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Amsbury S, Hunt L, Elhaddad N, Baillie A, Lundgren M, Verhertbruggen Y, Scheller HV, Knox JP, Fleming AJ, Gray JE. Stomatal Function Requires Pectin De-methyl-esterification of the Guard Cell Wall. Curr Biol 2016; 26:2899-2906. [PMID: 27720618 PMCID: PMC5106435 DOI: 10.1016/j.cub.2016.08.021] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 07/06/2016] [Accepted: 08/05/2016] [Indexed: 12/12/2022]
Abstract
Stomatal opening and closure depends on changes in turgor pressure acting within guard cells to alter cell shape [1]. The extent of these shape changes is limited by the mechanical properties of the cells, which will be largely dependent on the structure of the cell walls. Although it has long been observed that guard cells are anisotropic due to differential thickening and the orientation of cellulose microfibrils [2], our understanding of the composition of the cell wall that allows them to undergo repeated swelling and deflation remains surprisingly poor. Here, we show that the walls of guard cells are rich in un-esterified pectins. We identify a pectin methylesterase gene, PME6, which is highly expressed in guard cells and required for stomatal function. pme6-1 mutant guard cells have walls enriched in methyl-esterified pectin and show a decreased dynamic range in response to triggers of stomatal opening/closure, including elevated osmoticum, suggesting that abrogation of stomatal function reflects a mechanical change in the guard cell wall. Altered stomatal function leads to increased conductance and evaporative cooling, as well as decreased plant growth. The growth defect of the pme6-1 mutant is rescued by maintaining the plants in elevated CO2, substantiating gas exchange analyses, indicating that the mutant stomata can bestow an improved assimilation rate. Restoration of PME6 rescues guard cell wall pectin methyl-esterification status, stomatal function, and plant growth. Our results establish a link between gene expression in guard cells and their cell wall properties, with a corresponding effect on stomatal function and plant physiology. The guard cell wall is distinguished by a relatively low level of methylated pectin Increased methyl pectin leads to stomata with a smaller dynamic range of movement These plants show increased evaporative cooling and decreased growth under drought Elevated CO2 restores mutant plant growth to normal
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Affiliation(s)
- Sam Amsbury
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Lee Hunt
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Nagat Elhaddad
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK; Department of Botany, University of Omar Al-Mukhtar, Al-Baida, Libya
| | - Alice Baillie
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Marjorie Lundgren
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Yves Verhertbruggen
- Biological Systems and Engineering Division and Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Henrik V Scheller
- Biological Systems and Engineering Division and Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - J Paul Knox
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Andrew J Fleming
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
| | - Julie E Gray
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
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Voothuluru P, Anderson JC, Sharp RE, Peck SC. Plasma membrane proteomics in the maize primary root growth zone: novel insights into root growth adaptation to water stress. PLANT, CELL & ENVIRONMENT 2016; 39:2043-2054. [PMID: 27341663 DOI: 10.1111/pce.12778] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 06/11/2016] [Indexed: 06/06/2023]
Abstract
Previous work on maize (Zea mays L.) primary root growth under water stress showed that cell elongation is maintained in the apical region of the growth zone but progressively inhibited further from the apex. These responses involve spatially differential and coordinated regulation of osmotic adjustment, modification of cell wall extensibility, and other cellular growth processes that are required for root growth under water-stressed conditions. As the interface between the cytoplasm and the apoplast (including the cell wall), the plasma membrane likely plays critical roles in these responses. Using a simplified method for enrichment of plasma membrane proteins, the developmental distribution of plasma membrane proteins was analysed in the growth zone of well-watered and water-stressed maize primary roots. The results identified 432 proteins with differential abundances in well-watered and water-stressed roots. The majority of changes involved region-specific patterns of response, and the identities of the water stress-responsive proteins suggest involvement in diverse biological processes including modification of sugar and nutrient transport, ion homeostasis, lipid metabolism, and cell wall composition. Integration of the distinct, region-specific plasma membrane protein abundance patterns with results from previous physiological, transcriptomic and cell wall proteomic studies reveals novel insights into root growth adaptation to water stress.
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Affiliation(s)
- Priyamvada Voothuluru
- Division of Plant Sciences, University of Missouri, Columbia, MO, 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO, 65211, USA
| | - Jeffrey C Anderson
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO, 65211, USA
- Division of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
| | - Robert E Sharp
- Division of Plant Sciences, University of Missouri, Columbia, MO, 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO, 65211, USA
| | - Scott C Peck
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO, 65211, USA
- Division of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
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53
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Mishra RC, Ghosh R, Bae H. Plant acoustics: in the search of a sound mechanism for sound signaling in plants. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:4483-94. [PMID: 27342223 DOI: 10.1093/jxb/erw235] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Being sessile, plants continuously deal with their dynamic and complex surroundings, identifying important cues and reacting with appropriate responses. Consequently, the sensitivity of plants has evolved to perceive a myriad of external stimuli, which ultimately ensures their successful survival. Research over past centuries has established that plants respond to environmental factors such as light, temperature, moisture, and mechanical perturbations (e.g. wind, rain, touch, etc.) by suitably modulating their growth and development. However, sound vibrations (SVs) as a stimulus have only started receiving attention relatively recently. SVs have been shown to increase the yields of several crops and strengthen plant immunity against pathogens. These vibrations can also prime the plants so as to make them more tolerant to impending drought. Plants can recognize the chewing sounds of insect larvae and the buzz of a pollinating bee, and respond accordingly. It is thus plausible that SVs may serve as a long-range stimulus that evokes ecologically relevant signaling mechanisms in plants. Studies have suggested that SVs increase the transcription of certain genes, soluble protein content, and support enhanced growth and development in plants. At the cellular level, SVs can change the secondary structure of plasma membrane proteins, affect microfilament rearrangements, produce Ca(2+) signatures, cause increases in protein kinases, protective enzymes, peroxidases, antioxidant enzymes, amylase, H(+)-ATPase / K(+) channel activities, and enhance levels of polyamines, soluble sugars and auxin. In this paper, we propose a signaling model to account for the molecular episodes that SVs induce within the cell, and in so doing we uncover a number of interesting questions that need to be addressed by future research in plant acoustics.
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Affiliation(s)
- Ratnesh Chandra Mishra
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbook 38541, Republic of Korea
| | - Ritesh Ghosh
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbook 38541, Republic of Korea
| | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbook 38541, Republic of Korea
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Qiao Z, Li CL, Zhang W. WRKY1 regulates stomatal movement in drought-stressed Arabidopsis thaliana. PLANT MOLECULAR BIOLOGY 2016; 91:53-65. [PMID: 26820136 DOI: 10.1007/s11103-016-0441-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 01/16/2016] [Indexed: 05/19/2023]
Abstract
A key response of plants to moisture stress is stomatal closure, a process mediated by the phytohormone abscisic acid (ABA). Closure is affected by changes in the turgor of the stomatal guard cell. The transcription factor WRKY1 is a part of the regulatory machinery underlying stomatal movements, and through this, in the plant's response to drought stress. The loss-of-function T-DNA insertion mutant wrky1 was particularly sensitive to ABA, with respect to both ion channel regulation and stomatal movements, and less sensitive to drought than the wild type. Complementation of the wrky1 mutant resulted in the recovery of the wild type phenotype. The WRKY1 product localized to the nucleus, and was shown able to bind to the W-box domain in the promoters of MYB2, ABCG40, DREB1A and ABI5, and thereby to control their transcription in response to drought stress or ABA treatment. WRKY1 is thought to act as a negative regulator in guard cell ABA signalling.
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Affiliation(s)
- Zhu Qiao
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Chun-Long Li
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Wei Zhang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China.
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55
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Segal AW. NADPH oxidases as electrochemical generators to produce ion fluxes and turgor in fungi, plants and humans. Open Biol 2016; 6:160028. [PMID: 27249799 PMCID: PMC4892433 DOI: 10.1098/rsob.160028] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 04/21/2016] [Indexed: 02/07/2023] Open
Abstract
The NOXs are a family of flavocytochromes whose basic structure has been largely conserved from algae to man. This is a very simple system. NADPH is generally available, in plants it is a direct product of photosynthesis, and oxygen is a largely ubiquitous electron acceptor, and the electron-transporting core of an FAD and two haems is the minimal required to pass electrons across the plasma membrane. These NOXs have been shown to be essential for diverse functions throughout the biological world and, lacking a clear mechanism of action, their effects have generally been attributed to free radical reactions. Investigation into the function of neutrophil leucocytes has demonstrated that electron transport through the prototype NOX2 is accompanied by the generation of a charge across the membrane that provides the driving force propelling protons and other ions across the plasma membrane. The contention is that the primary function of the NOXs is to supply the driving force to transport ions, the nature of which will depend upon the composition and characteristics of the local ion channels, to undertake a host of diverse functions. These include the generation of turgor in fungi and plants for the growth of filaments and invasion by appressoria in the former, and extension of pollen tubes and root hairs, and stomatal closure, in the latter. In neutrophils, they elevate the pH in the phagocytic vacuole coupled to other ion fluxes. In endothelial cells of blood vessels, they could alter luminal volume to regulate blood pressure and tissue perfusion.
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Affiliation(s)
- Anthony W Segal
- Division of Medicine, UCL, 5 University Street, London WC1E 6JJ, UK
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56
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Li CL, Wang M, Wu XM, Chen DH, Lv HJ, Shen JL, Qiao Z, Zhang W. THI1, a Thiamine Thiazole Synthase, Interacts with Ca2+-Dependent Protein Kinase CPK33 and Modulates the S-Type Anion Channels and Stomatal Closure in Arabidopsis. PLANT PHYSIOLOGY 2016; 170:1090-104. [PMID: 26662273 PMCID: PMC4734576 DOI: 10.1104/pp.15.01649] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 12/09/2015] [Indexed: 05/06/2023]
Abstract
Thiamine is required for both plant growth and development. Here, the involvement of a thiamine thiazole synthase, THI1, has been demonstrated in both guard cell abscisic acid (ABA) signaling and the drought response in Arabidopsis (Arabidopsis thaliana). THI1 overexpressors proved to be more sensitive to ABA than the wild type with respect to both the activation of guard cell slow type anion channels and stomatal closure; this effectively reduced the rate of water loss from the plant and thereby enhanced its level of drought tolerance. A yeast two-hybrid strategy was used to screen a cDNA library from epidermal strips of leaves for THI1 regulatory factors, and identified CPK33, a Ca(2+)-dependent protein kinase, as interactor with THI1 in a plasma membrane-delimited manner. Loss-of-function cpk33 mutants were hypersensitive to ABA activation of slow type anion channels and ABA-induced stomatal closure, while the CPK33 overexpression lines showed opposite phenotypes. CPK33 kinase activity was essential for ABA-induced stomatal closure. Consistent with their contrasting regulatory role over stomatal closure, THI1 suppressed CPK33 kinase activity in vitro. Together, our data reveal a novel regulatory role of thiamine thiazole synthase to kinase activity in guard cell signaling.
