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Ford CM, Sweetman C, Fry SC. Ascorbate degradation: pathways, products, and possibilities. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2733-2739. [PMID: 38349794 PMCID: PMC11066805 DOI: 10.1093/jxb/erae048] [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: 12/13/2023] [Accepted: 02/06/2024] [Indexed: 02/15/2024]
Abstract
A role for l-ascorbate as the precursor of several plant compounds adds to its already broad metabolic utility. There are many examples of plant species in which oxalate and l-threonate are formed from l-ascorbate breakdown, and a number of roles have been proposed for this: structural, physiological, and biochemical. On the other hand, the synthesis of l-tartrate from l-ascorbate remains limited to a very few species, amongst which we must be grateful to count the domesticated grapevine Vitis vinifera and its relatives on which wine production is based. Pathways for the degradation of ascorbate were first proposed ~50 years ago and have formed the basis of more recent biochemical and molecular analyses. The present review seeks to summarize some of these findings and to propose opportunities for future research.
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Affiliation(s)
- Christopher M Ford
- School of Agriculture, Food and Wine and Waite Research Institute, The University of Adelaide, 5005, Australia
| | - Crystal Sweetman
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, South Australia
| | - Stephen C Fry
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, The King’s Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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2
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Stepnov AA, Christensen IA, Forsberg Z, Aachmann FL, Courtade G, Eijsink VGH. The impact of reductants on the catalytic efficiency of a lytic polysaccharide monooxygenase and the special role of dehydroascorbic acid. FEBS Lett 2021; 596:53-70. [PMID: 34845720 DOI: 10.1002/1873-3468.14246] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022]
Abstract
Monocopper lytic polysaccharide monooxygenases (LPMOs) catalyse oxidative cleavage of glycosidic bonds in a reductant-dependent reaction. Recent studies indicate that LPMOs, rather than being O2 -dependent monooxygenases, are H2 O2 -dependent peroxygenases. Here, we describe SscLPMO10B, a novel LPMO from the phytopathogenic bacterium Streptomyces scabies and address links between this enzyme's catalytic rate and in situ hydrogen peroxide production in the presence of ascorbic acid, gallic acid and l-cysteine. Studies of Avicel degradation showed a clear correlation between the catalytic rate of SscLPMO10B and the rate of H2 O2 generation in the reaction mixture. We also assessed the impact of oxidised ascorbic acid, dehydroascorbic acid (DHA), on LPMO activity, since DHA, which is not considered a reductant, was recently reported to drive LPMO reactions. Kinetic studies, combined with NMR analysis, showed that DHA is unstable and converts into multiple derivatives, some of which are redox active and can fuel the LPMO reaction by reducing the active site copper and promoting H2 O2 production. These results show that the apparent monooxygenase activity observed in SscLPMO10B reactions without exogenously added H2 O2 reflects a peroxygenase reaction.
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Affiliation(s)
- Anton A Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, Ås, Norway
| | - Idd A Christensen
- NOBIPOL, Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, Trondheim, Norway
| | - Zarah Forsberg
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, Ås, Norway
| | - Finn L Aachmann
- NOBIPOL, Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, Trondheim, Norway
| | - Gaston Courtade
- NOBIPOL, Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, Trondheim, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, Ås, Norway
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3
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Bozzo GG, Unterlander N. In through the out door: Biochemical mechanisms affecting flavonoid glycoside catabolism in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 308:110904. [PMID: 34034864 DOI: 10.1016/j.plantsci.2021.110904] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 03/27/2021] [Accepted: 03/31/2021] [Indexed: 06/12/2023]
Abstract
Plants are the sole source of flavonoids, a chemical category that includes flavonols. For the most part, flavonols occur as glycosides with numerous postulated biological roles in plants, including photoprotection, modulation of hormone translocation, and sequestration of reactive oxygen species. Flavonol glycosides are often considered as dead-end metabolites because related flavonoids (i.e., anthocyanins) occur in terminal tissues such as flowers and fruit, but recent evidence points to their turnover in planta, including developing photosynthetic tissues. Although microbial degradation pathways for flavonol glycosides of plant origin are well described, plant catabolic pathways are little studied by comparison. This review will address our current understanding of biochemical processes leading to the loss of flavonol glycosides in plants, with a specific emphasis on the evidence for flavonol-specific β-glucosidases. Complete elucidation of these catabolic pathways is dependent on the identification of regiospecific modifying steps, including enzymes associated with the hydrolysis of rhamnosylated flavonols, as well as flavonol peroxidation and their encoding genes. Herein, we highlight challenges for the identification of hypothetical plant α-rhamnosidases and peroxidases involved in flavonol glycoside degradation, and the potential biological role of this catabolism in mitigating oxidative stress in developing and postharvest plant tissues.
