1
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Yang B, Wang J, Yu M, Zhang M, Zhong Y, Wang T, Liu P, Song W, Zhao H, Fastner A, Suter M, Rentsch D, Ludewig U, Jin W, Geiger D, Hedrich R, Braun DM, Koch KE, McCarty DR, Wu WH, Li X, Wang Y, Lai J. The sugar transporter ZmSUGCAR1 of the nitrate transporter 1/peptide transporter family is critical for maize grain filling. Plant Cell 2022; 34:4232-4254. [PMID: 36047828 PMCID: PMC9614462 DOI: 10.1093/plcell/koac256] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 07/31/2022] [Indexed: 05/07/2023]
Abstract
Maternal-to-filial nutrition transfer is central to grain development and yield. nitrate transporter 1/peptide transporter (NRT1-PTR)-type transporters typically transport nitrate, peptides, and ions. Here, we report the identification of a maize (Zea mays) NRT1-PTR-type transporter that transports sucrose and glucose. The activity of this sugar transporter, named Sucrose and Glucose Carrier 1 (SUGCAR1), was systematically verified by tracer-labeled sugar uptake and serial electrophysiological studies including two-electrode voltage-clamp, non-invasive microelectrode ion flux estimation assays in Xenopus laevis oocytes and patch clamping in HEK293T cells. ZmSUGCAR1 is specifically expressed in the basal endosperm transfer layer and loss-of-function mutation of ZmSUGCAR1 caused significantly decreased sucrose and glucose contents and subsequent shrinkage of maize kernels. Notably, the ZmSUGCAR1 orthologs SbSUGCAR1 (from Sorghum bicolor) and TaSUGCAR1 (from Triticum aestivum) displayed similar sugar transport activities in oocytes, supporting the functional conservation of SUGCAR1 in closely related cereal species. Thus, the discovery of ZmSUGCAR1 uncovers a type of sugar transporter essential for grain development and opens potential avenues for genetic improvement of seed-filling and yield in maize and other grain crops.
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Affiliation(s)
- Bo Yang
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Jing Wang
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Miao Yu
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB), College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Meiling Zhang
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Yanting Zhong
- The Key Laboratory of Plant–Soil Interactions (MOE), Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Tianyi Wang
- National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Peng Liu
- Plant Molecular and Cellular Biology Program, Horticultural Sciences Department, Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Weibin Song
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Haiming Zhao
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
| | - Astrid Fastner
- Institute of Plant Sciences, University of Bern, Bern 3013, Switzerland
| | - Marianne Suter
- Institute of Plant Sciences, University of Bern, Bern 3013, Switzerland
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern 3013, Switzerland
| | - Uwe Ludewig
- Institute of Crop Science, Nutritional Crop Physiology (340h), University of Hohenheim, Stuttgart 70593, Germany
| | - Weiwei Jin
- National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Dietmar Geiger
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute for Biosciences, University of Würzburg, Würzburg 97082, Germany
| | - Rainer Hedrich
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute for Biosciences, University of Würzburg, Würzburg 97082, Germany
| | - David M Braun
- Division of Biological Sciences, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, 116 Tucker Hall, Columbia, Missouri 65211, USA
| | - Karen E Koch
- Plant Molecular and Cellular Biology Program, Horticultural Sciences Department, Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Donald R McCarty
- Plant Molecular and Cellular Biology Program, Horticultural Sciences Department, Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Wei-Hua Wu
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB), College of Biological Sciences, China Agricultural University, Beijing 100193, China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Xuexian Li
- The Key Laboratory of Plant–Soil Interactions (MOE), Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Yi Wang
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB), College of Biological Sciences, China Agricultural University, Beijing 100193, China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Jinsheng Lai
- State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China
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2
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Gavrin A, Loughlin PC, Brear E, Griffith OW, Bedon F, Suter Grotemeyer M, Escudero V, Reguera M, Qu Y, Mohd-Noor SN, Chen C, Osorio MB, Rentsch D, González-Guerrero M, Day DA, Smith PMC. Soybean Yellow Stripe-like 7 is a symbiosome membrane peptide transporter important for nitrogen fixation. Plant Physiol 2021; 186:581-598. [PMID: 33619553 PMCID: PMC8154080 DOI: 10.1093/plphys/kiab044] [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] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 01/21/2021] [Indexed: 05/05/2023]
Abstract
Legumes form a symbiosis with rhizobia that convert atmospheric nitrogen (N2) to ammonia and provide it to the plant in return for a carbon and nutrient supply. Nodules, developed as part of the symbiosis, harbor rhizobia that are enclosed in a plant-derived symbiosome membrane (SM) to form an organelle-like structure called the symbiosome. In mature nodules exchanges between the symbionts occur across the SM. Here we characterize Yellow Stripe-like 7 (GmYSL7), a Yellow stripe-like family member localized on the SM in soybean (Glycine max) nodules. It is expressed specifically in infected cells with expression peaking soon after nitrogenase becomes active. Unlike most YSL family members, GmYSL7 does not transport metals complexed with phytosiderophores. Rather, it transports oligopeptides of between four and 12 amino acids. Silencing GmYSL7 reduces nitrogenase activity and blocks infected cell development so that symbiosomes contain only a single bacteroid. This indicates the substrate of YSL7 is required for proper nodule development, either by promoting symbiosome development directly or by preventing inhibition of development by the plant. RNAseq of nodules where GmYSL7 was silenced suggests that the plant initiates a defense response against rhizobia with genes encoding proteins involved in amino acid export downregulated and some transcripts associated with metal homeostasis altered. These changes may result from the decrease in nitrogen fixation upon GmYSL7 silencing and suggest that the peptide(s) transported by GmYSL7 monitor the functional state of the bacteroids and regulate nodule metabolism and transport processes accordingly. Further work to identify the physiological substrate for GmYSL7 will allow clarification of this role.
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Affiliation(s)
- Aleksandr Gavrin
- Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, UK
| | - Patrick C Loughlin
- School of Life and Environmental Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Ella Brear
- School of Life and Environmental Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Oliver W Griffith
- Department of Biological Sciences, Macquarie University, Macquarie Park, NSW 2109, Australia
| | - Frank Bedon
- School of Life Sciences, La Trobe University, Bundoora, Victoria 3083, Australia
| | | | - Viviana Escudero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Crta, 28223 Pozuelo de Alarcón (Madrid), Spain
| | - Maria Reguera
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Crta, 28223 Pozuelo de Alarcón (Madrid), Spain
| | - Yihan Qu
- School of Life and Environmental Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Siti N Mohd-Noor
- School of Life and Environmental Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Chi Chen
- School of Life and Environmental Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Marina Borges Osorio
- School of Life Sciences, La Trobe University, Bundoora, Victoria 3083, Australia
| | - Doris Rentsch
- IPS, Molecular Plant Physiology, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA). Universidad Politécnica de Madrid, Campus de Montegancedo, Crta, 28223 Pozuelo de Alarcón (Madrid), Spain
| | - David A Day
- College of Science and Engineering, Flinders University, Bedford Park, Adelaide, SA, Australia
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3
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Wan Y, Wang Y, Shi Z, Rentsch D, Ward JL, Hassall K, Sparks CA, Huttly AK, Buchner P, Powers S, Shewry PR, Hawkesford MJ. Wheat amino acid transporters highly expressed in grain cells regulate amino acid accumulation in grain. PLoS One 2021; 16:e0246763. [PMID: 33606697 PMCID: PMC7894817 DOI: 10.1371/journal.pone.0246763] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/25/2021] [Indexed: 11/18/2022] Open
Abstract
Amino acids are delivered into developing wheat grains to support the accumulation of storage proteins in the starchy endosperm, and transporters play important roles in regulating this process. RNA-seq, RT-qPCR, and promoter-GUS assays showed that three amino acid transporters are differentially expressed in the endosperm transfer cells (TaAAP2), starchy endosperm cells (TaAAP13), and aleurone cells and embryo of the developing grain (TaAAP21), respectively. Yeast complementation revealed that all three transporters can transport a broad spectrum of amino acids. RNAi-mediated suppression of TaAAP13 expression in the starchy endosperm did not reduce the total nitrogen content of the whole grain, but significantly altered the composition and distribution of metabolites in the starchy endosperm, with increasing concentrations of some amino acids (notably glutamine and glycine) from the outer to inner starchy endosperm cells compared with wild type. Overexpression of TaAAP13 under the endosperm-specific HMW-GS (high molecular weight glutenin subunit) promoter significantly increased grain size, grain nitrogen concentration, and thousand grain weight, indicating that the sink strength for nitrogen transport was increased by manipulation of amino acid transporters. However, the total grain number was reduced, suggesting that source nitrogen remobilized from leaves is a limiting factor for productivity. Therefore, simultaneously increasing loading of amino acids into the phloem and delivery to the spike would be required to increase protein content while maintaining grain yield.
