1
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Clark G, Tripathy MK, Roux SJ. Growth regulation by apyrases: Insights from altering their expression level in different organisms. PLANT PHYSIOLOGY 2024; 194:1323-1335. [PMID: 37947023 PMCID: PMC10904326 DOI: 10.1093/plphys/kiad590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 11/12/2023]
Abstract
Apyrase (APY) enzymes are nucleoside triphosphate (NTP) diphosphohydrolases that can remove the terminal phosphate from NTPs and nucleoside diphosphates but not from nucleoside monophosphates. They have conserved structures and functions in yeast, plants, and animals. Among the most studied APYs in plants are those in Arabidopsis (Arabidopsis thaliana; AtAPYs) and pea (Pisum sativum; PsAPYs), both of which have been shown to play major roles in regulating plant growth and development. Valuable insights on their functional roles have been gained by transgenically altering their transcript abundance, either by constitutively expressing or suppressing APY genes. This review focuses on recent studies that have provided insights on the mechanisms by which APY activity promotes growth in different organisms. Most of these studies have used transgenic lines that constitutively expressed APY in multiple different plants and in yeast. As APY enzymatic activity can also be changed post-translationally by chemical blockage, this review also briefly covers studies that used inhibitors to suppress APY activity in plants and fungi. It concludes by summarizing some of the main unanswered questions about how APYs regulate plant growth and proposes approaches to answering them.
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Affiliation(s)
- Greg Clark
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, 100 E 24th Street, TX 78712, USA
| | | | - Stanley J Roux
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, 100 E 24th Street, TX 78712, USA
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2
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Oelmüller R, Tseng YH, Gandhi A. Signals and Their Perception for Remodelling, Adjustment and Repair of the Plant Cell Wall. Int J Mol Sci 2023; 24:ijms24087417. [PMID: 37108585 PMCID: PMC10139151 DOI: 10.3390/ijms24087417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/04/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
The integrity of the cell wall is important for plant cells. Mechanical or chemical distortions, tension, pH changes in the apoplast, disturbance of the ion homeostasis, leakage of cell compounds into the apoplastic space or breakdown of cell wall polysaccharides activate cellular responses which often occur via plasma membrane-localized receptors. Breakdown products of the cell wall polysaccharides function as damage-associated molecular patterns and derive from cellulose (cello-oligomers), hemicelluloses (mainly xyloglucans and mixed-linkage glucans as well as glucuronoarabinoglucans in Poaceae) and pectins (oligogalacturonides). In addition, several types of channels participate in mechanosensing and convert physical into chemical signals. To establish a proper response, the cell has to integrate information about apoplastic alterations and disturbance of its wall with cell-internal programs which require modifications in the wall architecture due to growth, differentiation or cell division. We summarize recent progress in pattern recognition receptors for plant-derived oligosaccharides, with a focus on malectin domain-containing receptor kinases and their crosstalk with other perception systems and intracellular signaling events.
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Affiliation(s)
- Ralf Oelmüller
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Department of Plant Physiology, Friedrich-Schiller-University, 07743 Jena, Germany
| | - Yu-Heng Tseng
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Department of Plant Physiology, Friedrich-Schiller-University, 07743 Jena, Germany
| | - Akanksha Gandhi
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Department of Plant Physiology, Friedrich-Schiller-University, 07743 Jena, Germany
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3
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Phase separation of SGS3 drives siRNA body formation and promotes endogenous gene silencing. Cell Rep 2023; 42:111985. [PMID: 36640363 DOI: 10.1016/j.celrep.2022.111985] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/26/2022] [Accepted: 12/23/2022] [Indexed: 01/11/2023] Open
Abstract
The generation of small interfering RNA (siRNA) involves many RNA processing components, including SUPPRESSOR OF GENE SILENCING 3 (SGS3), RNA-DEPENDENT RNA POLYMERASE 6 (RDR6), and DICER-LIKE proteins (DCLs). Nonetheless, how these components are coordinated to produce siRNAs is unclear. Here, we show that SGS3 forms condensates via phase separation in vivo and in vitro. SGS3 interacts with RDR6 and drives it to form siRNA bodies in cytoplasm, which is promoted by SGS3-targeted RNAs. Disrupting SGS3 phase separation abrogates siRNA body assembly and siRNA biogenesis, whereas coexpression of SGS3 and RDR6 induces siRNA body formation in tobacco and yeast cells. Dysfunction in translation and mRNA decay increases the number of siRNA bodies, whereas DCL2/4 mutations enhance their size. Purification of SGS3 condensates identifies numerous RNA-binding proteins and siRNA processing components. Together, our findings reveal that SGS3 phase separation-mediated formation of siRNA bodies is essential for siRNA production and gene silencing.
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4
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Zhang Y, Sun Y, Liu X, Deng J, Yao J, Zhang Y, Deng S, Zhang H, Zhao N, Li J, Zhou X, Zhao R, Chen S. Populus euphratica Apyrases Increase Drought Tolerance by Modulating Stomatal Aperture in Arabidopsis. Int J Mol Sci 2021; 22:ijms22189892. [PMID: 34576057 PMCID: PMC8468604 DOI: 10.3390/ijms22189892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 11/16/2022] Open
Abstract
Stomatal regulation is crucial to reduce water consumption under drought conditions. Extracellular ATP (eATP) serves as a signaling agent in stomatal regulation; however, it is less known whether the eATP mediation of stomatal aperture is linked to apyrases (APYs), the principal enzymes that control the concentration of eATP. To clarify the role of APYs in stomatal control, PeAPY1 and PeAPY2 were isolated from Populus euphratica and transferred into Arabidopsis. Compared with the wild-type Arabidopsis and loss-of-function mutants (Atapy1 and Atapy2), PeAPY1- and PeAPY2-transgenic plants decreased stomatal aperture under mannitol treatment (200 mM, 2 h) and reduced water loss during air exposure (90 min). The role of apyrase in stomatal regulation resulted from its control in eATP-regulated stomatal movements and increased stomatal sensitivity to ABA. The bi-phasic dose-responses to applied nucleotides, i.e., the low ATP (0.3-1.0 mM)-promoted opening and high ATP (>2.0 mM)-promoted closure, were both restricted by P. euphratica apyrases. It is noteworthy that eATP at a low concentration (0.3 mM) counteracted ABA action in the regulation of stomatal aperture, while overexpression of PeAPY1 or PeAPY2 effectively diminished eATP promotion in opening, and consequently enhanced ABA action in closure. We postulate a speculative model of apyrase signaling in eATP- and ABA-regulated stomatal movements under drought.
