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Sato N, Khoa HV, Mikami K. Heat stress memory differentially regulates the expression of nitrogen transporter genes in the filamentous red alga ' Bangia' sp. ESS1. FRONTIERS IN PLANT SCIENCE 2024; 15:1331496. [PMID: 38375079 PMCID: PMC10875135 DOI: 10.3389/fpls.2024.1331496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 01/22/2024] [Indexed: 02/21/2024]
Abstract
Introduction To withstand high temperatures that would be lethal to a plant in the naïve state, land plants must establish heat stress memory. The acquisition of heat stress tolerance via heat stress memory in algae has only been observed in the red alga 'Bangia' sp. ESS1. Methods In this study, we further evaluated the intrinsic ability of this alga to establish heat stress memory by monitoring hydrogen peroxide (H2O2) production and examining the relationship between heat stress memory and the expression of genes encoding nitrogen transporters, since heat stress generally reduces nitrogen absorption. Next, genes encoding nitrogen transporters were selected from our unpublished transcriptome data of 'Bangia' sp. ESS1. Results We observed a reduction in H2O2 content when heat stress memory was established in the alga. In addition, six ammonium transporter genes, a single-copy nitrate transporter gene and two urea transporter genes were identified. Two of these nitrogen transporter genes were induced by heat stress but not by heat stress memory, two genes showed heat stress memory-dependent expression, and one gene was induced by both treatments. Heat stress memory therefore differentially regulated the expression of the nitrogen transporter genes by reducing heat stress-inducible gene expression and inducing heat stress memory-dependent gene expression. Discussion These findings point to the functional diversity of nitrogen transporter genes, which play different roles under various heat stress conditions. The characteristic effects of heat stress memory on the expression of individual nitrogen transporter genes might represent an indispensable strategy for reducing the threshold of sensitivity to recurrent high-temperature conditions and for maintaining nitrogen absorption under such conditions in 'Bangia' sp. ESS1.
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Affiliation(s)
- Natsumi Sato
- School of Food Industrial Sciences, Miyagi University, Sendai, Japan
| | - Ho Viet Khoa
- Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Japan
| | - Koji Mikami
- School of Food Industrial Sciences, Miyagi University, Sendai, Japan
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2
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Maniero RA, Koltun A, Vitti M, Factor BG, de Setta N, Câmara AS, Lima JE, Figueira A. Identification and functional characterization of the sugarcane ( Saccharum spp.) AMT2-type ammonium transporter ScAMT3;3 revealed a presumed role in shoot ammonium remobilization. FRONTIERS IN PLANT SCIENCE 2023; 14:1299025. [PMID: 38098795 PMCID: PMC10720369 DOI: 10.3389/fpls.2023.1299025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 11/13/2023] [Indexed: 12/17/2023]
Abstract
Sugarcane (Saccharum spp.) is an important crop for sugar and bioethanol production worldwide. To maintain and increase sugarcane yields in marginal areas, the use of nitrogen (N) fertilizers is essential, but N overuse may result in the leaching of reactive N to the natural environment. Despite the importance of N in sugarcane production, little is known about the molecular mechanisms involved in N homeostasis in this crop, particularly regarding ammonium (NH4 +), the sugarcane's preferred source of N. Here, using a sugarcane bacterial artificial chromosome (BAC) library and a series of in silico analyses, we identified an AMMONIUM TRANSPORTER (AMT) from the AMT2 subfamily, sugarcane AMMONIUM TRANSPORTER 3;3 (ScAMT3;3), which is constitutively and highly expressed in young and mature leaves. To characterize its biochemical function, we ectopically expressed ScAMT3;3 in heterologous systems (Saccharomyces cerevisiae and Arabidopsis thaliana). The complementation of triple mep mutant yeast demonstrated that ScAMT3;3 is functional for NH3/H+ cotransport at high availability of NH4 + and under physiological pH conditions. The ectopic expression of ScAMT3;3 in the Arabidopsis quadruple AMT knockout mutant restored the transport capacity of 15N-NH4 + in roots and plant growth under specific N availability conditions, confirming the role of ScAMT3;3 in NH4 + transport in planta. Our results indicate that ScAMT3;3 belongs to the low-affinity transport system (Km 270.9 µM; Vmax 209.3 µmol g-1 root DW h-1). We were able to infer that ScAMT3;3 plays a presumed role in NH4 + source-sink remobilization in the shoots via phloem loading. These findings help to shed light on the functionality of a novel AMT2-type protein and provide bases for future research focusing on the improvement of sugarcane yield and N use efficiency.
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Affiliation(s)
- Rodolfo A. Maniero
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Alessandra Koltun
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Marielle Vitti
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Bruna G. Factor
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Nathalia de Setta
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, São Bernardo do Campo, SP, Brazil
| | - Amanda S. Câmara
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Joni E. Lima
- Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Antonio Figueira
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
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Nazir F, Mahajan M, Khatoon S, Albaqami M, Ashfaque F, Chhillar H, Chopra P, Khan MIR. Sustaining nitrogen dynamics: A critical aspect for improving salt tolerance in plants. FRONTIERS IN PLANT SCIENCE 2023; 14:1087946. [PMID: 36909406 PMCID: PMC9996754 DOI: 10.3389/fpls.2023.1087946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
In the current changing environment, salt stress has become a major concern for plant growth and food production worldwide. Understanding the mechanisms of how plants function in saline environments is critical for initiating efforts to mitigate the detrimental effects of salt stress. Agricultural productivity is linked to nutrient availability, and it is expected that the judicious metabolism of mineral nutrients has a positive impact on alleviating salt-induced losses in crop plants. Nitrogen (N) is a macronutrient that contributes significantly to sustainable agriculture by maintaining productivity and plant growth in both optimal and stressful environments. Significant progress has been made in comprehending the fundamental physiological and molecular mechanisms associated with N-mediated plant responses to salt stress. This review provided an (a) overview of N-sensing, transportation, and assimilation in plants; (b) assess the salt stress-mediated regulation of N dynamics and nitrogen use- efficiency; (c) critically appraise the role of N in plants exposed to salt stress. Furthermore, the existing but less explored crosstalk between N and phytohormones has been discussed that may be utilized to gain a better understanding of plant adaptive responses to salt stress. In addition, the shade of a small beam of light on the manipulation of N dynamics through genetic engineering with an aim of developing salt-tolerant plants is also highlighted.
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Affiliation(s)
- Faroza Nazir
- Department of Botany, Jamia Hamdard, New Delhi, India
| | - Moksh Mahajan
- Department of Botany, Jamia Hamdard, New Delhi, India
| | | | - Mohammed Albaqami
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Farha Ashfaque
- Department of Botany, Aligarh Muslim University, Aligarh, India
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Zhong Y, Tian J, Li X, Liao H. Cooperative interactions between nitrogen fixation and phosphorus nutrition in legumes. THE NEW PHYTOLOGIST 2023; 237:734-745. [PMID: 36324147 DOI: 10.1111/nph.18593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
Legumes such as soybean are considered important crops as they provide proteins and oils for humans and livestock around the world. Different from other crops, leguminous crops accumulate nitrogen (N) for plant growth through symbiotic nitrogen fixation (SNF) in coordination with rhizobia. A number of studies have shown that efficient SNF requires the cooperation of other nutrients, especially phosphorus (P), a nutrient deficient in most soils. During the last decades, great progress has been made in understanding the molecular mechanisms underlying the interactions between SNF and P nutrition, specifically through the identification of transporters involved in P transport to nodules and bacteroids, signal transduction, and regulation of P homeostasis in nodules. These studies revealed a distinct N-P interaction in leguminous crops, which is characterized by specific signaling cross talk between P and SNF. This review aimed to present an updated picture of the cross talk between N fixation and P nutrition in legumes, focusing on soybean as a model crop, and Medicago truncatula and Lotus japonicus as model plants. We also discuss the possibilities for enhancing SNF through improving P nutrition, which are important for high and sustainable production of leguminous crops.
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Affiliation(s)
- Yongjia Zhong
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jiang Tian
- Root Biology Center, South China Agricultural University, Guangzhou, 510642, China
| | - Xinxin Li
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Hong Liao
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
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Koltun A, Maniero RA, Vitti M, de Setta N, Giehl RFH, Lima JE, Figueira A. Functional characterization of the sugarcane ( Saccharum spp.) ammonium transporter AMT2;1 suggests a role in ammonium root-to-shoot translocation. FRONTIERS IN PLANT SCIENCE 2022; 13:1039041. [PMID: 36466275 PMCID: PMC9716016 DOI: 10.3389/fpls.2022.1039041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/31/2022] [Indexed: 06/17/2023]
Abstract
AMMONIUM TRANSPORTER/METHYLAMMONIUM PERMEASE/RHESUS (AMT) family members transport ammonium across membranes in all life domains. Plant AMTs can be categorized into AMT1 and AMT2 subfamilies. Functional studies of AMTs, particularly AMT1-type, have been conducted using model plants but little is known about the function of AMTs from crops. Sugarcane (Saccharum spp.) is a major bioenergy crop that requires heavy nitrogen fertilization but depends on a low carbon-footprint for competitive sustainability. Here, we identified and functionally characterized sugarcane ScAMT2;1 by complementing ammonium uptake-defective mutants of Saccharomyces cerevisiae and Arabidopsis thaliana. Reporter gene driven by the ScAMT2;1 promoter in A. thaliana revealed preferential expression in the shoot vasculature and root endodermis/pericycle according to nitrogen availability and source. Arabidopsis quadruple mutant plants expressing ScAMT2;1 driven by the CaMV35S promoter or by a sugarcane endogenous promoter produced significantly more biomass than mutant plants when grown in NH4 + and showed more 15N-ammonium uptake by roots and nitrogen translocation to shoots. In A. thaliana, ScAMT2;1 displayed a Km of 90.17 µM and Vmax of 338.99 µmoles h-1 g-1 root DW. Altogether, our results suggest that ScAMT2;1 is a functional high-affinity ammonium transporter that might contribute to ammonium uptake and presumably to root-to-shoot translocation under high NH4 + conditions.
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Affiliation(s)
- Alessandra Koltun
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Rodolfo A. Maniero
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Marielle Vitti
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Nathalia de Setta
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, São Bernardo do Campo, SP, Brazil
- Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ricardo F. H. Giehl
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Joni E. Lima
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
- Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Antonio Figueira
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
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Genome-Wide Identification and Expression Analysis of AMT Gene Family in Apple (Malus domestica Borkh.). HORTICULTURAE 2022. [DOI: 10.3390/horticulturae8050457] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ammonium is one of the prevalent nitrogen sources for growth and development of higher plants. Ammonium acquisition from soil is facilitated by ammonium transporters (AMTs), which are plasma membrane proteins that exclusively transport ammonium/ammonia. However, the functional characteristics and molecular mechanisms of AMTs in apple remain unclear. In this work, 15 putative AMT genes were identified and classified into four clusters (AMT1–AMT4) in apple. According to expression analysis, these AMTs had varying expressions in roots, leaves, stems, flowers and fruits. Some of them were strongly affected by diurnal cycles. AMT genes showed multiple transcript patterns to N regimes and were quite responsive to osmotic stress. In addition, phosphorylation analysis revealed that there were some conserved phosphorylation residues within the C-terminal of AMT proteins. Furthermore, detailed research was conducted on AMT1;2 functioning by heterologous expression in yeast. The present study is expected to provide basic bioinformatic information and expression profiles for the apple AMT family and to lay a basis for exploring the functional roles and regulation mechanisms of AMTs in apple.
