1
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Shen C, Li Q, An Y, Zhou Y, Zhang Y, He F, Chen L, Liu C, Mao W, Wang X, Liang H, Yin W, Xia X. The transcription factor GNC optimizes nitrogen use efficiency and growth by up-regulating the expression of nitrate uptake and assimilation genes in poplar. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4778-4792. [PMID: 35526197 DOI: 10.1093/jxb/erac190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 05/05/2022] [Indexed: 06/14/2023]
Abstract
Plants have evolved complex mechanisms to cope with the fluctuating environmental availability of nitrogen. However, potential genes modulating plant responses to nitrate are yet to be characterized. Here, a poplar GATA transcription factor gene PdGNC (GATA nitrate-inducible carbon-metabolism-involved) was found to be strongly induced by low nitrate. Overexpressing PdGNC in poplar clone 717-1B4 (P. tremula × alba) significantly improved nitrate uptake, remobilization, and assimilation with higher nitrogen use efficiency (NUE) and faster growth, particularly under low nitrate conditions. Conversely, CRISPR/Cas9-mediated poplar mutant gnc exhibited decreased nitrate uptake, relocation, and assimilation, combined with lower NUE and slower growth. Assays with yeast one-hybrid, electrophoretic mobility shift, and a dual-luciferase reporter showed that PdGNC directly activated the promoters of nitrogen pathway genes PdNRT2.4b, PdNR, PdNiR, and PdGS2, leading to a significant increase in nitrate utilization in poplar. As expected, the enhanced NUE promoted growth under low nitrate availability. Taken together, our data show that PdGNC plays an important role in the regulation of NUE and growth in poplar by improving nitrate acquisition, remobilization, and assimilation, and provide a promising strategy for molecular breeding to improve productivity under nitrogen limitation in trees.
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Affiliation(s)
- Chao Shen
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Qing Li
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Yi An
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Yangyan Zhou
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Yue Zhang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Fang He
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Lingyun Chen
- Hangzhou Lifeng Seed Co., Ltd, Hangzhou, Zhejiang 310000, China
| | - Chao Liu
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Wei Mao
- Salver Academy of Botany, Rizhao, Shandong 276800, China
| | - Xiaofei Wang
- Salver Academy of Botany, Rizhao, Shandong 276800, China
| | - Haiying Liang
- Department of Genetics and Biochemistry, Clemson University, Clemson, South Carolina, USA
| | - Weilun Yin
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
| | - Xinli Xia
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Beijing Forestry University, Beijing, China
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Li K, Zhang S, Tang S, Zhang J, Dong H, Yang S, Qu H, Xuan W, Gu M, Xu G. The rice transcription factor Nhd1 regulates root growth and nitrogen uptake by activating nitrogen transporters. PLANT PHYSIOLOGY 2022; 189:1608-1624. [PMID: 35512346 PMCID: PMC9237666 DOI: 10.1093/plphys/kiac178] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Plants adjust root architecture and nitrogen (N) transporter activity to meet the variable N demand, but their integrated regulatory mechanism remains unclear. We have previously reported that a floral factor in rice (Oryza sativa), N-mediated heading date-1 (Nhd1), regulates flowering time. Here, we show that Nhd1 can directly activate the transcription of the high-affinity ammonium (NH4+) transporter 1;3 (OsAMT1;3) and the dual affinity nitrate (NO3-) transporter 2.4 (OsNRT2.4). Knockout of Nhd1 inhibited root growth in the presence of NO3- or a low concentration of NH4+. Compared to the wild-type (WT), nhd1 and osamt1;3 mutants showed a similar decrease in root growth and N uptake under low NH4+ supply, while nhd1 and osnrt2.4 mutants showed comparable root inhibition and altered NO3- translocation in shoots. The defects of nhd1 mutants in NH4+ uptake and root growth response to various N supplies were restored by overexpression of OsAMT1;3 or OsNRT2.4. However, when grown in a paddy field with low N availability, nhd1 mutants accumulated more N and achieved a higher N uptake efficiency (NUpE) due to the delayed flowering time and prolonged growth period. Our findings reveal a molecular mechanism underlying the growth duration-dependent NUpE.
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Affiliation(s)
- Kangning Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | | | - Shuo Tang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Jun Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Hongzhang Dong
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shihan Yang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Hongye Qu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Wei Xuan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Mian Gu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Guohua Xu
- Authors for correspondence: (S.Z.); (G.X.)
