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Wang X, Song X, Miao H, Feng S, Wu G. Natural variation in CYCLIC NUCLEOTIDE-GATED ION CHANNEL 4 reveals a novel role of calcium signaling in vegetative phase change in Arabidopsis. THE NEW PHYTOLOGIST 2024; 242:1043-1054. [PMID: 38184789 DOI: 10.1111/nph.19498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/07/2023] [Indexed: 01/08/2024]
Abstract
The timing of vegetative phase change (VPC) in plants is regulated by a temporal decline in the expression of miR156. Both exogenous cues and endogenous factors, such as temperature, light, sugar, nutrients, and epigenetic regulators, have been shown to affect VPC by altering miR156 expression. However, the genetic basis of natural variation in VPC remains largely unexplored. Here, we conducted a genome-wide association study on the variation of the timing of VPC in Arabidopsis. We identified CYCLIC NUCLEOTIDE-GATED ION CHANNEL 4 (CNGC4) as a significant locus associated with the diversity of VPC. Mutations in CNGC4 delayed VPC, accompanied by an increased expression level of miR156 and a corresponding decrease in SQUAMOSA PROMOTER BINDING-LIKE (SPL) gene expression. Furthermore, mutations in CNGC2 and CATION EXCHANGER 1/3 (CAX1/3) also led to a delay in VPC. Polymorphisms in the CNGC4 promoter contribute to the natural variation in CNGC4 expression and the diversity of VPC. Specifically, the early CNGC4 variant promotes VPC and enhances plant adaptation to local environments. In summary, our findings offer genetic insights into the natural variation in VPC in Arabidopsis, and reveal a previously unidentified role of calcium signaling in the regulation of VPC.
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Affiliation(s)
- Xiang Wang
- The State Key Laboratory of Subtropical Silviculture, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
| | - Xia Song
- The State Key Laboratory of Subtropical Silviculture, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
| | - Huaiqi Miao
- The State Key Laboratory of Subtropical Silviculture, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
| | - Shengjun Feng
- The State Key Laboratory of Subtropical Silviculture, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
| | - Gang Wu
- The State Key Laboratory of Subtropical Silviculture, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
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2
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Wang C, Luan S. Calcium homeostasis and signaling in plant immunity. CURRENT OPINION IN PLANT BIOLOGY 2024; 77:102485. [PMID: 38043138 DOI: 10.1016/j.pbi.2023.102485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 10/27/2023] [Accepted: 10/30/2023] [Indexed: 12/05/2023]
Abstract
Calcium (Ca2+) signaling consists of three steps: (1) initiation of a change in cellular Ca2+ concentration in response to a stimulus, (2) recognition of the change through direct binding of Ca2+ by its sensors, (3) transduction of the signal to elicit downstream responses. Recent studies have uncovered a central role for Ca2+ signaling in both layers of immune responses initiated by plasma membrane (PM) and intracellular receptors, respectively. These advances in our understanding are attributed to several lines of research, including invention of genetically-encoded Ca2+ reporters for the recording of intracellular Ca2+ signals, identification of Ca2+ channels and their gating mechanisms, and functional analysis of Ca2+ binding proteins (Ca2+ sensors). This review analyzes the recent literature that illustrates the importance of Ca2+ homeostasis and signaling in plant innate immunity, featuring intricate Ca2+dependent positive and negative regulations.
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Affiliation(s)
- Chao Wang
- 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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3
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Stéger A, Palmgren M. Hypothesis paper: the development of a regulatory layer in P2B autoinhibited Ca 2+-ATPases may have facilitated plant terrestrialization and animal multicellularization. PLANT SIGNALING & BEHAVIOR 2023; 18:2204284. [PMID: 37096591 PMCID: PMC10132250 DOI: 10.1080/15592324.2023.2204284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
With the appearance of plants and animals, new challenges emerged. These multicellular eukaryotes had to solve for example the difficulties of multifaceted communication between cells and adaptation to new habitats. In this paper, we are looking for one piece of the puzzle that made the development of complex multicellular eukaryotes possible with a focus on regulation of P2B autoinhibited Ca2+-ATPases. P2B ATPases pump Ca2+ out of the cytosol at the expense of ATP hydrolysis, and thereby maintain a steep gradient between the extra- and intracytosolic compartments which is utilized for Ca2+-mediated rapid cell signaling. The activity of these enzymes is regulated by a calmodulin (CaM)-responsive autoinhibitory region, which can be located in either termini of the protein, at the C-terminus in animals and at the N-terminus in plants. When the cytoplasmic Ca2+ level reaches a threshold, the CaM/Ca2+ complex binds to a calmodulin-binding domain (CaMBD) in the autoinhibitor, which leads to the upregulation of pump activity. In animals, protein activity is also controlled by acidic phospholipids that bind to a cytosolic portion of the pump. Here, we analyze the appearance of CaMBDs and the phospholipid-activating sequence and show that their evolution in animals and plants was independent. Furthermore, we hypothesize that different causes may have initiated the appearance of these regulatory layers: in animals, it is linked to the appearance of multicellularity, while in plants it co-occurs with their water-to-land transition.
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Affiliation(s)
- Anett Stéger
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Michael Palmgren
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
- CONTACT Michael Palmgren Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, FrederiksbergDK-1871, Denmark
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4
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Palmgren M. P-type ATPases: Many more enigmas left to solve. J Biol Chem 2023; 299:105352. [PMID: 37838176 PMCID: PMC10654040 DOI: 10.1016/j.jbc.2023.105352] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/02/2023] [Accepted: 10/05/2023] [Indexed: 10/16/2023] Open
Abstract
P-type ATPases constitute a large ancient super-family of primary active pumps that have diverse substrate specificities ranging from H+ to phospholipids. The significance of these enzymes in biology cannot be overstated. They are structurally related, and their catalytic cycles alternate between high- and low-affinity conformations that are induced by phosphorylation and dephosphorylation of a conserved aspartate residue. In the year 1988, all P-type sequences available by then were analyzed and five major families, P1 to P5, were identified. Since then, a large body of knowledge has accumulated concerning the structure, function, and physiological roles of members of these families, but only one additional family, P6 ATPases, has been identified. However, much is still left to be learned. For each family a few remaining enigmas are presented, with the intention that they will stimulate interest in continued research in the field. The review is by no way comprehensive and merely presents personal views with a focus on evolution.
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Affiliation(s)
- Michael Palmgren
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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5
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Costa A, Resentini F, Buratti S, Bonza MC. Plant Ca 2+-ATPases: From biochemistry to signalling. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119508. [PMID: 37290725 DOI: 10.1016/j.bbamcr.2023.119508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 05/30/2023] [Accepted: 05/30/2023] [Indexed: 06/10/2023]
Abstract
Calcium (Ca2+)-ATPases are ATP-dependent enzymes that transport Ca2+ ions against their electrochemical gradient playing the fundamental biological function of keeping the free cytosolic Ca2+ concentration in the submicromolar range to prevent cytotoxic effects. In plants, type IIB autoinhibited Ca2+-ATPases (ACAs) are localised both at the plasma membrane and at the endomembranes including endoplasmic reticulum (ER) and tonoplast and their activity is primarily regulated by Ca2+-dependent mechanisms. Instead, type IIA ER-type Ca2+-ATPases (ECAs) are present mainly at the ER and Golgi Apparatus membranes and are active at resting Ca2+. Whereas research in plants has historically focused on the biochemical characterization of these pumps, more recently the attention has been also addressed on the physiological roles played by the different isoforms. This review aims to highlight the main biochemical properties of both type IIB and type IIA Ca2+ pumps and their involvement in the shaping of cellular Ca2+ dynamics induced by different stimuli.
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Affiliation(s)
- Alex Costa
- Department of Biosciences, University of Milan, via Celoria 26, 20133 Milano, Italy; Institute of Biophysics, National Research Council of Italy (CNR), 20133 Milano, Italy.
| | - Francesca Resentini
- Department of Biosciences, University of Milan, via Celoria 26, 20133 Milano, Italy
| | - Stefano Buratti
- Department of Biosciences, University of Milan, via Celoria 26, 20133 Milano, Italy.
| | - Maria Cristina Bonza
- Department of Biosciences, University of Milan, via Celoria 26, 20133 Milano, Italy.
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6
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Wang J, Fu X, Zhang S, Chen G, Li S, Shangguan T, Zheng Y, Xu F, Chen ZH, Xu S. Evolutionary and Regulatory Pattern Analysis of Soybean Ca 2+ ATPases for Abiotic Stress Tolerance. FRONTIERS IN PLANT SCIENCE 2022; 13:898256. [PMID: 35665149 PMCID: PMC9161174 DOI: 10.3389/fpls.2022.898256] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
P2-type Ca2+ ATPases are responsible for cellular Ca2+ transport, which plays an important role in plant development and tolerance to biotic and abiotic stresses. However, the role of P2-type Ca2+ ATPases in stress response and stomatal regulation is still elusive in soybean. In this study, a total of 12 P2-type Ca2+ ATPases genes (GmACAs and GmECAs) were identified from the genome of Glycine max. We analyzed the evolutionary relationship, conserved motif, functional domain, gene structure and location, and promoter elements of the family. Chlorophyll fluorescence imaging analysis showed that vegetable soybean leaves are damaged to different extents under salt, drought, cold, and shade stresses. Real-time quantitative PCR (RT-qPCR) analysis demonstrated that most of the GmACAs and GmECAs are up-regulated after drought, cold, and NaCl treatment, but are down-regulated after shading stress. Microscopic observation showed that different stresses caused significant stomatal closure. Spatial location and temporal expression analysis suggested that GmACA8, GmACA9, GmACA10, GmACA12, GmACA13, and GmACA11 might promote stomatal closure under drought, cold, and salt stress. GmECA1 might regulate stomatal closure in shading stress. GmACA1 and GmECA3 might have a negative function on cold stress. The results laid an important foundation for further study on the function of P2-type Ca2+ ATPase genes GmACAs and GmECAs for breeding abiotic stress-tolerant vegetable soybean.