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Wang Y, Xuan YM, Wang SM, Fan DM, Wang XC, Zheng XQ. Genome-wide identification, characterization, and expression analysis of the ammonium transporter gene family in tea plants (Camellia sinensis L.). PHYSIOLOGIA PLANTARUM 2022; 174:e13646. [PMID: 35129836 DOI: 10.1111/ppl.13646] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 01/30/2022] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
As a preferred nitrogen form, ammonium (NH4 + ) transport via specific transporters is particularly important for the growth and development of tea plants (Camellia sinensis L.). However, our understanding of the functions of the AMT family in tea plants is limited. We identified and named 16 putative AMT genes according to phylogenetic analysis. All CsAMT genes were divided into three groups, distributed on 12 chromosomes with only one segmental duplication repetition. The CsAMT genes showed different expression levels in different organs, and most of them were expressed mainly in the apical buds and roots. Complementation analysis of yeast mutants showed that CsAMTs restored the uptake of NH4 + . This study provides insights into the genome-wide distribution and spatial expression of AMT genes in tea plants.
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Affiliation(s)
- Yu Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Yi-Min Xuan
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Shu-Mao Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Dong-Mei Fan
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xiao-Chang Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xin-Qiang Zheng
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
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8
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Ma Y, Chen R. Nitrogen and Phosphorus Signaling and Transport During Legume-Rhizobium Symbiosis. FRONTIERS IN PLANT SCIENCE 2021; 12:683601. [PMID: 34239527 PMCID: PMC8258413 DOI: 10.3389/fpls.2021.683601] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 05/25/2021] [Indexed: 05/11/2023]
Abstract
Nitrogen (N) and phosphorus (P) are the two predominant mineral elements, which are not only essential for plant growth and development in general but also play a key role in symbiotic N fixation in legumes. Legume plants have evolved complex signaling networks to respond to both external and internal levels of these macronutrients to optimize symbiotic N fixation in nodules. Inorganic phosphate (Pi) and nitrate (NO3 -) are the two major forms of P and N elements utilized by plants, respectively. Pi starvation and NO3 - application both reduce symbiotic N fixation via similar changes in the nodule gene expression and invoke local and long-distance, systemic responses, of which N-compound feedback regulation of rhizobial nitrogenase activity appears to operate under both conditions. Most of the N and P signaling and transport processes have been investigated in model organisms, such as Medicago truncatula, Lotus japonicus, Glycine max, Phaseolus vulgaris, Arabidopsis thaliana, Oryza sativa, etc. We attempted to discuss some of these processes wherever appropriate, to serve as references for a better understanding of the N and P signaling and transport during symbiosis.
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Affiliation(s)
- Yanlin Ma
- MOE Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
- School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Rujin Chen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
- School of Life Sciences, Lanzhou University, Lanzhou, China
- *Correspondence: Rujin Chen,
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Cloning and Functional Determination of Ammonium Transporter PpeAMT3;4 in Peach. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2147367. [PMID: 33344631 PMCID: PMC7732375 DOI: 10.1155/2020/2147367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/15/2020] [Accepted: 11/20/2020] [Indexed: 01/29/2023]
Abstract
Ammonium (NH4+) plays key roles in plant growth, development, fruit quality, and yield. In plants, NH4+ uptake and transport are facilitated by NH4+ transporters (AMT). However, molecular mechanisms and physiological functions of type-II AMT (AMT2) transporters in fruit trees are still unclear, especially in peach. In this study, we cloned and characterized an AMT2 family gene from peach, PpeAMT3;4, and determined its function in yeast mutant. Expression analysis showed that PpeAMT3;4 was majorly expressed in peach roots and significantly decreased by NH4+ excess but had no response to NH4+ deficiency. Functional determination and 15nitrogen-labeled NH4+ uptake assay in yeast cells implied that PpeAMT3;4 was a typical high-affinity transporter, with a Km value of 86.3 μM, that can uptake external NH4+ in yeast cells. This study provides gene resources to uncover the biological function of AMT2 transporters and reveals molecular basis for NH4+ uptake and nitrogen (N) nutrition mechanisms in fruit trees.
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Combined Transcriptome and Proteome Analysis of Masson Pine ( Pinus massoniana Lamb.) Seedling Root in Response to Nitrate and Ammonium Supplementations. Int J Mol Sci 2020; 21:ijms21207548. [PMID: 33066140 PMCID: PMC7593940 DOI: 10.3390/ijms21207548] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 11/25/2022] Open
Abstract
Nitrogen (N) is an essential nutrient for plant growth and development. Plant species respond to N fluctuations and N sources, i.e., ammonium or nitrate, differently. Masson pine (Pinus massoniana Lamb.) is one of the pioneer plants in the southern forests of China. It shows better growth when grown in medium containing ammonium as compared to nitrate. In this study, we had grown masson pine seedlings in medium containing ammonium, nitrate, and a mixture of both, and performed comparative transcriptome and proteome analyses to observe the differential signatures. Our transcriptome and proteome resulted in the identification of 1593 and 71 differentially expressed genes and proteins, respectively. Overall, the masson pine roots had better performance when fed with a mixture of ammonium and nitrate. The transcriptomic and proteomics results combined with the root morphological responses suggest that when ammonium is supplied as a sole N-source to masson pine seedlings, the expression of ammonium transporters and other non-specific NH4+-channels increased, resulting in higher NH4+ concentrations. This stimulates lateral roots branching as evidenced from increased number of root tips. We discussed the root performance in association with ethylene responsive transcription factors, WRKYs, and MADS-box transcription factors. The differential analysis data suggest that the adaptability of roots to ammonium is possibly through the promotion of TCA cycle, owing to the higher expression of malate synthase and malate dehydrogenase. Masson pine seedlings managed the increased NH4+ influx by rerouting N resources to asparagine production. Additionally, flavonoid biosynthesis and flavone and flavonol biosynthesis pathways were differentially regulated in response to increased ammonium influx. Finally, changes in the glutathione s-transferase genes suggested the role of glutathione cycle in scavenging the possible stress induced by excess NH4+. These results demonstrate that masson pine shows increased growth when grown under ammonium by increased N assimilation. Furthermore, it can tolerate high NH4+ content by involving asparagine biosynthesis and glutathione cycle.
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Hao DL, Zhou JY, Yang SY, Qi W, Yang KJ, Su YH. Function and Regulation of Ammonium Transporters in Plants. Int J Mol Sci 2020; 21:E3557. [PMID: 32443561 PMCID: PMC7279009 DOI: 10.3390/ijms21103557] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023] Open
Abstract
Ammonium transporter (AMT)-mediated acquisition of ammonium nitrogen from soils is essential for the nitrogen demand of plants, especially for those plants growing in flooded or acidic soils where ammonium is dominant. Recent advances show that AMTs additionally participate in many other physiological processes such as transporting ammonium from symbiotic fungi to plants, transporting ammonium from roots to shoots, transferring ammonium in leaves and reproductive organs, or facilitating resistance to plant diseases via ammonium transport. Besides being a transporter, several AMTs are required for the root development upon ammonium exposure. To avoid the adverse effects of inadequate or excessive intake of ammonium nitrogen on plant growth and development, activities of AMTs are fine-tuned not only at the transcriptional level by the participation of at least four transcription factors, but also at protein level by phosphorylation, pH, endocytosis, and heterotrimerization. Despite these progresses, it is worth noting that stronger growth inhibition, not facilitation, unfortunately occurs when AMT overexpression lines are exposed to optimal or slightly excessive ammonium. This implies that a long road remains towards overcoming potential limiting factors and achieving AMT-facilitated yield increase to accomplish the goal of persistent yield increase under the present high nitrogen input mode in agriculture.
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Affiliation(s)
- Dong-Li Hao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; (D.-L.H.); (J.-Y.Z.); (S.-Y.Y.)
| | - Jin-Yan Zhou
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; (D.-L.H.); (J.-Y.Z.); (S.-Y.Y.)
| | - Shun-Ying Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; (D.-L.H.); (J.-Y.Z.); (S.-Y.Y.)
| | - Wei Qi
- College of Resources and Environment, Shandong Agricultural University, Taian 271018, China;
| | - Ke-Jun Yang
- Agro-Tech Extension and Service Center, Zhucheng 262200, China;
| | - Yan-Hua Su
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; (D.-L.H.); (J.-Y.Z.); (S.-Y.Y.)
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Sun YC, Sheng S, Fan TF, Liu L, Ke J, Wang DB, Hua JP, Liu LH, Cao FQ. Molecular identification and functional characterization of GhAMT1.3 in ammonium transport with a high affinity from cotton (Gossypium hirsutum L.). PHYSIOLOGIA PLANTARUM 2019; 167:217-231. [PMID: 30467856 DOI: 10.1111/ppl.12882] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/10/2018] [Accepted: 11/19/2018] [Indexed: 06/09/2023]
Abstract
Ammonium (NH4 + ) represents a primary nitrogen source for many plants, its effective transport into and between tissues and further assimilation in cells determine greatly plant nitrogen use efficiency. However, biological components involved in NH4 + movement in woody plants are unclear. Here, we report kinetic evidence for cotton NH4 + uptake and molecular identification of certain NH4 + transporters (AMTs) from cotton (Gossypium hirustum). A substrate-influx assay using 15 N-isotope revealed that cotton possessed a high-affinity transport system with a Km of 58 μM for NH4 + . Sequence analysis showed that GhAMT1.1-1.3 encoded respectively a membrane protein containing 485, 509 or 499 amino acids. Heterologous functionality test demonstrated that GhAMT1.1-1.3 expression mediated NH4 + permeation across the plasma membrane (PM) of yeast and/or Arabidopsis qko-mutant cells, allowing a growth restoration of both mutants on NH4 + . Quantitative PCR measurement showed that GhAMT1.3 was expressed in roots and leaves and markedly up-regulated by N-starvation, repressed by NH4 + resupply and regulated diurnally and age-dependently, suggesting that GhAMT1.3 should be a N-responsive gene. Importantly, GhAMT1.3 expression in Arabidopsis improved plant growth on NH4 + and enhanced total nitrogen accumulation (∼50% more), conforming with the observation of 2-fold more NH4 + absorption by GhAMT1.3-transformed qko plant roots during a 1-h root influx period. Together with its targeting to the PM and saturated transport kinetics with a Km of 72 μM for NH4 + , GhAMT1.3 is suggested to be a high-affinity NH4 + permease that may play a significant role in cotton NH4 + acquisition and utilization, adding a new member in the plant AMT family.