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Drew D, North RA, Nagarathinam K, Tanabe M. Structures and General Transport Mechanisms by the Major Facilitator Superfamily (MFS). Chem Rev 2021; 121:5289-5335. [PMID: 33886296 PMCID: PMC8154325 DOI: 10.1021/acs.chemrev.0c00983] [Citation(s) in RCA: 168] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Indexed: 12/12/2022]
Abstract
The major facilitator superfamily (MFS) is the largest known superfamily of secondary active transporters. MFS transporters are responsible for transporting a broad spectrum of substrates, either down their concentration gradient or uphill using the energy stored in the electrochemical gradients. Over the last 10 years, more than a hundred different MFS transporter structures covering close to 40 members have provided an atomic framework for piecing together the molecular basis of their transport cycles. Here, we summarize the remarkable promiscuity of MFS members in terms of substrate recognition and proton coupling as well as the intricate gating mechanisms undergone in achieving substrate translocation. We outline studies that show how residues far from the substrate binding site can be just as important for fine-tuning substrate recognition and specificity as those residues directly coordinating the substrate, and how a number of MFS transporters have evolved to form unique complexes with chaperone and signaling functions. Through a deeper mechanistic description of glucose (GLUT) transporters and multidrug resistance (MDR) antiporters, we outline novel refinements to the rocker-switch alternating-access model, such as a latch mechanism for proton-coupled monosaccharide transport. We emphasize that a full understanding of transport requires an elucidation of MFS transporter dynamics, energy landscapes, and the determination of how rate transitions are modulated by lipids.
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Affiliation(s)
- David Drew
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Rachel A. North
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Kumar Nagarathinam
- Center
of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Lübeck, D-23538, Lübeck, Germany
| | - Mikio Tanabe
- Structural
Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan
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4
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Cui L, Zhang C, Li Z, Xian T, Wang L, Zhang Z, Zhu G, Peng X. Two plastidic glycolate/glycerate translocator 1 isoforms function together to transport photorespiratory glycolate and glycerate in rice chloroplasts. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:2584-2599. [PMID: 33483723 DOI: 10.1093/jxb/erab020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
The photorespiratory pathway is highly compartmentalized. As such, metabolite shuttles between organelles are critical to ensure efficient photorespiratory carbon flux. Arabidopsis plastidic glycolate/glycerate translocator 1 (PLGG1) has been reported as a key chloroplastic glycolate/glycerate transporter. Two homologous genes, OsPLGG1a and OsPLGG1b, have been identified in the rice genome, although their distinct functions and relationships remain unknown. Herein, our analysis of exogenous expression in oocytes and yeast shows that both OsPLGG1a and OsPLGG1b have the ability to transport glycolate and glycerate. Furthermore, we demonstrate in planta that the perturbation of OsPLGG1a or OsPLGG1b expression leads to extensive accumulation of photorespiratory metabolites, especially glycolate and glycerate. Under ambient CO2 conditions, loss-of-function osplgg1a or osplgg1b mutant plants exhibited significant decreases in photosynthesis efficiency, starch accumulation, plant height, and crop productivity. These morphological defects were almost entirely recovered when the mutant plants were grown under elevated CO2 conditions. In contrast to osplgg1a, osplgg1b mutant alleles produced a mild photorespiratory phenotype and had reduced accumulation of photorespiratory metabolites. Subcellular localization analysis showed that OsPLGG1a and OsPLGG1b are located in the inner and outer membranes of the chloroplast envelope, respectively. In vitro and in vivo experiments revealed that OsPLGG1a and OsPLGG1b have a direct interaction. Our results indicate that both OsPLGG1a and OsPLGG1b are chloroplastic glycolate/glycerate transporters required for photorespiratory metabolism and plant growth, and that they may function as a singular complex.
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Affiliation(s)
- Lili Cui
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Chuanling Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Zhichao Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Tuxiu Xian
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Limin Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Zhisheng Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Guohui Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Xinxiang Peng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
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5
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Wu B, Chen Z, Xu X, Chen R, Wang S, Xu H, Lin F. Harnessing a Transient Gene Expression System in Nicotiana benthamiana to Explore Plant Agrochemical Transporters. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10030524. [PMID: 33799776 PMCID: PMC7998108 DOI: 10.3390/plants10030524] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 05/20/2023]
Abstract
Functional characterization of plant agrichemical transporters provided an opportunity to discover molecules that have a high mobility in plants and have the potential to increase the amount of pesticides reaching damage sites. Agrobacterium-mediated transient expression in tobacco is simple and fast, and its protein expression efficiency is high; this system is generally used to mediate heterologous gene expression. In this article, transient expression of tobacco nicotine uptake permease (NtNUP1) and rice polyamine uptake transporter 1 (OsPUT1) in Nicotiana benthamiana was performed to investigate whether this system is useful as a platform for studying the interactions between plant transporters and pesticides. The results showed that NtNUP1 increases nicotine uptake in N. benthamiana foliar discs and protoplasts, indicating that this transient gene expression system is feasible for studying gene function. Moreover, yeast expression of OsPUT1 apparently increases methomyl uptake. Overall, this method of constructing a transient gene expression system is useful for improving the efficiency of analyzing the functions of plant heterologous transporter-encoding genes and revealed that this system can be further used to study the functions of transporters and pesticides, especially their interactions.