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Affiliation(s)
- Yongfang Wan
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Yan Wang
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
- Triticeae Institute, Sichuan Agricultural University, Sichuan, P. R. China
| | - Zhiqiang Shi
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
- National Technology Innovation Center for Regional Wheat Production, Key Laboratory of Crop Physiology, and Ecology and Production in Southern China, Ministry of Agriculture, National Engineering and Technology Center for Information Agriculture, Nanjing Agricultural University, Nanjing, P. R. China
| | - Doris Rentsch
- University of Bern, Molecular Plant Physiology, Bern, Switzerland
| | - Jane L. Ward
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Kirsty Hassall
- Computational and Analytical Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Caroline A. Sparks
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Alison K. Huttly
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Peter Buchner
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Stephen Powers
- Computational and Analytical Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Peter R. Shewry
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Malcolm J. Hawkesford
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
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4
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Haindrich AC, Ernst V, Naguleswaran A, Oliveres QF, Roditi I, Rentsch D. Nutrient availability regulates proline/alanine transporters in Trypanosoma brucei. J Biol Chem 2021; 296:100566. [PMID: 33745971 PMCID: PMC8094907 DOI: 10.1016/j.jbc.2021.100566] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 03/09/2021] [Accepted: 03/17/2021] [Indexed: 11/23/2022] Open
Abstract
Trypanosoma brucei is a species of unicellular parasite that can cause severe diseases in livestock and humans, including African trypanosomiasis and Chagas disease. Adaptation to diverse environments and changes in nutritional conditions is essential for T. brucei to establish an infection when changing hosts or during invasion of different host tissues. One such adaptation is the ability of T. brucei to rapidly switch its energy metabolism from glucose metabolism in the mammalian blood to proline catabolism in the insect stages and vice versa. However, the mechanisms that support the parasite's response to nutrient availability remain unclear. Using RNAseq and qRT-PCR, we investigated the response of T. brucei to amino acid or glucose starvation and found increased mRNA levels of several amino acid transporters, including all genes of the amino acid transporter AAT7-B subgroup. Functional characterization revealed that AAT7-B members are plasma membrane-localized in T. brucei and when expressed in Saccharomyces cerevisiae supported the uptake of proline, alanine, and cysteine, while other amino acids were poorly recognized. All AAT7-B members showed a preference for proline, which is transported with high or low affinity. RNAi-mediated AAT7-B downregulation resulted in a reduction of intracellular proline concentrations and growth arrest under low proline availability in cultured procyclic form parasites. Taken together, these results suggest a role of AAT7-B transporters in the response of T. brucei to proline starvation and proline catabolism.
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Affiliation(s)
| | - Viona Ernst
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | | | | | - Isabel Roditi
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern, Switzerland.
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5
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Kolbe V, Rentsch D, Boy D, Schmidt B, Kegler R, Büttner A. The adulterated XANAX pill: a fatal intoxication with etizolam and caffeine. Int J Legal Med 2020; 134:1727-1731. [PMID: 32607751 PMCID: PMC7417405 DOI: 10.1007/s00414-020-02352-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 06/18/2020] [Indexed: 12/29/2022]
Abstract
A 49-year old man was found dead at home next to a glass containing a dried, white, crystalline substance and near a bag containing pills with the imprint XANAX, the trade name of alprazolam. A comprehensive screening of material collected during the autopsy revealed the presence of etizolam and caffeine in lethal concentrations (0.77 μg/mL and 190 μg/mL) but no trace of alprazolam. Benzodiazepine analogue etizolam is rarely prescribed in Germany, and as a result there are not many reports about fatal cases. It has anxiolytic, hypnotic, sedative and muscle-relaxant properties and is used for the short-term treatment of anxiety and panic attacks. The purine alkaloid caffeine, conversely, is the most widely used central nervous system stimulant. The following report outlines potentially the first reported case of a lethal combination of the downer etizolam and the upper caffeine in medical literature.
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Affiliation(s)
- V Kolbe
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany.
| | - D Rentsch
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany
| | - D Boy
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany
| | - B Schmidt
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany
| | - R Kegler
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany
| | - A Büttner
- Institute of Legal Medicine, University Medical Center, St.-Georg-Strasse 108, 18055, Rostock, Germany
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6
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Liburkin-Dan T, Schlisselberg D, Fischer-Weinberger R, Pescher P, Inbar E, Ephros M, Rentsch D, Späth GF, Zilberstein D. Stage-specific expression of the proline-alanine transporter in the human pathogen Leishmania. Mol Biochem Parasitol 2018; 222:1-5. [PMID: 29655799 DOI: 10.1016/j.molbiopara.2018.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/03/2018] [Accepted: 04/09/2018] [Indexed: 11/26/2022]
Abstract
Leishmania are obligatory intracellular parasites that cycle between the sand fly midgut (extracellular promastigotes) and mammalian macrophage phagolysosomes (intracellular amastigotes). They have developed mechanisms of adaptation to the distinct environments of host and vector that favor utilization of both proline and alanine. LdAAP24 is the L. donovani proline-alanine transporter. It is a member of Leishmania system A that translocates neutral amino acids. Since system A is promastigote-specific, we aimed to assess whether LdAAP24 is also expressed exclusively in promastigotes. Herein, we established that upon exposing L. donovani promastigotes to amastigote differentiation signal (pH 5.5 and 37 °C), parasites rapidly and completely degrade LdAAP24 protein in both axenic and in spleen-derived amastigotes. In contrast, LdAAP24 mRNA remained unchanged throughout differentiation. Addition of either MG132 or Bafilomycin A1 partially inhibited LdAAP24 protein degradation, indicating a role for both lysosome- and proteasome-mediated degradation. This work provides the first evidence for post-translational regulation of stage-specific expression of LdAAP24.
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Affiliation(s)
- T Liburkin-Dan
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel
| | - D Schlisselberg
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel
| | - R Fischer-Weinberger
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel
| | - P Pescher
- Institut Pasteur, INSERM U1201, Unité de Parasitologie moléculaire et Signalisation, 75015 Paris, France
| | - E Inbar
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel
| | - M Ephros
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel
| | - D Rentsch
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - G F Späth
- Institut Pasteur, INSERM U1201, Unité de Parasitologie moléculaire et Signalisation, 75015 Paris, France
| | - D Zilberstein
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa 3200003, Haifa, Israel.
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7
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Abstract
This communication presents the first synthesis of nanoconfined Lithium closo-borate, Li2B12H12, using nanoporous SiO2 as scaffold. The yield of Li2B12H12 is up to 94 mol%. The as-synthesized nanoconfined Li2B12H12 exhibits a structural transition around 380 °C and conversion to H-deficiency Li2B12H12-x at 580 °C.
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Affiliation(s)
- Y Yan
- Center for Materials Crystallography, Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark.
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8
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Steinmann ME, Schmidt RS, Macêdo JP, Kunz Renggli C, Bütikofer P, Rentsch D, Mäser P, Sigel E. Identification and characterization of the three members of the CLC family of anion transport proteins in Trypanosoma brucei. PLoS One 2017; 12:e0188219. [PMID: 29244877 PMCID: PMC5731698 DOI: 10.1371/journal.pone.0188219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/02/2017] [Indexed: 11/19/2022] Open
Abstract
CLC type anion transport proteins are homo-dimeric or hetero-dimeric with an integrated transport function in each subunit. We have identified and partially characterized three members of this family named TbVCL1, TbVCL2 and TbVCL3 in Trypanosoma brucei. Among the human CLC family members, the T. brucei proteins display highest similarity to CLC-6 and CLC-7. TbVCL1, but not TbVCL2 and TbVCL3 is able to complement growth of a CLC-deficient Saccharomyces cerevisiae mutant. All TbVCL-HA fusion proteins localize intracellulary in procyclic form trypanosomes. TbVCL1 localizes close to the Golgi apparatus and TbVCL2 and TbVCL3 to the endoplasmic reticulum. Upon expression in Xenopus oocytes, all three proteins induce similar outward rectifying chloride ion currents. Currents are sensitive to low concentrations of DIDS, insensitive to the pH in the range 5.4 to 8.4 and larger in nitrate than in chloride medium.
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Affiliation(s)
- Michael E. Steinmann
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - Remo S. Schmidt
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Juan P. Macêdo
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Christina Kunz Renggli
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Erwin Sigel
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
- * E-mail:
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9
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Schmidt RS, Macêdo JP, Steinmann ME, Salgado AG, Bütikofer P, Sigel E, Rentsch D, Mäser P. Transporters of Trypanosoma brucei-phylogeny, physiology, pharmacology. FEBS J 2017; 285:1012-1023. [PMID: 29063677 DOI: 10.1111/febs.14302] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/18/2017] [Accepted: 10/18/2017] [Indexed: 12/12/2022]
Abstract
Trypanosoma brucei comprise the causative agents of sleeping sickness, T. b. gambiense and T. b. rhodesiense, as well as the livestock-pathogenic T. b. brucei. The parasites are transmitted by the tsetse fly and occur exclusively in sub-Saharan Africa. T. brucei are not only lethal pathogens but have also become model organisms for molecular parasitology. We focus here on membrane transport proteins of T. brucei, their contribution to homeostasis and metabolism in the context of a parasitic lifestyle, and their pharmacological role as potential drug targets or routes of drug entry. Transporters and channels in the plasma membrane are attractive drug targets as they are accessible from the outside. Alternatively, they can be exploited to selectively deliver harmful substances into the trypanosome's interior. Both approaches require the targeted transporter to be essential: in the first case to kill the trypanosome, in the second case to prevent drug resistance due to loss of the transporter. By combining functional and phylogenetic analyses, we were mining the T. brucei predicted proteome for transporters of pharmacological significance. Here, we review recent progress in the identification of transporters of lipid precursors, amino acid permeases and ion channels in T. brucei.
