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Biochimica Et Biophysica Acta Jun 2014There are six major species of phospholipids in eukaryotes, each of which plays unique structural and functional roles. One species, phosphatidylinositol (PI) only... (Review)
Review
There are six major species of phospholipids in eukaryotes, each of which plays unique structural and functional roles. One species, phosphatidylinositol (PI) only contributes about 2-10% of the total phospholipid pool. However, they are critical factors in the regulation of several fundamental processes such as in membrane dynamics and signal transduction pathways. Although numerous acyl species exist, PI species are enriched with one specific acyl chain composition at both sn-1 and sn-2 positions. Recent work has identified several enzymes that act on lipids to lead to the formation or interconversion of PI species that exhibit acyl chain specificity. These enzymes contribute to this lipid's enrichment with specific acyl chains. The nature of the acyl chains on signaling lipids has been shown to contribute to their specificity. Here we review some of the critical functions of PI and the multiple pathways in which PI can be produced and metabolized. We also discuss a common motif that may confer arachidonoyl specificity to several of the enzymes involved. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
Topics: Acylation; Animals; Arachidonic Acid; Cell Membrane; Humans; Phosphatidylinositols
PubMed: 24120446
DOI: 10.1016/j.bbamem.2013.10.003 -
Chemistry and Physics of Lipids Jul 2019Aerobic life is based on numerous metabolic oxidation reactions as well as biosynthesis of oxygenated signaling compounds. Among the latter are the myriads of oxygenated... (Review)
Review
Aerobic life is based on numerous metabolic oxidation reactions as well as biosynthesis of oxygenated signaling compounds. Among the latter are the myriads of oxygenated lipids including a well-studied group of polyunsaturated fatty acids (PUFA) - octadecanoids, eicosanoids, and docosanoids. During the last two decades, remarkable progress in liquid-chromatography-mass spectrometry has led to significant progress in the characterization of oxygenated PUFA-containing phospholipids, thus designating the emergence of a new field of lipidomics, redox lipidomics. Although non-enzymatic free radical reactions of lipid peroxidation have been mostly associated with the aberrant metabolism typical of acute injury or chronic degenerative processes, newly accumulated evidence suggests that enzymatically catalyzed (phospho)lipid oxygenation reactions are essential mechanisms of many physiological pathways. In this review, we discuss a variety of contemporary protocols applicable for identification and quantitative characterization of different classes of peroxidized (phospho)lipids. We describe applications of different types of LCMS for analysis of peroxidized (phospho)lipids, particularly cardiolipins and phosphatidylethanolalmines, in two important types of programmed cell death - apoptosis and ferroptosis. We discuss the role of peroxidized phosphatidylserines in phagocytotic signaling. We exemplify the participation of peroxidized neutral lipids, particularly tri-acylglycerides, in immuno-suppressive signaling in cancer. We also consider new approaches to exploring the spatial distribution of phospholipids in the context of their oxidizability by MS imaging, including the latest achievements in high resolution imaging techniques. We present innovative approaches to the interpretation of LC-MS data, including audio-representation analysis. Overall, we emphasize the role of redox lipidomics as a communication language, unprecedented in diversity and richness, through the analysis of peroxidized (phospho)lipids.
Topics: Chromatography, Liquid; Humans; Lipidomics; Mass Spectrometry; Oxidation-Reduction; Phospholipids
PubMed: 30928338
DOI: 10.1016/j.chemphyslip.2019.03.012 -
STAR Protocols Dec 2022The plasma membrane containing cholesterol exhibits phospholipid asymmetry, with phosphatidylcholine and sphingomyelin enriched in its outer leaflet and...
The plasma membrane containing cholesterol exhibits phospholipid asymmetry, with phosphatidylcholine and sphingomyelin enriched in its outer leaflet and phosphatidylserine (PtdSer) and phosphatidylethanolamine (PtdEtn) on the cytoplasmic side. We herein describe steps for bacterial expression of recombinant proteins that bind to membrane lipids, followed by affinity purification. Using fluorescence-labeled phospholipid analogs, we further detail the assay to detect flippase activity, which maintains the single-sided distribution of PtdSer and PtdEtn, in mammalian cells. For complete details on the use and execution of this protocol, please refer to Segawa et al. (2021)..
