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Ovchinnikova E, Chiasson D, Wen Z, Wu Y, Tahaei H, Smith PMC, Perrine-Walker F, Kaiser BN. Arbuscular-Mycorrhizal Symbiosis in Medicago Regulated by the Transcription Factor MtbHLHm1;1 and the Ammonium Facilitator Protein MtAMF1;3. Int J Mol Sci 2023; 24:14263. [PMID: 37762569 PMCID: PMC10532333 DOI: 10.3390/ijms241814263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/10/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Root systems of most land plants are colonised by arbuscular mycorrhiza fungi. The symbiosis supports nutrient acquisition strategies predominantly associated with plant access to inorganic phosphate. The nutrient acquisition is enhanced through an extensive network of external fungal hyphae that extends out into the soil, together with the development of fungal structures forming specialised interfaces with root cortical cells. Orthologs of the bHLHm1;1 transcription factor, previously described in soybean nodules (GmbHLHm1) and linked to the ammonium facilitator protein GmAMF1;3, have been identified in Medicago (Medicago truncatula) roots colonised by AM fungi. Expression studies indicate that transcripts of both genes are also present in arbuscular containing root cortical cells and that the MtbHLHm1;1 shows affinity to the promoter of MtAMF1;3. Both genes are induced by AM colonisation. Loss of Mtbhlhm1;1 expression disrupts AM arbuscule abundance and the expression of the ammonium transporter MtAMF1;3. Disruption of Mtamf1;3 expression reduces both AM colonisation and arbuscule development. The respective activities of MtbHLHm1;1 and MtAMF1;3 highlight the conservation of putative ammonium regulators supporting both the rhizobial and AM fungal symbiosis in legumes.
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Affiliation(s)
- Evgenia Ovchinnikova
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW 2570, Australia
| | - David Chiasson
- Department of Biology, Saint Mary’s University, Halifax, NS B3H 3C3, Canada
| | - Zhengyu Wen
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW 2570, Australia
| | - Yue Wu
- School of Agriculture, Food and Wine, Waite Campus, University of Adelaide, Urrbrae, SA 5005, Australia
| | - Hero Tahaei
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW 2570, Australia
| | - Penelope M. C. Smith
- Agribio, Centre for AgriBiosciences, La Trobe University, 5 Ring Road, Bundoora, VIC 3083, Australia
| | - Francine Perrine-Walker
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW 2570, Australia
| | - Brent N. Kaiser
- Sydney Institute of Agriculture, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW 2570, Australia
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2
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Gupta SVK, Smith PMC, Natera SHA, Roessner U. Biochemical Changes in Two Barley Genotypes Inoculated With a Beneficial Fungus Trichoderma harzianum Rifai T-22 Grown in Saline Soil. Front Plant Sci 2022; 13:908853. [PMID: 35982702 PMCID: PMC9379338 DOI: 10.3389/fpls.2022.908853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
One of the most important environmental factors impacting crop plant productivity is soil salinity. Fungal endophytes have been characterised as biocontrol agents that help in plant productivity and induce resistance responses to several abiotic stresses, including salinity. In the salt-tolerant cereal crop barley (Hordeum vulgare L.), there is limited information about the metabolites and lipids that change in response to inoculation with fungal endophytes in saline conditions. In this study, gas chromatography coupled to mass spectrometry (GC-MS) and LC-electrospray ionisation (ESI)-quadrupole-quadrupole time of flight (QqTOF)-MS were used to determine the metabolite and lipid changes in two fungal inoculated barley genotypes with differing tolerance levels to saline conditions. The more salt-tolerant cultivar was Vlamingh and less salt tolerant was Gairdner. Trichoderma harzianum strain T-22 was used to treat these plants grown in soil under control and saline (200 mM NaCl) conditions. For both genotypes, fungus-colonised plants exposed to NaCl had greater root and shoot biomass, and better chlorophyll content than non-colonised plants, with colonised-Vlamingh performing better than uninoculated control plants. The metabolome dataset using GC-MS consisted of a total of 93 metabolites of which 74 were identified in roots of both barley genotypes as organic acids, sugars, sugar acids, sugar alcohols, amino acids, amines, and a small number of fatty acids. LC-QqTOF-MS analysis resulted in the detection of 186 lipid molecular species, classified into three major lipid classes-glycerophospholipids, glycerolipids, and sphingolipids, from roots of both genotypes. In Cultivar Vlamingh both metabolites and lipids increased with fungus and salt treatment while in Gairdner they decreased. The results from this study suggest that the metabolic pathways by which the fungus imparts salt tolerance is different for the different genotypes.
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Affiliation(s)
| | | | - Siria H. A. Natera
- Metabolomics Australia, The University of Melbourne, Parkville, VIC, Australia
| | - Ute Roessner
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
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3
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Booth NJ, Smith PMC, Ramesh SA, Day DA. Malate Transport and Metabolism in Nitrogen-Fixing Legume Nodules. Molecules 2021; 26:6876. [PMID: 34833968 PMCID: PMC8618214 DOI: 10.3390/molecules26226876] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/22/2022] Open
Abstract
Legumes form a symbiosis with rhizobia, a soil bacterium that allows them to access atmospheric nitrogen and deliver it to the plant for growth. Biological nitrogen fixation occurs in specialized organs, termed nodules, that develop on the legume root system and house nitrogen-fixing rhizobial bacteroids in organelle-like structures termed symbiosomes. The process is highly energetic and there is a large demand for carbon by the bacteroids. This carbon is supplied to the nodule as sucrose, which is broken down in nodule cells to organic acids, principally malate, that can then be assimilated by bacteroids. Sucrose may move through apoplastic and/or symplastic routes to the uninfected cells of the nodule or be directly metabolised at the site of import within the vascular parenchyma cells. Malate must be transported to the infected cells and then across the symbiosome membrane, where it is taken up by bacteroids through a well-characterized dct system. The dicarboxylate transporters on the infected cell and symbiosome membranes have been functionally characterized but remain unidentified. Proteomic and transcriptomic studies have revealed numerous candidates, but more work is required to characterize their function and localise the proteins in planta. GABA, which is present at high concentrations in nodules, may play a regulatory role, but this remains to be explored.