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Affiliation(s)
- Jian Wang
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xujun Fu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Sheng Zhang
- Taizhou Seed Administration Station, Taizhou, China
| | - Guang Chen
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Sujuan Li
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Tengwei Shangguan
- College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Yuanting Zheng
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Fei Xu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Zhong-Hua Chen
- School of Science, Western Sydney University, Penrith, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Shengchun Xu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
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7
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Structure, Function and Regulation of the Plasma Membrane Calcium Pump in Health and Disease. Int J Mol Sci 2022; 23:ijms23031027. [PMID: 35162948 PMCID: PMC8835232 DOI: 10.3390/ijms23031027] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/30/2021] [Accepted: 01/06/2022] [Indexed: 12/28/2022] Open
Abstract
In this review, I summarize the present knowledge of the structural and functional properties of the mammalian plasma membrane calcium pump (PMCA). It is outlined how the cellular expression of the different spliced isoforms of the four genes are regulated under normal and pathological conditions.
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8
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Fuglsang AT, Palmgren M. Proton and calcium pumping P-type ATPases and their regulation of plant responses to the environment. PLANT PHYSIOLOGY 2021; 187:1856-1875. [PMID: 35235671 PMCID: PMC8644242 DOI: 10.1093/plphys/kiab330] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/23/2021] [Indexed: 05/10/2023]
Abstract
Plant plasma membrane H+-ATPases and Ca2+-ATPases maintain low cytoplasmic concentrations of H+ and Ca2+, respectively, and are essential for plant growth and development. These low concentrations allow plasma membrane H+-ATPases to function as electrogenic voltage stats, and Ca2+-ATPases as "off" mechanisms in Ca2+-based signal transduction. Although these pumps are autoregulated by cytoplasmic concentrations of H+ and Ca2+, respectively, they are also subject to exquisite regulation in response to biotic and abiotic events in the environment. A common paradigm for both types of pumps is the presence of terminal regulatory (R) domains that function as autoinhibitors that can be neutralized by multiple means, including phosphorylation. A picture is emerging in which some of the phosphosites in these R domains appear to be highly, nearly constantly phosphorylated, whereas others seem to be subject to dynamic phosphorylation. Thus, some sites might function as major switches, whereas others might simply reduce activity. Here, we provide an overview of the relevant transport systems and discuss recent advances that address their relation to external stimuli and physiological adaptations.
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Affiliation(s)
- Anja T Fuglsang
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
| | - Michael Palmgren
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
- Author for communication:
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9
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García Bossi J, Kumar K, Barberini ML, Domínguez GD, Rondón Guerrero YDC, Marino-Buslje C, Obertello M, Muschietti JP, Estevez JM. The role of P-type IIA and P-type IIB Ca2+-ATPases in plant development and growth. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1239-1248. [PMID: 31740935 DOI: 10.1093/jxb/erz521] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 11/16/2019] [Indexed: 06/10/2023]
Abstract
As sessile organisms, plants have evolved mechanisms to adapt to variable and rapidly fluctuating environmental conditions. Calcium (Ca2+) in plant cells is a versatile intracellular second messenger that is essential for stimulating short- and long-term responses to environmental stresses through changes in its concentration in the cytosol ([Ca2+]cyt). Increases in [Ca2+]cyt direct the strength and length of these stimuli. In order to terminate them, the cells must then remove the cytosolic Ca2+ against a concentration gradient, either taking it away from the cell or storing it in organelles such as the endoplasmic reticulum (ER) and/or vacuoles. Here, we review current knowledge about the biological roles of plant P-type Ca2+-ATPases as potential actors in the regulation of this cytosolic Ca2+ efflux, with a focus the IIA ER-type Ca2+-ATPases (ECAs) and the IIB autoinhibited Ca2+-ATPases (ACAs). While ECAs are analogous proteins to animal sarcoplasmic-endoplasmic reticulum Ca2+-ATPases (SERCAs), ACAs are equivalent to animal plasma membrane-type ATPases (PMCAs). We examine their expression patterns in cells exhibiting polar growth and consider their appearance during the evolution of the plant lineage. Full details of the functions and coordination of ECAs and ACAs during plant growth and development have not yet been elucidated. Our current understanding of the regulation of fluctuations in Ca2+ gradients in the cytoplasm and organelles during growth is in its infancy, but recent technological advances in Ca2+ imaging are expected to shed light on this subject.
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Affiliation(s)
- Julián García Bossi
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Dr. Héctor Torres (INGEBI-CONICET), Buenos Aires, Argentina
| | - Krishna Kumar
- Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
- Molecular Plant Biology and Biotechnology Laboratory, CSIR-Central Institute of Medicinal and Aromatic Plants Research Centre, GKVK Post, Bengaluru, India
| | - María Laura Barberini
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Dr. Héctor Torres (INGEBI-CONICET), Buenos Aires, Argentina
| | - Gabriela Díaz Domínguez
- Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | | | - Cristina Marino-Buslje
- Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - Mariana Obertello
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Dr. Héctor Torres (INGEBI-CONICET), Buenos Aires, Argentina
| | - Jorge P Muschietti
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Dr. Héctor Torres (INGEBI-CONICET), Buenos Aires, Argentina
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes, Ciudad Universitaria, Pabellón II, Buenos Aires, Argentina
| | - José M Estevez
- Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
- Centro de Biotecnología Vegetal (CBV), Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
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10
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Structural basis for activation of plasma-membrane Ca 2+-ATPase by calmodulin. Commun Biol 2018; 1:206. [PMID: 30511020 PMCID: PMC6255812 DOI: 10.1038/s42003-018-0203-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 10/26/2018] [Indexed: 01/17/2023] Open
Abstract
Plasma-membrane Ca2+-ATPases expel Ca2+ from the cytoplasm and are key regulators of Ca2+ homeostasis in eukaryotes. They are autoinhibited under low Ca2+ concentrations. Calmodulin (CaM)-binding to a unique regulatory domain releases the autoinhibition and activates the pump. However, the structural basis for this activation, including the overall structure of this calcium pump and its complex with calmodulin, is unknown. We previously determined the high-resolution structure of calmodulin in complex with the regulatory domain of the plasma-membrane Ca2+-ATPase ACA8 and revealed a bimodular mechanism of calcium control in eukaryotes. Here we show that activation of ACA8 by CaM involves large conformational changes. Combining advanced modeling of neutron scattering data acquired from stealth nanodiscs and native mass spectrometry with detailed dissection of binding constants, we present a structural model for the full-length ACA8 Ca2+ pump in its calmodulin-activated state illustrating a displacement of the regulatory domain from the core enzyme. Julius Nitsche et al. demonstrate that binding of two calmodulin molecules displaces the regulatory domain of the plasma-membrane Ca2+-ATPase ACA8 to fully activate this Ca2+ pump by relieving the autoinhibition. This work provides structural evidence for the previously proposed bimodular activation mechanism.
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11
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Demidchik V, Shabala S, Isayenkov S, Cuin TA, Pottosin I. Calcium transport across plant membranes: mechanisms and functions. THE NEW PHYTOLOGIST 2018; 220:49-69. [PMID: 29916203 DOI: 10.1111/nph.15266] [Citation(s) in RCA: 191] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 04/21/2018] [Indexed: 05/20/2023]
Abstract
Contents Summary 49 I. Introduction 49 II. Physiological and structural characteristics of plant Ca2+ -permeable ion channels 50 III. Ca2+ extrusion systems 61 IV. Concluding remarks 64 Acknowledgements 64 References 64 SUMMARY: Calcium is an essential structural, metabolic and signalling element. The physiological functions of Ca2+ are enabled by its orchestrated transport across cell membranes, mediated by Ca2+ -permeable ion channels, Ca2+ -ATPases and Ca2+ /H+ exchangers. Bioinformatics analysis has not determined any Ca2+ -selective filters in plant ion channels, but electrophysiological tests do reveal Ca2+ conductances in plant membranes. The biophysical characteristics of plant Ca2+ conductances have been studied in detail and were recently complemented by molecular genetic approaches. Plant Ca2+ conductances are mediated by several families of ion channels, including cyclic nucleotide-gated channels (CNGCs), ionotropic glutamate receptors, two-pore channel 1 (TPC1), annexins and several types of mechanosensitive channels. Key Ca2+ -mediated reactions (e.g. sensing of temperature, gravity, touch and hormones, and cell elongation and guard cell closure) have now been associated with the activities of specific subunits from these families. Structural studies have demonstrated a unique selectivity filter in TPC1, which is passable for hydrated divalent cations. The hypothesis of a ROS-Ca2+ hub is discussed, linking Ca2+ transport to ROS generation. CNGC inactivation by cytosolic Ca2+ , leading to the termination of Ca2+ signals, is now mechanistically explained. The structure-function relationships of Ca2+ -ATPases and Ca2+ /H+ exchangers, and their regulation and physiological roles are analysed.