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Affiliation(s)
- Bingqi Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
| | - Zhiting Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
- Institute of Quality Standard and Monitoring Technology for Agro-Products of Guangdong Academy of Agricultural Sciences, Guangzhou 510642, China
| | - Xiaohui Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
| | - Ronghua Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
| | - Siwei Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
| | - Hanhong Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
- Correspondence: (H.X.); (F.L.); Tel.: +86-20-8528-5127 (H.X. & F.L.)
| | - Fei Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (B.W.); (Z.C.); (X.X.); (R.C.); (S.W.)
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (H.X.); (F.L.); Tel.: +86-20-8528-5127 (H.X. & F.L.)
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Luo B, Xu M, Zhao L, Xie P, Chen Y, Harwood W, Xu G, Fan X, Miller AJ. Overexpression of the High-Affinity Nitrate Transporter OsNRT2.3b Driven by Different Promoters in Barley Improves Yield and Nutrient Uptake Balance. Int J Mol Sci 2020; 21:E1320. [PMID: 32075298 PMCID: PMC7072886 DOI: 10.3390/ijms21041320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/07/2020] [Accepted: 02/13/2020] [Indexed: 11/29/2022] Open
Abstract
Improving nitrogen use efficiency (NUE) is very important for crops throughout the world. Rice mainly utilizes ammonium as an N source, but it also has four NRT2 genes involved in nitrate transport. The OsNRT2.3b transporter is important for maintaining cellular pH under mixed N supplies. Overexpression of this transporter driven by a ubiquitin promoter in rice greatly improved yield and NUE. This strategy for improving the NUE of crops may also be important for other cereals such as wheat and barley, which also face the challenges of nutrient uptake balance. To test this idea, we constructed transgenic barley lines overexpressing OsNRT2.3b. These transgenic barley lines overexpressing the rice transporter exhibited improved growth, yield, and NUE. We demonstrated that NRT2 family members and the partner protein HvNAR2.3 were also up-regulated by nitrate treatment (0.2 mM) in the transgenic lines. This suggests that the expression of OsNRT2.3b and other HvNRT2 family members were all up-regulated in the transgenic barley to increase the efficiency of N uptake and usage. We also compared the ubiquitin (Ubi) and a phloem-specific (RSs1) promoter-driven expression of OsNRT2.3b. The Ubi promoter failed to improve nutrient uptake balance, whereas the RSs1 promoter succeed in increasing the N, P, and Fe uptake balance. The nutrient uptake enhancement did not include Mn and Mg. Surprisingly, we found that the choice of promoter influenced the barley phenotype, not only increasing NUE and grain yield, but also improving nutrient uptake balance.
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Affiliation(s)
- Bingbing Luo
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Man Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Limei Zhao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Peng Xie
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Yi Chen
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK; (Y.C.); (W.H.)
| | - Wendy Harwood
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK; (Y.C.); (W.H.)
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; (B.L.); (M.X.); (L.Z.); (P.X.); (G.X.)
| | - Anthony J. Miller
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK; (Y.C.); (W.H.)
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Pike S, Matthes MS, McSteen P, Gassmann W. Using Xenopus laevis Oocytes to Functionally Characterize Plant Transporters. ACTA ACUST UNITED AC 2019; 4:e20087. [PMID: 30707001 DOI: 10.1002/cppb.20087] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Functionally characterizing plant membrane transport proteins is challenging. Typically, heterologous systems are used to study them. Immature eggs (oocytes) of the South African clawed frog Xenopus laevis are considered an ideal expression system for such studies. These large oocytes have a low number of endogenous transport systems in their plasma membranes and highly express foreign mRNA; the oocyte plasma membrane is the default destination of integral membrane proteins that lack recognized organellar sorting signals. These features facilitate almost background-free characterization of putative plant membrane transporters. Here we describe how to isolate Xenopus laevis oocytes, prepare capped sense RNA (cRNA) of the maize boron importer TASSEL-LESS1 (TLS1) as an example, microinject the cRNA into the isolated oocytes, and functionally assess the boron import capabilities of TLS1 in an oocyte swelling assay. These protocols can be easily adapted to study other plant and non-plant transporters with putative import function. © 2019 by John Wiley & Sons, Inc.
