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Fan H, Huang G, Guo Q, Ma J, Huang Y, Huang S, Wei M, Xie C, Yan B, Zhao S, Chen G, Zheng J, Zhou Z, Gao H. Bioactive Phenylpropanoid Glycosides, Dimers, and Heterodimers from the Bark of Cinnamomum cassia (L.) J.Presl. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:16263-16275. [PMID: 38953591 DOI: 10.1021/acs.jafc.4c02129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Six new phenylpropanoid glycosides (1-6), two new phenylethanol glycosides (7 and 8), one new phenylmethanol glycoside (9), three new phenylpropanoid dimers (10-12), two new phenylpropanoid-flavan-3-ol heterodimers (13 and 14), and six known relevant compounds (15-20) were isolated and identified from the well-liked edible and medicinal substance (the bark of Cinnamomum cassia (L.) J.Presl). The structures of these isolates were determined by using spectroscopic analyses, chemical methods, and quantum chemical calculations. Notably, compounds 4-9 were rare apiuronyl-containing glycosides, and compounds 13 and 14 were heterodimers of phenylpropanoids and flavan-3-ols linked through C-9″-C-8 bonds. The antioxidant and α-glucosidase inhibitory activities of all isolates were evaluated. Compounds 10 and 12 exhibited DPPH radical scavenging capacities with IC50 values of 20.1 and 13.0 μM, respectively (vitamin C IC50 value of 14.3 μM). In the ORAC experiment, all these compounds exhibited different levels of capacity for scavenging free radicals, and compound 10 displayed extraordinary free radical scavenging capacity with the ORAC value of 6.42 ± 0.01 μM TE/μM (EGCG ORAC value of 1.54 ± 0.02 μM TE/μM). Compound 12 also showed significant α-glucosidase inhibitory activity with an IC50 of 56.3 μM (acarbose IC50 of 519.4 μM).
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Affiliation(s)
- Hongxia Fan
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Gengfeng Huang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Qi Guo
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China, Jinan University, Guangzhou 510632, People's Republic of China
| | - Jiahui Ma
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Yujing Huang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Shangxiong Huang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Meiwen Wei
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China, Jinan University, Guangzhou 510632, People's Republic of China
| | - Caihong Xie
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Bingbing Yan
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Suqing Zhao
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Guodong Chen
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China, Jinan University, Guangzhou 510632, People's Republic of China
| | - Junxia Zheng
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China
| | - Zhengqun Zhou
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China, Jinan University, Guangzhou 510632, People's Republic of China
| | - Hao Gao
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China, Jinan University, Guangzhou 510632, People's Republic of China
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Quiñones CO, Gesto-Borroto R, Wilson RV, Hernández-Madrigal SV, Lorence A. Alternative pathways leading to ascorbate biosynthesis in plants: lessons from the last 25 years. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2644-2663. [PMID: 38488689 DOI: 10.1093/jxb/erae120] [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: 12/05/2023] [Accepted: 03/14/2024] [Indexed: 05/04/2024]
Abstract
l-Ascorbic acid (AsA) is an antioxidant with important roles in plant stress physiology, growth, and development. AsA also plays an essential role in human health, preventing scurvy. Humans do not synthesize AsA, which needs to be supplied via a diet rich in fresh produce. Research efforts have provided progress in the elucidation of a complex metabolic network with at least four routes leading to AsA formation in plants. In this review, three alternative pathways, namely the d-galacturonate, the l-gulose, and the myo-inositol pathways, are presented with the supporting evidence of their operation in multiple plant species. We critically discuss feeding studies using precursors and their conversion to AsA in plant organs, and research where the expression of key genes encoding enzymes involved in the alternative pathways showed >100% AsA content increase in the transgenics and in many cases accompanied by enhanced tolerance to multiple stresses. We propose that the alternative pathways are vital in AsA production in response to stressful conditions and to compensate in cases where the flux through the d-mannose/l-galactose pathway is reduced. The genes and enzymes that have been characterized so far in these alternative pathways represent important tools that are being used to develop more climate-tolerant crops.
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Affiliation(s)
- Cherryl O Quiñones
- Arkansas Biosciences Institute, Arkansas State University, PO Box 639, State University, AR 72467, USA
| | - Reinier Gesto-Borroto
- Arkansas Biosciences Institute, Arkansas State University, PO Box 639, State University, AR 72467, USA
| | - Rachael V Wilson
- Arkansas Biosciences Institute, Arkansas State University, PO Box 639, State University, AR 72467, USA
| | - Sara V Hernández-Madrigal
- Arkansas Biosciences Institute, Arkansas State University, PO Box 639, State University, AR 72467, USA
| | - Argelia Lorence
- Arkansas Biosciences Institute, Arkansas State University, PO Box 639, State University, AR 72467, USA
- Department of Chemistry and Physics, Arkansas State University, PO Box 419, State University, AR 72467, USA
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Thakur N, Chaturvedi S, Tiwari S. Wheat derived glucuronokinase as a potential target for regulating ascorbic acid and phytic acid content with increased root length under drought and ABA stresses in Arabidopsis thaliana. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 331:111671. [PMID: 36931562 DOI: 10.1016/j.plantsci.2023.111671] [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: 12/01/2022] [Revised: 02/20/2023] [Accepted: 03/10/2023] [Indexed: 06/18/2023]
Abstract
Glucuronokinase (GlcAK) converts glucuronic acid into glucuronic acid-1-phosphate, which is then converted into UDP-glucuronic acid (UDP-GlcA) via myo-inositol oxygenase (MIOX) pathway. UDP-GlcA acts as a precursor in the synthesis of nucleotide-sugar moieties forming cell wall biomass. GlcAK being present at the bifurcation point between UDP-GlcA and ascorbic acid (AsA) biosyntheses, makes it necessary to study its role in plants. In this study, the three homoeologs of GlcAK gene from hexaploid wheat were overexpressed in Arabidopsis thaliana. The GlcAK overexpressing transgenic lines showed decreased contents of AsA and phytic acid (PA) as compared to control plants. Root length and seed germination analyses under abiotic stress (drought and abscisic acid) conditions revealed enhanced root length in transgenic lines as compared to control plants. These results indicate that the MIOX pathway might be contributing towards AsA biosynthesis as evident by the decreased AsA content in the GlcAK overexpressing transgenic Arabidopsis thaliana plants. Findings of the present study will enhance the understanding of the involvement of GlcAK gene in MIOX pathway and subsequent physiological effects in plants.
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Affiliation(s)
- Neha Thakur
- Plant Tissue Culture and Genetic Engineering Lab, National Agri-Food Biotechnology Institute (NABI), Department of Biotechnology, Ministry of Science and Technology (Government of India), Sector-81, Mohali 140306, Punjab, India; Department of Biotechnology, Panjab University, Chandigarh 160014, India
| | - Siddhant Chaturvedi
- Plant Tissue Culture and Genetic Engineering Lab, National Agri-Food Biotechnology Institute (NABI), Department of Biotechnology, Ministry of Science and Technology (Government of India), Sector-81, Mohali 140306, Punjab, India; Department of Biotechnology, Panjab University, Chandigarh 160014, India
| | - Siddharth Tiwari
- Plant Tissue Culture and Genetic Engineering Lab, National Agri-Food Biotechnology Institute (NABI), Department of Biotechnology, Ministry of Science and Technology (Government of India), Sector-81, Mohali 140306, Punjab, India.
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Contreras A, Jones MK, Eldon ED, Klig LS. Inositol in Disease and Development: Roles of Catabolism via myo-Inositol Oxygenase in Drosophila melanogaster. Int J Mol Sci 2023; 24:4185. [PMID: 36835596 PMCID: PMC9967586 DOI: 10.3390/ijms24044185] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 02/14/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
Inositol depletion has been associated with diabetes and related complications. Increased inositol catabolism, via myo-inositol oxygenase (MIOX), has been implicated in decreased renal function. This study demonstrates that the fruit fly Drosophila melanogaster catabolizes myo-inositol via MIOX. The levels of mRNA encoding MIOX and MIOX specific activity are increased when fruit flies are grown on a diet with inositol as the sole sugar. Inositol as the sole dietary sugar can support D. melanogaster survival, indicating that there is sufficient catabolism for basic energy requirements, allowing for adaptation to various environments. The elimination of MIOX activity, via a piggyBac WH-element inserted into the MIOX gene, results in developmental defects including pupal lethality and pharate flies without proboscises. In contrast, RNAi strains with reduced levels of mRNA encoding MIOX and reduced MIOX specific activity develop to become phenotypically wild-type-appearing adult flies. myo-Inositol levels in larval tissues are highest in the strain with this most extreme loss of myo-inositol catabolism. Larval tissues from the RNAi strains have inositol levels higher than wild-type larval tissues but lower levels than the piggyBac WH-element insertion strain. myo-Inositol supplementation of the diet further increases the myo-inositol levels in the larval tissues of all the strains, without any noticeable effects on development. Obesity and blood (hemolymph) glucose, two hallmarks of diabetes, were reduced in the RNAi strains and further reduced in the piggyBac WH-element insertion strain. Collectively, these data suggest that moderately increased myo-inositol levels do not cause developmental defects and directly correspond to reduced larval obesity and blood (hemolymph) glucose.