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Affiliation(s)
- Vadim Demidchik
- Department of Horticulture, Foshan University, Foshan, 528000, China
- Department of Plant Cell Biology and Bioengineering, Biological Faculty, Belarusian State University, 4 Independence Avenue, Minsk, 220030, Belarus
- Komarov Botanical Institute, Russian Academy of Sciences, 2 Professora Popova Street, St Petersburg, 197376, Russia
| | - Sergey Shabala
- Department of Horticulture, Foshan University, Foshan, 528000, China
- Tasmanian Institute of Agriculture, University of Tasmania, Private Bag 54, Hobart, Tas, 7001, Australia
| | - Stanislav Isayenkov
- Institute of Food Biotechnology and Genomics, National Academy of Science of Ukraine, 2a Osipovskogo Street, Kyiv, 04123, Ukraine
| | - Tracey A Cuin
- Tasmanian Institute of Agriculture, University of Tasmania, Private Bag 54, Hobart, Tas, 7001, Australia
| | - Igor Pottosin
- Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Avenida 25 de julio 965, Colima, 28045, Mexico
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12
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Yu H, Yan J, Du X, Hua J. Overlapping and differential roles of plasma membrane calcium ATPases in Arabidopsis growth and environmental responses. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:2693-2703. [PMID: 29506225 PMCID: PMC5920303 DOI: 10.1093/jxb/ery073] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 02/13/2018] [Indexed: 05/21/2023]
Abstract
Plant cells have multiple plasma membrane (PM)-localized calcium ATPases (ACAs) pumping calcium ions out of the cytosol. Although the involvement of some of these ACAs in plant growth and immunity has been reported, their individual and combined functions have not been fully examined. Here, we analysed the effects of single and combined mutations of four ACA genes, ACA8, ACA10, ACA12, and ACA13, in a number of processes. We found that these four genes had both overlapping and differential involvements in vegetative growth, inflorescence growth, seeds setting, disease resistance and stomatal movement. Disruption of any of these four genes reduces seed setting, indicating their contribution to the overall fitness of the plants. While ACA10 and ACA8 play major roles in vegetative growth and immunity, ACA13 and ACA12 are also involved in these processes especially when the function of ACA10 and/or ACA8 is compromised. The loss of ACA13 and ACA10 function in combination with a reduction in function of ACA8 leads to seedling death at bolting, revealing the essential role of their collective function in plant growth. Taken together, this study indicates a highly tuned calcium system involving these PM-localized calcium pumps in plant growth and environmental responses.
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Affiliation(s)
- Huiyun Yu
- Research Center of Organic Agriculture Technology, College of Plant Protection, China Agricultural University, Beijing, PR China
- School of Integrative Plant Science, Plant Biology Section, Cornell University, Ithaca, NY, USA
| | - Jiapei Yan
- School of Integrative Plant Science, Plant Biology Section, Cornell University, Ithaca, NY, USA
| | - Xiangge Du
- Research Center of Organic Agriculture Technology, College of Plant Protection, China Agricultural University, Beijing, PR China
- Correspondence: ,
| | - Jian Hua
- School of Integrative Plant Science, Plant Biology Section, Cornell University, Ithaca, NY, USA
- Correspondence: ,
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13
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Astegno A, Bonza MC, Vallone R, La Verde V, D'Onofrio M, Luoni L, Molesini B, Dominici P. Arabidopsis calmodulin-like protein CML36 is a calcium (Ca 2+) sensor that interacts with the plasma membrane Ca 2+-ATPase isoform ACA8 and stimulates its activity. J Biol Chem 2017; 292:15049-15061. [PMID: 28726644 PMCID: PMC5592680 DOI: 10.1074/jbc.m117.787796] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/07/2017] [Indexed: 11/06/2022] Open
Abstract
Calmodulin-like (CML) proteins are major EF-hand-containing, calcium (Ca2+)-binding proteins with crucial roles in plant development and in coordinating plant stress tolerance. Given their abundance in plants, the properties of Ca2+ sensors and identification of novel target proteins of CMLs deserve special attention. To this end, we recombinantly produced and biochemically characterized CML36 from Arabidopsis thaliana We analyzed Ca2+ and Mg2+ binding to the individual EF-hands, observed metal-induced conformational changes, and identified a physiologically relevant target. CML36 possesses two high-affinity Ca2+/Mg2+ mixed binding sites and two low-affinity Ca2+-specific sites. Binding of Ca2+ induced an increase in the α-helical content and a conformational change that lead to the exposure of hydrophobic regions responsible for target protein recognition. Cation binding, either Ca2+ or Mg2+, stabilized the secondary and tertiary structures of CML36, guiding a large structural transition from a molten globule apo-state to a compact holoconformation. Importantly, through in vitro binding and activity assays, we showed that CML36 interacts directly with the regulative N terminus of the Arabidopsis plasma membrane Ca2+-ATPase isoform 8 (ACA8) and that this interaction stimulates ACA8 activity. Gene expression analysis revealed that CML36 and ACA8 are co-expressed mainly in inflorescences. Collectively, our results support a role for CML36 as a Ca2+ sensor that binds to and modulates ACA8, uncovering a possible involvement of the CML protein family in the modulation of plant-autoinhibited Ca2+ pumps.
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Affiliation(s)
- Alessandra Astegno
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
| | - Maria Cristina Bonza
- the Department of Biosciences, University of Milano, Via Celoria 26, 20133 Milano, Italy
| | - Rosario Vallone
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
| | - Valentina La Verde
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
| | - Mariapina D'Onofrio
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
| | - Laura Luoni
- the Department of Biosciences, University of Milano, Via Celoria 26, 20133 Milano, Italy
| | - Barbara Molesini
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
| | - Paola Dominici
- From the Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy and
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14
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Costa A, Luoni L, Marrano CA, Hashimoto K, Köster P, Giacometti S, De Michelis MI, Kudla J, Bonza MC. Ca2+-dependent phosphoregulation of the plasma membrane Ca2+-ATPase ACA8 modulates stimulus-induced calcium signatures. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3215-3230. [PMID: 28531251 PMCID: PMC5853299 DOI: 10.1093/jxb/erx162] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/26/2017] [Indexed: 05/19/2023]
Abstract
Ca2+ signals are transient, hence, upon a stimulus-induced increase in cytosolic Ca2+ concentration, cells have to re-establish resting Ca2+ levels. Ca2+ extrusion is operated by a wealth of transporters, such as Ca2+ pumps and Ca2+/H+ antiporters, which often require a rise in Ca2+ concentration to be activated. Here, we report a regulatory fine-tuning mechanism of the Arabidopsis thaliana plasma membrane-localized Ca2+-ATPase isoform ACA8 that is mediated by calcineurin B-like protein (CBL) and CBL-interacting protein kinase (CIPK) complexes. We show that two CIPKs (CIPK9 and CIPK14) are able to interact with ACA8 in vivo and phosphorylate it in vitro. Transient co-overexpression of ACA8 with CIPK9 and the plasma membrane Ca2+ sensor CBL1 in tobacco leaf cells influences nuclear Ca2+ dynamics, specifically reducing the height of the second peak of the wound-induced Ca2+ transient. Stimulus-induced Ca2+ transients in mature leaves and seedlings of an aca8 T-DNA insertion line exhibit altered dynamics when compared with the wild type. Altogether our results identify ACA8 as a prominent in vivo regulator of cellular Ca2+ dynamics and reveal the existence of a Ca2+-dependent CBL-CIPK-mediated regulatory feedback mechanism, which crucially functions in the termination of Ca2+ signals.
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Affiliation(s)
- Alex Costa
- Department of Biosciences, University of Milan, Milan, Italy
- Institute of Biophysics, Consiglio Nazionale delle Ricerche, Milan, Italy
| | - Laura Luoni
- Department of Biosciences, University of Milan, Milan, Italy
| | | | - Kenji Hashimoto
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Münster, Germany
| | - Philipp Köster
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Münster, Germany
| | | | - Maria Ida De Michelis
- Department of Biosciences, University of Milan, Milan, Italy
- Institute of Biophysics, Consiglio Nazionale delle Ricerche, Milan, Italy
| | - Jörg Kudla
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Münster, Germany
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15
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Xu L, Wang A, Wang J, Wei Q, Zhang W. Piriformospora indica confers drought tolerance on Zea mays L. through enhancement of antioxidant activity and expression of drought-related genes. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.cj.2016.10.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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The Plasma Membrane Calcium Pump (PMCA): Regulation of Cytosolic Ca2+, Genetic Diversities and Its Role in Sub-plasma Membrane Microdomains. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:3-21. [DOI: 10.1007/978-3-319-55858-5_1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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17
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Calì T, Frizzarin M, Luoni L, Zonta F, Pantano S, Cruz C, Bonza MC, Bertipaglia I, Ruzzene M, De Michelis MI, Damiano N, Marin O, Zanni G, Zanotti G, Brini M, Lopreiato R, Carafoli E. The ataxia related G1107D mutation of the plasma membrane Ca 2+ ATPase isoform 3 affects its interplay with calmodulin and the autoinhibition process. Biochim Biophys Acta Mol Basis Dis 2016; 1863:165-173. [PMID: 27632770 DOI: 10.1016/j.bbadis.2016.09.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/05/2016] [Accepted: 09/09/2016] [Indexed: 11/20/2022]
Abstract
The plasma membrane Ca2+ ATPases (PMCA pumps) have a long, cytosolic C-terminal regulatory region where a calmodulin-binding domain (CaM-BD) is located. Under basal conditions (low Ca2+), the C-terminal tail of the pump interacts with autoinhibitory sites proximal to the active center of the enzyme. In activating conditions (i.e., high Ca2+), Ca2+-bound CaM displaces the C-terminal tail from the autoinhibitory sites, restoring activity. We have recently identified a G1107D replacement within the CaM-BD of isoform 3 of the PMCA pump in a family affected by X-linked congenital cerebellar ataxia. Here, we investigate the effects of the G1107D replacement on the interplay of the mutated CaM-BD with both CaM and the pump core, by combining computational, biochemical and functional approaches. We provide evidence that the affinity of the isolated mutated CaM-BD for CaM is significantly reduced with respect to the wild type (wt) counterpart, and that the ability of CaM to activate the pump in vitro is thus decreased. Multiscale simulations support the conclusions on the detrimental effect of the mutation, indicating reduced stability of the CaM binding. We further show that the G1107D replacement impairs the autoinhibition mechanism of the PMCA3 pump as well, as the introduction of a negative charge perturbs the contacts between the CaM-BD and the pump core. Thus, the mutation affects both the ability of the pump to optimally transport Ca2+ in the activated state, and the autoinhibition mechanism in its resting state.
