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Xue B, Duan W, Gong L, Zhu D, Li X, Li X, Liang YK. The OsDIR55 gene increases salt tolerance by altering the root diffusion barrier. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1550-1568. [PMID: 38412303 DOI: 10.1111/tpj.16696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 01/30/2024] [Accepted: 02/07/2024] [Indexed: 02/29/2024]
Abstract
The increased soil salinity is becoming a major challenge to produce more crops and feed the growing population of the world. In this study, we demonstrated that overexpression of OsDIR55 gene enhances rice salt tolerance by altering the root diffusion barrier. OsDIR55 is broadly expressed in all examined tissues and organs with the maximum expression levels at lignified regions in rice roots. Salt stress upregulates the expression of OsDIR55 gene in an abscisic acid (ABA)-dependent manner. Loss-function and overexpression of OsDIR55 compromised and improved the development of CS and root diffusion barrier, manifested with the decreased and increased width of CS, respectively, and ultimately affected the permeability of the apoplastic diffusion barrier in roots. OsDIR55 deficiency resulted in Na+ accumulation, ionic imbalance, and growth arrest, whereas overexpression of OsDIR55 enhances salinity tolerance and provides an overall benefit to plant growth and yield potential. Collectively, we propose that OsDIR55 is crucial for ions balance control and salt stress tolerance through regulating lignification-mediated root barrier modifications in rice.
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Affiliation(s)
- Baoping Xue
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Wen Duan
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Luping Gong
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Dongmei Zhu
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Xueying Li
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Xuemei Li
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Yun-Kuan Liang
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
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Lindberg S, Premkumar A. Ion Changes and Signaling under Salt Stress in Wheat and Other Important Crops. PLANTS (BASEL, SWITZERLAND) 2023; 13:46. [PMID: 38202354 PMCID: PMC10780558 DOI: 10.3390/plants13010046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/14/2023] [Accepted: 12/16/2023] [Indexed: 01/12/2024]
Abstract
High concentrations of sodium (Na+), chloride (Cl-), calcium (Ca2+), and sulphate (SO42-) are frequently found in saline soils. Crop plants cannot successfully develop and produce because salt stress impairs the uptake of Ca2+, potassium (K+), and water into plant cells. Different intracellular and extracellular ionic concentrations change with salinity, including those of Ca2+, K+, and protons. These cations serve as stress signaling molecules in addition to being essential for ionic homeostasis and nutrition. Maintaining an appropriate K+:Na+ ratio is one crucial plant mechanism for salt tolerance, which is a complicated trait. Another important mechanism is the ability for fast extrusion of Na+ from the cytosol. Ca2+ is established as a ubiquitous secondary messenger, which transmits various stress signals into metabolic alterations that cause adaptive responses. When plants are under stress, the cytosolic-free Ca2+ concentration can rise to 10 times or more from its resting level of 50-100 nanomolar. Reactive oxygen species (ROS) are linked to the Ca2+ alterations and are produced by stress. Depending on the type, frequency, and intensity of the stress, the cytosolic Ca2+ signals oscillate, are transient, or persist for a longer period and exhibit specific "signatures". Both the influx and efflux of Ca2+ affect the length and amplitude of the signal. According to several reports, under stress Ca2+ alterations can occur not only in the cytoplasm of the cell but also in the cell walls, nucleus, and other cell organelles and the Ca2+ waves propagate through the whole plant. Here, we will focus on how wheat and other important crops absorb Na+, K+, and Cl- when plants are under salt stress, as well as how Ca2+, K+, and pH cause intracellular signaling and homeostasis. Similar mechanisms in the model plant Arabidopsis will also be considered. Knowledge of these processes is important for understanding how plants react to salinity stress and for the development of tolerant crops.
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Affiliation(s)
- Sylvia Lindberg
- Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-114 18 Stockholm, Sweden
| | - Albert Premkumar
- Bharathiyar Group of Institutes, Guduvanchery 603202, Tamilnadu, India;
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Martins TS, Da-Silva CJ, Shabala S, Striker GG, Carvalho IR, de Oliveira ACB, do Amarante L. Understanding plant responses to saline waterlogging: insights from halophytes and implications for crop tolerance. PLANTA 2023; 259:24. [PMID: 38108902 DOI: 10.1007/s00425-023-04275-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 10/30/2023] [Indexed: 12/19/2023]
Abstract
MAIN CONCLUSION Saline and wet environments stress most plants, reducing growth and yield. Halophytes adapt with ion regulation, energy maintenance, and antioxidants. Understanding these mechanisms aids in breeding resilient crops for climate change. Waterlogging and salinity are two abiotic stresses that have a major negative impact on crop growth and yield. These conditions cause osmotic, ionic, and oxidative stress, as well as energy deprivation, thus impairing plant growth and development. Although few crop species can tolerate the combination of salinity and waterlogging, halophytes are plant species that exhibit high tolerance to these conditions due to their morphological, anatomical, and metabolic adaptations. In this review, we discuss the main mechanisms employed by plants exposed to saline waterlogging, intending to understand the mechanistic basis of their ion homeostasis. We summarize the knowledge of transporters and channels involved in ion accumulation and exclusion, and how they are modulated to prevent cytosolic toxicity. In addition, we discuss how reactive oxygen species production and cell signaling enhance ion transport and aerenchyma formation, and how plants exposed to saline waterlogging can control oxidative stress. We also address the morphological and anatomical modifications that plants undergo in response to combined stress, including aerenchyma formation, root porosity, and other traits that help to mitigate stress. Furthermore, we discuss the peculiarities of halophyte plants and their features that can be leveraged to improve crop yields in areas prone to saline waterlogging. This review provides valuable insights into the mechanisms of plant adaptation to saline waterlogging thus paving the path for future research on crop breeding and management strategies.
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Affiliation(s)
- Tamires S Martins
- Departamento de Botânica, Universidade Federal de Pelotas, Capão Do Leão, Brazil.
- Laboratory of Crop Physiology (LCroP), Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, Brazil.
| | - Cristiane J Da-Silva
- Departamento de Botânica, Universidade Federal de Pelotas, Capão Do Leão, Brazil.
- Department of Horticultural Science, NC State University, Raleigh, USA.
| | - Sergey Shabala
- School of Biological Science, University of Western Australia, Perth, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Australia
| | - Gustavo G Striker
- IFEVA, Universidad de Buenos Aires, CONICET, Facultad de Agronomía, Buenos Aires, Argentina
- School of Agriculture and Environment, Faculty of Science, The University of Western Australia, Crawley, Australia
| | - Ivan R Carvalho
- Departamento de Estudos Agrários, Universidade Regional do Noroeste do Estado do Rio Grande do Sul, Ijuí, Brazil
| | | | - Luciano do Amarante
- Departamento de Botânica, Universidade Federal de Pelotas, Capão Do Leão, Brazil
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Karumanchi AR, Sivan P, Kummari D, Rajasheker G, Kumar SA, Reddy PS, Suravajhala P, Podha S, Kishor PBK. Root and Leaf Anatomy, Ion Accumulation, and Transcriptome Pattern under Salt Stress Conditions in Contrasting Genotypes of Sorghum bicolor. PLANTS (BASEL, SWITZERLAND) 2023; 12:2400. [PMID: 37446963 DOI: 10.3390/plants12132400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/11/2023] [Accepted: 06/15/2023] [Indexed: 07/15/2023]
Abstract
Roots from salt-susceptible ICSR-56 (SS) sorghum plants display metaxylem elements with thin cell walls and large diameter. On the other hand, roots with thick, lignified cell walls in the hypodermis and endodermis were noticed in salt-tolerant CSV-15 (ST) sorghum plants. The secondary wall thickness and number of lignified cells in the hypodermis have increased with the treatment of sodium chloride stress to the plants (STN). Lignin distribution in the secondary cell wall of sclerenchymatous cells beneath the lower epidermis was higher in ST leaves compared to the SS genotype. Casparian thickenings with homogenous lignin distribution were observed in STN roots, but inhomogeneous distribution was evident in SS seedlings treated with sodium chloride (SSN). Higher accumulation of K+ and lower Na+ levels were noticed in ST compared to the SS genotype. To identify the differentially expressed genes among SS and ST genotypes, transcriptomic analysis was carried out. Both the genotypes were exposed to 200 mM sodium chloride stress for 24 h and used for analysis. We obtained 70 and 162 differentially expressed genes (DEGs) exclusive to SS and SSN and 112 and 26 DEGs exclusive to ST and STN, respectively. Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis unlocked the changes in metabolic pathways in response to salt stress. qRT-PCR was performed to validate 20 DEGs in each SSN and STN sample, which confirms the transcriptomic results. These results surmise that anatomical changes and higher K+/Na+ ratios are essential for mitigating salt stress in sorghum apart from the genes that are differentially up- and downregulated in contrasting genotypes.
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Affiliation(s)
- Appa Rao Karumanchi
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522 209, India
| | - Pramod Sivan
- Department of Chemistry, Division of Glycoscience, KTH Royal Institute of Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, Albanova University Center, SE-10691 Stockholm, Sweden
| | - Divya Kummari
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Hyderabad 502 324, India
| | - G Rajasheker
- Department of Genetics, Osmania University, Hyderabad 500 007, India
| | - S Anil Kumar
- Department of Biotechnology, Vignan's Foundation for Science, Technology & Research (Deemed to Be University), Guntur 522 213, India
| | - Palakolanu Sudhakar Reddy
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Hyderabad 502 324, India
| | | | - Sudhakar Podha
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522 209, India
| | - P B Kavi Kishor
- Department of Genetics, Osmania University, Hyderabad 500 007, India
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Shahzad B, Shabala L, Zhou M, Venkataraman G, Solis CA, Page D, Chen ZH, Shabala S. Comparing Essentiality of SOS1-Mediated Na + Exclusion in Salinity Tolerance between Cultivated and Wild Rice Species. Int J Mol Sci 2022; 23:9900. [PMID: 36077294 PMCID: PMC9456175 DOI: 10.3390/ijms23179900] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 01/22/2023] Open
Abstract
Soil salinity is a major constraint that affects plant growth and development. Rice is a staple food for more than half of the human population but is extremely sensitive to salinity. Among the several known mechanisms, the ability of the plant to exclude cytosolic Na+ is strongly correlated with salinity stress tolerance in different plant species. This exclusion is mediated by the plasma membrane (PM) Na+/H+ antiporter encoded by Salt Overly Sensitive (SOS1) gene and driven by a PM H+-ATPase generated proton gradient. However, it is not clear to what extent this mechanism is operational in wild and cultivated rice species, given the unique rice root anatomy and the existence of the bypass flow for Na+. As wild rice species provide a rich source of genetic diversity for possible introgression of abiotic stress tolerance, we investigated physiological and molecular basis of salinity stress tolerance in Oryza species by using two contrasting pairs of cultivated (Oryza sativa) and wild rice species (Oryza alta and Oryza punctata). Accordingly, dose- and age-dependent Na+ and H+ fluxes were measured using a non-invasive ion selective vibrating microelectrode (the MIFE technique) to measure potential activity of SOS1-encoded Na+/H+ antiporter genes. Consistent with GUS staining data reported in the literature, rice accessions had (~4-6-fold) greater net Na+ efflux in the root elongation zone (EZ) compared to the mature root zone (MZ). Pharmacological experiments showed that Na+ efflux in root EZ is suppressed by more than 90% by amiloride, indicating the possible involvement of Na+/H+ exchanger activity in root EZ. Within each group (cultivated vs. wild) the magnitude of amiloride-sensitive Na+ efflux was higher in tolerant genotypes; however, the activity of Na+/H+ exchanger was 2-3-fold higher in the cultivated rice compared with their wild counterparts. Gene expression levels of SOS1, SOS2 and SOS3 were upregulated under 24 h salinity treatment in all the tested genotypes, with the highest level of SOS1 transcript detected in salt-tolerant wild rice genotype O. alta (~5-6-fold increased transcript level) followed by another wild rice, O. punctata. There was no significant difference in SOS1 expression observed for cultivated rice (IR1-tolerant and IR29-sensitive) under both 0 and 24 h salinity exposure. Our findings suggest that salt-tolerant cultivated rice relies on the cytosolic Na+ exclusion mechanism to deal with salt stress to a greater extent than wild rice, but its operation seems to be regulated at a post-translational rather than transcriptional level.