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Affiliation(s)
- Chun-Long Li
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Mei Wang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Xiao-Meng Wu
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Dong-Hua Chen
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Hong-Jun Lv
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Jian-Lin Shen
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Zhu Qiao
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Wei Zhang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
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57
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Hong D, Jeon BW, Kim SY, Hwang JU, Lee Y. The ROP2-RIC7 pathway negatively regulates light-induced stomatal opening by inhibiting exocyst subunit Exo70B1 in Arabidopsis. THE NEW PHYTOLOGIST 2016; 209:624-35. [PMID: 26451971 DOI: 10.1111/nph.13625] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/30/2015] [Indexed: 05/03/2023]
Abstract
Stomata are the tiny valves on the plant surface that mediate gas exchange between the plant and its environment. Stomatal opening needs to be tightly regulated to facilitate CO2 uptake and prevent excess water loss. Plant Rho-type (ROP) GTPase 2 (ROP2) is a molecular component of the system that negatively regulates light-induced stomatal opening. Previously, ROP-interactive Cdc42- and Rac-interactive binding motif-containing protein 7 (RIC7) was suggested to function downstream of ROP2. However, the underlying molecular mechanism remains unknown. To understand the mechanism by which RIC7 regulates light-induced stomatal opening, we analyzed the stomatal responses of ric7 mutant Arabidopsis plants and identified the target protein of RIC7 using a yeast two-hybrid screen. Light-induced stomatal opening was promoted by ric7 knockout, whereas it was inhibited by RIC7 overexpression, indicating that RIC7 negatively regulates stomatal opening in Arabidopsis. RIC7 interacted with exocyst subunit Exo70 family protein B1 (Exo70B1), a component of the vesicle trafficking machinery. RIC7 and Exo70B1 localized to the plasma membrane region under light or constitutively active ROP2 conditions. The knockout mutant of Exo70B1 and ric7/exo70b1 exhibited retarded light-induced stomatal opening. Our results suggest that ROP2 and RIC7 suppress excess stomatal opening by inhibiting Exo70B1, which most likely participates in the vesicle trafficking required for light-induced stomatal opening.
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Affiliation(s)
- Daewoong Hong
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Byeong Wook Jeon
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Soo Young Kim
- Departments of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 500-757, Korea
| | - Jae-Ung Hwang
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Youngsook Lee
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
- Division of Integrative Biosciences and Biotechnology, POSTECH, Pohang, 790-784, Korea
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58
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Shah SH, Ali S, Qureshi AA, Zia MA, Jalal-Ud-Din, Ali GM. WITHDRAWN: Physiological and biochemical characterization of tomato transgenic lines overexpressing Arabidopsis thaliana cold responsive-element binding factor 3 (AtCBF3) gene under chilling stress. J Biotechnol 2015:S0168-1656(15)30235-2. [PMID: 26732415 DOI: 10.1016/j.jbiotec.2015.12.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 12/19/2015] [Accepted: 12/22/2015] [Indexed: 11/16/2022]
Abstract
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Affiliation(s)
- Sabir Hussain Shah
- Department of Agricultural Sciences, Allama Iqbal Open University, Islamabad, Pakistan.
| | - Shaukat Ali
- National Institute for Genomics & Advanced Biotechnology (NIGAB), National Agricultural Research Centre (NARC), Islamabad, Pakistan
| | - Abdul Ahad Qureshi
- Department of Horticulture, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan
| | - Muhammad Amir Zia
- National Institute for Genomics & Advanced Biotechnology (NIGAB), National Agricultural Research Centre (NARC), Islamabad, Pakistan
| | - Jalal-Ud-Din
- Plant Physiology Program, National Agricultural Research Centre (NARC), Islamabad, Pakistan
| | - Ghulam Muhammad Ali
- National Institute for Genomics & Advanced Biotechnology (NIGAB), National Agricultural Research Centre (NARC), Islamabad, Pakistan
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59
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Lugassi N, Kelly G, Fidel L, Yaniv Y, Attia Z, Levi A, Alchanatis V, Moshelion M, Raveh E, Carmi N, Granot D. Expression of Arabidopsis Hexokinase in Citrus Guard Cells Controls Stomatal Aperture and Reduces Transpiration. FRONTIERS IN PLANT SCIENCE 2015; 6:1114. [PMID: 26734024 PMCID: PMC4679854 DOI: 10.3389/fpls.2015.01114] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 11/24/2015] [Indexed: 05/20/2023]
Abstract
Hexokinase (HXK) is a sugar-phosphorylating enzyme involved in sugar-sensing. It has recently been shown that HXK in guard cells mediates stomatal closure and coordinates photosynthesis with transpiration in the annual species tomato and Arabidopsis. To examine the role of HXK in the control of the stomatal movement of perennial plants, we generated citrus plants that express Arabidopsis HXK1 (AtHXK1) under KST1, a guard cell-specific promoter. The expression of KST1 in the guard cells of citrus plants has been verified using GFP as a reporter gene. The expression of AtHXK1 in the guard cells of citrus reduced stomatal conductance and transpiration with no negative effect on the rate of photosynthesis, leading to increased water-use efficiency. The effects of light intensity and humidity on stomatal behavior were examined in rooted leaves of the citrus plants. The optimal intensity of photosynthetically active radiation and lower humidity enhanced stomatal closure of AtHXK1-expressing leaves, supporting the role of sugar in the regulation of citrus stomata. These results suggest that HXK coordinates photosynthesis and transpiration and stimulates stomatal closure not only in annual species, but also in perennial species.
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Affiliation(s)
- Nitsan Lugassi
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Gilor Kelly
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Lena Fidel
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Yossi Yaniv
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Ziv Attia
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Asher Levi
- Institute of Agricultural Engineering, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Victor Alchanatis
- Institute of Agricultural Engineering, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - Menachem Moshelion
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Eran Raveh
- Department of Fruit Tree Sciences, Institute of Plant Sciences, Agricultural Research Organization, Gilat Research CenterNegev, Israel
| | - Nir Carmi
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
| | - David Granot
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani CenterBet Dagan, Israel
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60
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Liang S, Lu K, Wu Z, Jiang SC, Yu YT, Bi C, Xin Q, Wang XF, Zhang DP. A link between magnesium-chelatase H subunit and sucrose nonfermenting 1 (SNF1)-related protein kinase SnRK2.6/OST1 in Arabidopsis guard cell signalling in response to abscisic acid. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6355-69. [PMID: 26175350 PMCID: PMC4588886 DOI: 10.1093/jxb/erv341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Magnesium-chelatase H subunit [CHLH/putative abscisic acid (ABA) receptor ABAR] positively regulates guard cell signalling in response to ABA, but the molecular mechanism remains largely unknown. A member of the sucrose nonfermenting 1 (SNF1)-related protein kinase 2 family, SnRK2.6/open stomata 1 (OST1)/SRK2E, which plays a critical role in ABA signalling in Arabidopsis guard cells, interacts with ABAR/CHLH. Neither mutation nor over-expression of the ABAR gene affects significantly ABA-insensitive phenotypes of stomatal movement in the OST1 knockout mutant allele srk2e. However, OST1 over-expression suppresses ABA-insensitive phenotypes of the ABAR mutant allele cch in stomatal movement. These genetic data support that OST1 functions downstream of ABAR in ABA signalling in guard cells. Consistent with this, ABAR protein is phosphorylated, but independently of the OST1 protein kinase. Two ABAR mutant alleles, cch and rtl1, show ABA insensitivity in ABA-induced reactive oxygen species and nitric oxide production, as well as in ABA-activated phosphorylation of a K(+) inward channel KAT1 in guard cells, which is consistent with that observed in the pyr1 pyl1 pyl2 pyl4 quadruple mutant of the well-characterized ABA receptor PYR/PYL/RCAR family acting upstream of OST1. These findings suggest that ABAR shares, at least in part, downstream signalling components with PYR/PYL/RCAR receptors for ABA in guard cells; though cch and rtl1 show strong ABA-insensitive phenotypes in both ABA-induced stomatal closure and inhibition of stomatal opening, while the pyr1 pyl1 pyl2 pyl4 quadruple mutant shows strong ABA insensitivity only in ABA-induced stomatal closure. These data establish a link between ABAR/CHLH and SnRK2.6/OST1 in guard cell signalling in response to ABA.
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Affiliation(s)
- Shan Liang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Kai Lu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhen Wu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shang-Chuan Jiang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yong-Tao Yu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Chao Bi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qi Xin
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiao-Fang Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Da-Peng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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61
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Lehmann P, Or D. Effects of stomata clustering on leaf gas exchange. THE NEW PHYTOLOGIST 2015; 207:1015-25. [PMID: 25967110 DOI: 10.1111/nph.13442] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 03/17/2015] [Indexed: 05/13/2023]
Abstract
A general theoretical framework for quantifying the stomatal clustering effects on leaf gaseous diffusive conductance was developed and tested. The theory accounts for stomatal spacing and interactions among 'gaseous concentration shells'. The theory was tested using the unique measurements of Dow et al. (2014) that have shown lower leaf diffusive conductance for a genotype of Arabidopsis thaliana with clustered stomata relative to uniformly distributed stomata of similar size and density. The model accounts for gaseous diffusion: through stomatal pores; via concentration shells forming at pore apertures that vary with stomata spacing and are thus altered by clustering; and across the adjacent air boundary layer. Analytical approximations were derived and validated using a numerical model for 3D diffusion equation. Stomata clustering increases the interactions among concentration shells resulting in larger diffusive resistance that may reduce fluxes by 5-15%. A similar reduction in conductance was found for clusters formed by networks of veins. The study resolves ambiguities found in the literature concerning stomata end-corrections and stomatal shape, and provides a new stomata density threshold for diffusive interactions of overlapping vapor shells. The predicted reduction in gaseous exchange due to clustering, suggests that guard cell function is impaired, limiting stomatal aperture opening.
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Affiliation(s)
- Peter Lehmann
- Soil and Terrestrial Environmental Physics, ETH Zurich, Universitätstrasse 16, 8092, Zurich, Switzerland
| | - Dani Or
- Soil and Terrestrial Environmental Physics, ETH Zurich, Universitätstrasse 16, 8092, Zurich, Switzerland
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62
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Bi Z, Merl-Pham J, Uehlein N, Zimmer I, Mühlhans S, Aichler M, Walch AK, Kaldenhoff R, Palme K, Schnitzler JP, Block K. RNAi-mediated downregulation of poplar plasma membrane intrinsic proteins (PIPs) changes plasma membrane proteome composition and affects leaf physiology. J Proteomics 2015; 128:321-32. [PMID: 26248320 DOI: 10.1016/j.jprot.2015.07.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/16/2015] [Accepted: 07/23/2015] [Indexed: 11/19/2022]
Abstract
Plasma membrane intrinsic proteins (PIPs) are one subfamily of aquaporins that mediate the transmembrane transport of water. To reveal their function in poplar, we generated transgenic poplar plants in which the translation of PIP genes was downregulated by RNA interference investigated these plants with a comprehensive leaf plasma membrane proteome and physiome analysis. First, inhibition of PIP synthesis strongly altered the leaf plasma membrane protein composition. Strikingly, several signaling components and transporters involved in the regulation of stomatal movement were differentially regulated in transgenic poplars. Furthermore, hormonal crosstalk related to abscisic acid, auxin and brassinosteroids was altered, in addition to cell wall biosynthesis/cutinization, the organization of cellular structures and membrane trafficking. A physiological analysis confirmed the proteomic results. The leaves had wider opened stomata and higher net CO2 assimilation and transpiration rates as well as greater mesophyll conductance for CO2 (gm) and leaf hydraulic conductance (Kleaf). Based on these results, we conclude that PIP proteins not only play essential roles in whole leaf water and CO2 flux but have important roles in the regulation of stomatal movement.