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Affiliation(s)
- Nicholas J. Booth
- College of Science & Engineering, Flinders University, GPO Box 5100, Adelaide, SA 5001, Australia; (N.J.B.); (S.A.R.)
| | | | - Sunita A. Ramesh
- College of Science & Engineering, Flinders University, GPO Box 5100, Adelaide, SA 5001, Australia; (N.J.B.); (S.A.R.)
| | - David A. Day
- College of Science & Engineering, Flinders University, GPO Box 5100, Adelaide, SA 5001, Australia; (N.J.B.); (S.A.R.)
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Gupta S, Smith PMC, Boughton BA, Rupasinghe TWT, Natera SHA, Roessner U. Inoculation of barley with Trichoderma harzianum T-22 modifies lipids and metabolites to improve salt tolerance. J Exp Bot 2021; 72:7229-7246. [PMID: 34279634 DOI: 10.1093/jxb/erab335] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/17/2021] [Indexed: 05/23/2023]
Abstract
Soil salinity has a serious impact on plant growth and agricultural yield. Inoculation of crop plants with fungal endophytes is a cost-effective way to improve salt tolerance. We used metabolomics to study how Trichoderma harzianum T-22 alleviates NaCl-induced stress in two barley (Hordeum vulgare L.) cultivars, Gairdner and Vlamingh, with contrasting salinity tolerance. GC-MS was used to analyse polar metabolites and LC-MS to analyse lipids in roots during the early stages of interaction with Trichoderma. Inoculation reversed the severe effects of salt on root length in sensitive cv. Gairdner and, to a lesser extent, improved root growth in more tolerance cv. Vlamingh. Biochemical changes showed a similar pattern in inoculated roots after salt treatment. Sugars increased in both cultivars, with ribulose, ribose, and rhamnose specifically increased by inoculation. Salt stress caused large changes in lipids in roots but inoculation with fungus greatly reduced the extent of these changes. Many of the metabolic changes in inoculated cv. Gairdner after salt treatment mirror the response of uninoculated cv. Vlamingh, but there are some metabolites that changed in both cultivars only after fungal inoculation. Further study is required to determine how these metabolic changes are induced by fungal inoculation.
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Affiliation(s)
- Sneha Gupta
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
| | - Penelope M C Smith
- School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia
| | - Berin A Boughton
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
- Australian National Phenome Centre, Murdoch University, Murdoch, Western Australia, Australia
| | - Thusitha W T Rupasinghe
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
- SCIEX, Mulgrave, Victoria, Australia
| | - Siria H A Natera
- Metabolomics Australia, The University of Melbourne, Parkville, Victoria, Australia
| | - Ute Roessner
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
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Schillaci M, Kehelpannala C, Martinez-Seidel F, Smith PMC, Arsova B, Watt M, Roessner U. The Metabolic Response of Brachypodium Roots to the Interaction with Beneficial Bacteria Is Affected by the Plant Nutritional Status. Metabolites 2021; 11:metabo11060358. [PMID: 34205012 PMCID: PMC8228974 DOI: 10.3390/metabo11060358] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/20/2021] [Accepted: 05/31/2021] [Indexed: 11/16/2022] Open
Abstract
The potential of plant growth promoting (PGP) bacteria in improving the performance of plants in suboptimal environments is increasingly acknowledged, but little information is available on the mechanisms underlying this interaction, particularly when plants are subjected to a combination of stresses. In this study, we investigated the effects of the inoculation with the PGP bacteria Azospirillum brasilense (Azospirillum) on the metabolism of the model cereal Brachypodium distachyon (Brachypodium) grown at low temperatures and supplied with insufficient phosphorus. Investigating polar metabolite and lipid fluctuations during early plant development, we found that the bacteria initially elicited a defense response in Brachypodium roots, while at later stages Azospirillum reduced the stress caused by phosphorus deficiency and improved root development of inoculated plants, particularly by stimulating the growth of branch roots. We propose that the interaction of the plant with Azospirillum was influenced by its nutritional status: bacteria were sensed as pathogens while plants were still phosphorus sufficient, but the interaction became increasingly beneficial for the plants as their phosphorus levels decreased. Our results provide new insights on the dynamics of the cereal-PGP bacteria interaction, and contribute to our understanding of the role of beneficial microorganisms in the growth of cereal crops in suboptimal environments.
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Affiliation(s)
- Martino Schillaci
- School of BioSciences, University of Melbourne, Parkville 3010, Australia; (C.K.); (M.W.); (U.R.)
- Correspondence:
| | - Cheka Kehelpannala
- School of BioSciences, University of Melbourne, Parkville 3010, Australia; (C.K.); (M.W.); (U.R.)
| | - Federico Martinez-Seidel
- School of BioSciences, University of Melbourne, Parkville 3010, Australia; (C.K.); (M.W.); (U.R.)
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany;
| | - Penelope M. C. Smith
- Department of Animal, Plant, and Soil Sciences, School of Life Sciences, La Trobe University, Bundoora 3086, Australia;
| | - Borjana Arsova
- Institute for Bio & Geosciences, Plant Sciences (IBG-2), Forschungszentrum Juelich GmbH, 52425 Juelich, Germany;
| | - Michelle Watt
- School of BioSciences, University of Melbourne, Parkville 3010, Australia; (C.K.); (M.W.); (U.R.)
| | - Ute Roessner
- School of BioSciences, University of Melbourne, Parkville 3010, Australia; (C.K.); (M.W.); (U.R.)
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Castro-Rodríguez R, Escudero V, Reguera M, Gil-Díez P, Quintana J, Prieto RI, Kumar RK, Brear E, Grillet L, Wen J, Mysore KS, Walker EL, Smith PMC, Imperial J, González-Guerrero M. Medicago truncatula Yellow Stripe-Like7 encodes a peptide transporter participating in symbiotic nitrogen fixation. Plant Cell Environ 2021. [PMID: 33797764 DOI: 10.1101/2020.03.26.009159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Yellow Stripe-Like (YSL) proteins are a family of plant transporters that are typically involved in transition metal homeostasis. Three of the four YSL clades (I, II and IV) transport metals complexed with the non-proteinogenic amino acid nicotianamine or its derivatives. No such capability has been shown for any member of clade III, but the link between these YSLs and metal homeostasis could be masked by functional redundancy. We studied the role of the clade III YSL protein MtSYL7 in Medicago truncatula nodules. MtYSL7, which encodes a plasma membrane-bound protein, is mainly expressed in the pericycle and cortex cells of the root nodules. Yeast complementation assays revealed that MtSYL7 can transport short peptides. M. truncatula transposon insertion mutants with decreased expression of MtYSL7 had lower nitrogen fixation rates and showed reduced plant growth whether grown in symbiosis with rhizobia or not. YSL7 mutants accumulated more copper and iron in the nodules, which is likely to result from the increased expression of iron uptake and delivery genes in roots. Taken together, these data suggest that MtYSL7 plays an important role in the transition metal homeostasis of nodules and symbiotic nitrogen fixation.