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Affiliation(s)
- Babar Shahzad
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Lana Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University; Foshan 528000, China
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Gayatri Venkataraman
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai 600113, India
| | - Celymar Angela Solis
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
- School of Science, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| | - David Page
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Zhong-Hua Chen
- School of Science, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University; Foshan 528000, China
- School of Biological Science, University of Western Australia, Perth, WA 6009, Australia
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6
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Shahzad B, Yun P, Shabala L, Zhou M, Sellamuthu G, Venkataraman G, Chen ZH, Shabala S. Unravelling the physiological basis of salinity stress tolerance in cultivated and wild rice species. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:351-364. [PMID: 35189073 DOI: 10.1071/fp21336] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Wild rice species provide a rich source of genetic diversity for possible introgression of salinity stress tolerance in cultivated rice. We investigated the physiological basis of salinity stress tolerance in Oryza species by using six rice genotypes (Oryza sativa L.) and four wild rice species. Three weeks of salinity treatment significantly (P <0.05) reduced physiological and growth indices of all cultivated and wild rice lines. However, the impact of salinity-induced growth reduction differed substantially among accessions. Salt tolerant accessions showed better control over gas exchange properties, exhibited higher tissue tolerance, and retained higher potassium ion content despite higher sodium ion accumulation in leaves. Wild rice species showed relatively lower and steadier xylem sap sodium ion content over the period of 3weeks analysed, suggesting better control over ionic sodium xylem loading and its delivery to shoots with efficient vacuolar sodium ion sequestration. Contrary to this, saline sensitive genotypes managed to avoid initial Na+ loading but failed to accomplish this in the long term and showed higher sap sodium ion content. Conclusively, our results suggest that wild rice genotypes have more efficient control over xylem sodium ion loading, rely on tissue tolerance mechanisms and allow for a rapid osmotic adjustment by using sodium ions as cheap osmoticum for osmoregulation.
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Affiliation(s)
- Babar Shahzad
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas. 7001, Australia
| | - Ping Yun
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas. 7001, Australia
| | - Lana Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas. 7001, Australia
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas. 7001, Australia
| | - Gothandapani Sellamuthu
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai 600113, India; and Forest Molecular Entomology Laboratory, Excellent Team for Mitigation (ETM), Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague 16500, Czech Republic
| | - Gayatri Venkataraman
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai 600113, India
| | - Zhong-Hua Chen
- School of Science, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas. 7001, Australia; and International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
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Ishikawa T, Shabala L, Zhou M, Venkataraman G, Yu M, Sellamuthu G, Chen ZH, Shabala S. Comparative Analysis of Root Na+ Relation under Salinity between Oryza sativa and Oryza coarctata. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11050656. [PMID: 35270125 PMCID: PMC8912616 DOI: 10.3390/plants11050656] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 02/23/2022] [Accepted: 02/23/2022] [Indexed: 06/01/2023]
Abstract
Na+ toxicity is one of the major physiological constraints imposed by salinity on plant performance. At the same time, Na+ uptake may be beneficial under some circumstances as an easily accessible inorganic ion that can be used for increasing solute concentrations and maintaining cell turgor. Two rice species, Oryza sativa (cultivated rice, salt-sensitive) and Oryza coarctata (wild rice, salt-tolerant), demonstrated different strategies in controlling Na+ uptake. Glasshouse experiments and gene expression analysis suggested that salt-treated wild rice quickly increased xylem Na+ loading for osmotic adjustment but maintained a non-toxic level of stable shoot Na+ concentration by increased activity of a high affinity K+ transporter HKT1;5 (essential for xylem Na+ unloading) and a Na+/H+ exchanger NHX (for sequestering Na+ and K+ into root vacuoles). Cultivated rice prevented Na+ uptake and transport to the shoot at the beginning of salt treatment but failed to maintain it in the long term. While electrophysiological assays revealed greater net Na+ uptake upon salt application in cultivated rice, O. sativa plants showed much stronger activation of the root plasma membrane Na+/H+ Salt Overly Sensitive 1 (SOS1) exchanger. Thus, it appears that wild rice limits passive Na+ entry into root cells while cultivated rice relies heavily on SOS1-mediating Na+ exclusion, with major penalties imposed by the existence of the "futile cycle" at the plasma membrane.
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Affiliation(s)
- Tetsuya Ishikawa
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7005, Australia; (T.I.); (L.S.); (M.Z.)
| | - Lana Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7005, Australia; (T.I.); (L.S.); (M.Z.)
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7005, Australia; (T.I.); (L.S.); (M.Z.)
| | - Gayatri Venkataraman
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai 600113, India; (G.V.); (G.S.)
| | - Min Yu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China;
| | - Gothandapani Sellamuthu
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai 600113, India; (G.V.); (G.S.)
- Forest Molecular Entomology Lab, Excellent Team for Mitigation (ETM), Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, 16500 Prague, Czech Republic
| | - Zhong-Hua Chen
- School of Science, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia;
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7005, Australia; (T.I.); (L.S.); (M.Z.)
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China;
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8
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Malakar P, Chattopadhyay D. Adaptation of plants to salt stress: the role of the ion transporters. JOURNAL OF PLANT BIOCHEMISTRY AND BIOTECHNOLOGY 2021; 30:668-683. [PMID: 0 DOI: 10.1007/s13562-021-00741-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/28/2021] [Indexed: 05/27/2023]
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9
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Venkataraman G, Shabala S, Véry AA, Hariharan GN, Somasundaram S, Pulipati S, Sellamuthu G, Harikrishnan M, Kumari K, Shabala L, Zhou M, Chen ZH. To exclude or to accumulate? Revealing the role of the sodium HKT1;5 transporter in plant adaptive responses to varying soil salinity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 169:333-342. [PMID: 34837866 DOI: 10.1016/j.plaphy.2021.11.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/13/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
Arid/semi-arid and coastal agricultural areas of the world are especially vulnerable to climate change-driven soil salinity. Salinity tolerance in plants is a complex trait, with salinity negatively affecting crop yield. Plants adopt a range of mechanisms to combat salinity, with many transporter genes being implicated in Na+-partitioning processes. Within these, the high-affinity K+ (HKT) family of transporters play a critical role in K+ and Na+ homeostasis in plants. Among HKT transporters, Type I transporters are Na+-specific. While Arabidopsis has only one Na + -specific HKT (AtHKT1;1), cereal crops have a multiplicity of Type I and II HKT transporters. AtHKT1; 1 (Arabidopsis thaliana) and HKT1; 5 (cereal crops) 'exclude' Na+ from the xylem into xylem parenchyma in the root, reducing shoot Na+ and hence, confer sodium tolerance. However, more recent data from Arabidopsis and crop species show that AtHKT1;1/HKT1;5 alleles have a strong genetic association with 'shoot sodium accumulation' and concomitant salt tolerance. The review tries to resolve these two seemingly contradictory effects of AtHKT1;1/HKT1;5 operation (shoot exclusion vs shoot accumulation), both conferring salinity tolerance and suggests that contrasting phenotypes are attributable to either hyper-functional or weak AtHKT1;1/HKT1;5 alleles/haplotypes and are under strong selection by soil salinity levels. It also suggests that opposite balancing mechanisms involving xylem ion loading in these contrasting phenotypes exist that require transporters such as SOS1 and CCC. While HKT1; 5 is a crucial but not sole determinant of salinity tolerance, investigation of the adaptive benefit(s) conferred by naturally occurring intermediate HKT1;5 alleles will be important under a climate change scenario.
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Affiliation(s)
- Gayatri Venkataraman
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India.
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 98, Hobart, Tas, 7001, Australia; International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, 528000, China.
| | - Anne-Aliénor Véry
- Biochimie & Physiologie Moléculaire des Plantes, UMR Univ. Montpellier, CNRS, INRAE, Institut Agro, 34060, Montpellier Cedex 2, France.
| | - Gopalasamudram Neelakantan Hariharan
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India
| | - Suji Somasundaram
- Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, 600124, India
| | - Shalini Pulipati
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India
| | - Gothandapani Sellamuthu
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India; Forest Molecular Entomology Laboratory, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague (CZU), Kamycka 129, Praha, 16500, Czech Republic
| | - Mohan Harikrishnan
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India
| | - Kumkum Kumari
- Plant Molecular Biology Laboratory, M. S. Swaminathan Research Foundation, III Cross Street, Taramani Institutional Area, Chennai, 600113, India
| | - Lana Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 98, Hobart, Tas, 7001, Australia
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 98, Hobart, Tas, 7001, Australia
| | - Zhong-Hua Chen
- School of Science, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
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10
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Electrical Signaling of Plants under Abiotic Stressors: Transmission of Stimulus-Specific Information. Int J Mol Sci 2021; 22:ijms221910715. [PMID: 34639056 PMCID: PMC8509212 DOI: 10.3390/ijms221910715] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/16/2022] Open
Abstract
Plants have developed complex systems of perception and signaling to adapt to changing environmental conditions. Electrical signaling is one of the most promising candidates for the regulatory mechanisms of the systemic functional response under the local action of various stimuli. Long-distance electrical signals of plants, such as action potential (AP), variation potential (VP), and systemic potential (SP), show specificities to types of inducing stimuli. The systemic response induced by a long-distance electrical signal, representing a change in the activity of a complex of molecular-physiological processes, includes a nonspecific component and a stimulus-specific component. This review discusses possible mechanisms for transmitting information about the nature of the stimulus and the formation of a specific systemic response with the participation of electrical signals induced by various abiotic factors.
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Shen Y, He F, Zhu J, Zhang H, Wang J, Wang H, Zhan X. Proton-coupled cotransporter involves phenanthrene xylem loading in roots. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 773:145637. [PMID: 33582351 DOI: 10.1016/j.scitotenv.2021.145637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/31/2021] [Accepted: 01/31/2021] [Indexed: 06/12/2023]
Abstract
The uptake and translocation of polycyclic aromatic hydrocarbons (PAHs) by staple crops have gained much attention. However, the mechanism on phenanthrene xylem loading across plasma membrane is still unclear. In this study, we investigated the concentration dependence of phenanthrene xylem loading and the relationship between phenanthrene concentration and xylem sap pH. The impacts of metabolic inhibitor, temperature, and dissolved oxygen on phenanthrene concentration in xylem sap were observed as well. The Michaelis-Menten equation fits phenanthrene xylem loading across parenchyma cell membrane well and xylem sap pH decreases with the increase in treated phenanthrene concentration. Metabolic inhibitor, low temperature and low dissolved oxygen can suppress phenanthrene loading into xylem sap. The inhibitory rate of sodium vanadate on xylem sap phenanthrene is between 19.76% and 25.82%. Low temperature reduces phenanthrene concentration in xylem sap by 86.68%. Hypoxia (2 mg L-1) inhibits phenanthrene loading into xylem by 78.67%. Therefore, it is indicated that H+/phenanthrene cotransporter is implicated in phenanthrene loading into xylem. Our work offers a valuable model to understand the mechanism of PAH loading into xylem.
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Affiliation(s)
- Yu Shen
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Fang He
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Jiahui Zhu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Huihui Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Jia Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Huiqian Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China
| | - Xinhua Zhan
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, PR China.
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Wu Q, Su N, Huang X, Cui J, Shabala L, Zhou M, Yu M, Shabala S. Hypoxia-induced increase in GABA content is essential for restoration of membrane potential and preventing ROS-induced disturbance to ion homeostasis. PLANT COMMUNICATIONS 2021; 2:100188. [PMID: 34027398 PMCID: PMC8132176 DOI: 10.1016/j.xplc.2021.100188] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 04/07/2021] [Accepted: 04/28/2021] [Indexed: 05/03/2023]
Abstract
When plants are exposed to hypoxic conditions, the level of γ-aminobutyric acid (GABA) in plant tissues increases by several orders of magnitude. The physiological rationale behind this elevation remains largely unanswered. By combining genetic and electrophysiological approach, in this work we show that hypoxia-induced increase in GABA content is essential for restoration of membrane potential and preventing ROS-induced disturbance to cytosolic K+ homeostasis and Ca2+ signaling. We show that reduced O2 availability affects H+-ATPase pumping activity, leading to membrane depolarization and K+ loss via outward-rectifying GORK channels. Hypoxia stress also results in H2O2 accumulation in the cell that activates ROS-inducible Ca2+ uptake channels and triggers self-amplifying "ROS-Ca hub," further exacerbating K+ loss via non-selective cation channels that results in the loss of the cell's viability. Hypoxia-induced elevation in the GABA level may restore membrane potential by pH-dependent regulation of H+-ATPase and/or by generating more energy through the activation of the GABA shunt pathway and TCA cycle. Elevated GABA can also provide better control of the ROS-Ca2+ hub by transcriptional control of RBOH genes thus preventing over-excessive H2O2 accumulation. Finally, GABA can operate as a ligand directly controlling the open probability and conductance of K+ efflux GORK channels, thus enabling plants adaptation to hypoxic conditions.
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Affiliation(s)
- Qi Wu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
- Institute of Crop Germplasm and Biotechnology, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Nana Su
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xin Huang
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
| | - Jin Cui
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lana Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
| | - Meixue Zhou
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
| | - Min Yu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
- Corresponding author
| | - Sergey Shabala
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS 7001, Australia
- Corresponding author
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Gupta A, Shaw BP. Augmenting salt tolerance in rice by regulating uptake and tissue specific accumulation of Na + - through Ca 2+ -induced alteration of biochemical events. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23 Suppl 1:122-130. [PMID: 33768704 DOI: 10.1111/plb.13258] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/14/2021] [Indexed: 05/27/2023]
Abstract
The protective effect of Ca2+ against NaCl toxicity was investigated in two rice varieties with contrasting for salt tolerance to understand the mechanistic details of the antagonism to address adverse effects of salinity on agriculture. The study primarily examined the influence of Ca2+ on expression/activity of the effectors and regulators involved in Na+ translocation. Calcium reduced uptake of Na+ concomitant with higher tissue K+ /Na+ in seedlings, comparatively more in salt-tolerant Nona Bokra than in salt-sensitive IR-64, together with a significant increase in root PM H+ ATPase in the former, but not in the latter. Increased antagonism in Nona Bokra could be the result of Ca2+ signalling-mediated phosphorylation of PM H+ ATPase in roots caused by a significant Ca2+ -dependent increase in expression of OsCIPK24, which did not occur in IR-64. Furthermore, significant Ca2+ -mediated NaCl-induced increase in transcription of 14-3-3 protein in Nona Bokra, but not in IR-64, might also lead to a greater protective effect of Ca2+ in the former, as 14-3-3 protein is essential for activating PM H+ ATPase. Thus, efficient functioning of PM H+ ATPase could be key in determining resistance of plants to salinity, implying that identification of the Ca2+ -dependent kinase phosphorylating the PM H+ ATPase threonine residue and manipulation of its expression, together with expression of 14-3-3 proteins could be an important strategy to improve salt tolerance of crops and their cultivation in salt-affected lands.
