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Lin QJ, Chu J, Kumar V, Yuan DP, Li ZM, Mei Q, Xuan YH. Protein Phosphatase 2A Catalytic Subunit PP2A-1 Enhances Rice Resistance to Sheath Blight Disease. Front Genome Ed 2021; 3:632136. [PMID: 34713255 PMCID: PMC8525387 DOI: 10.3389/fgeed.2021.632136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 02/08/2021] [Indexed: 11/22/2022] Open
Abstract
Rice (Oryza sativa) production is damaged to a great extent by sheath blight disease (ShB). However, the defense mechanism in rice against this disease is largely unknown. Previous transcriptome analysis identified a significantly induced eukaryotic protein phosphatase 2A catalytic subunit 1 (PP2A-1) after the inoculation of Rhizoctonia solani. Five genes encoding PP2A exist in rice genome, and these five genes are ubiquitously expressed in different tissues and stages. Inoculation of R. solani showed that the genome edited pp2a-1 mutants using the CRISPR/Cas9 were more susceptible to ShB than the wild-type control, but other PP2A gene mutants exhibited similar response to ShB compared to wild-type plants. In parallel, PP2A-1 expression level was higher in the activation tagging line, and PP2A-1 overexpression inhibited plant height and promoted the resistance to ShB. PP2A-1-GFP was localized in the cytoplasm and nucleus. In addition, R. solani-dependent induction kinetics of pathogen-related genes PBZ1 and PR1b was lower in pp2a-1 mutants but higher in PP2A-1 activation line compared to those in the wild-type. In conclusion, our analysis shows that PP2A-1 is a member of protein phosphatase, which regulates rice resistance to ShB. This result broadens the understanding of the defense mechanism against ShB and provides a potential target for rice breeding for disease resistance.
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Affiliation(s)
- Qiu Jun Lin
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Jin Chu
- Institute of Plant Protection, Liaoning Academy of Agricultural Sciences, Shenyang, China
| | - Vikranth Kumar
- Division of Applied Life Science (BK21 Program), Plant Molecular Biology and Biotechnology Research Center (PMBBRC), Gyeongsang National University, Jinju, South Korea
| | - De Peng Yuan
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Zhi Min Li
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Qiong Mei
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Yuan Hu Xuan
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
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Tang RJ, Wang C, Li K, Luan S. The CBL-CIPK Calcium Signaling Network: Unified Paradigm from 20 Years of Discoveries. TRENDS IN PLANT SCIENCE 2020; 25:604-617. [PMID: 32407699 DOI: 10.1016/j.tplants.2020.01.009] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/16/2020] [Accepted: 01/27/2020] [Indexed: 05/18/2023]
Abstract
Calcium (Ca2+) serves as an essential nutrient as well as a signaling agent in all eukaryotes. In plants, calcineurin B-like proteins (CBLs) are a unique group of Ca2+ sensors that decode Ca2+ signals by activating a family of plant-specific protein kinases known as CBL-interacting protein kinases (CIPKs). Interactions between CBLs and CIPKs constitute a signaling network that enables information integration and physiological coordination in response to a variety of extracellular cues such as nutrient deprivation and abiotic stresses. Studies in the past two decades have established a unified paradigm that illustrates the functions of CBL-CIPK complexes in controlling membrane transport through targeting transporters and channels in the plasma membrane and tonoplast.
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Affiliation(s)
- Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Chao Wang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Kunlun Li
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.
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Takaoka Y, Miyagawa S, Nakamura A, Egoshi S, Tsukiji S, Ueda M. Hoechst-tagged Fluorescein Diacetate for the Fluorescence Imaging-based Assessment of Stomatal Dynamics in Arabidopsis thaliana. Sci Rep 2020; 10:5333. [PMID: 32210301 PMCID: PMC7093514 DOI: 10.1038/s41598-020-62239-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 03/11/2020] [Indexed: 11/18/2022] Open
Abstract
In plants, stomata regulate water loss through transpiration for plant growth and survival in response to various environmental stressors; and simple methods to assess stomatal dynamics are needed for physiological studies. Herein, we report a fluorescence-imaging-based method using fluorescein diacetate tagged with Hoechst 33342, a nuclear staining chemical probe (HoeAc2Fl) for the qualitative assessment of stomatal dynamics. In our method, the stomatal movement is inferred by simple monitoring of the fluorescence intensity in the nucleus of the stomata.
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Affiliation(s)
- Yousuke Takaoka
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan.,Precursory Research for Embryonic Science and Technology (PREST), Japan Science and Technology Agency, 5 Sanbancho, Chiyoda-ku, Tokyo, 102-0075, Japan
| | - Saki Miyagawa
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Akinobu Nakamura
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan
| | - Syusuke Egoshi
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Shinya Tsukiji
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan. .,Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan. .,Frontier Research Institute for Materials Science (FRIMS), Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan.
| | - Minoru Ueda
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan. .,Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan.
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Shi S, Li S, Asim M, Mao J, Xu D, Ullah Z, Liu G, Wang Q, Liu H. The Arabidopsis Calcium-Dependent Protein Kinases (CDPKs) and Their Roles in Plant Growth Regulation and Abiotic Stress Responses. Int J Mol Sci 2018; 19:E1900. [PMID: 29958430 PMCID: PMC6073581 DOI: 10.3390/ijms19071900] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 06/21/2018] [Indexed: 02/06/2023] Open
Abstract
As a ubiquitous secondary messenger in plant signaling systems, calcium ions (Ca2+) play essential roles in plant growth and development. Within the cellular signaling network, the accurate decoding of diverse Ca2+ signal is a fundamental molecular event. Calcium-dependent protein kinases (CDPKs), identified commonly in plants, are a kind of vital regulatory protein deciphering calcium signals triggered by various developmental and environmental stimuli. This review chiefly introduces Ca2+ distribution in plant cells, the classification of Arabidopsis thaliana CDPKs (AtCDPKs), the identification of the Ca2+-AtCDPK signal transduction mechanism and AtCDPKs’ functions involved in plant growth regulation and abiotic stress responses. The review presents a comprehensive overview of AtCDPKs and may contribute to the research of CDPKs in other plants.
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Affiliation(s)
- Sujuan Shi
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Shugui Li
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
- College of Agriculture, Qingdao Agricultural University, Qingdao 266109, China.
| | - Muhammad Asim
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Jingjing Mao
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Dizhi Xu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Zia Ullah
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Guanshan Liu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Qian Wang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Haobao Liu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
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Jezek M, Blatt MR. The Membrane Transport System of the Guard Cell and Its Integration for Stomatal Dynamics. PLANT PHYSIOLOGY 2017; 174:487-519. [PMID: 28408539 PMCID: PMC5462021 DOI: 10.1104/pp.16.01949] [Citation(s) in RCA: 177] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 04/11/2017] [Indexed: 05/17/2023]
Abstract
Stomatal guard cells are widely recognized as the premier plant cell model for membrane transport, signaling, and homeostasis. This recognition is rooted in half a century of research into ion transport across the plasma and vacuolar membranes of guard cells that drive stomatal movements and the signaling mechanisms that regulate them. Stomatal guard cells surround pores in the epidermis of plant leaves, controlling the aperture of the pore to balance CO2 entry into the leaf for photosynthesis with water loss via transpiration. The position of guard cells in the epidermis is ideally suited for cellular and subcellular research, and their sensitivity to endogenous signals and environmental stimuli makes them a primary target for physiological studies. Stomata underpin the challenges of water availability and crop production that are expected to unfold over the next 20 to 30 years. A quantitative understanding of how ion transport is integrated and controlled is key to meeting these challenges and to engineering guard cells for improved water use efficiency and agricultural yields.
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Affiliation(s)
- Mareike Jezek
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Michael R Blatt
- Laboratory of Plant Physiology and Biophysics, University of Glasgow, Glasgow G12 8QQ, United Kingdom
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Zhang SH. The Genetic Basis of Abiotic Stress Resistance in Extremophilic Fungi: The Genes Cloning and Application. FUNGAL APPLICATIONS IN SUSTAINABLE ENVIRONMENTAL BIOTECHNOLOGY 2016. [DOI: 10.1007/978-3-319-42852-9_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Ronzier E, Corratgé-Faillie C, Sanchez F, Prado K, Brière C, Leonhardt N, Thibaud JB, Xiong TC. CPK13, a noncanonical Ca2+-dependent protein kinase, specifically inhibits KAT2 and KAT1 shaker K+ channels and reduces stomatal opening. PLANT PHYSIOLOGY 2014; 166:314-26. [PMID: 25037208 PMCID: PMC4149717 DOI: 10.1104/pp.114.240226] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 07/15/2014] [Indexed: 05/18/2023]
Abstract
Ca(2) (+)-dependent protein kinases (CPKs) form a large family of 34 genes in Arabidopsis (Arabidopsis thaliana). Based on their dependence on Ca(2+), CPKs can be sorted into three types: strictly Ca(2+)-dependent CPKs, Ca(2+)-stimulated CPKs (with a significant basal activity in the absence of Ca(2+)), and essentially calcium-insensitive CPKs. Here, we report on the third type of CPK, CPK13, which is expressed in guard cells but whose role is still unknown. We confirm the expression of CPK13 in Arabidopsis guard cells, and we show that its overexpression inhibits light-induced stomatal opening. We combine several approaches to identify a guard cell-expressed target. We provide evidence that CPK13 (1) specifically phosphorylates peptide arrays featuring Arabidopsis K(+) Channel KAT2 and KAT1 polypeptides, (2) inhibits KAT2 and/or KAT1 when expressed in Xenopus laevis oocytes, and (3) closely interacts in plant cells with KAT2 channels (Förster resonance energy transfer-fluorescence lifetime imaging microscopy). We propose that CPK13 reduces stomatal aperture through its inhibition of the guard cell-expressed KAT2 and KAT1 channels.