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Affiliation(s)
- Remo S Schmidt
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Switzerland
| | - Juan P Macêdo
- Institute of Plant Sciences, University of Bern, Switzerland
| | - Michael E Steinmann
- Institute of Biochemistry and Molecular Medicine, University of Bern, Switzerland
| | | | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, Switzerland
| | - Erwin Sigel
- Institute of Biochemistry and Molecular Medicine, University of Bern, Switzerland
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Switzerland
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Switzerland
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10
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Giehl RFH, Laginha AM, Duan F, Rentsch D, Yuan L, von Wirén N. A Critical Role of AMT2;1 in Root-To-Shoot Translocation of Ammonium in Arabidopsis. Mol Plant 2017; 10:1449-1460. [PMID: 29032248 DOI: 10.1016/j.molp.2017.10.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [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: 02/24/2017] [Revised: 09/01/2017] [Accepted: 10/01/2017] [Indexed: 05/24/2023]
Abstract
Ammonium uptake in plant roots is mediated by AMT/MEP/Rh-type ammonium transporters. Out of five AMTs being expressed in Arabidopsis roots, four AMT1-type transporters contribute to ammonium uptake, whereas no physiological function has so far been assigned to the only homolog belonging to the MEP subfamily, AMT2;1. Based on the observation that under ammonium supply, the transcript levels of AMT2;1 increased and its promoter activity shifted preferentially to the pericycle, we assessed the contribution of AMT2;1 to xylem loading. When exposed to 15N-labeled ammonium, amt2;1 mutant lines translocated less tracer to the shoots and contained less ammonium in the xylem sap. Moreover, in an amt1;1 amt1;2 amt1;3 amt2;1 quadruple mutant (qko), co-expression of AMT2;1 with either AMT1;2 or AMT1;3 significantly enhanced 15N translocation to shoots, indicating a cooperative action between AMT2;1 and AMT1 transporters. Under N deficiency, proAMT2;1-GFP lines showed enhanced promoter activity predominantly in cortical root cells, which coincided with elevated ammonium influx conferred by AMT2;1 at millimolar substrate concentrations. Our results indicate that in addition to contributing moderately to root uptake in the low-affinity range, AMT2;1 functions mainly in root-to-shoot translocation of ammonium, depending on its cell-type-specific expression in response to the plant nutritional status and to local ammonium gradients.
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Affiliation(s)
- Ricardo F H Giehl
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany
| | - Alberto M Laginha
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany
| | - Fengying Duan
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Lixing Yuan
- Key Lab of Plant-Soil Interaction, MOE, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Nicolaus von Wirén
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany.
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11
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12
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Macedo JP, Currier RB, Wirdnam C, Horn D, Alsford S, Rentsch D. Ornithine uptake and the modulation of drug sensitivity in Trypanosoma brucei. FASEB J 2017; 31:4649-4660. [PMID: 28679527 PMCID: PMC5602898 DOI: 10.1096/fj.201700311r] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/27/2017] [Indexed: 12/02/2022]
Abstract
Trypanosoma brucei, protozoan parasites that cause human African trypanosomiasis (HAT), depend on ornithine uptake and metabolism by ornithine decarboxylase (ODC) for survival. Indeed, ODC is the target of the WHO “essential medicine” eflornithine, which is antagonistic to another anti-HAT drug, suramin. Thus, ornithine uptake has important consequences in T. brucei, but the transporters have not been identified. We describe these amino acid transporters (AATs). In a heterologous expression system, TbAAT10-1 is selective for ornithine, whereas TbAAT2-4 transports both ornithine and histidine. These AATs are also necessary to maintain intracellular ornithine and polyamine levels in T. brucei, thereby decreasing sensitivity to eflornithine and increasing sensitivity to suramin. Consistent with competition for histidine, high extracellular concentrations of this amino acid phenocopied a TbAAT2-4 genetic defect. Our findings established TbAAT10-1 and TbAAT2-4 as the parasite ornithine transporters, one of which can be modulated by histidine, but both of which affect sensitivity to important anti-HAT drugs.—Macedo, J. P., Currier, R. B., Wirdnam, C., Horn, D., Alsford, S., Rentsch, D. Ornithine uptake and the modulation of drug sensitivity in Trypanosoma brucei.
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Affiliation(s)
- Juan P Macedo
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Rachel B Currier
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Corina Wirdnam
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - David Horn
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Sam Alsford
- London School of Hygiene and Tropical Medicine, London, United Kingdom;
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern, Switzerland;
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13
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Mathieu C, Macêdo JP, Hürlimann D, Wirdnam C, Haindrich AC, Suter Grotemeyer M, González-Salgado A, Schmidt RS, Inbar E, Mäser P, Bütikofer P, Zilberstein D, Rentsch D. Arginine and Lysine Transporters Are Essential for Trypanosoma brucei. PLoS One 2017; 12:e0168775. [PMID: 28045943 PMCID: PMC5207785 DOI: 10.1371/journal.pone.0168775] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 12/06/2016] [Indexed: 12/14/2022] Open
Abstract
For Trypanosoma brucei arginine and lysine are essential amino acids and therefore have to be imported from the host. Heterologous expression in Saccharomyces cerevisiae mutants identified cationic amino acid transporters among members of the T. brucei AAAP (amino acid/auxin permease) family. TbAAT5-3 showed high affinity arginine uptake (Km 3.6 ± 0.4 μM) and high selectivity for L-arginine. L-arginine transport was reduced by a 10-times excess of L-arginine, homo-arginine, canavanine or arginine-β-naphthylamide, while lysine was inhibitory only at 100-times excess, and histidine or ornithine did not reduce arginine uptake rates significantly. TbAAT16-1 is a high affinity (Km 4.3 ± 0.5 μM) and highly selective L-lysine transporter and of the compounds tested, only L-lysine and thialysine were competing for L-lysine uptake. TbAAT5-3 and TbAAT16-1 are expressed in both procyclic and bloodstream form T. brucei and cMyc-tagged proteins indicate localization at the plasma membrane. RNAi-mediated down-regulation of TbAAT5 and TbAAT16 in bloodstream form trypanosomes resulted in growth arrest, demonstrating that TbAAT5-mediated arginine and TbAAT16-mediated lysine transport are essential for T. brucei. Growth of induced RNAi lines could partially be rescued by supplementing a surplus of arginine or lysine, respectively, while addition of both amino acids was less efficient. Single and double RNAi lines indicate that additional low affinity uptake systems for arginine and lysine are present in T. brucei.
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Affiliation(s)
| | - Juan P. Macêdo
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Daniel Hürlimann
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Corina Wirdnam
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | | | | | | | - Remo S. Schmidt
- Swiss Tropical and Public Health Institute and University of Basel, Basel, Switzerland
| | - Ehud Inbar
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute and University of Basel, Basel, Switzerland
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - Dan Zilberstein
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
- * E-mail:
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Duchêne L, Kühnel RS, Rentsch D, Remhof A, Hagemann H, Battaglia C. A highly stable sodium solid-state electrolyte based on a dodeca/deca-borate equimolar mixture. Chem Commun (Camb) 2017; 53:4195-4198. [DOI: 10.1039/c7cc00794a] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Na2(B12H12)0.5(B10H10)0.5, a new solid-state sodium electrolyte is shown to offer high Na+ conductivity of 0.9 mS cm−1 at 20 °C.
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Affiliation(s)
- L. Duchêne
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
- Département de Chimie-Physique
| | - R.-S. Kühnel
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
| | - D. Rentsch
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
| | - A. Remhof
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
| | - H. Hagemann
- Département de Chimie-Physique
- Université de Genève
- CH-1211 Geneva 4
- Switzerland
| | - C. Battaglia
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
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15
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Abstract
The formation of CaB6 from the thermal decomposition of Ca(BH4)2 goes along two distinct routes, i.e. via CaB2H6 or elemental boron as a reaction intermediate, depending on temperature.
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Affiliation(s)
- Y. Yan
- Interdisciplinary Nanoscience Center (iNANO)
- Aarhus University
- DK-8000 Aarhus C
- Denmark
- EMPA
| | - D. Rentsch
- EMPA
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
| | - A. Remhof
- EMPA
- Swiss Federal Laboratories for Materials Science and Technology
- CH-8600 Dübendorf
- Switzerland
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Bernius A, Blaas V, Rentsch D, Büttner A, Thome J. [Unexpected Complications in the Withdrawal Treatment of the Research Chemical AH-7921]. Fortschr Neurol Psychiatr 2016; 84:S80-S83. [PMID: 27806420 DOI: 10.1055/s-0042-113960] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
We describe the case of a young male patient who had consumed the morphine-like substance AH-7921 which is available via the internet. He was initially admitted to hospital because of obstipation and presented within a day of inpatient treatment for the first time with a generalized tonic-clonic epileptic seizure with subsequent urinary retention. Within a few hours, the patient then also developed bradycardia, while at the same time describing symptoms of physical opioid withdrawal which gradually deteriorated within the following hours. We initiated a treatment with buprenorphine which resulted in a considerable reduction of withdrawal symptoms, so the patient could be discharged from hospital.