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Affiliation(s)
- A Gupta
- Abiotic Stress and Agro-Biotechnology Laboratory, Institute of Life Sciences, Nalco Square, Bhubaneswar, 751023, Odisha, India
- Regional Centre for Biotechnology, Faridabad, 121001, Haryana, India
| | - B P Shaw
- Abiotic Stress and Agro-Biotechnology Laboratory, Institute of Life Sciences, Nalco Square, Bhubaneswar, 751023, Odisha, India
- Regional Centre for Biotechnology, Faridabad, 121001, Haryana, India
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Chu M, Chen P, Meng S, Xu P, Lan W. The Arabidopsis phosphatase PP2C49 negatively regulates salt tolerance through inhibition of AtHKT1;1. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:528-542. [PMID: 32877013 DOI: 10.1111/jipb.13008] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/31/2020] [Indexed: 05/08/2023]
Abstract
Type 2C protein phosphatases (PP2Cs) are the largest protein phosphatase family. PP2Cs dephosphorylate substrates for signaling in Arabidopsis, but the functions of most PP2Cs remain unknown. Here, we characterized PP2C49 (AT3G62260, a Group G PP2C), which regulates Na+ distribution under salt stress and is localized to the cytoplasm and nucleus. PP2C49 was highly expressed in root vascular tissues and its disruption enhanced plant tolerance to salt stress. Compared with wild type, the pp2c49 mutant contained more Na+ in roots but less Na+ in shoots and xylem sap, suggesting that PP2C49 regulates shoot Na+ extrusion. Reciprocal grafting revealed a root-based mechanism underlying the salt tolerance of pp2c49. Systemic Na+ distribution largely depends on AtHKT1;1 and loss of function of AtHKT1;1 in the pp2c49 background overrode the salt tolerance of pp2c49, resulting in salt sensitivity. Furthermore, compared with plants overexpressing PP2C49 in the wild-type background, plants overexpressing PP2C49 in the athtk1;1 mutant background were sensitive to salt, like the athtk1;1 mutants. Moreover, protein-protein interaction and two-voltage clamping assays demonstrated that PP2C49 physically interacts with AtHKT1;1 and inhibits the Na+ permeability of AtHKT1;1. This study reveals that PP2C49 negatively regulates AtHKT1;1 activity and thus determines systemic Na+ allocation during salt stress.
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Affiliation(s)
- Moli Chu
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Pengwang Chen
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Sufang Meng
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Peng Xu
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Wenzhi Lan
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China
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Gupta A, Shaw BP. Biochemical and molecular characterisations of salt tolerance components in rice varieties tolerant and sensitive to NaCl: the relevance of Na + exclusion in salt tolerance in the species. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 48:72-87. [PMID: 32727653 DOI: 10.1071/fp20089] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
Soil salinisation is a major abiotic stress in agriculture, and is especially a concern for rice production because among cereal crops, rice is the most salt-sensitive. However, the production of rice must be increased substantially by the year 2050 to meet the demand of the ever growing population. Hence, understanding the biochemical events determining salt tolerance in rice is highly desirable so that the trait can be introduced in cultivars of interest through biotechnological intervention. In this context, an initial study on NaCl response in four Indica rice varieties showed a lower uptake of Na+ in the salt-tolerant Nona Bokra and Pokkali than in the salt-sensitive IR64 and IR29, indicating Na+ exclusion as a primary requirement of salt tolerance in the species. This was also supported by the following features in the salt-tolerant, but not in the -sensitive varieties: (1) highly significant NaCl-induced increase in the activity of PM-H+ATPase, (2) a high constitutive level and NaCl-induced threonine phosphorylation of PM-H+ATPase, necessary to promote its activity, (3) a high constitutive expression of 14-3-3 protein that makes PM-H+ATPase active by binding with the phosphorylated threonine at the C-terminal end, (4) a high constitutive and NaCl-induced expression of SOS1 in roots, and (5) significant NaCl-induced expression of OsCIPK 24, a SOS2 that phosphorylates SOS1. The vacuolar sequestration of Na+ in seedlings was not reflected from the expression pattern of NHX1/NHX1 in response to NaCl. NaCl-induced downregulation of expression of HKTs in roots of Nona Bokra, but upregulation in Pokkali also indicates that their role in salt tolerance in rice could be cultivar specific. The study indicates that consideration of increasing exclusion of Na+ by enhancing the efficiency of SOS1/PM-H+ATPase Na+ exclusion module could be an important aspect in attempting to increase salt tolerance in the rice varieties or cultivars of interest.
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Affiliation(s)
- Amber Gupta
- Abiotic Stress and Agro-Biotechnology Laboratory, Institute of Life Sciences, Nalco Square, Bhubaneswar 751023, Odisha, India
| | - Birendra P Shaw
- Abiotic Stress and Agro-Biotechnology Laboratory, Institute of Life Sciences, Nalco Square, Bhubaneswar 751023, Odisha, India; and Corresponding author.
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16
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Comprehensive proteomic analysis revealing multifaceted regulatory network of the xero-halophyte Haloxylon salicornicum involved in salt tolerance. J Biotechnol 2020; 324:143-161. [DOI: 10.1016/j.jbiotec.2020.10.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/29/2020] [Accepted: 10/09/2020] [Indexed: 01/06/2023]
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17
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Zarza X, Van Wijk R, Shabala L, Hunkeler A, Lefebvre M, Rodriguez‐Villalón A, Shabala S, Tiburcio AF, Heilmann I, Munnik T. Lipid kinases PIP5K7 and PIP5K9 are required for polyamine-triggered K + efflux in Arabidopsis roots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:416-432. [PMID: 32666545 PMCID: PMC7693229 DOI: 10.1111/tpj.14932] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/30/2020] [Accepted: 07/07/2020] [Indexed: 05/03/2023]
Abstract
Polyamines, such as putrescine, spermidine and spermine (Spm), are low-molecular-weight polycationic molecules present in all living organisms. Despite their implication in plant cellular processes, little is known about their molecular mode of action. Here, we demonstrate that polyamines trigger a rapid increase in the regulatory membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2 ), and that this increase is required for polyamine effects on K+ efflux in Arabidopsis roots. Using in vivo 32 Pi -labelling of Arabidopsis seedlings, low physiological (μm) concentrations of Spm were found to promote a rapid PIP2 increase in roots that was time- and dose-dependent. Confocal imaging of a genetically encoded PIP2 biosensor revealed that this increase was triggered at the plasma membrane. Differential 32 Pi -labelling suggested that the increase in PIP2 was generated through activation of phosphatidylinositol 4-phosphate 5-kinase (PIP5K) activity rather than inhibition of a phospholipase C or PIP2 5-phosphatase activity. Systematic analysis of transfer DNA insertion mutants identified PIP5K7 and PIP5K9 as the main candidates involved in the Spm-induced PIP2 response. Using non-invasive microelectrode ion flux estimation, we discovered that the Spm-triggered K+ efflux response was strongly reduced in pip5k7 pip5k9 seedlings. Together, our results provide biochemical and genetic evidence for a physiological role of PIP2 in polyamine-mediated signalling controlling K+ flux in plants.
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Affiliation(s)
- Xavier Zarza
- Research Cluster Green Life SciencesSection Plant Cell BiologySwammerdam Institute for Life SciencesUniversity of AmsterdamPO Box 94215Amsterdam1090 GEThe Netherlands
| | - Ringo Van Wijk
- Research Cluster Green Life SciencesSection Plant Cell BiologySwammerdam Institute for Life SciencesUniversity of AmsterdamPO Box 94215Amsterdam1090 GEThe Netherlands
| | - Lana Shabala
- Tasmanian Institute of AgricultureUniversity of TasmaniaHobartAustralia
| | - Anna Hunkeler
- Department of BiologyInstitute of Agricultural ScienceSwiss Federal Institute of Technology in ZurichZurichSwitzerland
| | - Matthew Lefebvre
- Research Cluster Green Life SciencesSection Plant Cell BiologySwammerdam Institute for Life SciencesUniversity of AmsterdamPO Box 94215Amsterdam1090 GEThe Netherlands
| | - Antia Rodriguez‐Villalón
- Department of BiologyInstitute of Agricultural ScienceSwiss Federal Institute of Technology in ZurichZurichSwitzerland
| | - Sergey Shabala
- Tasmanian Institute of AgricultureUniversity of TasmaniaHobartAustralia
- International Research Centre for Environmental Membrane BiologyFoshan UniversityFoshanChina
| | - Antonio F. Tiburcio
- Dept. of Natural Products, Plant Biology and Soil ScienceUniversity of BarcelonaBarcelonaSpain
| | - Ingo Heilmann
- Dept of Cellular BiochemistryInstitute of Biochemistry and BiotechnologyMartin Luther University Halle‐WittenbergHalle (Saale)Germany
| | - Teun Munnik
- Research Cluster Green Life SciencesSection Plant Cell BiologySwammerdam Institute for Life SciencesUniversity of AmsterdamPO Box 94215Amsterdam1090 GEThe Netherlands
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Queiroz CSD, Pereira IMC, Lima KRP, Bret RSC, Alves MS, Gomes-Filho E, Carvalho HHD. Combined NaCl and DTT diminish harmful ER-stress effects in the sorghum seedlings CSF 20 variety. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 147:223-234. [PMID: 31874339 DOI: 10.1016/j.plaphy.2019.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/27/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
Plants have developed mechanisms to avoid harmful effects of Na+ accumulation, such as the signaling pathway of carrier proteins Na+/H+ (NHX) and salt overly sensitive (SOS). Besides, endoplasmic reticulum (ER) could integrate plant cell response. Thus, we aimed to understand the effects of ER homeostasis impairment, and its relationship to salt stress during early stages of the Sorghum bicolor CSF 20 a salt-tolerant variety. Three days old seedlings were challenged with NaCl (0, 50, 75 and 100 mM), dithiothreitol (DTT) at 0, 2.5, 5.0 10.0 mM, and the combined NaCl and DTT treatments. Tunicamycin (TUN) was also used as a second inducer of ER stress in a quantitative PCR, to corroborate with DTT's results. There was no significant change in growth parameters under NaCl treatments. Nevertheless, seedling length, mass and Na+ content were decreased as DTT concentration was increased. Under combined NaCl and DTT treatments, shoot length and fresh and dry masses were maintained at control levels. On the other hand, the levels of Na+ were decreased, in comparison to NaCl treatment. Genes analyzed by qPCR revealed that NaCl was able to induce all of them, except for SbbZIP60, however it was induced under combined stresses. In conclusion, the results indicated that S. bicolor seedlings of CSF 20 variety were tolerant to salt and sensible to ER stress. The combination of both stresses restored the ER homeostasis promoting a decrease of Na+ content via the membrane transporters SbNHX1, SbSOS1, and SbPDI ER-chaperone and the ER sensor SbbZIP60.
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Affiliation(s)
- Cinthia Silva de Queiroz
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
| | - Isabelle Mary Costa Pereira
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
| | - Karollyny Roger Pereira Lima
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
| | - Raissa Souza Caminha Bret
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
| | - Murilo Siqueira Alves
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
| | - Enéas Gomes-Filho
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil; Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciências e Tecnologia em Salinidade (INCTSal/CNPq), Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60455-760, Brazil.
| | - Humberto Henrique de Carvalho
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, CE, 60440-554, Brazil.
