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The Journal of Biological Chemistry Oct 2014Defining how leukocytes adhere to solid surfaces, such as capillary beds, and the subsequent migration through the extracellular matrix, is a central biological issue....
Defining how leukocytes adhere to solid surfaces, such as capillary beds, and the subsequent migration through the extracellular matrix, is a central biological issue. We show here that phospholipase D (PLD) and its enzymatic reaction product, phosphatidic acid (PA), regulate cell adhesion of immune cells (macrophages and neutrophils) to collagen and have defined the underlying molecular mechanism in a spatio-temporal manner that coincides with PLD activity timing. A rapid (t½ = 4 min) and transient activation of the PLD1 isoform occurs upon adhesion, and a slower (t½ = 7.5 min) but prolonged (>30 min) activation occurs for PLD2. Importantly, PA directly binds to actin-related protein 3 (Arp3) at EC50 = 22 nm, whereas control phosphatidylcholine did not bind. PA-activated Arp3 hastens actin nucleation with a kinetics of t½ = 3 min at 300 nm (compared with controls of no PA, t½ = 5 min). Thus, PLD and PA are intrinsic components of cell adhesion, which reinforce each other in a positive feedback loop and react from cues from their respective solid substrates. In nascent adhesion, PLD1 is key, whereas a sustained adhesion in mature or established focal points is dependent upon PLD2, PA, and Arp3. A prolonged adhesion could effectively counteract the reversible intrinsic nature of this cellular process and constitute a key player in chronic inflammation.
Topics: Actins; Animals; Cell Adhesion; Cell Line; Green Fluorescent Proteins; Inflammation; Lipids; Macrophages; Mice; Neutrophils; Phosphatidic Acids; Phosphatidylcholines; Phospholipase D; Protein Binding; Signal Transduction; Transfection
PubMed: 25187519
DOI: 10.1074/jbc.M114.597146 -
Biochimica Et Biophysica Acta.... Jun 2021In this study, we developed a method to analyze liposomal binding to a cell membrane receptor using fluorescence-labeled liposomes and demonstrated that scavenger class...
In this study, we developed a method to analyze liposomal binding to a cell membrane receptor using fluorescence-labeled liposomes and demonstrated that scavenger class B type 1 (SR-B1) plays a crucial role in binding of liposomes containing phosphatidylcholine (PC) to HEK293T cell membrane and phosphatidic acid (PA) can modulate it. Site-directed mutagenesis of SR-B1 revealed that S112F and T175A mutations in its ectodomain abrogated binding and endocytosis of PC liposomes in HEK293T cells. K151A and K156A mutations attenuated their binding and endocytosis too. Although the effects of mutations on binding and endocytosis were similar between PC liposomes and PC/PA and PA liposomes, SR-B1 dependency appeared to be PC > PC/PA > PA liposomes. Our data indicate that (i) nanoparticles including high-density lipoprotein (HDL), silica, and liposomes bind to a common or close site of SR-B1, and (ii) PC/PA and PA liposomes bind not only to SR-B1 but also other receptor(s) in HEK293T cells. In addition, PC/PA liposomes induced lipid droplet (LD) formation in HEK293T cells more than PC liposomes. Treatment of HEK293T cells with SR-B1 siRNA suppressed PC/PA liposome-induced LD formation. Taken together, our results demonstrate that SR-B1 plays an essential role in binding PC-containing liposomes and the subsequent induction of cellular responses, while PA can modulate them.
Topics: Biophysical Phenomena; HEK293 Cells; Humans; Liposomes; Phosphatidic Acids; Phosphatidylcholines; Protein Binding; Receptors, Scavenger; Scavenger Receptors, Class B
PubMed: 33862056
DOI: 10.1016/j.bbamcr.2021.119043 -
Journal of Chromatography. B,... Feb 2018Cyclic phosphatidic acid (cPA), an analog of lysophosphatidic acid, is involved in the regulation of many cellular processes. A sensitive and specific method to quantify...
