1
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Zheng S, Su M, Shi Z, Gao H, Ma C, Zhu S, Zhang L, Wu G, Wu W, Wang J, Zhang J, Zhang T. Exogenous sucrose influences KEA1 and KEA2 to regulate abscisic acid-mediated primary root growth in Arabidopsis. Plant Sci 2022; 317:111209. [PMID: 35193734 DOI: 10.1016/j.plantsci.2022.111209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/24/2022] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Arabidopsis K+-efflux antiporter (KEA)1 and KEA2 are chloroplast inner envelope membrane K+/H+ antiporters that play an important role in plastid development and seedling growth. However, the function of KEA1 and KEA2 during early seedling development is poorly understood. In this work, we found that in Arabidopsis, KEA1 and KEA2 mediated primary root growth by regulating photosynthesis and the ABA signaling pathway. Phenotypic analyses revealed that in the absence of sucrose, the primary root length of the kea1kea2 mutant was significantly shorter than that of the wild-type Columbia-0 (Col-0) plant. However, this phenotype could be remedied by the external application of sucrose. Meanwhile, HPLC-MS/MS results showed that in sucrose-free medium, ABA accumulation in the kea1kea2 mutant was considerably lower than that in Col-0. Transcriptome analysis revealed that many key genes involved in ABA signals were repressed in the kea1kea2 mutant. We concluded that KEA1 and KEA2 deficiency not only affected photosynthesis but was also involved in primary root growth likely through an ABA-dependent manner. This study confirmed the new function of KEA1 and KEA2 in affecting primary root growth.
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Affiliation(s)
- Sheng Zheng
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China; Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining 810016, China.
| | - Min Su
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Zhongfei Shi
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Haixia Gao
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Cheng Ma
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Shan Zhu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Lina Zhang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Guofan Wu
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Wangze Wu
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Juan Wang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Jinping Zhang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Tengguo Zhang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China.
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2
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Shan N, Zhang Y, Xu Y, Yuan X, Wan C, Chen C, Chen J, Gan Z. Ethylene-induced potassium transporter AcKUP2 gene is involved in kiwifruit postharvest ripening. BMC Plant Biol 2022; 22:108. [PMID: 35264115 PMCID: PMC8905847 DOI: 10.1186/s12870-022-03498-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/28/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Potassium (K) is important in the regulation of plant growth and development. It is the most abundant mineral element in kiwifruit, and its content increases during fruit ripening. However, how K+ transporter works in kiwifruit postharvest maturation is not yet clear. RESULTS Here, 12 K+ transporter KT/HAK/KUP genes, AcKUP1 ~ AcKUP12, were isolated from kiwifruit, and their phylogeny, genomic structure, chromosomal location, protein properties, conserved motifs and cis-acting elements were analysed. Transcription analysis revealed that AcKUP2 expression increased rapidly and was maintained at a high level during postharvest maturation, consistent with the trend of K content; AcKUP2 expression was induced by ethylene, suggesting that AcKUP2 might play a role in ripening. Fluorescence microscopy showed that AcKUP2 is localised in the plasma membrane. Cis-elements, including DER or ethylene response element (ERE) responsive to ethylene, were found in the AcKUP2 promoter sequence, and ethylene significantly enhanced the AcKUP2 promoter activity. Furthermore, we verified that AcERF15, an ethylene response factor, directly binds to the AcKUP2 promoter to promote its expression. Thus, AcKUP2 may be an important potassium transporter gene which involved in ethylene-regulated kiwifruit postharvest ripening. CONCLUSIONS Therefore, our study establishes the first genome-wide analysis of the kiwifruit KT/HAK/KUP gene family and provides valuable information for understanding the function of the KT/HAK/KUP genes in kiwifruit postharvest ripening.
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Affiliation(s)
- Nan Shan
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Yupei Zhang
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Yunhe Xu
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Xin Yuan
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Chunpeng Wan
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Chuying Chen
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Jinyin Chen
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China
- College of Materials and Chemical Engineering, Pingxiang University, Pingxiang, 330075, China
| | - Zengyu Gan
- Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China.
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3
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Ródenas R, Ragel P, Nieves-Cordones M, Martínez-Martínez A, Amo J, Lara A, Martínez V, Quintero FJ, Pardo JM, Rubio F. Insights into the mechanisms of transport and regulation of the arabidopsis high-affinity K+ transporter HAK51. Plant Physiol 2021; 185:1860-1874. [PMID: 33595056 PMCID: PMC8133630 DOI: 10.1093/plphys/kiab028] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 05/02/2023]
Abstract
The high-affinity K+ transporter HAK5 from Arabidopsis (Arabidopsis thaliana) is essential for K+ acquisition and plant growth at low micromolar K+ concentrations. Despite its functional relevance in plant nutrition, information about functional domains of HAK5 is scarce. Its activity is enhanced by phosphorylation via the AtCIPK23/AtCBL1-9 complex. Based on the recently published three-dimensionalstructure of the bacterial ortholog KimA from Bacillus subtilis, we have modeled AtHAK5 and, by a mutational approach, identified residues G67, Y70, G71, D72, D201, and E312 as essential for transporter function. According to the structural model, residues D72, D201, and E312 may bind K+, whereas residues G67, Y70, and G71 may shape the selective filter for K+, which resembles that of K+shaker-like channels. In addition, we show that phosphorylation of residue S35 by AtCIPK23 is required for reaching maximal transport activity. Serial deletions of the AtHAK5 C-terminus disclosed the presence of an autoinhibitory domain located between residues 571 and 633 together with an AtCIPK23-dependent activation domain downstream of position 633. Presumably, autoinhibition of AtHAK5 is counteracted by phosphorylation of S35 by AtCIPK23. Our results provide a molecular model for K+ transport and describe CIPK-CBL-mediated regulation of plant HAK transporters.
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Affiliation(s)
- Reyes Ródenas
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
- Present address: Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3, 24 chemin de Borde Rouge, 31320 Auzeville-Tolosane, France
| | - Paula Ragel
- Instituto de Bioquímica Vegetal y Fotosíntesis, cic-Cartuja, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla, 41092 Sevilla, Spain
- Present address: Centre for Organismal Studies (COS), Department of Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Manuel Nieves-Cordones
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
| | - Almudena Martínez-Martínez
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
| | - Jesús Amo
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
| | - Alberto Lara
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
| | - Vicente Martínez
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
| | - Francisco J Quintero
- Instituto de Bioquímica Vegetal y Fotosíntesis, cic-Cartuja, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla, 41092 Sevilla, Spain
| | - Jose M Pardo
- Instituto de Bioquímica Vegetal y Fotosíntesis, cic-Cartuja, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla, 41092 Sevilla, Spain
| | - Francisco Rubio
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain
- Author for communication:
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4
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Sánchez-McSweeney A, González-Gordo S, Aranda-Sicilia MN, Rodríguez-Rosales MP, Venema K, Palma JM, Corpas FJ. Loss of function of the chloroplast membrane K +/H + antiporters AtKEA1 and AtKEA2 alters the ROS and NO metabolism but promotes drought stress resilience. Plant Physiol Biochem 2021; 160:106-119. [PMID: 33485149 DOI: 10.1016/j.plaphy.2021.01.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 01/08/2021] [Indexed: 05/28/2023]
Abstract
Potassium (K+) exerts key physiological functions such as osmoregulation, stomatal movement, membrane transport, protein synthesis and photosynthesis among others. Previously, it was demonstrated in Arabidopsis thaliana that the loss of function of the chloroplast K+Efflux Antiporters KEA1 and KEA2, located in the inner envelope membrane, provokes inefficient photosynthesis. Therefore, the main goal of this study was to evaluate the potential impact of the loss of function of those cation transport systems in the metabolism of reactive oxygen and nitrogen species (ROS and RNS). Using 14-day-old seedlings from Arabidopsis double knock-out kea1kea2 mutants, ROS metabolism and NO content in roots and green cotyledons were studied at the biochemical level. The loss of function of AtKEA1 and AtKEA2 did not cause oxidative stress but it provoked an alteration of the ROS homeostasis affecting some ROS-generating enzymes. These included glycolate oxidase (GOX) and NADPH-dependent superoxide generation activity, enzymatic and non-enzymatic antioxidants and both NADP-isocitrate dehydrogenase and NADP-malic enzyme activities. NO content, analyzed by confocal laser scanning microscopy (CLSM), was negatively affected in both photosynthetic and non-photosynthetic organs in kea1kea2 mutant seedlings. Furthermore, the S-nitrosoglutathione reductase (GSNOR) protein expression and activity were downregulated in kea1kea2 mutants, whereas the tyrosine nitrated protein profile, analyzed by immunoblot, was unaffected but the relative expression of each immunoreactive band changed. Moreover, kea1kea2 mutants showed an increased photorespiratory pathway and stomata closure, thus promoting a higher resilience to drought stress. Data suggest that the chloroplast osmotic balance and integrity maintained by AtKEA1 and AtKEA2 are necessary to keep the balance of ROS/RNS metabolism. Moreover, these data open new questions about how endogenous NO generation might be affected by the K+/H+ transport located in the chloroplasts.
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Affiliation(s)
| | - Salvador González-Gordo
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Spain
| | - María Nieves Aranda-Sicilia
- Group of Ion Homeostasis, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental Del Zaidín, CSIC, C/ Profesor Albareda, 1, 18008, Granada, Spain
| | - María Pilar Rodríguez-Rosales
- Group of Ion Homeostasis, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental Del Zaidín, CSIC, C/ Profesor Albareda, 1, 18008, Granada, Spain
| | - Kees Venema
- Group of Ion Homeostasis, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental Del Zaidín, CSIC, C/ Profesor Albareda, 1, 18008, Granada, Spain
| | - José M Palma
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Spain
| | - Francisco J Corpas
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Spain.
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5
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Aranda Sicilia MN, Sánchez Romero ME, Rodríguez Rosales MP, Venema K. Plastidial transporters KEA1 and KEA2 at the inner envelope membrane adjust stromal pH in the dark. New Phytol 2021; 229:2080-2090. [PMID: 33111995 DOI: 10.1111/nph.17042] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/10/2020] [Indexed: 05/08/2023]
Abstract
Photosynthesis and carbon fixation depend critically on the regulation of pH in chloroplast compartments in the daylight and at night. While it is established that an alkaline stroma is required for carbon fixation, it is not known how alkaline stromal pH is formed, maintained or regulated. We tested whether two envelope transporters, AtKEA1 and AtKEA2, directly affected stromal pH in isolated Arabidopsis chloroplasts using the fluorescent probe 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF). External K+ -induced alkalinization of the stroma was observed in chloroplasts from wild-type (WT) plants but not from kea1kea2 mutants, suggesting that KEA1 and KEA2 mediate K+ uptake/H+ loss to modulate stromal pH. While light-stimulated alkalinization of the stroma was independent of KEA1 and KEA2, the rate of decay to neutral pH in the dark is delayed in kea1kea2 mutants. However, the dark-induced loss of a pH gradient across the thylakoid membrane was similar in WT and mutant chloroplasts. This indicates that proton influx from the cytosol mediated by envelope K+ /H+ antiporters contributes to adjustment of stromal pH upon light to dark transitions.
