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Wang Y, Wakelam MJO, Bankaitis VA, McDermott MI. The wide world of non-mammalian phospholipase D enzymes. Adv Biol Regul 2024; 91:101000. [PMID: 38081756 DOI: 10.1016/j.jbior.2023.101000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 02/25/2024]
Abstract
Phospholipase D (PLD) hydrolyses phosphatidylcholine (PtdCho) to produce free choline and the critically important lipid signaling molecule phosphatidic acid (PtdOH). Since the initial discovery of PLD activities in plants and bacteria, PLDs have been identified in a diverse range of organisms spanning the taxa. While widespread interest in these proteins grew following the discovery of mammalian isoforms, research into the PLDs of non-mammalian organisms has revealed a fascinating array of functions ranging from roles in microbial pathogenesis, to the stress responses of plants and the developmental patterning of flies. Furthermore, studies in non-mammalian model systems have aided our understanding of the entire PLD superfamily, with translational relevance to human biology and health. Increasingly, the promise for utilization of non-mammalian PLDs in biotechnology is also being recognized, with widespread potential applications ranging from roles in lipid synthesis, to their exploitation for agricultural and pharmaceutical applications.
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Affiliation(s)
- Y Wang
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA; Department of Microbiology, University of Washington, Seattle, WA98109, USA
| | - M J O Wakelam
- Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom
| | - V A Bankaitis
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA; Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX, 77843, USA; Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - M I McDermott
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA.
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2
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Deepika D, Singh A. Plant phospholipase D: novel structure, regulatory mechanism, and multifaceted functions with biotechnological application. Crit Rev Biotechnol 2021; 42:106-124. [PMID: 34167393 DOI: 10.1080/07388551.2021.1924113] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Phospholipases D (PLDs) are important membrane lipid-modifying enzymes in eukaryotes. Phosphatidic acid, the product of PLD activity, is a vital signaling molecule. PLD-mediated lipid signaling has been the subject of extensive research leading to discovery of its crystal structure. PLDs are involved in the pathophysiology of several human diseases, therefore, viewed as promising targets for drug design. The availability of a eukaryotic PLD crystal structure will encourage PLD targeted drug designing. PLDs have been implicated in plants response to biotic and abiotic stresses. However, the molecular mechanism of response is not clear. Recently, several novel findings have shown that PLD mediated modulation of structural and developmental processes, such as: stomata movement, root growth and microtubule organization are crucial for plants adaptation to environmental stresses. Involvement of PLDs in regulating membrane remodeling, auxin mediated alteration of root system architecture and nutrient uptake to combat nitrogen and phosphorus deficiencies and magnesium toxicity is established. PLDs via vesicle trafficking modulate cytoskeleton and exocytosis to regulate self-incompatibility (SI) signaling in flowering plants, thereby contributes to plants hybrid vigor and diversity. In addition, the important role of PLDs has been recognized in biotechnologically important functions, including oil/TAG synthesis and maintenance of seed quality. In this review, we describe the crystal structure of a plant PLD and discuss the molecular mechanism of catalysis and activity regulation. Further, the role of PLDs in regulating plant development under biotic and abiotic stresses, nitrogen and phosphorus deficiency, magnesium ion toxicity, SI signaling and pollen tube growth and in important biotechnological applications has been discussed.
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Affiliation(s)
- Deepika Deepika
- National Institute of Plant Genome Research, New Delhi, India
| | - Amarjeet Singh
- National Institute of Plant Genome Research, New Delhi, India
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3
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Kaur A, Neelam K, Kaur K, Kitazumi A, de Los Reyes BG, Singh K. Novel allelic variation in the Phospholipase D alpha1 gene (OsPLDα1) of wild Oryza species implies to its low expression in rice bran. Sci Rep 2020; 10:6571. [PMID: 32313086 PMCID: PMC7170842 DOI: 10.1038/s41598-020-62649-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 03/16/2020] [Indexed: 11/25/2022] Open
Abstract
Rice bran, a by-product after milling, is a rich source of phytonutrients like oryzanols, tocopherols, tocotrienols, phytosterols, and dietary fibers. Moreover, exceptional properties of the rice bran oil make it unparalleled to other vegetable oils. However, a lipolytic enzyme Phospholipase D alpha1 (OsPLDα1) causes rancidity and ‘stale flavor’ in the oil, and thus limits the rice bran usage for human consumption. To improve the rice bran quality, sequence based allele mining at OsPLDα1 locus (3.6 Kb) was performed across 48 accessions representing 11 wild Oryza species, 8 accessions of African cultivated rice, and 7 Oryza sativa cultivars. From comparative sequence analysis, 216 SNPs and 30 InDels were detected at the OsPLDα1 locus. Phylogenetic analysis revealed 20 OsPLDα1 cDNA variants which further translated into 12 protein variants. The O. officinalis protein variant, when compared to Nipponbare, showed maximum variability comprising 22 amino acid substitutions and absence of two peptides and two β-sheets. Further, expression profiling indicated significant differences in transcript abundance within as well as between the OsPLDα1 variants. Also, a new OsPLDα1 transcript variant having third exon missing in it, Os01t0172400-06, has been revealed. An O. officinalis accession (IRGC101152) had lowest gene expression which suggests the presence of novel allele, named as OsPLDα1-1a (GenBank accession no. MF966931). The identified novel allele could be further deployed in the breeding programs to overcome rice bran rancidity in elite cultivars.
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Affiliation(s)
- Amandeep Kaur
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, Punjab, India.,School of Biology and Ecology, University of Maine, Orono, Maine, United States of America
| | - Kumari Neelam
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, Punjab, India
| | - Karminderbir Kaur
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, Punjab, India
| | - Ai Kitazumi
- School of Biology and Ecology, University of Maine, Orono, Maine, United States of America.,Department of Plant and Soil Science, Texas Tech University, Lubbock, Texas, United States of America
| | - Benildo G de Los Reyes
- School of Biology and Ecology, University of Maine, Orono, Maine, United States of America.,Department of Plant and Soil Science, Texas Tech University, Lubbock, Texas, United States of America
| | - Kuldeep Singh
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, Punjab, India. .,ICAR- National Bureau of Plant Genetic Resources, New Delhi, India.
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Arhab Y, Abousalham A, Noiriel A. Plant phospholipase D mining unravels new conserved residues important for catalytic activity. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:688-703. [DOI: 10.1016/j.bbalip.2019.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/09/2019] [Accepted: 01/13/2019] [Indexed: 01/16/2023]
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5
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Dreßler L, Michel F, Thondorf I, Mansfeld J, Golbik R, Ulbrich-Hofmann R. Metal ions and phosphatidylinositol 4,5-bisphosphate as interacting effectors of α-type plant phospholipase D. PHYTOCHEMISTRY 2017; 138:57-64. [PMID: 28283189 DOI: 10.1016/j.phytochem.2017.02.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/02/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
Plant phospholipases D (PLD) are typically characterized by a C2 domain with at least two Ca2+ binding sites. In vitro, the predominantly expressed α-type PLDs need 20-100 mM CaCl2 for optimum activity, whereas the essential activator of β- or γ-type PLDs, phosphatidylinositol 4,5-bisphosphate (PIP2), plays a secondary role. In the present paper, we have studied the interplay between PIP2 and metal ion activation of the well-known α-type PLD from cabbage (PLDα). With mixed micelles containing phosphatidyl-p-nitrophenol as substrate, PIP2-concentrations in the nanomolar range are able to activate the enzyme in addition to the essential Ca2+ activation. Mg2+ ions are able to replace Ca2+ ions but they do not activate PLDα. Rather, they abolish the activation of the enzyme by Ca2+ ions in the absence, but not in the presence, of PIP2. The presence of PIP2 causes a shift in the pH optimum of PLDα activity to the acidic range. Employing fluorescence measurements and replacing Ca2+ by Tb3+ ions, confirmed the presence of two metal ion-binding sites, in which the one of lower affinity proved crucial for PLD activation. Moreover, we have generated a homology model of the C2 domain of this enzyme, which was used for Molecular Dynamics (MD) simulations and docking studies. As is common for C2 domains, it shows two antiparallel β-sheets consisting of four β-strands each and loop regions that harbor two Ca2+ binding sites. Based on the findings of the MD simulation, one of the bound Ca2+ ions is coordinated by five amino acid residues. The second Ca2+ ion induces a loop movement upon its binding to three amino acid residues. Docking studies with PIP2 reveal, in addition to the previously postulated PIP2-binding site in the middle of the β-sheet structure, another PIP2-binding site near the two Ca2+ ions, which is in accordance with the experimental interplay of PIP2, Ca2+ and Mg2+ ions.
