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Part of the book series: NATO ASI Series ((ASIH,volume 47))

Abstract

Since the discovery of the regulatory role of inositol phospholipids in animal cell signalling, there has been considerable interest in these inositol phospholipids as potential sources of second messengers in plants (Boss, 1989). In animal cells, the negatively charged phospholipid, phosphatidylinositol bisphosphate (PIP2), is present in the plasma membrane and in response to external stimuli is cleaved by phospholipase C to produce the second messengers, inositol1,4,5-trisphosphate (IP3) and diacylglycerol (DAG) (Billah and Lapetina, 1983; Berridge and Irvine, 1984; Downes and Michell, 1985; Michell, 1986; Majerus et al., 1986; Berridge, 1987). DAG activates protein kinase C (Nishizuka, 1984) and IP3 releases calcium from non-mitochondrial intracellular stores (Streb et al., 1983) thus activating calcium-dependent enzymes.

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References

  • Anderson JM (1989) Membrane-derived fatty acids as precursors to second messengers. In: Boss WF, Morré DJ (eds) Second Messengers in Plant Growth and Development. Alan R. Liss, New York, pp 181–212

    Google Scholar 

  • Anderson RA, VT Marchesi (1985) Regulation of the association of membrane skeletal protein 4.1 with glycophorin by a polyphosphoinositide. Nature 318: 295–298

    Article  PubMed  CAS  Google Scholar 

  • Berridge MJ, RF Irvine (1984) Inositol trisphosphate, a novel second messenger in cellular signal transduction. Nature 312: 315–321

    Article  PubMed  CAS  Google Scholar 

  • Berridge MJ (1987) Inositol trisphosphate and diacylglycerol: Two interacting second messengers. Ann Rev Biochem 56: 159–193

    Article  PubMed  CAS  Google Scholar 

  • Billah MM, EG Lapetina (1983) Platelet-activating factor stimulates metabolism of phosphoinositides in horse platelets: Possible relationship to Ca2+ mobilization during stimulation. Proc Natl Acad Sci USA 80: 965–968

    Article  PubMed  CAS  Google Scholar 

  • Billah MM, EG Lapetina (1982) Formation of lysophosphatidylinositol in platelets stimulated with thrombin or ionophore A23187. J Biol Chem 257: 5190–5200

    Google Scholar 

  • Blowers DP, AJ Trewavas (1989) Second Messenger: Their existence and relationship to protein kinases. In: WF Boss and DJ Morré (eds) Second Messengers in Plant Growth and Development. Alan R. Liss New York, pp 1–28

    Google Scholar 

  • Blowers DP, WF Boss, AJ Trewavas (1988) Rapid changes in plasma membrane protein phosphorylation during cell wall digestion. Plant Physiol 86: 505–509

    Article  PubMed  CAS  Google Scholar 

  • Blowers DP, AJ Trewavas (1988) Phosphatidylinositol kinase activity of a plasma membrane-associated calcium-activated protein kinase from peas. FEBS Lett 238: 87–89

    Article  CAS  Google Scholar 

  • Boss WF, MO Massel (1985) Polyphosphoinositides are present in plant tissue culture cells. Biochem Biophysics Res Commun 132: 1018–1023

    Article  CAS  Google Scholar 

  • Boss WF (1989) Phosphoinositide metabolism: Its relation to signal transduction in plants. In: Boss WF and DJ Morré (eds) Second Messengers in Plant Growth and Development. Alan R. Liss, New York, pp 29–56

    Google Scholar 

  • Brightman, AO, R Barr, FL Crane, DJ Morré (1988) Auxin-stimulated NADH oxidase purified from plasma membrane of soybean. Plant Physiol 86: 1264–1269

    Article  PubMed  CAS  Google Scholar 

  • Budde RJA, R Chollet (1988) Regulation of enzyme activity in plants by reversible phosphorylation. Physiol Plant 72: 435–439

    Article  CAS  Google Scholar 

  • Budde RJA, Randall DD (1988) Protein kinases and future prospects. In: Morré DJ, Boss WF, Loewus FA, (ed) Inositol metabolism in plants. Allan R. Liss, New York

