigation of membrane delivery to the vacuole during cellular expansion. Our data reveal that endocytic membrane sorting from the plasma membrane to the vacuole is enhanced in the course of rapid root cell expansion. While this ‘compromise’ mechanism may theoretically at first decelerate cell surface enlargements, it fuels vacuolar expansion and, thereby, ensures the coordinated augmentation of vacuolar occupancy in dynamically expanding plant cells.
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Affiliation(s)
- Kai Dünser
- Molecular Plant Physiology (MoPP), Faculty of Biology, University of Freiburg, Freiburg, Germany.,Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.,Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg, Germany
| | - Maria Schöller
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Ann-Kathrin Rößling
- Molecular Plant Physiology (MoPP), Faculty of Biology, University of Freiburg, Freiburg, Germany.,Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg, Germany
| | - Christian Löfke
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Nannan Xiao
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Barbora Pařízková
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences and Faculty of Science of Palacký University, Olomouc, Czech Republic
| | - Stanislav Melnik
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | | | - Eva Stöger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences and Faculty of Science of Palacký University, Olomouc, Czech Republic
| | - Jürgen Kleine-Vehn
- Molecular Plant Physiology (MoPP), Faculty of Biology, University of Freiburg, Freiburg, Germany.,Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.,Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg, Germany
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3
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Kang BH, Anderson CT, Arimura SI, Bayer E, Bezanilla M, Botella MA, Brandizzi F, Burch-Smith TM, Chapman KD, Dünser K, Gu Y, Jaillais Y, Kirchhoff H, Otegui MS, Rosado A, Tang Y, Kleine-Vehn J, Wang P, Zolman BK. A glossary of plant cell structures: Current insights and future questions. Plant Cell 2022; 34:10-52. [PMID: 34633455 PMCID: PMC8846186 DOI: 10.1093/plcell/koab247] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/29/2021] [Indexed: 05/03/2023]
Abstract
In this glossary of plant cell structures, we asked experts to summarize a present-day view of plant organelles and structures, including a discussion of outstanding questions. In the following short reviews, the authors discuss the complexities of the plant cell endomembrane system, exciting connections between organelles, novel insights into peroxisome structure and function, dynamics of mitochondria, and the mysteries that need to be unlocked from the plant cell wall. These discussions are focused through a lens of new microscopy techniques. Advanced imaging has uncovered unexpected shapes, dynamics, and intricate membrane formations. With a continued focus in the next decade, these imaging modalities coupled with functional studies are sure to begin to unravel mysteries of the plant cell.
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Affiliation(s)
- Byung-Ho Kang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Charles T Anderson
- Department of Biology and Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania 16802 USA
| | - Shin-ichi Arimura
- Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Emmanuelle Bayer
- Université de Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire, UMR 5200, Villenave d'Ornon F-33140, France
| | - Magdalena Bezanilla
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
| | - Miguel A Botella
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortifruticultura Subtropical y Mediterránea “La Mayora,” Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Universidad de Málaga, Málaga 29071, Spain
| | - Federica Brandizzi
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan 48824 USA
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan 48824, USA
| | - Tessa M Burch-Smith
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Kent D Chapman
- BioDiscovery Institute and Department of Biological Sciences, University of North Texas, Denton, Texas 76203, USA
| | - Kai Dünser
- Faculty of Biology, Chair of Molecular Plant Physiology (MoPP) University of Freiburg, Freiburg 79104, Germany
- Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg 79104, Germany
| | - Yangnan Gu
- Department of Plant and Microbial Biology, Innovative Genomics Institute, University of California, Berkeley, California 94720, USA
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes (RDP), Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon, France
| | - Helmut Kirchhoff
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164, USA
| | - Marisa S Otegui
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Wisconsin 53706, USA
| | - Abel Rosado
- Department of Botany, University of British Columbia, Vancouver V6T1Z4, Canada
| | - Yu Tang
- Department of Plant and Microbial Biology, Innovative Genomics Institute, University of California, Berkeley, California 94720, USA
| | - Jürgen Kleine-Vehn
- Faculty of Biology, Chair of Molecular Plant Physiology (MoPP) University of Freiburg, Freiburg 79104, Germany
- Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg 79104, Germany
| | - Pengwei Wang
- Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Bethany Karlin Zolman
- Department of Biology, University of Missouri, St. Louis, St. Louis, Missouri 63121, USA
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4
