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Tsang I, Atkinson JA, Rawsthorne S, Cockram J, Leigh F. Root hairs: an underexplored target for sustainable cereal crop production. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:5484-5500. [PMID: 38894654 PMCID: PMC11427827 DOI: 10.1093/jxb/erae275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 06/17/2024] [Indexed: 06/21/2024]
Abstract
To meet the demands of a rising human population, plant breeders will need to develop improved crop varieties that maximize yield in the face of increasing pressure on crop production. Historically, the optimization of crop root architecture has represented a challenging breeding target due to the inaccessibility of the root systems. Root hairs, single cell projections from the root epidermis, are perhaps the most overlooked component of root architecture traits. Root hairs play a central role in facilitating water, nutrient uptake, and soil cohesion. Current root hair architectures may be suboptimal under future agricultural production regimes, coupled with an increasingly variable climate. Here, we review the genetic control of root hair development in the world's three most important crops-rice, maize, and wheat-and highlight conservation of gene function between monocots and the model dicot species Arabidopsis. Advances in genomic techniques including gene editing combined with traditional plant breeding methods have the potential to overcome many inherent issues associated with the design of improved root hair architectures. Ultimately, this will enable detailed characterization of the effects of contrasting root hair morphology strategies on crop yield and resilience, and the development of new varieties better adapted to deliver future food security.
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Affiliation(s)
- Ian Tsang
- NIAB, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
- University of Nottingham, Plant Sciences Building, Sutton Bonnington Campus, Nottingham LE12 5RD, UK
| | - Jonathan A Atkinson
- University of Nottingham, Plant Sciences Building, Sutton Bonnington Campus, Nottingham LE12 5RD, UK
| | - Stephen Rawsthorne
- The Morley Agricultural Foundation, Morley Business Centre, Deopham Road, Morley St Botolph, Wymondham NR18 9DF, UK
| | - James Cockram
- NIAB, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Fiona Leigh
- NIAB, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
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2
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Zheng T, Zhou Q, Tao Z, Ouyang S. Magnetic iron-based nanoparticles biogeochemical behavior in soil-plant system: A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166643. [PMID: 37647959 DOI: 10.1016/j.scitotenv.2023.166643] [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: 02/24/2023] [Revised: 07/31/2023] [Accepted: 08/26/2023] [Indexed: 09/01/2023]
Abstract
Increasing attention is being given to magnetic iron-based nanoparticles (MINPs) because of their potential environmental benefits. Owing to the earth abundance and high utilization of MINPs, as well as the significant functions of Fe in sustainable agriculture and environmental remediation, an understanding of the environmental fate of MINPs is indispensable. However, there are still knowledge gaps regarding the largely unknown environmental behaviors and fate of MINPs in soil-plant system. Thus, this review summarizes recent literature on the biogeochemical behavior (uptake, transportation, and transformation) of MINPs in soil and plants. The different possible uptake (e.g., foliar and root adsorption) and translocation (e.g., xylem, phloem, symplastic/apoplastic pathway, and endocytosis) pathways are discussed. Furthermore, drivers of MINPs uptake and transportation (e.g., soil characteristics, fertilizer treatments, copresence of inorganic and organic anions, meteorological conditions, and cell wall pores) in both soil and plant environments are summarized. This review also details the physical, chemical, and biological transformations of MINPs in soil-plant system. More importantly, a metadata analysis from the existing literature was employed to investigate the distinction between MINPs and other engineering nanoparticles biogeochemical behavior. In the future, more attention should be given to understanding the behavior of MINPs in soil-plant system and improving the capabilities of predictive models. This review thus highlights the main knowledge gaps regarding MINPs behavior and fate to provide guidance for their safe application in agrochemicals, crop production, and soil health.
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Affiliation(s)
- Tong Zheng
- College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Carbon Neutrality Interdisciplinary Science Center, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Qixing Zhou
- College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Carbon Neutrality Interdisciplinary Science Center, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Zongxin Tao
- College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Carbon Neutrality Interdisciplinary Science Center, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Shaohu Ouyang
- College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Carbon Neutrality Interdisciplinary Science Center, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
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Chen J, Guo Y, Zhang X, Liu J, Gong P, Su Z, Fan L, Li G. Emerging Nanoparticles in Food: Sources, Application, and Safety. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3564-3582. [PMID: 36791411 DOI: 10.1021/acs.jafc.2c06740] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Nanoparticles (NPs) are small-sized, with high surface activity and antibacterial and antioxidant properties. As a result, some NPs are used as functional ingredients in food additives, food packaging materials, nutrient delivery, nanopesticides, animal feeds, and fertilizers to improve the bioavailability, quality, and performance complement or upgrade. However, the widespread use of NPs in the industry increases the exposure risk of NPs to humans due to their migration from the environment to food. Nevertheless, some NPs, such as carbon dots, NPs found in various thermally processed foods, are also naturally produced from the food during food processing. Given their excellent ability to penetrate biopermeable barriers, the potential safety hazards of NPs on human health have attracted increased attention. Herein, three emerging NPs are introduced including carbon-based NPs (e.g., CNTs), nanoselenium NPs (SeNPs), and rare earth oxide NPs (e.g., CeO2 NPs). In addition, their applications in the food industry, absorption pathways into the human body, and potential risk mechanisms are discussed. Challenges and prospects for the use of NPs in food are also proposed.
