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Zhang Y, Wang Q, Liu Y, Dong S, Zhang Y, Zhu Y, Tian Y, Li J, Wang Z, Wang Y, Yan F. Overexpressing GmCGS2 Improves Total Amino Acid and Protein Content in Soybean Seed. Int J Mol Sci 2023; 24:14125. [PMID: 37762432 PMCID: PMC10532240 DOI: 10.3390/ijms241814125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 09/10/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Soybean (Glycine max (L.) Merr.) is an important source of plant protein, the nutritional quality of which is considerably affected by the content of the sulfur-containing amino acid, methionine (Met). To improve the quality of soybean protein and increase the Met content in seeds, soybean cystathionine γ-synthase 2 (GmCGS2), the first unique enzyme in Met biosynthesis, was overexpressed in the soybean cultivar "Jack", producing three transgenic lines (OE3, OE4, and OE10). We detected a considerable increase in the content of free Met and other free amino acids in the developing seeds of the three transgenic lines at the 15th and 75th days after flowering (15D and 75D). In addition, transcriptome analysis showed that the expression of genes related to Met biosynthesis from the aspartate-family pathway and S-methyl Met cycle was promoted in developing green seeds of OE10. Ultimately, the accumulation of total amino acids and soluble proteins in transgenic mature seeds was promoted. Altogether, these results indicated that GmCGS2 plays an important role in Met biosynthesis, by providing a basis for improving the nutritional quality of soybean seeds.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Fan Yan
- Correspondence: (Y.W.); (F.Y.)
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2
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Pandey J, Thompson D, Joshi M, Scheuring DC, Koym JW, Joshi V, Vales MI. Genetic architecture of tuber-bound free amino acids in potato and effect of growing environment on the amino acid content. Sci Rep 2023; 13:13940. [PMID: 37626106 PMCID: PMC10457394 DOI: 10.1038/s41598-023-40880-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
Free amino acids in potato tubers contribute to their nutritional value and processing quality. Exploring the natural variation in their accumulation in tubers across diverse genetic backgrounds is critical to potato breeding programs aiming to enhance or partition their distribution effectively. This study assessed variation in the tuber-bound free amino acids in a diversity panel of tetraploid potato clones developed and maintained by the Texas A&M Potato Breeding Program to explore their genetic basis and to obtain genomic-estimated breeding values for applied breeding purposes. Free amino acids content was evaluated in tubers of 217 tetraploid potato clones collected from Dalhart, Texas in 2019 and 2020, and Springlake, Texas in 2020. Most tuber amino acids were not affected by growing location, except histidine and proline, which were significantly lower (- 59.0%) and higher (+ 129.0%), respectively, at Springlake, Texas (a location that regularly suffers from abiotic stresses, mainly high-temperature stress). Single nucleotide polymorphism markers were used for genome-wide association studies and genomic selection of clones based on amino acid content. Most amino acids showed significant variations among potato clones and moderate to high heritabilities. Principal component analysis separated fresh from processing potato market classes based on amino acids distribution patterns. Genome-wide association studies discovered 33 QTL associated with 13 free amino acids. Genomic-estimated breeding values were calculated and are recommended for practical potato breeding applications to select parents and advance clones with the desired free amino acid content.
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Affiliation(s)
- Jeewan Pandey
- Department of Horticultural Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Dalton Thompson
- Texas A&M AgriLife Research and Extension Center, Uvalde, TX, 78801, USA
| | - Madhumita Joshi
- Texas A&M AgriLife Research and Extension Center, Uvalde, TX, 78801, USA
| | - Douglas C Scheuring
- Department of Horticultural Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Jeffrey W Koym
- Texas A&M AgriLife Research and Extension Center, Lubbock, TX, 79403, USA
| | - Vijay Joshi
- Department of Horticultural Sciences, Texas A&M University, College Station, TX, 77843, USA.
- Texas A&M AgriLife Research and Extension Center, Uvalde, TX, 78801, USA.
| | - M Isabel Vales
- Department of Horticultural Sciences, Texas A&M University, College Station, TX, 77843, USA.
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3
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Whitcomb SJ, Rakpenthai A, Brückner F, Fischer A, Parmar S, Erban A, Kopka J, Hawkesford MJ, Hoefgen R. Cysteine and Methionine Biosynthetic Enzymes Have Distinct Effects on Seed Nutritional Quality and on Molecular Phenotypes Associated With Accumulation of a Methionine-Rich Seed Storage Protein in Rice. FRONTIERS IN PLANT SCIENCE 2020; 11:1118. [PMID: 32793268 PMCID: PMC7387578 DOI: 10.3389/fpls.2020.01118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/07/2020] [Indexed: 06/11/2023]
Abstract
Staple crops in human and livestock diets suffer from deficiencies in certain "essential" amino acids including methionine. With the goal of increasing methionine in rice seed, we generated a pair of "Push × Pull" double transgenic lines, each containing a methionine-dense seed storage protein (2S albumin from sunflower, HaSSA) and an exogenous enzyme for either methionine (feedback desensitized cystathionine gamma synthase from Arabidopsis, AtD-CGS) or cysteine (serine acetyltransferase from E. coli, EcSAT) biosynthesis. In both double transgenic lines, the total seed methionine content was approximately 50% higher than in their untransformed parental line, Oryza sativa ssp. japonica cv. Taipei 309. HaSSA-containing rice seeds were reported to display an altered seed protein profile, speculatively due to insufficient sulfur amino acid content. However, here we present data suggesting that this may result from an overloaded protein folding machinery in the endoplasmic reticulum rather than primarily from redistribution of limited methionine from endogenous seed proteins to HaSSA. We hypothesize that HaSSA-associated endoplasmic reticulum stress results in redox perturbations that negatively impact sulfate reduction to cysteine, and we speculate that this is mitigated by EcSAT-associated increased sulfur import into the seed, which facilitates additional synthesis of cysteine and glutathione. The data presented here reveal challenges associated with increasing the methionine content in rice seed, including what may be relatively low protein folding capacity in the endoplasmic reticulum and an insufficient pool of sulfate available for additional cysteine and methionine synthesis. We propose that future approaches to further improve the methionine content in rice should focus on increasing seed sulfur loading and avoiding the accumulation of unfolded proteins in the endoplasmic reticulum. Oryza sativa ssp. japonica: urn:lsid:ipni.org:names:60471378-2.
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Affiliation(s)
- Sarah J. Whitcomb
- Laboratory of Amino Acid and Sulfur Metabolism, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Apidet Rakpenthai
- Laboratory of Amino Acid and Sulfur Metabolism, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Franziska Brückner
- Laboratory of Amino Acid and Sulfur Metabolism, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Axel Fischer
- Bioinformatics Infrastructure Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Saroj Parmar
- Plant Sciences Department, Rothamsted Research, Harpenden, United Kingdom
| | - Alexander Erban
- Applied Metabolome Analysis Infrastructure Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Joachim Kopka
- Applied Metabolome Analysis Infrastructure Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | | | - Rainer Hoefgen
- Laboratory of Amino Acid and Sulfur Metabolism, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
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4
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Singh H, Tiwari K, Tiwari R, Pramanik SK, Das A. Small Molecule as Fluorescent Probes for Monitoring Intracellular Enzymatic Transformations. Chem Rev 2019; 119:11718-11760. [DOI: 10.1021/acs.chemrev.9b00379] [Citation(s) in RCA: 162] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Harwinder Singh
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Karishma Tiwari
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Rajeshwari Tiwari
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Sumit Kumar Pramanik
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Amitava Das
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
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5
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Bai Z, Qi T, Liu Y, Wu Z, Ma L, Liu W, Cao Y, Bao Y, Fu C. Alteration of S-adenosylhomocysteine levels affects lignin biosynthesis in switchgrass. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:2016-2026. [PMID: 29704888 PMCID: PMC6230947 DOI: 10.1111/pbi.12935] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/05/2018] [Accepted: 04/11/2018] [Indexed: 05/18/2023]
Abstract
Methionine (Met) synthesized from aspartate is a fundamental amino acid needed to produce S-adenosylmethionine (SAM) that is an important cofactor for the methylation of monolignols. As a competitive inhibitor of SAM-dependent methylation, the effect of S-adenosylhomocysteine (SAH) on lignin biosynthesis, however, is still largely unknown in plants. Expression levels of Cystathionine γ-synthase (PvCGS) and S-adenosylhomocysteine hydrolase 1 (PvSAHH1) were down-regulated by RNAi technology, respectively, in switchgrass, a dual-purpose forage and biofuel crop. The transgenic switchgrass lines were subjected to studying the impact of SAH on lignin biosynthesis. Our results showed that down-regulation of PvCGS in switchgrass altered the accumulation of aspartate-derived and aromatic amino acids, reduced the content of SAH, enhanced lignin biosynthesis and stunted plant growth. In contrast, down-regulation of PvSAHH1 raised SAH levels in switchgrass, impaired the biosynthesis of both guaiacyl and syringyl lignins and therefore significantly increased saccharification efficiency of cell walls. This work indicates that SAH plays a crucial role in monolignol methylation in switchgrass. Genetic regulation of either PvCGS or PvSAHH1 expression in switchgrass can change intracellular SAH contents and SAM to SAH ratios and therefore affect lignin biosynthesis. Thus, our study suggests that genes involved in Met metabolism are of interest as new valuable targets for cell wall bioengineering in future.