    Google Scholar 

  • Campbell CR, JB Fishman, RE Fine (1985) Coated vesicles contain a phosphatidylinositol kinase. J Biol Chem 260: 10948–10951

    PubMed  CAS  Google Scholar 

  • Chauhan VPS, H Brocherholt (1988) Phosphatidylinositol-4,5bisphosphate may antecede diacylglycerol as activation of protein kinase C. Biochem Biophys Res Comm 155: 18–23

    Article  PubMed  CAS  Google Scholar 

  • Choquette D, E Hakim, AE Filoteo, EA Plishker, JR Bostwick, JT Penniston (1984) Regulation of plasma membrane Ca2+ ATPases by lipids of the phosphatidylinositol cycle. Biochem Biophys Res Comm 125: 908–915

    Article  PubMed  CAS  Google Scholar 

  • Collins CA, WW Wells (1983) Identification of phosphatidylinositol kinase in rat liver lysosomal membranes. J Biol Chem 258: 2130–2134

    PubMed  CAS  Google Scholar 

  • Coté GG, MJ Morse, RC Crain, RL Satter (1987) Isolation of soluble metabolites of the phosphatidylinositol cycle from Samanea saman. Plant Cell Reports 6: 352–355

    Article  Google Scholar 

  • Coté GG, LM Quarmby, RL Satter, MJ Morse, RC Crain (1988) Extraction, separation and characterization of the inositol phospholipid cycle. In: Morré DJ, Boss WF, Loewus FA, (eds) Inositol Metabolism in Plants. New York, Alan R Liss

    Google Scholar 

  • Dengler LA, M Rincón, WF Boss (1988) NBD-PC: A tool to study endocytosis in plant protoplasts. In: Morré DJ, KE Howell, GMW Cook, WH Evans (eds) Cell-Free Analysis of Membrane Traffic. New York, Alan R Liss

    Google Scholar 

  • Downes, CP, RH Michell (1985) Inositol phospholipid breakdown as a receptor-controlled generator of second messengers. In: Cohen P, MD Houslay (eds) Molecular Mechanisms of Transmembrane Signalling. Elsevier, Amsterdam, pp 3–56

    Google Scholar 

  • Dr¢bak BK, IB Ferguson, AP Dawson, RF Irvine (1988) Inosítolcontaining lipids in suspension cultured plant cells: An isotopic study. Plant Physiol 87: 217–222

    Google Scholar 

  • Einspahr KJ, TC Peeler, GA Thompson, Jr (1988) Rapid changes in polyphosphoinositide metabolism associated with the response of Dunaliella saliva to hyposmotic shock. J Biol Chem 263: 5775–5779

    PubMed  CAS  Google Scholar 

  • Elliott DC, JD Skinner (1986) Calcium-dependent, phospholipid- activated protein kinase in plants. Phytochem 25: 39–44

    Article  CAS  Google Scholar 

  • Elliott DC, YS Kokke (1987) Cross-reaction of a plant protein kinase with antiserum raised against a sequence from bovine brain protein kinase C regulatory sub-unit. Biochem Biophys Res Commun 145: 1043–1047

    Article  PubMed  CAS  Google Scholar 

  • Ettlinger C, L Lehle (1988) Auxin induces rapid changes in phosphatidylinositol metabolites. Nature 331: 176–178

    Article  PubMed  CAS  Google Scholar 

  • Favre B, G Turian (1987) Identification of a calcium-and phospholipid-dependent protein kinase (protein kinase C) in Neurospora crassa. Plant Sci 49: 15–21

    CAS  Google Scholar 

  • Ferguson MAJ, AF Williams (1988) Cell-surface anchoring of proteins via glycosyl-phosphatidylinositol structures. Ann Rev Biochem 57: 285–320

    Article  PubMed  CAS  Google Scholar 

  • Gallagher S, TW Short, PM Ray, LH Pratt, WR Briggs (1988) Light-mediated changes in two proteins associated with plasma membrane fractions from pea stem sections. Proc Natl Acad Sci USA 85: 8003–8007