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Affiliation(s)
- María Nieves Aranda Sicilia
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, Granada, 18008, Spain
| | - María Elena Sánchez Romero
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, Granada, 18008, Spain
| | - María Pilar Rodríguez Rosales
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, Granada, 18008, Spain
| | - Kees Venema
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, Granada, 18008, Spain
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6
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Basso L, Yamori W, Szabo I, Shikanai T. Collaboration between NDH and KEA3 Allows Maximally Efficient Photosynthesis after a Long Dark Adaptation. Plant Physiol 2020; 184:2078-2090. [PMID: 32978277 PMCID: PMC7723091 DOI: 10.1104/pp.20.01069] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/16/2020] [Indexed: 05/10/2023]
Abstract
In angiosperms, the NADH dehydrogenase-like (NDH) complex mediates cyclic electron transport around PSI (CET). K+ Efflux Antiporter3 (KEA3) is a putative thylakoid H+/K+ antiporter and allows an increase in membrane potential at the expense of the ∆pH component of the proton motive force. In this study, we discovered that the chlororespiratory reduction2-1 (crr2-1) mutation, which abolished NDH-dependent CET, enhanced the kea3-1 mutant phenotypes in Arabidopsis (Arabidopsis thaliana). The NDH complex pumps protons during CET, further enhancing ∆pH, but its physiological function has not been fully clarified. The observed effect only took place upon exposure to light of 110 µmol photons m-2 s-1 after overnight dark adaptation. We propose two distinct modes of NDH action. In the initial phase, within 1 min after the onset of actinic light, the NDH-dependent CET engages with KEA3 to enhance electron transport efficiency. In the subsequent phase, in which the ∆pH-dependent down-regulation of the electron transport is relaxed, the NDH complex engages with KEA3 to relax the large ∆pH formed during the initial phase. We observed a similar impact of the crr2-1 mutation in the genetic background of the PROTON GRADIENT REGULATION5 overexpression line, in which the size of ∆pH was enhanced. When photosynthesis was induced at 300 µmol photons m-2 s-1, the contribution of KEA3 was negligible in the initial phase and the ∆pH-dependent down-regulation was not relaxed in the second phase. In the crr2-1 kea3-1 double mutant, the induction of CO2 fixation was delayed after overnight dark adaptation.
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Affiliation(s)
- Leonardo Basso
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502 Japan
| | - Wataru Yamori
- Institute for Sustainable Agro-Ecosystem Services, Graduate School of Agriculture and Life Science, University of Tokyo, Tokyo 188-0002 Japan
| | - Ildiko Szabo
- Department of Biology, University of Padova, 606-8502 Padova, Italy
| | - Toshiharu Shikanai
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502 Japan
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7
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Borjigin C, Schilling RK, Bose J, Hrmova M, Qiu J, Wege S, Situmorang A, Byrt C, Brien C, Berger B, Gilliham M, Pearson AS, Roy SJ. A single nucleotide substitution in TaHKT1;5-D controls shoot Na + accumulation in bread wheat. Plant Cell Environ 2020; 43:2158-2171. [PMID: 32652543 PMCID: PMC7540593 DOI: 10.1111/pce.13841] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 05/20/2020] [Accepted: 05/24/2020] [Indexed: 05/22/2023]
Abstract
Improving salinity tolerance in the most widely cultivated cereal, bread wheat (Triticum aestivum L.), is essential to increase grain yields on saline agricultural lands. A Portuguese landrace, Mocho de Espiga Branca accumulates up to sixfold greater leaf and sheath sodium (Na+ ) than two Australian cultivars, Gladius and Scout, under salt stress in hydroponics. Despite high leaf and sheath Na+ concentrations, Mocho de Espiga Branca maintained similar salinity tolerance compared to Gladius and Scout. A naturally occurring single nucleotide substitution was identified in the gene encoding a major Na+ transporter TaHKT1;5-D in Mocho de Espiga Branca, which resulted in a L190P amino acid residue variation. This variant prevents Mocho de Espiga Branca from retrieving Na+ from the root xylem leading to a high shoot Na+ concentration. The identification of the tissue-tolerant Mocho de Espiga Branca will accelerate the development of more elite salt-tolerant bread wheat cultivars.
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Affiliation(s)
- Chana Borjigin
- Australian Centre for Plant Functional Genomics, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Rhiannon K. Schilling
- Australian Centre for Plant Functional Genomics, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Jayakumar Bose
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Centre of Excellence in Plant Energy BiologyThe University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Maria Hrmova
- Australian Centre for Plant Functional Genomics, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Life Sciences, Huaiyin Normal UniversityHuai'anChina
| | - Jiaen Qiu
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Centre of Excellence in Plant Energy BiologyThe University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Stefanie Wege
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Centre of Excellence in Plant Energy BiologyThe University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Apriadi Situmorang
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Caitlin Byrt
- Division of Plant SciencesResearch School of Biology, Australian National UniversityActonAustralian Capital TerritoryAustralia
| | - Chris Brien
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- Australian Plant Phenomics FacilityThe Plant Accelerator, The University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Bettina Berger
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- Australian Plant Phenomics FacilityThe Plant Accelerator, The University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Matthew Gilliham
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Centre of Excellence in Plant Energy BiologyThe University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Allison S. Pearson
- Australian Centre for Plant Functional Genomics, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Centre of Excellence in Plant Energy BiologyThe University of AdelaideGlen OsmondSouth AustraliaAustralia
| | - Stuart J. Roy
- Australian Centre for Plant Functional Genomics, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- School of Agriculture, Food and Wine, The University of AdelaideGlen OsmondSouth AustraliaAustralia
- ARC Industrial Transformation Research Hub for Wheat in a Hot Dry Climate, The University of AdelaideGlen OsmondSouth AustraliaAustralia
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8
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Borjigin C, Schilling RK, Bose J, Hrmova M, Qiu J, Wege S, Situmorang A, Byrt C, Brien C, Berger B, Gilliham M, Pearson AS, Roy SJ. A single nucleotide substitution in TaHKT1;5-D controls shoot Na + accumulation in bread wheat. Plant Cell Environ 2020; 43:2158-2171. [PMID: 32652543 DOI: 10.1101/2020.01.21.909887] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 05/20/2020] [Accepted: 05/24/2020] [Indexed: 05/28/2023]
Abstract
Improving salinity tolerance in the most widely cultivated cereal, bread wheat (Triticum aestivum L.), is essential to increase grain yields on saline agricultural lands. A Portuguese landrace, Mocho de Espiga Branca accumulates up to sixfold greater leaf and sheath sodium (Na+ ) than two Australian cultivars, Gladius and Scout, under salt stress in hydroponics. Despite high leaf and sheath Na+ concentrations, Mocho de Espiga Branca maintained similar salinity tolerance compared to Gladius and Scout. A naturally occurring single nucleotide substitution was identified in the gene encoding a major Na+ transporter TaHKT1;5-D in Mocho de Espiga Branca, which resulted in a L190P amino acid residue variation. This variant prevents Mocho de Espiga Branca from retrieving Na+ from the root xylem leading to a high shoot Na+ concentration. The identification of the tissue-tolerant Mocho de Espiga Branca will accelerate the development of more elite salt-tolerant bread wheat cultivars.
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Affiliation(s)
- Chana Borjigin
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Rhiannon K Schilling
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Jayakumar Bose
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Maria Hrmova
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Life Sciences, Huaiyin Normal University, Huai'an, China
| | - Jiaen Qiu
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Stefanie Wege
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Apriadi Situmorang
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Caitlin Byrt
- Division of Plant Sciences, Research School of Biology, Australian National University, Acton, Australian Capital Territory, Australia
| | - Chris Brien
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- Australian Plant Phenomics Facility, The Plant Accelerator, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Bettina Berger
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- Australian Plant Phenomics Facility, The Plant Accelerator, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Matthew Gilliham
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Allison S Pearson
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Adelaide, Glen Osmond, South Australia, Australia
| | - Stuart J Roy
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Glen Osmond, South Australia, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia
- ARC Industrial Transformation Research Hub for Wheat in a Hot Dry Climate, The University of Adelaide, Glen Osmond, South Australia, Australia
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9
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Lara A, Ródenas R, Andrés Z, Martínez V, Quintero FJ, Nieves-Cordones M, Botella MA, Rubio F. Arabidopsis K+ transporter HAK5-mediated high-affinity root K+ uptake is regulated by protein kinases CIPK1 and CIPK9. J Exp Bot 2020; 71:5053-5060. [PMID: 32484219 PMCID: PMC7410179 DOI: 10.1093/jxb/eraa212] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 04/28/2020] [Indexed: 05/12/2023]
Abstract
The high-affinity K+ transporter HAK5 is the major contributor to root K+ uptake from dilute solutions in K+-starved Arabidopsis plants. Its functionality is tightly regulated and its activity is enhanced under K+ starvation by the transcriptional induction of the AtHAK5 gene, and by the activation of the transporter via the AtCBL1-AtCIPK23 complex. In the present study, the 26 members of the Arabidopsis CIPK protein kinase family were screened in yeast for their capacity to activate HAK5-mediated K+ uptake. Among them, AtCIPK1 was the most efficient activator of AtHAK5. In addition, AtCIPK9, previously reported to participate in K+ homeostasis, also activated the transporter. In roots, the genes encoding AtCIPK1 and AtCIPK9 were induced by K+ deprivation and atcipk1 and atcipk9 Arabidopsis KO mutants showed a reduced AtHAK5-mediated Rb+ uptake. Activation of AtHAK5 by AtCIPK1 did not occur under hyperosmotic stress conditions, where AtCIPK1 function has been shown to be required to maintain plant growth. Taken together, our data contribute to the identification of the complex regulatory networks that control the high-affinity K+ transporter AtHAK5 and root K+ uptake.
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Affiliation(s)
- Alberto Lara
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Campus de Espinardo, Murcia, Spain
| | - Reyes Ródenas
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Campus de Espinardo, Murcia, Spain
| | - Zaida Andrés
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
| | - Vicente Martínez
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Campus de Espinardo, Murcia, Spain
| | - Francisco J Quintero
- Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Universidad de Sevilla, Américo Vespucio, Sevilla, Spain
| | - Manuel Nieves-Cordones
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Campus de Espinardo, Murcia, Spain
| | - M Angeles Botella
- Departamento de Biología Aplicada, Universidad Miguel Hernández, Alicante, Spain
| | - Francisco Rubio
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Campus de Espinardo, Murcia, Spain
- Correspondence:
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10
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Bölter B, Mitterreiter MJ, Schwenkert S, Finkemeier I, Kunz HH. The topology of plastid inner envelope potassium cation efflux antiporter KEA1 provides new insights into its regulatory features. Photosynth Res 2020; 145:43-54. [PMID: 31865509 DOI: 10.1007/s11120-019-00700-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 12/11/2019] [Indexed: 05/25/2023]
Abstract
The plastid potassium cation efflux antiporters (KEAs) are important for chloroplast function, development, and photosynthesis. To understand their regulation at the protein level is therefore of fundamental importance. Prior studies have focused on the regulatory K+ transport and NAD-binding (KTN) domain in the C-terminus of the thylakoid carrier KEA3 but the localization of this domain remains unclear. While all three plastid KEA members are highly conserved in their transmembrane region and the C-terminal KTN domain, only the inner envelope KEA family members KEA1 and KEA2 carry a long soluble N-terminus. Interestingly, this region is acetylated at lysine 168 by the stromal acetyltransferase enzyme NSI. If an odd number of transmembrane domains existed for inner envelope KEAs, as it was suggested for all three plastid KEA carriers, regulatory domains and consequently protein regulation would occur on opposing sides of the inner envelope. In this study we therefore set out to investigate the topology of inner envelope KEA proteins. Using a newly designed antibody specific to the envelope KEA1 N-terminus and transgenic Arabidopsis plants expressing a C-terminal KEA1-YFP fusion protein, we show that both, the N-terminal and C-terminal, regulatory domains of KEA1 reside in the chloroplast stroma and not in the intermembrane space. Considering the high homology between KEA1 and KEA2, we therefore reason that envelope KEAs must consist of an even number of transmembrane domains.
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Affiliation(s)
- Bettina Bölter
- Dept. I, Plant Biochemistry, Ludwig Maximilians University Munich, Großhadernerstr. 2-4, 82152, Planegg-Martinsried, Germany
| | - Melanie J Mitterreiter
- Dept. I, Plant Biochemistry, Ludwig Maximilians University Munich, Großhadernerstr. 2-4, 82152, Planegg-Martinsried, Germany
| | - Serena Schwenkert
- Dept. I, Plant Biochemistry, Ludwig Maximilians University Munich, Großhadernerstr. 2-4, 82152, Planegg-Martinsried, Germany
| | - Iris Finkemeier
- Plant Physiology, Institute of Biology and Biotechnology of Plants, University of Muenster, Schlossplatz 7, 48149, Muenster, Germany
| | - Hans-Henning Kunz
- Plant Physiology, School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA, 99164-4236, USA.
