1
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Lemonnier P, Lawson T. Calvin cycle and guard cell metabolism impact stomatal function. Semin Cell Dev Biol 2024; 155:59-70. [PMID: 36894379 DOI: 10.1016/j.semcdb.2023.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 03/01/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023]
Abstract
Stomatal conductance (gs) determines CO2 uptake for photosynthesis (A) and water loss through transpiration, which is essential for evaporative cooling and maintenance of optimal leaf temperature as well as nutrient uptake. Stomata adjust their aperture to maintain an appropriate balance between CO2 uptake and water loss and are therefore critical to overall plant water status and productivity. Although there is considerable knowledge regarding guard cell (GC) osmoregulation (which drives differences in GC volume and therefore stomatal opening and closing), as well as the various signal transduction pathways that enable GCs to sense and respond to different environmental stimuli, little is known about the signals that coordinate mesophyll demands for CO2. Furthermore, chloroplasts are a key feature in GCs of many species, however, their role in stomatal function is unclear and a subject of debate. In this review we explore the current evidence regarding the role of these organelles in stomatal behaviour, including GC electron transport and Calvin-Benson-Bassham (CBB) cycle activity as well as their possible involvement correlating gs and A along with other potential mesophyll signals. We also examine the roles of other GC metabolic processes in stomatal function.
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Affiliation(s)
- P Lemonnier
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - T Lawson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK.
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2
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Moraes TS, Rossi ML, Martinelli AP, Dornelas MC. Morphological and anatomical traits during development: Highlighting extrafloral nectaries in Passiflora organensis. Microsc Res Tech 2022; 85:2784-2794. [PMID: 35421272 DOI: 10.1002/jemt.24127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/09/2022] [Accepted: 03/31/2022] [Indexed: 11/11/2022]
Abstract
Passiflora organensis is a small herbaceous vine with characteristic morphological variations throughout its development. The plant bears button-shaped extrafloral nectaries exclusively in adult leaves. Extrafloral nectaries are structures that secrete nectar and play an important role in plant-animal interactions as a strategy for protecting plants against herbivory. In this work, we performed anatomical and ultrastructural studies to characterize P. organensis extrafloral nectaries during their secretory phase. We showed extrafloral nectaries in Passiflora organensis are composed of three distinct regions: nectary epidermis, nectariferous parenchyma, and subnectariferous parenchyma. Our data suggests that all nectary regions constitute a functional unit involved in nectar production and release. The high metabolic activity in the nectary cells is characterized by the juxtaposition of organelles such as mitochondria and plastids together plasmalemma. In addition, calcium oxalate crystals are frequently associated to the nectaries. An increasing concentration of calcium during leaf development and nectary differentiation was observed, corresponding to the calcium deposition as calcium oxalate crystals. This is the first description of extrafloral nectaries in Passiflora organensis that is a promising tropical model species for several studies.
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Affiliation(s)
- Tatiana S Moraes
- Plant Biotechnology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Mônica Lanzoni Rossi
- Plant Biotechnology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Adriana P Martinelli
- Plant Biotechnology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Marcelo C Dornelas
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
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3
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Vialet-Chabrand S, Matthews JSA, Lawson T. Light, power, action! Interaction of respiratory energy- and blue light-induced stomatal movements. New Phytol 2021; 231:2231-2246. [PMID: 34101837 DOI: 10.1111/nph.17538] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/26/2021] [Indexed: 05/07/2023]
Abstract
Although the signalling pathway of blue light (BL)-dependent stomatal opening is well characterized, little is known about the interspecific diversity, the role it plays in the regulation of gas exchange and the source of energy used to drive the commonly observed increase in pore aperture. Using a combination of red and BL under ambient and low [O2 ] (to inhibit respiration), the interaction between BL, photosynthesis and respiration in determining stomatal conductance was investigated. These findings were used to develop a novel model to predict the feedback between photosynthesis and stomatal conductance under these conditions. Here we demonstrate that BL-induced stomatal responses are far from universal, and that significant species-specific differences exist in terms of both rapidity and magnitude. Increased stomatal conductance under BL reduced photosynthetic limitation, at the expense of water loss. Moreover, we stress the importance of the synergistic effect of BL and respiration in driving rapid stomatal movements, especially when photosynthesis is limited. These observations will help reshape our understanding of diurnal gas exchange in order to exploit the dynamic coordination between the rate of carbon assimilation (A) and stomatal conductance (gs ), as a target for enhancing crop performance and water use efficiency.
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Affiliation(s)
| | - Jack S A Matthews
- School of Life Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Tracy Lawson
- School of Life Sciences, University of Essex, Colchester, CO4 3SQ, UK
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4
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Hung CY, Zhang J, Bhattacharya C, Li H, Kittur FS, Oldham CE, Wei X, Burkey KO, Chen J, Xie J. Transformation of Long-Lived Albino Epipremnum aureum 'Golden Pothos' and Restoring Chloroplast Development. Front Plant Sci 2021; 12:647507. [PMID: 34054894 PMCID: PMC8149757 DOI: 10.3389/fpls.2021.647507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 04/19/2021] [Indexed: 05/27/2023]
Abstract
Chloroplasts are organelles responsible for chlorophyll biosynthesis, photosynthesis, and biosynthesis of many metabolites, which are one of key targets for crop improvement. Elucidating and engineering genes involved in chloroplast development are important approaches for studying chloroplast functions as well as developing new crops. In this study, we report a long-lived albino mutant derived from a popular ornamental plant Epipremnum aureum 'Golden Pothos' which could be used as a model for analyzing the function of genes involved in chloroplast development and generating colorful plants. Albino mutant plants were isolated from regenerated populations of variegated 'Golden Pothos' whose albino phenotype was previously found to be due to impaired expression of EaZIP, encoding Mg-protoporphyrin IX monomethyl ester cyclase. Using petioles of the mutant plants as explants with a traceable sGFP gene, an efficient transformation system was developed. Expressing Arabidopsis CHL27 (a homolog of EaZIP) but not EaZIP in albino plants restored green color and chloroplast development. Interestingly, in addition to the occurrence of plants with solid green color, plants with variegated leaves and pale-yellow leaves were also obtained in the regenerated populations. Nevertheless, our study shows that these long-lived albino plants along with the established efficient transformation system could be used for creating colorful ornamental plants. This system could also potentially be used for investigating physiological processes associated with chlorophyll levels and chloroplast development as well as certain biological activities, which are difficult to achieve using green plants.
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Affiliation(s)
- Chiu-Yueh Hung
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Jianhui Zhang
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Chayanika Bhattacharya
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Hua Li
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Farooqahmed S. Kittur
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Carla E. Oldham
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Xiangying Wei
- Institute of Oceanography, Minjiang University, Fuzhou, China
| | - Kent O. Burkey
- USDA-ARS Plant Science Research Unit, Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, United States
| | - Jianjun Chen
- Environmental Horticulture Department, Mid-Florida Research and Education Center, University of Florida, Apopka, FL, United States
| | - Jiahua Xie
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
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5
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Xiang Q, Lott AA, Assmann SM, Chen S. Advances and perspectives in the metabolomics of stomatal movement and the disease triangle. Plant Sci 2021; 302:110697. [PMID: 33288010 DOI: 10.1016/j.plantsci.2020.110697] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 05/20/2023]
Abstract
Crops are continuously exposed to microbial pathogens that cause tremendous yield losses worldwide. Stomatal pores formed by pairs of specialized guard cells in the leaf epidermis represent a major route of pathogen entry. Guard cells have an essential role as a first line of defense against pathogens. Metabolomics is an indispensable systems biology tool that has facilitated discovery and functional studies of metabolites that regulate stomatal movement in response to pathogens and other environmental factors. Guard cells, pathogens and environmental factors constitute the "stomatal disease triangle". The aim of this review is to highlight recent advances toward understanding the stomatal disease triangle in the context of newly discovered signaling molecules, hormone crosstalk, and consequent molecular changes that integrate pathogens and environmental sensing into stomatal immune responses. Future perspectives on emerging single-cell studies, multiomics and molecular imaging in the context of stomatal defense are discussed. Advances in this important area of plant biology will inform rational crop engineering and breeding for enhanced stomatal defense without disruption of other pathways that impact crop yield.
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Affiliation(s)
- Qingyuan Xiang
- Department of Biology, University of Florida Genetics Institute, Gainesville, FL, USA
| | - Aneirin A Lott
- Department of Biology, University of Florida Genetics Institute, Gainesville, FL, USA; Plant Molecular and Cellular Biology Program, University of Florida, FL, USA
| | - Sarah M Assmann
- Department of Biology, Pennsylvania State University, State College, PA, USA
| | - Sixue Chen
- Department of Biology, University of Florida Genetics Institute, Gainesville, FL, USA; Plant Molecular and Cellular Biology Program, University of Florida, FL, USA; Proteomics and Mass Spectrometry Facility, University of Florida, FL, USA.
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6
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Gloser V, Dvorackova M, Mota DH, Petrovic B, Gonzalez P, Geilfus CM. Early Changes in Nitrate Uptake and Assimilation Under Drought in Relation to Transpiration. Front Plant Sci 2020; 11:602065. [PMID: 33424901 PMCID: PMC7793686 DOI: 10.3389/fpls.2020.602065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/04/2020] [Indexed: 05/20/2023]
Abstract
Soil drying combined with nitrogen (N) deficiency poses a grave threat to agricultural crop production. The rate at which nitrate (NO3 -) is taken up depends partly on the uptake and transpiration of water. Rapid changes in nitrate assimilation, in contrast to other N forms, may serve as a component of the plant stress response to drought because nitrate assimilation may lead to changes in xylem pH. The modulation of xylem sap pH may be relevant for stomata regulation via the delivery of abscisic acid (ABA) to guard cells. In several factorial experiments, we investigated the interactions between nitrate and water availability on nitrate fate in the plant, as well as their possible implications for the early drought-stress response. We monitored the short-term response (2-6 days) of nitrate in biomass, transport to shoot and reduction in Pisum sativum, Hordeum vulgare, Vicia faba, and Nicotiana tabacum and correlated this with sap pH and transpiration rates (TRs). Cultivation on inorganic substrate ensured control over nutrient and water supply and prevented nodulation in legume species. NO3 - content in biomass decreased in most of the species under drought indicating significant decline in NO3 - uptake. Hordeum vulgare had the highest NO3 - concentrations in all organs even under drought and low NO3 - treatment. This species can likely respond much better to the combined adverse effects of low NO3 - and water scarcity. Nitrate reductase activity (NRA) was reduced in both roots and leaves of water deficient (WD) plants in all species except H. vulgare, presumably due to its high NO3 - contents. Further, transient reduction in NO3 - availability had no effect on sap pH. Therefore, it seems unlikely that NRA shifts from shoot root leading to the supposed alkalization of sap. We also did not observe any interactive effects of NO3 - and water deficiency on transpiration. Hence, as long as leaf NO3 - content remains stable, NO3 - availability in soil is not linked to short-term modulation of transpiration.