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Affiliation(s)
- Lars Dreßler
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Florian Michel
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Iris Thondorf
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Johanna Mansfeld
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Ralph Golbik
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Renate Ulbrich-Hofmann
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany.
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Han EH, Petrella DP, Blakeslee JJ. 'Bending' models of halotropism: incorporating protein phosphatase 2A, ABCB transporters, and auxin metabolism. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3071-3089. [PMID: 28899081 DOI: 10.1093/jxb/erx127] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Salt stress causes worldwide reductions in agricultural yields, a problem that is exacerbated by the depletion of global freshwater reserves and the use of contaminated or recycled water (i.e. effluent water). Additionally, salt stress can occur as cultivated areas are subjected to frequent rounds of irrigation followed by periods of moderate to severe evapotranspiration, which can result in the heterogeneous aggregation of salts in agricultural soils. Our understanding of the later stages of salt stress and the mechanisms by which salt is transported out of cells and roots has greatly improved over the last decade. The precise mechanisms by which plant roots perceive salt stress and translate this perception into adaptive, directional growth away from increased salt concentrations (i.e. halotropism), however, are not well understood. Here, we provide a review of the current knowledge surrounding the early responses to salt stress and the initiation of halotropism, including lipid signaling, protein phosphorylation cascades, and changes in auxin metabolism and/or transport. Current models of halotropism have focused on the role of PIN2- and PIN1-mediated auxin efflux in initiating and controlling halotropism. Recent studies, however, suggest that additional factors such as ABCB transporters, protein phosphatase 2A activity, and auxin metabolism should be included in the model of halotropic growth.
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Affiliation(s)
- Eun Hyang Han
- Department of Horticulture and Crop Science, The Ohio State University/OARDC, Wooster, OH, USA
| | - Dominic P Petrella
- Department of Horticulture and Crop Science, The Ohio State University/OARDC, Wooster, OH, USA
| | - Joshua J Blakeslee
- Department of Horticulture and Crop Science, OARDC Metabolite Analysis Cluster (OMAC), The Ohio State University/OARDC, Wooster, OH, USA
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Functional Characterization of the N-Terminal C2 Domain from Arabidopsis thaliana Phospholipase D α and D β. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2721719. [PMID: 28101506 PMCID: PMC5215601 DOI: 10.1155/2016/2721719] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/06/2016] [Accepted: 10/27/2016] [Indexed: 11/17/2022]
Abstract
Most of plant phospholipases D (PLD) exhibit a C2-lipid binding domain of around 130 amino acid residues at their N-terminal region, involved in their Ca2+-dependent membrane binding. In this study, we expressed and partially purified catalytically active PLDα from Arabidopsis thaliana (AtPLDα) in the yeast Pichia pastoris. The N-terminal amino acid sequence of the recombinant AtPLDα was found to be NVEETIGV and thus to lack the first 35 amino acid belonging to the C2 domain, as found in other recombinant or plant purified PLDs. To investigate the impact of such a cleavage on the functionality of C2 domains, we expressed, in E. coli, purified, and refolded the mature-like form of the C2 domain of the AtPLDα along with its equivalent C2 domain of the AtPLDβ, for the sake of comparison. Using Förster Resonance Energy Transfer and dot-blot assays, both C2 domains were shown to bind phosphatidylglycerol in a Ca2+-independent manner while phosphatidic acid and phosphatidylserine binding were found to be enhanced in the presence of Ca2+. Amino acid sequence alignment and molecular modeling of both C2 domains with known C2 domain structures revealed the presence of a novel Ca2+-binding site within the C2 domain of AtPLDα.
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8
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Hong Y, Zhao J, Guo L, Kim SC, Deng X, Wang G, Zhang G, Li M, Wang X. Plant phospholipases D and C and their diverse functions in stress responses. Prog Lipid Res 2016; 62:55-74. [DOI: 10.1016/j.plipres.2016.01.002] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 12/23/2015] [Accepted: 01/01/2016] [Indexed: 12/25/2022]
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9
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Khatoon H, Mansfeld J, Schierhorn A, Ulbrich-Hofmann R. Purification, sequencing and characterization of phospholipase D from Indian mustard seeds. PHYTOCHEMISTRY 2015; 117:65-75. [PMID: 26057230 DOI: 10.1016/j.phytochem.2015.05.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/15/2015] [Accepted: 05/27/2015] [Indexed: 06/04/2023]
Abstract
Phospholipase D (PLD; E.C. 3.1.4.4) is widespread in plants where it fulfills diverse functions in growth and in the response to stresses. The enzyme occurs in multiple forms that differ in their biochemical properties. In the present paper PLD from medicinally relevant Indian mustard seeds was purified by Ca(2+)-mediated hydrophobic interaction and anion exchange chromatography to electrophoretic homogeneity. Based on mass-spectrometric sequence analysis of tryptic protein fragments, oligonucleotide primers for cloning genomic DNA fragments that encoded the enzyme were designed and used to derive the complete amino acid sequence of this PLD. The sequence data, as well as the molecular properties (molecular mass of 92.0 kDa, pI 5.39, maximum activity at pH 5.5-6.0 and Ca(2+) ion concentrations ⩾60 mM), allowed the assignment of this enzyme to the class of α-type PLDs. The apparent kinetic parameters Vmax and Km, determined for the hydrolysis of phosphatidylcholine (PC) in an aqueous mixed-micellar system were 356±15 μmol min(-1) mg(-1) and 1.84±0.17 mM, respectively. Phosphate analogs such as NaAlF4 and Na3VO4 displayed strong inhibition of the enzyme. Phosphatidylinositol 4,5-bisphosphate had a strong activating effect at 2-10 mM CaCl2. PLD was inactivated at temperatures >45 °C. The enzyme exhibited the highest activity toward PC followed by phosphatidylethanolamine and phosphatidylglycerol. PCs with short-chain fatty acids were better substrates than PCs with long fatty acid chains. Lyso-PC was not accepted as substrate.
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Affiliation(s)
- Hafeeza Khatoon
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06120 Halle, Germany
| | - Johanna Mansfeld
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06120 Halle, Germany
| | - Angelika Schierhorn
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06120 Halle, Germany
| | - Renate Ulbrich-Hofmann
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06120 Halle, Germany.