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Affiliation(s)
- Yi-Chen Sun
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Song Sheng
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Teng-Fei Fan
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing, 400716, China
| | - Lu Liu
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Jie Ke
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Dai-Bin Wang
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing, 400716, China
| | - Jin-Ping Hua
- College of Agronomy and Biotechnology, Beijing Key Lab of Crop Genetic Improvement, China Agricultural University, Beijing, 100193, China
| | - Lai-Hua Liu
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Feng-Qiu Cao
- Shanghai Center for Plant Stress Biology, Institute of Plant Physiology Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
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Li FW, Brouwer P, Carretero-Paulet L, Cheng S, de Vries J, Delaux PM, Eily A, Koppers N, Kuo LY, Li Z, Simenc M, Small I, Wafula E, Angarita S, Barker MS, Bräutigam A, dePamphilis C, Gould S, Hosmani PS, Huang YM, Huettel B, Kato Y, Liu X, Maere S, McDowell R, Mueller LA, Nierop KGJ, Rensing SA, Robison T, Rothfels CJ, Sigel EM, Song Y, Timilsena PR, Van de Peer Y, Wang H, Wilhelmsson PKI, Wolf PG, Xu X, Der JP, Schluepmann H, Wong GKS, Pryer KM. Fern genomes elucidate land plant evolution and cyanobacterial symbioses. NATURE PLANTS 2018; 4:460-472. [PMID: 29967517 PMCID: PMC6786969 DOI: 10.1038/s41477-018-0188-8] [Citation(s) in RCA: 250] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 05/24/2018] [Indexed: 05/18/2023]
Abstract
Ferns are the closest sister group to all seed plants, yet little is known about their genomes other than that they are generally colossal. Here, we report on the genomes of Azolla filiculoides and Salvinia cucullata (Salviniales) and present evidence for episodic whole-genome duplication in ferns-one at the base of 'core leptosporangiates' and one specific to Azolla. One fern-specific gene that we identified, recently shown to confer high insect resistance, seems to have been derived from bacteria through horizontal gene transfer. Azolla coexists in a unique symbiosis with N2-fixing cyanobacteria, and we demonstrate a clear pattern of cospeciation between the two partners. Furthermore, the Azolla genome lacks genes that are common to arbuscular mycorrhizal and root nodule symbioses, and we identify several putative transporter genes specific to Azolla-cyanobacterial symbiosis. These genomic resources will help in exploring the biotechnological potential of Azolla and address fundamental questions in the evolution of plant life.
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Affiliation(s)
- Fay-Wei Li
- Boyce Thompson Institute, Ithaca, NY, USA.
- Plant Biology Section, Cornell University, Ithaca, NY, USA.
| | - Paul Brouwer
- Molecular Plant Physiology Department, Utrecht University, Utrecht, the Netherlands
| | - Lorenzo Carretero-Paulet
- Bioinformatics Institute Ghent and Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Shifeng Cheng
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
| | - Jan de Vries
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Pierre-Marc Delaux
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, Castanet Tolosan, France
| | - Ariana Eily
- Department of Biology, Duke University, Durham, NC, USA
| | - Nils Koppers
- Department of Plant Biochemistry, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Dusseldorf, Germany
| | | | - Zheng Li
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | - Mathew Simenc
- Department of Biological Science, California State University, Fullerton, CA, USA
| | - Ian Small
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Eric Wafula
- Department of Biology, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA
| | - Stephany Angarita
- Department of Biological Science, California State University, Fullerton, CA, USA
| | - Michael S Barker
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | | | - Claude dePamphilis
- Department of Biology, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA
| | - Sven Gould
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf, Dusseldorf, Germany
| | | | | | - Bruno Huettel
- Max Planck Genome Centre Cologne, Max Planck Institute for Plant Breeding, Cologne, Germany
| | - Yoichiro Kato
- Institute for Sustainable Agro-ecosystem Services, University of Tokyo, Tokyo, Japan
| | - Xin Liu
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
| | - Steven Maere
- Bioinformatics Institute Ghent and Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Rose McDowell
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | | | - Klaas G J Nierop
- Geolab, Faculty of Geosciences, Utrecht University, Utrecht, the Netherlands
| | | | - Tanner Robison
- Department of Biology, Utah State University, Logan, UT, USA
| | - Carl J Rothfels
- University Herbarium and Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - Erin M Sigel
- Department of Biology, University of Louisiana, Lafayette, LA, USA
| | - Yue Song
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
| | - Prakash R Timilsena
- Department of Biology, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA
| | - Yves Van de Peer
- Bioinformatics Institute Ghent and Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Hongli Wang
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
| | | | - Paul G Wolf
- Department of Biology, Utah State University, Logan, UT, USA
| | - Xun Xu
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
| | - Joshua P Der
- Department of Biological Science, California State University, Fullerton, CA, USA
| | | | - Gane K-S Wong
- BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China
- Department of Biological Sciences, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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14
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Zhu Y, Hao Y, Liu H, Sun G, Chen R, Song S. Identification and characterization of two ammonium transporter genes in flowering Chinese cabbage ( Brassica campestris). PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2018; 35:59-70. [PMID: 31275038 PMCID: PMC6543737 DOI: 10.5511/plantbiotechnology.18.0202a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/02/2018] [Indexed: 06/09/2023]
Abstract
Ammonium transporters (AMTs), which include AMT1 and AMT2 subfamilies, have been identified and partially characterized in many plants. In this study, two AMT2-type genes from Brassica campestris, namely BcAMT2 and BcAMT2like, were identified and characterized. BcAMT2 and BcAMT2like are 2666 bp and 2952 bp, encode proteins of 490 and 489 amino acids, respectively, and contain five exons and four introns. Transient expression of these proteins labelled with green fluorescence protein in onion epidermal cells indicated that both are located on the plasma membrane. When expressing BcAMT2 or BcAMT2like, the mutant yeast strain 31019b could grow on medium containing 2 mM ammonium as the only nitrogen source when expressing BcAMT2 or BcAMT2like, indicating that both are functional AMT genes. Quantitative PCR results showed that BcAMT2 and BcAMT2like were expressed in all tissues, but they displayed different expression patterns in the reproductive stages. BcAMT2s transcript levels in leaves were positively correlated with ammonium concentration and external pH. Moreover, the expression BcAMT2s responded to diurnal change. Furthermore, the uncharged form of ammonium, i.e., ammonia, might also be transported by BcAMT2s. These results provide new insights into the molecular mechanisms underlying ammonium absorption and transportation by the AMT2 subfamily in B. campestris.
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Affiliation(s)
- Yunna Zhu
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
| | - Yanwei Hao
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
| | - Houcheng Liu
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
| | - Guangwen Sun
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
| | - Riyuan Chen
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
| | - Shiwei Song
- College of Horticulture, South China Agricultural University, 510642, Guangzhou, People’s Republic of China
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Molecular cloning and expression analysis of ammonium transporters in tea plants (Camellia sinensis (L.) O. Kuntze) under different nitrogen treatments. Gene 2018. [PMID: 29535022 DOI: 10.1016/j.gene.2018.03.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ammonium is a major inorganic nitrogen source for tea plant growth and is mainly taken up and transported by ammonium transporters (AMTs). Here, we analyzed the NH4+ uptake kinetics of three tea cultivars, Longjing43 (LJ43), Zhongcha108 (ZC108) and Zhongcha302 (ZC302). The results revealed that ZC302 had a higher NH4+ uptake efficiency than the other two cultivars. The full CDS sequences of three Camellia sinensis ammonium transporter (CsAMT) genes, i.e., CsAMT1.1, CsAMT1.2 and CsAMT3.1, were cloned. Analysis of tissue-specific expression showed that CsAMT1.2 followed a root-specific expression pattern, while transcripts of CsAMT1.1 and CsAMT3.1 were mainly accumulated in leaves. The temporal course experiment on gene expression levels showed CsAMT1.1 and CsAMT3.1 followed a reciprocal expression pattern in leaves as CsAMT1.1 was up-regulated by a short time (2 h, 6 h) nitrogen (N) supply both in the leaves and buds of LJ43 and ZC108; and the expression of CsAMT3.1 in leaves was increased by a long time (72 h) N supply, particularly in ZC302. Therefore, we inferred that CsAMT1.1 and CsAMT3.1 might play important roles in photorespiratory ammonium metabolism. The expression of CsAMT1.2 was extremely high in roots and can be greatly induced by N over a short period of time, especially in ZC302; thus, we concluded CsAMT1.2 might play an important role in ammonium uptake from soils in tea plant roots.
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16
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Fan TF, Cheng XY, Shi DX, He MJ, Yang C, Liu L, Li CJ, Sun YC, Chen YY, Xu C, Zhang L, Liu LH. Molecular identification of tobacco NtAMT1.3 that mediated ammonium root-influx with high affinity and improved plant growth on ammonium when overexpressed in Arabidopsis and tobacco. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 264:102-111. [PMID: 28969790 DOI: 10.1016/j.plantsci.2017.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 06/07/2023]
Abstract
Although biological functions of ammonium (NH4+) transporters (AMTs) have been intensively studied in many plant species, little is known about molecular bases responsible for NH4+ movement in tobacco. Here, we reported the identification and functional characterization of a putative NH4+ transporter NtAMT1.3 from tobacco (Nicotiana tabacum). Analysis in silico showed that NtAMT1.3 encoded an integral membrane protein containing 464 amino acid residues and exhibiting 10 predicted transmembrane α-helices. Heterologous functionality study demonstrated that NtAMT1.3 expression facilitated NH4+ entry across plasma membrane of NH4+-uptake defective yeast and Arabidopsis qko mutant, allowing a restored growth of both yeast and Arabidopsis mutant on low NH4+. qPCR assay revealed that NtAMT1.3 was expressed in both roots and leaves and significantly up-regulated by nitrogen starvation and resupply of its putative substrate NH4+ and even nitrate, suggesting that NtAMT1.3 should represent a nitrogen-responsive gene. Critically, constitutive overexpression of NtAMT1.3 in tobacco per se improved obviously the growth of transgenic plants on NH4+ and enhanced leaf nitrogen (15% more) accumulation, consistent with observation of 35% more NH4+ uptake by the roots of transgenic lines in 20min root-influx test. Together with data showing its plasma membrane localization and saturated transport nature with Km of about 50μM for NH4+, we suggest that NtAMT1.3 acts an active NH4+ transporter that plays a significant role in NH4+ acquisition and utilization in tobacco.
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Affiliation(s)
- Teng-Fei Fan
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Xiao-Yuan Cheng
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Dong-Xue Shi
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Ming-Jie He
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; College of Agriculture Sciences, Hunan Agricultural University, Changsha 410128, China
| | - Chao Yang
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Lu Liu
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Chang-Jun Li
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Yi-Chen Sun
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Yi-Yin Chen
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Chen Xu
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Lei Zhang
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Lai-Hua Liu
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
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17
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Li T, Liao K, Xu X, Gao Y, Wang Z, Zhu X, Jia B, Xuan Y. Wheat Ammonium Transporter (AMT) Gene Family: Diversity and Possible Role in Host-Pathogen Interaction with Stem Rust. FRONTIERS IN PLANT SCIENCE 2017; 8:1637. [PMID: 28979288 PMCID: PMC5611643 DOI: 10.3389/fpls.2017.01637] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/06/2017] [Indexed: 05/03/2023]
Abstract
Ammonium transporter (AMT) proteins have been reported in many plants, but no comprehensive analysis was performed in wheat. In this study, we identified 23 AMT members (hereafter TaAMTs) using a protein homology search in wheat genome. Tissue-specific expression analysis showed that TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a were relatively more highly expressed in comparison with other TaAMTs. TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a-GFP were localized in the plasma membrane in tobacco leaves, and TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a successfully complemented a yeast 31019b strain in which ammonium uptake was deficient. In addition, the expression of TaAMT1;1b in an Arabidopsis AMT quadruple mutant (qko) successfully restored [Formula: see text] uptake ability. Resupply of [Formula: see text] rapidly increased cellular [Formula: see text] contents and suppressed expression of TaAMT1;3a, but not of TaAMT;1;1a and TaAMT1;1b expressions. Expression of TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a was not changed in leaves after [Formula: see text] resupply. In contrast, nitrogen (N) deprivation induced TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a gene expressions in the roots and leaves. Expression analysis in the leaves of the stem rust-susceptible wheat line "Little Club" and the rust-tolerant strain "Mini 2761" revealed that TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a were specifically induced in the former but not in the latter. Rust-susceptible wheat plants grown under N-free conditions exhibited a lower disease index than plants grown with [Formula: see text] as the sole N source in the medium after infection with Puccinia graminis f. sp. tritici, suggesting that [Formula: see text] and its transport may facilitate the infection of wheat stem rust disease. Our findings may be important for understanding the potential function TaAMTs in wheat plants.
