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Da Ros L, Bollina V, Soolanayakanahally R, Pahari S, Elferjani R, Kulkarni M, Vaid N, Risseuw E, Cram D, Pasha A, Esteban E, Konkin D, Provart N, Nambara E, Kagale S. Multi-omics atlas of combinatorial abiotic stress responses in wheat. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:1118-1135. [PMID: 37248640 DOI: 10.1111/tpj.16332] [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: 05/01/2022] [Revised: 05/10/2023] [Accepted: 05/26/2023] [Indexed: 05/31/2023]
Abstract
Field-grown crops rarely experience growth conditions in which yield can be maximized. Environmental stresses occur in combination, with advancements in crop tolerance further complicated by its polygenic nature. Strategic targeting of causal genes is required to meet future crop production needs. Here, we employed a systems biology approach in wheat (Triticum aestivum L.) to investigate physio-metabolic adjustments and transcriptome reprogramming involved in acclimations to heat, drought, salinity and all combinations therein. A significant shift in magnitude and complexity of plant response was evident across stress scenarios based on the agronomic losses, increased proline concentrations and 8.7-fold increase in unique differentially expressed transcripts (DETs) observed under the triple stress condition. Transcriptome data from all stress treatments were assembled into an online, open access eFP browser for visualizing gene expression during abiotic stress. Weighted gene co-expression network analysis revealed 152 hub genes of which 32% contained the ethylene-responsive element binding factor-associated amphiphilic repression (EAR) transcriptional repression motif. Cross-referencing against the 31 DETs common to all stress treatments isolated TaWRKY33 as a leading candidate for greater plant tolerance to combinatorial stresses. Integration of our findings with available literature on gene functional characterization allowed us to further suggest flexible gene combinations for future adaptive gene stacking in wheat. Our approach demonstrates the strength of robust multi-omics-based data resources for gene discovery in complex environmental conditions. Accessibility of such datasets will promote cross-validation of candidate genes across studies and aid in accelerating causal gene validation for crop resiliency.
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Affiliation(s)
- Letitia Da Ros
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
- Summerland Research and Development Centre, Agriculture and Agri-Food Canada, Summerland, British Columbia, Canada
| | - Venkatesh Bollina
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
| | - Raju Soolanayakanahally
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan, Canada
| | - Shankar Pahari
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan, Canada
| | - Raed Elferjani
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan, Canada
| | - Manoj Kulkarni
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
| | - Neha Vaid
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Eddy Risseuw
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
| | - Dustin Cram
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
| | - Asher Pasha
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Eddi Esteban
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - David Konkin
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
| | - Nicholas Provart
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Eiji Nambara
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Sateesh Kagale
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada
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Ibrahim MM, Mounier MM, Bekheet SA. Targeting apoptotic anticancer response with natural glucosinolates from cell suspension culture of Lepidium sativum. J Genet Eng Biotechnol 2023; 21:53. [PMID: 37127764 PMCID: PMC10151292 DOI: 10.1186/s43141-023-00511-y] [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: 05/21/2022] [Accepted: 04/20/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND Finding natural products with anticancer activity is an effective strategy to fight this disease. In this respect, Lepidium sativum or garden cress (family Brassicaceae) has been widely used worldwide for its wide therapeutic application, including anticancer and chemoprotective agents. Plant tissue culture techniques hold great promise for natural product enhancement without any climatic boundaries. In this study, glucosinolates and petroleum ether fractions were isolated from in vitro cell cultures and used against different carcinoma cell lines to investigate their anticancer potential. METHODS In this study, callus cultures from leaf and root explants were initiated, cell suspension cultures were established, and cell growth and viability profiles were characterized. Different amino acids were added as precursors to the cell suspension cultures to enhance glucosinolates accumulation. Gas chromatography-mass spectrometric analysis (GC-MS) of glucosinolates and petroleum ether fractions was performed, and all fractions were tested against different carcinoma cell lines. RESULTS The findings clarified that the maximum callus initiation percentage was obtained in the medium containing 1.0 mg/l 2,4-dichlorophenoxy acetic acid (2,4-D) + 1.0 mg/l kinetin (Kin) (C1). The viable cell number of cell suspension cultures from leaves and roots increased until it reached the maximum values on day 15. Adding tyrosine and methionine to the cell suspension cultures was the most influential and recorded high glucosinolate percentages. 1H-Cyclopenta (b) pyridine-3-carbonitrile-4,5,6,7-tetrahydro-2-methylthio-4-spirocyclohexane was the main glucosinolate compound found in tyrosine-treated leaf suspension (GLT). Fifteen compounds were detected in the petroleum ether fraction in both cell suspensions initiated from the leaf and root (OL and OR). The major compounds were benzene-1,3,5-trimethyl (12.99%) in root cell suspension (OR), and benzene-2-ethyl-1,4-dimethyl (10.66%) in leaf cell suspension (OL). All glucosinolate extracts demonstrated significant anticancer activity against the prostate (PC3), lung (A-549), colorectal (caco2), and liver (HepG2) cell lines. Glucosinolates extracted from leaf cell suspension (GL) were the most active on the hepatocellular carcinoma cell line (HepG2) among all remaining glucosinolate extracts. Treated hepatocellular carcinoma with an IC50 of GL extract (47.5 ug/ml) upregulates pro-apoptotic BAX and downregulates anti-apoptotic BCL2, which disrupts the BAX/BCL2 ratio, leading to activation of caspase 3 inside treated HepG2 cells. CONCLUSIONS The anticancer action of the GL extract was validated by the cell cycle study of its glucosinolates, which successfully promoted apoptosis and reduced hepatocellular growth by causing S-phase arrest.
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Affiliation(s)
- Mona M Ibrahim
- Department of Plant Biotechnology, Biotechnology Research Institute, National Research Centre, Cairo, 12622, Egypt.
| | - Marwa M Mounier
- Department of Pharmacognosy, Pharmaceutical and Drug Industries Research Institute, National Research Centre, Cairo, 12622, Egypt
| | - Shawky A Bekheet
- Department of Plant Biotechnology, Biotechnology Research Institute, National Research Centre, Cairo, 12622, Egypt
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Yang T, Wu X, Wang W, Wu Y. Regulation of seed storage protein synthesis in monocot and dicot plants: A comparative review. MOLECULAR PLANT 2023; 16:145-167. [PMID: 36495013 DOI: 10.1016/j.molp.2022.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/27/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Seeds are a major source of nutrients for humans and animal livestock worldwide. With improved living standards, high nutritional quality has become one of the main targets for breeding. Storage protein content in seeds, which is highly variable depending on plant species, serves as a pivotal criterion of seed nutritional quality. In the last few decades, our understanding of the molecular genetics and regulatory mechanisms of storage protein synthesis has greatly advanced. Here, we systematically and comprehensively summarize breakthroughs on the conservation and divergence of storage protein synthesis in dicot and monocot plants. With regard to storage protein accumulation, we discuss evolutionary origins, developmental processes, characteristics of main storage protein fractions, regulatory networks, and genetic modifications. In addition, we discuss potential breeding strategies to improve storage protein accumulation and provide perspectives on some key unanswered problems that need to be addressed.
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Affiliation(s)
- Tao Yang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Xingguo Wu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200233, China
| | - Wenqin Wang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200233, China
| | - Yongrui Wu
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
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Bhinder G, Sharma S, Kaur H, Akhatar J, Mittal M, Sandhu S. Genomic Regions Associated With Seed Meal Quality Traits in Brassica napus Germplasm. FRONTIERS IN PLANT SCIENCE 2022; 13:882766. [PMID: 35909769 PMCID: PMC9333065 DOI: 10.3389/fpls.2022.882766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 04/20/2022] [Indexed: 06/15/2023]
Abstract
The defatted Brassica napus (rapeseed) meal can be high-protein feed for livestock as the protein value of rapeseed meal is higher than that of the majority of other vegetable proteins. Extensive work has already been carried out on developing canola rapeseed where the focus was on reducing erucic acid and glucosinolate content, with less consideration to other antinutritional factors such as tannin, phytate, sinapine, crude fiber, etc. The presence of these antinutrients limits the use and marketing of rapeseed meals and a significant amount of it goes unused and ends up as waste. We investigated the genetic architecture of crude protein, methionine, tryptophan, total phenols, β-carotene, glucosinolates (GLSs), phytate, tannins, sinapine, and crude fiber content of defatted seed meal samples by conducting a genome-wide association study (GWAS), using a diversity panel comprising 96 B. napus genotypes. Genotyping by sequencing was used to identify 77,889 SNPs, spread over 19 chromosomes. Genetic diversity and phenotypic variations were generally high for the studied traits. A total of eleven genotypes were identified which showed high-quality protein, high antioxidants, and lower amount of antinutrients. A significant negative correlation between protein and limiting amino acids and a significant positive correlation between GLS and phytic acid were observed. General and mixed linear models were used to estimate the association between the SNP markers and the seed quality traits and quantile-quantile (QQ) plots were generated to allow the best-fit algorithm. Annotation of genomic regions around associated SNPs helped to predict various trait-related candidates such as ASP2 and EMB1027 (amino acid biosynthesis); HEMA2, GLU1, and PGM (tryptophan biosynthesis); MS3, CYSD1, and MTO1 (methionine biosynthesis); LYC (β-carotene biosynthesis); HDR and ISPF (MEP pathway); COS1 (riboflavin synthesis); UGT (phenolics biosynthesis); NAC073 (cellulose and hemicellulose biosynthesis); CYT1 (cellulose biosynthesis); BGLU45 and BGLU46 (lignin biosynthesis); SOT12 and UGT88A1 (flavonoid pathway); and CYP79A2, DIN2, and GSTT2 (GLS metabolism), etc. The functional validation of these candidate genes could confirm key seed meal quality genes for germplasm enhancement programs directed at improving protein quality and reducing the antinutritional components in B. napus.