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11
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Correa Galvis V, Strand DD, Messer M, Thiele W, Bethmann S, Hübner D, Uflewski M, Kaiser E, Siemiatkowska B, Morris BA, Tóth SZ, Watanabe M, Brückner F, Höfgen R, Jahns P, Schöttler MA, Armbruster U. H + Transport by K + EXCHANGE ANTIPORTER3 Promotes Photosynthesis and Growth in Chloroplast ATP Synthase Mutants. Plant Physiol 2020; 182:2126-2142. [PMID: 32041909 PMCID: PMC7140953 DOI: 10.1104/pp.19.01561] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 01/27/2020] [Indexed: 05/21/2023]
Abstract
The composition of the thylakoid proton motive force (pmf) is regulated by thylakoid ion transport. Passive ion channels in the thylakoid membrane dissipate the membrane potential (Δψ) component to allow for a higher fraction of pmf stored as a proton concentration gradient (ΔpH). K+/H+ antiport across the thylakoid membrane via K+ EXCHANGE ANTIPORTER3 (KEA3) instead reduces the ΔpH fraction of the pmf. Thereby, KEA3 decreases nonphotochemical quenching (NPQ), thus allowing for higher light use efficiency, which is particularly important during transitions from high to low light. Here, we show that in the background of the Arabidopsis (Arabidopsis thaliana) chloroplast (cp)ATP synthase assembly mutant cgl160, with decreased cpATP synthase activity and increased pmf amplitude, KEA3 plays an important role for photosynthesis and plant growth under steady-state conditions. By comparing cgl160 single with cgl160 kea3 double mutants, we demonstrate that in the cgl160 background loss of KEA3 causes a strong growth penalty. This is due to a reduced photosynthetic capacity of cgl160 kea3 mutants, as these plants have a lower lumenal pH than cgl160 mutants, and thus show substantially increased pH-dependent NPQ and decreased electron transport through the cytochrome b 6 f complex. Overexpression of KEA3 in the cgl160 background reduces pH-dependent NPQ and increases photosystem II efficiency. Taken together, our data provide evidence that under conditions where cpATP synthase activity is low, a KEA3-dependent reduction of ΔpH benefits photosynthesis and growth.
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Affiliation(s)
- Viviana Correa Galvis
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Deserah D Strand
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Michaela Messer
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Wolfram Thiele
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Stephanie Bethmann
- Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany
| | - Dennis Hübner
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Michal Uflewski
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Elias Kaiser
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Beata Siemiatkowska
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Bethan A Morris
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Szilvia Z Tóth
- Institute of Plant Biology, Biological Research Centre, Szeged, Temesvári krt 62, H-6726 Szeged, Hungary
| | - Mutsumi Watanabe
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Franziska Brückner
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Rainer Höfgen
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Peter Jahns
- Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany
| | - Mark Aurel Schöttler
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Ute Armbruster
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476 Potsdam, Germany
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12
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Wani SH, Kumar V, Khare T, Guddimalli R, Parveda M, Solymosi K, Suprasanna P, Kavi Kishor PB. Engineering salinity tolerance in plants: progress and prospects. Planta 2020; 251:76. [PMID: 32152761 DOI: 10.1007/s00425-020-03366-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 02/24/2020] [Indexed: 05/20/2023]
Abstract
There is a need to integrate conceptual framework based on the current understanding of salt stress responses with different approaches for manipulating and improving salt tolerance in crop plants. Soil salinity exerts significant constraints on global crop production, posing a serious challenge for plant breeders and biotechnologists. The classical transgenic approach for enhancing salinity tolerance in plants revolves by boosting endogenous defence mechanisms, often via a single-gene approach, and usually involves the enhanced synthesis of compatible osmolytes, antioxidants, polyamines, maintenance of hormone homeostasis, modification of transporters and/or regulatory proteins, including transcription factors and alternative splicing events. Occasionally, genetic manipulation of regulatory proteins or phytohormone levels confers salinity tolerance, but all these may cause undesired reduction in plant growth and/or yields. In this review, we present and evaluate novel and cutting-edge approaches for engineering salt tolerance in crop plants. First, we cover recent findings regarding the importance of regulatory proteins and transporters, and how they can be used to enhance salt tolerance in crop plants. We also evaluate the importance of halobiomes as a reservoir of genes that can be used for engineering salt tolerance in glycophytic crops. Additionally, the role of microRNAs as critical post-transcriptional regulators in plant adaptive responses to salt stress is reviewed and their use for engineering salt-tolerant crop plants is critically assessed. The potentials of alternative splicing mechanisms and targeted gene-editing technologies in understanding plant salt stress responses and developing salt-tolerant crop plants are also discussed.
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Affiliation(s)
- Shabir Hussain Wani
- Mountain Research Centre for Field Crops, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Khudwani, Anantnag, Jammu and Kashmir, 192 101, India.
| | - Vinay Kumar
- Department of Biotechnology, Modern College, Savitribai Phule Pune University, Ganeshkhind, Pune, 411 016, India
- Department of Environmental Science, Savitribai Phule Pune University, Ganeshkhind, Pune, 411 016, India
| | - Tushar Khare
- Department of Biotechnology, Modern College, Savitribai Phule Pune University, Ganeshkhind, Pune, 411 016, India
| | | | | | - Katalin Solymosi
- Department of Plant Anatomy, Institute of Biology, ELTE-Eötvös Loránd University, Budapest, 1053, Hungary
| | - Penna Suprasanna
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400 085, India
| | - P B Kavi Kishor
- Department of Biotechnology, Vignan's Foundation for Science Technology and Research, Vadlamudi, Guntur, 522 213, India
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13
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Nieves-Cordones M, Lara A, Ródenas R, Amo J, Rivero RM, Martínez V, Rubio F. Modulation of K + translocation by AKT1 and AtHAK5 in Arabidopsis plants. Plant Cell Environ 2019; 42:2357-2371. [PMID: 31046137 DOI: 10.1111/pce.13573] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/24/2019] [Accepted: 04/28/2019] [Indexed: 05/16/2023]
Abstract
Root cells take up K+ from the soil solution, and a fraction of the absorbed K+ is translocated to the shoot after being loaded into xylem vessels. K+ uptake and translocation are spatially separated processes. K+ uptake occurs in the cortex and epidermis whereas K+ translocation starts at the stele. Both uptake and translocation processes are expected to be linked, but the connection between them is not well characterized. Here, we studied K+ uptake and translocation using Rb+ as a tracer in wild-type Arabidopsis thaliana and in T-DNA insertion mutants in the K+ uptake or translocation systems. The relative amount of translocated Rb+ to the shoot was positively correlated with net Rb+ uptake rates, and the akt1 athak5 T-DNA mutant plants were more efficient in their allocation of Rb+ to shoots. Moreover, a mutation of SKOR and a reduced plant transpiration prevented the full upregulation of AtHAK5 gene expression and Rb+ uptake in K+ -starved plants. Lastly, Rb+ was found to be retrieved from root xylem vessels, with AKT1 playing a significant role in K+ -sufficient plants. Overall, our results suggest that K+ uptake and translocation are tightly coordinated via signals that regulate the expression of K+ transport systems.
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Affiliation(s)
- Manuel Nieves-Cordones
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Alberto Lara
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Reyes Ródenas
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Jesús Amo
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Rosa María Rivero
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Vicente Martínez
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
| | - Francisco Rubio
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Murcia, Spain
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14
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Santa-María GE, Oliferuk S, Moriconi JI. KT-HAK-KUP transporters in major terrestrial photosynthetic organisms: A twenty years tale. J Plant Physiol 2018; 226:77-90. [PMID: 29704646 DOI: 10.1016/j.jplph.2018.04.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 04/04/2018] [Accepted: 04/15/2018] [Indexed: 05/24/2023]
Abstract
Since their discovery, twenty years ago, KT-HAK-KUP transporters have become a keystone to understand how alkali cation fluxes are controlled in major land-dwelling photosynthetic organisms. In this review we focus on their discovery, phylogeny, and functions, as well as the regulation of its canonical member, AtHAK5. We also address issues related to structure-function studies, and the technological possibilities opened up by recent findings. Available evidence suggests that this family of transporters underwent an early divergence into major groups following the conquest of land by embryophytes. KT-HAK-KUPs are necessary to accomplish several major developmental and growth processes, as well as to ensure plant responses to environmental injuries. Although the primary function of these transporters is to mediate potassium (K+) fluxes, some of them can also mediate sodium (Na+) and cesium (Cs+) transport, and contribute to maintenance of K+ (and Na+) homeostasis in different plant tissues. In addition, there is evidence for a role of some members of this family in auxin movement and in adenylate cyclase activity. Recent research, focusing on the regulation of the canonical member of this family, AtHAK5, revealed the existence of a complex network that involves transcriptional and post-transcriptional phenomena which control the enhancement of AtHAK5-mediated K+ uptake when Arabidopsis thaliana plants are faced with low K+ supply. In spite of the formidable advances made since their discovery, important subjects remain to be elucidated to gain a more complete knowledge of the roles and regulation of KT-HAK-KUPs, as well as to improve their use for innovative procedures in crop breeding.
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Affiliation(s)
- Guillermo E Santa-María
- Instituto Tecnológico Chascomús (INTECH), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Universidad Nacional de San Martín (UNSAM), Avda Intendente Marino km 8, 2. Chascomús, 7130, Provincia de Buenos Aires, Argentina.
| | - Sonia Oliferuk
- Instituto Tecnológico Chascomús (INTECH), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Universidad Nacional de San Martín (UNSAM), Avda Intendente Marino km 8, 2. Chascomús, 7130, Provincia de Buenos Aires, Argentina
| | - Jorge I Moriconi
- Instituto Tecnológico Chascomús (INTECH), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Universidad Nacional de San Martín (UNSAM), Avda Intendente Marino km 8, 2. Chascomús, 7130, Provincia de Buenos Aires, Argentina
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15
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Sze H, Chanroj S. Plant Endomembrane Dynamics: Studies of K +/H + Antiporters Provide Insights on the Effects of pH and Ion Homeostasis. Plant Physiol 2018; 177:875-895. [PMID: 29691301 PMCID: PMC6053008 DOI: 10.1104/pp.18.00142] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/04/2018] [Indexed: 05/17/2023]
Abstract
Plants remodel their cells through the dynamic endomembrane system. Intracellular pH is important for membrane trafficking, but the determinants of pH homeostasis are poorly defined in plants. Electrogenic proton (H+) pumps depend on counter-ion fluxes to establish transmembrane pH gradients at the plasma membrane and endomembranes. Vacuolar-type H+-ATPase-mediated acidification of the trans-Golgi network is crucial for secretion and membrane recycling. Pump and counter-ion fluxes are unlikely to fine-tune pH; rather, alkali cation/H+ antiporters, which can alter pH and/or cation homeostasis locally and transiently, are prime candidates. Plants have a large family of predicted cation/H+ exchangers (CHX) of obscure function, in addition to the well-studied K+(Na+)/H+ exchangers (NHX). Here, we review the regulation of cytosolic and vacuolar pH, highlighting the similarities and distinctions of NHX and CHX members. In planta, alkalinization of the trans-Golgi network or vacuole by NHXs promotes membrane trafficking, endocytosis, cell expansion, and growth. CHXs localize to endomembranes and/or the plasma membrane and contribute to male fertility, pollen tube guidance, pollen wall construction, stomatal opening, and, in soybean (Glycine max), tolerance to salt stress. Three-dimensional structural models and mutagenesis of Arabidopsis (Arabidopsis thaliana) genes have allowed us to infer that AtCHX17 and AtNHX1 share a global architecture and a translocation core like bacterial Na+/H+ antiporters. Yet, the presence of distinct residues suggests that some CHXs differ from NHXs in pH sensing and electrogenicity. How H+ pumps, counter-ion fluxes, and cation/H+ antiporters are linked with signaling and membrane trafficking to remodel membranes and cell walls awaits further investigation.