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Affiliation(s)
- Altagracia Contreras
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA 90840, USA
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Melissa K. Jones
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA 90840, USA
- Genentech, South San Francisco, CA 94080, USA
| | - Elizabeth D. Eldon
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA 90840, USA
| | - Lisa S. Klig
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA 90840, USA
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Su XB, Ko ALA, Saiardi A. Regulations of myo-inositol homeostasis: Mechanisms, implications, and perspectives. Adv Biol Regul 2023; 87:100921. [PMID: 36272917 DOI: 10.1016/j.jbior.2022.100921] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022]
Abstract
Phosphorylation is the most common module of cellular signalling pathways. The dynamic nature of phosphorylation, which is conferred by the balancing acts of kinases and phosphatases, allows this modification to finely control crucial cellular events such as growth, differentiation, and cell cycle progression. Although most research to date has focussed on protein phosphorylation, non-protein phosphorylation substrates also play vital roles in signal transduction. The most well-established substrate of non-protein phosphorylation is inositol, whose phosphorylation generates many important signalling molecules such as the second messenger IP3, a key factor in calcium signalling. A fundamental question to our understanding of inositol phosphorylation is how the levels of cellular inositol are controlled. While the availability of protein phosphorylation substrates is known to be readily controlled at the levels of transcription, translation, and/or protein degradation, the regulatory mechanisms that control the uptake, synthesis, and removal of inositol are underexplored. Potentially, such mechanisms serve as an important layer of regulation of cellular signal transduction pathways. There are two ways in which mammalian cells acquire inositol. The historic use of radioactive 3H-myo-inositol revealed that inositol is promptly imported from the extracellular environment by three specific symporters SMIT1/2, and HMIT, coupling sodium or proton entry, respectively. Inositol can also be synthesized de novo from glucose-6P, thanks to the enzymatic activity of ISYNA1. Intriguingly, emerging evidence suggests that in mammalian cells, de novo myo-inositol synthesis occurs irrespective of inositol availability in the environment, prompting the question of whether the two sources of inositol go through independent metabolic pathways, thus serving distinct functions. Furthermore, the metabolic stability of myo-inositol, coupled with the uptake and endogenous synthesis, determines that there must be exit pathways to remove this extraordinary sugar from the cells to maintain its homeostasis. This essay aims to review our current knowledge of myo-inositol homeostatic metabolism, since they are critical to the signalling events played by its phosphorylated forms.
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Affiliation(s)
- Xue Bessie Su
- Medical Research Council, Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - An-Li Andrea Ko
- Medical Research Council, Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - Adolfo Saiardi
- Medical Research Council, Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK.
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Kalogeropoulou E, Aliferis KA, Tjamos SE, Vloutoglou I, Paplomatas EJ. Combined Transcriptomic and Metabolomic Analysis Reveals Insights into Resistance of Arabidopsis bam3 Mutant against the Phytopathogenic Fungus Fusarium oxysporum. PLANTS (BASEL, SWITZERLAND) 2022; 11:3457. [PMID: 36559570 PMCID: PMC9785915 DOI: 10.3390/plants11243457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/28/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
The wilt-inducing strains of Fusarium oxysporum are responsible for severe damage to many economically important plant species. The most cost-effective and environmentally safe method for the management of Fusarium wilt is the use of resistant cultivars when they are available. In the present study, the Arabidopsis genotype with disruptions in the β-amylase 3 (BAM3) gene, which encodes the major hydrolytic enzyme that degrades starch to maltose, had significantly lower susceptibility to Fusarium oxysporum f. sp. raphani (For) compared to wild-type (wt) plants. It showed the lowest disease severity and contained reduced quantities of fungal DNA in the plant vascular tissues when analyzed with real-time PCR. Through metabolomic analysis using gas chromatography (GC)-mass spectrometry (MS) and gene-expression analysis by reverse-transcription quantitative PCR (RT-qPCR), we observed that defense responses of Arabidopsis bam3 mutants are associated with starch-degradation enzymes, the corresponding modification of the carbohydrate balance, and alterations in sugar (glucose, sucrose, trehalose, and myo-inositol) and auxin metabolism.
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Affiliation(s)
- Eleni Kalogeropoulou
- Laboratory of Mycology, Scientific Department of Phytopathology, Benaki Phytopathological Institute, 8 St. Delta Street, 145 61 Athens, Greece
| | - Konstantinos A. Aliferis
- Laboratory of Pesticide Science, Agricultural University of Athens, 75 Iera Odos Street, 118 55 Athens, Greece
| | - Sotirios E. Tjamos
- Laboratory of Plant Pathology, Agricultural University of Athens, 75 Iera Odos Street, 118 55 Athens, Greece
| | - Irene Vloutoglou
- Laboratory of Mycology, Scientific Department of Phytopathology, Benaki Phytopathological Institute, 8 St. Delta Street, 145 61 Athens, Greece
| | - Epaminondas J. Paplomatas
- Laboratory of Plant Pathology, Agricultural University of Athens, 75 Iera Odos Street, 118 55 Athens, Greece
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Potential of engineering the myo-inositol oxidation pathway to increase stress resilience in plants. Mol Biol Rep 2022; 49:8025-8035. [PMID: 35294703 DOI: 10.1007/s11033-022-07333-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
Abstract
Myo-inositol is one of the most abundant form of inositol. The myo-inositol (MI) serves as substrate to diverse biosynthesis pathways and hence it is conserved across life forms. The biosynthesis of MI is well studied in animals. Beyond biosynthesis pathway, implications of MI pathway and enzymes hold potential implications in plant physiology and crop improvement. Myo-inositol oxygenase (MIOX) enzyme catabolize MI into D-glucuronic acid (D-GlcUA). The MIOX enzyme family is well studied across few plants. More recently, the MI associated pathway's crosstalk with other important biosynthesis and stress responsive pathways in plants has drawn attention. The overall outcome from different plant species studied so far are very suggestive that MI derivatives and associated pathways could open new directions to explore stress responsive novel metabolic networks. There are evidences for upregulation of MI metabolic pathway genes, specially MIOX under different stress condition. We also found MIOX genes getting differentially expressed according to developmental and stress signals in Arabidopsis and wheat. In this review we try to highlight the missing links and put forward a tailored view over myo-inositol oxidation pathway and MIOX proteins.
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Comparison of the root, leaf and internode transcriptomes in Sugarcane (Saccharum spp. hybrids). CURRENT RESEARCH IN BIOTECHNOLOGY 2022. [DOI: 10.1016/j.crbiot.2022.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Mariette A, Kang HS, Heazlewood JL, Persson S, Ebert B, Lampugnani ER. Not Just a Simple Sugar: Arabinose Metabolism and Function in Plants. PLANT & CELL PHYSIOLOGY 2021; 62:1791-1812. [PMID: 34129041 DOI: 10.1093/pcp/pcab087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/05/2021] [Accepted: 06/15/2021] [Indexed: 06/12/2023]
Abstract
Growth, development, structure as well as dynamic adaptations and remodeling processes in plants are largely controlled by properties of their cell walls. These intricate wall structures are mostly made up of different sugars connected through specific glycosidic linkages but also contain many glycosylated proteins. A key plant sugar that is present throughout the plantae, even before the divergence of the land plant lineage, but is not found in animals, is l-arabinose (l-Ara). Here, we summarize and discuss the processes and proteins involved in l-Ara de novo synthesis, l-Ara interconversion, and the assembly and recycling of l-Ara-containing cell wall polymers and proteins. We also discuss the biological function of l-Ara in a context-focused manner, mainly addressing cell wall-related functions that are conferred by the basic physical properties of arabinose-containing polymers/compounds. In this article we explore these processes with the goal of directing future research efforts to the many exciting yet unanswered questions in this research area.
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Affiliation(s)
- Alban Mariette
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
- Max Planck Institute of Molecular Plant Physiology, Golm, Germany, Am Mühlenberg 1, Potsdam-Golm 14476, Germany
| | - Hee Sung Kang
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
| | - Joshua L Heazlewood
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
| | - Staffan Persson
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
- Department of Plant and Environmental Sciences, Copenhagen Plant Science Center (CPSC), University of Copenhagen, Thorvaldsensvej 40, Frederiksberg 1871, Denmark
- Joint International Research Laboratory of Metabolic and Developmental Sciences, State Key Laboratory of Hybrid Rice, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Berit Ebert
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
| | - Edwin R Lampugnani
- School of BioSciences, University of Melbourne, Parkville, VIC 3170, Australia
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Genome-wide identification of the MIOX gene family and their expression profile in cotton development and response to abiotic stress. PLoS One 2021; 16:e0254111. [PMID: 34242283 PMCID: PMC8270170 DOI: 10.1371/journal.pone.0254111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 06/18/2021] [Indexed: 11/19/2022] Open
Abstract
The enzyme myo-inositol oxygenase (MIOX) catalyzes the myo-inositol into glucuronic acid. In this study, 6 MIOX genes were identified from all of the three diploid cotton species (Gossypium arboretum, Gossypium herbaceum and Gossypium raimondii) and Gossypioides kirkii, 12 MIOX genes were identified from two domesticated tetraploid cottons Gossypium hirsutum, Gossypium barbadense, and 11 MIOX genes were identified from three wild tetraploid cottons Gossypium tomentosum, Gossypium mustelinum and Gossypium darwinii. The number of MIOX genes in tetraploid cotton genome is roughly twice that of diploid cotton genome. Members of MIOX family were classified into six groups based on the phylogenetic analysis. Integrated analysis of collinearity events and chromosome locations suggested that both whole genome duplication and segmental duplication events contributed to the expansion of MIOX genes during cotton evolution. The ratios of non-synonymous (Ka) and synonymous (Ks) substitution rates revealed that purifying selection was the main force driving the evolution of MIOX genes. Numerous cis-acting elements related to light responsive element, defense and stress responsive element were identified in the promoter of the MIOX genes. Expression analyses of MIOX genes based on RNA-seq data and quantitative real time PCR showed that MIOX genes within the same group shared similar expression patterns with each other. All of these results provide the foundation for further study of the biological functions of MIOX genes in cotton environmental adaptability.