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Affiliation(s)
| | - Sanjula Sharma
- Oilseeds Section, Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, India
| | | | - Javed Akhatar
- Oilseeds Section, Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, India
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Singh A, Sharma A, Singh N, Nandi AK. MTO1-RESPONDING DOWN 1 (MRD1) is a transcriptional target of OZF1 for promoting salicylic acid-mediated defense in Arabidopsis. PLANT CELL REPORTS 2022; 41:1319-1328. [PMID: 35325291 DOI: 10.1007/s00299-022-02861-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
OZF1 promotes the transcription of MRD1, which is essential for SA-mediated defense against virulent and avirulent bacterial pathogens in Arabidopsis. Salicylic acid (SA) is critical for defense against biotrophic pathogens. A trans-activator protein NPR1 plays significant roles in SA-signaling. However, evidences suggest the existence of NPR1-independent pathways for SA signaling in plants. Previously, we reported Arabidopsis OXIDATION-RELATED ZN-FINGER PROTEIN1 (OZF1) as a positive regulator of NPR1-independent SA-signaling. However, the mechanism or components of OZF1-mediated SA signaling was not known. Through the analysis of differentially expressing genes, we report the identification of MTO1-RESPONDING DOWN 1 (MRD1) as a transcriptional target of OZF1. Expressions of MRD1 and its overlapping gene in Arabidopsis genome, HEI10 increase upon pathogen inoculation in an OZF1-dependent manner. Their mutants are susceptible to both virulent and avirulent bacterial pathogens and show compromised SA-mediated immunity. Overexpression of MRD1 but not the HEI10 rescues the loss-of-resistance phenotype of the ozf1 mutant. OZF1 physically associates at the MRD1 promoter area upon pathogen inoculation. Results altogether support that MRD1 is a transcriptional target of OZF1 for promoting SA-mediated defense in Arabidopsis.
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Affiliation(s)
- Anupriya Singh
- 415, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Akash Sharma
- 415, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Nidhi Singh
- 415, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Ashis Kumar Nandi
- 415, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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Drought-Induced Regulatory Cascades and Their Effects on the Nutritional Quality of Developing Potato Tubers. Genes (Basel) 2020; 11:genes11080864. [PMID: 32751417 PMCID: PMC7465940 DOI: 10.3390/genes11080864] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 01/22/2023] Open
Abstract
Competition for scarce water resources and the continued effects of global warming exacerbate current constraints on potato crop production. While plants’ response to drought in above-ground tissues has been well documented, the regulatory cascades and subsequent nutritive changes in developing tubers have been largely unexplored. Using the commercial Canadian cultivar “Vigor”, plants were subjected to a gradual drought treatment under high tunnels causing a 4 °C increase in the canopy temperature. Tubers were sampled for RNAseq and metabolite analysis. Approximately 2600 genes and 3898 transcripts were differentially expressed by at least 4-fold in drought-stressed potato tubers, with 75% and 69% being down-regulated, respectively. A further 229 small RNAs were implicated in gene regulation during drought. Expression of several small RNA clusters negatively correlated with expression of their six target patatin genes, suggesting involvement in the regulation of storage proteins during drought. The comparison of protein homologues between Solanum tuberosum L. and Arabidopsis thaliana L. indicated that down-regulated genes were associated with phenylpropanoid and carotenoid biosynthesis. As is indicative of reduced flow through the phenylpropanoid pathway, phenylalanine accumulated in drought-stressed tubers. This suggests that there may be nutritive implications to drought stress occurring during the potato tuber bulking phase in sensitive cultivars.
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Amir R, Cohen H, Hacham Y. Revisiting the attempts to fortify methionine content in plant seeds. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:4105-4114. [PMID: 30911752 DOI: 10.1093/jxb/erz134] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
The sulfur-containing amino acid methionine belongs to the group of essential amino acids, meaning that humans and animals must consume it in their diets. However, plant seeds have low levels of methionine, limiting their nutritional potential. For this reason, efforts have been made over the years to increase methionine levels in seeds. Here, we summarize these efforts and focus particularly on those utilizing diverse genetic and molecular tools. Four main approaches are described: (i) expression of methionine-rich storage proteins in a seed-specific manner to incorporate more soluble methionine into the protein fraction; (ii) reduction of methionine-poor storage proteins inside the seeds to reinforce the accumulation of methionine-rich proteins; (iii) silencing methionine catabolic enzymes; and (iv) up-regulation of key biosynthetic enzymes participating in methionine synthesis. We focus on the biosynthetic genes that operate de novo in seeds and that belong to the sulfur assimilation and aspartate family pathways, as well as genes from the methionine-specific pathway. We also include those enzymes that operate in non-seed tissues that contribute to the accumulation of methionine in seeds, such as S-methylmethionine enzymes. Finally, we discuss the biotechnological potential of these manipulations to increase methionine content in plant seeds and their effect on seed germination.
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Affiliation(s)
- Rachel Amir
- Laboratory of Plant Science, Migal - Galilee Technology Center, Kiryat Shmona, Israel
- Tel-Hai College, Upper Galilee, Israel
| | - Hagai Cohen
- Department of Plant & Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Yael Hacham
- Laboratory of Plant Science, Migal - Galilee Technology Center, Kiryat Shmona, Israel
- Tel-Hai College, Upper Galilee, Israel
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8
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Reyes-Hernández BJ, Shishkova S, Amir R, Quintana-Armas AX, Napsucialy-Mendivil S, Cervantes-Gamez RG, Torres-Martínez HH, Montiel J, Wood CD, Dubrovsky JG. Root stem cell niche maintenance and apical meristem activity critically depend on THREONINE SYNTHASE1. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3835-3849. [PMID: 30972413 DOI: 10.1093/jxb/erz165] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 03/22/2019] [Indexed: 05/23/2023]
Abstract
Indeterminate root growth depends on the stem cell niche (SCN) and root apical meristem (RAM) maintenance whose regulation permits plasticity in root system formation. Using a forward genetics approach, we isolated the moots koom1 ('short root' in Mayan) mutant that shows complete primary RAM exhaustion and abolished SCN activity. We identified that this phenotype is caused by a point mutation in the METHIONINE OVERACCUMULATOR2 (MTO2) gene that encodes THREONINE SYNTHASE1 and renamed the mutant as mto2-2. The amino acid profile showed drastic changes, most notorious of which was accumulation of methionine. In non-allelic mto1-1 (Arabidopsis thaliana cystathionine gamma-synthetase1) and mto3-1 (S-adenosylmethionine synthetase) mutants, both with an increased methionine level, the RAM size was similar to that of the wild type, suggesting that methionine overaccumulation itself did not cause RAM exhaustion in mto2 mutants. When mto2-2 RAM is not yet completely exhausted, exogenous threonine induced de novo SCN establishment and root growth recovery. The threonine-dependent RAM re-establishment in mto2-2 suggests that threonine is a limiting factor for RAM maintenance. In the root, MTO2 was predominantly expressed in the RAM. The essential role of threonine in mouse embryonic stem cells and in RAM maintenance suggests that common regulatory mechanisms may operate in plant and animal SCN maintenance.
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Affiliation(s)
- Blanca Jazmín Reyes-Hernández
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Svetlana Shishkova
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Rachel Amir
- Laboratory of Plant Science, MIGAL-Galilee Research Institute, Kiryat Shmona, Israel
- Tel-Hai College, Upper Galilee, Israel
| | - Aranza Xhaly Quintana-Armas
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Selene Napsucialy-Mendivil
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Rocio Guadalupe Cervantes-Gamez
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Héctor Hugo Torres-Martínez
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Jesús Montiel
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Christopher D Wood
- Laboratorio Nacional de Microscopía Avanzada, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Joseph G Dubrovsky
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
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Matityahu I, Godo I, Hacham Y, Amir R. The level of threonine in tobacco seeds is limited by substrate availability, while the level of methionine is limited also by the activity of cystathionine γ-synthase. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 283:195-201. [PMID: 31128689 DOI: 10.1016/j.plantsci.2019.02.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/25/2019] [Accepted: 02/28/2019] [Indexed: 06/09/2023]
Abstract
Methionine and threonine are two essential amino acids whose low levels limit the nutritional quality of seeds. The current objective was to define factors that regulate and might increase their levels in seeds. Feeding experiments carried out on receptacles of developing tobacco (Nicotiana tabacum) capsules showed that 1 mM of S-methylmethionine increased the level of methionine to contents similar to 2.5 mM of homoserine, an intermediate metabolite of the aspartate family of amino acids. The latter also increased the level of threonine. Based on these findings, we generated tobacco seeds that expressed a combination of bacterial feedback-insensitive aspartate kinase (bAK), which was previously reported to have a high level of threonine/methionine, and feedback-insensitive cystathionine γ-synthase (CGS), the regulatory enzyme of the methionine biosynthesis pathway. Plants expressing this latter gene previously showed having higher levels of methionine. The results of total amino acids analysis showed that the level of threonine was highest in the bAK line, which has moderate levels of methionine and lysine, while the highest level of methionine was found in seeds expressing both heterologous genes. The results suggest that the level of threonine in tobacco seeds is limited by the substrate, while that of methionine is limited also by the activity of CGS.
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Affiliation(s)
- I Matityahu
- Laboratory of Plant Science, Migal - Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
| | - I Godo
- Laboratory of Plant Science, Migal - Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
| | - Y Hacham
- Laboratory of Plant Science, Migal - Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel; Tel-Hai College, Upper Galilee 11016, Israel
| | - R Amir
- Laboratory of Plant Science, Migal - Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel; Tel-Hai College, Upper Galilee 11016, Israel.