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Affiliation(s)
- Rosario Castro-Rodríguez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Viviana Escudero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - María Reguera
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Patricia Gil-Díez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Julia Quintana
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Rosa Isabel Prieto
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Rakesh K Kumar
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Ella Brear
- Department of Animal, Plant, and Soil Sciences, La Trobe University, Bundoora, Australia
| | - Louis Grillet
- Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan
| | - Jiangqi Wen
- Noble Research Institute, LLC., Ardmore, Oklahoma, USA
| | | | - Elsbeth L Walker
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Penelope M C Smith
- Department of Animal, Plant, and Soil Sciences, La Trobe University, Bundoora, Australia
| | - Juan Imperial
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
- Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain
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7
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Castro-Rodríguez R, Escudero V, Reguera M, Gil-Díez P, Quintana J, Prieto RI, Kumar RK, Brear E, Grillet L, Wen J, Mysore KS, Walker EL, Smith PMC, Imperial J, González-Guerrero M. Medicago truncatula Yellow Stripe-Like7 encodes a peptide transporter participating in symbiotic nitrogen fixation. Plant Cell Environ 2021; 44:1908-1920. [PMID: 33797764 DOI: 10.1111/pce.14059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 03/26/2021] [Accepted: 03/27/2021] [Indexed: 06/12/2023]
Abstract
Yellow Stripe-Like (YSL) proteins are a family of plant transporters that are typically involved in transition metal homeostasis. Three of the four YSL clades (I, II and IV) transport metals complexed with the non-proteinogenic amino acid nicotianamine or its derivatives. No such capability has been shown for any member of clade III, but the link between these YSLs and metal homeostasis could be masked by functional redundancy. We studied the role of the clade III YSL protein MtSYL7 in Medicago truncatula nodules. MtYSL7, which encodes a plasma membrane-bound protein, is mainly expressed in the pericycle and cortex cells of the root nodules. Yeast complementation assays revealed that MtSYL7 can transport short peptides. M. truncatula transposon insertion mutants with decreased expression of MtYSL7 had lower nitrogen fixation rates and showed reduced plant growth whether grown in symbiosis with rhizobia or not. YSL7 mutants accumulated more copper and iron in the nodules, which is likely to result from the increased expression of iron uptake and delivery genes in roots. Taken together, these data suggest that MtYSL7 plays an important role in the transition metal homeostasis of nodules and symbiotic nitrogen fixation.
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Affiliation(s)
- Rosario Castro-Rodríguez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Viviana Escudero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - María Reguera
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Patricia Gil-Díez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Julia Quintana
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Rosa Isabel Prieto
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
| | - Rakesh K Kumar
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Ella Brear
- Department of Animal, Plant, and Soil Sciences, La Trobe University, Bundoora, Australia
| | - Louis Grillet
- Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan
| | - Jiangqi Wen
- Noble Research Institute, LLC., Ardmore, Oklahoma, USA
| | | | - Elsbeth L Walker
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Penelope M C Smith
- Department of Animal, Plant, and Soil Sciences, La Trobe University, Bundoora, Australia
| | - Juan Imperial
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Madrid, Spain
- Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain
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Abstract
Iron is an essential nutrient for the legume-rhizobia symbiosis and nitrogen-fixing bacteroids within root nodules of legumes have a very high demand for the metal. Within the infected cells of nodules, the bacteroids are surrounded by a plant membrane to form an organelle-like structure called the symbiosome. In this review, we focus on how iron is transported across the symbiosome membrane and accessed by the bacteroids.
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Affiliation(s)
- David A. Day
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
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Brear EM, Bedon F, Gavrin A, Kryvoruchko IS, Torres-Jerez I, Udvardi MK, Day DA, Smith PMC. GmVTL1a is an iron transporter on the symbiosome membrane of soybean with an important role in nitrogen fixation. New Phytol 2020; 228:667-681. [PMID: 32533710 DOI: 10.1111/nph.16734] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/27/2020] [Indexed: 05/07/2023]
Abstract
Legumes establish symbiotic relationships with soil bacteria (rhizobia), housed in nodules on roots. The plant supplies carbon substrates and other nutrients to the bacteria in exchange for fixed nitrogen. The exchange occurs across a plant-derived symbiosome membrane (SM), which encloses rhizobia to form a symbiosome. Iron supplied by the plant is crucial for rhizobial enzyme nitrogenase that catalyses nitrogen fixation, but the SM iron transporter has not been identified. We use yeast complementation, real-time PCR and proteomics to study putative soybean (Glycine max) iron transporters GmVTL1a and GmVTL1b and have characterized the role of GmVTL1a using complementation in plant mutants, hairy root transformation and microscopy. GmVTL1a and GmVTL1b are members of the vacuolar iron transporter family and homologous to Lotus japonicus SEN1 (LjSEN1), which is essential for nitrogen fixation. GmVTL1a expression is enhanced in nodule infected cells and both proteins are localized to the SM. GmVTL1a transports iron in yeast and restores nitrogen fixation when expressed in the Ljsen1 mutant. Three GmVTL1a amino acid substitutions that block nitrogen fixation in Ljsen1 plants reduce iron transport in yeast. We conclude GmVTL1a is responsible for transport of iron across the SM to bacteroids and plays a crucial role in the nitrogen-fixing symbiosis.