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Affiliation(s)
- Vít Gloser
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Michaela Dvorackova
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Daniel Hernandez Mota
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Bojana Petrovic
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Patricia Gonzalez
- Division of Controlled Environment Horticulture, Faculty of Life Sciences, Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences, Humboldt-University of Berlin, Berlin, Germany
| | - Christoph Martin Geilfus
- Division of Controlled Environment Horticulture, Faculty of Life Sciences, Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences, Humboldt-University of Berlin, Berlin, Germany
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7
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Silva LAS, Sampaio VF, Barbosa LCS, Machado M, Flores-Borges DNA, Sales JF, de Oliveira DC, Mayer JLS, Kuster VC, Rocha DI. Albinism in plants - far beyond the loss of chlorophyll: Structural and physiological aspects of wild-type and albino royal poinciana (Delonix regia) seedlings. Plant Biol (Stuttg) 2020; 22:761-768. [PMID: 32544284 DOI: 10.1111/plb.13146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/26/2020] [Indexed: 06/11/2023]
Abstract
The partial or complete loss of chlorophylls, or albinism, is a rare phenomenon in plants. In the present study, we provide the first report of the occurrence in albino Delonix regia seedlings and describe the morpho-physiological changes associated with albinism. Wild-type (WT) and albino seedlings were characterized. Leaflets samples were processed following common procedures for analysis with light, scanning and transmission electron microscopy. The chlorophyll a fluorescence parameters and the carbohydrate, lipid and soluble protein content were also determined in leaf and cotyledon samples of both albino and WT seedlings. Albino seedlings showed reduced growth. They also had lower chlorophyll and protein content in foliar tissues than WT seedlings, in addition to lower concentrations of lipids and carbohydrates stored in cotyledons. The chloroplasts of albino seedlings were poorly developed, with an undefined internal membrane system and the presence of plastoglobules. Wild-type seedlings had a uniseriate and hypoestomatic epidermis. The mesophyll was dorsiventral, consisting of a layer of palisade parenchyma and two to four layers of spongy parenchyma. In albino seedlings, the spongy parenchyma was compact, with few intercellular spaces, and the thickness of the mesophyll was larger, resulting in increased thickness of the leaf blade. Albino seedlings had higher stomatal density and number of pavement cells, although the stomata had smaller dimensions. In addition to the partial loss of chlorophylls, albino D. regia showed changes at physiological and structural levels, demonstrating the crucial nature of photosynthetic pigments during the development and differentiation of plant leaf tissues/cells.
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Affiliation(s)
- L A S Silva
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
| | - V F Sampaio
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
| | - L C S Barbosa
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
| | - M Machado
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
| | - D N A Flores-Borges
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - J F Sales
- Instituto Federal Goiano de Educação, Ciência e Tecnologia, Rio Verde, Brazil
| | - D C de Oliveira
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - J L S Mayer
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - V C Kuster
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
| | - D I Rocha
- Instituto de Ciências Biológicas, Universidade Federal de Jataí, Jataí, Brazil
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8
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Zhang X, Mei X, Wang Y, Huang G, Feng F, Liu X, Guo R, Gu F, Hu X, Yang Z, Zhong X, Li Y. Stomatal conductance bears no correlation with transpiration rate in wheat during their diurnal variation under high air humidity. PeerJ 2020; 8:e8927. [PMID: 32391197 PMCID: PMC7199760 DOI: 10.7717/peerj.8927] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 03/17/2020] [Indexed: 11/20/2022] Open
Abstract
A good understanding of the response of photosynthesis rate (P N) and transpiration rate (Tr) to stomatal alteration during the diurnal variations is important to cumulative photosynthetic production and water loss of crops. Six wheat genotypes were studied for 2 years with pot cultivation in rain-shelter. Among different genotypes, stomatal conductance (g s) was significantly correlated with both P N and Tr. But for each genotype, though g s was significantly correlated with P N regardless of relative air humidity (RH) status and it was also significantly correlated with Tr under lower RH (LRH, 15.4%) and moderate RH (MRH, 28.3%), it was not correlated with Tr under higher RH (HRH, 36.7%) during the diurnal changes. The conditional correlation between g s and Tr of wheat evoked new thinking on the relationships among g s, P N and Tr. Path analysis was further carried out to clarify the correlations of g s with the four atmospheric factors, that of Tr with g s and the four factors and the direct and indirect effects of the factors, during their diurnal dynamic variation. The effects of these factors on g s or Tr were related to RH. All the four factors had a much higher correlation with g s under HRH than that under LRH and MRH. Air temperature (T) had a rather higher direct effect than RH and photosynthetically active radiation (PAR). Also, the other factors had a much higher indirect effect on g s through vapor pressure deficit (VPD) and T. Transpiration rate was highly correlated with g s under LRH and MRH, with g s having a higher direct effect on it. In comparison, Tr was not correlated with g s under HRH but highly correlated with the atmospheric factors, with T, RH, and PAR having a higher indirect effect through VPD.
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Affiliation(s)
- Xinying Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Xurong Mei
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Yajing Wang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Guirong Huang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Fu Feng
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Xiaoying Liu
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Rui Guo
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Fengxue Gu
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Xin Hu
- Institute of Wheat Research, Shangqiu Academy of Agriculture and Forestry Sciences, Shangqiu, China
| | - Ziguang Yang
- Luoyang Academy of Agriculture and Forestry, Luoyang, China
| | - Xiuli Zhong
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
| | - Yuzhong Li
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
- State Engineering Laboratory of Efficient Water Use and Disaster Mitigation for Crops, Beijing, China
- Key Laboratory for Dryland Agriculture of Ministry of Agriculture, Beijing, China
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9
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Matthews JSA, Vialet-Chabrand S, Lawson T. Role of blue and red light in stomatal dynamic behaviour. J Exp Bot 2020; 71:2253-2269. [PMID: 31872212 PMCID: PMC7134916 DOI: 10.1093/jxb/erz563] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 12/19/2019] [Indexed: 05/20/2023]
Abstract
Plants experience changes in light intensity and quality due to variations in solar angle and shading from clouds and overlapping leaves. Stomatal opening to increasing irradiance is often an order of magnitude slower than photosynthetic responses, which can result in CO2 diffusional limitations on leaf photosynthesis, as well as unnecessary water loss when stomata continue to open after photosynthesis has reached saturation. Stomatal opening to light is driven by two distinct pathways; the 'red' or photosynthetic response that occurs at high fluence rates and saturates with photosynthesis, and is thought to be the main mechanism that coordinates stomatal behaviour with photosynthesis; and the guard cell-specific 'blue' light response that saturates at low fluence rates, and is often considered independent of photosynthesis, and important for early morning stomatal opening. Here we review the literature on these complicated signal transduction pathways and osmoregulatory processes in guard cells that are influenced by the light environment. We discuss the possibility of tuning the sensitivity and magnitude of stomatal response to blue light which potentially represents a novel target to develop ideotypes with the 'ideal' balance between carbon gain, evaporative cooling, and maintenance of hydraulic status that is crucial for maximizing crop performance and productivity.
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Affiliation(s)
- Jack S A Matthews
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, UK
| | | | - Tracy Lawson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, UK
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10
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Zhu M, Geng S, Chakravorty D, Guan Q, Chen S, Assmann SM. Metabolomics of red-light-induced stomatal opening in Arabidopsis thaliana: Coupling with abscisic acid and jasmonic acid metabolism. Plant J 2020; 101:1331-1348. [PMID: 31677315 DOI: 10.1111/tpj.14594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 09/20/2019] [Accepted: 09/30/2019] [Indexed: 06/10/2023]
Abstract
Environmental stimuli-triggered stomatal movement is a key physiological process that regulates CO2 uptake and water loss in plants. Stomata are defined by pairs of guard cells that perceive and transduce external signals, leading to cellular volume changes and consequent stomatal aperture change. Within the visible light spectrum, red light induces stomatal opening in intact leaves. However, there has been debate regarding the extent to which red-light-induced stomatal opening arises from direct guard cell sensing of red light versus indirect responses as a result of red light influences on mesophyll photosynthesis. Here we identify conditions that result in red-light-stimulated stomatal opening in isolated epidermal peels and enlargement of protoplasts, firmly establishing a direct guard cell response to red light. We then employ metabolomics workflows utilizing gas chromatography mass spectrometry and liquid chromatography mass spectrometry for metabolite profiling and identification of Arabidopsis guard cell metabolic signatures in response to red light in the absence of the mesophyll. We quantified 223 metabolites in Arabidopsis guard cells, with 104 found to be red light responsive. These red-light-modulated metabolites participate in the tricarboxylic acid cycle, carbon balance, phytohormone biosynthesis and redox homeostasis. We next analyzed selected Arabidopsis mutants, and discovered that stomatal opening response to red light is correlated with a decrease in guard cell abscisic acid content and an increase in jasmonic acid content. The red-light-modulated guard cell metabolome reported here provides fundamental information concerning autonomous red light signaling pathways in guard cells.
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Affiliation(s)
- Mengmeng Zhu
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Sisi Geng
- The Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, 32610, USA
| | - David Chakravorty
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Qijie Guan
- Department of Biology, Genetics Institute, University of Florida, Gainesville, FL, 32610, USA
| | - Sixue Chen
- The Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, 32610, USA
- Department of Biology, Genetics Institute, University of Florida, Gainesville, FL, 32610, USA
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, 32610, USA
| | - Sarah M Assmann
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
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11
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Brodribb TJ, Sussmilch F, McAdam SAM. From reproduction to production, stomata are the master regulators. Plant J 2020; 101:756-767. [PMID: 31596990 DOI: 10.1111/tpj.14561] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/14/2019] [Accepted: 10/03/2019] [Indexed: 05/22/2023]
Abstract
The best predictor of leaf level photosynthetic rate is the porosity of the leaf surface, as determined by the number and aperture of stomata on the leaf. This remarkable correlation between stomatal porosity (or diffusive conductance to water vapour gs ) and CO2 assimilation rate (A) applies to all major lineages of vascular plants (Figure 1) and is sufficiently predictable that it provides the basis for the model most widely used to predict water and CO2 fluxes from leaves and canopies. Yet the Ball-Berry formulation is only a phenomenological approximation that captures the emergent character of stomatal behaviour. Progressing to a more mechanistic prediction of plant gas exchange is challenging because of the diversity of biological components regulating stomatal action. These processes are the product of more than 400 million years of co-evolution between stomatal, vascular and photosynthetic tissues. Both molecular and structural components link the abiotic world of the whole plant with the turgor pressure of the epidermis and guard cells, which ultimately determine stomatal pore size and porosity to water and CO2 exchange (New Phytol., 168, 2005, 275). In this review we seek to simplify stomatal behaviour by using an evolutionary perspective to understand the principal selective pressures involved in stomatal evolution, thus identifying the primary regulators of stomatal aperture. We start by considering the adaptive process that has locked together the regulation of water and carbon fluxes in vascular plants, finally examining specific evidence for evolution in the proteins responsible for regulating guard cell turgor.