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Affiliation(s)
- Jian Chen
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Yuxi Guo
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Xianlong Zhang
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Jianghua Liu
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Pin Gong
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Zhuoqun Su
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Lihua Fan
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
| | - Guoliang Li
- School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021 People's Republic of China
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Stéger A, Palmgren M. Root hair growth from the pH point of view. FRONTIERS IN PLANT SCIENCE 2022; 13:949672. [PMID: 35968128 PMCID: PMC9363702 DOI: 10.3389/fpls.2022.949672] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 07/07/2022] [Indexed: 05/06/2023]
Abstract
Root hairs are tubular outgrowths of epidermal cells that increase the root surface area and thereby make the root more efficient at absorbing water and nutrients. Their expansion is limited to the root hair apex, where growth is reported to take place in a pulsating manner. These growth pulses coincide with oscillations of the apoplastic and cytosolic pH in a similar way as has been reported for pollen tubes. Likewise, the concentrations of apoplastic reactive oxygen species (ROS) and cytoplasmic Ca2+ oscillate with the same periodicity as growth. Whereas ROS appear to control cell wall extensibility and opening of Ca2+ channels, the role of protons as a growth signal in root hairs is less clear and may differ from that in pollen tubes where plasma membrane H+-ATPases have been shown to sustain growth. In this review, we outline our current understanding of how pH contributes to root hair development.
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Gajek K, Janiak A, Korotko U, Chmielewska B, Marzec M, Szarejko I. Whole Exome Sequencing-Based Identification of a Novel Gene Involved in Root Hair Development in Barley ( Hordeum vulgare L.). Int J Mol Sci 2021; 22:ijms222413411. [PMID: 34948205 PMCID: PMC8709170 DOI: 10.3390/ijms222413411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/26/2021] [Accepted: 12/09/2021] [Indexed: 12/30/2022] Open
Abstract
Root hairs play a crucial role in anchoring plants in soil, interaction with microorganisms and nutrient uptake from the rhizosphere. In contrast to Arabidopsis, there is a limited knowledge of root hair morphogenesis in monocots, including barley (Hordeum vulgare L.). We have isolated barley mutant rhp1.e with an abnormal root hair phenotype after chemical mutagenesis of spring cultivar ‘Sebastian’. The development of root hairs was initiated in the mutant but inhibited at the very early stage of tip growth. The length of root hairs reached only 3% of the length of parent cultivar. Using a whole exome sequencing (WES) approach, we identified G1674A mutation in the HORVU1Hr1G077230 gene, located on chromosome 1HL and encoding a cellulose synthase-like C1 protein (HvCSLC1) that might be involved in the xyloglucan (XyG) synthesis in root hairs. The identified mutation led to the retention of the second intron and premature termination of the HvCSLC1 protein. The mutation co-segregated with the abnormal root hair phenotype in the F2 progeny of rhp1.e mutant and its wild-type parent. Additionally, different substitutions in HORVU1Hr1G077230 were found in four other allelic mutants with the same root hair phenotype. Here, we discuss the putative role of HvCSLC1 protein in root hair tube elongation in barley.
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Affiliation(s)
- Katarzyna Gajek
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, 40-032 Katowice, Poland; (K.G.); (A.J.); (B.C.); (M.M.)
| | - Agnieszka Janiak
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, 40-032 Katowice, Poland; (K.G.); (A.J.); (B.C.); (M.M.)
| | - Urszula Korotko
- Centre for Bioinformatics and Data Analysis, Medical University of Bialystok, 15-089 Bialystok, Poland;
| | - Beata Chmielewska
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, 40-032 Katowice, Poland; (K.G.); (A.J.); (B.C.); (M.M.)
| | - Marek Marzec
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, 40-032 Katowice, Poland; (K.G.); (A.J.); (B.C.); (M.M.)
| | - Iwona Szarejko
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, 40-032 Katowice, Poland; (K.G.); (A.J.); (B.C.); (M.M.)