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10
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Jiang Y, Wu K, Lin F, Qu Y, Liu X, Zhang Q. Phosphatidic acid integrates calcium signaling and microtubule dynamics into regulating ABA-induced stomatal closure in Arabidopsis. PLANTA 2014; 239:565-75. [PMID: 24271006 DOI: 10.1007/s00425-013-1999-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 11/11/2013] [Indexed: 05/20/2023]
Abstract
Specific cellular components have been identified to function in abscisic acid (ABA) regulation of stomatal apertures, including calcium, the cytoskeleton, and phosphatidic acid. In this study, the regulation and dynamic organization of microtubules during ABA-induced stomatal closure by phospholipase D (PLD) and its product PA were investigated. ABA induced microtubule depolymerization and stomatal closure in wide-type (WT) Arabidopsis, whereas these processes were impaired in PLD mutant (pldα1). The microtubule-disrupting drugs oryzalin or propyzamide induced microtubule depolymerization, but did not affect the stomatal aperture, whereas their co-treatment with ABA resulted in stomatal closure in both WT and pldα1. In contrast, the microtubule-stabilizing drug paclitaxel arrested ABA-induced microtubule depolymerization and inhibited ABA-induced stomatal closure in both WT and pldα1. In pldα1, ABA-induced cytoplasmic Ca(2+) ([Ca(2+)]cyt) elevation was partially blocked, and exogenous Ca(2+)-induced microtubule depolymerization and stomatal closure were impaired. These results suggested that PLDα1 and PA regulate microtubular organization and Ca(2+) increases during ABA-induced stomatal closing and that crosstalk among signaling lipid, Ca(2+), and microtubules are essential for ABA signaling.
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Affiliation(s)
- Yan Jiang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
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12
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Agrawal L, Narula K, Basu S, Shekhar S, Ghosh S, Datta A, Chakraborty N, Chakraborty S. Comparative Proteomics Reveals a Role for Seed Storage Protein AmA1 in Cellular Growth, Development, and Nutrient Accumulation. J Proteome Res 2013; 12:4904-30. [DOI: 10.1021/pr4007987] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lalit Agrawal
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Kanika Narula
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Swaraj Basu
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Shubhendu Shekhar
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Sudip Ghosh
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Asis Datta
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Niranjan Chakraborty
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
| | - Subhra Chakraborty
- Laboratory 104 and ‡Laboratory 105, National Institute of Plant Genome Research, Aruna
Asaf Ali Marg, New Delhi 110067, India
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Abstract
Over the past decade, tremendous progress has been made toward understanding the physiological functions of individual members of the diverse phospholipase D (PLD) family of enzymes in plants. For instance, the involvement of plant PLD members has been shown or suggested in a wide variety of the cellular and physiological processes such as regulating stomatal opening and closure; signaling plant responses to drought, salt, and other abiotic and biotic stresses; organizing microtubule and actin cytoskeletal structures; promoting pollen tube growth; cycling phosphorus; signaling nitrogen availability; regulating N-acylethanolamine stress signaling; and remodeling membrane phospholipids in plant responses to phosphate deprivation and during and after freezing. There are at least a dozen PLDs in Arabidopsis that can be separated into six classes, phospholipases Dα, Dβ, Dγ, Dδ, Dε, and Dζ, based on their molecular and enzymatic characteristics. Several of the classes have distinguishing enzymatic properties that can be used to discriminate among the various classes. Here we provide four variations of in vitro PLD activity assays using choline-labeled phosphatidylcholine to distinguish, to the extent possible, among the different PLD classes.
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Zhao J, Wang X. Biochemical analysis of the interaction between phospholipase Dα1 and GTP-binding protein α-subunit from Arabidopsis thaliana. Methods Mol Biol 2013; 1043:21-35. [PMID: 23913032 DOI: 10.1007/978-1-62703-532-3_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Phospholipase Ds (PLDs) play diverse roles in plant lipid metabolism and cellular signaling processes. The sole canonical G-protein α-subunit (Gα) in Arabidopsis also plays multiple roles in plant growth and cellular signaling processes. Interestingly, overlapping functions of PLD and Gα have been indicated in many cellular processes, including abscisic acid (ABA)-mediated stomata movement and water loss, gibberellic acid (GA)-regulated seed germination, and auxin signaling. This interaction between PLD and Gα has also been suggested in biochemical and physiological studies. Here we described the methods used for studying the interaction between the major PLD form PLDα1 and Gα. From pulldown experiments with purified bacterially expressed PLDα1 and Gα, co-immunoprecipitation of plant protein extract, and yeast two-hybrid assay, we showed that there is a physical interaction between PLDα1 and Gα, and identified a key DRY motif in PLDα1, which is an essential element for the interaction. The interaction of PLDα1 and Gα can be affected by factors like GTP or GDP, but it also affected PLD phospholipase activity and Gα GTPase activity in turn.
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Affiliation(s)
- Jian Zhao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
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15
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Abstract
Plant phospholipases can be grouped into four major types, phospholipase D, phospholipase C, phospholipase A1 (PLA(1)), and phospholipase A2 (PLA(2)), that hydrolyze glycerophospholipids at different ester bonds. Within each type, there are different families or subfamilies of enzymes that can differ in substrate specificity, cofactor requirement, and/or reaction conditions. These differences provide insights into determining the cellular function of specific phospholipases in plants, and they can be explored for different industrial applications.
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Affiliation(s)
- Geliang Wang
- Department of Biology, University of Missouri, St. Louis, MO, USA
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Selvy PE, Lavieri RR, Lindsley CW, Brown HA. Phospholipase D: enzymology, functionality, and chemical modulation. Chem Rev 2011; 111:6064-119. [PMID: 21936578 PMCID: PMC3233269 DOI: 10.1021/cr200296t] [Citation(s) in RCA: 269] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Paige E Selvy
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37064, USA
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Moreno-Pérez AJ, Martínez-Force E, Garcés R, Salas JJ. Phospholipase Dalpha from sunflower (Helianthus annuus): cloning and functional characterization. JOURNAL OF PLANT PHYSIOLOGY 2010; 167:503-511. [PMID: 20116883 DOI: 10.1016/j.jplph.2009.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 11/04/2009] [Accepted: 11/05/2009] [Indexed: 05/28/2023]
Abstract
D type phospholipases (PLD) are enzymes that hydrolyze the head group of phospholipids to produce phosphatidic acid. This activity is ubiquitous in plant tissues, and has been isolated and characterized from different species and organs. Several families of these proteins have been described in plants on the basis of their gene sequences (PLD alpha, beta, gamma, delta, zeta and epsilon). They have been shown to be involved in many metabolic events, such as response to abiotic stress, signal transduction, and membrane lipid turnover and degradation. In the present study, PLD activity was measured in the soluble fractions isolated from different organs of this plant. A PLD of alpha type was cloned from leaf cDNA that was responsible for most of this activity. The gene encoding this 810 aa protein was heterologously expressed in E. coli. This protein was not lethal for the eukaryotic host, although it altered its phospholipid profile. PLDalpha was purified to almost homogeneity by His-tag affinity chromatography, displaying an optimum pH of 6.5 and strong dependence on the presence of Ca(2+) and SDS in the assay medium. The enzyme was active towards phosphatidylcholine, Phosphatidylethanolamine and phosphatidylglycerol. Furthermore, the HaPLDalpha gene was found to be expressed at high levels in leaf and stem tissues.