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Affiliation(s)
- Zetao Bai
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Tianxiong Qi
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Yuchen Liu
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Zhenying Wu
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Lichao Ma
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Wenwen Liu
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Yingping Cao
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Yan Bao
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Chunxiang Fu
- Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Key Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
- Qingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
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6
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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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7
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Xiang X, Wu Y, Planta J, Messing J, Leustek T. Overexpression of serine acetyltransferase in maize leaves increases seed-specific methionine-rich zeins. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:1057-1067. [PMID: 29044890 PMCID: PMC5902772 DOI: 10.1111/pbi.12851] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/22/2017] [Accepted: 10/09/2017] [Indexed: 05/19/2023]
Abstract
Maize kernels do not contain enough of the essential sulphur-amino acid methionine (Met) to serve as a complete diet for animals, even though maize has the genetic capacity to store Met in kernels. Prior studies indicated that the availability of the sulphur (S)-amino acids may limit their incorporation into seed storage proteins. Serine acetyltransferase (SAT) is a key control point for S-assimilation leading to Cys and Met biosynthesis, and SAT overexpression is known to enhance S-assimilation without negative impact on plant growth. Therefore, we overexpressed Arabidopsis thaliana AtSAT1 in maize under control of the leaf bundle sheath cell-specific rbcS1 promoter to determine the impact on seed storage protein expression. The transgenic events exhibited up to 12-fold higher SAT activity without negative impact on growth. S-assimilation was increased in the leaves of SAT overexpressing plants, followed by higher levels of storage protein mRNA and storage proteins, particularly the 10-kDa δ-zein, during endosperm development. This zein is known to impact the level of Met stored in kernels. The elite event with the highest expression of AtSAT1 showed 1.40-fold increase in kernel Met. When fed to chickens, transgenic AtSAT1 kernels significantly increased growth rate compared with the parent maize line. The result demonstrates the efficacy of increasing maize nutritional value by SAT overexpression without apparent yield loss. Maternal overexpression of SAT in vegetative tissues was necessary for high-Met zein accumulation. Moreover, SAT overcomes the shortage of S-amino acids that limits the expression and accumulation of high-Met zeins during kernel development.
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Affiliation(s)
- Xiaoli Xiang
- Department of Plant BiologyRutgers UniversityNew BrunswickNJUSA
- Institute of Biotechnology and Nuclear TechnologySichuan Academy of Agricultural SciencesChengduChina
| | - Yongrui Wu
- National Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology & EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
- Waksman Institute of MicrobiologyRutgers UniversityPiscatawayNJUSA
| | - José Planta
- Waksman Institute of MicrobiologyRutgers UniversityPiscatawayNJUSA
| | - Joachim Messing
- Waksman Institute of MicrobiologyRutgers UniversityPiscatawayNJUSA
| | - Thomas Leustek
- Department of Plant BiologyRutgers UniversityNew BrunswickNJUSA
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8
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Planta J, Xiang X, Leustek T, Messing J. Engineering sulfur storage in maize seed proteins without apparent yield loss. Proc Natl Acad Sci U S A 2017; 114:11386-11391. [PMID: 29073061 PMCID: PMC5664557 DOI: 10.1073/pnas.1714805114] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sulfur assimilation may limit the pool of methionine and cysteine available for incorporation into zeins, the major seed storage proteins in maize. This hypothesis was tested by producing transgenic maize with deregulated sulfate reduction capacity achieved through leaf-specific expression of the Escherichia coli enzyme 3'-phosphoadenosine-5'-phosphosulfate reductase (EcPAPR) that resulted in higher methionine accumulation in seeds. The transgenic kernels have higher expression of the methionine-rich 10-kDa δ-zein and total protein sulfur without reduction of other zeins. This overall increase in the expression of the S-rich zeins describes a facet of regulation of these proteins under enhanced sulfur assimilation. Transgenic line PE5 accumulates 57.6% more kernel methionine than the high-methionine inbred line B101. In feeding trials with chicks, PE5 maize promotes significant weight gain compared with nontransgenic kernels. Therefore, increased source strength can improve the nutritional value of maize without apparent yield loss and may significantly reduce the cost of feed supplementation.
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Affiliation(s)
- Jose Planta
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854
| | - Xiaoli Xiang
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901
- Institute of Biotechnology and Nuclear Technology, Sichuan Academy of Agricultural Sciences, Chengdu 610061, China
| | - Thomas Leustek
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901
| | - Joachim Messing
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854;
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Kumar P, Jander G. Concurrent Overexpression of Arabidopsis thaliana Cystathionine γ-Synthase and Silencing of Endogenous Methionine γ-Lyase Enhance Tuber Methionine Content in Solanum tuberosum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:2737-2742. [PMID: 28294619 DOI: 10.1021/acs.jafc.7b00272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Potatoes (Solanum tuberosum) are deficient in methionine, an essential amino acid in human and animal diets. Higher methionine levels increase the nutritional quality and promote the typically pleasant aroma associated with baked and fried potatoes. Several attempts have been made to elevate tuber methionine levels by genetic engineering of methionine biosynthesis and catabolism. Overexpressing Arabidopsis thaliana cystathionine γ-synthase (AtCGS) in S. tuberosum up-regulates a rate-limiting step of methionine biosynthesis and increases tuber methionine levels. Alternatively, silencing S. tuberosum methionine γ-lyase (StMGL), which causes decreased degradation of methionine into 2-ketobutyrate, also increases methionine levels. Concurrently enhancing biosynthesis and reducing degradation were predicted to provide further increases in tuber methionine content. Here we report that S. tuberosum cv. Désirée plants with AtCGS overexpression and StMGL silenced by RNA interference are morphologically normal and accumulate higher free methionine levels than either single-transgenic line.
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Affiliation(s)
- Pavan Kumar
- Boyce Thompson Institute for Plant Research , 533 Tower Road, Ithaca, New York 14853, United States
| | - Georg Jander
- Boyce Thompson Institute for Plant Research , 533 Tower Road, Ithaca, New York 14853, United States
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10
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Rahikainen M, Trotta A, Alegre S, Pascual J, Vuorinen K, Overmyer K, Moffatt B, Ravanel S, Glawischnig E, Kangasjärvi S. PP2A-B'γ modulates foliar trans-methylation capacity and the formation of 4-methoxy-indol-3-yl-methyl glucosinolate in Arabidopsis leaves. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 89:112-127. [PMID: 27598402 DOI: 10.1111/tpj.13326] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 08/31/2016] [Accepted: 09/01/2016] [Indexed: 05/27/2023]
Abstract
Glucosinolates (GSL) of cruciferous plants comprise a major group of structurally diverse secondary compounds which act as deterrents against aphids and microbial pathogens and have large commercial and ecological impacts. While the transcriptional regulation governing the biosynthesis and modification of GSL is now relatively well understood, post-translational regulatory components that specifically determine the structural variation of indole glucosinolates have not been reported. We show that the cytoplasmic protein phosphatase 2A regulatory subunit B'γ (PP2A-B'γ) physically interacts with indole glucosinolate methyltransferases and controls the methoxylation of indole glucosinolates and the formation of 4-methoxy-indol-3-yl-methyl glucosinolate in Arabidopsis leaves. By taking advantage of proteomic approaches and metabolic analysis we further demonstrate that PP2A-B'γ is required to control the abundance of oligomeric protein complexes functionally linked with the activated methyl cycle and the trans-methylation capacity of leaf cells. These findings highlight the key regulatory role of PP2A-B'γ in methionine metabolism and provide a previously unrecognized perspective for metabolic engineering of glucosinolate metabolism in cruciferous plants.
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Affiliation(s)
- Moona Rahikainen
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Andrea Trotta
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Sara Alegre
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Jesús Pascual
- Plant Physiology Lab, Organisms and Systems Biology, Faculty of Biology, University of Oviedo, Oviedo, Asturias, Spain
| | - Katariina Vuorinen
- Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Kirk Overmyer
- Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Barbara Moffatt
- Department of Biology, University of Waterloo, 200 University Avenue, Ontario, N2L 3G1, Canada
| | - Stéphane Ravanel
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS UMR5168, INRA UMR1417, CEA, Université Grenoble Alpes, 38054, Grenoble, France
| | - Erich Glawischnig
- Department of Plant Sciences, Technische Universität München, Emil-Ramann-Str.4, 85354, Freising, Germany
| | - Saijaliisa Kangasjärvi
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
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11
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Koprivova A, Kopriva S. Sulfur metabolism and its manipulation in crops. J Genet Genomics 2016; 43:623-629. [PMID: 27582269 DOI: 10.1016/j.jgg.2016.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/12/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Anna Koprivova
- Botanical Institute and Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany
| | - Stanislav Kopriva
- Botanical Institute and Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany.
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Zuchi S, Watanabe M, Hubberten HM, Bromke M, Osorio S, Fernie AR, Celletti S, Paolacci AR, Catarcione G, Ciaffi M, Hoefgen R, Astolfi S. The Interplay between Sulfur and Iron Nutrition in Tomato. PLANT PHYSIOLOGY 2015; 169:2624-39. [PMID: 26438787 PMCID: PMC4677893 DOI: 10.1104/pp.15.00995] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/02/2015] [Indexed: 05/20/2023]
Abstract
Plant response mechanisms to deficiency of a single nutrient, such as sulfur (S) or iron (Fe), have been described at agronomic, physiological, biochemical, metabolomics, and transcriptomic levels. However, agroecosystems are often characterized by different scenarios, in which combined nutrient deficiencies are likely to occur. Soils are becoming depleted for S, whereas Fe, although highly abundant in the soil, is poorly available for uptake because of its insolubility in the soil matrix. To this end, earlier reports showed that a limited S availability reduces Fe uptake and that Fe deficiency results in the modulation of sulfate uptake and assimilation. However, the mechanistic basis of this interaction remains largely unknown. Metabolite profiling of tomato (Solanum lycopersicum) shoots and roots from plants exposed to Fe, S, and combined Fe and S deficiency was performed to improve the understanding of the S-Fe interaction through the identification of the main players in the considered pathways. Distinct changes were revealed under the different nutritional conditions. Furthermore, we investigated the development of the Fe deficiency response through the analysis of expression of ferric chelate reductase, iron-regulated transporter, and putative transcription factor genes and plant sulfate uptake and mobilization capacity by analyzing the expression of genes encoding sulfate transporters (STs) of groups 1, 2, and 4 (SlST1.1, SlST1.2, SlST2.1, SlST2.2, and SlST4.1). We identified a high degree of common and even synergistic response patterns as well as nutrient-specific responses. The results are discussed in the context of current models of nutrient deficiency responses in crop plants.