- Correspondence:
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Cheong MS, Lee DY, Seo KH, Choi GH, Song YH, Park KH, Kim JH. Phenylephrine, a small molecule, inhibits pectin methylesterases. Biochem Biophys Res Commun 2019; 508:320-325. [DOI: 10.1016/j.bbrc.2018.11.117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 11/19/2018] [Indexed: 11/25/2022]
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7
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Hu H, Zhang R, Dong S, Li Y, Fan C, Wang Y, Xia T, Chen P, Wang L, Feng S, Persson S, Peng L. AtCSLD3 and GhCSLD3 mediate root growth and cell elongation downstream of the ethylene response pathway in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1065-1080. [PMID: 29253184 PMCID: PMC6018909 DOI: 10.1093/jxb/erx470] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 12/04/2017] [Indexed: 05/12/2023]
Abstract
CSLD3, a gene of the cellulose synthase-like D family, affects root hair elongation, but its interactions with ethylene signaling and phosphate-starvation are poorly understood. Here, we aim to understand the role of CSLD3 in the context of the ethylene signaling and phosphate starvation pathways in Arabidopsis plant growth. Therefore, we performed a comparative analysis of the csld3-1 mutant, CSLD3-overexpressing lines, and ethylene-response mutants, such as the constitutive ethylene-response mutant i-ctr1. We found that CSLD3 overexpression enhanced root and hypocotyl growth by increasing cell elongation, and that the root growth was highly sensitive to ethylene treatment (1 µM ACC), in particular under phosphate starvation. However, the CSLD3-mediated hypocotyl elongation occurred independently of the ethylene signaling pathway. Notably, the typical induction of root hair and root elongation by ethylene and phosphate-starvation was completely abolished in the csld3-1 mutant. Furthermore, i-ctr1 csld3-1 double-mutants were hairless like the csld3-1 parent, confirming that CSLD3 acts downstream of the ethylene signaling pathway during root growth. Moreover, the CSLD3 levels positively correlated with cellulose levels, indicating a role of CSLD3 in cellulose synthesis, which may explain the observed growth effects. Our results establish how CSLD3 works in the context of the ethylene signaling and phosphate-starvation pathways during root hair growth, cell elongation, and cell wall biosynthesis.
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Affiliation(s)
- Huizhen Hu
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Ran Zhang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Shuchao Dong
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Ying Li
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Chunfen Fan
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Yanting Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Tao Xia
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Life Science and Technology, Huazhong Agricultural University, China
| | - Peng Chen
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Lingqiang Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Shengqiu Feng
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
| | - Staffan Persson
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
- School of Biosciences, University of Melbourne, Australia
| | - Liangcai Peng
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, China
- College of Plant Science and Technology, Huazhong Agricultural University, China
- Correspondence:
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MacAlister CA, Ortiz-Ramírez C, Becker JD, Feijó JA, Lippman ZB. Hydroxyproline O-arabinosyltransferase mutants oppositely alter tip growth in Arabidopsis thaliana and Physcomitrella patens. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 85:193-208. [PMID: 26577059 PMCID: PMC4738400 DOI: 10.1111/tpj.13079] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/17/2015] [Accepted: 11/03/2015] [Indexed: 05/20/2023]
Abstract
Hydroxyproline O-arabinosyltransferases (HPATs) are members of a small, deeply conserved family of plant-specific glycosyltransferases that add arabinose sugars to diverse proteins including cell wall-associated extensins and small signaling peptides. Recent genetic studies in flowering plants suggest that different HPAT homologs have been co-opted to function in diverse species-specific developmental contexts. However, nothing is known about the roles of HPATs in basal plants. We show that complete loss of HPAT function in Arabidopsis thaliana and the moss Physcomitrella patens results in a shared defect in gametophytic tip cell growth. Arabidopsis hpat1/2/3 triple knockout mutants suffer from a strong male sterility defect as a consequence of pollen tubes that fail to fully elongate following pollination. Knocking out the two HPAT genes of Physcomitrella results in larger multicellular filamentous networks due to increased elongation of protonemal tip cells. Physcomitrella hpat mutants lack cell-wall associated hydroxyproline arabinosides and can be rescued with exogenous cellulose, while global expression profiling shows that cell wall-associated genes are severely misexpressed, implicating a defect in cell wall formation during tip growth. Our findings point to a major role for HPATs in influencing cell elongation during tip growth in plants.