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Affiliation(s)
- A J Moreno-Pérez
- Instituto de la Grasa (CSIC), Av. Padre García Tejero 4, 41012 Sevilla, Spain
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19
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Mansfeld J, Ulbrich-Hofmann R. Modulation of phospholipase D activity in vitro. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:913-26. [DOI: 10.1016/j.bbalip.2009.03.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Revised: 03/03/2009] [Accepted: 03/04/2009] [Indexed: 11/30/2022]
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Phospholipase D- and phosphatidic acid-mediated signaling in plants. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:927-35. [DOI: 10.1016/j.bbalip.2009.02.017] [Citation(s) in RCA: 195] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Revised: 02/24/2009] [Accepted: 02/26/2009] [Indexed: 12/12/2022]
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Bargmann BOR, Laxalt AM, ter Riet B, Testerink C, Merquiol E, Mosblech A, Leon-Reyes A, Pieterse CMJ, Haring MA, Heilmann I, Bartels D, Munnik T. Reassessing the role of phospholipase D in the Arabidopsis wounding response. PLANT, CELL & ENVIRONMENT 2009; 32:837-50. [PMID: 19220780 DOI: 10.1111/j.1365-3040.2009.01962.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Plants respond to wounding by means of a multitude of reactions, with the purpose of stifling herbivore assault. Phospholipase D (PLD) has previously been implicated in the wounding response. Arabidopsis (Arabidopsis thaliana) AtPLDalpha1 has been proposed to be activated in intact cells, and the phosphatidic acid (PA) it produces to serve as a precursor for jasmonic acid (JA) synthesis and to be required for wounding-induced gene expression. Independently, PLD activity has been reported to have a bearing on wounding-induced MAPK activation. However, which PLD isoforms are activated, where this activity takes place (in the wounded or non-wounded cells) and what exactly the consequences are is a question that has not been comprehensively addressed. Here, we show that PLD activity during the wounding response is restricted to the ruptured cells using (32)P(i)-labelled phospholipid analyses of Arabidopsis pld knock-out mutants and PLD-silenced tomato cell-suspension cultures. pldalpha1 knock-out lines have reduced wounding-induced PA production, and the remainder is completely eliminated in a pldalpha1/delta double knock-out line. Surprisingly, wounding-induced protein kinase activation, AtLOX2 gene expression and JA biosynthesis were not affected in these knock-out lines. Moreover, larvae of the Cabbage White butterfly (Pieris rapae) grew equally well on wild-type and the pld knock-out mutants.
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Affiliation(s)
- Bastiaan O R Bargmann
- Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, NL, Amsterdam, the Netherlands
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22
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Yu ZL, Zhang JG, Wang XC, Chen J. Excessive copper induces the production of reactive oxygen species, which is mediated by phospholipase D, nicotinamide adenine dinucleotide phosphate oxidase and antioxidant systems. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2008; 50:157-67. [PMID: 18713437 DOI: 10.1111/j.1744-7909.2007.00609.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu2+. Treatment with 100 micromol/L Cu2+ generated a large amount of H2O2 and thiobarbituric acid-reactive substances (TBARS) in cells. Using phospholipase D (PLD) specific inhibitor (1-butanol) or phosphatidic acid (PA), we demonstrated that PLD plays an important role in the generation of H2O2 and TBARS. Semi-quantitative reverse-transcriptase polymerase chain reaction and enzyme activity assays with wild type and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-overexpressing BY-2 cells revealed that PLD and PA are the key factors leading to NADPH oxidase activation, which is responsible for H2O2 and TBARS production induced by Cu2+. Moreover, the content of ascorbic acid (AsA), an effective antioxidant, was sharply reduced in BY-2 cells exposed to excessive Cu2+. Furthermore, a significant downregulation of the enzymes of AsA biosynthesis and the antioxidant system was found. This evidence suggests that excessive Cu2+-elevated reactive oxygen species (ROS) production is caused by upregulated PLD that elevates the activity of NADPH oxidase and its collapsed antioxidant systems that scavenges ROS.
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Affiliation(s)
- Zhong-Lian Yu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China
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23
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Im YJ, Perera IY, Brglez I, Davis AJ, Stevenson-Paulik J, Phillippy BQ, Johannes E, Allen NS, Boss WF. Increasing plasma membrane phosphatidylinositol(4,5)bisphosphate biosynthesis increases phosphoinositide metabolism in Nicotiana tabacum. THE PLANT CELL 2007; 19:1603-16. [PMID: 17496116 PMCID: PMC1913725 DOI: 10.1105/tpc.107.051367] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2007] [Revised: 04/18/2007] [Accepted: 04/23/2007] [Indexed: 05/15/2023]
Abstract
A genetic approach was used to increase phosphatidylinositol(4,5)bisphosphate [PtdIns(4,5)P2] biosynthesis and test the hypothesis that PtdInsP kinase (PIPK) is flux limiting in the plant phosphoinositide (PI) pathway. Expressing human PIPKIalpha in tobacco (Nicotiana tabacum) cells increased plasma membrane PtdIns(4,5)P2 100-fold. In vivo studies revealed that the rate of 32Pi incorporation into whole-cell PtdIns(4,5)P2 increased >12-fold, and the ratio of [3H]PtdInsP2 to [3H]PtdInsP increased 6-fold, but PtdInsP levels did not decrease, indicating that PtdInsP biosynthesis was not limiting. Both [3H]inositol trisphosphate and [3H]inositol hexakisphosphate increased 3-and 1.5-fold, respectively, in the transgenic lines after 18 h of labeling. The inositol(1,4,5)trisphosphate [Ins(1,4,5)P3] binding assay showed that total cellular Ins(1,4,5)P3/g fresh weight was >40-fold higher in transgenic tobacco lines; however, even with this high steady state level of Ins(1,4,5)P3, the pathway was not saturated. Stimulating transgenic cells with hyperosmotic stress led to another 2-fold increase, suggesting that the transgenic cells were in a constant state of PI stimulation. Furthermore, expressing Hs PIPKIalpha increased sugar use and oxygen uptake. Our results demonstrate that PIPK is flux limiting and that this high rate of PI metabolism increased the energy demands in these cells.
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Affiliation(s)
- Yang Ju Im
- Department of Plant Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
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24
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Bargmann BO, Munnik T. The role of phospholipase D in plant stress responses. CURRENT OPINION IN PLANT BIOLOGY 2006; 9:515-22. [PMID: 16877031 DOI: 10.1016/j.pbi.2006.07.011] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Accepted: 07/17/2006] [Indexed: 05/11/2023]
Abstract
Phospholipase D (PLD) has been implicated in multiple plant stress responses. Its gene transcription and activity increase upon exposure to various stresses, and manipulation of PLD protein levels leads to altered stress tolerance. The plant PLD family is relatively large and heterogeneous, and different PLD isoforms are involved in separate stress responses. PLD and its product, phosphatidic acid, exert their effects by functioning in signal transduction cascades and by influencing the biophysical state of lipid membranes.
