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Sena F, Monza J, Signorelli S. Determination of Free Proline in Plants. Methods Mol Biol 2024; 2798:183-194. [PMID: 38587743 DOI: 10.1007/978-1-0716-3826-2_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Proline metabolism has been associated with the induction of reactive oxygen species (ROS), antioxidant enzymes, and the control of cellular redox status. Moreover, proline accumulation is a highly evolutionarily conserved response to diverse abiotic stresses in plants. Thus, proline quantification has been helpful in abiotic stress research as a stress marker. The need for a reliable, fast, and simple method to detect proline in plant tissues is a powerful resource to imply the physiological status of plants under abiotic stress. This chapter summarizes the main strategies for proline extraction and quantification, highlighting their limitations and advantages, and recommends and details a specific protocol for proline extraction and quantification. The chapter provides a friendly version of this protocol with notes useful for researchers to perform the protocol.
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Affiliation(s)
- Florencia Sena
- Food and Plant Biology group, Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Montevideo, Uruguay
- Laboratory of Apicomplexan Biology, Institut Pasteur Montevideo, Montevideo, Uruguay
| | - Jorge Monza
- Food and Plant Biology group, Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Montevideo, Uruguay
| | - Santiago Signorelli
- Food and Plant Biology group, Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Montevideo, Uruguay.
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Crawley, WA, Australia.
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Kumari S, Chhillar H, Chopra P, Khanna RR, Khan MIR. Potassium: A track to develop salinity tolerant plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 167:1011-1023. [PMID: 34598021 DOI: 10.1016/j.plaphy.2021.09.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 09/10/2021] [Accepted: 09/24/2021] [Indexed: 05/24/2023]
Abstract
Salinity is one of the major constraints to plant growth and development across the globe that leads to the huge crop productivity loss. Salinity stress causes impairment in plant's metabolic and cellular processes including disruption in ionic homeostasis due to excess of sodium (Na+) ion influx and potassium (K+) efflux. This condition subsequently results in a significant reduction of the cytosolic K+ levels, eventually inhibiting plant growth attributes. K+ plays a crucial role in alleviating salinity stress by recasting key processes of plants. In addition, K+ acquisition and retention also serve as the perquisite trait to establish salt tolerant mechanism. In addition, an intricate network of genes and their regulatory elements are involved in coordinating salinity stress responses. Furthermore, plant growth regulators (PGRs) and other signalling molecules influence K+-mediated salinity tolerance in plants. Recently, nanoparticles (NPs) have also been found several implications in plants with respect to their roles in mediating K+ homoeostasis during salinity stress in plants. The present review describes salinity-induced adversities in plants and role of K+ in mitigating salinity-induced damages. The review also highlights the efficacy of PGRs and other signalling molecules in regulating K+ mediated salinity tolerance along with nano-technological perspective for improving K+ mediated salinity tolerance in plants.
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Affiliation(s)
- Sarika Kumari
- Department of Botany, Jamia Hamdard, New Delhi-110062, India
| | | | - Priyanka Chopra
- Department of Botany, Jamia Hamdard, New Delhi-110062, India
| | | | - M Iqbal R Khan
- Department of Botany, Jamia Hamdard, New Delhi-110062, India.
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Zhao D, Wang Z, Yang F, Zhu W, An F, Ma H, Tóth T, Liao X, Yang H, Zhang L. Amendments to saline-sodic soils showed long-term effects on improving growth and yield of rice ( Oryza sativa L.). PeerJ 2020; 8:e8726. [PMID: 32195053 PMCID: PMC7069413 DOI: 10.7717/peerj.8726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 02/10/2020] [Indexed: 12/02/2022] Open
Abstract
Background Saline-sodic soils are widely distributed in arid and semi-arid regions around the world. High levels of salt and sodium inhibit the growth and development of crops. However, there has been limited reports on both osmotic potential in soil solutions (OPss) and characteristics of Na+ and K+ absorption in rice in saline-sodic soils under various amendments application. Methods A field experiment was conducted between 2009 and 2017 to analyze the influence of amendments addition to saline-sodic soils on rice growth and yield. Rice was grown in the soil with no amendment (CK), with desulfurization gypsum (DG), with sandy soil (SS), with farmyard manure (FM) and with the mixture of above amendments (M). The osmotic potential in soil solution, selective absorption of K+ over Na+ (SA), selective transport of K+ over Na+ (ST), the distribution of K+ and Na+and yield components in rice plants were investigated. Results The results indicated that amendments application have positive effects on rice yield. The M treatment was the best among the tested amendments with the highest rice grain yield. M treatment increased the OPss values significantly to relieve the inhibition of the water uptake by plants. Additionally, the M treatment significantly enhanced K+ concentration and impeded Na+ accumulation in shoots. SA values were reduced while ST values were increased for all amendments. In conclusion, a mixture of desulfurization gypsum, sandy soil and farmyard manure was the best treatment for the improvement of rice growth and yield in the Songnen Plain, northeast China.