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Affiliation(s)
| | | | - Jörg D Becker
- Instituto Gulbenkian de Ciência, P-2780-156, Oeiras, Portugal
| | - José A Feijó
- Instituto Gulbenkian de Ciência, P-2780-156, Oeiras, Portugal
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742-5815, USA
| | - Zachary B Lippman
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11746, USA
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11746, USA
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9
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Schwab F, Zhai G, Kern M, Turner A, Schnoor JL, Wiesner MR. Barriers, pathways and processes for uptake, translocation and accumulation of nanomaterials in plants – Critical review. Nanotoxicology 2015; 10:257-78. [DOI: 10.3109/17435390.2015.1048326] [Citation(s) in RCA: 350] [Impact Index Per Article: 38.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Fabienne Schwab
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, USA,
- Center for the Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, NC, USA, and
| | - Guangshu Zhai
- Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, IA, USA
| | - Meaghan Kern
- Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, IA, USA
| | - Amalia Turner
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, USA,
- Center for the Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, NC, USA, and
| | - Jerald L. Schnoor
- Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, IA, USA
| | - Mark R. Wiesner
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, USA,
- Center for the Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, NC, USA, and
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10
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Larson ER, Tierney ML, Tinaz B, Domozych DS. Using monoclonal antibodies to label living root hairs: a novel tool for studying cell wall microarchitecture and dynamics in Arabidopsis. PLANT METHODS 2014; 10:30. [PMID: 25309618 PMCID: PMC4192329 DOI: 10.1186/1746-4811-10-30] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 09/23/2014] [Indexed: 05/06/2023]
Abstract
BACKGROUND The Arabidopsis root hair represents a valuable cell model for elucidating polar expansion mechanisms in plant cells and the overall biology of roots. The deposition and development of the cell wall is central to the root hair expansion apparatus. During this process, incorporation of specific wall polymers into the growing wall architecture constitutes a critical spatio-temporal event that controls hair size and growth rate and one that is closely coordinated with the cell's endomembrane, cytoskeletal and signal transduction apparatuses. RESULTS In this study, the protocol for live cell labeling of roots with monoclonal antibodies that bind to specific wall polymers is presented. This method allows for rapid assessment of root hair cell wall composition during development and assists in describing changes to cell wall composition in transgenic mutant lines. Enzymatic "unmasking" of specific polymers prior to labeling allows for refined interpretation of cell wall chemistry. Live cell immunofluorescence data may also be correlated with transmission electron microscopy-based immunogold labeling. CONCLUSIONS Live Arabidopsis root hairs may be labeled with cell wall polymer-specific antibodies. This methodology allows for direct visualization of cell wall dynamics throughout development in stable transgenic plant lines. It also provides an important new tool in the elucidation of the specific interactions occurring between membrane trafficking networks, cytoskeleton and the cell wall deposition/remodeling mechanism.
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Affiliation(s)
- Emily R Larson
- />Cellular, Molecular, and Biomedical Science Program, University of Vermont, Burlington, VT USA
- />Laboratory of Plant Physiology and Biophysics, Institute of Molecular Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow, G12 8QQ UK
| | - Mary L Tierney
- />Cellular, Molecular, and Biomedical Science Program, University of Vermont, Burlington, VT USA
- />Department of Plant Biology, University of Vermont, Burlington, VT USA
| | - Berke Tinaz
- />Department of Biology, Skidmore College, Saratoga Springs, NY USA
| | - David S Domozych
- />Department of Biology, Skidmore College, Saratoga Springs, NY USA
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11
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Sanati Nezhad A, Geitmann A. The cellular mechanics of an invasive lifestyle. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:4709-28. [PMID: 24014865 DOI: 10.1093/jxb/ert254] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Invasive behaviour is the hallmark of a variety of cell types of animal, plant, and fungal origin. Here we review the purpose and mechanism of invasive growth and migration. The focus is on the physical principles governing the process, the source of invasive force, and the cellular mechanism by which the cell penetrates the substrate. The current experimental methods for measuring invasive force and the modelling approaches for studying invasive behaviour are explained, and future experimental strategies are proposed.
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Affiliation(s)
- Amir Sanati Nezhad
- McGill University and Génome Québec Innovation Centre, Biomedical Engineering Department, McGill University, Montreal, Canada
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12
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Qi G, Hu R, Yu L, Chai G, Cao Y, Zuo R, Kong Y, Zhou G. Two poplar cellulose synthase-like D genes, PdCSLD5 and PdCSLD6, are functionally conserved with Arabidopsis CSLD3. JOURNAL OF PLANT PHYSIOLOGY 2013; 170:1267-1276. [PMID: 23746994 DOI: 10.1016/j.jplph.2013.04.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 04/01/2013] [Accepted: 04/07/2013] [Indexed: 06/02/2023]
Abstract
Root hairs are tip-growing long tubular outgrowths of specialized epidermal cells, and are important for nutrient and water uptake and interaction with the soil microflora. Here we characterized two poplar cellulose synthase-like D (CSLD) genes, PdCSLD5 and PdCSLD6, the most probable orthologs to the Arabidopsis AtCSLD3/KOJAK gene. Both PdCSLD5 and PdCSLD6 are strongly expressed in roots, including in the root hairs. Subcellular localization experiments showed that these two proteins are located not only in the polarized plasma membrane of root hair tips, but also in Golgi apparatus of the root hair and non-hair-forming cells. Overexpression of these two poplar genes in the atcsld3 mutant was able to rescue most of the defects caused by disruption of AtCSLD3, including root hair morphological changes, altered cell wall monosaccharide composition, increased non-crystalline β-1,4-glucan and decreased crystalline cellulose contents. Taken together, our results provide evidence indicating that PdCSLD5 and PdCSLD6 are functionally conserved with AtCSLD3 and support a role for PdCSLD5 and PdCSL6 specifically in crystalline cellulose production in poplar root hair tips. The results presented here also suggest that at least part of the mechanism of root hair formation is conserved between herbaceous and woody plants.
