1
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Laquel P, Ayciriex S, Doignon F, Camougrand N, Fougère L, Rocher C, Wattelet-Boyer V, Bessoule JJ, Testet E. Mlg1, a yeast acyltransferase located in ER membranes associated with mitochondria (MAMs), is involved in de novo synthesis and remodelling of phospholipids. FEBS J 2024; 291:2683-2702. [PMID: 38297966 DOI: 10.1111/febs.17068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 11/27/2023] [Accepted: 01/17/2024] [Indexed: 02/02/2024]
Abstract
In cells, phospholipids contain acyl chains of variable lengths and saturation, features that affect their functions. Their de novo synthesis in the endoplasmic reticulum takes place via the cytidine diphosphate diacylglycerol (CDP-DAG) and Kennedy pathways, which are conserved in eukaryotes. PA is a key intermediate for all phospholipids (PI, PIPs, PS, PE, PC, PG and CL). The de novo synthesis of PA occurs by acylation of glycerophosphate leading to the synthesis of 1-acyl lysoPA and subsequent acylation of 1-acyl lysoPA at the sn-2 position. Using membranes from Escherichia coli overexpressing MLG1, we showed that the yeast gene MLG1 encodes an acyltransferase, leading specifically to the synthesis of PA from 1-acyl lysoPA. Moreover, after their de novo synthesis, phospholipids can be remodelled by acyl exchange with one and/or two acyl chains exchanged at the sn-1 and/or sn-2 position. Based on shotgun lipidomics of the reference and mlg1Δ strains, as well as biochemical assays for acyltransferase activities, we identified an additional remodelling activity for Mlg1p, namely, incorporation of palmitic acid into the sn-1 position of PS and PE. By using confocal microscopy and subcellular fractionation, we also found that this acyltransferase is located in ER membranes associated with mitochondria, a finding that highlights the importance of these organelles in the global cellular metabolism of lipids.
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Affiliation(s)
- Patricia Laquel
- Univ. Bordeaux, CNRS, LBM, UMR 5200, Villenave d'Ornon, France
| | - Sophie Ayciriex
- Univ. Lyon, CNRS, Université Claude Bernard Lyon 1, ISA, UMR 5280, Villeurbanne, France
| | | | | | - Louise Fougère
- Univ. Bordeaux, CNRS, LBM, UMR 5200, Villenave d'Ornon, France
| | | | | | | | - Eric Testet
- Univ. Bordeaux, CNRS, LBM, UMR 5200, Villenave d'Ornon, France
- Bordeaux INP, LBM, UMR 5200, Villenave d'Ornon, France
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2
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Barbosa AD, Siniossoglou S. Membranes that make fat: roles of membrane lipids as acyl donors for triglyceride synthesis and organelle function. FEBS Lett 2024; 598:1226-1234. [PMID: 38140812 DOI: 10.1002/1873-3468.14793] [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: 11/02/2023] [Revised: 12/05/2023] [Accepted: 12/15/2023] [Indexed: 12/24/2023]
Abstract
Triglycerides constitute an inert storage form for fatty acids deposited in lipid droplets and are mobilized to provide metabolic energy or membrane building blocks. The biosynthesis of triglycerides is highly conserved within eukaryotes and normally involves the sequential esterification of activated fatty acids with a glycerol backbone. Some eukaryotes, however, can also use cellular membrane lipids as direct fatty acid donors for triglyceride synthesis. The biological significance of a pathway that generates triglycerides at the expense of organelle membranes has remained elusive. Here we review current knowledge on how cells use membrane lipids as fatty acid donors for triglyceride synthesis and discuss the hypothesis that a primary function of this pathway is to regulate membrane lipid remodeling and organelle function.