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Affiliation(s)
- Yanli Zhang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Yuanling Sun
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Xiaojing Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Jiayin Deng
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Jun Yao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Yinan Zhang
- Forestry Institute of New Technology, Chinese Academy of Forestry, Beijing 100091, China;
| | - Shurong Deng
- State Key Laboratory of Tree Genetics and Breeding, The Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China;
| | - Huilong Zhang
- Research Center of Saline and Alkali Land of National Forestry and Grassland Administration, Chinese Academy of Forestry, Beijing 100091, China;
| | - Nan Zhao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Jinke Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Xiaoyang Zhou
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Rui Zhao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
| | - Shaoliang Chen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (Y.Z.); (Y.S.); (X.L.); (J.D.); (J.Y.); (N.Z.); (J.L.); (X.Z.); (R.Z.)
- Correspondence: ; Tel.: +86-10-6233-8129
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5
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Jiang X, Fan L, Li P, Zou X, Zhang Z, Fan S, Gong J, Yuan Y, Shang H. Co-expression network and comparative transcriptome analysis for fiber initiation and elongation reveal genetic differences in two lines from upland cotton CCRI70 RIL population. PeerJ 2021; 9:e11812. [PMID: 34327061 PMCID: PMC8308610 DOI: 10.7717/peerj.11812] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/28/2021] [Indexed: 01/23/2023] Open
Abstract
Upland cotton is the most widely planted for natural fiber around the world, and either lint percentage (LP) or fiber length (FL) is the crucial component tremendously affecting cotton yield and fiber quality, respectively. In this study, two lines MBZ70-053 and MBZ70-236 derived from G. hirsutum CCRI70 recombinant inbred line (RIL) population presenting different phenotypes in LP and FL traits were chosen to conduct RNA sequencing on ovule and fiber samples, aiming at exploring the differences of molecular and genetic mechanisms during cotton fiber initiation and elongation stages. As a result, 249/128, 369/206, 4296/1198 and 3547/2129 up-/down- regulated differentially expressed genes (DGEs) in L2 were obtained at -3, 0, 5 and 10 days post-anthesis (DPA), respectively. Seven gene expression profiles were discriminated using Short Time-series Expression Miner (STEM) analysis; seven modules and hub genes were identified using weighted gene co-expression network analysis. The DEGs were mainly enriched into energetic metabolism and accumulating as well as auxin signaling pathway in initiation and elongation stages, respectively. Meanwhile, 29 hub genes were identified as 14-3-3ω , TBL35, GhACS, PME3, GAMMA-TIP, PUM-7, etc., where the DEGs and hub genes revealed the genetic and molecular mechanisms and differences during cotton fiber development.
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Affiliation(s)
- Xiao Jiang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Liqiang Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Pengtao Li
- School of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, Henan, China
| | - Xianyan Zou
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Zhen Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Senmiao Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Juwu Gong
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Youlu Yuan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Haihong Shang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
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6
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Clark G, Brown KA, Tripathy MK, Roux SJ. Recent Advances Clarifying the Structure and Function of Plant Apyrases (Nucleoside Triphosphate Diphosphohydrolases). Int J Mol Sci 2021; 22:ijms22063283. [PMID: 33807069 PMCID: PMC8004787 DOI: 10.3390/ijms22063283] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/18/2021] [Accepted: 03/20/2021] [Indexed: 01/22/2023] Open
Abstract
Studies implicating an important role for apyrase (NTPDase) enzymes in plant growth and development began appearing in the literature more than three decades ago. After early studies primarily in potato, Arabidopsis and legumes, especially important discoveries that advanced an understanding of the biochemistry, structure and function of these enzymes have been published in the last half-dozen years, revealing that they carry out key functions in diverse other plants. These recent discoveries about plant apyrases include, among others, novel findings on its crystal structures, its biochemistry, its roles in plant stress responses and its induction of major changes in gene expression when its expression is suppressed or enhanced. This review will describe and discuss these recent advances and the major questions about plant apyrases that remain unanswered.
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Affiliation(s)
- Greg Clark
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA; (G.C.); (K.A.B.)
| | - Katherine A. Brown
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA; (G.C.); (K.A.B.)
- Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
| | | | - Stanley J. Roux
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA; (G.C.); (K.A.B.)
- Correspondence: ; Tel.: +1-512-471-4238
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7
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Iwatate RJ, Yoshinari A, Yagi N, Grzybowski M, Ogasawara H, Kamiya M, Komatsu T, Taki M, Yamaguchi S, Frommer WB, Nakamura M. Covalent Self-Labeling of Tagged Proteins with Chemical Fluorescent Dyes in BY-2 Cells and Arabidopsis Seedlings. THE PLANT CELL 2020; 32:3081-3094. [PMID: 32763980 PMCID: PMC7534461 DOI: 10.1105/tpc.20.00439] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/16/2020] [Accepted: 07/31/2020] [Indexed: 05/08/2023]
Abstract
Synthetic chemical fluorescent dyes promise to be useful for many applications in biology. Covalent, targeted labeling, such as with a SNAP-tag, uses synthetic dyes to label specific proteins in vivo for studying processes such as endocytosis or for imaging via super-resolution microscopy. Despite its potential, such chemical tagging has not been used effectively in plants. A major drawback has been the limited knowledge regarding cell wall and membrane permeability of the available synthetic dyes. Of 31 synthetic dyes tested here, 23 were taken up into BY-2 cells, while eight were not. This creates sets of dyes that can serve to measure endocytosis. Three of the dyes that were able to enter the cells, SNAP-tag ligands of diethylaminocoumarin, tetramethylrhodamine, and silicon-rhodamine 647, were used to SNAP-tag α-tubulin. Successful tagging was verified by live cell imaging and visualization of microtubule arrays in interphase and during mitosis in Arabidopsis (Arabidopsis thaliana) seedlings. Fluorescence activation-coupled protein labeling with DRBG-488 was used to observe PIN-FORMED2 (PIN2) endocytosis and delivery to the vacuole as well as preferential delivery of newly synthesized PIN2 to the actively forming cell plate during mitosis. Together, the data demonstrate that specific self-labeling of proteins can be used effectively in plants to study a wide variety of cellular and biological processes.