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Affiliation(s)
- Ella M Brear
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Frank Bedon
- Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Bundoora, VIC, 3083, Australia
| | - Aleksandr Gavrin
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW, 2006, Australia
- Sainsbury Laboratory, University of Cambridge, Cambridge, CB2 1LR, UK
| | - Igor S Kryvoruchko
- Noble Research Institute, Ardmore, OK, 73401, USA
- Molecular Biology and Genetics, Boğaziçi University, Istanbul, Turkey
| | | | | | - David A Day
- College of Science and Engineering, Flinders University, Bedford Park, Adelaide, SA, 5042, Australia
| | - Penelope M C Smith
- Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Bundoora, VIC, 3083, Australia
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10
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Jimenez-Lopez JC, Singh KB, Clemente A, Nelson MN, Ochatt S, Smith PMC. Editorial: Legumes for Global Food Security. Front Plant Sci 2020; 11:926. [PMID: 32733508 PMCID: PMC7359862 DOI: 10.3389/fpls.2020.00926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 06/05/2020] [Indexed: 05/30/2023]
Affiliation(s)
- Jose C. Jimenez-Lopez
- Department of Biochemistry, Cell & Molecular Biology of Plants, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Granada, Spain
| | - Karam B. Singh
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organization (CSIRO), Perth, WA, Australia
| | - Alfonso Clemente
- Department of Physiology and Biochemistry of Animal Nutrition, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Granada, Spain
| | - Matthew N. Nelson
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organization (CSIRO), Perth, WA, Australia
| | - Sergio Ochatt
- Agroécologie, AgroSup Dijon, INRAE, Université de Bourgogne, Dijon, France
| | - Penelope M. C. Smith
- Legumes for Sustainable Agriculture, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
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11
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Sweetman C, Waterman CD, Rainbird BM, Smith PMC, Jenkins CD, Day DA, Soole KL. AtNDB2 Is the Main External NADH Dehydrogenase in Mitochondria and Is Important for Tolerance to Environmental Stress. Plant Physiol 2019; 181:774-788. [PMID: 31409698 PMCID: PMC6776847 DOI: 10.1104/pp.19.00877] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 07/23/2019] [Indexed: 05/02/2023]
Abstract
In addition to the classical electron transport pathway coupled to ATP synthesis, plant mitochondria have an alternative pathway that involves type II NAD(P)H dehydrogenases (NDs) and alternative oxidase (AOX). This alternative pathway participates in thermogenesis in select organs of some species and is thought to help prevent cellular damage during exposure to environmental stress. Here, we investigated the function and role of one alternative path component, AtNDB2, using a transgenic approach in Arabidopsis (Arabidopsis thaliana). Disruption of AtNDB2 expression via T-DNA insertion led to a 90% decrease of external NADH oxidation in isolated mitochondria. Overexpression of AtNDB2 led to increased AtNDB2 protein abundance in mitochondria but did not enhance external NADH oxidation significantly unless AtAOX1A was concomitantly overexpressed and activated, demonstrating a functional link between these enzymes. Plants lacking either AtAOX1A or AtNDB2 were more sensitive to combined drought and elevated light treatments, whereas plants overexpressing these components showed increased tolerance and capacity for poststress recovery. We conclude that AtNDB2 is the predominant external NADH dehydrogenase in mitochondria and together with AtAOX1A forms a complete, functional, nonphosphorylating pathway of electron transport, whose operation enhances tolerance to environmental stress. This study demonstrates that at least one of the alternative NDs, as well as AOX, are important for the stress response.
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Affiliation(s)
- Crystal Sweetman
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
| | - Christopher D Waterman
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
| | - Barry M Rainbird
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
| | - Penelope M C Smith
- Department of Animal, Plant, and Soil Sciences, School of Life Sciences, Latrobe University, Bundoora, Victoria 3083, Australia
| | - Colin D Jenkins
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
| | - David A Day
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
| | - Kathleen L Soole
- College of Science and Engineering, Flinders University of South Australia, Adelaide, South Australia 5042, Australia
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12
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Gupta S, Rupasinghe T, Callahan DL, Natera SHA, Smith PMC, Hill CB, Roessner U, Boughton BA. Spatio-Temporal Metabolite and Elemental Profiling of Salt Stressed Barley Seeds During Initial Stages of Germination by MALDI-MSI and µ-XRF Spectrometry. Front Plant Sci 2019; 10:1139. [PMID: 31608088 PMCID: PMC6774343 DOI: 10.3389/fpls.2019.01139] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 08/21/2019] [Indexed: 05/05/2023]
Abstract
Seed germination is the essential first step in crop establishment, and can be severely affected by salinity stress which can inhibit essential metabolic processes during the germination process. Salt stress during seed germination can trigger lipid-dependent signalling cascades that activate plant adaptation processes, lead to changes in membrane fluidity to help resist the stress, and cause secondary metabolite responses due to increased oxidative stress. In germinating barley (Hordeum vulgare), knowledge of the changes in spatial distribution of lipids and other small molecules at a cellular level in response to salt stress is limited. In this study, mass spectrometry imaging (MSI), liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS), inductively coupled plasma mass spectrometry (ICP-MS), and X-ray fluorescence (XRF) were used to determine the spatial distribution of metabolites, lipids and a range of elements, such as K+ and Na+, in seeds of two barley genotypes with contrasting germination phenology (Australian barley varieties Mundah and Keel). We detected and tentatively identified more than 200 lipid species belonging to seven major lipid classes (fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, prenol lipids, sterol lipids, and polyketides) that differed in their spatial distribution based on genotype (Mundah or Keel), time post-imbibition (0 to 72 h), or treatment (control or salt). We found a tentative flavonoid was discriminant in post-imbibed Mundah embryos under saline conditions, and a delayed flavonoid response in Keel relative to Mundah. We further employed MSI-MS/MS and LC-QToF-MS/MS to explore the identity of the discriminant flavonoid and study the temporal pattern in five additional barley genotypes. ICP-MS was used to quantify the elemental composition of both Mundah and Keel seeds, showing a significant increase in Na+ in salt treated samples. Spatial mapping of elements using µ-XRF localized the elements within the seeds. This study integrates data obtained from three mass spectrometry platforms together with µ-XRF to yield information on the localization of lipids, metabolites and elements improving our understanding of the germination process under salt stress at a molecular level.