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Affiliation(s)
- A Bernius
- Klinik und Poliklinik für Psychiatrie und Psychotherapie, Universitätsmedizin Rostock
| | - V Blaas
- Institut für Rechtsmedizin, Universitätsmedizin Rostock
| | - D Rentsch
- Institut für Rechtsmedizin, Universitätsmedizin Rostock
| | - A Büttner
- Institut für Rechtsmedizin, Universitätsmedizin Rostock
| | - J Thome
- Klinik und Poliklinik für Psychiatrie und Psychotherapie, Universitätsmedizin Rostock
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Goldman-Pinkovich A, Balno C, Strasser R, Zeituni-Molad M, Bendelak K, Rentsch D, Ephros M, Wiese M, Jardim A, Myler PJ, Zilberstein D. An Arginine Deprivation Response Pathway Is Induced in Leishmania during Macrophage Invasion. PLoS Pathog 2016; 12:e1005494. [PMID: 27043018 PMCID: PMC4846328 DOI: 10.1371/journal.ppat.1005494] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/15/2016] [Indexed: 11/18/2022] Open
Abstract
Amino acid sensing is an intracellular function that supports nutrient homeostasis, largely through controlled release of amino acids from lysosomal pools. The intracellular pathogen Leishmania resides and proliferates within human macrophage phagolysosomes. Here we describe a new pathway in Leishmania that specifically senses the extracellular levels of arginine, an amino acid that is essential for the parasite. During infection, the macrophage arginine pool is depleted due to its use to produce metabolites (NO and polyamines) that constitute part of the host defense response and its suppression, respectively. We found that parasites respond to this shortage of arginine by up-regulating expression and activity of the Leishmania arginine transporter (LdAAP3), as well as several other transporters. Our analysis indicates the parasite monitors arginine levels in the environment rather than the intracellular pools. Phosphoproteomics and genetic analysis indicates that the arginine-deprivation response is mediated through a mitogen-activated protein kinase-2-dependent signaling cascade. Protozoa of the genus Leishmania are the causative agents of leishmaniasis in humans. These parasites cycle between promastigotes in the sand fly mid-gut and amastigotes in phagolysosome of mammalian macrophages. During infection, host cells up-regulate nitric oxide while/or parasites induce expression of host arginase, both of which use arginine as a substrate. These elevated activities deplete macrophage arginine pools, a situation that invading Leishmania must overcome since it is an essential amino acid. Leishmania donovani imports exogenous arginine via a mono-specific amino acid transporter (AAP3) and utilizes it primarily through the polyamine pathway to provide precursors for trypanothione biosynthesis as well as hypusination of eukaryotic translation Initiation Factor 5A. Here we report the discovery of a pathway whereby Leishmania sense the lack of environmental arginine and respond with rapid up-regulation in the expression and activity of AAP3, as well as several other transporters. Significantly, this arginine deprivation response is also activated in parasites during macrophage infection. Phosphoproteomic analyses of L. donovani promastigotes have implicated a mitogen-activated protein kinase 2 (MPK2)-mediated signaling cascade in this response, and L. mexicana mutants lacking MPK2 are unable to respond to arginine deprivation. The arginine-sensing pathway might play an important role in Leishmania virulence and hence serve as target for drug development.
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Affiliation(s)
| | - Caitlin Balno
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa, Haifa, Israel
| | - Rona Strasser
- Institute of Parasitology, McGill University, Ste Anne de Bellevue, Quebec, Canada
| | - Michal Zeituni-Molad
- Carmel Medical Center and Faculty of Medicine, Technion,—Israel institute of Technology, Haifa, Israel
| | - Keren Bendelak
- The Smoler Proteomic Center, Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Moshe Ephros
- Carmel Medical Center and Faculty of Medicine, Technion,—Israel institute of Technology, Haifa, Israel
| | - Martin Wiese
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Armando Jardim
- Institute of Parasitology, McGill University, Ste Anne de Bellevue, Quebec, Canada
| | - Peter J. Myler
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, United States of America
- Departments of Global Health and Biomedical Informatics & Medical Education, University of Washington, Seattle, Washington, United States of America
| | - Dan Zilberstein
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa, Haifa, Israel
- * E-mail:
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Müller B, Fastner A, Karmann J, Mansch V, Hoffmann T, Schwab W, Suter-Grotemeyer M, Rentsch D, Truernit E, Ladwig F, Bleckmann A, Dresselhaus T, Hammes U. Amino Acid Export in Developing Arabidopsis Seeds Depends on UmamiT Facilitators. Curr Biol 2015; 25:3126-31. [DOI: 10.1016/j.cub.2015.10.038] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/12/2015] [Accepted: 10/15/2015] [Indexed: 12/26/2022]
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Affiliation(s)
- M. K. L. Strauss
- Department of Ecology, Evolution and BehaviorUniversity of Minnesota100 Ecology Bldg, 1987 Upper Buford Circle55108Saint PaulMNUSA
| | - M. Kilewo
- Tanzania National Parks, Ecology Department (Veterinary Unit)P.O. Box 3134ArushaTanzania
| | - D. Rentsch
- Frankfurt Zoological Society, Serengeti Community Outreach OfficeFort IkomaSerengetiTanzania
| | - C. Packer
- Department of Ecology, Evolution and BehaviorUniversity of Minnesota100 Ecology Bldg, 1987 Upper Buford Circle55108Saint PaulMNUSA
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21
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Batushansky A, Kirma M, Grillich N, Pham PA, Rentsch D, Galili G, Fernie AR, Fait A. The transporter GAT1 plays an important role in GABA-mediated carbon-nitrogen interactions in Arabidopsis. Front Plant Sci 2015; 6:785. [PMID: 26483804 PMCID: PMC4586413 DOI: 10.3389/fpls.2015.00785] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 09/11/2015] [Indexed: 05/22/2023]
Abstract
Glutamate derived γ-aminobutyric acid (GABA) is synthetized in the cytosol prior to delivery to the mitochondria where it is catabolized via the TCA cycle. GABA accumulates under various environmental conditions, but an increasing number of studies show its involvement at the crossroad between C and N metabolism. To assess the role of GABA in modulating cellular metabolism, we exposed seedlings of A. thaliana GABA transporter gat1 mutant to full nutrition medium and media deficient in C and N combined with feeding of different concentrations (0.5 and 1 mM) of exogenous GABA. GC-MS based metabolite profiling showed an expected effect of medium composition on the seedlings metabolism of mutant and wild type alike. That being said, a significant interaction between GAT1 deficiency and medium composition was determined with respect to magnitude of change in relative amino acid levels. The effect of exogenous GABA treatment on metabolism was contingent on both the medium and the genotype, leading for instance to a drop in asparagine under full nutrition and low C conditions and glucose under all tested media, but not to changes in GABA content. We additionally assessed the effect of GAT1 deficiency on the expression of glutamate metabolism related genes and genes involved in abiotic stress responses. These results suggest a role for GAT1 in GABA-mediated metabolic alterations in the context of the C-N equilibrium of plant cells.
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Affiliation(s)
- Albert Batushansky
- The Albert Katz International School for Desert Studies, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-GurionBeer Sheva, Israel
| | - Menny Kirma
- Department of Plant Science, Weizmann Institute of ScienceRehovot, Israel
| | - Nicole Grillich
- Central Metabolism Group, Willmitzer Department, Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Phuong A. Pham
- Central Metabolism Group, Willmitzer Department, Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Doris Rentsch
- Department of Biology, Institute of Plant Sciences, University of BernBern, Switzerland
| | - Gad Galili
- Department of Plant Science, Weizmann Institute of ScienceRehovot, Israel
| | - Alisdair R. Fernie
- Central Metabolism Group, Willmitzer Department, Max-Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany
| | - Aaron Fait
- The Albert Katz International School for Desert Studies, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-GurionBeer Sheva, Israel
- *Correspondence: Aaron Fait, Laboratory of Plant Metabolism, The French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, The Ben-Gurion University of the Negev, Villa 1, Midreshet Ben-Gurion 84990, Beer Sheva, Israel
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22
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Port A, Olszewski H, Walther U, Büttner A, Rentsch D. Nachweis von γ-Hydroxybuttersäure bei γ-Butyrolacton-Abhängigkeit. Rechtsmedizin (Berl) 2014. [DOI: 10.1007/s00194-014-0966-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Zanin L, Tomasi N, Wirdnam C, Meier S, Komarova NY, Mimmo T, Cesco S, Rentsch D, Pinton R. Isolation and functional characterization of a high affinity urea transporter from roots of Zea mays. BMC Plant Biol 2014; 14:222. [PMID: 25168432 PMCID: PMC4160556 DOI: 10.1186/s12870-014-0222-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [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: 05/12/2014] [Accepted: 08/06/2014] [Indexed: 05/24/2023]
Abstract
BACKGROUND Despite its extensive use as a nitrogen fertilizer, the role of urea as a directly accessible nitrogen source for crop plants is still poorly understood. So far, the physiological and molecular aspects of urea acquisition have been investigated only in few plant species highlighting the importance of a high-affinity transport system. With respect to maize, a worldwide-cultivated crop requiring high amounts of nitrogen fertilizer, the mechanisms involved in the transport of urea have not yet been identified. The aim of the present work was to characterize the high-affinity urea transport system in maize roots and to identify the high affinity urea transporter. RESULTS Kinetic characterization of urea uptake (<300 μM) demonstrated the presence in maize roots of a high-affinity and saturable transport system; this system is inducible by urea itself showing higher Vmax and Km upon induction. At molecular level, the ORF sequence coding for the urea transporter, ZmDUR3, was isolated and functionally characterized using different heterologous systems: a dur3 yeast mutant strain, tobacco protoplasts and a dur3 Arabidopsis mutant. The expression of the isolated sequence, ZmDUR3-ORF, in dur3 yeast mutant demonstrated the ability of the encoded protein to mediate urea uptake into cells. The subcellular targeting of DUR3/GFP fusion proteins in tobacco protoplasts gave results comparable to the localization of the orthologous transporters of Arabidopsis and rice, suggesting a partial localization at the plasma membrane. Moreover, the overexpression of ZmDUR3 in the atdur3-3 Arabidopsis mutant showed to complement the phenotype, since different ZmDUR3-overexpressing lines showed either comparable or enhanced 15[N]-urea influx than wild-type plants. These data provide a clear evidence in planta for a role of ZmDUR3 in urea acquisition from an extra-radical solution. CONCLUSIONS This work highlights the capability of maize plants to take up urea via an inducible and high-affinity transport system. ZmDUR3 is a high-affinity urea transporter mediating the uptake of this molecule into roots. Data may provide a key to better understand the mechanisms involved in urea acquisition and contribute to deepen the knowledge on the overall nitrogen-use efficiency in crop plants.