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Gronnier J, Franck CM, Stegmann M, DeFalco TA, Abarca A, von Arx M, Dünser K, Lin W, Yang Z, Kleine-Vehn J, Ringli C, Zipfel C. Regulation of immune receptor kinase plasma membrane nanoscale organization by a plant peptide hormone and its receptors. eLife 2022; 11:74162. [PMID: 34989334 PMCID: PMC8791635 DOI: 10.7554/elife.74162] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 01/05/2022] [Indexed: 01/09/2023] Open
Abstract
Spatial partitioning is a propensity of biological systems orchestrating cell activities in space and time. The dynamic regulation of plasma membrane nano-environments has recently emerged as a key fundamental aspect of plant signaling, but the molecular components governing it are still mostly unclear. The receptor kinase FERONIA (FER) controls ligand-induced complex formation of the immune receptor kinase FLAGELLIN SENSING 2 (FLS2) with its co-receptor BRASSINOSTEROID-INSENSITIVE 1-ASSOCIATED KINASE 1 (BAK1), and perception of the endogenous peptide hormone RAPID ALKALANIZATION FACTOR 23 (RALF23) by FER inhibits immunity. Here, we show that FER regulates the plasma membrane nanoscale organization of FLS2 and BAK1. Our study demonstrates that akin to FER, leucine-rich repeat (LRR) extensin proteins (LRXs) contribute to RALF23 responsiveness and regulate BAK1 nanoscale organization and immune signaling. Furthermore, RALF23 perception leads to rapid modification of FLS2 and BAK1 nanoscale organization, and its inhibitory activity on immune signaling relies on FER kinase activity. Our results suggest that perception of RALF peptides by FER and LRXs actively modulates plasma membrane nanoscale organization to regulate cell surface signaling by other ligand-binding receptor kinases.
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Affiliation(s)
- Julien Gronnier
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland.,The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Christina M Franck
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland
| | - Martin Stegmann
- The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Thomas A DeFalco
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland.,The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Alicia Abarca
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland
| | - Michelle von Arx
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Wenwei Lin
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia, Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhenbiao Yang
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia, Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Christoph Ringli
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland
| | - Cyril Zipfel
- Institute of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland.,The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
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5
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Abstract
Plant cells are surrounded by a cell wall that provides shape and physically limits cell expansion. To sense the environment and status of cell wall structures, plants have evolved cell wall integrity-sensing mechanisms that involve a number of receptors at the plasma membrane. These receptors can bind cell wall components and/or hormones to coordinate processes in the cell wall and the cytoplasm. This review focuses on the role of leucine-rich repeat extensins (LRXs) during cell wall development. LRXs are chimeric proteins that insolubilize in the cell wall and form protein-protein interaction platforms. LRXs bind RALF peptide hormones that modify cell wall expansion and also directly interact with the transmembrane receptor FERONIA, which is involved in cell growth regulation. LRX proteins, therefore, also represent a link between the cell wall and plasma membrane, perceiving extracellular signals and indirectly relaying this information to the cytoplasm.
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Affiliation(s)
- Aline Herger
- Institute of Plant and Microbial Biology, University of Zurich, Zollikerstrasse 107, 8008 Zurich, Switzerland
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Christoph Ringli
- Institute of Plant and Microbial Biology, University of Zurich, Zollikerstrasse 107, 8008 Zurich, Switzerland.
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6
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Waidmann S, Ruiz Rosquete M, Schöller M, Sarkel E, Lindner H, LaRue T, Petřík I, Dünser K, Martopawiro S, Sasidharan R, Novak O, Wabnik K, Dinneny JR, Kleine-Vehn J. Cytokinin functions as an asymmetric and anti-gravitropic signal in lateral roots. Nat Commun 2019; 10:3540. [PMID: 31387989 PMCID: PMC6684572 DOI: 10.1038/s41467-019-11483-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 07/16/2019] [Indexed: 11/09/2022] Open
Abstract
Directional organ growth allows the plant root system to strategically cover its surroundings. Intercellular auxin transport is aligned with the gravity vector in the primary root tips, facilitating downward organ bending at the lower root flank. Here we show that cytokinin signaling functions as a lateral root specific anti-gravitropic component, promoting the radial distribution of the root system. We performed a genome-wide association study and reveal that signal peptide processing of Cytokinin Oxidase 2 (CKX2) affects its enzymatic activity and, thereby, determines the degradation of cytokinins in natural Arabidopsis thaliana accessions. Cytokinin signaling interferes with growth at the upper lateral root flank and thereby prevents downward bending. Our interdisciplinary approach proposes that two phytohormonal cues at opposite organ flanks counterbalance each other's negative impact on growth, suppressing organ growth towards gravity and allow for radial expansion of the root system.