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Affiliation(s)
- Gale G Bozzo
- Department of Plant Agriculture, University of Guelph, 50 Stone Rd E., Guelph, ON, N1G 2W1, Canada.
| | - Nicole Unterlander
- Department of Plant Agriculture, University of Guelph, 50 Stone Rd E., Guelph, ON, N1G 2W1, Canada
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Burbidge CA, Ford CM, Melino VJ, Wong DCJ, Jia Y, Jenkins CLD, Soole KL, Castellarin SD, Darriet P, Rienth M, Bonghi C, Walker RP, Famiani F, Sweetman C. Biosynthesis and Cellular Functions of Tartaric Acid in Grapevines. FRONTIERS IN PLANT SCIENCE 2021; 12:643024. [PMID: 33747023 PMCID: PMC7970118 DOI: 10.3389/fpls.2021.643024] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 02/09/2021] [Indexed: 05/29/2023]
Abstract
Tartaric acid (TA) is an obscure end point to the catabolism of ascorbic acid (Asc). Here, it is proposed as a "specialized primary metabolite", originating from carbohydrate metabolism but with restricted distribution within the plant kingdom and lack of known function in primary metabolic pathways. Grapes fall into the list of high TA-accumulators, with biosynthesis occurring in both leaf and berry. Very little is known of the TA biosynthetic pathway enzymes in any plant species, although recently some progress has been made in this space. New technologies in grapevine research such as the development of global co-expression network analysis tools and genome-wide association studies, should enable more rapid progress. There is also a lack of information regarding roles for this organic acid in plant metabolism. Therefore this review aims to briefly summarize current knowledge about the key intermediates and enzymes of TA biosynthesis in grapes and the regulation of its precursor, ascorbate, followed by speculative discussion around the potential roles of TA based on current knowledge of Asc metabolism, TA biosynthetic enzymes and other aspects of fruit metabolism.
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Affiliation(s)
| | | | | | - Darren Chern Jan Wong
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Yong Jia
- Western Barley Genetic Alliance, Murdoch University, Perth, WA, Australia
| | | | - Kathleen Lydia Soole
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Simone Diego Castellarin
- Wine Research Centre, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC, Canada
| | - Philippe Darriet
- Université Bordeaux, Unité de recherche OEnologie, EA 4577, USC 1366 INRAE, Institut des Sciences de la Vigne et du Vin, Villenave d’Ornon, France
| | - Markus Rienth
- University of Sciences and Art Western Switzerland, Changins College for Viticulture and Oenology, Nyon, Switzerland
| | - Claudio Bonghi
- Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Legnaro, Italy
| | - Robert Peter Walker
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Perugia, Italy
| | - Franco Famiani
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Perugia, Italy
| | - Crystal Sweetman
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
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5
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Xiao M, Li Z, Zhu L, Wang J, Zhang B, Zheng F, Zhao B, Zhang H, Wang Y, Zhang Z. The Multiple Roles of Ascorbate in the Abiotic Stress Response of Plants: Antioxidant, Cofactor, and Regulator. FRONTIERS IN PLANT SCIENCE 2021; 12:598173. [PMID: 33912200 PMCID: PMC8072462 DOI: 10.3389/fpls.2021.598173] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/17/2021] [Indexed: 05/13/2023]
Abstract
Ascorbate (ASC) plays a critical role in plant stress response. The antioxidant role of ASC has been well-studied, but there are still several confusing questions about the function of ASC in plant abiotic stress response. ASC can scavenge reactive oxygen species (ROS) and should be helpful for plant stress tolerance. But in some cases, increasing ASC content impairs plant abiotic stress tolerance, whereas, inhibiting ASC synthesis or regeneration enhances plant stress tolerance. This confusing phenomenon indicates that ASC may have multiple roles in plant abiotic stress response not just as an antioxidant, though many studies more or less ignored other roles of ASC in plant. In fact, ACS also can act as the cofactor of some enzymes, which are involved in the synthesis, metabolism, and modification of a variety of substances, which has important effects on plant stress response. In addition, ASC can monitor and effectively regulate cell redox status. Therefore, we believe that ASC has atleast triple roles in plant abiotic stress response: as the antioxidant to scavenge accumulated ROS, as the cofactor to involve in plant metabolism, or as the regulator to coordinate the actions of various signal pathways under abiotic stress. The role of ASC in plant abiotic stress response is important and complex. The detail role of ASC in plant abiotic stress response should be analyzed according to specific physiological process in specific organ. In this review, we discuss the versatile roles of ASC in the response of plants to abiotic stresses.