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Affiliation(s)
- Sharon Pike
- Division of Plant Sciences, Bond Life Sciences Center, and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri
| | - Michaela S Matthes
- Division of Biological Sciences, Bond Life Sciences Center, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, Missouri
| | - Paula McSteen
- Division of Biological Sciences, Bond Life Sciences Center, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, Missouri
| | - Walter Gassmann
- Division of Plant Sciences, Bond Life Sciences Center, and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri
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8
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Kryvoruchko IS, Routray P, Sinharoy S, Torres-Jerez I, Tejada-Jiménez M, Finney LA, Nakashima J, Pislariu CI, Benedito VA, González-Guerrero M, Roberts DM, Udvardi MK. An Iron-Activated Citrate Transporter, MtMATE67, Is Required for Symbiotic Nitrogen Fixation. PLANT PHYSIOLOGY 2018; 176:2315-2329. [PMID: 29284744 PMCID: PMC5841734 DOI: 10.1104/pp.17.01538] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 12/21/2017] [Indexed: 05/23/2023]
Abstract
Iron (Fe) is an essential micronutrient for symbiotic nitrogen fixation in legume nodules, where it is required for the activity of bacterial nitrogenase, plant leghemoglobin, respiratory oxidases, and other Fe proteins in both organisms. Fe solubility and transport within and between plant tissues is facilitated by organic chelators, such as nicotianamine and citrate. We have characterized a nodule-specific citrate transporter of the multidrug and toxic compound extrusion family, MtMATE67 of Medicago truncatula The MtMATE67 gene was induced early during nodule development and expressed primarily in the invasion zone of mature nodules. The MtMATE67 protein was localized to the plasma membrane of nodule cells and also the symbiosome membrane surrounding bacteroids in infected cells. In oocytes, MtMATE67 transported citrate out of cells in an Fe-activated manner. Loss of MtMATE67 gene function resulted in accumulation of Fe in the apoplasm of nodule cells and a substantial decrease in symbiotic nitrogen fixation and plant growth. Taken together, the results point to a primary role of MtMATE67 in citrate efflux from nodule cells in response to an Fe signal. This efflux is necessary to ensure Fe(III) solubility and mobility in the apoplasm and uptake into nodule cells. Likewise, MtMATE67-mediated citrate transport into the symbiosome space would increase the solubility and availability of Fe(III) for rhizobial bacteroids.
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Affiliation(s)
| | - Pratyush Routray
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996
| | | | | | - Manuel Tejada-Jiménez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA), Universidad Politécnica de Madrid, Madrid 28223, Spain
| | | | | | | | - Vagner A Benedito
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, West Virginia 26506
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA), Universidad Politécnica de Madrid, Madrid 28223, Spain
| | - Daniel M Roberts
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996
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Wei J, Zheng Y, Feng H, Qu H, Fan X, Yamaji N, Ma JF, Xu G. OsNRT2.4 encodes a dual-affinity nitrate transporter and functions in nitrate-regulated root growth and nitrate distribution in rice. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1095-1107. [PMID: 29385597 DOI: 10.1093/jxb/erx486] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/19/2017] [Indexed: 05/14/2023]
Abstract
Plant NRT2 nitrate transporters commonly require a partner protein, NAR2, for transporting nitrate at low concentrations, but their role in plants is not well understood. In this study, we characterized the gene for one of these transporters in the rice genome, OsNRT2.4, in terms of its activity and roles in rice grown in environments with different N supply. In Xenopus oocytes, OsNRT2.4 alone without OsNAR2 co-expression facilitated nitrate uptake showing biphasic kinetics at a wide concentration range, with high- and low-affinity KM values of 0.15 and 4 mM, respectively. OsNRT2.4 did not have nitrate efflux or IAA influx activity. In rice roots, OsNRT2.4 was expressed mainly in the base of lateral root primordia. Knockout of OsNRT2.4 decreased lateral root number and length, and the total N uptake per plant at both 0.25 and 2.5 mM NO3- levels. In the shoots, OsNRT2.4 was expressed mainly in vascular tissues, and its knockout decreased the growth and NO3--N distribution. Knockout of OsNRT2.4, however, did not affect rice growth and N uptake under conditions without N or with only NH4+ supply. We conclude that OsNRT2.4 functions as a dual-affinity nitrate transporter and is required for nitrate-regulated root and shoot growth of rice.