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Petersen A, Wang C, Crocoll C, Halkier BA. Biotechnological approaches in glucosinolate production. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2018; 60:1231-1248. [PMID: 30080309 PMCID: PMC6585788 DOI: 10.1111/jipb.12705] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/31/2018] [Indexed: 05/21/2023]
Abstract
Glucosinolates (GLSs) are sulfur-rich, amino acid-derived defense compounds characteristic of the Brassicales order. In the past, GLSs were mostly known as anti-nutritional factors in fodder, biopesticides in agriculture, and flavors in condiments such as mustard. However, in recent times, GLSs have received increased attention as promoters of human health. This has spurred intensive research towards generating rich sources of health-promoting GLSs. We provide a comprehensive overview of the biotechnological approaches applied to reach this goal. This includes optimization of GLS production and composition in native, GLS-producing plants, including hairy root and cell cultures thereof, as well as synthetic biology approaches in heterologous hosts, such as tobacco and the microbial organisms Escherichia coli and Saccharomyces cerevisiae. The progress using these different approaches is discussed.
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Affiliation(s)
- Annette Petersen
- DynaMo CenterCopenhagen Plant Science CentreDepartment of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark
| | - Cuiwei Wang
- DynaMo CenterCopenhagen Plant Science CentreDepartment of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark
| | - Christoph Crocoll
- DynaMo CenterCopenhagen Plant Science CentreDepartment of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark
| | - Barbara Ann Halkier
- DynaMo CenterCopenhagen Plant Science CentreDepartment of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark
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Whitcomb SJ, Nguyen HC, Brückner F, Hesse H, Hoefgen R. CYSTATHIONINE GAMMA-SYNTHASE activity in rice is developmentally regulated and strongly correlated with sulfate. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 270:234-244. [PMID: 29576077 DOI: 10.1016/j.plantsci.2018.02.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/14/2018] [Accepted: 02/16/2018] [Indexed: 06/08/2023]
Abstract
An important goal of rice cultivar development is improvement of protein quality, especially with respect to essential amino acids such as methionine. With the goal of increasing seed methionine content, we generated Oryza sativa ssp. japonica cv. Taipei 309 transgenic lines expressing a feedback-desensitized CYSTATHIONINE GAMMA-SYNTHASE from Arabidopsis thaliana (AtD-CGS) under the control of the maize ubiquitin promoter. Despite persistently elevated cystathionine gamma-synthase (CGS) activity in the AtD-CGS transgenic lines relative to untransformed Taipei, sulfate was the only sulfur-containing compound found to be elevated throughout vegetative development. Accumulation of methionine and other sulfur-containing metabolites was limited to the leaves of young plants. Sulfate concentration was found to strongly and positively correlate with CGS activity across vegetative development, irrespective of whether the activity was provided by the endogenous rice CGS or by a combination of endogenous and AtD-CGS. Conversely, the concentrations of glutathione, valine, and leucine were clearly negatively correlated with CGS activity in the same tissues. We also observed a strong decrease in CGS activity in both untransformed Taipei and the AtD-CGS transgenic lines as the plants approached heading stage. The mechanism for this downregulation is currently unknown and of potential importance for efforts to increase methionine content in rice.
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Affiliation(s)
- Sarah J Whitcomb
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
| | - Huu Cuong Nguyen
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany; University of Potsdam, Institute for Biochemistry and Biology, AG Genetics, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
| | - Franziska Brückner
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
| | - Holger Hesse
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
| | - Rainer Hoefgen
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
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12
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Cohen H, Salmon A, Tietel Z, Hacham Y, Amir R. The relative contribution of genes operating in the S-methylmethionine cycle to methionine metabolism in Arabidopsis seeds. PLANT CELL REPORTS 2017; 36:731-743. [PMID: 28289884 DOI: 10.1007/s00299-017-2124-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 02/22/2017] [Indexed: 05/02/2023]
Abstract
Enzymes operating in the S -methylmethionine cycle make a differential contribution to methionine synthesis in seeds. In addition, mutual effects exist between the S -methylmethionine cycle and the aspartate family pathway in seeds. Methionine, a sulfur-containing amino acid, is a key metabolite in plant cells. The previous lines of evidence proposed that the S-methylmethionine (SMM) cycle contributes to methionine synthesis in seeds where methionine that is produced in non-seed tissues is converted to SMM and then transported via the phloem into the seeds. However, the relative regulatory roles of the S-methyltransferases operating within this cycle in seeds are yet to be fully understood. In the current study, we generated transgenic Arabidopsis seeds with altered expression of three HOMOCYSTEINE S-METHYLTRANSFERASEs (HMTs) and METHIONINE S-METHYLTRANSFERASE (MMT), and profiled them for transcript and metabolic changes. The results revealed that AtHMT1 and AtHMT3, but not AtHMT2 and AtMMT, are the predominant enzymes operating in seeds as altered expression of these two genes affected the levels of methionine and SMM in transgenic seeds. Their manipulations resulted in adapted expression level of genes participating in methionine synthesis through the SMM and aspartate family pathways. Taken together, our findings provide new insights into the regulatory roles of the SMM cycle and the mutual effects existing between the two methionine biosynthesis pathways, highlighting the complexity of the metabolism of methionine and SMM in seeds.
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Affiliation(s)
- Hagai Cohen
- Laboratory of Plant Science, Migal Galilee Technology Center, 12100, Kiryat Shmona, Israel
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Asaf Salmon
- Laboratory of Plant Science, Migal Galilee Technology Center, 12100, Kiryat Shmona, Israel
- Tel-Hai College, 11016, Upper Galilee, Israel
| | - Zipora Tietel
- Gilat Volcani Center, Agricultural Research Organization (ARO), Negev, Israel
| | - Yael Hacham
- Laboratory of Plant Science, Migal Galilee Technology Center, 12100, Kiryat Shmona, Israel
| | - Rachel Amir
- Laboratory of Plant Science, Migal Galilee Technology Center, 12100, Kiryat Shmona, Israel.
- Tel-Hai College, 11016, Upper Galilee, Israel.
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Chen Y, Zou T, McCormick S. S-Adenosylmethionine Synthetase 3 Is Important for Pollen Tube Growth. PLANT PHYSIOLOGY 2016; 172:244-53. [PMID: 27482079 PMCID: PMC5074607 DOI: 10.1104/pp.16.00774] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/30/2016] [Indexed: 05/03/2023]
Abstract
S-Adenosylmethionine is widely used in a variety of biological reactions and participates in the methionine (Met) metabolic pathway. In Arabidopsis (Arabidopsis thaliana), one of the four S-adenosylmethionine synthetase genes, METHIONINE ADENOSYLTRANSFERASE3 (MAT3), is highly expressed in pollen. Here, we show that mat3 mutants have impaired pollen tube growth and reduced seed set. Metabolomics analyses confirmed that mat3 pollen and pollen tubes overaccumulate Met and that mat3 pollen has several metabolite profiles, such as those of polyamine biosynthesis, which are different from those of the wild type. Additionally, we show that disruption of Met metabolism in mat3 pollen affected transfer RNA and histone methylation levels. Thus, our results suggest a connection between metabolism and epigenetics.
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Affiliation(s)
- Yuan Chen
- Plant Gene Expression Center, United States Department of Agriculture-Agricultural Research Service, and Department of Plant and Microbial Biology, University of California Berkeley, Albany, California 94710
| | - Ting Zou
- Plant Gene Expression Center, United States Department of Agriculture-Agricultural Research Service, and Department of Plant and Microbial Biology, University of California Berkeley, Albany, California 94710
| | - Sheila McCormick
- Plant Gene Expression Center, United States Department of Agriculture-Agricultural Research Service, and Department of Plant and Microbial Biology, University of California Berkeley, Albany, California 94710
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14
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Optimization of a gas chromatography–mass spectrometry method with methyl chloroformate derivatization for quantification of amino acids in plant tissue. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1017-1018:241-249. [DOI: 10.1016/j.jchromb.2016.02.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/16/2016] [Accepted: 02/14/2016] [Indexed: 11/17/2022]
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15
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Cohen H, Pajak A, Pandurangan S, Amir R, Marsolais F. Higher endogenous methionine in transgenic Arabidopsis seeds affects the composition of storage proteins and lipids. Amino Acids 2016; 48:1413-22. [DOI: 10.1007/s00726-016-2193-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 02/02/2016] [Indexed: 01/03/2023]
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16
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Mao D, Yu F, Li J, Van de Poel B, Tan D, Li J, Liu Y, Li X, Dong M, Chen L, Li D, Luan S. FERONIA receptor kinase interacts with S-adenosylmethionine synthetase and suppresses S-adenosylmethionine production and ethylene biosynthesis in Arabidopsis. PLANT, CELL & ENVIRONMENT 2015; 38:2566-74. [PMID: 25988356 DOI: 10.1111/pce.12570] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 05/03/2015] [Accepted: 05/07/2015] [Indexed: 05/04/2023]
Abstract
Environmental inputs such as stress can modulate plant cell metabolism, but the detailed mechanism remains unclear. We report here that FERONIA (FER), a plasma membrane receptor-like kinase, may negatively regulate the S-adenosylmethionine (SAM) synthesis by interacting with two S-adenosylmethionine synthases (SAM1 and SAM2). SAM participates in ethylene, nicotianamine and polyamine biosynthetic pathways and provides the methyl group for protein and DNA methylation reactions. The Arabidopsis fer mutants contained a higher level of SAM and ethylene in plant tissues and displayed a dwarf phenotype. Such phenotype in the fer mutants was mimicked by over-expressing the S-adenosylmethionine synthetase in transgenic plants, whereas sam1/2 double mutant showed an opposite phenotype. We propose that FER receptor kinase, in response to environmental stress and plant hormones such as auxin and BR, interacts with SAM synthases and down-regulates ethylene biosynthesis.