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Affiliation(s)
- Bastiaan O Bargmann
- Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Kruislaan 318, 1098 SM Amsterdam, The Netherlands
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25
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Lerchner A, Mansfeld J, Schäffner I, Schöps R, Beer HK, Ulbrich-Hofmann R. Two highly homologous phospholipase D isoenzymes from Papaver somniferum L. with different transphosphatidylation potential. Biochim Biophys Acta Mol Cell Biol Lipids 2005; 1737:94-101. [PMID: 16257263 DOI: 10.1016/j.bbalip.2005.09.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Revised: 09/09/2005] [Accepted: 09/21/2005] [Indexed: 11/22/2022]
Abstract
The genes of two phospholipase D (PLD) isoenzymes, PLD1 and PLD2, from poppy seedlings (2829 and 2828 bp) were completely sequenced. The two genes have 96.9% identity in the encoding region and can be assigned to the alpha-type of plant PLDs. The corresponding amino acid sequences do not contain any signal sequences. One Asn-glycosylation site, six and two phosphorylation sites for protein kinase C and tyrosine kinase, respectively, and two phosphatidylinositol-4,5-bisphosphate binding motifs could be identified. Like in most plant PLDs, two HKD motifs and one C2 domain are present. PLD1 and PLD2 have ten and nine cysteine residues. The two enzymes were expressed in E. coli and purified to homogeneity by Ca2+ ion-mediated hydrophobic interaction chromatography. The Ca2+ ion concentration needed for carrier binding of the two enzymes in chromatography as well as for optimum activity was found to be considerably higher (>100 mM) than with other alpha-type plant PLDs. Although PLD1 and PLD2 differ in eleven amino acids only, they showed remarkable differences in their transphosphatidylation activity. Two amino acid exchanges within and near the first HKD motif contribute to this difference as shown by the A349E/E352Q-variant of PLD2.
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Affiliation(s)
- Alexandra Lerchner
- Martin-Luther University Halle-Wittenberg, Department of Biochemistry/Biotechnology, Kurt Mothes Str. 3, D-06120 Halle, Germany
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26
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Ulbrich-Hofmann R, Lerchner A, Oblozinsky M, Bezakova L. Phospholipase D and its application in biocatalysis. Biotechnol Lett 2005; 27:535-44. [PMID: 15973486 DOI: 10.1007/s10529-005-3251-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2005] [Accepted: 02/24/2005] [Indexed: 10/25/2022]
Abstract
Phospholipase D (PLD) from plants or microorganisms is used as biocatalyst in the transformation of phospholipids and phospholipid analogs in both laboratory and industrial scale. In recent years the elucidation of the primary structure of many PLDs from several sources, as well as the resolution of the first crystal structure of a microbial PLD, have yielded new insights into the structural basis and the catalytic mechanism of this catalyst. This review summarizes some new results of PLD research in the light of application.
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Affiliation(s)
- Renate Ulbrich-Hofmann
- Department of Biochemistry/Biotechnology, Martin-Luther University Halle-Wittenberg, D-06120, Halle, Germany.
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27
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Pappan K, Zheng L, Krishnamoorthi R, Wang X. Evidence for and characterization of Ca2+ binding to the catalytic region of Arabidopsis thaliana phospholipase Dbeta. J Biol Chem 2004; 279:47833-9. [PMID: 15356005 DOI: 10.1074/jbc.m402789200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Most types of plant phospholipase D (PLD) require Ca(2+) for activity, but how Ca(2+) affects PLD activity is not well understood. We reported previously that Ca(2+) binds to the regulatory C2 domain that occurs in the N terminus of the Ca(2+)-requiring PLDs. Using Arabidopsis thaliana PLDbeta and C2-deleted PLDbeta (PLDbetacat), we now show that Ca(2+) also interacts with the catalytic regions of PLD. PLDbetacat exhibited Ca(2+)-dependent activity, was much less active, and required a higher level of Ca(2+) than the full-length PLDbeta. Ca(2+) binding of the proteins was stimulated by phospholipids; phosphatidylserine was the most effective among those tested. Scatchard plot analysis of Ca(2+) binding data yielded an estimate of 3.6 high affinity (K(d) = 29 mum) binding sites on PLDbeta. The Ca(2+)-PLDbetacat interaction increased the affinity of the protein for the activator, phosphatidylinositol 4,5-bisphosphate, but not for the substrate, phosphatidylcholine. This is in contrast to the effect of Ca(2+) binding to the C2 domain, which stimulates phosphatidylcholine binding but inhibits phosphatidylinositol 4,5-bisphosphate binding of the domain. These results demonstrate the contrasting and complementary effects of the Ca(2+)- and lipid-binding properties of the C2 and catalytic domains of plant PLD and provide insight into the mechanism by which Ca(2+) regulates PLD activity.
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Affiliation(s)
- Kirk Pappan
- Department of Biochemistry, Kansas State University, Manhattan, Kansas 66506, USA
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28
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Abstract
N-Acylethanolamines (NAEs) are fatty acid amides that are derived from an N-acylated phoshatidylethanolamine presursor, a minor membrane lipid constituent of plant and animal cells. Historically, the formation of N-acylethanolamines was associated with cellular stress and tissue damage in mammals, but more recently has been shown to be part of the endocannabinoid signaling system that regulates a variety of normal physiological functions, including neurotransmission, immune responses, vasodilation, embryo development and implantation, feeding behavior, cell proliferation, etc. The widespread regulation of vertebrate physiology by this class of lipid mediators and the conservation of the mechanisms for NAE formation, perception and degradation in higher plants raises the possibility that the metabolism of NAEs represents an evolutionarily conserved lipid signaling pathway that regulates an array of physiological processes in multicellular eukaryotes. Here the recent information on NAEs in plants is reviewed in the context of the occurrence, metabolism and functions of this bioactive class of lipid mediators.
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Affiliation(s)
- Kent D Chapman
- Center for Plant Lipid Research, Division of Biochemistry and Molecular Biology, Department of Biological Sciences, University of North Texas, P.O. Box 305220, Denton, 76203-5220, USA.
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29
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Zhao J, Wang X. Arabidopsis phospholipase Dalpha1 interacts with the heterotrimeric G-protein alpha-subunit through a motif analogous to the DRY motif in G-protein-coupled receptors. J Biol Chem 2003; 279:1794-800. [PMID: 14594812 DOI: 10.1074/jbc.m309529200] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phospholipase D (PLD) and heterotrimeric G-protein both play important, diverse roles in cellular regulation and signal transduction. Here we have determined the physical interaction between plant PLD and the only canonical alpha-subunit (Galpha) of the G-protein in Arabidopsis thaliana and the molecular basis for the interaction. PLDalpha1 expressed in either Escherichia coli or Arabidopsis was co-precipitated with Galpha. PLDalpha1 contains a sequence motif analogous to the G alpha-interacting DRY motif normally conserved in G-protein-coupled receptors. Mutation of the central Lys residue PLD(K564A) of this motif abolished the PLDalpha1-Galpha binding, whereas mutation of the two flanking residues PLD(E563A) and PLD(F565A) decreased the binding. Addition of Galpha to PLDalpha1 inhibited PLDalpha1 activity, whereas the PLD(K564A) mutation that disrupted the Galpha-PLDalpha1 binding abolished the inhibition. GTP relieved the Galpha inhibition of PLDalpha1 activity and also inhibited the binding between PLDalpha1 and Galpha. Meanwhile, the PLDalpha1-Galpha interaction stimulated the intrinsic GTPase activity of Galpha. Therefore, these results have demonstrated the direct binding between Galpha and PLDalpha1, identified the DRY motif on PLDalpha1 as the site for the interaction, and indicated that the interaction modulates reciprocally the activities of PLDalpha1 and Galpha.