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Affiliation(s)
- Heven Sze
- Department of Cell Biology and Molecular Genetics and Department of Plant Science and Landscape Architecture, University of Maryland, College Park, Maryland 20742
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Salil Chanroj
- Department of Biotechnology, Burapha University, Chon-Buri 20131, Thailand
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16
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De Luca A, Pardo JM, Leidi EO. Pleiotropic effects of enhancing vacuolar K/H exchange in tomato. Physiol Plant 2018; 163:88-102. [PMID: 29076168 DOI: 10.1111/ppl.12656] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 10/11/2017] [Accepted: 10/23/2017] [Indexed: 05/27/2023]
Abstract
Cation antiporters of the NHX family are widely regarded as determinants of salt tolerance due to their capacity to drive sodium (Na) and sequester it into vacuoles. Recent work shows, however, that NHX transporters are primarily involved in vacuolar potassium (K) storage. Over-expression of the K/H antiporter AtNHX1 in tomato increases K accumulation into vacuoles and plant sensitivity to K deprivation. Here we show that the appearance of early leaf symptoms of K deficiency was associated with higher concentration of polyamines. Transgenic roots exhibited a greater sensitivity than shoots to K deprivation with changes in the composition of the free amino acids pool, total sugars and organic acids. Concentrations of amides (glutamine), amino acids (arginine) and sugars significantly increased in root, together with a reduction in malate and succinate concentrations. The concentration of pyruvate and the activity of pyruvate kinase were greater in the transgenic roots before K withdrawal although both parameters were depressed by K deprivation and approached wild-type levels. In the longer term, the over-expression of the NHX1 antiporter affected root growth and biomass partitioning (shoot/root ratio). Greater ethylene release produced longer stem internodes and leaf curling in the transgenic line. Our data show that enhanced sequestration of K by the NHX antiporter in the vacuoles altered cellular K homeostasis and had deeper physiological consequences than expected. Early metabolic changes lead later on to profound morphological and physiological adjustments resulting eventually in the loss of nutrient use efficiency.
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Affiliation(s)
- Anna De Luca
- Department of Plant Biotechnology, IRNAS-CSIC, Reina Mercedes 10, Seville, 41012, Spain
| | - José M Pardo
- Institute of Plant Biochemistry and Photosynthesis, IBVF-CSIC, Americo Vespucio 49, Seville, 41092, Spain
| | - Eduardo O Leidi
- Department of Plant Biotechnology, IRNAS-CSIC, Reina Mercedes 10, Seville, 41012, Spain
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17
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Wang C, Yamamoto H, Narumiya F, Munekage YN, Finazzi G, Szabo I, Shikanai T. Fine-tuned regulation of the K + /H + antiporter KEA3 is required to optimize photosynthesis during induction. Plant J 2017; 89:540-553. [PMID: 27783435 DOI: 10.1111/tpj.13405] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 05/22/2023]
Abstract
KEA3 is a thylakoid membrane localized K+ /H+ antiporter that regulates photosynthesis by modulating two components of proton motive force (pmf), the proton gradient (∆pH) and the electric potential (∆ψ). We identified a mutant allele of KEA3, disturbed proton gradient regulation (dpgr) based on its reduced non-photochemical quenching (NPQ) in artificial (CO2 -free with low O2 ) air. This phenotype was enhanced in the mutant backgrounds of PSI cyclic electron transport (pgr5 and crr2-1). In ambient air, reduced NPQ was observed during induction of photosynthesis in dpgr, the phenotype that was enhanced after overnight dark adaptation. In contrast, the knockout allele of kea3-1 exhibited a high-NPQ phenotype during steady state in ambient air. Consistent with this kea3-1 phenotype in ambient air, the membrane topology of KEA3 indicated a proton efflux from the thylakoid lumen to the stroma. The dpgr heterozygotes showed a semidominant and dominant phenotype in artificial and ambient air, respectively. In dpgr, the protein level of KEA3 was unaffected but the downregulation of its activity was probably disturbed. Our findings suggest that fine regulation of KEA3 activity is necessary for optimizing photosynthesis.
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Affiliation(s)
- Caijuan Wang
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
| | - Hiroshi Yamamoto
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
- CREST, Japan Science and Technology Agency, Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Fumika Narumiya
- Graduate School of Sciences, Nara Institute of Science and Technology, Ikoma, Nara, 630-0101, Japan
- Sakai City Institute of Public Health, Sakai, Osaka, 590-0953, Japan
| | - Yuri Nakajima Munekage
- Graduate School of Sciences, Nara Institute of Science and Technology, Ikoma, Nara, 630-0101, Japan
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Sandan, Hyogo, 669-1337, Japan
| | - Giovanni Finazzi
- UMR 5168 Laboratoire de Physiologie Cellulaire Végétale (LPCV) CNRS/UJF/INRA/CEA, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), CEA Grenoble, 38054, Grenoble, France
| | - Ildiko Szabo
- Department of Biology, University of Padova, Padova, 35121, Italy
| | - Toshiharu Shikanai
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
- CREST, Japan Science and Technology Agency, Chiyoda-ku, Tokyo, 102-0076, Japan
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Zhao S, Zhang ML, Ma TL, Wang Y. Phosphorylation of ARF2 Relieves Its Repression of Transcription of the K+ Transporter Gene HAK5 in Response to Low Potassium Stress. Plant Cell 2016; 28:3005-3019. [PMID: 27895227 PMCID: PMC5240742 DOI: 10.1105/tpc.16.00684] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/01/2016] [Accepted: 11/28/2016] [Indexed: 05/19/2023]
Abstract
Potassium (K+) plays crucial roles in plant growth and development. In natural environments, K+ availability in soils is relatively low and fluctuating. Transcriptional regulation of K+ transporter genes is one of the most important mechanisms in the plant's response to K+ deficiency. In this study, we demonstrated that the transcription factor ARF2 (Auxin Response Factor 2) modulates the expression of the K+ transporter gene HAK5 (High Affinity K+ transporter 5) in Arabidopsis thaliana The arf2 mutant plants showed a tolerant phenotype similar to the HAK5-overexpressing lines on low-K+ medium, whose primary root lengths were longer than those of wild-type plants. High-affinity K+ uptake was significantly increased in these plants. ARF2-overexpressing lines and the hak5 mutant were both sensitive to low-K+ stress. Disruption of HAK5 in the arf2 mutant abolished the low-K+-tolerant phenotype of arf2 As a transcriptional repressor, ARF2 directly bound to the HAK5 promoter and repressed HAK5 expression under K+ sufficient conditions. ARF2 can be phosphorylated after low-K+ treatment, which abolished its DNA binding activity to the HAK5 promoter and relieved the inhibition on HAK5 transcription. Therefore, HAK5 transcript could be induced, and HAK5-mediated high-affinity K+ uptake was enhanced under K+ deficient conditions. The presented results demonstrate that ARF2 plays important roles in the response to external K+ supply in Arabidopsis and regulates HAK5 transcription accordingly.
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Affiliation(s)
- Shuai Zhao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Mei-Ling Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Tian-Li Ma
- 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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Aranda-Sicilia MN, Aboukila A, Armbruster U, Cagnac O, Schumann T, Kunz HH, Jahns P, Rodríguez-Rosales MP, Sze H, Venema K. Envelope K+/H+ Antiporters AtKEA1 and AtKEA2 Function in Plastid Development. Plant Physiol 2016; 172:441-9. [PMID: 27443603 PMCID: PMC5074627 DOI: 10.1104/pp.16.00995] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 07/19/2016] [Indexed: 05/04/2023]
Abstract
It is well established that thylakoid membranes of chloroplasts convert light energy into chemical energy, yet the development of chloroplast and thylakoid membranes is poorly understood. Loss of function of the two envelope K(+)/H(+) antiporters AtKEA1 and AtKEA2 was shown previously to have negative effects on the efficiency of photosynthesis and plant growth; however, the molecular basis remained unclear. Here, we tested whether the previously described phenotypes of double mutant kea1kea2 plants are due in part to defects during early chloroplast development in Arabidopsis (Arabidopsis thaliana). We show that impaired growth and pigmentation is particularly evident in young expanding leaves of kea1kea2 mutants. In proliferating leaf zones, chloroplasts contain much lower amounts of photosynthetic complexes and chlorophyll. Strikingly, AtKEA1 and AtKEA2 proteins accumulate to high amounts in small and dividing plastids, where they are specifically localized to the two caps of the organelle separated by the fission plane. The unusually long amino-terminal domain of 550 residues that precedes the antiport domain appears to tether the full-length AtKEA2 protein to the two caps. Finally, we show that the double mutant contains 30% fewer chloroplasts per cell. Together, these results show that AtKEA1 and AtKEA2 transporters in specific microdomains of the inner envelope link local osmotic, ionic, and pH homeostasis to plastid division and thylakoid membrane formation.
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Affiliation(s)
- María Nieves Aranda-Sicilia
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Ali Aboukila
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Ute Armbruster
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Olivier Cagnac
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Tobias Schumann
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Hans-Henning Kunz
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Peter Jahns
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - María Pilar Rodríguez-Rosales
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Heven Sze
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
| | - Kees Venema
- Departimento de Bioquímica, Biología Celular, y Molecular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain (M.N.A.-S., A.A., O.C., M.P.R.-R., K.V.);Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, California 94720 (U.A.);Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, D-40225 Duesseldorf, Germany (T.S., P.J.);School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 (H.-H.K.); andDepartment of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742 (H.S.)
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Wang C, Xu W, Jin H, Zhang T, Lai J, Zhou X, Zhang S, Liu S, Duan X, Wang H, Peng C, Yang C. A Putative Chloroplast-Localized Ca(2+)/H(+) Antiporter CCHA1 Is Involved in Calcium and pH Homeostasis and Required for PSII Function in Arabidopsis. Mol Plant 2016; 9:1183-1196. [PMID: 27302341 DOI: 10.1016/j.molp.2016.05.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/25/2016] [Accepted: 05/30/2016] [Indexed: 05/18/2023]
Abstract
Calcium is important for chloroplast, not only in its photosynthetic but also nonphotosynthetic functions. Multiple Ca(2+)/H(+) transporters and channels have been described and studied in the plasma membrane and organelle membranes of plant cells; however, the molecular identity and physiological roles of chloroplast Ca(2+)/H(+) antiporters have remained unknown. Here we report the identification and characterization of a member of the UPF0016 family, CCHA1 (a chloroplast-localized potential Ca(2+)/H(+) antiporter), in Arabidopsis thaliana. We observed that the ccha1 mutant plants developed pale green leaves and showed severely stunted growth along with impaired photosystem II (PSII) function. CCHA1 localizes to the chloroplasts, and the levels of the PSII core subunits and the oxygen-evolving complex were significantly decreased in the ccha1 mutants compared with the wild type. In high Ca(2+) concentrations, Arabidopsis CCHA1 partially rescued the growth defect of yeast gdt1Δ null mutant, which is defective in a Ca(2+)/H(+) antiporter. The ccha1 mutant plants also showed significant sensitivity to high concentrations of CaCl2 and MnCl2, as well as variation in pH. Taken these results together, we propose that CCHA1 might encode a putative chloroplast-localized Ca(2+)/H(+) antiporter with critical functions in the regulation of PSII and in chloroplast Ca(2+) and pH homeostasis in Arabidopsis.
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Affiliation(s)
- Chao Wang
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Weitao Xu
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Honglei Jin
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Taijie Zhang
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Jianbin Lai
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Xuan Zhou
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Shengchun Zhang
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Shengjie Liu
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Xuewu Duan
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong Province 510650, China
| | - Hongbin Wang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Changlian Peng
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China
| | - Chengwei Yang
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou 510631, China.