Cyclic phosphatidic acid (cPA), an analog of lysophosphatidic acid, is involved in the regulation of many cellular processes. A sensitive and specific method to quantify the molecular species of cPA is important for studying the physiological and pathophysiological roles of cPA. Here, we developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based quantification method for the simultaneous detection of cPA species having various fatty acids (16:0, 18:0, 18:1, and 18:2) as well as 2-carba-cPA, a chemically synthesized analog of cPA. Chromatography was performed using a reversed-phase C18 column. cPA species were detected using a triple quadrupole mass spectrometer. cPA 17:0 was used as an internal standard. Intra- and interday precision values (CV%) were within 10%. The linear range of detection for each cPA species was 0.01 μg/mL to 5 μg/mL, with correlation coefficients of 0.998 or higher. The developed method was applied to the quantification of cPA species in mouse plasma and organs. The concentrations of cPA 16:0, 18:0, and 18:1 were revealed to be significantly reduced in the brains of cuprizone-treated mice, a model of multiple sclerosis, compared with control mice. These findings could be important for understanding the roles of cPA in the neurodegenerative processes associated with multiple sclerosis.
Topics: Animals; Chromatography, Liquid; Cuprizone; Heterocyclic Compounds, 1-Ring; Limit of Detection; Linear Models; Male; Mice; Multiple Sclerosis; Organ Specificity; Phosphatidic Acids; Reproducibility of Results; Tandem Mass Spectrometry
PubMed: 29353671
DOI: 10.1016/j.jchromb.2018.01.002 -
Biochimica Et Biophysica Acta Sep 2016We have examined the lipids of three isolates, Romboutsia lituseburensis, Romboutsia ilealis, and Romboutsia sp. strain FRIFI, of the newly described genus Romboutsia by...
We have examined the lipids of three isolates, Romboutsia lituseburensis, Romboutsia ilealis, and Romboutsia sp. strain FRIFI, of the newly described genus Romboutsia by two-dimensional thin-layer chromatography (2D-TLC) and by liquid chromatography/mass spectrometry (LC/MS). We have found three phospholipids, phosphatidylglycerol (PG), cardiolipin and phosphatidic acid in all three species. A fourth phospholipid, lysyl-PG, was found in R. lituseburensis and strain FRIFI. Polyprenyl-phosphates were identified in the lipid extracts of all three species. Three glycolipids, mono-, di- and tri-hexosyldiacylglycerol, were common to all three species. An additional glycolipid, tetrahexosyl-diacylglycerol was identified in strain FRIFI. Acylated trihexosyldiacylglycerol and acyl-tetrahexosydiacylglycerol were also found in R. ilealis and strain FRIFI. Remarkably, no alk-1-enyl ether lipids (plasmalogens) were present in Romboutsia as distinct from bacteria of the related genus Clostridium in which these ether lipids are common. We have compared the lipidome of Romboutsia with that recently described for Clostridium difficile, which has plasmalogens, no lysyl-PG, and no tetrahexosyl-diacylglycerol. According to 16S rRNA gene sequencing, Romboutsia spp. and C. difficile are closely related (>95% sequence identity).
Topics: Cardiolipins; Chromatography, Liquid; Clostridium; Fatty Acids; Lipids; Mass Spectrometry; Phosphatidic Acids; Phosphatidylglycerols; Phospholipids; RNA, Ribosomal, 16S
PubMed: 27317428
DOI: 10.1016/j.bbalip.2016.06.006 -
Biochimica Et Biophysica Acta Sep 2009Regulated production and elimination of the signaling lipids phosphatidic acid (PA), diacylglycerol (DAG), and phosphatidylinositol 4,5-bisphosphate (PI4,5P(2)) creates... (Review)
Review
Regulated production and elimination of the signaling lipids phosphatidic acid (PA), diacylglycerol (DAG), and phosphatidylinositol 4,5-bisphosphate (PI4,5P(2)) creates a complex and interconnected signaling network that modulates a wide variety of eukaryotic cell biological events. PA production at the plasma membrane and on trafficking membrane organelles by classical Phospholipase D (PLD) through the hydrolysis of phosphatidylcholine (PC) has been studied widely. In this chapter, we review a newly identified, non-canonical member of the PLD superfamily, MitoPLD, which localizes to the mitochondrial surface and plays a role in mitochondrial fusion via the hydrolysis of cardiolipin (CL) to generate PA. The role of PA in facilitating the mitochondrial fusion event carried out by proteins known as Mitofusins is intriguing in light of the role classic PLD-generated PA plays in facilitating SNARE-mediated fusion of secretory membrane vesicles into the plasma membrane. In addition, however, PA on the mitochondrial surface may also trigger a signaling cascade that elevates DAG, leading to downstream events that affect mitochondrial fission and energy production. PA production on the mitochondrial surface may also stimulate local production of PI4,5P(2) to facilitate mitochondrial fission and subcellular trafficking or facilitate Ca(2+) influx.
