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Lathe RS, McFarlane HE, Kesten C, Wang L, Khan GA, Ebert B, Ramírez-Rodríguez EA, Zheng S, Noord N, Frandsen K, Bhalerao RP, Persson S. NKS1/ELMO4 is an integral protein of a pectin synthesis protein complex and maintains Golgi morphology and cell adhesion in Arabidopsis. Proc Natl Acad Sci U S A 2024; 121:e2321759121. [PMID: 38579009 PMCID: PMC11009649 DOI: 10.1073/pnas.2321759121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/07/2024] [Indexed: 04/07/2024] Open
Abstract
Adjacent plant cells are connected by specialized cell wall regions, called middle lamellae, which influence critical agricultural characteristics, including fruit ripening and organ abscission. Middle lamellae are enriched in pectin polysaccharides, specifically homogalacturonan (HG). Here, we identify a plant-specific Arabidopsis DUF1068 protein, called NKS1/ELMO4, that is required for middle lamellae integrity and cell adhesion. NKS1 localizes to the Golgi apparatus and loss of NKS1 results in changes to Golgi structure and function. The nks1 mutants also display HG deficient phenotypes, including reduced seedling growth, changes to cell wall composition, and tissue integrity defects. These phenotypes are comparable to qua1 and qua2 mutants, which are defective in HG biosynthesis. Notably, genetic interactions indicate that NKS1 and the QUAs work in a common pathway. Protein interaction analyses and modeling corroborate that they work together in a stable protein complex with other pectin-related proteins. We propose that NKS1 is an integral part of a large pectin synthesis protein complex and that proper function of this complex is important to support Golgi structure and function.
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Affiliation(s)
- Rahul S. Lathe
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
- Max-Planck Institute for Molecular Plant Physiology, Potsdam14476, Germany
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, UmeåSE-90187, Sweden
| | - Heather E. McFarlane
- Department of Cell & Systems Biology, University of Toronto, Toronto, ONM5S 3G5, Canada
- School of Biosciences, University of Melbourne, Parkville, VIC3010, Australia
| | - Christopher Kesten
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
| | - Liu Wang
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
- School of Biosciences, University of Melbourne, Parkville, VIC3010, Australia
| | - Ghazanfar Abbas Khan
- School of Biosciences, University of Melbourne, Parkville, VIC3010, Australia
- Department of Animal, Plant and Soil Sciences, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, VIC3086, Australia
| | - Berit Ebert
- School of Biosciences, University of Melbourne, Parkville, VIC3010, Australia
- Department of Biology and Biotechnology, Ruhr University Bochum, Bochum44780, Germany
| | | | - Shuai Zheng
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
| | - Niels Noord
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, UmeåSE-90187, Sweden
| | - Kristian Frandsen
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
| | - Rishikesh P. Bhalerao
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, UmeåSE-90187, Sweden
| | - Staffan Persson
- Copenhagen Plant Science Center, Department of Plant & Environmental Sciences, University of Copenhagen, Frederiksberg C1871, Denmark
- Max-Planck Institute for Molecular Plant Physiology, Potsdam14476, Germany
- School of Biosciences, University of Melbourne, Parkville, VIC3010, Australia
- Joint International Research Laboratory of Metabolic & Developmental Sciences, State Key Laboratory of Hybrid Rice, University of AdelaideJoint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai200240, China
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2
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McFarlane HE. Open questions in plant cell wall synthesis. JOURNAL OF EXPERIMENTAL BOTANY 2023:erad110. [PMID: 36961357 DOI: 10.1093/jxb/erad110] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Indexed: 06/18/2023]
Abstract
Plant cells are surrounded by strong yet flexible polysaccharide-based cell walls that support the cell while also allowing growth by cell expansion. Plant cell wall research has advanced tremendously in recent years. Sequenced genomes of many model and crop plants have facilitated cataloging and characterization of many enzymes involved in cell wall synthesis. Structural information has been generated for several important cell wall synthesizing enzymes. Important tools have been developed including antibodies raised against a variety of cell wall polysaccharides and glycoproteins, collections of enzyme clones and synthetic glycan arrays for characterizing enzymes, herbicides that specifically affect cell wall synthesis, live-cell imaging probes to track cell wall synthesis, and an inducible secondary cell wall synthesis system. Despite these advances, and often because of the new information they provide, many open questions about plant cell wall polysaccharide synthesis persist. This article highlights some of the key questions that remain open, reviews the data supporting different hypotheses that address these questions, and discusses technological developments that may answer these questions in the future.
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Affiliation(s)
- Heather E McFarlane
- Department of Cell & Systems Biology, University of Toronto, 25 Harbord St., Toronto, ON, M5S 3G5, Canada
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3
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Yang B, Stamm G, Bürstenbinder K, Voiniciuc C. Microtubule-associated IQD9 orchestrates cellulose patterning in seed mucilage. THE NEW PHYTOLOGIST 2022; 235:1096-1110. [PMID: 35488480 DOI: 10.1111/nph.18188] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 04/20/2022] [Indexed: 06/14/2023]
Abstract
Arabidopsis seeds release large capsules of mucilaginous polysaccharides, which are shaped by an intricate network of cellulosic microfibrils. Cellulose synthase complexes are guided by the microtubule cytoskeleton, but it is unclear which proteins mediate this process in the seed coat epidermis. Using reverse genetics, we identified IQ67 DOMAIN 9 (IQD9) and KINESIN LIGHT CHAIN-RELATED 1 (KLCR1) as two highly expressed genes during seed development and comprehensively characterized their roles in cell wall polysaccharide biosynthesis. Mutations in IQD9 as well as in KLCR1 lead to compact mucilage capsules with aberrant cellulose distribution, which can be rescued by transgene complementation. IQD9 physically interacts with KLCR1 and localizes to cortical microtubules (MTs) to maintain their organization in seed coat epidermal (SCE) cells. IQD9 as well as a previously identified TONNEAU1 (TON1) RECRUITING MOTIF 4 (TRM4) protein act to maintain cellulose synthase velocity. Our results demonstrate that IQD9, KLCR1 and TRM4 are MT-associated proteins that are required for seed mucilage architecture. This study provides the first direct evidence that members of the IQD, KLCR and TRM families have overlapping roles in cell wall biosynthesis. Therefore, SCE cells provide an attractive system to further decipher the complex genetic regulation of polarized cellulose deposition.
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Affiliation(s)
- Bo Yang
- Independent Junior Research Group-Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle (Saale), Germany
| | - Gina Stamm
- Department of Molecular Signal Processing, Leibniz Institute of Plant Biochemistry, 06120, Halle (Saale), Germany
| | - Katharina Bürstenbinder
- Department of Molecular Signal Processing, Leibniz Institute of Plant Biochemistry, 06120, Halle (Saale), Germany
| | - Cătălin Voiniciuc
- Independent Junior Research Group-Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle (Saale), Germany
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
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4
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Sinclair R, Hsu G, Davis D, Chang M, Rosquete M, Iwasa JH, Drakakaki G. Plant cytokinesis and the construction of new cell wall. FEBS Lett 2022; 596:2243-2255. [PMID: 35695093 DOI: 10.1002/1873-3468.14426] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/10/2022]
Abstract
Cytokinesis in plants is fundamentally different from that in animals and fungi. In plant cells, a cell plate forms through the fusion of cytokinetic vesicles and then develops into the new cell wall, partitioning the cytoplasm of the dividing cell. The formation of the cell plate entails multiple stages that involve highly orchestrated vesicle accumulation, fusion, and membrane maturation, which occur concurrently with the timely deposition of polysaccharides such as callose, cellulose, and cross-linking glycans. This review summarizes the major stages in cytokinesis, endomembrane components involved in cell plate assembly and its transition to a new cell wall. An animation that can be widely used for educational purposes further summarizes the process.
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Affiliation(s)
- Rosalie Sinclair
- Department of Plant Sciences University of California Davis, Davis, CA, 95616, USA
| | - Grace Hsu
- Department of Biochemistry University of Utah, School of Medicine, Salt Lake City, UT, 84112, USA
| | - Destiny Davis
- Department of Plant Sciences University of California Davis, Davis, CA, 95616, USA.,Current address: Lawrence Berkeley National Lab, Emeryville, CA, 94608, USA
| | - Mingqin Chang
- Department of Plant Sciences University of California Davis, Davis, CA, 95616, USA
| | - Michel Rosquete
- Department of Plant Sciences University of California Davis, Davis, CA, 95616, USA.,Current address: Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Janet H Iwasa
- Department of Biochemistry University of Utah, School of Medicine, Salt Lake City, UT, 84112, USA
| | - Georgia Drakakaki
- Department of Plant Sciences University of California Davis, Davis, CA, 95616, USA
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5
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McKay DW, McFarlane HE, Qu Y, Situmorang A, Gilliham M, Wege S. Plant Trans-Golgi Network/Early Endosome pH regulation requires Cation Chloride Cotransporter (CCC1). eLife 2022; 11:70701. [PMID: 34989335 PMCID: PMC8791640 DOI: 10.7554/elife.70701] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 01/05/2022] [Indexed: 01/04/2023] Open
Abstract
Plant cells maintain a low luminal pH in the trans-Golgi-network/early endosome (TGN/EE), the organelle in which the secretory and endocytic pathways intersect. Impaired TGN/EE pH regulation translates into severe plant growth defects. The identity of the proton pump and proton/ion antiporters that regulate TGN/EE pH have been determined, but an essential component required to complete the TGN/EE membrane transport circuit remains unidentified − a pathway for cation and anion efflux. Here, we have used complementation, genetically encoded fluorescent sensors, and pharmacological treatments to demonstrate that Arabidopsis cation chloride cotransporter (CCC1) is this missing component necessary for regulating TGN/EE pH and function. Loss of CCC1 function leads to alterations in TGN/EE-mediated processes including endocytic trafficking, exocytosis, and response to abiotic stress, consistent with the multitude of phenotypic defects observed in ccc1 knockout plants. This discovery places CCC1 as a central component of plant cellular function.