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Affiliation(s)
- Dandan Mao
- NJU-NJFU Joint Institute for Plant Molecular Biology, School of Life Sciences, Nanjing University, Nanjing, 210093, China
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Feng Yu
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, 410082, China
| | - Jian Li
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Bram Van de Poel
- Division of Mechatronics, Biostatistics and Sensors (MeBioS), Department of Biosystems (BIOSYST), KU Leuven, Leuven, 3001, Belgium
| | - Dan Tan
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Jianglin Li
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Yanqionq Liu
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Xiushang Li
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, 410082, China
| | - Mengqiu Dong
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Liangbi Chen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Dongping Li
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Sheng Luan
- NJU-NJFU Joint Institute for Plant Molecular Biology, School of Life Sciences, Nanjing University, Nanjing, 210093, China
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
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Frank A, Cohen H, Hoffman D, Amir R. Methionine and S-methylmethionine exhibit temporal and spatial accumulation patterns during the Arabidopsis life cycle. Amino Acids 2014; 47:497-510. [PMID: 25488426 DOI: 10.1007/s00726-014-1881-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 11/18/2014] [Indexed: 11/26/2022]
Abstract
Methionine is a nutritionally essential sulfur-containing amino acid found at low levels in plant tissues. Yet, the factors that regulate its synthesis and accumulation in seeds are not fully known. Recent genetic studies demonstrate that Arabidopsis seeds are able to synthesize methionine de novo through the aspartate family pathway similarly to vegetative tissues; however, additional biochemical studies suggest that the S-methylmethionine (SMM) cycle also plays a major role in methionine synthesis in seeds. To better understand the contribution of these two pathways to methionine synthesis, we have sampled various vegetative and reproductive tissues during the Arabidopsis life cycle and determined the contents of soluble and protein-incorporated methionine, SMM, as well as the expression levels of the key genes involved in these two pathways. Our results strengthen the hypothesis that SMM that is produced in the rosette leaves from methionine contributes to methionine accumulation in seeds. However, the SMM cycle may have additional functions in plant tissues since its key genes were expressed in all of the examined tissues, although at different rates. The accumulation patterns of soluble and protein-incorporated methionine during the Arabidopsis life cycle were found to be similar to most of the other amino acids, especially to those belonging to the branched-chain and aromatic amino acids that are produced in chloroplasts together with methionine. This indicates that similar factors regulate the levels of amino acids during development.
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Affiliation(s)
- Alon Frank
- Laboratory of Plant Science, Migal, Galilee Research Institute Ltd., P.O.B. 831, 11016, Kiryat Shmona, Israel
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18
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Villeneuve S, Power KA, Guévremont E, Mondor M, Tsao R, Wanasundara JP, Zarepoor L, Mercier S. Effect of a Short-Time Germination Process on the Nutrient Composition, Microbial Counts and Bread-Making Potential of Whole Flaxseed. J FOOD PROCESS PRES 2014. [DOI: 10.1111/jfpp.12385] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Sébastien Villeneuve
- Food Research and Development Centre; Agriculture and Agri-Food Canada; 3600 Casavant Blvd. West Saint-Hyacinthe Quebec J2S 8E3 Canada
- Institute of Nutrition and Functional Foods (INAF); Laval University; Quebec Quebec G1K 7P4 Canada
| | - Krista A. Power
- Guelph Food Research Centre; Agriculture and Agri-Food Canada; Guelph Ontario Canada
| | - Evelyne Guévremont
- Food Research and Development Centre; Agriculture and Agri-Food Canada; 3600 Casavant Blvd. West Saint-Hyacinthe Quebec J2S 8E3 Canada
| | - Martin Mondor
- Food Research and Development Centre; Agriculture and Agri-Food Canada; 3600 Casavant Blvd. West Saint-Hyacinthe Quebec J2S 8E3 Canada
- Institute of Nutrition and Functional Foods (INAF); Laval University; Quebec Quebec G1K 7P4 Canada
| | - Rong Tsao
- Guelph Food Research Centre; Agriculture and Agri-Food Canada; Guelph Ontario Canada
| | | | - Leila Zarepoor
- Guelph Food Research Centre; Agriculture and Agri-Food Canada; Guelph Ontario Canada
| | - Samuel Mercier
- Food Research and Development Centre; Agriculture and Agri-Food Canada; 3600 Casavant Blvd. West Saint-Hyacinthe Quebec J2S 8E3 Canada
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Larrainzar E, Molenaar JA, Wienkoop S, Gil-Quintana E, Alibert B, Limami AM, Arrese-Igor C, González EM. Drought stress provokes the down-regulation of methionine and ethylene biosynthesis pathways in Medicago truncatula roots and nodules. PLANT, CELL & ENVIRONMENT 2014; 37:2051-63. [PMID: 24471423 DOI: 10.1111/pce.12285] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/19/2014] [Indexed: 05/04/2023]
Abstract
Symbiotic nitrogen fixation is one of the first physiological processes inhibited in legume plants under water-deficit conditions. Despite the progress made in the last decades, the molecular mechanisms behind this regulation are not fully understood yet. Recent proteomic work carried out in the model legume Medicago truncatula provided the first indications of a possible involvement of nodule methionine (Met) biosynthesis and related pathways in response to water-deficit conditions. To better understand this involvement, the drought-induced changes in expression and content of enzymes involved in the biosynthesis of Met, S-adenosyl-L-methionine (SAM) and ethylene in M. truncatula root and nodules were analyzed using targeted approaches. Nitrogen-fixing plants were subjected to a progressive water deficit and a subsequent recovery period. Besides the physiological characterization of the plants, the content of total sulphur, sulphate and main S-containing metabolites was measured. Results presented here show that S availability is not a limiting factor in the drought-induced decline of nitrogen fixation rates in M. truncatula plants and provide evidences for a down-regulation of the Met and ethylene biosynthesis pathways in roots and nodules in response to water-deficit conditions.
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Affiliation(s)
- Estíbaliz Larrainzar
- Dpto. Ciencias del Medio Natural, Universidad Pública de Navarra, 31006, Pamplona, Spain
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20
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Zhang Y, Schernthaner J, Labbé N, Hefford MA, Zhao J, Simmonds DH. Improved protein quality in transgenic soybean expressing a de novo synthetic protein, MB-16. Transgenic Res 2014; 23:455-67. [PMID: 24435987 DOI: 10.1007/s11248-013-9777-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 12/16/2013] [Indexed: 11/28/2022]
Abstract
To improve soybean [Glycine max (L.) Merrill] seed nutritional quality, a synthetic gene, MB-16 was introduced into the soybean genome to boost seed methionine content. MB-16, an 11 kDa de novo protein enriched in the essential amino acids (EAAs) methionine, threonine, lysine and leucine, was originally developed for expression in rumen bacteria. For efficient seed expression, constructs were designed using the soybean codon bias, with and without the KDEL ER retention sequence, and β-conglycinin or cruciferin seed specific protein storage promoters. Homozygous lines, with single locus integrations, were identified for several transgenic events. Transgene transmission and MB-16 protein expression were confirmed to the T5 and T7 generations, respectively. Quantitative RT-PCR analysis of developing seed showed that the transcript peaked in growing seed, 5-6 mm long, remained at this peak level to the full-sized green seed and then was significantly reduced in maturing yellow seed. Transformed events carrying constructs with the rumen bacteria codon preference showed the same transcription pattern as those with the soybean codon preference, but the transcript levels were lower at each developmental stage. MB-16 protein levels, as determined by immunoblots, were highest in full-sized green seed but the protein virtually disappeared in mature seed. However, amino acid analysis of mature seed, in the best transgenic line, showed a significant increase of 16.2 and 65.9 % in methionine and cysteine, respectively, as compared to the parent. This indicates that MB-16 elevated the sulfur amino acids, improved the EAA seed profile and confirms that a de novo synthetic gene can enhance the nutritional quality of soybean.
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Affiliation(s)
- Yunfang Zhang
- Eastern Cereals and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, ON, K1A0C6, Canada
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21
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Mohayeji M, Capriotti AL, Cavaliere C, Piovesana S, Samperi R, Stampachiacchiere S, Toorchi M, Lagana A. Heterosis profile of sunflower leaves: A label free proteomics approach. J Proteomics 2014; 99:101-10. [DOI: 10.1016/j.jprot.2014.01.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/21/2014] [Accepted: 01/27/2014] [Indexed: 12/24/2022]
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22
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Chang YL, Hsieh CL, Huang YM, Chiou WL, Kuo YH, Tseng MH. Modified method for determination of sulfur metabolites in plant tissues by stable isotope dilution-based liquid chromatography-electrospray ionization-tandem mass spectrometry. Anal Biochem 2013; 442:24-33. [PMID: 23911527 DOI: 10.1016/j.ab.2013.07.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2012] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 12/25/2022]
Abstract
A wide variety of sulfur metabolites play important roles in plant functions. We have developed a precise and sensitive method for the simultaneous measurement of several sulfur metabolites based on liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and (34)S metabolic labeling of sulfur-containing metabolites in Arabidopsis thaliana seedlings. However, some sulfur metabolites were unstable during the extraction procedure. Our proposed method does not allow for the detection of the important sulfur metabolite homocysteine because of its instability during sample extraction. Stable isotope-labeled sulfur metabolites of A. thaliana shoot were extracted and utilized as internal standards for quantification of sulfur metabolites with LC-MS/MS using S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), methionine (Met), glutathione (GSH), and glutathione disulfide (GSSG) as example metabolites. These metabolites were detected using electrospray ionization in positive mode. Standard curves were linear (r(2)>0.99) over a range of concentrations (SAM 0.01-2.0μM, SAH 0.002-0.10μM, Met 0.05-4.0μM, GSH 0.17-20.0μM, GSSG 0.07-20.0μM), with limits of detection for SAM, SAH, Met, GSH, and GSSG of 0.83, 0.67, 10, 0.56, and 1.1nM, respectively; and the within-run and between-run coefficients of variation based on quality control samples were less than 8%.