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21
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Liu L, Zheng C, Kuang B, Wei L, Yan L, Wang T. Receptor-Like Kinase RUPO Interacts with Potassium Transporters to Regulate Pollen Tube Growth and Integrity in Rice. PLoS Genet 2016; 12:e1006085. [PMID: 27447945 PMCID: PMC4957769 DOI: 10.1371/journal.pgen.1006085] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 05/06/2016] [Indexed: 11/18/2022] Open
Abstract
During sexual reproduction of flowering plants, the pollen tube grows fast and over a long distance within the pistil to deliver two sperms for double fertilization. Growing plant cells need to communicate constantly with external stimuli as well as monitor changes in surface tension of the cell wall and plasma membrane to coordinate these signals and internal growth machinery; however, the underlying mechanisms remain largely unknown. Here we show that the rice member of plant-specific receptor-like kinase CrRLK1Ls subfamily, Ruptured Pollen tube (RUPO), is specifically expressed in rice pollen. RUPO localizes to the apical plasma membrane and vesicle of pollen tubes and is required for male gamete transmission. K+ levels were greater in pollen of homozygous CRISPR-knockout lines than wild-type plants, and pollen tubes burst shortly after germination. We reveal the interaction of RUPO with high-affinity potassium transporters. Phosphorylation of RUPO established and dephosphorylation abolished the interaction. These results have revealed the receptor-like kinase as a regulator of high-affinity potassium transporters via phosphorylation-dependent interaction, and demonstrated a novel receptor-like kinase signaling pathway that mediates K+ homeostasis required for pollen tube growth and integrity.
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Affiliation(s)
- Lingtong Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Canhui Zheng
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Baijan Kuang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Liqin Wei
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Longfeng Yan
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Tai Wang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- * E-mail:
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22
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Armbruster U, Leonelli L, Correa Galvis V, Strand D, Quinn EH, Jonikas MC, Niyogi KK. Regulation and Levels of the Thylakoid K+/H+ Antiporter KEA3 Shape the Dynamic Response of Photosynthesis in Fluctuating Light. Plant Cell Physiol 2016; 57:1557-1567. [PMID: 27335350 PMCID: PMC4937787 DOI: 10.1093/pcp/pcw085] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/24/2016] [Indexed: 05/22/2023]
Abstract
Crop canopies create environments of highly fluctuating light intensities. In such environments, photoprotective mechanisms and their relaxation kinetics have been hypothesized to limit photosynthetic efficiency and therefore crop yield potential. Here, we show that overexpression of the Arabidopsis thylakoid K+/H+ antiporter KEA3 accelerates the relaxation of photoprotective energy-dependent quenching after transitions from high to low light in Arabidopsis and tobacco. This, in turn, enhances PSII quantum efficiency in both organisms, supporting that in wild-type plants, residual light energy quenching following a high to low light transition represents a limitation to photosynthetic efficiency in fluctuating light. This finding underscores the potential of accelerating quenching relaxation as a building block for improving photosynthetic efficiency in the field. Additionally, by overexpressing natural KEA3 variants with modification to the C-terminus, we show that KEA3 activity is regulated by a mechanism involving its lumen-localized C-terminus, which lowers KEA3 activity in high light. This regulatory mechanism fine-tunes the balance between photoprotective energy dissipation in high light and maximum quantum yield in low light, likely to be critical for efficient photosynthesis in fluctuating light conditions.
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Affiliation(s)
- Ute Armbruster
- Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
- Carnegie Institution for Science, Department of Plant Biology, Stanford, CA 94305, USA
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Potsdam, Germany
| | - Lauriebeth Leonelli
- Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Viviana Correa Galvis
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Potsdam, Germany
| | - Deserah Strand
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Potsdam, Germany
| | - Erica H Quinn
- Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Martin C Jonikas
- Carnegie Institution for Science, Department of Plant Biology, Stanford, CA 94305, USA
| | - Krishna K Niyogi
- Howard Hughes Medical Institute, Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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23
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Ariyarathna HACK, Oldach KH, Francki MG. A comparative gene analysis with rice identified orthologous group II HKT genes and their association with Na(+) concentration in bread wheat. BMC Plant Biol 2016; 16:21. [PMID: 26786911 PMCID: PMC4719669 DOI: 10.1186/s12870-016-0714-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 01/14/2016] [Indexed: 05/08/2023]
Abstract
BACKGROUND Although the HKT transporter genes ascertain some of the key determinants of crop salt tolerance mechanisms, the diversity and functional role of group II HKT genes are not clearly understood in bread wheat. The advanced knowledge on rice HKT and whole genome sequence was, therefore, used in comparative gene analysis to identify orthologous wheat group II HKT genes and their role in trait variation under different saline environments. RESULTS The four group II HKTs in rice identified two orthologous gene families from bread wheat, including the known TaHKT2;1 gene family and a new distinctly different gene family designated as TaHKT2;2. A single copy of TaHKT2;2 was found on each homeologous chromosome arm 7AL, 7BL and 7DL and each gene was expressed in leaf blade, sheath and root tissues under non-stressed and at 200 mM salt stressed conditions. The proteins encoded by genes of the TaHKT2;2 family revealed more than 93% amino acid sequence identity but ≤52% amino acid identity compared to the proteins encoded by TaHKT2;1 family. Specifically, variations in known critical domains predicted functional differences between the two protein families. Similar to orthologous rice genes on chromosome 6L, TaHKT2;1 and TaHKT2;2 genes were located approximately 3 kb apart on wheat chromosomes 7AL, 7BL and 7DL, forming a static syntenic block in the two species. The chromosomal region on 7AL containing TaHKT2;1 7AL-1 co-located with QTL for shoot Na(+) concentration and yield in some saline environments. CONCLUSION The differences in copy number, genes sequences and encoded proteins between TaHKT2;2 homeologous genes and other group II HKT gene families within and across species likely reflect functional diversity for ion selectivity and transport in plants. Evidence indicated that neither TaHKT2;2 nor TaHKT2;1 were associated with primary root Na(+) uptake but TaHKT2;1 may be associated with trait variation for Na(+) exclusion and yield in some but not all saline environments.
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Affiliation(s)
- H A Chandima K Ariyarathna
- School of Plant Biology and Institute of Agriculture, The University of Western Australia, Crawley, 6009, Western Australia.
- State Agricultural Biotechnology Centre, Murdoch University, Murdoch, 6150, Western Australia.
| | - Klaus H Oldach
- South Australia Research Development Institute, Plant Genomics Centre, Waite Research Precinct, Urrbrae, 5064, South Australia.
| | - Michael G Francki
- State Agricultural Biotechnology Centre, Murdoch University, Murdoch, 6150, Western Australia.
- Department of Agriculture and Food Western Australia, South Perth, 6151, Western Australia.
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24
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Ragel P, Ródenas R, García-Martín E, Andrés Z, Villalta I, Nieves-Cordones M, Rivero RM, Martínez V, Pardo JM, Quintero FJ, Rubio F. The CBL-Interacting Protein Kinase CIPK23 Regulates HAK5-Mediated High-Affinity K+ Uptake in Arabidopsis Roots. Plant Physiol 2015; 169:2863-73. [PMID: 26474642 PMCID: PMC4677917 DOI: 10.1104/pp.15.01401] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/16/2015] [Indexed: 05/18/2023]
Abstract
Plant growth and development requires efficient acquisition of essential elements. Potassium (K(+)) is an important macronutrient present in the soil solution at a wide range of concentrations. Regulation of the K(+) uptake systems in the roots is essential to secure K(+) supply. It has been shown in Arabidopsis (Arabidopsis thaliana) that when the external K(+) concentration is very low (<10 µm), K(+) nutrition depends exclusively on the high-affinity K(+) transporter5 (HAK5). Low-K(+)-induced transcriptional activation of the gene encoding HAK5 has been previously reported. Here, we show the posttranscriptional regulation of HAK5 transport activity by phosphorylation. Expression in a heterologous system showed that the Ca(2+) sensors calcineurin B-like (CBL1), CBL8, CBL9, and CBL10, together with CBL-interacting protein kinase23 (CIPK23), activated HAK5 in vivo. This activation produced an increase in the affinity and the Vmax of K(+) transport. In vitro experiments show that the N terminus of HAK5 is phosphorylated by CIPK23. This supports the idea that phosphorylation of HAK5 induces a conformational change that increases its affinity for K(+). Experiments of K(+) (Rb(+)) uptake and growth measurements in low-K(+) medium with Arabidopsis single mutants hak5, akt1, and cipk23, double mutants hak5 akt1, hak5 cipk23, and akt1 cipk23, and the triple mutant hak5 akt1 cipk23 confirmed the regulatory role of CIPK23 in planta.
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Affiliation(s)
- Paula Ragel
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Reyes Ródenas
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Elena García-Martín
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Zaida Andrés
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Irene Villalta
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Manuel Nieves-Cordones
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Rosa M Rivero
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Vicente Martínez
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Jose M Pardo
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Francisco J Quintero
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
| | - Francisco Rubio
- Departamento de Biotecnología Vegetal, Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Sevilla E-41012, Spain (P.R., E.G.-M., Z.A., I.V., J.M.P., F.J.Q.);Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, Murcia 30100, Spain (R.R., R.M.R., V.M., F.R.); andBiochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, Unité Mixte de Recherche 5004 Centre National de la Recherche Scientifique/Unité Mixte de Recherche 0386 Institut National de la Recherche Agronomique/Montpellier SupAgro/Université Montpellier 2, 34060 Montpellier cedex 2, France (M.N.-C.)
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25
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Sun Y, Kong X, Li C, Liu Y, Ding Z. Potassium Retention under Salt Stress Is Associated with Natural Variation in Salinity Tolerance among Arabidopsis Accessions. PLoS One 2015; 10:e0124032. [PMID: 25993093 PMCID: PMC4438003 DOI: 10.1371/journal.pone.0124032] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 02/27/2015] [Indexed: 01/09/2023] Open
Abstract
Plants are exposed to various environmental stresses during their life cycle such as salt, drought and cold. Natural variation mediated plant growth adaptation has been employed as an effective approach in response to the diverse environmental cues such as salt stress. However, the molecular mechanism underlying this process is not well understood. In the present study, a collection of 82 Arabidopsis thaliana accessions (ecotypes) was screened with a view to identify variation for salinity tolerance. Seven accessions showed a higher level of tolerance than Col-0. The young seedlings of the tolerant accessions demonstrated a higher K(+) content and a lower Na(+)/K(+) ratio when exposed to salinity stress, but its Na(+) content was the same as that of Col-0. The K(+) transporter genes AtHAK5, AtCHX17 and AtKUP1 were up-regulated significantly in almost all the tolerant accessions, even in the absence of salinity stress. There was little genetic variation or positive transcriptional variation between the selections and Col-0 with respect to Na+-related transporter genes, as AtSOS genes, AtNHX1 and AtHKT1;1. In addition, under salinity stress, these selections accumulated higher compatible solutes and lower reactive oxygen species than did Col-0. Taken together, our results showed that natural variation in salinity tolerance of Arabidopsis seems to have been achieved by the strong capacity of K(+) retention.