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Affiliation(s)
- Sascha Waidmann
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Michel Ruiz Rosquete
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Maria Schöller
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Elizabeth Sarkel
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Heike Lindner
- Department of Biology, Stanford University, 260 Panama Street, Stanford, CA, 94305, USA
| | - Therese LaRue
- Department of Biology, Stanford University, 260 Panama Street, Stanford, CA, 94305, USA.,Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Ivan Petřík
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University and Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Shanice Martopawiro
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, Padualaan 8, Utrecht, 3584 CH, The Netherlands
| | - Rashmi Sasidharan
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, Padualaan 8, Utrecht, 3584 CH, The Netherlands
| | - Ondrej Novak
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University and Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Krzysztof Wabnik
- Centro de Biotecnología y Genómica de Plantas (Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria), Autopista M-40, Km 38-Pozuelo de Alarcón, 28223, Madrid, Spain
| | - José R Dinneny
- Department of Biology, Stanford University, 260 Panama Street, Stanford, CA, 94305, USA.,Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria.
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7
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De Vriese K, Himschoot E, Dünser K, Nguyen L, Drozdzecki A, Costa A, Nowack MK, Kleine-Vehn J, Audenaert D, Beeckman T, Vanneste S. Identification of Novel Inhibitors of Auxin-Induced Ca 2+ Signaling via a Plant-Based Chemical Screen. Plant Physiol 2019; 180:480-496. [PMID: 30737267 PMCID: PMC6501068 DOI: 10.1104/pp.18.01393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/29/2019] [Indexed: 05/06/2023]
Abstract
Many signal perception mechanisms are connected to Ca2+-based second messenger signaling to modulate specific cellular responses. The well-characterized plant hormone auxin elicits a very rapid Ca2+ signal. However, the cellular targets of auxin-induced Ca2+ are largely unknown. Here, we screened a biologically annotated chemical library for inhibitors of auxin-induced Ca2+ entry in plant cell suspensions to better understand the molecular mechanism of auxin-induced Ca2+ and to explore the physiological relevance of Ca2+ in auxin signal transduction. Using this approach, we defined a set of diverse, small molecules that interfere with auxin-induced Ca2+ entry. Based on annotated biological activities of the hit molecules, we found that auxin-induced Ca2+ signaling is, among others, highly sensitive to disruption of membrane proton gradients and the mammalian Ca2+ channel inhibitor bepridil. Whereas protonophores nonselectively inhibited auxin-induced and osmotic stress-induced Ca2+ signals, bepridil specifically inhibited auxin-induced Ca2+ We found evidence that bepridil severely alters vacuolar morphology and antagonized auxin-induced vacuolar remodeling. Further exploration of this plant-tailored collection of inhibitors will lead to a better understanding of auxin-induced Ca2+ entry and its relevance for auxin responses.