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Affiliation(s)
- Jian Zhao
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
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30
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Potocký M, Eliás M, Profotová B, Novotná Z, Valentová O, Zárský V. Phosphatidic acid produced by phospholipase D is required for tobacco pollen tube growth. PLANTA 2003; 217:122-30. [PMID: 12721856 DOI: 10.1007/s00425-002-0965-4] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2002] [Accepted: 11/26/2002] [Indexed: 05/21/2023]
Abstract
Phospholipase D (PLD) and its product phosphatidic acid (PA) are involved in a number of signalling pathways regulating cell proliferation, membrane vesicle trafficking and defence responses in eukaryotic cells. Here we report that PLD and PA have a role in the process of polarised plant cell expansion as represented by pollen tube growth. Both phosphatidylinositol-4,5-bisphosphate-dependent and independent PLD activities were identified in pollen tube extracts, and activity levels during pollen tube germination and growth were measured. PLD-mediated PA production in vivo can be blocked by primary alcohols, which serve as a substrate for the transphosphatidylation reaction. Both pollen germination and tube growth are stopped in the presence 0.5% 1-butanol, whereas secondary and tertiary isomers do not show any effect. This inhibition could be overcome by addition of exogenous PA-containing liposomes. In the absence of n-butanol, addition of a micromolar concentration of PA specifically stimulates pollen germination and tube elongation. Furthermore, a recently established link between PLD and microtubule dynamics was supported by taxol-mediated partial rescue of the 1-butanol-inhibited pollen tubes. The potential signalling role for PLD-derived PA in plant cell expansion is discussed.
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Affiliation(s)
- Martin Potocký
- Department of Plant Physiology, Faculty of Science, Charles University, Vinicná 5, 128 44, Prague 2, Czech Republic
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31
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Welti R, Li W, Li M, Sang Y, Biesiada H, Zhou HE, Rajashekar CB, Williams TD, Wang X. Profiling membrane lipids in plant stress responses. Role of phospholipase D alpha in freezing-induced lipid changes in Arabidopsis. J Biol Chem 2002; 277:31994-2002. [PMID: 12077151 DOI: 10.1074/jbc.m205375200] [Citation(s) in RCA: 677] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A sensitive approach based on electrospray ionization tandem mass spectrometry has been employed to profile membrane lipid molecular species in Arabidopsis undergoing cold and freezing stresses. Freezing at a sublethal temperature induced a decline in many molecular species of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylglycerol (PG) but induced an increase in phosphatidic acid (PA) and lysophospholipids. To probe the metabolic steps generating these changes, lipids of Arabidopsis deficient in the most abundant phospholipase D, PLD alpha, were analyzed. The PC content dropped only half as much, and PA levels rose only half as high in the PLD alpha-deficient plants as in wild-type plants. In contrast, neither PE nor PG levels decreased significantly more in wild-type plants than in PLD alpha-deficient plants. These data suggest that PC, rather than PE and PG, is the major in vivo substrate of PLD alpha. The action of PLD alpha during freezing is of special interest because Arabidopsis plants that are deficient in PLD alpha have improved tolerance to freezing. The greater loss of PC and increase in PA in wild-type plants as compared with PLD alpha-deficient plants may be responsible for destabilizing membrane bilayer structure, resulting in a greater propensity toward membrane fusion and cell death in wild-type plants.
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Affiliation(s)
- Ruth Welti
- Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66506, USA.
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32
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de Torres Zabela M, Fernandez-Delmond I, Niittyla T, Sanchez P, Grant M. Differential expression of genes encoding Arabidopsis phospholipases after challenge with virulent or avirulent Pseudomonas isolates. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2002; 15:808-16. [PMID: 12182338 DOI: 10.1094/mpmi.2002.15.8.808] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Phospholipase D (PLD; EC 3.1.4.4) has been linked to a number of cellular processes, including Tran membrane signaling and membrane degradation. Four PLD genes (alpha, beta, gamma1, and gamma2) have been cloned from Arabidopsis thalami. They encode isoforms with distinct regulatory and catalytic properties but little is known about their physiological roles. Using cDNA amplified fragment length polymorphism display and RNA blot analysis, we identified Arabidopsis PLDgamma1 and a gene encoding a lysophospholipase (EC 3.1.1.5), lysoPL1, to be differentially expressed during host response to virulent and avirulent pathogen challenge. Examination of the expression pattern of phospholipase genes induced in response to pathogen challenge was undertaken using the lysoPL1 and gene-specific probes corresponding to the PLD isoforms a, beta, and gamma1. Each mRNA class exhibited different temporal patterns of expression after infiltration of leaves with Pseudomonas syringae pv. tomato with or without avrRpm1. PLDalpha was rapidly induced and remained constitutively elevated regardless of treatment. PLDbeta was transiently induced upon pathogen challenge. However, mRNA for the lysoPL1 and PLDgamma1 genes showed enhanced and sustained elevation during an incompatible interaction, in both ndr1 and overexpressing NahG genetic backgrounds. Further evidence for differential engagement of these PLD mRNA during defense responses, other than gene-for-gene interactions, was demonstrated by their response to salicylic acid treatment or wounding. Our results indicate that genes encoding lysoPL1, PLDgamma1, and PLDbeta are induced during early responses to pathogen challenge and, additionally, PLDyl and lysoPL1 are specifically upregulated during gene-for-gene interactions, leading to the hypersensitive response. We discuss the possible role of these genes in plant-pathogen interactions.
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Meijer HJG, ter Riet B, van Himbergen JAJ, Musgrave A, Munnik T. KCl activates phospholipase D at two different concentration ranges: distinguishing between hyperosmotic stress and membrane depolarization. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2002; 31:51-9. [PMID: 12100482 DOI: 10.1046/j.1365-313x.2002.01336.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Hyperosmotic stress induces the rapid formation of phosphatidic acid (PA) in Chlamydomonas moewusii via the activation of two signalling pathways: phospholipase D (PLD) and phospholipase C (PLC), the latter in combination with diacylglycerol kinase (DGK) (Munnik et al., 2000). A concomitant increase in cell Ca(2+) becomes manifest as deflagellation. When KCl was used as osmoticum we found that two concentration ranges activated deflagellation: one between 50 and 100 mm and another above 200 mm. Deflagellation in low KCl concentrations was complete within 30 sec whereas in high concentrations it took 5 min. PLC was not activated, as it was by high KCl concentrations that cause hyperosmotic stress. Moreover PLD was activated more strongly by low than by high KCl concentrations. Potassium was the most potent monovalent cation based on the induction of deflagellation and the formation of PA and PBut. During treatment, the external medium acidified, indicating an increase in H(+)-ATPase activity in order to re-establish the membrane potential. Activation of PLD and deflagellation at low KCl concentrations were abrogated by treatment with La(3+), Gd(3+) and EGTA, indicating the dependency on extracellular Ca(2+). This suggests that low concentrations of KCl depolarize the plasma membrane, resulting in the activation of H(+)-ATPases and opening voltage-dependent Ca(2+) +/- channels, observed as deflagellation and an increase in PLD activity.
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Affiliation(s)
- Harold J G Meijer
- Swammerdam Institute for Life Sciences, Department of Plant Physiology, University of Amsterdam, Kruislaan 318, NL-1098 SM Amsterdam, The Netherlands
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34
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Wang X, Wang C, Sang Y, Qin C, Welti R. Networking of phospholipases in plant signal transduction. PHYSIOLOGIA PLANTARUM 2002; 115:331-335. [PMID: 12081524 DOI: 10.1034/j.1399-3054.2002.1150301.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Phospholipases are activated in response to various cellular and environmental cues. Their activation can affect many cellular processes through their roles in signal transduction. Recent advances in the biochemical and molecular understanding of phospholipase D (PLD) have provided insights into potential networks of PLDs and other phospholipases in plants. PLDs are a family of heterogeneous enzymes, and the activities of the multiple types of PLDs are regulated in distinctly different manners. Phosphoinositides, free fatty acids, lysophospholipids, and calcium are differential modulators of PLDs. Since these modulators are substrates, products, or downstream targets of phospholipase As and phospholipase Cs, there are many potential regulatory and metabolic interrelationships among the various PLDs and other phospholipases.