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Affiliation(s)
- Laura Zanin
- />Dipartimento di Scienze Agrarie e Ambientali, University of Udine, via delle Scienze 208, I-33100 Udine, Italy
| | - Nicola Tomasi
- />Dipartimento di Scienze Agrarie e Ambientali, University of Udine, via delle Scienze 208, I-33100 Udine, Italy
| | - Corina Wirdnam
- />Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Stefan Meier
- />Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Nataliya Y Komarova
- />Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Tanja Mimmo
- />Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, I-39100 Bolzano, Italy
| | - Stefano Cesco
- />Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, I-39100 Bolzano, Italy
| | - Doris Rentsch
- />Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Roberto Pinton
- />Dipartimento di Scienze Agrarie e Ambientali, University of Udine, via delle Scienze 208, I-33100 Udine, Italy
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24
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Affiliation(s)
- Susanne Schmidt
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Qld, 4072, Australia
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25
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Lonhienne TGA, Trusov Y, Young A, Rentsch D, Näsholm T, Schmidt S, Paungfoo-Lonhienne C. Effects of externally supplied protein on root morphology and biomass allocation in Arabidopsis. Sci Rep 2014; 4:5055. [PMID: 24852366 PMCID: PMC4031471 DOI: 10.1038/srep05055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 05/06/2014] [Indexed: 12/02/2022] Open
Abstract
Growth, morphogenesis and function of roots are influenced by the concentration and form of nutrients present in soils, including low molecular mass inorganic N (IN, ammonium, nitrate) and organic N (ON, e.g. amino acids). Proteins, ON of high molecular mass, are prevalent in soils but their possible effects on roots have received little attention. Here, we investigated how externally supplied protein of a size typical of soluble soil proteins influences root development of axenically grown Arabidopsis. Addition of low to intermediate concentrations of protein (bovine serum albumen, BSA) to IN-replete growth medium increased root dry weight, root length and thickness, and root hair length. Supply of higher BSA concentrations inhibited root development. These effects were independent of total N concentrations in the growth medium. The possible involvement of phytohormones was investigated using Arabidopsis with defective auxin (tir1-1 and axr2-1) and ethylene (ein2-1) responses. That no phenotype was observed suggests a signalling pathway is operating independent of auxin and ethylene responses. This study expands the knowledge on N form-explicit responses to demonstrate that ON of high molecular mass elicits specific responses.
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Affiliation(s)
- Thierry G. A. Lonhienne
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Yuri Trusov
- School of Agriculture and Food Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Anthony Young
- Plant Pathology Herbarium, Queensland Primary Industries and Fisheries, QLD, 4068, Australia
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, 3013 Bern, Switzerland
| | - Torgny Näsholm
- Department of Forest Ecology and Management, and Department of Forest Genetics and Plant Physiology, SLU, SE-901 83 Umeå, Sweden
| | - Susanne Schmidt
- School of Agriculture and Food Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia
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Léran S, Varala K, Boyer JC, Chiurazzi M, Crawford N, Daniel-Vedele F, David L, Dickstein R, Fernandez E, Forde B, Gassmann W, Geiger D, Gojon A, Gong JM, Halkier BA, Harris JM, Hedrich R, Limami AM, Rentsch D, Seo M, Tsay YF, Zhang M, Coruzzi G, Lacombe B. A unified nomenclature of NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family members in plants. Trends Plant Sci 2014; 19:5-9. [PMID: 24055139 DOI: 10.1016/j.tplants.2013.08.008] [Citation(s) in RCA: 358] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/16/2013] [Accepted: 08/22/2013] [Indexed: 05/18/2023]
Abstract
Members of the plant NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER (NRT1/PTR) family display protein sequence homology with the SLC15/PepT/PTR/POT family of peptide transporters in animals. In comparison to their animal and bacterial counterparts, these plant proteins transport a wide variety of substrates: nitrate, peptides, amino acids, dicarboxylates, glucosinolates, IAA, and ABA. The phylogenetic relationship of the members of the NRT1/PTR family in 31 fully sequenced plant genomes allowed the identification of unambiguous clades, defining eight subfamilies. The phylogenetic tree was used to determine a unified nomenclature of this family named NPF, for NRT1/PTR FAMILY. We propose that the members should be named accordingly: NPFX.Y, where X denotes the subfamily and Y the individual member within the species.
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Affiliation(s)
- Sophie Léran
- Biochimie et Physiologie Moléculaire des Plantes, UMR CNRS/INRA/UM2/SupAgro, Institut de Biologie Intégrative des Plantes 'Claude Grignon', Place Viala, 34060 Montpellier, France
| | - Kranthi Varala
- Department of Biology, Center for Genomics and Systems Biology, New York University, 12 Waverly Place, New York, NY 10003, USA
| | - Jean-Christophe Boyer
- Biochimie et Physiologie Moléculaire des Plantes, UMR CNRS/INRA/UM2/SupAgro, Institut de Biologie Intégrative des Plantes 'Claude Grignon', Place Viala, 34060 Montpellier, France
| | - Maurizio Chiurazzi
- Institute of Genetics and Biophysics 'Adriano Buzzati-Traverso', CNR, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Nigel Crawford
- Section of Cell and Developmental Biology, UC San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Françoise Daniel-Vedele
- INRA AgroParisTech, UMR1318 Institut Jean-Pierre Bourgin, RD10, 78026 Versailles Cedex, France
| | - Laure David
- INRA AgroParisTech, UMR1318 Institut Jean-Pierre Bourgin, RD10, 78026 Versailles Cedex, France
| | - Rebecca Dickstein
- Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, USA
| | - Emilio Fernandez
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa Baja E, Campus de Rabanales, E-14071, Córdoba, Spain
| | - Brian Forde
- Centre for Sustainable Agriculture, Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK
| | - Walter Gassmann
- Division of Plant Sciences, CS Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, MO 65211, USA
| | - Dietmar Geiger
- Universität Würzburg, Julius-von-Sachs-Institut für Biowissenschaften, Lehrstuhl für Molekulare Pflanzenphysiologie und Biophysik, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany
| | - Alain Gojon
- Biochimie et Physiologie Moléculaire des Plantes, UMR CNRS/INRA/UM2/SupAgro, Institut de Biologie Intégrative des Plantes 'Claude Grignon', Place Viala, 34060 Montpellier, France
| | - Ji-Ming Gong
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Barbara A Halkier
- DynaMo Centre of Excellence, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Jeanne M Harris
- Department of Plant Biology, 315 Jeffords Hall, 63 Carrigan Drive, University of Vermont, Burlington, VT 05405, USA
| | - Rainer Hedrich
- Universität Würzburg, Julius-von-Sachs-Institut für Biowissenschaften, Lehrstuhl für Molekulare Pflanzenphysiologie und Biophysik, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany
| | - Anis M Limami
- UMR 1345 Research Institute of Horticulture and Seeds (INRA, Agrocampus-Ouest, University of Angers), SFR 4207 Quasav, 2 Bd Lavoisier, 49045 Angers Cedex, France
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Mitsunori Seo
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan
| | - Yi-Fang Tsay
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Mingyong Zhang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Gloria Coruzzi
- Department of Biology, Center for Genomics and Systems Biology, New York University, 12 Waverly Place, New York, NY 10003, USA
| | - Benoît Lacombe
- Biochimie et Physiologie Moléculaire des Plantes, UMR CNRS/INRA/UM2/SupAgro, Institut de Biologie Intégrative des Plantes 'Claude Grignon', Place Viala, 34060 Montpellier, France.