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Affiliation(s)
- Tianya Li
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Kai Liao
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Xiaofeng Xu
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Yue Gao
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Ziyuan Wang
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Xiaofeng Zhu
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
| | - Baolei Jia
- Department of Life Sciences, Chung-Ang UniversitySeoul, South Korea
| | - Yuanhu Xuan
- College of Plant Protection, Shenyang Agricultural UniversityShenyang, China
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18
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Li H, Yang QS, Liu W, Lin J, Chang YH. The AMT1 family genes from Malus robusta display differential transcription features and ammonium transport abilities. Mol Biol Rep 2017; 44:379-390. [PMID: 28840433 DOI: 10.1007/s11033-017-4119-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Accepted: 08/19/2017] [Indexed: 11/28/2022]
Abstract
Ammonium is an important nitrogen sources for plant growth. In this study, we report on the gene characterization of the ammonium transporter AMT1 subfamily in the apple rootstock Malus robusta Rehd. Thirteen AMT genes were comprehensively evaluated from the apple genome (version 1.0). Then the gene features and expression patterns of five AMT1 members from M. robusta were analyzed. These genes fell into four clusters in the AMT phylogenetic tree: clade I (MrAMT1;1 and MrAMT1;3), clade II (MrAMT1;4), clade III (MrAMT1;2), and clade IV (MrAMT1;5). All the AMT1s, apart from MrAMT1;4, were expressed in vegetative organs and strongly responded to nitrogen concentration changes. For example, MrAMT1;2 and MrAMT1;3 had high transcript accumulation levels in the leaves and roots, respectively. Finally, the functions of these AMT1s were studied in detail by heterologous expression in yeast. These genes allowed strain 31019b to assimilate nitrogen, but their 15NH4+ uptake kinetics varied. These results revealed the functional roles of AMT1 during ammonium absorption in the AMT-defective mutant yeast system.
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Affiliation(s)
- Hui Li
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing, China
| | - Qing-Song Yang
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing, China
| | - Wei Liu
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing, China
| | - Jing Lin
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing, China
| | - You-Hong Chang
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing, China.
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19
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Murray JD, Liu CW, Chen Y, Miller AJ. Nitrogen sensing in legumes. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1919-1926. [PMID: 27927992 DOI: 10.1093/jxb/erw405] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Legumes fix atmospheric nitrogen (N) in a symbiotic relationship with bacteria. For this reason, although legume crops can be low yielding and less profitable when compared with cereals, they are frequently included in crop rotations. Grain legumes form only a minor part of most human diets, and legume crops are greatly underutilized. Food security and soil fertility could be significantly improved by greater grain legume usage and increased improvement of a range of grain legumes. One limitation for the use of legumes as a source of N input into agricultural systems is the fact that the formation of N-fixing nodules is suppressed when soils are replete with n. In this review, we report what is known about this process and how soil N supply might be sensed and feed back to regulate nodulation.
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Affiliation(s)
- Jeremy D Murray
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Cheng-Wu Liu
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Yi Chen
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Anthony J Miller
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
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20
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Li H, Han JL, Chang YH, Lin J, Yang QS. Gene characterization and transcription analysis of two new ammonium transporters in pear rootstock (Pyrus betulaefolia). JOURNAL OF PLANT RESEARCH 2016; 129:737-748. [PMID: 26943161 DOI: 10.1007/s10265-016-0799-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 10/29/2015] [Indexed: 05/07/2023]
Abstract
Ammonium is the primarily nitrogen source for plant growth, but the molecular basis of ammonium acquisition in fruit species remains poorly understood. In this study, we report on the characterization of two new ammonium transporters (AMT) in the perennial tree Pyrus betulaefolia. In silico analyses and yeast complementation assays revealed that both PbAMT1;3 and PbAMT1;5 can be classified in the AMT1 sub-family. The specific expression of PbAMT1;3 in roots and of PbAMT1;5 in leaves indicates that they have diverse functions in ammonium uptake or transport in P. betulaefolia. Their expression was strongly influenced by ammonium availability. In addition, the transcript level of PbAMT1;5 was significantly affected by the diurnal cycle and senescence hormones. They conferred the ability to uptake nitrogen to the yeast strain 31019b; however, the (15)NH4 (+) uptake kinetics of PbAMT1;3 were different from those of PbAMT1;5. Indeed, PbAMT1;3 had a higher affinity for (15)NH4 (+), and pH changes were associated with this substrates' transport in yeast. The present study provides basic gene features and transcriptional information for the two new members of the AMT1 sub-family in P. betulaefolia and will aid in decoding the precise roles of AMTs in P. betulaefolia physiology.
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Affiliation(s)
- Hui Li
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, No. 50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Jin-Long Han
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, No. 50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - You-Hong Chang
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, No. 50 Zhongling Street, Nanjing, 210014, Jiangsu, China.
| | - Jing Lin
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, No. 50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Qing-Song Yang
- Institute of Horticulture, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, No. 50 Zhongling Street, Nanjing, 210014, Jiangsu, China
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21
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Deepa P, Yusuf A. Influence of different host associations on glutamine synthetase activity and ammonium transporter in Santalumalbum L. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2016; 22:331-340. [PMID: 27729719 PMCID: PMC5039156 DOI: 10.1007/s12298-016-0368-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/24/2016] [Accepted: 07/31/2016] [Indexed: 06/06/2023]
Abstract
The present study was aimed at understanding the role of different hosts in ammonium transporter1;2 expressions and glutamine synthetase(GS) activity and their effects on the growth parameters in the sandal. Sandal plant associated with leguminous host expressed better growth parameters. GS activity of leguminous hosts alone and in host associated sandals was analyzed using GS transferase assay. Highest GS activity was expressed in Mimosa pudica-sandal association compared to other leguminous and non-leguminous host associations. The association of N2 fixing host with sandal enhanced C and N levels in order to maintain the C/N value. The role of ammonium transporters in N nutrition of sandal-host association was elucidated by cloning AMT1;2 from the leaves, haustoria and roots of host associated sandal and quantifying the relative expression by the [Formula: see text] method. SaAMT1;2 was strongly up-regulated in leaves, roots and haustoria of leguminous host associated sandal compared to non-leguminous host associations. The relative increase in SaAMT1;2 expressions and up-regulated GS activity positively affected the growth parameters in sandal when associated with leguminous hosts.
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Affiliation(s)
- P. Deepa
- Interuniversity Centre for Plant Biotechnology, Department of Botany, University of Calicut, Kerala, 673635 India
| | - A. Yusuf
- Interuniversity Centre for Plant Biotechnology, Department of Botany, University of Calicut, Kerala, 673635 India
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22
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Role of Arbuscular Mycorrhizal Fungi in the Nitrogen Uptake of Plants: Current Knowledge and Research Gaps. AGRONOMY-BASEL 2015. [DOI: 10.3390/agronomy5040587] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Vigna subterranea ammonium transporter gene ( VsAMT1): Some bioinformatics insights. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2015; 8:88-93. [PMID: 28352577 PMCID: PMC4980749 DOI: 10.1016/j.btre.2015.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 09/22/2015] [Accepted: 10/08/2015] [Indexed: 12/11/2022]
Abstract
Ammonium transporters (AMTs) play a role in the uptake of ammonium, the form in which nitrogen is preferentially absorbed by plants. Vigna subterranea (VsAMT1) and Solanum tuberosum (StAMT1) AMT1s were characterized using molecular biology and bioinformatics methods. AMT1-specific primers were designed and used to amplify the AMT1 internal regions. Nucleotide sequencing, alignment and phylogenetic analysis assigned VsAMT1 and StAMT1 to the AMT1 family. The deduced amino acid sequences showed that VsAMT1 is 92% and 89% similar to Phaseolus vulgaris PvAMT1.1 and Glycine max AMT1 respectively, while StAMT1 is 92% similar to Solanum lycopersicum LeAMT1.1, and correspond to the 5th–10th trans-membrane domains. Residues VsAMT1 D23 and StAMT1 D15 are predicted to be essential for ammonium transport, while mutations of VsAMT1 W1A-L and S87A and StAMT1 S76A may further enhance ammonium transport. In addition to nitrogen uptake from the roots, VsAMT1 may also contribute to interactions with rhizobia.
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D'Apuzzo E, Valkov VT, Parlati A, Omrane S, Barbulova A, Sainz MM, Lentini M, Esposito S, Rogato A, Chiurazzi M. PII Overexpression in Lotus japonicus Affects Nodule Activity in Permissive Low-Nitrogen Conditions and Increases Nodule Numbers in High Nitrogen Treated Plants. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:432-42. [PMID: 25390190 DOI: 10.1094/mpmi-09-14-0285-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We report here the first characterization of a GLNB1 gene coding for the PII protein in leguminous plants. The main purpose of this work was the investigation of the possible roles played by this multifunctional protein in nodulation pathways. The Lotus japonicus LjGLB1 gene shows a significant transcriptional regulation during the light-dark cycle and different nitrogen availability, conditions that strongly affect nodule formation, development, and functioning. We also report analysis of the spatial profile of expression of LjGLB1 in root and nodule tissues and of the protein's subcellular localization. Transgenic L. japonicus lines overexpressing the PII protein were obtained and tested for the analysis of the symbiotic responses in different conditions. The uncoupling of PII from its native regulation affects nitrogenase activity and nodule polyamine content. Furthermore, our results suggest the involvement of PII in the signaling of the nitrogen nutritional status affecting the legumes' predisposition for nodule formation.
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Affiliation(s)
- Enrica D'Apuzzo
- 1 Institute of Biosciences and Bioresources, CNR, Via P. Castellino 111, Napoli, Italy
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25
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Yang S, Hao D, Cong Y, Jin M, Su Y. The rice OsAMT1;1 is a proton-independent feedback regulated ammonium transporter. PLANT CELL REPORTS 2015; 34:321-30. [PMID: 25433856 DOI: 10.1007/s00299-014-1709-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 10/20/2014] [Accepted: 11/19/2014] [Indexed: 05/22/2023]
Abstract
Functional identification of a relatively lower affinity ammonium transporter, OsAMT1;1, which is a proton-independent feedback regulated ammonium transporter in rice. Rice genome contains at least 12 ammonium transporters, though their functionality has not been clearly resolved. Here, we demonstrate the functional properties of OsAMT1;1 applying functional complementation and (15)NH4 (+) uptake determination in yeast cells in combination with electrophysiological measurements in Xenopus oocytes. Our results show that OsAMT1;1 is a NH4 (+) transporter with relatively lower affinity to NH4 (+) (110-129 μM in oocytes and yeast cells, respectively). Under our experimental conditions, OsAMT1;1-mediated NH4 (+) uptake or current is not significantly modulated by extra- or intracellular pH gradient, suggesting that this transporter probably functions as a NH4 (+) uniporter. Inhibition of yeast growth or currents elicited from oocytes by ammonium assimilation inhibitor L-methionine sulfoximine indicates that NH4 (+) transport by OsAMT1;1 is likely feedback regulated by accumulation of the substrate. In addition, effects of phosphorylation inhibitors imply that NH4 (+) uptake by OsAMT1;1 is also modulated by tyrosine-specific protein kinase or calcium-regulated serine/threonine-specific protein phosphatase involved phosphorylation processes.