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Affiliation(s)
- Ryu J Iwatate
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
- School of Medicine, Nagoya University, Showa, Nagoya 466-8550, Japan
| | - Akira Yoshinari
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Noriyoshi Yagi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Marek Grzybowski
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Hiroaki Ogasawara
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Mako Kamiya
- Graduate School of Medicine, University of Tokyo, Tokyo 113-0033, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Toru Komatsu
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan
| | - Masayasu Taki
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan
| | - Shigehiro Yamaguchi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan
| | - Wolf B Frommer
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Institute for Molecular Physiology, Heinrich-Heine-University Düsseldorf, Düsseldorf 40225, Germany
| | - Masayoshi Nakamura
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
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8
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Pietrowska-Borek M, Dobrogojski J, Sobieszczuk-Nowicka E, Borek S. New Insight into Plant Signaling: Extracellular ATP and Uncommon Nucleotides. Cells 2020; 9:E345. [PMID: 32024306 PMCID: PMC7072326 DOI: 10.3390/cells9020345] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 01/27/2020] [Accepted: 01/30/2020] [Indexed: 12/15/2022] Open
Abstract
New players in plant signaling are described in detail in this review: extracellular ATP (eATP) and uncommon nucleotides such as dinucleoside polyphosphates (NpnN's), adenosine 5'-phosphoramidate (NH2-pA), and extracellular NAD+ and NADP+ (eNAD(P)+). Recent molecular, physiological, and biochemical evidence implicating concurrently the signaling role of eATP, NpnN's, and NH2-pA in plant biology and the mechanistic events in which they are involved are discussed. Numerous studies have shown that they are often universal signaling messengers, which trigger a signaling cascade in similar reactions and processes among different kingdoms. We also present here, not described elsewhere, a working model of the NpnN' and NH2-pA signaling network in a plant cell where these nucleotides trigger induction of the phenylpropanoid and the isochorismic acid pathways yielding metabolites protecting the plant against various types of stresses. Through these signals, the plant responds to environmental stimuli by intensifying the production of various compounds, such as anthocyanins, lignin, stilbenes, and salicylic acid. Still, more research needs to be performed to identify signaling networks that involve uncommon nucleotides, followed by omic experiments to define network elements and processes that are controlled by these signals.
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Affiliation(s)
- Małgorzata Pietrowska-Borek
- Department of Biochemistry and Biotechnology, Faculty of Agronomy and Bioengineering, Poznań University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland;
| | - Jędrzej Dobrogojski
- Department of Biochemistry and Biotechnology, Faculty of Agronomy and Bioengineering, Poznań University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland;
| | - Ewa Sobieszczuk-Nowicka
- Department of Plant Physiology, Faculty of Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland; (E.S.-N.); (S.B.)
| | - Sławomir Borek
- Department of Plant Physiology, Faculty of Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland; (E.S.-N.); (S.B.)
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9
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Veerappa R, Slocum RD, Siegenthaler A, Wang J, Clark G, Roux SJ. Ectopic expression of a pea apyrase enhances root system architecture and drought survival in Arabidopsis and soybean. PLANT, CELL & ENVIRONMENT 2019; 42:337-353. [PMID: 30132918 DOI: 10.1111/pce.13425] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 08/13/2018] [Indexed: 05/27/2023]
Abstract
Ectoapyrases (ecto-NTPDases) function to decrease levels of extracellular ATP and ADP in animals and plants. Prior studies showed that ectopic expression of a pea ectoapyrase, psNTP9, enhanced growth in Arabidopsis seedlings and that the overexpression of the two Arabidopsis apyrases most closely related to psNTP9 enhanced auxin transport and growth in Arabidopsis. These results predicted that ectopic expression of psNTP9 could promote a more extensive root system architecture (RSA) in Arabidopsis. We confirmed that transgenic Arabidopsis seedlings had longer primary roots, more lateral roots, and more and longer root hairs than wild-type plants. Because RSA influences water uptake, we tested whether the transgenic plants could tolerate osmotic stress and water deprivation better than wild-type plants, and we confirmed these properties. Transcriptomic analyses revealed gene expression changes in the transgenic plants that helped account for their enhanced RSA and improved drought tolerance. The effects of psNTP9 were not restricted to Arabidopsis, because its expression in soybeans improved the RSA, growth, and seed yield of this crop and supported higher survival in response to drought. Our results indicate that in both Arabidopsis and soybeans, the constitutive expression of psNTP9 results in a more extensive RSA and improved survival in drought stress conditions.
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Affiliation(s)
| | - Robert D Slocum
- Department of Biological Sciences, Goucher College, Towson, Maryland
| | | | - Jing Wang
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Greg Clark
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Stanley J Roux
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
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10
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Zhang Y, Nikolovski N, Sorieul M, Vellosillo T, McFarlane HE, Dupree R, Kesten C, Schneider R, Driemeier C, Lathe R, Lampugnani E, Yu X, Ivakov A, Doblin MS, Mortimer JC, Brown SP, Persson S, Dupree P. Golgi-localized STELLO proteins regulate the assembly and trafficking of cellulose synthase complexes in Arabidopsis. Nat Commun 2016; 7:11656. [PMID: 27277162 PMCID: PMC4906169 DOI: 10.1038/ncomms11656] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 04/15/2016] [Indexed: 01/24/2023] Open
Abstract
As the most abundant biopolymer on Earth, cellulose is a key structural component of the plant cell wall. Cellulose is produced at the plasma membrane by cellulose synthase (CesA) complexes (CSCs), which are assembled in the endomembrane system and trafficked to the plasma membrane. While several proteins that affect CesA activity have been identified, components that regulate CSC assembly and trafficking remain unknown. Here we show that STELLO1 and 2 are Golgi-localized proteins that can interact with CesAs and control cellulose quantity. In the absence of STELLO function, the spatial distribution within the Golgi, secretion and activity of the CSCs are impaired indicating a central role of the STELLO proteins in CSC assembly. Point mutations in the predicted catalytic domains of the STELLO proteins indicate that they are glycosyltransferases facing the Golgi lumen. Hence, we have uncovered proteins that regulate CSC assembly in the plant Golgi apparatus.