Topics: Animals; Cell Membrane; Phospholipids; Phosphatidylcholines; Biological Transport; Mammals
PubMed: 36595929
DOI: 10.1016/j.xpro.2022.101870 -
Cold Spring Harbor Perspectives in... Oct 2013Intracellular organelles, including endosomes, show differences not only in protein but also in lipid composition. It is becoming clear from the work of many... (Review)
Review
Intracellular organelles, including endosomes, show differences not only in protein but also in lipid composition. It is becoming clear from the work of many laboratories that the mechanisms necessary to achieve such lipid segregation can operate at very different levels, including the membrane biophysical properties, the interactions with other lipids and proteins, and the turnover rates or distribution of metabolic enzymes. In turn, lipids can directly influence the organelle membrane properties by changing biophysical parameters and by recruiting partner effector proteins involved in protein sorting and membrane dynamics. In this review, we will discuss how lipids are sorted in endosomal membranes and how they impact on endosome functions.
Topics: Biological Transport; Cholesterol; Endosomes; Intracellular Membranes; Lipid Metabolism; Membrane Lipids; Models, Biological; Phosphatidylinositols; Phospholipids
PubMed: 24086044
DOI: 10.1101/cshperspect.a016816 -
Biomolecules Feb 2021Phospholipid-modified gold nanorods (phospholipid-GNRs) have demonstrated drastic cytotoxicity towards MCF-7 breast cancer cells compared to polyethylene glycol-coated...
Phospholipid-modified gold nanorods (phospholipid-GNRs) have demonstrated drastic cytotoxicity towards MCF-7 breast cancer cells compared to polyethylene glycol-coated GNRs (PEG-GNRs). In this study, the mechanism of cytotoxicity of phospholipid-GNRs towards MCF-7 cells was investigated using mass spectrometry-based global metabolic profiling and compared to PEGylated counterparts. The results showed that when compared to PEG-GNRs, phospholipid-GNRs induced significant and more pronounced impact on the metabolic profile of MCF-7 cells. Phospholipid-GNRs significantly decreased the levels of metabolic intermediates and end-products associated with cellular energy metabolisms resulting in dysfunction in TCA cycle, a reduction in glycolytic activity, and imbalance of the redox state. Additionally, phospholipid-GNRs disrupted several metabolism pathways essential for the normal growth and proliferation of cancer cells including impairment in purine, pyrimidine, and glutathione metabolisms accompanied by lower amino acid pools. On the other hand, the effects of PEG-GNRs were limited to alteration of glycolysis and pyrimidine metabolism. The current work shed light on the importance of metabolomics as a valuable analytical approach to explore the molecular effects of GNRs with different surface chemistry on cancer cell and highlights metabolic targets that might serve as promising treatment strategy in cancer.
Topics: Cell Death; Chromatography, Liquid; Cluster Analysis; Energy Metabolism; Gold; Humans; MCF-7 Cells; Mass Spectrometry; Metabolic Networks and Pathways; Metabolome; Metabolomics; Multivariate Analysis; Nanotubes; Phospholipids; Polyethylene Glycols
PubMed: 33673519
DOI: 10.3390/biom11030364 -
The Biochemical Journal Oct 19781. The composition and metabolism of phospholipids were studied in various tissues from both normal and dystrophic mice of the 129 ReJ strain. Phospholipids extracted...