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Affiliation(s)
- Dandan Zhao
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Zhichun Wang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Fan Yang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Wendong Zhu
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Fenghua An
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Hongyuan Ma
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Tibor Tóth
- Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, Budapest, Hungary
| | - Xu Liao
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Hongtao Yang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
| | - Lu Zhang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (CAS), Changchun, China
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Sun Y, Kong X, Li C, Liu Y, Ding Z. Potassium Retention under Salt Stress Is Associated with Natural Variation in Salinity Tolerance among Arabidopsis Accessions. PLoS One 2015; 10:e0124032. [PMID: 25993093 PMCID: PMC4438003 DOI: 10.1371/journal.pone.0124032] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 02/27/2015] [Indexed: 01/09/2023] Open
Abstract
Plants are exposed to various environmental stresses during their life cycle such as salt, drought and cold. Natural variation mediated plant growth adaptation has been employed as an effective approach in response to the diverse environmental cues such as salt stress. However, the molecular mechanism underlying this process is not well understood. In the present study, a collection of 82 Arabidopsis thaliana accessions (ecotypes) was screened with a view to identify variation for salinity tolerance. Seven accessions showed a higher level of tolerance than Col-0. The young seedlings of the tolerant accessions demonstrated a higher K(+) content and a lower Na(+)/K(+) ratio when exposed to salinity stress, but its Na(+) content was the same as that of Col-0. The K(+) transporter genes AtHAK5, AtCHX17 and AtKUP1 were up-regulated significantly in almost all the tolerant accessions, even in the absence of salinity stress. There was little genetic variation or positive transcriptional variation between the selections and Col-0 with respect to Na+-related transporter genes, as AtSOS genes, AtNHX1 and AtHKT1;1. In addition, under salinity stress, these selections accumulated higher compatible solutes and lower reactive oxygen species than did Col-0. Taken together, our results showed that natural variation in salinity tolerance of Arabidopsis seems to have been achieved by the strong capacity of K(+) retention.
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Affiliation(s)
- Yanling Sun
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Xiangpei Kong
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Cuiling Li
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
| | - Yongxiu Liu
- The Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, 100093, Beijing, China
| | - Zhaojun Ding
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, College of Life Sciences, Shandong University, 27 Shanda South Road, Jinan, 250100, Shandong, China
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Yang R, Yang T, Zhang H, Qi Y, Xing Y, Zhang N, Li R, Weeda S, Ren S, Ouyang B, Guo YD. Hormone profiling and transcription analysis reveal a major role of ABA in tomato salt tolerance. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 77:23-34. [PMID: 24531233 DOI: 10.1016/j.plaphy.2014.01.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 01/25/2014] [Indexed: 05/24/2023]
Abstract
The response and adaptation of plants to different environmental stresses are of great interest as they provide the key to understanding the mechanisms underlying stress tolerance. In this study, the changing patterns of four endogenous hormones and various physiological and biochemical parameters of both a salt-tolerant (LA2711) and a salt-sensitive (ZS-5) tomato cultivar were examined under salt stress and non-stress conditions. Additionally, the transcription of key genes in the abscisic acid (ABA) biosynthesis and metabolism were analyzed at different time points. The results indicated that gene expression responsible for ABA biosynthesis and metabolism coincided with the hormone level, and SlNCED1 and SlCYP707A3 may play major roles in the process. LA2711 performed superior to ZS-5 on various parameters, including seed germination, Na(+) compartmentation, selective absorption of K(+), and antioxidant enzymes activity. The difference in salt tolerance between the two genotypes could be attributed to the different levels of ABA due to differences in gene expression of key genes in ABA biosynthesis and metabolism. Although gibberellin, cytokinin and auxin were involved, our results indicated that ABA signaling plays a major role in tomato salt tolerance. As compared to ZS-5, LA2711 had a higher capability to selectively absorb and redistribute K(+) and a higher tolerance to Na(+) in young leaves, which may be the main physiological mechanisms of salt tolerance.
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Affiliation(s)
- Rongchao Yang
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Ting Yang
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Haijun Zhang
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Yan Qi
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Yanxia Xing
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Na Zhang
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Ren Li
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China
| | - Sarah Weeda
- School of Agriculture, Virginia State University, PO Box 9061, Petersburg, VA 23806, USA
| | - Shuxin Ren
- School of Agriculture, Virginia State University, PO Box 9061, Petersburg, VA 23806, USA
| | - Bo Ouyang
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
| | - Yang-Dong Guo
- College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, PR China.