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Affiliation(s)
- Daniel W McKay
- School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia
| | - Heather E McFarlane
- School of Biosciences, University of Melbourne, Melbourne, Australia.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Yue Qu
- School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia
| | - Apriadi Situmorang
- School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia
| | - Matthew Gilliham
- School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia
| | - Stefanie Wege
- School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia
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6
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McFarlane HE, Mutwil-Anderwald D, Verbančič J, Picard KL, Gookin TE, Froehlich A, Chakravorty D, Trindade LM, Alonso JM, Assmann SM, Persson S. A G protein-coupled receptor-like module regulates cellulose synthase secretion from the endomembrane system in Arabidopsis. Dev Cell 2021; 56:1484-1497.e7. [PMID: 33878345 DOI: 10.1016/j.devcel.2021.03.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 12/16/2020] [Accepted: 03/29/2021] [Indexed: 01/18/2023]
Abstract
Cellulose is produced at the plasma membrane of plant cells by cellulose synthase (CESA) complexes (CSCs). CSCs are assembled in the endomembrane system and then trafficked to the plasma membrane. Because CESAs are only active in the plasma membrane, control of CSC secretion regulates cellulose synthesis. We identified members of a family of seven transmembrane domain-containing proteins (7TMs) that are important for cellulose production during cell wall integrity stress. 7TMs are often associated with guanine nucleotide-binding (G) protein signaling and we found that mutants affecting the Gβγ dimer phenocopied the 7tm mutants. Unexpectedly, the 7TMs localized to the Golgi/trans-Golgi network where they interacted with G protein components. Here, the 7TMs and Gβγ regulated CESA trafficking but did not affect general protein secretion. Our results outline how a G protein-coupled module regulates CESA trafficking and reveal that defects in this process lead to exacerbated responses to cell wall integrity stress.
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Affiliation(s)
- Heather E McFarlane
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; Department of Cell and Systems Biology, University of Toronto, 25 Harbord St, Toronto, ON M5S 3G5, Canada.
| | - Daniela Mutwil-Anderwald
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; School of the Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Jana Verbančič
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Kelsey L Picard
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; School of Natural Sciences, University of Tasmania, Hobart 7001 TAS, Australia
| | - Timothy E Gookin
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Anja Froehlich
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - David Chakravorty
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Luisa M Trindade
- Plant Breeding, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands
| | - Jose M Alonso
- Department of Plant and Microbial Biology, Program in Genetics, North Carolina State University, Raleigh, NC 27695-7614, USA
| | - Sarah M Assmann
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Staffan Persson
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; Department of Plant & Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark; Copenhagen Plant Science Center, University of Copenhagen, 1871 Frederiksberg C, Denmark; Joint International Research Laboratory of Metabolic & Developmental Sciences, State Key Laboratory of Hybrid Rice, SJTU-University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
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7
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Kohorn BD, Dexter-Meldrum J, Zorensky FDH, Chabout S, Mouille G, Kohorn S. Pectin Dependent Cell Adhesion Restored by a Mutant Microtubule Organizing Membrane Protein. PLANTS 2021; 10:plants10040690. [PMID: 33918513 PMCID: PMC8067205 DOI: 10.3390/plants10040690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/19/2021] [Accepted: 03/30/2021] [Indexed: 11/24/2022]
Abstract
The cellulose- and pectin-rich plant cell wall defines cell structure, mediates defense against pathogens, and facilitates plant cell adhesion. An adhesion mutant screen of Arabidopsis hypocotyls identified a new allele of QUASIMODO2 (QUA2), a gene required for pectin accumulation and whose mutants have reduced pectin content and adhesion defects. A suppressor of qua2 was also isolated and describes a null allele of SABRE (SAB), which encodes a previously described plasma membrane protein required for longitudinal cellular expansion that organizes the tubulin cytoskeleton. sab mutants have increased pectin content, increased levels of expression of pectin methylesterases and extensins, and reduced cell surface area relative to qua2 and Wild Type, contributing to a restoration of cell adhesion.
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Affiliation(s)
- Bruce D. Kohorn
- Department of Biology, Bowdoin College, Brunswick, ME 04011, USA; (J.D.-M.); (F.D.H.Z.); (S.K.)
- Correspondence: ; Tel.: +1-20-7798-7068
| | - Jacob Dexter-Meldrum
- Department of Biology, Bowdoin College, Brunswick, ME 04011, USA; (J.D.-M.); (F.D.H.Z.); (S.K.)
| | - Frances D. H. Zorensky
- Department of Biology, Bowdoin College, Brunswick, ME 04011, USA; (J.D.-M.); (F.D.H.Z.); (S.K.)
| | - Salem Chabout
- IJPB, INRAE, AgroParisTech, Université Paris-Saclay, RD10, 78026 Versailles, CEDEX, France; (S.C.); (G.M.)
| | - Gregory Mouille
- IJPB, INRAE, AgroParisTech, Université Paris-Saclay, RD10, 78026 Versailles, CEDEX, France; (S.C.); (G.M.)
| | - Susan Kohorn
- Department of Biology, Bowdoin College, Brunswick, ME 04011, USA; (J.D.-M.); (F.D.H.Z.); (S.K.)
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8
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Neumann U, Hay A. Seed coat development in explosively dispersed seeds of Cardamine hirsuta. ANNALS OF BOTANY 2020; 126:39-59. [PMID: 31796954 PMCID: PMC7304473 DOI: 10.1093/aob/mcz190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/22/2019] [Indexed: 05/28/2023]
Abstract
BACKGROUND AND AIMS Seeds are dispersed by explosive coiling of the fruit valves in Cardamine hirsuta. This rapid coiling launches the small seeds on ballistic trajectories to spread over a 2 m radius around the parent plant. The seed surface interacts with both the coiling fruit valve during launch and subsequently with the air during flight. We aim to identify features of the seed surface that may contribute to these interactions by characterizing seed coat differentiation. METHODS Differentiation of the outermost seed coat layers from the outer integuments of the ovule involves dramatic cellular changes that we characterize in detail at the light and electron microscopical level including immunofluorescence and immunogold labelling. KEY RESULTS We found that the two outer integument (oi) layers of the seed coat contributed differently to the topography of the seed surface in the explosively dispersed seeds of C. hirsuta vs. the related species Arabidopsis thaliana where seed dispersal is non-explosive. The surface of A. thaliana seeds is shaped by the columella and the anticlinal cell walls of the epidermal oi2 layer. In contrast, the surface of C. hirsuta seeds is shaped by a network of prominent ridges formed by the anticlinal walls of asymmetrically thickened cells of the sub-epidermal oi1 layer, especially at the seed margin. Both the oi2 and oi1 cell layers in C. hirsuta seeds are characterized by specialized, pectin-rich cell walls that are deposited asymmetrically in the cell. CONCLUSIONS The two outermost seed coat layers in C. hirsuta have distinct properties: the sub-epidermal oi1 layer determines the topography of the seed surface, while the epidermal oi2 layer accumulates mucilage. These properties are influenced by polar deposition of distinct pectin polysaccharides in the cell wall. Although the ridged seed surface formed by oi1 cell walls is associated with ballistic dispersal in C. hirsuta, it is not restricted to explosively dispersed seeds in the Brassicaceae.
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Affiliation(s)
- Ulla Neumann
- Max Planck Institute for Plant Breeding Research, Köln, Germany
| | - Angela Hay
- Max Planck Institute for Plant Breeding Research, Köln, Germany
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9
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Feng X, Xiong J, Hu Y, Pan L, Liao Z, Zhang X, Guo W, Wu F, Xu J, Hu E, Lan H, Lu Y. Lateral mechanical impedance rather than frontal promotes cortical expansion of roots. PLANT SIGNALING & BEHAVIOR 2020; 15:1757918. [PMID: 32338134 PMCID: PMC8570719 DOI: 10.1080/15592324.2020.1757918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 03/11/2020] [Accepted: 03/12/2020] [Indexed: 06/11/2023]
Abstract
It has long been considered that mechanical impedance on root will restrict root elongation and consequently promote radial growth. When seedlings grew in sands, we did observe radial expansion of roots and it, however, arose before elongation restriction. Mechanical impedance of sands can be classified into frontal- and lateral-type based on the interaction site of root. Therefore, we suspected that radial expansion might be mainly stimulated by lateral- rather than frontal-impedance. To verify our speculation, roots were exposed to frontal- and lateral-impedance separately. Small plastic caps were used to provide pure frontal impedance on root tips and cylindrical plastic containers were used to provide pure lateral impedance. Root elongation was remarkably suppressed under the frontal impedance of plastic caps, and more than that in sand-condition. However, the radial expansion of the plastic-cap-fitted roots was far inferior to that of the sand-cultured roots. Microstructural analysis revealed that sand-condition thickened root largely dependents on cortical expansion, whereas plastic cap did it mainly by thickening stele. In cylindrical plastic containers, mechanical impedance came only from the lateral direction and promoted the expansion of cortex like sand-condition. Thus, we proposed that the expansion of cortex and the consequent radial growth of roots were mainly due to lateral impedance when seedlings grew in sands.
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Affiliation(s)
- Xuanjun Feng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Jing Xiong
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Yue Hu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Liteng Pan
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Zhengqiao Liao
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Xuemei Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Wei Guo
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Fengkai Wu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Jie Xu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Erliang Hu
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Hai Lan
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
| | - Yanli Lu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Wenjiang, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Wenjiang, Sichuan, China
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10
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Zhou R, Liu H, Ju T, Dixit R. Quantifying the polymerization dynamics of plant cortical microtubules using kymograph analysis. Methods Cell Biol 2020; 160:281-293. [PMID: 32896322 DOI: 10.1016/bs.mcb.2020.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The plant cortical microtubule array is a dynamic structure that confers cell shape and enables plants to alter their growth and development in response to internal and external cues. Cells use a variety of microtubule regulatory proteins to spatially and temporally modulate the intrinsic polymerization dynamics of cortical microtubules to arrange them into specific configurations and to reshape arrays to adapt to changing conditions. To obtain mechanistic insight into how particular microtubule regulatory proteins mediate the dynamic (re)structuring of cortical microtubule arrays, we need to measure their effect on the dynamics of cortical microtubules. In this chapter, we describe new ImageJ plugins to generate kymographs from time-lapse images and to analyze them to measure the parameters that quantitatively describe cortical microtubule dynamics.
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Affiliation(s)
- Rudy Zhou
- Department of Computer Science and Engineering, Washington University in St. Louis, St. Louis, MO, United States; Department of Biology and Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, United States
| | - Han Liu
- Department of Computer Science and Engineering, Washington University in St. Louis, St. Louis, MO, United States; Department of Biology and Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, United States
| | - Tao Ju
- Department of Computer Science and Engineering, Washington University in St. Louis, St. Louis, MO, United States.
| | - Ram Dixit
- Department of Biology and Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, United States.