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27
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Macêdo JP, Schmidt RS, Mäser P, Rentsch D, Vial HJ, Sigel E, Bütikofer P. Characterization of choline uptake in Trypanosoma brucei procyclic and bloodstream forms. Mol Biochem Parasitol 2013; 190:16-22. [PMID: 23747277 DOI: 10.1016/j.molbiopara.2013.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 05/27/2013] [Accepted: 05/28/2013] [Indexed: 10/26/2022]
Abstract
Choline is an essential nutrient for eukaryotic cells, where it is used as precursor for the synthesis of choline-containing phospholipids, such as phosphatidylcholine (PC). According to published data, Trypanosoma brucei parasites are unable to take up choline from the environment but instead use lyso-phosphatidylcholine as precursor for choline lipid synthesis. We now show that T. brucei procyclic forms in culture readily incorporate [(3)H]-labeled choline into PC, indicating that trypanosomes express a transporter for choline at the plasma membrane. Characterization of the transport system in T. brucei procyclic and bloodstream forms shows that uptake of choline is independent of sodium and potassium ions and occurs with a Km in the low micromolar range. In addition, we demonstrate that choline uptake can be blocked by the known choline transport inhibitor, hemicholinium-3, and by synthetic choline analogs that have been established as anti-malarials. Together, our results show that T. brucei parasites express an uptake system for choline and that exogenous choline is used for PC synthesis.
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Affiliation(s)
- Juan P Macêdo
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
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29
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Fang Z, Xia K, Yang X, Grotemeyer MS, Meier S, Rentsch D, Xu X, Zhang M. Altered expression of the PTR/NRT1 homologue OsPTR9 affects nitrogen utilization efficiency, growth and grain yield in rice. Plant Biotechnol J 2013; 11:446-58. [PMID: 23231455 DOI: 10.1111/pbi.12031] [Citation(s) in RCA: 57] [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] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 11/05/2012] [Accepted: 11/07/2012] [Indexed: 05/22/2023]
Abstract
The plant PTR/NRT1 (peptide transporter/nitrate transporter 1) gene family comprises di/tripeptide and low-affinity nitrate transporters; some members also recognize other substrates such as carboxylates, phytohormones (auxin and abscisic acid), or defence compounds (glucosinolates). Little is known about the members of this gene family in rice (Oryza sativa L.). Here, we report the influence of altered OsPTR9 expression on nitrogen utilization efficiency, growth, and grain yield. OsPTR9 expression is regulated by exogenous nitrogen and by the day-night cycle. Elevated expression of OsPTR9 in transgenic rice plants resulted in enhanced ammonium uptake, promotion of lateral root formation and increased grain yield. On the other hand, down-regulation of OsPTR9 in a T-DNA insertion line (osptr9) and in OsPTR9-RNAi rice plants had the opposite effect. These results suggest that OsPTR9 might hold potential for improving nitrogen utilization efficiency and grain yield in rice breeding.
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Affiliation(s)
- Zhongming Fang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
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30
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Pedrazzini E, Komarova NY, Rentsch D, Vitale A. Traffic Routes and Signals for the Tonoplast. Traffic 2013; 14:622-8. [DOI: 10.1111/tra.12051] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 01/23/2013] [Accepted: 01/28/2013] [Indexed: 01/17/2023]
Affiliation(s)
- Emanuela Pedrazzini
- Istituto di Biologia e Biotecnologia Agraria; Consiglio Nazionale delle Ricerche; Milano; Italy
| | | | - Doris Rentsch
- Institute of Plant Sciences; University of Bern; Bern; Switzerland
| | - Alessandro Vitale
- Istituto di Biologia e Biotecnologia Agraria; Consiglio Nazionale delle Ricerche; Milano; Italy
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31
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Yang SY, Grønlund M, Jakobsen I, Grotemeyer MS, Rentsch D, Miyao A, Hirochika H, Kumar CS, Sundaresan V, Salamin N, Catausan S, Mattes N, Heuer S, Paszkowski U. Nonredundant regulation of rice arbuscular mycorrhizal symbiosis by two members of the phosphate transporter1 gene family. Plant Cell 2012; 24:4236-51. [PMID: 23073651 PMCID: PMC3517247 DOI: 10.1105/tpc.112.104901] [Citation(s) in RCA: 205] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 09/11/2012] [Accepted: 09/24/2012] [Indexed: 05/18/2023]
Abstract
Pi acquisition of crops via arbuscular mycorrhizal (AM) symbiosis is becoming increasingly important due to limited high-grade rock Pi reserves and a demand for environmentally sustainable agriculture. Here, we show that 70% of the overall Pi acquired by rice (Oryza sativa) is delivered via the symbiotic route. To better understand this pathway, we combined genetic, molecular, and physiological approaches to determine the specific functions of two symbiosis-specific members of the PHOSPHATE TRANSPORTER1 (PHT1) gene family from rice, ORYsa;PHT1;11 (PT11) and ORYsa;PHT1;13 (PT13). The PT11 lineage of proteins from mono- and dicotyledons is most closely related to homologs from the ancient moss, indicating an early evolutionary origin. By contrast, PT13 arose in the Poaceae, suggesting that grasses acquired a particular strategy for the acquisition of symbiotic Pi. Surprisingly, mutations in either PT11 or PT13 affected the development of the symbiosis, demonstrating that both genes are important for AM symbiosis. For symbiotic Pi uptake, however, only PT11 is necessary and sufficient. Consequently, our results demonstrate that mycorrhizal rice depends on the AM symbiosis to satisfy its Pi demands, which is mediated by a single functional Pi transporter, PT11.
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Affiliation(s)
- Shu-Yi Yang
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Mette Grønlund
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-4000 Roskilde, Denmark
| | - Iver Jakobsen
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-4000 Roskilde, Denmark
| | | | - Doris Rentsch
- University of Bern, Institute of Plant Sciences, CH-3013, Switzerland
| | - Akio Miyao
- National Institute of Agrobiological Sciences, Agronomics Research Center, Tsukuba, Ibaraki 305-8602, Japan
| | - Hirohiko Hirochika
- National Institute of Agrobiological Sciences, Agronomics Research Center, Tsukuba, Ibaraki 305-8602, Japan
| | - Chellian Santhosh Kumar
- Department of Plant Biology and Plant Sciences, University of California, Davis, California 95616
| | - Venkatesan Sundaresan
- Department of Plant Biology and Plant Sciences, University of California, Davis, California 95616
| | - Nicolas Salamin
- Department of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Sheryl Catausan
- Plant Breeding, Genetics, and Biotechnology Division, International Rice Research Institute, Metro, Manila, 1301 Philippines
| | - Nicolas Mattes
- Plant Breeding, Genetics, and Biotechnology Division, International Rice Research Institute, Metro, Manila, 1301 Philippines
| | - Sigrid Heuer
- Plant Breeding, Genetics, and Biotechnology Division, International Rice Research Institute, Metro, Manila, 1301 Philippines
| | - Uta Paszkowski
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
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32
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Komarova NY, Meier S, Meier A, Grotemeyer MS, Rentsch D. Determinants for Arabidopsis peptide transporter targeting to the tonoplast or plasma membrane. Traffic 2012; 13:1090-105. [PMID: 22537078 DOI: 10.1111/j.1600-0854.2012.01370.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [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: 11/09/2011] [Revised: 04/19/2012] [Accepted: 04/26/2012] [Indexed: 12/29/2022]
Abstract
Di- and tripeptide transporters of the PTR/NRT1 (peptide transporter/nitrate transporter1)-family are localized either at the tonoplast (TP) or plasma membrane (PM). As limited information is available on structural determinants required for targeting of plant membrane proteins, we performed gene shuffling and domain swapping experiments of Arabidopsis PTRs. A 7 amino acid fragment of the hydrophilic N-terminal region of PTR2, PTR4 and PTR6 was required for TP localization and sufficient to redirect not only PM-localized PTR1 or PTR5, but also sucrose transporter SUC2 to the TP. Alanine scanning mutagenesis identified L(11) and I(12) of PTR2 to be essential for TP targeting, while only one acidic amino acid at position 5, 6 or 7 was required, revealing a dileucine (LL or LI) motif with at least one upstream acidic residue. Similar dileucine motifs could be identified in other plant TP transporters, indicating a broader role of this targeting motif in plants. Targeting to the PM required the loop between transmembrane domain 6 and 7 of PTR1 or PTR5. Deletion of either PM or TP targeting signals resulted in retention in internal membranes, indicating that PTR trafficking to these destination membranes requires distinct signals and is in both cases not by default.
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Affiliation(s)
- Nataliya Y Komarova
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland
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33
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Matam SK, Otal E, Aguirre M, Winkler A, Ulrich A, Rentsch D, Weidenkaff A, Ferri D. Thermal and chemical aging of model three-way catalyst Pd/Al2O3 and its impact on the conversion of CNG vehicle exhaust. Catal Today 2012. [DOI: 10.1016/j.cattod.2011.09.030] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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34
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Weber K, Sartori M, Cedraschi C, Genevay S, Canuto A, Rentsch D. [Interdisciplinary treatment of chronic low back pain: psychological aspects and personality traits]. Rev Med Suisse 2012; 8:368-370. [PMID: 22397067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Evidence on chronic low back pain treatments stresses the need for a multidimensional approach that aims a biopsychosocial rehabilitation. The caregiver team of the rheumatology division of the University Hospitals of Geneva has successfully applied this approach over the last years and this article emphasizes the value of a close collaboration with the division of liaison psychiatry. The use of cognitive-behavioral and psycho-educational techniques guaranties the definition of patient-centred and measurable treatment objectives. The inclusion of a psychotherapy group promotes free expression and sharing of psychological distress. Assessment of personality traits allows for considering the global nature of the patients rather than merely aiming the normalization of their deviant aspects.