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Affiliation(s)
- Sabrina Zuchi
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Mutsumi Watanabe
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Hans-Michael Hubberten
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Mariusz Bromke
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Sonia Osorio
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Alisdair R Fernie
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Silvia Celletti
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Anna Rita Paolacci
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Giulio Catarcione
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Mario Ciaffi
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Rainer Hoefgen
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
| | - Stefania Astolfi
- Department of Agricultural and Forestry Sciences (S.Z., S.C., A.R.P., S.A.) and Department for Innovation in Biological, Agrofood, and Forest Systems (G.C., M.C.), University of Tuscia, 01100 Viterbo, Italy;Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany (M.W., H.-M.H., M.B., A.R.F., R.H.); andDepartment of Molecular Biology and Biochemistry, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," University of Malaga, Consejo Superior de Investigaciones Científicas, 29071 Malaga, Spain (S.O.)
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Tomanov K, Zeschmann A, Hermkes R, Eifler K, Ziba I, Grieco M, Novatchkova M, Hofmann K, Hesse H, Bachmair A. Arabidopsis PIAL1 and 2 promote SUMO chain formation as E4-type SUMO ligases and are involved in stress responses and sulfur metabolism. THE PLANT CELL 2014; 26:4547-60. [PMID: 25415977 PMCID: PMC4277223 DOI: 10.1105/tpc.114.131300] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 10/20/2014] [Accepted: 11/01/2014] [Indexed: 05/18/2023]
Abstract
The Arabidopsis thaliana genes PROTEIN INHIBITOR OF ACTIVATED STAT LIKE1 (PIAL1) and PIAL2 encode proteins with SP-RING domains, which occur in many ligases of the small ubiquitin-related modifier (SUMO) conjugation pathway. We show that PIAL1 and PIAL2 function as SUMO ligases capable of SUMO chain formation and require the SUMO-modified SUMO-conjugating enzyme SCE1 for optimal activity. Mutant analysis indicates a role for PIAL1 and 2 in salt stress and osmotic stress responses, whereas under standard conditions, the mutants show close to normal growth. Mutations in PIAL1 and 2 also lead to altered sulfur metabolism. We propose that, together with SUMO chain binding ubiquitin ligases, these enzymes establish a pathway for proteolytic removal of sumoylation substrates.
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Affiliation(s)
- Konstantin Tomanov
- Max F. Perutz Laboratories, Center for Molecular Biology of the University of Vienna, A-1030 Vienna, Austria
| | - Anja Zeschmann
- Department of Molecular Plant Physiology, Max Planck Institute for Molecular Plant Physiology, D-14476 Potsdam, Germany
| | - Rebecca Hermkes
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Karolin Eifler
- Max F. Perutz Laboratories, Center for Molecular Biology of the University of Vienna, A-1030 Vienna, Austria Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
| | - Ionida Ziba
- Max F. Perutz Laboratories, Center for Molecular Biology of the University of Vienna, A-1030 Vienna, Austria
| | - Michele Grieco
- Department of Ecogenomics and Systems Biology, University of Vienna, A-1090 Vienna, Austria
| | | | - Kay Hofmann
- Institute for Genetics, University of Cologne, D-50674 Cologne, Germany
| | - Holger Hesse
- Department of Molecular Plant Physiology, Max Planck Institute for Molecular Plant Physiology, D-14476 Potsdam, Germany
| | - Andreas Bachmair
- Max F. Perutz Laboratories, Center for Molecular Biology of the University of Vienna, A-1030 Vienna, Austria Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany
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14
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Huang T, Joshi V, Jander G. The catabolic enzyme methionine gamma-lyase limits methionine accumulation in potato tubers. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:883-93. [PMID: 24738868 DOI: 10.1111/pbi.12191] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 03/07/2014] [Accepted: 03/17/2014] [Indexed: 05/07/2023]
Abstract
Increasing methionine in potato tubers is desirable, both to increase the availability of this limiting essential amino acid and to enhance the aroma of baked and fried potatoes. Previous attempts to elevate potato methionine content using transgenic approaches have focused on increasing methionine biosynthesis. Higher isoleucine accumulation in these transgenic tubers suggested that the potatoes compensate for increased methionine biosynthesis with enhanced catabolism via methionine gamma-lyase (MGL), thereby producing 2-ketybutyrate for isoleucine biosynthesis. In the current study, we show that potato StMGL1 encodes a functional MGL in potato tubers. In planta silencing of StMGL1 results in an increased methionine to isoleucine ratio in the free amino acid profile of potato tubers and, in some transgenic lines, elevated accumulation of free methionine. In both wild-type and transgenic tubers, the ratio of methionine to isoleucine is negatively correlated with the level of StMGL1 transcript. A three-dimensional distribution of free amino acids in potato tubers is also described.
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Affiliation(s)
- Tengfang Huang
- Boyce Thompson Institute for Plant Research, Ithaca, NY, USA
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15
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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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Bielecka M, Watanabe M, Morcuende R, Scheible WR, Hawkesford MJ, Hesse H, Hoefgen R. Transcriptome and metabolome analysis of plant sulfate starvation and resupply provides novel information on transcriptional regulation of metabolism associated with sulfur, nitrogen and phosphorus nutritional responses in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2014; 5:805. [PMID: 25674096 PMCID: PMC4309162 DOI: 10.3389/fpls.2014.00805] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/22/2014] [Indexed: 05/22/2023]
Abstract
Sulfur is an essential macronutrient for plant growth and development. Reaching a thorough understanding of the molecular basis for changes in plant metabolism depending on the sulfur-nutritional status at the systems level will advance our basic knowledge and help target future crop improvement. Although the transcriptional responses induced by sulfate starvation have been studied in the past, knowledge of the regulation of sulfur metabolism is still fragmentary. This work focuses on the discovery of candidates for regulatory genes such as transcription factors (TFs) using 'omics technologies. For this purpose a short term sulfate-starvation/re-supply approach was used. ATH1 microarray studies and metabolite determinations yielded 21 TFs which responded more than 2-fold at the transcriptional level to sulfate starvation. Categorization by response behaviors under sulfate-starvation/re-supply and other nutrient starvations such as nitrate and phosphate allowed determination of whether the TF genes are specific for or common between distinct mineral nutrient depletions. Extending this co-behavior analysis to the whole transcriptome data set enabled prediction of putative downstream genes. Additionally, combinations of transcriptome and metabolome data allowed identification of relationships between TFs and downstream responses, namely, expression changes in biosynthetic genes and subsequent metabolic responses. Effect chains on glucosinolate and polyamine biosynthesis are discussed in detail. The knowledge gained from this study provides a blueprint for an integrated analysis of transcriptomics and metabolomics and application for the identification of uncharacterized genes.
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Affiliation(s)
- Monika Bielecka
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Wroclaw Medical UniversityWroclaw, Poland
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Mutsumi Watanabe
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Rosa Morcuende
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
- Institute of Natural Resources and Agrobiology of Salamanca, Consejo Superior de Investigaciones CientíficasSalamanca, Spain
| | - Wolf-Rüdiger Scheible
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
- Plant Biology Division, The Samuel Roberts Noble FoundationArdmore, OK, USA
| | | | - Holger Hesse
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Rainer Hoefgen
- Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
- *Correspondence: Rainer Hoefgen, Max-Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany e-mail:
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Bielecka M, Watanabe M, Morcuende R, Scheible WR, Hawkesford MJ, Hesse H, Hoefgen R. Transcriptome and metabolome analysis of plant sulfate starvation and resupply provides novel information on transcriptional regulation of metabolism associated with sulfur, nitrogen and phosphorus nutritional responses in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2014. [PMID: 25674096 DOI: 10.1007/s11105-014-0772-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Sulfur is an essential macronutrient for plant growth and development. Reaching a thorough understanding of the molecular basis for changes in plant metabolism depending on the sulfur-nutritional status at the systems level will advance our basic knowledge and help target future crop improvement. Although the transcriptional responses induced by sulfate starvation have been studied in the past, knowledge of the regulation of sulfur metabolism is still fragmentary. This work focuses on the discovery of candidates for regulatory genes such as transcription factors (TFs) using 'omics technologies. For this purpose a short term sulfate-starvation/re-supply approach was used. ATH1 microarray studies and metabolite determinations yielded 21 TFs which responded more than 2-fold at the transcriptional level to sulfate starvation. Categorization by response behaviors under sulfate-starvation/re-supply and other nutrient starvations such as nitrate and phosphate allowed determination of whether the TF genes are specific for or common between distinct mineral nutrient depletions. Extending this co-behavior analysis to the whole transcriptome data set enabled prediction of putative downstream genes. Additionally, combinations of transcriptome and metabolome data allowed identification of relationships between TFs and downstream responses, namely, expression changes in biosynthetic genes and subsequent metabolic responses. Effect chains on glucosinolate and polyamine biosynthesis are discussed in detail. The knowledge gained from this study provides a blueprint for an integrated analysis of transcriptomics and metabolomics and application for the identification of uncharacterized genes.