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Affiliation(s)
- Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Frances Sussmilch
- Institute for Molecular Plant Physiology and Biophysics, University of Wurzburg, Wuerzburg, Bavaria, Germany
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, USA
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Zhang J, De-Oliveira-Ceciliato P, Takahashi Y, Schulze S, Dubeaux G, Hauser F, Azoulay-Shemer T, Tõldsepp K, Kollist H, Rappel WJ, Schroeder JI. Insights into the Molecular Mechanisms of CO 2-Mediated Regulation of Stomatal Movements. Curr Biol 2019; 28:R1356-R1363. [PMID: 30513335 DOI: 10.1016/j.cub.2018.10.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Plants must continually balance the influx of CO2 for photosynthesis against the loss of water vapor through stomatal pores in their leaves. This balance can be achieved by controlling the aperture of the stomatal pores in response to several environmental stimuli. Elevation in atmospheric [CO2] induces stomatal closure and further impacts leaf temperatures, plant growth and water-use efficiency, and global crop productivity. Here, we review recent advances in understanding CO2-perception mechanisms and CO2-mediated signal transduction in the regulation of stomatal movements, and we explore how these mechanisms are integrated with other signaling pathways in guard cells.
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Affiliation(s)
- Jingbo Zhang
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Paulo De-Oliveira-Ceciliato
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Yohei Takahashi
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Sebastian Schulze
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Guillaume Dubeaux
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Felix Hauser
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Tamar Azoulay-Shemer
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA
| | - Kadri Tõldsepp
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Hannes Kollist
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Wouter-Jan Rappel
- Physics Department, University of California San Diego, La Jolla, CA 92093, USA
| | - Julian I Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093, USA.
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Zhang Z, Liu Z, Song H, Chen M, Cheng S. Protective Role of Leaf Variegation in Pittosporum tobira under Low Temperature: Insights into the Physio-Biochemical and Molecular Mechanisms. Int J Mol Sci 2019; 20:E4857. [PMID: 31574927 DOI: 10.3390/ijms20194857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 09/20/2019] [Accepted: 09/21/2019] [Indexed: 01/17/2023] Open
Abstract
Leaf variegation has been demonstrated to have adaptive functions such as cold tolerance. Pittosporum tobira is an ornamental plant with natural leaf variegated cultivars grown in temperate regions. Herein, we investigated the role of leaf variegation in low temperature responses by comparing variegated “Variegatum” and non-variegated “Green Pittosporum” cultivars. We found that leaf variegation is associated with impaired chloroplast development in the yellow sector, reduced chlorophyll content, strong accumulation of carotenoids and high levels of ROS. However, the photosynthetic efficiency was not obviously impaired in the variegated leaves. Also, leaf variegation plays low temperature protective function since “Variegatum” displayed strong and efficient ROS-scavenging enzymatic systems to buffer cold (10 °C)-induced damages. Transcriptome analysis under cold conditions revealed 309 differentially expressed genes between both cultivars. Distinctly, the strong cold response observed in “Variegatum” was essentially attributed to the up-regulation of HSP70/90 genes involved in cellular homeostasis; up-regulation of POD genes responsible for cell detoxification and up-regulation of FAD2 genes and subsequent down-regulation of GDSL genes leading to high accumulation of polyunsaturated fatty acids for cell membrane fluidity. Overall, our results indicated that leaf variegation is associated with changes in physiological, biochemical and molecular components playing low temperature protective function in P. tobira.
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Shelef O, Summerfield L, Lev-Yadun S, Villamarin-Cortez S, Sadeh R, Herrmann I, Rachmilevitch S. Thermal Benefits From White Variegation of Silybum marianum Leaves. Front Plant Sci 2019; 10:688. [PMID: 31178888 PMCID: PMC6543541 DOI: 10.3389/fpls.2019.00688] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 05/07/2019] [Indexed: 05/24/2023]
Abstract
Leaves of the spiny winter annual Silybum marianum express white patches (variegation) that can cover significant surface areas, the outcome of air spaces formed between the epidermis and the green chlorenchyma. We asked: (1) what characterizes the white patches in S. marianum and what differs them from green patches? (2) Do white patches differ from green patches in photosynthetic efficiency under lower temperatures? We predicted that the air spaces in white patches have physiological benefits, elevating photosynthetic rates under low temperatures. To test our hypotheses we used both a variegated wild type and entirely green mutants. We grew the plants under moderate temperatures (20°C/10°C d/n) and compared them to plants grown under lower temperatures (15°C/5°C d/n). The developed plants were exposed to different temperatures for 1 h and their photosynthetic activity was measured. In addition, we compared in green vs. white patches, the reflectance spectra, patch structure, chlorophyll and dehydrin content, stomatal structure, plant growth, and leaf temperature. White patches were not significantly different from green patches in their biochemistry and photosynthesis. However, under lower temperatures, variegated wild-type leaves were significantly warmer than all-green mutants - possible explanations for that are discussed These findings support our hypothesis, that white variegation of S. marianum leaves has a physiological role, elevating leaf temperature during cold winter days.
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Affiliation(s)
- Oren Shelef
- Department of Natural Resources, Institute of Plant Sciences, Agricultural Research Organization, Rishon LeZion, Israel
| | - Liron Summerfield
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Simcha Lev-Yadun
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa–Oranim, Tivon, Israel
| | | | - Roy Sadeh
- 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 Jerusalem, Rehovot, Israel
| | - Ittai Herrmann
- 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 Jerusalem, Rehovot, Israel
| | - Shimon Rachmilevitch
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel
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Iwai S, Ogata S, Yamada N, Onjo M, Sonoike K, Shimazaki K. Guard cell photosynthesis is crucial in abscisic acid-induced stomatal closure. Plant Direct 2019; 3:e00137. [PMID: 31245777 PMCID: PMC6589527 DOI: 10.1002/pld3.137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 03/29/2019] [Accepted: 04/06/2019] [Indexed: 05/03/2023]
Abstract
Reactive oxygen species (ROS) are ubiquitous signaling molecules involved in diverse physiological processes, including stomatal closure. Photosynthetic electron transport (PET) is the main source of ROS generation in plants, but whether it functions in guard cell signaling remains unclear. Here, we assessed whether PET functions in abscisic acid (ABA) signaling in guard cells. ABA-elicited ROS were localized to guard cell chloroplasts in Arabidopsis thaliana, Commelina benghalensis, and Vicia faba in the light and abolished by the PET inhibitors 3-(3, 4-dichlorophenyl)-1, 1-dimethylurea and 2, 5-dibromo-3-methyl-6-isopropyl-p-benzoquinone. These inhibitors reduced ABA-induced stomatal closure in all three species, as well as in the NADPH oxidase-lacking mutant atrboh D/F. However, an NADPH oxidase inhibitor did not fully eliminate ABA-induced ROS in the chloroplasts, and ABA-induced ROS were still observed in the guard cell chloroplasts of atrboh D/F. This study demonstrates that ROS generated through PET act as signaling molecules in ABA-induced stomatal closure and that this occurs in concert with ROS derived through NADPH oxidase.
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Affiliation(s)
- Sumio Iwai
- Department of Horticultural ScienceFaculty of AgricultureKagoshima UniversityKagoshimaJapan
- Kagoshima University Experimental FarmKagoshimaJapan
| | - Sho Ogata
- Department of Horticultural ScienceFaculty of AgricultureKagoshima UniversityKagoshimaJapan
| | - Naotaka Yamada
- Department of Bioscience and BiotechnologyFaculty of AgricultureKyushu UniversityFukuokaJapan
| | - Michio Onjo
- Kagoshima University Experimental FarmKagoshimaJapan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and SciencesWaseda UniversityTokyoJapan
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Abstract
SIGNIFICANCE Stomata sense the intercellular carbon dioxide (CO2) concentration (Ci) and water availability under changing environmental conditions and adjust their apertures to maintain optimal cellular conditions for photosynthesis. Stomatal movements are regulated by a complex network of signaling cascades where reactive oxygen species (ROS) play a key role as signaling molecules. Recent Advances: Recent research has uncovered several new signaling components involved in CO2- and abscisic acid-triggered guard cell signaling pathways. In addition, we are beginning to understand the complex interactions between different signaling pathways. CRITICAL ISSUES Plants close their stomata in reaction to stress conditions, such as drought, and the subsequent decrease in Ci leads to ROS production through photorespiration and over-reduction of the chloroplast electron transport chain. This reduces plant growth and thus drought may cause severe yield losses for agriculture especially in arid areas. FUTURE DIRECTIONS The focus of future research should be drawn toward understanding the interplay between various signaling pathways and how ROS, redox, and hormonal balance changes in space and time. Translating this knowledge from model species to crop plants will help in the development of new drought-resistant crop species with high yields.
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Affiliation(s)
- Sanna Ehonen
- 1 Division of Plant Biology, Department of Biosciences, University of Helsinki, Helsinki, Finland.,2 Department of Forest Sciences, University of Helsinki, Helsinki, Finland
| | | | - Hannes Kollist
- 3 Institute of Technology, University of Tartu, Tartu, Estonia
| | - Jaakko Kangasjärvi
- 1 Division of Plant Biology, Department of Biosciences, University of Helsinki, Helsinki, Finland
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Wang C, Zhang J, Wu J, Brodsky D, Schroeder JI. Cytosolic malate and oxaloacetate activate S-type anion channels in Arabidopsis guard cells. New Phytol 2018; 220:178-186. [PMID: 29971803 PMCID: PMC6115288 DOI: 10.1111/nph.15292] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 05/21/2018] [Indexed: 05/10/2023]
Abstract
Intracellular malate-starch interconversion plays an important role in stomatal movements. We investigated whether malate or oxaloacetate from the cytosolic membrane side regulate anion channels in the plasma membrane of Arabidopsis thaliana guard cells. Physiological concentrations of cytosolic malate have been reported in the range of 0.4-3 mM in leaf cells. Guard cell patch clamp and two-electrode oocyte voltage-clamp experiments were pursued. We show that a concentration of 1 mM cytosolic malate greatly activates S-type anion channels in Arabidopsis thaliana guard cells. Interestingly, 1 mM cytosolic oxaloacetate also activates S-type anion channels. Malate activation was abrogated at 10 mM malate and in SLAC1 anion channel mutant alleles. Interestingly, malate activation of S-type anion currents was disrupted at below resting cytosolic-free calcium concentrations ([Ca2+ ]cyt ), suggesting a key role for basal [Ca2+ ]cyt signaling. Cytosolic malate was not able to directly activate or enhance SLAC1-mediated anion currents in Xenopus oocytes, whereas in positive controls, cytosolic NaHCO3 enhanced SLAC1 activity, suggesting that malate may not directly modulate SLAC1. Cytosolic malate activation of S-type anion currents was impaired in ost1 and in cpk5/6/11/23 quadruple mutant guard cells. Together these findings show that these cytosolic organic anions function in guard cell 'plasma membrane' ion channel regulation.