Topics: Animals; Humans; Lipid Metabolism; Mitochondria; Mitochondrial Membranes; Phosphatidic Acids; Signal Transduction
PubMed: 19540356
DOI: 10.1016/j.bbalip.2009.05.012 -
IUBMB Life Aug 2006Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the predominant membrane phospholipid, phosphatidylcholine producing phosphatidic acid and free choline. This... (Review)
Review
Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the predominant membrane phospholipid, phosphatidylcholine producing phosphatidic acid and free choline. This activity can participate in signal transduction pathways and impact on vesicle trafficking for secretion and endocytosis, as well as receptor signalling. Phospholipids can regulate PLD activity directly, through specific intermolecular interactions, or indirectly, through their effect on the localization or activity of PLD's protein effectors. This short review highlights these various phospholipid inputs into the regulation of PLD activity and also reviews potential roles for PLD-generated phosphatidic acid, particularly a mechanism by which the phospholipid may participate in the process of vesicular trafficking.
Topics: ADP-Ribosylation Factors; Amino Acid Motifs; Amino Acid Sequence; Animals; Biological Transport; Cell Membrane; Humans; Lipid Metabolism; Models, Biological; Phosphatidic Acids; Phospholipase D; Phospholipids; Protein Kinase C; Protein Structure, Tertiary; Signal Transduction; rho GTP-Binding Proteins
PubMed: 16916782
DOI: 10.1080/15216540600871142 -
Plant Signaling & Behavior Jun 2017ARTICLE ADDENDUM Efficient activation and deactivation of Gα protein is critical for the regulation of heterotrimeric G-protein mediated signaling pathways. While the... (Review)
Review
ARTICLE ADDENDUM Efficient activation and deactivation of Gα protein is critical for the regulation of heterotrimeric G-protein mediated signaling pathways. While the core G-protein components and their activation/deactivation chemistries are broadly conserved throughout the eukaryotic evolution, their regulatory mechanisms seem to have been rewired in plants to meet specific needs. Plants such as Arabidopsis, which have a limited number of G-protein components and their regulators, offer a unique opportunity to dissect the mechanistic details of distinct signaling pathways. We have recently established an interaction between the regulator of G-protein signaling 1 (RGS1) and phospholipase Dα1 (PLDα1); 2 of the GTPase activity accelerating proteins (GAPs) of the Arabidopsis Gα protein, GPA1. We now show that phosphatidic acid (PA), a key product of PLDα1 activity, can bind with and modulate the GAP activity of RGS1, uncovering a molecular link between lipid and G-protein signaling and its role in providing the specificity of response regulation.
Topics: Heterotrimeric GTP-Binding Proteins; Models, Biological; Phosphatidic Acids; Plant Proteins; Plants; Signal Transduction
PubMed: 28532301
DOI: 10.1080/15592324.2017.1325983 -
European Journal of Biochemistry Nov 1999Phosphatidic acid (PtdOH) is a key intermediate in glycerolipid biosynthesis. Two different pathways are known for de novo formation of this compound, namely (a) the... (Review)
Review
Phosphatidic acid (PtdOH) is a key intermediate in glycerolipid biosynthesis. Two different pathways are known for de novo formation of this compound, namely (a) the Gro3P (glycerol 3-phosphate) pathway, and (b) the GrnP (dihydroxyacetone phosphate) pathway. Whereas the former route of PtdOH synthesis is present in bacteria and all types of eukaryotes, the GrnP pathway is restricted to yeast and mammalian cells. In this review article, we describe the enzymes catalyzing de novo formation of PtdOH, their properties and their occurrence in different cell types and organelles. Much attention has recently been paid to the subcellular localization of enzymes involved in the biosynthesis of PtdOH. In all eukaryotic cells, microsomes (ER) harbour the complete set of enzymes catalyzing these pathways and are thus the usual organelle for PtdOH formation. In contrast, the contribution of mitochondria to PtdOH synthesis is restricted to certain enzymes and depends on the cell type. In addition, chloroplasts of plants, lipid particles of the yeast, and peroxisomes of mammalian cells are significantly involved in PtdOH biosynthesis. Redundant systems of acyltransferases, the interplay of organelles, regulation of the pathway on the compartmental level, and finally the contribution of alternative pathways (phosphorylation of diacylglycerol and cleavage of phospholipids by phospholipases) to PtdOH biosynthesis appear to be required for the balanced formation of this important lipid intermediate. Dysfunction of enzymes involved in PtdOH synthesis can result in severe defects of various cellular processes. In this context, the possible physiological role(s) of PtdOH and its related metabolites, lysophosphatidic acid and diacylglycerol, will be discussed.