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A Transcriptional Analysis of the Genes Involved in the Ascorbic Acid Pathways Based on a Comparison of the Juice and Leaves of Navel and Anthocyanin-Rich Sweet Orange Varieties. PLANTS 2021; 10:plants10071291. [PMID: 34202884 PMCID: PMC8309047 DOI: 10.3390/plants10071291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/18/2021] [Accepted: 06/20/2021] [Indexed: 11/23/2022]
Abstract
Sweet oranges are an important source of ascorbic acid (AsA). In this study, the content of AsA in the juice and leaves of four orange clonal selections, different in terms of maturity time and the presence/absence of anthocyanins, was correlated with the transcription levels of the main genes involved in the biosynthesis, recycling, and degradation pathways. Within each variety, differences in the above pathways and the AsA amount were found between the analysed tissues. Variations were also observed at different stages of fruit development and maturation. At the beginning of fruit development, AsA accumulation was attributable to the synergic action of l-galactose and Myo-inositol, while the l-gulose pathway was predominant between the end of fruit development and the beginning of ripening. In leaves, the l-galactose pathway appeared to play a major role in AsA accumulation, even though higher GalUr isoform expression suggests a synergistic contribution of both pathways in this tissue. In juice, the trend of the AsA content may be related to the decrease in the transcription levels of the GME, GDH, MyoOx, and GalUr12 genes. Newhall was the genotype that accumulated the most AsA. The difference between Newhall and the other varieties seems to be attributable to the GLDH, GalUr12, APX2, and DHAR3 genes.
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Jia T, Ge Q, Zhang S, Zhang Z, Liu A, Fan S, Jiang X, Feng Y, Zhang L, Niu D, Huang S, Gong W, Yuan Y, Shang H. UDP-Glucose Dehydrogenases: Identification, Expression, and Function Analyses in Upland Cotton ( Gossypium hirsutum). Front Genet 2021; 11:597890. [PMID: 33505427 PMCID: PMC7831515 DOI: 10.3389/fgene.2020.597890] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 11/27/2020] [Indexed: 11/17/2022] Open
Abstract
UDP-glucose dehydrogenase (UGD; EC1.1.1.22) is a NAD+-dependent enzyme that catalyzes the two-fold oxidation of UDP-glucose (UDP-Glc) to produce UDP-glucuronic acid and plays an important role in plant cell wall synthesis. A total of 42 UGD genes from four Gossypium genomes including G. hirsutum, G. arboretum, G. barbadense, and G. raimondii were identified and found that the UGD gene family has conservative evolution patterns in gene structure and protein domain. The growth of fibers can be effectively promoted after adding the UDP-Glc to the medium, and the GhUGD gene expression enhanced. In addition, the transgenic Arabidopsis lines over-expressing GH_D12G1806 had longer root lengths and higher gene expression level than the wild-type plants of Columbia-0. These results indicated that UGD may play important roles in cotton fiber development and has a guiding significance for dissecting fiber development mechanism.
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Affiliation(s)
- Tingting Jia
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Qun Ge
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Shuya Zhang
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Zhen Zhang
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Aiying Liu
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Senmiao Fan
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xiao Jiang
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Yulong Feng
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China
| | - Lipeng Zhang
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Doudou Niu
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Shen Huang
- Zhengzhou University of Light Industry College of Food and Bioengineering, Zhengzhou, China
| | - Wankui Gong
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Youlu Yuan
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China
| | - Haihong Shang
- State Key Laboratory of Cotton Biology, Key Laboratory of Biological and Genetic Breeding of Cotton, The Ministry of Agriculture, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China
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13
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Qian J, Zhang X, Yan Y, Wang N, Ge W, Zhou Q, Yang Y. Unravelling the molecular mechanisms of abscisic acid-mediated drought-stress alleviation in pomegranate (Punica granatum L.). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 157:211-218. [PMID: 33120112 DOI: 10.1016/j.plaphy.2020.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
Pomegranate (Punica granatum L.), a fruit tree of great economic and nutritional importance, is sensitive to drought stress, which largely affects its transplantation survival rate, fruit yield and quality. Abscisic acid (ABA) treatment can reduce the drought-induced adverse impacts on plants. However, our knowledge on the molecular mechanisms behind ABA-mediated drought tolerance in pomegranates is still limited. In this study, we treated the pomegranates under drought stress with exogenous ABA of different concentrations (30, 60 and 90 μM) and found that, compared to those without treatment, ABA can improve pomegranate's growth condition and related physiological responding processes. We also performed comparative transcriptome analysis between the ABA-treated and untreated pomegranates to reveal the ABA-induced mechanisms in response to drought-stress. Our results showed that exogenous ABA application substantially enhanced pomegranate drought resistance by strengthening some metabolic pathways, such as brassinosteroid synthesis, peroxisome biogenesis, photosynthesis and hemicelluloses synthesis. Furthermore, the over-dose treatment of exogenous ABA was found to trigger ABA degradation process and a feedback loop in pomegranate to balances the ABA accumulation that exceeds the optimal ABA requirement, at the cost of suppressed growth process and stress resistance. Our findings provide new insights into the molecular regulation mechanisms underlying the ABA-mediated drought-stress resistance in pomegranates.
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Affiliation(s)
- Jingjing Qian
- Anhui Science and Technology University, Fengyang, Anhui, 233100, China
| | - Xueping Zhang
- Anhui Science and Technology University, Fengyang, Anhui, 233100, China
| | - Yan Yan
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ning Wang
- Huaiyuan China-Israel Agro-Tech Co., Ltd., Bengbu, Anhui, 233400, China
| | - Weiqiang Ge
- Huaiyuan China-Israel Agro-Tech Co., Ltd., Bengbu, Anhui, 233400, China
| | - Qian Zhou
- Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
| | - Yuchen Yang
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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14
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Munir S, Mumtaz MA, Ahiakpa JK, Liu G, Chen W, Zhou G, Zheng W, Ye Z, Zhang Y. Genome-wide analysis of Myo-inositol oxygenase gene family in tomato reveals their involvement in ascorbic acid accumulation. BMC Genomics 2020; 21:284. [PMID: 32252624 PMCID: PMC7132880 DOI: 10.1186/s12864-020-6708-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/30/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Ascorbic acid (Vitamin C, AsA) is an antioxidant metabolite involved in plant development and environmental stimuli. AsA biosynthesis has been well studied in plants, and MIOX is a critical enzyme in plants AsA biosynthesis pathway. However, Myo-inositol oxygenase (MIOX) gene family members and their involvement in AsA biosynthesis and response to abiotic stress remain unclear. RESULTS In this study, five tomato genes encoding MIOX proteins and possessing MIOX motifs were identified. Structural analysis and distribution mapping showed that 5 MIOX genes contain different intron/exon patterns and unevenly distributed among four chromosomes. Besides, expression analyses indicated the remarkable expression of SlMIOX genes in different plant tissues. Furthermore, transgenic lines were obtained by over-expression of the MIOX4 gene in tomato. The overexpression lines showed a significant increase in total ascorbate in leaves and red fruits compared to control. Expression analysis revealed that increased accumulation of AsA in MIOX4 overexpression lines is possible as a consequence of the multiple genes involved in AsA biosynthesis. Myo inositol (MI) feeding in leaf and fruit implied that the Myo-inositol pathway improved the AsA biosynthesis in leaves and fruits. MIOX4 overexpression lines exhibited a better light response, abiotic stress tolerance, and AsA biosynthesis capacity. CONCLUSIONS These results showed that MIOX4 transgenic lines contribute to AsA biosynthesis, evident as better light response and improved oxidative stress tolerance. This study provides the first comprehensive analysis of the MIOX gene family and their involvement in ascorbate biosynthesis in tomato.
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Affiliation(s)
- Shoaib Munir
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Muhammad Ali Mumtaz
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - John Kojo Ahiakpa
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Genzhong Liu
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Weifang Chen
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Guolin Zhou
- Wuhan Academy of Agricultural Sciences, Wuhan, 430065, China
| | - Wei Zheng
- HZAU Chuwei Institute of Advanced Seeds, Wuhan, 430070, China
| | - Zhibiao Ye
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
- HZAU Chuwei Institute of Advanced Seeds, Wuhan, 430070, China
| | - Yuyang Zhang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China.
- HZAU Chuwei Institute of Advanced Seeds, Wuhan, 430070, China.
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15
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Vitamin C in Plants: From Functions to Biofortification. Antioxidants (Basel) 2019; 8:antiox8110519. [PMID: 31671820 PMCID: PMC6912510 DOI: 10.3390/antiox8110519] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/25/2019] [Accepted: 10/26/2019] [Indexed: 12/18/2022] Open
Abstract
Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is also a cofactor for numerous enzymes involved in plant and human metabolism. In humans, vitamin C takes part in various physiological processes, such as iron absorption, collagen synthesis, immune stimulation, and epigenetic regulation. Due to the functional loss of the gene coding for l-gulonolactone oxidase, humans cannot synthesize vitamin C; thus, they principally utilize plant-based foods for their needs. For this reason, increasing the vitamin C content of crops could have helpful effects on human health. To achieve this objective, exhaustive knowledge of the metabolism and functions of vitamin C in plants is needed. In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed. Finally, attention is paid to the strategies that have been used to increase the content of vitamin C in crops, emphasizing not only the improvement of nutritional value of the crops but also the acquisition of plant stress resistance.