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Affiliation(s)
- Tito Calì
- Department of Biomedical Sciences, University of Padova, Italy
| | | | - Laura Luoni
- Department of Biosciences, University of Milano, Italy
| | - Francesco Zonta
- Shanghai Institute of Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, China
| | | | - Carlos Cruz
- Aggeu Magalhães Research Center - CpqAM, Oswaldo Cruz Foundation - FioCruz, Rio de Janeiro, Brazil; Institut Pasteur de Montevideo, Uruguay
| | | | | | - Maria Ruzzene
- Department of Biomedical Sciences, University of Padova, Italy
| | | | - Nunzio Damiano
- Department of Biomedical Sciences, University of Padova, Italy
| | - Oriano Marin
- Department of Biomedical Sciences, University of Padova, Italy
| | - Ginevra Zanni
- Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Marisa Brini
- Department of Biology, University of Padova, Italy
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18
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Wang F, Chen ZH, Liu X, Colmer TD, Zhou M, Shabala S. Tissue-specific root ion profiling reveals essential roles of the CAX and ACA calcium transport systems in response to hypoxia in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3747-62. [PMID: 26889007 PMCID: PMC4896357 DOI: 10.1093/jxb/erw034] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Waterlogging is a major abiotic stress that limits the growth of plants. The crucial role of Ca(2+) as a second messenger in response to abiotic and biotic stimuli has been widely recognized in plants. However, the physiological and molecular mechanisms of Ca(2+) distribution within specific cell types in different root zones under hypoxia is poorly understood. In this work, whole-plant physiological and tissue-specific Ca(2+) changes were studied using several ACA (Ca(2+)-ATPase) and CAX (Ca(2+)/proton exchanger) knock-out Arabidopsis mutants subjected to waterlogging treatment. In the wild-type (WT) plants, several days of hypoxia decreased the expression of ACA8, CAX4, and CAX11 by 33% and 50% compared with the control. The hypoxic treatment also resulted in an up to 11-fold tissue-dependent increase in Ca(2+) accumulation in root tissues as revealed by confocal microscopy. The increase was much higher in stelar cells in the mature zone of Arabidopsis mutants with loss of function for ACA8, ACA11, CAX4, and CAX11 In addition, a significantly increased Ca(2+) concentration was found in the cytosol of stelar cells in the mature zone after hypoxic treatment. Three weeks of waterlogging resulted in dramatic loss of shoot biomass in cax11 plants (67% loss in shoot dry weight), while in the WT and other transport mutants this decline was only 14-22%. These results were also consistent with a decline in leaf chlorophyll fluorescence (F v/F m). It is suggested that CAX11 plays a key role in maintaining cytosolic Ca(2+) homeostasis and/or signalling in root cells under hypoxic conditions.
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Affiliation(s)
- Feifei Wang
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Zhong-Hua Chen
- School of Science and Health, Western Sydney University, Penrith NSW2751, Australia
| | - Xiaohui Liu
- School of Science and Health, Western Sydney University, Penrith NSW2751, Australia School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Timothy David Colmer
- School of Plant Biology and Institute of Agriculture, The University of Western Australia, Crawley, WA 6009, Australia
| | - Meixue Zhou
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Hobart, Tasmania 7001, Australia
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19
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Figueroa KP, Paul S, Calì T, Lopreiato R, Karan S, Frizzarin M, Ames D, Zanni G, Brini M, Dansithong W, Milash B, Scoles DR, Carafoli E, Pulst SM. Spontaneous shaker rat mutant - a new model for X-linked tremor/ataxia. Dis Model Mech 2016; 9:553-62. [PMID: 27013529 PMCID: PMC4892658 DOI: 10.1242/dmm.022848] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 02/29/2016] [Indexed: 12/18/2022] Open
Abstract
The shaker rat is an X-linked recessive spontaneous model of progressive Purkinje cell (PC) degeneration exhibiting a shaking ataxia and wide stance. Generation of Wistar Furth (WF)/Brown Norwegian (BN) F1 hybrids and genetic mapping of F2 sib-sib offspring using polymorphic markers narrowed the candidate gene region to 26 Mbp denoted by the last recombinant genetic marker DXRat21 at 133 Mbp to qter (the end of the long arm). In the WF background, the shaker mutation has complete penetrance, results in a stereotypic phenotype and there is a narrow window for age of disease onset; by contrast, the F2 hybrid phenotype was more varied, with a later age of onset and likely non-penetrance of the mutation. By deep RNA-sequencing, five variants were found in the candidate region; four were novel without known annotation. One of the variants caused an arginine (R) to cysteine (C) change at codon 35 of the ATPase, Ca2+ transporting, plasma membrane 3 (Atp2b3) gene encoding PMCA3 that has high expression in the cerebellum. The variant was well supported by hundreds of overlapping reads, and was found in 100% of all affected replicas and 0% of the wild-type (WT) replicas. The mutation segregated with disease in all affected animals and the amino acid change was found in an evolutionarily conserved region of PMCA3. Despite strong genetic evidence for pathogenicity, in vitro analyses of PMCA3R35C function did not show any differences to WT PMCA3. Because Atp2b3 mutation leads to congenital ataxia in humans, the identified Atp2b3 missense change in the shaker rat presents a good candidate for the shaker rat phenotype based on genetic criteria, but cannot yet be considered a definite pathogenic variant owing to lack of functional changes. Summary: The shaker rat mutant: a new model for essential tremors and ataxia characterized by Purkinje cell degeneration.
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Affiliation(s)
- Karla P Figueroa
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Tito Calì
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | | | - Sukanya Karan
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Martina Frizzarin
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Darren Ames
- Bioinformatics Shared Resource, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Ginevra Zanni
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marisa Brini
- Department of Biology, University of Padova, Padova, Italy
| | - Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Brett Milash
- Bioinformatics Shared Resource, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | | | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
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20
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Calì T, Lopreiato R, Shimony J, Vineyard M, Frizzarin M, Zanni G, Zanotti G, Brini M, Shinawi M, Carafoli E. A Novel Mutation in Isoform 3 of the Plasma Membrane Ca2+ Pump Impairs Cellular Ca2+ Homeostasis in a Patient with Cerebellar Ataxia and Laminin Subunit 1α Mutations. J Biol Chem 2015; 290:16132-41. [PMID: 25953895 DOI: 10.1074/jbc.m115.656496] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Indexed: 11/06/2022] Open
Abstract
The particular importance of Ca(2+) signaling to neurons demands its precise regulation within their cytoplasm. Isoform 3 of the plasma membrane Ca(2+) ATPase (the PMCA3 pump), which is highly expressed in brain and cerebellum, plays an important role in the regulation of neuronal Ca(2+). A genetic defect of the PMCA3 pump has been described in one family with X-linked congenital cerebellar ataxia. Here we describe a novel mutation in the ATP2B3 gene in a patient with global developmental delay, generalized hypotonia and cerebellar ataxia. The mutation (a R482H replacement) impairs the Ca(2+) ejection function of the pump. It reduces the ability of the pump expressed in model cells to control Ca(2+) transients generated by cell stimulation and impairs its Ca(2+) extrusion function under conditions of low resting cytosolic Ca(2+) as well. In silico analysis of the structural effect of the mutation suggests a reduced stabilization of the portion of the pump surrounding the mutated residue in the Ca(2+)-bound state. The patient also carries two missense mutations in LAMA1, encoding laminin subunit 1α. On the basis of the family pedigree of the patient, the presence of both PMCA3 and laminin subunit 1α mutations appears to be necessary for the development of the disease. Considering the observed defect in cellular Ca(2+) homeostasis and the previous finding that PMCAs act as digenic modulators in Ca(2+)-linked pathologies, the PMCA3 dysfunction along with LAMA1 mutations could act synergistically to cause the neurological phenotype.