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Affiliation(s)
- Monika Bielecka
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Wroclaw Medical University Wroclaw, Poland ; Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany
| | - Mutsumi Watanabe
- Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany
| | - Rosa Morcuende
- Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany ; Institute of Natural Resources and Agrobiology of Salamanca, Consejo Superior de Investigaciones Científicas Salamanca, Spain
| | - Wolf-Rüdiger Scheible
- Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany ; Plant Biology Division, The Samuel Roberts Noble Foundation Ardmore, OK, USA
| | | | - Holger Hesse
- Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany
| | - Rainer Hoefgen
- Max-Planck Institute of Molecular Plant Physiology Potsdam-Golm, Germany
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Matityahu I, Godo I, Hacham Y, Amir R. Tobacco seeds expressing feedback-insensitive cystathionine gamma-synthase exhibit elevated content of methionine and altered primary metabolic profile. BMC PLANT BIOLOGY 2013; 13:206. [PMID: 24314105 PMCID: PMC3878949 DOI: 10.1186/1471-2229-13-206] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 12/03/2013] [Indexed: 05/03/2023]
Abstract
BACKGROUND The essential sulfur-containing amino acid methionine plays a vital role in plant metabolism and human nutrition. In this study, we aimed to elucidate the regulatory role of the first committed enzyme in the methionine biosynthesis pathway, cystathionine γ-synthase (CGS), on methionine accumulation in tobacco seeds. We also studied the effect of this manipulation on the seed's metabolism. RESULTS Two forms of Arabidopsis CGS (AtCGS) were expressed under the control of the seeds-specific promoter of legumin B4: feedback-sensitive F-AtCGS (LF seeds), and feedback-insensitive T-AtCGS (LT seeds). Unexpectedly, the soluble content of methionine was reduced significantly in both sets of transgenic seeds. Amino acids analysis and feeding experiments indicated that although the level of methionine was reduced, the flux through its synthesis had increased. As a result, the level of protein-incorporated methionine had increased significantly in LT seeds by up to 60%, but this was not observed in LF seeds, whose methionine content is tightly regulated. This increase was accompanied by a higher content of other protein-incorporated amino acids, which led to 27% protein content in the seeds although this was statistically insignificantly. In addition, the levels of reducing sugars (representing starch) were slightly but significantly reduced, while that of oil was insignificantly reduced. To assess the impact of the high expression level of T-AtCGS in seeds on other primary metabolites, metabolic profiling using GC-MS was performed. This revealed significant alterations to the primary seed metabolism manifested by a significant increase in eight annotated metabolites (mostly sugars and their oxidized derivatives), while the levels of 12 other metabolites were reduced significantly in LT compared to wild-type seeds. CONCLUSION Expression of T-AtCGS leads to an increase in the level of total Met, higher contents of total amino acids, and significant changes in the levels of 20 annotated metabolites. The high level of oxidized metabolites, the two stress-associated amino acids, proline and serine, and low level of glutathione suggest oxidative stress that occurs during LT seed development. This study provides information on the metabolic consequence of increased CGS activity in seeds and how it affects the seed's nutritional quality.
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Affiliation(s)
- Ifat Matityahu
- Laboratory of Plant Science, Migal Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
| | - Itamar Godo
- Laboratory of Plant Science, Migal Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
| | - Yael Hacham
- Laboratory of Plant Science, Migal Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
| | - Rachel Amir
- Laboratory of Plant Science, Migal Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12100, Israel
- Tel Hai College, Upper Galilee, Israel
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19
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Sanchez-Villarreal A, Shin J, Bujdoso N, Obata T, Neumann U, Du SX, Ding Z, Davis AM, Shindo T, Schmelzer E, Sulpice R, Nunes-Nesi A, Stitt M, Fernie AR, Davis SJ. TIME FOR COFFEE is an essential component in the maintenance of metabolic homeostasis in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 76:188-200. [PMID: 23869666 DOI: 10.1111/tpj.12292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Revised: 06/12/2013] [Accepted: 07/02/2013] [Indexed: 05/08/2023]
Abstract
Plants often respond to environmental changes by reprogramming metabolic and stress-associated pathways. Homeostatic integration of signaling is a central requirement for ensuring metabolic stability in living organisms. Under diurnal conditions, properly timed rhythmic metabolism provides fitness benefits to plants. TIME FOR COFFEE (TIC) is a circadian regulator known to be involved in clock resetting at dawn. Here we explored the mechanism of influence of TIC in plant growth and development, as initiated by a microarray analysis. This global profiling showed that a loss of TIC function causes a major reprogramming of gene expression that predicts numerous developmental, metabolic, and stress-related phenotypes. This led us to demonstrate that this mutant exhibits late flowering, a plastochron defect, and diverse anatomical phenotypes. We further observed a starch-excess phenotype and altered soluble carbohydrate levels. tic exhibited hypersensitivity to oxidative stress and abscisic acid, and this was associated with a striking resistance to drought. These phenotypes were connected to an increase in total glutathione levels that correlated with a readjustment of amino acids and polyamine pools. By comparatively analyzing our transcriptomic and metabolomic data, we concluded that TIC is a central element in plant homeostasis that integrates and coordinates developmental, metabolic, and environmental signals.
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Affiliation(s)
- Alfredo Sanchez-Villarreal
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, 50829, Cologne, Germany
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Hacham Y, Matityahu I, Amir R. Light and sucrose up-regulate the expression level of Arabidopsis cystathionine γ-synthase, the key enzyme of methionine biosynthesis pathway. Amino Acids 2013; 45:1179-90. [DOI: 10.1007/s00726-013-1576-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 08/02/2013] [Indexed: 10/26/2022]
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21
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Schmidt R, Mieulet D, Hubberten HM, Obata T, Hoefgen R, Fernie AR, Fisahn J, San Segundo B, Guiderdoni E, Schippers JH, Mueller-Roeber B. Salt-responsive ERF1 regulates reactive oxygen species-dependent signaling during the initial response to salt stress in rice. THE PLANT CELL 2013; 25:2115-31. [PMID: 23800963 PMCID: PMC3723616 DOI: 10.1105/tpc.113.113068] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 05/13/2013] [Accepted: 06/02/2013] [Indexed: 05/19/2023]
Abstract
Early detection of salt stress is vital for plant survival and growth. Still, the molecular processes controlling early salt stress perception and signaling are not fully understood. Here, we identified salt-responsive ERF1 (SERF1), a rice (Oryza sativa) transcription factor (TF) gene that shows a root-specific induction upon salt and hydrogen peroxide (H2O2) treatment. Loss of SERF1 impairs the salt-inducible expression of genes encoding members of a mitogen-activated protein kinase (MAPK) cascade and salt tolerance-mediating TFs. Furthermore, we show that SERF1-dependent genes are H2O2 responsive and demonstrate that SERF1 binds to the promoters of MAPK kinase kinase6 (MAP3K6), MAPK5, dehydration-responsive element bindinG2A (DREB2A), and zinc finger protein179 (ZFP179) in vitro and in vivo. SERF1 also directly induces its own gene expression. In addition, SERF1 is a phosphorylation target of MAPK5, resulting in enhanced transcriptional activity of SERF1 toward its direct target genes. In agreement, plants deficient for SERF1 are more sensitive to salt stress compared with the wild type, while constitutive overexpression of SERF1 improves salinity tolerance. We propose that SERF1 amplifies the reactive oxygen species-activated MAPK cascade signal during the initial phase of salt stress and translates the salt-induced signal into an appropriate expressional response resulting in salt tolerance.
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Affiliation(s)
- Romy Schmidt
- Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Delphine Mieulet
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixte de Recherche, Genetic Improvement and Adaptation of Mediterranean and Tropical Plants, 34398 Montpellier, cedex 5, France
| | | | - Toshihiro Obata
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Rainer Hoefgen
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Alisdair R. Fernie
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Joachim Fisahn
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Blanca San Segundo
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics, Consejo Superior de Investigaciones Científicos, Institute of Agro-food Research and Technology, Autonomus University of Barcelona, University of Barcelona, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
| | - Emmanuel Guiderdoni
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixte de Recherche, Genetic Improvement and Adaptation of Mediterranean and Tropical Plants, 34398 Montpellier, cedex 5, France
| | - Jos H.M. Schippers
- Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
| | - Bernd Mueller-Roeber
- Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
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22
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Morneau DJK, Jaworski AF, Aitken SM. Identification of cystathionine γ-synthase and threonine synthase from Cicer arietinum and Lens culinaris. Biochem Cell Biol 2013; 91:95-101. [PMID: 23527638 DOI: 10.1139/bcb-2012-0096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
In plants, cystathionine γ-synthase (CGS) and threonine synthase (TS) compete for the branch-point metabolite O-phospho-L-homoserine. These enzymes are potential targets for metabolic engineering studies, aiming to alter the flux through the competing methionine and threonine biosynthetic pathways, with the goal of increasing methionine production. Although CGS and TS have been characterized in the model organisms Escherichia coli and Arabidopsis thaliana, little information is available on these enzymes in other, particularly plant, species. The functional CGS and TS coding sequences from the grain legumes Cicer arietinum (chickpea) and Lens culinaris (lentil) identified in this study share approximately 80% amino acid sequence identity with the corresponding sequences from Glycine max. At least 7 active-site residues of grain legume CGS and TS are conserved in the model bacterial enzymes, including the catalytic base. Putative processing sites that remove the targeting sequence and result in functional TS were identified in the target species.
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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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24
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Galili G, Amir R. Fortifying plants with the essential amino acids lysine and methionine to improve nutritional quality. PLANT BIOTECHNOLOGY JOURNAL 2013; 11:211-22. [PMID: 23279001 DOI: 10.1111/pbi.12025] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/27/2012] [Accepted: 10/12/2012] [Indexed: 05/03/2023]
Abstract
Humans, as well as farm animals, cannot synthesize a number of essential amino acids, which are critical for their survival. Hence, these organisms must obtain these essential amino acids from their diets. Cereal and legume crops, which represent the major food and feed sources for humans and livestock worldwide, possess limiting levels of some of these essential amino acids, particularly Lys and Met. Extensive efforts were made to fortify crop plants with these essential amino acids using traditional breeding and mutagenesis. However, aside from some results obtained with maize, none of these approaches was successful. Therefore, additional efforts using genetic engineering approaches concentrated on increasing the synthesis and reducing the catabolism of these essential amino acids and also on the expression of recombinant proteins enriched in them. In the present review, we discuss the basic biological aspects associated with the synthesis and accumulation of these amino acids in plants and also describe recent developments associated with the fortification of crop plants with essential amino acids by genetic engineering approaches.
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Affiliation(s)
- Gad Galili
- Department of Plant Science, The Weizmann Institute of Science, Rehovot, Israel.