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Affiliation(s)
- Jia Wei
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
| | - Yi Zheng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
| | - Huimin Feng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
| | - Hongye Qu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
| | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
| | - Naoki Yamaji
- Institute of Plant Science and Resources, Okayama University, Japan
| | - Jian Feng Ma
- Institute of Plant Science and Resources, Okayama University, Japan
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, China
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10
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Li H, Yu M, Du XQ, Wang ZF, Wu WH, Quintero FJ, Jin XH, Li HD, Wang Y. NRT1.5/NPF7.3 Functions as a Proton-Coupled H +/K + Antiporter for K + Loading into the Xylem in Arabidopsis. THE PLANT CELL 2017; 29:2016-2026. [PMID: 28739644 PMCID: PMC5590498 DOI: 10.1105/tpc.16.00972] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 07/07/2017] [Accepted: 07/22/2017] [Indexed: 05/02/2023]
Abstract
Potassium and nitrogen are essential macronutrients for plant growth and have a positive impact on crop yield. Previous studies have indicated that the absorption and translocation of K+ and NO3- are correlated with each other in plants; however, the molecular mechanism that coordinates K+ and NO3- transport remains unknown. In this study, using a forward genetic approach, we isolated a low-K+-sensitive Arabidopsis thaliana mutant, lks2, that showed a leaf chlorosis phenotype under low-K+ conditions. LKS2 encodes the transporter NRT1.5/NPF7.3, a member of the NRT1/PTR (Nitrate Transporter 1/Peptide Transporter) family. The lks2/nrt1.5 mutants exhibit a remarkable defect in both K+ and NO3- translocation from root to shoot, especially under low-K+ conditions. This study demonstrates that LKS2 (NRT1.5) functions as a proton-coupled H+/K+ antiporter. Proton gradient can promote NRT1.5-mediated K+ release out of root parenchyma cells and facilitate K+ loading into the xylem. This study reveals that NRT1.5 plays a crucial role in K+ translocation from root to shoot and is also involved in the coordination of K+/NO3- distribution in plants.
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Affiliation(s)
- Hong Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Miao Yu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Xin-Qiao Du
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Zhi-Fang Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Wei-Hua Wu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Francisco J Quintero
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, 41092 Sevilla, Spain
| | - Xue-Hua Jin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Hao-Dong Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yi Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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11
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Hu R, Qiu D, Chen Y, Miller AJ, Fan X, Pan X, Zhang M. Knock-Down of a Tonoplast Localized Low-Affinity Nitrate Transporter OsNPF7.2 Affects Rice Growth under High Nitrate Supply. FRONTIERS IN PLANT SCIENCE 2016; 7:1529. [PMID: 27826301 PMCID: PMC5078692 DOI: 10.3389/fpls.2016.01529] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/29/2016] [Indexed: 05/19/2023]
Abstract
The large nitrate transporter 1/peptide transporter family (NPF) has been shown to transport diverse substrates, including nitrate, amino acids, peptides, phytohormones, and glucosinolates. However, the rice (Oryza sativa) root-specific family member OsNPF7.2 has not been functionally characterized. Here, our data show that OsNPF7.2 is a tonoplast localized low-affinity nitrate transporter, that affects rice growth under high nitrate supply. Expression analysis showed that OsNPF7.2 was mainly expressed in the elongation and maturation zones of roots, especially in the root sclerenchyma, cortex and stele. It was also induced by high concentrations of nitrate. Subcellular localization analysis showed that OsNPF7.2 was localized on the tonoplast of large and small vacuoles. Heterologous expression in Xenopus laevis oocytes suggested that OsNPF7.2 was a low-affinity nitrate transporter. Knock-down of OsNPF7.2 retarded rice growth under high concentrations of nitrate. Therefore, we deduce that OsNPF7.2 plays a role in intracellular allocation of nitrate in roots, and thus influences rice growth under high nitrate supply.
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Affiliation(s)
- Rui Hu
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of SciencesGuangzhou, China
- University of Chinese Academy of SciencesBeijing, China
| | - Diyang Qiu
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of SciencesGuangzhou, China
- University of Chinese Academy of SciencesBeijing, China
| | - Yi Chen
- Metabolic Biology Department, John Innes CentreNorwich, UK
| | | | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural UniversityNanjing, China
| | - Xiaoping Pan
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of SciencesGuangzhou, China
| | - Mingyong Zhang
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of SciencesGuangzhou, China
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12
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Braguy J, Zurbriggen MD. Synthetic strategies for plant signalling studies: molecular toolbox and orthogonal platforms. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:118-38. [PMID: 27227549 DOI: 10.1111/tpj.13218] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 05/11/2016] [Accepted: 05/13/2016] [Indexed: 05/15/2023]
Abstract
Plants deploy a wide array of signalling networks integrating environmental cues with growth, defence and developmental responses. The high level of complexity, redundancy and connection between several pathways hampers a comprehensive understanding of involved functional and regulatory mechanisms. The implementation of synthetic biology approaches is revolutionizing experimental biology in prokaryotes, yeasts and animal systems and can likewise contribute to a new era in plant biology. This review gives an overview on synthetic biology approaches for the development and implementation of synthetic molecular tools and techniques to interrogate, understand and control signalling events in plants, ranging from strategies for the targeted manipulation of plant genomes up to the spatiotemporally resolved control of gene expression using optogenetic approaches. We also describe strategies based on the partial reconstruction of signalling pathways in orthogonal platforms, like yeast, animal and in vitro systems. This allows a targeted analysis of individual signalling hubs devoid of interconnectivity with endogenous interacting components. Implementation of the interdisciplinary synthetic biology tools and strategies is not exempt of challenges and hardships but simultaneously most rewarding in terms of the advances in basic and applied research. As witnessed in other areas, these original theoretical-experimental avenues will lead to a breakthrough in the ability to study and comprehend plant signalling networks.