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16
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Nepal N, Yactayo‐Chang JP, Medina‐Jiménez K, Acosta‐Gamboa LM, González‐Romero ME, Arteaga‐Vázquez MA, Lorence A. Mechanisms underlying the enhanced biomass and abiotic stress tolerance phenotype of an Arabidopsis MIOX over-expresser. PLANT DIRECT 2019; 3:e00165. [PMID: 31497751 PMCID: PMC6718051 DOI: 10.1002/pld3.165] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 07/11/2019] [Accepted: 08/10/2019] [Indexed: 05/07/2023]
Abstract
Myo-inositol oxygenase (MIOX) is the first enzyme in the inositol route to ascorbate (L-ascorbic acid, AsA, vitamin C). We have previously shown that Arabidopsis plants constitutively expressing MIOX have elevated foliar AsA content and displayed enhanced growth rate, biomass accumulation, and increased tolerance to multiple abiotic stresses. In this work, we used a combination of transcriptomics, chromatography, microscopy, and physiological measurements to gain a deeper understanding of the underlying mechanisms mediating the phenotype of the AtMIOX4 line. Transcriptomic analysis revealed increased expression of genes involved in auxin synthesis, hydrolysis, transport, and metabolism, which are supported by elevated auxin levels both in vitro and in vivo, and confirmed by assays demonstrating their effect on epidermal cell elongation in the AtMIOX4 over-expressers. Additionally, we detected up-regulation of transcripts involved in photosynthesis and this was validated by increased efficiency of the photosystem II and proton motive force. We also found increased expression of amylase leading to higher intracellular glucose levels. Multiple gene families conferring plants tolerance/expressed in response to cold, water limitation, and heat stresses were found to be elevated in the AtMIOX4 line. Interestingly, the high AsA plants also displayed up-regulation of transcripts and hormones involved in defense including jasmonates, defensin, glucosinolates, and transcription factors that are known to be important for biotic stress tolerance. These results overall indicate that elevated levels of auxin and glucose, and enhanced photosynthetic efficiency in combination with up-regulation of abiotic stresses response genes underly the higher growth rate and abiotic stresses tolerance phenotype of the AtMIOX4 over-expressers.
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Affiliation(s)
- Nirman Nepal
- Arkansas Biosciences InstituteArkansas State UniversityState UniversityARUSA
| | | | - Karina Medina‐Jiménez
- Arkansas Biosciences InstituteArkansas State UniversityState UniversityARUSA
- INBIOTECAUniversidad VeracruzanaXalapaMéxico
| | | | | | | | - Argelia Lorence
- Arkansas Biosciences InstituteArkansas State UniversityState UniversityARUSA
- Department of Chemistry and PhysicsArkansas State UniversityState UniversityARUSA
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17
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Fenech M, Amaya I, Valpuesta V, Botella MA. Vitamin C Content in Fruits: Biosynthesis and Regulation. FRONTIERS IN PLANT SCIENCE 2019; 9:2006. [PMID: 30733729 PMCID: PMC6353827 DOI: 10.3389/fpls.2018.02006] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 12/31/2018] [Indexed: 05/19/2023]
Abstract
Throughout evolution, a number of animals including humans have lost the ability to synthesize ascorbic acid (ascorbate, vitamin C), an essential molecule in the physiology of animals and plants. In addition to its main role as an antioxidant and cofactor in redox reactions, recent reports have shown an important role of ascorbate in the activation of epigenetic mechanisms controlling cell differentiation, dysregulation of which can lead to the development of certain types of cancer. Although fruits and vegetables constitute the main source of ascorbate in the human diet, rising its content has not been a major breeding goal, despite the large inter- and intraspecific variation in ascorbate content in fruit crops. Nowadays, there is an increasing interest to boost ascorbate content, not only to improve fruit quality but also to generate crops with elevated stress tolerance. Several attempts to increase ascorbate in fruits have achieved fairly good results but, in some cases, detrimental effects in fruit development also occur, likely due to the interaction between the biosynthesis of ascorbate and components of the cell wall. Plants synthesize ascorbate de novo mainly through the Smirnoff-Wheeler pathway, the dominant pathway in photosynthetic tissues. Two intermediates of the Smirnoff-Wheeler pathway, GDP-D-mannose and GDP-L-galactose, are also precursors of the non-cellulosic components of the plant cell wall. Therefore, a better understanding of ascorbate biosynthesis and regulation is essential for generation of improved fruits without developmental side effects. This is likely to involve a yet unknown tight regulation enabling plant growth and development, without impairing the cell redox state modulated by ascorbate pool. In certain fruits and developmental conditions, an alternative pathway from D-galacturonate might be also relevant. We here review the regulation of ascorbate synthesis, its close connection with the cell wall, as well as different strategies to increase its content in plants, with a special focus on fruits.
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Affiliation(s)
- Mario Fenech
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea (IHSM), Consejo Superior de Investigaciones Científicas, Universidad de Málaga, Málaga, Spain
| | - Iraida Amaya
- Instituto Andaluz de Investigación y Formación Agraria y Pesquera, Area de Genómica y Biotecnología, Centro de Málaga, Spain
| | - Victoriano Valpuesta
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea (IHSM), Consejo Superior de Investigaciones Científicas, Universidad de Málaga, Málaga, Spain
| | - Miguel A. Botella
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea (IHSM), Consejo Superior de Investigaciones Científicas, Universidad de Málaga, Málaga, Spain
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18
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Ivanov Kavkova E, Blöchl C, Tenhaken R. The Myo-inositol pathway does not contribute to ascorbic acid synthesis. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21 Suppl 1:95-102. [PMID: 30102814 PMCID: PMC6492119 DOI: 10.1111/plb.12898] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/07/2018] [Indexed: 05/07/2023]
Abstract
Ascorbic acid (AsA) biosynthesis in plants predominantly occurs via a pathway with d-mannose and l-galactose as intermediates. One alternative pathway for AsA synthesis, which is similar to the biosynthesis route in mammals, is controversially discussed for plants. Here, myo-inositol is cleaved to glucuronic acid and then converted via l-gulonate to AsA. In contrast to animals, plants have an effective recycling pathway for glucuronic acid, being a competitor for the metabolic rate. Recycling involves a phosphorylation at C1 by the enzyme glucuronokinase. Two previously described T-DNA insertion lines in the gene coding for glucuronokinase1 show wild type-like expression levels of the mRNA in our experiments and do not accumulate glucuronic acid in labelling experiments disproving that these lines are true knockouts. As suitable T-DNA insertion lines were not available, we generated frameshift mutations in the major expressed isoform glucuronokinase1 (At3g01640) to potentially redirect metabolites to AsA. However, radiotracer experiments with 3 H-myo-inositol revealed that the mutants in glucuronokinase1 accumulate only glucuronic acid and incorporate less metabolite into cell wall polymers. AsA was not labelled, suggesting that Arabidopsis cannot efficiently use glucuronic acid for AsA biosynthesis. All four mutants in glucuronokinase as well as the wild type have the same level of AsA in leaves.
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Affiliation(s)
| | - C. Blöchl
- Department of BiosciencesUniversity of SalzburgSalzburgAustria
| | - R. Tenhaken
- Department of BiosciencesUniversity of SalzburgSalzburgAustria
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19
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Macknight RC, Laing WA, Bulley SM, Broad RC, Johnson AA, Hellens RP. Increasing ascorbate levels in crops to enhance human nutrition and plant abiotic stress tolerance. Curr Opin Biotechnol 2017; 44:153-160. [PMID: 28231513 DOI: 10.1016/j.copbio.2017.01.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/29/2017] [Accepted: 01/30/2017] [Indexed: 12/20/2022]
Abstract
Ascorbate (or vitamin C) is an essential human micronutrient predominantly obtained from plants. In addition to preventing scurvy, it is now known to have broader roles in human health, for example as a cofactor for enzymes involved in epigenetic programming and as regulator of cellular iron uptake. Furthermore, ascorbate is the major antioxidant in plants and underpins many environmentally induced abiotic stress responses. Biotechnological approaches to enhance the ascorbate content of crops therefore have potential to improve both human health and abiotic stress tolerance of crops. Identifying the genetic basis of ascorbate variation between plant varieties and discovering how some 'super fruits' accumulate extremely high levels of ascorbate should reveal new ways to more effectively manipulate the production of ascorbate in crops.