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Zarei M, Shabala S, Zeng F, Chen X, Zhang S, Azizi M, Rahemi M, Davarpanah S, Yu M, Shabala L. Comparing Kinetics of Xylem Ion Loading and Its Regulation in Halophytes and Glycophytes. PLANT & CELL PHYSIOLOGY 2020; 61:403-415. [PMID: 31693150 DOI: 10.1093/pcp/pcz205] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 10/29/2019] [Indexed: 05/02/2023]
Abstract
Although control of xylem ion loading is essential to confer salinity stress tolerance, specific details behind this process remain elusive. In this work, we compared the kinetics of xylem Na+ and K+ loading between two halophytes (Atriplex lentiformis and quinoa) and two glycophyte (pea and beans) species, to understand the mechanistic basis of the above process. Halophyte plants had high initial amounts of Na+ in the leaf, even when grown in the absence of the salt stress. This was matched by 7-fold higher xylem sap Na+ concentration compared with glycophyte plants. Upon salinity exposure, the xylem sap Na+ concentration increased rapidly but transiently in halophytes, while in glycophytes this increase was much delayed. Electrophysiological experiments using the microelectrode ion flux measuring technique showed that glycophyte plants tend to re-absorb Na+ back into the stele, thus reducing xylem Na+ load at the early stages of salinity exposure. The halophyte plants, however, were capable to release Na+ even in the presence of high Na+ concentrations in the xylem. The presence of hydrogen peroxide (H2O2) [mimicking NaCl stress-induced reactive oxygen species (ROS) accumulation in the root] caused a massive Na+ and Ca2+ uptake into the root stele, while triggering a substantial K+ efflux from the cytosol into apoplast in glycophyte but not halophytes species. The peak in H2O2 production was achieved faster in halophytes (30 min vs 4 h) and was attributed to the increased transcript levels of RbohE. Pharmacological data suggested that non-selective cation channels are unlikely to play a major role in ROS-mediated xylem Na+ loading.
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Affiliation(s)
- Mahvash Zarei
- Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Sergey Shabala
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
| | - Fanrong Zeng
- Agronomy Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xiaohui Chen
- Agronomy Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Shuo Zhang
- Agronomy Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Majid Azizi
- Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Majid Rahemi
- Department of Horticultural Science, Faculty of Agriculture, Shiraz University, Shiraz, Iran
| | - Sohrab Davarpanah
- Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Min Yu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
| | - Lana Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
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20
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Su N, Wu Q, Chen J, Shabala L, Mithöfer A, Wang H, Qu M, Yu M, Cui J, Shabala S. GABA operates upstream of H+-ATPase and improves salinity tolerance in Arabidopsis by enabling cytosolic K+ retention and Na+ exclusion. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:6349-6361. [PMID: 31420662 PMCID: PMC6859739 DOI: 10.1093/jxb/erz367] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 08/02/2019] [Indexed: 05/19/2023]
Abstract
The non-protein amino acid γ-aminobutyric acid (GABA) rapidly accumulates in plant tissues in response to salinity. However, the physiological rationale for this elevation remains elusive. This study compared electrophysiological and whole-plant responses of salt-treated Arabidopsis mutants pop2-5 and gad1,2, which have different abilities to accumulate GABA. The pop2-5 mutant, which was able to overaccumulate GABA in its roots, showed a salt-tolerant phenotype. On the contrary, the gad1,2 mutant, lacking the ability to convert glutamate to GABA, showed oversensitivity to salinity. The greater salinity tolerance of the pop2-5 line was explained by: (i) the role of GABA in stress-induced activation of H+-ATPase, thus leading to better membrane potential maintenance and reduced stress-induced K+ leak from roots; (ii) reduced rates of net Na+ uptake; (iii) higher expression of SOS1 and NHX1 genes in the leaves, which contributed to reducing Na+ concentration in the cytoplasm by excluding Na+ to apoplast and sequestering Na+ in the vacuoles; (iv) a lower rate of H2O2 production and reduced reactive oxygen species-inducible K+ efflux from root epidermis; and (v) better K+ retention in the shoot associated with the lower expression level of GORK channels in plant leaves.
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Affiliation(s)
- Nana Su
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Qi Wu
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
| | - Jiahui Chen
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lana Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Axel Mithöfer
- Research Group of Plant Defense Physiology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Haiyang Wang
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Mei Qu
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Min Yu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
| | - Jin Cui
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Sergey Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
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21
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Huang Y, Cao H, Yang L, Chen C, Shabala L, Xiong M, Niu M, Liu J, Zheng Z, Zhou L, Peng Z, Bie Z, Shabala S. Tissue-specific respiratory burst oxidase homolog-dependent H2O2 signaling to the plasma membrane H+-ATPase confers potassium uptake and salinity tolerance in Cucurbitaceae. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:5879-5893. [PMID: 31290978 PMCID: PMC6812723 DOI: 10.1093/jxb/erz328] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/03/2019] [Indexed: 05/02/2023]
Abstract
Potassium (K+) is a critical determinant of salinity tolerance, and H2O2 has been recognized as an important signaling molecule that mediates many physiological responses. However, the details of how H2O2 signaling regulates K+ uptake in the root under salt stress remain elusive. In this study, salt-sensitive cucumber and salt-tolerant pumpkin which belong to the same family, Cucurbitaceae, were used to answer the above question. We show that higher salt tolerance in pumpkin was related to its superior ability for K+ uptake and higher H2O2 accumulation in the root apex. Transcriptome analysis showed that salinity induced 5816 (3005 up- and 2811 down-) and 4679 (3965 up- and 714 down-) differentially expressed genes (DEGs) in cucumber and pumpkin, respectively. DEGs encoding NADPH oxidase (respiratory burst oxidase homolog D; RBOHD), 14-3-3 protein (GRF12), plasma membrane H+-ATPase (AHA1), and potassium transporter (HAK5) showed higher expression in pumpkin than in cucumber under salinity stress. Treatment with the NADPH oxidase inhibitor diphenylene iodonium resulted in lower RBOHD, GRF12, AHA1, and HAK5 expression, reduced plasma membrane H+-ATPase activity, and lower K+ uptake, leading to a loss of the salinity tolerance trait in pumpkin. The opposite results were obtained when the plants were pre-treated with exogenous H2O2. Knocking out of RBOHD in pumpkin by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9] editing of coding sequences resulted in lower root apex H2O2 and K+ content and GRF12, AHA1, and HAK5 expression, ultimately resulting in a salt-sensitive phenotype. However, ectopic expression of pumpkin RBOHD in Arabidopsis led to the opposite effect. Taken together, this study shows that RBOHD-dependent H2O2 signaling in the root apex is important for pumpkin salt tolerance and suggests a novel mechanism that confers this trait, namely RBOHD-mediated transcriptional and post-translational activation of plasma membrane H+-ATPase operating upstream of HAK5 K+ uptake transporters.
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Affiliation(s)
- Yuan Huang
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania, Australia
| | - Haishun Cao
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Li Yang
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Chen Chen
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Lana Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania, Australia
| | - Mu Xiong
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Mengliang Niu
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Juan Liu
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania, Australia
| | - Zuhua Zheng
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Lijian Zhou
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Zhaowen Peng
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Zhilong Bie
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, PR China
| | - Sergey Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, PR China
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22
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23
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Ishikawa T, Shabala S. Control of xylem Na + loading and transport to the shoot in rice and barley as a determinant of differential salinity stress tolerance. PHYSIOLOGIA PLANTARUM 2019; 165:619-631. [PMID: 29761494 DOI: 10.1111/ppl.12758] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/10/2018] [Indexed: 06/08/2023]
Abstract
Control of xylem Na+ loading has often been named as the essential component of salinity tolerance mechanism. However, it is less clear to what extent the difference in this trait may determine differential salinity tolerance between species. In this study, barley (Hordeum vulgare L. cv. CM72) and rice (Oryza sativa L. cv. Dongjin) plants were grown under two levels of salinity. Na+ and K+ concentrations in the xylem sap, and shoot and root tissues were measured at different time points after stress onset. Salt-exposed rice plants prevented xylem Na+ loading for several days, but failed to control this process in the longer term, ultimately resulting in a massive Na+ shoot loading. Barley plants quickly increased xylem Na+ concentration and its delivery to the shoot (most likely for the purpose of osmotic adjustment) but were able to reduce this process later on, keeping most of accumulated Na+ in the root, thus maintaining non-toxic shoot Na+ level. Rice plants increased shoot K+ concentration, while barley plants maintained higher root K+ concentration. Control of xylem Na+ loading is remarkably different between rice and barley; this difference may differentiate the extent of the salinity tolerance between species. This trait should be investigated in more detail to be used in the breeding programs aimed to improve salinity tolerance in crops.
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Affiliation(s)
- Tetsuya Ishikawa
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Sergey Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania 7001, Australia
- Department of Horticulture, Foshan University, Foshan 528000, China
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24
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Isayenkov SV, Maathuis FJM. Plant Salinity Stress: Many Unanswered Questions Remain. FRONTIERS IN PLANT SCIENCE 2019; 10:80. [PMID: 30828339 PMCID: PMC6384275 DOI: 10.3389/fpls.2019.00080] [Citation(s) in RCA: 390] [Impact Index Per Article: 78.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 01/18/2019] [Indexed: 05/19/2023]
Abstract
Salinity is a major threat to modern agriculture causing inhibition and impairment of crop growth and development. Here, we not only review recent advances in salinity stress research in plants but also revisit some basic perennial questions that still remain unanswered. In this review, we analyze the physiological, biochemical, and molecular aspects of Na+ and Cl- uptake, sequestration, and transport associated with salinity. We discuss the role and importance of symplastic versus apoplastic pathways for ion uptake and critically evaluate the role of different types of membrane transporters in Na+ and Cl- uptake and intercellular and intracellular ion distribution. Our incomplete knowledge regarding possible mechanisms of salinity sensing by plants is evaluated. Furthermore, a critical evaluation of the mechanisms of ion toxicity leads us to believe that, in contrast to currently held ideas, toxicity only plays a minor role in the cytosol and may be more prevalent in the vacuole. Lastly, the multiple roles of K+ in plant salinity stress are discussed.
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Affiliation(s)
- Stanislav V. Isayenkov
- Department of Plant Food Products and Biofortification, Institute of Food Biotechnology and Genomics NAS of Ukraine, Kyiv, Ukraine
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25
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The Complex Fine-Tuning of K⁺ Fluxes in Plants in Relation to Osmotic and Ionic Abiotic Stresses. Int J Mol Sci 2019; 20:ijms20030715. [PMID: 30736441 PMCID: PMC6387338 DOI: 10.3390/ijms20030715] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/17/2019] [Accepted: 01/29/2019] [Indexed: 12/19/2022] Open
Abstract
As the main cation in plant cells, potassium plays an essential role in adaptive responses, especially through its involvement in osmotic pressure and membrane potential adjustments. K+ homeostasis must, therefore, be finely controlled. As a result of different abiotic stresses, especially those resulting from global warming, K⁺ fluxes and plant distribution of this ion are disturbed. The hormone abscisic acid (ABA) is a key player in responses to these climate stresses. It triggers signaling cascades that ultimately lead to modulation of the activities of K⁺ channels and transporters. After a brief overview of transcriptional changes induced by abiotic stresses, this review deals with the post-translational molecular mechanisms in different plant organs, in Arabidopsis and species of agronomical interest, triggering changes in K⁺ uptake from the soil, K⁺ transport and accumulation throughout the plant, and stomatal regulation. These modifications involve phosphorylation/dephosphorylation mechanisms, modifications of targeting, and interactions with regulatory partner proteins. Interestingly, many signaling pathways are common to K⁺ and Cl-/NO3- counter-ion transport systems. These cross-talks are also addressed.
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26
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Bazihizina N, Colmer TD, Cuin TA, Mancuso S, Shabala S. Friend or Foe? Chloride Patterning in Halophytes. TRENDS IN PLANT SCIENCE 2019; 24:142-151. [PMID: 30558965 DOI: 10.1016/j.tplants.2018.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/11/2018] [Accepted: 11/16/2018] [Indexed: 06/09/2023]
Abstract
In this opinion article, we challenge the traditional view that breeding for reduced Cl- uptake would benefit plant salinity tolerance. A negative correlation between shoot Cl- concentration and plant biomass does not hold for halophytes - naturally salt tolerant species. We argue that, under physiologically relevant conditions, Cl- uptake requires plants to invest metabolic energy, and that the poor selectivity of Cl--transporting proteins may explain the reported negative correlation between Cl- accumulation and crop salinity tolerance. We propose a new paradigm: salinity tolerance could be achieved by improving the selectivity of some of the broadly selective anion-transporting proteins (e.g., for NO3->Cl-), alongside tight control of Cl- uptake, rather than targeting traits mediating its efflux from the root.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy; Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.
| | - Timothy D Colmer
- UWA School of Agriculture and Environment, Faculty of Science, University of Western Australia (UWA), 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Tracey Ann Cuin
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.
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27
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Zarza X, Shabala L, Fujita M, Shabala S, Haring MA, Tiburcio AF, Munnik T. Extracellular Spermine Triggers a Rapid Intracellular Phosphatidic Acid Response in Arabidopsis, Involving PLDδ Activation and Stimulating Ion Flux. FRONTIERS IN PLANT SCIENCE 2019; 10:601. [PMID: 31178874 PMCID: PMC6537886 DOI: 10.3389/fpls.2019.00601] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/24/2019] [Indexed: 05/19/2023]
Abstract
Polyamines, such as putrescine (Put), spermidine (Spd), and spermine (Spm), are low-molecular-weight polycationic molecules found in all living organisms. Despite the fact that they have been implicated in various important developmental and adaptative processes, their mode of action is still largely unclear. Here, we report that Put, Spd, and Spm trigger a rapid increase in the signaling lipid, phosphatidic acid (PA) in Arabidopsis seedlings but also mature leaves. Using time-course and dose-response experiments, Spm was found to be the most effective; promoting PA responses at physiological (low μM) concentrations. In seedlings, the increase of PA occurred mainly in the root and partly involved the plasma membrane polyamine-uptake transporter (PUT), RMV1. Using a differential 32Pi-labeling strategy combined with transphosphatidylation assays and T-DNA insertion mutants, we found that phospholipase D (PLD), and in particular PLDδ was the main contributor of the increase in PA. Measuring non-invasive ion fluxes (MIFE) across the root plasma membrane of wild type and pldδ-mutant seedlings, revealed that the formation of PA is linked to a gradual- and transient efflux of K+. Potential mechanisms of how PLDδ and the increase of PA are involved in polyamine function is discussed.