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Souza MDJ, Mercadante-Simões MO, Ribeiro LM. Secondary-cell-wall release: a particular pattern of secretion in the mucilaginous seed coat of Magonia pubescens. AMERICAN JOURNAL OF BOTANY 2020; 107:31-44. [PMID: 31916253 DOI: 10.1002/ajb2.1415] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
PREMISE Plant mucilages are composed of strongly hydrophilic polysaccharides and contribute to seed germination and seedling establishment. The myxospermic seeds of Magonia pubescens, a Cerrado (neotropical savanna) tree species, produces a voluminous mucilage capsule when hydrated. The development of the mucilaginous layer, the process of mucilage secretion and its role in seed germination was not previously studied so far. METHODS Morphological, anatomical, histochemical, and ultrastructural evaluations of the seed coat during seed development were undertaken. The formation of the mucilage capsule was followed using scanning electron microscopy, and the coat's effects on seed hydration and germination were evaluated after experimental manipulation of the seed coat. RESULTS The mucilaginous layer is contained in the outer coat of the seed. The mucilage-secreting cells accumulate proteins in the outer periclinal region and acidic polysaccharides in the inner periclinal region of the periplasmic space. Neutral polysaccharides, which form the loosely organized secondary wall, form a folding, basket-like structure surrounding the acidic polysaccharides. The protoplast collapses at maturity. With hydration, the mucilage expands, breaks the epidermal layer, and forms a mucilage capsule around the seed. The mucilaginous seed coat does not increase the germination rate. CONCLUSIONS Upon mucilage hydration, the secondary cell walls forming the network of neutral polysaccharides are released, along with proteins, and help retain the acidic polysaccharides-forming a peculiar architecture that imparts integrity and consistency to the mucilage capsule. As winged seeds are not usually buried, the mucilage capsule favors seedling hydration, contributing to its establishment on the soil surface.
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Affiliation(s)
- Michely de Jesus Souza
- Laboratory of Plant Anatomy, Department of General Biology, State University of Montes Claros, 39401-089, Montes Claros, MG, Brazil
| | - Maria Olívia Mercadante-Simões
- Laboratory of Plant Anatomy, Department of General Biology, State University of Montes Claros, 39401-089, Montes Claros, MG, Brazil
| | - Leonardo Monteiro Ribeiro
- Laboratory of Micropropagation, Department of General Biology, State University of Montes Claros, 39401-089, Montes Claros, MG, Brazil
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Yang B, Voiniciuc C, Fu L, Dieluweit S, Klose H, Usadel B. TRM4 is essential for cellulose deposition in Arabidopsis seed mucilage by maintaining cortical microtubule organization and interacting with CESA3. THE NEW PHYTOLOGIST 2019; 221:881-895. [PMID: 30277578 PMCID: PMC6585848 DOI: 10.1111/nph.15442] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 08/10/2018] [Indexed: 05/07/2023]
Abstract
The differentiation of the seed coat epidermal (SCE) cells in Arabidopsis thaliana leads to the production of a large amount of pectin-rich mucilage and a thick cellulosic secondary cell wall. The mechanisms by which cortical microtubules are involved in the formation of these pectinaceous and cellulosic cell walls are still largely unknown. Using a reverse genetic approach, we found that TONNEAU1 (TON1) recruiting motif 4 (TRM4) is implicated in cortical microtubule organization in SCE cells, and functions as a novel player in the establishment of mucilage structure. TRM4 is preferentially accumulated in the SCE cells at the stage of mucilage biosynthesis. The loss of TRM4 results in compact seed mucilage capsules, aberrant mucilage cellulosic structure, short cellulosic rays and disorganized cellulose microfibrils in mucilage. The defects could be rescued by transgene complementation of trm4 alleles. Probably, this is a consequence of a disrupted organization of cortical microtubules, observed using fluorescently tagged tubulin proteins in trm4 SCE cells. Furthermore, TRM4 proteins co-aligned with microtubules and interacted directly with CELLULOSE SYNTHASE 3 in two independent assays. Together, the results indicate that TRM4 is essential for microtubule array organization and therefore correct cellulose orientation in the SCE cells, as well as the establishment of the subsequent mucilage architecture.
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Affiliation(s)
- Bo Yang
- Institute for Botany and Molecular Genetics (IBMG)BioEconomy Science CenterRWTH Aachen University52056AachenGermany
| | - Cătălin Voiniciuc
- Institute for Botany and Molecular Genetics (IBMG)BioEconomy Science CenterRWTH Aachen University52056AachenGermany
- Institute for Bio‐ and Geosciences (IBG‐2: Plant Sciences)Forschungszentrum Jülich52425JülichGermany
| | - Lanbao Fu
- Institute for Botany and Molecular Genetics (IBMG)BioEconomy Science CenterRWTH Aachen University52056AachenGermany
| | - Sabine Dieluweit
- Institute of Complex Systems (ICS‐7)Forschungszentrum Jülich52425JülichGermany
| | - Holger Klose
- Institute for Botany and Molecular Genetics (IBMG)BioEconomy Science CenterRWTH Aachen University52056AachenGermany
- Institute for Bio‐ and Geosciences (IBG‐2: Plant Sciences)Forschungszentrum Jülich52425JülichGermany
| | - Björn Usadel
- Institute for Botany and Molecular Genetics (IBMG)BioEconomy Science CenterRWTH Aachen University52056AachenGermany
- Institute for Bio‐ and Geosciences (IBG‐2: Plant Sciences)Forschungszentrum Jülich52425JülichGermany
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Harding SA, Hu H, Nyamdari B, Xue LJ, Naran R, Tsai CJ. Tubulins, rhythms and cell walls in poplar leaves: it's all in the timing. TREE PHYSIOLOGY 2018; 38:397-408. [PMID: 28927239 DOI: 10.1093/treephys/tpx104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/08/2017] [Indexed: 06/07/2023]
Abstract
Plant cell walls exhibit architectural and compositional changes throughout their development and in response to external cues. While tubulins are involved in cell wall biogenesis, much remains unknown about the scope of their involvement during the orchestration of this resource-demanding process. A transgenic approach coupled with cell wall compositional analysis, RNA-seq and mining of publicly available diurnal gene expression data was used to assess the involvement of tubulins in poplar leaf cell wall biogenesis. Leaf cell walls of transgenic poplar lines with constitutive overexpression of α-tubulin (TUA) exhibited an increased abundance of homogalacturonan, along with a reduction in xylose. These changes were traced to altered expression of UDP-glucuronic acid decarboxylase (GADC) in the transgenic leaves. A model is postulated by which altered diurnal control of TUA through its constitutive overexpression led to a metabolic tradeoff affecting cellular utilization of GADC substrate UDP-glucuronic acid. While there were no effects on cellulose, hemicellulose or lignin abundance, subtle effects on hemicellulose composition and associated gene expression were noted. In addition, expression and enzymatic activity of pectin methylesterase (PME) decreased in the transgenic leaves. The change is discussed in a context of increased levels of PME substrate homogalacturonan, slow stomatal kinetics and the fate of PME product methanol. Since stomatal opening and closing depend on fundamentally contrasting microtubule dynamics, the slowing of both processes in the transgenic lines as previously reported appears to be directly related to underlying cell wall compositional changes that were caused by tubulin manipulation.
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Affiliation(s)
- Scott A Harding
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Hao Hu
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
- Department of Plant Biology, Ecology & Evolution, Oklahoma State University, Stillwater, OK 74078, USA
| | - Batbayar Nyamdari
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Liang-Jiao Xue
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Radnaa Naran
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Chung-Jui Tsai
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
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14
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Sinclair R, Rosquete MR, Drakakaki G. Post-Golgi Trafficking and Transport of Cell Wall Components. FRONTIERS IN PLANT SCIENCE 2018; 9:1784. [PMID: 30581448 PMCID: PMC6292943 DOI: 10.3389/fpls.2018.01784] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 11/16/2018] [Indexed: 05/13/2023]
Abstract
The cell wall, a complex macromolecular composite structure surrounding and protecting plant cells, is essential for development, signal transduction, and disease resistance. This structure is also integral to cell expansion, as its tensile resistance is the primary balancing mechanism against internal turgor pressure. Throughout these processes, the biosynthesis, transport, deposition, and assembly of cell wall polymers are tightly regulated. The plant endomembrane system facilitates transport of polysaccharides, polysaccharide biosynthetic and modifying enzymes and glycoproteins through vesicle trafficking pathways. Although a number of enzymes involved in cell wall biosynthesis have been identified, comparatively little is known about the transport of cell wall polysaccharides and glycoproteins by the endomembrane system. This review summarizes our current understanding of trafficking of cell wall components during cell growth and cell division. Emerging technologies, such as vesicle glycomics, are also discussed as promising avenues to gain insights into the trafficking of structural polysaccharides to the apoplast.
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15
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Fan C, Li Y, Hu Z, Hu H, Wang G, Li A, Wang Y, Tu Y, Xia T, Peng L, Feng S. Ectopic expression of a novel OsExtensin-like gene consistently enhances plant lodging resistance by regulating cell elongation and cell wall thickening in rice. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:254-263. [PMID: 28574641 PMCID: PMC5785348 DOI: 10.1111/pbi.12766] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/30/2017] [Accepted: 05/29/2017] [Indexed: 05/17/2023]
Abstract
Plant lodging resistance is an important integrative agronomic trait of grain yield and quality in crops. Although extensin proteins are tightly associated with plant cell growth and cell wall construction, little has yet been reported about their impacts on plant lodging resistance. In this study, we isolated a novel extensin-like (OsEXTL) gene in rice, and selected transgenic rice plants that expressed OsEXTL under driven with two distinct promoters. Despite different OsEXTL expression levels, two-promoter-driven OsEXTL-transgenic plants, compared to a rice cultivar and an empty vector, exhibited significantly reduced cell elongation in stem internodes, leading to relatively shorter plant heights by 7%-10%. Meanwhile, the OsEXTL-transgenic plants showed remarkably thickened secondary cell walls with higher cellulose levels in the mature plants, resulting in significantly increased detectable mechanical strength (extension and pushing forces) in the mature transgenic plants. Due to reduced plant height and increased plant mechanical strength, the OsEXTL-transgenic plants were detected with largely enhanced lodging resistances in 3 years field experiments, compared to those of the rice cultivar ZH11. In addition, despite relatively short plant heights, the OsEXTL-transgenic plants maintain normal grain yields and biomass production, owing to their increased cellulose levels and thickened cell walls. Hence, this study demonstrates a largely improved lodging resistance in the OsEXTL-transgenic rice plants, and provides insights into novel extensin functions in plant cell growth and development, cell wall network construction and wall structural remodelling.