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25
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Nguyen HC, Hoefgen R, Hesse H. Improving the nutritive value of rice seeds: elevation of cysteine and methionine contents in rice plants by ectopic expression of a bacterial serine acetyltransferase. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:5991-6001. [PMID: 23048130 DOI: 10.1093/jxb/ers253] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
With the aim of increasing the cysteine level in rice (Oryza sativa L.) and thus improving its nutritional quality, transgenic rice plants were generated expressing an Escherichia coli serine acetyltransferase isoform (EcSAT), the enzyme synthesizing O-acetylserine, the precursor of cysteine. The gene was fused to the transit peptide of the Arabidopsis Rubisco and driven by a ubiquitin promoter to target the enzyme to plastids. Twenty-two transgenic plants were examined for transgene protein expression, and five lines with a high expression level and enzymatic activity, respectively, were selected for further analysis. In these lines, the contents of cysteine and glutathione increased 2.4-fold and 2-fold, respectively. More important is the increase in free methionine and methionine incorporated into the water-soluble protein fraction in seeds. Free methionine increased in leaves up to 2.7-fold, in seeds up to 1.4-fold, and bound to seed proteins up to 4.8-fold, respectively, while the bound methionine level remained constant or even decreased in leaves. Notably, the transgenic lines exhibited higher isoleucine, leucine, and valine contents (each up to 2-fold depending on tissue, free, or bound), indicating a potential conversion of methionine via methionine γ-lyase to isoleucine. As the transgenic rice plants overexpressing EcSAT had significantly higher levels of both soluble and protein-bound methionine, isoleucine, cysteine, and glutathione in rice they may represent a model and target system for improving the nutritional quality of cereal crops.
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Affiliation(s)
- Huu Cuong Nguyen
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
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26
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Liao D, Pajak A, Karcz SR, Chapman BP, Sharpe AG, Austin RS, Datla R, Dhaubhadel S, Marsolais F. Transcripts of sulphur metabolic genes are co-ordinately regulated in developing seeds of common bean lacking phaseolin and major lectins. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:6283-95. [PMID: 23066144 PMCID: PMC3481216 DOI: 10.1093/jxb/ers280] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The lack of phaseolin and phytohaemagglutinin in common bean (dry bean, Phaseolus vulgaris) is associated with an increase in total cysteine and methionine concentrations by 70% and 10%, respectively, mainly at the expense of an abundant non-protein amino acid, S-methyl-cysteine. Transcripts were profiled between two genetically related lines differing for this trait at four stages of seed development using a high density microarray designed for common bean. Transcripts of multiple sulphur-rich proteins were elevated, several previously identified by proteomics, including legumin, basic 7S globulin, albumin-2, defensin, albumin-1, the Bowman-Birk type proteinase inhibitor, the double-headed trypsin inhibitor, and the Kunitz trypsin inhibitor. A co-ordinated regulation of transcripts coding for sulphate transporters, sulphate assimilatory enzymes, serine acetyltransferases, cystathionine β-lyase, homocysteine S-methyltransferase and methionine gamma-lyase was associated with changes in cysteine and methionine concentrations. Differential gene expression of sulphur-rich proteins preceded that of sulphur metabolic enzymes, suggesting a regulation by demand from the protein sink. Up-regulation of SERAT1;1 and -1;2 expression revealed an activation of cytosolic O-acetylserine biosynthesis. Down-regulation of SERAT2;1 suggested that cysteine and S-methyl-cysteine biosynthesis may be spatially separated in different subcellular compartments. Analysis of free amino acid profiles indicated that enhanced cysteine biosynthesis was correlated with a depletion of O-acetylserine. These results contribute to our understanding of the regulation of sulphur metabolism in developing seed in response to a change in the composition of endogenous proteins.
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Affiliation(s)
- Dengqun Liao
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
| | - Agnieszka Pajak
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
| | - Steven R. Karcz
- Agriculture and Agri-Food Canada, Bioproducts and Bioprocesses, Saskatoon Research Centre, 107 Science Place, Saskatoon, Saskatchewan S7N 0X2, Canada
| | - B. Patrick Chapman
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
| | - Andrew G. Sharpe
- National Research Council Canada, Plant Biotechnology Institute, 110 Gymnasium Place, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Ryan S. Austin
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
| | - Raju Datla
- National Research Council Canada, Plant Biotechnology Institute, 110 Gymnasium Place, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Sangeeta Dhaubhadel
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
- Department of Biology, University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Frédéric Marsolais
- Agriculture and Agri-Food Canada, Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, 1391 Sandford St., London, Ontario N5V 4T3, Canada
- Department of Biology, University of Western Ontario, London, Ontario N6A 5B7, Canada
- * To whom correspondence should be addressed. E-mail:
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27
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Dal Cin V, Tieman DM, Tohge T, McQuinn R, de Vos RC, Osorio S, Schmelz EA, Taylor MG, Smits-Kroon MT, Schuurink RC, Haring MA, Giovannoni J, Fernie AR, Klee HJ. Identification of genes in the phenylalanine metabolic pathway by ectopic expression of a MYB transcription factor in tomato fruit. THE PLANT CELL 2011; 23:2738-53. [PMID: 21750236 PMCID: PMC3226207 DOI: 10.1105/tpc.111.086975] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Altering expression of transcription factors can be an effective means to coordinately modulate entire metabolic pathways in plants. It can also provide useful information concerning the identities of genes that constitute metabolic networks. Here, we used ectopic expression of a MYB transcription factor, Petunia hybrida ODORANT1, to alter Phe and phenylpropanoid metabolism in tomato (Solanum lycopersicum) fruits. Despite the importance of Phe and phenylpropanoids to plant and human health, the pathway for Phe synthesis has not been unambiguously determined. Microarray analysis of ripening fruits from transgenic and control plants permitted identification of a suite of coregulated genes involved in synthesis and further metabolism of Phe. The pattern of coregulated gene expression facilitated discovery of the tomato gene encoding prephenate aminotransferase, which converts prephenate to arogenate. The expression and biochemical data establish an arogenate pathway for Phe synthesis in tomato fruits. Metabolic profiling and ¹³C flux analysis of ripe fruits further revealed large increases in the levels of a specific subset of phenylpropanoid compounds. However, while increased levels of these human nutrition-related phenylpropanoids may be desirable, there were no increases in levels of Phe-derived flavor volatiles.
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Affiliation(s)
- Valeriano Dal Cin
- University of Florida, Horticultural Sciences, Gainesville, Florida 32611-0690
| | - Denise M. Tieman
- University of Florida, Horticultural Sciences, Gainesville, Florida 32611-0690
| | - Takayuki Tohge
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14476 Potsdam-Golm, Germany
| | - Ryan McQuinn
- U.S. Department of Agriculture–Agricultural Research Service, Robert W. Holley Center and Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York 14853
| | - Ric C.H. de Vos
- Plant Research International, 6700 AA Wageningen, The Netherlands
- Centre for BioSystems Genomics, 6700 AB Wageningen, The Netherlands
- Netherlands Metabolomics Centre, 2333 CC Leiden, The Netherlands
| | - Sonia Osorio
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14476 Potsdam-Golm, Germany
| | - Eric A. Schmelz
- Center of Medical, Agricultural, and Veterinary Entomology, U.S. Department of Agriculture–Agricultural Research Service, Chemistry Research Unit, Gainesville, FL 32608
| | - Mark G. Taylor
- University of Florida, Horticultural Sciences, Gainesville, Florida 32611-0690
| | - Miriam T. Smits-Kroon
- Centre for BioSystems Genomics, 6700 AB Wageningen, The Netherlands
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098 XH Amsterdam, The Netherlands
| | - Robert C. Schuurink
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098 XH Amsterdam, The Netherlands
| | - Michel A. Haring
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098 XH Amsterdam, The Netherlands
| | - James Giovannoni
- U.S. Department of Agriculture–Agricultural Research Service, Robert W. Holley Center and Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York 14853
| | - Alisdair R. Fernie
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14476 Potsdam-Golm, Germany
| | - Harry J. Klee
- University of Florida, Horticultural Sciences, Gainesville, Florida 32611-0690
- Address correspondence to
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28
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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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29
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Takahashi H, Kopriva S, Giordano M, Saito K, Hell R. Sulfur assimilation in photosynthetic organisms: molecular functions and regulations of transporters and assimilatory enzymes. ANNUAL REVIEW OF PLANT BIOLOGY 2011; 62:157-84. [PMID: 21370978 DOI: 10.1146/annurev-arplant-042110-103921] [Citation(s) in RCA: 462] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Sulfur is required for growth of all organisms and is present in a wide variety of metabolites having distinctive biological functions. Sulfur is cycled in ecosystems in nature where conversion of sulfate to organic sulfur compounds is primarily dependent on sulfate uptake and reduction pathways in photosynthetic organisms and microorganisms. In vascular plant species, transport proteins and enzymes in this pathway are functionally diversified to have distinct biochemical properties in specific cellular and subcellular compartments. Recent findings indicate regulatory processes of sulfate transport and metabolism are tightly connected through several modes of transcriptional and posttranscriptional mechanisms. This review provides up-to-date knowledge in functions and regulations of sulfur assimilation in plants and algae, focusing on sulfate transport systems and metabolic pathways for sulfate reduction and synthesis of downstream metabolites with diverse biological functions.
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30
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Wulff-Zottele C, Gatzke N, Kopka J, Orellana A, Hoefgen R, Fisahn J, Hesse H. Photosynthesis and metabolism interact during acclimation of Arabidopsis thaliana to high irradiance and sulphur depletion. PLANT, CELL & ENVIRONMENT 2010; 33:1974-88. [PMID: 20573050 DOI: 10.1111/j.1365-3040.2010.02199.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Arabidopsis plants were exposed to high light or sulphur depletion alone or in combination for 6 d, and changes of photosynthetic parameters and metabolite abundances were quantified. Photosynthetic electron transport rates (ETRs) of plants exposed to sulphur depletion and high light decreased strongly at day 2 of the acclimation period. After 3 d of treatment, the photosynthetic capacity recovered in plants exposed to the combined stresses, indicating a short recovery time for re-adjustment of photosynthesis. However, at metabolic level, the stress combination had a profound effect on central metabolic pathways such as the tricarboxylic acid (TCA) cycle, glycolysis, pentose phosphate cycle and large parts of amino acid metabolism. Under these conditions, central metabolites, such as sugars and their phosphates, increased, while sulphur-containing compounds were decreased. Further differential responses were found for the stress indicator proline accumulating already at day 1 of the high-light regime, but in combination with sulphur depletion first declined and after a recovery phase reached a delayed elevated level. Other metabolites such as raffinose and putrescine seem to replace proline during the early combinatorial stress response and may act as alternative protectants. Our findings support the notion that plants integrate the selectively sensed stress factors in central metabolism.