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Affiliation(s)
- Elsa Ronzier
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Claire Corratgé-Faillie
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Frédéric Sanchez
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Karine Prado
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Christian Brière
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Nathalie Leonhardt
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Jean-Baptiste Thibaud
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
| | - Tou Cheu Xiong
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 386, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5004, SupAgro, and Université Montpellier 2, Laboratoire de Biochimie & Physiologie Moléculaire des Plantes, F-34060 Montpellier cedex 2, France (E.R., C.C.-F., F.S., K.P., J.-B.T., T.C.X.);Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France (C.B.);Université Paul Sabatier, Pôle de Biotechnologies Végétales 24, Chemin de Borde Rouge, Boite Postale 42617 Auzeville, 31326 Castanet-Tolosan, France (C.B.); andLaboratoire de Biologie du Développement des Plantes, Unité Mixte de Recherche 7265 Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université Aix-Marseille II, Commissariat à l'Energie Atomique Cadarache Bat 156, 13108 St. Paul Lez Durance, France (N.L.)
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The stomata frontline of plant interaction with the environment-perspectives from hormone regulation. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11515-012-1193-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Cousson A. Indolyl-3-butyric acid-induced Arabidopsis stomatal opening mediated by 3',5'-cyclic guanosine-monophosphate. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2010; 48:977-986. [PMID: 20951600 DOI: 10.1016/j.plaphy.2010.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 09/17/2010] [Accepted: 09/19/2010] [Indexed: 05/30/2023]
Abstract
It has been pharmacologically suggested that 3',5'-cyclic guanosine-monophosphate (cGMP) mediates indolyl-3-butyric acid (IBA)-induced stomatal opening. In Arabidopsis thaliana (L.) Heynh., such investigations compared the wild type (Columbia and Ws ecotypes) to mutants knockout for either GTP-binding protein (G protein) α subunit 1 (gpa1-4), putative G protein-coupled receptor 1 (gcr1-5), calcineurin B-like isoform 1 (cbl1) or 9 (cbl9), or the NADPH oxidases AtrbohD and AtrbohF (atrbohD/F). Stomatal opening to IBA or the permeant cGMP analogue, 8-bromo-cGMP (8-Br-cGMP) was abolished in the atrbohD/F mutant. The IBA response was fully or partially suppressed, respectively, in the gcr1-5 mutant, or the gpa1-4 and cbl1 mutants. In the cbl9 mutant, the response to IBA or 8-Br-cGMP, respectively, was partially or fully suppressed. Phenylarsine oxide (PAO) affected the IBA response, which the cbl1 mutant overlapped or the gpa1-4 and cbl9 mutants increased up to 100% inhibition. 6-anilino-5,8-quinolinedione, mas17, the (Rp)-diastereomer of 8-bromo-3',5'-cyclic guanosine monophosphorothioate (Rp-8-Br-cGMPS), nicotinamide, ruthenium red (RRed), 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA), cyclosporine A (CsA) and FK506 converged to affect the IBA response, which the gpa1-4 and cbl9 mutants overlapped or the cbl1 mutant and PAO increased up to 100% inhibition. Rp-8-Br-cGMPS, nicotinamide, RRed, BAPTA, CsA or FK506 paralled the cbl9 and atrbohD/F mutants to abolish the 8-Br-cGMP response. Based on so far revealed features of these mutants and pharmacological compounds, these results confirmed cGMP as a Ca(2+)-mobilizing second messenger for apoplastic auxin whose perception and transduction would implicate a seven-transmembrane receptor - G protein - guanylyl cyclase unit at the guard cell plasma membrane.
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Affiliation(s)
- A Cousson
- CEA, DSV, IBEB, Lab Echanges Membran & Signalisation, Saint-Paul-lez-Durance F-13108, France.
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10
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Proteomic analysis of wheat embryos with 2-DE and liquid-phase chromatography (ProteomeLab PF-2D) — A wider perspective of the proteome. J Proteomics 2010; 73:1707-21. [DOI: 10.1016/j.jprot.2010.05.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 05/07/2010] [Accepted: 05/07/2010] [Indexed: 01/03/2023]
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11
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Liu Y, Zhang Y, Min J, Liu LL, Ma NQ, Feng YM, Liu D, Wang PZ, Huang DD, Zhuang Y, Zhang HL. Calcineurin promotes proliferation, migration, and invasion of small cell lung cancer. Tumour Biol 2010; 31:199-207. [DOI: 10.1007/s13277-010-0031-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2009] [Accepted: 03/18/2010] [Indexed: 10/19/2022] Open
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12
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Threonine at position 306 of the KAT1 potassium channel is essential for channel activity and is a target site for ABA-activated SnRK2/OST1/SnRK2.6 protein kinase. Biochem J 2009; 424:439-48. [DOI: 10.1042/bj20091221] [Citation(s) in RCA: 279] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Arabidopsis thaliana K+ channel KAT1 has been suggested to have a key role in mediating the aperture of stomata pores on the surface of plant leaves. Although the activity of KAT1 is thought to be regulated by phosphorylation, the endogenous pathway and the primary target site for this modification remained unknown. In the present study, we have demonstrated that the C-terminal region of KAT1 acts as a phosphorylation target for the Arabidopsis calcium-independent ABA (abscisic acid)-activated protein kinase SnRK2.6 (Snf1-related protein kinase 2.6). This was confirmed by LC-MS/MS (liquid chromatography tandem MS) analysis, which showed that Thr306 and Thr308 of KAT1 were modified by phosphorylation. The role of these specific residues was examined by single point mutations and measurement of KAT1 channel activities in Xenopus oocyte and yeast systems. Modification of Thr308 had minimal effect on KAT1 activity. On the other hand, modification of Thr306 reduced the K+ transport uptake activity of KAT1 in both systems, indicating that Thr306 is responsible for the functional regulation of KAT1. These results suggest that negative regulation of KAT1 activity, required for stomatal closure, probably occurs by phosphorylation of KAT1 Thr306 by the stress-activated endogenous SnRK2.6 protein kinase.
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Ligaba A, Kochian L, Piñeros M. Phosphorylation at S384 regulates the activity of the TaALMT1 malate transporter that underlies aluminum resistance in wheat. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 60:411-23. [PMID: 19563436 DOI: 10.1111/j.1365-313x.2009.03964.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In this study we examined the role of protein phosphorylation/dephosphorylation in the transport properties of the wheat (Triticum aestivum) root malate efflux transporter underlying Al resistance, TaALMT1. Pre-incubation of Xenopus laevis oocytes expressing TaALMT1 with protein kinase inhibitors (K252a and staurosporine) strongly inhibited both basal and Al(3+)-enhanced TaALMT1-mediated inward currents (malate efflux). Pre-incubation with phosphatase inhibitors (okadaic acid and cyclosporine A) resulted in a modest inhibition of the TaALMT1-mediated currents. Exposure to the protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA), enhanced TaALMT1-mediated inward currents. Since these observations suggest that TaALMT1 transport activity is regulated by PKC-mediated phosphorylation, we proceeded to modify candidate amino acids in the TaALMT1 protein in an effort to identify structural motifs underlying the process regulating phosphorylation. The transport properties of eight single point mutations (S56A, S183A, S324A, S337A, S351-352A, S384A, T323A and Y184F) generated in amino acid residues predicted to be phosphorylation sites and examined electrophysiologically. The basic transport properties of mutants S56A, S183A, S324A, S337A, S351-352A, T323A and Y184F were not altered relative to the wild-type TaALMT1. Likewise the sensitivity of these mutants to staurosporine resembled that observed for the wild-type transporter. However, the mutation S384A was noticeable, as in oocytes expressing this mutant protein TaALMT1-mediated basal and Al-enhanced currents were significantly inhibited, and the currents were insensitive to staurosporine or PMA. These findings indicate that S384 is an essential residue regulating TaALMT1 activity via direct protein phosphorylation, which precedes Al(3+) enhancement of transport activity.
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Affiliation(s)
- Ayalew Ligaba
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Tower Road, Cornell University, Ithaca, NY 14853-2901, USA
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14
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Luan S, Lan W, Chul Lee S. Potassium nutrition, sodium toxicity, and calcium signaling: connections through the CBL-CIPK network. CURRENT OPINION IN PLANT BIOLOGY 2009; 12:339-46. [PMID: 19501014 DOI: 10.1016/j.pbi.2009.05.003] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 05/05/2009] [Accepted: 05/06/2009] [Indexed: 05/02/2023]
Abstract
Plant roots take up numerous minerals from the soil. Some minerals (e.g., K(+)) are essential nutrients and others (e.g., Na(+)) are toxic for plant growth and development. In addition to the absolute level, the balance among the minerals is critical for their physiological functions. For instance, [K(+)]/[Na(+)] ratio and homeostasis often determine plant growth rate. Either low-K or high-Na in the soil represents a stress condition that severely affects plant life and agricultural production. Earlier observations indicated that higher soil Ca2(+) improve plants growth under low-K or high-Na condition, implying functional interaction among the three cations. Recent studies have begun to delineate the signaling mechanisms underlying such interactions. Either low-K(+) or high-Na(+) can trigger cellular Ca2(+) changes that lead to activation of complex signaling networks. One such network consists of Ca2(+) sensor proteins (e.g., CBLs) interacting with their target kinases (CIPKs). The CBL-CIPK signaling modules interact with and regulate the activity of a number of transporting proteins involved in the uptake and translocation of K(+) and Na(+), maintaining the "balance" of these cations in plants under stress conditions.