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Affiliation(s)
- Yanling Sun
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Xiangpei Kong
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Cuiling Li
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Yongxiu Liu
- The Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, 100093, Beijing, China
| | - Zhaojun Ding
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
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26
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Li G, Xu W, Kronzucker HJ, Shi W. Ethylene is critical to the maintenance of primary root growth and Fe homeostasis under Fe stress in Arabidopsis. J Exp Bot 2015; 66:2041-54. [PMID: 25711703 PMCID: PMC4378635 DOI: 10.1093/jxb/erv005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 12/16/2014] [Accepted: 12/19/2014] [Indexed: 05/18/2023]
Abstract
Iron (Fe) is an essential microelement but is highly toxic when in excess. The response of plant roots to Fe toxicity and the nature of the regulatory pathways engaged are poorly understood. Here, we examined the response to excess Fe exposure in Arabidopsis wild type and ethylene mutants with a focus on primary root growth and the role of ethylene. We showed that excess Fe arrested primary root growth by decreasing both cell elongation and division, and principally resulteds from direct external Fe contact at the root tip. Pronounced ethylene, but not abscisic acid, evolution was associated with excess Fe exposure. Ethylene antagonists intensified root growth inhibition in the wild type, while the inhibition was significantly reduced in ethylene-overproduction mutants. We showed that ethylene plays a positive role in tissue Fe homeostasis, even in the absence of iron-plaque formation. Ethylene reduced Fe concentrations in the stele, xylem, and shoot. Furthermore, ethylene increased the expression of genes encoding Fe-sequestering ferritins. Additionally, ethylene significantly enhanced root K(+) status and upregulated K(+)-transporter (HAK5) expression. Our findings highlight the important role of ethylene in tissue Fe and K homeostasis and primary root growth under Fe stress in Arabidopsis.
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Affiliation(s)
- Guangjie Li
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, PR China
| | - Weifeng Xu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, PR China
| | - Herbert J Kronzucker
- Department of Biological Sciences, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Weiming Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, PR China
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27
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Daras G, Rigas S, Tsitsekian D, Iacovides TA, Hatzopoulos P. Potassium transporter TRH1 subunits assemble regulating root-hair elongation autonomously from the cell fate determination pathway. Plant Sci 2015; 231:131-7. [PMID: 25575998 DOI: 10.1016/j.plantsci.2014.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 11/24/2014] [Accepted: 11/28/2014] [Indexed: 05/17/2023]
Abstract
Trichoblasts of trh1 plants form root-hair initiation sites that fail to undergo tip growth resulting in a tiny root-hair phenotype. TRH1 belongs to Arabidopsis KT/KUP/HAK potassium transporter family controlling root-hair growth and gravitropism. Double mutant combinations between trh1 and root-hair mutants affecting cell fate or root-hair initiation exhibited additive phenotypes, suggesting that TRH1 acts independently and developmentally downstream of root-hair initiation. Bimolecular Fluorescence Complementation (BiFC), upon TRH1-YFP(C) and TRH1-YFP(N) co-transformation into tobacco epidermal cells, led to fluorescence emission indicative of TRH1 subunit homodimerization. Yeast two-hybrid analysis revealed two types of interactions. The hydrophilic segment between the second and the third transmembrane domain extending from residues Q105 to T141 is competent for a relatively weak interaction, whereas the region at the C-terminal beyond the last transmembrane domain, extending from amino acids R565 to A729, strongly self-interacts. These domains likely facilitate the co-assembly of TRH1 subunits forming an active K(+) transport system within cellular membrane structures. The results support the role of TRH1 acting as a convergence point between the developmental root-hair pathway and the environmental/hormonal signaling pathway to preserve auxin homeostasis ensuring plant adaptation in changing environments.
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Affiliation(s)
- Gerasimos Daras
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75,118 55, Athens, Greece.
| | - Stamatis Rigas
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75,118 55, Athens, Greece.
| | - Dikran Tsitsekian
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75,118 55, Athens, Greece.
| | - Tefkros A Iacovides
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75,118 55, Athens, Greece.
| | - Polydefkis Hatzopoulos
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75,118 55, Athens, Greece.
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28
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Rubio F, Fon M, Ródenas R, Nieves-Cordones M, Alemán F, Rivero RM, Martínez V. A low K+ signal is required for functional high-affinity K+ uptake through HAK5 transporters. Physiol Plant 2014; 152:558-70. [PMID: 24716623 DOI: 10.1111/ppl.12205] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 02/17/2014] [Accepted: 03/06/2014] [Indexed: 05/27/2023]
Abstract
The high-affinity K(+) transporter HAK5 is a key system for root K(+) uptake and, under very low external K(+), the only one capable of supplying K(+) to the plant. Functional HAK5-mediated K(+) uptake should be tightly regulated for plant adaptation to different environmental conditions. Thus, it has been described that the gene encoding the transporter is transcriptionally regulated, being highly induced under K(+) limitation. Here we show that environmental conditions, such as the lack of K(+), NO(3)(-) or P, that induced a hyperpolarization of the plasma membrane of root cells, induce HAK5 transcription. However, only the deprivation of K(+) produces functional HAK5-mediated K(+) uptake in the root. These results suggest on the one hand the existence of a posttranscriptional regulation of HAK5 elicited by the low K(+) signal and on the other that HAK5 may be involved in yet-unknown functions related to NO(3)(-) and P deficiencies. These results have been obtained here with Solanum lycopersicum (cv. Micro-Tom) as well as Arabidopsis thaliana plants, suggesting that the posttranscriptional regulation of high-affinity HAK transporters take place in all plant species.
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Affiliation(s)
- Francisco Rubio
- Departamento de Nutrición Vegetal, CEBAS-CSIC, Campus de Espinardo, Murcia, 30100, Spain
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29
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Zheng S, Pan T, Fan L, Qiu QS. A novel AtKEA gene family, homolog of bacterial K+/H+ antiporters, plays potential roles in K+ homeostasis and osmotic adjustment in Arabidopsis. PLoS One 2013; 8:e81463. [PMID: 24278440 PMCID: PMC3835744 DOI: 10.1371/journal.pone.0081463] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 10/13/2013] [Indexed: 12/28/2022] Open
Abstract
AtKEAs, homologs of bacterial KefB/KefC, are predicted to encode K+/H+ antiporters in Arabidopsis. The AtKEA family contains six genes forming two subgroups in the cladogram: AtKEA1-3 and AtKEA4-6. AtKEA1 and AtKEA2 have a long N-terminal domain; the full-length AtKEA1 was inactive in yeast. The transport activity was analyzed by expressing the AtKEA genes in yeast mutants lacking multiple ion carriers. AtKEAs conferred resistance to high K+ and hygromycin B but not to salt and Li+ stress. AtKEAs expressed in both the shoot and root of Arabidopsis. The expression of AtKEA1, -3 and -4 was enhanced under low K+ stress, whereas AtKEA2 and AtKEA5 were induced by sorbitol and ABA treatments. However, osmotic induction of AtKEA2 and AtKEA5 was not observed in aba2-3 mutants, suggesting an ABA regulated mechanism for their osmotic response. AtKEAs’ expression may not be regulated by the SOS pathway since their expression was not affected in sos mutants. The GFP tagging analysis showed that AtKEAs distributed diversely in yeast. The Golgi localization of AtKEA3 was demonstrated by both the stably transformed seedlings and the transient expression in protoplasts. Overall, AtKEAs expressed and localized diversely, and may play roles in K+ homeostasis and osmotic adjustment in Arabidopsis.
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Affiliation(s)
- Sheng Zheng
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Ting Pan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Ligang Fan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
- *
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30
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Xu Y, Zhou Y, Hong S, Xia Z, Cui D, Guo J, Xu H, Jiang X. Functional characterization of a wheat NHX antiporter gene TaNHX2 that encodes a K(+)/H(+) exchanger. PLoS One 2013; 8:e78098. [PMID: 24223765 PMCID: PMC3815223 DOI: 10.1371/journal.pone.0078098] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 09/09/2013] [Indexed: 12/22/2022] Open
Abstract
The subcellular localization of a wheat NHX antiporter, TaNHX2, was studied in Arabidopsis protoplasts, and its function was evaluated using Saccharomyces cerevisiae as a heterologous expression system. Fluorescence patterns of TaNHX2-GFP fusion protein in Arabidopsis cells indicated that TaNHX2 localized at endomembranes. TaNHX2 has significant sequence homology to NHX sodium exchangers from Arabidopsis, is abundant in roots and leaves and is induced by salt or dehydration treatments. Western blot analysis showed that TaNHX2 could be expressed in transgenic yeast cells. Expressed TaNHX2 protein suppressed the salt sensitivity of a yeast mutant strain by increasing its K+ content when exposed to salt stress. TaNHX2 also increased the tolerance of the strain to potassium stress. However, the expression of TaNHX2 did not affect the sodium concentration in transgenic cells. Western blot analysis for tonoplast proteins indicated that the TaNHX2 protein localized at the tonoplast of transgenic yeast cells. The tonoplast vesicles from transgenic yeast cells displayed enhanced K+/H+ exchange activity but very little Na+/H+ exchange compared with controls transformed with the empty vector; Na+/H+ exchange was not detected with concentrations of less than 37.5 mM Na+ in the reaction medium. Our data suggest that TaNHX2 is a endomembrane-bound protein and may primarily function as a K+/H+ antiporter, which is involved in cellular pH regulation and potassium nutrition under normal conditions. Under saline conditions, the protein mediates resistance to salt stress through the intracellular compartmentalization of potassium to regulate cellular pH and K+ homeostasis.
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Affiliation(s)
- Yuanyuan Xu
- College of Agronomy/Key laboratory of Physiological Ecology and Genetic Improvement of Food Crops in Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Yang Zhou
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources/College of Agriculture, Hainan University, Haikou, China
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Sha Hong
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources/College of Agriculture, Hainan University, Haikou, China
| | - Zhihui Xia
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources/College of Agriculture, Hainan University, Haikou, China
| | - Dangqun Cui
- College of Agronomy/Key laboratory of Physiological Ecology and Genetic Improvement of Food Crops in Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Jianchun Guo
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Haixia Xu
- College of Agronomy/Key laboratory of Physiological Ecology and Genetic Improvement of Food Crops in Henan Province, Henan Agricultural University, Zhengzhou, China
- * E-mail: (HX); (XJ)
| | - Xingyu Jiang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources/College of Agriculture, Hainan University, Haikou, China
- * E-mail: (HX); (XJ)
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31
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Haro R, Fraile-Escanciano A, González-Melendi P, Rodríguez-Navarro A. The potassium transporters HAK2 and HAK3 localize to endomembranes in Physcomitrella patens. HAK2 is required in some stress conditions. Plant Cell Physiol 2013; 54:1441-1454. [PMID: 23825217 DOI: 10.1093/pcp/pct097] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The function of HAK transporters in high-affinity K+ uptake in plants is well established; this study aims to demonstrate that some transporters of the same family play important roles in endomembranes. The PpHAK2-PpHAK4 genes of Physcomitrella patens encode three transporters of high sequence similarity. Quantitative PCR showed that PpHAK2 and PpHAK3 transcripts are expressed at approximately the same level as the PpACT5 gene, while the expression of PpHAK4 seems to be restricted to specific conditions that have not been determined. KHA1 is an endomembrane K+/H+ antiporter of Saccharomyces cerevisiae, and the expression of the PpHAK2 cDNA, but not that of PpHAK3, suppressed the defect of a kha1 mutant. Transient expression of the PpHAK2-green fluorescent protein (GFP) and PpHAK3-GFP fusion proteins in P. patens protoplasts localized to the endoplasmic reticulum and Golgi complex, respectively. To determine the function of PpHAK2 and PpHAK3 in planta, we constructed ΔPphak2 and ΔPphak2 ΔPphak3 plants. ΔPphak2 plants were normal under all of the conditions tested except under K+ starvation or at acidic pH in the presence of acetic acid, whereupon they die. The defect observed under K+ starvation was suppressed by the presence of Na+. We propose that PpHAK2 may encode either a K(+)-H(+) symporter or a K+/H+ antiporter that mediates the transfer of H+ from the endoplasmic reticulum lumen to the cytosol. PpHAK2 may be a model of the second function of HAK transporters in plant cells. The disruption of the PpHAK3 gene in ΔPphak2 plants showed no effect.
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Affiliation(s)
- Rosario Haro
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus de Montegancedo, Carretera M-40, km 38, 28223 Pozuelo de Alarcón, Madrid, Spain.