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Affiliation(s)
- Richard C Macknight
- University of Otago, Department of Biochemistry, PO Box 56, Dunedin 9054, New Zealand; Queensland University of Technology, Centre for Tropical Crops and Biocommodities, Institute for Future Environments, GPO Box 2434, Brisbane, QLD 4001, Australia.
| | - William A Laing
- The New Zealand Institute for Plant & Food Research Limited, Food Industry Science Centre, Bachelor Road, Palmerston North 4474, New Zealand
| | - Sean M Bulley
- The New Zealand Institute for Plant & Food Research Limited, 412 No 1 Road, RD 2, Te Puke 3182, New Zealand
| | - Ronan C Broad
- The University of Melbourne, School of BioSciences, Parkville, Melbourne, 3010 VIC, Australia
| | - Alexander At Johnson
- The University of Melbourne, School of BioSciences, Parkville, Melbourne, 3010 VIC, Australia
| | - Roger P Hellens
- Queensland University of Technology, Centre for Tropical Crops and Biocommodities, Institute for Future Environments, GPO Box 2434, Brisbane, QLD 4001, Australia
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20
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Schultz ER, Zupanska AK, Sng NJ, Paul AL, Ferl RJ. Skewing in Arabidopsis roots involves disparate environmental signaling pathways. BMC PLANT BIOLOGY 2017; 17:31. [PMID: 28143395 PMCID: PMC5286820 DOI: 10.1186/s12870-017-0975-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 01/12/2017] [Indexed: 05/20/2023]
Abstract
BACKGROUND Skewing root patterns provide key insights into root growth strategies and mechanisms that produce root architectures. Roots exhibit skewing and waving when grown on a tilted, impenetrable surface. The genetics guiding these morphologies have been examined, revealing that some Arabidopsis ecotypes skew and wave (e.g. WS), while others skew insignificantly but still wave (e.g. Col-0). The underlying molecular mechanisms of skewing and waving remain unclear. In this study, transcriptome data were derived from two Arabidopsis ecotypes, WS and Col-0, under three tilted growth conditions in order to identify candidate genes involved in skewing. RESULTS This work identifies a number of genes that are likely involved in skewing, using growth conditions that differentially affect skewing and waving. Comparing the gene expression profiles of WS and Col-0 in different tilted growth conditions identified 11 candidate genes as potentially involved in the control of skewing. These 11 genes are involved in several different cellular processes, including sugar transport, salt signaling, cell wall organization, and hormone signaling. CONCLUSIONS This study identified 11 genes whose change in expression level is associated with root skewing behavior. These genes are involved in signaling and perception, rather than the physical restructuring of root. Future work is needed to elucidate the potential role of these candidate genes during root skewing.
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Affiliation(s)
- Eric R. Schultz
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611 USA
- Present address: Department of Biology, Washington University in St. Louis, St. Louis, MO 63130 USA
| | - Agata K. Zupanska
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611 USA
| | - Natasha J. Sng
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611 USA
| | - Anna-Lisa Paul
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611 USA
| | - Robert J. Ferl
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611 USA
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL 32610 USA
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21
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Pauly M, Keegstra K. Biosynthesis of the Plant Cell Wall Matrix Polysaccharide Xyloglucan. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:235-59. [PMID: 26927904 DOI: 10.1146/annurev-arplant-043015-112222] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Xyloglucan (XyG) is a matrix polysaccharide that is present in the cell walls of all land plants. It consists of a β-1,4-linked glucan backbone that is further substituted with xylosyl residues. These xylosyl residues can be further substituted with other glycosyl and nonglycosyl substituents that vary depending on the plant family and specific tissue. Advances in plant mutant isolation and characterization, functional genomics, and DNA sequencing have led to the identification of nearly all transferases and synthases necessary to synthesize XyG. Thus, in terms of the molecular mechanisms of plant cell wall polysaccharide biosynthesis, XyG is the most well understood. However, much remains to be learned about the molecular mechanisms of polysaccharide assembly and the regulation of these processes. Knowledge of the XyG biosynthetic machinery allows the XyG structure to be tailored in planta to ascertain the functions of this polysaccharide and its substituents in plant growth and interactions with the environment.
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Affiliation(s)
- Markus Pauly
- Department of Plant Cell Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany;
| | - Kenneth Keegstra
- DOE Great Lakes Bioenergy Research Center, DOE Plant Research Laboratory, and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
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22
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Qin H, Deng Z, Zhang C, Wang Y, Wang J, Liu H, Zhang Z, Huang R, Zhang Z. Rice GDP-mannose pyrophosphorylase OsVTC1-1 and OsVTC1-3 play different roles in ascorbic acid synthesis. PLANT MOLECULAR BIOLOGY 2016; 90:317-27. [PMID: 26715595 DOI: 10.1007/s11103-015-0420-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 12/09/2015] [Indexed: 05/12/2023]
Abstract
GDP-D-mannose pyrophosphorylase (GMPase) catalyzes the synthesis of GDP-D-mannose, which is a precursor for ascorbic acid (AsA) synthesis in plants. The rice genome encodes three GMPase homologs OsVTC1-1, OsVTC1-3 and OsVTC1-8, but their roles in AsA synthesis are unclear. The overexpression of OsVTC1-1 or OsVTC1-3 restored the AsA synthesis of vtc1-1 in Arabidopsis, while that of OsVTC1-8 did not, indicating that only OsVTC1-1 and OsVTC1-3 are involved in AsA synthesis in rice. Similar to Arabidopsis VTC1, the expression of OsVTC1-1 was high in leaves, induced by light, and inhibited by dark. Unlike OsVTC1-1, the expression level of OsVTC1-3 was high in roots and quickly induced by the dark, while the transcription level of OsVTC1-8 did not show obvious changes under constant light or dark treatments. In OsVTC1-1 RNAi plants, the AsA content of rice leaves decreased, and the AsA production induced by light was limited. In contrast, OsVTC1-3 RNAi lines altered AsA synthesis levels in rice roots, but not in the leaves or under the light/dark treatment. The enzyme activity showed that OsVTC1-1 and OsVTC1-3 had higher GMPase activities than OsVTC1-8 in vitro. Our data showed that, unlike in Arabidopsis, the rice GPMase homologous proteins illustrated a new model in AsA synthesis: OsVTC1-1 may be involved in the AsA synthesis, which takes place in leaves, while OsVTC1-3 may be responsible for AsA synthesis in roots. The different roles of rice GMPase homologous proteins in AsA synthesis may be due to their differences in transcript levels and enzyme activities.
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Affiliation(s)
- Hua Qin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, 100081, China
| | - Zaian Deng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Hainan Academy of Agricultural Sciences, Haikou, 571000, China
| | - Chuanyu Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Hainan Academy of Agricultural Sciences, Haikou, 571000, China
| | - Yayun Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, 100081, China
| | - Juan Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, 100081, China
| | - Hai Liu
- Department of Biology, University of Virginia, Charlottesville, VA, 22903, USA
| | - Zhili Zhang
- Hainan Academy of Agricultural Sciences, Haikou, 571000, China
| | - Rongfeng Huang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, 100081, China.
| | - Zhijin Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, 100081, China.
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23
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Warth B, Siegwart G, Lemmens M, Krska R, Adam G, Schuhmacher R. Hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry for the quantification of uridine diphosphate-glucose, uridine diphosphate-glucuronic acid, deoxynivalenol and its glucoside: In-house validation and application to wheat. J Chromatogr A 2015; 1423:183-9. [PMID: 26554298 DOI: 10.1016/j.chroma.2015.10.070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 10/16/2015] [Accepted: 10/22/2015] [Indexed: 11/17/2022]
Abstract
Nucleotide sugars, the activated forms of monosaccharides, are important metabolites involved in a multitude of cellular processes including glycosylation of xenobiotics. Especially in plants, UDP-glucose is one of the most prominent members among these nucleotide-sugars, as it is involved in the formation of glucose conjugates of xenobiotics, including mycotoxins, but also holds a central role in the interconversion of energized sugars such as the formation of UDP-glucuronic acid required for cell wall biosynthesis. Here, we present the first HILIC-LC-ESI-TQ-MS/MS method for the quantification of UDP-glucose and UDP-glucuronic acid together with the Fusarium toxin deoxynivalenol (DON) and its major plant detoxification product DON-3-O-glucoside (DON-3-Glc) utilizing a polymer-based column. For sample preparation a time-effective and straightforward 'dilute and shoot' protocol was applied. The chromatographic run time was minimized to 9min including proper column re-equilibration. In-house validation of the method verified its linear range, intra- (1-7%) and interday (8-20%) precision, instrumental LODs between 0.6 and 10ngmL(-1), selectivity and moderate matrix effects with mean recoveries of 85-103%. To prove the methods applicability, we analyzed two sets of wheat extracts obtained from different cultivars grown under standardized greenhouse conditions. The results clearly demonstrated the suitability of the developed method to quantify UDP-glucose, DON and its masked form D3G in diluted wheat extracts. We observed differing concentration levels of UDP-glucose in the two wheat cultivars showing different resistance to the severe plant disease Fusarium head blight. We propose that the higher ability to detoxify DON into DON-3-Glc might be a consequence of the higher cellular UDP-glucose pool in the resistant cultivar.
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Affiliation(s)
- Benedikt Warth
- Center for Analytical Chemistry, Department for Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 20, A-3430 Tulln, Austria
| | - Gerald Siegwart
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 24, 3430 Tulln, Austria
| | - Marc Lemmens
- Institute for Biotechnology in Plant Production, Department for Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 20, A-3430 Tulln, Austria
| | - Rudolf Krska
- Center for Analytical Chemistry, Department for Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 20, A-3430 Tulln, Austria
| | - Gerhard Adam
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 24, 3430 Tulln, Austria
| | - Rainer Schuhmacher
- Center for Analytical Chemistry, Department for Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 20, A-3430 Tulln, Austria.