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Singh A, Sarma BK, Upadhyay RS, Singh HB. Compatible rhizosphere microbes mediated alleviation of biotic stress in chickpea through enhanced antioxidant and phenylpropanoid activities. Microbiol Res 2013; 168:33-40. [DOI: 10.1016/j.micres.2012.07.001] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 06/26/2012] [Accepted: 07/07/2012] [Indexed: 11/30/2022]
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Schmidt R, Schippers JH, Welker A, Mieulet D, Guiderdoni E, Mueller-Roeber B. Transcription factor OsHsfC1b regulates salt tolerance and development in Oryza sativa ssp. japonica. AOB PLANTS 2012; 2012:pls011. [PMID: 22616023 PMCID: PMC3357053 DOI: 10.1093/aobpla/pls011] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 04/08/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Salt stress leads to attenuated growth and productivity in rice. Transcription factors like heat shock factors (HSFs) represent central regulators of stress adaptation. Heat shock factors of the classes A and B are well established as regulators of thermal and non-thermal stress responses in plants; however, the role of class C HSFs is unknown. Here we characterized the function of the OsHsfC1b (Os01g53220) transcription factor from rice. METHODOLOGY We analysed the expression of OsHsfC1b in the rice japonica cultivars Dongjin and Nipponbare exposed to salt stress as well as after mannitol, abscisic acid (ABA) and H(2)O(2) treatment. For functional characterization of OsHsfC1b, we analysed the physiological response of a T-DNA insertion line (hsfc1b) and two artificial micro-RNA (amiRNA) knock-down lines to salt, mannitol and ABA treatment. In addition, we quantified the expression of small Heat Shock Protein (sHSP) genes and those related to signalling and ion homeostasis by quantitative real-time polymerase chain reaction in roots exposed to salt. The subcellular localization of OsHsfC1b protein fused to green fluorescent protein (GFP) was determined in Arabidopsis mesophyll cell protoplasts. PRINCIPAL RESULTS Expression of OsHsfC1b was induced by salt, mannitol and ABA, but not by H(2)O(2). Impaired function of OsHsfC1b in the hsfc1b mutant and the amiRNA lines led to decreased salt and osmotic stress tolerance, increased sensitivity to ABA, and temporal misregulation of salt-responsive genes involved in signalling and ion homeostasis. Furthermore, sHSP genes showed enhanced expression in knock-down plants under salt stress. We observed retarded growth of hsfc1b and knock-down lines in comparison with control plants under non-stress conditions. Transient expression of OsHsfC1b fused to GFP in protoplasts revealed nuclear localization of the transcription factor. CONCLUSIONS OsHsfC1b plays a role in ABA-mediated salt stress tolerance in rice. Furthermore, OsHsfC1b is involved in the response to osmotic stress and is required for plant growth under non-stress conditions.
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Affiliation(s)
- Romy Schmidt
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Jos H.M. Schippers
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Annelie Welker
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, Germany
| | - Delphine Mieulet
- CIRAD, UMR AGAP, Avenue Agropolis, 34398 Montpellier, Cedex 5, France
| | | | - Bernd Mueller-Roeber
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, Germany
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
- Corresponding author's e-mail address:
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Atarés A, Moyano E, Morales B, Schleicher P, García-Abellán JO, Antón T, García-Sogo B, Perez-Martin F, Lozano R, Flores FB, Moreno V, del Carmen Bolarin M, Pineda B. An insertional mutagenesis programme with an enhancer trap for the identification and tagging of genes involved in abiotic stress tolerance in the tomato wild-related species Solanum pennellii. PLANT CELL REPORTS 2011; 30:1865-79. [PMID: 21647638 PMCID: PMC3172414 DOI: 10.1007/s00299-011-1094-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 05/14/2011] [Accepted: 05/22/2011] [Indexed: 05/20/2023]
Abstract
Salinity and drought have a huge impact on agriculture since there are few areas free of these abiotic stresses and the problem continues to increase. In tomato, the most important horticultural crop worldwide, there are accessions of wild-related species with a high degree of tolerance to salinity and drought. Thus, the finding of insertional mutants with other tolerance levels could lead to the identification and tagging of key genes responsible for abiotic stress tolerance. To this end, we are performing an insertional mutagenesis programme with an enhancer trap in the tomato wild-related species Solanum pennellii. First, we developed an efficient transformation method which has allowed us to generate more than 2,000 T-DNA lines. Next, the collection of S. pennelli T(0) lines has been screened in saline or drought conditions and several presumptive mutants have been selected for their salt and drought sensitivity. Moreover, T-DNA lines with expression of the reporter uidA gene in specific organs, such as vascular bundles, trichomes and stomata, which may play key roles in processes related to abiotic stress tolerance, have been identified. Finally, the growth of T-DNA lines in control conditions allowed us the identification of different development mutants. Taking into account that progenies from the lines are being obtained and that the collection of T-DNA lines is going to enlarge progressively due to the high transformation efficiency achieved, there are great possibilities for identifying key genes involved in different tolerance mechanisms to salinity and drought.