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Affiliation(s)
- Minggang Xiao
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Zixuan Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Li Zhu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Jiayi Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Bo Zhang
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Fuyu Zheng
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Beiping Zhao
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Haiwen Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Yujie Wang
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
- Yujie Wang,
| | - Zhijin Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
- *Correspondence: Zhijin Zhang,
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6
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Dewhirst RA, Murray L, Mackay CL, Sadler IH, Fry SC. Characterisation of the non-oxidative degradation pathway of dehydroascorbic acid in slightly acidic aqueous solution. Arch Biochem Biophys 2019; 681:108240. [PMID: 31883928 DOI: 10.1016/j.abb.2019.108240] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/16/2019] [Accepted: 12/23/2019] [Indexed: 12/12/2022]
Abstract
Although l-ascorbate (vitamin C) is an important biological antioxidant, its degradation pathways in vivo remain incompletely characterised. Ascorbate is oxidised to dehydroascorbic acid, which can be either hydrolysed to diketogulonate (DKG) or further oxidised. DKG can be further degraded, oxidatively or non-oxidatively. Here we characterise DKG products formed non-enzymically and non-oxidatively at 20 °C and at a slightly acidic pH typical of the plant apoplast. High-voltage electrophoresis revealed at least five products, including two novel CPLs (epimers of 2-carboxy-l-threo-pentonolactone), which slowly interconverted with CPA (2-carboxy-l-threo-pentonate). One of the two CPLs has an exceptionally low pKa. The CPL structures were supported by MS [(C6H7O7)-] and by 1H and 13C NMR spectroscopy. Xylonate and its lactone also appeared. Experiments with [1-14C]DKG showed that all five products (including the 5-carbon xylonate and its lactone) retained DKG's carbon-1; therefore, most xylonate arose by decarboxylation of CPLs or CPA, one of whose -COOH groups originates from C-2 or C-3 of DKG after a 'benzilic acid rearrangement'. Since CPLs appeared before CPA, a DKG lactone is probably the main species undergoing this rearrangement. CPA and CPL also form non-enzymically in vivo, where they may be useful to researchers as 'fingerprints', or to organisms as 'signals', indicating a non-oxidative, slightly acidic biological compartment.
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Affiliation(s)
- Rebecca A Dewhirst
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, The King's Buildings, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Lorna Murray
- EastCHEM School of Chemistry, The University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FJ, UK
| | - C Logan Mackay
- EastCHEM School of Chemistry, The University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FJ, UK
| | - Ian H Sadler
- EastCHEM School of Chemistry, The University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FJ, UK
| | - Stephen C Fry
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, The King's Buildings, Max Born Crescent, Edinburgh, EH9 3BF, UK.
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7
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Hasanuzzaman M, Bhuyan MHMB, Anee TI, Parvin K, Nahar K, Mahmud JA, Fujita M. Regulation of Ascorbate-Glutathione Pathway in Mitigating Oxidative Damage in Plants under Abiotic Stress. Antioxidants (Basel) 2019; 8:E384. [PMID: 31505852 PMCID: PMC6770940 DOI: 10.3390/antiox8090384] [Citation(s) in RCA: 382] [Impact Index Per Article: 76.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/25/2019] [Accepted: 09/05/2019] [Indexed: 01/08/2023] Open
Abstract
Reactive oxygen species (ROS) generation is a usual phenomenon in a plant both under a normal and stressed condition. However, under unfavorable or adverse conditions, ROS production exceeds the capacity of the antioxidant defense system. Both non-enzymatic and enzymatic components of the antioxidant defense system either detoxify or scavenge ROS and mitigate their deleterious effects. The Ascorbate-Glutathione (AsA-GSH) pathway, also known as Asada-Halliwell pathway comprises of AsA, GSH, and four enzymes viz. ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase, play a vital role in detoxifying ROS. Apart from ROS detoxification, they also interact with other defense systems in plants and protect the plants from various abiotic stress-induced damages. Several plant studies revealed that the upregulation or overexpression of AsA-GSH pathway enzymes and the enhancement of the AsA and GSH levels conferred plants better tolerance to abiotic stresses by reducing the ROS. In this review, we summarize the recent progress of the research on AsA-GSH pathway in terms of oxidative stress tolerance in plants. We also focus on the defense mechanisms as well as molecular interactions.
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Affiliation(s)
- Mirza Hasanuzzaman
- Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
| | - M H M Borhannuddin Bhuyan
- Laboratory of Plant Stress Responses, Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan.
- Citrus Research Station, Bangladesh Agricultural Research Institute, Jaintapur, Sylhet 3156, Bangladesh.
| | - Taufika Islam Anee
- Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
| | - Khursheda Parvin
- Laboratory of Plant Stress Responses, Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan.
- Department of Horticulture, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
| | - Kamrun Nahar
- Department of Agricultural Botany, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
| | - Jubayer Al Mahmud
- Department of Agroforestry and Environmental Science, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
| | - Masayuki Fujita
- Laboratory of Plant Stress Responses, Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan.