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Affiliation(s)
- Yi Zhang
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Nino Nikolovski
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Mathias Sorieul
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Tamara Vellosillo
- Energy Biosciences Institute, and Plant and Microbial Biology Department, University of California, Berkeley, California 94720, USA
| | - Heather E McFarlane
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ray Dupree
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Christopher Kesten
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - René Schneider
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Carlos Driemeier
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo CEP 13083-970, Brazil
| | - Rahul Lathe
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Edwin Lampugnani
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Xiaolan Yu
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Alexander Ivakov
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Monika S Doblin
- School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Jenny C Mortimer
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Steven P Brown
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Staffan Persson
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany.,School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia.,ARC Centre of Excellence in Plant Cell Walls, School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
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Yang X, Wang B, Farris B, Clark G, Roux SJ. Modulation of Root Skewing in Arabidopsis by Apyrases and Extracellular ATP. PLANT & CELL PHYSIOLOGY 2015; 56:2197-206. [PMID: 26412783 DOI: 10.1093/pcp/pcv134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 09/16/2015] [Indexed: 05/04/2023]
Abstract
When plant primary roots grow along a tilted surface that is impenetrable, they can undergo a slanted deviation from the direction of gravity called skewing. Skewing is induced by touch stimuli which the roots experience as they grow along the surface. Touch stimuli also induce the release of extracellular ATP (eATP) into the plant's extracellular matrix, and two apyrases (NTPDases) in Arabidopsis, APY1 and APY2, can help regulate the concentration of eATP. The primary roots of seedlings overexpressing APY1 show less skewing than wild-type plants. Plants suppressed in their expression of APY1 show more skewing than wild-type plants. Correspondingly, chemical inhibition of apyrase activity increased skewing in mutants and wild-type roots. Exogenous application of ATP or ATPγS also increased skewing in wild-type roots, which could be blocked by co-incubation with a purinergic receptor antagonist. These results suggest a model in which gradients of eATP set up by differential touch stimuli along roots help direct skewing in roots growing along an impenetrable surface.
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Affiliation(s)
- Xingyan Yang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400030, China
| | - Bochu Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400030, China
| | - Ben Farris
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Greg Clark
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Stanley J Roux
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
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12
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Biochemical characterization of Arabidopsis APYRASE family reveals their roles in regulating endomembrane NDP/NMP homoeostasis. Biochem J 2015; 472:43-54. [PMID: 26338998 DOI: 10.1042/bj20150235] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 09/03/2015] [Indexed: 12/27/2022]
Abstract
Plant apyrases are nucleoside triphosphate (NTP) diphosphohydrolases (NTPDases) and have been implicated in an array of functions within the plant including the regulation of extracellular ATP. Arabidopsis encodes a family of seven membrane bound apyrases (AtAPY1-7) that comprise three distinct clades, all of which contain the five conserved apyrase domains. With the exception of AtAPY1 and AtAPY2, the biochemical and the sub-cellular characterization of the other members are currently unavailable. In this research, we have shown all seven Arabidopsis apyrases localize to internal membranes comprising the cis-Golgi, endoplasmic reticulum (ER) and endosome, indicating an endo-apyrase classification for the entire family. In addition, all members, with the exception of AtAPY7, can function as endo-apyrases by complementing a yeast double mutant (Δynd1Δgda1) which lacks apyrase activity. Interestingly, complementation of the mutant yeast using well characterized human apyrases could only be accomplished by using a functional ER endo-apyrase (NTPDase6), but not the ecto-apyrase (NTPDase1). Furthermore, the substrate specificity analysis for the Arabidopsis apyrases AtAPY1-6 indicated that each member has a distinct set of preferred substrates covering various NDPs (nucleoside diphosphates) and NTPs. Combining the biochemical analysis and sub-cellular localization of the Arabidopsis apyrases family, the data suggest their possible roles in regulating endomembrane NDP/NMP (nucleoside monophosphate) homoeostasis.
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13
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Deng S, Sun J, Zhao R, Ding M, Zhang Y, Sun Y, Wang W, Tan Y, Liu D, Ma X, Hou P, Wang M, Lu C, Shen X, Chen S. Populus euphratica APYRASE2 Enhances Cold Tolerance by Modulating Vesicular Trafficking and Extracellular ATP in Arabidopsis Plants. PLANT PHYSIOLOGY 2015; 169:530-548. [PMID: 26224801 PMCID: PMC4577398 DOI: 10.1104/pp.15.00581] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 07/28/2015] [Indexed: 05/20/2023]
Abstract
Apyrase and extracellular ATP play crucial roles in mediating plant growth and defense responses. In the cold-tolerant poplar, Populus euphratica, low temperatures up-regulate APYRASE2 (PeAPY2) expression in callus cells. We investigated the biochemical characteristics of PeAPY2 and its role in cold tolerance. We found that PeAPY2 predominantly localized to the plasma membrane, but punctate signals also appeared in the endoplasmic reticulum and Golgi apparatus. PeAPY2 exhibited broad substrate specificity, but it most efficiently hydrolyzed purine nucleotides, particularly ATP. PeAPY2 preferred Mg(2+) as a cofactor, and it was insensitive to various, specific ATPase inhibitors. When PeAPY2 was ectopically expressed in Arabidopsis (Arabidopsis thaliana), cold tolerance was enhanced, based on root growth measurements and survival rates. Moreover, under cold stress, PeAPY2-transgenic plants maintained plasma membrane integrity and showed reduced cold-elicited electrolyte leakage compared with wild-type plants. These responses probably resulted from efficient plasma membrane repair via vesicular trafficking. Indeed, transgenic plants showed accelerated endocytosis and exocytosis during cold stress and recovery. We found that low doses of extracellular ATP accelerated vesicular trafficking, but high extracellular ATP inhibited trafficking and reduced cell viability. Cold stress caused significant increases in root medium extracellular ATP. However, under these conditions, PeAPY2-transgenic lines showed greater control of extracellular ATP levels than wild-type plants. We conclude that Arabidopsis plants that overexpressed PeAPY2 could increase membrane repair by accelerating vesicular trafficking and hydrolyzing extracellular ATP to avoid excessive, cold-elicited ATP accumulation in the root medium and, thus, reduced ATP-induced inhibition of vesicular trafficking.