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Affiliation(s)
- Alejandro Atarés
- Instituto de Biología Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia, CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | - Elena Moyano
- CEBAS-CSIC, Campus de Espinardo, Apdo. 164, 30100 Murcia, Spain
| | - Belén Morales
- CEBAS-CSIC, Campus de Espinardo, Apdo. 164, 30100 Murcia, Spain
| | - Peter Schleicher
- Instituto de Biología Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia, CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | | | - Teresa Antón
- Instituto de Biología Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia, CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | - Begoña García-Sogo
- Instituto de Biología Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia, CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | - Fernando Perez-Martin
- Departamento de Biología Aplicada, E. Politécnica Superior, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
| | - Rafael Lozano
- Departamento de Biología Aplicada, E. Politécnica Superior, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
| | | | - Vicente Moreno
- Instituto de Biología Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia, CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | | | - Benito Pineda
- Departamento de Biología Aplicada, E. Politécnica Superior, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
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Chen H, Lai Z, Shi J, Xiao Y, Chen Z, Xu X. Roles of arabidopsis WRKY18, WRKY40 and WRKY60 transcription factors in plant responses to abscisic acid and abiotic stress. BMC PLANT BIOLOGY 2010; 10:281. [PMID: 21167067 PMCID: PMC3023790 DOI: 10.1186/1471-2229-10-281] [Citation(s) in RCA: 302] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 12/19/2010] [Indexed: 05/17/2023]
Abstract
BACKGROUND WRKY transcription factors are involved in plant responses to both biotic and abiotic stresses. Arabidopsis WRKY18, WRKY40, and WRKY60 transcription factors interact both physically and functionally in plant defense responses. However, their role in plant abiotic stress response has not been directly analyzed. RESULTS We report that the three WRKYs are involved in plant responses to abscisic acid (ABA) and abiotic stress. Through analysis of single, double, and triple mutants and overexpression lines for the WRKY genes, we have shown that WRKY18 and WRKY60 have a positive effect on plant ABA sensitivity for inhibition of seed germination and root growth. The same two WRKY genes also enhance plant sensitivity to salt and osmotic stress. WRKY40, on the other hand, antagonizes WRKY18 and WRKY60 in the effect on plant sensitivity to ABA and abiotic stress in germination and growth assays. Both WRKY18 and WRKY40 are rapidly induced by ABA, while induction of WRKY60 by ABA is delayed. ABA-inducible expression of WRKY60 is almost completely abolished in the wrky18 and wrky40 mutants. WRKY18 and WRKY40 recognize a cluster of W-box sequences in the WRKY60 promoter and activate WRKY60 expression in protoplasts. Thus, WRKY60 might be a direct target gene of WRKY18 and WRKY40 in ABA signaling. Using a stable transgenic reporter/effector system, we have shown that both WRKY18 and WRKY60 act as weak transcriptional activators while WRKY40 is a transcriptional repressor in plant cells. CONCLUSIONS We propose that the three related WRKY transcription factors form a highly interacting regulatory network that modulates gene expression in both plant defense and stress responses by acting as either transcription activator or repressor.
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Affiliation(s)
- Han Chen
- State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhibing Lai
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-2054, USA
| | - Junwei Shi
- State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yong Xiao
- State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhixiang Chen
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-2054, USA
| | - Xinping Xu
- State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
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Zhu J, Lee BH, Dellinger M, Cui X, Zhang C, Wu S, Nothnagel EA, Zhu JK. A cellulose synthase-like protein is required for osmotic stress tolerance in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 63:128-40. [PMID: 20409003 PMCID: PMC3061338 DOI: 10.1111/j.1365-313x.2010.04227.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Osmotic stress imposed by soil salinity and drought stress significantly affects plant growth and development, but osmotic stress sensing and tolerance mechanisms are not well understood. Forward genetic screens using a root-bending assay have previously identified salt overly sensitive (sos) mutants of Arabidopsis that fall into five loci, SOS1 to SOS5. These loci are required for the regulation of ion homeostasis or cell expansion under salt stress, but do not play a major role in plant tolerance to the osmotic stress component of soil salinity or drought. Here we report an additional sos mutant, sos6-1, which defines a locus essential for osmotic stress tolerance. sos6-1 plants are hypersensitive to salt stress and osmotic stress imposed by mannitol or polyethylene glycol in culture media or by water deficit in the soil. SOS6 encodes a cellulose synthase-like protein, AtCSLD5. Only modest differences in cell wall chemical composition could be detected, but we found that sos6-1 mutant plants accumulate high levels of reactive oxygen species (ROS) under osmotic stress and are hypersensitive to the oxidative stress reagent methyl viologen. The results suggest that SOS6/AtCSLD5 is not required for normal plant growth and development but has a critical role in osmotic stress tolerance and this function likely involves its regulation of ROS under stress.