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Affiliation(s)
- Cun Wang
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
- College of Life Sciences & State Key Laboratory of Crop Stress Biology in Arid Areas Northwest A&F University, Yangling, Shaanxi, China
| | - Jingbo Zhang
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
| | - Juyou Wu
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
| | - Dennis Brodsky
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
| | - Julian I. Schroeder
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
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Negi J, Munemasa S, Song B, Tadakuma R, Fujita M, Azoulay-Shemer T, Engineer CB, Kusumi K, Nishida I, Schroeder JI, Iba K. Eukaryotic lipid metabolic pathway is essential for functional chloroplasts and CO 2 and light responses in Arabidopsis guard cells. Proc Natl Acad Sci U S A 2018; 115:9038-9043. [PMID: 30127035 PMCID: PMC6130404 DOI: 10.1073/pnas.1810458115] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Stomatal guard cells develop unique chloroplasts in land plant species. However, the developmental mechanisms and function of chloroplasts in guard cells remain unclear. In seed plants, chloroplast membrane lipids are synthesized via two pathways: the prokaryotic and eukaryotic pathways. Here we report the central contribution of endoplasmic reticulum (ER)-derived chloroplast lipids, which are synthesized through the eukaryotic lipid metabolic pathway, in the development of functional guard cell chloroplasts. We gained insight into this pathway by isolating and examining an Arabidopsis mutant, gles1 (green less stomata 1), which had achlorophyllous stomatal guard cells and impaired stomatal responses to CO2 and light. The GLES1 gene encodes a small glycine-rich protein, which is a putative regulatory component of the trigalactosyldiacylglycerol (TGD) protein complex that mediates ER-to-chloroplast lipid transport via the eukaryotic pathway. Lipidomic analysis revealed that in the wild type, the prokaryotic pathway is dysfunctional, specifically in guard cells, whereas in gles1 guard cells, the eukaryotic pathway is also abrogated. CO2-induced stomatal closing and activation of guard cell S-type anion channels that drive stomatal closure were disrupted in gles1 guard cells. In conclusion, the eukaryotic lipid pathway plays an essential role in the development of a sensing/signaling machinery for CO2 and light in guard cell chloroplasts.
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Affiliation(s)
- Juntaro Negi
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan;
| | - Shintaro Munemasa
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Boseok Song
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan
| | - Ryosuke Tadakuma
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan
| | - Mayumi Fujita
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan
| | - Tamar Azoulay-Shemer
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Cawas B Engineer
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Kensuke Kusumi
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan
| | - Ikuo Nishida
- Graduate School of Science and Engineering, Saitama University, 338-8570 Saitama, Japan
| | - Julian I Schroeder
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Koh Iba
- Department of Biology, Faculty of Science, Kyushu University, 819-0395 Fukuoka, Japan;
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Voss LJ, McAdam SAM, Knoblauch M, Rathje JM, Brodribb T, Hedrich R, Roelfsema MRG. Guard cells in fern stomata are connected by plasmodesmata, but control cytosolic Ca 2+ levels autonomously. New Phytol 2018; 219:206-215. [PMID: 29655174 DOI: 10.1111/nph.15153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 03/06/2018] [Indexed: 05/10/2023]
Abstract
Recent studies have revealed that some responses of fern stomata to environmental signals differ from those of their relatives in seed plants. However, it is unknown whether the biophysical properties of guard cells differ fundamentally between species of both clades. Intracellular micro-electrodes and the fluorescent Ca2+ reporter FURA2 were used to study voltage-dependent cation channels and Ca2+ signals in guard cells of the ferns Polypodium vulgare and Asplenium scolopendrium. Voltage clamp experiments with fern guard cells revealed similar properties of voltage-dependent K+ channels as found in seed plants. However, fluorescent dyes moved within the fern stomata, from one guard cell to the other, which does not occur in most seed plants. Despite the presence of plasmodesmata, which interconnect fern guard cells, Ca2+ signals could be elicited in each of the cells individually. Based on the common properties of voltage-dependent channels in ferns and seed plants, it is likely that these key transport proteins are conserved in vascular plants. However, the symplastic connections between fern guard cells in mature stomata indicate that the biophysical mechanisms that control stomatal movements differ between ferns and seed plants.
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Affiliation(s)
- Lena J Voss
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082, Würzburg, Germany
| | - Scott A M McAdam
- School of Biological Science, University of Tasmania, Hobart, TAS, 7001, Australia
- Botany and Plant Pathology, Purdue University, 915 West State Street, West Lafayette, IN, 47907, USA
| | - Michael Knoblauch
- School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA, 99164-4236, USA
| | - Jan M Rathje
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082, Würzburg, Germany
| | - Tim Brodribb
- School of Biological Science, University of Tasmania, Hobart, TAS, 7001, Australia
| | - Rainer Hedrich
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082, Würzburg, Germany
| | - M Rob G Roelfsema
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082, Würzburg, Germany
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Lawson T, Terashima I, Fujita T, Wang Y. Coordination Between Photosynthesis and Stomatal Behavior. The Leaf: A Platform for Performing Photosynthesis 2018. [DOI: 10.1007/978-3-319-93594-2_6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Daloso DM, Medeiros DB, Dos Anjos L, Yoshida T, Araújo WL, Fernie AR. Metabolism within the specialized guard cells of plants. New Phytol 2017; 216:1018-1033. [PMID: 28984366 DOI: 10.1111/nph.14823] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 08/21/2017] [Indexed: 05/21/2023]
Abstract
Contents 1018 I. 1018 II. 1019 III. 1022 IV. 1025 V. 1026 VI. 1029 1030 References 1030 SUMMARY: Stomata are leaf epidermal structures consisting of two guard cells surrounding a pore. Changes in the aperture of this pore regulate plant water-use efficiency, defined as gain of C by photosynthesis per leaf water transpired. Stomatal aperture is actively regulated by reversible changes in guard cell osmolyte content. Despite the fact that guard cells can photosynthesize on their own, the accumulation of mesophyll-derived metabolites can seemingly act as signals which contribute to the regulation of stomatal movement. It has been shown that malate can act as a signalling molecule and a counter-ion of potassium, a well-established osmolyte that accumulates in the vacuole of guard cells during stomatal opening. By contrast, their efflux from guard cells is an important mechanism during stomatal closure. It has been hypothesized that the breakdown of starch, sucrose and lipids is an important mechanism during stomatal opening, which may be related to ATP production through glycolysis and mitochondrial metabolism, and/or accumulation of osmolytes such as sugars and malate. However, experimental evidence supporting this theory is lacking. Here we highlight the particularities of guard cell metabolism and discuss this in the context of the guard cells themselves and their interaction with the mesophyll cells.
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Affiliation(s)
- Danilo M Daloso
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, Ceará, 60451-970, Brasil
| | - David B Medeiros
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, Potsdam-Golm, 14476, Germany
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brasil
| | - Letícia Dos Anjos
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, Ceará, 60451-970, Brasil
| | - Takuya Yoshida
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, Potsdam-Golm, 14476, Germany
| | - Wagner L Araújo
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brasil
| | - Alisdair R Fernie
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, Potsdam-Golm, 14476, Germany
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22
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Hedrich R, Geiger D. Biology of SLAC1-type anion channels - from nutrient uptake to stomatal closure. New Phytol 2017; 216:46-61. [PMID: 28722226 DOI: 10.1111/nph.14685] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/25/2017] [Indexed: 05/22/2023]
Abstract
Contents 46 I. 46 II. 47 III. 50 IV. 53 V. 56 VI. 57 58 58 References 58 SUMMARY: Stomatal guard cells control leaf CO2 intake and concomitant water loss to the atmosphere. When photosynthetic CO2 assimilation is limited and the ratio of CO2 intake to transpiration becomes suboptimal, guard cells, sensing the rise in CO2 concentration in the substomatal cavity, deflate and the stomata close. Screens for mutants that do not close in response to experimentally imposed high CO2 atmospheres identified the guard cell-expressed Slowly activating anion channel, SLAC1, as the key player in the regulation of stomatal closure. SLAC1 evolved, though, before the emergence of guard cells. In Arabidopsis, SLAC1 is the founder member of a family of anion channels, which comprises four homologues. SLAC1 and SLAH3 mediate chloride and nitrate transport in guard cells, while SLAH1, SLAH2 and SLAH3 are engaged in root nitrate and chloride acquisition, and anion translocation to the shoot. The signal transduction pathways involved in CO2 , water stress and nutrient-sensing activate SLAC/SLAH via distinct protein kinase/phosphatase pairs. In this review, we discuss the role that SLAC/SLAH channels play in guard cell closure, on the one hand, and in the root-shoot continuum on the other, along with the molecular basis of the channels' anion selectivity and gating.
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Affiliation(s)
- Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, Biocenter, University of Wuerzburg, Wuerzburg, 97082, Germany
| | - Dietmar Geiger
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, Biocenter, University of Wuerzburg, Wuerzburg, 97082, Germany
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Ruggiero A, Punzo P, Landi S, Costa A, Van Oosten M, Grillo S. Improving Plant Water Use Efficiency through Molecular Genetics. Horticulturae 2017; 3:31. [DOI: 10.3390/horticulturae3020031] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zhang Q, Liu M, Ruan J. Metabolomics analysis reveals the metabolic and functional roles of flavonoids in light-sensitive tea leaves. BMC Plant Biol 2017; 17:64. [PMID: 28320327 PMCID: PMC5359985 DOI: 10.1186/s12870-017-1012-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 03/09/2017] [Indexed: 05/19/2023]
Abstract
BACKGROUND As the predominant secondary metabolic pathway in tea plants, flavonoid biosynthesis increases with increasing temperature and illumination. However, the concentration of most flavonoids decreases greatly in light-sensitive tea leaves when they are exposed to light, which further improves tea quality. To reveal the metabolism and potential functions of flavonoids in tea leaves, a natural light-sensitive tea mutant (Huangjinya) cultivated under different light conditions was subjected to metabolomics analysis. RESULTS The results showed that chlorotic tea leaves accumulated large amounts of flavonoids with ortho-dihydroxylated B-rings (e.g., catechin gallate, quercetin and its glycosides etc.), whereas total flavonoids (e.g., myricetrin glycoside, epigallocatechin gallate etc.) were considerably reduced, suggesting that the flavonoid components generated from different metabolic branches played different roles in tea leaves. Furthermore, the intracellular localization of flavonoids and the expression pattern of genes involved in secondary metabolic pathways indicate a potential photoprotective function of dihydroxylated flavonoids in light-sensitive tea leaves. CONCLUSIONS Our results suggest that reactive oxygen species (ROS) scavenging and the antioxidation effects of flavonoids help chlorotic tea plants survive under high light stress, providing new evidence to clarify the functional roles of flavonoids, which accumulate to high levels in tea plants. Moreover, flavonoids with ortho-dihydroxylated B-rings played a greater role in photo-protection to improve the acclimatization of tea plants.