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Affiliation(s)
- Sneha Gupta
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Thusitha Rupasinghe
- Metabolomics Australia, School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Damien L. Callahan
- School of Life and Environmental Sciences, Deakin University, Burwood, VIC, Australia
| | - Siria H. A. Natera
- Metabolomics Australia, School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Penelope M. C. Smith
- AgriBio, Centre for AgriBiosciences, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Bundoora, VIC, Australia
| | - Camilla B. Hill
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Ute Roessner
- Metabolomics Australia, School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Berin A. Boughton
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
- Metabolomics Australia, School of BioSciences, University of Melbourne, Parkville, VIC, Australia
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Huen AK, Rodriguez-Medina C, Ho AYY, Atkins CA, Smith PMC. Long-distance movement of phosphate starvation-responsive microRNAs in Arabidopsis. Plant Biol (Stuttg) 2017; 19:643-649. [PMID: 28322489 DOI: 10.1111/plb.12568] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 03/16/2017] [Indexed: 05/07/2023]
Abstract
Plant microRNAs are small RNAs that are important for genetic regulation of processes such as plant development or environmental responses. Specific microRNAs accumulate in the phloem during phosphate starvation, and may act as long-distance signalling molecules. We performed quantitative PCR on Arabidopsis hypocotyl micrograft tissues of wild-type and hen1-6 mutants to assess the mobility of several phosphate starvation-responsive microRNA species. In addition to the previously confirmed mobile species miR399d, the corresponding microRNA* (miR399d*) was identified for the first time as mobile between shoots and roots. Translocation by phosphate-responsive microRNAs miR827 and miR2111a between shoots and roots during phosphate starvation was evident, while their respective microRNA*s were not mobile. The results suggest that long-distance mobility of microRNA species is selective and can occur without the corresponding duplex strand. Movement of miR399d* and root-localised accumulation of miR2111a* opens the potential for persisting microRNA*s to be mobile and functional in novel pathways during phosphate starvation responses.
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Affiliation(s)
- A K Huen
- Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
| | - C Rodriguez-Medina
- The Colombian Agricultural Research Corporation (Corpoica), Palmira, Valle del Cauca, Columbia
| | - A Y Y Ho
- Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
| | - C A Atkins
- Centre for Plant Genetics and Breeding, The University of Western Australia, Crawley, Perth, WA, Australia
| | - P M C Smith
- Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
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14
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Liu DYT, Smith PMC, Barton DA, Day DA, Overall RL. Characterisation of Arabidopsis calnexin 1 and calnexin 2 in the endoplasmic reticulum and at plasmodesmata. Protoplasma 2017; 254:125-136. [PMID: 26680228 DOI: 10.1007/s00709-015-0921-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 12/01/2015] [Indexed: 05/06/2023]
Abstract
Calnexin (CNX) is a highly conserved endoplasmic reticulum (ER) chaperone protein. Both calnexin and the homologous ER-lumenal protein, calreticulin, bind calcium ions and participate in protein folding. There are two calnexins in Arabidopsis thaliana, CNX1 and CNX2. GUS expression demonstrated that these are expressed in most Arabidopsis tissues throughout development. Calnexin transfer DNA (T-DNA) mutant lines exhibited increased transcript abundances of a number of other ER chaperones, including calreticulins, suggesting a degree of redundancy. CNX1 and CNX2 localised to the ER membrane including that within plasmodesmata, the intercellular channels connecting plant cells. This is comparable with the previous localisations of calreticulin in the ER lumen and at plasmodesmata. However, from green fluorescent protein (GFP) diffusion studies in single and double T-DNA insertion mutant lines, as well as overexpression lines, we found no evidence that CNX1 or CNX2 play a role in intercellular transport through plasmodesmata. In addition, calnexin T-DNA mutant lines showed no change in transcript abundance of a number of plasmodesmata-related proteins. CNX1 and CNX2 do not appear to have a specific localisation or function at plasmodesmata-rather the association of calnexin with the ER is simply maintained as the ER passes through plasmodesmata.
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Affiliation(s)
- Danny Y T Liu
- School of Biological Sciences, University of Sydney, Macleay Building A12, Sydney, NSW, 2006, Australia
- Learning and Teaching Centre, Macquarie University, Building C3B 417, Sydney, NSW, 2109, Australia
| | - Penelope M C Smith
- School of Biological Sciences, University of Sydney, Macleay Building A12, Sydney, NSW, 2006, Australia
| | - Deborah A Barton
- School of Biological Sciences, University of Sydney, Macleay Building A12, Sydney, NSW, 2006, Australia
| | - David A Day
- School of Biological Sciences, University of Sydney, Macleay Building A12, Sydney, NSW, 2006, Australia
- School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, SA, 5001, Australia
| | - Robyn L Overall
- School of Biological Sciences, University of Sydney, Macleay Building A12, Sydney, NSW, 2006, Australia.
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15
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Loughlin PC, Duxbury Z, Mugerwa TTM, Smith PMC, Willows RD, Chen M. Spectral properties of bacteriophytochrome AM1_5894 in the chlorophyll d-containing cyanobacterium Acaryochloris marina. Sci Rep 2016; 6:27547. [PMID: 27282102 PMCID: PMC4901347 DOI: 10.1038/srep27547] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/20/2016] [Indexed: 12/12/2022] Open
Abstract
Acaryochloris marina, a unicellular oxygenic photosynthetic cyanobacterium, has uniquely adapted to far-red light-enriched environments using red-shifted chlorophyll d. To understand red-light use in Acaryochloris, the genome of this cyanobacterium was searched for red/far-red light photoreceptors from the phytochrome family, resulting in identification of a putative bacteriophytochrome AM1_5894. AM1_5894 contains three standard domains of photosensory components as well as a putative C-terminal signal transduction component consisting of a histidine kinase and receiver domain. The photosensory domains of AM1_5894 autocatalytically assemble with biliverdin in a covalent fashion. This assembled AM1_5894 shows the typical photoreversible conversion of bacterial phytochromes with a ground-state red-light absorbing (Pr) form with λBV max[Pr] 705 nm, and a red-light inducible far-red light absorbing (Pfr) form with λBV max[Pfr] 758 nm. Surprisingly, AM1_5894 also autocatalytically assembles with phycocyanobilin, involving photoreversible conversion of λPCB max[Pr] 682 nm and λPCB max[Pfr] 734 nm, respectively. Our results suggest phycocyanobilin is also covalently bound to AM1_5894, while mutation of a cysteine residue (Cys11Ser) abolishes this covalent binding. The physiological function of AM1_5894 in cyanobacteria containing red-shifted chlorophylls is discussed.