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Affiliation(s)
- Shurong Deng
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Jian Sun
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Rui Zhao
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Mingquan Ding
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Yinan Zhang
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Yuanling Sun
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Wei Wang
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Yeqing Tan
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Dandan Liu
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Xujun Ma
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Peichen Hou
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Meijuan Wang
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Cunfu Lu
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Xin Shen
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
| | - Shaoliang Chen
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (S.D., R.Z., Y.Z., Y.S., W.W., Y.T., D.L., X.M., M.W., C.L., X.S., S.C.);College of Life Science, Jiangsu Normal University, Xuzhou 221116, People's Republic of China (J.S.);College of Agricultural and Food Science, Zhejiang Agricultural and Forestry University, Hangzhou 311300, People's Republic of China (M.D.); andNational Engineering Research Center for Information Technology in Agriculture, Beijing 100097, People's Republic of China (P.H.)
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Massalski C, Bloch J, Zebisch M, Steinebrunner I. The biochemical properties of the Arabidopsis ecto-nucleoside triphosphate diphosphohydrolase AtAPY1 contradict a direct role in purinergic signaling. PLoS One 2015; 10:e0115832. [PMID: 25822168 PMCID: PMC4379058 DOI: 10.1371/journal.pone.0115832] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 12/02/2014] [Indexed: 11/18/2022] Open
Abstract
The Arabidopsis E-NTPDase (ecto-nucleoside triphosphate diphosphohydrolase) AtAPY1 was previously shown to be involved in growth and development, pollen germination and stress responses. It was proposed to perform these functions through regulation of extracellular ATP signals. However, a GFP-tagged version was localized exclusively in the Golgi and did not hydrolyze ATP. In this study, AtAPY1 without the bulky GFP-tag was biochemically characterized with regard to its suggested role in purinergic signaling. Both the full-length protein and a soluble form without the transmembrane domain near the N-terminus were produced in HEK293 cells. Of the twelve nucleotide substrates tested, only three--GDP, IDP and UDP--were hydrolyzed, confirming that ATP was not a substrate of AtAPY1. In addition, the effects of pH, divalent metal ions, known E-NTPDase inhibitors and calmodulin on AtAPY1 activity were analyzed. AtAPY1-GFP extracted from transgenic Arabidopsis seedlings was included in the analyses. All three AtAPY1 versions exhibited very similar biochemical properties. Activity was detectable in a broad pH range, and Ca(2+), Mg(2+) and Mn(2+) were the three most efficient cofactors. Of the inhibitors tested, vanadate was the most potent one. Surprisingly, sulfonamide-based inhibitors shown to inhibit other E-NTPDases and presumed to inhibit AtAPY1 as well were not effective. Calmodulin stimulated the activity of the GFP-tagless membranous and soluble AtAPY1 forms about five-fold, but did not alter their substrate specificities. The apparent Km values obtained with AtAPY1-GFP indicate that AtAPY1 is primarily a GDPase. A putative three-dimensional structural model of the ecto-domain is presented, explaining the potent inhibitory potential of vanadate and predicting the binding mode of GDP. The found substrate specificity classifies AtAPY1 as a nucleoside diphosphatase typical of N-terminally anchored Golgi E-NTPDases and negates a direct function in purinergic signaling.
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Affiliation(s)
- Carolin Massalski
- Department of Biology, Technische Universität Dresden, Dresden, Germany
| | - Jeannine Bloch
- Department of Biology, Technische Universität Dresden, Dresden, Germany
| | - Matthias Zebisch
- Division of Structural Biology, University of Oxford, Oxford, United Kingdom
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15
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Poulsen CP, Dilokpimol A, Geshi N. Arabinogalactan biosynthesis: Implication of AtGALT29A enzyme activity regulated by phosphorylation and co-localized enzymes for nucleotide sugar metabolism in the compartments outside of the Golgi apparatus. PLANT SIGNALING & BEHAVIOR 2015; 10:e984524. [PMID: 25723364 PMCID: PMC4622509 DOI: 10.4161/15592324.2014.984524] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/29/2014] [Accepted: 09/29/2014] [Indexed: 05/27/2023]
Abstract
Arabinogalactan proteins are abundant cell surface proteoglycans in plants and are implicated to act as developmental markers during plant growth. We previously reported that AtGALT31A, AtGALT29A, and AtGLCAT14A-C, which are involved in the biosynthesis of arabinogalactan proteins, localize not only to the Golgi cisternae but also to smaller compartments, which may be a part of the unconventional protein secretory pathway in plants. In Poulsen et al., (1) we have demonstrated increased targeting of AtGALT29A to small compartments when Y144 is substituted with another amino acid, and we implicated a role for Y144 in the subcellular targeting of AtGALT29A. In this paper, we are presenting another aspect of Y144 substitution in AtGALT29A; namely, Y144A construct demonstrated a 2.5-fold increase while Y144E construct demonstrated a 2-fold decrease in the galactosyltransferase activity of AtGALT29A. Therefore, the electrostatic status of Y144, which is regulated by an unknown kinase/phosphatase system, may regulate AtGALT29A enzyme activity. Moreover, we have identified additional proteins, apyrase 3 (APY3; At1g14240) and UDP-glucuronate epimerases 1 and 6 (GAE1, At4g30440; GAE6, At3g23820), from Arabidopsis thaliana that co-localize with AtGALT31A in the small compartments when expressed transiently in Nicotiana benthamiana. These proteins may play roles in nucleotide sugar metabolism in the small compartments together with arabinogalactan glycosyltransferases.