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Affiliation(s)
- Xavier Zarza
- Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
- Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Lana Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Miki Fujita
- Gene Discovery Research Group, RIKEN Plant Science Center, Tsukuba, Japan
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Michel A. Haring
- Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Antonio F. Tiburcio
- Department of Biology, Healthcare and the Environment, Faculty of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Teun Munnik
- Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
- Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
- *Correspondence: Teun Munnik,
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28
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Liu J, Shabala S, Shabala L, Zhou M, Meinke H, Venkataraman G, Chen Z, Zeng F, Zhao Q. Tissue-Specific Regulation of Na + and K + Transporters Explains Genotypic Differences in Salinity Stress Tolerance in Rice. FRONTIERS IN PLANT SCIENCE 2019; 10:1361. [PMID: 31737000 PMCID: PMC6838216 DOI: 10.3389/fpls.2019.01361] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/03/2019] [Indexed: 05/20/2023]
Abstract
Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is highly sensitive to soil salinity, current trends in soil salinization threaten global food security. To better understand the mechanistic basis of salinity tolerance in rice, three contrasting rice cultivars-Reiziq (tolerant), Doongara (moderately tolerant), and Koshihikari (sensitive)-were examined and the differences in operation of key ion transporters mediating ionic homeostasis in these genotypes were evaluated. Tolerant varieties had reduced Na+ translocation from roots to shoots. Electrophysiological and quantitative reverse transcription PCR experiments showed that tolerant genotypes possessed 2-fold higher net Na+ efflux capacity in the root elongation zone. Interestingly, this efflux was only partially mediated by the plasma membrane Na+/H+ antiporter (OsSOS1), suggesting involvement of some other exclusion mechanisms. No significant difference in Na+ exclusion from the mature root zones was found between cultivars, and the transcriptional changes in the salt overly sensitive signaling pathway genes in the elongation zone were not correlated with the genetic variability in salinity tolerance amongst genotypes. The most important hallmark of differential salinity tolerance was in the ability of the plant to retain K+ in both root zones. This trait was conferred by at least three complementary mechanisms: (1) its superior ability to activate H+-ATPase pump operation, both at transcriptional and functional levels; (2) reduced sensitivity of K+ efflux channels to reactive oxygen species; and (3) smaller upregulation in OsGORK and higher upregulation of OsAKT1 in tolerant cultivars in response to salt stress. These traits should be targeted in breeding programs aimed to improve salinity tolerance in commercial rice cultivars.
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Affiliation(s)
- Juan Liu
- Collaborative Innovation Center of Henan Grain Crops, Henan Key Laboratory of Rice Biology, Henan Agricultural University, Zhengzhou, China
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
- *Correspondence: Sergey Shabala, ; Quanzhi Zhao,
| | - Lana Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Holger Meinke
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Gayatri Venkataraman
- Plant Molecular Biology Laboratory, M.S. Swaminathan Research Foundation, Chennai, India
| | - Zhonghua Chen
- School of Science and Health, Western Sydney University, Penrith, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Fanrong Zeng
- Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Quanzhi Zhao
- Collaborative Innovation Center of Henan Grain Crops, Henan Key Laboratory of Rice Biology, Henan Agricultural University, Zhengzhou, China
- *Correspondence: Sergey Shabala, ; Quanzhi Zhao,
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29
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Zeng F, Shabala S, Maksimović JD, Maksimović V, Bonales-Alatorre E, Shabala L, Yu M, Zhang G, Živanović BD. Revealing mechanisms of salinity tissue tolerance in succulent halophytes: A case study for Carpobrotus rossi. PLANT, CELL & ENVIRONMENT 2018; 41:2654-2667. [PMID: 29956332 DOI: 10.1111/pce.13391] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Efforts to breed salt tolerant crops could benefit from investigating previously unexplored traits. One of them is a tissue succulency. In this work, we have undertaken an electrophysiological and biochemical comparison of properties of mesophyll and storage parenchyma leaf tissues of a succulent halophyte species Carpobrotus rosii ("pigface"). We show that storage parenchyma cells of C. rossii act as Na+ sink and possessed both higher Na+ sequestration (298 vs. 215 mM NaCl in mesophyll) and better K+ retention ability. The latter traits was determined by the higher rate of H+ -ATPase operation and higher nonenzymatic antioxidant activity in this tissue. Na+ uptake in both tissues was insensitive to either Gd3+ or elevated Ca2+ ruling out involvement of nonselective cation channels as a major path for Na+ entry. Patch-clamp experiments have revealed that Caprobrotus plants were capable to downregulate activity of fast vacuolar channels when exposed to saline environment; this ability was higher in the storage parenchyma cells compared with mesophyll. Also, storage parenchyma cells have constitutively lower number of open slow vacuolar channels, whereas in mesophyll, this suppression was inducible by salt. Taken together, these results provide a mechanistic basis for efficient Na+ sequestration in the succulent leaf tissues.
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Affiliation(s)
- Fanrong Zeng
- Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
| | - Sergey Shabala
- Department of Horticulture, Foshan University, Foshan, China
- College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
| | | | - Vuk Maksimović
- Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia
| | - Edgar Bonales-Alatorre
- College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
- Centro Universitario de Investigaciones Biomédicas, University of Colima, Colima, México
| | - Lana Shabala
- College of Science and Engineering, University of Tasmania, Hobart, TAS, Australia
| | - Min Yu
- Department of Horticulture, Foshan University, Foshan, China
| | - Guoping Zhang
- Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Branka D Živanović
- Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia
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30
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Pottosin I, Zepeda-Jazo I, Bose J, Shabala S. An Anion Conductance, the Essential Component of the Hydroxyl-Radical-Induced Ion Current in Plant Roots. Int J Mol Sci 2018; 19:E897. [PMID: 29562632 PMCID: PMC5877758 DOI: 10.3390/ijms19030897] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 03/16/2018] [Accepted: 03/16/2018] [Indexed: 01/21/2023] Open
Abstract
Oxidative stress signaling is essential for plant adaptation to hostile environments. Previous studies revealed the essentiality of hydroxyl radicals (HO•)-induced activation of massive K⁺ efflux and a smaller Ca2+ influx as an important component of plant adaptation to a broad range of abiotic stresses. Such activation would modify membrane potential making it more negative. Contrary to these expectations, here, we provide experimental evidence that HO• induces a strong depolarization, from -130 to -70 mV, which could only be explained by a substantial HO•-induced efflux of intracellular anions. Application of Gd3+ and NPPB, non-specific blockers of cation and anion conductance, respectively, reduced HO•-induced ion fluxes instantaneously, implying a direct block of the dual conductance. The selectivity of an early instantaneous HO•-induced whole cell current fluctuated from more anionic to more cationic and vice versa, developing a higher cation selectivity at later times. The parallel electroneutral efflux of K⁺ and anions should underlie a substantial leak of the cellular electrolyte, which may affect the cell's turgor and metabolic status. The physiological implications of these findings are discussed in the context of cell fate determination, and ROS and cytosolic K⁺ signaling.
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Affiliation(s)
- Igor Pottosin
- Centro Universitario de Investigaciones Biomédicas, Universidad de Colima; Av. 25 de julio 965, Villa de San Sebastian, Colima, Col. 28045, Mexico.
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas. 7001, Australia.
| | - Isaac Zepeda-Jazo
- Genómica Alimentaria, Universidad de La Ciénega del Estado de Michoacán de Ocampo, Av. Universidad 3000, Lomas de la Universidad, Sahuayo, Mich. 59103, Mexico.
| | - Jayakumar Bose
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, University of Adelaide, Adelaide SA 5064, Australia.
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas. 7001, Australia.
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31
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Wang H, Shabala L, Zhou M, Shabala S. Hydrogen Peroxide-Induced Root Ca 2+ and K⁺ Fluxes Correlate with Salt Tolerance in Cereals: Towards the Cell-Based Phenotyping. Int J Mol Sci 2018; 19:E702. [PMID: 29494514 PMCID: PMC5877563 DOI: 10.3390/ijms19030702] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 02/16/2018] [Accepted: 02/22/2018] [Indexed: 12/25/2022] Open
Abstract
Salinity stress-induced production of reactive oxygen species (ROS) and associated oxidative damage is one of the major factors limiting crop production in saline soils. However, the causal link between ROS production and stress tolerance is not as straightforward as one may expect, as ROS may also play an important signaling role in plant adaptive responses. In this study, the causal relationship between salinity and oxidative stress tolerance in two cereal crops-barley (Hordeum vulgare) and wheat (Triticum aestivum)-was investigated by measuring the magnitude of ROS-induced net K⁺ and Ca2+ fluxes from various root tissues and correlating them with overall whole-plant responses to salinity. We have found that the association between flux responses to oxidative stress and salinity stress tolerance was highly tissue specific, and was also dependent on the type of ROS applied. No correlation was found between root responses to hydroxyl radicals and the salinity tolerance. However, when oxidative stress was administered via H₂O₂ treatment, a significant positive correlation was found for the magnitude of ROS-induced K⁺ efflux and Ca2+ uptake in barley and the overall salinity stress tolerance, but only for mature zone and not the root apex. The same trends were found for wheat. These results indicate high tissue specificity of root ion fluxes response to ROS and suggest that measuring the magnitude of H₂O₂-induced net K⁺ and Ca2+ fluxes from mature root zone may be used as a tool for cell-based phenotyping in breeding programs aimed to improve salinity stress tolerance in cereals.
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Affiliation(s)
- Haiyang Wang
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia.
| | - Lana Shabala
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia.
| | - Meixue Zhou
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia.
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia.
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32
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Farhangi-Abriz S, Nikpour-Rashidabad N. Effect of lignite on alleviation of salt toxicity in soybean (Glycine max L.) plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 120:186-193. [PMID: 29035772 DOI: 10.1016/j.plaphy.2017.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 10/08/2017] [Accepted: 10/09/2017] [Indexed: 06/07/2023]
Abstract
Salt toxicity of agricultural land is a natural phenomenon which is due to agricultural irrigation. This toxicity is harmful to crop productivity via increasing oxidative stress products. In a factorial controlled trial, four levels of lignite-enriched soil (soil lignite content: none, 50, 75 and 100 g kg-1) were exposed to three levels of soil salinity (0, 5 and 10 dS m-1 NaCl). Then reactive oxygen species (ROS) generation (hydrogen peroxide and superoxide radical), lipid peroxidation, antioxidant enzymes activities (peroxidase, catalase and super oxide dismutase), proline, glycine betaine, soluble sugars and soluble protein contents of soybean plants were compared across different lignite concentration and saline toxicity. Under the 5 and 10 dS m-1 NaCl, sodium entry to the leaf and root cells, hydrogen peroxide concentration, superoxide radical generation, lipid peroxidation and osmoprotectants creation increased and consequently plant growth reduced (12-49%). Lignite applications by improving the cation exchange capacity of soil (8-16%), enriched the leaf and root cells with potassium (5-26%), calcium (40-56%), magnesium (30-42%) and inhibited the sodium entry to the cells, and consequently increased potassium/sodium ratio and reduced oxidative stress, antioxidant activities and synthesis of osmoprotectants in soybean leading to increased plant biomass (18-37%). Lignite usage in 75 and 100 g kg-1 soil showed a better effect than 50 g kg-1 soil on reducing harmful effects of salt toxicity. Soil enrichment with lignite improves plant tolerance to salt toxicity via decreased oxidative stress.
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Affiliation(s)
- Salar Farhangi-Abriz
- Department of Plant Eco-physiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
| | - Neda Nikpour-Rashidabad
- Department of Plant Eco-physiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
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Wang N, Qiao W, Liu X, Shi J, Xu Q, Zhou H, Yan G, Huang Q. Relative contribution of Na +/K + homeostasis, photochemical efficiency and antioxidant defense system to differential salt tolerance in cotton (Gossypium hirsutum L.) cultivars. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 119:121-131. [PMID: 28866234 DOI: 10.1016/j.plaphy.2017.08.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 08/25/2017] [Accepted: 08/28/2017] [Indexed: 05/15/2023]
Abstract
In this study, the role of specific components of different coping strategies to salt load were identified. A pot experiment was conducted with four cotton (Gossypium hirsutum L.) cultivars (differing in salt-sensitivity) under salinity stress. Based on observed responses in growth performance and physiological characteristics, CZ91 was the most tolerant of the four cultivars, followed by cultivars CCRI44 and CCRI49, with Z571 being much more sensitive to salt stress. To perform this tolerant response, they implement different adaptative mechanisms to cope with salt-stress. The superior salt tolerance of CZ91 was conferred by at least three complementary physiological mechanisms: its ability to regulate K+ and Na+ transport more effectively, its higher photochemical efficiency and better antioxidant defense capacity. However, only one or a few specific components of these defense systems play crucial roles in moderately salt tolerant CCRI44 and CCRI49. Lower ROS load in CCRI44 may be attributed to simultaneous induction of antioxidant defenses by maintaining an unusually high level of SOD, and higher activities of CAT, APX, and POD during salt stress. CCRI49 could reduce the excess generation of ROS not only by maintaining a higher selective absorption of K+ over Na+ in roots across the membranes through SOS1, AKT1, and HAK5, but also by displaying higher excess-energy dissipation (e.g., higher ETR, PR and qN) during salt stress. Overall, our data provide a mechanistic explanation for differential salt stress tolerance among these cultivars and shed light on the different strategies employed by cotton cultivars to minimize the ill effects of stress.