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Affiliation(s)
- Patrick C Loughlin
- School of Biological Sciences, University of Sydney, NSW 2006, Australia
| | - Zane Duxbury
- School of Biological Sciences, University of Sydney, NSW 2006, Australia
| | | | - Penelope M C Smith
- School of Biological Sciences, University of Sydney, NSW 2006, Australia
| | - Robert D Willows
- Department of Chemistry and Biomolecular Sciences, Macquarie University, NSW 2109, Australia
| | - Min Chen
- School of Biological Sciences, University of Sydney, NSW 2006, Australia
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16
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Clarke VC, Loughlin PC, Gavrin A, Chen C, Brear EM, Day DA, Smith PMC. Proteomic analysis of the soybean symbiosome identifies new symbiotic proteins. Mol Cell Proteomics 2015; 14:1301-22. [PMID: 25724908 PMCID: PMC4424401 DOI: 10.1074/mcp.m114.043166] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 02/25/2015] [Indexed: 12/21/2022] Open
Abstract
Legumes form a symbiosis with rhizobia in which the plant provides an energy source to the rhizobia bacteria that it uses to fix atmospheric nitrogen. This nitrogen is provided to the legume plant, allowing it to grow without the addition of nitrogen fertilizer. As part of the symbiosis, the bacteria in the infected cells of a new root organ, the nodule, are surrounded by a plant-derived membrane, the symbiosome membrane, which becomes the interface between the symbionts. Fractions containing the symbiosome membrane (SM) and material from the lumen of the symbiosome (peribacteroid space or PBS) were isolated from soybean root nodules and analyzed using nongel proteomic techniques. Bicarbonate stripping and chloroform-methanol extraction of isolated SM were used to reduce complexity of the samples and enrich for hydrophobic integral membrane proteins. One hundred and ninety-seven proteins were identified as components of the SM, with an additional fifteen proteins identified from peripheral membrane and PBS protein fractions. Proteins involved in a range of cellular processes such as metabolism, protein folding and degradation, membrane trafficking, and solute transport were identified. These included a number of proteins previously localized to the SM, such as aquaglyceroporin nodulin 26, sulfate transporters, remorin, and Rab7 homologs. Among the proteome were a number of putative transporters for compounds such as sulfate, calcium, hydrogen ions, peptide/dicarboxylate, and nitrate, as well as transporters for which the substrate is not easy to predict. Analysis of the promoter activity for six genes encoding putative SM proteins showed nodule specific expression, with five showing expression only in infected cells. Localization of two proteins was confirmed using GFP-fusion experiments. The data have been deposited to the ProteomeXchange with identifier PXD001132. This proteome will provide a rich resource for the study of the legume-rhizobium symbiosis.
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Affiliation(s)
- Victoria C Clarke
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia
| | - Patrick C Loughlin
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia
| | - Aleksandr Gavrin
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia
| | - Chi Chen
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia
| | - Ella M Brear
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia
| | - David A Day
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia; §Flinders University, School of Biological Sciences, Adelaide Australia
| | - Penelope M C Smith
- From the ‡University of Sydney, School of Biological Sciences, Sydney Australia;
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17
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Clarke VC, Loughlin PC, Day DA, Smith PMC. Transport processes of the legume symbiosome membrane. Front Plant Sci 2014; 5:699. [PMID: 25566274 PMCID: PMC4266029 DOI: 10.3389/fpls.2014.00699] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 11/24/2014] [Indexed: 05/19/2023]
Abstract
The symbiosome membrane (SM) is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume:rhizobia symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is the transport of a carbon energy source from plant to bacteroid in exchange for fixed nitrogen. At a biochemical level two channels have been implicated in movement of fixed nitrogen across the SM and a uniporter that transports monovalent dicarboxylate ions has been characterized that would transport fixed carbon. The aquaporin NOD26 may provide a channel for ammonia, but the genes encoding the other transporters have not been identified. Transport of several other solutes, including calcium and potassium, have been demonstrated in isolated symbiosomes, and genes encoding transport systems for the movement of iron, nitrate, sulfate, and zinc in nodules have been identified. However, definitively matching transport activities with these genes has proved difficult and many further transport processes are expected on the SM to facilitate the movement of nutrients between the symbionts. Recently, work detailing the SM proteome in soybean has been completed, contributing significantly to the database of known SM proteins. This represents a valuable resource for the identification of transporter protein candidates, some of which may correspond to transport processes previously described, or to novel transport systems in the symbiosis. Putative transporters identified from the proteome include homologs of transporters of sulfate, calcium, peptides, and various metal ions. Here we review current knowledge of transport processes of the SM and discuss the requirements for additional transport routes of other nutrients exchanged in the symbiosis, with a focus on transport systems identified through the soybean SM proteome.
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Affiliation(s)
- Victoria C. Clarke
- School of Biological Sciences, University of Sydney, Sydney, NSW, Australia
| | | | - David A. Day
- School of Biological Sciences, Flinders University, Adelaide, SA, Australia
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18
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Brear EM, Day DA, Smith PMC. Iron: an essential micronutrient for the legume-rhizobium symbiosis. Front Plant Sci 2013; 4:359. [PMID: 24062758 PMCID: PMC3772312 DOI: 10.3389/fpls.2013.00359] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 08/26/2013] [Indexed: 05/19/2023]
Abstract
Legumes, which develop a symbiosis with nitrogen-fixing bacteria, have an increased demand for iron. Iron is required for the synthesis of iron-containing proteins in the host, including the highly abundant leghemoglobin, and in bacteroids for nitrogenase and cytochromes of the electron transport chain. Deficiencies in iron can affect initiation and development of the nodule. Within root cells, iron is chelated with organic acids such as citrate and nicotianamine and distributed to other parts of the plant. Transport to the nitrogen-fixing bacteroids in infected cells of nodules is more complicated. Formation of the symbiosis results in bacteroids internalized within root cortical cells of the legume where they are surrounded by a plant-derived membrane termed the symbiosome membrane (SM). This membrane forms an interface that regulates nutrient supply to the bacteroid. Consequently, iron must cross this membrane before being supplied to the bacteroid. Iron is transported across the SM as both ferric and ferrous iron. However, uptake of Fe(II) by both the symbiosome and bacteroid is faster than Fe(III) uptake. Members of more than one protein family may be responsible for Fe(II) transport across the SM. The only Fe(II) transporter in nodules characterized to date is GmDMT1 (Glycine max divalent metal transporter 1), which is located on the SM in soybean. Like the root plasma membrane, the SM has ferric iron reductase activity. The protein responsible has not been identified but is predicted to reduce ferric iron accumulated in the symbiosome space prior to uptake by the bacteroid. With the recent publication of a number of legume genomes including Medicago truncatula and G. max, a large number of additional candidate transport proteins have been identified. Members of the NRAMP (natural resistance-associated macrophage protein), YSL (yellow stripe-like), VIT (vacuolar iron transporter), and ZIP (Zrt-, Irt-like protein) transport families show enhanced expression in nodules and are expected to play a role in the transport of iron and other metals across symbiotic membranes.