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31
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Maloney GS, Kochevenko A, Tieman DM, Tohge T, Krieger U, Zamir D, Taylor MG, Fernie AR, Klee HJ. Characterization of the branched-chain amino acid aminotransferase enzyme family in tomato. PLANT PHYSIOLOGY 2010; 153:925-36. [PMID: 20435740 PMCID: PMC2899903 DOI: 10.1104/pp.110.154922] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Accepted: 04/30/2010] [Indexed: 05/18/2023]
Abstract
Branched-chain amino acids (BCAAs) are synthesized in plants from branched-chain keto acids, but their metabolism is not completely understood. The interface of BCAA metabolism lies with branched-chain aminotransferases (BCAT) that catalyze both the last anabolic step and the first catabolic step. In this study, six BCAT genes from the cultivated tomato (Solanum lycopersicum) were identified and characterized. SlBCAT1, -2, -3, and -4 are expressed in multiple plant tissues, while SlBCAT5 and -6 were undetectable. SlBCAT1 and -2 are located in the mitochondria, SlBCAT3 and -4 are located in chloroplasts, while SlBCAT5 and -6 are located in the cytosol and vacuole, respectively. SlBCAT1, -2, -3, and -4 were able to restore growth of Escherichia coli BCAA auxotrophic cells, but SlBCAT1 and -2 were less effective than SlBCAT3 and -4 in growth restoration. All enzymes were active in the forward (BCAA synthesis) and reverse (branched-chain keto acid synthesis) reactions. SlBCAT3 and -4 exhibited a preference for the forward reaction, while SlBCAT1 and -2 were more active in the reverse reaction. While overexpression of SlBCAT1 or -3 in tomato fruit did not significantly alter amino acid levels, an expression quantitative trait locus on chromosome 3, associated with substantially higher expression of Solanum pennellii BCAT4, did significantly increase BCAA levels. Conversely, antisense-mediated reduction of SlBCAT1 resulted in higher levels of BCAAs. Together, these results support a model in which the mitochondrial SlBCAT1 and -2 function in BCAA catabolism while the chloroplastic SlBCAT3 and -4 function in BCAA synthesis.
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MESH Headings
- Amino Acids, Branched-Chain/biosynthesis
- Amino Acids, Branched-Chain/chemistry
- Biosynthetic Pathways
- Chromatography, High Pressure Liquid
- Cloning, Molecular
- DNA, Complementary/genetics
- Escherichia coli/growth & development
- Gene Expression Profiling
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genetic Complementation Test
- Inbreeding
- Kinetics
- Solanum lycopersicum/enzymology
- Solanum lycopersicum/genetics
- Multigene Family
- Organ Specificity/genetics
- Physical Chromosome Mapping
- Plants, Genetically Modified
- Protein Transport
- Quantitative Trait Loci/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reproducibility of Results
- Sequence Homology, Amino Acid
- Subcellular Fractions/enzymology
- Transaminases/genetics
- Transaminases/metabolism
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32
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Astolfi S, Zuchi S, Hubberten HM, Pinton R, Hoefgen R. Supply of sulphur to S-deficient young barley seedlings restores their capability to cope with iron shortage. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:799-806. [PMID: 20018904 PMCID: PMC2814111 DOI: 10.1093/jxb/erp346] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 11/03/2009] [Accepted: 11/05/2009] [Indexed: 05/19/2023]
Abstract
The effect of the S nutritional status on a plant's capability to cope with Fe shortage was studied in solution cultivation experiments in barley (Hordeum vulgare L. cv. Europa). Barley is a Strategy II plant and responds to Fe deficiency by secretion of chelating compounds, phytosiderophores (PS). All PS are derived from nicotianamine whose precursor is methionine. This suggests that a long-term supply of an inadequate amount of S could reduce a plant's capability to respond to Fe deficiency by limiting the rate of PS biosynthesis. The responses of barley (Hordeum vulgare L. cv. Europa) plants grown for 12 d on Fe-free nutrient solutions (NS) containing 0 or 1.2 mM SO(4)(2-), was examined after 24 h or 48 h from transfer to NS containing 1.2 mM SO(4)(2-). After the supply of S was restored to S-deprived plants, an increase in PS release in root exudates was evident after 24 h of growth in S-sufficient NS and the increment reached values up to 4-fold higher than the control 48 h after S resupply. When S was supplied to S-deficient plants, leaf ATPS (EC 2.7.7.4) and OASTL (EC 4.2.99.8) activities exhibited a progressive recovery. Furthermore, root HvST1 transcript abundance remained high for 48 h following S resupply and a significant increase in the level of root HvYS1 transcripts was also found after only 24 h of S resupply. Data support the idea that the extent to which the plant is able to cope with Fe starvation is strongly associated with its S nutritional status. In particular, our results are indicative that barley plants fully recover their capability to cope with Fe shortage after the supply of S is restored to S-deficient plants.
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Affiliation(s)
- Stefania Astolfi
- Dipartimento di Agrobiologia e Agrochimica, Università della Tuscia, Via S.C. de Lellis snc, I-01100 Viterbo, Italy.
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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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Hugouvieux V, Dutilleul C, Jourdain A, Reynaud F, Lopez V, Bourguignon J. Arabidopsis putative selenium-binding protein1 expression is tightly linked to cellular sulfur demand and can reduce sensitivity to stresses requiring glutathione for tolerance. PLANT PHYSIOLOGY 2009; 151:768-81. [PMID: 19710230 PMCID: PMC2754620 DOI: 10.1104/pp.109.144808] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 08/24/2009] [Indexed: 05/22/2023]
Abstract
Selenium-Binding Protein1 (SBP1) gene expression was studied in Arabidopsis (Arabidopsis thaliana) seedlings challenged with several stresses, including cadmium (Cd), selenium {selenate [Se(VI)] and selenite [Se(IV)]}, copper (Cu), zinc (Zn), and hydrogen peroxide (H(2)O(2)) using transgenic lines expressing the luciferase (LUC) reporter gene under the control of the SBP1 promoter. In roots and shoots of SBP1LUC lines, LUC activity increased in response to Cd, Se(VI), Cu, and H(2)O(2) but not in response to Se(IV) or Zn. The pattern of expression of SBP1 was similar to that of PRH43, which encodes the 5'-Adenylylphosphosulfate Reductase2, a marker for the induction of the sulfur assimilation pathway, suggesting that an enhanced sulfur demand triggers SBP1 up-regulation. Correlated to these results, SBP1 promoter showed enhanced activity in response to sulfur starvation. The sulfur starvation induction of SBP1 was abolished by feeding the plants with glutathione (GSH) and was enhanced when seedlings were treated simultaneously with buthionine sulfoxide, which inhibits GSH synthesis, indicating that GSH level participates in the regulation of SBP1 expression. Changes in total GSH level were observed in seedlings challenged with Cd, Se(VI), and H(2)O(2). Accordingly, cad2-1 seedlings, affected in GSH synthesis, were more sensitive than wild-type plants to these three stresses. Moreover, wild-type and cad2-1 seedlings overexpressing SBP1 showed a significant enhanced tolerance to Se(VI) and H(2)O(2) in addition to the previously described resistance to Cd, highlighting that SBP1 expression decreases sensitivity to stress requiring GSH for tolerance. These results are discussed with regard to the potential regulation and function of SBP1 in plants.
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Affiliation(s)
- Véronique Hugouvieux
- Laboratoire de Physiologie Cellulaire Végétale, UMR 5168, Commissariat à l'Energie Atomique/CNRS/Université Joseph-Fourier/INRA, Institut de Recherches en Technologies et Sciences pour le Vivant, Commissariat à l'Energie Atomique-Grenoble, 38054 Grenoble cedex 9, France.
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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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Krueger S, Niehl A, Lopez Martin MC, Steinhauser D, Donath A, Hildebrandt T, Romero LC, Hoefgen R, Gotor C, Hesse H. Analysis of cytosolic and plastidic serine acetyltransferase mutants and subcellular metabolite distributions suggests interplay of the cellular compartments for cysteine biosynthesis in Arabidopsis. PLANT, CELL & ENVIRONMENT 2009; 32:349-367. [PMID: 19143986 DOI: 10.1111/j.1365-3040.2009.01928.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In plants, the enzymes for cysteine synthesis serine acetyltransferase (SAT) and O-acetylserine-(thiol)-lyase (OASTL) are present in the cytosol, plastids and mitochondria. However, it is still not clearly resolved to what extent the different compartments are involved in cysteine biosynthesis and how compartmentation influences the regulation of this biosynthetic pathway. To address these questions, we analysed Arabidopsis thaliana T-DNA insertion mutants for cytosolic and plastidic SAT isoforms. In addition, the subcellular distribution of enzyme activities and metabolite concentrations implicated in cysteine and glutathione biosynthesis were revealed by non-aqueous fractionation (NAF). We demonstrate that cytosolic SERAT1.1 and plastidic SERAT2.1 do not contribute to cysteine biosynthesis to a major extent, but may function to overcome transport limitations of O-acetylserine (OAS) from mitochondria. Substantiated by predominantly cytosolic cysteine pools, considerable amounts of sulphide and presence of OAS in the cytosol, our results suggest that the cytosol is the principal site for cysteine biosynthesis. Subcellular metabolite analysis further indicated efficient transport of cysteine, gamma-glutamylcysteine and glutathione between the compartments. With respect to regulation of cysteine biosynthesis, estimation of subcellular OAS and sulphide concentrations established that OAS is limiting for cysteine biosynthesis and that SAT is mainly present bound in the cysteine-synthase complex.