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Affiliation(s)
- Ning Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China
| | - Wenqing Qiao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China
| | - Xiaohong Liu
- Scientific Research Department, Xinjiang Qianhai Seeds Co., Ltd., Tumushuke 843900, PR China
| | - Jianbin Shi
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China
| | - Qinghua Xu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China
| | - Hong Zhou
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China
| | - Gentu Yan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China.
| | - Qun Huang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455000, PR China.
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Kiani-Pouya A, Roessner U, Jayasinghe NS, Lutz A, Rupasinghe T, Bazihizina N, Bohm J, Alharbi S, Hedrich R, Shabala S. Epidermal bladder cells confer salinity stress tolerance in the halophyte quinoa and Atriplex species. PLANT, CELL & ENVIRONMENT 2017; 40:1900-1915. [PMID: 28558173 DOI: 10.1111/pce.12995] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 05/21/2017] [Indexed: 05/02/2023]
Abstract
Epidermal bladder cells (EBCs) have been postulated to assist halophytes in coping with saline environments. However, little direct supporting evidence is available. Here, Chenopodium quinoa plants were grown under saline conditions for 5 weeks. One day prior to salinity treatment, EBCs from all leaves and petioles were gently removed by using a soft cosmetic brush and physiological, ionic and metabolic changes in brushed and non-brushed leaves were compared. Gentle removal of EBC neither initiated wound metabolism nor affected the physiology and biochemistry of control-grown plants but did have a pronounced effect on salt-grown plants, resulting in a salt-sensitive phenotype. Of 91 detected metabolites, more than half were significantly affected by salinity. Removal of EBC dramatically modified these metabolic changes, with the biggest differences reported for gamma-aminobutyric acid (GABA), proline, sucrose and inositol, affecting ion transport across cellular membranes (as shown in electrophysiological experiments). This work provides the first direct evidence for a role of EBC in salt tolerance in halophytes and attributes this to (1) a key role of EBC as a salt dump for external sequestration of sodium; (2) improved K+ retention in leaf mesophyll and (3) EBC as a storage space for several metabolites known to modulate plant ionic relations.
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Affiliation(s)
- Ali Kiani-Pouya
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
| | - Ute Roessner
- School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Nirupama S Jayasinghe
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Adrian Lutz
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Thusitha Rupasinghe
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Nadia Bazihizina
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
- Deptartment of Agrifood Production and Environmental Science, University of Florence, I-50019, Florence, Italy
| | - Jennifer Bohm
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, Würzburg University, 97082, Wurzburg, Germany
| | - Sulaiman Alharbi
- Zoology Department, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, Würzburg University, 97082, Wurzburg, Germany
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
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Assaha DVM, Ueda A, Saneoka H, Al-Yahyai R, Yaish MW. The Role of Na + and K + Transporters in Salt Stress Adaptation in Glycophytes. Front Physiol 2017; 8:509. [PMID: 28769821 PMCID: PMC5513949 DOI: 10.3389/fphys.2017.00509] [Citation(s) in RCA: 338] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 07/03/2017] [Indexed: 12/30/2022] Open
Abstract
Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.
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Affiliation(s)
- Dekoum V. M. Assaha
- Department of Biology, College of Science, Sultan Qaboos UniversityMuscat, Oman
| | - Akihiro Ueda
- Graduate School of Biosphere Science, Hiroshima UniversityHiroshima, Japan
| | - Hirofumi Saneoka
- Graduate School of Biosphere Science, Hiroshima UniversityHiroshima, Japan
| | - Rashid Al-Yahyai
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos UniversityMuscat, Oman
| | - Mahmoud W. Yaish
- Department of Biology, College of Science, Sultan Qaboos UniversityMuscat, Oman
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Bose J, Munns R, Shabala S, Gilliham M, Pogson B, Tyerman SD. Chloroplast function and ion regulation in plants growing on saline soils: lessons from halophytes. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3129-3143. [PMID: 28472512 DOI: 10.1093/jxb/erx142] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Salt stress impacts multiple aspects of plant metabolism and physiology. For instance it inhibits photosynthesis through stomatal limitation, causes excessive accumulation of sodium and chloride in chloroplasts, and disturbs chloroplast potassium homeostasis. Most research on salt stress has focused primarily on cytosolic ion homeostasis with few studies of how salt stress affects chloroplast ion homeostasis. This review asks the question whether membrane-transport processes and ionic relations are differentially regulated between glycophyte and halophyte chloroplasts and whether this contributes to the superior salt tolerance of halophytes. The available literature indicates that halophytes can overcome stomatal limitation by switching to CO2 concentrating mechanisms and increasing the number of chloroplasts per cell under saline conditions. Furthermore, salt entry into the chloroplast stroma may be critical for grana formation and photosystem II activity in halophytes but not in glycophytes. Salt also inhibits some stromal enzymes (e.g. fructose-1,6-bisphosphatase) to a lesser extent in halophyte species. Halophytes accumulate more chloride in chloroplasts than glycophytes and appear to use sodium in functional roles. We propose the molecular identities of candidate transporters that move sodium, chloride and potassium across chloroplast membranes and discuss how their operation may regulate photochemistry and photosystem I and II activity in chloroplasts.
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Affiliation(s)
- Jayakumar Bose
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia
| | - Rana Munns
- Australian Research Council Centre of Excellence in Plant Energy Biology, and School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, TAS 7001, Australia
| | - Matthew Gilliham
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia
| | - Barry Pogson
- Australian Research Council Centre of Excellence in Plant Energy Biology, Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Stephen D Tyerman
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia
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Miranda RDS, Mesquita RO, Costa JH, Alvarez-Pizarro JC, Prisco JT, Gomes-Filho E. Integrative Control Between Proton Pumps and SOS1 Antiporters in Roots is Crucial for Maintaining Low Na+ Accumulation and Salt Tolerance in Ammonium-Supplied Sorghum bicolor. PLANT & CELL PHYSIOLOGY 2017; 58:522-536. [PMID: 28158828 DOI: 10.1093/pcp/pcw231] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/23/2016] [Indexed: 05/28/2023]
Abstract
An effective strategy for re-establishing K+ and Na+ homeostasis is a challenge for the improvement of plant performance in saline soil. Specifically, attempts to understand the mechanisms of Na+ extrusion from plant cells, the control of Na+ loading in the xylem and the partitioning of the accumulated Na+ between different plant organs are ongoing. Our goal was to provide insight into how an external nitrogen source affects Na+ accumulation in Sorghum bicolor under saline conditions. The NH4+ supply improved the salt tolerance of the plant by restricting Na+ accumulation and improving the K+/Na+ homeostasis in shoots, which was consistent with the high activity and expression of Na+/H+ antiporters and proton pumps in the plasma membrane and vacuoles in the roots, resulting in low Na+ loading in the xylem. Conversely, although NO3--grown plants had exclusion and sequestration mechanisms for Na+, these responses were not sufficient to reduce Na+ accumulation. In conclusion, NH4+ acts as an efficient signal to activate co-ordinately responses involved in the regulation of Na+ homeostasis in sorghum plants under salt stress, which leads to salt tolerance.
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Affiliation(s)
- Rafael de Souza Miranda
- Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal/CNPq), Universidade Federal do Ceará, 60440-554, Fortaleza, Ceará, Brazil
| | | | - José Hélio Costa
- Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal/CNPq), Universidade Federal do Ceará, 60440-554, Fortaleza, Ceará, Brazil
| | - Juan Carlos Alvarez-Pizarro
- Centro de Ciências Agrárias e da Biodiversidade, Universidade Federal do Cariri, 63133-610, Crato, Ceará, Brazil
| | - José Tarquinio Prisco
- Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal/CNPq), Universidade Federal do Ceará, 60440-554, Fortaleza, Ceará, Brazil
| | - Enéas Gomes-Filho
- Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal/CNPq), Universidade Federal do Ceará, 60440-554, Fortaleza, Ceará, Brazil
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38
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Kurniasih B, Greenway H, Colmer TD. Energetics of acclimation to NaCl by submerged, anoxic rice seedlings. ANNALS OF BOTANY 2017; 119:129-142. [PMID: 27694332 PMCID: PMC5218384 DOI: 10.1093/aob/mcw189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 07/12/2016] [Accepted: 08/05/2016] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS Our aim was to elucidate how plant tissues under a severe energy crisis cope with imposition of high NaCl, which greatly increases ion fluxes and hence energy demands. The energy requirements for ion regulation during combined salinity and anoxia were assessed to gain insights into ion transport processes in the anoxia-tolerant coleoptile of rice. METHODS We studied the combined effects of anoxia plus 50 or 100 mm NaCl on tissue ions and growth of submerged rice (Oryza sativa) seedlings. Excised coleoptiles allowed measurements in aerated or anoxic conditions of ion net fluxes and O2 consumption or ethanol formation and by inference energy production. KEY RESULTS Over 80 h of anoxia, coleoptiles of submerged intact seedlings grew at 100 mm NaCl, but excised coleoptiles, with 50 mm exogenous glucose, survived only at 50 mm NaCl, possibly due to lower energy production with glucose than for intact coleoptiles with sucrose as substrate. Rates of net uptake of Na+ and Cl- by coleoptiles in anoxia were about half those in aerated solution. Ethanol formation in anoxia and O2 uptake in aerobic solution were each increased by 13-15 % at 50 mm NaCl, i.e. ATP formation was stimulated. For acclimation to 50 mm NaCl, the anoxic tissues used only 25 % of the energy that was expended by aerobic tissues. Following return of coleoptiles to aerated non-saline solution, rates of net K+ uptake recovered to those in continuously aerated solution, demonstrating there was little injury during anoxia with 50 mm NaCl. CONCLUSION Rice seedlings survive anoxia, without the coleoptile incurring significant injury, even with the additional energy demands imposed by NaCl (100 mm when intact, 50 mm when excised). Energy savings were achieved in saline anoxia by less coleoptile growth, reduced ion fluxes as compared to aerobic coleoptiles and apparent energy-economic ion transport systems.
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Affiliation(s)
| | | | - Timothy David Colmer
- School of Plant Biology and
- Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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Percey WJ, Shabala L, Wu Q, Su N, Breadmore MC, Guijt RM, Bose J, Shabala S. Potassium retention in leaf mesophyll as an element of salinity tissue tolerance in halophytes. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 109:346-354. [PMID: 27810674 DOI: 10.1016/j.plaphy.2016.10.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/11/2016] [Accepted: 10/12/2016] [Indexed: 05/22/2023]
Abstract
Soil salinity remains a major threat to global food security, and the progress in crop breeding for salinity stress tolerance may be achieved only by pyramiding key traits mediating plant adaptive responses to high amounts of dissolved salts in the rhizosphere. This task may be facilitated by studying natural variation in salinity tolerance among plant species and, specifically, exploring mechanisms of salinity tolerance in halophytes. The aim of this work was to establish the causal link between mesophyll ion transport activity and plant salt tolerance in a range of evolutionary contrasting halophyte and glycophyte species. Plants were grown under saline conditions in a glasshouse, followed by assessing their growth and photosynthetic performance. In a parallel set of experiments, net K+ and H+ transport across leaf mesophyll and their modulation by light were studied in control and salt-treated mesophyll segments using vibrating non-invasive ion selective microelectrode (the MIFE) technique. The reported results show that mesophyll cells in glycophyte species loses 2-6 fold more K+ compared with their halophyte counterparts. This decline was reflected in a reduced maximum photochemical efficiency of photosystem II, chlorophyll content and growth observed in the glasshouse experiments. In addition to reduced K+ efflux, the more tolerant species also exhibited reduced H+ efflux, which is interpreted as an energy-saving strategy allowing more resources to be redirected towards plant growth. It is concluded that the ability of mesophyll to retain K+ without a need to activate plasma membrane H+-ATPase is an essential component of salinity tolerance in halophytes and halophytic crop plants.
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Affiliation(s)
- William J Percey
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia
| | - Lana Shabala
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia
| | - Qi Wu
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia; College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Nana Su
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia; College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Michael C Breadmore
- Australian Centre for Research on Separation Science (ACROSS), School of Chemistry, University of Tasmania, Hobart, Tas 7001, Australia
| | - Rosanne M Guijt
- School of Pharmacy, University of Tasmania, Hobart, Tas 7001, Australia
| | - Jayakumar Bose
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Hobart, Tas 7001, Australia.