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Affiliation(s)
- Jianhua Zhu
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA.
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Sun W, Xu X, Zhu H, Liu A, Liu L, Li J, Hua X. Comparative Transcriptomic Profiling of a Salt-Tolerant Wild Tomato Species and a Salt-Sensitive Tomato Cultivar. ACTA ACUST UNITED AC 2010; 51:997-1006. [DOI: 10.1093/pcp/pcq056] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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12
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Leidi EO, Barragán V, Rubio L, El-Hamdaoui A, Ruiz MT, Cubero B, Fernández JA, Bressan RA, Hasegawa PM, Quintero FJ, Pardo JM. The AtNHX1 exchanger mediates potassium compartmentation in vacuoles of transgenic tomato. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 61:495-506. [PMID: 19912566 DOI: 10.1111/j.1365-313x.2009.04073.x] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
NHX-type antiporters in the tonoplast have been reported to increase the salt tolerance of various plants species, and are thought to mediate the compartmentation of Na(+) in vacuoles. However, all isoforms characterized so far catalyze both Na(+)/H(+) and K(+)/H(+) exchange. Here, we show that AtNHX1 has a critical involvement in the subcellular partitioning of K(+), which in turn affects plant K(+) nutrition and Na(+) tolerance. Transgenic tomato plants overexpressing AtNHX1 had larger K(+) vacuolar pools in all growth conditions tested, but no consistent enhancement of Na(+) accumulation was observed under salt stress. Plants overexpressing AtNHX1 have a greater capacity to retain intracellular K(+) and to withstand salt-shock. Under K(+)-limiting conditions, greater K(+) compartmentation in the vacuole occurred at the expense of the cytosolic K(+) pool, which was lower in transgenic plants. This caused the early activation of the high-affinity K(+) uptake system, enhanced K(+) uptake by roots, and increased the K(+) content in plant tissues and the xylem sap of transformed plants. Our results strongly suggest that NHX proteins are likely candidates for the H(+)-linked K(+) transport that is thought to facilitate active K(+) uptake at the tonoplast, and the partitioning of K(+) between vacuole and cytosol.
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Affiliation(s)
- Eduardo O Leidi
- Instituto de Recursos Naturales y Agrobiología (IRNASE), Consejo Superior de Investigaciones Científicas, Reina Mercedes, 10, Sevilla - 41012, Spain
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Posé D, Castanedo I, Borsani O, Nieto B, Rosado A, Taconnat L, Ferrer A, Dolan L, Valpuesta V, Botella MA. Identification of the Arabidopsis dry2/sqe1-5 mutant reveals a central role for sterols in drought tolerance and regulation of reactive oxygen species. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:63-76. [PMID: 19309460 DOI: 10.1111/j.1365-313x.2009.03849.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Squalene epoxidase enzymes catalyse the conversion of squalene into 2,3-oxidosqualene, the precursor of cyclic triterpenoids. Here we report that the Arabidopsis drought hypersensitive/squalene epoxidase 1-5 (dry2/sqe1-5) mutant, identified by its extreme hypersensitivity to drought stress, has altered stomatal responses and root defects because of a point mutation in the SQUALENE EPOXIDASE 1 (SQE1) gene. GC-MS analysis indicated that the dry2/sqe1-5 mutant has altered sterol composition in roots but wild-type sterol composition in shoots, indicating an essential role for SQE1 in root sterol biosynthesis. Importantly, the stomatal and root defects of the dry2/sqe1-5 mutant are associated with altered production of reactive oxygen species. As RHD2 NADPH oxidase is de-localized in dry2/sqe1-5 root hairs, we propose that sterols play an essential role in the localization of NADPH oxidases required for regulation of reactive oxygen species, stomatal responses and drought tolerance.