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Affiliation(s)
- Stephan Krueger
- Max Planck Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476 Potsdam-Golm, France
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Van Wilder V, De Brouwer V, Loizeau K, Gambonnet B, Albrieux C, Van Der Straeten D, Lambert WE, Douce R, Block MA, Rebeille F, Ravanel S. C1 metabolism and chlorophyll synthesis: the Mg-protoporphyrin IX methyltransferase activity is dependent on the folate status. THE NEW PHYTOLOGIST 2008; 182:137-145. [PMID: 19076298 DOI: 10.1111/j.1469-8137.2008.02707.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
* Tetrahydrofolate derivatives are central cofactors of C1 metabolism. Using methotrexate as a specific inhibitor of folate biosynthesis, we altered the folate status in 10-d-old etiolated pea (Pisum sativum) leaves and followed the rate of chlorophyll synthesis upon illumination. * In our conditions, the folate concentration decreased only from 5.7 to 4.2 nmol g(-1) FW, but the amount of chlorophyll after 24 h of illumination was reduced 2.5 times. Folate status and rate of chlorophyll synthesis were apparently correlated through the methyl cycle. * Indeed, we observed that methyl-tetrahydrofolate was the folate derivative most affected by the treatment; the decrease of methyl-tetrahydrofolate was associated with a sharp rise in homocysteine and S-adenosylhomocysteine concentrations, which are normally maintained at very low values, shifting the methylation index (S-adenosylmethionine/S-adenosylhomocysteine ratio) from 7 to 1; the decrease of the methylation index reduced by a factor of 3 the activity of the Mg-protoporphyrin IX methyltransferase (CHLM), an essential enzyme for chlorophyll synthesis. CHLM gene expression and protein concentration remained unchanged, suggesting that this inhibition relied essentially on metabolic regulation. * These results point out that an even moderate change in the folate status may affect plant development and adaptation.
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Affiliation(s)
- Valérie Van Wilder
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Veerle De Brouwer
- Laboratory of Toxicology, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Karen Loizeau
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Bernadette Gambonnet
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Catherine Albrieux
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Dominique Van Der Straeten
- Unit Plant Hormone Signaling and Bioimaging, Department of Molecular Genetics, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Willy E Lambert
- Laboratory of Toxicology, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Roland Douce
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Maryse A Block
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Fabrice Rebeille
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Stéphane Ravanel
- Laboratoire de Physiologie Cellulaire Végétale, UMR5168 CNRS-CEA-INRA-Université Joseph Fourier Grenoble I, Institut de Recherches en Technologies et Sciences pour le Vivant, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, France
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Schippers JHM, Nunes-Nesi A, Apetrei R, Hille J, Fernie AR, Dijkwel PP. The Arabidopsis onset of leaf death5 mutation of quinolinate synthase affects nicotinamide adenine dinucleotide biosynthesis and causes early ageing. THE PLANT CELL 2008; 20:2909-25. [PMID: 18978034 PMCID: PMC2590718 DOI: 10.1105/tpc.107.056341] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 10/03/2008] [Accepted: 10/15/2008] [Indexed: 05/18/2023]
Abstract
Leaf senescence in Arabidopsis thaliana is a strict, genetically controlled nutrient recovery program, which typically progresses in an age-dependent manner. Leaves of the Arabidopsis onset of leaf death5 (old5) mutant exhibit early developmental senescence. Here, we show that OLD5 encodes quinolinate synthase (QS), a key enzyme in the de novo synthesis of NAD. The Arabidopsis QS was previously shown to carry a Cys desulfurase domain that stimulates reconstitution of the oxygen-sensitive Fe-S cluster that is required for QS activity. The old5 lesion in this enzyme does not affect QS activity but it decreases its Cys desulfurase activity and thereby the long-term catalytic competence of the enzyme. The old5 mutation causes increased NAD steady state levels that coincide with increased activity of enzymes in the NAD salvage pathway. NAD plays a key role in cellular redox reactions, including those of the tricarboxylic acid cycle. Broad-range metabolite profiling of the old5 mutant revealed that it contains higher levels of tricarboxylic acid cycle intermediates and nitrogen-containing amino acids. The mutant displays a higher respiration rate concomitant with increased expression of oxidative stress markers. We postulate that the alteration in the oxidative state is integrated into the plant developmental program, causing early ageing of the mutant.
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Affiliation(s)
- Jos H M Schippers
- Molecular Biology of Plants, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9751 NN Haren, The Netherlands
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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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Dancs G, Kondrák M, Bánfalvi Z. The effects of enhanced methionine synthesis on amino acid and anthocyanin content of potato tubers. BMC PLANT BIOLOGY 2008; 8:65. [PMID: 18549488 PMCID: PMC2438360 DOI: 10.1186/1471-2229-8-65] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Accepted: 06/12/2008] [Indexed: 05/19/2023]
Abstract
BACKGROUND Potato is a staple food in the diet of the world's population and also being used as animal feed. Compared to other crops, however, potato tubers are relatively poor in the essential amino acid, methionine. Our aim was to increase the methionine content of tubers by co-expressing a gene involved in methionine synthesis with a gene encoding a methionine-rich storage protein in potato plants. RESULTS In higher plants, cystathionine gamma-synthase (CgS) is the first enzyme specific to methionine biosynthesis. We attempted to increase the methionine content of tubers by expressing the deleted form of the Arabidopsis CgS (CgSDelta90), which is not regulated by methionine, in potato plants. To increase the incorporation of free methionine into a storage protein the CgSDelta90 was co-transformed with the methionine-rich 15-kD beta-zein. Results demonstrated a 2- to 6-fold increase in the free methionine content and in the methionine content of the zein-containing protein fraction of the transgenic tubers. In addition, in line with higher methionine content, the amounts of soluble isoleucine and serine were also increased. However, all of the lines with high level of CgSDelta90 expression were phenotypically abnormal showing severe growth retardation, changes in leaf architecture and 40- to 60% reduction in tuber yield. Furthermore, the colour of the transgenic tubers was altered due to the reduced amounts of anthocyanin pigments. The mRNA levels of phenylalanine ammonia-lyase (PAL), the enzyme catalysing the first step of anthocyanin synthesis, were decreased. CONCLUSION Ectopic expression of CgSDelta90 increases the methionine content of tubers, however, results in phenotypic aberrations in potato. Co-expression of the 15-kD beta-zein with CgSDelta90 results in elevation of protein-bound methionine content of tubers, but can not overcome the phenotypical changes caused by CgSDelta90 and can not significantly improve the nutritional value of tubers. The level of PAL mRNA and consequently the amount of anthocyanin pigments are reduced in the CgSDelta90 transgenic tubers suggesting that methionine synthesis and production of anthocyanins is linked.
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Affiliation(s)
- Gábor Dancs
- Agricultural Biotechnology Center, P.O. Box 411, H-2101 Gödöllõ, Hungary
| | - Mihály Kondrák
- Agricultural Biotechnology Center, P.O. Box 411, H-2101 Gödöllõ, Hungary
| | - Zsófia Bánfalvi
- Agricultural Biotechnology Center, P.O. Box 411, H-2101 Gödöllõ, Hungary
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Hacham Y, Matityahu I, Schuster G, Amir R. Overexpression of mutated forms of aspartate kinase and cystathionine gamma-synthase in tobacco leaves resulted in the high accumulation of methionine and threonine. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 54:260-71. [PMID: 18208521 DOI: 10.1111/j.1365-313x.2008.03415.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Methionine and threonine are two essential amino acids, the levels of which limit the nutritional quality of plants. Both amino acids diverge from the same branch of the aspartate family biosynthesis pathway; therefore, their biosynthesis pathways compete for the same carbon/amino substrate. To further elucidate the regulation of methionine biosynthesis and seek ways of increasing the levels of these two amino acids, we crossed transgenic tobacco plants overexpressing the bacterial feedback-insensitive aspartate kinase (bAK), containing a significantly higher threonine level, with plants overexpressing Arabidopsis cystathionine gamma-synthase (AtCGS), the first unique enzyme of methionine biosynthesis. Plants co-expressing bAK and the full-length AtCGS (F-AtCGS) have significantly higher methionine and threonine levels compared with the levels found in wild-type plants, but the methionine level does not increase beyond that found in plants expressing F-AtCGS alone. This finding can be explained through the feedback inhibition regulation mediated by the methionine metabolite on the transcript level of AtCGS. To test this assumption, plants expressing bAK were crossed with plants expressing two mutated forms of AtCGS in which the domains responsible for the feedback regulation have been deleted. Indeed, significantly higher methionine contents and its metabolites levels accumulated in the newly produced plants, and the levels of threonine were also significantly higher than in the wild-type plants. The transcript level of the two mutated forms of AtCGS significantly increased when there was a high content of threonine in the plants, suggesting that threonine modulates, probably indirectly, the transcript level of AtCGS.