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Affiliation(s)
| | | | | | - Marisa Vineyard
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University School of Medicine, St. Louis, Missouri 63110-1093
| | | | - Ginevra Zanni
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), 00165 Rome, Italy, and
| | | | | | - Marwan Shinawi
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University School of Medicine, St. Louis, Missouri 63110-1093,
| | - Ernesto Carafoli
- Venetian Institute of Molecular Medicine (VIMM), 35131 Padova, Italy
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21
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Limonta M, Romanowsky S, Olivari C, Bonza MC, Luoni L, Rosenberg A, Harper JF, De Michelis MI. ACA12 is a deregulated isoform of plasma membrane Ca²⁺-ATPase of Arabidopsis thaliana. PLANT MOLECULAR BIOLOGY 2014; 84:387-97. [PMID: 24101142 PMCID: PMC4104672 DOI: 10.1007/s11103-013-0138-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 09/29/2013] [Indexed: 05/08/2023]
Abstract
Plant auto-inhibited Ca²⁺-ATPases (ACA) are crucial in defining the shape of calcium transients and therefore in eliciting plant responses to various stimuli. Arabidopsis thaliana genome encodes ten ACA isoforms that can be divided into four clusters based on gene structure and sequence homology. While isoforms from clusters 1, 2 and 4 have been characterized, virtually nothing is known about members of cluster 3 (ACA12 and ACA13). Here we show that a GFP-tagged ACA12 localizes at the plasma membrane and that expression of ACA12 rescues the phenotype of partial male sterility of a null mutant of the plasma membrane isoform ACA9, thus providing genetic evidence that ACA12 is a functional plasma membrane-resident Ca²⁺-ATPase. By ACA12 expression in yeast and purification by CaM-affinity chromatography, we show that, unlike other ACAs, the activity of ACA12 is not stimulated by CaM. Moreover, full length ACA12 is able to rescue a yeast mutant deficient in calcium pumps. Analysis of single point ACA12 mutants suggests that ACA12 loss of auto-inhibition can be ascribed to the lack of two acidic residues--highly conserved in other ACA isoforms--localized at the cytoplasmic edge of the second and third transmembrane segments. Together, these results support a model in which the calcium pump activity of ACA12 is primarily regulated by increasing or decreasing mRNA expression and/or protein translation and degradation.
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Affiliation(s)
- Margherita Limonta
- Dipartimento di Bioscienze, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, via G. Celoria 26, 20133 Milano, Italy
| | - Shawn Romanowsky
- Biochemistry Department, University of Nevada, Reno, Nevada 89557
| | - Claudio Olivari
- Dipartimento di Bioscienze, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, via G. Celoria 26, 20133 Milano, Italy
| | - Maria Cristina Bonza
- Dipartimento di Bioscienze, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, via G. Celoria 26, 20133 Milano, Italy
| | - Laura Luoni
- Dipartimento di Bioscienze, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, via G. Celoria 26, 20133 Milano, Italy
| | - Alexa Rosenberg
- Biochemistry Department, University of Nevada, Reno, Nevada 89557
| | | | - Maria Ida De Michelis
- Dipartimento di Bioscienze, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, via G. Celoria 26, 20133 Milano, Italy
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22
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Huda KMK, Banu MSA, Tuteja R, Tuteja N. Global calcium transducer P-type Ca²⁺-ATPases open new avenues for agriculture by regulating stress signalling. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:3099-109. [PMID: 23918957 DOI: 10.1093/jxb/ert182] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Food security is in danger under the continuous growing threat of various stresses including climate change and global warming, which ultimately leads to a reduction in crop yields. Calcium plays a very important role in many signal transduction pathways including stress signalling. Different extracellular stimuli trigger increases in cytosolic calcium, which is detrimental to plants. To cope with such stresses, plants need to develop efficient efflux mechanisms to maintain ionic homeostasis. The Ca(2+)-ATPases are members of the P-type ATPase superfamily, which perform many fundamental processes in organisms by actively transporting ions across cellular membranes. In recent years, many studies have revealed that, as well as efflux mechanisms, Ca(2+)-ATPases also play critical roles in sensing calcium fluctuations and relaying downstream signals by activating definitive targets, thus modulating corresponding metabolic pathways. As calcium-activated calmodulin (CaM) is reported to play vital roles in stress tolerance, the presence of a unique CaM-binding site in type IIB Ca(2+)-ATPases indicates their potential role in biotic as well as abiotic stress tolerance. The key roles of Ca(2+)-ATPases in transport systems and stress signalling in cellular homeostasis are addressed in this review. A complete understanding of plant defence mechanisms under stress will allow bioengineering of improved crop plants, which will be crucial for food security currently observed worldwide in the context of global climate changes. Overall, this article covers classification, evolution, structural aspects of Ca(2+)-ATPases, and their emerging roles in plant stress signalling.
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Affiliation(s)
- Kazi Md Kamrul Huda
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
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23
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A bimodular mechanism of calcium control in eukaryotes. Nature 2012; 491:468-72. [PMID: 23086147 DOI: 10.1038/nature11539] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 08/23/2012] [Indexed: 11/08/2022]
Abstract
Calcium ions (Ca(2+)) have an important role as secondary messengers in numerous signal transduction processes, and cells invest much energy in controlling and maintaining a steep gradient between intracellular (∼0.1-micromolar) and extracellular (∼2-millimolar) Ca(2+) concentrations. Calmodulin-stimulated calcium pumps, which include the plasma-membrane Ca(2+)-ATPases (PMCAs), are key regulators of intracellular Ca(2+) in eukaryotes. They contain a unique amino- or carboxy-terminal regulatory domain responsible for autoinhibition, and binding of calcium-loaded calmodulin to this domain releases autoinhibition and activates the pump. However, the structural basis for the activation mechanism is unknown and a key remaining question is how calmodulin-mediated PMCA regulation can cover both basal Ca(2+) levels in the nanomolar range as well as micromolar-range Ca(2+) transients generated by cell stimulation. Here we present an integrated study combining the determination of the high-resolution crystal structure of a PMCA regulatory-domain/calmodulin complex with in vivo characterization and biochemical, biophysical and bioinformatics data that provide mechanistic insights into a two-step PMCA activation mechanism mediated by calcium-loaded calmodulin. The structure shows the entire PMCA regulatory domain and reveals an unexpected 2:1 stoichiometry with two calcium-loaded calmodulin molecules binding to different sites on a long helix. A multifaceted characterization of the role of both sites leads to a general structural model for calmodulin-mediated regulation of PMCAs that allows stringent, highly responsive control of intracellular calcium in eukaryotes, making it possible to maintain a stable, basal level at a threshold Ca(2+) concentration, where steep activation occurs.
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24
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Chen Y, Liu P, Hoehenwarter W, Lin J. Proteomic and Phosphoproteomic Analysis of Picea wilsonii Pollen Development under Nutrient Limitation. J Proteome Res 2012; 11:4180-90. [DOI: 10.1021/pr300295m] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yanmei Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College
of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Peng Liu
- Key Laboratory of Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Wolfgang Hoehenwarter
- Department Molecular Systems Biology, University of Vienna, Faculty of Life Sciences, Althanstrasse
14, A-1090, Vienna
| | - Jinxing Lin
- Key Laboratory of Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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25
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Sørensen DM, Møller AB, Jakobsen MK, Jensen MK, Vangheluwe P, Buch-Pedersen MJ, Palmgren MG. Ca2+ induces spontaneous dephosphorylation of a novel P5A-type ATPase. J Biol Chem 2012; 287:28336-48. [PMID: 22730321 DOI: 10.1074/jbc.m112.387191] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
P5 ATPases constitute the least studied group of P-type ATPases, an essential family of ion pumps in all kingdoms of life. Although P5 ATPases are present in every eukaryotic genome analyzed so far, they have remained orphan pumps, and their biochemical function is obscure. We show that a P5A ATPase from barley, HvP5A1, locates to the endoplasmic reticulum and is able to rescue knock-out mutants of P5A genes in both Arabidopsis thaliana and Saccharomyces cerevisiae. HvP5A1 spontaneously forms a phosphorylated reaction cycle intermediate at the catalytic residue Asp-488, whereas, among all plant nutrients tested, only Ca(2+) triggers dephosphorylation. Remarkably, Ca(2+)-induced dephosphorylation occurs at high apparent [Ca(2+)] (K(i) = 0.25 mM) and is independent of the phosphatase motif of the pump and the putative binding site for transported ligands located in M4. Taken together, our results rule out that Ca(2+) is a transported substrate but indicate the presence of a cytosolic low affinity Ca(2+)-binding site, which is conserved among P-type pumps and could be involved in pump regulation. Our work constitutes the first characterization of a P5 ATPase phosphoenzyme and points to Ca(2+) as a modifier of its function.
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Affiliation(s)
- Danny Mollerup Sørensen
- Centre for Membrane Pumps in Cells and Disease, PUMPKIN, Danish National Research Foundation, Department of Plant Biology and Biotechnology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
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Giacometti S, Marrano CA, Bonza MC, Luoni L, Limonta M, De Michelis MI. Phosphorylation of serine residues in the N-terminus modulates the activity of ACA8, a plasma membrane Ca2+-ATPase of Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:1215-24. [PMID: 22090438 PMCID: PMC3276087 DOI: 10.1093/jxb/err346] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 09/20/2011] [Accepted: 10/04/2011] [Indexed: 05/23/2023]
Abstract
ACA8 is a plasma membrane-localized isoform of calmodulin (CaM)-regulated Ca(2+)-ATPase of Arabidopsis thaliana. Several phosphopeptides corresponding to portions of the regulatory N-terminus of ACA8 have been identified in phospho-proteomic studies. To mimic phosphorylation of the ACA8 N-terminus, each of the serines found to be phosphorylated in those studies (Ser19, Ser22, Ser27, Ser29, Ser57, and Ser99) has been mutated to aspartate. Mutants have been expressed in Saccharomyces cerevisiae and characterized: mutants S19D and S57D--and to a lesser extent also mutants S22D and S27D--are deregulated, as shown by their low activation by CaM and by tryptic cleavage of the N-terminus. The His-tagged N-termini of wild-type and mutant ACA8 (6His-(1)M-I(116)) were expressed in Escherichia coli, affinity-purified, and used to analyse the kinetics of CaM binding by surface plasmon resonance. All the analysed mutations affect the kinetics of interaction with CaM to some extent: in most cases, the altered kinetics result in marginal changes in affinity, with the exception of mutants S57D (K(D) ≈ 10-fold higher than wild-type ACA8) and S99D (K(D) about half that of wild-type ACA8). The ACA8 N-terminus is phosphorylated in vitro by two isoforms of A. thaliana calcium-dependent protein kinase (CPK1 and CPK16); phosphorylation of mutant 6His-(1)M-I(116) peptides shows that CPK16 is able to phosphorylate the ACA8 N-terminus at Ser19 and at Ser22. The possible physiological implications of the subtle modulation of ACA8 activity by phosphorylation of its N-terminus are discussed.