    Article  PubMed  CAS  Google Scholar 

  • Grimes HD, WF Boss (1985) Intracellular calcium and calmodulin involvement in protoplast fusion. Plant Physiol 79: 253–258

    Article  PubMed  CAS  Google Scholar 

  • Harmon AC (1989) Lipid activated Protein Kinases. In: Morré DJ, Boss WF, Loewus FA, (eds) Inositol metabolism in plants. Alan R. Liss, New York

    Google Scholar 

  • Hartmann E, H Pfaffmann (1989) Mosses as a model system for involvement of phosphatidylinositol metabolism in signal transduction. In: DJ Morré, WF Boss, F Loewus (eds) Inositol Metabolism in Plants. Alan R. Liss, New York

    Google Scholar 

  • Hartmann E, H Pfaffmann (1989) Mosses as a model system for involvement of phosphatidylinositol metabolism in signal transduction. In: DJ Morré, WF Boss, F Loewus (eds) Inositol Metabolism in Plants. Alan R. Liss, New York

    Google Scholar 

  • Hartmann E, H Pfaffmann (1989) Mosses as a model system for involvement of phosphatidylinositol metabolism in signal transduction. In: DJ Morré, WF Boss, F Loewus (eds) Inositol Metabolism in Plants. Alan R. Liss, New York

    Google Scholar 

  • Jergil B, R Sundler (1983) Phosphorylation of phosphatidylinositol in rat liver Golgi. J Biol Chem 258: 7968–7973

    PubMed  CAS  Google Scholar 

  • Kiehl R, M Varsanyi, E Neumann (1987) Phosphorylation of phosphatidylinositol associated with nicotinic acetylcholine receptor of Torpedo californica. Biochem Biophys Res Comm 147: 1251–1258

    Article  PubMed  CAS  Google Scholar 

  • Klucis E, GM Polya (1987) Calcium-dependent activation of two plant leaf calcium-regulated protein kinases by unsaturated fatty acids. Biochem Biophys Res Comm 147: 1041–1047

    Article  PubMed  CAS  Google Scholar 

  • Lassing I, U Lindberg (1988) Evidence that phosphatidylinositol cycle is linked to cell motility. Exp Cell Res 174: 1–15

    Article  PubMed  CAS  Google Scholar 

  • Lassing I, Lindberg U (1985) Specific binding between phosphatidylinositol 4,5-bisphosphate and profilactin. Nature 314: 472–474

    Article  PubMed  CAS  Google Scholar 

  • Leshem YY (1987) Membrane phospholipid catabolism and Cat+ activity in control of senescence. Physiol Plant 69: 551–559

    Article  CAS  Google Scholar 

  • Lin SH, JN Fain (1985) Calcium-magnesium ATPase in rat hepatocyte plasma membranes: inhibition by vasopressin and purification of the enzyme. Prog Clin Biol Res 168: 25–30

    Google Scholar 

  • Lipsky JJ, PS Lietman (1980) Neomycin Inhibition of Adenosine triphosphatase: Evidence for a neomycin phospholipid interaction. Antimicrobial Agents and chemotherapy 18: 532–535

    Google Scholar 

  • Loewus FA, MW Loewus (1983) myo-Inositol: Its biosynthesis and metabolism. Annu Rev Plant Physiol 34: 137–161

    Google Scholar 

  • Low MG, PW Kincade (1985) Phosphatidylinositol is the membrane-anchoring domain of the thy-1 glycoprotein. Nature 318: 62–64

    Article  PubMed  CAS  Google Scholar 

  • Low MG, AR Saltiel (1988) Structural and functional roles of glycosyl-phosphatidylinositol in membranes. Science 239: 268–275

    Article  PubMed  CAS  Google Scholar 

  • Lucantoni A, GM Polya (1987) Activation of wheat embryo calcium-regulated protein kinase by unsaturated fatty acids in the presence and absence of calcium. FEBS Lett 221: 33–36