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Affiliation(s)
- Xuemin Wang
- Department of Biochemistry, Division of Biology, Kansas State University, Manhattan, KS 66506, USA
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35
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The Arabidopsis Phospholipase D Family. Characterization of a
Calcium-Independent and Phosphatidylcholine-Selective PLDζ1 with
Distinct Regulatory Domains 1. PLANT PHYSIOLOGY 2002; 128:1200-11. [PMID: 11891260 PMCID: PMC152217 DOI: 10.1104/pp.010928] [Citation(s) in RCA: 240] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Four types of phospholipase D (PLD), PLDα, β, γ, and δ,
have been characterized in Arabidopsis, and they display different
requirements for Ca2+, phosphatidylinositol
4,5-bisphosphate (PIP2), substrate vesicle composition,
and/or free fatty acids. However, all previously cloned plant PLDs
contain a Ca2+-dependent phospholipid-binding C2 domain and
require Ca2+ for activity. This study documents a new type
of PLD, PLDζ1, which is distinctively different from previously
characterized PLDs. It contains at the N terminus a Phox homology
domain and a pleckstrin homology domain, but not the C2 domain. A
full-length cDNA for Arabidopsis PLDζ1 has been identified and used
to express catalytically active PLD in Escherichia coli.
PLDζ1 does not require Ca2+ or any other divalent cation
for activity. In addition, it selectively hydrolyzes
phosphatidylcholine, whereas the other Arabidopsis PLDs use several
phospholipids as substrates. PLDζ1 requires PIP2 for
activity, but unlike the PIP2-requiring PLDβ or γ,
phosphatidylethanolamine is not needed in substrate vesicles. These
differences are described, together with a genomic analysis of 12
putative Arabidopsis PLD genes that are grouped into α, β, δ,
γ, and ζ based on their gene architectures, sequence similarities,
domain structures, and biochemical properties.
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36
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Eliáš M, Potocký M, Cvrčková F, Žárský V. Molecular diversity of phospholipase D in angiosperms. BMC Genomics 2002; 3:2. [PMID: 11876823 PMCID: PMC77410 DOI: 10.1186/1471-2164-3-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2001] [Accepted: 02/01/2002] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The phospholipase D (PLD) family has been identified in plants by recent molecular studies, fostered by the emerging importance of plant PLDs in stress physiology and signal transduction. However, the presence of multiple isoforms limits the power of conventional biochemical and pharmacological approaches, and calls for a wider application of genetic methodology. RESULTS Taking advantage of sequence data available in public databases, we attempted to provide a prerequisite for such an approach. We made a complete inventory of the Arabidopsis thaliana PLD family, which was found to comprise 12 distinct genes. The current nomenclature of Arabidopsis PLDs was refined and expanded to include five newly described genes. To assess the degree of plant PLD diversity beyond Arabidopsis we explored data from rice (including the genome draft by Monsanto) as well as cDNA and EST sequences from several other plants. Our analysis revealed two major PLD subfamilies in plants. The first, designated C2-PLD, is characterised by presence of the C2 domain and comprises previously known plant PLDs as well as new isoforms with possibly unusual features catalytically inactive or independent on Ca2+. The second subfamily (denoted PXPH-PLD) is novel in plants but is related to animal and fungal enzymes possessing the PX and PH domains. CONCLUSIONS The evolutionary dynamics, and inter-specific diversity, of plant PLDs inferred from our phylogenetic analysis, call for more plant species to be employed in PLD research. This will enable us to obtain generally valid conclusions.
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Affiliation(s)
- Marek Eliáš
- Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, Prague 2, Czech Republic
| | - Martin Potocký
- Department of Biochemistry and Microbiology, Institute of Chemical Technology, Technická 5, Prague 6, Czech Republic
| | - Fatima Cvrčková
- Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, Prague 2, Czech Republic
| | - Viktor Žárský
- Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, Prague 2, Czech Republic
- Institute of Experimental Botany, The Academy of Sciences of the Czech Republic, Rozvojová 135, Prague 6, Czech Republic
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Schäffner I, Rücknagel KP, Mansfeld J, Ulbrich-Hofmann R. Genomic structure, cloning and expression of two phospholipase D isoenzymes from white cabbage. EUR J LIPID SCI TECH 2002. [DOI: 10.1002/1438-9312(200202)104:2<79::aid-ejlt79>3.0.co;2-c] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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38
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Sang Y, Zheng S, Li W, Huang B, Wang X. Regulation of plant water loss by manipulating the expression of phospholipase Dalpha. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2001; 28:135-44. [PMID: 11722757 DOI: 10.1046/j.1365-313x.2001.01138.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Phospholipase D (PLD) has been implicated in various processes, including signal transduction, membrane trafficking, and membrane degradation. Multiple forms of PLD with distinct biochemical properties have been described in the cell. In Arabidopsis, PLDalpha and PLDgamma, but not PLDbeta, were detected in guard cells, and antisense suppression resulted in a specific loss of PLDalpha. The abrogation of PLDalpha rendered plants less sensitive to abscisic acid and impaired stomatal closure induced by water deficits. PLDalpha-depleted plants exhibited accelerated transpirational water loss and a decreased ability to tolerate drought stress. Overexpression of PLDalpha enhanced the leaf's sensitivity to abscisic acid. These findings provide molecular and physiological evidence that PLDalpha plays a crucial role in regulating stomatal movement and plant-water status.
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Affiliation(s)
- Y Sang
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
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Sang Y, Cui D, Wang X. Phospholipase D and phosphatidic acid-mediated generation of superoxide in Arabidopsis. PLANT PHYSIOLOGY 2001; 126:1449-58. [PMID: 11500544 PMCID: PMC117145 DOI: 10.1104/pp.126.4.1449] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Phospholipase D (PLD), which hydrolyzes phospholipids into free head groups and phosphatidic acid (PA), may regulate cellular processes through the production of lipid and lipid-derived messengers. We have genetically abrogated PLD alpha, the most prevalent isoform of PLD in plants, and the depletion of PLD alpha in Arabidopsis decreased the levels of PA and superoxide production in Arabidopsis leaf extracts. Addition of PA promoted the synthesis of superoxide in the PLD alpha-depleted plants, as measured by chemiluminescence and superoxide dismutase-inhibitable, NADPH-dependent reduction of cytochrome c and nitroblue tetrazolium. The PA-enhanced generation of superoxide was associated mainly with microsomal membranes. Among various lipids tested, PA was the most effective stimulator with the optimal concentrations between 100 and 200 microM. The PA-promoted production of superoxide was observed also in leaves directly infiltrated with PA. The added PA was more effective in stimulating superoxide generation in the PLD alpha-depleted leaves than in the PLD alpha-containing, wild-type leaves, suggesting that PA produced in the cell was more effective than added PA in promoting superoxide production. These data indicate that PLD plays a role in mediating superoxide production in plants through the generation of PA as a lipid messenger.