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Pedersen CNS, Axelsen KB, Harper JF, Palmgren MG. Evolution of plant p-type ATPases. FRONTIERS IN PLANT SCIENCE 2012; 3:31. [PMID: 22629273 PMCID: PMC3355532 DOI: 10.3389/fpls.2012.00031] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Accepted: 01/28/2012] [Indexed: 05/18/2023]
Abstract
Five organisms having completely sequenced genomes and belonging to all major branches of green plants (Viridiplantae) were analyzed with respect to their content of P-type ATPases encoding genes. These were the chlorophytes Ostreococcus tauri and Chlamydomonas reinhardtii, and the streptophytes Physcomitrella patens (a non-vascular moss), Selaginella moellendorffii (a primitive vascular plant), and Arabidopsis thaliana (a model flowering plant). Each organism contained sequences for all five subfamilies of P-type ATPases. Whereas Na(+) and H(+) pumps seem to mutually exclude each other in flowering plants and animals, they co-exist in chlorophytes, which show representatives for two kinds of Na(+) pumps (P2C and P2D ATPases) as well as a primitive H(+)-ATPase. Both Na(+) and H(+) pumps also co-exist in the moss P. patens, which has a P2D Na(+)-ATPase. In contrast to the primitive H(+)-ATPases in chlorophytes and P. patens, the H(+)-ATPases from vascular plants all have a large C-terminal regulatory domain as well as a conserved Arg in transmembrane segment 5 that is predicted to function as part of a backflow protection mechanism. Together these features are predicted to enable H(+) pumps in vascular plants to create large electrochemical gradients that can be modulated in response to diverse physiological cues. The complete inventory of P-type ATPases in the major branches of Viridiplantae is an important starting point for elucidating the evolution in plants of these important pumps.
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Affiliation(s)
- Christian N. S. Pedersen
- Center for Membrane Pumps in Cells and Disease – PUMPKIN, Danish National Research Foundation, Aarhus UniversityAarhus, Denmark
- Bioinformatics Research Centre (BiRC), Faculty of Science and Technology, Aarhus UniversityAarhus, Denmark
| | - Kristian B. Axelsen
- Department of Plant Biology and Biotechnology, Faculty of Life Sciences, Center for Membrane Pumps in Cells and Disease – PUMPKIN, Danish National Research Foundation, University of CopenhagenFrederiksberg C, Denmark
- Swiss-Prot Group, Swiss Institute of BioinformaticsGeneva, Switzerland
| | - Jeffrey F. Harper
- Department of Biochemistry and Molecular Biology, University of NevadaReno, NV, USA
| | - Michael G. Palmgren
- Department of Plant Biology and Biotechnology, Faculty of Life Sciences, Center for Membrane Pumps in Cells and Disease – PUMPKIN, Danish National Research Foundation, University of CopenhagenFrederiksberg C, Denmark
- *Correspondence: Michael G. Palmgren, Department of Plant Biology and Biotechnology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark. e-mail:
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Bose J, Pottosin II, Shabala SS, Palmgren MG, Shabala S. Calcium efflux systems in stress signaling and adaptation in plants. FRONTIERS IN PLANT SCIENCE 2011; 2:85. [PMID: 22639615 PMCID: PMC3355617 DOI: 10.3389/fpls.2011.00085] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 11/04/2011] [Indexed: 05/18/2023]
Abstract
Transient cytosolic calcium ([Ca(2+)](cyt)) elevation is an ubiquitous denominator of the signaling network when plants are exposed to literally every known abiotic and biotic stress. These stress-induced [Ca(2+)](cyt) elevations vary in magnitude, frequency, and shape, depending on the severity of the stress as well the type of stress experienced. This creates a unique stress-specific calcium "signature" that is then decoded by signal transduction networks. While most published papers have been focused predominantly on the role of Ca(2+) influx mechanisms to shaping [Ca(2+)](cyt) signatures, restoration of the basal [Ca(2+)](cyt) levels is impossible without both cytosolic Ca(2+) buffering and efficient Ca(2+) efflux mechanisms removing excess Ca(2+) from cytosol, to reload Ca(2+) stores and to terminate Ca(2+) signaling. This is the topic of the current review. The molecular identity of two major types of Ca(2+) efflux systems, Ca(2+)-ATPase pumps and Ca(2+)/H(+) exchangers, is described, and their regulatory modes are analyzed in detail. The spatial and temporal organization of calcium signaling networks is described, and the importance of existence of intracellular calcium microdomains is discussed. Experimental evidence for the role of Ca(2+) efflux systems in plant responses to a range of abiotic and biotic factors is summarized. Contribution of Ca(2+)-ATPase pumps and Ca(2+)/H(+) exchangers in shaping [Ca(2+)](cyt) signatures is then modeled by using a four-component model (plasma- and endo-membrane-based Ca(2+)-permeable channels and efflux systems) taking into account the cytosolic Ca(2+) buffering. It is concluded that physiologically relevant variations in the activity of Ca(2+)-ATPase pumps and Ca(2+)/H(+) exchangers are sufficient to fully describe all the reported experimental evidence and determine the shape of [Ca(2+)](cyt) signatures in response to environmental stimuli, emphasizing the crucial role these active efflux systems play in plant adaptive responses to environment.
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Affiliation(s)
- Jayakumar Bose
- School of Agricultural Science, University of TasmaniaHobart, TAS, Australia
| | - Igor I. Pottosin
- Centro Universitario de Investigaciones Biomédicas, Universidad de ColimaColima, México
| | | | | | - Sergey Shabala
- School of Agricultural Science, University of TasmaniaHobart, TAS, Australia
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Bonza MC, De Michelis MI. The plant Ca2+ -ATPase repertoire: biochemical features and physiological functions. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13:421-30. [PMID: 21489092 DOI: 10.1111/j.1438-8677.2010.00405.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Ca(2+)-ATPases are P-type ATPases that use the energy of ATP hydrolysis to pump Ca(2+) from the cytoplasm into intracellular compartments or into the apoplast. Plant cells possess two types of Ca(2+) -pumping ATPase, named ECAs (for ER-type Ca(2+)-ATPase) and ACAs (for auto-inhibited Ca(2+)-ATPase). Each type comprises different isoforms, localised on different membranes. Here, we summarise available knowledge of the biochemical characteristics and the physiological role of plant Ca(2+)-ATPases, greatly improved after gene identification, which allows both biochemical analysis of single isoforms through heterologous expression in yeast and expression profiling and phenotypic analysis of single isoform knock-out mutants.
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Affiliation(s)
- M C Bonza
- Dipartimento di Biologia L. Gorini, Università degli Studi di Milano, Istituto di Biofisica del CNR, Sezione di Milano, Milano, Italy
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Shabala S, Baekgaard L, Shabala L, Fuglsang A, Babourina O, Palmgren MG, Cuin TA, Rengel Z, Nemchinov LG. Plasma membrane Ca²+ transporters mediate virus-induced acquired resistance to oxidative stress. PLANT, CELL & ENVIRONMENT 2011; 34:406-17. [PMID: 21062316 DOI: 10.1111/j.1365-3040.2010.02251.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
This paper reports the phenomenon of acquired cross-tolerance to oxidative stress in plants and investigates the activity of specific Ca²+ transport systems mediating this phenomenon. Nicotiana benthamiana plants were infected with Potato virus X (PVX) and exposed to oxidative [either ultraviolet (UV-C) or H₂O₂] stress. Plant adaptive responses were assessed by the combined application of a range of electrophysiological (non-invasive microelectrode ion flux measurements), biochemical (Ca²+- and H+-ATPase activity), imaging (fluorescence lifetime imaging measurements of changes in intracellular Ca²+ concentrations), pharmacological and cytological transmission electrone microscopy techniques. Virus-infected plants had a better ability to control UV-induced elevations in cytosolic-free Ca²+ and prevent structural and functional damage of chloroplasts. Taken together, our results suggest a high degree of crosstalk between UV and pathogen-induced oxidative stresses, and highlight the crucial role of Ca²+ efflux systems in acquired resistance to oxidative stress in plants.
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Affiliation(s)
- Sergey Shabala
- School of Agricultural Science, Menzies Research Institute, University of Tasmania, Private Bag 54, Hobart, Tas 7001, Australia.
