Formation of diacylglycerol by a phospholipase D-phosphatidate phosphatase pathway specific for phosphatidylcholine in endothelial cells

Martin, Thomas W.

doi:10.1016/0005-2760(88)90258-5

Cited by 141 publications

(65 citation statements)

References 51 publications

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“…After incubation at 37°C, samples were proceeded as reported previously (27). Choline present in the reaction was separated from phosphorus-containing choline metabolites as described by T. W. Martin (28).…”

Section: Methodsmentioning

confidence: 99%

Inhibition of Cytosolic Phospholipase A2 by Annexin V in Differentiated Permeabilized HL-60 Cells

Mira

Dubois

Oudinet

et al. 1997

Journal of Biological Chemistry

107

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Annexin V belongs to a family of proteins that interact with phospholipids in a Ca 2؉ -dependent manner. This protein has been demonstrated to have anti-phospholipase A 2 activity. However, this effect has never yet been reported with the 85-kDa cytosolic PLA 2 (cPLA 2 ). We studied, in a model of differentiated and streptolysin O-permeabilized HL-60 cells, the effect of annexin V on cPLA 2 activity after stimulation by calcium, GTP␥S (guanosine 5-O-(3-thiotriphosphate)), formyl-Met-LeuPhe, or phorbol 12-myristate 13-acetate. Both recombinant and human placental purified annexin V inhibit cPLA 2 activity whatever the stimulus used. The decrease of arachidonic acid release is of 40 and 50%, respectively, at [Ca 2؉ ] of 3 and 10 M. The mechanism of inhibition was also analyzed. cPLA 2 requires calcium and protein kinase C (PKC) or mitogen-activated protein kinase phosphorylation for its activation. As annexin V was shown to be an endogenous inhibitor of PKC, PKC-stimulated cPLA 2 activity was analyzed. Using GF109203x, a specific PKC inhibitor, we demonstrated that this pathway is of minor importance in our model. cPLA 2 inhibition by annexin V is not linked to PKC inhibition. To test the hypothesis of phospholipid depletion, mutants of annexin V were constructed using mutagenesis directed to Ca 2؉ site. We demonstrate that the Ca 2؉ site located in domain I is necessary for the inhibitory effect of annexin V on cPLA 2 activity. The site in domain IV is also involved but with less efficiency. In contrast, mutations in site II and III do not modify this effect. Moreover, annexin V mutated on all sites does not inhibit cPLA 2 . Thus, we propose a predominant role of module (I/IV) in the biological action of annexin V, which, in physiological conditions, may control cPLA 2 activity by depletion of the phospholipid substrate.

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Section: Methodsmentioning

confidence: 99%

Inhibition of Cytosolic Phospholipase A2 by Annexin V in Differentiated Permeabilized HL-60 Cells

Mira

Dubois

Oudinet

et al. 1997

Journal of Biological Chemistry

107

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“…The remaining flux of PUFA from PC to TAG may involve PC associated with phospholipase-based production of PC-derived DAG. Widespread evidence for the concerted action of PLD and PAP includes reports in mammalian literature that demonstrate DAG production from endothelialderived PC (Martin, 1988) and endogenous DAG generation in human polymorphonuclear leukocytes where DAG stimulated 5-lipoxygenase enzyme activity and function (Albert et al, 2008). In plants, isolated protein bodies from seedlings show both activities of PLD and PAP (Herman and Chrispeels, 1980), and studies of AtPLD z1 and AtPLD z2 suggest the supply of DAG for galactolipid synthesis is dependent on this pathway and also subverts phosphorus starvation (Cruz-Ramírez et al, 2006;Li et al, 2006).…”

Section: Carbon Flux Between Dag and Pc Are Highly Interconnected In mentioning

confidence: 99%

Phospholipase Dζ Enhances Diacylglycerol Flux into Triacylglycerol

Yang

Wang

et al. 2017

Plant Physiol.

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Plant seeds are the primary source of triacylglycerols (TAG) for food, feed, fuel, and industrial applications. As TAG is produced from diacylglycerol (DAG), successful engineering strategies to enhance TAG levels have focused on the conversion of DAG to TAG. However, the production of TAG can be limited by flux through the enzymatic reactions that supply DAG. In this study, two Arabidopsis phospholipase D z genes (AtPLD z1 and AtPLD z2 ) were coexpressed in Camelina sativa to test whether the conversion of phosphatidylcholine to DAG impacts TAG levels in seeds. The resulting transgenic plants produced 2% to 3% more TAG as a component of total seed biomass and had increased 18:3 and 20:1 fatty acid levels relative to wild type. Increased DAG and decreased PC levels were examined through the kinetics of lipid assembly by [ 14 C]acetate and [ 14 C]glycerol incorporation into glycerolipids. [ 14 C]acetate was rapidly incorporated into TAG in both wild-type and overexpression lines, indicating a significant flux of nascent and elongated acyl-CoAs into the sn-3 position of TAG. Stereochemical analysis revealed that newly synthesized fatty acids were preferentially incorporated into the sn-2 position of PC, but the sn-1 position of de novo DAG and indicated similar rates of nascent acyl groups into the Kennedy pathway and acyl editing. [ 14 C]glycerol studies demonstrated PC-derived DAG is the major source of DAG for TAG synthesis in both tissues. The results emphasize that the interconversions of DAG and PC pools can impact oil production and composition.