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Affiliation(s)
- Guang Qi
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, PR China
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13
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Nguyen THN, Brechenmacher L, Aldrich JT, Clauss TR, Gritsenko MA, Hixson KK, Libault M, Tanaka K, Yang F, Yao Q, Paša-Tolić L, Xu D, Nguyen HT, Stacey G. Quantitative phosphoproteomic analysis of soybean root hairs inoculated with Bradyrhizobium japonicum. Mol Cell Proteomics 2012; 11:1140-55. [PMID: 22843990 PMCID: PMC3494206 DOI: 10.1074/mcp.m112.018028] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 06/05/2012] [Indexed: 11/06/2022] Open
Abstract
Root hairs are single hair-forming cells on roots that function to increase root surface area, enhancing water and nutrient uptake. In leguminous plants, root hairs also play a critical role as the site of infection by symbiotic nitrogen fixing rhizobia, leading to the formation of a novel organ, the nodule. The initial steps in the rhizobia-root hair infection process are known to involve specific receptor kinases and subsequent kinase cascades. Here, we characterize the phosphoproteome of the root hairs and the corresponding stripped roots (i.e. roots from which root hairs were removed) during rhizobial colonization and infection to gain insight into the molecular mechanism of root hair cell biology. We chose soybean (Glycine max L.), one of the most important crop plants in the legume family, for this study because of its larger root size, which permits isolation of sufficient root hair material for phosphoproteomic analysis. Phosphopeptides derived from root hairs and stripped roots, mock inoculated or inoculated with the soybean-specific rhizobium Bradyrhizobium japonicum, were labeled with the isobaric tag eight-plex iTRAQ, enriched using Ni-NTA magnetic beads and subjected to nanoRPLC-MS/MS1 analysis using HCD and decision tree guided CID/ETD strategy. A total of 1625 unique phosphopeptides, spanning 1659 nonredundant phosphorylation sites, were detected from 1126 soybean phosphoproteins. Among them, 273 phosphopeptides corresponding to 240 phosphoproteins were found to be significantly regulated (>1.5-fold abundance change) in response to inoculation with B. japonicum. The data reveal unique features of the soybean root hair phosphoproteome, including root hair and stripped root-specific phosphorylation suggesting a complex network of kinase-substrate and phosphatase-substrate interactions in response to rhizobial inoculation.
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Affiliation(s)
- Tran Hong Nha Nguyen
- From the ‡Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
- §National Center for Soybean Biotechnology, University of Missouri, Columbia, Missouri 65211
- ¶Vietnam Education Foundation
| | - Laurent Brechenmacher
- From the ‡Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
- §National Center for Soybean Biotechnology, University of Missouri, Columbia, Missouri 65211
| | - Joshua T. Aldrich
- ‖Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Therese R. Clauss
- **Fundamental and Computational Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Marina A. Gritsenko
- **Fundamental and Computational Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Kim K. Hixson
- ‖Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Marc Libault
- ‡‡Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma 73019
| | - Kiwamu Tanaka
- From the ‡Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
- §National Center for Soybean Biotechnology, University of Missouri, Columbia, Missouri 65211
| | - Feng Yang
- **Fundamental and Computational Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Qiuming Yao
- §§Department of Computer Science, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
| | - Ljiljana Paša-Tolić
- ‖Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Dong Xu
- §§Department of Computer Science, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
| | - Henry T. Nguyen
- From the ‡Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
- §National Center for Soybean Biotechnology, University of Missouri, Columbia, Missouri 65211
| | - Gary Stacey
- From the ‡Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211
- §National Center for Soybean Biotechnology, University of Missouri, Columbia, Missouri 65211
- ¶¶Division of Biochemistry, University of Missouri, Columbia, Missouri 65211
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14