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Affiliation(s)
- Zhen Bi
- Research Unit Environmental Simulation, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Juliane Merl-Pham
- Research Unit Protein Science-Core Facility Proteomics, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Norbert Uehlein
- Institute of Applied Plant Science, University of Technology Darmstadt, Schnittspahndtr.10, 64287 Darmstadt, Germany
| | - Ina Zimmer
- Research Unit Environmental Simulation, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Stefanie Mühlhans
- Research Unit Environmental Simulation, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Michaela Aichler
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Axel Karl Walch
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Ralf Kaldenhoff
- Institute of Applied Plant Science, University of Technology Darmstadt, Schnittspahndtr.10, 64287 Darmstadt, Germany
| | - Klaus Palme
- BIOSS Centre for Biological Signalling Studies, ZBSA Centre for Biosystems Studies, Faculty of Biology, Schänzlestr. 1, University of Freiburg, 79104 Freiburg, Germany
| | - Jörg-Peter Schnitzler
- Research Unit Environmental Simulation, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany
| | - Katja Block
- Research Unit Environmental Simulation, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Ingolstädter Landstr.1, 85764 Neuherberg, Germany.
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Shen L, Sun P, Bonnell VC, Edwards KJ, Hetherington AM, McAinsh MR, Roberts MR. Measuring stress signaling responses of stomata in isolated epidermis of graminaceous species. FRONTIERS IN PLANT SCIENCE 2015; 6:533. [PMID: 26217375 PMCID: PMC4499840 DOI: 10.3389/fpls.2015.00533] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 06/29/2015] [Indexed: 05/07/2023]
Abstract
Our current understanding of guard cell signaling pathways is derived from studies in a small number of model species. The ability to study stomatal responses in isolated epidermis has been an important factor in elucidating the mechanisms by which the stomata of these species respond to environmental stresses. However, such approaches have rarely been applied to study guard cell signaling in the stomata of graminaceous species (including many of the world's major crops), in which the guard cells have a markedly different morphology to those in other plants. Our understanding of guard cell signaling in these important species is therefore much more limited. Here, we describe a procedure for the isolation of abaxial epidermal peels from barley, wheat and Brachypodium distachyon. We show that isolated epidermis from these species contains viable guard cells that exhibit typical responses to abscisic acid (ABA) and CO2, as determined by measurements of stomatal apertures. We use the epidermal peel assay technique to investigate in more detail interactions between different environmental factors in barley guard cells, and demonstrate that stomatal closure in response to external CO2 is inhibited at higher temperatures, whilst sensitivity to ABA is enhanced at 30°C compared to 20 and 40°C.
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Affiliation(s)
- Lei Shen
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Peng Sun
- School of Biological Sciences, University of Bristol, Bristol, UK
| | | | - Keith J. Edwards
- School of Biological Sciences, University of Bristol, Bristol, UK
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Wang L, Ma X, Che Y, Hou L, Liu X, Zhang W. Extracellular ATP mediates H 2 S-regulated stomatal movements and guard cell K + current in a H 2 O 2 -dependent manner in Arabidopsis. Sci Bull (Beijing) 2015. [DOI: 10.1007/s11434-014-0659-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Vainonen JP, Kangasjärvi J. Plant signalling in acute ozone exposure. PLANT, CELL & ENVIRONMENT 2015; 38:240-52. [PMID: 24417414 DOI: 10.1111/pce.12273] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 12/17/2013] [Accepted: 12/27/2013] [Indexed: 05/08/2023]
Abstract
Exposure of plants to high ozone concentrations causes lesion formation in sensitive plants. Plant responses to ozone involve fast and massive changes in protein activities, gene expression and metabolism even before any tissue damage can be detected. Degradation of ozone and subsequent accumulation of reactive oxygen species (ROS) in the extracellular space activates several signalling cascades, which are integrated inside the cell into a fine-balanced network of ROS signalling. Reversible protein phosphorylation and degradation plays an important role in the regulation of signalling mechanisms in a complex crosstalk with plant hormones and calcium, an essential second messenger. In this review, we discuss the recent advances in understanding the molecular mechanisms of ozone uptake, perception and signalling pathways activated during the early steps of ozone response, and discuss the use of ozone as a tool to study the function of apoplastic ROS in signalling.
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Affiliation(s)
- Julia P Vainonen
- Plant Biology Division, Department of Biosciences, University of Helsinki, FI-00014, Helsinki, Finland
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66
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Tian W, Hou C, Ren Z, Pan Y, Jia J, Zhang H, Bai F, Zhang P, Zhu H, He Y, Luo S, Li L, Luan S. A molecular pathway for CO2 response in Arabidopsis guard cells. Nat Commun 2015; 6:6057. [DOI: 10.1038/ncomms7057] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 12/08/2014] [Indexed: 11/09/2022] Open
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Cotelle V, Leonhardt N. 14-3-3 Proteins in Guard Cell Signaling. FRONTIERS IN PLANT SCIENCE 2015; 6:1210. [PMID: 26858725 PMCID: PMC4729941 DOI: 10.3389/fpls.2015.01210] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 12/15/2015] [Indexed: 05/19/2023]
Abstract
Guard cells are specialized cells located at the leaf surface delimiting pores which control gas exchanges between the plant and the atmosphere. To optimize the CO2 uptake necessary for photosynthesis while minimizing water loss, guard cells integrate environmental signals to adjust stomatal aperture. The size of the stomatal pore is regulated by movements of the guard cells driven by variations in their volume and turgor. As guard cells perceive and transduce a wide array of environmental cues, they provide an ideal system to elucidate early events of plant signaling. Reversible protein phosphorylation events are known to play a crucial role in the regulation of stomatal movements. However, in some cases, phosphorylation alone is not sufficient to achieve complete protein regulation, but is necessary to mediate the binding of interactors that modulate protein function. Among the phosphopeptide-binding proteins, the 14-3-3 proteins are the best characterized in plants. The 14-3-3s are found as multiple isoforms in eukaryotes and have been shown to be involved in the regulation of stomatal movements. In this review, we describe the current knowledge about 14-3-3 roles in the regulation of their binding partners in guard cells: receptors, ion pumps, channels, protein kinases, and some of their substrates. Regulation of these targets by 14-3-3 proteins is discussed and related to their function in guard cells during stomatal movements in response to abiotic or biotic stresses.
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Affiliation(s)
- Valérie Cotelle
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPSCastanet-Tolosan, France
- *Correspondence: Valérie Cotelle,
| | - Nathalie Leonhardt
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS–CEA–Université Aix-MarseilleSaint-Paul-lez-Durance, France
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68
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Cotelle V, Leonhardt N. 14-3-3 Proteins in Guard Cell Signaling. FRONTIERS IN PLANT SCIENCE 2015. [PMID: 26858725 DOI: 10.3389/fpis.2015.01210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Guard cells are specialized cells located at the leaf surface delimiting pores which control gas exchanges between the plant and the atmosphere. To optimize the CO2 uptake necessary for photosynthesis while minimizing water loss, guard cells integrate environmental signals to adjust stomatal aperture. The size of the stomatal pore is regulated by movements of the guard cells driven by variations in their volume and turgor. As guard cells perceive and transduce a wide array of environmental cues, they provide an ideal system to elucidate early events of plant signaling. Reversible protein phosphorylation events are known to play a crucial role in the regulation of stomatal movements. However, in some cases, phosphorylation alone is not sufficient to achieve complete protein regulation, but is necessary to mediate the binding of interactors that modulate protein function. Among the phosphopeptide-binding proteins, the 14-3-3 proteins are the best characterized in plants. The 14-3-3s are found as multiple isoforms in eukaryotes and have been shown to be involved in the regulation of stomatal movements. In this review, we describe the current knowledge about 14-3-3 roles in the regulation of their binding partners in guard cells: receptors, ion pumps, channels, protein kinases, and some of their substrates. Regulation of these targets by 14-3-3 proteins is discussed and related to their function in guard cells during stomatal movements in response to abiotic or biotic stresses.
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Affiliation(s)
- Valérie Cotelle
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS Castanet-Tolosan, France
| | - Nathalie Leonhardt
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, France
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69
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Yang X, Wang SS, Wang M, Qiao Z, Bao CC, Zhang W. Arabidopsis thaliana calmodulin-like protein CML24 regulates pollen tube growth by modulating the actin cytoskeleton and controlling the cytosolic Ca(2+) concentration. PLANT MOLECULAR BIOLOGY 2014; 86:225-36. [PMID: 25139229 DOI: 10.1007/s11103-014-0220-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 06/23/2014] [Indexed: 05/10/2023]
Abstract
Cytosolic free calcium ([Ca(2+)]cyt), which is essential during pollen germination and pollen tube growth, can be sensed by calmodulin-like proteins (CMLs). The Arabidopsis thaliana genome encodes over 50 CMLs, the physiological role(s) of most of which are unknown. Here we show that the gene AtCML24 acts as a regulator of pollen germination and pollen tube extension, since the pollen produced by loss-of-function mutants germinated less rapidly than that of wild-type (WT) plants, the rate of pollen tube extension was slower, and the final length of the pollen tube was shorter. The [Ca(2+)]cyt within germinated pollen and extending pollen tubes produced by the cml24 mutant were higher than their equivalents in WT plants, and pollen tube extension was less sensitive to changes in external [K(+)] and [Ca(2+)]. The pollen and pollen tubes produced by cml24 mutants were characterized by a disorganized actin cytoskeleton and lowered sensitivity to the action of latrunculin B. The observations support an interaction between CML24 and [Ca(2+)]cyt and an involvement of CML24 in actin organization, thereby affecting pollen germination and pollen tube elongation.