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Affiliation(s)
- Shunying Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71, East Beijing Road, Nanjing, 210008, China
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Reddy MM, Ulaganathan K. Nitrogen Nutrition, Its Regulation and Biotechnological Approaches to Improve Crop Productivity. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/ajps.2015.618275] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Straub D, Ludewig U, Neuhäuser B. A nitrogen-dependent switch in the high affinity ammonium transport in Medicago truncatula. PLANT MOLECULAR BIOLOGY 2014; 86:485-94. [PMID: 25164101 DOI: 10.1007/s11103-014-0243-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 08/18/2014] [Indexed: 05/26/2023]
Abstract
Ammonium transporters (AMTs) are crucial for the high affinity primary uptake and translocation of ammonium in plants. In the model legume Medicago truncatula, the genomic set of AMT-type ammonium transporters comprises eight members. Only four genes were abundantly expressed in young seedlings, both in roots and shoots. While the expression of all AMTs in the shoot was not affected by the nitrogen availability, the dominating MtAMT1;1 gene was repressed by nitrogen in roots, despite that cellular nitrogen concentrations were far above deficiency levels. A contrasting de-repression by nitrogen was observed for MtAMT1;4 and MtAMT2;1, which were both expressed at intermediate level. Weak expression was found for MtAMT1;2 and MtAMT2;3, while the other AMTs were not detected in young seedlings. When expressed from their endogenous promoters, translational fusion proteins of MtAMT1;1 and MtAMT2;1 with green fluorescent protein were co-localized in the plasma membrane of rhizodermal cells, but also detected in cortical root layers. Both transporter proteins similarly functionally complemented a yeast strain that is deficient in high affinity ammonium transport, both at acidic and neutral pH. The uptake into yeast mediated by these transporters saturated with Km AMT1;1 = 89 µM and Km AMT2;1 = 123 µM, respectively. When expressed in oocytes, MtAMT1;1 mediated much larger (15)N-ammonium uptake than MtAMT2;1, but NH4 (+) currents were only recorded for MtAMT1;1. These currents saturated with a voltage-dependent Km = 90 µM at -80 mV. The cellular localization and regulation of the AMTs suggests that MtAMT1;1 encodes the major high affinity ammonium transporter gene in low nitrogen grown young M. truncatula roots and despite the similar localization and substrate affinity, MtAMT2;1 appears functionally distinct and more important at higher nitrogen supply.
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Affiliation(s)
- Daniel Straub
- Institute of Crop Science, Nutritional Crop Physiology, University of Hohenheim, Fruwirthstr. 20, 70593, Stuttgart, Germany
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Offre P, Kerou M, Spang A, Schleper C. Variability of the transporter gene complement in ammonia-oxidizing archaea. Trends Microbiol 2014; 22:665-75. [PMID: 25169021 DOI: 10.1016/j.tim.2014.07.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Revised: 07/17/2014] [Accepted: 07/30/2014] [Indexed: 12/19/2022]
Abstract
Ammonia-oxidizing archaea (AOA) are a widespread and abundant component of microbial communities in many different ecosystems. The extent of physiological differences between individual AOA is, however, unknown. Here, we compare the transporter gene complements of six AOA, from four different environments and two major clades, to assess their potential for substrate uptake and efflux. Each of the corresponding AOA genomes encode a unique set of transporters and although the composition of AOA transporter complements follows a phylogenetic pattern, few transporter families are conserved in all investigated genomes. A comparison of ammonia transporters encoded by archaeal and bacterial ammonia oxidizers highlights the variance among AOA lineages as well as their distinction from the ammonia-oxidizing bacteria, and suggests differential ecological adaptations.
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Affiliation(s)
- Pierre Offre
- University of Vienna, Department of Ecogenomics and Systems Biology, Archaea Biology and Ecogenomics Division, Althanstrasse 14, A-1090 Wien, Austria.
| | - Melina Kerou
- University of Vienna, Department of Ecogenomics and Systems Biology, Archaea Biology and Ecogenomics Division, Althanstrasse 14, A-1090 Wien, Austria
| | - Anja Spang
- Uppsala University, Department of Cell and Molecular Biology, Science for Life Laboratory, Box 596, SE-75123, Uppsala, Sweden
| | - Christa Schleper
- University of Vienna, Department of Ecogenomics and Systems Biology, Archaea Biology and Ecogenomics Division, Althanstrasse 14, A-1090 Wien, Austria.
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Chiasson DM, Loughlin PC, Mazurkiewicz D, Mohammadidehcheshmeh M, Fedorova EE, Okamoto M, McLean E, Glass ADM, Smith SE, Bisseling T, Tyerman SD, Day DA, Kaiser BN. Soybean SAT1 (Symbiotic Ammonium Transporter 1) encodes a bHLH transcription factor involved in nodule growth and NH4+ transport. Proc Natl Acad Sci U S A 2014; 111:4814-9. [PMID: 24707045 PMCID: PMC3977234 DOI: 10.1073/pnas.1312801111] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Glycine max symbiotic ammonium transporter 1 was first documented as a putative ammonium (NH4(+)) channel localized to the symbiosome membrane of soybean root nodules. We show that Glycine max symbiotic ammonium transporter 1 is actually a membrane-localized basic helix-loop-helix (bHLH) DNA-binding transcription factor now renamed Glycine max bHLH membrane 1 (GmbHLHm1). In yeast, GmbHLHm1 enters the nucleus and transcriptionally activates a unique plasma membrane NH4(+) channel Saccharomyces cerevisiae ammonium facilitator 1. Ammonium facilitator 1 homologs are present in soybean and other plant species, where they often share chromosomal microsynteny with bHLHm1 loci. GmbHLHm1 is important to the soybean rhizobium symbiosis because loss of activity results in a reduction of nodule fitness and growth. Transcriptional changes in nodules highlight downstream signaling pathways involving circadian clock regulation, nutrient transport, hormone signaling, and cell wall modification. Collectively, these results show that GmbHLHm1 influences nodule development and activity and is linked to a novel mechanism for NH4(+) transport common to both yeast and plants.
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Affiliation(s)
- David M. Chiasson
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
| | - Patrick C. Loughlin
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
- School of Biological Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Danielle Mazurkiewicz
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
| | | | - Elena E. Fedorova
- Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University, 6703 HA, Wageningen, The Netherlands
| | - Mamoru Okamoto
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
| | - Elizabeth McLean
- School of Plant Biology, The University of Western Australia, Crawley, Perth, WA 6009, Australia
| | - Anthony D. M. Glass
- Department of Botany, The University of British Columbia, Vancouver, BC, Canada V6T 1Z4
| | - Sally E. Smith
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
| | - Ton Bisseling
- Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University, 6703 HA, Wageningen, The Netherlands
- College of Science, King Saud University, Riyadh 11451, Saudi Arabia; and
| | - Stephen D. Tyerman
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
| | - David A. Day
- School of Biological Sciences, Flinders University, Adelaide, SA 5001, Australia
| | - Brent N. Kaiser
- School of Agriculture Food and Wine, The University of Adelaide, Adelaide, SA 5050, Australia
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von Wittgenstein NJJB, Le CH, Hawkins BJ, Ehlting J. Evolutionary classification of ammonium, nitrate, and peptide transporters in land plants. BMC Evol Biol 2014; 14:11. [PMID: 24438197 PMCID: PMC3922906 DOI: 10.1186/1471-2148-14-11] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 12/30/2013] [Indexed: 01/15/2023] Open
Abstract
Background Nitrogen uptake, reallocation within the plant, and between subcellular compartments involves ammonium, nitrate and peptide transporters. Ammonium transporters are separated into two distinct families (AMT1 and AMT2), each comprised of five members on average in angiosperms. Nitrate transporters also form two discrete families (NRT1 and NRT2), with angiosperms having four NRT2s, on average. NRT1s share an evolutionary history with peptide transporters (PTRs). The NRT1/PTR family in land plants usually has more than 50 members and contains also members with distinct activities, such as glucosinolate and abscisic acid transport. Results Phylogenetic reconstructions of each family across 20 land plant species with available genome sequences were supplemented with subcellular localization and transmembrane topology predictions. This revealed that both AMT families diverged prior to the separation of bryophytes and vascular plants forming two distinct clans, designated as supergroups, each. Ten supergroups were identified for the NRT1/PTR family. It is apparent that nitrate and peptide transport within the NRT1/PTR family is polyphyletic, that is, nitrate and/or peptide transport likely evolved multiple times within land plants. The NRT2 family separated into two distinct clans early in vascular plant evolution. Subsequent duplications occurring prior to the eudicot/monocot separation led to the existence of two AMT1, six AMT2, 31 NRT1/PTR, and two NRT2 clans, designated as groups. Conclusion Phylogenetic separation of groups suggests functional divergence within the angiosperms for each family. Distinct groups within the NRT1/PTR family appear to separate peptide and nitrate transport activities as well as other activities contained within the family, for example nitrite transport. Conversely, distinct activities, such as abscisic acid and glucosinolate transport, appear to have recently evolved from nitrate transporters.
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Affiliation(s)
| | | | | | - Jürgen Ehlting
- Centre for Forest Biology & Department of Biology, University of Victoria, PO Box 1700 STN CSC, Victoria, BC V8W 2Y2, Canada.
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31
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Bu Y, Sun B, Zhou A, Zhang X, Lee I, Liu S. Identification and characterization of a PutAMT1;1 gene from Puccinellia tenuiflora. PLoS One 2013; 8:e83111. [PMID: 24340088 PMCID: PMC3858356 DOI: 10.1371/journal.pone.0083111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 10/31/2013] [Indexed: 11/19/2022] Open
Abstract
Nitrogen is one of the most important limiting factors for plant growth. However, as ammonium is readily converted into ammonia (NH3) when soil pH rises above 8.0, this activity depletes the availability of ammonium (NH4(+)) in alkaline soils, consequently preventing the growth of most plant species. The perennial wild grass Puccinellia tenuiflora is one of a few plants able to grow in soils with extremely high salt and alkaline pH (>9.0) levels. Here, we assessed how this species responds to ammonium under such conditions by isolating and analyzing the functions of a putative ammonium transporter (PutAMT1;1). PutAMT1;1 is the first member of the AMT1 (ammonium transporter) family that has been identified in P. tenuiflora. This gene (1) functionally complemented a yeast mutant deficient in ammonium uptake (2), is preferentially expressed in the anther of P. tenuiflora, and (3) is significantly upregulated by ammonium ions in both the shoot and roots. The PutAMT1;1 protein is localized in the plasma membrane and around the nuclear periphery in yeast cells and P. tenuiflora suspension cells. Immunoelectron microscopy analysis also indicated that PutAMT1;1 is localized in the endomembrane. The overexpression of PutAMT1;1 in A. thaliana enhanced plant growth, and increased plant susceptibility to toxic methylammonium (MeA). Here, we confirmed that PutAMT1;1 is an ammonium-inducible ammonium transporter in P. tenuiflora. On the basis of the results of PutAMT1;1 overexpression in A. thaliana, this gene might be useful for improving the root to shoot mobilization of MeA (or NH4(+)).