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Handford M, Rodríguez-Furlán C, Marchant L, Segura M, Gómez D, Alvarez-Buylla E, Xiong GY, Pauly M, Orellana A. Arabidopsis thaliana AtUTr7 encodes a golgi-localized UDP-glucose/UDP-galactose transporter that affects lateral root emergence. MOLECULAR PLANT 2012; 5:1263-80. [PMID: 22933714 DOI: 10.1093/mp/sss074] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Nucleotide sugar transporters (NSTs) are antiporters comprising a gene family that plays a fundamental role in the biosynthesis of complex cell wall polysaccharides and glycoproteins in plants. However, due to the limited number of related mutants that have observable phenotypes, the biological function(s) of most NSTs in cell wall biosynthesis and assembly have remained elusive. Here, we report the characterization of AtUTr7 from Arabidopsis (Arabidopsis thaliana (L.) Heynh.), which is homologous to multi-specific UDP-sugar transporters from Drosophila melanogaster, humans, and Caenorhabditis elegans. We show that AtUTr7 possesses the common structural characteristics conserved among NSTs. Using a green fluorescent protein (GFP) tagged version, we demonstrate that AtUTr7 is localized in the Golgi apparatus. We also show that AtUTr7 is widely expressed, especially in the roots and in specific floral organs. Additionally, the results of an in vitro nucleotide sugar transport assay carried out with a tobacco and a yeast expression system suggest that AtUTr7 is capable of transferring UDP-Gal and UDP-Glc, but not a range of other UDP- and GDP-sugars, into the Golgi lumen. Mutants lacking expression of AtUTr7 exhibited an early proliferation of lateral roots as well as distorted root hairs when cultivated at high sucrose concentrations. Furthermore, the distribution of homogalacturonan with a low degree of methyl esterification differed in lateral root tips of the mutant compared to wild-type plants, although additional analytical procedures revealed no further differences in the composition of the root cell walls. This evidence suggests that the transport of UDP-Gal and UDP-Glc into the Golgi under conditions of high root biomass production plays a role in lateral root and root hair development.
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15
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Galway ME, Eng RC, Schiefelbein JW, Wasteneys GO. Root hair-specific disruption of cellulose and xyloglucan in AtCSLD3 mutants, and factors affecting the post-rupture resumption of mutant root hair growth. PLANTA 2011; 233:985-99. [PMID: 21279381 DOI: 10.1007/s00425-011-1355-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 01/09/2011] [Indexed: 05/10/2023]
Abstract
The glycosyl transferase encoded by the cellulose synthase-like gene CSLD3/KJK/RHD7 (At3g03050) is required for cell wall integrity during root hair formation in Arabidopsis thaliana but it remains unclear whether it contributes to the synthesis of cellulose or hemicellulose. We identified two new alleles, root hair-defective (rhd) 7-1 and rhd7-4, which affect the C-terminal end of the encoded protein. Like root hairs in the previously characterized kjk-2 putative null mutant, rhd7-1 and rhd7-4 hairs rupture before tip growth but, depending on the growth medium and temperature, hairs are able to survive rupture and initiate tip growth, indicating that these alleles retain some function. At 21°C, the rhd7 tip-growing root hairs continued to rupture but at 5ºC, rupture was inhibited, resulting in long, wild type-like root hairs. At both temperatures, the expression of another root hair-specific CSLD gene, CSLD2, was increased in the rhd7-4 mutant but reduced in the kjk-2 mutant, suggesting that CSLD2 expression is CSLD3-dependent, and that CSLD2 could partially compensate for CSLD3 defects to prevent rupture at 5°C. Using a fluorescent brightener (FB 28) to detect cell wall (1 → 4)-β-glucans (primarily cellulose) and CCRC-M1 antibody to detect fucosylated xyloglucans revealed a patchy distribution of both in the mutant root hair cell walls. Cell wall thickness varied, and immunogold electron microscopy indicated that xyloglucan distribution was altered throughout the root hair cell walls. These cell wall defects indicate that CSLD3 is required for the normal organization of both cellulose and xyloglucan in root hair cell walls.
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Affiliation(s)
- Moira E Galway
- Department of Biology, St. Francis Xavier University, PO Box 5000, Antigonish, NS B2G 2W5, Canada.