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32
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Jiang C, Belfield EJ, Cao Y, Smith JAC, Harberd NP. An Arabidopsis soil-salinity-tolerance mutation confers ethylene-mediated enhancement of sodium/potassium homeostasis. Plant Cell 2013; 25:3535-52. [PMID: 24064768 PMCID: PMC3809548 DOI: 10.1105/tpc.113.115659] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/28/2013] [Accepted: 09/03/2013] [Indexed: 05/18/2023]
Abstract
High soil Na concentrations damage plants by increasing cellular Na accumulation and K loss. Excess soil Na stimulates ethylene-induced soil-salinity tolerance, the mechanism of which we here define via characterization of an Arabidopsis thaliana mutant displaying transpiration-dependent soil-salinity tolerance. This phenotype is conferred by a loss-of-function allele of ethylene overproducer1 (ETO1; mutant alleles of which cause increased production of ethylene). We show that lack of ETO1 function confers soil-salinity tolerance through improved shoot Na/K homeostasis, effected via the ethylene resistant1-constitutive triple response1 ethylene signaling pathway. Under transpiring conditions, lack of ETO1 function reduces root Na influx and both stelar and xylem sap Na concentrations, thereby restricting root-to-shoot delivery of Na. These effects are associated with increased accumulation of respiratory burst oxidase homolog F (RBOHF)-dependent reactive oxygen species in the root stele. Additionally, lack of ETO1 function leads to significant enhancement of tissue K status by an RBOHF-independent mechanism associated with elevated high-affinity K(+) TRANSPORTER5 transcript levels. We conclude that ethylene promotes soil-salinity tolerance via improved Na/K homeostasis mediated by RBOHF-dependent regulation of Na accumulation and RBOHF-independent regulation of K accumulation.
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Affiliation(s)
- Caifu Jiang
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Eric J. Belfield
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Yi Cao
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - J. Andrew C. Smith
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Nicholas P. Harberd
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
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Kieseritzky G, Knapp EW. Charge transport in the ClC-type chloride-proton anti-porter from Escherichia coli. J Biol Chem 2011; 286:2976-86. [PMID: 21059656 PMCID: PMC3024792 DOI: 10.1074/jbc.m110.163246] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 11/04/2010] [Indexed: 11/06/2022] Open
Abstract
The first chloride transporter identified in the superfamily of ClC chloride channels was from Escherichia coli (EClC) (Accardi, A., and Miller, C. (2004) Nature 427, 803-807). Pathways, energetics, and mechanism of proton and chloride translocation and their coupling are up to now unclear. To bridge the hydrophobic gap of proton transport, we modeled four stable buried waters into both subunits of the WT EClC structure. Together they form a "water wire" connecting Glu-203 with the chloride at the central site, which in turn connects to Glu-148, the hypothetical proton exit site. Assuming the transient production of hydrochloride in the central chloride binding site of EClC, the water wire could establish a transmembrane proton transport pathway starting from Glu-203 all the way downstream onto Glu-148. We demonstrated by electrostatic and quantum chemical computations that protonation of the central chloride is energetically feasible. We characterized all chloride occupancies and protonation states possibly relevant for the proton-chloride transport cycle in EClC and constructed a working model. Accordingly, EClC evolves through states involving up to two excess protons and between one and three chlorides, which was required to fulfill the experimentally observed 2:1 stoichiometry. We show that the Y445F and E203H mutants of EClC can operate similarly, thus explaining why they exhibit almost WT activity levels. The proposed mechanism of coupled chloride-proton transport in EClC is consistent with available experimental data and allows predictions on the importance of specific amino acids, which may be probed by mutation experiments.
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Affiliation(s)
- Gernot Kieseritzky
- From the Freie Universität Berlin, Institut für Chemie, Fabeckstrasse 36a, D-14195 Berlin, Germany
| | - Ernst-Walter Knapp
- From the Freie Universität Berlin, Institut für Chemie, Fabeckstrasse 36a, D-14195 Berlin, Germany
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Liu H, Tang R, Zhang Y, Wang C, Lv Q, Gao X, Li W, Zhang H. AtNHX3 is a vacuolar K+/H+ antiporter required for low-potassium tolerance in Arabidopsis thaliana. Plant Cell Environ 2010; 33:1989-99. [PMID: 20573049 DOI: 10.1111/j.1365-3040.2010.02200.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Three vacuolar cation/H+ antiporters, AtNHX1 (At5g27150), 2 (At3g05030) and 5 (At1g54370), have been characterized as functional Na+/H+ antiporters in Arabidopsis. However, the physiological functions of AtNHX3 (At5g55470) still remain unclear. In this study, the physiological functions of AtNHX3 were studied using T-DNA insertion mutant and 35S-driven AtNHX3 over-expression Arabidopsis plants. RT-PCR analyses revealed that AtNHX3 is highly expressed in germinating seeds, flowers and siliques. Experiments with AtNHX3::YFP fusion protein in tobacco protoplasts indicated that AtNHX3 is mainly localized to vacuolar membrane, with a minor localization to pre-vacuolar compartments (PVCs) and endoplasmic reticulum (ER). Seedlings of null nhx3 mutants were hypersensitive to K+-deficient conditions. Expression of AtNHX3 complemented the sensitivity to K+ deficiency in nhx3 seedlings. Tonoplast vesicles isolated from transgenic plants over-expressing AtNHX3 displayed significantly higher K+/H+ exchange rates than those isolated from wild-type plants. Furthermore, nhx3 seeds accumulated less K+ and more Na+ when both wild-type and nhx3 were grown under normal growth condition. The overall results indicate that AtNHX3 encodes a K+/H+ antiporter required for low-potassium tolerance during germination and early seedling development, and may function in K+ utilization and ion homeostasis in Arabidopsis.
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Affiliation(s)
- Hua Liu
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
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Rodríguez-Rosales MP, Gálvez FJ, Huertas R, Aranda MN, Baghour M, Cagnac O, Venema K. Plant NHX cation/proton antiporters. Plant Signal Behav 2009; 4:265-76. [PMID: 19794841 PMCID: PMC2664485 DOI: 10.4161/psb.4.4.7919] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Accepted: 01/23/2009] [Indexed: 05/18/2023]
Abstract
Although physiological and biochemical data since long suggested that Na(+)/H(+) and K(+)/H(+) antiporters are involved in intracellular ion and pH regulation in plants, it has taken a long time to identify genes encoding antiporters that could fulfil these roles. Genome sequencing projects have now shown that plants contain a very large number of putative Cation/Proton antiporters, the function of which is only beginning to be studied. The intracellular NHX transporters constitute the first Cation/Proton exchanger family studied in plants. The founding member, AtNHX1, was identified as an important salt tolerance determinant and suggested to catalyze Na(+) accumulation in vacuoles. It is, however, becoming increasingly clear, that this gene and other members of the family also play crucial roles in pH regulation and K(+) homeostasis, regulating processes from vesicle trafficking and cell expansion to plant development.
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36
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Rodríguez-Rosales MP, Jiang X, Gálvez FJ, Aranda MN, Cubero B, Venema K. Overexpression of the tomato K+/H+ antiporter LeNHX2 confers salt tolerance by improving potassium compartmentalization. New Phytol 2008; 179:366-377. [PMID: 19086176 DOI: 10.1111/j.1469-8137.2008.02461.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Here, the function of the tomato (Solanum lycopersicon) K+/H+ antiporter LeNHX2 was studied using 35S-driven gene overexpression of a histagged LeNHX2 protein in Arabidopsis thaliana and LeNHX2 gene silencing in tomato. Transgenic A. thaliana plants expressed the histagged LeNHX2 both in shoots and in roots, as assayed by western blotting. Transitory expression of a green fluorescent protein (GFP) tagged protein showed that the antiporter is present in small vesicles. Internal membrane vesicles from transgenic plants displayed enhanced K+/H+ exchange activity, confirming the K+/H+ antiporter function of this enzyme. Transgenic A. thaliana plants overexpressing the histagged tomato antiporter LeNHX2 exhibited inhibited growth in the absence of K+ in the growth medium, but were more tolerant to high concentrations of Na+ than untransformed controls. When grown in the presence of NaCl, transgenic plants contained lower concentrations of intracellular Na+, but more K+, as compared with untransformed controls. Silencing of LeNHX2 in S. lycopersicon plants produced significant inhibition of plant growth and fruit and seed production as well as increased sensitivity to NaCl. The data indicate that regulation of K+ homeostasis by LeNHX2 is essential for normal plant growth and development, and plays an important role in the response to salt stress by improving K+ accumulation.
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Affiliation(s)
- María Pilar Rodríguez-Rosales
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Xingyu Jiang
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
- Department of Plant Biology, Instituto de Recursos Naturales y Agrobiología, CSIC, 41012 Sevilla, Spain
| | - Francisco Javier Gálvez
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - María Nieves Aranda
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Beatriz Cubero
- Department of Plant Biology, Instituto de Recursos Naturales y Agrobiología, CSIC, 41012 Sevilla, Spain
| | - Kees Venema
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
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37
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Abstract
AtChx17p is a putative K(+)/H(+) exchanger from Arabidopsis thaliana, expressed in the roots and probably involved in K(+) acquisition and homeostasis. AtCHX17 cDNA complements the phenotypes of the kha1Delta mutation in S. cerevisiae cells: a growth defect at increased pH and hygromycin sensitivity. The localization of GFP-tagged AtChx17 protein in yeast cells is similar to that of ScKha1p: a bold dotted pattern inside the cells resembling the Golgi fluorescence markers. These results show that (a) the proteins AtChx17 and ScKha1 could have similar functions and (b) S. cerevisiae kha1 deletion mutants could serve for the heterologous expression and characterization of plant transporters. The results of this work are evidence that a S. cerevisiae strain with deletions of genes encoding alkali-metal-cation/H(+) antiporters (i.e. Nha1p, Nhx1p, Kha1p) could be an ideal tool for expression and functional analysis of any type of similar plant antiporters (plasma membrane, endosomal/prevacuolar and Golgi).
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Affiliation(s)
- Lydie Maresova
- Department of Membrane Transport, Institute of Physiology, Academy of Sciences, CR, Videnska 1083, 142 20 Prague 4, Czech Republic.
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Pribylová L, Papousková K, Zavrel M, Souciet JL, Sychrová H. Exploration of yeast alkali metal cation/H+ antiporters: Sequence and structure comparison. Folia Microbiol (Praha) 2006; 51:413-24. [PMID: 17176761 DOI: 10.1007/bf02931585] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The Saccharomyces cerevisiae genome contains three genes encoding alkali metal cation/H+ antiporters (Nha1p, Nhx1p, Kha1p) that differ in cell localization, substrate specificity and physiological function. Systematic genome sequencing of other yeast species revealed highly conserved homologous ORFs in all of them. We compared the yeast sequences both at DNA and protein levels. The subfamily of yeast endosomal/prevacuolar Nhx1 antiporters is closely related to mammalian plasma membrane NHE proteins and to both plasma membrane and vacuolar plant antiporters. The high sequence conservation within this subfamily of yeast antiporters suggests that Nhx1p is of great importance in cell physiology. Yeast Kha1 proteins probably belong to the same subfamily as bacterial antiporters, whereas Nhal proteins form a distinct subfamily.