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Affiliation(s)
- Yuanyuan Bu
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
| | - Bo Sun
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
| | - Aimin Zhou
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
| | - Xinxin Zhang
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
| | - Imshik Lee
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
| | - Shenkui Liu
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China
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Mohd-Radzman NA, Djordjevic MA, Imin N. Nitrogen modulation of legume root architecture signaling pathways involves phytohormones and small regulatory molecules. FRONTIERS IN PLANT SCIENCE 2013; 4:385. [PMID: 24098303 PMCID: PMC3787543 DOI: 10.3389/fpls.2013.00385] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/11/2013] [Indexed: 05/20/2023]
Abstract
Nitrogen, particularly nitrate is an important yield determinant for crops. However, current agricultural practice with excessive fertilizer usage has detrimental effects on the environment. Therefore, legumes have been suggested as a sustainable alternative for replenishing soil nitrogen. Legumes can uniquely form nitrogen-fixing nodules through symbiotic interaction with specialized soil bacteria. Legumes possess a highly plastic root system which modulates its architecture according to the nitrogen availability in the soil. Understanding how legumes regulate root development in response to nitrogen availability is an important step to improving root architecture. The nitrogen-mediated root development pathway starts with sensing soil nitrogen level followed by subsequent signal transduction pathways involving phytohormones, microRNAs and regulatory peptides that collectively modulate the growth and shape of the root system. This review focuses on the current understanding of nitrogen-mediated legume root architecture including local and systemic regulations by different N-sources and the modulations by phytohormones and small regulatory molecules.
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Affiliation(s)
| | | | - Nijat Imin
- *Correspondence: Nijat Imin, Division of Plant Sciences, Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Linnaeus Building 134, Linnaeus Way, Canberra, ACT 0200, Australia e-mail:
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Scherzer S, Krol E, Kreuzer I, Kruse J, Karl F, von Rüden M, Escalante-Perez M, Müller T, Rennenberg H, Al-Rasheid KAS, Neher E, Hedrich R. The Dionaea muscipula ammonium channel DmAMT1 provides NH₄⁺ uptake associated with Venus flytrap's prey digestion. Curr Biol 2013; 23:1649-57. [PMID: 23954430 DOI: 10.1016/j.cub.2013.07.028] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/07/2013] [Accepted: 07/03/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND Ammonium transporter (AMT/MEP/Rh) superfamily members mediate ammonium uptake and retrieval. This pivotal transport system is conserved among all living organisms. For plants, nitrogen represents a macronutrient available in the soil as ammonium, nitrate, and organic nitrogen compounds. Plants living on extremely nutrient-poor soils have developed a number of adaptation mechanisms, including a carnivorous lifestyle. This study addresses the molecular nature, function, and regulation of prey-derived ammonium uptake in the Venus flytrap, Dionaea muscipula, one of the fastest active carnivores. RESULTS The Dionaea muscipula ammonium transporter DmAMT1 was localized in gland complexes where its expression was upregulated upon secretion. These clusters of cells decorating the inner trap surface are engaged in (1) secretion of an acidic digestive enzyme cocktail and (2) uptake of prey-derived nutrients. Voltage clamp of Xenopus oocytes expressing DmAMT1 and membrane potential recordings with DmAMT1-expressing Dionaea glands were used to monitor and compare electrophysiological properties of DmAMT1 in vitro and in planta. DmAMT1 exhibited the hallmark biophysical properties of a NH4(+)-selective channel. At depolarized membrane potentials (Vm = 0), the Km (3.2 ± 0.3 mM) indicated a low affinity of DmAMT1 for ammonium that increased systematically with negative going voltages. Upon hyperpolarization to, e.g., -200 mV, a Km of 0.14 ± 0.015 mM documents the voltage-dependent shift of DmAMT1 into a NH4(+) transport system of high affinity. CONCLUSIONS We suggest that regulation of glandular DmAMT1 and membrane potential readjustments of the endocrine cells provide for effective adaptation to varying, prey-derived ammonium sources.
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Affiliation(s)
- Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany; Department for Membrane Biophysics, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
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Koegel S, Ait Lahmidi N, Arnould C, Chatagnier O, Walder F, Ineichen K, Boller T, Wipf D, Wiemken A, Courty PE. The family of ammonium transporters (AMT) in Sorghum bicolor: two AMT members are induced locally, but not systemically in roots colonized by arbuscular mycorrhizal fungi. THE NEW PHYTOLOGIST 2013; 198:853-865. [PMID: 23461653 DOI: 10.1111/nph.12199] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/20/2013] [Indexed: 05/19/2023]
Abstract
Arbuscular mycorrhizal (AM) fungi contribute to plant nitrogen (N) acquisition. Recent studies demonstrated the transport of N in the form of ammonium during AM symbiosis. Here, we hypothesize that induction of specific ammonium transporter (AMT) genes in Sorghum bicolor during AM colonization might play a key role in the functionality of the symbiosis. For the first time, combining a split-root experiment and microdissection technology, we were able to assess the precise expression pattern of two AM-inducible AMTs, SbAMT3;1 and SbAMT4. Immunolocalization was used to localize the protein of SbAMT3;1. The expression of SbAMT3;1 and SbAMT4 was greatly induced locally in root cells containing arbuscules and in adjacent cells. However, a split-root experiment revealed that this induction was not systemic. By contrast, a strictly AM-induced phosphate transporter (SbPt11) was expressed systemically in the split-root experiment. However, a gradient of expression was apparent. Immunolocalization analyses demonstrated that SbAMT3;1 was present only in cells containing developing arbuscules. Our results show that the SbAMT3;1 and SbAMT4 genes are expressed in root cortical cells, which makes them ready to accommodate arbuscules, a process of considerable importance in view of the short life span of arbuscules. Additionally, SbAMT3;1 might play an important role in N transfer during AM symbiosis.
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Affiliation(s)
- Sally Koegel
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
| | - Nassima Ait Lahmidi
- UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France
| | - Christine Arnould
- UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France
| | - Odile Chatagnier
- UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France
| | - Florian Walder
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
| | - Kurt Ineichen
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
| | - Thomas Boller
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
| | - Daniel Wipf
- UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France
| | - Andres Wiemken
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
| | - Pierre-Emmanuel Courty
- Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland
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Criscuolo G, Valkov VT, Parlati A, Alves LM, Chiurazzi M. Molecular characterization of the Lotus japonicus NRT1(PTR) and NRT2 families. PLANT, CELL & ENVIRONMENT 2012; 35:1567-81. [PMID: 22458810 DOI: 10.1111/j.1365-3040.2012.02510.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrate is an essential element for plant growth, both as a primary nutrient in the nitrogen assimilation pathway and as an important signal for plant development. Low- and high-affinity transport systems are involved in the nitrate uptake from the soil and its distribution between different plant tissues. By an in silico search, we identified putative members of both systems in the model legume Lotus japonicus. We investigated, by a time course analysis, the transcripts abundance in root tissues of nine and four genes encoding putative low-affinity (NRT1) and high-affinity (NRT2) nitrate transporters, respectively. The genes were sub-classified as inducible, repressible and constitutive on the basis of their responses to provision of nitrate, auxin or cytokinin. Furthermore, the analysis of the pattern of expression in root and nodule tissues after Mesorhizobium loti inoculation permitted the identification of sequences significantly regulated during the symbiotic interaction. The interpretation of the global regulative networks obtained allowed to postulate roles for nitrate transporters as possible actors in the cross-talks between different signalling pathways triggered by biotic and abiotic factors.
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MESH Headings
- Anion Transport Proteins/genetics
- Anion Transport Proteins/metabolism
- Cytokinins/pharmacology
- Evolution, Molecular
- Gene Expression Regulation, Plant/drug effects
- Gene Regulatory Networks/genetics
- Genes, Plant/genetics
- Indoleacetic Acids/pharmacology
- Lotus/drug effects
- Lotus/genetics
- Lotus/microbiology
- Mesorhizobium/drug effects
- Mesorhizobium/physiology
- Multigene Family/genetics
- Nitrate Transporters
- Nitrates/pharmacology
- Phylogeny
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Promoter Regions, Genetic/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Root Nodules, Plant/cytology
- Root Nodules, Plant/drug effects
- Root Nodules, Plant/microbiology
- Time Factors
- Transcription, Genetic/drug effects
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Affiliation(s)
- Giuseppina Criscuolo
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 111, 80131, Napoli, Italy
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36
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Seabra AR, Pereira PA, Becker JD, Carvalho HG. Inhibition of glutamine synthetase by phosphinothricin leads to transcriptome reprograming in root nodules of Medicago truncatula. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:976-92. [PMID: 22414438 DOI: 10.1094/mpmi-12-11-0322] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Glutamine synthetase (GS) is a vital enzyme for the assimilation of ammonia into amino acids in higher plants. In legumes, GS plays a crucial role in the assimilation of the ammonium released by nitrogen-fixing bacteria in root nodules, constituting an important metabolic knob controlling the nitrogen (N) assimilatory pathways. To identify new regulators of nodule metabolism, we profiled the transcriptome of Medicago truncatula nodules impaired in N assimilation by specifically inhibiting GS activity using phosphinothricin (PPT). Global transcript expression of nodules collected before and after PPT addition (4, 8, and 24 h) was assessed using Affymetrix M. truncatula GeneChip arrays. Hundreds of genes were regulated at the three time points, illustrating the dramatic alterations in cell metabolism that are imposed on the nodules upon GS inhibition. The data indicate that GS inhibition triggers a fast plant defense response, induces premature nodule senescence, and promotes loss of root nodule identity. Consecutive metabolic changes were identified at the three time points analyzed. The results point to a fast repression of asparagine synthesis and of the glycolytic pathway and to the synthesis of glutamate via reactions alternative to the GS/GOGAT cycle. Several genes potentially involved in the molecular surveillance for internal organic N availability are identified and a number of transporters potentially important for nodule functioning are pinpointed. The data provided by this study contributes to the mapping of regulatory and metabolic networks involved in root nodule functioning and highlight candidate modulators for functional analysis.
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Affiliation(s)
- Ana R Seabra
- Instituto de Biologia Molecular e Celular da Universidade do Porto, Porto, Portugal
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37
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Pantoja O. High affinity ammonium transporters: molecular mechanism of action. FRONTIERS IN PLANT SCIENCE 2012; 3:34. [PMID: 22645581 PMCID: PMC3355798 DOI: 10.3389/fpls.2012.00034] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 02/06/2012] [Indexed: 05/26/2023]
Abstract
The importance of the family of high affinity ammonium transporters is demonstrated by the presence of these proteins in all domains of life, including bacteria, archaea, fungi, plants, and humans. The majority of the proteins that have been studied from this family show high affinity and selectivity for ammonium, are impermeable to alkaline cations, saturate rapidly at low millimolar concentrations and most of them, are also permeable to methylammonium. Crystallization of homologue proteins from bacteria and archaea has demonstrated that the functional entity corresponds to a trimer, with each monomer maintaining a conductive pore. Through molecular modeling, it has been demonstrated that even though the identity of the proteins between bacteria/archaea with those from plants is below 25%, the latter seem to maintain similar tertiary and quaternary structures, an observation that has helped to address the functionality of conserved residues by means of mutational analysis. Results have shown that changes in the extracellular binding site of some plant transporters may result in their inhibition or reduction in transport activity, while in Escherichia coli, dissimilar replacements like Phe/Ala or Ser/Leu that eliminate possible π-interactions or H-bonds with ammonium, respectively, lead to more active transporters. Active mutants with changes in the pair of conserved His in the center of the transporter suggest these residues are dispensable. Additional mutations have identified other important amino acids, both in the entrance of the pore and in cytoplasmic loops. Regulation of this family of transporters can be achieved by interactions of the C-terminal with cytoplasmic loops within the same monomer, or with a neighbor in the trimer. Depending on the interacting residues, these contacts may lead to the activation or inhibition of the protein. The aim of this review is to critically evaluate the newest findings on the role of the proposed amino acids that structure the ammonium pathway, as well as highlight the importance of additional residues that have been identified through mutational analyses.