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Affiliation(s)
- Christian Peter Poulsen
- Department of Plant and Environmental Sciences; University of Copenhagen; Frederiksberg C, Denmark
| | - Adiphol Dilokpimol
- Department of Plant and Environmental Sciences; University of Copenhagen; Frederiksberg C, Denmark
- Present address: Fungal Physiology; CBS-KNAW Fungal Biodiversity Center; Utrecht CT, The Netherlands
| | - Naomi Geshi
- Department of Plant and Environmental Sciences; University of Copenhagen; Frederiksberg C, Denmark
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16
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Clark GB, Morgan RO, Fernandez MP, Salmi ML, Roux SJ. Breakthroughs spotlighting roles for extracellular nucleotides and apyrases in stress responses and growth and development. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 225:107-116. [PMID: 25017166 DOI: 10.1016/j.plantsci.2014.06.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 05/31/2014] [Accepted: 06/02/2014] [Indexed: 06/03/2023]
Abstract
Animal and plant cells release nucleotides into their extracellular matrix when touched, wounded, and when their plasma membranes are stretched during delivery of secretory vesicles and growth. These released nucleotides then function as signaling agents that induce rapid increases in the concentration of cytosolic calcium, nitric oxide and superoxide. These, in turn, are transduced into downstream physiological changes. These changes in plants include changes in the growth of diverse tissues, in gravitropism, and in the opening and closing of stomates. The concentration of extracellular nucleotides is controlled by various phosphatases, prominent among which are apyrases EC 3.6.1.5 (nucleoside triphosphate diphosphohydrolases, NTPDases). This review provides phylogenetic and pHMM analyses of plant apyrases as well as analysis of predicted post-translational modifications for Arabidopsis apyrases. This review also summarizes and discusses recent advances in research on the roles of apyrases and extracellular nucleotides in controlling plant growth and development. These include new findings that document how apyrases and extracellular nucleotides control auxin transport, modulate stomatal aperture, and mediate biotic and abiotic stress responses, and on how apyrase suppression leads to growth inhibition.
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Affiliation(s)
- Greg B Clark
- Department of Molecular Biosciences, University of Texas, Austin, TX 78713, USA
| | - Reginald O Morgan
- Department of Biochemistry and Molecular Biology, Faculty of Medicine and University Institute of Biotechnology of Asturias, University of Oviedo, E-33006 Oviedo, Spain
| | - Maria-Pilar Fernandez
- Department of Biochemistry and Molecular Biology, Faculty of Medicine and University Institute of Biotechnology of Asturias, University of Oviedo, E-33006 Oviedo, Spain
| | - Mari L Salmi
- Department of Molecular Biosciences, University of Texas, Austin, TX 78713, USA
| | - Stanley J Roux
- Department of Molecular Biosciences, University of Texas, Austin, TX 78713, USA.
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Paul P, Simm S, Mirus O, Scharf KD, Fragkostefanakis S, Schleiff E. The complexity of vesicle transport factors in plants examined by orthology search. PLoS One 2014; 9:e97745. [PMID: 24844592 PMCID: PMC4028247 DOI: 10.1371/journal.pone.0097745] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 04/24/2014] [Indexed: 11/18/2022] Open
Abstract
Vesicle transport is a central process to ensure protein and lipid distribution in eukaryotic cells. The current knowledge on the molecular components and mechanisms of this process is majorly based on studies in Saccharomyces cerevisiae and Arabidopsis thaliana, which revealed 240 different proteinaceous factors either experimentally proven or predicted to be involved in vesicle transport. In here, we performed an orthologue search using two different algorithms to identify the components of the secretory pathway in yeast and 14 plant genomes by using the 'core-set' of 240 factors as bait. We identified 4021 orthologues and (co-)orthologues in the discussed plant species accounting for components of COP-II, COP-I, Clathrin Coated Vesicles, Retromers and ESCRTs, Rab GTPases, Tethering factors and SNAREs. In plants, we observed a significantly higher number of (co-)orthologues than yeast, while only 8 tethering factors from yeast seem to be absent in the analyzed plant genomes. To link the identified (co-)orthologues to vesicle transport, the domain architecture of the proteins from yeast, genetic model plant A. thaliana and agriculturally relevant crop Solanum lycopersicum has been inspected. For the orthologous groups containing (co-)orthologues from yeast, A. thaliana and S. lycopersicum, we observed the same domain architecture for 79% (416/527) of the (co-)orthologues, which documents a very high conservation of this process. Further, publically available tissue-specific expression profiles for a subset of (co-)orthologues found in A. thaliana and S. lycopersicum suggest that some (co-)orthologues are involved in tissue-specific functions. Inspection of localization of the (co-)orthologues based on available proteome data or localization predictions lead to the assignment of plastid- as well as mitochondrial localized (co-)orthologues of vesicle transport factors and the relevance of this is discussed.
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Affiliation(s)
- Puneet Paul
- Department of Biosciences Molecular Cell Biology of Plants
| | - Stefan Simm
- Department of Biosciences Molecular Cell Biology of Plants
| | - Oliver Mirus
- Department of Biosciences Molecular Cell Biology of Plants
| | | | | | - Enrico Schleiff
- Department of Biosciences Molecular Cell Biology of Plants
- Cluster of Excellence Frankfurt
- Center of Membrane Proteomics; Goethe University Frankfurt, Frankfurt/Main, Germany
- * E-mail:
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18
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Lim MH, Wu J, Yao J, Gallardo IF, Dugger JW, Webb LJ, Huang J, Salmi ML, Song J, Clark G, Roux SJ. Apyrase suppression raises extracellular ATP levels and induces gene expression and cell wall changes characteristic of stress responses. PLANT PHYSIOLOGY 2014; 164:2054-67. [PMID: 24550243 PMCID: PMC3982762 DOI: 10.1104/pp.113.233429] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 02/13/2014] [Indexed: 05/20/2023]
Abstract
Plant cells release ATP into their extracellular matrix as they grow, and extracellular ATP (eATP) can modulate the rate of cell growth in diverse tissues. Two closely related apyrases (APYs) in Arabidopsis (Arabidopsis thaliana), APY1 and APY2, function, in part, to control the concentration of eATP. The expression of APY1/APY2 can be inhibited by RNA interference, and this suppression leads to an increase in the concentration of eATP in the extracellular medium and severely reduces growth. To clarify how the suppression of APY1 and APY2 is linked to growth inhibition, the gene expression changes that occur in seedlings when apyrase expression is suppressed were assayed by microarray and quantitative real-time-PCR analyses. The most significant gene expression changes induced by APY suppression were in genes involved in biotic stress responses, which include those genes regulating wall composition and extensibility. These expression changes predicted specific chemical changes in the walls of mutant seedlings, and two of these changes, wall lignification and decreased methyl ester bonds, were verified by direct analyses. Taken together, the results are consistent with the hypothesis that APY1, APY2, and eATP play important roles in the signaling steps that link biotic stresses to plant defense responses and growth changes.