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35
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Weichert A, Brinkmann C, Komarova NY, Dietrich D, Thor K, Meier S, Suter Grotemeyer M, Rentsch D. AtPTR4 and AtPTR6 are differentially expressed, tonoplast-localized members of the peptide transporter/nitrate transporter 1 (PTR/NRT1) family. Planta 2012; 235:311-323. [PMID: 21904872 DOI: 10.1007/s00425-011-1508-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/12/2011] [Indexed: 05/31/2023]
Abstract
Members of the peptide transporter/nitrate transporter 1 (PTR/NRT1) family in plants transport a variety of substrates like nitrate, di- and tripepetides, auxin and carboxylates. We isolated two members of this family from Arabidopsis, AtPTR4 and AtPTR6, which are highly homologous to the characterized di- and tripeptide transporters AtPTR1, AtPTR2 and AtPTR5. All known substrates of members of the PTR/NRT1 family were tested using heterologous expression in Saccharomyces cerevisiae mutants and oocytes of Xenopus laevis, but none could be identified as substrate of AtPTR4 or AtPTR6. AtPTR4 and AtPTR6 show distinct expression patterns, while AtPTR4 is expressed in the vasculature of the plants, AtPTR6 is highly expressed in pollen and during senescence. Phylogenetic analyses revealed that AtPTR2, 4 and 6 belong to one clade of subgoup II, whereas AtPTR1 and 5 are found in a second clade. Like AtPTR2, AtPTR4-GFP and AtPTR6-GFP fusion proteins are localized at the tonoplast. Vacuolar localization was corroborated by co-localization of AtPTR2-YFP with the tonoplast marker protein GFP-AtTIP2;1 and AtTIP1;1-GFP. This indicates that the two clades reflect different intracellular localization at the tonoplast (AtPTR2, 4, 6) and plasma membrane (AtPTR1, 5), respectively.
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Affiliation(s)
- Annett Weichert
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
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36
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Soper FM, Paungfoo-Lonhienne C, Brackin R, Rentsch D, Schmidt S, Robinson N. Arabidopsis and Lobelia anceps access small peptides as a nitrogen source for growth. Funct Plant Biol 2011; 38:788-796. [PMID: 32480936 DOI: 10.1071/fp11077] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Accepted: 07/21/2011] [Indexed: 05/09/2023]
Abstract
While importance of amino acids as a nitrogen source for plants is increasingly recognised, other organic N sources including small peptides have received less attention. We assessed the capacity of functionally different species, annual and nonmycorrhizal Arabidopsis thaliana (L.) Heynh. (Brassicaceae) and perennial Lobelia anceps L.f. (Campanulaceae), to acquire, metabolise and use small peptides as a N source independent of symbionts. Plants were grown axenically on media supplemented with small peptides (2-4 amino acids), amino acids or inorganic N. In A. thaliana, peptides of up to four amino acid residues sustained growth and supported up to 74% of the maximum biomass accumulation achieved with inorganic N. Peptides also supported growth of L. anceps, but to a lesser extent. Using metabolite analysis, a proportion of the peptides supplied in the medium were detected intact in root and shoot tissue together with their metabolic products. Nitrogen source preferences, growth responses and shoot-root biomass allocation were species-specific and suggest caution in the use of Arabidopsis as the sole plant model. In particular, glycine peptides of increasing length induced effects ranging from complete inhibition to marked stimulation of root growth. This study contributes to emerging evidence that plants can acquire and metabolise organic N beyond amino acids.
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Affiliation(s)
- Fiona M Soper
- School of Agriculture and Food Science, University of Queensland, St Lucia, Qld 4072, Australia
| | | | - Richard Brackin
- School of Agriculture and Food Science, University of Queensland, St Lucia, Qld 4072, Australia
| | - Doris Rentsch
- Molecular Plant Physiology, Institute of Plant Sciences, University of Bern, 3013 Bern, Switzerland
| | - Susanne Schmidt
- School of Agriculture and Food Science, University of Queensland, St Lucia, Qld 4072, Australia
| | - Nicole Robinson
- School of Agriculture and Food Science, University of Queensland, St Lucia, Qld 4072, Australia
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38
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Allaz AF, Cedraschi C, Rentsch D, Canuto A. [Chronic pain in elderly people: psychosocial dimension]. Rev Med Suisse 2011; 7:1407-1410. [PMID: 21815497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Chronic pain in elderly people requires to take into account somatic co-morbidities as well as its psychosocial dimensions. Chronic pain often represents a distress signal addressed to the environment and the care providers. Psychological suffering or mood disorders can be presented in the form of somatic complaints often associated with functional impairments, sometimes severe. Therapeutic care has to address functionality through an image-enhancing approach aiming to summon the patients' resources. The treatment of a concomitant depressive state necessitates a true commitment from the therapist. Its benefits are documented in elderly patients. Analgesic treatment as a whole will seek in particular to restore feelings of self-esteem and help the patient recover a good quality of life.
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Affiliation(s)
- A F Allaz
- Service de Médecine Interne de Réhabilitation Beau-Séjour, HUG, Genève.
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39
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Rentsch D, Allaz AF. [Chronic pain and depression]. Rev Med Suisse 2011; 7:1023-1024. [PMID: 21692320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Affiliation(s)
- D Rentsch
- Service de psychiatrie de liaison et intervention de crise, HUG, 1211 Genève 14.
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40
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Ramos MS, Abele R, Nagy R, Grotemeyer MS, Tampé R, Rentsch D, Martinoia E. Characterization of a transport activity for long-chain peptides in barley mesophyll vacuoles. J Exp Bot 2011; 62:2403-2410. [PMID: 21282327 DOI: 10.1093/jxb/erq397] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The plant vacuole is the largest compartment in a fully expanded plant cell. While only very limited metabolic activity can be observed within the vacuole, the majority of the hydrolytic activities, including proteolytic activities reside in this organelle. Since it is assumed that protein degradation by the proteasome results in the production of peptides with a size of 3-30 amino acids, we were interested to show whether the tonoplast exhibits a transport activity, which could deliver these peptides into the vacuole for final degradation. It is shown here that isolated barley mesophyll vacuoles take up peptides of 9-27 amino acids in a strictly ATP-dependent manner. Uptake is inhibited by vanadate, but not by NH(+)(4), while GTP could partially substitute for ATP. The apparent affinity for the 9 amino acid peptide was 15 μM, suggesting that peptides are efficiently transferred to the vacuole in vivo. Inhibition experiments showed that peptides with a chain length below 10 amino acids did not compete as efficiently as longer peptides for the uptake of the 9 amino acid peptide. Our results suggest that vacuoles contain at least one peptide transporter that belongs to the ABC-type transporters, which efficiently exports long-chain peptides from the cytosol into the vacuole for final degradation.
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Affiliation(s)
- Magali Schnell Ramos
- Institute of Plant Biology, University Zurich, Zollikerstrasse 107, 8008 Zurich, Switzerland
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41
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Abstract
The three proline transporters of Arabidopsis thaliana (AtProTs) transport the compatible solutes proline and glycine betaine and the stress-induced compound γ-aminobutyric acid when expressed in heterologous systems. The aim of the present study was to show transport and physiological relevance of these three AtProTs in planta. Using single, double, and triple knockout mutants and AtProT-overexpressing lines, proline content, growth on proline, transport of radiolabelled betaine, and expression of AtProT genes and enzymes of proline metabolism were analysed. AtProT2 was shown to facilitate uptake of L- and D-proline as well as [(14)C]glycine betaine in planta, indicating a role in the import of compatible solutes into the root. Toxic concentrations of L- and D-proline resulted in a drastic growth retardation of AtProT-overexpressing plants, demonstrating the need for a precise regulation of proline uptake and/or distribution. Furthermore evidence is provided that AtProT genes are highly expressed in tissues with elevated proline content--that is, pollen and leaf epidermis.
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Affiliation(s)
- Silke Lehmann
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Christophe Gumy
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Eva Blatter
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Silke Boeffel
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
| | - Wieland Fricke
- School of Biology and Environmental Science, UCD Science Centre West, University College Dublin, Belfield, Dublin 4, Ireland
| | - Doris Rentsch
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
- To whom correspondence should be addressed. E-mail:
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Inbar E, Canepa GE, Carrillo C, Glaser F, Suter Grotemeyer M, Rentsch D, Zilberstein D, Pereira CA. Lysine transporters in human trypanosomatid pathogens. Amino Acids 2010; 42:347-60. [PMID: 21170560 DOI: 10.1007/s00726-010-0812-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Accepted: 11/10/2010] [Indexed: 11/30/2022]
Abstract
In previous studies we characterized arginine transporter genes from Trypanosoma cruzi and Leishmania donovani, the etiological agents of chagas disease and kala azar, respectively, both fatal diseases in humans. Unlike arginine transporters in higher eukaryotes that transport also lysine, these parasite transporters translocate only arginine. This phenomenon prompted us to identify and characterize parasite lysine transporters. Here we demonstrate that LdAAP7 and TcAAP7 encode lysine-specific permeases in L. donovani and T. cruzi, respectively. These two lysine permeases are both members of the large amino acid/auxin permease family and share certain biochemical properties, such as specificity and Km. However, we evidence that LdAAP7 and TcAAP7 differ in their regulation and localization, such differences are likely a reflection of the dissimilar L. donovani and T. cruzi life cycles. Failed attempts to delete both alleles of LdAAP7 support the premise that this is an essential gene that encodes the only lysine permeases expressed in L. donovani promastigotes and T. cruzi epimastigotes, respectively.