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8
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Miyazawa T, Matsumoto A, Miyahara Y. Determination of cellular vitamin C dynamics by HPLC-DAD. Analyst 2019; 144:3483-3487. [PMID: 30892295 DOI: 10.1039/c8an02240b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A redox-sensitive inter-conversion between ascorbic acid (ASC) and its oxidized form dehydroascorbic acid (DHA) in the intracellular environment has been of exceptional interest to recent metabolomics and pharmaceutical research. We developed a chromatographic protocol to instantly determine these vitamers with each identity from cellular extracts, without any labeling and pretreatments. Owing to its simplicity, one can readily continue the assay for hours, an otherwise difficult to cover timescale at which the intracellular DHA-ASC conversion comes into play. The method was validated for the analysis of pancreatic cancer cells, to our knowledge the first-ever study on a nucleated cell type, to trace in detail their kinetics of glucose transporter-dependent DHA uptake and, simultaneously, that for the intracellular ASC conversion. The simplest of all the relevant techniques and yet with the unique ability to provide each vitamer identity on a high-throughput basis, this method should offer the most practical option for VC-involved physiological and pharmaceutical studies including high-dose VC cancer therapy.
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Affiliation(s)
- Taiki Miyazawa
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
| | - Akira Matsumoto
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan. and Kanagawa Institute of Industrial Science and Technology (KISTEC-KAST), Kawasaki 213-0012, Japan
| | - Yuji Miyahara
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
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Smirnoff N, Arnaud D. Hydrogen peroxide metabolism and functions in plants. THE NEW PHYTOLOGIST 2019; 221:1197-1214. [PMID: 30222198 DOI: 10.1111/nph.15488] [Citation(s) in RCA: 392] [Impact Index Per Article: 78.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/28/2018] [Indexed: 05/18/2023]
Abstract
Contents Summary 1197 I. Introduction 1198 II. Measurement and imaging of H2 O2 1198 III. H2 O2 and O2·- toxicity 1199 IV. Production of H2 O2 : enzymes and subcellular locations 1200 V. H2 O2 transport 1205 VI. Control of H2 O2 concentration: how and where? 1205 VII. Metabolic functions of H2 O2 1207 VIII. H2 O2 signalling 1207 IX. Where next? 1209 Acknowledgements 1209 References 1209 SUMMARY: Hydrogen peroxide (H2 O2 ) is produced, via superoxide and superoxide dismutase, by electron transport in chloroplasts and mitochondria, plasma membrane NADPH oxidases, peroxisomal oxidases, type III peroxidases and other apoplastic oxidases. Intracellular transport is facilitated by aquaporins and H2 O2 is removed by catalase, peroxiredoxin, glutathione peroxidase-like enzymes and ascorbate peroxidase, all of which have cell compartment-specific isoforms. Apoplastic H2 O2 influences cell expansion, development and defence by its involvement in type III peroxidase-mediated polymer cross-linking, lignification and, possibly, cell expansion via H2 O2 -derived hydroxyl radicals. Excess H2 O2 triggers chloroplast and peroxisome autophagy and programmed cell death. The role of H2 O2 in signalling, for example during acclimation to stress and pathogen defence, has received much attention, but the signal transduction mechanisms are poorly defined. H2 O2 oxidizes specific cysteine residues of target proteins to the sulfenic acid form and, similar to other organisms, this modification could initiate thiol-based redox relays and modify target enzymes, receptor kinases and transcription factors. Quantification of the sources and sinks of H2 O2 is being improved by the spatial and temporal resolution of genetically encoded H2 O2 sensors, such as HyPer and roGFP2-Orp1. These H2 O2 sensors, combined with the detection of specific proteins modified by H2 O2 , will allow a deeper understanding of its signalling roles.
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Affiliation(s)
- Nicholas Smirnoff
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Dominique Arnaud
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
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10
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Jana GA, Al Kharusi L, Sunkar R, Al-Yahyai R, Yaish MW. Metabolomic analysis of date palm seedlings exposed to salinity and silicon treatments. PLANT SIGNALING & BEHAVIOR 2019; 14:1663112. [PMID: 31505987 PMCID: PMC6804709 DOI: 10.1080/15592324.2019.1663112] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 05/21/2023]
Abstract
Silicon is known to promote plant growth as well as stress tolerance of plants. The current study was undertaken to assess the growth promoting effect of silicon on date palm seedling development as well as its ability to abate some of the negative effects of salinity. In this study, date palm seedlings were treated with silicon and sodium chloride salts, and the effect of these salts on some physiological parameters of the plants was determined. In addition, a global nontargeted metabolomics analysis was performed for the leaf and root tissues using liquid chromatography-mass spectrometry (LC-MS). The results showed that under non-stress conditions, silicon treatment enhanced the growth of the date palm seedlings, however, under salinity, silicon slightly mitigates the negative effects of salt stress on the date palm seedlings although it enhances the potassium accumulation under this condition. The global metabolomics analysis has identified a total of 1,101 significant differentially accumulated (p, q ≤ 0.05) metabolites in leaves and roots under silicon, salinity or their combination. A differential pairwise metabolic profile comparison revealed the accumulation of distinct metabolites in response to silicon and salinity treatments such as antioxidant compounds pyridoxine, cepharanthine, allithiamine, myristic acid and boldine; osmoregulators such as mucic acid; along with the accumulation of detoxification intermediates such as S-D-lactoylglutathione, beta-cyano-L-alanine and gamma-glutamyl-conjugates. In addition, histochemical analyses revealed that application of silicon significantly (p ≤ 0.05) enhanced the formation of the Casparian strip. Identification of the differentially accumulated metabolites could offer an insight into how silicon is able to promote growth and salinity tolerance in date palms.