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Affiliation(s)
- Ya-Lan Chang
- Department of Applied Physics and Chemistry, University of Taipei, Taipei 10048, Taiwan
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23
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Hanafy MS, Rahman SM, Nakamoto Y, Fujiwara T, Naito S, Wakasa K, Ishimoto M. Differential response of methionine metabolism in two grain legumes, soybean and azuki bean, expressing a mutated form of Arabidopsis cystathionine γ-synthase. JOURNAL OF PLANT PHYSIOLOGY 2013; 170:338-45. [PMID: 23286999 DOI: 10.1016/j.jplph.2012.10.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 10/19/2012] [Accepted: 10/19/2012] [Indexed: 05/03/2023]
Abstract
Methionine (Met) is a sulfur-containing amino acid that is essential in mammals and whose low abundance limits the nutritional value of grain legumes. Cystathionine γ-synthase (CGS) catalyzes the first committed step of Met biosynthesis, and the stability of its mRNA is autoregulated by the cytosolic concentration of S-adenosyl-l-methionine (SAM), a direct metabolite of Met. The mto1-1 mutant of Arabidopsis thaliana harbors a mutation in the AtCGS1 gene that renders the mRNA resistant to SAM-dependent degradation and therefore results in the accumulation of free Met to high levels in young leaves. To manipulate Met biosynthesis in soybean and azuki bean, we introduced the AtCGS1 mto1-1 gene into the two grain legumes under the control of a seed-specific glycinin gene promoter. Transgenic seeds of both species accumulated soluble Met to levels at least twice those apparent in control seeds. However, the increase in free Met did not result in an increase in total Met content of the transgenic seeds. In transgenic azuki bean seeds, the amount of cystathionine, the direct product of CGS, was markedly increased whereas the total content of Met was significantly decreased compared with control seeds. Similar changes were not detected in soybean. Our data suggest that the regulation of Met biosynthesis differs between soybean and azuki bean, and that the expression of AtCGS1 mto1-1 differentially affects the metabolic stability of sulfur amino acids and their metabolites in the two grain legumes.
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Affiliation(s)
- Moemen S Hanafy
- National Agricultural Research Center for Hokkaido Region, 1 Hitsujigaoka, Toyohira, Sapporo, Hokkaido 062-8555, Japan
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Bruhn D, Møller IM, Mikkelsen TN, Ambus P. Terrestrial plant methane production and emission. PHYSIOLOGIA PLANTARUM 2012; 144:201-209. [PMID: 22136562 DOI: 10.1111/j.1399-3054.2011.01551.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this minireview, we evaluate all experimental work published on the phenomenon of aerobic methane (CH(4) ) generation in terrestrial plants and plant. Clearly, despite much uncertainty and skepticism, we conclude that the phenomenon is true. Four stimulating factors have been observed to induce aerobic plant CH(4) production, i.e. cutting injuries, increasing temperature, ultraviolet radiation and reactive oxygen species. Further, we analyze rates of measured emission of aerobically produced CH(4) in pectin and in plant tissues from different studies and argue that pectin is very far from the sole contributing precursor. In consequence, scaling up of aerobic CH(4) emission needs to take into consideration other potential sources than pectin. Due to the large uncertainties related to effects of stimulating factors, genotypic responses and type of precursors, we conclude that current attempts for upscaling aerobic CH(4) into a global budget is inadequate. Thus it is too early to draw the line under the aerobic methane emission in plants. Future work is needed for establishing the relative contribution of several proven potential CH(4) precursors in plant material.
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Affiliation(s)
- Dan Bruhn
- Risø National Laboratory for Sustainable Energy, Technical university of Denmark, Biosystems Division, BIO-309, Frederiksborgvej 399, DK-4000 Roskilde, Denmark.
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Murota K, Hagiwara-Komoda Y, Komoda K, Onouchi H, Ishikawa M, Naito S. Arabidopsis cell-free extract, ACE, a new in vitro translation system derived from Arabidopsis callus cultures. PLANT & CELL PHYSIOLOGY 2011; 52:1443-53. [PMID: 21677046 DOI: 10.1093/pcp/pcr080] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The analysis of post-transcriptional regulatory mechanisms in plants has benefited greatly from the use of cell-free extract systems. Arabidopsis as a model system provides extensive genetic resources; however, to date a suitable cell-free translation system from Arabidopsis has not been available. In this study, we devised an Arabidopsis cell-free extract (ACE) to be used for in vitro translation studies. Protoplasts were prepared from callus cultures derived from Arabidopsis seedlings, and cell-free extracts were prepared after evacuolation of the protoplasts by Percoll gradient centrifugation. The new ACE system exhibits translation activity comparable with that of the wheat germ extract system. We demonstrated that ACE prepared from the 5'-3' exoribonuclease-deficient mutant of Arabidopsis, xrn4-5, exhibited increased stability of an uncapped mRNA as compared with that from wild-type Arabidopsis. We applied the ACE system to study post-transcriptional regulation of AtCGS1. AtCGS1 codes for cystathionine γ-synthase (CGS) that catalyzes the first committed step of methionine and S-adenosyl-l-methionine (AdoMet) biosynthesis in plants, and is feedback regulated by mRNA degradation coupled with translation elongation arrest. The ACE system was capable of reproducing translation elongation arrest and subsequent AtCGS1 mRNA degradation that are induced by AdoMet. The ACE system described here can be prepared in a month after seed sowing and will make it possible to study post-transcriptional regulation of plant genes while taking advantage of the genetics of Arabidopsis.
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Affiliation(s)
- Katsunori Murota
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589 Japan
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26
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Stuttmann J, Hubberten HM, Rietz S, Kaur J, Muskett P, Guerois R, Bednarek P, Hoefgen R, Parker JE. Perturbation of Arabidopsis amino acid metabolism causes incompatibility with the adapted biotrophic pathogen Hyaloperonospora arabidopsidis. THE PLANT CELL 2011; 23:2788-803. [PMID: 21784950 PMCID: PMC3226217 DOI: 10.1105/tpc.111.087684] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/27/2011] [Accepted: 07/07/2011] [Indexed: 05/18/2023]
Abstract
Reliance of biotrophic pathogens on living plant tissues to propagate implies strong interdependence between host metabolism and nutrient uptake by the pathogen. However, factors determining host suitability and establishment of infection are largely unknown. We describe a loss-of-inhibition allele of ASPARTATE KINASE2 and a loss-of-function allele of DIHYDRODIPICOLINATE SYNTHASE2 identified in a screen for Arabidopsis thaliana mutants with increased resistance to the obligate biotrophic oomycete Hyaloperonospora arabidopsidis (Hpa). Through different molecular mechanisms, these mutations perturb amino acid homeostasis leading to overaccumulation of the Asp-derived amino acids Met, Thr, and Ile. Although detrimental for the plant, the mutations do not cause defense activation, and both mutants retain full susceptibility to the adapted obligate biotrophic fungus Golovinomyces orontii (Go). Chemical treatments mimicking the mutants' metabolic state identified Thr as the amino acid suppressing Hpa but not Go colonization. We conclude that perturbations in amino acid homeostasis render the mutant plants unsuitable as an infection substrate for Hpa. This may be explained by deployment of the same amino acid biosynthetic pathways by oomycetes and plants. Our data show that the plant host metabolic state can, in specific ways, influence the ability of adapted biotrophic strains to cause disease.
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Affiliation(s)
- Johannes Stuttmann
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | | | - Steffen Rietz
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Jagreet Kaur
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Paul Muskett
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Raphael Guerois
- Commissariat á l’Energie Atomique, Institut de Biologie et Technologies de Saclay, Laboratoire de Biologie Structurale et Radiobiologie and Centre National de la Recherche Scientifique, Unités de Recherche Associées 2096, F-91191 Gif-sur-Yvette, France
| | - Paweł Bednarek
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Rainer Hoefgen
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Jane E. Parker
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
- Address correspondence to
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Bryant N, Lloyd J, Sweeney C, Myouga F, Meinke D. Identification of nuclear genes encoding chloroplast-localized proteins required for embryo development in Arabidopsis. PLANT PHYSIOLOGY 2011; 155:1678-89. [PMID: 21139083 PMCID: PMC3091104 DOI: 10.1104/pp.110.168120] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 11/29/2010] [Indexed: 05/18/2023]
Abstract
We describe here the diversity of chloroplast proteins required for embryo development in Arabidopsis (Arabidopsis thaliana). Interfering with certain chloroplast functions has long been known to result in embryo lethality. What has not been reported before is a comprehensive screen for embryo-defective (emb) mutants altered in chloroplast proteins. From a collection of transposon and T-DNA insertion lines at the RIKEN chloroplast function database (http://rarge.psc.riken.jp/chloroplast/) that initially appeared to lack homozygotes and segregate for defective seeds, we identified 23 additional examples of EMB genes that likely encode chloroplast-localized proteins. Fourteen gene identities were confirmed with allelism tests involving duplicate mutant alleles. We then queried journal publications and the SeedGenes database (www.seedgenes.org) to establish a comprehensive dataset of 381 nuclear genes encoding chloroplast proteins of Arabidopsis associated with embryo-defective (119 genes), plant pigment (121 genes), gametophyte (three genes), and alternate (138 genes) phenotypes. Loci were ranked based on the level of certainty that the gene responsible for the phenotype had been identified and the protein product localized to chloroplasts. Embryo development is frequently arrested when amino acid, vitamin, or nucleotide biosynthesis is disrupted but proceeds when photosynthesis is compromised and when levels of chlorophyll, carotenoids, or terpenoids are reduced. Chloroplast translation is also required for embryo development, with genes encoding chloroplast ribosomal and pentatricopeptide repeat proteins well represented among EMB datasets. The chloroplast accD locus, which is necessary for fatty acid biosynthesis, is essential in Arabidopsis but not in Brassica napus or maize (Zea mays), where duplicated nuclear genes compensate for its absence or loss of function.