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Affiliation(s)
- Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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15
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Jain D, Roy N, Chattopadhyay D. CaZF, a plant transcription factor functions through and parallel to HOG and calcineurin pathways in Saccharomyces cerevisiae to provide osmotolerance. PLoS One 2009; 4:e5154. [PMID: 19365545 PMCID: PMC2664467 DOI: 10.1371/journal.pone.0005154] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Accepted: 03/13/2009] [Indexed: 01/19/2023] Open
Abstract
Salt-sensitive yeast mutants were deployed to characterize a gene encoding a C2H2 zinc finger protein (CaZF) that is differentially expressed in a drought-tolerant variety of chickpea (Cicer arietinum) and provides salinity-tolerance in transgenic tobacco. In Saccharomyces cerevisiae most of the cellular responses to hyper-osmotic stress is regulated by two interconnected pathways involving high osmolarity glycerol mitogen-activated protein kinase (Hog1p) and Calcineurin (CAN), a Ca(2+)/calmodulin-regulated protein phosphatase 2B. In this study, we report that heterologous expression of CaZF provides osmotolerance in S. cerevisiae through Hog1p and Calcineurin dependent as well as independent pathways. CaZF partially suppresses salt-hypersensitive phenotypes of hog1, can and hog1can mutants and in conjunction, stimulates HOG and CAN pathway genes with subsequent accumulation of glycerol in absence of Hog1p and CAN. CaZF directly binds to stress response element (STRE) to activate STRE-containing promoter in yeast. Transactivation and salt tolerance assays of CaZF deletion mutants showed that other than the transactivation domain a C-terminal domain composed of acidic and basic amino acids is also required for its function. Altogether, results from this study suggests that CaZF is a potential plant salt-tolerance determinant and also provide evidence that in budding yeast expression of HOG and CAN pathway genes can be stimulated in absence of their regulatory enzymes to provide osmotolerance.
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Affiliation(s)
- Deepti Jain
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, India
| | - Nilanjan Roy
- National Institute for Pharmaceutical Education and Research, SAS Nagar, Punjab, India
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16
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Abstract
In addition to light, water and CO(2), plants require a number of mineral nutrients, in particular the macronutrients nitrogen, sulphur, phosphorus, magnesium, calcium and potassium. After uptake from the soil by the root system they are either immediately assimilated into organic compounds or distributed within the plant for usage in different tissues. A good understanding of how the transport of macronutrients into and between plant cells is adjusted to different environmental conditions is essential to achieve an increase of nutrient usage efficiency and nutritional value in crops. Here, we review the current state of knowledge regarding the regulation of macronutrient transport, taking both a physiological and a mechanistic approach. We first describe how nutrient transport is linked to environmental and internal cues such as nutrient, carbon and water availability via hormonal, metabolic and physical signals. We then present information on the molecular mechanisms for regulation of transport proteins, including voltage gating, auto-inhibition, interaction with other proteins, oligomerization and trafficking. Combining of evidence for different nutrients, signals and regulatory levels creates an opportunity for making new connections within a large body of data, and thus contributes to an integrative understanding of nutrient transport.
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Affiliation(s)
- Anna Amtmann
- Plant Sciences Group, Faculty of Biomedical and Life Science, University of Glasgow, Glasgow G128QQ, UK
| | - Michael R Blatt
- Plant Sciences Group, Faculty of Biomedical and Life Science, University of Glasgow, Glasgow G128QQ, UK
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17
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Pandey S, Zhang W, Assmann SM. Roles of ion channels and transporters in guard cell signal transduction. FEBS Lett 2007; 581:2325-36. [PMID: 17462636 DOI: 10.1016/j.febslet.2007.04.008] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 04/03/2007] [Accepted: 04/03/2007] [Indexed: 12/16/2022]
Abstract
Stomatal complexes consist of pairs of guard cells and the pore they enclose. Reversible changes in guard cell volume alter the aperture of the pore and provide the major regulatory mechanism for control of gas exchange between the plant and the environment. Stomatal movement is facilitated by the activity of ion channels and ion transporters found in the plasma membrane and vacuolar membrane of guard cells. Progress in recent years has elucidated the molecular identities of many guard cell transport proteins, and described their modulation by various cellular signal transduction components during stomatal opening and closure prompted by environmental and endogenous stimuli.
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Affiliation(s)
- Sona Pandey
- Biology Department, Penn State University, 208 Mueller Laboratory, University Park, PA 16802, United States
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18
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Xu C, Jing R, Mao X, Jia X, Chang X. A wheat (Triticum aestivum) protein phosphatase 2A catalytic subunit gene provides enhanced drought tolerance in tobacco. ANNALS OF BOTANY 2007; 99:439-50. [PMID: 17272305 PMCID: PMC2802960 DOI: 10.1093/aob/mcl285] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 11/21/2006] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS Multiple copies of genes encoding the catalytic subunit (c) of protein phosphatase 2A (PP2A) are commonly found in plants. For some of these genes, expression is up-regulated under water stress. The aim of this study was to investigate expression and characterization of TaPP2Ac-1 from Triticum aestivum, and to evaluate the effects of TaPP2Ac-1 on Nicotiana benthamiana in response to water stress. METHODS TaPP2Ac-1 cDNA was isolated from wheat by in silico identification and RT-PCR amplification. Transcript levels of TaPP2Ac-1 were examined in wheat responding to water deficit. Copy numbers of TaPP2Ac-1 in wheat genomes and subcellular localization in onion epidermal cells were studied. Enzyme properties of the recombinant TaPP2Ac-1 protein were determined. In addition, studies were carried out in tobacco plants with pCAPE2-TaPP2Ac-1 under water-deficit conditions. KEY RESULTS TaPP2Ac-1 cDNA was cloned from wheat. Transcript levels of TaPP2Ac-1 in wheat seedlings were up-regulated under drought condition. One copy for this TaPP2Ac-1 was present in each of the three wheat genomes. TaPP2Ac-1 fused with GFP was located in the nucleus and cytoplasm of onion epidermis cells. The recombinant TaPP2Ac-1 gene was over-expressed in Escherichia coli and encoded a functional serine/threonine phosphatase. Transgenic tobacco plants over-expressing TaPP2Ac-1 exhibited stronger drought tolerance than non-transgenic tobacco plants. CONCLUSIONS Tobacco plants with pCAPE2-TaPP2Ac-1 appeared to be resistant to water deficit, as shown by their higher capacity to maintain leaf relative water content, leaf cell-membrane stability index, water-retention ability and water use efficiency under water stress. The results suggest that the physiological role of TaPP2Ac-1 is related to drought stress response, possibly through its involvement in drought-responding signal transduction pathways.
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Affiliation(s)
| | - Ruilian Jing
- The National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Crop Germplasm & Biotechnology, Ministry of Agriculture, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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19
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Marten H, Konrad KR, Dietrich P, Roelfsema MRG, Hedrich R. Ca2+-dependent and -independent abscisic acid activation of plasma membrane anion channels in guard cells of Nicotiana tabacum. PLANT PHYSIOLOGY 2007; 143:28-37. [PMID: 17142476 PMCID: PMC1761993 DOI: 10.1104/pp.106.092643] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2006] [Accepted: 11/26/2006] [Indexed: 05/12/2023]
Abstract
Drought induces stomatal closure, a response that is associated with the activation of plasma membrane anion channels in guard cells, by the phytohormone abscisic acid (ABA). In several species, this response is associated with changes in the cytoplasmic free Ca(2+) concentration. In Vicia faba, however, guard cell anion channels activate in a Ca(2+)-independent manner. Because of potential differences between species, Nicotiana tabacum guard cells were studied in intact plants, with simultaneous recordings of the plasma membrane conductance and the cytoplasmic free Ca(2+) concentration. ABA triggered transient rises in cytoplasmic Ca(2+) in the majority of the guard cells (14 out of 19). In seven out of 14 guard cells, the change in cytoplasmic free Ca(2+) closely matched the activation of anion channels, while the Ca(2+) rise was delayed in seven other cells. In the remaining five cells, ABA stimulated anion channels without a change in the cytoplasmic Ca(2+) level. Even though ABA could activate anion channels in N. tabacum guard cells independent of a rise in the cytoplasmic Ca(2+) concentration, patch clamp experiments showed that anion channels in these cells are stimulated by elevated Ca(2+) in an ATP-dependent manner. Guard cells thus seem to have evolved both Ca(2+)-independent and -dependent ABA signaling pathways. Guard cells of N. tabacum apparently utilize both pathways, while ABA signaling in V. faba seems to be restricted to the Ca(2+)-independent pathway.