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Affiliation(s)
- Ella M. Brear
- School of Biological Sciences, The University of SydneySydney, NSW, Australia
| | - David A. Day
- School of Biological Sciences, Flinders UniversityBedford Park, Adelaide, SA, Australia
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Walczyk NE, Smith PMC, Tovey E, Wright GC, Fleischfresser DB, Roberts TH. Analysis of crude protein and allergen abundance in peanuts (Arachis hypogaea cv. Walter) from three growing regions in Australia. J Agric Food Chem 2013; 61:3714-3725. [PMID: 23495786 DOI: 10.1021/jf305347r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The effects of plant growth conditions on concentrations of proteins, including allergens, in peanut ( Arachis hypogaea L.) kernels are largely unknown. Peanuts (cv. Walter) were grown at five sites (Taabinga, Redvale, Childers, Bundaberg, and Kairi) covering three commercial growing regions in Queensland, Australia. Differences in temperature, rainfall, and solar radiation during the growing season were evaluated. Kernel yield varied from 2.3 t/ha (Kairi) to 3.9 t/ha (Childers), probably due to differences in solar radiation. Crude protein appeared to vary only between Kairi and Childers, whereas Ara h 1 and 2 concentrations were similar in all locations. 2D-DIGE revealed significant differences in spot volumes for only two minor protein spots from peanuts grown in the five locations. Western blotting using peanut-allergic serum revealed no qualitative differences in recognition of antigens. It was concluded that peanuts grown in different growing regions in Queensland, Australia, had similar protein compositions and therefore were unlikely to show differences in allergenicity.
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Affiliation(s)
- Nicole E Walczyk
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
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20
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Atkins CA, Emery RJN, Smith PMC. Consequences of transforming narrow leafed lupin (Lupinus angustifolius [L.]) with an ipt gene under control of a flower-specific promoter. Transgenic Res 2011; 20:1321-32. [PMID: 21344295 DOI: 10.1007/s11248-011-9497-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 02/10/2011] [Indexed: 11/25/2022]
Abstract
Phenotypes of five transgenic lines of narrow-leafed lupin (Lupinus angustifolius [L] cv Merrit) stably transformed with the isopentenyl pyrophosphate transferase (ipt) gene from Agrobacterium tumefaciens coupled to a flower-specific promoter (TP12) from Nicotiana tabacum [L.] are described. Expression of the transgene was detected in floral tissues and in shoot apical meristems on all orders of inflorescence. In each transgenic line there was significant axillary bud outgrowth at all nodes on the main stem with pronounced branch development from the more basal nodes in three of the lines. The lowest basal branches developed in a manner similar to the upper stem axillary branches on cv Merrit and bore fruits, which, in two lines, contained a significant yield of filled seeds at maturity. Senescence of the cotyledons was delayed in all lines with green cotyledons persisting beyond anthesis in one case. IPT expression increased cytokinin (CK) levels in flowers, meristem tissues and phloem exudates in a form specific manner, which was suggestive of localized flower and meristem production with significant long-distance re-distribution in phloem. The total number of fruits formed (pod set) on some transgenic lines was increased compared to cv Merrit. Grain size compared to cv Merrit was not significantly altered in transgenic lines.
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Affiliation(s)
- Craig A Atkins
- School of Plant Biology, The University of Western Australia, Crawley, Perth, WA 6009, Australia.
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21
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Abstract
Plasmodesmata are plasma membrane-lined channels through which cytoplasmic molecules move from cell-to-cell in plants. Most plasmodesmata contain a desmotubule, a central tube of endoplasmic reticulum (ER), that connects the ER of adjacent cells. Here we demonstrate that molecules of up to 10.4 kDa in size can move between the ER lumen of neighbouring leaf trichome or epidermal cells via the desmotubule lumen. Fluorescent molecules of up to 10 kDa, microinjected into the ER of Nicotiana trichome cells, consistently moved into the ER and nuclei of neighbouring trichome cells. This movement occurred more rapidly than movement via the cytoplasmic pathway. A fluorescent 3-kDa dextran microinjected into the ER of a basal trichome cell moved into the ER and nuclei of epidermal cells across a barrier to cytoplasmic movement. We constructed a 10.4-kDa recombinant ER-lumenal reporter protein (LRP) from a fragment of the endogenous ER-lumenal binding protein AtBIP1. Following transient expression of the LRP in the ER of Tradescantia leaf epidermal cells, it often moved into the nuclear envelopes of neighbouring cells. However, green fluorescent protein targeted to the ER lumen (ER-GFP) did not move from cell to cell. We propose that the ER lumen of plant cells is continuous with that of their neighbours, and allows movement of small ER-lumenal molecules between cells.