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Affiliation(s)
- Qunfeng Zhang
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310058 China
- Key Laboratory for Plant Biology and Resource Application of Tea, the Ministry of Agriculture, South Meiling Road 9, Hangzhou, Zhejiang 310008 China
| | - Meiya Liu
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310058 China
- Key Laboratory for Plant Biology and Resource Application of Tea, the Ministry of Agriculture, South Meiling Road 9, Hangzhou, Zhejiang 310008 China
| | - Jianyun Ruan
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310058 China
- Key Laboratory for Plant Biology and Resource Application of Tea, the Ministry of Agriculture, South Meiling Road 9, Hangzhou, Zhejiang 310008 China
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Vidović M, Morina F, Prokić L, Milić-Komić S, Živanović B, Jovanović SV. Antioxidative response in variegated Pelargonium zonale leaves and generation of extracellular H 2O 2 in (peri)vascular tissue induced by sunlight and paraquat. J Plant Physiol 2016; 206:25-39. [PMID: 27688091 DOI: 10.1016/j.jplph.2016.07.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 07/19/2016] [Accepted: 07/20/2016] [Indexed: 06/06/2023]
Abstract
In this study we exposed variegated leaves of Pelargonium zonale to strong sunlight (>1100μmolm-2s-1 of photosynthetically active radiation) with and without paraquat (Pq), with the aim to elucidate the mechanisms of H2O2 regulation in green and white tissues with respect to the photosynthetically-dependent generation of reactive oxygen species (ROS). Sunlight induced marked accumulation of H2O2 in the apoplast of vascular and (peri)vascular tissues only in green sectors. This effect was enhanced by the addition of Pq. In the presence of diphenyl iodide, an NADPH oxidase inhibitor, H2O2 accumulation was abolished. Distinct light-induced responses were observed: in photosynthetic cells, sunlight rapidly provoked ascorbate (Asc) biosynthesis and an increase of glutathione reductase (GR) and catalase activities, while in non-photosynthetic cells, early up-regulation of soluble ascorbate peroxidase, dehydroascorbate reductase (DHAR) and GR activities was observed. Paraquat addition stimulated DHAR and GR activities in green sectors, while in white sectors activities of monodehydroascorbate reductase, DHAR and class III peroxidases, as well as Asc content rapidly increased. Differential antioxidative responses in the two tissues in the frame of their contrasting metabolisms, and the possible role of (peri)vascular H2O2 in signaling were discussed.
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Affiliation(s)
- Marija Vidović
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
| | - Filis Morina
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
| | - Ljiljana Prokić
- Faculty of Agriculture, University of Belgrade, Nemanjina 6, 11080 Belgrade, Serbia.
| | - Sonja Milić-Komić
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
| | - Bojana Živanović
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
| | - Sonja Veljović Jovanović
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
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Hashimoto-Sugimoto M, Negi J, Monda K, Higaki T, Isogai Y, Nakano T, Hasezawa S, Iba K. Dominant and recessive mutations in the Raf-like kinase HT1 gene completely disrupt stomatal responses to CO2 in Arabidopsis. J Exp Bot 2016; 67:3251-61. [PMID: 27034327 PMCID: PMC4892718 DOI: 10.1093/jxb/erw134] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
HT1 (HIGH LEAF TEMPERATURE 1) is the first component associated with changes in stomatal aperture in response to CO2 to be isolated by forward genetic screening. The HT1 gene encodes a protein kinase expressed mainly in guard cells. The loss-of-function ht1-1 and ht1-2 mutants in Arabidopsis thaliana have CO2-hypersensitive stomatal closure with concomitant reductions in their kinase activities in vitro In addition to these mutants, in this study we isolate or obtaine five new ht1 alleles (ht1-3, ht1-4, ht1-5, ht1-6, and ht1-7). Among the mutants, only ht1-3 has a dominant mutant phenotype and has widely opened stomata due to CO2 insensitivity. The ht1-3 mutant has a missense mutation affecting a non-conserved residue (R102K), whereas the other six recessive mutants have mutations in highly conserved residues in the catalytic domains required for kinase activity. We found that the dominant mutation does not affect the expression of HT1 or the ability to phosphorylate casein, a universal kinase substrate, but it does affect autophosphorylation activity in vitro A 3D structural model of HT1 also shows that the R102 residue protrudes from the surface of the kinase, implying a role for the formation of oligomers and/or interaction with its targets. We demonstrate that both the loss-of-function and gain-of-function ht1 mutants have completely disrupted CO2 responses, although they have normal responses to ABA. Furthermore, light-induced stomatal opening is smaller in ht1-3 and much smaller in ht1-2 Taken together, these results indicate that HT1 is a critical regulator for CO2 signaling and is partially involved in the light-induced stomatal opening pathway.
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Affiliation(s)
| | - Juntaro Negi
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Keina Monda
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Takumi Higaki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha Kashiwa, Chiba 277-8562, Japan
| | - Yasuhiro Isogai
- Department of Biotechnology, Faculty of Engineering, Biotechnology Research Center, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Toshiaki Nakano
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Seiichiro Hasezawa
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha Kashiwa, Chiba 277-8562, Japan
| | - Koh Iba
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan.
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Wang WH, He EM, Chen J, Guo Y, Chen J, Liu X, Zheng HL. The reduced state of the plastoquinone pool is required for chloroplast-mediated stomatal closure in response to calcium stimulation. Plant J 2016; 86:132-44. [PMID: 26945669 DOI: 10.1111/tpj.13154] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/16/2016] [Accepted: 02/22/2016] [Indexed: 05/12/2023]
Abstract
Besides their participation in photosynthesis, leaf chloroplasts function in plant responses to stimuli, yet how they direct stimulus-induced stomatal movement remains elusive. Here, we showed that over-reduction of the plastoquinone (PQ) pool by dibromothymoquinone (DBMIB) was closely associated with stomatal closure in plants which required chloroplastic H2O2 generation in the mesophyll. External application of H2 O2 reduced the PQ pool, whereas the cell-permeable reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) reversed the DBMIB-induced over-reduction of the PQ pool and stomatal closure. Mesophyll chloroplasts are key players of extracellular Ca(2+) (Ca(2+)o)-induced stomatal closure, but when treated with either 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) or NAC they failed to facilitate Ca(2+)o-induced stomatal closure due to the inhibition of chloroplastic H2 O2 synthesis in mesophyll. Similarly, the Arabidopsis electron transfer chain-related mutants npq4-1, stn7 and cas-1 exhibited diverse responses to Ca(2+)o or DBMIB. Transcriptome analysis also demonstrated that the PQ pool signaling pathway shared common responsive genes with the H2 O2 signaling pathway. These results implicated a mechanism for chloroplast-mediated stomatal closure involving the generation of mesophyll chloroplastic H2O2 based on the reduced state of the PQ pool, which is calcium-sensing receptor (CAS) and LHCII phosphorylation dependent.
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Affiliation(s)
- Wen-Hua Wang
- Fujian Key Laboratory of Subtropical Plant Physiology and Biochemistry, Fujian Institute of Subtropical Botany, Xiamen, Fujian, 361006, China
| | - En-Ming He
- Fujian Key Laboratory of Subtropical Plant Physiology and Biochemistry, Fujian Institute of Subtropical Botany, Xiamen, Fujian, 361006, China
| | - Juan Chen
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Ying Guo
- Fujian Key Laboratory of Subtropical Plant Physiology and Biochemistry, Fujian Institute of Subtropical Botany, Xiamen, Fujian, 361006, China
| | - Juan Chen
- Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361005, China
| | - Xiang Liu
- Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361005, China
| | - Hai-Lei Zheng
- Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361005, China
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Engineer CB, Hashimoto-Sugimoto M, Negi J, Israelsson-Nordström M, Azoulay-Shemer T, Rappel WJ, Iba K, Schroeder JI. CO2 Sensing and CO2 Regulation of Stomatal Conductance: Advances and Open Questions. Trends Plant Sci 2016; 21:16-30. [PMID: 26482956 PMCID: PMC4707055 DOI: 10.1016/j.tplants.2015.08.014] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/24/2015] [Accepted: 08/27/2015] [Indexed: 05/18/2023]
Abstract
Guard cells form epidermal stomatal gas-exchange valves in plants and regulate the aperture of stomatal pores in response to changes in the carbon dioxide (CO2) concentration ([CO2]) in leaves. Moreover, the development of stomata is repressed by elevated CO2 in diverse plant species. Evidence suggests that plants can sense [CO2] changes via guard cells and via mesophyll tissues in mediating stomatal movements. We review new discoveries and open questions on mechanisms mediating CO2-regulated stomatal movements and CO2 modulation of stomatal development, which together function in the CO2 regulation of stomatal conductance and gas exchange in plants. Research in this area is timely in light of the necessity of selecting and developing crop cultivars that perform better in a shifting climate.
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Affiliation(s)
- Cawas B Engineer
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Mimi Hashimoto-Sugimoto
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Juntaro Negi
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Maria Israelsson-Nordström
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden
| | - Tamar Azoulay-Shemer
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Wouter-Jan Rappel
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Koh Iba
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Julian I Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
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Matrosova A, Bogireddi H, Mateo-Peñas A, Hashimoto-Sugimoto M, Iba K, Schroeder JI, Israelsson-Nordström M. The HT1 protein kinase is essential for red light-induced stomatal opening and genetically interacts with OST1 in red light and CO2 -induced stomatal movement responses. New Phytol 2015; 208:1126-37. [PMID: 26192339 DOI: 10.1111/nph.13566] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/11/2015] [Indexed: 05/26/2023]
Abstract
The question of whether red light-induced stomatal opening is mediated by a photosynthesis-derived reduction in intercellular [CO2 ] (Ci ) remains controversial and genetic analyses are needed. The Arabidopsis thaliana protein kinase HIGH TEMPERATURE 1 (HT1) is a negative regulator of [CO2 ]-induced stomatal closing and ht1-2 mutant plants do not show stomatal opening to low [CO2 ]. The protein kinase mutant ost1-3 exhibits slowed stomatal responses to CO2 . The functions of HT1 and OPEN STOMATA 1 (OST1) to changes in red, blue light or [CO2 ] were analyzed. For comparison we assayed recessive ca1ca4 carbonic anhydrase double mutant plants, based on their slowed stomatal response to CO2 . Here, we report a strong impairment in ht1 in red light-induced stomatal opening whereas blue light was able to induce stomatal opening. The effects on photosynthetic performance in ht1 were restored when stomatal limitation of CO2 uptake, by control of [Ci ], was eliminated. HT1 was found to interact genetically with OST1 both during red light- and low [CO2 ]-induced stomatal opening. Analyses of ca1ca4 plants suggest that more than a low [Ci ]-dependent pathway may function in red light-induced stomatal opening. These results demonstrate that HT1 is essential for red light-induced stomatal opening and interacts genetically with OST1 during stomatal responses to red light and altered [CO2 ].