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Affiliation(s)
- L Pribylová
- Department of Membrane Transport, Institute of Physiology, Academy of Sciences of the Czech Republic, 142 20 Prague, Czechia
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Radchenko MV, Waditee R, Oshimi S, Fukuhara M, Takabe T, Nakamura T. Cloning, functional expression and primary characterization of Vibrio parahaemolyticus K+/H+ antiporter genes in Escherichia coli. Mol Microbiol 2006; 59:651-63. [PMID: 16390457 DOI: 10.1111/j.1365-2958.2005.04966.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The regulation of internal Na(+) and K(+) concentrations is important for bacterial cells, which, in the absence of Na(+) extrusion systems, cannot grow in the presence of high external Na(+). Likewise, bacteria require K(+) uptake systems when the external K(+) concentration becomes too low to support growth. At present, we have little knowledge of K(+) toxicity and bacterial outward-directed K(+) transport systems. We report here that high external concentrations of K(+) at alkaline pH are toxic and that bacteria require K(+) efflux and/or extrusion systems to avoid excessive K(+) accumulation. We have identified the first example of a bacterial K(+)(specific)/H(+) antiporter, Vp-NhaP2, from Vibrio parahaemolyticus. This protein, a member of the cation : proton antiporter-1 (CPA1) family, was able to mediate K(+) extrusion from the cell to provide tolerance to high concentrations of external KCl at alkaline pH. We also report the discovery of two V. parahaemolyticus Na(+)/H(+) antiporters, Vp-NhaA and Vp-NhaB, which also exhibit a novel ion specificity toward K(+), implying that they work as Na(+)(K(+))/H(+) exchangers. Furthermore, under specific conditions, Escherichia coli was able to mediate K(+) extrusion against a K(+) chemical gradient, indicating that E. coli also possesses an unidentified K(+) extrusion system(s).
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Affiliation(s)
- Martha V Radchenko
- Department of Microbiology, Niigata University of Pharmacy and Applied Life Sciences, Niigata 950-2081, Japan
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40
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Radchenko MV, Tanaka K, Waditee R, Oshimi S, Matsuzaki Y, Fukuhara M, Kobayashi H, Takabe T, Nakamura T. Potassium/proton antiport system of Escherichia coli. J Biol Chem 2006; 281:19822-9. [PMID: 16687400 DOI: 10.1074/jbc.m600333200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The intracellular level of potassium (K(+)) in Escherichia coli is regulated through multiple K(+) transport systems. Recent data indicate that not all K(+) extrusion system(s) have been identified (15). Here we report that the E. coli Na(+) (Ca(2+))/H(+) antiporter ChaA functions as a K(+) extrusion system. Cells expressing ChaA mediated K(+) efflux against a K(+) concentration gradient. E. coli strains lacking the chaA gene were unable to extrude K(+) under conditions in which wild-type cells extruded K(+). The K(+)/H(+) antiporter activity of ChaA was detected by using inverted membrane vesicles produced using a French press. Physiological growth studies indicated that E. coli uses ChaA to discard excessive K(+), which is toxic for these cells. These results suggest that ChaA K(+)/H(+) antiporter activity enables E. coli to adapt to K(+) salinity stress and to maintain K(+) homeostasis.
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Affiliation(s)
- Martha V Radchenko
- Department of Microbiology, Niigata University of Pharmacy and Applied Life Sciences, Niigata 950-2081, Japan
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41
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Flis K, Hinzpeter A, Edelman A, Kurlandzka A. The functioning of mammalian ClC-2 chloride channel in Saccharomyces cerevisiae cells requires an increased level of Kha1p. Biochem J 2006; 390:655-64. [PMID: 15926887 PMCID: PMC1199658 DOI: 10.1042/bj20050480] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The mammalian chloride channel ClC-2 is a member of the CLC voltage-gated chloride channels family. This broadly expressed protein shows diverse cellular locations and despite numerous studies, its precise function is poorly understood. Disruption of ClC-2-encoding gene in mouse leads to retinal and testicular degeneration and mutations in CLC2 (gene encoding the ClC-2 channel) are associated with idiopathic generalized epilepsies. ClC-2 may also be responsible for Cl- transport in mouse salivary glands. The only CLC homologue of the yeast Saccharomyces cerevisiae, Gef1p, exhibits CLC activity. We expressed the mammalian ClC-2 protein in S. cerevisiae devoid of Gef1p in an attempt to identify yeast proteins influencing the functioning of ClC-2. The presence of such proteins in yeast could indicate the existence of their homologues in mammalian cells and would greatly aid their identification. Expression of ClC-2 in yeast required optimization of the sequence context of the AUG translation initiation codon. After obtaining an efficient translation, we found that rat ClC-2 cannot directly substitute for yeast Gef1p. Functional substitution for Gef1p was, however, achieved in the presence of an increased level of intact or C-terminally truncated yeast Kha1 protein. Based on the deduced amino acid sequence, the Kha1 protein can be classified as a Na+/H+ transporter since it has a large N-terminal domain similar to the family of NHEs (Na+/H+ exchangers). This suggests that the Kha1p may take part in the regulation of intracellular cation homoeostasis and pH control. We have established that Kha1p is localized in the same cellular compartment as Gef1p and yeast-expressed ClC-2: the Golgi apparatus. We propose that Kha1p may aid ClC-2-dependent suppression of the Deltagef1-associated growth defects by keeping the Golgi apparatus pH in a range suitable for ClC-2 activity. The approach employed in the present study may be of general applicability to the characterization of poorly understood proteins by their functional expression in yeast.
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Affiliation(s)
- Krzysztof Flis
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland.
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42
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Froschauer E, Nowikovsky K, Schweyen RJ. Electroneutral K+/H+ exchange in mitochondrial membrane vesicles involves Yol027/Letm1 proteins. Biochimica et Biophysica Acta (BBA) - Biomembranes 2005; 1711:41-8. [PMID: 15904662 DOI: 10.1016/j.bbamem.2005.02.018] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2004] [Revised: 02/08/2005] [Accepted: 02/28/2005] [Indexed: 10/25/2022]
Abstract
YOL027c in yeast and LETM1 in humans encode integral proteins of the inner mitochondrial membrane. They have been implicated in mitochondrial K+ homeostasis and volume control. To further characterize their role, we made use of submitochondrial particles (SMPs) with entrapped K+- and H+-sensitive fluorescent dyes PBFI and BCECF, respectively, to study the kinetics of K+ and H+ transport across the yeast inner mitochondrial membrane. Wild-type SMPs exhibited rapid, reciprocal translocations of K+ and H+ driven by concentration gradients of either of them. K+ and H+ translocations have stoichiometries similar to those mediated by the exogenous K+/H+ exchanger nigericin, and they are shown to be essentially electroneutral and obligatorily coupled. Moreover, [K+] gradients move H+ against its concentration gradient, and vice-versa. These features, as well as the sensitivity of K+ and H+ fluxes to quinine and Mg2+, qualify these activities as K+/H+ exchange reactions. Both activities are abolished when the yeast Yol027p protein is absent (yol027Delta mutant SMPs), indicating that it has an essential role in this reaction. The replacement of the yeast Yol027p by the human Letm1 protein restores K+/H+ exchange activity confirming functional homology of the yeast and human proteins. Considering their newly identified function, we propose to refer to the yeast YOL027c gene and the human LETM1 gene as yMKH1 and hMKH1, respectively.
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Affiliation(s)
- Elisabeth Froschauer
- Max F. Perutz Laboratories, Department of Microbiology and Genetics, University of Vienna, Campus Vienna Biocenter, Dr. Bohrgasse 9, A-1030 Vienna, Austria
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43
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Abstract
Maintenance of intracellular K+ homeostasis is one of the crucial requisites for the survival of yeast cells. In Saccharomyces cerevisiae, the high K+ content corresponds to a steady state between simultaneous influx and efflux across the plasma membrane. One of the transporters formerly believed to extrude K+ from the yeast cells (besides Ena1-4p and Nha1p) was named Kha1p and presumed as a putative plasma membrane K+/H+ antiporter. We prepared kha1 and tok1-kha1 deletion strains in the B31 and MAB 2d background. Both the strains contain the ena1-4 and nha1 deletions; that means they lack the main active sodium and potassium efflux systems. MAB 2d has additional trk1 and trk2 deletions, i.e. is impaired in active K+ uptake as well. We performed a large physiological study with these strains to specify the phenotype of kha1 deletion. In our experiments, no difference in K+ content or efflux was observed in strains lacking the KHA1 gene compared with control strains. Two main phenotype manifestations of the kha1 deletion were growth defect on high external pH and hygromycin sensitivity. The correlation between these phenotypes and the kha1 deletion was confirmed by plasmid complementation. Fluorescence microscopy of green fluorescent protein (GFP)-tagged Kha1p showed that this antiporter is localized preferentially intracellularly (in contrast to the plasma membrane Na+/H+ antiporter Nha1p). Based on these findings, Kha1p is probably not localized in plasma membrane and does not mediate efflux of alkali metal cations from cells, but is important for the regulation of intracellular cation homeostasis and optimal pH control, similarly as the Nhx1p.
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Affiliation(s)
- Lydie Maresova
- Department of Membrane Transport, Institute of Physiology, Academy of Sciences CR, 142 20 Prague 4, Czech Republic.
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44
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Venema K, Belver A, Marin-Manzano MC, Rodríguez-Rosales MP, Donaire JP. A novel intracellular K+/H+ antiporter related to Na+/H+ antiporters is important for K+ ion homeostasis in plants. J Biol Chem 2003; 278:22453-9. [PMID: 12695519 DOI: 10.1074/jbc.m210794200] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study we have identified the first plant K+/H+ exchanger, LeNHX2 from tomato (Lycopersicon esculentum Mill. cv. Moneymaker), which is a member of the intracellular NHX exchanger protein family. The LeNHX2 protein, belonging to a subfamily of plant NHX proteins closely related to the yeast NHX1 protein, is abundant in roots and stems and is induced in leaves by short term salt or abscisic acid treatment. LeNHX2 complements the salt- and hygromycin-sensitive phenotype caused by NHX1 gene disruption in yeast, but affects accumulation of K+ and not Na+ in intracellular compartments. The LeNHX2 protein co-localizes with Prevacuolar and Golgi markers in a linear sucrose gradient in both yeast and plants. A histidine-tagged version of this protein could be purified and was shown to catalyze K+/H+ exchange but only minor Na+/H+ exchange in vitro. These data indicate that proper functioning of the endomembrane system relies on the regulation of K+ and H+ homeostasis by K+/H+ exchangers.
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Affiliation(s)
- Kees Venema
- Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, CSIC, Apartado 419, 18080-Granada, Spain.
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Kang L, Zhu H, Cheng Q, Zhou W, Sun L, Cai L, Ma X, Chen C, Zhao S, Li C. Cloning and characterization of a gene encoding glutathione-regulated potassium-efflux system protein KefKL from the endosymbiont Wolbachia. DNA Seq 2002; 13:375-81. [PMID: 12652910 DOI: 10.1080/1042517021000003897] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The maternally inherited intracellular symbiont Wolbachia is well known for inducing a variety of reproductive and developmental abnormalities in the diverse arthropod hosts it infects. It has been implicated in causing cytoplasmic incompatibility (CI), parthenogenesis, feminization of genetic males and male killing in different hosts. However, the molecular mechanisms by which this fastidious bacterium causes these abnormalities have not yet been determined. In our study, representational difference analysis (RDA) was used to analyze the genomic difference between different Wolbachia strains. A gene encoding glutathione-regulated potassium-efflux system protein KefKL from Wolbachia in Drosophila simulans Riverside (w Ri) was isolated. The homologous genes from Wolbachia in Drosophila melanogaster yw67c23 (wMel) and Wolbachia in Drosophila melanogaster CantonS (wMelCS) were also cloned and sequenced. Sequence analysis showed that these deduced amino acid sequences contained two important motifs: Na+/H+ antiportor and NAD binding domain, which shared conserved sequences among different strains. Considering the crucial function of KefKL for ionic homeostasis, this gene might play an important role in Wolbachia physiology. Further study indicated that there was no homologue detected from Wolbachia in Drosophila simulans DSW/Mau (wMa) and Wolbachia in Drosophila simulans Noumea (wNo). Whether Wolbachia contained KefKL (or the homologous gene) was consistent with the phylogenetic studies using wsp sequences, which showed that wMa and wNo were grouped into one branch, while w Ri, wMel and wMelCS were more closely related.
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Affiliation(s)
- Lin Kang
- Institute of Genetics, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433, People's Republic of China
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