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Affiliation(s)
- Xue Yang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
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70
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Li CL, Wang M, Ma XY, Zhang W. NRGA1, a putative mitochondrial pyruvate carrier, mediates ABA regulation of guard cell ion channels and drought stress responses in Arabidopsis. MOLECULAR PLANT 2014; 7:1508-21. [PMID: 24842572 DOI: 10.1093/mp/ssu061] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Abscisic acid (ABA) regulates ion channel activity and stomatal movements in response to drought and other stresses. Here, we show that the Arabidopsis thaliana gene NRGA1 is a putative mitochondrial pyruvate carrier which negatively regulates ABA-induced guard cell signaling. NRGA1 transcript was abundant in the A. thaliana leaf and particularly in the guard cells, and its product was directed to the mitochondria. The heterologous co-expression of NRGA1 and AtMPC1 in yeast complemented a loss-of-function mitochondrial pyruvate carrier (MPC) mutant. The nrga1 loss-of-function mutant was very sensitive to the presence of ABA in the context of stomatal movements, and exhibited a heightened tolerance to drought stress. Disruption of NRGA1 gene resulted in increased ABA inhibition of inward K(+) currents and ABA activation of slow anion currents in guard cells. The nrga1/NRGA1 functional complementation lines restored the mutant's phenotypes. Furthermore, transgenic lines of constitutively overexpressing NRGA1 showed opposite stomatal responses, reduced drought tolerance, and ABA sensitivity of guard cell inward K(+) channel inhibition and anion channel activation. Our findings highlight a putative role for the mitochondrial pyruvate carrier in guard cell ABA signaling in response to drought.
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Affiliation(s)
- Chun-Long Li
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Mei Wang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Xiao-Yan Ma
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
| | - Wei Zhang
- Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China
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71
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Wang F, Jia J, Wang Y, Wang W, Chen Y, Liu T, Shang Z. Hyperpolization-activated Ca(2+) channels in guard cell plasma membrane are involved in extracellular ATP-promoted stomatal opening in Vicia faba. JOURNAL OF PLANT PHYSIOLOGY 2014; 171:1241-7. [PMID: 25014259 DOI: 10.1016/j.jplph.2014.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 03/07/2014] [Accepted: 05/14/2014] [Indexed: 05/09/2023]
Abstract
Extracellular ATP (eATP) plays essential roles in plant growth, development, and stress tolerance. Extracellular ATP-regulated stomatal movement of Arabidopsis thaliana has been reported. Here, ATP was found to promote stomatal opening of Vicia faba in a dose-dependent manner. Three weakly hydrolysable ATP analogs (adenosine 5'-O-(3-thio) triphosphate (ATPγS), 3'-O-(4-benzoyl) benzoyl adenosine 5'-triphosphate (Bz-ATP) and 2-methylthio-adenosine 5'-triphosphate (2meATP)) showed similar effects, indicating that ATP acts as a signal molecule rather than an energy charger. ADP promoted stomatal opening, while AMP and adenosine did not affect stomatal movement. An ATP-promoted stomatal opening was blocked by the NADPH oxidase inhibitor diphenylene iodonium (DPI), the reductant dithiothreitol (DTT) or the Ca(2+) channel blockers GdCl3 and LaCl3. A hyperpolarization-activated Ca(2+) channel was detected in plasma membrane of guard cell protoplast. Extracellular ATP and weakly hydrolyzable ATP analogs activated this Ca(2+) channel significantly. Extracellular ATP-promoted Ca(2+) channel activation was markedly inhibited by DPI or DTT. These results indicated that eATP may promote stomatal opening via reactive oxygen species that regulate guard cell plasma membrane Ca(2+) channels.
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Affiliation(s)
- Fang Wang
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Juanjuan Jia
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Yufang Wang
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Weixia Wang
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Yuling Chen
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Ting Liu
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China
| | - Zhonglin Shang
- Hebei Key Laboratory of Molecular & Cellular Biology, Key Laboratory of Molecular & Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang 050016, Hebei, PR China.
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72
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Lawson T, Simkin AJ, Kelly G, Granot D. Mesophyll photosynthesis and guard cell metabolism impacts on stomatal behaviour. THE NEW PHYTOLOGIST 2014; 203:1064-1081. [PMID: 25077787 DOI: 10.1111/nph.12945] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 06/02/2014] [Indexed: 05/19/2023]
Abstract
Stomata control gaseous fluxes between the internal leaf air spaces and the external atmosphere. Guard cells determine stomatal aperture and must operate to ensure an appropriate balance between CO2 uptake for photosynthesis (A) and water loss, and ultimately plant water use efficiency (WUE). A strong correlation between A and stomatal conductance (gs ) is well documented and often observed, but the underlying mechanisms, possible signals and metabolites that promote this relationship are currently unknown. In this review we evaluate the current literature on mesophyll-driven signals that may coordinate stomatal behaviour with mesophyll carbon assimilation. We explore a possible role of various metabolites including sucrose and malate (from several potential sources; including guard cell photosynthesis) and new evidence that improvements in WUE have been made by manipulating sucrose metabolism within the guard cells. Finally we discuss the new tools and techniques available for potentially manipulating cell-specific metabolism, including guard and mesophyll cells, in order to elucidate mesophyll-derived signals that coordinate mesophyll CO2 demands with stomatal behaviour, in order to provide a mechanistic understanding of these processes as this may identify potential targets for manipulations in order to improve plant WUE and crop yield.
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Affiliation(s)
- Tracy Lawson
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Andrew J Simkin
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Gilor Kelly
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Bet-Dagan, 50250, Israel
| | - David Granot
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Bet-Dagan, 50250, Israel
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73
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Dumont J, Cohen D, Gérard J, Jolivet Y, Dizengremel P, LE Thiec D. Distinct responses to ozone of abaxial and adaxial stomata in three Euramerican poplar genotypes. PLANT, CELL & ENVIRONMENT 2014; 37:2064-2076. [PMID: 24506578 DOI: 10.1111/pce.12293] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 01/16/2014] [Accepted: 01/21/2014] [Indexed: 06/03/2023]
Abstract
Ozone induces stomatal sluggishness, which impacts photosynthesis and transpiration. Stomatal responses to variation of environmental parameters are slowed and reduced by ozone and may be linked to difference of ozone sensitivity. Here we determine the ozone effects on stomatal conductance of each leaf surface. Potential causes of this sluggish movement, such as ultrastructural or ionic fluxes modification, were studied independently on both leaf surfaces of three Euramerican poplar genotypes differing in ozone sensitivity and in stomatal behaviour. The element contents in guard cells were linked to the gene expression of ion channels and transporters involved in stomatal movements, directly in microdissected stomata. In response to ozone, we found a decrease in the stomatal conductance of the leaf adaxial surface correlated with high calcium content in guard cells compared with a slight decrease on the abaxial surface. No ultrastructural modifications of stomata were shown except an increase in the number of mitochondria. The expression of vacuolar H(+) /Ca(2+) -antiports (CAX1 and CAX3 homologs), β-carbonic anhydrases (βCA1 and βCA4) and proton H(+) -ATPase (AHA11) genes was strongly decreased under ozone treatment. The sensitive genotype characterized by constitutive slow stomatal response was also characterized by constitutive low expression of genes encoding vacuolar H(+) /Ca(2+) -antiports.
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Affiliation(s)
- Jennifer Dumont
- INRA, UMR 1137, Ecologie et Ecophysiologie Forestières, Champenoux, F-54280, France; Université de Lorraine, UMR 1137, Ecologie et Ecophysiologie Forestières, Vandoeuvre-lès-Nancy, F-54500, France; IFR110 EFABA, Vandoeuvre-lès-Nancy, F-54500, France
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74
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Ronzier E, Corratgé-Faillie C, Sanchez F, Prado K, Brière C, Leonhardt N, Thibaud JB, Xiong TC. CPK13, a noncanonical Ca2+-dependent protein kinase, specifically inhibits KAT2 and KAT1 shaker K+ channels and reduces stomatal opening. PLANT PHYSIOLOGY 2014; 166:314-26. [PMID: 25037208 PMCID: PMC4149717 DOI: 10.1104/pp.114.240226] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 07/15/2014] [Indexed: 05/18/2023]
Abstract
Ca(2) (+)-dependent protein kinases (CPKs) form a large family of 34 genes in Arabidopsis (Arabidopsis thaliana). Based on their dependence on Ca(2+), CPKs can be sorted into three types: strictly Ca(2+)-dependent CPKs, Ca(2+)-stimulated CPKs (with a significant basal activity in the absence of Ca(2+)), and essentially calcium-insensitive CPKs. Here, we report on the third type of CPK, CPK13, which is expressed in guard cells but whose role is still unknown. We confirm the expression of CPK13 in Arabidopsis guard cells, and we show that its overexpression inhibits light-induced stomatal opening. We combine several approaches to identify a guard cell-expressed target. We provide evidence that CPK13 (1) specifically phosphorylates peptide arrays featuring Arabidopsis K(+) Channel KAT2 and KAT1 polypeptides, (2) inhibits KAT2 and/or KAT1 when expressed in Xenopus laevis oocytes, and (3) closely interacts in plant cells with KAT2 channels (Förster resonance energy transfer-fluorescence lifetime imaging microscopy). We propose that CPK13 reduces stomatal aperture through its inhibition of the guard cell-expressed KAT2 and KAT1 channels.
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Affiliation(s)
- Elsa Ronzier
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Claire Corratgé-Faillie
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Frédéric Sanchez
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Karine Prado
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Christian Brière
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Nathalie Leonhardt
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Jean-Baptiste Thibaud
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Tou Cheu Xiong
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
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75
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Ou X, Gan Y, Chen P, Qiu M, Jiang K, Wang G. Stomata prioritize their responses to multiple biotic and abiotic signal inputs. PLoS One 2014; 9:e101587. [PMID: 25003527 PMCID: PMC4086820 DOI: 10.1371/journal.pone.0101587] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/06/2014] [Indexed: 11/27/2022] Open
Abstract
Stomata are microscopic pores in leaf epidermis that regulate gas exchange between plants and the environment. Being natural openings on the leaf surface, stomata also serve as ports for the invasion of foliar pathogenic bacteria. Each stomatal pore is enclosed by a pair of guard cells that are able to sense a wide spectrum of biotic and abiotic stresses and respond by precisely adjusting the pore width. However, it is not clear whether stomatal responses to simultaneously imposed biotic and abiotic signals are mutually dependent on each other. Here we show that a genetically engineered Escherichia coli strain DH5α could trigger stomatal closure in Vicia faba, an innate immune response that might depend on NADPH oxidase-mediated ROS burst. DH5α-induced stomatal closure could be abolished or disguised under certain environmental conditions like low [CO2], darkness, and drought, etc. Foliar spraying of high concentrations of ABA could reduce stomatal aperture in high humidity-treated faba bean plants. Consistently, the aggressive multiplication of DH5α bacteria in Vicia faba leaves under high humidity could be alleviated by exogenous application of ABA. Our data suggest that a successful colonization of bacteria on the leaf surface is correlated with stomatal aperture regulation by a specific set of environmental factors.