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Affiliation(s)
- Holger Marten
- University of Wurzburg, Biocenter, Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, D-97082 Wurzburg, Germany
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20
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Lee JR, Park SC, Kim JY, Lee SS, Park Y, Cheong GW, Hahm KS, Lee SY. Molecular and functional characterization of a cyclophilin with antifungal activity from Chinese cabbage. Biochem Biophys Res Commun 2006; 353:672-8. [PMID: 17194440 DOI: 10.1016/j.bbrc.2006.12.102] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Accepted: 12/11/2006] [Indexed: 11/29/2022]
Abstract
An antifungal protein that inhibits the growth of filamentous fungal pathogens was isolated from Chinese cabbage (Brassica campestris L. ssp. pekinensis) by affinity chromatography on Affi-gel blue gel and ion exchange chromatography on CM-Sepharose. The N-terminal amino acid sequence of the protein was highly homologous to that of plant cyclophilins and consequently the protein was denoted as C-CyP. To understand the antifungal activity of C-CyP, we isolated a cDNA encoding its gene from a Chinese cabbage leaf cDNA library. The Chinese cabbage genome bears more than one C-CyP gene copy and C-CyP mRNA is highly expressed in all tissues except the seeds. Recombinant C-CyP catalyzed the cis-trans inter-conversion of the Ala-Pro bond of the substrate, which indicates this protein has peptidyl-prolyl cis-trans isomerase activity. It also inhibited the growth of several fungal pathogens.
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Affiliation(s)
- Jung Ro Lee
- Environmental Biotechnology National Core Research Center, Gyeongsang National University, Jinju, 660-701, Republic of Korea
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21
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Michard E, Dreyer I, Lacombe B, Sentenac H, Thibaud JB. Inward rectification of the AKT2 channel abolished by voltage-dependent phosphorylation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2005; 44:783-97. [PMID: 16297070 DOI: 10.1111/j.1365-313x.2005.02566.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The Arabidopsis K(+) channel AKT2 possesses the remarkable property that its voltage threshold for activation can be either within the physiological range (gating mode 1), or shifted towards considerably more positive voltages (gating mode 2). Gating mode 1 AKT2 channels behave as delayed K(+)-selective inward rectifiers; while gating mode 2 AKT2 channels are K(+)-selective 'open leaks' in the physiological range of membrane potential. In the present study we have investigated modulation of AKT2 current by effectors of phosphatases/kinases in COS cells and Xenopus oocytes. These experiments show that (i) dephosphorylation can result in AKT2 channel silencing; and (ii) phosphorylation by protein kinase A (PKA) favors both recruitment of silenced AKT2 channels and transition from gating mode 1 to gating mode 2. Interestingly, phosphorylation of AKT2 by PKA in COS cells and Xenopus oocytes is favored by hyperpolarization. Two PKA phosphorylation sites (S210 and S329) were pinpointed in the region of the pore inner mouth. The role of these phosphorylation sites in the switch between the two gating modes was assessed by electrophysiological characterization of mutant channels. The molecular aspects of AKT2 regulation by phosphorylation, and the possible physiological meaning of such regulation in the plant context, are discussed.
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Affiliation(s)
- Erwan Michard
- Biochimie et Physiologie Moléculaire des Plantes, UMR5004 Agro.M-CNRS-INRA-UM2, Montpellier, France
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22
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Wolf T, Guinot DR, Hedrich R, Dietrich P, Marten I. Nucleotides and Mg2+ ions differentially regulate K+ channels and non-selective cation channels present in cells forming the stomatal complex. PLANT & CELL PHYSIOLOGY 2005; 46:1682-9. [PMID: 16081526 DOI: 10.1093/pcp/pci184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Voltage-dependent inward-rectifying (K(in)) and outward-rectifying (K(out)) K(+) channels are capable of mediating K(+) fluxes across the plasma membrane. Previous studies on guard cells or heterologously expressed K(+) channels provided evidence for the requirement of ATP to maintain K(+) channel activity. Here, the nucleotide and Mg(2+) dependencies of time-dependent K(in) and K(out) channels from maize subsidiary cells were examined, showing that MgATP as well as MgADP function as channel activators. In addition to K(out) channels, these studies revealed the presence of another outward-rectifying channel type (MgC) in the plasma membrane that however gates in a nucleotide-independent manner. MgC represents a new channel type distinguished from K(out) channels by fast activation kinetics, inhibition by elevated intracellular Mg(2+) concentration, permeability for K(+) as well as for Na(+) and insensitivity towards TEA(+). Similar observations made for guard cells from Zea mays and Vicia faba suggest a conserved regulation of channel-mediated K(+) and Na(+) transport in both cell types and species.
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Affiliation(s)
- Thomas Wolf
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Bioscience, University of Wuerzburg, Germany
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23
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Sokolovski S, Hills A, Gay R, Garcia-Mata C, Lamattina L, Blatt MR. Protein phosphorylation is a prerequisite for intracellular Ca2+ release and ion channel control by nitric oxide and abscisic acid in guard cells. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2005; 43:520-9. [PMID: 16098106 DOI: 10.1111/j.1365-313x.2005.02471.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Recent work has indicated that nitric oxide (NO) and its synthesis are important elements of signal cascades in plant-pathogen defence, and are a prerequisite for drought and abscisic acid (ABA) responses in Arabidopsis thaliana and Vicia faba guard cells. NO regulates inward-rectifying K+ channels and Cl- channels of Vicia guard cells via intracellular Ca2+ release. However, its integration with related signals, including the actions of serine-threonine protein kinases, is less well defined. We report here that the elevation of cytosolic-free [Ca2+] ([Ca2+]i) mediated by NO in guard cells is reversibly inhibited by the broad-range protein kinase antagonists staurosporine and K252A, but not by the tyrosine kinase antagonist genistein. The effects of kinase antagonism translate directly to a loss of NO-sensitivity of the inward-rectifying K+ channels and background (Cl- channel) current, and to a parallel loss in sensitivity of the K+ channels to ABA. These results demonstrate that NO-dependent signals can be modulated through protein phosphorylation upstream of intracellular Ca2+ release, and they implicate a target for protein kinase control in ABA signalling that feeds into NO-dependent Ca2+ release.
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Affiliation(s)
- Sergei Sokolovski
- Laboratory of Plant Physiology and Biophysics, Bower Building, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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24
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Ma X, Qian Q, Zhu D. Expression of a calcineurin gene improves salt stress tolerance in transgenic rice. PLANT MOLECULAR BIOLOGY 2005; 58:483-95. [PMID: 16021334 DOI: 10.1007/s11103-005-6162-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Accepted: 04/22/2005] [Indexed: 05/03/2023]
Abstract
Calcineurin is a Ca2+- and calmodulin-dependent serine/threonine phosphatase and has multiple functions in animal cells including regulating ionic homeostasis. We generated transgenic rice plants that not only expressed a truncated form of the catalytic subunit of mouse calcineurin, but also were able to grow and fertilize normally in the field. Notably, the expression of the mouse calcineurin gene in rice resulted in its higher salt stress tolerance than the non-transgenic rice. Physiological studies have indicated that the root growth of transgenic plants was less inhibited than the shoot growth, and that less Na+ was accumulated in the roots of transgenic plants after a prolonged period of salt stress. These findings imply that the heterologous calcineurin plays a significant role in maintaining ionic homeostasis and the integrity of plant roots when exposed to salt. In addition, the calcineurin gene expression in the stems of transgenic plants correlated with the increased expression of the Rab16A gene that encodes a group 2-type late-embryogenesis-abundant (LEA) protein. Altogether our findings provide the first genetic and physiological evidence that expression of the mouse calcineurin protein functionally improves the salt stress tolerance of rice partly by limiting Na+ accumulation in the roots.
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Affiliation(s)
- Xujun Ma
- Department of Biochemistry and Molecular Biology, National Laboratory of Medical Molecular Biology, School of Basic Medicine, Peking Union Medical College, Beijing, China
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25
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Buchanan BB, Luan S. Redox regulation in the chloroplast thylakoid lumen: a new frontier in photosynthesis research. JOURNAL OF EXPERIMENTAL BOTANY 2005; 56:1439-47. [PMID: 15851415 DOI: 10.1093/jxb/eri158] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Initially linked to photosynthesis, regulation by change in the redox state of thiol groups (S-S<-- -->2SH) is now known to occur throughout biology. Thus, in addition to serving important structural and catalytic functions, it is recognized that, in many cases, disulphide bonds can be broken and reformed for regulation. Several systems, each linking a hydrogen donor to an intermediary disulphide protein, act to effect changes that alter the activity of target proteins by change in the thiol redox state. Pertinent to the present discussion is the chloroplast ferredoxin/thioredoxin system, comprised of photoreduced ferredoxin, a thioredoxin, and the enzyme ferredoxin-thioredoxin reductase, that occur in the stroma. In this system, thioredoxin links the activity of enzymes to light: those enzymes functional in biosynthesis are reductively activated by light via thioredoxin (S-S-->2SH), whereas counterparts acting in degradation are deactivated under illumination conditions and are oxidatively activated in the dark (2SH-->S-S). Recent research has uncovered a new paradigm in which an immunophilin, FKBP13, and potentially other enzymes of the chloroplast thylakoid lumen are oxidatively activated in the light (2SH-->S-S). The present review provides a perspective on this recent work.
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Affiliation(s)
- Bob B Buchanan
- Department of Plant and Microbial Biology, 111 Koshland Hall, University of California, Berkeley, CA 94720, USA.