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Affiliation(s)
- Anastasia Matrosova
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Hanumakumar Bogireddi
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Alfonso Mateo-Peñas
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | | | - Koh Iba
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, 812-8581, Japan
| | - Julian I Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA, 92093-0116, USA
| | - Maria Israelsson-Nordström
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
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Córdoba J, Molina-Cano JL, Pérez P, Morcuende R, Moralejo M, Savé R, Martínez-Carrasco R. Photosynthesis-dependent/independent control of stomatal responses to CO2 in mutant barley with surplus electron transport capacity and reduced SLAH3 anion channel transcript. Plant Sci 2015; 239:15-25. [PMID: 26398787 DOI: 10.1016/j.plantsci.2015.07.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/17/2015] [Accepted: 07/13/2015] [Indexed: 05/03/2023]
Abstract
The mechanisms of stomatal sensitivity to CO2 are yet to be fully understood. The role of photosynthetic and non-photosynthetic factors in stomatal responses to CO2 was investigated in wild-type barley (Hordeum vulgare var. Graphic) and in a mutant (G132) with decreased photochemical and Rubisco capacities. The CO2 and DCMU responses of stomatal conductance (gs), gas exchange, chlorophyll fluorescence and levels of ATP, with a putative transcript for stomatal opening were analysed. G132 had greater gs than the wild-type, despite lower photosynthesis rates and higher intercellular CO2 concentrations (Ci). The mutant had Rubisco-limited photosynthesis at very high CO2 levels, and higher ATP contents than the wild-type. Stomatal sensitivity to CO2 under red light was lower in G132 than in the wild-type, both in photosynthesizing and DCMU-inhibited leaves. Under constant Ci and red light, stomatal sensitivity to DCMU inhibition was higher in G132. The levels of a SLAH3-like slow anion channel transcript, involved in stomatal closure, decreased sharply in G132. The results suggest that stomatal responses to CO2 depend partly on the balance of photosynthetic electron transport to carbon assimilation capacities, but are partially regulated by the CO2 signalling network. High gs can improve the adaptation to climate change in well-watered conditions.
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Affiliation(s)
- Javier Córdoba
- Institute of Natural Resources and Agrobiology of Salamanca, IRNASA-CSIC, Cordel de Merinas, 40, E-37008 Salamanca, Spain; IRTA (Institute for Food and Agricultural Research and Technology), Field Crops, Av. Alcalde Rovira i Roure, 191, E-25198 Lérida, Spain
| | - José-Luis Molina-Cano
- IRTA (Institute for Food and Agricultural Research and Technology), Field Crops, Av. Alcalde Rovira i Roure, 191, E-25198 Lérida, Spain
| | - Pilar Pérez
- Institute of Natural Resources and Agrobiology of Salamanca, IRNASA-CSIC, Cordel de Merinas, 40, E-37008 Salamanca, Spain
| | - Rosa Morcuende
- Institute of Natural Resources and Agrobiology of Salamanca, IRNASA-CSIC, Cordel de Merinas, 40, E-37008 Salamanca, Spain
| | - Marian Moralejo
- Universidad de Lleida, Av. Alcalde Rovira i Roure, 191, E-25198 Lérida, Spain
| | - Robert Savé
- IRTA, Environmental Horticulture, Torre Marimon, E-08140 Caldes de Montbui, Barcelona, Spain
| | - Rafael Martínez-Carrasco
- Institute of Natural Resources and Agrobiology of Salamanca, IRNASA-CSIC, Cordel de Merinas, 40, E-37008 Salamanca, Spain.
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Guzel Deger A, Scherzer S, Nuhkat M, Kedzierska J, Kollist H, Brosché M, Unyayar S, Boudsocq M, Hedrich R, Roelfsema MRG. Guard cell SLAC1-type anion channels mediate flagellin-induced stomatal closure. New Phytol 2015; 208:162-73. [PMID: 25932909 PMCID: PMC4949714 DOI: 10.1111/nph.13435] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/29/2015] [Indexed: 05/18/2023]
Abstract
During infection plants recognize microbe-associated molecular patterns (MAMPs), and this leads to stomatal closure. This study analyzes the molecular mechanisms underlying this MAMP response and its interrelation with ABA signaling. Stomata in intact Arabidopsis thaliana plants were stimulated with the bacterial MAMP flg22, or the stress hormone ABA, by using the noninvasive nanoinfusion technique. Intracellular double-barreled microelectrodes were applied to measure the activity of plasma membrane ion channels. Flg22 induced rapid stomatal closure and stimulated the SLAC1 and SLAH3 anion channels in guard cells. Loss of both channels resulted in cells that lacked flg22-induced anion channel activity and stomata that did not close in response to flg22 or ABA. Rapid flg22-dependent stomatal closure was impaired in plants that were flagellin receptor (FLS2)-deficient, as well as in the ost1-2 (Open Stomata 1) mutant, which lacks a key ABA-signaling protein kinase. By contrast, stomata of the ABA protein phosphatase mutant abi1-1 (ABscisic acid Insensitive 1) remained flg22-responsive. These data suggest that the initial steps in flg22 and ABA signaling are different, but that the pathways merge at the level of OST1 and lead to activation of SLAC1 and SLAH3 anion channels.
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Affiliation(s)
- Aysin Guzel Deger
- Molecular Plant Physiology and BiophysicsJulius‐von‐Sachs Institute for BiosciencesBiocenterUniversity of WürzburgJulius‐von‐Sachs‐Platz 2D‐97082WürzburgGermany
- Faculty of Science and LettersDepartment of BiologyUniversity of Mersin33343MersinTurkey
| | - Sönke Scherzer
- Molecular Plant Physiology and BiophysicsJulius‐von‐Sachs Institute for BiosciencesBiocenterUniversity of WürzburgJulius‐von‐Sachs‐Platz 2D‐97082WürzburgGermany
| | - Maris Nuhkat
- Institute of TechnologyUniversity of TartuNooruse 1Tartu50411Estonia
| | - Justyna Kedzierska
- Molecular Plant Physiology and BiophysicsJulius‐von‐Sachs Institute for BiosciencesBiocenterUniversity of WürzburgJulius‐von‐Sachs‐Platz 2D‐97082WürzburgGermany
| | - Hannes Kollist
- Institute of TechnologyUniversity of TartuNooruse 1Tartu50411Estonia
| | - Mikael Brosché
- Institute of TechnologyUniversity of TartuNooruse 1Tartu50411Estonia
- Division of Plant BiologyDepartment of BiosciencesUniversity of HelsinkiPO box 65FI‐00014HelsinkiFinland
| | - Serpil Unyayar
- Faculty of Science and LettersDepartment of BiologyUniversity of Mersin33343MersinTurkey
| | - Marie Boudsocq
- Institute of Plant Sciences Paris‐SaclayUMR9213/UMR1403 CNRS‐INRA‐Université Paris Sud‐Université Evry Val d'Essonne‐Université Paris DiderotSaclay Plant SciencesBat 630, rue Noetzlin91405OrsayFrance
| | - Rainer Hedrich
- Molecular Plant Physiology and BiophysicsJulius‐von‐Sachs Institute for BiosciencesBiocenterUniversity of WürzburgJulius‐von‐Sachs‐Platz 2D‐97082WürzburgGermany
| | - M. Rob G. Roelfsema
- Molecular Plant Physiology and BiophysicsJulius‐von‐Sachs Institute for BiosciencesBiocenterUniversity of WürzburgJulius‐von‐Sachs‐Platz 2D‐97082WürzburgGermany
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Azoulay-Shemer T, Palomares A, Bagheri A, Israelsson-Nordstrom M, Engineer CB, Bargmann BO, Stephan AB, Schroeder JI. Guard cell photosynthesis is critical for stomatal turgor production, yet does not directly mediate CO2 - and ABA-induced stomatal closing. Plant J 2015; 83:567-81. [PMID: 26096271 PMCID: PMC4532624 DOI: 10.1111/tpj.12916] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 05/29/2015] [Accepted: 06/09/2015] [Indexed: 05/03/2023]
Abstract
Stomata mediate gas exchange between the inter-cellular spaces of leaves and the atmosphere. CO2 levels in leaves (Ci) are determined by respiration, photosynthesis, stomatal conductance and atmospheric [CO2 ]. [CO2 ] in leaves mediates stomatal movements. The role of guard cell photosynthesis in stomatal conductance responses is a matter of debate, and genetic approaches are needed. We have generated transgenic Arabidopsis plants that are chlorophyll-deficient in guard cells only, expressing a constitutively active chlorophyllase in a guard cell specific enhancer trap line. Our data show that more than 90% of guard cells were chlorophyll-deficient. Interestingly, approximately 45% of stomata had an unusual, previously not-described, morphology of thin-shaped chlorophyll-less stomata. Nevertheless, stomatal size, stomatal index, plant morphology, and whole-leaf photosynthetic parameters (PSII, qP, qN, FV '/FM' ) were comparable with wild-type plants. Time-resolved intact leaf gas-exchange analyses showed a reduction in stomatal conductance and CO2 -assimilation rates of the transgenic plants. Normalization of CO2 responses showed that stomata of transgenic plants respond to [CO2 ] shifts. Detailed stomatal aperture measurements of normal kidney-shaped stomata, which lack chlorophyll, showed stomatal closing responses to [CO2 ] elevation and abscisic acid (ABA), while thin-shaped stomata were continuously closed. Our present findings show that stomatal movement responses to [CO2 ] and ABA are functional in guard cells that lack chlorophyll. These data suggest that guard cell CO2 and ABA signal transduction are not directly modulated by guard cell photosynthesis/electron transport. Moreover, the finding that chlorophyll-less stomata cause a 'deflated' thin-shaped phenotype, suggests that photosynthesis in guard cells is critical for energization and guard cell turgor production.
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Affiliation(s)
- Tamar Azoulay-Shemer
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Axxell Palomares
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Andish Bagheri
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Maria Israelsson-Nordstrom
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
| | - Cawas B. Engineer
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Bastiaan O.R. Bargmann
- Biology Department, Center for Genomics and Systems Biology, New York University, New York, NY 10003, USA
| | - Aaron B. Stephan
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Julian I. Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
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Suetsugu N, Takami T, Ebisu Y, Watanabe H, Iiboshi C, Doi M, Shimazaki KI. Guard cell chloroplasts are essential for blue light-dependent stomatal opening in Arabidopsis. PLoS One 2014; 9:e108374. [PMID: 25250952 PMCID: PMC4177113 DOI: 10.1371/journal.pone.0108374] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 08/20/2014] [Indexed: 01/13/2023] Open
Abstract
Blue light (BL) induces stomatal opening through the activation of H+-ATPases with subsequent ion accumulation in guard cells. In most plant species, red light (RL) enhances BL-dependent stomatal opening. This RL effect is attributable to the chloroplasts of guard cell, the only cells in the epidermis possessing this organelle. To clarify the role of chloroplasts in stomatal regulation, we investigated the effects of RL on BL-dependent stomatal opening in isolated epidermis, guard cell protoplasts, and intact leaves of Arabidopsis thaliana. In isolated epidermal tissues and intact leaves, weak BL superimposed on RL enhanced stomatal opening while BL alone was less effective. In guard cell protoplasts, RL enhanced BL-dependent H+-pumping and DCMU, a photosynthetic electron transport inhibitor, eliminated this effect. RL enhanced phosphorylation levels of the H+-ATPase in response to BL, but this RL effect was not suppressed by DCMU. Furthermore, DCMU inhibited both RL-induced and BL-dependent stomatal opening in intact leaves. The photosynthetic rate in leaves correlated positively with BL-dependent stomatal opening in the presence of DCMU. We conclude that guard cell chloroplasts provide ATP and/or reducing equivalents that fuel BL-dependent stomatal opening, and that they indirectly monitor photosynthetic CO2 fixation in mesophyll chloroplasts by absorbing PAR in the epidermis.