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19
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Langhans M, Meckel T. Single-molecule detection and tracking in plants. PROTOPLASMA 2014; 251:277-91. [PMID: 24385216 DOI: 10.1007/s00709-013-0601-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 12/12/2013] [Indexed: 05/07/2023]
Abstract
Combining optical properties with a limited choice of fluorophores turns single-molecule imaging in plants into a challenging task. This explains why the technique, despite its success in the field of animal cell biology, is far from being routinely applied in plant cell research. The same challenges, however, also apply to the application of single-molecule microscopy to any intact tissue or multicellular 3D cell culture. As recent and upcoming progress in fluorescence microscopy will permit single-molecule detection in the context of multicellular systems, plant tissue imaging will experience a huge benefit from this progress. In this review, we address every step of a single-molecule experiment, highlight the critical aspects of each and elaborate on optimizations and developments required for improvements. We relate each step to recent achievements, which have so far been conducted exclusively on the root epidermis of Arabidopsis thaliana seedlings with inclined illumination and show examples of single-molecule measurements using different cells or illumination schemes.
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Affiliation(s)
- Markus Langhans
- Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 3-5, 64287, Darmstadt, Germany
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Nucleotides and Nucleosides: Transport, Metabolism, and Signaling Function of Extracellular ATP. PROGRESS IN BOTANY 2014. [DOI: 10.1007/978-3-642-38797-5_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Salmi ML, Clark G, Roux SJ. Current status and proposed roles for nitric oxide as a key mediator of the effects of extracellular nucleotides on plant growth. FRONTIERS IN PLANT SCIENCE 2013; 4:427. [PMID: 24298275 PMCID: PMC3829461 DOI: 10.3389/fpls.2013.00427] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 10/09/2013] [Indexed: 05/20/2023]
Abstract
Recent data indicate that nucleotides are released into the extracellular matrix during plant cell growth, and that these extracellular nucleotides induce signaling changes that can, in a dose-dependent manner, increase or decrease the cell growth. After activation of a presumed receptor, the earliest signaling change induced by extracellular nucleotides is an increase in the concentration of cytosolic Ca(2+), but rapidly following this change is an increase in the cellular level of nitric oxide (NO). In Arabidopsis, mutants deficient in nitrate reductase activity (nia1nia2) have drastically reduced nitric oxide production and cannot transduce the effects of applied nucleotides into growth changes. Both increased levels of extracellular nucleotides and increased NO production inhibit auxin transport and inhibit growth, and these effects are potentially due to disruption of the localization and/or function of auxin transport facilitators. However, because NO- and auxin-induced signaling pathways can intersect at multiple points, there may be diverse ways by which the induction of NO by extracellular ATP could modulate auxin signaling and thus influence growth. This review will discuss these optional mechanisms and suggest possible regulatory routes based on current experimental data and predictive computational analyses.
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Affiliation(s)
| | | | - Stanley J. Roux
- *Correspondence: Stanley J. Roux, Department of Molecular Biosciences, The University of Texas at Austin, 1 University Station A6700, 205 West 24th Street, BIO 16, Austin, TX 78712-0183, USA e-mail:
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Yang J, Wu J, Romanovicz D, Clark G, Roux SJ. Co-regulation of exine wall patterning, pollen fertility and anther dehiscence by Arabidopsis apyrases 6 and 7. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 69:62-73. [PMID: 23728389 DOI: 10.1016/j.plaphy.2013.04.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 04/29/2013] [Indexed: 05/02/2023]
Abstract
An NCBI nucleotide blast keyed to apyrase (ATP-diphosphohydrolases, EC 3.6.1.5) conserved regions revealed five apyrases, AtAPYs (3-7), in addition to the previously identified AtAPY1 and 2. Here we report the functional analyses of two of the newly defined apyrases, AtAPY6 and AtAPY7. We analyzed tissue specificity of AtAPY6 and 7 expression by qRT-PCR and promoter:GUS fusion assays. We characterized the phenotypes of single and double knockout mutants for AtAPY6 and 7 in anther and pollen by light microscopy and electron microscopy. The transcripts of both AtAPY6 and 7 are expressed in mature pollen grains. Single knockout mutants of AtAPY6 and 7 displayed a minor change in pollen exine pattern under scanning electron microscopy without obvious change in fertility. Double knockout mutants of AtAPY6 and 7 (apy6apy7) displayed severe defects in pollen exine pattern, deformed pollen shape and reduced male fertility. An analysis of pollen from heterozygous apy6apy7 plants suggests that the defects in pollen exine wall are determined by the diploid genome. Our findings demonstrate that AtAPY6 and AtAPY7 are enzymes that play an important role in exine development of pollen grains, possibly through regulating the production of key polysaccharides needed for proper assembly of the exine layer.
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Affiliation(s)
- Jian Yang
- Section of Molecular Cell and Developmental Biology, University of Texas at Austin, 1 University Station A6700, Austin TX 78712, USA
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Zebisch M, Krauss M, Schäfer P, Lauble P, Sträter N. Crystallographic snapshots along the reaction pathway of nucleoside triphosphate diphosphohydrolases. Structure 2013; 21:1460-75. [PMID: 23830739 DOI: 10.1016/j.str.2013.05.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/25/2013] [Accepted: 05/07/2013] [Indexed: 12/13/2022]
Abstract
In vertebrates, membrane-bound ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) on the cell surface are responsible for signal conversion and termination in purinergic signaling by extracellular nucleotides. Here we present apo and complex structures of the rat NTPDase2 extracellular domain and Legionella pneumophila NTPDase1, including a high-resolution structure with a transition-state analog. Comparison of ATP and ADP binding modes shows how NTPDases engage the same catalytic site for hydrolysis of nucleoside triphosphates and diphosphates. We find that this dual specificity is achieved at the expense of base specificity. Structural and mutational studies indicate that a conserved active-site water is replaced by the phosphate product immediately after phosphoryl transfer. Partial base specificity for purines in LpNTPDase1 is based on a different intersubunit base binding site for pyrimidine bases. A comparison of the bacterial enzyme in six independent crystal forms shows that NTPDases can undergo a domain closure motion of at least 17°.