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Affiliation(s)
- Justine Braguy
- Institute of Synthetic Biology and CEPLAS, University of Düsseldorf, Universitätstrasse 1, Building 26.12.U1.25, Düsseldorf, 40225, Germany
- King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Matias D Zurbriggen
- Institute of Synthetic Biology and CEPLAS, University of Düsseldorf, Universitätstrasse 1, Building 26.12.U1.25, Düsseldorf, 40225, Germany
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13
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Atkinson N, Feike D, Mackinder LCM, Meyer MT, Griffiths H, Jonikas MC, Smith AM, McCormick AJ. Introducing an algal carbon-concentrating mechanism into higher plants: location and incorporation of key components. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1302-15. [PMID: 26538195 PMCID: PMC5102585 DOI: 10.1111/pbi.12497] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/18/2015] [Accepted: 09/29/2015] [Indexed: 05/13/2023]
Abstract
Many eukaryotic green algae possess biophysical carbon-concentrating mechanisms (CCMs) that enhance photosynthetic efficiency and thus permit high growth rates at low CO2 concentrations. They are thus an attractive option for improving productivity in higher plants. In this study, the intracellular locations of ten CCM components in the unicellular green alga Chlamydomonas reinhardtii were confirmed. When expressed in tobacco, all of these components except chloroplastic carbonic anhydrases CAH3 and CAH6 had the same intracellular locations as in Chlamydomonas. CAH6 could be directed to the chloroplast by fusion to an Arabidopsis chloroplast transit peptide. Similarly, the putative inorganic carbon (Ci) transporter LCI1 was directed to the chloroplast from its native location on the plasma membrane. CCP1 and CCP2 proteins, putative Ci transporters previously reported to be in the chloroplast envelope, localized to mitochondria in both Chlamydomonas and tobacco, suggesting that the algal CCM model requires expansion to include a role for mitochondria. For the Ci transporters LCIA and HLA3, membrane location and Ci transport capacity were confirmed by heterologous expression and H(14) CO3 (-) uptake assays in Xenopus oocytes. Both were expressed in Arabidopsis resulting in growth comparable with that of wild-type plants. We conclude that CCM components from Chlamydomonas can be expressed both transiently (in tobacco) and stably (in Arabidopsis) and retargeted to appropriate locations in higher plant cells. As expression of individual Ci transporters did not enhance Arabidopsis growth, stacking of further CCM components will probably be required to achieve a significant increase in photosynthetic efficiency in this species.
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Affiliation(s)
- Nicky Atkinson
- SynthSys & Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Doreen Feike
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Luke C M Mackinder
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Moritz T Meyer
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Howard Griffiths
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Martin C Jonikas
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Alison M Smith
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Alistair J McCormick
- SynthSys & Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich, UK
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14
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Xu D, Veres D, Belew Z, Olsen C, Nour-Eldin H, Halkier B. Functional Expression and Characterization of Plant ABC Transporters in Xenopus laevis Oocytes for Transport Engineering Purposes. Methods Enzymol 2016; 576:207-24. [DOI: 10.1016/bs.mie.2016.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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15
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Deshmukh RK, Sonah H, Bélanger RR. Plant Aquaporins: Genome-Wide Identification, Transcriptomics, Proteomics, and Advanced Analytical Tools. FRONTIERS IN PLANT SCIENCE 2016; 7:1896. [PMID: 28066459 PMCID: PMC5167727 DOI: 10.3389/fpls.2016.01896] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/30/2016] [Indexed: 05/02/2023]
Abstract
Aquaporins (AQPs) are channel-forming integral membrane proteins that facilitate the movement of water and many other small molecules. Compared to animals, plants contain a much higher number of AQPs in their genome. Homology-based identification of AQPs in sequenced species is feasible because of the high level of conservation of protein sequences across plant species. Genome-wide characterization of AQPs has highlighted several important aspects such as distribution, genetic organization, evolution and conserved features governing solute specificity. From a functional point of view, the understanding of AQP transport system has expanded rapidly with the help of transcriptomics and proteomics data. The efficient analysis of enormous amounts of data generated through omic scale studies has been facilitated through computational advancements. Prediction of protein tertiary structures, pore architecture, cavities, phosphorylation sites, heterodimerization, and co-expression networks has become more sophisticated and accurate with increasing computational tools and pipelines. However, the effectiveness of computational approaches is based on the understanding of physiological and biochemical properties, transport kinetics, solute specificity, molecular interactions, sequence variations, phylogeny and evolution of aquaporins. For this purpose, tools like Xenopus oocyte assays, yeast expression systems, artificial proteoliposomes, and lipid membranes have been efficiently exploited to study the many facets that influence solute transport by AQPs. In the present review, we discuss genome-wide identification of AQPs in plants in relation with recent advancements in analytical tools, and their availability and technological challenges as they apply to AQPs. An exhaustive review of omics resources available for AQP research is also provided in order to optimize their efficient utilization. Finally, a detailed catalog of computational tools and analytical pipelines is offered as a resource for AQP research.