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Chen C, Sun X, Duanmu H, Yu Y, Liu A, Xiao J, Zhu Y. Ectopic Expression of a Glycine soja myo-Inositol Oxygenase Gene (GsMIOX1a) in Arabidopsis Enhances Tolerance to Alkaline Stress. PLoS One 2015; 10:e0129998. [PMID: 26091094 PMCID: PMC4474918 DOI: 10.1371/journal.pone.0129998] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 05/16/2015] [Indexed: 02/04/2023] Open
Abstract
Myo-inositol participates in various aspects of plant physiology, and myo-inositol oxygenase is the key enzyme of the myo-inositol oxygenation pathway. Previous studies indicated that myo-inositol oxygenase may play a role in plant responses to abiotic stresses. In this study, we focused on the functional characterization of GsMIOX1a, a remarkable alkaline stress-responsive gene of Glycine soja 07256, based on RNA-seq data. Using quantitative real-time PCR, we demonstrated that GsMIOX1a is rapidly induced by alkaline stress and expressed predominantly in flowers. We also elucidated the positive function of GsMIOX1a in the alkaline response in the wild type, atmiox1 mutant as well as GsMIOX1a-overexpressing Arabidopsis. We determined that atmiox1 mutant decreased Arabidopsis tolerance to alkaline stress, whereas GsMIOX1a overexpression increased tolerance. Moreover, the expression levels of some alkaline stress-responsive and inducible marker genes, including H+-Ppase, NADP-ME, KIN1 and RD29B, were also up-regulated in GsMIOX1a overexpression lines compared with the wild type and atmiox1 mutant. Together, these results suggest that the GsMIOX1a gene positively regulates plant tolerance to alkaline stress. This is the first report to demonstrate that ectopic expression of myo-inositol oxygenase improves alkaline tolerance in plants.
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Affiliation(s)
- Chen Chen
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
| | - Xiaoli Sun
- Agronomy College, Heilongjiang Bayi Agricultural University, Daqing, 163319, P.R. China
| | - Huizi Duanmu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
| | - Yang Yu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
| | - Ailin Liu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
| | - Jialei Xiao
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
| | - Yanming Zhu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030, P.R. China
- * E-mail:
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Jaouannet M, Morris JA, Hedley PE, Bos JIB. Characterization of Arabidopsis Transcriptional Responses to Different Aphid Species Reveals Genes that Contribute to Host Susceptibility and Non-host Resistance. PLoS Pathog 2015; 11:e1004918. [PMID: 25993686 PMCID: PMC4439036 DOI: 10.1371/journal.ppat.1004918] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/27/2015] [Indexed: 11/26/2022] Open
Abstract
Aphids are economically important pests that display exceptional variation in host range. The determinants of diverse aphid host ranges are not well understood, but it is likely that molecular interactions are involved. With significant progress being made towards understanding host responses upon aphid attack, the mechanisms underlying non-host resistance remain to be elucidated. Here, we investigated and compared Arabidopsis thaliana host and non-host responses to aphids at the transcriptional level using three different aphid species, Myzus persicae, Myzus cerasi and Rhopalosiphum pisum. Gene expression analyses revealed a high level of overlap in the overall gene expression changes during the host and non-host interactions with regards to the sets of genes differentially expressed and the direction of expression changes. Despite this overlap in transcriptional responses across interactions, there was a stronger repression of genes involved in metabolism and oxidative responses specifically during the host interaction with M. persicae. In addition, we identified a set of genes with opposite gene expression patterns during the host versus non-host interactions. Aphid performance assays on Arabidopsis mutants that were selected based on our transcriptome analyses identified novel genes contributing to host susceptibility, host defences during interactions with M. persicae as well to non-host resistance against R. padi. Understanding how plants respond to aphid species that differ in their ability to infest plant species, and identifying the genes and signaling pathways involved, is essential for the development of novel and durable aphid control in crop plants. Aphids are phloem-feeding insects that cause feeding damage and transmit plant viruses to many crops. While most aphid species are restricted to one or few host plants, some aphids can infest a wide range of plant species. These insects spend a considerable time on non-hosts, where they probe the leaf tissue and secrete saliva, but for unknown reasons are unable to ingest phloem sap. This suggests that aphids interact with non-host plants at the molecular level, but potentially do not suppress plant defences and/or promote the release of nutrients. We compared gene expression of plants during host and non-host interactions with aphids to identify genes involved in immunity. We found significant overlap in the plant responses to aphids regardless of the type of interaction. Despite this, we identified a set of genes specifically affected during host or non-host interactions with specific aphid species. In addition, we showed that several of these genes contribute to host and/or non-host immunity. These findings are important, as they advance our understanding of the plant cellular processes involved in host and non-host responses against insect pests. Understanding mechanisms of host and non-host resistance to plant parasites is essential for development of novel control strategies.
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Affiliation(s)
- Maëlle Jaouannet
- Cell and Molecular Sciences, The James Hutton Institute, Dundee, United Kingdom
- Dundee Effector Consortium, Dundee, United Kingdom
| | - Jenny A. Morris
- Cell and Molecular Sciences, The James Hutton Institute, Dundee, United Kingdom
| | - Peter E. Hedley
- Cell and Molecular Sciences, The James Hutton Institute, Dundee, United Kingdom
| | - Jorunn I. B. Bos
- Cell and Molecular Sciences, The James Hutton Institute, Dundee, United Kingdom
- Dundee Effector Consortium, Dundee, United Kingdom
- Division of Plant Sciences, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail:
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Transcriptome analysis of canola (Brassica napus) under salt stress at the germination stage. PLoS One 2015; 10:e0116217. [PMID: 25679513 PMCID: PMC4332669 DOI: 10.1371/journal.pone.0116217] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 12/05/2014] [Indexed: 11/19/2022] Open
Abstract
Canola (Brassica napus) is one of the most important oil crops in the world. However, its yield has been constrained by salt stress. In this study, transcriptome profiles were explored using Digital Gene Expression (DGE) at 0, 3, 12 and 24 hours after H2O (control) and NaCl treatments on B. napus roots at the germination stage. Comparisons of gene-expression between the control and the treatment were conducted after tag-mapping to the sequenced Brassica rapa genome. The differentially expressed genes during the time course of salt stress were focused on, and 163 genes were identified to be differentially expressed at all the time points. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that some of the genes were involved in proline metabolism, inositol metabolism, carbohydrate metabolic processes and oxidation-reduction processes and may play vital roles in the salt-stress response at the germination stage. Thus, this study provides new candidate salt stress responding genes, which may function in novel putative nodes in the molecular pathways of salt stress resistance.
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Contrasting metabolism in perenniating structures of upland and lowland switchgrass plants late in the growing season. PLoS One 2014; 9:e105138. [PMID: 25133804 PMCID: PMC4136849 DOI: 10.1371/journal.pone.0105138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 07/17/2014] [Indexed: 12/24/2022] Open
Abstract
Background Switchgrass (Panicum virgatum L.) is being developed as a bioenergy crop for many temperate regions of the world. One way to increase biomass yields is to move southern adapted lowland cultivars to more northern latitudes. However, many southerly adapted switchgrass germplasm can suffer significant winter kill in northerly climes. Materials and Methods Here, we have applied next-generation sequencing in combination with biochemical analyses to query the metabolism of crowns and rhizomes obtained from two contrasting switchgrass cultivars. Crowns and rhizomes from field-grown lowland (cv Kanlow) and upland (cv Summer) switchgrass cultivars were collected from three randomly selected post-flowering plants. Summer plants were senescing, whereas Kanlow plants were not at this harvest date. Results Principal component analysis (PCA) differentiated between both the Summer and Kanlow transcriptomes and metabolomes. Significant differences in transcript abundances were detected for 8,050 genes, including transcription factors such as WRKYs and those associated with phenylpropanoid biosynthesis. Gene-set enrichment analyses showed that a number of pathways were differentially up-regulated in the two populations. For both populations, protein levels and enzyme activities agreed well with transcript abundances for genes involved in the phenylpropanoid pathway that were up-regulated in Kanlow crowns and rhizomes. The combination of these datasets suggests that dormancy-related mechanisms had been triggered in the crowns and rhizomes of the Summer plants, whereas the crowns and rhizomes of Kanlow plants had yet to enter dormancy. Conclusions Delayed establishment of dormancy at more northerly latitudes could be one factor that reduces winter-survival in the high-yielding Kanlow plants. Understanding the cellular signatures that accompany the transition to dormancy can be used in the future to select plants with improved winter hardiness.
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Siddique S, Endres S, Sobczak M, Radakovic ZS, Fragner L, Grundler FMW, Weckwerth W, Tenhaken R, Bohlmann H. Myo-inositol oxygenase is important for the removal of excess myo-inositol from syncytia induced by Heterodera schachtii in Arabidopsis roots. THE NEW PHYTOLOGIST 2014; 201:476-485. [PMID: 24117492 PMCID: PMC4285123 DOI: 10.1111/nph.12535] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 08/21/2013] [Indexed: 05/23/2023]
Abstract
The enzyme myo-inositol oxygenase is the key enzyme of a pathway leading from myo-inositol to UDP-glucuronic acid. In Arabidopsis, myo-inositol oxygenase is encoded by four genes. All genes are strongly expressed in syncytia induced by the beet cyst nematode Heterodera schachtii in Arabidopsis roots. Here, we studied the effect of a quadruple myo-inositol oxygenase mutant on nematode development. We performed metabolite profiling of syncytia induced in roots of the myo-inositol oxygenase quadruple mutant. The role of galactinol in syncytia was studied using Arabidopsis lines with elevated galactinol levels and by supplying galactinol to wild-type seedlings. The quadruple myo-inositol oxygenase mutant showed a significant reduction in susceptibility to H. schachtii, and syncytia had elevated myo-inositol and galactinol levels and an elevated expression level of the antimicrobial thionin gene Thi2.1. This reduction in susceptibility could also be achieved by exogenous application of galactinol to wild-type seedlings. The primary function of myo-inositol oxygenase for syncytium development is probably not the production of UDP-glucuronic acid as a precursor for cell wall polysaccharides, but the reduction of myo-inositol levels and thereby a reduction in the galactinol level to avoid the induction of defence-related genes.