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Affiliation(s)
- Ehud Inbar
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
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43
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Abstract
Plant growth, productivity, and seed yield depend on the efficient uptake, metabolism, and allocation of nutrients. Nitrogen is an essential macronutrient needed in high amounts. Plants have evolved efficient and selective transport systems for nitrogen uptake and transport within the plant to sustain development, growth, and finally reproduction. This review summarizes current knowledge on membrane proteins involved in transport of amino acids and peptides. A special emphasis was put on their function in planta. We focus on uptake of the organic nitrogen by the root, source-sink partitioning, and import into floral tissues and seeds.
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Affiliation(s)
- Mechthild Tegeder
- School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA.
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Hammes UZ, Meier S, Dietrich D, Ward JM, Rentsch D. Functional properties of the Arabidopsis peptide transporters AtPTR1 and AtPTR5. J Biol Chem 2010; 285:39710-7. [PMID: 20937801 DOI: 10.1074/jbc.m110.141457] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Arabidopsis di- and tripeptide transporters AtPTR1 and AtPTR5 were expressed in Xenopus laevis oocytes, and their selectivity and kinetic properties were determined by voltage clamping and by radioactive uptake. Dipeptide transport by AtPTR1 and AtPTR5 was found to be electrogenic and dependent on protons but not sodium. In the absence of dipeptides, both transporters showed proton-dependent leak currents that were inhibited by Phe-Ala (AtPTR5) and Phe-Ala, Trp-Ala, and Phe-Phe (AtPTR1). Phe-Ala was shown to reduce leak currents by binding to the substrate-binding site with a high apparent affinity. Inhibition of leak currents was only observed when the aromatic amino acids were present at the N-terminal position. AtPTR1 and AtPTR5 transport activity was voltage-dependent, and currents increased supralinearly with more negative membrane potentials and did not saturate. The voltage dependence of the apparent affinities differed between Ala-Ala, Ala-Lys, and Ala-Asp and was not conserved between the two transporters. The apparent affinity of AtPTR1 for these dipeptides was pH-dependent and decreased with decreasing proton concentration. In contrast to most proton-coupled transporters characterized so far, -I(max) increased at high pH, indicating that regulation of the transporter by pH overrides the importance of protons as co-substrate.
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Affiliation(s)
- Ulrich Z Hammes
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
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45
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Abstract
Proline fulfils diverse functions in plants. As amino acid it is a structural component of proteins, but it also plays a role as compatible solute under environmental stress conditions. Proline metabolism involves several subcellular compartments and contributes to the redox balance of the cell. Proline synthesis has been associated with tissues undergoing rapid cell divisions, such as shoot apical meristems, and appears to be involved in floral transition and embryo development. High levels of proline can be found in pollen and seeds, where it serves as compatible solute, protecting cellular structures during dehydration. The proline concentrations of cells, tissues and plant organs are regulated by the interplay of biosynthesis, degradation and intra- as well as intercellular transport processes. Among the proline transport proteins characterized so far, both general amino acid permeases and selective compatible solute transporters were identified, reflecting the versatile role of proline under stress and non-stress situations. The review summarizes our current knowledge on proline metabolism and transport in view of plant development, discussing regulatory aspects such as the influence of metabolites and hormones. Additional information from animals, fungi and bacteria is included, showing similarities and differences to proline metabolism and transport in plants.
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Affiliation(s)
- Silke Lehmann
- Institute of Plant Sciences, University of Bern, Switzerland.
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46
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Paungfoo-Lonhienne C, Rentsch D, Robatzek S, Webb RI, Sagulenko E, Näsholm T, Schmidt S, Lonhienne TGA. Turning the table: plants consume microbes as a source of nutrients. PLoS One 2010; 5:e11915. [PMID: 20689833 PMCID: PMC2912860 DOI: 10.1371/journal.pone.0011915] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 07/07/2010] [Indexed: 11/21/2022] Open
Abstract
Interactions between plants and microbes in soil, the final frontier of ecology, determine the availability of nutrients to plants and thereby primary production of terrestrial ecosystems. Nutrient cycling in soils is considered a battle between autotrophs and heterotrophs in which the latter usually outcompete the former, although recent studies have questioned the unconditional reign of microbes on nutrient cycles and the plants' dependence on microbes for breakdown of organic matter. Here we present evidence indicative of a more active role of plants in nutrient cycling than currently considered. Using fluorescent-labeled non-pathogenic and non-symbiotic strains of a bacterium and a fungus (Escherichia coli and Saccharomyces cerevisiae, respectively), we demonstrate that microbes enter root cells and are subsequently digested to release nitrogen that is used in shoots. Extensive modifications of root cell walls, as substantiated by cell wall outgrowth and induction of genes encoding cell wall synthesizing, loosening and degrading enzymes, may facilitate the uptake of microbes into root cells. Our study provides further evidence that the autotrophy of plants has a heterotrophic constituent which could explain the presence of root-inhabiting microbes of unknown ecological function. Our discovery has implications for soil ecology and applications including future sustainable agriculture with efficient nutrient cycles.
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Lehmann S, Funck D, Szabados L, Rentsch D. Proline metabolism and transport in plant development. Amino Acids 2010; 39:949-62. [DOI: 10.1007/s00726-010-0525-3] [Citation(s) in RCA: 225] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 02/10/2010] [Indexed: 01/21/2023]
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48
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Smaga D, Cheseaux N, Forster A, Colombo S, Rentsch D, de Tonnac N. [Hypnosis and anxiety problems]. Rev Med Suisse 2010; 6:330-333. [PMID: 20229722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This article describes how hypnosis can be used as an efficient technique in treating patients with anxious disorders. Hypnosis can be used to achieve a better control of the anxious symptoms through relaxation. It allows the patient to anticipate the anxiety triggering events. This technique also allows the patient to mentalise and integrate traumatic events, therefore helping him to prevent the post-traumatic anxious symptoms.
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Affiliation(s)
- D Smaga
- HUG, Département de psychiatrie, Avenue Krieg 15, 1208 Genève.
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49
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Rentsch D, Piguet V, Cedraschi C, Desmeules J, Luthy C, Andreoli A, Allaz AF. [Chronic pain and depression]. Rev Med Suisse 2009; 5:1364-1369. [PMID: 19626761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Chronic pain and depression are frequently associated. Links between them are numerous and well documented. It is known for example that depression is associated with a greater number and higher intensity of pain symptoms. Similarly the presence of pain complicates the diagnostic evaluation and aggravates the prognosis of depression. The question of the causality link has no clear answer. Taking care of these patients implies to acknowledge the different aspects of their suffering in a holistic bio-psycho-social model. Treatment or medication, for instance antidepressants, should be a post-scriptum to the construction of a therapeutic relationship.
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Affiliation(s)
- D Rentsch
- Service de psychiatrie de liaison et d'intervention de crise, Département de psychiatrie adulte, HUG, Genève.
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50
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Darlyuk I, Goldman A, Roberts SC, Ullman B, Rentsch D, Zilberstein D. Arginine homeostasis and transport in the human pathogen Leishmania donovani. J Biol Chem 2009; 284:19800-7. [PMID: 19439418 DOI: 10.1074/jbc.m901066200] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Arginine is an essential amino acid for the human pathogen Leishmania but not to its host. Thus, the mechanism by which this protozoan parasite regulates cellular homeostasis of arginine is critical for its survival and virulence. In a previous study, we cloned and functionally characterized a high affinity arginine-specific transporter, LdAAP3, from Leishmania donovani. In this investigation, we have characterized the relationship between arginine transport via LdAAP3 and amino acid availability. Starving promastigotes for amino acids decreased the cellular level of most amino acids including arginine but also increased the abundance of both LdAAP3 mRNA and protein and up-regulated arginine transport activity. Genetic obliteration of the polyamine biosynthesis pathway for which arginine is the sole precursor caused a significant decrease in the rate of arginine transport. Cumulatively, we established that LdAAP3 expression and activity changed whenever the cellular level of arginine changed. Our findings have led to the hypothesis that L. donovani promastigotes have a signaling pathway that senses cellular concentrations of arginine and subsequently activates a mechanism that regulates LdAAP3 expression and activity. Interestingly, this response of LdAAP3 to amino acid availability in L. donovani is identical to that of the mammalian cation amino acid transporter 1. Thus, we conjecture that Leishmania mimics the host response to amino acid availability to improve virulence.
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Affiliation(s)
- Ilona Darlyuk
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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