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40
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Bojórquez-Quintal E, Ruiz-Lau N, Velarde-Buendía A, Echevarría-Machado I, Pottosin I, Martínez-Estévez M. Natural variation in primary root growth and K + retention in roots of habanero pepper (Capsicum chinense) under salt stress. FUNCTIONAL PLANT BIOLOGY : FPB 2016; 43:1114-1125. [PMID: 32480531 DOI: 10.1071/fp15391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Accepted: 07/24/2016] [Indexed: 06/11/2023]
Abstract
In this work, we analysed the natural variation in mechanisms for protection against salt stress in pepper varieties (Capsicum chinense Jacq. cv. Rex, Chichen-Itza and Naranja and Capsicum annuum L. cv. Padron), considering primary root growth and viability of the post-stressed seedlings. NaCl-induced K+ and H+ efflux in roots was also studied by ion-selective microelectrodes under application of pharmacological agents. In these pepper varieties, the magnitude of the K+ leakage in the roots positively correlated with growth inhibition of the primary root in the presence of NaCl, with Rex variety showing a higher level of tolerance than Chichen-Itza. The K+ leakage and the activity of the H+ pump in the roots were dependent on the NaCl concentration. Pharmacological analysis indicated that the NaCl-induced K+ leakage was mediated by TEA+-sensitive KOR channels but not by NSCC channels. In addition, we present evidence for the possible participation of proline, and a Na+-insensitive HAK K+ transporter expressed in habanero pepper roots for maintaining K+ homeostasis under salt stress conditions.
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Affiliation(s)
- Emanuel Bojórquez-Quintal
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Yucatán, México
| | - Nancy Ruiz-Lau
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Yucatán, México
| | - Ana Velarde-Buendía
- Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Colima, México
| | - Ileana Echevarría-Machado
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Yucatán, México
| | - Igor Pottosin
- Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Colima, México
| | - Manuel Martínez-Estévez
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Yucatán, México
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Percey WJ, McMinn A, Bose J, Breadmore MC, Guijt RM, Shabala S. Salinity effects on chloroplast PSII performance in glycophytes and halophytes. FUNCTIONAL PLANT BIOLOGY : FPB 2016; 43:1003-1015. [PMID: 32480522 DOI: 10.1071/fp16135] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 06/12/2016] [Indexed: 06/11/2023]
Abstract
The effects of NaCl stress and K+ nutrition on photosynthetic parameters of isolated chloroplasts were investigated using PAM fluorescence. Intact mesophyll cells were able to maintain optimal photosynthetic performance when exposed to salinity for more than 24h whereas isolated chloroplasts showed declines in both the relative electron transport rate (rETR) and the maximal photochemical efficiency of PSII (Fv/Fm) within the first hour of treatment. The rETR was much more sensitive to salt stress compared with Fv/Fm, with 40% inhibition of rETR observed at apoplastic NaCl concentration as low as 20mM. In isolated chloroplasts, absolute K+ concentrations were more essential for the maintenance of the optimal photochemical performance (Fv/Fm values) rather than sodium concentrations per se. Chloroplasts from halophyte species of quinoa (Chenopodium quinoa Willd.) and pigface (Carpobrotus rosii (Haw.) Schwantes) showed less than 18% decline in Fv/Fm under salinity, whereas the Fv/Fm decline in chloroplasts from glycophyte pea (Pisum sativum L.) and bean (Vicia faba L.) species was much stronger (31 and 47% respectively). Vanadate (a P-type ATPase inhibitor) significantly reduced Fv/Fm in both control and salinity treated chloroplasts (by 7 and 25% respectively), whereas no significant effects of gadolinium (blocker of non-selective cation channels) were observed in salt-treated chloroplasts. Tetraethyl ammonium (TEA) (K+ channel inhibitor) and amiloride (inhibitor of the Na+/H+ antiporter) increased the Fv/Fm of salinity treated chloroplasts by 16 and 17% respectively. These results suggest that chloroplasts' ability to regulate ion transport across the envelope and thylakoid membranes play a critical role in leaf photosynthetic performance under salinity.
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Affiliation(s)
- William J Percey
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart 7001, Australia
| | - Andrew McMinn
- Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart 7001, Australia
| | - Jayakumar Bose
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart 7001, Australia
| | - Michael C Breadmore
- Australian Centre for Research on Separation Science (ACROSS) and School of Chemistry, University of Tasmania, Private Bag 75, Hobart 7001, Australia
| | - Rosanne M Guijt
- School of Medicine and Australian Centre for Research on Separation Science, University of Tasmania, Private Bag 34, Hobart 7001, Australia
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart 7001, Australia
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42
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Wang CM, Xia ZR, Wu GQ, Yuan HJ, Wang XR, Li JH, Tian FP, Zhang Q, Zhu XQ, He JJ, Kumar T, Wang XL, Zhang JL. The coordinated regulation of Na + and K + in Hordeum brevisubulatum responding to time of salt stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 252:358-366. [PMID: 27717472 DOI: 10.1016/j.plantsci.2016.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/10/2016] [Accepted: 08/13/2016] [Indexed: 05/20/2023]
Abstract
Hordeum brevisubulatum, called as wild barley, is a useful monocotyledonous halophyte for soil improvement in northern China. Although previously studied, its main salt tolerance mechanism remained controversial. The current work showed that shoot Na+ concentration was increased rapidly with stress time and significantly higher than in wheat during 0-168h of 100mM NaCl treatment. Similar results were also found under 25 and 50mM NaCl treatments. Even K+ was increased from 0.01 to 50mM in the cultural solution, no significant effect was found on tissue Na+ concentrations. Interestingly, shoot growth was improved, and stronger root activity was maintained in H. brevisubulatum compared with wheat after 7days treatment of 100mM NaCl. To investigate the long-term stress impact on tissue Na+, 100mM NaCl was prolonged to 60 days. The maximum values of Na+ concentrations were observed at 7th in shoot and 14th day in roots, respectively, and then decreased gradually. Micro-electrode ion flux estimation was used and it was found that increasing Na+ efflux while maintaining K+ influx were the major strategies to reduce the Na+ concentration during long-term salt stress. Moreover, leaf Na+ secretions showed little contribution to the tissue Na+ decrease. Thereby, the physiological mechanism for H. brevisubulatum to survive from long-term salt stress was proposed that rapid Na+ accumulation occurred in the shoot to respond the initial salt shock, then Na+ efflux was triggered and K+ influx was activated to maintain a stable K+/Na+ ratio in tissues.
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Affiliation(s)
- Chun-Mei Wang
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Zeng-Run Xia
- State Key Laboratory of Grassland Agro-ecosystem, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, People's Republic of China
| | - Guo-Qiang Wu
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
| | - Hui-Jun Yuan
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
| | - Xin-Rui Wang
- College of Animal Science, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Jin-Hua Li
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Fu-Ping Tian
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Qian Zhang
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Xin-Qiang Zhu
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Jiong-Jie He
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China
| | - Tanweer Kumar
- State Key Laboratory of Grassland Agro-ecosystem, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, People's Republic of China
| | - Xiao-Li Wang
- Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, People's Republic of China.
| | - Jin-Lin Zhang
- State Key Laboratory of Grassland Agro-ecosystem, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, People's Republic of China.
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Lee SJ, Jeong EM, Ki AY, Oh KS, Kwon J, Jeong JH, Chung NJ. Oxidative defense metabolites induced by salinity stress in roots of Salicornia herbacea. JOURNAL OF PLANT PHYSIOLOGY 2016; 206:133-142. [PMID: 27770750 DOI: 10.1016/j.jplph.2016.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/28/2016] [Accepted: 08/28/2016] [Indexed: 05/21/2023]
Abstract
High salinity is a major abiotic stress that affects the growth and development of plants. This type of stress can influence flowering, the production of crops, defense mechanisms and other physiological processes. Previous studies have attempted to elucidate salt-tolerance mechanisms to improve plant growth and productivity in the presence of sodium chloride. One such plant that has been studied in detail is Salicornia, a well-known halophyte, which has adapted to grow in the presence of high salt. To further the understanding of how Salicornia grows and develops under high saline conditions, Salicornia herbacea (S. herbacea) was grown under varying saline concentrations (0, 50, 100, 200, 300, and 400mM), and the resulting phenotype, ion levels, and metabolites were investigated. The optimal condition for the growth of S. herbacea was determined to be 100mM NaCl, and increased salt concentrations directly decreased the internal concentrations of other inorganic ions including Ca2+, K+, and Mg2+. Metabolomics were performed on the roots of the plant as a systematic metabolomics study has not yet been reported for Salicornia roots. Using ethylacetate and methanol extraction followed by high resolution ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), 1793 metabolites were identified at different NaCl levels. Structural and functional analyses demonstrated that the concentration of 53 metabolites increased as the concentration of NaCl increased. These metabolites have been linked to stress responses, primarily oxidative stress responses, which increase under saline stress. Most metabolites can be classified as polyols, alkaloids, and steroids. Functional studies of these metabolites show that shikimic acid, vitamin K1, and indole-3-carboxylic acid are generated as a result of defense mechanisms, including the shikimate pathway, to protect against reactive oxygen species (ROS) generated by salt stress. This metabolite profiling provides valuable information on the salt-tolerance mechanisms of S. herbacea and may be applied to bioengineer plants with improved salt tolerance.
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Affiliation(s)
- Seung Jae Lee
- Department of Chemistry and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 54896, Republic of Korea
| | - Eun-Mi Jeong
- Department of Chemistry and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 54896, Republic of Korea
| | - Ah Young Ki
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Republic of Korea; Biological Disaster Analysis Group, Korea Basic Science Institute, Daejeon 34133, Republic of Korea
| | - Kyung-Seo Oh
- Biological Disaster Analysis Group, Korea Basic Science Institute, Daejeon 34133, Republic of Korea
| | - Joseph Kwon
- Biological Disaster Analysis Group, Korea Basic Science Institute, Daejeon 34133, Republic of Korea
| | - Jae-Hyuk Jeong
- Crop Production and Physiology Division, National Institute of Crop Science, Jeonju 54875, Republic of Korea
| | - Nam-Jin Chung
- Department of Crop Science and Biotechnology, Chonbuk National University, Jeonju 54896, Republic of Korea.
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Chakraborty K, Bose J, Shabala L, Eyles A, Shabala S. Evaluating relative contribution of osmotolerance and tissue tolerance mechanisms toward salinity stress tolerance in three Brassica species. PHYSIOLOGIA PLANTARUM 2016; 158:135-51. [PMID: 27062083 DOI: 10.1111/ppl.12447] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 02/15/2016] [Accepted: 02/22/2016] [Indexed: 05/20/2023]
Abstract
Three different species of Brassica, with differential salt sensitivity were used to understand physiological mechanisms of salt tolerance operating in these species and to evaluate the relative contribution of different strategies to cope with salt load. Brassica napus was the most tolerant species in terms of the overall performance, with Brassica juncea and Brassica oleracea being much more sensitive to salt stress with no obvious difference between them. While prominent reduction in net CO2 assimilation was observed in both sensitive species, physiological mechanisms beyond this reduction differed strongly. Brassica juncea plants possessed high osmotolerance and were able to maintain high transpiration rate but showed a significant reduction in leaf chlorophyll content and efficiency of leaf photochemistry. On the contrary, B. oleracea plants possessed the highest (among the three species) tissue tolerance but showed a very significant stomatal limitation of photosynthesis. Electrophysiological experiments revealed that the high tissue tolerance in B. oleracea was related to the ability of leaf mesophyll cells to maintain highly negative membrane potential in the presence of high apoplastic Na(+) . In addition to high osmotolerance, the most tolerant B. napus showed also lesser accumulation of toxic Na(+) and Cl(-) in the leaf, possessed moderate tissue tolerance and had a superior K(+) retention ability. Taken together, the results from this study indicate that the three Brassica species employ very different mechanisms to cope with salinity and, despite its overall sensitivity to salinity, B. oleracea could be recommended as a valuable 'donor' of tissue tolerance genes to confer this trait for marker-assisted breeding programs.
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Affiliation(s)
- Koushik Chakraborty
- Department of Plant Physiology, ICAR-Directorate of Groundnut Research, Junagadh 362 001, India
- School of Land and Food and Tasmanian Institute of Agriculture, University of Tasmania, Hobart 7001, Australia
| | - Jayakumar Bose
- School of Land and Food and Tasmanian Institute of Agriculture, University of Tasmania, Hobart 7001, Australia
| | - Lana Shabala
- School of Land and Food and Tasmanian Institute of Agriculture, University of Tasmania, Hobart 7001, Australia
| | - Alieta Eyles
- School of Land and Food and Tasmanian Institute of Agriculture, University of Tasmania, Hobart 7001, Australia
| | - Sergey Shabala
- School of Land and Food and Tasmanian Institute of Agriculture, University of Tasmania, Hobart 7001, Australia.