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Affiliation(s)
- Matthias Zebisch
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, University of Leipzig, 04103 Leipzig, Germany
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Shaw SL, Ehrhardt DW. Smaller, faster, brighter: advances in optical imaging of living plant cells. ANNUAL REVIEW OF PLANT BIOLOGY 2013; 64:351-75. [PMID: 23506334 DOI: 10.1146/annurev-arplant-042110-103843] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The advent of fluorescent proteins and access to modern imaging technologies have dramatically accelerated the pace of discovery in plant cell biology. Remarkable new insights into such diverse areas as plant pathogenesis, cytoskeletal dynamics, sugar transport, cell wall synthesis, secretory control, and hormone signaling have come from careful examination of living cells using advanced optical probes. New technologies, both commercially available and on the horizon, promise a continued march toward more quantitative methods for imaging and for extending the optical exploration of biological structure and activity to molecular scales. In this review, we lay out fundamental issues in imaging plant specimens and look ahead to several technological innovations in molecular tools, instrumentation, imaging methods, and specimen handling that show promise for shaping the coming era of plant cell biology.
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Affiliation(s)
- Sidney L Shaw
- Department of Biology, Indiana University, Bloomington, IN 47405, USA.
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Liu X, Wu J, Clark G, Lundy S, Lim M, Arnold D, Chan J, Tang W, Muday GK, Gardner G, Roux SJ. Role for apyrases in polar auxin transport in Arabidopsis. PLANT PHYSIOLOGY 2012; 160:1985-95. [PMID: 23071251 PMCID: PMC3510125 DOI: 10.1104/pp.112.202887] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 10/10/2012] [Indexed: 05/20/2023]
Abstract
Recent evidence indicates that extracellular nucleotides regulate plant growth. Exogenous ATP has been shown to block auxin transport and gravitropic growth in primary roots of Arabidopsis (Arabidopsis thaliana). Cells limit the concentration of extracellular ATP in part through the activity of ectoapyrases (ectonucleoside triphosphate diphosphohydrolases), and two nearly identical Arabidopsis apyrases, APY1 and APY2, appear to share this function. These findings, plus the fact that suppression of APY1 and APY2 blocks growth in Arabidopsis, suggested that the expression of these apyrases could influence auxin transport. This report tests that hypothesis. The polar movement of [(3)H]indole-3-acetic acid in both hypocotyl sections and primary roots of Arabidopsis seedlings was measured. In both tissues, polar auxin transport was significantly reduced in apy2 null mutants when they were induced by estradiol to suppress the expression of APY1 by RNA interference. In the hypocotyl assays, the basal halves of APY-suppressed hypocotyls contained considerably lower free indole-3-acetic acid levels when compared with wild-type plants, and disrupted auxin transport in the APY-suppressed roots was reflected by their significant morphological abnormalities. When a green fluorescent protein fluorescence signal encoded by a DR5:green fluorescent protein construct was measured in primary roots whose apyrase expression was suppressed either genetically or chemically, the roots showed no signal asymmetry following gravistimulation, and both their growth and gravitropic curvature were inhibited. Chemicals that suppress apyrase activity also inhibit gravitropic curvature and, to a lesser extent, growth. Taken together, these results indicate that a critical step connecting apyrase suppression to growth suppression is the inhibition of polar auxin transport.
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Chiu TY, Christiansen K, Moreno I, Lao J, Loqué D, Orellana A, Heazlewood JL, Clark G, Roux SJ. AtAPY1 and AtAPY2 function as Golgi-localized nucleoside diphosphatases in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2012; 53:1913-25. [PMID: 23034877 DOI: 10.1093/pcp/pcs131] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Nucleoside triphosphate diphosphohydrolases (NTPDases; apyrases) (EC 3.6.1.5) hydrolyze di- and triphosphate nucleotides, but not monophosphate nucleotides. They are categorized as E-type ATPases, have a broad divalent cation (Mg(2+), Ca(2+)) requirement for activation and are insensitive to inhibitors of F-type, P-type and V-type ATPases. Among the seven NTPDases identified in Arabidopsis, only APYRASE 1 (AtAPY1) and APYRASE 2 (AtAPY2) have been previously characterized. In this work, either AtAPY1 or AtAPY2 tagged with C-terminal green fluorescent protein (GFP) driven by their respective native promoter can rescue the apy1 apy2 double knockout (apy1 apy2 dKO) successfully, and confocal microscopy reveals that these two Arabidopsis apyrases reside in the Golgi apparatus. In Saccharomyces cerevisiae, both AtAPY1 and AtAPY2 can complement the Golgi-localized GDA1 mutant, rescuing its aberrant protein glycosylation phenotype. In Arabidopsis, microsomes of the wild type show higher substrate preferences toward UDP compared with other NDP substrates. Loss-of-function Arabidopsis AtAPY1 mutants exhibit reduced microsomal UDPase activity, and this activity is even more significantly reduced in the loss-of-function AtAPY2 mutant and in the AtAPY1/AtAPY2 RNA interference (RNAi) technology repressor lines. Microsomes from wild-type plants also have detectable GDPase activity, which is significantly reduced in apy2 but not apy1 mutants. The GFP-tagged AtAPY1 or AtAPY2 constructs in the apy1 apy2 dKO plants can restore microsomal UDP/GDPase activity, confirming that they both also have functional competency. The cell walls of apy1, apy2 and the RNAi-silenced lines all have an increased composition of galactose, but the transport efficiency of UDP-galactose across microsomal membranes was not altered. Taken together, these results reveal that AtAPY1 and AtAPY2 are Golgi-localized nucleotide diphosphatases and are likely to have roles in regulating UDP/GDP concentrations in the Golgi lumen.
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Affiliation(s)
- Tsan-Yu Chiu
- Section of Molecular Cell and Developmental Biology, University of Texas, Austin, TX 78712, USA
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