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Affiliation(s)
- Gerry Aplang Jana
- Department of Biology, College of Sciences, Sultan Qaboos University, Muscat, Oman
| | - Latifa Al Kharusi
- Department of Biology, College of Sciences, Sultan Qaboos University, Muscat, Oman
| | - Ramanjulu Sunkar
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Rashid Al-Yahyai
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat, Oman
| | - Mahmoud W. Yaish
- Department of Biology, College of Sciences, Sultan Qaboos University, Muscat, Oman
- CONTACT Mahmoud W. Yaish , Department of Biology, College of Sciences, Sultan Qaboos University, P.O. Box 36, Muscat 123, Oman
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11
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Development and In Vitro Evaluation of Linear PEI-Shelled Heparin/Berberine Nanoparticles in Human Osteosarcoma U-2 OS Cells. Molecules 2018; 23:molecules23123122. [PMID: 30487471 PMCID: PMC6320921 DOI: 10.3390/molecules23123122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/19/2018] [Accepted: 11/27/2018] [Indexed: 01/05/2023] Open
Abstract
Berberine (BBR), a natural isoquinoline alkaloid derived from Chinese herbs, exerts many biological effects, including antiviral, antimicrobial, antidiarrhea, anti-inflammatory, and antitumor effects. In this study, a novel berberine nanoparticle (NP) consisting of heparin (HP) and BBR with or without being shelled with linear polyethyleneimine (LPEI) was developed to enhance its antitumor activity on osteosarcoma U-2 OS cells. With varying ratios of HP to BBR, HP/BBR NPs had a size ranging from 218.4 ± 3.9 to 282.0 ± 5.1 nm and zeta potential from -35.7 ± 0.4 to -51.9 ± 1.8 mV. After shelling with LPEI, the resultant NPs (HP/BBR/LPEI) possessed a size ranging from 226.3 ± 3.0 to 405.7 ± 85.2 nm and zeta potential from -46.5 ± 0.3 to -35.6 ± 0.5 mV; the encapsulation rate of BBR was close to 80%. The release profiles of both NPs were revealed to be slower than that of BBR solution. Results also showed that BBR and its two derived NPs reduced the viability of U-2 OS cells, and BBR NPs increased the cellular uptake of BBR. Cells were arrested at the G₁ phase when treated individually with BBR and the two NPs (HP/BBR and HP/BBR/LPEI) and DNA condensation was induced. In addition, BBR and BBR NPs reduced the expression of mouse double minute 2 homolog (MDM2) but increased that of p53, and BBR NPs enhanced apoptotic effects. In short, heparin-based nanoparticles could be potential carriers for osteosarcoma treatment.
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12
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Dewhirst RA, Fry SC. The oxidation of dehydroascorbic acid and 2,3-diketogulonate by distinct reactive oxygen species. Biochem J 2018; 475:3451-3470. [PMID: 30348642 PMCID: PMC6225978 DOI: 10.1042/bcj20180688] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/17/2018] [Accepted: 10/22/2018] [Indexed: 12/20/2022]
Abstract
l-Ascorbate, dehydro-l-ascorbic acid (DHA), and 2,3-diketo-l-gulonate (DKG) can all quench reactive oxygen species (ROS) in plants and animals. The vitamin C oxidation products thereby formed are investigated here. DHA and DKG were incubated aerobically at pH 4.7 with peroxide (H2O2), 'superoxide' (a ∼50 : 50 mixture of [Formula: see text] and [Formula: see text]), hydroxyl radicals (•OH, formed in Fenton mixtures), and illuminated riboflavin (generating singlet oxygen, 1O2). Products were monitored electrophoretically. DHA quenched H2O2 far more effectively than superoxide, but the main products in both cases were 4-O-oxalyl-l-threonate (4-OxT) and smaller amounts of 3-OxT and OxA + threonate. H2O2, but not superoxide, also yielded cyclic-OxT. Dilute Fenton mixture almost completely oxidised a 50-fold excess of DHA, indicating that it generated oxidant(s) greatly exceeding the theoretical •OH yield; it yielded oxalate, threonate, and OxT. 1O2 had no effect on DHA. DKG was oxidatively decarboxylated by H2O2, Fenton mixture, and 1O2, forming a newly characterised product, 2-oxo-l-threo-pentonate (OTP; '2-keto-l-xylonate'). Superoxide yielded negligible OTP. Prolonged H2O2 treatment oxidatively decarboxylated OTP to threonate. Oxidation of DKG by H2O2, Fenton mixture, or 1O2 also gave traces of 4-OxT but no detectable 3-OxT or cyclic-OxT. In conclusion, DHA and DKG yield different oxidation products when attacked by different ROS. DHA is more readily oxidised by H2O2 and superoxide; DKG more readily by 1O2 The diverse products are potential signals, enabling organisms to respond appropriately to diverse stresses. Also, the reaction-product 'fingerprints' are analytically useful, indicating which ROS are acting in vivo.