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Affiliation(s)
- Deborah A Barton
- School of Biological Sciences, Macleay Building A12, University of Sydney, NSW 2006, Australia
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22
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Goggin DE, Mir G, Smith WB, Stuckey M, Smith PMC. Proteomic analysis of lupin seed proteins to identify conglutin Beta as an allergen, Lup an 1. J Agric Food Chem 2008; 56:6370-6377. [PMID: 18620408 DOI: 10.1021/jf800840u] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Lupin products may be valuable as human foods because of their high protein content and potential anticholesterolemic properties. However, a small percentage of the population is allergic to lupin. In this study, we use in vitro IgE binding and mass spectrometry to identify conglutin beta, a major storage protein, as an allergen in seeds of Lupinus angustifolius and Lupinus albus. Purification of conglutin beta from L. angustifolius flour confirmed that serum IgE binds to this protein. Where IgE in sera recognized lupin proteins on Western blots, it recognized conglutin beta, suggesting this protein is a major allergen for lupin. The L. angustifolius conglutin beta allergen has been designated Lup an 1 by the International Union of Immunological Societies (IUIS) allergen nomenclature subcommittee.
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Affiliation(s)
- Danica E Goggin
- School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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23
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Armstrong AF, Badger MR, Day DA, Barthet MM, Smith PMC, Millar AH, Whelan J, Atkin OK. Dynamic changes in the mitochondrial electron transport chain underpinning cold acclimation of leaf respiration. Plant Cell Environ 2008; 31:1156-1169. [PMID: 18507806 DOI: 10.1111/j.1365-3040.2008.01830.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We examined the effect of short- and long-term changes in temperature on gene expression, protein abundance, and the activity of the alternative oxidase and cytochrome oxidase pathways (AOP and COP, respectively) in Arabidopsis thaliana. The AOP was more sensitive to short-term changes in temperature than the COP, with partitioning to the AOP decreasing significantly below a threshold temperature of 20 degrees C. AOP activity was increased in leaves, which had been shifted to the cold for several days, but this response was transient, with AOP activity subsiding (and COP activity increasing) following the development of leaves in the cold. The transient increase in AOP activity in 10-d cold-shifted leaves was not associated with an increase in alternative oxidase (AOX) protein or AOX1a transcript abundance. By contrast, the amount of uncoupling protein was significantly increased in cold-developed leaves. In conjunction with this, transcript levels of the uncoupling protein-encoding gene UCP1 and the external NAD(P)H dehydrogenase-encoding gene NDB2 exhibited sustained increases following growth in the cold. The data suggest a role for each of these alternative non-phosphorylating bypasses of mitochondrial electron transport at different points in time following exposure to cold, with increased AOP activity being important only in the early stages of cold treatment.
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Affiliation(s)
- Anna F Armstrong
- Department of Biology, University of York, PO Box 373, York, YO10 5YW, UK
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Bussell JD, Hall DJ, Mann AJ, Goggin DE, Atkins CA, Smith PMC. Alternative splicing of the Vupur3 transcript in cowpea produces multiple mRNA species with a single protein product that is present in both plastids and mitochondria. Funct Plant Biol 2005; 32:683-693. [PMID: 32689167 DOI: 10.1071/fp05044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2005] [Accepted: 04/28/2005] [Indexed: 06/11/2023]
Abstract
A heterogeneous population of cDNAs (designated Vupur3) encoding phosphoribosylglycinamide formyltransferase (GART; EC 2.1.2.2) was isolated from a cowpea (Vigna unguiculata L. Walp.) nodule library. Three classes of cDNA with the same ORF, but differing in their 3'-UTRs, were identified. Southern analysis and sequencing of genomic DNA confirmed that these differences result from alternative splicing of the primary transcript of a single Vupur3 gene. Alternative splicing does not appear to play a role in the production of soybean (Glycine max Merrill.) pur3 transcripts. The presence of the protein product of the Vupur3 gene, GART, in plastids and mitochondria was confirmed by immunoblotting with antibodies raised against the recombinant protein. The antibodies recognised two proteins with apparent molecular masses of 27 and 27.5 kDa in both mitochondria and plastids. All Vupur3 transcripts have two in-frame start codons that are active in wheatgerm in vitro transcription / translation experiments suggesting a mechanism by which the gene product could be targeted to two organelles. Like other genes encoding enzymes for purine synthesis, Vupur3 is expressed in nodules before nitrogen fixation begins but in contrast to these genes its expression does not increase markedly after nitrogen fixation begins.
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Affiliation(s)
- John D Bussell
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Doug J Hall
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Anthea J Mann
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Danica E Goggin
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Craig A Atkins
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Penelope M C Smith
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
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Smith PMC, Winter H, Storer PJ, Bussell JD, Schuller KA, Atkins CA. Effect of short-term N(2) deficiency on expression of the ureide pathway in cowpea root nodules. Plant Physiol 2002; 129:1216-1221. [PMID: 12114575 PMCID: PMC166515 DOI: 10.1104/pp.010714] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2001] [Revised: 02/18/2002] [Accepted: 03/18/2002] [Indexed: 05/23/2023]
Abstract
Root systems of 28-d-old cowpea (Vigna unguiculata L. Walp cv Vita 3: Bradyrhizobium sp. strain CB756) plants bearing nitrogen-fixing nodules in sand culture were exposed to an atmosphere of Ar:O(2) (80:20, v/v) for 48 h and then returned to air. Root systems of control plants were maintained in air throughout. Nodules were harvested at the same times in control and Ar:O(2)-treated root systems. Activities of two enzymes of de novo purine synthesis, glycinamide ribonucleotide transformylase (GART; EC 2.1.2.2), aminoimidazole ribonucleotide synthetase (AIRS; EC 6.3.3.1), uricase (EC 1.7.3.3), and phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) were measured together with the protein level of each using immune-specific polyclonal antibodies. AIRS activity and protein both declined to very low levels within 6 h in Ar:O(2) together with a decline in transcript level of pur5, the encoding gene. GART activity, protein, and transcript (pur3) levels were relatively stable. Uricase activity declined in Ar:O(2) as rapidly as AIRS activity but the protein was stable. PEPC activity showed evidence of increased sensitivity to inhibition by malate but the protein level was stable. The data indicate that the flux of fixed N from bacteroids (N(2)-fixing nodule bacteria) is in some way associated with transcriptional control over pur5 and possibly also catabolism of AIRS protein. In contrast, there is limited posttranslational control over GART and PEPC and close posttranslational control over uricase activity. The significance of these different levels of regulation is discussed in relation to the overall control of enhanced expression of plant enzymes in the cowpea symbiosis.
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Affiliation(s)
- Penelope M C Smith
- Botany Department, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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Affiliation(s)
- Penelope M C Smith
- Botany Department, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
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