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16
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Chen HY, Huh JH, Yu YC, Ho LH, Chen LQ, Tholl D, Frommer WB, Guo WJ. The Arabidopsis vacuolar sugar transporter SWEET2 limits carbon sequestration from roots and restricts Pythium infection. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 83:1046-58. [PMID: 26234706 DOI: 10.1111/tpj.12948] [Citation(s) in RCA: 134] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/17/2015] [Accepted: 07/20/2015] [Indexed: 05/04/2023]
Abstract
Plant roots secrete a significant portion of their assimilated carbon into the rhizosphere. The putative sugar transporter SWEET2 is highly expressed in Arabidopsis roots. Expression patterns of SWEET2-β-glucuronidase fusions confirmed that SWEET2 accumulates highly in root cells and thus may contribute to sugar secretion, specifically from epidermal cells of the root apex. SWEET2-green fluorescent protein fusions localized to the tonoplast, which engulfs the major sugar storage compartment. Functional analysis of SWEET2 activity in yeast showed low uptake activity for the glucose analog 2-deoxyglucose, consistent with a role in the transport of glucose across the tonoplast. Loss-of-function sweet2 mutants showed reduced tolerance to excess glucose, lower glucose accumulation in leaves, and 15-25% higher glucose-derived carbon efflux from roots, suggesting that SWEET2 has a role in preventing the loss of sugar from root tissue. SWEET2 root expression was induced more than 10-fold during Pythium infection. Importantly, sweet2 mutants were more susceptible to the oomycete, showing impaired growth after infection. We propose that root-expressed vacuolar SWEET2 modulates sugar secretion, possibly by reducing the availability of glucose sequestered in the vacuole, thereby limiting carbon loss to the rhizosphere. Moreover, the reduced availability of sugar in the rhizosphere due to SWEET2 activity contributes to resistance to Pythium.
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Affiliation(s)
- Hsin-Yi Chen
- Institute of Tropical Plant Science, National Cheng Kung University, Tainan City, 7013, Taiwan
| | - Jung-Hyun Huh
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Ya-Chi Yu
- Institute of Tropical Plant Science, National Cheng Kung University, Tainan City, 7013, Taiwan
| | - Li-Hsuan Ho
- Institute of Tropical Plant Science, National Cheng Kung University, Tainan City, 7013, Taiwan
| | - Li-Qing Chen
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Dorothea Tholl
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Wolf B Frommer
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Woei-Jiun Guo
- Institute of Tropical Plant Science, National Cheng Kung University, Tainan City, 7013, Taiwan
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
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17
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Xia X, Fan X, Wei J, Feng H, Qu H, Xie D, Miller AJ, Xu G. Rice nitrate transporter OsNPF2.4 functions in low-affinity acquisition and long-distance transport. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:317-31. [PMID: 25332358 DOI: 10.1093/jxb/eru425] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Plant proteins belonging to the NPF (formerly NRT1/PTR) family are well represented in every genome and function in transporting a wide variety of substrates. In this study, we showed that rice OsNPF2.4 is located in the plasma membrane and is expressed mainly in the epidermis, xylem parenchyma, and phloem companion cells. Functional analysis in oocytes showed that OsNPF2.4 is a pH-dependent, low-affinity NO₃⁻ transporter. Short-term (¹⁵NO₃⁻) influx rate, long-term NO₃⁻ acquisition by root, and upward transfer from root to shoot were decreased by disruption of OsNPF2.4 and increased by OsNPF2.4 overexpression under high NO₃⁻ supply. Moreover, the redistribution of NO₃⁻ in the mutants in comparison with the wild type from the oldest leaf to other organs, particularly to N-starved roots, was dramatically changed. Knockout of OsNPF2.4 decreased rice growth and potassium (K) concentration in xylem sap, root, culm, and sheath, but increased the shoot:root ratio of tissue K under higher NO₃⁻. We conclude that OsNPF2.4 functions in acquisition and long-distance transport of NO₃⁻ , and that altering its expression has an indirect effect on K recycling between the root and shoot.