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Affiliation(s)
- Xiaobin Ou
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yi Gan
- College of Life Sciences, Zhejiang University, Hangzhou, China
- School of Agriculture and Food Sciences, Zhejiang A&F University, Hangzhou, P. R. China
| | - Peilei Chen
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Muqing Qiu
- School of Life Sciences, Shaoxing University, Shaoxing, P. R. China
| | - Kun Jiang
- College of Life Sciences, Zhejiang University, Hangzhou, China
- * E-mail: (KJ); (GXW)
| | - Genxuan Wang
- College of Life Sciences, Zhejiang University, Hangzhou, China
- * E-mail: (KJ); (GXW)
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76
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Xie Y, Mao Y, Zhang W, Lai D, Wang Q, Shen W. Reactive Oxygen Species-Dependent Nitric Oxide Production Contributes to Hydrogen-Promoted Stomatal Closure in Arabidopsis. PLANT PHYSIOLOGY 2014; 165:759-773. [PMID: 24733882 PMCID: PMC4044830 DOI: 10.1104/pp.114.237925] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 04/12/2014] [Indexed: 05/20/2023]
Abstract
The signaling role of hydrogen gas (H2) has attracted increasing attention from animals to plants. However, the physiological significance and molecular mechanism of H2 in drought tolerance are still largely unexplored. In this article, we report that abscisic acid (ABA) induced stomatal closure in Arabidopsis (Arabidopsis thaliana) by triggering intracellular signaling events involving H2, reactive oxygen species (ROS), nitric oxide (NO), and the guard cell outward-rectifying K+ channel (GORK). ABA elicited a rapid and sustained H2 release and production in Arabidopsis. Exogenous hydrogen-rich water (HRW) effectively led to an increase of intracellular H2 production, a reduction in the stomatal aperture, and enhanced drought tolerance. Subsequent results revealed that HRW stimulated significant inductions of NO and ROS synthesis associated with stomatal closure in the wild type, which were individually abolished in the nitric reductase mutant nitrate reductase1/2 (nia1/2) or the NADPH oxidase-deficient mutant rbohF (for respiratory burst oxidase homolog). Furthermore, we demonstrate that the HRW-promoted NO generation is dependent on ROS production. The rbohF mutant had impaired NO synthesis and stomatal closure in response to HRW, while these changes were rescued by exogenous application of NO. In addition, both HRW and hydrogen peroxide failed to induce NO production or stomatal closure in the nia1/2 mutant, while HRW-promoted ROS accumulation was not impaired. In the GORK-null mutant, stomatal closure induced by ABA, HRW, NO, or hydrogen peroxide was partially suppressed. Together, these results define a main branch of H2-regulated stomatal movement involved in the ABA signaling cascade in which RbohF-dependent ROS and nitric reductase-associated NO production, and subsequent GORK activation, were causally involved.
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Affiliation(s)
- Yanjie Xie
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
| | - Yu Mao
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
| | - Wei Zhang
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
| | - Diwen Lai
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
| | - Qingya Wang
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
| | - Wenbiao Shen
- College of Life Sciences (Y.X., Y.M., W.Z., D.L., W.S.) and Laboratory Center of Life Sciences (Q.W.), Nanjing Agricultural University, Nanjing 210095, China
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77
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Lawson T, Blatt MR. Stomatal size, speed, and responsiveness impact on photosynthesis and water use efficiency. PLANT PHYSIOLOGY 2014; 164:1556-70. [PMID: 24578506 PMCID: PMC3982722 DOI: 10.1104/pp.114.237107] [Citation(s) in RCA: 467] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 02/25/2014] [Indexed: 05/18/2023]
Abstract
The control of gaseous exchange between the leaf and bulk atmosphere by stomata governs CO₂ uptake for photosynthesis and transpiration, determining plant productivity and water use efficiency. The balance between these two processes depends on stomatal responses to environmental and internal cues and the synchrony of stomatal behavior relative to mesophyll demands for CO₂. Here we examine the rapidity of stomatal responses with attention to their relationship to photosynthetic CO₂ uptake and the consequences for water use. We discuss the influence of anatomical characteristics on the velocity of changes in stomatal conductance and explore the potential for manipulating the physical as well as physiological characteristics of stomatal guard cells in order to accelerate stomatal movements in synchrony with mesophyll CO₂ demand and to improve water use efficiency without substantial cost to photosynthetic carbon fixation. We conclude that manipulating guard cell transport and metabolism is just as, if not more likely to yield useful benefits as manipulations of their physical and anatomical characteristics. Achieving these benefits should be greatly facilitated by quantitative systems analysis that connects directly the molecular properties of the guard cells to their function in the field.
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Affiliation(s)
| | - Michael R. Blatt
- School of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom (T.L.); and
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom (M.R.B.)
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78
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León J, Castillo MC, Coego A, Lozano-Juste J, Mir R. Diverse functional interactions between nitric oxide and abscisic acid in plant development and responses to stress. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:907-21. [PMID: 24371253 DOI: 10.1093/jxb/ert454] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The extensive support for abscisic acid (ABA) involvement in the complex regulatory networks controlling stress responses and development in plants contrasts with the relatively recent role assigned to nitric oxide (NO). Because treatment with exogenous ABA leads to enhanced production of NO, it has been widely considered that NO participates downstream of ABA in controlling processes such as stomata movement, seed dormancy, and germination. However, data on leaf senescence and responses to stress suggest that the functional interaction between ABA and NO is more complex than previously thought, including not only cooperation but also antagonism. The functional relationship is probably determined by several factors including the time- and place-dependent pattern of accumulation of both molecules, the threshold levels, and the regulatory factors important for perception. These factors will determine the actions exerted by each regulator. Here, several examples of well-documented functional interactions between NO and ABA are analysed in light of the most recent reported data on seed dormancy and germination, stomata movements, leaf senescence, and responses to abiotic and biotic stresses.
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Affiliation(s)
- José León
- Plant Development and Hormone Action, Instituto de Biología Molecular y Celular de Plantas (CSIC-Universidad Politécnica de Valencia), Spain
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79
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Granot D, Kelly G, Stein O, David-Schwartz R. Substantial roles of hexokinase and fructokinase in the effects of sugars on plant physiology and development. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:809-19. [PMID: 24293612 DOI: 10.1093/jxb/ert400] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The basic requirements for plant growth are light, CO2, water, and minerals. However, the absorption and utilization of each of these requires investment on the part of the plant. The primary products of plants are sugars, and the hexose sugars glucose and fructose are the raw material for most of the metabolic pathways and organic matter in plants. To be metabolized, hexose sugars must first be phosphorylated. Only two families of enzymes capable of catalysing the essential irreversible phosphorylation of glucose and fructose have been identified in plants, hexokinases (HXKs) and fructokinases (FRKs). These hexose-phosphorylating enzymes appear to coordinate sugar production with the abilities to absorb light, CO2, water, and minerals. This review describes the long- and short-term effects mediated by HXK and FRK in various tissues, as well as the role of these enzymes in the coordination of sugar production with the absorption of light, CO2, water, and minerals.
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Affiliation(s)
- David Granot
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
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80
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Kar RK, Parvin N, Laha D. Differential role of ethylene and hydrogen peroxide in dark-induced stomatal closure. Pak J Biol Sci 2013; 16:1991-1996. [PMID: 24517017 DOI: 10.3923/pjbs.2013.1991.1996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Regulation of stomatal aperture is crucial in terrestrial plants for controlling water loss and gaseous exchange with environment. While much is known of signaling for stomatal opening induced by blue light and the role of hormones, little is known about the regulation of stomatal closing in darkness. The present study was aimed to verify their role in stomatal regulation in darkness. Epidermal peelings from the leaves of Commelina benghalensis were incubated in a defined medium in darkness for 1 h followed by a 1 h incubation in different test solutions [H2O2, propyl gallate, ethrel (ethylene), AgNO3, sodium orthovanadate, tetraethyl ammonium chloride, CaCl2, LaCl3, separately and in combination] before stomatal apertures were measured under the microscope. In the dark stomata remained closed under treatments with ethylene and propyl gallate but opened widely in the presence of H2O2 and AgNO3. The opening effect was largely unaffected by supplementing the treatment with Na-vanadate (PM H+ ATPase inhibitor) and tetraethyl ammonium chloride (K(+)-channel inhibitor) except that opening was significantly inhibited by the latter in presence of H2O2. On the other hand, H2O2 could not override the closing effect of ethylene at any concentrations while a marginal opening of stomata was found when Ag NO3 treatment was given together with propyl gallate. CaCl2 treatment opened stomata in the darkness while LaCl3 maintained stomata closed. A combination of LaCl3 and propyl gallate strongly promoted stomatal opening. A probable action of ethylene in closing stomata of Commelina benghalensis in dark has been proposed.
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Affiliation(s)
- R K Kar
- Plant Physiology and Biochemistry Laboratory, Department of Botany, Visva-Bharati University, Santiniketan-731 235, West Bengal, India
| | - N Parvin
- Department of Botany, Biology-1, Biocentre, Ludwig Maximillians, University of Munich, 82152 Martinsried, Germany
| | - D Laha
- Centre for Plant Molecular Biology, Eberhard Karls, University of Tuebingen, Auf der Morgenstelle 1, 72076 Tuebingen, Germany
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81
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Acharya BR, Jeon BW, Zhang W, Assmann SM. Open Stomata 1 (OST1) is limiting in abscisic acid responses of Arabidopsis guard cells. THE NEW PHYTOLOGIST 2013; 200:1049-63. [PMID: 24033256 DOI: 10.1111/nph.12469] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 07/22/2013] [Indexed: 05/19/2023]
Abstract
Open Stomata 1 (OST1) (SnRK2.6 or SRK2E), a serine/threonine protein kinase, is a positive regulator in abscisic acid (ABA)-mediated stomatal response, but OST1-regulation of K(+) and Ca(2+) currents has not been studied directly in guard cells and it is unknown whether OST1 activity is limiting in ABA-mediated stomatal responses. We employed loss-of-function and gain-of-function approaches to study native ABA responses of Arabidopsis guard cells. We performed stomatal aperture bioassays, patch clamp analyses and reactive oxygen species (ROS) measurements. ABA inhibition of inward K(+) channels and light-induced stomatal opening are reduced in ost1 mutants while transgenic plants overexpressing OST1 show ABA hypersensitivity in these responses. ost1 mutants are insensitive to ABA-induced stomatal closure, regulation of slow anion currents, Ca(2+) -permeable channel activation and ROS production while OST1 overexpressing lines are hypersensitive for these responses, resulting in accelerated stomatal closure in response to ABA. Overexpression of OST1 in planta in the absence of ABA application does not affect basal apertures or ion currents. Moreover, we demonstrate the physical interaction of OST1 with the inward K(+) channel KAT1, the anion channel SLAC1, and the NADPH oxidases AtrbohD and AtrbohF. Our findings support OST1 as a critical limiting component in ABA regulation of stomatal apertures, ion channels and NADPH oxidases in Arabidopsis guard cells.