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Affiliation(s)
- Shahid Siddique
- Division of Plant Protection, Department of Crop
Sciences, University of Natural Resources and Life SciencesA-1019, Vienna, Austria
| | - Stefanie Endres
- Plant Physiology, University of SalzburgHellbrunnerstr. 34, A-5020, Salzburg, Austria
| | - Miroslaw Sobczak
- Department of Botany, Warsaw University of Life Sciences
(SGGW)02-787, Warsaw, Poland
| | - Zoran S Radakovic
- INRES, Department of Molecular Phytomedicine, University
of BonnKarlrobert–Kreiten–Str. 13, 53115, Bonn, Germany
| | - Lena Fragner
- Department of Molecular Systems Biology, University of
ViennaA-1090, Vienna, Austria
| | - Florian M W Grundler
- INRES, Department of Molecular Phytomedicine, University
of BonnKarlrobert–Kreiten–Str. 13, 53115, Bonn, Germany
| | - Wolfram Weckwerth
- Department of Molecular Systems Biology, University of
ViennaA-1090, Vienna, Austria
| | - Raimund Tenhaken
- Plant Physiology, University of SalzburgHellbrunnerstr. 34, A-5020, Salzburg, Austria
| | - Holger Bohlmann
- Division of Plant Protection, Department of Crop
Sciences, University of Natural Resources and Life SciencesA-1019, Vienna, Austria
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Lisko KA, Torres R, Harris RS, Belisle M, Vaughan MM, Jullian B, Chevone BI, Mendes P, Nessler CL, Lorence A. Elevating vitamin C content via overexpression of myo-inositol oxygenase and l-gulono-1,4-lactone oxidase in Arabidopsis leads to enhanced biomass and tolerance to abiotic stresses. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY. PLANT : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 2013; 49:643-655. [PMID: 25767369 PMCID: PMC4354779 DOI: 10.1007/s11627-013-9568-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
l-Ascorbic acid (vitamin C) is an abundant metabolite in plant cells and tissues. Ascorbate functions as an antioxidant, as an enzyme cofactor, and plays essential roles in multiple physiological processes including photosynthesis, photoprotection, control of cell cycle and cell elongation, and modulation of flowering time, gene regulation, and senescence. The importance of this key molecule in regulating whole plant morphology, cell structure, and plant development has been clearly established via characterization of low vitamin C mutants of Arabidopsis, potato, tobacco, tomato, and rice. However, the consequences of elevating ascorbate content in plant growth and development are poorly understood. Here we demonstrate that Arabidopsis lines over-expressing a myo-inositol oxygenase or an l-gulono-1,4-lactone oxidase, containing elevated ascorbate, display enhanced growth and biomass accumulation of both aerial and root tissues. To our knowledge this is the first study demonstrating such a marked positive effect in plant growth in lines engineered to contain elevated vitamin C content. In addition, we present evidence showing that these lines are tolerant to a wide range of abiotic stresses including salt, cold, and heat. Total ascorbate content of the transgenic lines remained higher than those of controls under the abiotic stresses tested. Interestingly, exposure to pyrene, a polycyclic aromatic hydrocarbon and known inducer of oxidative stress in plants, leads to stunted growth of the aerial tissue, reduction in the number of root hairs, and inhibition of leaf expansion in wild type plants, while these symptoms are less severe in the over-expressers. Our results indicate the potential of this metabolic engineering strategy to develop crops with enhanced biomass, abiotic stress tolerance, and phytoremediation capabilities.
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Affiliation(s)
- Katherine A Lisko
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
| | - Raquel Torres
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
| | - Rodney S Harris
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
| | - Melinda Belisle
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
- Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280, USA
| | - Martha M Vaughan
- Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Berangère Jullian
- Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Boris I Chevone
- Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Pedro Mendes
- Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Craig L Nessler
- Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Argelia Lorence
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
- Department of Chemistry and Physics, Arkansas State University, P.O. Box 419, State University, AR 72467, USA
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Geserick C, Tenhaken R. UDP-sugar pyrophosphorylase is essential for arabinose and xylose recycling, and is required during vegetative and reproductive growth in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:239-47. [PMID: 23373795 PMCID: PMC3659416 DOI: 10.1111/tpj.12116] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/04/2013] [Indexed: 05/20/2023]
Abstract
Numerous nucleotide sugars are needed in plants to synthesize cell wall polymers and glycoproteins. The de novo synthesis of nucleotide sugars is of major importance. During growth, however, some polymers are broken down to monosaccharides. Reactivation of these sugars into nucleotide sugars occurs in two steps: first, by a substrate-specific sugar-1-kinase and, second, by UDP-sugar-pyrophosphorylase (USP), which has broad substrate specificity. A knock-out of the USP gene results in non-fertile pollen. By using various genetic complementation approaches we obtained a strong (>95%) knock-down line in USP that allowed us to investigate the physiological role of the enzyme during the life cycle. Mutant plants show an arabinose reduction in the cell wall, and accumulate mainly two sugars, arabinose and xylose, in the cytoplasm. The arabinogalactanproteins in usp mutants show no significant reduction in size. USP is also part of the myo-inositol oxygenation pathway to UDP-glucuronic acid; however, free glucuronic acid does not accumulate in cells, suggesting alternative conversion pathways of this monosaccharide. The knock-down plants are mostly sterile because of the improper formation of anthers and pollen sacks.
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Geserick C, Tenhaken R. UDP-sugar pyrophosphorylase is essential for arabinose and xylose recycling, and is required during vegetative and reproductive growth in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013. [PMID: 23373795 DOI: 10.1111/tpj.2013.74.issue-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Numerous nucleotide sugars are needed in plants to synthesize cell wall polymers and glycoproteins. The de novo synthesis of nucleotide sugars is of major importance. During growth, however, some polymers are broken down to monosaccharides. Reactivation of these sugars into nucleotide sugars occurs in two steps: first, by a substrate-specific sugar-1-kinase and, second, by UDP-sugar-pyrophosphorylase (USP), which has broad substrate specificity. A knock-out of the USP gene results in non-fertile pollen. By using various genetic complementation approaches we obtained a strong (>95%) knock-down line in USP that allowed us to investigate the physiological role of the enzyme during the life cycle. Mutant plants show an arabinose reduction in the cell wall, and accumulate mainly two sugars, arabinose and xylose, in the cytoplasm. The arabinogalactanproteins in usp mutants show no significant reduction in size. USP is also part of the myo-inositol oxygenation pathway to UDP-glucuronic acid; however, free glucuronic acid does not accumulate in cells, suggesting alternative conversion pathways of this monosaccharide. The knock-down plants are mostly sterile because of the improper formation of anthers and pollen sacks.
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Affiliation(s)
- Claudia Geserick
- Department Cell Biology, Plant Physiology, University of Salzburg, Hellbrunnerstr. 34, Salzburg, 5020, Austria
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Duan J, Zhang M, Zhang H, Xiong H, Liu P, Ali J, Li J, Li Z. OsMIOX, a myo-inositol oxygenase gene, improves drought tolerance through scavenging of reactive oxygen species in rice (Oryza sativa L.). PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 196:143-51. [PMID: 23017909 DOI: 10.1016/j.plantsci.2012.08.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 07/27/2012] [Accepted: 08/03/2012] [Indexed: 05/21/2023]
Abstract
Myo-inositol oxygenase (MIOX), a unique monooxygenase, catalyzes the oxidation of myo-inositol to d-glucuronic acid. However, the protective role of MIOX in plants against oxidative stress or drought stress remains unknown. In this study, the functional characterization of MIOX obtained from the cDNA library of upland rice (Oryza sativa L. cv. IRAT109), was performed. OsMIOX was expressed predominantly in the roots and induced by drought, H₂O₂, salt, cold and abscisic acid. The transgenic rice lines overexpressing OsMIOX showed obviously improved growth performance in the medium containing 200 mM mannitol. Further, the survival rate of leaves from the transgenic rice lines was significantly higher than that of the wild type plants under polyethylene glycol treatment. It was discovered that the activity of ROS-scavenging enzymes and proline content, as well as the transcript levels of many ROS scavenging genes were significantly increased in transgenic plants compared to the wild type plants under drought stress conditions. Together, these data suggest that OsMIOX has a specific function in drought stress tolerance by decreasing oxidative damage.