    Article  CAS  Google Scholar 

  • Macara, IG (1980) Vanadium-an element in search of a role. Trends in Biochem Sci 5: 92–94

    Article  CAS  Google Scholar 

  • Majerus PW, TM Connolly, H Deckmyn, TS Ross, TE Bross, H Ishii, VS Bansal, DB Wilson (1986) The metabolism of phosphoinositide-derived messenger molecules. Science 234: 1519–1526

    Article  PubMed  CAS  Google Scholar 

  • Margolis BL, B Holub, DA Troyer, KL Skorecki (1988) Epidermal growth factor stimulates phospholipase A2 in vasopressintreated rat glomerular mesangial cells. Biochem J 256: 469–474

    PubMed  CAS  Google Scholar 

  • Marthiny-Baron G, GFE Scherer (1988) A plant protein kinase and plant microsomal H+ transport are stimulated by the ether phospholipid. platelet-activating factor. Plant Cell Rep 7: 579–582

    Article  Google Scholar 

  • Melin PM, M Sommarin, AS Sandelius, B Jergil (1987) Identification of Cat+-stimulated polyphosphoinositide phospholipase C in isolated plant plasma membranes. FEBS Lett 223: 87–91

    Article  PubMed  CAS  Google Scholar 

  • Melin PM, M Sommarin, AS Sandelius, B Jergil (1987) Identification of Cat+-stimulated polyphosphoinositide phospholipase C in isolated plant plasma membranes. FEBS Lett 223: 87–91

    Article  PubMed  CAS  Google Scholar 

  • Michell RH (1986) Inositol lipids and their role in receptor function: History and general principles. In: Putney JW, Jr. (ed) Receptor Biochemistry and Methodology, Phosphoinositide and Receptor Mechanisms. Vol 7, Alan R Liss Inc, New York, pp 1–24

    Google Scholar 

  • Morré DJ (1989) Stimulus-response coupling in auxin regulation of plant cell elongation. In: Boss WF and DJ Morré (eds) Second Messengers in Plant Growth and Development. Alan R Liss, New York pp 29–56

    Google Scholar 

  • Morré DJ, B Gripshover, A Monroe, JT Morré (1984a) Phosphatidylinositol turnover in isolated soybean membranes stimulated by the synthetic growth hormone 2,4dichlorophenoxyacetic acid. J Biol Chem 259: 15364–15368

    PubMed  Google Scholar 

  • Morré DJ, JT Morré RL Varnold (1984b) Phosphorylation of membrane located proteins of soybean in vitro and response to auxin. Plant Physiol 75: 265–268

    Article  PubMed  Google Scholar 

  • Morré DJ, B Drobes, H Pfaffmann, FE Wilkinson, E Hartmann (1989) Diacylglycerol levels unchanged during auxin-stimulated growth of excised hypocotyl segments of soybean. Plant Physiol 90: 275–279

    Article  PubMed  Google Scholar 

  • Morse MJ, RC Crain, GG Coté, RL Satter (1989a) Light-stimulated inositol phospholipid turnover in Samanea saman pulvini. Increased levels of diacylglycerol. Plant Physiol 89: 724–727

    Google Scholar 

  • Morse MJ, RC Crain, GG Coté, RL Satter (1989b) Light-signal transduction via accelerated inositol phospholipid turnover in Samanea saman pulvini. In: Morré DJ, WF Boss, FA Loewus (eds) Inositol Metabolism in Plants. Alan R Liss, New York

    Google Scholar 

  • Morse MJ, RC Crain, RL Satter (1987) Light-stimulated inositol phospholipid turnover in Samanea saman leaf pulvini. Proc Natl Acad Sci USA 84: 7075–7078

    Article  PubMed  CAS  Google Scholar 

  • Murthy WC, RF Irvine (1988) Phosphatidylinositol 4,5bisphosphate phosphodiesterase in higher plants. Biochem J. 249; 877–881

    Google Scholar 

  • Nishizuka Y (1984) Turnover of inositol phospholipids and signal transduction. Science 225: 1365–1370