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Affiliation(s)
- David Posé
- Departamento de Biología Molecular y Bioquímica, Universidad de Málaga, 29071 Málaga, Spain
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Sirichandra C, Wasilewska A, Vlad F, Valon C, Leung J. The guard cell as a single-cell model towards understanding drought tolerance and abscisic acid action. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:1439-63. [PMID: 19181866 DOI: 10.1093/jxb/ern340] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Stomatal guard cells are functionally specialized epidermal cells usually arranged in pairs surrounding a pore. Changes in ion fluxes, and more specifically osmolytes, within the guard cells drive opening/closing of the pore, allowing gas exchange while limiting water loss through evapo-transpiration. Adjustments of the pore aperture to optimize these conflicting needs are thus centrally important for land plants to survive, especially with the rise in CO(2) associated with global warming and increasing water scarcity this century. The basic biophysical events in modulating membrane transport have been gradually delineated over two decades. Genetics and molecular approaches in recent years have complemented and extended these earlier studies to identify major regulatory nodes. In Arabidopsis, the reference for guard cell genetics, stomatal opening driven by K(+) entry is mainly through KAT1 and KAT2, two voltage-gated K(+) inward-rectifying channels that are activated on hyperpolarization of the plasma membrane principally by the OST2 H(+)-ATPase (proton pump coupled to ATP hydrolysis). By contrast, stomatal closing is caused by K(+) efflux mainly through GORK, the outward-rectifying channel activated by membrane depolarization. The depolarization is most likely initiated by SLAC1, an anion channel distantly related to the dicarboxylate/malic acid transport protein found in fungi and bacteria. Beyond this established framework, there is also burgeoning evidence for the involvement of additional transporters, such as homologues to the multi-drug resistance proteins (or ABC transporters) as intimated by several pharmacological and reverse genetics studies. General inhibitors of protein kinases and protein phosphatases have been shown to profoundly affect guard cell membrane transport properties. Indeed, the first regulatory enzymes underpinning these transport processes revealed genetically were several protein phosphatases of the 2C class and the OST1 kinase, a member of the SnRK2 family. Taken together, these results are providing the first glimpses of an emerging signalling complex critical for modulating the stomatal aperture in response to environmental stimuli.
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Affiliation(s)
- Caroline Sirichandra
- Institut des Sciences du Végetal, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France
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Attia H, Arnaud N, Karray N, Lachaâl M. Long-term effects of mild salt stress on growth, ion accumulation and superoxide dismutase expression of Arabidopsis rosette leaves. PHYSIOLOGIA PLANTARUM 2008; 132:293-305. [PMID: 18275461 DOI: 10.1111/j.1399-3054.2007.01009.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Arabidopsis thaliana plants (wild-type accessions Col and N1438) were submitted to a prolonged, mild salt stress using two types of protocols. These protocols allowed salt-treated plants to absorb nutrients either through a part of their root system maintained in control medium (split-rooted plants) or during episodes on control medium alternating with salt application (salt alternation experiment). Full-salt treatments (salt applied continuously to whole root system) resulted in severe (but non-lethal) growth inhibition. This effect was partly alleviated in split-rooted plants on mixed salt-control medium and in plants submitted to salt-control medium alternation. The activity of the various isoforms of superoxide dismutases (SODs) did not appreciably change with the treatments. The abundance of the mRNAs of the seven SOD genes present in Arabidopsis genome was determined using real-time polymerase chain reaction. The two protocols gave qualitatively identical results. The expression level was increased by full-salt treatments for some genes and diminished for other genes. However, the nature of these genes differed according to the accessions: the responses to salt of FSD1 and MSD were opposite in Col and N1438. In Col, salt treatments inhibited the expression of FSD1 and strongly stimulated that of CSD1 and MSD. In N1438, the stimulation by salt concerned FSD1 and CSD1 and MSD expression being inhibited. In both accessions, the expression of CSD2 and CSD3 was lowered by salt. For all genes, the treatments that mitigated stress partially restored SOD expression to control level. Thus, the changes in SOD transcript abundance accurately reflected the severity of the salt stress.
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Affiliation(s)
- Houneida Attia
- Physiologie et Biochimie de la Tolérance au Sel des Plantes, Faculté des Sciences de Tunis, Campus Universitaire, 2092 Tunis El Manar, Tunisia
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16
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Li J, Du Y, Fang C. Developing an Iridium Oxide Film Modified Microelectrode for Microscale Measurement of pH. ELECTROANAL 2007. [DOI: 10.1002/elan.200603753] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Ouyang B, Yang T, Li H, Zhang L, Zhang Y, Zhang J, Fei Z, Ye Z. Identification of early salt stress response genes in tomato root by suppression subtractive hybridization and microarray analysis. JOURNAL OF EXPERIMENTAL BOTANY 2007; 58:507-20. [PMID: 17210988 DOI: 10.1093/jxb/erl258] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
High salinity is one of the most serious threats to crop production. To understand the molecular basis of plant responses to salt stress better, suppression subtractive hybridization (SSH) and microarray approaches were combined to identify the potential important or novel genes involved in the early stage of tomato responses to severe salt stress. First, SSH libraries were constructed for the root tissue of two cultivated tomato (Solanum lycopersicum) genotypes: LA2711, a salt-tolerant cultivar, and ZS-5, a salt-sensitive cultivar, to compare salt treatment and non-treatment plants. Then a subset of clones from these SSH libraries were used to construct a tomato cDNA array and microarray analysis was carried out to verify the expression changes of this set of clones upon a high concentration of salt treatment at various time points compared to the corresponding non-treatment controls. A total of 201 non-redundant genes that were differentially expressed upon 30 min of severe salt stress either in LA2711 or ZS-5 were identified from microarray analysis; most of these genes have not previously been reported to be associated with salt stress. The diversity of the putative functions of these genes indicated that salt stress resulted in a complex response in tomato plants.