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26
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Sharma P, Sharma N, Deswal R. The molecular biology of the low-temperature response in plants. Bioessays 2005; 27:1048-59. [PMID: 16163711 DOI: 10.1002/bies.20307] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Plants growing in temperate regions are able to survive freezing temperatures from -5 degrees to -30 degrees C, depending on the species, through a process known as cold acclimation. In the last decade much work has been done on the molecular mechanisms of low temperature (LT) signal transduction and cold acclimation. Mutant studies and microarray analyses have revealed C-Repeat binding factor (CBF) -dependent and -independent signaling pathways in plants. Experimental evidence suggests the existence of 'potential LT sensors' but as yet there is no direct proof. A number of signal transducers such as various kinases/phosphatases have been demonstrated but the signal transduction pathways have not been elucidated. An understanding of the molecular basis of the signaling process, however, is of potential practical application. Designing new strategies to improve cold tolerance in crop varieties could increase the plant productivity and also expand the area under cultivation.
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Affiliation(s)
- Pragya Sharma
- Plant Molecular Physiology and Biochemistry Laboratory, Department of Botany, University of Delhi, Delhi, India
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27
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Marín-Manzano MC, Rodríguez-Rosales MP, Belver A, Donaire JP, Venema K. Heterologously expressed protein phosphatase calcineurin downregulates plant plasma membrane H+-ATPase activity at the post-translational level. FEBS Lett 2004; 576:266-70. [PMID: 15474049 DOI: 10.1016/j.febslet.2004.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Revised: 09/04/2004] [Accepted: 09/04/2004] [Indexed: 11/23/2022]
Abstract
To investigate the effects of calcineurin expression on cellular ion homeostasis in plants, we have obtained a transgenic cell culture of tomato, expressing constitutively activated yeast calcineurin. Transgenic cells exhibited reduced growth rates and proton extrusion activity in vivo. We show that reduction of plasma membrane H+-ATPase activity by expression of calcineurin is the basis for the observed phenotypes. Transgenic calli and cell suspensions displayed also increased salt tolerance and contained slightly higher Ca2+ and K+ levels. This demonstrates that calcineurin can modulate ion homeostasis in plants as it does in yeast by affecting the activity of primary ion transporters.
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Affiliation(s)
- Mari Carmen Marín-Manzano
- Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, Apartado 419, 18008 Granada, Spain
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28
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Sharma P, Deswal R. Detection and characterization of calcineurin-like activity in Brassica juncea and its activation by low temperature. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2004; 42:579-584. [PMID: 15331085 DOI: 10.1016/j.plaphy.2004.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Accepted: 06/04/2004] [Indexed: 05/24/2023]
Abstract
Here we describe a method for detecting calcineurin-like activity in Brassica juncea seedlings. The activity was standardized with respect to all the assay components. The optimum reaction time for the assay was found to be 10 min at 0.75 microM of R II phosphopeptide, a specific substrate for calcineurin. Stimulation of activity by CaM (0.1 microM) and CaCl2 (1 mM) was observed. The enzyme showed maximum activity in 125 mM Tris, 200 mM NaCl and 20 mM MgCl2 solution. The activity was differentially distributed in root, shoot and hypocotyls. It was maximum in roots (2.8 nM PO4 released/mg protein), followed by hypocotyls (0.95 nM PO4 released/mg protein) and cotyledonary leaves (0.85 nM PO4 released/mg protein), respectively. Low temperature (LT) stress treatment (4 degrees C) of short durations (5 and 15 min) showed a substantial increase in the activity. Maximum increase was observed in cotyledonary leaves (34.8%), followed by roots (25.6%) and hypocotyls (5.25%), respectively after LT treatment of 5 min suggesting its probable involvement in early signaling events. Besides, in vitro phosphorylation studies also showed activation of phosphatase by LT. Hence, the study indicates probable involvement of calcineurin-like activity in early cold stress signaling. Moreover, this optimized activity assay could be adopted to detect calcineurin-like activity in other plants.
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Affiliation(s)
- Pragya Sharma
- Plant Molecular Physiology and Biochemistry Laboratory, Department of Botany, University of Delhi, Delhi 110007, India
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29
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He Z, Li L, Luan S. Immunophilins and parvulins. Superfamily of peptidyl prolyl isomerases in Arabidopsis. PLANT PHYSIOLOGY 2004; 134:1248-67. [PMID: 15047905 PMCID: PMC419802 DOI: 10.1104/pp.103.031005] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2003] [Revised: 12/16/2003] [Accepted: 12/19/2003] [Indexed: 05/17/2023]
Abstract
Immunophilins are defined as receptors for immunosuppressive drugs including cyclosporin A, FK506, and rapamycin. The cyclosporin A receptors are referred to as cyclophilins (CYPs) and FK506- and rapamycin-binding proteins are abbreviated as FKBPs. These two groups of proteins (collectively called immunophilins) share little sequence homology, but both have peptidyl prolyl cis/trans isomerase (PPIase) activity that is involved in protein folding processes. Studies have identified immunophilins in all organisms examined including bacteria, fungi, animals, and plants. Nevertheless, the physiological function of immunophilins is poorly understood in any organism. In this study, we have surveyed the genes encoding immunophilins in Arabidopsis genome. A total of 52 genes have been found to encode putative immunophilins, among which 23 are putative FKBPs and 29 are putative CYPs. This is by far the largest immunophilin family identified in any organism. Both FKBPs and CYPs can be classified into single domain and multiple domain members. The single domain members contain a basic catalytic domain and some of them have signal sequences for targeting to a specific organelle. The multiple domain members contain not only the catalytic domain but also defined modules that are involved in protein-protein interaction or other functions. A striking feature of immunophilins in Arabidopsis is that a large fraction of FKBPs and CYPs are localized in the chloroplast, a possible explanation for why plants have a larger immunophilin family than animals. Parvulins represent another family of PPIases that are unrelated to immunophilins in protein sequences and drug binding properties. Three parvulin genes were found in Arabidopsis genome. The expression of many immunophilin and parvulin genes is ubiquitous except for those encoding chloroplast members that are often detected only in the green tissues. The large number of genes and diversity of structure domains and cellular localization make PPIases a versatile superfamily of proteins that clearly function in many cellular processes in plants.
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Affiliation(s)
- Zengyong He
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
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30
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Saez A, Apostolova N, Gonzalez-Guzman M, Gonzalez-Garcia MP, Nicolas C, Lorenzo O, Rodriguez PL. Gain-of-function and loss-of-function phenotypes of the protein phosphatase 2C HAB1 reveal its role as a negative regulator of abscisic acid signalling. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 37:354-69. [PMID: 14731256 DOI: 10.1046/j.1365-313x.2003.01966.x] [Citation(s) in RCA: 247] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
HAB1 was originally cloned on the basis of sequence homology to ABI1 and ABI2, and indeed, a multiple sequence alignment of 32 Arabidopsis protein phosphatases type-2C (PP2Cs) reveals a cluster composed by the four closely related proteins, ABI1, ABI2, HAB1 and At1g17550 (here named HAB2). Characterisation of transgenic plants harbouring a transcriptional fusion ProHAB1: green fluorescent protein (GFP) indicates that HAB1 is broadly expressed within the plant, including key target sites of abscisic acid (ABA) action as guard cells or seeds. The expression of the HAB1 mRNA in vegetative tissues is strongly upregulated in response to exogenous ABA. In this work, we show that constitutive expression of HAB1 in Arabidopsis under a cauliflower mosaic virus (CaMV) 35S promoter led to reduced ABA sensitivity both in seeds and vegetative tissues, compared to wild-type plants. Thus, in the field of ABA signalling, this work represents an example of a stable phenotype in planta after sustained overexpression of a PP2C genes. Additionally, a recessive T-DNA insertion mutant of HAB1 was analysed in this work, whereas previous studies of recessive alleles of PP2C genes were carried out with intragenic revertants of the abi1-1 and abi2-1 mutants that carry missense mutations in conserved regions of the PP2C domain. In the presence of exogenous ABA, hab1-1 mutant shows ABA-hypersensitive inhibition of seed germination; however, its transpiration rate was similar to that of wild-type plants. The ABA-hypersensitive phenotype of hab1-1 seeds together with the reduced ABA sensitivity of 35S:HAB1 plants are consistent with a role of HAB1 as a negative regulator of ABA signalling. Finally, these results provide new genetic evidence on the function of a PP2C in ABA signalling.
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Affiliation(s)
- Angela Saez
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Camino de Vera, E-46022 Valencia, Spain
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31
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Chérel I. Regulation of K+ channel activities in plants: from physiological to molecular aspects. JOURNAL OF EXPERIMENTAL BOTANY 2004; 55:337-51. [PMID: 14739260 DOI: 10.1093/jxb/erh028] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Plant voltage-gated channels belonging to the Shaker family participate in sustained K+ transport processes at the cell and whole plant levels, such as K+ uptake from the soil solution, long-distance K+ transport in the xylem and phloem, and K+ fluxes in guard cells during stomatal movements. The attention here is focused on the regulation of these transport systems by protein-protein interactions. Clues to the identity of the regulatory mechanisms have been provided by electrophysiological approaches in planta or in heterologous systems, and through analogies with their animal counterparts. It has been shown that, like their animal homologues, plant voltage-gated channels can assemble as homo- or heterotetramers associating polypeptides encoded by different Shaker genes, and that they can bind auxiliary subunits homologous to those identified in mammals. Furthermore, several regulatory processes (involving, for example, protein kinases and phosphatases, G proteins, 14-3-3s, or syntaxins) might be common to plant and animal Shakers. However, the molecular identification of plant channel partners is still at its beginning. This paper reviews current knowledge on plant K+ channel regulation at the physiological and molecular levels, in the light of the corresponding knowledge in animal cells, and discusses perspectives for the deciphering of regulatory networks in the future.