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Affiliation(s)
- Omar Pantoja
- Instituto de Biotecnología, Universidad Nacional Autónoma de MéxicoCuernavaca, México
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Graff L, Obrdlik P, Yuan L, Loqué D, Frommer WB, von Wirén N. N-terminal cysteines affect oligomer stability of the allosterically regulated ammonium transporter LeAMT1;1. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:1361-73. [PMID: 21127027 DOI: 10.1093/jxb/erq379] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
AMMONIUM TRANSPORTER (AMT) proteins are conserved in all domains of life and mediate the transport of ammonium or ammonia across cell membranes. AMTs form trimers and use intermolecular interaction between subunits to regulate activity. So far, binding forces that stabilize AMT protein complexes are not well characterized. High temperature or reducing agents released mono- and dimeric forms from trimeric complexes formed by AMT1;1 from Arabidopsis and tomato. However, in the paralogue LeAMT1;3, trimeric complexes were not detected. LeAMT1;3 differs from the other AMTs by an unusually short N-terminus, suggesting a role for the N-terminus in oligomer stability. Truncation of the N-terminus in LeAMT1;1 destabilized the trimer and led to loss of functionality when expressed in yeast. Swapping of the N-terminus between LeAMT1;1 and LeAMT1;3 showed that sequences in the N-terminus of LeAMT1;1 are necessary and sufficient for stabilization of the interaction among the subunits. Two N-terminal cysteine residues are highly conserved among AMT1 transporters in plants but are lacking in LeAMT1;3. C3S or C27S variants of LeAMT1;1 showed reduced complex stability, which coincided with lower transport capacity for the substrate analogue methylammonium. Both cysteine-substituted LeAMT1;1 variants showed weaker interactions with the wildtype as determined by a quantitative analysis of the complex stability using the mating-based split-ubiquitin assay. These data indicate that the binding affinity of AMT1 subunits is stabilized by cysteines in the N-terminus and suggest a role for disulphide bridge formation via apoplastic N-terminal cysteine residues.
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Affiliation(s)
- Lucile Graff
- Institute for Plant Nutrition, University of Hohenheim, D-70593 Stuttgart, Germany
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Tsay YF, Ho CH, Chen HY, Lin SH. Integration of nitrogen and potassium signaling. ANNUAL REVIEW OF PLANT BIOLOGY 2011; 62:207-26. [PMID: 21495843 DOI: 10.1146/annurev-arplant-042110-103837] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Sensing and responding to soil nutrient fluctuations are vital for the survival of higher plants. Over the past few years, great progress has been made in our understanding of nitrogen and potassium signaling. Key components of the signaling pathways including sensors, kinases, miRNA, ubiquitin ligases, and transcriptional factors. These components mediate the transcriptional responses, root-architecture changes, and uptake-activity modulation induced by nitrate, ammonium, and potassium in the soil solution. Integration of these responses allows plants to compete for limited nutrients and to survive under nutrient deficiency or toxic nutrient excess. A future challenge is to extend the present fragmented sets of data to a comprehensive signaling network. Then, such knowledge and the accompanying molecular tools can be applied to improve the efficiency of nutrient utilization in crops.
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Affiliation(s)
- Yi-Fang Tsay
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
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40
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Song T, Gao Q, Xu Z, Song R. The cloning and characterization of two ammonium transporters in the salt-resistant green alga, Dunaliella viridis. Mol Biol Rep 2010; 38:4797-804. [PMID: 21153924 DOI: 10.1007/s11033-010-0621-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 11/26/2010] [Indexed: 11/26/2022]
Abstract
Ammonium (NH(4) (+)) transport is a key process in nitrogen metabolism. To elucidate the role of ammonium transporters in the nitrogen consumption of the salt-resistant green alga, Dunaliella viridis, two ammonium transporter genes, DvAMT1;1 and DvAMT1;2, were isolated from cDNA libraries of D. viridis. DvAMT1;1 and DvAMT1;2 share only 40% amino acid identity, indicating that they have highly divergent coding sequences. Functional complementation in a yeast mutant defective in ammonium uptake indicated that both DvAMT1;1 and DvAMT1;2 were functional ammonium transporters. Quantitative RT-PCR showed similar expression patterns, but different transcript abundance levels, for DvAMT1;1 and DvAMT1;2 under different nitrogen conditions. Both were induced at low nitrogen and inhibited at high nitrogen concentrations, especially when NH(4) (+) was the nitrogen source. At the transcriptional level, DvAMT1;1 was diurnally regulated, while DvAMT1;2 was not. In addition, under NaCl concentrations that ranged from 0.5 to 3 M, DvAMT1;1 was down-regulated at the higher salt conditions; conversely, DvAMT1;2 maintained a relatively low, but stable, transcript abundance. The observed differences in transcriptional regulation of DvAMT1;1 and DvAMT1;2 are indicative of their diverse physiological functions in D. viridis.
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Affiliation(s)
- Ting Song
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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41
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Rogato A, D’Apuzzo E, Barbulova A, Omrane S, Parlati A, Carfagna S, Costa A, Schiavo FL, Esposito S, Chiurazzi M. Characterization of a developmental root response caused by external ammonium supply in Lotus japonicus. PLANT PHYSIOLOGY 2010; 154:784-95. [PMID: 20688979 PMCID: PMC2948985 DOI: 10.1104/pp.110.160309] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 08/03/2010] [Indexed: 05/04/2023]
Abstract
Plants respond to changes of nutrient availability in the soil by modulating their root system developmental plan. This response is mediated by systemic changes of the nutritional status and/or by local perception of specific signals. The effect of nitrate on Arabidopsis (Arabidopsis thaliana) root development represents a paradigm of these responses, and nitrate transporters are involved both in local and systemic control. Ammonium (NH(4)(+)) represents an important nitrogen (N) source for plants, although toxicity symptoms are often associated with high NH(4)(+) concentration when this is present as the only N source. The reason for these effects is still controversial, and mechanisms associating ammonium supply and plant developmental programs are completely unknown. We determined in Lotus japonicus the range of ammonium concentration that significantly inhibits the elongation of primary and lateral roots without affecting the biomass of the shoot. The comparison of the growth phenotypes in different N conditions indicated the specificity of the ammonium effect, suggesting that this was not mediated by assimilatory negative feedback mechanisms. In the range of inhibitory NH(4)(+) conditions, only the LjAMT1;3 gene, among the members of the LjAMT1 family, showed a strong increased transcription that was reflected by an enlarged topology of expression. Remarkably, the short-root phenotype was phenocopied in transgenic lines by LjAMT1;3 overexpression independently of ammonium supply, and the same phenotype was not induced by another AMT1 member. These data describe a new plant mechanism to cope with environmental changes, giving preliminary information on putative actors involved in this specific ammonium-induced response.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Maurizio Chiurazzi
- Institute of Genetics and Biophysics, A. Buzzati Traverso, 80131 Naples, Italy (A.R., E.D., A.B., S.O., A.P., M.C.); Dipartimento delle Scienze Biologiche, Università degli Studi di Napoli Federico II, 80139 Naples, Italy (S.C.); Università degli Studi di Padova, I–35131 Padova, Italy (A.C., F.L.S.); Dipartimento di Biologia Strutturale e Funzionale, Università degli Studi di Napoli Federico II, 80129 Naples, Italy (S.E.)
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42
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Benedito VA, Li H, Dai X, Wandrey M, He J, Kaundal R, Torres-Jerez I, Gomez SK, Harrison MJ, Tang Y, Zhao PX, Udvardi MK. Genomic inventory and transcriptional analysis of Medicago truncatula transporters. PLANT PHYSIOLOGY 2010; 152:1716-30. [PMID: 20023147 PMCID: PMC2832251 DOI: 10.1104/pp.109.148684] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 12/15/2009] [Indexed: 05/20/2023]
Abstract
Transporters move hydrophilic substrates across hydrophobic biological membranes and play key roles in plant nutrition, metabolism, and signaling and, consequently, in plant growth, development, and responses to the environment. To initiate and support systematic characterization of transporters in the model legume Medicago truncatula, we identified 3,830 transporters and classified 2,673 of these into 113 families and 146 subfamilies. Analysis of gene expression data for 2,611 of these transporters identified 129 that are expressed in an organ-specific manner, including 50 that are nodule specific and 36 specific to mycorrhizal roots. Further analysis uncovered 196 transporters that are induced at least 5-fold during nodule development and 44 in roots during arbuscular mycorrhizal symbiosis. Among the nodule- and mycorrhiza-induced transporter genes are many candidates for known transport activities in these beneficial symbioses. The data presented here are a unique resource for the selection and functional characterization of legume transporters.
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43
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Guether M, Neuhäuser B, Balestrini R, Dynowski M, Ludewig U, Bonfante P. A mycorrhizal-specific ammonium transporter from Lotus japonicus acquires nitrogen released by arbuscular mycorrhizal fungi. PLANT PHYSIOLOGY 2009; 150:73-83. [PMID: 19329566 PMCID: PMC2675747 DOI: 10.1104/pp.109.136390] [Citation(s) in RCA: 177] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2009] [Accepted: 03/24/2009] [Indexed: 05/19/2023]
Abstract
In mycorrhizal associations, the fungal partner assists its plant host by providing nitrogen (N) in addition to phosphate. Arbuscular mycorrhizal (AM) fungi have access to inorganic or organic forms of N and translocate them via arginine from the extra- to the intraradical mycelium, where the N is transferred to the plant without any carbon skeleton. However, the molecular form in which N is transferred, as well as the involved mechanisms, is still under debate. NH(4)(+) seems to be the preferential transferred molecule, but no plant ammonium transporter (AMT) has been identified so far. Here, we offer evidence of a plant AMT that is involved in N uptake during mycorrhiza symbiosis. The gene LjAMT2;2, which has been shown to be the highest up-regulated gene in a transcriptomic analysis of Lotus japonicus roots upon colonization with Gigaspora margarita, has been characterized as a high-affinity AMT belonging to the AMT2 subfamily. It is exclusively expressed in the mycorrhizal roots, but not in the nodules, and transcripts have preferentially been located in the arbusculated cells. Yeast (Saccharomyces cerevisiae) mutant complementation has confirmed its functionality and revealed its dependency on acidic pH. The transport experiments using Xenopus laevis oocytes indicated that, unlike other plant AMTs, LjAMT2;2 transports NH(3) instead of NH(4)(+). Our results suggest that the transporter binds charged ammonium in the apoplastic interfacial compartment and releases the uncharged NH(3) into the plant cytoplasm. The implications of such a finding are discussed in the context of AM functioning and plant phosphorus uptake.