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Affiliation(s)
- Chunfen Fan
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ying Li
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Zhen Hu
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Huizhen Hu
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Guangya Wang
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ao Li
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Youmei Wang
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Yuanyuan Tu
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Tao Xia
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Liangcai Peng
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Shengqiu Feng
- Biomass and Bioenergy Research CentreHuazhong Agricultural UniversityWuhanChina
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
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16
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McFarlane HE, Lee EK, van Bezouwen LS, Ross B, Rosado A, Samuels AL. Multiscale Structural Analysis of Plant ER-PM Contact Sites. PLANT & CELL PHYSIOLOGY 2017; 58:478-484. [PMID: 28100648 DOI: 10.1093/pcp/pcw224] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 12/14/2016] [Indexed: 05/24/2023]
Abstract
Membrane contact sites are recognized across eukaryotic systems as important nanostructures. Endoplasmic reticulum (ER)-plasma membrane (PM) contact sites (EPCS) are involved in excitation-contraction coupling, signaling, and plant responses to stress. In this report, we perform a multiscale structural analysis of Arabidopsis EPCS that combines live cell imaging, quantitative transmission electron microscopy (TEM) and electron tomography over a developmental gradient. To place EPCS in the context of the entire cortical ER, we examined green fluorescent protein (GFP)-HDEL in living cells over a developmental gradient, then Synaptotagmin1 (SYT1)-GFP was used as a specific marker of EPCS. In all tissues examined, young, rapidly elongating cells showed lamellar cortical ER and higher density of SYT1-GFP puncta, while in mature cells the cortical ER network was tubular, highly dynamic and had fewer SYT1-labeled puncta. The higher density of EPCS in young cells was verified by quantitative TEM of cryo-fixed tissues. For all cell types, the size of each EPCS had a consistent range in length along the PM from 50 to 300 nm, with microtubules and ribosomes excluded from the EPCS. The structural characterization of EPCS in different plant tissues, and the correlation of EPCS densities over developmental gradients illustrate how ER-PM communication evolves in response to cellular expansion.
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Affiliation(s)
- Heather E McFarlane
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
- School of Biosciences, University of Melbourne, Australia
| | - Eun Kyoung Lee
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
| | - Laura S van Bezouwen
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
- Laboratory of Cell Biology, Wageningen University, PB Wageningen, The Netherlands
- Cryo-Electron Microscopy, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, CH Utrecht, The Netherlands
| | - Bradford Ross
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
| | - Abel Rosado
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
| | - A Lacey Samuels
- Department of Botany, University of British Columbia, University Blvd., Vancouver, Canada
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17
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Vukašinović N, Oda Y, Pejchar P, Synek L, Pečenková T, Rawat A, Sekereš J, Potocký M, Žárský V. Microtubule-dependent targeting of the exocyst complex is necessary for xylem development in Arabidopsis. THE NEW PHYTOLOGIST 2017; 213:1052-1067. [PMID: 27801942 DOI: 10.1111/nph.14267] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 09/13/2016] [Indexed: 05/23/2023]
Abstract
Cortical microtubules (MTs) play a major role in the patterning of secondary cell wall (SCW) thickenings in tracheary elements (TEs) by determining the sites of SCW deposition. The EXO70A1 subunit of the exocyst secretory vesicle tethering complex was implicated to be important for TE development via the MT interaction. We investigated the subcellular localization of several exocyst subunits in the xylem of Arabidopsis thaliana and analyzed the functional significance of exocyst-mediated trafficking in TE development. Live cell imaging of fluorescently tagged exocyst subunits in TE using confocal microscopy and protein-protein interaction assays were performed to describe the role of the exocyst and its partners in TE development. In TEs, exocyst subunits were localized to the sites of SCW deposition in an MT-dependent manner. We propose that the mechanism of exocyst targeting to MTs involves the direct interaction of exocyst subunits with the COG2 protein. We demonstrated the importance of a functional exocyst subunit EXO84b for normal TE development and showed that the deposition of SCW constituents is partially compromised, possibly as a result of the mislocalization of secondary cellulose synthase in exocyst mutants. We conclude that the exocyst complex is an important factor bridging the pattern defined by cortical MTs with localized secretion of the SCW in developing TEs.
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Affiliation(s)
- Nemanja Vukašinović
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, 128 44, Prague 2, Czech Republic
| | - Yoshihisa Oda
- Center for Frontier Research, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
- Department of Genetics, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Přemysl Pejchar
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
| | - Lukáš Synek
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
| | - Tamara Pečenková
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
| | - Anamika Rawat
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, 128 44, Prague 2, Czech Republic
| | - Juraj Sekereš
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, 128 44, Prague 2, Czech Republic
| | - Martin Potocký
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
| | - Viktor Žárský
- Institute of Experimental Botany, v.v.i., The Czech Academy of Sciences, 16502, Prague 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, 128 44, Prague 2, Czech Republic
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18
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van de Meene AML, Doblin MS, Bacic A. The plant secretory pathway seen through the lens of the cell wall. PROTOPLASMA 2017; 254:75-94. [PMID: 26993347 DOI: 10.1007/s00709-016-0952-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 01/27/2016] [Accepted: 02/01/2016] [Indexed: 05/18/2023]
Abstract
Secretion in plant cells is often studied by looking at well-characterised, evolutionarily conserved membrane proteins associated with particular endomembrane compartments. Studies using live cell microscopy and fluorescent proteins have illuminated the highly dynamic nature of trafficking, and electron microscopy studies have resolved the ultrastructure of many compartments. Biochemical and molecular analyses have further informed about the function of particular proteins and endomembrane compartments. In plants, there are over 40 cell types, each with highly specialised functions, and hence potential variations in cell biological processes and cell wall structure. As the primary function of secretion in plant cells is for the biosynthesis of cell wall polysaccharides and apoplastic transport complexes, it follows that utilising our knowledge of cell wall glycosyltransferases (GTs) and their polysaccharide products will inform us about secretion. Indeed, this knowledge has led to novel insights into the secretory pathway, including previously unseen post-TGN secretory compartments. Conversely, our knowledge of trafficking routes of secretion will inform us about polarised and localised deposition of cell walls and their constituent polysaccharides/glycoproteins. In this review, we look at what is known about cell wall biosynthesis and the secretory pathway and how the different approaches can be used in a complementary manner to study secretion and provide novel insights into these processes.
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Affiliation(s)
- A M L van de Meene
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - M S Doblin
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Antony Bacic
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria, 3010, Australia.
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Fan C, Feng S, Huang J, Wang Y, Wu L, Li X, Wang L, Tu Y, Xia T, Li J, Cai X, Peng L. AtCesA8-driven OsSUS3 expression leads to largely enhanced biomass saccharification and lodging resistance by distinctively altering lignocellulose features in rice. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:221. [PMID: 28932262 PMCID: PMC5603028 DOI: 10.1186/s13068-017-0911-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/08/2017] [Indexed: 05/03/2023]
Abstract
BACKGROUND Biomass recalcitrance and plant lodging are two complex traits that tightly associate with plant cell wall structure and features. Although genetic modification of plant cell walls can potentially reduce recalcitrance for enhancing biomass saccharification, it remains a challenge to maintain a normal growth with enhanced biomass yield and lodging resistance in transgenic plants. Sucrose synthase (SUS) is a key enzyme to regulate carbon partitioning by providing UDP-glucose as substrate for cellulose and other polysaccharide biosynthesis. Although SUS transgenic plants have reportedly exhibited improvement on the cellulose and starch based traits, little is yet reported about SUS impacts on both biomass saccharification and lodging resistance. In this study, we selected the transgenic rice plants that expressed OsSUS3 genes when driven by the AtCesA8 promoter specific for promoting secondary cell wall cellulose synthesis in Arabidopsis. We examined biomass saccharification and lodging resistance in the transgenic plants and detected their cell wall structures and wall polymer features. RESULTS During two-year field experiments, the selected AtCesA8::SUS3 transgenic plants maintained a normal growth with slightly increased biomass yields. The four independent transgenic lines exhibited much higher biomass enzymatic saccharification and bioethanol production under chemical pretreatments at P < 0.01 levels, compared with the controls of rice cultivar and empty vector transgenic line. Notably, all transgenic lines showed a consistently enhanced lodging resistance with the increasing extension and pushing forces. Correlation analysis suggested that the reduced cellulose crystallinity was a major factor for largely enhanced biomass saccharification and lodging resistance in transgenic rice plants. In addition, the cell wall thickenings with the increased cellulose and hemicelluloses levels should also contribute to plant lodging resistance. Hence, this study has proposed a mechanistic model that shows how OsSUS3 regulates cellulose and hemicelluloses biosyntheses resulting in reduced cellulose crystallinity and increased wall thickness, thereby leading to large improvements of both biomass saccharification and lodging resistance in transgenic rice plants. CONCLUSIONS This study has demonstrated that the AtCesA8::SUS3 transgenic rice plants exhibited largely improved biomass saccharification and lodging resistance by reducing cellulose crystallinity and increasing cell wall thickness. It also suggests a powerful genetic approach for cell wall modification in bioenergy crops.
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Affiliation(s)
- Chunfen Fan
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Shengqiu Feng
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiangfeng Huang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yanting Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Leiming Wu
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xukai Li
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Lingqiang Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yuanyuan Tu
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Tao Xia
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jingyang Li
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- HaiKou Experimental Station, Chinese Academy of Tropical Agricultural Sciences, Haikou, 570102 China
| | - Xiwen Cai
- Department of Plant Science, North Dakota State University, Fargo, ND USA
| | - Liangcai Peng
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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Zhang Y, Nikolovski N, Sorieul M, Vellosillo T, McFarlane HE, Dupree R, Kesten C, Schneider R, Driemeier C, Lathe R, Lampugnani E, Yu X, Ivakov A, Doblin MS, Mortimer JC, Brown SP, Persson S, Dupree P. Golgi-localized STELLO proteins regulate the assembly and trafficking of cellulose synthase complexes in Arabidopsis. Nat Commun 2016; 7:11656. [PMID: 27277162 PMCID: PMC4906169 DOI: 10.1038/ncomms11656] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 04/15/2016] [Indexed: 01/24/2023] Open
Abstract
As the most abundant biopolymer on Earth, cellulose is a key structural component of the plant cell wall. Cellulose is produced at the plasma membrane by cellulose synthase (CesA) complexes (CSCs), which are assembled in the endomembrane system and trafficked to the plasma membrane. While several proteins that affect CesA activity have been identified, components that regulate CSC assembly and trafficking remain unknown. Here we show that STELLO1 and 2 are Golgi-localized proteins that can interact with CesAs and control cellulose quantity. In the absence of STELLO function, the spatial distribution within the Golgi, secretion and activity of the CSCs are impaired indicating a central role of the STELLO proteins in CSC assembly. Point mutations in the predicted catalytic domains of the STELLO proteins indicate that they are glycosyltransferases facing the Golgi lumen. Hence, we have uncovered proteins that regulate CSC assembly in the plant Golgi apparatus.