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Affiliation(s)
- Isabelle Chérel
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004, Agro-M/INRA/CNRS/UM2, Montpellier, France.
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Yoo JH, Cheong MS, Park CY, Moon BC, Kim MC, Kang YH, Park HC, Choi MS, Lee JH, Jung WY, Yoon HW, Chung WS, Lim CO, Lee SY, Cho MJ. Regulation of the Dual Specificity Protein Phosphatase, DsPTP1, through Interactions with Calmodulin. J Biol Chem 2004; 279:848-58. [PMID: 14570888 DOI: 10.1074/jbc.m310709200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Reversible phosphorylation is a key mechanism for the control of intercellular events in eukaryotic cells. In animal cells, Ca2+/CaM-dependent protein phosphorylation and dephosphorylation are implicated in the regulation of a number of cellular processes. However, little is known on the functions of Ca2+/CaM-dependent protein kinases and phosphatases in Ca2+ signaling in plants. From an Arabidopsis expression library, we isolated cDNA encoding a dual specificity protein phosphatase 1, which is capable of hydrolyzing both phosphoserine/threonine and phosphotyrosine residues of the substrates. Using a gel overlay assay, we identified two Ca2+-dependent CaM binding domains (CaMBDI in the N terminus and CaMBDII in the C terminus). Specific binding of CaM to two CaMBD was confirmed by site-directed mutagenesis, a gel mobility shift assay, and a competition assay using a Ca2+/CaM-dependent enzyme. At increasing concentrations of CaM, the biochemical activity of dual specificity protein phosphatase 1 on the p-nitrophenyl phosphate (pNPP) substrate was increased, whereas activity on the phosphotyrosine of myelin basic protein (MBP) was inhibited. Our results collectively indicate that calmodulin differentially regulates the activity of protein phosphatase, dependent on the substrate. Based on these findings, we propose that the Ca2+ signaling pathway is mediated by CaM cross-talks with a protein phosphorylation signal pathway in plants via protein dephosphorylation.
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Affiliation(s)
- Jae Hyuk Yoo
- Division of Applied Life Science, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701, Korea
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NG CARLK, MCAINSH MARTINR. Encoding specificity in plant calcium signalling: hot-spotting the ups and downs and waves. ANNALS OF BOTANY 2003; 92:477-85. [PMID: 12933365 PMCID: PMC4243675 DOI: 10.1093/aob/mcg173] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Calcium ions function as intracellular second messengers in regulating a plethora of cellular processes from acclimative stress responses to survival and programmed cell death. The generation of specificity in Ca2+ signals is dependent on influx and efflux from the extracellular milieu, cytosol and intracellular organelles. One aspect of plant Ca2+ signalling that is currently attracting a great deal of interest is how 'Ca2+-signatures', specific spatio-temporal changes in cytosolic-free Ca2+, encode the necessary information to bring about this range of physiological responses. Here, current information is reviewed on how Ca2+-signatures are generated in plant cells and how stimulus-specific information can be encoded in the form of Ca2+-signatures.
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Affiliation(s)
- CARL K.‐Y. NG
- Department of Botany, University College Dublin, Belfield, Dublin 4, Republic of Ireland
| | - MARTIN R. MCAINSH
- Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Bailrigg, Lancaster LA1 4YQ, UK
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Abstract
Phosphorylation and dephosphorylation of a protein often serve as an "on-and-off" switch in the regulation of cellular activities. Recent studies demonstrate the involvement of protein phosphorylation in almost all signaling pathways in plants. A significant portion of the sequenced Arabidopsis genome encodes protein kinases and protein phosphatases that catalyze reversible phosphorylation. For optimal regulation, kinases and phosphatases must strike a balance in any given cell. Only a very small fraction of the thousands of protein kinases and phosphatases in plants has been studied experimentally. Nevertheless, the available results have demonstrated critical functions for these enzymes in plant growth and development. While serine/threonine phosphorylation is widely accepted as a predominant modification of plant proteins, the function of tyrosine phosphorylation, desptie its overwhelming importance in animal systems, had been largely neglected until recently when tyrosine phosphatases (PTPs) were characterized from plants. This review focuses on the structure, regulation, and function of protein phosphatases in higher plants.
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Affiliation(s)
- Sheng Luan
- Department of Plant and Microbial Biology, University of California at Berkeley, Berkeley, California 94720, USA.
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García-Mata C, Lamattina L. Abscisic acid, nitric oxide and stomatal closure - is nitrate reductase one of the missing links? TRENDS IN PLANT SCIENCE 2003; 8:20-6. [PMID: 12523996 DOI: 10.1016/s1360-1385(02)00009-2] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Once plant endogenous nitric oxide (NO) production had been proved, NO research was directed toward both the source and the targets of this extremely bioactive molecule. As in mammals, plant NO was first thought to be generated mainly by a NO synthase-like enzymatic activity. However, nitrate reductase (NR)-dependent NO production is now receiving much of the attention because of the ubiquity of this enzyme in higher plant tissues and the precise regulation of its NO-production activity. NO has been reported to be a signal in many and diverse physiological processes, such as growth and biotic and abiotic stresses. Recently, NO has been shown to affect stomatal closure and interact with abscisic acid signaling pathways. We propose NR as a putative component in the signaling cascade of ABA-induced stomatal closure.
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Affiliation(s)
- Carlos García-Mata
- Instituto de Investigaciones Biológicas, Universidad Nacional de Mar del Plata, CC 1245, Argentina
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The effect of water potential on accumulation of some essential elements in sugarbeet leaves, Beta vulgaris ssp. vulgaris. ZBORNIK MATICE SRPSKE ZA PRIRODNE NAUKE 2003. [DOI: 10.2298/zmspn0304039m] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
An investigation has been conducted on the effect of reduced water potential in nutrient solution on the accumulation of some essential macro- and micro nutrients in the aboveground pails of young sugarbeet plants. Plants of 8 different sugarbeet genotypes were exposed for 21 days to a nutrient solution whose water potential of 0.1 MPa was regulated by PEG. Contents of N, P, K Ca, Mg, Fe, Mn, Cu and Zn declined in all genotypes under water deficiency but the intensity of reduction varied among the genotypes. The results indicated that some harmful effects of water deficiency could be attributed to disturbances in plant mineral nutrition, especially the lack of N, P, and Mg, as well as to impaired ratios between the contents of particular elements, especially K/Ca.
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Gupta R, Mould RM, He Z, Luan S. A chloroplast FKBP interacts with and affects the accumulation of Rieske subunit of cytochrome bf complex. Proc Natl Acad Sci U S A 2002; 99:15806-11. [PMID: 12424338 PMCID: PMC137797 DOI: 10.1073/pnas.222550399] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Immunophilins are intracellular receptors of the immunosuppressants cyclosporin A, FK506, and rapamycin. Although all immunophilins possess peptidyl-prolyl isomerase activity and are identified from a wide range of organisms, little is known about their cellular functions. We report the characterization and functional analysis of an FK506 and rapamycin-binding protein (AtFKBP13) from Arabidopsis. The AtFKBP13 protein is synthesized as a precursor that is imported into chloroplasts and processed to the mature form located in the thylakoid lumen, as shown by chloroplast import assays and Western blot analysis. Experiments show that AtFKBP13 is translocated across the thylakoid membrane by the DeltapH-dependent pathway. Yeast two-hybrid screening identified Rieske FeS protein, a subunit of the cytochrome bf complex in the photosynthetic electron transport chain, as an interacting partner for AtFKBP13. Both yeast two-hybrid and in vitro protein-protein interaction assays showed that the precursor, but not the mature form, of AtFKBP13 interacted with Rieske protein, suggesting that interaction between the two proteins occurs along the import pathway. When AtFKBP13 expression was suppressed by RNA interference method, the level of Rieske protein was significantly increased in the transgenic plants.
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Affiliation(s)
- Rajeev Gupta
- Department of Plant and Microbial Biology, University of California, Berkeley 94720, USA
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Köhler B, Blatt MR. Protein phosphorylation activates the guard cell Ca2+ channel and is a prerequisite for gating by abscisic acid. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2002; 32:185-194. [PMID: 12383084 DOI: 10.1046/j.1365-313x.2002.01414.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Protein phosphorylation and cytosolic-free [Ca2+] ([Ca2+]i) contribute to signalling cascades evoked by the water-stress hormone abscisic acid (ABA) that lead to stomatal closure in higher-plant leaves. ABA activates an inward-rectifying Ca2+ channel at the plasma membrane of stomatal guard cells, promoting Ca2+ entry by shifting the voltage-sensitivity of the channels. Because many of these effects could be mediated by kinase/phosphatase action at the membrane, we examined a role for protein (de-)phosphorylation in plasma membrane patches from Vicia guard cells. Ca2+ channel activity decayed rapidly in excised patches, and recovered on adding ATP (K1/2, 1.3 +/- 0.7 mm) but not the non-hydrolyzable analog ATPgammaS. ABA activation of the channel required the presence of ATP and like ABA, the 1/2 A-type protein phosphatase antagonists okadaic acid (OA) and calyculin A (CA) enhanced Ca2+ channel activity by increasing the open probability and number of active channels. Neither ATP nor the antagonists affected the mean open lifetime of the channel, suggesting an action through changes in closed lifetime distributions. Like ABA, OA and CA shifted the voltage-sensitivities of the Ca2+ current and [Ca2+]i increases in intact guard cells towards positive voltages. OA and CA also augmented the [Ca2+]i rise evoked by hyperpolarization and delayed its recovery. These results demonstrate a membrane-delimited interaction between 1/2 A-type protein phosphatase(s) and the Ca2+ channel or associated proteins, and they are consistent with a role for protein (de-)phosphorylation in ABA signalling mediated directly through Ca2+ channel gating that leads to [Ca2+]i increases in the guard cells.