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Affiliation(s)
- Kjell De Vriese
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Gent, Belgium
| | - Ellie Himschoot
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Gent, Belgium
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna (BOKU), 1190 Vienna, Austria
| | - Long Nguyen
- Screening Core, VIB, 9052 Gent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Andrzej Drozdzecki
- Screening Core, VIB, 9052 Gent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Alex Costa
- Department of Biosciences, University of Milan, 20133 Milan, Italy
| | - Moritz K Nowack
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Gent, Belgium
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna (BOKU), 1190 Vienna, Austria
| | - Dominique Audenaert
- Screening Core, VIB, 9052 Gent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Tom Beeckman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Gent, Belgium
| | - Steffen Vanneste
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Gent, Belgium
- Lab of Plant Growth Analysis, Ghent University Global Campus, 21985 Incheon, Republic of Korea
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8
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Dünser K, Gupta S, Herger A, Feraru MI, Ringli C, Kleine-Vehn J. Extracellular matrix sensing by FERONIA and Leucine-Rich Repeat Extensins controls vacuolar expansion during cellular elongation in Arabidopsis thaliana. EMBO J 2019; 38:e100353. [PMID: 30850388 PMCID: PMC6443208 DOI: 10.15252/embj.2018100353] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 01/10/2019] [Accepted: 01/21/2019] [Indexed: 01/23/2023] Open
Abstract
Cellular elongation requires the defined coordination of intra- and extracellular processes, but the underlying mechanisms are largely unknown. The vacuole is the biggest plant organelle, and its dimensions play a role in defining plant cell expansion rates. Here, we show that the increase in vacuolar occupancy enables cellular elongation with relatively little enlargement of the cytosol in Arabidopsis thaliana We demonstrate that cell wall properties are sensed and impact on the intracellular expansion of the vacuole. Using vacuolar morphology as a quantitative read-out for intracellular growth processes, we reveal that the underlying cell wall sensing mechanism requires interaction of extracellular leucine-rich repeat extensins (LRXs) with the receptor-like kinase FERONIA (FER). Our data suggest that LRXs link plasma membrane-localised FER with the cell wall, allowing this module to jointly sense and convey extracellular signals to the cell. This mechanism coordinates the onset of cell wall acidification and loosening with the increase in vacuolar size.
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Affiliation(s)
- Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Shibu Gupta
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Aline Herger
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Mugurel I Feraru
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Christoph Ringli
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
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9
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Dünser K, Kleine-Vehn J. Differential growth regulation in plants--the acid growth balloon theory. Curr Opin Plant Biol 2015; 28:55-9. [PMID: 26454696 DOI: 10.1016/j.pbi.2015.08.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/15/2015] [Accepted: 08/30/2015] [Indexed: 05/09/2023]
Abstract
'To grow or not to grow' is a central question in developmental biology and is nowadays tackled wonderfully by cell-biological approaches in various species. The rigid plant cell wall is a neat evolutionary invention for sessile organisms, which require form stability in the face of an ever-changing natural environment. However, this cellular packaging places special constrains on mechanisms that guide cellular growth. Considering the largely non-reversible, man-made environmental changes and our dependency on plant products, further insights into plant-specific growth regulation are highly desirable. Here we provide our personal, current view on cellular growth regulation in plants, highlighting the mutual importance of extra- and intracellular processes.
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Affiliation(s)
- Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), 1190 Vienna, Austria
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), 1190 Vienna, Austria.
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Löfke C, Scheuring D, Dünser K, Schöller M, Luschnig C, Kleine-Vehn J. Tricho- and atrichoblast cell files show distinct PIN2 auxin efflux carrier exploitations and are jointly required for defined auxin-dependent root organ growth. J Exp Bot 2015; 66:5103-12. [PMID: 26041320 PMCID: PMC4513926 DOI: 10.1093/jxb/erv282] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The phytohormone auxin is a vital growth regulator in plants. In the root epidermis auxin steers root organ growth. However, the mechanisms that allow adjacent tissues to integrate growth are largely unknown. Here, the focus is on neighbouring epidermal root tissues to assess the integration of auxin-related growth responses. The pharmacologic, genetic, and live-cell imaging approaches reveal that PIN2 auxin efflux carriers are differentially controlled in tricho- and atrichoblast cells. PIN2 proteins show lower abundance at the plasma membrane of trichoblast cells, despite showing higher rates of intracellular trafficking in these cells. The data suggest that PIN2 proteins display distinct cell-type-dependent trafficking rates to the lytic vacuole for degradation. Based on this insight, it is hypothesized that auxin-dependent processes are distinct in tricho- and atrichoblast cells. Moreover, genetic interference with epidermal patterning supports this assumption and suggests that tricho- and atrichoblasts have distinct importance for auxin-sensitive root growth and gravitropic responses.