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Affiliation(s)
- Yi Zhang
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Nino Nikolovski
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Mathias Sorieul
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Tamara Vellosillo
- Energy Biosciences Institute, and Plant and Microbial Biology Department, University of California, Berkeley, California 94720, USA
| | - Heather E McFarlane
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ray Dupree
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Christopher Kesten
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - René Schneider
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Carlos Driemeier
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo CEP 13083-970, Brazil
| | - Rahul Lathe
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Edwin Lampugnani
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Xiaolan Yu
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Alexander Ivakov
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Monika S Doblin
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Jenny C Mortimer
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Steven P Brown
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Staffan Persson
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany.,School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
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21
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Simpson JP, Thrower N, Ohlrogge JB. How did nature engineer the highest surface lipid accumulation among plants? Exceptional expression of acyl-lipid-associated genes for the assembly of extracellular triacylglycerol by Bayberry (Myrica pensylvanica) fruits. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1243-1252. [PMID: 26869450 DOI: 10.1016/j.bbalip.2016.01.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/28/2016] [Accepted: 01/29/2016] [Indexed: 10/22/2022]
Abstract
Bayberry (Myrica pensylvanica) fruits are covered with a remarkably thick layer of crystalline wax consisting of triacylglycerol (TAG) and diacylglycerol (DAG) esterified exclusively with saturated fatty acids. As the only plant known to accumulate soluble glycerolipids as a major component of surface waxes, Bayberry represents a novel system to investigate neutral lipid biosynthesis and lipid secretion by vegetative plant cells. The assembly of Bayberry wax is distinct from conventional TAG and other surface waxes, and instead proceeds through a pathway related to cutin synthesis (Simpson and Ohlrogge, 2016). In this study, microscopic examination revealed that the fruit tissue that produces and secretes wax (Bayberry knobs) is fully developed before wax accumulates and that wax is secreted to the surface without cell disruption. Comparison of transcript expression to genetically related tissues (Bayberry leaves, M. rubra fruits), cutin-rich tomato and cherry fruit epidermis, and to oil-rich mesocarp and seeds, revealed exceptionally high expression of 13 transcripts for acyl-lipid metabolism together with down-regulation of fatty acid oxidases and desaturases. The predicted protein sequences of the most highly expressed lipid-related enzyme-encoding transcripts in Bayberry knobs are 100% identical to the sequences from Bayberry leaves, which do not produce surface DAG or TAG. Together, these results indicate that TAG biosynthesis and secretion in Bayberry is achieved by both up and down-regulation of a small subset of genes related to the biosynthesis of cutin and saturated fatty acids, and also implies that modifications in gene expression, rather than evolution of new gene functions, was the major mechanism by which Bayberry evolved its specialized lipid metabolism. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Jeffrey P Simpson
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA.
| | - Nicholas Thrower
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA.
| | - John B Ohlrogge
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA.
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22
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Swamy PS, Hu H, Pattathil S, Maloney VJ, Xiao H, Xue LJ, Chung JD, Johnson VE, Zhu Y, Peter GF, Hahn MG, Mansfield SD, Harding SA, Tsai CJ. Tubulin perturbation leads to unexpected cell wall modifications and affects stomatal behaviour in Populus. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6507-18. [PMID: 26246616 PMCID: PMC4588895 DOI: 10.1093/jxb/erv383] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cortical microtubules are integral to plant morphogenesis, cell wall synthesis, and stomatal behaviour, presumably by governing cellulose microfibril orientation. Genetic manipulation of tubulins often leads to abnormal plant development, making it difficult to probe additional roles of cortical microtubules in cell wall biogenesis. Here, it is shown that expressing post-translational C-terminal modification mimics of α-tubulin altered cell wall characteristics and guard cell dynamics in transgenic Populus tremula x alba that otherwise appear normal. 35S promoter-driven transgene expression was high in leaves but unusually low in xylem, suggesting high levels of tubulin transgene expression were not tolerated in wood-forming tissues during regeneration of transformants. Cellulose, hemicellulose, and lignin contents were unaffected in transgenic wood, but expression of cell wall-modifying enzymes, and extractability of lignin-bound pectin and xylan polysaccharides were increased in developing xylem. The results suggest that pectin and xylan polysaccharides deposited early during cell wall biogenesis are more sensitive to subtle tubulin perturbation than cellulose and matrix polysaccharides deposited later. Tubulin perturbation also affected guard cell behaviour, delaying drought-induced stomatal closure as well as light-induced stomatal opening in leaves. Pectins have been shown to confer cell wall flexibility critical for reversible stomatal movement, and results presented here are consistent with microtubule involvement in this process. Taken together, the data show the value of growth-compatible tubulin perturbations for discerning microtubule functions, and add to the growing body of evidence for microtubule involvement in non-cellulosic polysaccharide assembly during cell wall biogenesis.
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Affiliation(s)
- Prashant S Swamy
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
| | - Hao Hu
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Victoria J Maloney
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Hui Xiao
- Laboratory for Macromolecular Analysis and Proteomics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Liang-Jiao Xue
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Jeng-Der Chung
- Division of Silviculture, Taiwan Forestry Research Institute, Taipei 10066, Taiwan
| | - Virgil E Johnson
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Yingying Zhu
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Gary F Peter
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL 32611, USA
| | - Michael G Hahn
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Scott A Harding
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Chung-Jui Tsai
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
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23
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Francoz E, Ranocha P, Burlat V, Dunand C. Arabidopsis seed mucilage secretory cells: regulation and dynamics. TRENDS IN PLANT SCIENCE 2015; 20:515-24. [PMID: 25998090 DOI: 10.1016/j.tplants.2015.04.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/02/2015] [Accepted: 04/15/2015] [Indexed: 05/21/2023]
Abstract
Seeds from various angiosperm species produce polysaccharide mucilage facilitating germination and, therefore, conferring major evolutionary advantages. The seed epidermal mucilage secretory cells (MSCs) undergo numerous tightly controlled changes of their extracellular matrixes (ECMs) throughout seed development. Recently, major progress based on the model species Arabidopsis thaliana was published, including the identification of 54 genes necessary for mucilage synthesis and release. Here, we review these genes that constitute the so-called 'MSC toolbox', within which transcription factors and proteins related to polysaccharide production, secretion, modification, and stabilization are the most abundant and belong to complex regulatory networks. We also discuss how seed coat 'omics data-mining, comparative genomics, and operon-like gene cluster studies will provide means to identify new members of the MSC toolbox.
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Affiliation(s)
- Edith Francoz
- Université de Toulouse, UPS, UMR 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326 Castanet-Tolosan, France; CNRS, UMR 5546, BP 42617, F-31326 Castanet-Tolosan, France
| | - Philippe Ranocha
- Université de Toulouse, UPS, UMR 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326 Castanet-Tolosan, France; CNRS, UMR 5546, BP 42617, F-31326 Castanet-Tolosan, France
| | - Vincent Burlat
- Université de Toulouse, UPS, UMR 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326 Castanet-Tolosan, France; CNRS, UMR 5546, BP 42617, F-31326 Castanet-Tolosan, France.
| | - Christophe Dunand
- Université de Toulouse, UPS, UMR 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326 Castanet-Tolosan, France; CNRS, UMR 5546, BP 42617, F-31326 Castanet-Tolosan, France.
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24
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Kulich I, Vojtíková Z, Glanc M, Ortmannová J, Rasmann S, Žárský V. Cell wall maturation of Arabidopsis trichomes is dependent on exocyst subunit EXO70H4 and involves callose deposition. PLANT PHYSIOLOGY 2015; 168:120-31. [PMID: 25767057 PMCID: PMC4424025 DOI: 10.1104/pp.15.00112] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Accepted: 03/10/2015] [Indexed: 05/22/2023]
Abstract
Arabidopsis (Arabidopsis thaliana) leaf trichomes are single-cell structures with a well-studied development, but little is understood about their function. Developmental studies focused mainly on the early shaping stages, and little attention has been paid to the maturation stage. We focused on the EXO70H4 exocyst subunit, one of the most up-regulated genes in the mature trichome. We uncovered EXO70H4-dependent development of the secondary cell wall layer, highly autofluorescent and callose rich, deposited only in the upper part of the trichome. The boundary is formed between the apical and the basal parts of mature trichome by a callose ring that is also deposited in an EXO70H4-dependent manner. We call this structure the Ortmannian ring (OR). Both the secondary cell wall layer and the OR are absent in the exo70H4 mutants. Ecophysiological aspects of the trichome cell wall thickening include interference with antiherbivore defense and heavy metal accumulation. Ultraviolet B light induces EXO70H4 transcription in a CONSTITUTIVE PHOTOMORPHOGENIC1-dependent way, resulting in stimulation of trichome cell wall thickening and the OR biogenesis. EXO70H4-dependent trichome cell wall hardening is a unique phenomenon, which may be conserved among a variety of the land plants. Our analyses support a concept that Arabidopsis trichome is an excellent model to study molecular mechanisms of secondary cell wall deposition.
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Affiliation(s)
- Ivan Kulich
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
| | - Zdeňka Vojtíková
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
| | - Matouš Glanc
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
| | - Jitka Ortmannová
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
| | - Sergio Rasmann
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
| | - Viktor Žárský
- Department of Experimental Plant Biology, Faculty of Sciences, Charles University, 12844 Prague, Czech Republic (I.K., Z.V., M.G., J.O., V.Z.);Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502 Prague, Czech Republic (J.O., V.Z.); andDepartment of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland (S.R.)
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25
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OsKinesin-13A is an active microtubule depolymerase involved in glume length regulation via affecting cell elongation. Sci Rep 2015; 5:9457. [PMID: 25807460 DOI: 10.1038/srep09457] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/06/2015] [Indexed: 01/25/2023] Open
Abstract
Grain size is an important trait influencing both the yield and quality of rice and its major determinant is glume size. However, how glume size is regulated remains largely unknown. Here, we report the characterization of OsKinesin-13A, which regulates cell elongation and glume length in rice. The mutant of OsKinesin-13A, sar1, displayed length reduction in grains and other organs including internodes, leaves and roots. The grain phenotype in sar1 was directly caused by reduction in glume length, which in turn restricted caryopsis size. Histological results revealed that length decrease in sar1 organs resulted from abnormalities in cell elongation. The orientation of cellulose microfibrils was defective in sar1. Consistently, sar1 showed reduced transverse orientation of cortical microtubules. Further observations demonstrated that microtubule turnover was decreased in sar1. OsKinesin-13A was shown to be an active microtubule depolymerase and mainly distributed on vesicles derived from the Golgi apparatus and destined for the cell surface. Thus, our results suggest that OsKinesin-13A utilizes its microtubule depolymerization activity to promote microtubule turnover, which may not only influence transverse orientation of cortical microtubules but also facilitate vesicle transport from the Golgi apparatus to the cell surface, and thus affects cellulose microfibril orientation and cell elongation.
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26
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Gendre D, Jonsson K, Boutté Y, Bhalerao RP. Journey to the cell surface--the central role of the trans-Golgi network in plants. PROTOPLASMA 2015; 252:385-98. [PMID: 25187082 DOI: 10.1007/s00709-014-0693-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 08/21/2014] [Indexed: 05/11/2023]
Abstract
The secretion of proteins, lipids, and carbohydrates to the cell surface is essential for plant development and adaptation. Secreted substances synthesized at the endoplasmic reticulum pass through the Golgi apparatus and trans-Golgi network (TGN) en route to the plasma membrane via the conventional secretion pathway. The TGN is morphologically and functionally distinct from the Golgi apparatus. The TGN is located at the crossroads of many trafficking pathways and regulates a range of crucial processes including secretion to the cell surface, transport to the vacuole, and the reception of endocytic cargo. This review outlines the TGN's central role in cargo secretion, showing that its behavior is more complex and controlled than the bulk-flow hypothesis suggests. Its formation, structure, and maintenance are discussed along with the formation and release of secretory vesicles.