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Affiliation(s)
- Rebecca A Dewhirst
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, The King's Buildings, Edinburgh EH9 3BF, U.K
| | - Stephen C Fry
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, The King's Buildings, Edinburgh EH9 3BF, U.K.
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Yang J, Wu C, Yu Y, Mao H, Bao Y, Kang Y, Qi Z. A mongolian pine specific endoplasmic reticulum localized CALMODULIN-LIKE calcium binding protein enhances arabidopsis growth. JOURNAL OF PLANT PHYSIOLOGY 2018; 226:1-11. [PMID: 29689429 DOI: 10.1016/j.jplph.2018.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/07/2018] [Accepted: 04/10/2018] [Indexed: 06/08/2023]
Abstract
Stress-adapted wild plants are natural sources of novel genes for molecular breeding. Here, we conducted a transcriptional analysis of Pinus sylvestris var. mongolica Litv, an evergreen pine in northeastern China, to identify a novel CALMODULIN-LIKE protein-encoding gene, PsCML1, no significant homologs found in other plant species. PsCML1 encodes a protein predicted to have a single trans-membrane domain at its N-terminal. Four EF-hand motifs (calcium [Ca]-binding structures) are located at its C-terminal and showed Ca2+-specific affinity in isothermal titration calorimetric analysis. Transient expression of PsCML1 in Nicotiana benthamiana showed that the PsCML1 localizes to the endoplasmic reticulum (ER). Heterologous expression of PsCML1 in Arabidopsis significantly promoted seedling growth, and increased resistance to stress from NaCl and Ca2+ deficiency. The roots of the transgenic seedlings had higher contents of cellulose and pectin, but less hemicellulose than those of the wild type (WT). The biosynthesis of cell wall components is linked with protein glycosylation in the ER and reactive oxygen species (ROS) homeostasis. No significant difference was found in the extent of protein glycosylation between the transgenic and WT plants. However, the transgenic roots had higher steady-state levels of ROS, NADPH oxidase activity, and endo-membrane dynamics than those of the WT. A working model was proposed to delineate the interaction among Ca2+, ROS homeostasis, and cell wall loosening-dependent cell division.
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Affiliation(s)
- Jia Yang
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China; Inner Mongolia HeSheng Institute of Ecological Sciences & Technology, Hohhot, 011517, PR China
| | - Caili Wu
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China
| | - Yahui Yu
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China
| | - Huiping Mao
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China
| | - Yuying Bao
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China.
| | - Yan Kang
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China.
| | - Zhi Qi
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, PR China.
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Smirnoff N. Ascorbic acid metabolism and functions: A comparison of plants and mammals. Free Radic Biol Med 2018; 122:116-129. [PMID: 29567393 PMCID: PMC6191929 DOI: 10.1016/j.freeradbiomed.2018.03.033] [Citation(s) in RCA: 275] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/15/2018] [Accepted: 03/17/2018] [Indexed: 02/07/2023]
Abstract
Ascorbic acid is synthesised by eukaryotes, the known exceptions being primates and some other animal groups which have lost functional gulonolactone oxidase. Prokaryotes do not synthesise ascorbate and do not need an ascorbate supply, so the functions that are essential for mammals and plants are not required or are substituted by other compounds. The ability of ascorbate to donate electrons enables it to act as a free radical scavenger and to reduce higher oxidation states of iron to Fe2+. These reactions are the basis of its biological activity along with the relative stability of the resulting resonance stabilised monodehydroascorbate radical. The importance of these properties is emphasised by the evolution of at least three biosynthetic pathways and production of an ascorbate analogue, erythroascorbate, by fungi. The iron reducing activity of ascorbate maintains the reactive centre Fe2+ of 2-oxoglutarate-dependent dioxygenases (2-ODDs) thus preventing inactivation. These enzymes have diverse functions and, recently, the possibility that ascorbate status in mammals could influence 2-ODDs involved in histone and DNA demethylation thereby influencing stem cell differentiation and cancer has been uncovered. Ascorbate is involved in iron uptake and transport in plants and animals. While the above biochemical functions are shared between mammals and plants, ascorbate peroxidase (APX) is an enzyme family limited to plants and photosynthetic protists. It provides these organisms with increased capacity to remove H2O2 produced by photosynthetic electron transport and photorespiration. The Fe reducing activity of ascorbate enables hydroxyl radical production (pro-oxidant effect) and the reactivity of dehydroascorbate (DHA) and reaction of its degradation products with proteins (dehydroascorbylation and glycation) is potentially damaging. Ascorbate status influences gene expression in plants and mammals but at present there is little evidence that it acts as a specific signalling molecule. It most likely acts indirectly by influencing the redox state of thiols and 2-ODD activity. However, the possibility that dehydroascorbylation is a regulatory post-translational protein modification could be explored.