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16
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Lin C, Choi HS, Cho HT. Root hair-specific EXPANSIN A7 is required for root hair elongation in Arabidopsis. Mol Cells 2011; 31:393-7. [PMID: 21359675 PMCID: PMC3933966 DOI: 10.1007/s10059-011-0046-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 01/17/2011] [Indexed: 10/18/2022] Open
Abstract
Expansins are non-hydrolytic cell wall-loosening proteins that are involved in the cell wall modifications that underlie many plant developmental processes. Root hair growth requires the accumulation of cell wall materials and dynamic cell wall modification at the tip region. Although several lines of indirect evidence support the idea that expansin-mediated wall modification occurs during root hair growth, the involvement of these proteins remains to be demonstrated in vivo. In this study, we used RNA interference (RNAi) to examine the biological function of Arabidopsis thaliana EXPANSIN A7 (AtEXPA7), which is expressed specifically in the root hair cell. The root hairspecific AtEXPA7 promoter was used to drive RNAi expression, which targeted two independent regions in the AtEXPA7 transcript. Quantitative reverse transcriptase-PCR analyses were used to examine AtEXPA7 transcript levels. In four independent RNAi transformant lines, RNAi expression reduced AtEXPA7 transcript levels by 25-58% compared to controls. Accordingly, the root hairs of RNAi transformant lines were 25-48% shorter than control plants and exhibited a broader range of lengths than the controls. Our results provide in vivo evidence that expansins are required for root hair tip growth.
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Affiliation(s)
- Changfa Lin
- Department of Biological Sciences and Genomics and Breeding Institute, Seoul National University, Seoul 151-742, Korea
| | - Hee-Seung Choi
- Department of Biological Sciences and Genomics and Breeding Institute, Seoul National University, Seoul 151-742, Korea
| | - Hyung-Taeg Cho
- Department of Biological Sciences and Genomics and Breeding Institute, Seoul National University, Seoul 151-742, Korea
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17
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Won SK, Choi SB, Kumari S, Cho M, Lee SH, Cho HT. Root hair-specific EXPANSIN B genes have been selected for Graminaceae root hairs. Mol Cells 2010; 30:369-76. [PMID: 20811811 DOI: 10.1007/s10059-010-0127-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Accepted: 07/05/2010] [Indexed: 11/29/2022] Open
Abstract
Cell differentiation ultimately relies on the regulation of cell type-specific genes. For a root hair cell to undergo morphogenesis, diverse cellular processes including cell-wall loosening must occur in a root hair cell-specific manner. Previously, we identified and characterized root hairspecific cis-elements (RHE) from the genes encoding the cell wall-loosening protein EXPANSIN A (EXPA) which functions preferentially on dicot cell walls. This study reports two root hair-specific grass EXPB genes that contain RHEs. These genes are thought to encode proteins that function more efficiently on grass cell walls. The proximal promoter regions of two orthologous EXPB genes from rice (Oryza sativa; OsEXPB5) and barley (Hordeum vulgare; HvEXPB1) included RHE motifs. These promoters could direct root hair-specific expression of green fluorescent protein (GFP) in the roots of rice and Arabidopsis (Arabidopsis thaliana). Promoter deletion analyses demonstrated that the RHE motifs are necessary for root hairspecific expression of these EXPB promoters. Phylogenetic analysis of EXP protein sequences indicated that grass EXPBs are the only orthologs to these root hair-specific EXPBs, separating dicot EXPBs to distal branches of the tree. These results suggest that RHE-containing root hair-specific EXPB genes have evolved for grass-specific cell wall modification during root hair morphogenesis.
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Affiliation(s)
- Su-Kyung Won
- Department of Biological Sciences and Plant Genomics and Breeding Institute, Seoul National University, Seoul, 151-742, Korea
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18
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Melzer B, Steinbrecher T, Seidel R, Kraft O, Schwaiger R, Speck T. The attachment strategy of English ivy: a complex mechanism acting on several hierarchical levels. J R Soc Interface 2010; 7:1383-9. [PMID: 20462880 DOI: 10.1098/rsif.2010.0140] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
English ivy (Hedera helix L.) is able to grow on vertical substrates such as trees, rocks and house plaster, thereby attaching so firmly to the surface that when removed by force typically whole pieces of the climbing substrate are torn off. The structural details of the attachment process are not yet entirely understood. We studied the attachment process of English ivy in detail and suggest a four-phase process to describe the attachment strategy: (i) initial physical contact, (ii) form closure of the root with the substrate, (iii) chemical adhesion, and (iv) shape changes of the root hairs and form-closure with the substrate. These four phases and their variations play an important role in the attachment to differently structured surfaces. We demonstrate that, in English ivy, different mechanisms work together to allow the plant's attachment to various climbing substrates and reveal the importance of micro-fibril orientation in the root hairs for the attachment based on structural changes at the subcellular level.
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Affiliation(s)
- Björn Melzer
- Plant Biomechanics Group AG Speck, Botanic Garden Uni-Freiburg, Schaenzlestrasse 1, 79104 Freiburg, Germany.