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Affiliation(s)
- Delphine Gendre
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden,
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27
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North HM, Berger A, Saez-Aguayo S, Ralet MC. Understanding polysaccharide production and properties using seed coat mutants: future perspectives for the exploitation of natural variants. ANNALS OF BOTANY 2014; 114:1251-63. [PMID: 24607722 PMCID: PMC4195541 DOI: 10.1093/aob/mcu011] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/14/2014] [Indexed: 05/17/2023]
Abstract
BACKGROUND The epidermal cells of the seed coat of certain species accumulate polysaccharides during seed development for cell wall reinforcement or release on imbibition to form mucilage. Seed-coat epidermal cells show natural variation in their structure and mucilage production, which could explain the diverse ecophysiological roles proposed for the latter. Arabidopsis mucilage mutants have proved to be an important tool for the identification of genes involved in the production of seed-coat polysaccharides. SCOPE This review documents genes that have been characterized as playing a role in the differentiation of the epidermal cells of the arabidopsis seed coat, the natural variability in polysaccharide features of these cells and the physiological roles attributed to seed mucilage. CONCLUSIONS Seed-coat epidermal cells are an excellent model for the study of polysaccharide metabolism and properties. Intra- and interspecies natural variation in the differentiation of these epidermal cells is an under-exploited resource for such studies and promises to play an important part in improving our knowledge of polysaccharide production and ecophysiological function.
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Affiliation(s)
- Helen M North
- INRA, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France
| | - Adeline Berger
- INRA, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France
| | - Susana Saez-Aguayo
- INRA, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, Saclay Plant Sciences, F-78026 Versailles, France
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28
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Mitochondrial AtPAM16 is required for plant survival and the negative regulation of plant immunity. Nat Commun 2014; 4:2558. [PMID: 24153405 DOI: 10.1038/ncomms3558] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/04/2013] [Indexed: 12/21/2022] Open
Abstract
Proteins containing nucleotide-binding and leucine-rich repeat domains (NB-LRRs) serve as immune receptors in plants and animals. Negative regulation of immunity mediated by NB-LRR proteins is crucial, as their overactivation often leads to autoimmunity. Here we describe a new mutant, snc1-enhancing (muse) forward genetic screen, targeting unknown negative regulators of NB-LRR-mediated resistance in Arabidopsis. From the screen, we identify MUSE5, which is renamed as AtPAM16 because it encodes the ortholog of yeast PAM16, part of the mitochondrial inner membrane protein import motor. Consistently, AtPAM16-GFP localizes to the mitochondrial inner membrane. AtPAM16L is a paralog of AtPAM16. Double mutant Atpam16-1 Atpam16l is lethal, indicating that AtPAM16 function is essential. Single mutant Atpam16 plants exhibit a smaller size and enhanced resistance against virulent pathogens. They also display elevated reactive oxygen species (ROS) accumulation. Therefore, AtPAM16 seems to be involved in importing a negative regulator of plant immunity into mitochondria, thus protecting plants from over-accumulation of ROS and preventing autoimmunity.
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29
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Kim SJ, Brandizzi F. The plant secretory pathway: an essential factory for building the plant cell wall. PLANT & CELL PHYSIOLOGY 2014; 55:687-93. [PMID: 24401957 DOI: 10.1093/pcp/pct197] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
For building and maintaining the complex structure of the surrounding wall throughout their life, plant cells rely on the endomembrane system, which functions as the main provider and transporter of cell wall constituents. Efforts to understand the mechanisms of synthesis and transport of cell wall materials have been generating valuable information for diverse practical applications. Nonetheless, the identity of the endomembrane components necessary for the transport of cell wall enzymes and polysaccharides is not well known. Evidence indicates that plant cells can accomplish secretion of cell wall constituents through multiple pathways during development or under stress conditions and, that compared with other eukaryotes, they rely on a highly diversified toolkit of proteins for membrane traffic. This suggests that production of the cell wall in plants consists of intricate and highly regulated pathways. In this review, we summarize important discoveries that have allowed the activities of the plant secretory pathway to be linked to the production and deposition of cell wall-synthesizing enzymes and polysaccharides.
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Affiliation(s)
- Sang-Jin Kim
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
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30
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McFarlane HE, Watanabe Y, Yang W, Huang Y, Ohlrogge J, Samuels AL. Golgi- and trans-Golgi network-mediated vesicle trafficking is required for wax secretion from epidermal cells. PLANT PHYSIOLOGY 2014; 164:1250-60. [PMID: 24468625 PMCID: PMC3938617 DOI: 10.1104/pp.113.234583] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/16/2014] [Indexed: 05/18/2023]
Abstract
Lipid secretion from epidermal cells to the plant surface is essential to create the protective plant cuticle. Cuticular waxes are unusual secretory products, consisting of a variety of highly hydrophobic compounds including saturated very-long-chain alkanes, ketones, and alcohols. These compounds are synthesized in the endoplasmic reticulum (ER) but must be trafficked to the plasma membrane for export by ATP-binding cassette transporters. To test the hypothesis that wax components are trafficked via the endomembrane system and packaged in Golgi-derived secretory vesicles, Arabidopsis (Arabidopsis thaliana) stem wax secretion was assayed in a series of vesicle-trafficking mutants, including gnom like1-1 (gnl1-1), transport particle protein subunit120-4, and echidna (ech). Wax secretion was dependent upon GNL1 and ECH. Independent of secretion phenotypes, mutants with altered ER morphology also had decreased wax biosynthesis phenotypes, implying that the biosynthetic capacity of the ER is closely related to its structure. These results provide genetic evidence that wax export requires GNL1- and ECH-dependent endomembrane vesicle trafficking to deliver cargo to plasma membrane-localized ATP-binding cassette transporters.
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31
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Synek L, Sekereš J, Žárský V. The exocyst at the interface between cytoskeleton and membranes in eukaryotic cells. FRONTIERS IN PLANT SCIENCE 2014; 4:543. [PMID: 24427163 PMCID: PMC3877765 DOI: 10.3389/fpls.2013.00543] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/12/2013] [Indexed: 05/07/2023]
Abstract
Delivery and final fusion of the secretory vesicles with the relevant target membrane are hierarchically organized and reciprocally interconnected multi-step processes involving not only specific protein-protein interactions, but also specific protein-phospholipid interactions. The exocyst was discovered as a tethering complex mediating initial encounter of arriving exocytic vesicles with the plasma membrane. The exocyst complex is regulated by Rab and Rho small GTPases, resulting in docking of exocytic vesicles to the plasma membrane (PM) and finally their fusion mediated by specific SNARE complexes. In model Opisthokont cells, the exocyst was shown to directly interact with both microtubule and microfilament cytoskeleton and related motor proteins as well as with the PM via phosphatidylinositol 4, 5-bisphosphate specific binding, which directly affects cortical cytoskeleton and PM dynamics. Here we summarize the current knowledge on exocyst-cytoskeleton-PM interactions in order to open a perspective for future research in this area in plant cells.
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Affiliation(s)
- Lukáš Synek
- Laboratory of Cell Biology, Institute of Experimental Botany, Academy of Sciences of the Czech RepublicPrague, Czech Republic
| | - Juraj Sekereš
- Laboratory of Cell Biology, Institute of Experimental Botany, Academy of Sciences of the Czech RepublicPrague, Czech Republic
- Laboratory of Plant Cell Biology, Department of Experimental Plant Biology, Faculty of Science, Charles University in PraguePrague, Czech Republic
| | - Viktor Žárský
- Laboratory of Cell Biology, Institute of Experimental Botany, Academy of Sciences of the Czech RepublicPrague, Czech Republic
- Laboratory of Plant Cell Biology, Department of Experimental Plant Biology, Faculty of Science, Charles University in PraguePrague, Czech Republic
- *Correspondence: Viktor Žárský, Laboratory of Plant Cell Biology, Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, Vinicna 5, 12844 Prague, Czech Republic e-mail:
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McFarlane HE, Watanabe Y, Gendre D, Carruthers K, Levesque-Tremblay G, Haughn GW, Bhalerao RP, Samuels L. Cell wall polysaccharides are mislocalized to the Vacuole in echidna mutants. PLANT & CELL PHYSIOLOGY 2013; 54:1867-1880. [PMID: 24058145 DOI: 10.1093/pcp/pct129] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
During cell wall biosynthesis, the Golgi apparatus is the platform for cell wall matrix biosynthesis and the site of packaging, of both matrix polysaccharides and proteins, into secretory vesicles with the correct targeting information. The objective of this study was to dissect the post-Golgi trafficking of cell wall polysaccharides using echidna as a vesicle traffic mutant of Arabidopsis thaliana and the pectin-secreting cells of the seed coat as a model system. ECHIDNA encodes a trans-Golgi network (TGN)-localized protein, which was previously shown to be required for proper structure and function of the secretory pathway. In echidna mutants, some cell wall matrix polysaccharides accumulate inside cells, rather than being secreted to the apoplast. In this study, live cell imaging of fluorescent protein markers as well as transmission electron microscopy (TEM)/immunoTEM of cryofixed seed coat cells were used to examine the consequences of TGN disorganization in echidna mutants under conditions of high polysaccharide production and secretion. While in wild-type seed coat cells, pectin is secreted to the apical surface, in echidna, polysaccharides accumulate in post-Golgi vesicles, the central lytic vacuole and endoplasmic reticulum-derived bodies. In contrast, proteins were partially mistargeted to internal multilamellar membranes in echidna. These results suggest that while secretion of both cell wall polysaccharides and proteins at the TGN requires ECHIDNA, different vesicle trafficking components may mediate downstream events in their secretion from the TGN.