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Pandolfi C, Azzarello E, Mancuso S, Shabala S. Acclimation improves salt stress tolerance in Zea mays plants. JOURNAL OF PLANT PHYSIOLOGY 2016; 201:1-8. [PMID: 27372277 DOI: 10.1016/j.jplph.2016.06.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 06/06/2023]
Abstract
Plants exposure to low level salinity activates an array of processes leading to an improvement of plant stress tolerance. Although the beneficial effect of acclimation was demonstrated in many herbaceous species, underlying mechanisms behind this phenomenon remain poorly understood. In the present study we have addressed this issue by investigating ionic mechanisms underlying the process of plant acclimation to salinity stress in Zea mays. Effect of acclimation were examined in two parallel sets of experiments: a growth experiment for agronomic assessments, sap analysis, stomatal conductance, chlorophyll content, and confocal laser scanning imaging; and a lab experiment for in vivo ion flux measurements from root tissues. Being exposed to salinity, acclimated plants (1) retain more K(+) but accumulate less Na(+) in roots; (2) have better vacuolar Na(+) sequestration ability in leaves and thus are capable of accumulating larger amounts of Na(+) in the shoot without having any detrimental effect on leaf photochemistry; and (3) rely more on Na(+) for osmotic adjustment in the shoot. At the same time, acclimation affect was not related in increased root Na(+) exclusion ability. It appears that even in a such salt-sensitive species as maize, Na(+) exclusion from uptake is of a much less importance compared with the efficient vacuolar Na(+) sequestration in the shoot.
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Affiliation(s)
- Camilla Pandolfi
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas 7001, Australia; Department of Agrifood and Environmental Science, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino, FI, Italy.
| | - Elisa Azzarello
- Department of Agrifood and Environmental Science, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino, FI, Italy
| | - Stefano Mancuso
- Department of Agrifood and Environmental Science, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino, FI, Italy
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas 7001, Australia
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46
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Chakraborty K, Bose J, Shabala L, Shabala S. Difference in root K+ retention ability and reduced sensitivity of K+-permeable channels to reactive oxygen species confer differential salt tolerance in three Brassica species. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:4611-25. [PMID: 27340231 PMCID: PMC4973732 DOI: 10.1093/jxb/erw236] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Brassica species are known to possess significant inter and intraspecies variability in salinity stress tolerance, but the cell-specific mechanisms conferring this difference remain elusive. In this work, the role and relative contribution of several key plasma membrane transporters to salinity stress tolerance were evaluated in three Brassica species (B. napus, B. juncea, and B. oleracea) using a range of electrophysiological assays. Initial root growth assay and viability staining revealed that B. napus was most tolerant amongst the three species, followed by B. juncea and B. oleracea At the mechanistic level, this difference was conferred by at least three complementary physiological mechanisms: (i) higher Na(+) extrusion ability from roots resulting from increased expression and activity of plasma membrane SOS1-like Na(+)/H(+) exchangers; (ii) better root K(+) retention ability resulting from stress-inducible activation of H(+)-ATPase and ability to maintain more negative membrane potential under saline conditions; and (iii) reduced sensitivity of B. napus root K(+)-permeable channels to reactive oxygen species (ROS). The last two mechanisms played the dominant role and conferred most of the differential salt sensitivity between species. Brassica napus plants were also more efficient in preventing the stress-induced increase in GORK transcript levels and up-regulation of expression of AKT1, HAK5, and HKT1 transporter genes. Taken together, our data provide the mechanistic explanation for differential salt stress sensitivity amongst these species and shed light on transcriptional and post-translational regulation of key ion transport systems involved in the maintenance of the root plasma membrane potential and cytosolic K/Na ratio as a key attribute for salt tolerance in Brassica species.
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Affiliation(s)
- Koushik Chakraborty
- Department of Plant Physiology, ICAR-Directorate of Groundnut Research, Junagadh, Gujarat-362 001, India School of Land and Food and Tasmanian Institute for Agriculture, University of Tasmania, Hobart, Private Bag 94, Tas 7001, Australia
| | - Jayakumar Bose
- School of Land and Food and Tasmanian Institute for Agriculture, University of Tasmania, Hobart, Private Bag 94, Tas 7001, Australia
| | - Lana Shabala
- School of Land and Food and Tasmanian Institute for Agriculture, University of Tasmania, Hobart, Private Bag 94, Tas 7001, Australia
| | - Sergey Shabala
- School of Land and Food and Tasmanian Institute for Agriculture, University of Tasmania, Hobart, Private Bag 94, Tas 7001, Australia
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Ruiz-Lau N, Bojórquez-Quintal E, Benito B, Echevarría-Machado I, Sánchez-Cach LA, Medina-Lara MDF, Martínez-Estévez M. Molecular Cloning and Functional Analysis of a Na +-Insensitive K + Transporter of Capsicum chinense Jacq. FRONTIERS IN PLANT SCIENCE 2016; 7:1980. [PMID: 28083010 PMCID: PMC5186809 DOI: 10.3389/fpls.2016.01980] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 12/13/2016] [Indexed: 05/17/2023]
Abstract
High-affinity K+ (HAK) transporters are encoded by a large family of genes and are ubiquitous in the plant kingdom. These HAK-type transporters participate in low- and high-affinity potassium (K+) uptake and are crucial for the maintenance of K+ homeostasis under hostile conditions. In this study, the full-length cDNA of CcHAK1 gene was isolated from roots of the habanero pepper (Capsicum chinense). CcHAK1 expression was positively regulated by K+ starvation in roots and was not inhibited in the presence of NaCl. Phylogenetic analysis placed the CcHAK1 transporter in group I of the HAK K+ transporters, showing that it is closely related to Capsicum annuum CaHAK1 and Solanum lycopersicum LeHAK5. Characterization of the protein in a yeast mutant deficient in high-affinity K+ uptake (WΔ3) suggested that CcHAK1 function is associated with high-affinity K+ uptake, with Km and Vmax for Rb of 50 μM and 0.52 nmol mg-1 min-1, respectively. K+ uptake in yeast expressing the CcHAK1 transporter was inhibited by millimolar concentrations of the cations ammonium ([Formula: see text]) and cesium (Cs+) but not by sodium (Na+). The results presented in this study suggest that the CcHAK1 transporter may contribute to the maintenance of K+ homeostasis in root cells in C. chinense plants undergoing K+-deficiency and salt stress.
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Affiliation(s)
- Nancy Ruiz-Lau
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
- CONACYT, Instituto Tecnológico Nacional de México, Instituto Tecnológico de Tuxtla GutiérrezTuxtla Gutiérrez, Mexico
| | - Emanuel Bojórquez-Quintal
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
- CONACYT, Laboratorio de Análisis y Diagnóstico del Patrimonio, Colegio de MichoacánZamora, Mexico
| | - Begoña Benito
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de MadridMadrid, Spain
| | - Ileana Echevarría-Machado
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
| | - Lucila A. Sánchez-Cach
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
| | - María de Fátima Medina-Lara
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
| | - Manuel Martínez-Estévez
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de YucatánMérida, Mexico
- *Correspondence: Manuel Martínez-Estévez
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Yuan Y, Zhong M, Shu S, Du N, Sun J, Guo S. Proteomic and Physiological Analyses Reveal Putrescine Responses in Roots of Cucumber Stressed by NaCl. FRONTIERS IN PLANT SCIENCE 2016; 7:1035. [PMID: 27471514 PMCID: PMC4945654 DOI: 10.3389/fpls.2016.01035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/01/2016] [Indexed: 05/03/2023]
Abstract
Soil salinity is a major environmental constraint that threatens agricultural productivity. Different strategies have been developed to improve crop salt tolerance, among which the effects of polyamines have been well-reported. To gain a better understanding of the cucumber (Cucumis sativus L.) responses to NaCl and unravel the underlying mechanism of exogenous putrescine (Put) alleviating salt-induced damage, comparative proteomic analysis was conducted on cucumber roots treated with NaCl, and/or Put for 7 days. The results showed that exogenous Put restored the root growth inhibited by NaCl. Sixty-two differentially expressed proteins implicated in various biological processes were successfully identified by MALDI-TOF/TOF MS. The four largest categories included proteins involved in defense response (24.2%), protein metabolism (24.2%), carbohydrate metabolism (19.4%), and amino acid metabolism (14.5%). Exogenous Put up-regulated most identified proteins involved in carbohydrate metabolism, implying an enhancement in energy generation. Proteins involved in defense response and protein metabolism were differently regulated by Put, which indicated the roles of Put in stress resistance and proteome rearrangement. Put also increased the abundance of proteins involved in amino acid metabolism. Meanwhile, physiological analysis showed that Put could further up-regulated the levels of free amino acids in salt stressed-roots. In addition, Put also improved endogenous polyamines contents by regulating the transcription levels of key enzymes in polyamine metabolism. Taken together, these results suggest that Put may alleviate NaCl-induced growth inhibition through degradation of misfolded/damaged proteins, activation of stress defense, and the promotion of carbohydrate metabolism to generate more energy.
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Affiliation(s)
- Yinghui Yuan
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Min Zhong
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Sheng Shu
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Nanshan Du
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Jin Sun
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
- Suqian Academy of Protected Horticulture, Nanjing Agricultural UniversitySuqian, China
| | - Shirong Guo
- Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural UniversityNanjing, China
- Suqian Academy of Protected Horticulture, Nanjing Agricultural UniversitySuqian, China
- *Correspondence: Shirong Guo
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Wu H, Shabala L, Zhou M, Stefano G, Pandolfi C, Mancuso S, Shabala S. Developing and validating a high-throughput assay for salinity tissue tolerance in wheat and barley. PLANTA 2015; 242:847-57. [PMID: 25991439 DOI: 10.1007/s00425-015-2317-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 04/29/2015] [Indexed: 05/07/2023]
Abstract
Leaf tissue tolerance was strongly and positively correlated with overall salt tolerance in barley, but not in wheat where the inability of sensitive varieties to exclude Na(+) is compensated by their better ability to handle Na(+) accumulated in the shoot via tissue tolerance mechanisms. A new high-throughput assay was developed to use the excised leaves to eliminate the confounding contribution of sodium exclusion mechanisms and evaluate genetic variability in salinity tissue tolerance in a large number of wheat (Triticum aestivum and Triticum turgidum ssp. durum) and barley (Hordeum vulgare) accessions. The changes in relative chlorophyll content (measured as chlorophyll content index, CCI) in excised leaves exposed to 50 mM NaCl for 48 h were found to be a reliable indicator of leaf tissue tolerance. In both wheat and barley, relative CCI correlated strongly with the overall plant salinity tolerance (evaluated in glasshouse experiments). To a large extent, this tissue tolerance was related to more efficient vacuolar Na(+) sequestration in leaf mesophyll, as revealed by fluorescent Na(+) dye imaging experiments. However, while in barley this correlation was positive, tissue tolerance in wheat correlated negatively with overall salinity tolerance. As a result, more salt-sensitive durum wheat genotypes possessed higher tissue tolerance than bread wheat plants, and this negative correlation was present within each of bread and durum wheat clusters as well. Overall, these results indicate that the lack of effective Na(+) exclusion ability in sensitive wheat varieties is compensated by their better ability to handle Na(+) accumulated in the shoot via tissue tolerance mechanisms. Implications of these findings for plant breeding for salinity tolerance are discussed.
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Affiliation(s)
- Honghong Wu
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, TAS, 7001, Australia
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Kumari A, Das P, Parida AK, Agarwal PK. Proteomics, metabolomics, and ionomics perspectives of salinity tolerance in halophytes. FRONTIERS IN PLANT SCIENCE 2015; 6:537. [PMID: 26284080 PMCID: PMC4518276 DOI: 10.3389/fpls.2015.00537] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 07/01/2015] [Indexed: 05/18/2023]
Abstract
Halophytes are plants which naturally survive in saline environment. They account for ∼1% of the total flora of the world. They include both dicots and monocots and are distributed mainly in arid, semi-arid inlands and saline wet lands along the tropical and sub-tropical coasts. Salinity tolerance in halophytes depends on a set of ecological and physiological characteristics that allow them to grow and flourish in high saline conditions. The ability of halophytes to tolerate high salt is determined by the effective coordination between various physiological processes, metabolic pathways and protein or gene networks responsible for delivering salinity tolerance. The salinity responsive proteins belong to diverse functional classes such as photosynthesis, redox homeostasis; stress/defense, carbohydrate and energy metabolism, protein metabolism, signal transduction and membrane transport. The important metabolites which are involved in salt tolerance of halophytes are proline and proline analog (4-hydroxy-N-methyl proline), glycine betaine, pinitol, myo-inositol, mannitol, sorbitol, O-methylmucoinositol, and polyamines. In halophytes, the synthesis of specific proteins and osmotically active metabolites control ion and water flux and support scavenging of oxygen radicals under salt stress condition. The present review summarizes the salt tolerance mechanisms of halophytes by elucidating the recent studies that have focused on proteomic, metabolomic, and ionomic aspects of various halophytes in response to salinity. By integrating the information from halophytes and its comparison with glycophytes could give an overview of salt tolerance mechanisms in halophytes, thus laying down the pavement for development of salt tolerant crop plants through genetic modification and effective breeding strategies.
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Affiliation(s)
- Asha Kumari
- Division of Wasteland Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
- Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
| | - Paromita Das
- Division of Wasteland Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
- Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
| | - Asish Kumar Parida
- Division of Wasteland Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
- Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
| | - Pradeep K. Agarwal
- Division of Wasteland Research, CSIR-Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial ResearchBhavnagar, India
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