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Affiliation(s)
- Bo Ouyang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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Rosado A, Schapire AL, Bressan RA, Harfouche AL, Hasegawa PM, Valpuesta V, Botella MA. The Arabidopsis tetratricopeptide repeat-containing protein TTL1 is required for osmotic stress responses and abscisic acid sensitivity. PLANT PHYSIOLOGY 2006; 142:1113-26. [PMID: 16998088 PMCID: PMC1630727 DOI: 10.1104/pp.106.085191] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Mutations in the Arabidopsis (Arabidopsis thaliana) TETRATRICOPEPTIDE-REPEAT THIOREDOXIN-LIKE 1 (TTL1) cause reduced tolerance to NaCl and osmotic stress that is characterized by reduced root elongation, disorganization of the root meristem, and impaired osmotic responses during germination and seedling development. Expression analyses of genes involved in abscisic acid (ABA) biosynthesis and catabolism suggest that TTL1 is not involved in the regulation of ABA levels but is required for ABA-regulated responses. TTL1 regulates the transcript levels of several dehydration-responsive genes, such as the transcription factor DREB2A, and genes encoding dehydration response proteins, such as ERD1 (early response to dehydration 1), ERD3, and COR15a. The TTL1 gene encodes a novel plant protein with tetratricopeptide repeats and a region with homology to thioredoxin proteins. Based on homology searches, there are four TTL members in the Arabidopsis genome with similar intron-exon structure and conserved amino acid domains. Proteins containing tetratricopeptide repeat motifs act as scaffold-forming multiprotein complexes and are emerging as essential elements for plant hormonal responses (such as gibberellin responses and ethylene biosynthesis). In this report, we identify TTL1 as a positive regulator of ABA signaling during germination and seedling development under stress.
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Affiliation(s)
- Abel Rosado
- Departamento de Biología Molecular y Bioquímica Universidad de Málaga, 29010 Málaga, Spain
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Medina J, Rodríguez-Franco M, Peñalosa A, Carrascosa MJ, Neuhaus G, Salinas J. Arabidopsis mutants deregulated in RCI2A expression reveal new signaling pathways in abiotic stress responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2005; 42:586-97. [PMID: 15860016 DOI: 10.1111/j.1365-313x.2005.02400.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
To uncover new pathways involved in low-temperature signal transduction, we screened for mutants altered in cold-induced expression of RCI2A, an Arabidopsis gene that is not a member of the CBF/DREB1 regulon and is induced not only by low temperature but also by abscisic acid (ABA), dehydration (DH) and NaCl. This was accomplished by generating a line of Arabidopsis carrying a transgene consisting of the RCI2A promoter fused to the firefly luciferase coding sequence. A number of mutants showing low or high RCI2A expression in response to low temperature were identified. These mutants also displayed deregulated RCI2A expression in response to ABA, DH or NaCl. Interestingly, however, they were not altered in stress-induced expression of RD29A, a CBF/DREB1-target gene, suggesting that the mutations affect signaling intermediates of CBF/DREB1-independent regulatory pathways. Several mutants showed alterations in their tolerance to freezing, DH or salt stress, as well as in their ABA sensitivity, which indicates that the signaling intermediates defined by the corresponding mutations play an important role in Arabidopsis tolerance to abiotic stresses. Based on the mutants identified, we discuss the involvement of CBF/DREB1-independent pathways in modulating stress signaling.