    Article  PubMed  CAS  Google Scholar 

  • Olah Z, Z Kiss (1986) Occurrence of lipid and phorbol ester activated protein kinase in wheat cells. FEBS Lett 195: 33–37

    Article  CAS  Google Scholar 

  • Palmgren MG, M Sommarin, P Ulvskov, PL Jorgenson (1988) Modulation of plasma membrane H+ ATPase from oat roots by lysophosphatidylcholine, free fatty acids and phospholipase A2. Physiologia Plantarum 74: 11–19

    Article  CAS  Google Scholar 

  • Peeler TC and GA Thompson, Jr (1989) Effects of light on inositol phospholipid metabolism in Dunaliella saliva. Plant Physiol 89S: 895

    Article  Google Scholar 

  • Pelech SL, DE Vance (1989) Signal transduction via phosphatidylcholine cycles. Trends in Biochem Sci 14: 29–30

    Article  Google Scholar 

  • Pfaffmann H, E Hartmann, AO Brightman, DJ Morré (1987) Phosphatidylinositol specific phospholipase C of plant stems: Membrane associated activity concentrated in plasma membranes. Plant Physiol 85: 1151–1155

    Google Scholar 

  • Ranjeva R, G Refeno, AM Boudet, D Marmé (1983) Activation of plant quinate:NAD 3-oxidoreductase by Cat+ and calmodulin. Proc Natl Acad Sci 80: 5222–5224

    Article  PubMed  CAS  Google Scholar 

  • Ranjeva R, AM Boudet (1987) Phosphorylation of proteins in plants: regulatory effects and potential involvement in stimulus/response coupling. Annu Rev Plant Physiol 38: 73–93

    Article  CAS  Google Scholar 

  • Ranjeva R, A Carrasco, AM Boudet (1988) Inositol trisphosphate stimulates the release of calcium from intact vacuoles isolated from Acer cells. FEES Lett 230: 137–141

    Article  CAS  Google Scholar 

  • Reddy ASN, BW Poovaiah (1987) Inositol 1,4,5-trisphosphate induced calcium release from corn coleoptile microsomes. J Biochem 101: 569–573

    Article  PubMed  CAS  Google Scholar 

  • Rincón M, Q Chen, WF Boss (1989) Characterization of inositol phosphates in carrot (Daucus carota L.) cells. Plant Physiol. 89: 126–132

    Article  PubMed  Google Scholar 

  • Rincón M, Boss WF (1989) The second messenger role of Phosphoinositides. In: Morré DJ, Boss WF, Loewus FA, (eds) Inositol Metabolism in Plants. Alan R. Liss, New York

    Google Scholar 

  • Rincón M, WF Boss (1987) myo-Inositol trisphosphate mobilizes calcium from fusogenic carrot (Daucus carota L.) protoplasts. Plant Physiol 83: 395–398

    Google Scholar 

  • Saltiel, AR. JA Fox, P Sherline, N Sahyoun, P Cuatrecasas (1987) Purification of phosphatidylinositol kinase from rat brain myelin. Biochem J 241: 759–763

    PubMed  CAS  Google Scholar 

  • Sandelius AS, DJ Morré (1987) Characteristics of phosphatidylinositol exchange activity of soybean microsomes. Plant Physiol 84: 1022–1027

    Article  PubMed  CAS  Google Scholar 

  • Sandelius AS, M Sommarin (1986) Phosphorylation of phosphatidylinositols in isolated plant membranes FEBS Lett 201: 282–286

    CAS  Google Scholar 

  • Sandelius AS, M Sommarin (1989) Membrane-localized reactions involved in polyphosphoinositide turnover. In: Morré DJ, Boss WF, Loewus FA, (eds) Inositol Metabolism in Plants. Alan R Liss, New York

    Google Scholar 

  • Schäfer A, F Bygrave, S Matzenauer, D Marmé (1985) Identification of a calcium and phospholipid-dependent protein kinase in plant tissue. FEES Lett 187: 25–28