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Affiliation(s)
- Mike Guether
- Department of Plant Biology, University of Torino and Istituto per la Protezione delle Piante/Consiglio Nazionale delle Ricerche, 10125 Torino, Italy
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44
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Omrane S, Ferrarini A, D'Apuzzo E, Rogato A, Delledonne M, Chiurazzi M. Symbiotic competence in Lotus japonicus is affected by plant nitrogen status: transcriptomic identification of genes affected by a new signalling pathway. THE NEW PHYTOLOGIST 2009; 183:380-394. [PMID: 19500268 DOI: 10.1111/j.1469-8137.2009.02873.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
In leguminous plants, symbiotic nitrogen (N) fixation performances and N environmental conditions are linked because nodule initiation, development and functioning are greatly influenced by the amount of available N sources. We demonstrate here that N supply also controls, beforehand, the competence of leguminous plants to perform the nodulation program. Lotus japonicus plants preincubated for 10 d in high-N conditions, and then transferred to low N before the Mesorhizobium loti inoculation, had reduced nodulation. This phenotype was maintained for at least 6 d and a complete reacquisition of the symbiotic competence was observed only after 9 d. The time-course analysis of the change of the symbiotic phenotype was analysed by transcriptomics. The differentially expressed genes identified are mostly involved in metabolic pathways. However, the transcriptional response also includes genes belonging to other functional categories such as signalling, stress response and transcriptional regulation. Some of these genes show a molecular identity and a regulation profile, that suggest a role as possible molecular links between the N-dependent plant response and the nodule organogenesis program.
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Affiliation(s)
- Selim Omrane
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 131, Napoli, Italy
| | - Alberto Ferrarini
- Università degli Studi di Verona, Strada Le Grazie 15 Cà Vignal, I-37134, Verona, Italy
| | - Enrica D'Apuzzo
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 131, Napoli, Italy
| | - Alessandra Rogato
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 131, Napoli, Italy
| | - Massimo Delledonne
- Università degli Studi di Verona, Strada Le Grazie 15 Cà Vignal, I-37134, Verona, Italy
| | - Maurizio Chiurazzi
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 131, Napoli, Italy
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45
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Rogato A, D'Apuzzo E, Barbulova A, Omrane S, Stedel C, Simon-Rosin U, Katinakis P, Flemetakis M, Udvardi M, Chiurazzi M. Tissue-specific down-regulation of LjAMT1;1 compromises nodule function and enhances nodulation in Lotus japonicus. PLANT MOLECULAR BIOLOGY 2008; 68:585-595. [PMID: 18781388 DOI: 10.1007/s11103-008-9394-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Accepted: 08/27/2008] [Indexed: 05/26/2023]
Abstract
Plant ammonium transporters of the AMT1 family are involved in N-uptake from the soil and ammonium transport, and recycling within the plant. Although AMT1 genes are known to be expressed in nitrogen-fixing nodules of legumes, their precise roles in this specialized organ remain unknown. We have taken a reverse-genetic approach to decipher the physiological role of LjAMT1;1 in Lotus japonicus nodules. LjAMT1;1 is normally expressed in both the infected zone and the vascular tissue of Lotus nodules. Inhibition of LjAMT1;1 gene expression, using an antisense gene construct driven by a leghemoglobin promoter resulted in a substantial reduction of LjAMT1;1 transcript in the infected tissue but not the vascular bundles of transgenic plants. As a result, the nitrogen-fixing activity of nodules was partially impaired and nodule number increased compared to control plants. Expression of LjAMT1;1-GFP fusion protein in plant cells indicated a plasma-membrane location for the LjAMT1;1 protein. Taken together, the results are consistent with a role of LjAMT1;1 in retaining ammonium derived from symbiotic nitrogen fixation in plant cells prior to its assimilation.
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Affiliation(s)
- Alessandra Rogato
- Institute of Genetics and Biophysics A. Buzzati Traverso, Via P. Castellino 12, 80131, Napoli, Italy
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46
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Couturier J, Montanini B, Martin F, Brun A, Blaudez D, Chalot M. The expanded family of ammonium transporters in the perennial poplar plant. THE NEW PHYTOLOGIST 2007; 174:137-150. [PMID: 17335504 DOI: 10.1111/j.1469-8137.2007.01992.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
* Ammonium and nitrate are the prevalent nitrogen sources for growth and development of higher plants. Here, we report on the characterization of the ammonium transporter (AMT) family in the perennial species Populus trichocarpa. * In silico analysis and expression analysis of AMT genes from poplar was performed. In addition, AMT1;2 and AMT1;6 function was studied in detail by heterologous expression in yeast. * The P. trichocarpa genome contains 14 putative AMTs, which is more than twice the number of AMTs in Arabidopsis. In roots, the high-affinity AMT1;2 strongly increased upon mycorrhiza formation and might be partly responsible for the high-affinity ammonium uptake component measured in poplar. Transcript level for the high-affinity AMT1;6 was strongly affected by the diurnal cycle. AMT3;1 was exclusively expressed in senescing poplar leaves. Remarkably AMT2;1 was highly expressed in leaves while AMT2;2 was mostly expressed in petioles. Specific expression of AMT1;5 in stamen and of AMT1;6 in female flower indicate that they have key functions in reproductive organ development in poplar. * The present study provides basic genomic and transcriptomic information for the poplar AMT family and will pave the way for deciphering the precise role of AMTs in poplar physiology.
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Affiliation(s)
- Jérémy Couturier
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - Barbara Montanini
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - Francis Martin
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - Annick Brun
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - Damien Blaudez
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - Michel Chalot
- Research Unit INRA/UHP 1136 'Tree-microbe Interactions', Nancy-University, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
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47
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Loqué D, Yuan L, Kojima S, Gojon A, Wirth J, Gazzarrini S, Ishiyama K, Takahashi H, von Wirén N. Additive contribution of AMT1;1 and AMT1;3 to high-affinity ammonium uptake across the plasma membrane of nitrogen-deficient Arabidopsis roots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 48:522-34. [PMID: 17026539 DOI: 10.1111/j.1365-313x.2006.02887.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In Arabidopsis four root-expressed AMT genes encode functional ammonium transporters, which raises the question of their role in primary ammonium uptake. After pre-culturing under nitrogen-deficiency conditions, we quantified the influx of (15)N-labeled ammonium in T-DNA insertion lines and observed that the loss of either AMT1;1 or AMT1;3 led to a decrease in the high-affinity ammonium influx of approximately 30%. Under nitrogen-sufficient conditions the ammonium influx was lower in Columbia glabra compared with Wassilewskija (WS), and AMT1;1 did not contribute significantly to the ammonium influx in Col-gl. Ectopic expression of AMT1;3 under the control of a 35S promoter in either of the insertion lines amt1;3-1 or amt1;1-1 increased the ammonium influx above the level of their corresponding wild types. In transgenic lines carrying AMT-promoter-GFP constructs, the promoter activities of AMT1;1 and AMT1;3 were both upregulated under nitrogen-deficiency conditions and were localized to the rhizodermis, including root hairs. AMT gene-GFP fusions that were stably expressed under the control of their own promoters were localized to the plasma membrane. The double insertion line amt1;1-1amt1;3-1 showed a decreased sensitivity to the toxic ammonium analog methylammonium and a decrease in the ammonium influx of up to 70% relative to wild-type plants. These results suggest an additive contribution of AMT1;1 and AMT1;3 to the overall ammonium uptake capacity in Arabidopsis roots under nitrogen-deficiency conditions.
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Affiliation(s)
- Dominique Loqué
- Molekulare Pflanzenernährung, Universität Hohenheim, D-70593 Stuttgart, Germany
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48
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Benedito VA, Dai X, He J, Zhao PX, Udvardi MK. Functional genomics of plant transporters in legume nodules. FUNCTIONAL PLANT BIOLOGY : FPB 2006; 33:731-736. [PMID: 32689283 DOI: 10.1071/fp06085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Accepted: 05/25/2006] [Indexed: 06/11/2023]
Abstract
Over the past few decades, a combination of physiology, biochemistry, molecular and cell biology, and genetics has given us a basic understanding of some of the key transport processes at work in nitrogen-fixing legume nodules, especially those involved in nutrient exchange between infected plant cells and their endosymbiotic rhizobia. However, our knowledge in this area remains patchy and dispersed over numerous legume species. Recent progress in the areas of genomics and functional genomics of the two model legumes, Medicago truncatula and Lotus japonicus is rapidly filling the gap in knowledge about which plant transporter genes are expressed constitutively in nodules and other organs, and which are induced or expressed specifically in nodules. The latter class in particular is the focus of current efforts to understand specialised, nodule-specific roles of transporters. This article briefly reviews past work on the biochemistry and molecular biology of plant transporters in nodules, before describing recent work in the areas of transcriptomics and bioinformatics. Finally, we consider where functional genomics together with more classical approaches are likely to lead us in this area of research in the future.
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Affiliation(s)
- Vagner A Benedito
- Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Xinbin Dai
- Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Ji He
- Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Patrick X Zhao
- Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Michael K Udvardi
- Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
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Li XD, Lupo D, Zheng L, Winkler F. Structural and functional insights into the AmtB/Mep/Rh protein family. Transfus Clin Biol 2006; 13:65-9. [PMID: 16564194 DOI: 10.1016/j.tracli.2006.02.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
X-ray crystallography revealed a similar architecture of the ammonium transport protein AmtB from Escherichia coli and the homologous protein Amt-1 from Archaeoglobus fulgidus. Furthermore, the atomic structures suggest that the proteins conduct ammonia (NH3) rather than ammonium ions (NH4+). These findings indicate that the more than 350 members of the ammonium transporter/methylamine permease/Rhesus (Amt/Mep/Rh) protein family found in archaea, bacteria, fungi, plants and animals are ammonia-conducting channels rather than ammonium ion transporters. The essential part of these proteins is the narrow hydrophobic ammonia-conducting pore with two highly conserved histidine residues located in the middle of the pore. A specific ammonium ion binding site is found at the extracellular entry site of E. coli AmtB. E. coli AmtB and its regulator GlnK form an effective ammonium sensory system that couples intracellular gene regulation by the nitrogen control system to external changes in ammonium availability. Based on structural and functional analysis of various mutants, two conserved histidine residues were found to be essential for substrate conductance also in the functional eukaryotic ammonium transporters. The next big challenge in the field surely is to determine the atomic structure of Rh proteins.
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Affiliation(s)
- X-D Li
- Biomolecular Research, Paul Scherrer Institute, OFLC 104, CH-5232 Villigen, Switzerland.
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50
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Abstract
The structure determination of the ammonium transport protein AmtB from Escherichia coli strongly indicates that the members of the ubiquitous ammonium transporter/methylamine permease/Rhesus (Amt/MEP/Rh) protein family are ammonia-conducting channels rather than ammonium ion transporters. The most conserved part of these proteins, apart from the common overall structure with 11 transmembrane helices, is the pore lined by hydrophobic side chains except for two highly conserved histidine residues. A high-affinity ion-binding site specific for ammonium is present at the extracellular pore entry of the Amt/MEP proteins. It is proposed to play an important role in enhancing net transport at very low external ammonium concentrations and to provide discrimination against water. The site is not conserved in the animal Rhesus proteins which are implicated in ammonium homeostasis and saturate at millimolar ammonium concentrations. Many aspects of the biological function of these ammonia channels are still poorly understood and further studies in cellular systems are needed. Likewise, studies with purified, reconstituted Amt/MEP/Rh proteins will be needed to resolve open mechanistic questions and gain a more quantitative understanding of the conduction mechanism in general and for different subfamily representatives.
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Affiliation(s)
- Fritz K Winkler
- Structural Biology, Biomolecular Research, Paul Scherrer Institut, 5232 Villigen, Switzerland.
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