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Affiliation(s)
- Joaquín Medina
- Departamento de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Carretera de la Coruña, Km. 7, 28040 Madrid, Spain
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20
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Rubio L, Rosado A, Linares-Rueda A, Borsani O, García-Sánchez MJ, Valpuesta V, Fernández JA, Botella MA. Regulation of K+ transport in tomato roots by the TSS1 locus. Implications in salt tolerance. PLANT PHYSIOLOGY 2004; 134:452-459. [PMID: 14684839 PMCID: PMC316324 DOI: 10.1104/pp.103.030361] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2003] [Revised: 08/31/2003] [Accepted: 09/22/2003] [Indexed: 05/24/2023]
Abstract
The tss1 tomato (Lycopersicon esculentum) mutant exhibited reduced growth in low K+ and hypersensitivity to Na+ and Li+. Increased Ca2+ in the culture medium suppressed the Na+ hypersensitivity and the growth defect on low K+ medium of tss1 seedlings. Interestingly, removing NH4+ from the growth medium suppressed all growth defects of tss1, suggesting a defective NH4(+)-insensitive component of K+ transport. We performed electrophysiological studies to understand the contribution of the NH4(+)-sensitive and -insensitive components of K+ transport in wild-type and tss1 roots. Although at 1 mm Ca2+ we found no differences in affinity for K+ uptake between wild type and tss1 in the absence of NH4+, the maximum depolarization value was about one-half in tss1, suggesting that a set of K+ transporters is inactive in the mutant. However, these transporters became active by raising the external Ca2+ concentration. In the presence of NH4+, a reduced affinity for K+ was observed in both types of seedlings, but tss1 at 1 mm Ca2+ exhibited a 2-fold higher Km than wild type did. This defect was again corrected by raising the external concentration of Ca2+. Therefore, membrane potential measurements in root cells indicated that tss1 is affected in both NH4(+)-sensitive and -insensitive components of K+ transport at low Ca2+ concentrations and that this defective transport is rescued by increasing the concentration of Ca2+. Our results suggest that the TSS1 gene product is part of a crucial pathway mediating the beneficial effects of Ca2+ involved in K+ nutrition and salt tolerance.
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Affiliation(s)
- Lourdes Rubio
- Departamento de Biología Vegetal, Universidad de Málaga, 29071 Málaga, Spain
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Borsani O, Cuartero J, Valpuesta V, Botella MA. Tomato tos1 mutation identifies a gene essential for osmotic tolerance and abscisic acid sensitivity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2002; 32:905-914. [PMID: 12492833 DOI: 10.1046/j.1365-313x.2002.01475.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Osmotic stress severely limits plant growth and agricultural productivity. We have used mutagenesis to identify plant genes that are required for osmotic stress tolerance in tomato. As a result, we have isolated a novel mutant in tomato (tos1) caused by a single recessive nuclear mutation that is hypersensitive to general osmotic stress. Growth measurements demonstrated that the tos1 mutant is less sensitive to intracellular abscisic acid (ABA) and this decreased ABA sensitivity of tos1 is a basic cellular trait expressed by the mutant at all developmental stages analysed. It is not caused by a deficiency in the synthesis of ABA because the tos1 seedlings accumulated more ABA than the wild type (WT) after osmotic stress. In contrast, the tss2 tomato mutant, which is also hypersensitive to osmotic stress, is hypersensitive to exogenous ABA. Comparative analysis of tos1 and tss2 indicates that appropriate ABA perception and signalling is essential for osmotic tolerance.
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Affiliation(s)
- Omar Borsani
- Departamento de Biología Molecular y Bioquímica, Universidad de Málaga, 29071 Málaga, Spain
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Klok EJ, Wilson IW, Wilson D, Chapman SC, Ewing RM, Somerville SC, Peacock WJ, Dolferus R, Dennis ES. Expression profile analysis of the low-oxygen response in Arabidopsis root cultures. THE PLANT CELL 2002; 14:2481-94. [PMID: 12368499 PMCID: PMC151230 DOI: 10.1105/tpc.004747] [Citation(s) in RCA: 254] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2002] [Accepted: 07/11/2002] [Indexed: 05/17/2023]
Abstract
We used DNA microarray technology to identify genes involved in the low-oxygen response of Arabidopsis root cultures. A microarray containing 3500 cDNA clones was screened with cDNA samples taken at various times (0.5, 2, 4, and 20 h) after transfer to low-oxygen conditions. A package of statistical tools identified 210 differentially expressed genes over the four time points. Principal component analysis showed the 0.5-h response to contain a substantially different set of genes from those regulated differentially at the other three time points. The differentially expressed genes included the known anaerobic proteins as well as transcription factors, signal transduction components, and genes that encode enzymes of pathways not known previously to be involved in low-oxygen metabolism. We found that the regulatory regions of genes with a similar expression profile contained similar sequence motifs, suggesting the coordinated transcriptional control of groups of genes by common sets of regulatory factors.
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Affiliation(s)
- Erik Jan Klok
- Commonwealth Scientific and Industrial Research Organization Plant Industry, Canberra, Australian Capital Territory 2601, Australia.
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Abstract
Recent progress has been made in the identification and characterization of the mechanisms that allow plants to tolerate high salt concentrations. The understanding of metabolic fluxes and the main constraints for the production of compatible solutes (i.e. feedback inhibition and the limitation of substrate supply) open up the possibility of genetically engineering entire pathways that could lead to the production of osmoprotectants. This, together with the identification of the different sodium transporters (in particular vacuolar and plasma membrane Na(+)/H(+) antiporters) that could provide the needed ion homeostasis during salt stress, opens the possibility of engineering crop plants with improved salt tolerance.
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Affiliation(s)
- Maris P Apse
- Department of Pomology, University of California, 1 Shields Avenue, Davis CA 95616, USA.
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