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Affiliation(s)
- Yael Hacham
- Laboratory of Plant Science, Migal Galilee Technology Center, P.O. Box 831, Kiryat Shmona 12 100, Israel
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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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Falkenberg B, Witt I, Zanor MI, Steinhauser D, Mueller-Roeber B, Hesse H, Hoefgen R. Transcription factors relevant to auxin signalling coordinate broad-spectrum metabolic shifts including sulphur metabolism. JOURNAL OF EXPERIMENTAL BOTANY 2008; 59:2831-46. [PMID: 18596113 PMCID: PMC2486478 DOI: 10.1093/jxb/ern144] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 04/22/2008] [Accepted: 04/28/2008] [Indexed: 05/18/2023]
Abstract
A systems approach has previously been used to follow the response behaviour of Arabidopsis thaliana plants upon sulphur limitation. A response network was reconstructed from a time series of transcript and metabolite profiles, integrating complex metabolic and transcript data in order to investigate a potential causal relationship. The resulting scale-free network allowed potential transcriptional regulators of sulphur metabolism to be identified. Here, three sulphur-starvation responsive transcription factors, IAA13, IAA28, and ARF-2 (ARF1-Binding Protein), all of which are related to auxin signalling, were selected for further investigation. IAA28 overexpressing and knock-down lines showed no major morphological changes, whereas IAA13- and ARF1-BP-overexpressing plants grew more slowly than the wild type. Steady-state metabolite levels and expression of pathway-relevant genes were monitored under normal and sulphate-depleted conditions. For all lines, changes in transcript and metabolite levels were observed, yet none of these changes could exclusively be linked to sulphur stress. Instead, up- or down-regulation of the transcription factors caused metabolic changes which in turn affected sulphur metabolism. Auxin-relevant transcription factors are thus part of a complex response pattern to nutrient starvation that serve as coordinators of the metabolic shifts driving sulphur homeostasis rather then as direct effectors of the sulphate assimilation pathway. This study provides the first evidence ever presented that correlates auxin-related transcriptional regulators with primary plant metabolism.
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Affiliation(s)
- Bettina Falkenberg
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
| | - Isabell Witt
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
| | - Maria Inés Zanor
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
| | - Dirk Steinhauser
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
| | - Bernd Mueller-Roeber
- Universität Potsdam, Institut fuer Biochemie und Biologie, Karl-Liebknecht-Str. 24–25, Haus 20, 14476 Potsdam-Golm, Germany
| | - Holger Hesse
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
- To whom correspondence should be addressed. E-mail:
| | - Rainer Hoefgen
- Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, 14424 Potsdam, Germany
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Metabolism of Methionine in Plants and Phototrophic Bacteria. SULFUR METABOLISM IN PHOTOTROPHIC ORGANISMS 2008. [DOI: 10.1007/978-1-4020-6863-8_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Loizeau K, Gambonnet B, Zhang GF, Curien G, Jabrin S, Van Der Straeten D, Lambert WE, Rébeillé F, Ravanel S. Regulation of one-carbon metabolism in Arabidopsis: the N-terminal regulatory domain of cystathionine gamma-synthase is cleaved in response to folate starvation. PLANT PHYSIOLOGY 2007; 145:491-503. [PMID: 17720756 PMCID: PMC2048731 DOI: 10.1104/pp.107.105379] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In all organisms, control of folate homeostasis is of vital importance to sustain the demand for one-carbon (C1) units that are essential in major metabolic pathways. In this study we induced folate deficiency in Arabidopsis (Arabidopsis thaliana) cells by using two antifolate inhibitors. This treatment triggered a rapid and important decrease in the pool of folates with significant modification in the distribution of C1-substituted folate coenzymes, suggesting an adaptive response to favor a preferential shuttling of the flux of C1 units to the synthesis of nucleotides over the synthesis of methionine (Met). Metabolic profiling of folate-deficient cells indicated important perturbation of the activated methyl cycle because of the impairment of Met synthases that are deprived of their substrate 5-methyl-tetrahydrofolate. Intriguingly, S-adenosyl-Met and Met pools declined during the initial period of folate starvation but were further restored to typical levels. Reestablishment of Met and S-adenosyl-Met homeostasis was concomitant with a previously unknown posttranslational modification that consists in the removal of 92 amino acids at the N terminus of cystathionine gamma-synthase (CGS), the first specific enzyme for Met synthesis. Rescue experiments and analysis of different stresses indicated that CGS processing is specifically associated with perturbation of the folates pool. Also, CGS processing involves chloroplastic serine-type proteases that are expressed in various plant species subjected to folate starvation. We suggest that a metabolic effector, to date unidentified, can modulate CGS activity in vivo through an interaction with the N-terminal domain of the enzyme and that removal of this domain can suppress this regulation.
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Affiliation(s)
- Karen Loizeau
- Laboratoire de Physiologie Cellulaire Végétale, Institut National de la Recherche Agronomique, Université Joseph Fourier Grenoble I, Grenoble, France
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Hacham Y, Song L, Schuster G, Amir R. Lysine enhances methionine content by modulating the expression of S-adenosylmethionine synthase. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 51:850-61. [PMID: 17617175 DOI: 10.1111/j.1365-313x.2007.03184.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Lysine and methionine are two essential amino acids whose levels affect the nutritional quality of cereals and legume plants. Both amino acids are synthesized through the aspartate family biosynthesis pathway. Within this family, lysine and methionine are produced by two different branches, the lysine branch and the threonine-methionine branch, which compete for the same carbon/amino substrate. To elucidate the relationship between these biosynthetic branches, we crossed two lines of transgenic tobacco plants: one that overexpresses the feedback-insensitive bacterial enzyme dihydrodipicolinate synthase (DHPS) and contains a significantly higher level of lysine, and a second that overexpresses Arabidopsis cystathionine gamma-synthase (AtCGS), the first unique enzyme of methionine biosynthesis. Significantly higher levels of methionine and its metabolite, S-methylmethionine (SMM), accumulated in the newly produced plants compared with plants overexpressing AtCGS alone, while the level of lysine remained the same as in those overexpressing DHPS alone. The increased levels of methionine and SMM were correlated with increases in the mRNA and protein levels of AtCGS and a reduced mRNA level for the genes encoding S-adnosylmethionine (SAM) synthase, which converts methionine to SAM. Reduction in SAMS expression level leads most probably to the reduction of SAM found in plants that feed with lysine. As SAM is a negative regulator of CGS, this reduction leads to higher expression of CGS and consequently to an increased level of methionine. Elucidating the relationship between lysine and methionine synthesis may lead to new ways of producing transgenic crop plants containing increased methionine and lysine levels, thus improving their nutritional quality.
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Affiliation(s)
- Yael Hacham
- Laboratory of Plant Science, Migal Galilee Technology Center, Kiryat Shmona, Israel
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Rinder J, Casazza AP, Hoefgen R, Hesse H. Regulation of aspartate-derived amino acid homeostasis in potato plants (Solanum tuberosum L.) by expression of E. coli homoserine kinase. Amino Acids 2007; 34:213-22. [PMID: 17624493 DOI: 10.1007/s00726-007-0504-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Accepted: 02/06/2007] [Indexed: 11/25/2022]
Abstract
The availability of the carbon backbone O-phosphohomoserine (OPHS) is critical to methionine (met) and threonine (thr) synthesis. OPHS derives from homoserine and is formed by homoserine kinase (HSK). To clarify the function of HSK in cellular metabolism, the E. coli HSK ortholog thrB was expressed in potato plants targeting the EcHSK protein to chloroplasts and to the cytosol. Both approaches resulted in up to 11 times increased total HSK enzyme activity. Transgenic plants exhibited reduced homoserine levels while met and thr did not accumulate significantly. However, the precursor cysteine and upstream intermediates of met such as cystathionine and homocysteine did indicating an accelerated carbon flow towards the end products. Coincidently, plants with elevated cytosolic levels of EcHSK exhibited a reduction in transcript levels of the endogenous HSK, as well as of threonine synthase (TS), cystathionine beta-lyase (CbL), and met synthase (MS). In all plants, cystathionine gamma-synthase (CgS) expression remained relatively unchanged from wild type levels, while S-adenosylmethionine synthetase (SAMS) expression increased. Feeding studies with externally supplied homoserine fostered the synthesis of met and thr but the regulation of synthesis of both amino acids retained the wild type regulation pattern. The results indicate that excess of plastidial localised HSK activity does not influence the de novo synthesis of met and thr. However, expression of HSK in the cytosol resulted in the down-regulation of gene expression of pathway genes probably mediated via OPHS. We integrated these data in a novel working model describing the regulatory mechanism of met and thr homeostasis.
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Affiliation(s)
- J Rinder
- Department of Molecular Physiology, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Golm, Germany
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Liang Y, Chen H, Tang M, Shen S. Proteome analysis of an ectomycorrhizal fungus Boletus edulis under salt shock. ACTA ACUST UNITED AC 2007; 111:939-46. [PMID: 17716885 DOI: 10.1016/j.mycres.2007.06.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 05/25/2007] [Accepted: 06/10/2007] [Indexed: 11/25/2022]
Abstract
Soil salinization has become a severe global problem and salinity is one of the most severe abiotic stresses inhibiting growth and survival of mycorrhizal fungi and their host plants. Salinity tolerance of ectomycorrhizal fungi and survival of ectomycorrhizal inocula is essential to reforestation and ecosystem restoration in saline areas. Proteomic changes of an ectomycorrhizal fungus, Boletus edulis, when exposed to salt stress conditions (4% NaCl, w/v) were determined using two-dimensional electrophoresis (2DE) and mass spectrometry (MS) techniques. Twenty-two protein spots, 14 upregulated and 8 downregulated, were found changed under salt stress conditions. Sixteen changed protein spots were identified by nanospray ESI Q-TOF MS/MS and liquid chromatography MS/MS. These proteins were involved in biosynthesis of methionine and S-adenosylmethionine, glycolysis, DNA repair, cell cycle control, and general stress tolerance, and their possible functions in salinity adaptation of Boletus edulis were discussed.
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Affiliation(s)
- Yu Liang
- Key laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China.
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Beauregard M, Hefford MA. Enhancement of essential amino acid contents in crops by genetic engineering and protein design. PLANT BIOTECHNOLOGY JOURNAL 2006; 4:561-74. [PMID: 17309730 DOI: 10.1111/j.1467-7652.2006.00204.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The importance and urgency of providing humans and animals with quality proteins are reflected in the growing scientific and industrial interest in augmenting the nutritive value of the world's protein sources. Such nutritive value is determined by the protein content in 'essential amino acids', those that cannot be synthesized de novo and that must be supplied from the diet. It is the object of this review to discuss recent advances in the genetic modification of crops that aim to provide enhanced quantities of essential amino acids.
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Affiliation(s)
- Marc Beauregard
- Plant Biology Group, Département de Chimie-Biologie, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada, G9A 5H7.
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