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Affiliation(s)
- Heather E McFarlane
- Department of Botany, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
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Haikonen T, Rajamäki ML, Valkonen JPT. Interaction of the microtubule-associated host protein HIP2 with viral helper component proteinase is important in infection with potato virus A. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:734-44. [PMID: 23489059 DOI: 10.1094/mpmi-01-13-0023-r] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Microtubules (MT) outline and maintain the overall shape of cells and can reorganize cellular membranes to serve as sites of RNA virus replication. Here, we provide data on involvement of an MT-associated protein in infection of plants with a potyvirus, Potato virus A (PVA), representing the largest family of plant-infecting RNA viruses. Our results showed that helper-component proteinase (HCpro)-interacting protein 2 (HIP2) of potato (Solanum tuberosum) is an MT-associated protein similar to Arabidopsis SPR2. Virus-induced silencing of HIP2 in Nicotiana benthamiana resulted in a spiral-like growth phenotype, similar to the Arabidopsis spr2 mutant, and the spr2 phenotype in Arabidopsis was complemented with potato HIP2. HCpro of PVA interacted with HIP2 of potato and tobacco (Nicotiana tabacum). The interaction was detected by bimolecular fluorescence complementation in PVA-infected leaves on MT and MT intersections at the cell cortex. HIP2-HCpro interaction was determined by the C-proximal α-helix-rich domain of HIP2, whereas the N-proximal putative TOG domain and the central coiled-coil domain of HIP2 controlled HIP2 dimerization and binding to MT. Accumulation of PVA was significantly reduced in the HIP2-silenced leaves of N. benthamiana, which indicates that HIP2-HCpro interactions are important for virus infection.
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Affiliation(s)
- Tuuli Haikonen
- Department of Agricultural Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland
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Gendre D, McFarlane HE, Johnson E, Mouille G, Sjödin A, Oh J, Levesque-Tremblay G, Watanabe Y, Samuels L, Bhalerao RP. Trans-Golgi network localized ECHIDNA/Ypt interacting protein complex is required for the secretion of cell wall polysaccharides in Arabidopsis. THE PLANT CELL 2013; 25:2633-46. [PMID: 23832588 PMCID: PMC3753388 DOI: 10.1105/tpc.113.112482] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The secretion of cell wall polysaccharides through the trans-Golgi network (TGN) is required for plant cell elongation. However, the components mediating the post-Golgi secretion of pectin and hemicellulose, the two major cell wall polysaccharides, are largely unknown. We identified evolutionarily conserved YPT/RAB GTPase Interacting Protein 4a (YIP4a) and YIP4b (formerly YIP2), which form a TGN-localized complex with ECHIDNA (ECH) in Arabidopsis thaliana. The localization of YIP4 and ECH proteins at the TGN is interdependent and influences the localization of VHA-a1 and SYP61, which are key components of the TGN. YIP4a and YIP4b act redundantly, and the yip4a yip4b double mutants have a cell elongation defect. Genetic, biochemical, and cell biological analyses demonstrate that the ECH/YIP4 complex plays a key role in TGN-mediated secretion of pectin and hemicellulose to the cell wall in dark-grown hypocotyls and in secretory cells of the seed coat. In keeping with these observations, Fourier transform infrared microspectroscopy analysis revealed that the ech and yip4a yip4b mutants exhibit changes in their cell wall composition. Overall, our results reveal a TGN subdomain defined by ECH/YIP4 that is required for the secretion of pectin and hemicellulose and distinguishes the role of the TGN in secretion from its roles in endocytic and vacuolar trafficking.
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Affiliation(s)
- Delphine Gendre
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umea, Sweden
| | - Heather E. McFarlane
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Errin Johnson
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umea, Sweden
| | - Gregory Mouille
- Institut Jean-Pierre Bourgin, Unité Mixte de Recherche 1318, Institut National de la Recherche Agronomique–AgroParisTech, Institut National de la Recherche Agronomique Centre de Versailles-Grignon, 78026 Versailles cedex, France
| | - Andreas Sjödin
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umea, Sweden
| | - Jaesung Oh
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umea, Sweden
| | | | - Yoichiro Watanabe
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Lacey Samuels
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Rishikesh P. Bhalerao
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umea, Sweden
- Address correspondence to
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Sampathkumar A, Gutierrez R, McFarlane HE, Bringmann M, Lindeboom J, Emons AM, Samuels L, Ketelaar T, Ehrhardt DW, Persson S. Patterning and lifetime of plasma membrane-localized cellulose synthase is dependent on actin organization in Arabidopsis interphase cells. PLANT PHYSIOLOGY 2013; 162:675-88. [PMID: 23606596 PMCID: PMC3668062 DOI: 10.1104/pp.113.215277] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Accepted: 04/18/2013] [Indexed: 05/17/2023]
Abstract
The actin and microtubule cytoskeletons regulate cell shape across phyla, from bacteria to metazoans. In organisms with cell walls, the wall acts as a primary constraint of shape, and generation of specific cell shape depends on cytoskeletal organization for wall deposition and/or cell expansion. In higher plants, cortical microtubules help to organize cell wall construction by positioning the delivery of cellulose synthase (CesA) complexes and guiding their trajectories to orient newly synthesized cellulose microfibrils. The actin cytoskeleton is required for normal distribution of CesAs to the plasma membrane, but more specific roles for actin in cell wall assembly and organization remain largely elusive. We show that the actin cytoskeleton functions to regulate the CesA delivery rate to, and lifetime of CesAs at, the plasma membrane, which affects cellulose production. Furthermore, quantitative image analyses revealed that actin organization affects CesA tracking behavior at the plasma membrane and that small CesA compartments were associated with the actin cytoskeleton. By contrast, localized insertion of CesAs adjacent to cortical microtubules was not affected by the actin organization. Hence, both actin and microtubule cytoskeletons play important roles in regulating CesA trafficking, cellulose deposition, and organization of cell wall biogenesis.
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Cvrčková F. Formins: emerging players in the dynamic plant cell cortex. SCIENTIFICA 2012; 2012:712605. [PMID: 24278734 PMCID: PMC3820618 DOI: 10.6064/2012/712605] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 09/16/2012] [Indexed: 05/11/2023]
Abstract
Formins (FH2 proteins) are an evolutionarily conserved family of eukaryotic proteins, sharing the common FH2 domain. While they have been, until recently, understood mainly as actin nucleators, formins are also engaged in various additional aspects of cytoskeletal organization and signaling, including, but not limited to, the crosstalk between the actin and microtubule networks. A surprising diversity of domain organizations has been discovered among the FH2 proteins, and specific domain setups have been found in plants. Seed plants have two clades of formins, one of them (Class I) containing mostly transmembrane proteins, while members of the other one (Class II) may be anchored to membranes via a putative membrane-binding domain related to the PTEN antioncogene. Thus, plant formins present good candidates for possible mediators of coordination of the cortical actin and microtubule cytoskeletons, as well as their attachment to the plasma membrane, that is, aspects of cell cortex organization likely to be important for cell and tissue morphogenesis. Although experimental studies of plant formin function are hampered by the large number of formin genes and their functional redundancy, recent experimental work has already resulted in some remarkable insights into the function of FH2 proteins in plants.
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Affiliation(s)
- Fatima Cvrčková
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 43 Prague, Czech Republic
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Quilichini TD, Friedmann MC, Samuels AL, Douglas CJ. ATP-binding cassette transporter G26 is required for male fertility and pollen exine formation in Arabidopsis. PLANT PHYSIOLOGY 2010; 154:678-90. [PMID: 20732973 PMCID: PMC2949020 DOI: 10.1104/pp.110.161968] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The highly resistant biopolymer, sporopollenin, gives the outer wall (exine) of spores and pollen grains their unparalleled strength, shielding these structures from terrestrial stresses. Despite a limited understanding of the composition of sporopollenin, it appears that the synthesis of sporopollenin occurs in the tapetum and requires the transport of one or more sporopollenin constituents to the surface of developing microspores. Here, we describe ABCG26, a member of the ATP-binding cassette (ABC) transporter superfamily, which is required for pollen exine formation in Arabidopsis (Arabidopsis thaliana). abcg26 mutants are severely reduced in fertility, with most siliques failing to produce seeds by self-fertilization and mature anthers failing to release pollen. Transmission electron microscopy analyses revealed an absence of an exine wall on abcg26-1 mutant microspores. Phenotypic abnormalities in pollen wall formation were first apparent in early uninucleate microspores as a lack of exine formation and sporopollenin deposition. Additionally, the highest levels of ABCG26 mRNA were in the tapetum, during early pollen wall formation, sporopollenin biosynthesis, and sporopollenin deposition. Accumulations resembling the trilamellar lipidic coils in the abcg11 and abcg12 mutants defective in cuticular wax export were observed in the anther locules of abcg26 mutants. A yellow fluorescent protein-ABCG26 protein was localized to the endoplasmic reticulum and plasma membrane. Our results show that ABCG26 plays a critical role in exine formation and pollen development and are consistent with a model by which ABCG26 transports sporopollenin precursors across the tapetum plasma membrane into the locule for polymerization on developing microspore walls.
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Kulich I, Cole R, Drdová E, Cvrcková F, Soukup A, Fowler J, Zárský V. Arabidopsis exocyst subunits SEC8 and EXO70A1 and exocyst interactor ROH1 are involved in the localized deposition of seed coat pectin. THE NEW PHYTOLOGIST 2010; 188:615-25. [PMID: 20618910 DOI: 10.1111/j.1469-8137.2010.03372.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
• Polarized deposition of cell wall pectins is a key process in Arabidopsis thaliana myxospermous seed coat development. The exocyst, an octameric secretory vesicle tethering complex, has recently been shown to be involved in the regulation of cell polarity in plants. Here, we used the Arabidopsis seed coat to study the participation of the exocyst complex in polarized pectin delivery. • We characterized the amount of pectinaceous mucilage and seed coat structure in sec8 and exo70A1 exocyst mutants. Using a yeast two-hybrid screen, we identified a new interactor of the exocyst subunit Exo70A1, termed Roh1, a member of the DUF793 protein family. • T-DNA insertions in SEC8, EXO70A1 caused considerable deviations from normal seed coat development, in particular reduced pectin deposition and defects in the formation of the central columella of seed epidermal cells. A gain-of-function mutation of ROH1 also caused reduced pectin deposition. Interestingly, we observed a systematic difference in seed coat development between primary and secondary inflorescences in wild-type plants: siliques from secondary branches produced seeds with thicker seed coats. • The participation of exocyst subunits in mucilage deposition provides direct evidence for the role of the exocyst in polarized cell wall morphogenesis.
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Affiliation(s)
- Ivan Kulich
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Prague, Czech Republic
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McFarlane HE, Shin JJ, Bird DA, Samuels AL. Arabidopsis ABCG transporters, which are required for export of diverse cuticular lipids, dimerize in different combinations. THE PLANT CELL 2010; 22:3066-75. [PMID: 20870961 PMCID: PMC2965547 DOI: 10.1105/tpc.110.077974] [Citation(s) in RCA: 190] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 08/27/2010] [Accepted: 09/03/2010] [Indexed: 05/18/2023]
Abstract
ATP binding cassette (ABC) transporters play diverse roles, including lipid transport, in all kingdoms. ABCG subfamily transporters that are encoded as half-transporters require dimerization to form a functional ABC transporter. Different dimer combinations that may transport diverse substrates have been predicted from mutant phenotypes. In Arabidopsis thaliana, mutant analyses have shown that ABCG11/WBC11 and ABCG12/CER5 are required for lipid export from the epidermis to the protective cuticle. The objective of this study was to determine whether ABCG11 and ABCG12 interact with themselves or each other using bimolecular fluorescence complementation (BiFC) and protein traffic assays in vivo. With BiFC, ABCG11/ABCG12 heterodimers and ABCG11 homodimers were detected, while ABCG12 homodimers were not. Fluorescently tagged ABCG11 or ABCG12 was localized in the stem epidermal cells of abcg11 abcg12 double mutants. ABCG11 could traffic to the plasma membrane in the absence of ABCG12, suggesting that ABCG11 is capable of forming flexible dimer partnerships. By contrast, ABCG12 was retained in the endoplasmic reticulum in the absence of ABCG11, indicating that ABCG12 is only capable of forming a dimer with ABCG11 in epidermal cells. Emerging themes in ABCG transporter biology are that some ABCG proteins are promiscuous, having multiple partnerships, while other ABCG transporters form obligate heterodimers for specialized functions.