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Affiliation(s)
- Junzhi Duan
- Key Lab of Crop Heterosis and Utilization of Ministry of Education, Beijing Key Lab of Crop Genetic Improvement, China Agricultural University, Beijing 100193, PR China
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Siddique S, Sobczak M, Tenhaken R, Grundler FMW, Bohlmann H. Cell wall ingrowths in nematode induced syncytia require UGD2 and UGD3. PLoS One 2012; 7:e41515. [PMID: 22848518 PMCID: PMC3406070 DOI: 10.1371/journal.pone.0041515] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 06/21/2012] [Indexed: 12/15/2022] Open
Abstract
The cyst nematode Heterodera schachtii infects roots of Arabidopsis plants and establishes feeding sites called syncytia, which are the only nutrient source for nematodes. Development of syncytia is accompanied by changes in cell wall structures including the development of cell wall ingrowths. UDP-glucuronic acid is a precursor of several cell wall polysaccharides and can be produced by UDP-glucose dehydrogenase through oxidation of UDP-glucose. Four genes in Arabidopsis encode this enzyme. Promoter::GUS analysis revealed that UGD2 and UGD3 were expressed in syncytia as early as 1 dpi while expression of UGD1 and UGD4 could only be detected starting at 2 dpi. Infection assays showed no differences between Δugd1 and Δugd4 single mutants and wild type plants concerning numbers of males and females and the size of syncytia and cysts. On single mutants of Δugd2 and Δugd3, however, less and smaller females, and smaller syncytia formed compared to wild type plants. The double mutant ΔΔugd23 had a stronger effect than the single mutants. These data indicate that UGD2 and UGD3 but not UGD1 and UGD4 are important for syncytium development. We therefore studied the ultrastructure of syncytia in the ΔΔugd23 double mutant. Syncytia contained an electron translucent cytoplasm with degenerated cellular organelles and numerous small vacuoles instead of the dense cytoplasm as in syncytia developing in wild type roots. Typical cell wall ingrowths were missing in the ΔΔugd23 double mutant. Therefore we conclude that UGD2 and UGD3 are needed for the production of cell wall ingrowths in syncytia and that their lack leads to a reduced host suitability for H. schachtii resulting in smaller syncytia, lower number of developing nematodes, and smaller females.
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Affiliation(s)
- Shahid Siddique
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Miroslaw Sobczak
- Department of Botany, Warsaw University of Life Sciences (SGGW), Warsaw, Poland
| | - Raimund Tenhaken
- Division of Plant Physiology, University of Salzburg, Salzburg, Austria
| | - Florian M. W. Grundler
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Holger Bohlmann
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
- * E-mail:
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Lima-Silva V, Rosado A, Amorim-Silva V, Muñoz-Mérida A, Pons C, Bombarely A, Trelles O, Fernández-Muñoz R, Granell A, Valpuesta V, Botella MÁ. Genetic and genome-wide transcriptomic analyses identify co-regulation of oxidative response and hormone transcript abundance with vitamin C content in tomato fruit. BMC Genomics 2012; 13:187. [PMID: 22583865 PMCID: PMC3462723 DOI: 10.1186/1471-2164-13-187] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 04/25/2012] [Indexed: 12/02/2022] Open
Abstract
Background L-ascorbic acid (AsA; vitamin C) is essential for all living plants where it functions as the main hydrosoluble antioxidant. It has diverse roles in the regulation of plant cell growth and expansion, photosynthesis, and hormone-regulated processes. AsA is also an essential component of the human diet, being tomato fruit one of the main sources of this vitamin. To identify genes responsible for AsA content in tomato fruit, transcriptomic studies followed by clustering analysis were applied to two groups of fruits with contrasting AsA content. These fruits were identified after AsA profiling of an F8 Recombinant Inbred Line (RIL) population generated from a cross between the domesticated species Solanum lycopersicum and the wild relative Solanum pimpinellifollium. Results We found large variability in AsA content within the RIL population with individual RILs with up to 4-fold difference in AsA content. Transcriptomic analysis identified genes whose expression correlated either positively (PVC genes) or negatively (NVC genes) with the AsA content of the fruits. Cluster analysis using SOTA allowed the identification of subsets of co-regulated genes mainly involved in hormones signaling, such as ethylene, ABA, gibberellin and auxin, rather than any of the known AsA biosynthetic genes. Data mining of the corresponding PVC and NVC orthologs in Arabidopis databases identified flagellin and other ROS-producing processes as cues resulting in differential regulation of a high percentage of the genes from both groups of co-regulated genes; more specifically, 26.6% of the orthologous PVC genes, and 15.5% of the orthologous NVC genes were induced and repressed, respectively, under flagellin22 treatment in Arabidopsis thaliana. Conclusion Results here reported indicate that the content of AsA in red tomato fruit from our selected RILs are not correlated with the expression of genes involved in its biosynthesis. On the contrary, the data presented here supports that AsA content in tomato fruit co-regulates with genes involved in hormone signaling and they are dependent on the oxidative status of the fruit.
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Affiliation(s)
- Viviana Lima-Silva
- Departamento Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea, Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Universidad de Málaga, 29071, Málaga, Spain
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Alford SR, Rangarajan P, Williams P, Gillaspy GE. myo-Inositol Oxygenase is Required for Responses to Low Energy Conditions in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2012; 3:69. [PMID: 22639659 PMCID: PMC3355591 DOI: 10.3389/fpls.2012.00069] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 03/22/2012] [Indexed: 05/03/2023]
Abstract
myo-Inositol is a precursor for cell wall components, is used as a backbone of myo-inositol trisphosphate (Ins(1,4,5)P(3)) and phosphatidylinositol phosphate signaling molecules, and is debated about whether it is also a precursor in an alternate ascorbic acid synthesis pathway. Plants control inositol homeostasis by regulation of key enzymes involved in myo-inositol synthesis and catabolism. Recent transcriptional profiling data indicate up-regulation of the myo-inositol oxygenase (MIOX) genes under conditions in which energy or nutrients are limited. To test whether the MIOX genes are required for responses to low energy, we first examined MIOX2 and MIOX4 gene expression regulation by energy/nutrient conditions. We found that both MIOX2 and MIOX4 expression are suppressed by exogenous glucose addition in the shoot, but not in the root. Both genes were abundantly expressed during low energy/nutrient conditions. Loss-of-function mutants in MIOX genes contain alterations in myo-inositol levels and growth changes in the root. Miox2 mutants can be complemented with a MIOX2:green fluorescent protein fusion. Further we show here that MIOX2 is a cytoplasmic protein, while MIOX4 is present mostly in the cytoplasm, but also occasionally in the nucleus. Together, these data suggest that MIOX catabolism in the shoot may influence root growth responses during low energy/nutrient conditions.
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Affiliation(s)
| | | | - Phoebe Williams
- Department of Biochemistry, Virginia TechBlacksburg, VA, USA
| | - Glenda E. Gillaspy
- Department of Biochemistry, Virginia TechBlacksburg, VA, USA
- *Correspondence: Glenda E. Gillaspy, Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA. e-mail:
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Munnik T, Nielsen E. Green light for polyphosphoinositide signals in plants. CURRENT OPINION IN PLANT BIOLOGY 2011; 14:489-97. [PMID: 21775194 DOI: 10.1016/j.pbi.2011.06.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 06/21/2011] [Accepted: 06/23/2011] [Indexed: 05/04/2023]
Abstract
Plant genomes lack homologues of the inositol 1,4,5-trisphosphate receptor and protein kinase C, which are important components of the canonical phospholipase C signalling system in animals. Instead, plants seem to utilize alternative downstream signalling molecules, that is, InsP(6) and phosphatidic acid. Inositol lipids may also function as second messengers themselves. By reversible phosphorylation of the inositol headgroup, five biologically active plant polyphosphoinositides can be detected. Protein targets interact with specific polyphosphoinositide isomers via selective lipid-binding domains, thereby altering their intracellular localization and/or enzymatic activity. Such lipid-binding domains have also been used to create GFP based-lipid biosensors to visualize PPIs dynamics in vivo. Here, we highlight some recent advances and ideas on PPIs' role in plant signalling.
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Affiliation(s)
- Teun Munnik
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands.
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Reboul R, Geserick C, Pabst M, Frey B, Wittmann D, Lütz-Meindl U, Léonard R, Tenhaken R. Down-regulation of UDP-glucuronic acid biosynthesis leads to swollen plant cell walls and severe developmental defects associated with changes in pectic polysaccharides. J Biol Chem 2011; 286:39982-92. [PMID: 21949134 DOI: 10.1074/jbc.m111.255695] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
UDP-glucose dehydrogenase (UGD) plays a key role in the nucleotide sugar biosynthetic pathway, as its product UDP-glucuronic acid is the common precursor for arabinose, xylose, galacturonic acid, and apiose residues found in the cell wall. In this study we characterize an Arabidopsis thaliana double mutant ugd2,3 that lacks two of the four UGD isoforms. This mutant was obtained from a cross of ugd2 and ugd3 single mutants, which do not show phenotypical differences compared with the WT. In contrast, ugd2,3 has a strong dwarfed phenotype and often develops seedlings with severe root defects suggesting that the UGD2 and UGD3 isoforms act in concert. Differences in its cell wall composition in comparison to the WT were determined using biochemical methods indicating a significant reduction in arabinose, xylose, apiose, and galacturonic acid residues. Xyloglucan is less substituted with xylose, and pectins have a reduced amount of arabinan side chains. In particular, the amount of the apiose containing side chains A and B of rhamnogalacturonan II is strongly reduced, resulting in a swollen cell wall. The alternative pathway to UDP-glucuronic acid with the key enzyme myo-inositol oxygenase is not up-regulated in ugd2,3. The pathway also does not complement the ugd2,3 mutation, likely because the supply of myo-inositol is limited. Taken together, the presented data underline the importance of UDP GlcA for plant primary cell wall formation.
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Affiliation(s)
- Rebecca Reboul
- Department of Cell Biology, Molecular Cell Physiology, University of Salzburg, 5020 Salzburg, Austria
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