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Affiliation(s)
- Nicholas Smirnoff
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK.
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15
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Dewhirst RA, Fry SC. Oxalyltransferase, a plant cell-wall acyltransferase activity, transfers oxalate groups from ascorbate metabolites to carbohydrates. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:743-757. [PMID: 29882267 PMCID: PMC6099474 DOI: 10.1111/tpj.13984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 05/07/2023]
Abstract
In the plant apoplast, ascorbate is oxidised, via dehydroascorbic acid, to O-oxalyl esters [oxalyl-l-threonate (OxT) and cyclic oxalyl-l-threonate (cOxT)]. We tested whether OxT and cOxT can donate the oxalyl group in transacylation reactions to form oxalyl-polysaccharides, potentially modifying the cell wall. [oxalyl-14 C]OxT was incubated with living spinach (Spinacia oleracea) and Arabidopsis cell-suspension cultures in the presence or absence of proposed acceptor substrates (carbohydrates). In addition, [14 C]OxT and [14 C]cOxT were incubated in vitro with cell-wall enzyme preparations plus proposed acceptor substrates. Radioactive products were monitored electrophoretically. Oxalyltransferase activity was detected. Living cells incorporated oxalate groups from OxT into cell-wall polymers via ester bonds. When sugars were added, [14 C]oxalyl-sugars were formed, in competition with OxT hydrolysis. Preferred acceptor substrates were carbohydrates possessing primary alcohols e.g. glucose. A model transacylation product, [14 C]oxalyl-glucose, was relatively stable in vivo (half-life >24 h), whereas [14 C]OxT underwent rapid turnover (half-life ~6 h). Ionically wall-bound enzymes catalysed similar transacylation reactions in vitro with OxT or cOxT as oxalyl donor substrates and any of a range of sugars or hemicelluloses as acceptor substrates. Glucosamine was O-oxalylated, not N-oxalylated. We conclude that plants possess apoplastic acyltransferase (oxalyltransferase) activity that transfers oxalyl groups from ascorbate catabolites to carbohydrates, forming relatively long-lived O-oxalyl-carbohydrates. The findings increase the range of known metabolites whose accumulation in vivo indicates vitamin C catabolism. Possible signalling roles of the resulting oxalyl-sugars can now be investigated, as can the potential ability of polysaccharide oxalylation to modify the wall's physical properties.
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Affiliation(s)
- Rebecca A. Dewhirst
- The Edinburgh Cell Wall GroupInstitute of Molecular Plant SciencesThe University of EdinburghEdinburghEH9 3BFUK
- Present address:
wildFIRE labHatherly LaboratoriesPrince of Wales RoadUniversity of ExeterExeterUK
| | - Stephen C. Fry
- The Edinburgh Cell Wall GroupInstitute of Molecular Plant SciencesThe University of EdinburghEdinburghEH9 3BFUK
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16
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Veličković D, Chu RK, Carrell AA, Thomas M, Paša-Tolić L, Weston DJ, Anderton CR. Multimodal MSI in Conjunction with Broad Coverage Spatially Resolved MS 2 Increases Confidence in Both Molecular Identification and Localization. Anal Chem 2017; 90:702-707. [PMID: 29210566 DOI: 10.1021/acs.analchem.7b04319] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
One critical aspect of mass spectrometry imaging (MSI) is the need to confidently identify detected analytes. While orthogonal tandem MS (e.g., LC-MS2) experiments from sample extracts can assist in annotating ions, the spatial information about these molecules is lost. Accordingly, this could cause mislead conclusions, especially in cases where isobaric species exhibit different distributions within a sample. In this Technical Note, we employed a multimodal imaging approach, using matrix assisted laser desorption/ionization (MALDI)-MSI and liquid extraction surface analysis (LESA)-MS2I, to confidently annotate and localize a broad range of metabolites involved in a tripartite symbiosis system of moss, cyanobacteria, and fungus. We found that the combination of these two imaging modalities generated very congruent ion images, providing the link between highly accurate structural information onfered by LESA and high spatial resolution attainable by MALDI. These results demonstrate how this combined methodology could be very useful in differentiating metabolite routes in complex systems.