    Article  Google Scholar 

  • Schäfer M, G Behle, M Varsanyi, LMG Heilmeyer, Jr (1987) Cat+ regulation of 1- (3-sn-phosphatidyl) -1D-myo-inositol 4-phosphate formation and hydrolysis on sarcoplasmic-reticular Cat+-transport ATPase: A new principle of phospholipid turnover regulation. Biochem J 247: 579–587

    Google Scholar 

  • Scherer GFE, G Martiny-Baron, B Stoffel (1988) A new set of regulatory molecules in plants: A plant phospholipid similar to platelet activating factor stimulates protein kinase and proton-translocating ATPase in membrane vesicles. Planta 175: 241–253

    Google Scholar 

  • Schumaker KS, H Sze (1987) Inositol 1,4,5-trisphosphate releases Cat+ from vacuolar membrane vesicles of oat roots. J Biol Chem 262: 3944–3946

    PubMed  CAS  Google Scholar 

  • Smith CD, WW Wells (1983) Phosphorylation of rat liver nuclear envelopes II. Characterization of in vitro lipid phosphorylation. J Biol Chem 258: 9368–9373

    Google Scholar 

  • Sommarin M, AS Sandelius (1987) Phosphatidylinositol and phosphatidylinositol phosphate kinases in plant plasma membranes. Biochim Biophys Acta 958: 268–278

    Google Scholar 

  • Stephenson M, PE Ryals, GA Thompson, Jr (1989) Fatty acid acylated proteins of the halotolerant alga Dunaliella saliva. Plant Physiol 90: 549–552

    Article  PubMed  CAS  Google Scholar 

  • Strasser H, C Hoffman, H Grisebach, U Matern (1986) Are polyphosphoinositides involved in signal transduction of elicitor-induced phytoalexin synthesis in cultured plant cells? Z. Naturforsch 41c: 717–724

    CAS  Google Scholar 

  • Streb H, RF Irvine, MJ Berridge, I Schulz (1983) Release of Cat+ from a nonmitochondrial intracellular store in pancreatic acinar cells by inositol-1,4,5-trisphosphate. Nature 306: 67–68

    Article  PubMed  CAS  Google Scholar 

  • Torruella M, LM Casano, RH Vallejos (1986) Evidence of activity of tyrosine kinase(s) and of the presence of phosphotyrosine in pea plantlets. J Biol Chem 261: 6651–6653

    PubMed  CAS  Google Scholar 

  • Varsanyi M, HG Tolle, LMG Heilmeyer, Jr, RMC Dawson RF Irvine (1983) Activation of sarcoplasmic reticular Ca21- transport ATPase by phosphorylation of an associated phosphatidylinositol. EMBO J 2: 1543–1548

    PubMed  CAS  Google Scholar 

  • Wheeler JJ, Boss WF (1989) Inositol lysophospholipids. In: Morré DJ,Boss WF, Loewus FA, (eds) Inositol Metabolism in Plants. Alan R Liss, New York

    Google Scholar 

  • Wheeler JJ, WF Boss (1987) Polyphosphoinositides are present in plasma membrane from fusogenic carrot cells. Plant Physiol 85: 389–392

    Article  PubMed  CAS  Google Scholar 

  • Whitman M, D Kaplan, T Roberts, L Cantley (1987) Evidence for two distinct phosphatidylinositol kinases in fibroblasts. Biochem J. 247: 165–174

    PubMed  CAS  Google Scholar 

  • Zbell B, G Walter (1987) About the search for the molecular action of high affinity auxin-binding sites on membrane-localized rapid phosphoinositide metabolism in plant cells. In: KlAmbt D (ed) Plant Hormone Receptors. Springer-Verlag, Berlin pp 141–153

    Chapter  Google Scholar 

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Boss, W.F., Memon, A.R., Chen, Q. (1990). Phospholipid Derived Messengers. In: Ranjeva, R., Boudet, A.M. (eds) Signal Perception and Transduction in Higher Plants. NATO ASI Series, vol 47. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-83974-0_13

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