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Onoue N, Yamashita Y, Nagao N, Goto DB, Onouchi H, Naito S. S-adenosyl-L-methionine induces compaction of nascent peptide chain inside the ribosomal exit tunnel upon translation arrest in the Arabidopsis CGS1 gene. J Biol Chem 2011; 286:14903-12. [PMID: 21335553 PMCID: PMC3083191 DOI: 10.1074/jbc.m110.211656] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression of the Arabidopsis CGS1 gene, encoding the first committed enzyme of methionine biosynthesis, is feedback-regulated in response to S-adenosyl-L-methionine (AdoMet) at the mRNA level. This regulation is first preceded by temporal arrest of CGS1 translation elongation at the Ser-94 codon. AdoMet is specifically required for this translation arrest, although the mechanism by which AdoMet acts with the CGS1 nascent peptide remained elusive. We report here that the nascent peptide of CGS1 is induced to form a compact conformation within the exit tunnel of the arrested ribosome in an AdoMet-dependent manner. Cysteine residues introduced into CGS1 nascent peptide showed reduced ability to react with polyethyleneglycol maleimide in the presence of AdoMet, consistent with a shift into the ribosomal exit tunnel. Methylation protection and UV cross-link assays of 28 S rRNA revealed that induced compaction of nascent peptide is associated with specific changes in methylation protection and UV cross-link patterns in the exit tunnel wall. A 14-residue stretch of amino acid sequence, termed the MTO1 region, has been shown to act in cis for CGS1 translation arrest and mRNA degradation. This regulation is lost in the presence of mto1 mutations, which cause single amino acid alterations within MTO1. In this study, both the induced peptide compaction and exit tunnel change were found to be disrupted by mto1 mutations. These results suggest that the MTO1 region participates in the AdoMet-induced arrest of CGS1 translation by mediating changes of the nascent peptide and the exit tunnel wall.
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Affiliation(s)
- Noriyuki Onoue
- Division of Life Science, Graduate School of Life Science, Hokkaido University, Sapporo 060-8589, Japan
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Fukushima A, Kusano M, Redestig H, Arita M, Saito K. Metabolomic correlation-network modules in Arabidopsis based on a graph-clustering approach. BMC SYSTEMS BIOLOGY 2011; 5:1. [PMID: 21194489 PMCID: PMC3030539 DOI: 10.1186/1752-0509-5-1] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 01/01/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Deciphering the metabolome is essential for a better understanding of the cellular metabolism as a system. Typical metabolomics data show a few but significant correlations among metabolite levels when data sampling is repeated across individuals grown under strictly controlled conditions. Although several studies have assessed topologies in metabolomic correlation networks, it remains unclear whether highly connected metabolites in these networks have specific functions in known tissue- and/or genotype-dependent biochemical pathways. RESULTS In our study of metabolite profiles we subjected root tissues to gas chromatography-time-of-flight/mass spectrometry (GC-TOF/MS) and used published information on the aerial parts of 3 Arabidopsis genotypes, Col-0 wild-type, methionine over-accumulation 1 (mto1), and transparent testa4 (tt4) to compare systematically the metabolomic correlations in samples of roots and aerial parts. We then applied graph clustering to the constructed correlation networks to extract densely connected metabolites and evaluated the clusters by biochemical-pathway enrichment analysis. We found that the number of significant correlations varied by tissue and genotype and that the obtained clusters were significantly enriched for metabolites included in biochemical pathways. CONCLUSIONS We demonstrate that the graph-clustering approach identifies tissue- and/or genotype-dependent metabolomic clusters related to the biochemical pathway. Metabolomic correlations complement information about changes in mean metabolite levels and may help to elucidate the organization of metabolically functional modules.
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Huang T, Tohge T, Lytovchenko A, Fernie AR, Jander G. Pleiotropic physiological consequences of feedback-insensitive phenylalanine biosynthesis in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 63:823-35. [PMID: 20598094 DOI: 10.1111/j.1365-313x.2010.04287.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A large proportion of plant carbon flow passes through the shikimate pathway to phenylalanine, which serves as a precursor for numerous secondary metabolites. To identify new regulatory mechanisms affecting phenylalanine metabolism, we isolated Arabidopsis thaliana mutants that are resistant to the phytotoxic amino acid m-tyrosine, a structural analog of phenylalanine. Map-based cloning identified adt2-1D, a dominant point mutation causing a predicted serine to alanine change in the regulatory domain of ADT2 (arogenate dehydratase 2). Relaxed feedback inhibition and increased expression of the mutant enzyme caused up to 160-fold higher accumulation of free phenylalanine in rosette leaves, as well as altered accumulation of several other primary and secondary metabolites. In particular, abundance of 2-phenylethylglucosinolate, which is normally almost undetectable in leaves of the A. thaliana Columbia-0 accession, is increased more than 30-fold. Other observed phenotypes of the adt2-1D mutant include abnormal leaf development, resistance to 5-methyltryptophan, reduced growth of the generalist lepidopteran herbivore Trichoplusia ni (cabbage looper) and increased salt tolerance.
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Affiliation(s)
- Tengfang Huang
- Boyce Thompson Institute for Plant Research, Ithaca, NY 14853, USA
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Kusano M, Fukushima A, Redestig H, Kobayashi M, Otsuki H, Onouchi H, Naito S, Hirai MY, Saito K. Comparative metabolomics charts the impact of genotype-dependent methionine accumulation in Arabidopsis thaliana. Amino Acids 2010; 39:1013-21. [DOI: 10.1007/s00726-010-0562-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 03/09/2010] [Indexed: 12/13/2022]
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Current understanding of the factors regulating methionine content in vegetative tissues of higher plants. Amino Acids 2010; 39:917-31. [DOI: 10.1007/s00726-010-0482-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2009] [Accepted: 01/12/2010] [Indexed: 01/14/2023]
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Jander G, Joshi V. Recent progress in deciphering the biosynthesis of aspartate-derived amino acids in plants. MOLECULAR PLANT 2010; 3:54-65. [PMID: 20019093 DOI: 10.1093/mp/ssp104] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Plants are either directly or indirectly the source of most of the essential amino acids in animal diets. Four of these essential amino acids-methionine, threonine, isoleucine, and lysine-are all produced from aspartate via a well studied biosynthesis pathway. Given the nutritional interest in essential amino acids, the aspartate-derived amino acid pathway has been the subject of extensive research. Additionally, several pathway enzymes serve as targets for economically important herbicides, and some of the downstream products are biosynthetic precursors for other essential plant metabolites such as ethylene and S-adenosylmethionine. Recent and ongoing research on the aspartate-derived family of amino acids has identified new enzyme activities, regulatory mechanisms, and in vivo metabolic functions. Together, these discoveries will open up new possibilities for plant metabolic engineering.
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Affiliation(s)
- Georg Jander
- Boyce Thompson Institute for Plant Research, Ithaca, NY 14850, USA.
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Joshi V, Jander G. Arabidopsis methionine gamma-lyase is regulated according to isoleucine biosynthesis needs but plays a subordinate role to threonine deaminase. PLANT PHYSIOLOGY 2009; 151:367-78. [PMID: 19571310 PMCID: PMC2735994 DOI: 10.1104/pp.109.138651] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Accepted: 06/22/2009] [Indexed: 05/19/2023]
Abstract
The canonical pathway for isoleucine biosynthesis in plants begins with the conversion of threonine to 2-ketobutyrate by threonine deaminase (OMR1). However, demonstration of methionine gamma-lyase (MGL) activity in Arabidopsis (Arabidopsis thaliana) suggested that production of 2-ketobutyrate from methionine can also lead to isoleucine biosynthesis. Rescue of the isoleucine deficit in a threonine deaminase mutant by MGL overexpression, as well as decreased transcription of endogenous Arabidopsis MGL in a feedback-insensitive threonine deaminase mutant background, shows that these two enzymes have overlapping functions in amino acid biosynthesis. In mgl mutant flowers and seeds, methionine levels are significantly increased and incorporation of [(13)C]Met into isoleucine is decreased, but isoleucine levels are unaffected. Accumulation of free isoleucine and other branched-chain amino acids is greatly elevated in response to drought stress in Arabidopsis. Gene expression analyses, amino acid phenotypes, and labeled precursor feeding experiments demonstrate that MGL activity is up-regulated by osmotic stress but likely plays a less prominent role in isoleucine biosynthesis than threonine deaminase. The observation that MGL makes a significant contribution to methionine degradation, particularly in reproductive tissue, suggests practical applications for silencing the expression of MGL in crop plants and thereby increasing the abundance of methionine, a limiting essential amino acid.