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31
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Ca2+ Pumps and Ca2+ Antiporters in Plant Development. SIGNALING AND COMMUNICATION IN PLANTS 2011. [DOI: 10.1007/978-3-642-14369-4_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
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32
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Palmgren MG, Bækgaard L, López-Marqués RL, Fuglsang AT. Plasma Membrane ATPases. THE PLANT PLASMA MEMBRANE 2011. [DOI: 10.1007/978-3-642-13431-9_7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Ishida H, Vogel HJ. The solution structure of a plant calmodulin and the CaM-binding domain of the vacuolar calcium-ATPase BCA1 reveals a new binding and activation mechanism. J Biol Chem 2010; 285:38502-10. [PMID: 20880850 PMCID: PMC2992282 DOI: 10.1074/jbc.m110.131201] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 08/09/2010] [Indexed: 11/06/2022] Open
Abstract
The type IIb class of plant Ca(2+)-ATPases contains a unique N-terminal extension that encompasses a calmodulin (CaM) binding domain and an auto-inhibitory domain. Binding of Ca(2+)-CaM to this region can release auto-inhibition and activates the calcium pump. Using multidimensional NMR spectroscopy, we have determined the solution structure of the complex of a plant CaM isoform with the CaM-binding domain of the well characterized Ca(2+)-ATPase BCA1 from cauliflower. The complex has a rather elongated structure in which the two lobes of CaM do not contact each other. The anchor residues Trp-23 and Ile-40 form a 1-8-18 interaction motif. Binding of Ca(2+)-CaM gives rise to the induction of two helical parts in this unique target peptide. The two helical portions are connected by a highly positively charged bend region, which represents a relatively fixed angle and positions the two lobes of CaM in an orientation that has not been seen before in any complex structure of calmodulin. The behavior of the complex was further characterized by heteronuclear NMR dynamics measurements of the isotope-labeled protein and peptide. These data suggest a unique calcium-driven activation mechanism for BCA1 and other plant Ca(2+)-ATPases that may also explain the action of calcium-CaM on some other target enzymes. Moreover, CaM activation of plant Ca(2+)-ATPases seems to occur in an organelle-specific manner.
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Affiliation(s)
- Hiroaki Ishida
- From the Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Hans J. Vogel
- From the Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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34
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Bonza MC, Luoni L. Plant and animal type 2B Ca2+-ATPases: evidence for a common auto-inhibitory mechanism. FEBS Lett 2010; 584:4783-8. [PMID: 21073872 DOI: 10.1016/j.febslet.2010.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 11/04/2010] [Indexed: 10/18/2022]
Abstract
Plant auto-inhibited Ca(2+)-ATPase 8 (ACA8) and animal plasma membrane Ca(2+)-ATPase 4b (PMCA4b) are representatives of plant and animal 2B P-type ATPases with a regulatory auto-inhibitory domain localized at the N- and C-terminus, respectively. To check whether the regulatory domain works independently of its terminal localization and if auto-inhibitory domains of different organisms are interchangeable, a mutant in which the N-terminus of ACA8 is repositioned at the C-terminus and chimeras in which PMCA4b C-terminus is fused to the N- or C-terminus of ACA8 were analysed in the yeast mutant K616 devoid of endogenous Ca(2+)-ATPases. Results show that the regulatory function of the terminal domain is independent from its position in ACA8 and that the regulatory domain belonging to PMCA4b is able to at least partially auto-inhibit ACA8.
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35
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Chen Y, Hoehenwarter W, Weckwerth W. Comparative analysis of phytohormone-responsive phosphoproteins in Arabidopsis thaliana using TiO2-phosphopeptide enrichment and mass accuracy precursor alignment. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 63:1-17. [PMID: 20374526 DOI: 10.1111/j.1365-313x.2010.04218.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Protein phosphorylation/dephosphorylation is a central post-translational modification in plant hormone signaling, but little is known about its extent and function. Although pertinent protein kinases and phosphatases have been predicted and identified for a variety of hormone responses, classical biochemical approaches have so far revealed only a few candidate proteins and even fewer phosphorylation sites. Here we performed a global quantitative analysis of the Arabidopsis phosphoproteome in response to a time course of treatments with various plant hormones using phosphopeptide enrichment and subsequent mass accuracy precursor alignment (MAPA). The use of three time points, 1, 3 and 6 h, in combination with five phytohormone treatments, abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellic acid (GA), jasmonic acid (JA) and kinetin, resulted in 324,000 precursor ions from 54 LC-Orbitrap-MS analyses quantified and aligned in a data matrix with the dimension of 6000 x 54 using the ProtMax algorithm. To dissect the phytohormone responses, multivariate principal/independent components analysis was performed. In total, 152 phosphopeptides were identified as differentially regulated; these phosphopeptides are involved in a wide variety of signaling pathways. New phosphorylation sites were identified for ABA response element binding factors that showed a specific increase in response to ABA. New phosphorylation sites were also found for RLKs and auxin transporters. We found that different hormones regulate distinct amino acid residues of members of the same protein families. In contrast, tyrosine phosphorylation of the G alpha subunit appeared to be a common response for multiple hormones, demonstrating global cross-talk among hormone signaling pathways.
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Affiliation(s)
- Yanmei Chen
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
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36
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Bonza MC, Martin H, Kang M, Lewis G, Greiner T, Giacometti S, Van Etten JL, De Michelis MI, Thiel G, Moroni A. A functional calcium-transporting ATPase encoded by chlorella viruses. J Gen Virol 2010; 91:2620-9. [PMID: 20573858 PMCID: PMC3052600 DOI: 10.1099/vir.0.021873-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Calcium-transporting ATPases (Ca2+ pumps) are major players in maintaining calcium homeostasis in the cell and have been detected in all cellular organisms. Here, we report the identification of two putative Ca2+ pumps, M535L and C785L, encoded by chlorella viruses MT325 and AR158, respectively, and the functional characterization of M535L. Phylogenetic and sequence analyses place the viral proteins in group IIB of P-type ATPases even though they lack a typical feature of this class, a calmodulin-binding domain. A Ca2+ pump gene is present in 45 of 47 viruses tested and is transcribed during virus infection. Complementation analysis of the triple yeast mutant K616 confirmed that M535L transports calcium ions and, unusually for group IIB pumps, also manganese ions. In vitro assays show basal ATPase activity. This activity is inhibited by vanadate, but, unlike that of other Ca2+ pumps, is not significantly stimulated by either calcium or manganese. The enzyme forms a 32P-phosphorylated intermediate, which is inhibited by vanadate and not stimulated by the transported substrate Ca2+, thus confirming the peculiar properties of this viral pump. To our knowledge this is the first report of a functional P-type Ca2+-transporting ATPase encoded by a virus.
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Affiliation(s)
- Maria Cristina Bonza
- Dipartimento di Biologia e Istituto di Biofisica del CNR, Università degli Studi di Milano, Milano, Italy
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37
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Roelfsema MRG, Hedrich R. Making sense out of Ca(2+) signals: their role in regulating stomatal movements. PLANT, CELL & ENVIRONMENT 2010; 33:305-321. [PMID: 19906147 DOI: 10.1111/j.1365-3040.2009.02075.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Plant cells maintain high Ca(2+) concentration gradients between the cytosol and the extracellular matrix, as well as intracellular compartments. During evolution, the regulatory mechanisms, maintaining low cytosolic free Ca(2+) concentrations, most likely provided the backbone for the development of Ca(2+)-dependent signalling pathways. In this review, the current understanding of molecular mechanisms involved in Ca(2+) homeostasis of plants cells is evaluated. The question is addressed to which extent the mechanisms, controlling the cytosolic Ca(2+) concentration, are linked to Ca(2+)-based signalling. A large number of environmental stimuli can evoke Ca(2+) signals, but the Ca(2+)-induced responses are likely to differ depending on the stimulus applied. Two mechanisms are put forward to explain signal specificity of Ca(2+)-dependent responses. A signal may evoke a specific Ca(2+) signature that is recognized by downstream signalling components. Alternatively, Ca(2+) signals are accompanied by Ca(2+)-independent signalling events that determine the specificity of the response. The existence of such parallel-acting pathways explains why guard cell responses to abscisic acid (ABA) can occur in the absence, as well as in the presence, of Ca(2+) signals. Future research may shed new light on the relation between parallel acting Ca(2+)-dependent and -independent events, and may provide insights in their evolutionary origin.
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Affiliation(s)
- M Rob G Roelfsema
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Julius-von-Sachs-Platz 2, D-97082 Würzburg, Germany.
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38
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Tidow H, Hein KL, Baekgaard L, Palmgren MG, Nissen P. Expression, purification, crystallization and preliminary X-ray analysis of calmodulin in complex with the regulatory domain of the plasma-membrane Ca2+-ATPase ACA8. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:361-3. [PMID: 20208181 DOI: 10.1107/s1744309110003805] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2009] [Accepted: 01/30/2010] [Indexed: 11/10/2022]
Abstract
Plasma-membrane Ca(2+)-ATPases (PMCAs) are calcium pumps that expel Ca(2+) from eukaryotic cells to maintain overall Ca(2+) homoeostasis and to provide local control of intracellular Ca(2+) signalling. They are of major physiological importance, with different isoforms being essential, for example, for presynaptic and postsynaptic Ca(2+) regulation in neurons, feedback signalling in the heart and sperm motility. In the resting state, PMCAs are autoinhibited by binding of their C-terminal (in mammals) or N-terminal (in plants) tail to two major intracellular loops. Activation requires the binding of calcium-bound calmodulin (Ca(2+)-CaM) to this tail and a conformational change that displaces the autoinhibitory tail from the catalytic domain. The complex between calmodulin and the regulatory domain of the plasma-membrane Ca(2+)-ATPase ACA8 from Arabidopsis thaliana has been crystallized. The crystals belonged to space group C2, with unit-cell parameters a = 176.8, b = 70.0, c = 69.8 A, beta = 113.2 degrees. A complete data set was collected to 3.0 A resolution and structure determination is in progress in order to elucidate the mechanism of PMCA activation by calmodulin.