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Affiliation(s)
- Barbara Köhler
- Laboratory of Plant Physiology and Biophysics, Institute of Biomedical and Life Sciences, University of Glasgow, UK
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39
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Reddy VS, Ali GS, Reddy ASN. Genes encoding calmodulin-binding proteins in the Arabidopsis genome. J Biol Chem 2002; 277:9840-52. [PMID: 11782485 DOI: 10.1074/jbc.m111626200] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Analysis of the recently completed Arabidopsis genome sequence indicates that approximately 31% of the predicted genes could not be assigned to functional categories, as they do not show any sequence similarity with proteins of known function from other organisms. Calmodulin (CaM), a ubiquitous and multifunctional Ca(2+) sensor, interacts with a wide variety of cellular proteins and modulates their activity/function in regulating diverse cellular processes. However, the primary amino acid sequence of the CaM-binding domain in different CaM-binding proteins (CBPs) is not conserved. One way to identify most of the CBPs in the Arabidopsis genome is by protein-protein interaction-based screening of expression libraries with CaM. Here, using a mixture of radiolabeled CaM isoforms from Arabidopsis, we screened several expression libraries prepared from flower meristem, seedlings, or tissues treated with hormones, an elicitor, or a pathogen. Sequence analysis of 77 positive clones that interact with CaM in a Ca(2+)-dependent manner revealed 20 CBPs, including 14 previously unknown CBPs. In addition, by searching the Arabidopsis genome sequence with the newly identified and known plant or animal CBPs, we identified a total of 27 CBPs. Among these, 16 CBPs are represented by families with 2-20 members in each family. Gene expression analysis revealed that CBPs and CBP paralogs are expressed differentially. Our data suggest that Arabidopsis has a large number of CBPs including several plant-specific ones. Although CaM is highly conserved between plants and animals, only a few CBPs are common to both plants and animals. Analysis of Arabidopsis CBPs revealed the presence of a variety of interesting domains. Our analyses identified several hypothetical proteins in the Arabidopsis genome as CaM targets, suggesting their involvement in Ca(2+)-mediated signaling networks.
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Affiliation(s)
- Vaka S Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA.
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40
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Abstract
A number of environmental conditions including drought, low humidity, cold and salinity subject plants to osmotic stress. A rapid plant response to such stress conditions is stomatal closure to reduce water loss from plants. From an external stress signal to stomatal closure, many molecular components constitute a signal transduction network that couples the stimulus to the response. Numerous studies have been directed to resolving the framework and molecular details of stress signalling pathways in plants. In guard cells, studies focus on the regulation of ion channels by abscisic acid (ABA), a chemical messenger for osmotic stress. Calcium, protein kinases and phosphatases, and membrane trafficking components have been shown to play a role in ABA signalling process in guard cells. Studies also implicate ABA-independent regulation of ion channels by osmotic stress. In particular, a direct osmosensing pathway for ion channel regulation in guard cells has been identified. These pathways form a complex signalling web that monitors water status in the environment and initiates responses in stomatal movements.
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Affiliation(s)
- S. Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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41
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Kutuzov MA, Bennett N, Andreeva AV. Interaction of plant protein Ser/Thr phosphatase PP7 with calmodulin. Biochem Biophys Res Commun 2001; 289:634-40. [PMID: 11716523 DOI: 10.1006/bbrc.2001.6020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have recently identified PP7, a novel group of plant protein Ser/Thr phosphatases, and hypothesized that PP7 may possess a calmodulin-binding site. To test this hypothesis, we assessed the effect of calmodulin on the activity of recombinant Arabidopsis thaliana PP7 and directly tested interaction between PP7 and calmodulin using surface plasmon resonance. Calmodulin exerted a moderate inhibitory effect on the phosphatase activity of PP7 with submicromolar affinity. PP7 specifically interacted with immobilized calmodulin (but not with recoverin, another EF hand Ca(2+)-binding protein) in a strictly Ca(2+)-dependent manner with nanomolar affinity. Deletion of an insert in the catalytic domain of PP7, predicted to function as a calmodulin-binding site, greatly decreased PP7 binding to calmodulin. These findings provide the first evidence for a plant protein phosphatase directly interacting with calmodulin and indicate that PP7 might be regulated by Ca(2+) levels in vivo.
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Affiliation(s)
- M A Kutuzov
- Laboratoire de Biophysique Moléculaire et Cellulaire, URA CNRS N520, Département de Biologie Moléculaire et Structurale, CEA-Grenoble, 17, rue des Martyrs, 38054 Grenoble Cedex 9, France.
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42
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Kwak JM, Murata Y, Baizabal-Aguirre VM, Merrill J, Wang M, Kemper A, Hawke SD, Tallman G, Schroeder JI. Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis. PLANT PHYSIOLOGY 2001; 127:473-485. [PMID: 11598222 DOI: 10.1104/pp.010428.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Inward-rectifying potassium (K+(in)) channels in guard cells have been suggested to provide a pathway for K+ uptake into guard cells during stomatal opening. To test the proposed role of guard cell K+(in) channels in light-induced stomatal opening, transgenic Arabidopsis plants were generated that expressed dominant negative point mutations in the K+(in) channel subunit KAT1. Patch-clamp analyses with transgenic guard cells from independent lines showed that K+(in) current magnitudes were reduced by approximately 75% compared with vector-transformed controls at -180 mV, which resulted in reduction in light-induced stomatal opening by 38% to 45% compared with vector-transformed controls. Analyses of intracellular K+ content using both sodium hexanitrocobaltate (III) and elemental x-ray microanalyses showed that light-induced K+ uptake was also significantly reduced in guard cells of K+(in) channel depressor lines. These findings support the model that K+(in) channels contribute to K+ uptake during light-induced stomatal opening. Furthermore, transpirational water loss from leaves was reduced in the K+(in) channel depressor lines. Comparisons of guard cell K+(in) current magnitudes among four different transgenic lines with different K+(in) current magnitudes show the range of activities of K+(in) channels required for guard cell K+ uptake during light-induced stomatal opening.
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Affiliation(s)
- J M Kwak
- Division of Biology, Cell and Developmental Biology Section, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
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43
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Kwak JM, Murata Y, Baizabal-Aguirre VM, Merrill J, Wang M, Kemper A, Hawke SD, Tallman G, Schroeder JI. Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis. PLANT PHYSIOLOGY 2001. [PMID: 11598222 DOI: 10.1104/pp.010428] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Inward-rectifying potassium (K+(in)) channels in guard cells have been suggested to provide a pathway for K+ uptake into guard cells during stomatal opening. To test the proposed role of guard cell K+(in) channels in light-induced stomatal opening, transgenic Arabidopsis plants were generated that expressed dominant negative point mutations in the K+(in) channel subunit KAT1. Patch-clamp analyses with transgenic guard cells from independent lines showed that K+(in) current magnitudes were reduced by approximately 75% compared with vector-transformed controls at -180 mV, which resulted in reduction in light-induced stomatal opening by 38% to 45% compared with vector-transformed controls. Analyses of intracellular K+ content using both sodium hexanitrocobaltate (III) and elemental x-ray microanalyses showed that light-induced K+ uptake was also significantly reduced in guard cells of K+(in) channel depressor lines. These findings support the model that K+(in) channels contribute to K+ uptake during light-induced stomatal opening. Furthermore, transpirational water loss from leaves was reduced in the K+(in) channel depressor lines. Comparisons of guard cell K+(in) current magnitudes among four different transgenic lines with different K+(in) current magnitudes show the range of activities of K+(in) channels required for guard cell K+ uptake during light-induced stomatal opening.
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Affiliation(s)
- J M Kwak
- Division of Biology, Cell and Developmental Biology Section, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
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44
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Dietrich P, Sanders D, Hedrich R. The role of ion channels in light-dependent stomatal opening. JOURNAL OF EXPERIMENTAL BOTANY 2001; 52:1959-67. [PMID: 11559731 DOI: 10.1093/jexbot/52.363.1959] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Stomatal opening represents a major determinant of plant productivity and stress management. Because plants lose water essentially through open stomata, volume control of the pore-forming guard cells represents a key step in the regulation of plant water status. These sensory cells are able to integrate various signals such as light, auxin, abscisic acid, and CO(2). Following signal perception, changes in membrane potential and activity of ion transporters finally lead to the accumulation of potassium salts and turgor pressure formation. This review analyses recent progress in molecular aspects of ion channel regulation and suggests how these developments impact on our understanding of light- and auxin-dependent stomatal action.