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Affiliation(s)
- Vijay Joshi
- Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York 14853, USA
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36
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Nakamichi N, Fukushima A, Kusano M, Sakakibara H, Mizuno T, Saito K. Linkage between circadian clock and tricarboxylic acid cycle in Arabidopsis. PLANT SIGNALING & BEHAVIOR 2009; 4:660-662. [PMID: 19820331 PMCID: PMC2710568 DOI: 10.4161/psb.4.7.9001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Accepted: 05/13/2009] [Indexed: 05/23/2023]
Abstract
The transcriptional/translational feedback loop is thought to play a central role in the circadian clock in Arabidopsis. The loop includes close paralogs of MYB transcription factors CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY), TIMING OF CAB EXPRESSION 1 (TOC1, PSEUDO RESPONSE REGULATOR 1[PRR1]), PRR9, PRR7 and PRR5. The prr9 prr7 prr5 triple mutants (d975) and overexpression line of CCA1 (CCA1-ox) are arrhythmic under continuous light conditions followed by light and dark cycles. We recently demonstrated a tight link between the circadian clock and the tricarboxylic acid (TCA) cycle, from the metabolome analysis of d975. The levels of metabolites belonging to TCA cycle, such as 2-oxoglutarate, succinate, fumarate, citrate and malate increased in d975, whereas those of arginine and ornithine decreased. In this addendum, we further demonstrate that metabolism belonging to TCA cycle in CCA1-ox was partly similar to that of d975. This profiling also supported the linkage between circadian clock and metabolism associated to TCA cycle.
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Affiliation(s)
| | | | - Miyako Kusano
- RIKEN Plant Science Center; Yokohama, Kanagawa Japan
| | | | - Takeshi Mizuno
- School of Agriculture; Nagoya University; Nagoya, Aichi Japan
| | - Kazuki Saito
- RIKEN Plant Science Center; Yokohama, Kanagawa Japan
- Graduate School of Pharmaceutical Sciences; Chiba University; Chiba, Japan
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Sands DC, Pilgeram AL. Methods for selecting hypervirulent biocontrol agents of weeds: why and how. PEST MANAGEMENT SCIENCE 2009; 65:581-587. [PMID: 19288472 DOI: 10.1002/ps.1739] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A considerable number of plant pathogens have been studied for their possible use in weed control. Some have proven virulent enough to control weed species and to compete commercially with chemical herbicides. However, most pathogens of weeds are not useful in their wild form because they are not sufficiently host-specific and/or virulent. The authors believe that these barriers can be overcome. The present research has focused on the inhibitory effects of certain amino acids on the growth and development of specific plants. Pathogens that overproduce these selected amino acids can be easily selected from a pool of spontaneous mutants. Such mutants can have increased pathogenicity to their target weed and enhanced field performance as biocontrol agents. Enhancement of biocontrol efficacy in three separate pathogen-host systems, two with Fusarium and one with Pseudomonas, has already been reported. It is proposed to use the same technology to enhance the biocontrol efficacy of the two species of Fusarium that are host-specific pathogens of the broomrape group of parasitic weeds. The stepwise approach outlined can lead to obtaining enhanced biocontrol agents capable of producing inhibitory levels of selected amino acids in situ. It is proposed that these approaches, in combination with other methods of virulence enhancement, will lead to sustainable systems of biological control of parasitic weeds.
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Affiliation(s)
- David C Sands
- Montana State University, 119 Plant Bioscience Building, Bozeman, MT 59717-3150, USA.
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Impact of clock-associated Arabidopsis pseudo-response regulators in metabolic coordination. Proc Natl Acad Sci U S A 2009; 4:660-2. [PMID: 19359492 DOI: 10.1073/pnas.0900952106] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In higher plants, the circadian clock controls a wide range of cellular processes such as photosynthesis and stress responses. Understanding metabolic changes in arrhythmic plants and determining output-related function of clock genes would help in elucidating circadian-clock mechanisms underlying plant growth and development. In this work, we investigated physiological relevance of PSEUDO-RESPONSE REGULATORS (PRR 9, 7, and 5) in Arabidopsis thaliana by transcriptomic and metabolomic analyses. Metabolite profiling using gas chromatography-time-of-flight mass spectrometry demonstrated well-differentiated metabolite phenotypes of seven mutants, including two arrhythmic plants with similar morphology, a PRR 9, 7, and 5 triple mutant and a CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1)-overexpressor line. Despite different light and time conditions, the triple mutant exhibited a dramatic increase in intermediates in the tricarboxylic acid cycle. This suggests that proteins PRR 9, 7, and 5 are involved in maintaining mitochondrial homeostasis. Integrated analysis of transcriptomics and metabolomics revealed that PRR 9, 7, and 5 negatively regulate the biosynthetic pathways of chlorophyll, carotenoid and abscisic acid, and alpha-tocopherol, highlighting them as additional outputs of pseudo-response regulators. These findings indicated that mitochondrial functions are coupled with the circadian system in plants.
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Jander G, Joshi V. Aspartate-Derived Amino Acid Biosynthesis in Arabidopsis thaliana. THE ARABIDOPSIS BOOK 2009; 7:e0121. [PMID: 22303247 PMCID: PMC3243338 DOI: 10.1199/tab.0121] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The aspartate-derived amino acid pathway in plants leads to the biosynthesis of lysine, methionine, threonine, and isoleucine. These four amino acids are essential in the diets of humans and other animals, but are present in growth-limiting quantities in some of the world's major food crops. Genetic and biochemical approaches have been used for the functional analysis of almost all Arabidopsis thaliana enzymes involved in aspartate-derived amino acid biosynthesis. The branch-point enzymes aspartate kinase, dihydrodipicolinate synthase, homoserine dehydrogenase, cystathionine gamma synthase, threonine synthase, and threonine deaminase contain well-studied sites for allosteric regulation by pathway products and other plant metabolites. In contrast, relatively little is known about the transcriptional regulation of amino acid biosynthesis and the mechanisms that are used to balance aspartate-derived amino acid biosynthesis with other plant metabolic needs. The aspartate-derived amino acid pathway provides excellent examples of basic research conducted with A. thaliana that has been used to improve the nutritional quality of crop plants, in particular to increase the accumulation of lysine in maize and methionine in potatoes.
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Affiliation(s)
- Georg Jander
- Boyce Thompson Institute for Plant Research, Tower Road, Ithaca, NY 14853 USA
- Address correspondence to
| | - Vijay Joshi
- Boyce Thompson Institute for Plant Research, Tower Road, Ithaca, NY 14853 USA
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40
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Yamamoto C, Sakata Y, Taji T, Baba T, Tanaka S. Unique ethylene-regulated touch responses of Arabidopsis thaliana roots to physical hardness. JOURNAL OF PLANT RESEARCH 2008; 121:509-19. [PMID: 18636310 DOI: 10.1007/s10265-008-0178-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2008] [Accepted: 06/09/2008] [Indexed: 05/11/2023]
Abstract
Although touch responses of plant roots are an important adaptive behavior, the molecular mechanism remains unclear. We have developed a bioassay for measuring root-bending responses to physical hardness in Arabidopsis thaliana seedlings. Our test requires a two-layer solid medium. Primary roots growing downward through an upper layer of 0.3% phytagel either penetrate the lower layer or bend along an interface between the upper and lower layers with different concentrations (0.2-0.5%, corresponding to 1.57-6.79 gw mm(-2) in hardness). In proportion to increasing hardness of the lower layer, we found that the percentage of bending roots increased and ethylene production decreased, suggesting an inverse relationship between the root-bending response and ethylene production. Studies with ethylene biosynthesis modulators and mutants also suggested that bending and non-bending responses of roots to medium hardness depend, respectively, on decreased and increased ethylene biosynthesis. In addition, the degrees of root-tip softening and differential root-cell growth, both possible factors determining root-bending response, were enhanced and attenuated by decreased and increased amounts of ethylene, respectively--also in bending roots and non-bending roots. Our findings indicate that ethylene regulates root touch responses, probably through a combination of root-tip softening (or hardening) and differential root-cell growth.
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Affiliation(s)
- Chigusa Yamamoto
- Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502, Japan
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41
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Ufaz S, Galili G. Improving the content of essential amino acids in crop plants: goals and opportunities. PLANT PHYSIOLOGY 2008; 147:954-61. [PMID: 18612072 PMCID: PMC2442549 DOI: 10.1104/pp.108.118091] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Accepted: 03/05/2008] [Indexed: 05/18/2023]
Affiliation(s)
- Shai Ufaz
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
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Dennis ES, Ellis J, Green A, Llewellyn D, Morell M, Tabe L, Peacock W. Genetic contributions to agricultural sustainability. Philos Trans R Soc Lond B Biol Sci 2008; 363:591-609. [PMID: 17656342 PMCID: PMC2610172 DOI: 10.1098/rstb.2007.2172] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The current tools of enquiry into the structure and operation of the plant genome have provided us with an understanding of plant development and function far beyond the state of knowledge that we had previously. We know about key genetic controls repressing or stimulating the cascades of gene expression that move a plant through stages in its life cycle, facilitating the morphogenesis of vegetative and reproductive tissues and organs. The new technologies are enabling the identification of key gene activity responses to the range of biotic and abiotic challenges experienced by plants. In the past, plant breeders produced new varieties with changes in the phases of development, modifications of plant architecture and improved levels of tolerance and resistance to environmental and biotic challenges by identifying the required phenotypes in a few plants among the large numbers of plants in a breeding population. Now our increased knowledge and powerful gene sequence-based diagnostics provide plant breeders with more precise selection objectives and assays to operate in rationally planned crop improvement programmes. We can expect yield potential to increase and harvested product quality portfolios to better fit an increasing diversity of market requirements. The new genetics will connect agriculture to sectors beyond the food, feed and fibre industries; agri-business will contribute to public health and will provide high-value products to the pharmaceutical industry as well as to industries previously based on petroleum feedstocks and chemical modification processes.