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Affiliation(s)
- Biswa R Acharya
- Biology Department, Penn State University, University Park, PA, 16802, USA
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82
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AtALMT9 is a malate-activated vacuolar chloride channel required for stomatal opening in Arabidopsis. Nat Commun 2013; 4:1804. [PMID: 23653216 PMCID: PMC3644109 DOI: 10.1038/ncomms2815] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 03/27/2013] [Indexed: 01/30/2023] Open
Abstract
Water deficit strongly affects crop productivity. Plants control water loss and CO2 uptake by regulating the aperture of the stomatal pores within the leaf epidermis. Stomata aperture is regulated by the two guard cells forming the pore and changing their size in response to ion uptake and release. While our knowledge about potassium and chloride fluxes across the plasma membrane of guard cells is advanced, little is known about fluxes across the vacuolar membrane. Here we present the molecular identification of the long-sought-after vacuolar chloride channel. AtALMT9 is a chloride channel activated by physiological concentrations of cytosolic malate. Single-channel measurements demonstrate that this activation is due to a malate-dependent increase in the channel open probability. Arabidopsis thaliana atalmt9 knockout mutants exhibited impaired stomatal opening and wilt more slowly than the wild type. Our findings show that AtALMT9 is a vacuolar chloride channel having a major role in controlling stomata aperture. Aluminium-activated malate transporters are exclusive to plants, regulating the transport of ions across the membranes on which they are expressed. De Angeli and colleagues show that AtALMT9 acts as a vacuolar chloride channel that is activated by cytosolic malate, and that this regulates stomata aperture.
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83
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Chen DH, Acharya BR, Liu W, Zhang W. Interaction between Calcium and Actin in Guard Cell and Pollen Signaling Networks. PLANTS (BASEL, SWITZERLAND) 2013; 2:615-34. [PMID: 27137395 PMCID: PMC4844389 DOI: 10.3390/plants2040615] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 09/25/2013] [Accepted: 09/26/2013] [Indexed: 12/17/2022]
Abstract
Calcium (Ca(2+)) plays important roles in plant growth, development, and signal transduction. It is a vital nutrient for plant physical design, such as cell wall and membrane, and also serves as a counter-cation for biochemical, inorganic, and organic anions, and more particularly, its concentration change in cytosol is a ubiquitous second messenger in plant physiological signaling in responses to developmental and environmental stimuli. Actin cytoskeleton is well known for its importance in cellular architecture maintenance and its significance in cytoplasmic streaming and cell division. In plant cell system, the actin dynamics is a process of polymerization and de-polymerization of globular actin and filamentous actin and that acts as an active regulator for calcium signaling by controlling calcium evoked physiological responses. The elucidation of the interaction between calcium and actin dynamics will be helpful for further investigation of plant cell signaling networks at molecular level. This review mainly focuses on the recent advances in understanding the interaction between the two aforementioned signaling components in two well-established model systems of plant, guard cell, and pollen.
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Affiliation(s)
- Dong-Hua Chen
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Sciences, Shandong University, Jinan 250100, Shandong, China.
| | - Biswa R Acharya
- Biology Department, Penn State University, University Park, PA 16802, USA.
| | - Wei Liu
- High-Tech Research Center, Shandong Academy of Agricultural Sciences, Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Jinan 250100, Shandong, China.
| | - Wei Zhang
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Sciences, Shandong University, Jinan 250100, Shandong, China.
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84
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Kelly G, Moshelion M, David-Schwartz R, Halperin O, Wallach R, Attia Z, Belausov E, Granot D. Hexokinase mediates stomatal closure. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:977-88. [PMID: 23738737 DOI: 10.1111/tpj.12258] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 05/30/2013] [Accepted: 06/03/2013] [Indexed: 05/19/2023]
Abstract
Stomata, composed of two guard cells, are the gates whose controlled movement allows the plant to balance the demand for CO2 for photosynthesis with the loss of water through transpiration. Increased guard-cell osmolarity leads to the opening of the stomata and decreased osmolarity causes the stomata to close. The role of sugars in the regulation of stomata is not yet clear. In this study, we examined the role of hexokinase (HXK), a sugar-phosphorylating enzyme involved in sugar-sensing, in guard cells and its effect on stomatal aperture. We show here that increased expression of HXK in guard cells accelerates stomatal closure. We further show that this closure is induced by sugar and is mediated by abscisic acid. These findings support the existence of a feedback-inhibition mechanism that is mediated by a product of photosynthesis, namely sucrose. When the rate of sucrose production exceeds the rate at which sucrose is loaded into the phloem, the surplus sucrose is carried toward the stomata by the transpiration stream and stimulates stomatal closure via HXK, thereby preventing the loss of precious water.
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Affiliation(s)
- Gilor Kelly
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
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Takahashi Y, Ebisu Y, Kinoshita T, Doi M, Okuma E, Murata Y, Shimazaki KI. bHLH transcription factors that facilitate K⁺ uptake during stomatal opening are repressed by abscisic acid through phosphorylation. Sci Signal 2013; 6:ra48. [PMID: 23779086 DOI: 10.1126/scisignal.2003760] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Stomata open in response to light and close after exposure to abscisic acid (ABA). They regulate gas exchange between plants and the atmosphere, enabling plants to adapt to changing environmental conditions. ABA binding to receptors initiates a signaling cascade that involves protein phosphorylation. We show that ABA induced the phosphorylation of three basic helix-loop-helix (bHLH) transcription factors, called AKSs (ABA-responsive kinase substrates; AKS1, AKS2, and AKS3), in Arabidopsis guard cells. In their unphosphorylated state, AKSs facilitated stomatal opening through the transcription of genes encoding inwardly rectifying K⁺ channels. aks1aks2-1 double mutant plants showed decreases in light-induced stomatal opening, K⁺ accumulation in response to light, activity of inwardly rectifying K⁺ channels, and transcription of genes encoding major inwardly rectifying K⁺ channels without affecting ABA-mediated stomatal closure. Overexpression of potassium channel in Arabidopsis thaliana 1 (KAT1), which encodes a major inwardly rectifying K⁺ channel in guard cells, rescued the phenotype of aks1aks2-1 plants. AKS1 bound directly to the promoter of KAT1, an interaction that was attenuated after ABA-induced phosphorylation. The ABA agonist pyrabactin induced phosphorylation of AKSs. Our results demonstrate that the AKS family of bHLH transcription factors facilitates stomatal opening through the transcription of genes encoding inwardly rectifying K⁺ channels and that ABA suppresses the activity of these channels by triggering the phosphorylation of AKS family transcription factors.
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Affiliation(s)
- Yohei Takahashi
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 812-8581, Japan
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86
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Bak G, Lee EJ, Lee Y, Kato M, Segami S, Sze H, Maeshima M, Hwang JU, Lee Y. Rapid structural changes and acidification of guard cell vacuoles during stomatal closure require phosphatidylinositol 3,5-bisphosphate. THE PLANT CELL 2013; 25:2202-16. [PMID: 23757398 PMCID: PMC3723621 DOI: 10.1105/tpc.113.110411] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 05/13/2013] [Accepted: 05/23/2013] [Indexed: 05/08/2023]
Abstract
Rapid stomatal closure is essential for water conservation in plants and is thus critical for survival under water deficiency. To close stomata rapidly, guard cells reduce their volume by converting a large central vacuole into a highly convoluted structure. However, the molecular mechanisms underlying this change are poorly understood. In this study, we used pH-indicator dyes to demonstrate that vacuolar convolution is accompanied by acidification of the vacuole in fava bean (Vicia faba) guard cells during abscisic acid (ABA)-induced stomatal closure. Vacuolar acidification is necessary for the rapid stomatal closure induced by ABA, since a double mutant of the vacuolar H(+)-ATPase vha-a2 vha-a3 and vacuolar H(+)-PPase mutant vhp1 showed delayed stomatal closure. Furthermore, we provide evidence for the critical role of phosphatidylinositol 3,5-bisphosphate [PtdIns(3,5)P2] in changes in pH and morphology of the vacuole. Single and double Arabidopsis thaliana null mutants of phosphatidylinositol 3-phosphate 5-kinases (PI3P5Ks) exhibited slow stomatal closure upon ABA treatment compared with the wild type. Moreover, an inhibitor of PI3P5K reduced vacuolar acidification and convolution and delayed stomatal closure in response to ABA. Taken together, these results suggest that rapid ABA-induced stomatal closure requires PtdIns(3,5)P2, which is essential for vacuolar acidification and convolution.
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Affiliation(s)
- Gwangbae Bak
- POSTECH-UZH Cooperative Laboratory, Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Eun-Jung Lee
- POSTECH-UZH Global Research Laboratory, Department of Integrative Bioscience and Biotechnology, World Class University Program, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Yuree Lee
- POSTECH-UZH Cooperative Laboratory, Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Mariko Kato
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Shoji Segami
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Heven Sze
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742-5815
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Jae-Ung Hwang
- POSTECH-UZH Cooperative Laboratory, Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Youngsook Lee
- POSTECH-UZH Global Research Laboratory, Department of Integrative Bioscience and Biotechnology, World Class University Program, Pohang University of Science and Technology, Pohang 790-784, Korea
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87
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Nikinmaa E, Hölttä T, Hari P, Kolari P, Mäkelä A, Sevanto S, Vesala T. Assimilate transport in phloem sets conditions for leaf gas exchange. PLANT, CELL & ENVIRONMENT 2013; 36:655-69. [PMID: 22934921 DOI: 10.1111/pce.12004] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Carbon uptake and transpiration in plant leaves occurs through stomata that open and close. Stomatal action is usually considered a response to environmental driving factors. Here we show that leaf gas exchange is more strongly related to whole tree level transport of assimilates than previously thought, and that transport of assimilates is a restriction of stomatal opening comparable with hydraulic limitation. Assimilate transport in the phloem requires that osmotic pressure at phloem loading sites in leaves exceeds the drop in hydrostatic pressure that is due to transpiration. Assimilate transport thus competes with transpiration for water. Excess sugar loading, however, may block the assimilate transport because of viscosity build-up in phloem sap. Therefore, for given conditions, there is a stomatal opening that maximizes phloem transport if we assume that sugar loading is proportional to photosynthetic rate. Here we show that such opening produces the observed behaviour of leaf gas exchange. Our approach connects stomatal regulation directly with sink activity, plant structure and soil water availability as they all influence assimilate transport. It produces similar behaviour as the optimal stomatal control approach, but does not require determination of marginal cost of water parameter.
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Affiliation(s)
- Eero Nikinmaa
- Departments of Forest Sciences, University of Helsinki, Helsinki FI-00014, Finland.