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Affiliation(s)
- Christian Löfke
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - David Scheuring
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Maria Schöller
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Christian Luschnig
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
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Löfke C, Dünser K, Scheuring D, Kleine-Vehn J. Auxin regulates SNARE-dependent vacuolar morphology restricting cell size. eLife 2015; 4. [PMID: 25742605 PMCID: PMC4384535 DOI: 10.7554/elife.05868] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/05/2015] [Indexed: 11/13/2022] Open
Abstract
The control of cellular growth is central to multicellular patterning. In plants, the encapsulating cell wall literally binds neighbouring cells to each other and limits cellular sliding/migration. In contrast to its developmental importance, growth regulation is poorly understood in plants. Here, we reveal that the phytohormone auxin impacts on the shape of the biggest plant organelle, the vacuole. TIR1/AFBs-dependent auxin signalling posttranslationally controls the protein abundance of vacuolar SNARE components. Genetic and pharmacological interference with the auxin effect on vacuolar SNAREs interrelates with auxin-resistant vacuolar morphogenesis and cell size regulation. Vacuolar SNARE VTI11 is strictly required for auxin-reliant vacuolar morphogenesis and loss of function renders cells largely insensitive to auxin-dependent growth inhibition. Our data suggests that the adaptation of SNARE-dependent vacuolar morphogenesis allows auxin to limit cellular expansion, contributing to root organ growth rates. DOI:http://dx.doi.org/10.7554/eLife.05868.001 In plants and animals, the way that cells grow is carefully controlled to enable tissues and organs to form and be maintained. This is especially important in plants because the cells are attached to each other by their cell walls. This means that, unlike some animal cells, plant cells are not able to move around as a plant's organs develop. Plant cells contain a large storage compartment called the vacuole, which occupies 30–80% of a cell's volume. The volume of the vacuole increases as the cell increases in size, and some researchers have suggested that the vacuole might help to control cell growth. A plant hormone called auxin can alter the growth of plant cells. However, this hormone's effect depends on the position of the cell in the plant; for example, it inhibits the growth of root cells, but promotes the growth of cells in the shoots and leaves. Nevertheless, it is not clear precisely how auxin controls plant cell growth. Here, Löfke et al. studied the effect of auxin on the appearance of vacuoles in a type of plant cell—called the root epidermal cell—on the surface of the roots of a plant called Arabidopsis thaliana. The experiments show that auxin alters the appearance of the vacuoles in these cells so they become smaller in size. At the same time, auxin also inhibits the growth of these cells. Löfke et al. found that auxin increases the amount of certain proteins in the membrane that surrounds the vacuole. These proteins belong to the SNARE family and one SNARE protein in particular, called VTI11, is required for auxin to be able to both alter the appearance of the vacuoles and restrict the growth of root epidermal cells. Enzymes called PI4 kinases were also shown to be involved in the control of the SNARE proteins in response to the auxin hormone. Löfke et al.'s findings suggest that auxin restricts the growth of root epidermal cells by controlling the amount of SNARE proteins in the vacuole membrane. The next challenge will be to understand precisely how the shape of the vacuole is controlled and how it contributes to cell growth. DOI:http://dx.doi.org/10.7554/eLife.05868.002
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Affiliation(s)
- Christian Löfke
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Kai Dünser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - David Scheuring
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
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Löfke C, Dünser K, Kleine-Vehn J. Epidermal patterning genes impose non-cell autonomous cell size determination and have additional roles in root meristem size control. J Integr Plant Biol 2013; 55:864-875. [PMID: 23945284 DOI: 10.1111/jipb.12097] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 07/29/2013] [Indexed: 06/02/2023]
Abstract
The regulation of cellular growth is of vital importance for embryonic and postembryonic patterning. Growth regulation in the epidermis has importance for organ growth rates in roots and shoots, proposing epidermal cells as an interesting model for cellular growth regulation. Here we assessed whether the root epidermis is a suitable model system to address cell size determination. In Arabidopsis thaliana L., root epidermal cells are regularly spaced in neighbouring tricho- (root hair) and atrichoblast (non-hair) cells, showing already distinct cell size regulation in the root meristem. We determined cell sizes in the root meristem and at the onset of cellular elongation, revealing that not only division rates but also cellular shape is distinct in tricho- and atrichoblasts. Intriguingly, epidermal-patterning mutants, failing to define differential vacuolization in neighbouring epidermal cell files, also display non-differential growth. Using these epidermal-patterning mutants, we show that polarized growth behaviour of epidermal tricho- and atrichoblast is interdependent, suggesting non-cell autonomous signals to integrate tissue expansion. Besides the interweaved cell-type-dependent growth mechanism, we reveal an additional role for epidermal patterning genes in root meristem size and organ growth regulation. We conclude that epidermal cells represent a suitable model system to study cell size determination and interdependent tissue growth.
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Affiliation(s)
- Christian Löfke
- Department of Applied Genetics and Cell Biology, Vienna Institute of Biotechnology (VIBT), University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Vienna, Austria
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