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Affiliation(s)
- Noriyuki Suetsugu
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Tsuneaki Takami
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Yuuta Ebisu
- Graduate School of System Life Sciences, Kyushu University, Fukuoka, Japan
| | - Harutaka Watanabe
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Chihoko Iiboshi
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Michio Doi
- Faculty of Art and Science, Kyushu University, Fukuoka, Japan
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Wang SW, Li Y, Zhang XL, Yang HQ, Han XF, Liu ZH, Shang ZL, Asano T, Yoshioka Y, Zhang CG, Chen YL. Lacking chloroplasts in guard cells of crumpled leaf attenuates stomatal opening: both guard cell chloroplasts and mesophyll contribute to guard cell ATP levels. Plant Cell Environ 2014; 37:2201-2210. [PMID: 24506786 DOI: 10.1111/pce.12297] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 01/24/2014] [Indexed: 06/03/2023]
Abstract
Controversies regarding the function of guard cell chloroplasts and the contribution of mesophyll in stomatal movements have persisted for several decades. Here, by comparing the stomatal opening of guard cells with (crl-ch) or without chloroplasts (crl-no ch) in one epidermis of crl (crumpled leaf) mutant in Arabidopsis, we showed that stomatal apertures of crl-no ch were approximately 65-70% those of crl-ch and approximately 50-60% those of wild type. The weakened stomatal opening in crl-no ch could be partially restored by imposing lower extracellular pH. Correspondingly, the external pH changes and K(+) accumulations following fusicoccin (FC) treatment were greatly reduced in the guard cells of crl-no ch compared with crl-ch and wild type. Determination of the relative ATP levels in individual cells showed that crl-no ch guard cells contained considerably lower levels of ATP than did crl-ch and wild type after 2 h of white light illumination. In addition, guard cell ATP levels were lower in the epidermis than in leaves, which is consistent with the observed weaker stomatal opening response to white light in the epidermis than in leaves. These results provide evidence that both guard cell chloroplasts and mesophyll contribute to the ATP source for H(+) extrusion by guard cells.
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Affiliation(s)
- Shu-Wei Wang
- Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Science, Hebei Normal University, Shijiazhuang, 050024, China
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O'Carrigan A, Babla M, Wang F, Liu X, Mak M, Thomas R, Bellotti B, Chen ZH. Analysis of gas exchange, stomatal behaviour and micronutrients uncovers dynamic response and adaptation of tomato plants to monochromatic light treatments. Plant Physiol Biochem 2014; 82:105-15. [PMID: 24935228 DOI: 10.1016/j.plaphy.2014.05.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 05/22/2014] [Indexed: 05/02/2023]
Abstract
Light spectrum affects the yield and quality of greenhouse tomato, especially over a prolonged period of monochromatic light treatments. Physiological and chemical analysis was employed to investigate the influence of light spectral (blue, green and red) changes on growth, photosynthesis, stomatal behaviour, leaf pigment, and micronutrient levels. We found that plants are less affected under blue light treatment, which was evident by the maintenance of higher A, gs, Tr, and stomatal parameters and significantly lower VPD and Tleaf as compared to those plants grown in green and red light treatments. Green and red light treatments led to significantly larger increase in the accumulation of Fe, B, Zn, and Cu than blue light. Moreover, guard cell length, width, and volume all showed highly significant positive correlations to gs, Tr and negative links to VPD. There was negative impact of monochromatic lights-induced accumulation of Mn, Cu, and Zn on photosynthesis, leaf pigments and plant growth. Furthermore, most of the light-induced significant changes of the physiological traits were partially recovered at the end of experiment. A high degree of morphological and physiological plasticity to blue, green and red light treatments suggested that tomato plants may have developed mechanisms to adapt to the light treatments. Thus, understanding the optimization of light spectrum for photosynthesis and growth is one of the key components for greenhouse tomato production.
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Affiliation(s)
- Andrew O'Carrigan
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia
| | - Mohammad Babla
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia
| | - Feifei Wang
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia; School of Agricultural Science, University of Tasmania, Hobart, TAS, 7001, Australia
| | - Xiaohui Liu
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia; School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Michelle Mak
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia
| | - Richard Thomas
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia
| | - Bill Bellotti
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia
| | - Zhong-Hua Chen
- School of Science and Health, University of Western Sydney, Penrith, 2751, NSW, Australia.
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Lawson T, Simkin AJ, Kelly G, Granot D. Mesophyll photosynthesis and guard cell metabolism impacts on stomatal behaviour. New Phytol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Kollist H, Nuhkat M, Roelfsema MRG. Closing gaps: linking elements that control stomatal movement. New Phytol 2014; 203:44-62. [PMID: 24800691 DOI: 10.1111/nph.12832] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 03/27/2014] [Indexed: 05/18/2023]
Abstract
Stomata are an attractive experimental system in plant biology, because the responses of guard cells to environmental signals can be directly linked to changes in the aperture of stomatal pores. In this review, the mechanics of stomatal movement are discussed in relation to ion transport in guard cells. Emphasis is placed on the ion pumps, transporters, and channels in the plasma membrane, as well as in the vacuolar membrane. The biophysical properties of transport proteins for H(+), K(+), Ca(2+), and anions are discussed and related to their function in guard cells during stomatal movements. Guard cell signaling pathways for ABA, CO2, ozone, microbe-associated molecular patterns (MAMPs) and blue light are presented. Special attention is given to the regulation of the slow anion channel (SLAC) and SLAC homolog (SLAH)-type anion channels by the ABA signalosome. Over the last decade, several knowledge gaps in the regulation of ion transport in guard cells have been closed. The current state of knowledge is an excellent starting point for tackling important open questions concerning stress tolerance in plants.
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Affiliation(s)
- Hannes Kollist
- Institute of Technology, University of Tartu, Nooruse 1, Tartu, 50411, Estonia
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Abstract
Previous studies have suggested that the red light and CO2 responses of stomata are caused by a signal from the mesophyll to the guard cells. Experiments were conducted to test the idea that this signal is a vapour-phase ion. Stomata in isolated epidermes of Tradescantia pallida were found to respond to air ions created by an electrode that was positioned under the epidermes. Anthocyanins in the epidermes of this species were observed to change colour in response to these air ions, and this change in colour was attributed to changes in pH. A similar change in lower epidermal colour was observed in intact leaves upon illumination and with changes in CO2 concentration. Based on the change in epidermal colour, the pH of the epidermis was estimated to be approximately 7.0 in darkness and 6.5 in the light. Stomata in isolated epidermes responded to pH when suspended over (but not in contact with) solutions of different pH. We speculate that stomatal responses to CO2 and light are caused by vapour-phase ions, possibly hydronium ions that change the pH of the epidermis.
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Affiliation(s)
- Keith A Mott
- Biology Department, Utah State University, Logan, UT, 84322-5305, USA
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Busch FA. Opinion: the red-light response of stomatal movement is sensed by the redox state of the photosynthetic electron transport chain. Photosynth Res 2014; 119:131-40. [PMID: 23483292 DOI: 10.1007/s11120-013-9805-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 02/14/2013] [Indexed: 05/03/2023]
Abstract
Guard cells regulate CO2 uptake and water loss of a leaf by controlling stomatal movement in response to environmental factors such as CO2, humidity, and light. The mechanisms by which stomata respond to red light are actively debated in the literature, and even after decades of research it is still controversial whether stomatal movement is related to photosynthesis or not. This review summarizes the current knowledge of the red-light response of stomata. A comparison of published evidence suggests that stomatal movement is controlled by the redox state of photosynthetic electron transport chain components, in particular the redox state of plastoquinone. Potential consequences for the modeling of stomatal conductance are discussed.
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Affiliation(s)
- Florian A Busch
- Plant Science Division, Research School of Biology, College of Medicine Biology and the Environment, The Australian National University, Linnaeus Building (Bldg 134) Linnaeus Way, Canberra, ACT, 0200, Australia,
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Fujita T, Noguchi K, Terashima I. Apoplastic mesophyll signals induce rapid stomatal responses to CO2 in Commelina communis. New Phytol 2013; 199:395-406. [PMID: 23560389 DOI: 10.1111/nph.12261] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 03/06/2013] [Indexed: 05/18/2023]
Abstract
Previous studies have suggested that the mesophyll contributes to stomatal CO(2) responses. The effects of changes in CO(2) concentration (100 or 700 ppm) on stomatal responses in red or white light were examined microscopically in a leaf segment, an epidermal strip and an epidermal strip placed on a mesophyll segment of Commelina communis, all mounted on a buffer-containing gel. In both red and white light, stomata of the leaf segment opened/closed rapidly at low/high CO(2). In red light, epidermal strip stomata barely responded to CO(2). In white light, they opened at low CO(2), but hardly closed at high CO(2). Stomata of the epidermal strip placed on the mesophyll responded in the same manner as those on the leaf segment. Insertion of a doughnut-shaped cellophane spacer (but not polyethylene spacer) between the epidermal strip and the mesophyll hardly altered these responses. Stomata in leaf segments treated with 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), a photosynthesis inhibitor, did not open in red light, but opened/closed at low/high CO(2) in white light. These results indicate that the apoplast transfer of 'mesophyll signals' and the stomatal opening at low CO(2) are dependent on photosynthesis, whereas the stomatal closure at high CO(2) is independent of photosynthesis.