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88
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Li LJ, Ren F, Gao XQ, Wei PC, Wang XC. The reorganization of actin filaments is required for vacuolar fusion of guard cells during stomatal opening in Arabidopsis. PLANT, CELL & ENVIRONMENT 2013; 36:484-97. [PMID: 22891733 DOI: 10.1111/j.1365-3040.2012.02592.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The reorganization of actin filaments (AFs) and vacuoles in guard cells is involved in the regulation of stomatal movement. However, it remains unclear whether there is any interaction between the reorganization of AFs and vacuolar changes during stomatal movement. Here, we report the relationship between the reorganization of AFs and vacuolar fusion revealed in pharmacological experiments, and characterizing stomatal opening in actin-related protein 2 (arp2) and arp3 mutants. Our results show that cytochalasin-D-induced depolymerization or phalloidin-induced stabilization of AFs leads to an increase in small unfused vacuoles during stomatal opening in wild-type (WT) Arabidopsis plants. Light-induced stomatal opening is retarded and vacuolar fusion in guard cells is impaired in the mutants, in which the reorganization and the dynamic parameters of AFs are aberrant compared with those of the WT. In WT, AFs tightly surround the small separated vacuoles, forming a ring that encircles the boundary membranes of vacuoles partly fused during stomatal opening. In contrast, in the mutants, most AFs and actin patches accumulate abnormally around the nuclei of the guard cells, which probably further impair vacuolar fusion and retard stomatal opening. Our results suggest that the reorganization of AFs regulates vacuolar fusion in guard cells during stomatal opening.
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Affiliation(s)
- Li-Juan Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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89
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West GM, Pascal BD, Ng LM, Soon FF, Melcher K, Xu HE, Chalmers MJ, Griffin PR. Protein conformation ensembles monitored by HDX reveal a structural rationale for abscisic acid signaling protein affinities and activities. Structure 2013; 21:229-35. [PMID: 23290725 DOI: 10.1016/j.str.2012.12.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 11/16/2012] [Accepted: 12/08/2012] [Indexed: 01/04/2023]
Abstract
Plants regulate growth and respond to environmental stress through abscisic acid (ABA) regulated pathways, and as such these pathways are of primary interest for biological and agricultural research. The ABA response is first perceived by the PYR/PYL/RCAR class of START protein receptors. These ABA activated receptors disrupt phosphatase inhibition of Snf1-related kinases (SnRKs), enabling kinase signaling. Here, insights into the structural mechanism of proteins in the ABA signaling pathway (the ABA receptor PYL2, HAB1 phosphatase, and two kinases, SnRK2.3 and 2.6) are discerned through hydrogen/deuterium exchange (HDX) mass spectrometry. HDX on the phosphatase in the presence of binding partners provides evidence for receptor-specific conformations involving the Trp385 "lock" that is necessary for signaling. Furthermore, kinase activity is linked to a more stable "closed" conformation. These solution-based studies complement the static crystal structures and provide a more detailed understanding of the ABA signaling pathway.
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Affiliation(s)
- Graham M West
- Department of Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, USA
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90
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Seidel T, Siek M, Marg B, Dietz KJ. Energization of vacuolar transport in plant cells and its significance under stress. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 304:57-131. [PMID: 23809435 DOI: 10.1016/b978-0-12-407696-9.00002-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The plant vacuole is of prime importance in buffering environmental perturbations and in coping with abiotic stress caused by, for example, drought, salinity, cold, or UV. The large volume, the efficient integration in anterograde and retrograde vesicular trafficking, and the dynamic equipment with tonoplast transporters enable the vacuole to fulfill indispensible functions in cell biology, for example, transient and permanent storage, detoxification, recycling, pH and redox homeostasis, cell expansion, biotic defence, and cell death. This review first focuses on endomembrane dynamics and then summarizes the functions, assembly, and regulation of secretory and vacuolar proton pumps: (i) the vacuolar H(+)-ATPase (V-ATPase) which represents a multimeric complex of approximately 800 kDa, (ii) the vacuolar H(+)-pyrophosphatase, and (iii) the plasma membrane H(+)-ATPase. These primary proton pumps regulate the cytosolic pH and provide the driving force for secondary active transport. Carriers and ion channels modulate the proton motif force and catalyze uptake and vacuolar compartmentation of solutes and deposition of xenobiotics or secondary compounds such as flavonoids. ABC-type transporters directly energized by MgATP complement the transport portfolio that realizes the multiple functions in stress tolerance of plants.
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Affiliation(s)
- Thorsten Seidel
- Biochemistry and Physiology of Plants, Faculty of Biology, Bielefeld University, Bielefeld, Germany.
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91
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Jin Z, Xue S, Luo Y, Tian B, Fang H, Li H, Pei Y. Hydrogen sulfide interacting with abscisic acid in stomatal regulation responses to drought stress in Arabidopsis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 62:41-46. [PMID: 23178483 DOI: 10.1016/j.plaphy.2012.10.017] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 10/29/2012] [Indexed: 05/19/2023]
Abstract
Hydrogen sulfide (H(2)S) plays a crucial role in the regulation of stomatal closure in plant response to drought stress, and l-cysteine desulfhydrase (LCD) has been identified as being mainly responsible for the degradation of cysteine to generate H(2)S. In view of the similar roles to abscisic acid (ABA), in this study, the lcd, aba3 and abi1 mutants were studied to investigate the close inter-relationship between H(2)S and ABA. The lcd mutant showed enlarged stomatal aperture and more sensitivity to drought stress than wild-type plants. Expression of Ca(2+) channel and outward-rectifying K(+) channel coding genes decreased in the lcd mutant, and conversely, expression of inward-rectifying K(+) increased. The stomatal aperture of aba3 and abi1 mutants decreased after treatment with NaHS (a H(2)S donor), but stomatal closure in responses to ABA was impaired in the lcd mutant. The expression of LCD and H(2)S production rate decreased in both the aba3 and abi1 mutants. Transcriptional expression of ABA receptor candidates was upregulated in the lcd mutant and decreased with NaHS treatment. The above results suggested that H(2)S may be an important link in stomatal regulation by ABA via ion channels; H(2)S affected the expression of ABA receptor candidates; and ABA also influenced H(2)S production. Thus, H(2)S interacted with ABA in the stomatal regulation responsible for drought stress in Arabidopsis.
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Affiliation(s)
- Zhuping Jin
- School of Life Science, Shanxi University, Taiyuan 030006, China
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92
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Sharma T, Dreyer I, Riedelsberger J. The role of K(+) channels in uptake and redistribution of potassium in the model plant Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2013; 4:224. [PMID: 23818893 PMCID: PMC3694395 DOI: 10.3389/fpls.2013.00224] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 06/09/2013] [Indexed: 05/17/2023]
Abstract
Potassium (K(+)) is inevitable for plant growth and development. It plays a crucial role in the regulation of enzyme activities, in adjusting the electrical membrane potential and the cellular turgor, in regulating cellular homeostasis and in the stabilization of protein synthesis. Uptake of K(+) from the soil and its transport to growing organs is essential for a healthy plant development. Uptake and allocation of K(+) are performed by K(+) channels and transporters belonging to different protein families. In this review we summarize the knowledge on the versatile physiological roles of plant K(+) channels and their behavior under stress conditions in the model plant Arabidopsis thaliana.
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Affiliation(s)
- Tripti Sharma
- Molecular Biology, Institute for Biochemistry and Biology, University of PotsdamPotsdam, Germany
- IMPRS-PMPG, Max-Planck Institute of Molecular Plant PhysiologyPotsdam, Germany
| | - Ingo Dreyer
- Centro de Biotecnologia y Genomica de Plantas, Universidad Politécnica de MadridMadrid, Spain
- *Correspondence: Ingo Dreyer, Plant Biophysics, Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus de Montegancedo, Carretera M-40, km 37.7, Pozuelo de Alarcón, Madrid E-28223, Spain e-mail:
| | - Janin Riedelsberger
- Molecular Biology, Institute for Biochemistry and Biology, University of PotsdamPotsdam, Germany
- IMPRS-PMPG, Max-Planck Institute of Molecular Plant PhysiologyPotsdam, Germany
- Janin Riedelsberger, Molecular Biology, Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24/25, House 20, D-14476 Potsdam, Germany e-mail:
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93
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Abstract
As one of the most important mineral nutrient elements, potassium (K(+)) participates in many plant physiological processes and determines the yield and quality of crop production. In this review, we summarize K(+) signaling processes and K(+) transport regulation in higher plants, especially in plant responses to K(+)-deficiency stress. Plants perceive external K(+) fluctuations and generate the initial K(+) signal in root cells. This signal is transduced into the cytoplasm and encoded as Ca(2+) and reactive oxygen species signaling. K(+)-deficiency-induced signals are subsequently decoded by cytoplasmic sensors, which regulate the downstream transcriptional and posttranslational responses. Eventually, plants produce a series of adaptive events in both physiological and morphological alterations that help them survive K(+) deficiency.
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Affiliation(s)
- Yi Wang
- State Key Laboratory of Plant Physiology and Biochemistry, National Center of Plant Gene Research (Beijing), College of Biological Sciences, China Agricultural University, Beijing 100193, China
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94
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Beguerisse-Dıaz M, Hernández-Gómez MC, Lizzul AM, Barahona M, Desikan R. Compound stress response in stomatal closure: a mathematical model of ABA and ethylene interaction in guard cells. BMC SYSTEMS BIOLOGY 2012; 6:146. [PMID: 23176679 PMCID: PMC3564773 DOI: 10.1186/1752-0509-6-146] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 11/01/2012] [Indexed: 11/10/2022]
Abstract
BACKGROUND Stomata are tiny pores in plant leaves that regulate gas and water exchange between the plant and its environment. Abscisic acid and ethylene are two well-known elicitors of stomatal closure when acting independently. However, when stomata are presented with a combination of both signals, they fail to close. RESULTS Toshed light on this unexplained behaviour, we have collected time course measurements of stomatal aperture and hydrogen peroxide production in Arabidopsis thaliana guard cells treated with abscisic acid, ethylene, and a combination of both. Our experiments show that stomatal closure is linked to sustained high levels of hydrogen peroxide in guard cells. When treated with a combined dose of abscisic acid and ethylene, guard cells exhibit increased antioxidant activity that reduces hydrogen peroxide levels and precludes closure. We construct a simplified model of stomatal closure derived from known biochemical pathways that captures the experimentally observed behaviour. CONCLUSIONS Our experiments and modelling results suggest a distinct role for two antioxidant mechanisms during stomatal closure: a slower, delayed response activated by a single stimulus (abscisic acid 'or' ethylene) and another more rapid 'and' mechanism that is only activated when both stimuli are present. Our model indicates that the presence of this rapid 'and' mechanism in the antioxidant response is key to explain the lack of closure under a combined stimulus.
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Affiliation(s)
- Mariano Beguerisse-Dıaz
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK
| | | | | | - Mauricio Barahona
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK
| | - Radhika Desikan
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
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95
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Zhang H, Gao Z, Zheng X, Zhang Z. The role of G-proteins in plant immunity. PLANT SIGNALING & BEHAVIOR 2012; 7:1284-8. [PMID: 22895102 PMCID: PMC3493415 DOI: 10.4161/psb.21431] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Heterotrimeric G-proteins play an important regulatory role in multiple physiological processes, including the plant immune response, and substantial progress has been made in elucidating the G-protein-mediated defense-signaling network. This mini-review discusses the importance of G-proteins in plant immunity. We also provide an overview of how G-proteins affect plant cell death and stomatal movement. Our recent studies demonstrated that G-proteins are involved in signal transduction and induction of stomatal closure and defense responses. We also discuss future directions for G-protein signaling studies involving plant immunity.