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“…Choline was separated from glycerophosphocholine and phosphocholine by cation-exchange chromatography as described [31]. The upper aqueous phase was applied to a l-ml bed volume of Bio-Rex 70 cation-exchange resin (100-200 mesh) in the sodium form.…”

Section: Separation Of Free Choline From Glycerophosphocholine and Phmentioning

confidence: 99%

Rat brain cytosol contains a factor which reconstitutes guanine‐nucleotide‐binding‐protein‐regulated phospholipase‐D activation in HL60 cells previously permeabilized with streptolysin O

Geny

Fensome

Cockcroft

1993

European Journal of Biochemistry

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We report that guanosine 5'-[y-thioltriphosphate (GTP [S]) can stimulate phospholipase D (PLD) in HL60 cells acutely permeabilized with steptolysin 0. The ability of GTP [S] to stimulate PLD is impaired if the cells are previously permeabilized such that the majority of the cytosol has leaked out. Rat brain and HL60 cytosols were both found to restore GTP[S]-stimulated PLD activity in a reconstitution assay consisting of previously permeabilized HL60 cells. Rat brain cytosol was fractionated on heparin agarose and assayed for reconstitution of GTP[S]-stimulated PLD activity. The active fractions were pooled, concentrated and chromatographed on gel filtration to assess its molecular mass. The molecular mass of the reconstituting factor was found to be 16 kDa. Reconstitution by the cytosolic factor was dependent on GTP [S]. Ca2+ (pCa5), MgATP and MgC1, enhanced GTP[S]-dependent reconstitution of PLD activity in the previously perrneabilized HL60 cells. These results demonstrate the presence in rat brain cytosol of a factor which is an activator of GTP[S]-stimulated PLD.Phosphatidylcholine (PtdCho) is the major phospholipid in mammalian cells. It has long been thought to be a structural lipid but during the last decade, as for the other phospholipids, it has been shown to be hydrolysed in response to extracellular signals. Phospholipases A?, D and, more recently, C, which are known to hydrolyse PtdCho, have been demonstrated to be activated in response to receptor coupling (see reviews [l -31. Both PtdCho-specific phospholipases C and D are important in cell regulation as either directly before or after dephosphorylation of phosphatidic acid (PtdOH), respectively, they will generate a second messenger, diacylglycerol. This molecule has been shown to play an important role in modulating the activity of protein kinase C (see reviews [4, 51). In addition, it has been postulated that PtdOH may be a second messenger [6].In the human promyelocytic cell line, HL-60, the hydrolysis of PtdCho via the activation of phospholipase D (PLD) has been reported by different authors including us ated-activation of PLD by ATP, which binds to P, purinergic receptors, and by the chemotactic factor, formyl-methionylleucyl-phenylalanine, has been demonstrated [11 -131. It has been shown that in HL-60 cells, this enzyme is regulated via protein kinase C [14, 15, 91 and also via a guanine-nucleotide-binding-regulatory (G)-protein [7-9, 12, 161. Moreover our results [9] and those of others [7, 171 indicate that the activation of PLD is dependent on the presence of cytosolic factors.The subcellular localization of PLD in mammalian cells has been reported to be the membranes [18-261. However, this enzyme has also been found in the cytosol [27, 281. As PLD has not been purified to homogeneity, its subcellular localization remains to be resolved, but it is highly possible that the enzyme may be present in the membranes as well as in the cytosol as shown for the phosphoinositol-lipid-specific phospholipases (see review [29]).The present wo...

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Formation of diacylglycerol by a phospholipase D-phosphatidate phosphatase pathway specific for phosphatidylcholine in endothelial cells

Cited by 141 publications

References 51 publications

Inhibition of Cytosolic Phospholipase A2 by Annexin V in Differentiated Permeabilized HL-60 Cells

Inhibition of Cytosolic Phospholipase A2 by Annexin V in Differentiated Permeabilized HL-60 Cells

Phospholipase Dζ Enhances Diacylglycerol Flux into Triacylglycerol

Rat brain cytosol contains a factor which reconstitutes guanine‐nucleotide‐binding‐protein‐regulated phospholipase‐D activation in HL60 cells previously permeabilized with streptolysin O

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