1. The composition and metabolism of phospholipids were studied in various tissues from both normal and dystrophic mice of the 129 ReJ strain. Phospholipids extracted from forebrain, spinal cord, sciatic nerve and plasma were fractionated by t.l.c. and measured. 2. Very significant alterations were found in the choline phospholipids from these tissues, except forebrain. Plasma phosphatidylcholine in the dystrophic mouse was increased by 38%. There was a 2-fold increase in lysophosphatidylcholine in the spinal cord of dystrophic mice. The sciatic nerve showed a marked decrease in sphingomyelin content, which is approximately half of that in the controls. 3. Five enzymes involved in phosphatidylcholine metabolism [namely cholinephosphotransferase (EC 2.7.8.2); phospholipases A (EC 3.1.1.4, EC 3.1.1.32); lysophospholipase (EC 3.1.1.5); lysophosphatidylcholine acyltransferase (EC 2.3.1.23); phospholipase C (EC 3.1.4.3)] were studied in tissue preparations from forebrain, spinal cord, sciatic nerves, gastrocnemius muscles and liver. 4. Activities of phospholipases A and C were significantly increased, about 5-fold and 60% respectively, in gastrocnemius muscle of dystrophic mice compared with controls. Phospholipases A also showed 50% higher activity in the sciatic nerves of dystrophic than of normal mice. Lysophosphatidylcholine acyltransferase activities were significantly increased in the sciatic nerves and spinal cord, by 50-100% over that of the controls. The forebrain and spinal cord from dystrophic mice, however, had only 60% of lysophospholipase activities of that of the normal control. Cholinephosphotransferase activity was unchanged in these tissues from both normal and dystrophic mice. 5. It is suggested that are number of features of mouse muscular dystrophy related to altered membrane structure and function can be rationalized in terms of changes in lipid composition and metabolism.
Topics: 1-Acylglycerophosphocholine O-Acyltransferase; Animals; Mice; Muscular Dystrophy, Animal; Nerve Tissue; Phosphatidylcholines; Phospholipases; Phospholipids; Tissue Distribution
PubMed: 728103
DOI: 10.1042/bj1760015 -
The Journal of Cell Biology Feb 2009Mitochondrial membrane biogenesis requires the import and synthesis of proteins as well as phospholipids. How the mitochondrion regulates phospholipid levels and... (Review)
Review
Mitochondrial membrane biogenesis requires the import and synthesis of proteins as well as phospholipids. How the mitochondrion regulates phospholipid levels and maintains a tight protein-to-phospholipid ratio is not well understood. Two recent papers (Kutik, S., M. Rissler, X.L. Guan, B. Guiard, G. Shui, N. Gebert, P.N. Heacock, P. Rehling, W. Dowhan, M.R. Wenk, et al. 2008. J. Cell Biol. 183:1213-1221; Osman, C., M. Haag, C. Potting, J. Rodenfels, P.V. Dip, F.T. Wieland, B. Brügger, B. Westermann, and T. Langer. 2009. J. Cell Biol. 184:583-596) identify novel regulators of mitochondrial phospholipid biosynthesis. The biochemical approach of Kutik et al. (2008) uncovered an unexpected role of the mitochondrial translocator assembly and maintenance protein, Tam41, in the biosynthesis of cardiolipin (CL), the signature phospholipid of mitochondria. The genetic analyses of Osman et al. (2009) led to the discovery of a new class of mitochondrial proteins that coordinately regulate CL and phosphatidylethanolamine, another key mitochondrial phospholipid. These elegant studies highlight overlapping functions and interdependent roles of mitochondrial phospholipid biosynthesis and protein import and assembly.
Topics: Animals; Biosynthetic Pathways; Humans; Mitochondrial Membranes; Mitochondrial Proteins; Phospholipids
PubMed: 19237595
DOI: 10.1083/jcb.200901127 -
Annual Review of Biochemistry 2011The yeast Saccharomyces cerevisiae, with its full complement of organelles, synthesizes membrane phospholipids by pathways that are generally common to those found in... (Review)
Review
The yeast Saccharomyces cerevisiae, with its full complement of organelles, synthesizes membrane phospholipids by pathways that are generally common to those found in higher eukaryotes. Phospholipid synthesis in yeast is regulated in response to a variety of growth conditions (e.g., inositol supplementation, zinc depletion, and growth stage) by a coordination of genetic (e.g., transcriptional activation and repression) and biochemical (e.g., activity modulation and localization) mechanisms. Phosphatidate (PA), whose cellular levels are controlled by the activities of key phospholipid synthesis enzymes, plays a central role in the transcriptional regulation of phospholipid synthesis genes. In addition to the regulation of gene expression, phosphorylation of key phospholipid synthesis catalytic and regulatory proteins controls the metabolism of phospholipid precursors and products.