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Affiliation(s)
- Xiudong Xia
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Jia Wei
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Huimin Feng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Hongye Qu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Dan Xie
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Anthony J Miller
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
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18
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Liu X, Huang D, Tao J, Miller AJ, Fan X, Xu G. Identification and functional assay of the interaction motifs in the partner protein OsNAR2.1 of the two-component system for high-affinity nitrate transport. THE NEW PHYTOLOGIST 2014; 204:74-80. [PMID: 25103875 PMCID: PMC4232926 DOI: 10.1111/nph.12986] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 07/15/2014] [Indexed: 05/21/2023]
Abstract
A partner protein, NAR2, is essential for high-affinity nitrate transport of the NRT2 protein in plants. However, the NAR2 motifs that interact with NRT2s for their plasma membrane (PM) localization and nitrate transporter activity have not been functionally characterized. In this study, OsNAR2.1 mutations with different carbon (C)-terminal deletions and nine different point mutations in the conserved regions of NAR2 homologs in plants were generated to explore the essential motifs involved in the interaction with OsNRT2.3a. Screening using the membrane yeast two-hybrid system and Xenopus oocytes for nitrogen-15 ((15)N) uptake demonstrated that either R100G or D109N point mutations impaired the OsNAR2.1 interaction with OsNRT2.3a. Western blotting and visualization using green fluorescent protein fused to either the N- or C-terminus of OsNAR2.1 indicated that OsNAR2.1 is expressed in both the PM and cytoplasm. The split-yellow fluorescent protein (YFP)/BiFC analyses indicated that OsNRT2.3a was targeted to the PM in the presence of OsNAR2.1, while either R100G or D109N mutation resulted in the loss of OsNRT2.3a-YFP signal in the PM. Based on these results, arginine 100 and aspartic acid 109 of the OsNAR2.1 protein are key amino acids in the interaction with OsNRT2.3a, and their interaction occurs in the PM but not cytoplasm.
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Affiliation(s)
- Xiaoqin Liu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural UniversityNanjing, 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural UniversityNanjing, 210095, China
| | - Daimin Huang
- MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural UniversityNanjing, 210095, China
| | - Jinyuan Tao
- MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural UniversityNanjing, 210095, China
| | - Anthony J Miller
- Metabolic Biology Department, John Innes CentreNorwich Research Park, Norwich, NR4 7UH, UK
| | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural UniversityNanjing, 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural UniversityNanjing, 210095, China
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural UniversityNanjing, 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural UniversityNanjing, 210095, China
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19
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Gu C, Zhang X, Jiang J, Guan Z, Zhao S, Fang W, Liao Y, Chen S, Chen F. Chrysanthemum CmNAR2 interacts with CmNRT2 in the control of nitrate uptake. Sci Rep 2014; 4:5833. [PMID: 25060485 PMCID: PMC5376060 DOI: 10.1038/srep05833] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/07/2014] [Indexed: 01/30/2023] Open
Abstract
Nitrate transporters are an important component of plant growth and development. Chrysanthemum morifolium is an important ornamental species, for which a sufficient supply of nitrogenous fertilizer is required to maintain economic yields. In this study, the full-length cDNA of the nitrate transporter genes CmNRT2 and CmNAR2 were isolated. CmNRT2 transcript accumulation was inducible by both nitrate and ammonium, but the latter ion down-regulated the transcript accumulation of CmNAR2. CmNRT2 might be a plasma membrane localized protein, while CmNAR2 was distributed throughout the cell. CmNAR2 was shown to interact with CmNRT2 by in vitro and in vivo assays. Arabidopsis thaliana plants heterologously expressing CmNRT2 showed an increased rate of nitrate influx, while this trait was unaltered in plants expressing CmNAR2. Double transformants (CmNRT2 plus CmNAR2) exhibited an enhanced rate of nitrate influx into the root. Our data indicated that the interaction of CmNAR2 with CmNRT2 contributed to the uptake of nitrate.
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Affiliation(s)
- Chunsun Gu
- 1] College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China [2] Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology &Equipment, Nanjing 210095, China
| | - Xiaoxue Zhang
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiafu Jiang
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhiyong Guan
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shuang Zhao
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Weimin Fang
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Yuan Liao
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Sumei Chen
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Fadi Chen
- 1] College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China [2] Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology &Equipment, Nanjing 210095, China
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