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Affiliation(s)
- Takashi Fujita
- Plant Sciences, Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1130033, Japan
| | - Ko Noguchi
- Plant Sciences, Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1130033, Japan
| | - Ichiro Terashima
- Plant Sciences, Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1130033, Japan
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41
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Roy M, Gonneau C, Rocheteau A, Berveiller D, Thomas JC, Damesin C, Selosse MA. Why do mixotrophic plants stay green? A comparison between green and achlorophyllous orchid individuals in situ. ECOL MONOGR 2013. [DOI: 10.1890/11-2120.1] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Abstract
Since the first recordings of single potassium channel activities in the plasma membrane of guard cells more than 25 years ago, patch-clamp studies discovered a variety of ion channels in all cell types and plant species under inspection. Their properties differed in a cell type- and cell membrane-dependent manner. Guard cells, for which the existence of plant potassium channels was initially documented, advanced to a versatile model system for studying plant ion channel structure, function, and physiology. Interestingly, one of the first identified potassium-channel genes encoding the Shaker-type channel KAT1 was shown to be highly expressed in guard cells. KAT1-type channels from Arabidopsis thaliana and its homologs from other species were found to encode the K+-selective inward rectifiers that had already been recorded in early patch-clamp studies with guard cells. Within the genome era, additional Arabidopsis Shaker-type channels appeared. All nine members of the Arabidopsis Shaker family are localized at the plasma membrane, where they either operate as inward rectifiers, outward rectifiers, weak voltage-dependent channels, or electrically silent, but modulatory subunits. The vacuole membrane, in contrast, harbors a set of two-pore K+ channels. Just very recently, two plant anion channel families of the SLAC/SLAH and ALMT/QUAC type were identified. SLAC1/SLAH3 and QUAC1 are expressed in guard cells and mediate Slow- and Rapid-type anion currents, respectively, that are involved in volume and turgor regulation. Anion channels in guard cells and other plant cells are key targets within often complex signaling networks. Here, the present knowledge is reviewed for the plant ion channel biology. Special emphasis is drawn to the molecular mechanisms of channel regulation, in the context of model systems and in the light of evolution.
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Affiliation(s)
- Rainer Hedrich
- University of Wuerzburg, Institute for Molecular Plant Physiology and Biophysics, Wuerzburg, Germany; and King Saud University, Riyadh, Saudi Arabia
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Lysenko V. Fluorescence kinetic parameters and cyclic electron transport in guard cell chloroplasts of chlorophyll-deficient leaf tissues from variegated weeping fig (Ficus benjamina L.). Planta 2012; 235:1023-1033. [PMID: 22134781 DOI: 10.1007/s00425-011-1560-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 11/21/2011] [Indexed: 05/27/2023]
Abstract
Residual chlorophyll in chlorophyll-deficient (albino) areas of variegated leaves of Ficus benjamina originates from guard cell chloroplasts. Photosynthetic features of green and albino sectors of F. benjamina were studied by imaging the distribution of the fluorescence decrease ratio Rfd within a leaf calculated from maximum (Fm) and steady-state leaf chlorophyll fluorescence (Fs) at 690 and 740 nm. Local areas of albino sectors demonstrated an abnormally high Rfd(740)/Rfd(690) ratio. Fluorescence transients excited in albino sectors at red (640 and 690 nm) wavelengths showed an abrupt decrease of the Rfd values (0.4 and 0.1, correspondingly) as compared with those excited at blue wavelengths (1.7-2.4). This "Red Drop" was not observed for green sectors. Normal and chlorophyll-deficient leaf sectors of F. benjamina were also tested for linear and cyclic electron transport in thylakoids. The tests have been performed studying fluorescence at a steady-state phase with CO(2)-excess impulse feeding, photoacoustic signal generated by pulse light source at wavelengths selectively exciting PSI, fluorescence kinetics under anaerobiosis and fluorescence changes observed by dual-wavelength excitation method. The data obtained for albino sectors strongly suggest the possibility of a cyclic electron transport simultaneously occurring in guard cell thylakoids around photosystems I and II under blue light, whereas linear electron transport is absent or insufficient.
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Affiliation(s)
- Vladimir Lysenko
- Scientific Research Institute of Biology, Southern Federal University, Stachky Ave 194/1, 344090, Rostov-on-Don, Russia.
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44
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Roelfsema MRG, Hedrich R, Geiger D. Anion channels: master switches of stress responses. Trends Plant Sci 2012; 17:221-9. [PMID: 22381565 DOI: 10.1016/j.tplants.2012.01.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 01/13/2012] [Accepted: 01/19/2012] [Indexed: 05/18/2023]
Abstract
During stress, plant cells activate anion channels and trigger the release of anions across the plasma membrane. Recently, two new gene families have been identified that encode major groups of anion channels. The SLAC/SLAH channels are characterized by slow voltage-dependent activation (S-type), whereas ALMT genes encode rapid-activating channels (R-type). Both S- and R-type channels are stimulated in guard cells by the stress hormone ABA, which leads to stomatal closure. Besides their role in ABA-dependent stomatal movement, anion channels are also activated by biotic stress factors such as microbe-associated molecular patterns (MAMPs). Given that anion channels occur throughout the plant kingdom, they are likely to serve a general function as master switches of stress responses.
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Affiliation(s)
- M Rob G Roelfsema
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082 Würzburg, Germany.
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45
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Abstract
Stomata, functionally specialized small pores on the surfaces of leaves, regulate the flow of gases in and out of plants. The pore is opened by an increase in osmotic pressure in the guard cells, resulting in the uptake of water. The subsequent increase in cell volume inflates the guard cell and culminates with the opening of the pore. Although guard cells can be regarded as one of the most thoroughly investigated cell types, our knowledge of the signaling pathways which regulate guard cell function remains fragmented. Recent research in guard cells has led to several new hypotheses, however, it is still a matter of debate as to whether guard cells function autonomously or are subject to regulation by their neighboring mesophyll cells.This review synthesizes what is known about the mechanisms and genes critical for modulating stomatal movement. Recent progress on the regulation of guard cell function is reviewed here including the involvement of environmental signals such as light, the concentration of atmospheric CO2 and endogenous plant hormones. In addition we re-evaluate the important role of organic acids such as malate and fumarate play in guard cell metabolism in this process.
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Affiliation(s)
- Wagner L Araújo
- Max-Planck Institute for Molecular Plant Physiology; Potsdam-Golm, Germany
| | - Alisdair R Fernie
- Max-Planck Institute for Molecular Plant Physiology; Potsdam-Golm, Germany
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal; Universidade Federal de Viçosa; Max-Planck Partner Group; MG, Viçosa, Brazil
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46
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Sibbernsen E, Mott KA. Stomatal responses to flooding of the intercellular air spaces suggest a vapor-phase signal between the mesophyll and the guard cells. Plant Physiol 2010; 153:1435-42. [PMID: 20472750 PMCID: PMC2899896 DOI: 10.1104/pp.110.157685] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Accepted: 05/11/2010] [Indexed: 05/19/2023]
Abstract
Flooding the intercellular air spaces of leaves with water was shown to cause rapid closure of stomata in Tradescantia pallida, Lactuca serriola, Helianthus annuus, and Oenothera caespitosa. The response occurred when water was injected into the intercellular spaces, vacuum infiltrated into the intercellular spaces, or forced into the intercellular spaces by pressurizing the xylem. Injecting 50 mm KCl or silicone oil into the intercellular spaces also caused stomata to close, but the response was slower than with distilled water. Epidermis-mesophyll grafts for T. pallida were created by placing the epidermis of one leaf onto the exposed mesophyll of another leaf. Stomata in these grafts opened under light but closed rapidly when water was allowed to wick between epidermis and the mesophyll. When epidermis-mesophyll grafts were constructed with a thin hydrophobic filter between the mesophyll and epidermis stomata responded normally to light and CO(2). These data, when taken together, suggest that the effect of water on stomata is caused partly by dilution of K(+) in the guard cell and partly by the existence of a vapor-phase signal that originates in the mesophyll and causes stomata to open in the light.
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47
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Hu H, Boisson-Dernier A, Israelsson-Nordström M, Böhmer M, Xue S, Ries A, Godoski J, Kuhn JM, Schroeder JI. Carbonic anhydrases are upstream regulators of CO2-controlled stomatal movements in guard cells. Nat Cell Biol 2010; 12:87-93; sup pp 1-18. [PMID: 20010812 PMCID: PMC2906259 DOI: 10.1038/ncb2009] [Citation(s) in RCA: 276] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 11/18/2009] [Indexed: 11/09/2022]
Abstract
The continuing rise in atmospheric CO2 causes stomatal pores in leaves to close and thus globally affects CO2 influx into plants, water use efficiency and leaf heat stress. However, the CO2-binding proteins that control this response remain unknown. Moreover, which cell type responds to CO2, mesophyll or guard cells, and whether photosynthesis mediates this response are matters of debate. We demonstrate that Arabidopsis thaliana double-mutant plants in the beta-carbonic anhydrases betaCA1 and betaCA4 show impaired CO2-regulation of stomatal movements and increased stomatal density, but retain functional abscisic-acid and blue-light responses. betaCA-mediated CO2-triggered stomatal movements are not, in first-order, linked to whole leaf photosynthesis and can function in guard cells. Furthermore, guard cell betaca-overexpressing plants exhibit instantaneous enhanced water use efficiency. Guard cell expression of mammalian alphaCAII complements the reduced sensitivity of ca1 ca4 plants, showing that carbonic anhydrase-mediated catalysis is an important mechanism for betaCA-mediated CO2-induced stomatal closure and patch clamp analyses indicate that CO2/HCO3- transfers the signal to anion channel regulation. These findings, together with ht1-2 (ref. 9) epistasis analysis demonstrate that carbonic anhydrases function early in the CO2 signalling pathway, which controls gas-exchange between plants and the atmosphere.
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Affiliation(s)
- Honghong Hu
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Aurélien Boisson-Dernier
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Maria Israelsson-Nordström
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Maik Böhmer
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Shaowu Xue
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Amber Ries
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Jan Godoski
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Josef M. Kuhn
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Julian I. Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA 92093-0116, USA
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48
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Kim TH, Böhmer M, Hu H, Nishimura N, Schroeder JI. Guard cell signal transduction network: advances in understanding abscisic acid, CO2, and Ca2+ signaling. Annu Rev Plant Biol 2010; 61:561-91. [PMID: 20192751 PMCID: PMC3056615 DOI: 10.1146/annurev-arplant-042809-112226] [Citation(s) in RCA: 808] [Impact Index Per Article: 57.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO(2) influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO(2) activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO(2) and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO(2)-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.
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Affiliation(s)
| | | | - Honghong Hu
- University of California, San Diego, Division of Biological Sciences, Section of Cell and Developmental Biology, La Jolla, California 92093-0116
| | - Noriyuki Nishimura
- University of California, San Diego, Division of Biological Sciences, Section of Cell and Developmental Biology, La Jolla, California 92093-0116
| | - Julian I. Schroeder
- University of California, San Diego, Division of Biological Sciences, Section of Cell and Developmental Biology, La Jolla, California 92093-0116
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Abstract
The mechanisms by which stomata respond to red light and CO(2) are unknown, but much of the current literature assumes that these mechanisms reside wholly within the guard cells. However, responses of guard cells in isolated epidermes are typically much smaller than those in leaves, and there are several lines of evidence in the literature suggesting that the mesophyll is necessary for these responses in leaves. This paper advances the opinion that although guard cells may have small direct responses to red light and CO(2), most of the stomatal response to these factors in leaves is caused by an unknown signal that originates in the mesophyll.
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Affiliation(s)
- Keith A Mott
- Biology Department, Utah State University, Logan, UT, 84322-5305, USA.
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