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Affiliation(s)
- Huajian Zhang
- Department of Plant Pathology; College of Plant Protection; Nanjing Agricultural University; Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects; Ministry of Agriculture; Nanjing, China
- Department of Plant Pathology; Anhui Agricultural University; Hefei, China
| | - Zhimou Gao
- Department of Plant Pathology; Anhui Agricultural University; Hefei, China
| | - Xiaobo Zheng
- Department of Plant Pathology; College of Plant Protection; Nanjing Agricultural University; Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects; Ministry of Agriculture; Nanjing, China
| | - Zhengguang Zhang
- Department of Plant Pathology; College of Plant Protection; Nanjing Agricultural University; Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects; Ministry of Agriculture; Nanjing, China
- Correspondence to: Zhengguang Zhang,
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96
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Zimmerli C, Ribot C, Vavasseur A, Bauer H, Hedrich R, Poirier Y. PHO1 expression in guard cells mediates the stomatal response to abscisic acid in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:199-211. [PMID: 22612335 DOI: 10.1111/j.1365-313x.2012.05058.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Stomatal opening and closing are driven by ion fluxes that cause changes in guard cell turgor and volume. This process is, in turn, regulated by environmental and hormonal signals, including light and the phytohormone abscisic acid (ABA). Here, we present genetic evidence that expression of PHO1 in guard cells of Arabidopsis thaliana is required for full stomatal responses to ABA. PHO1 is involved in the export of phosphate into the root xylem vessels and, as a result, the pho1 mutant is characterized by low shoot phosphate levels. In leaves, PHO1 was found expressed in guard cells and up-regulated following treatment with ABA. The pho1 mutant was unaffected in production of reactive oxygen species following ABA treatment, and in stomatal movements in response to light cues, high extracellular calcium, auxin, and fusicoccin. However, stomatal movements in response to ABA treatment were severely impaired, both in terms of induction of closure and inhibition of opening. Micro-grafting a pho1 shoot scion onto wild-type rootstock resulted in plants with normal shoot growth and phosphate content, but failed to restore normal stomatal response to ABA treatment. PHO1 knockdown using RNA interference specifically in guard cells of wild-type plants caused a reduced stomatal response to ABA. In agreement, specific expression of PHO1 in guard cells of pho1 plants complemented the mutant guard cell phenotype and re-established ABA sensitivity, although full functional complementation was dependent on shoot phosphate sufficiency. Together, these data reveal an important role for phosphate and the action of PHO1 in the stomatal response to ABA.
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Affiliation(s)
- Céline Zimmerli
- Département de Biologie Moléculaire Végétale, Biophore, Université de Lausanne, CH-1015 Lausanne, Switzerland
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97
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Hao LH, Wang WX, Chen C, Wang YF, Liu T, Li X, Shang ZL. Extracellular ATP promotes stomatal opening of Arabidopsis thaliana through heterotrimeric G protein α subunit and reactive oxygen species. MOLECULAR PLANT 2012; 5:852-64. [PMID: 22138967 DOI: 10.1093/mp/ssr095] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
In recent years, adenosine tri-phosphate (ATP) has been reported to exist in apoplasts of plant cells as a signal molecule. Extracellular ATP (eATP) plays important roles in plant growth, development, and stress tolerance. Here, extracellular ATP was found to promote stomatal opening of Arabidopsis thaliana in light and darkness. ADP, GTP, and weakly hydrolyzable ATP analogs (ATPγS, Bz-ATP, and 2meATP) showed similar effects, whereas AMP and adenosine did not affect stomatal movement. Apyrase inhibited stomatal opening. ATP-promoted stomatal opening was blocked by an NADPH oxidase inhibitor (diphenylene iodonium) or deoxidizer (dithiothreitol), and was impaired in null mutant of NADPH oxidase (atrbohD/F). Added ATP triggered ROS generation in guard cells via NADPH oxidase. ATP also induced Ca(2+) influx and H(+) efflux in guard cells. In atrbohD/F, ATP-induced ion flux was strongly suppressed. In null mutants of the heterotrimeric G protein α subunit, ATP-promoted stomatal opening, cytoplasmic ROS generation, Ca(2+) influx, and H(+) efflux were all suppressed. These results indicated that eATP-promoted stomatal opening possibly involves the heterotrimeric G protein, ROS, cytosolic Ca(2+), and plasma membrane H(+)-ATPase.
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Affiliation(s)
- Li-Hua Hao
- Key Laboratory of Molecular and Cell Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, PR China
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98
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Chen DH, Wang M, Wang HG, Zhang W. A type of voltage-dependent Ca2+ channel on Vicia faba guard cell plasma membrane outwardly permeates K+. PROTOPLASMA 2012; 249:699-708. [PMID: 21892599 DOI: 10.1007/s00709-011-0313-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Accepted: 08/11/2011] [Indexed: 05/31/2023]
Abstract
The fine regulation of stomatal aperture is important for both plant photosynthesis and transpiration, while stomatal closing is an essential plant response to biotic and abiotic stresses such as drought, salinity, wounding, and pathogens. Quick stomatal closing is primarily due to rapid solute loss. Cytosolic free calcium ([Ca(2+)](cyt)) is a ubiquitous second messenger, and its elevation or oscillation plays important roles in stomatal movements, which can be triggered by the opening of Ca(2+)-permeable channels on the plasma membrane. For Ca(2+)-permeable channel recordings, Ba(2+) is preferred as a charge-carrying ion because it has higher permeability to Ca(2+) channels and blocks K(+) channel activities to facilitate current recordings; however, it prevents visualization of Ca(2+) channels' K(+) permeability. Here, we employed Ca(2+) instead of Ba(2+) in recording Ca(2+)-permeable channels on Vicia faba guard cell plasma membrane to mimic physiological solute conditions inside guard cells more accurately. Inward Ca(2+) currents could be recorded at the single-channel level, and these currents could be inhibited by micromolar Gd(3+), but their reversal potential is far away from the theoretical equilibrium potential for Ca(2+). Further experiments showed that the discrepancy of the reversal potential of the recorded Ca(2+) currents is influenced by cytosolic K(+). This suggests that voltage-dependent Ca(2+) channels also mediate K(+) efflux at depolarization voltages. In addition, a new kind of high-conductance channels with fivefold to normal Ca(2+) channel and 18-fold to normal outward K(+) conductance was found. Our data presented here suggest that plants have their own saving strategies in their rapid response to stress stimuli, and multiple kinds of hyperpolarization-activated Ca(2+)-permeable channels coexist on plasma membranes.
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Affiliation(s)
- Dong-Hua Chen
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, Shandong, 271018, China
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99
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Chen ZH, Hills A, Bätz U, Amtmann A, Lew VL, Blatt MR. Systems dynamic modeling of the stomatal guard cell predicts emergent behaviors in transport, signaling, and volume control. PLANT PHYSIOLOGY 2012; 159:1235-51. [PMID: 22635112 PMCID: PMC3404696 DOI: 10.1104/pp.112.197350] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 05/23/2012] [Indexed: 05/17/2023]
Abstract
The dynamics of stomatal movements and their consequences for photosynthesis and transpirational water loss have long been incorporated into mathematical models, but none have been developed from the bottom up that are widely applicable in predicting stomatal behavior at a cellular level. We previously established a systems dynamic model incorporating explicitly the wealth of biophysical and kinetic knowledge available for guard cell transport, signaling, and homeostasis. Here we describe the behavior of the model in response to experimentally documented changes in primary pump activities and malate (Mal) synthesis imposed over a diurnal cycle. We show that the model successfully recapitulates the cyclic variations in H⁺, K⁺, Cl⁻, and Mal concentrations in the cytosol and vacuole known for guard cells. It also yields a number of unexpected and counterintuitive outputs. Among these, we report a diurnal elevation in cytosolic-free Ca²⁺ concentration and an exchange of vacuolar Cl⁻ with Mal, both of which find substantiation in the literature but had previously been suggested to require additional and complex levels of regulation. These findings highlight the true predictive power of the OnGuard model in providing a framework for systems analysis of stomatal guard cells, and they demonstrate the utility of the OnGuard software and HoTSig library in exploring fundamental problems in cellular physiology and homeostasis.
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Affiliation(s)
| | | | | | - Anna Amtmann
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom (Z.-H.C., A.H., U.B., A.A., M.R.B.); and Physiological Laboratory, University of Cambridge, Cambridge CB2 3EG, United Kingdom (V.L.L.)
| | - Virgilio L. Lew
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom (Z.-H.C., A.H., U.B., A.A., M.R.B.); and Physiological Laboratory, University of Cambridge, Cambridge CB2 3EG, United Kingdom (V.L.L.)
| | - Michael R. Blatt
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom (Z.-H.C., A.H., U.B., A.A., M.R.B.); and Physiological Laboratory, University of Cambridge, Cambridge CB2 3EG, United Kingdom (V.L.L.)
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100
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Zhang H, Wang M, Wang W, Li D, Huang Q, Wang Y, Zheng X, Zhang Z. Silencing of G proteins uncovers diversified plant responses when challenged by three elicitors in Nicotiana benthamiana. PLANT, CELL & ENVIRONMENT 2012; 35:72-85. [PMID: 21895695 DOI: 10.1111/j.1365-3040.2011.02417.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Signalling through heterotrimeric G protein composed of α-, β- and γ-subunits is essential in numerous physiological processes. Here we show that this prototypical G protein complex acts mechanistically by controlling elicitor sensitivity towards hypersensitive response (HR) and stomatal closure in Nicotiana benthamiana. Gα-, Gβ1-, and Gβ2-silenced plants were generated using virus-induced gene silencing. All silenced plants were treated with Xanthomonas oryzae harpin, Magnaporthe oryzae Nep1 and Phytophthora boehmeriae boehmerin, respectively. HR was dramatically impaired in Gα- and Gβ2-silenced plants treated with harpin, indicating that harpin-, rather than Nep1- or boehmerin-triggered HR, is Gα- and Gβ2-dependent. Moreover, all Gα-, Gβ1- and Gβ2-silenced plants significantly impaired elicitor-induced stomatal closure, elicitor-promoted nitric oxide (NO) production and active oxygen species accumulation in guard cells. To our knowledge, this is the first report of Gα and Gβ subunits involvement in stomatal closure in response to elicitors. Furthermore, silencing of Gα, Gβ1 and Gβ2 has an effect on the transcription of plant defence-related genes when challenged by three elicitors. In conclusion, silencing of G protein subunits results in many interesting plant cell responses, revealing that plant immunity systems employ both conserved and distinct G protein pathways to sense elicitors from distinct phytopathogens formed during plant-microbe evolution.
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Affiliation(s)
- Huajian Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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