Topics: Acyltransferases; Animals; Dihydroxyacetone Phosphate; Glycerophosphates; Lipid Metabolism; Lysophospholipids; Mammals; Microsomes; Organelles; Phenotype; Phosphatidic Acids; Prokaryotic Cells
PubMed: 10542045
DOI: 10.1046/j.1432-1327.1999.00822.x -
Journal of Lipid Research Apr 2022Second messengers are small rapidly diffusing molecules or ions that relay signals between receptors and effector proteins to produce a physiological effect. Lipid... (Review)
Review
Second messengers are small rapidly diffusing molecules or ions that relay signals between receptors and effector proteins to produce a physiological effect. Lipid messengers constitute one of the four major classes of second messengers. The hydrolysis of two main classes of lipids, glycerophospholipids and sphingolipids, generate parallel profiles of lipid second messengers: phosphatidic acid (PA), diacylglycerol (DAG), and lysophosphatidic acid versus ceramide, ceramide-1-phosphate, sphingosine, and sphingosine-1-phosphate, respectively. In this review, we examine the mechanisms by which these lipid second messengers modulate aldosterone production at multiple levels. Aldosterone is a mineralocorticoid hormone responsible for maintaining fluid volume, electrolyte balance, and blood pressure homeostasis. Primary aldosteronism is a frequent endocrine cause of secondary hypertension. A thorough understanding of the signaling events regulating aldosterone biosynthesis may lead to the identification of novel therapeutic targets. The cumulative evidence in this literature emphasizes the critical roles of PA, DAG, and sphingolipid metabolites in aldosterone synthesis and secretion. However, it also highlights the gaps in our knowledge, such as the preference for phospholipase D-generated PA or DAG, as well as the need for further investigation to elucidate the precise mechanisms by which these lipid second messengers regulate optimal aldosterone production.
Topics: Aldosterone; Ceramides; Phosphatidic Acids; Phospholipase D; Second Messenger Systems; Sphingolipids
PubMed: 35278411
DOI: 10.1016/j.jlr.2022.100191 -
Journal of Bacteriology Dec 1997Lipid particles of the yeast Saccharomyces cerevisiae harbor two enzymes that stepwise acylate glycerol-3-phosphate to phosphatidic acid, a key intermediate in lipid...
Lipid particles of the yeast Saccharomyces cerevisiae harbor two enzymes that stepwise acylate glycerol-3-phosphate to phosphatidic acid, a key intermediate in lipid biosynthesis. In lipid particles of the s1c1 disruptant YMN5 (M. M. Nagiec et al., J. Biol. Chem. 268:22156-22163, 1993) acylation stops after the first step, resulting in the accumulation of lysophosphatidic acid. Two-dimensional gel electrophoresis confirmed that S1c1p is a component of lipid particles. Lipid particles of a second mutant strain, TTA1 (T. S. Tillman and R. M. Bell, J. Biol. Chem. 261:9144-9149, 1986), which harbors a point mutation in the GAT gene, are essentially devoid of glycerol-3-phosphate acyltransferase activity in vitro. Synthesis of phosphatidic acid is reconstituted by combining lipid particles from YMN5 and TTA1. These results indicate that two distinct enzymes are necessary for phosphatidic acid synthesis in lipid particles: the first step, acylation of glycerol-3-phosphate, is catalyzed by a putative Gat1p; the second step, acylation of lysophosphatidic acid, requires S1c1p. Surprisingly, YMN5 and TTA1 mutants grow like the corresponding wild types because the endoplasmic reticulum of both mutants has the capacity to form a reduced but significant amount of phosphatidic acid. As a consequence, an s1c1 gat1 double mutant is also viable. Lipid particles from this double mutant fail completely to acylate glycerol-3-phosphate, whereas endoplasmic reticulum membranes harbor residual enzyme activities to synthesize phosphatidic acid. Thus, yeast contains at least two independent systems of phosphatidic acid biosynthesis.
Topics: Acyltransferases; Dyneins; Endoplasmic Reticulum; Fatty Acids; Fungal Proteins; Glycerol-3-Phosphate O-Acyltransferase; Mutation; Phosphatidic Acids; Phospholipids; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Subcellular Fractions; Triglycerides
PubMed: 9401016
DOI: 10.1128/jb.179.24.7611-7616.1997