Topics: Gene Expression Regulation, Fungal; Inositol; Metabolic Networks and Pathways; Molecular Structure; Phospholipids; Phosphorylation; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Zinc
PubMed: 21275641
DOI: 10.1146/annurev-biochem-060409-092229 -
Biochimica Et Biophysica Acta Jul 2014Membrane electropermeabilization relies on the transient permeabilization of the plasma membrane of cells submitted to electric pulses. This method is widely used in...
Membrane electropermeabilization relies on the transient permeabilization of the plasma membrane of cells submitted to electric pulses. This method is widely used in cell biology and medicine due to its efficiency to transfer molecules while limiting loss of cell viability. However, very little is known about the consequences of membrane electropermeabilization at the molecular and cellular levels. Progress in the knowledge of the involved mechanisms is a biophysical challenge. As a transient loss of membrane cohesion is associated with membrane permeabilization, our main objective was to detect and visualize at the single-cell level the incidence of phospholipid scrambling and changes in membrane order. We performed studies using fluorescence microscopy with C6-NBD-PC and FM1-43 to monitor phospholipid scrambling and membrane order of mammalian cells. Millisecond permeabilizing pulses induced membrane disorganization by increasing the translocation of phosphatidylcholines according to an ATP-independent process. The pulses induced the formation of long-lived permeant structures that were present during membrane resealing, but were not associated with phosphatidylcholine internalization. These pulses resulted in a rapid phospholipid flip/flop within less than 1s and were exclusively restricted to the regions of the permeabilized membrane. Under such electrical conditions, phosphatidylserine externalization was not detected. Moreover, this electrically-mediated membrane disorganization was not correlated with loss of cell viability. Our results could support the existence of direct interactions between the movement of membrane zwitterionic phospholipids and the electric field.
Topics: Adenosine Triphosphate; Animals; CHO Cells; Cell Line; Cell Membrane; Cell Membrane Permeability; Cell Survival; Cricetulus; Electroporation; Phosphatidylcholines; Phospholipids
PubMed: 24583083
DOI: 10.1016/j.bbamem.2014.02.013 -
Physiological Reviews Jan 2013Endocytosis, phagocytosis, and macropinocytosis are fundamental processes that enable cells to sample their environment, eliminate pathogens and apoptotic bodies, and... (Review)
Review
Endocytosis, phagocytosis, and macropinocytosis are fundamental processes that enable cells to sample their environment, eliminate pathogens and apoptotic bodies, and regulate the expression of surface components. While a great deal of effort has been devoted over many years to understanding the proteins involved in these processes, the important contribution of phospholipids has only recently been appreciated. This review is an attempt to collate and analyze the rapidly emerging evidence documenting the role of phospholipids in clathrin-mediated endocytosis, phagocytosis, and macropinocytosis. A primer on phospholipid biosynthesis, catabolism, subcellular distribution, and transport is presented initially, for reference, together with general considerations of the effects of phospholipids on membrane curvature and charge. This is followed by a detailed analysis of the critical functions of phospholipids in the internalization processes and in the maturation of the resulting vesicles and vacuoles as they progress along the endo-lysosomal pathway.
Topics: Animals; Biological Transport; Cell Membrane; Clathrin; Endocytosis; Endosomes; Humans; Intracellular Membranes; Lysosomes; Phagocytosis; Phospholipids; Pinocytosis
PubMed: 23303906
DOI: 10.1152/physrev.00002.2012