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Affiliation(s)
| | | | - Alyssa A Carrell
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States
| | | | | | - David J Weston
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States
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17
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Dewhirst RA, Clarkson GJJ, Rothwell SD, Fry SC. Novel insights into ascorbate retention and degradation during the washing and post-harvest storage of spinach and other salad leaves. Food Chem 2017; 233:237-246. [PMID: 28530571 PMCID: PMC5441274 DOI: 10.1016/j.foodchem.2017.04.082] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/03/2017] [Accepted: 04/14/2017] [Indexed: 11/19/2022]
Abstract
Post-harvest treatments of pre-packaged salad leaves potentially cause l-ascorbate loss, but the mechanisms of ascorbate degradation remain incompletely understood, especially in planta. We explored the extent and pathways of ascorbate loss in variously washed and stored salad leaves. Ascorbate was assayed by 2,6-dichlorophenolindophenol titration, and pathways were monitored by 14C-radiolabelling followed by high-voltage electrophoresis. All leaves tested showed ascorbate loss during storage: lettuce showed the greatest percentage loss, wild rocket the least. Spinach leaves were particularly prone to losing ascorbate during washing, especially with simultaneous mechanical agitation; however, washing in the presence of hypochlorite did not significantly increase ascorbate loss. In spinach, [14C]oxalate was the major product of [14C]ascorbate degradation, suggesting that commercial washing causes oxidative stress. This study highlights that ascorbate/dehydroascorbic acid are lost via the oxidative pathway during washing and post-harvest storage of salad leaves. Thus changes to washing procedures could potentially increase the post-harvest retention of ascorbate.
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Affiliation(s)
- Rebecca A Dewhirst
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, Daniel Rutherford Building, The King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK; wildFIRE Lab, Hatherly Laboratories, University of Exeter, Prince of Wales Road, Exeter EX4 4PS, UK(1)
| | - Graham J J Clarkson
- Vitacress, Lower Link Farm, St Mary Bourne, Andover, Hampshire SP11 6DB, UK; Edward Vinson Ltd, 4 Ewell Barn, Graveney Rd, Faversham ME13 8UP, UK(1)
| | - Steve D Rothwell
- Vitacress, Lower Link Farm, St Mary Bourne, Andover, Hampshire SP11 6DB, UK
| | - Stephen C Fry
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, Daniel Rutherford Building, The King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK.
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18
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Li R, Xin S, Tao C, Jin X, Li H. Cotton Ascorbate Oxidase Promotes Cell Growth in Cultured Tobacco Bright Yellow-2 Cells through Generation of Apoplast Oxidation. Int J Mol Sci 2017; 18:E1346. [PMID: 28644407 PMCID: PMC5535839 DOI: 10.3390/ijms18071346] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/09/2017] [Accepted: 06/19/2017] [Indexed: 01/31/2023] Open
Abstract
Ascorbate oxidase (AO) plays an important role in cell growth through the modulation of reduction/oxidation (redox) control of the apoplast. Here, a cotton (Gossypium hirsutum) apoplastic ascorbate oxidase gene (GhAO1) was obtained from fast elongating fiber tissues. GhAO1 belongs to the multicopper oxidase (MCO) family and includes a signal peptide and several transmembrane regions. Analyses of quantitative real-time polymerase chain reaction (QRT-PCR) and enzyme activity showed that GhAO1 was expressed abundantly in 15-day post-anthesis (dpa) wild-type (WT) fibers in comparison with fuzzless-lintless (fl) mutant ovules. Subcellular distribution analysis in onion cells demonstrated that GhAO1 is localized in the cell wall. In transgenic tobacco bright yellow-2 (BY-2) cells with ectopic overexpression of GhAO1, the enhancement of cell growth with 1.52-fold increase in length versus controls was indicated, as well as the enrichment of both total ascorbate in whole-cells and dehydroascorbate acid (DHA) in apoplasts. In addition, promoted activities of AO and monodehydroascorbate reductase (MDAR) in apoplasts and dehydroascorbate reductase (DHAR) in whole-cells were displayed in transgenic tobacco BY-2 cells. Accumulation of H₂O₂, and influenced expressions of Ca2+ channel genes with the activation of NtMPK9 and NtCPK5 and the suppression of NtTPC1B were also demonstrated in transgenic tobacco BY-2 cells. Finally, significant induced expression of the tobacco NtAO gene in WT BY-2 cells under indole-3-acetic acid (IAA) treatment appeared; however, the sensitivity of the NtAO gene expression to IAA disappeared in transgenic BY-2 cells, revealing that the regulated expression of the AO gene is under the control of IAA. Taken together, these results provide evidence that GhAO1 plays an important role in fiber cell elongation and may promote cell growth by generating the oxidation of apoplasts, via the auxin-mediated signaling pathway.
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Affiliation(s)
- Rong Li
- College of Life Sciences, Key laboratory of Agrobiotechnology, Shihezi University, Shihezi 832003, China.
| | - Shan Xin
- College of Life Sciences, Key laboratory of Agrobiotechnology, Shihezi University, Shihezi 832003, China.
| | - Chengcheng Tao
- College of Life Sciences, Key laboratory of Agrobiotechnology, Shihezi University, Shihezi 832003, China.
| | - Xiang Jin
- Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China.
| | - Hongbin Li
- College of Life Sciences, Key laboratory of Agrobiotechnology, Shihezi University, Shihezi 832003, China.
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