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Affiliation(s)
- P Dietrich
- Julius-von-Sachs-Institut für Biowissenschaften, Lehrstuhl für Molekulare Pflanzenphysiologie und Biophysik, Julius-von-Sachs-Platz 2, D-97082 Würzburg, Germany
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45
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Kwak JM, Murata Y, Baizabal-Aguirre VM, Merrill J, Wang M, Kemper A, Hawke SD, Tallman G, Schroeder JI. Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis. PLANT PHYSIOLOGY 2001; 127:473-485. [PMID: 11598222 DOI: 10.1104/pp.127.2.473] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Inward-rectifying potassium (K+(in)) channels in guard cells have been suggested to provide a pathway for K+ uptake into guard cells during stomatal opening. To test the proposed role of guard cell K+(in) channels in light-induced stomatal opening, transgenic Arabidopsis plants were generated that expressed dominant negative point mutations in the K+(in) channel subunit KAT1. Patch-clamp analyses with transgenic guard cells from independent lines showed that K+(in) current magnitudes were reduced by approximately 75% compared with vector-transformed controls at -180 mV, which resulted in reduction in light-induced stomatal opening by 38% to 45% compared with vector-transformed controls. Analyses of intracellular K+ content using both sodium hexanitrocobaltate (III) and elemental x-ray microanalyses showed that light-induced K+ uptake was also significantly reduced in guard cells of K+(in) channel depressor lines. These findings support the model that K+(in) channels contribute to K+ uptake during light-induced stomatal opening. Furthermore, transpirational water loss from leaves was reduced in the K+(in) channel depressor lines. Comparisons of guard cell K+(in) current magnitudes among four different transgenic lines with different K+(in) current magnitudes show the range of activities of K+(in) channels required for guard cell K+ uptake during light-induced stomatal opening.
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Affiliation(s)
- J M Kwak
- Division of Biology, Cell and Developmental Biology Section, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
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Isolation and Characterisation of cDNAs Encoding Protein Disulphide Isomerases and Cyclophilins in Wheat. J Cereal Sci 2001. [DOI: 10.1006/jcrs.2001.0382] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Ng CKY, Mcainsh MR, Gray JE, Hunt L, Leckie CP, Mills L, Hetherington AM. Calcium-based signalling systems in guard cells. THE NEW PHYTOLOGIST 2001; 151:109-120. [PMID: 33873375 DOI: 10.1046/j.1469-8137.2001.00152.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Calcium is a ubiquitous intracellular signal responsible for controlling numerous cellular processes in both plants and animals. As an example, Ca2+ has been shown to be a second messenger in the signal transduction pathways by which stomatal guard cells respond to external stimuli. Regulated increases in the cytosolic concentration of free calcium ions ([Ca2+ ]cyt ) in guard cells have been observed to be a common intermediate in many of the pathways leading to either opening or closing of the stomatal pore. This observation has prompted investigations into how specificity is encoded in the Ca2+ signal. It has been suggested that the key to generating stimulus-specific calcium signatures lies in the ability to access differentially the cellular machinery controlling calcium influx and release from intracellular stores. Several important components of the calcium-based signalling pathways have been identified in guard cells including cADPR, phospholipase C-InsP3 , InsP6 and H2 O2 . These data suggest that the pathways for intracellular mobilization of Ca2+ are evolutionarily conserved between plants and animals. ABBREVIATIONS: ABA, abscisic acid; [Ca2+ ]cyt , cytosolic free calcium concentration; [Ca2+ ]ext , external calcium concentration; IK,in ; inward-rectifying K+ currents; InsP3 , inositol-1,4,5-trisphosphate; InsP6 , inositol hexakisphosphate; PLC, phospholipase C; PLD, phospholipase D; PA, phosphatidic acid; H2 O2 , hydrogen peroxide; AAPK, ABA-activated serine-threonine protein kinase; cADPR, cyclic adenosine 5'-diphosphoribose; U73122, 1-(6-{[17â-3-methoxyestra-1,3,5(10)-trien-17-yl]amino}hexyl)-1H-pyrrole-2, 5-dione; RyR; ryanodine receptor; CICR; calcium-induced calcium-release; ICa , inward calcium current.
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Affiliation(s)
- CarL K-Y Ng
- Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YQ, UK
| | - Martin R Mcainsh
- Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YQ, UK
| | - Julie E Gray
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2UH, UK
| | - LeE Hunt
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2UH, UK
| | - Calum P Leckie
- Department of Physiological Sciences, The Medical School, University of Newcastle upon Tyne, NE2 4HH, UK
| | - Lewis Mills
- Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YQ, UK
| | - Alistair M Hetherington
- Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YQ, UK
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Cousson A. Pharmacological evidence for the implication of both cyclic GMP-dependent and -independent transduction pathways within auxin-induced stomatal opening in Commelina communis (L.). PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2001; 161:249-258. [PMID: 11448755 DOI: 10.1016/s0168-9452(01)00348-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It has been previously suggested that auxin-induced stomatal opening results from at least two transduction pathways, one of which involves cyclic GMP (cGMP) as the mediator within a Ca(2+) signalling cascade. This hypothesis was investigated further in epidermal peels of Commelina communis by comparing the effects of potential inhibitors of plant Ca(2+)-dependent enzymes on the stomatal opening responses to the auxin indolyl-3-butyric acid (IBA) and to the cGMP membrane-permeable derivative 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP). In the 30-50 &mgr;M range, the potential plant calmodulin (CaM) antagonist N-(aminohexyl)-5-chloro-1-naphthalenesulphonamide (W-7) positively interacted with IBA but not with 8-Br-cGMP to open the stomata. The CaM antagonists W-7 (in the 10-20 &mgr;M range) and N-(aminohexyl)-1-naphthalenesulphonamide (40 &mgr;M), the potential inhibitors of plant protein kinases 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (20 and 200 &mgr;M) and K-252a (0.6 &mgr;M), and cyclosporine A and FK506, potential inhibitors of plant homologs of Ca(2+)-CaM complex (Ca(2+)/CaM)-dependent protein phosphatase 2B, prevented the IBA and 8-Br-cGMP responses by about 70% and 100%, respectively. Together, these results provide indirect pharmacological evidence that, in addition to the cGMP-dependent pathway, the auxin signal is transduced through at least one cGMP-independent pathway.
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Affiliation(s)
- A Cousson
- CEA/Cadarache-DSV-DEVM, Laboratoire des Échanges Membranaires et Signalisation, UMR 163 CNRS-CEA, F-13108 Saint-Paul-lez-Durance, Cedex, France
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Schroeder JI, Allen GJ, Hugouvieux V, Kwak JM, Waner D. GUARD CELL SIGNAL TRANSDUCTION. ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY 2001; 52:627-658. [PMID: 11337411 DOI: 10.1146/annurev.arplant.52.1.627] [Citation(s) in RCA: 657] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Guard cells surround stomatal pores in the epidermis of plant leaves and stems. Stomatal pore opening is essential for CO2 influx into leaves for photosynthetic carbon fixation. In exchange, plants lose over 95% of their water via transpiration to the atmosphere. Signal transduction mechanisms in guard cells integrate hormonal stimuli, light signals, water status, CO2, temperature, and other environmental conditions to modulate stomatal apertures for regulation of gas exchange and plant survival under diverse conditions. Stomatal guard cells have become a highly developed model system for characterizing early signal transduction mechanisms in plants and for elucidating how individual signaling mechanisms can interact within a network in a single cell. In this review we focus on recent advances in understanding signal transduction mechanisms in guard cells.
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Affiliation(s)
- Julian I Schroeder
- Division of Biology, Cell and Developmental Biology Section and Center for Molecular Genetics, University of California, San Diego, La Jolla, California 92093-0116; e-mail:
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Petrussa E, Casolo V, Braidot E, Chiandussi E, Macrì F, Vianello A. Cyclosporin A induces the opening of a potassium-selective channel in higher plant mitochondria. J Bioenerg Biomembr 2001; 33:107-17. [PMID: 11456216 DOI: 10.1023/a:1010796314162] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The immunosuppressive drug, cyclosporin A (CsA), induces the generation of a transmembrane electrical potential difference (deltapsi) in deenergized plant mitochondria incubated in sucrose-based media. Build up of deltapsi is prevented by external monovalent cations in the order K+ > Rb+ = Li+ > Na+, or by the protonophore carbonyl cyanide p-trifluoromethoxyphenylhydrazone, which also collapses the deltapsi generated by CsA. Entry of K+ into mitochondria can be monitored as swelling by incubating the organelles in a medium containing KCl to maintain constant osmolarity. This swelling is inhibited by ATP and stimulated by CsA or valinomycin. In addition, in mitochondria energized by succinate, KCl causes a dissipation of deltapsi, with sigmoidal kinetics, which is favored by CsA. Therefore, plant mitochondria appear to possess a K+ selective, voltage-dependent channel, which is opened by CsA, regulated by the redox state, and inhibited by nucleotides. The hypothetical roles of this new K+ATP channel are discussed in relation to its potential involvement in mitochondrial volume regulation, thermogenesis, apoptosis, and/or prevention of reactive oxygen species formation in plants.
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Affiliation(s)
- E Petrussa
- Department of Biology and Agro-industrial Economics, University of Udine, Italy
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