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19
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Brechenmacher L, Lee J, Sachdev S, Song Z, Nguyen THN, Joshi T, Oehrle N, Libault M, Mooney B, Xu D, Cooper B, Stacey G. Establishment of a protein reference map for soybean root hair cells. PLANT PHYSIOLOGY 2009; 149:670-82. [PMID: 19036831 PMCID: PMC2633823 DOI: 10.1104/pp.108.131649] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 11/24/2008] [Indexed: 05/19/2023]
Abstract
Root hairs are single tubular cells formed from the differentiation of epidermal cells on roots. They are involved in water and nutrient uptake and represent the infection site on leguminous roots by rhizobia, soil bacteria that establish a nitrogen-fixing symbiosis. Root hairs develop by polar cell expansion or tip growth, a unique mode of plant growth shared only with pollen tubes. A more complete characterization of root hair cell biology will lead to a better understanding of tip growth, the rhizobial infection process, and also lead to improvements in plant water and nutrient uptake. We analyzed the proteome of isolated soybean (Glycine max) root hair cells using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and shotgun proteomics (1D-PAGE-liquid chromatography and multidimensional protein identification technology) approaches. Soybean was selected for this study due to its agronomic importance and its root size. The resulting soybean root hair proteome reference map identified 1,492 different proteins. 2D-PAGE followed by mass spectrometry identified 527 proteins from total cell contents. A complementary shotgun analysis identified 1,134 total proteins, including 443 proteins that were specific to the microsomal fraction. Only 169 proteins were identified by the 2D-PAGE and shotgun methods, which highlights the advantage of using both methods. The proteins identified are involved not only in basic cell metabolism but also in functions more specific to the single root hair cell, including water and nutrient uptake, vesicle trafficking, and hormone and secondary metabolism. The data presented provide useful insight into the metabolic activities of a single, differentiated plant cell type.
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Affiliation(s)
- Laurent Brechenmacher
- National Center for Soybean Biotechnology, Division of Plant Sciences, University of Missouri, Columbia, Missouri 65211, USA
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20
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Macpherson N, Takeda S, Shang Z, Dark A, Mortimer JC, Brownlee C, Dolan L, Davies JM. NADPH oxidase involvement in cellular integrity. PLANTA 2008; 227:1415-8. [PMID: 18317797 DOI: 10.1007/s00425-008-0716-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Accepted: 02/15/2008] [Indexed: 05/06/2023]
Abstract
NADPH oxidase activity is involved in plant adaptation and development. The reactive oxygen species sourced by NADPH oxidase activity may contribute to wall strength and protoplast volume adjustment. Root hair bulge apices of the NADPH oxidase mutant rhd2/Atrbohc were more robust than the kjk cellulose synthase mutant, but burst more readily than the wild type (WT). Root epidermal wall appeared impaired in rhd2/Atrbohc, as revealed by the number of protoplasts released by wall-degrading enzymes. Root hair bulges of rhd2/Atrbohc burst more than the WT when challenged in situ with hypo-osmotic low ionic strength medium. Inhibition of NADPH oxidase activity with diphenylene iodonium caused WT to phenocopy the rhd2/Atrbohc bursting in response to hypo-osmotic shock. This implicates RHD2/AtRBOHC in softening the cell wall to permit protoplast expansion. Overall, the results point to a role for RHD2/AtRBOHC in contributing to wall strength.
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Affiliation(s)
- Neil Macpherson
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
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21
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Kotzer A, Wasteneys G. Mechanisms behind the puzzle: microtubule–microfilament cross-talk in pavement cell formationThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology. ACTA ACUST UNITED AC 2006. [DOI: 10.1139/b06-023] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies are revealing plausible mechanisms that help explain how the two major cytoskeletal systems of plant cells interact to co-ordinate morphogenesis in diffusely expanding cells. In this article, we focus on the development of pavement cells typically found in the leaf epidermis, and highlight work that provides insights into the mechanisms that generate their complex morphology. Pavement cells interdigitate with adjacent cells, forming narrow neck regions interspersed with lobe-like projections. Earlier analysis demonstrated that distinct banding of cortical microtubules and associated accumulation of cell wall material was responsible for maintaining the neck regions during expansion. More recently, it has been determined that patches of fine actin microfilaments regulate the formation of lobing regions. This zonation into microtubule-rich bands and actin patches is coordinated by the activity of Rops, small GTPases that control a wide range of signalling pathways including ones that remodel both actin microfilament and microtubule arrays. Moreover, the formation of microtubule bands and actin patches seems to be self-reinforcing. Loss of microtubule polymers by drug treatment or mutation broadens actin patch formation, apparently by enhancing Rop interactions with a positive regulator of actin polymerization. Thus, cross-talk between microtubule and actin microfilament networks is essential for coordinating and reinforcing pavement cell morphogenesis.
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Affiliation(s)
- A.M. Kotzer
- Department of Botany, University of British Columbia, 3529–6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - G.O. Wasteneys
- Department of Botany, University of British Columbia, 3529–6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
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