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Affiliation(s)
- Y Sang
- Department of Biochemistry, Kansas State University, Manhattan, Kansas 66506, USA
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40
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Abstract
Phospholipases are a diverse series of enzymes that hydrolyze phospholipids. Multiple forms of phospholipases D, C, and A have been characterized in plants. These enzymes are involved in a broad range of functions in cellular regulation, lipid metabolism, and membrane remodeling. In recent years, increasing attention has been paid to the many roles of phospholipases in signal transduction. This review highlights recent developments in the understanding of biochemical, molecular biological, and functional aspects of various phospholipases in plants.
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Affiliation(s)
- Xuemin Wang
- Department of Biochemistry, Kansas State University, Willard Hall, Manhattan, Kansas 66506; e-mail:
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Sharma S, Gupta MN. Purification of phospholipase D from Dacus carota by three-phase partitioning and its characterization. Protein Expr Purif 2001; 21:310-6. [PMID: 11237693 DOI: 10.1006/prep.2000.1357] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipase D from Dacus carota (carrot) was purified by subjecting it to three-phase partitioning. The single step of three phase partitioning led to 13-fold purification with an activity recovery of 72%. SDS-PAGE analysis showed a single band with minimum molecular weight corresponding to nearly 60 kDa. The purified enzyme had a pH optimum in the range of 6.0--6.5 and was unstable above 30 degrees C. Kinetic studies showed a K(m) value of 9.5 mM and a V(max) of 0.35 mL min(-1). The enzyme purified by three-phase partitioning was found to resolve into two isoenzymes on a DEAE-cellulose column.
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Affiliation(s)
- S Sharma
- Chemistry Department, Indian Institute of Technology, Hauz Khas, New Delhi 110 016, India
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Lein W, Saalbach G. Cloning and direct G-protein regulation of phospholipase D from tobacco. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1530:172-83. [PMID: 11239820 DOI: 10.1016/s1388-1981(00)00182-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phospholipase D (PLD) and heterotrimeric G-proteins are involved in plant signal transduction pathways at the plasma membrane. There is evidence suggesting that PLD acts downstream from G-proteins, but a direct interaction of specific members has not been shown. In the present paper, a PLD cDNA clone was isolated from tobacco, expressed as a GST fusion in bacteria, and the recombinant protein was purified by glutathione affinity. Its enzymatic properties identified it as an alpha-type PLD. The alpha-subunit of a G-protein from tobacco was isolated in a similar way. Both proteins were functional in biochemical assays. When the G-protein was included in the PLD assay, a strong dosage-dependent inhibition of the PLD activity was observed. Different control proteins did not exhibit this inhibitory effect. When GST-NtGPalpha1 was activated by incubation with GTPgammaS the inhibitory activity was greatly reduced. These results provide a first indication for a direct regulation of PLDalpha by a heterotrimeric G-protein alpha-subunit in plants.
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Affiliation(s)
- W Lein
- Institute of Plant Genetics and Crop Plant Research, Corrensstrasse 3, D-06466, Gatersleben, Germany
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43
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Zien CA, Wang C, Wang X, Welti R. In vivo substrates and the contribution of the common phospholipase D, PLDalpha, to wound-induced metabolism of lipids in Arabidopsis. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1530:236-48. [PMID: 11239826 DOI: 10.1016/s1388-1981(01)00091-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The common plant phospholipase D (PLD), PLDalpha, has been proposed to be involved in wound-induced production of jasmonic acid. To better understand the role(s) of PLDalpha in the wound response, detailed lipid analysis was carried out to determine the in vivo substrates and the contribution of PLDalpha in wound-induced lipid metabolism in Arabidopsis thaliana. Mechanical wounding of Arabidopsis leaves resulted in significantly less hydrolysis of phosphatidylcholine (PC) in PLDalpha-deficient than in wild-type plants. Hydrolysis of phosphatidylethanolamine, phosphatidylglycerol (PG), and phosphatidylinositol within 30 min of wounding was not significantly different in PLDalpha-deficient and wild-type leaves. Phosphatidic acid (PA) levels increased rapidly in wild-type and, to a lesser extent, in PLDalpha-deficient plants. The acyl composition of the PA generated by wounding suggests that the major in vivo substrate of PLD in wild-type leaves was PC, and that PG hydrolysis accounted for 10-15% of the wound-induced PA in wild-type leaves. Comparison of the acyl compositions of the wound-induced PA of wild-type and PLDalpha-deficient leaves indicated that PLDalpha hydrolyzed PG more readily than other PLD isoforms did. Wounding produced substantial increases in free linoleic and linolenic acids in wild-type plants, whereas PLDalpha-deficient plants showed only a slight increase in linoleic acid and no significant increase in linolenic acid. These results demonstrate that PLDalpha and at least one other PLD isoform, as well as other hydrolytic enzymes, are active in mechanically wounded Arabidopsis leaves, and PLDalpha is involved in wound-induced metabolism of polyunsaturated fatty acids.
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Affiliation(s)
- C A Zien
- Division of Biology, Kansas State University, Manhattan, KS 66506-4901, USA
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Chapman KD. Emerging physiological roles for N-acylphosphatidylethanolamine metabolism in plants: signal transduction and membrane protection. Chem Phys Lipids 2000; 108:221-9. [PMID: 11106793 DOI: 10.1016/s0009-3084(00)00198-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The activation of N-acylphosphatidylethanolamine (NAPE) metabolism in plants appears to be associated mostly with cellular stresses. In response to pathogen elicitors, NAPE is hydrolzyed by phospholipase-D (PLD), and corresponding medium-chain, saturated N-acylethanolamines (NAEs) are released by plant cells where they act as lipid mediators to modulate ion flux and activate defense gene expression. In desiccated seeds of higher plants, long-chain, saturated and unsaturated NAEs are prevalent, but are rapidly metabolized during the first few hours of imbibition, a period of substantial osmotic stress. NAPE synthesis is increased in seeds during this same period of rapid rehydration. A membrane-bound enzyme designated NAPE synthase has been purified from imbibed cottonseeds and its unusual biochemical properties suggest that it may scavenge free fatty acids in vivo. This feature of NAPE metabolism may be unique to higher plants a may be a mechanism for the rapid recycling of fatty acids back into membrane-associated NAPE. Altogether, increasing evidence indicates that NAPE metabolism in plants shares functional similarities with NAPE metabolism in animal systems, including signal transduction and cellular protection. In particular, the emerging role of released NAEs as lipid mediators in plant defense signaling represents an intriguing parallel to 'endocannabinoid signaling' in several mammalian cell types.
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Affiliation(s)
- K D Chapman
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203-5220, USA.
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Wang X. Multiple forms of phospholipase D in plants: the gene family, catalytic and regulatory properties, and cellular functions. Prog Lipid Res 2000; 39:109-49. [PMID: 10775762 DOI: 10.1016/s0163-7827(00)00002-3] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Multiple Phospholipase D (PLD) genes have been identified in plants and encode isoforms with distinct regulatory and catalytic properties. Elucidation of the genetic and biochemical heterogeneity has provided important clues as to the regulation and function of this family of enzymes. Polyphosphoinositides, Ca(2+), and G-proteins are possible cellular regulators for PLD activation. PLD-mediated hydrolysis of membrane lipids increases in response to various stresses. Recent studies suggest that PLD plays a role in the signaling and production of hormones involved in plant stress responses.
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Affiliation(s)
- X Wang
- Department of Biochemistry, Kansas State University, Manhattan 66506, USA.
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