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Affiliation(s)
| | | | | | | | | | | | - W.J Peacock
- CSIRO Plant IndustryGPO Box 1600, Canberra, Australian Capital Territory 2601, Australia
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43
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Genetic Engineering of Amino Acid Metabolism in Plants. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1755-0408(07)01003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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Abstract
S-methylmethionine (SMM), a naturally occurring, biologically active compound, is a free amino acid derivative, which is increasingly recognised as playing an important part in the plant metabolism. SMM, which is synthesised from methionine, is involved in crucial processes in the S metabolism, such as the regulation of methionine and S-adenosyl methionine levels, the methylation processes taking place in cells, and the transport and storage of sulphur in certain phases of development. It is of great importance in the development of resistance to abiotic and biotic stress factors, as it is a direct precursor in the biosynthesis of the osmoprotectants and other S-containing compounds involved in defence mechanisms, while also influencing the biosynthesis of major plant hormones such as polyamines and ethylene. The present paper discusses our increasing understanding of the role played by SMM in the plant metabolism and its possible role in the improvement of traits that enable plants to overcome stress.
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Affiliation(s)
- D. Szegő
- 1 Eötvös Loránd University Department of Plant Physiology Budapest Hungary
| | - E. Kósa
- 2 Pannon University Department of Botany and Plant Physiology, Georgikon Faculty Keszthely Hungary
| | - E. Horváth
- 3 Agricultural Research Institute of the Hungarian Academy of Sciences Martonvásár Hungary
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Kusano M, Fukushima A, Arita M, Jonsson P, Moritz T, Kobayashi M, Hayashi N, Tohge T, Saito K. Unbiased characterization of genotype-dependent metabolic regulations by metabolomic approach in Arabidopsis thaliana. BMC SYSTEMS BIOLOGY 2007; 1:53. [PMID: 18028551 PMCID: PMC2233643 DOI: 10.1186/1752-0509-1-53] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Accepted: 11/21/2007] [Indexed: 01/20/2023]
Abstract
BACKGROUND Metabolites are not only the catalytic products of enzymatic reactions but also the active regulators or the ultimate phenotype of metabolic homeostasis in highly complex cellular processes. The modes of regulation at the metabolome level can be revealed by metabolic networks. We investigated the metabolic network between wild-type and 2 mutant (methionine-over accumulation 1 [mto1] and transparent testa4 [tt4]) plants regarding the alteration of metabolite accumulation in Arabidopsis thaliana. RESULTS In the GC-TOF/MS analysis, we acquired quantitative information regarding over 170 metabolites, which has been analyzed by a novel score (ZMC, z-score of metabolite correlation) describing a characteristic metabolite in terms of correlation. Although the 2 mutants revealed no apparent morphological abnormalities, the overall correlation values in mto1 were much lower than those of the wild-type and tt4 plants, indicating the loss of overall network stability due to the uncontrolled accumulation of methionine. In the tt4 mutant, a new correlation between malate and sinapate was observed although the levels of malate, sinapate, and sinapoylmalate remain unchanged, suggesting an adaptive reconfiguration of the network. Gene-expression correlations presumably responsible for these metabolic networks were determined using the metabolite correlations as clues. CONCLUSION Two Arabidopsis mutants, mto1 and tt4, exhibited the following changes in entire metabolome networks: the overall loss of metabolic stability (mto1) or the generation of a metabolic network of a backup pathway for the lost physiological functions (tt4). The expansion of metabolite correlation to gene-expression correlation provides detailed insights into the systemic understanding of the plant cellular process regarding metabolome and transcriptome.
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Affiliation(s)
- Miyako Kusano
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
| | - Atsushi Fukushima
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
| | - Masanori Arita
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
- Department of Computational Biology, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba 277-8561, Japan
| | - Pär Jonsson
- Group for Chemometrics, Organic Chemistry, Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Thomas Moritz
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 87 Umeå, Sweden
| | - Makoto Kobayashi
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
| | - Naomi Hayashi
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
| | - Takayuki Tohge
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
- Max-Planck Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476 Golm-Potsdam, Germany
| | - Kazuki Saito
- RIKEN Plant Science Center, 1-7-22, Yokohama, Kanagawa 230-0045, Japan
- Department of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 263-8522, Japan
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Kojima S, Bohner A, Gassert B, Yuan L, von Wirén N. AtDUR3 represents the major transporter for high-affinity urea transport across the plasma membrane of nitrogen-deficient Arabidopsis roots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 52:30-40. [PMID: 17672841 DOI: 10.1111/j.1365-313x.2007.03223.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Despite the fact that urea is a ubiquitous nitrogen source in soils and the most widespread form of nitrogen fertilizer used in agricultural plant production, membrane transporters that might contribute to the uptake of urea in plant roots have so far been characterized only in heterologous systems. Two T-DNA insertion lines, atdur3-1 and atdur3-3, that showed impaired growth on urea as a sole nitrogen source were used to investigate a role of the H+/urea co-transporter AtDUR3 in nitrogen nutrition in Arabidopsis. In transgenic lines expressing AtDUR3-promoter:GFP constructs, promoter activity was upregulated under nitrogen deficiency and localized to the rhizodermis, including root hairs, as well as to the cortex in more basal root zones. Protein gel blot analysis of two-phase partitioned root membrane fractions and whole-mount immunolocalization in root hairs revealed the plasma membrane to be enriched in AtDUR3 protein. Expression of the AtDUR3 gene in nitrogen-deficient roots was repressed by ammonium and nitrate but induced after supply of urea. Higher accumulation of urea in roots of wild-type plants relative to atdur3-1 and atdur3-3 confirmed that urea was the substrate transported by AtDUR3. Influx of 15N-labeled urea in atdur3-1 and atdur3-3 showed a linear concentration dependency up to 200 microM external urea, whereas influx in wild-type roots followed saturation kinetics with an apparent Km of 4 microM. The results indicate that AtDUR3 is the major transporter for high-affinity urea uptake in Arabidopsis roots and suggest that the high substrate affinity of AtDUR3 reflects an adaptation to the low urea levels usually found in unfertilized soils.
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Affiliation(s)
- Soichi Kojima
- Molecular Plant Nutrition, Institute for Plant Nutrition, University of Hohenheim, D-70593 Stuttgart, Germany
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Higashi Y, Hirai MY, Fujiwara T, Naito S, Noji M, Saito K. Proteomic and transcriptomic analysis of Arabidopsis seeds: molecular evidence for successive processing of seed proteins and its implication in the stress response to sulfur nutrition. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 48:557-71. [PMID: 17059406 DOI: 10.1111/j.1365-313x.2006.02900.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Seed storage proteins are synthesized as sources of carbon, nitrogen and sulfur for the next generation of plants. Their composition changes according to nutritional conditions. Here, we report the precise molecular identification of seed proteins by proteomic analysis of wild-type Arabidopsis thaliana and methionine-over-accumulating mutant mto1-1 plants. The identities of 50 protein spots were determined in the protein extract of mature Arabidopsis seeds by two-dimensional (2D) gel electrophoresis and subsequent mass spectrometric analysis. Of these protein spots, 42 were identified as derived from 12S globulins or 2S albumins. These results indicate that approximately 84% of protein species in Arabidopsis seeds are derived from a few genes coding for 12S globulins and 2S albumins. Extensive mass spectrometric analysis of the 42 spots revealed that successive C-terminal degradation occurred on the 12S globulins. The feasibility of this C-terminal processing was rationalized by molecular modeling of the three-dimensional structure of 12S globulins. The C-terminal degradation at glutamic acid residues of the 12S globulin subunits was repressed under sulfur-deficient conditions. Transcriptome analysis was combined with proteomic analysis to elucidate the mechanism of changes in seed protein composition in response to sulfur deficiency. The results suggest that seed storage proteins in Arabidopsis undergo multi-layer regulation, with emphasis on post-translational modifications that enable the plant to respond to sulfur deficiency.
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Affiliation(s)
- Yasuhiro Higashi
- Department of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Inage-ku, Chiba 263-8522, Japan
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Katz YS, Galili G, Amir R. Regulatory role of cystathionine-gamma-synthase and de novo synthesis of methionine in ethylene production during tomato fruit ripening. PLANT MOLECULAR BIOLOGY 2006; 61:255-68. [PMID: 16786305 DOI: 10.1007/s11103-006-0009-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2005] [Accepted: 01/05/2006] [Indexed: 05/09/2023]
Abstract
The essential amino acid methionine is a substrate for the synthesis of S-adenosyl-methionine (SAM), that donates its methyl group to numerous methylation reactions, and from which polyamines and ethylene are generated. To study the regulatory role of methionine synthesis in tomato fruit ripening, which requires a sharp increase in ethylene production, we cloned a cDNA encoding cystathionine gamma-synthase (CGS) from tomato and analysed its mRNA and protein levels during tomato fruit ripening. CGS mRNA and protein levels peaked at the "turning" stage and declined as the fruit ripened. Notably, the tomato CGS mRNA level in both leaves and fruit was negatively affected by methionine feeding, a regulation that Arabidopsis, but not potato CGS mRNA is subject to. A positive correlation was found between elevated ethylene production and increased CGS mRNA levels during the ethylene burst of the climacteric ripening of tomato fruit. In addition, wounding of pericarp from tomato fruit at the mature green stage stimulated both ethylene production and CGS mRNA level. Application of exogenous methionine to pericarp of mature green fruit increased ethylene evolution, suggesting that soluble methionine may be a rate limiting metabolite for ethylene synthesis. Moreover, treatment of mature green tomato fruit with the ethylene-releasing reagent Ethephon caused an induction of CGS mRNA level, indicating that CGS gene expression is regulated by ethylene. Taken together, these results imply that in addition to recycling of the methionine moieties via the Yang pathway, operating during synthesis of ethylene, de novo synthesis of methionine may be required when high rates of ethylene production are induced.
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Affiliation(s)
- Yael S Katz
- Plant Science Laboratory, Migal Galilee Technological Center, Kiryat Shmona, Israel
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