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Affiliation(s)
- Henning Tidow
- Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
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39
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Fusca T, Bonza MC, Luoni L, Meneghelli S, Marrano CA, De Michelis MI. Single point mutations in the small cytoplasmic loop of ACA8, a plasma membrane Ca2+-ATPase of Arabidopsis thaliana, generate partially deregulated pumps. J Biol Chem 2009; 284:30881-8. [PMID: 19740735 DOI: 10.1074/jbc.m109.006148] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
ACA8 is a type 2B Ca(2+)-ATPase having a regulatory N terminus whose auto-inhibitory action can be suppressed by binding of calmodulin (CaM) or of acidic phospholipids. ACA8 N terminus is able to interact with a region of the small cytoplasmic loop connecting transmembrane domains 2 and 3. To determine the role of this interaction in auto-inhibition we analyzed single point mutants produced by mutagenesis of ACA8 Glu(252) to Asn(345) sequence. Mutation to Ala of any of six tested acidic residues (Glu(252), Asp(273), Asp(291), Asp(303), Glu(302), or Asp(332)) renders an enzyme that is less dependent on CaM for activity. These results highlight the relevance in ACA8 auto-inhibition of a negative charge of the surface area of the small cytoplasmic loop. The most deregulated of these mutants is D291A ACA8, which is less activated by controlled proteolysis or by acidic phospholipids; the D291A mutant has an apparent affinity for CaM higher than wild-type ACA8. Moreover, its phenotype is stronger than that of D291N ACA8, suggesting a more direct involvement of this residue in the mechanism of auto-inhibition. Among the other produced mutants (I284A, N286A, P289A, P322A, V344A, and N345A), only P322A ACA8 is less dependent on CaM for activity than the wild type. The results reported in this study provide the first evidence that the small cytoplasmic loop of a type 2B Ca(2+)-ATPase plays a role in the attainment of the auto-inhibited state.
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Affiliation(s)
- Tiziana Fusca
- Dipartimento di Biologia L. Gorini, Università di Milano, Istituto di Biofisica del Consiglio Nazionale delle Ricerche, Sezione di Milano, via G. Celoria 26, Milano 20133, Italy
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40
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Meneghelli S, Fusca T, Luoni L, De Michelis MI. Dual mechanism of activation of plant plasma membrane Ca2+-ATPase by acidic phospholipids: evidence for a phospholipid binding site which overlaps the calmodulin-binding site. Mol Membr Biol 2009; 25:539-46. [PMID: 18988067 DOI: 10.1080/09687680802508747] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The effect of phospholipids on the activity of isoform ACA8 of Arabidopsis thaliana plasma membrane (PM) Ca2+-ATPase was evaluated in membranes isolated from Saccharomyces cerevisiae strain K616 expressing wild type or mutated ACA8 cDNA. Acidic phospholipids stimulated the basal Ca2+-ATPase activity in the following order of efficiency: phosphatidylinositol 4-monophosphate > phosphatidylserine > phosphatidylcholine approximately = phosphatidylethanolamine approximately = 0. Acidic phospholipids increased V(max-Ca2+) and lowered the value of K(0.5-Ca2+) below the value measured in the presence of calmodulin (CaM). In the presence of CaM acidic phospholipids activated ACA8 by further decreasing its K(0.5-Ca2+) value. Phosphatidylinositol 4-monophosphate and, with lower efficiency, phosphatidylserine bound peptides reproducing ACA8 N-terminus (aa 1-116). Single point mutation of three residues (A56, R59 and Y62) within the sequence A56-T63 lowered the apparent affinity of ACA8 for phosphatidylinositol 4-monophosphate by two to three fold, indicating that this region contains a binding site for acidic phospholipids. However, the N-deleted mutant Delta74-ACA8 was also activated by acidic phospholipids, indicating that acidic phospholipids activate ACA8 through a complex mechanism, involving interaction with different sites. The striking similarity between the response to acidic phospholipids of ACA8 and animal plasma membrane Ca2+-ATPase provides new evidence that type 2B Ca2+-ATPases share common regulatory properties independently of structural differences such as the localization of the terminal regulatory region at the N- or C-terminal end of the protein.
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Affiliation(s)
- Silvia Meneghelli
- Dipartimento di Biologia, Universita di Milano, Istituto di Biofisica del CNR, Sezione di Milano, Milano, Italy
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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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Abstract
In numerous plant signal transduction pathways, Ca2+ is a versatile second messenger which controls the activation of many downstream actions in response to various stimuli. There is strong evidence to indicate that information encoded within these stimulus-induced Ca2+ oscillations can provide signalling specificity. Such Ca2+ signals, or 'Ca2+ signatures', are generated in the cytosol, and in noncytosolic locations including the nucleus and chloroplast, through the coordinated action of Ca2+ influx and efflux pathways. An increased understanding of the functions and regulation of these various Ca2+ transporters has improved our appreciation of the role these transporters play in specifically shaping the Ca2+ signatures. Here we review the evidence which indicates that Ca2+ channel, Ca2+-ATPase and Ca2+ exchanger isoforms can indeed modulate specific Ca2+ signatures in response to an individual signal.
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Affiliation(s)
- Martin R McAinsh
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK;Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Jon K Pittman
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK;Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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Boursiac Y, Harper JF. The origin and function of calmodulin regulated Ca2+ pumps in plants. J Bioenerg Biomembr 2008; 39:409-14. [PMID: 18000746 DOI: 10.1007/s10863-007-9104-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
While Ca2+ signaling plays an important role in both plants and animals, the machinery that codes and decodes these signals have evolved to show interesting differences and similarities. For example, typical plant and animal cells both utilize calmodulin (CaM)-regulated Ca2+ pumps at the plasma membrane to help control cytoplasmic Ca2+ levels. However, in flowering plants this family of pumps has evolved with a unique structural arrangement in which the regulatory domain is located at the N-terminal instead of C-terminal end. In addition, some of the plant isoforms have evolved to function at endomembrane locations. For the 14 Ca2+ pumps present in the model plant Arabidopsis, molecular genetic analyses are providing exciting insights into their function in diverse aspects of plant growth and development.
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Affiliation(s)
- Yann Boursiac
- Biochemistry Department MS200, Fleischmann Agriculture Building, University of Nevada, Reno, NV 89557, USA
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44
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Duby G, Boutry M. The plant plasma membrane proton pump ATPase: a highly regulated P-type ATPase with multiple physiological roles. Pflugers Arch 2008; 457:645-55. [PMID: 18228034 DOI: 10.1007/s00424-008-0457-x] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 01/11/2008] [Accepted: 01/14/2008] [Indexed: 12/01/2022]
Abstract
Around 40 P-type ATPases have been identified in Arabidopsis and rice, for which the genomes are known. None seems to exchange sodium and potassium, as does the animal Na(+)/K(+)-ATPase. Instead, plants, together with fungi, possess a proton pumping ATPase (H(+)-ATPase), which couples ATP hydrolysis to proton transport out of the cell, and so establishes an electrochemical gradient across the plasma membrane, which is dissipated by secondary transporters using protons in symport or antiport, as sodium is used in animal cells. Additional functions, such as stomata opening, cell growth, and intracellular pH homeostasis, have been proposed. Crystallographic data and homology modeling suggest that the H(+)-ATPase has a broadly similar structure to the other P-type ATPases but has an extended C-terminal region, which is involved in enzyme regulation. Phosphorylation of the penultimate residue, a Thr, and the subsequent binding of regulatory 14-3-3 proteins result in the formation of a dodecamer (six H(+)-ATPase and six 14-3-3 molecules) and enzyme activation. This type of regulation is unique to the P-type ATPase family. However, the recent identification of additional phosphorylated residues suggests further regulatory features.
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Affiliation(s)
- Geoffrey Duby
- Unité de Biochimie Physiologique, Institut des Sciences de la Vie, Université Catholique de Louvain, 1348 Louvain-La-Neuve, Belgium
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45
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Meneghelli S, Luoni L, De Michelis MI. Heparin Stimulates a Plasma Membrane Ca2+-ATPase of Arabidopsis thaliana. J Biochem 2007; 143:253-9. [DOI: 10.1093/jb/mvm218] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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46
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Rich RL, Myszka DG. Survey of the year 2006 commercial optical biosensor literature. J Mol Recognit 2007; 20:300-66. [DOI: 10.1002/jmr.862] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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47
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Cerana M, Bonza MC, Harris R, Sanders D, De Michelis MI. Abscisic acid stimulates the expression of two isoforms of plasma membrane Ca2+-ATPase in Arabidopsis thaliana seedlings. PLANT BIOLOGY (STUTTGART, GERMANY) 2006; 8:572-8. [PMID: 16821193 DOI: 10.1055/s-2006-924111] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
AT-ACA8 and AT-ACA9 are two plasma membrane (PM) Ca (2+)-ATPases of ARABIDOPSIS THALIANA. In this article the expression of AT-ACA8, AT-ACA9, and of AT-ACA10, a third isoform of Ca (2+)-ATPase closely related to PM Ca (2+)-ATPases, was analysed and the effect of the hormone abscisic acid (ABA) on the expression level of PM Ca (2+)-ATPase specific transcripts was investigated. In adult plants of A. THALIANA, AT-ACA8 and AT-ACA10 are expressed in all organs considered whereas AT-ACA9 is expressed only in flowers. All isoforms of PM Ca (2+)-ATPases can be detected in young seedlings but the amount of AT-ACA9 mRNA is much lower than those of AT-ACA8 and AT-ACA10. ABA markedly and rapidly stimulates the expression of both AT-ACA8 and AT-ACA9 genes in young seedlings but not that of AT-ACA10. ABA also increases the level of AT-ACA8 protein at the PM, suggesting a role for PM Ca (2+)-ATPases in ABA signalling.
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Affiliation(s)
- M Cerana
- Dipartimento di Biologia, Università degli Studi di Milano, Istituto di Biofisica del CNR-Sezione di Milano, Via Celoria 26, 20133 Milano, Italy.
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