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Affiliation(s)
- Heather E. McFarlane
- Department of Botany, University of British Columbia, Vancouver, Canada, V6T 1Z4
| | - John J.H. Shin
- Department of Botany, University of British Columbia, Vancouver, Canada, V6T 1Z4
| | | | - A. Lacey Samuels
- Department of Botany, University of British Columbia, Vancouver, Canada, V6T 1Z4
- Address correspondence to
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Arsovski AA, Haughn GW, Western TL. Seed coat mucilage cells of Arabidopsis thaliana as a model for plant cell wall research. PLANT SIGNALING & BEHAVIOR 2010; 5:796-801. [PMID: 20505351 PMCID: PMC3014532 DOI: 10.4161/psb.5.7.11773] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 03/10/2010] [Indexed: 05/17/2023]
Abstract
Plant cells are encased within a complex polysaccharide wall that strengthens the cell and has key roles in all aspects of plant cell growth, differentiation, and interaction with the environment. This dynamic structure is under continual modification during plant development, and its synthesis and modification require the activity of a myriad of enzymes. The mucilage secretory cells (MSCs) of the Arabidopsis thaliana seed coat provide a model for the discovery of novel genes involved in the synthesis, secretion and modification of cell wall components, particularly pectin. These cells synthesize copious amounts of pectinaceous mucilage during development and, upon hydration of the desiccated seed, the mucilage rapidly swells, bursts from the MSCs and surrounds the seed in a gelatinous capsule. Several genes affecting MSC differentiation, pectin synthesis, and mucilage release have been identified and additional genes involved in these and related processes including pectin secretion and the mechanical alteration of cell walls await to be discovered.
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Arabidopsis cortical microtubules position cellulose synthase delivery to the plasma membrane and interact with cellulose synthase trafficking compartments. Nat Cell Biol 2009; 11:797-806. [PMID: 19525940 DOI: 10.1038/ncb1886] [Citation(s) in RCA: 458] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 05/20/2009] [Indexed: 01/10/2023]
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Crowell EF, Bischoff V, Desprez T, Rolland A, Stierhof YD, Schumacher K, Gonneau M, Höfte H, Vernhettes S. Pausing of Golgi bodies on microtubules regulates secretion of cellulose synthase complexes in Arabidopsis. THE PLANT CELL 2009; 21:1141-54. [PMID: 19376932 PMCID: PMC2685615 DOI: 10.1105/tpc.108.065334] [Citation(s) in RCA: 355] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Plant growth and organ formation depend on the oriented deposition of load-bearing cellulose microfibrils in the cell wall. Cellulose is synthesized by plasma membrane-bound complexes containing cellulose synthase proteins (CESAs). Here, we establish a role for the cytoskeleton in intracellular trafficking of cellulose synthase complexes (CSCs) through the in vivo study of the green fluorescent protein (GFP)-CESA3 fusion protein in Arabidopsis thaliana hypocotyls. GFP-CESA3 localizes to the plasma membrane, Golgi apparatus, a compartment identified by the VHA-a1 marker, and, surprisingly, a novel microtubule-associated cellulose synthase compartment (MASC) whose formation and movement depend on the dynamic cortical microtubule array. Osmotic stress or treatment with the cellulose synthesis inhibitor CGA 325'615 induces internalization of CSCs in MASCs, mimicking the intracellular distribution of CSCs in nongrowing cells. Our results indicate that cellulose synthesis is coordinated with growth status and regulated in part through CSC internalization. We find that CSC insertion in the plasma membrane is regulated by pauses of the Golgi apparatus along cortical microtubules. Our data support a model in which cortical microtubules not only guide the trajectories of CSCs in the plasma membrane, but also regulate the insertion and internalization of CSCs, thus allowing dynamic remodeling of CSC secretion during cell expansion and differentiation.
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Affiliation(s)
- Elizabeth Faris Crowell
- Laboratoire de Biologie Cellulaire, Institut National de la Recherche Agronomique, 78026 Versailles cedex, France
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Arsovski AA, Villota MM, Rowland O, Subramaniam R, Western TL. MUM ENHANCERS are important for seed coat mucilage production and mucilage secretory cell differentiation in Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:2601-12. [PMID: 19401413 PMCID: PMC2692007 DOI: 10.1093/jxb/erp102] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 02/20/2009] [Accepted: 03/11/2009] [Indexed: 05/17/2023]
Abstract
Pollination triggers not only embryo development but also the differentiation of the ovule integuments to form a specialized seed coat. The mucilage secretory cells of the Arabidopsis thaliana seed coat undergo a complex differentiation process in which cell growth is followed by the synthesis and secretion of pectinaceous mucilage. A number of genes have been identified affecting mucilage secretory cell differentiation, including MUCILAGE-MODIFIED4 (MUM4). mum4 mutants produce a reduced amount of mucilage and cloning of MUM4 revealed that it encodes a UDP-L-rhamnose synthase that is developmentally up-regulated to provide rhamnose for mucilage pectin synthesis. To identify additional genes acting in mucilage synthesis and secretion, a screen for enhancers of the mum4 phenotype was performed. Eight mum enhancers (men) have been identified, two of which result from defects in known mucilage secretory cell genes (MUM2 and MYB61). Our results show that, in a mum4 background, mutations in MEN1, MEN4, and MEN5 lead to further reductions in mucilage compared to mum4 single mutants, suggesting that they are involved in mucilage synthesis or secretion. Conversely, mutations in MEN2 and MEN6 appear to affect mucilage release rather than quantity. With the exception of men4, whose single mutant exhibits reduced mucilage, none of these genes have a single mutant phenotype, suggesting that they would not have been identified outside the compromised mum4 background.
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Affiliation(s)
| | - Maria M. Villota
- Department of Biology, Carleton University, Ottawa, ON, Canada K1S 5B6
- Agriculture and Agri-Food Canada, Eastern Cereal and Oilseed Research Centre, Ottawa, ON, Canada K1A 0C6
| | - Owen Rowland
- Department of Biology, Carleton University, Ottawa, ON, Canada K1S 5B6
| | - Rajagopal Subramaniam
- Agriculture and Agri-Food Canada, Eastern Cereal and Oilseed Research Centre, Ottawa, ON, Canada K1A 0C6
| | - Tamara L. Western
- Department of Biology, McGill University, Montreal, QC, Canada H3A 1B1
- To whom correspondence should be addressed: E-mail:
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Žárský V, Cvrčková F, Potocký M, Hála M. Exocytosis and cell polarity in plants - exocyst and recycling domains. THE NEW PHYTOLOGIST 2009; 183:255-272. [PMID: 19496948 DOI: 10.1111/j.1469-8137.2009.02880.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
In plants, exocytosis is a central mechanism of cell morphogenesis. We still know surprisingly little about some aspects of this process, starting with exocytotic vesicle formation, which may take place at the trans-Golgi network even without coat assistance, facilitated by the local regulation of membrane lipid organization. The RabA4b guanosine triphosphatase (GTPase), recruiting phosphatidylinositol-4-kinase to the trans-Golgi network, is a candidate vesicle formation organizer. However, in plant cells, there are obviously additional endosomal source compartments for secretory vesicles. The Rho/Rop GTPase regulatory module is central for the initiation of exocytotically active domains in plant cell cortex (activated cortical domains). Most plant cells exhibit several distinct plasma membrane domains, established and maintained by endocytosis-driven membrane recycling. We propose the concept of a 'recycling domain', uniting the activated cortical domain and the connected endosomal compartments, as a dynamic spatiotemporal entity. We have recently described the exocyst tethering complex in plant cells. As a result of the multiplicity of its putative Exo70 subunits, this complex may belong to core regulators of recycling domain organization, including the generation of multiple recycling domains within a single cell. The conventional textbook concept that the plant secretory pathway is largely constitutive is misleading.
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Affiliation(s)
- Viktor Žárský
- Department of Plant Physiology, Charles University, Viničná 5, 128 44 Praha 2, Czech Republic
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Fatima Cvrčková
- Department of Plant Physiology, Charles University, Viničná 5, 128 44 Praha 2, Czech Republic
| | - Martin Potocký
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Michal Hála
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02 Praha 6, Czech Republic
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Young RE, McFarlane HE, Hahn MG, Western TL, Haughn GW, Samuels AL. Analysis of the Golgi apparatus in Arabidopsis seed coat cells during polarized secretion of pectin-rich mucilage. THE PLANT CELL 2008; 20:1623-38. [PMID: 18523060 PMCID: PMC2483359 DOI: 10.1105/tpc.108.058842] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 04/05/2008] [Accepted: 05/16/2008] [Indexed: 05/17/2023]
Abstract
Differentiation of the Arabidopsis thaliana seed coat cells includes a secretory phase where large amounts of pectinaceous mucilage are deposited to a specific domain of the cell wall. During this phase, Golgi stacks had cisternae with swollen margins and trans-Golgi networks consisting of interconnected vesicular clusters. The proportion of Golgi stacks producing mucilage was determined by immunogold labeling and transmission electron microscopy using an antimucilage antibody, CCRC-M36. The large percentage of stacks found to contain mucilage supports a model where all Golgi stacks produce mucilage synchronously, rather than having a subset of specialist Golgi producing pectin product. Initiation of mucilage biosynthesis was also correlated with an increase in the number of Golgi stacks per cell. Interestingly, though the morphology of individual Golgi stacks was dependent on the volume of mucilage produced, the number was not, suggesting that proliferation of Golgi stacks is developmentally programmed. Mapping the position of mucilage-producing Golgi stacks within developing seed coat cells and live-cell imaging of cells labeled with a trans-Golgi marker showed that stacks were randomly distributed throughout the cytoplasm rather than clustered at the site of secretion. These data indicate that the destination of cargo has little effect on the location of the Golgi stack within the cell.
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Affiliation(s)
- Robin E Young
- Department of Botany, University of British Columbia, Vancouver, Canada V6T 1Z4
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