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Affiliation(s)
- Antonio D Barbosa
- Cambridge Institute for Medical Research, University of Cambridge, UK
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3
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Hrach VL, King WR, Nelson LD, Conklin S, Pollock JA, Patton-Vogt J. The acyltransferase Gpc1 is both a target and an effector of the unfolded protein response in Saccharomyces cerevisiae. J Biol Chem 2023; 299:104884. [PMID: 37269946 PMCID: PMC10331479 DOI: 10.1016/j.jbc.2023.104884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/25/2023] [Accepted: 05/27/2023] [Indexed: 06/05/2023] Open
Abstract
The unfolded protein response (UPR) is sensitive to proteotoxic and membrane bilayer stress, both of which are sensed by the ER protein Ire1. When activated, Ire1 splices HAC1 mRNA, producing a transcription factor that targets genes involved in proteostasis and lipid metabolism, among others. The major membrane lipid phosphatidylcholine (PC) is subject to phospholipase-mediated deacylation, producing glycerophosphocholine (GPC), followed by reacylation of GPC through the PC deacylation/reacylation pathway (PC-DRP). The reacylation events occur via a two-step process catalyzed first by the GPC acyltransferase Gpc1, followed by acylation of the lyso-PC molecule by Ale1. However, whether Gpc1 is critical for ER bilayer homeostasis is unclear. Using an improved method for C14-choline-GPC radiolabeling, we first show that loss of Gpc1 results in abrogation of PC synthesis through PC-DRP and that Gpc1 colocalizes with the ER. We then probe the role of Gpc1 as both a target and an effector of the UPR. Exposure to the UPR-inducing compounds tunicamycin, DTT, and canavanine results in a Hac1-dependent increase in GPC1 message. Further, cells lacking Gpc1 exhibit increased sensitivity to those proteotoxic stressors. Inositol limitation, known to induce the UPR via bilayer stress, also induces GPC1 expression. Finally, we show that loss of GPC1 induces the UPR. A gpc1Δ mutant displays upregulation of the UPR in strains expressing a mutant form of Ire1 that is unresponsive to unfolded proteins, indicating that bilayer stress is responsible for the observed upregulation. Collectively, our data indicate an important role for Gpc1 in yeast ER bilayer homeostasis.
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Affiliation(s)
- Victoria Lee Hrach
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - William R King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Laura D Nelson
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Shane Conklin
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - John A Pollock
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA.
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4
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Kotlova ER, Senik SV, Manzhieva BS, Kiyashko AA, Shakhova NV, Puzansky RK, Volobuev SV, Misharev AD, Serebryakov EB, Psurtseva NV. Diversity of ESI-MS Based Phosphatidylcholine Profiles in Basidiomycetes. J Fungi (Basel) 2022; 8:jof8020177. [PMID: 35205932 PMCID: PMC8879007 DOI: 10.3390/jof8020177] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/09/2022] [Accepted: 02/09/2022] [Indexed: 01/27/2023] Open
Abstract
Phosphatidylcholines (PC) are the main membrane lipid constituents comprising more than 50% of total glycerophospholipids. They coordinate a number of cell functions, particularly cell growth, homeostasis, secretion, recognition and communication. In basidial fungi PC are synthesized via the Kennedy pathway as well as through methylation of phosphatidylethanolamines (PE) and then undergo remodeling in Lands cycle that replaces fatty acids in PC molecules. The molecular profile of PC is determined by the genetic features that are characteristic for every species and depend on the environment. Here we present the results of ESI-MS based analyses of PC profiles of 38 species of basidiomycetes belonging to Agaricales (12), Polyporales (17), Russulales (5), Gleophyllales (2), Cantharellales (1), Auriculariales (1), Phallales (1). Although the variety of PC molecular species of basidiomycetes is rather diverse (20–38 molecular species in every profile), only 1–3 main molecular species represent 70–90% of total PC content. The most abundant of them are C36:4 and C36:3, followed by C34:1, C34:2, C36:5, C36:2. In the majority of basidiomycetes, C36:4 reaches up to 50–70% of total PC molecular species. Based on the results of hierarchical cluster analysis four main types of PC profiles which characterized the studied fungi independently from their taxonomic position, ecology, trophic status, and hyphal differentiation have been revealed. Comparative analyses of studied fungi using PCA method have shown that species of Polyporales differ from those of Agaricales by higher variability of PC profiles.
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Affiliation(s)
- Ekaterina R. Kotlova
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
- Correspondence:
| | - Svetlana V. Senik
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Bairta S. Manzhieva
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Anna A. Kiyashko
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Natalia V. Shakhova
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Roman K. Puzansky
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Sergei V. Volobuev
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
| | - Alexander D. Misharev
- Chemical Analysis and Materials Research Centre, Saint-Petersburg State University, 198504 Saint-Petersburg, Russia; (A.D.M.); (E.B.S.)
| | - Eugeny B. Serebryakov
- Chemical Analysis and Materials Research Centre, Saint-Petersburg State University, 198504 Saint-Petersburg, Russia; (A.D.M.); (E.B.S.)
| | - Nadezhda V. Psurtseva
- Komarov Botanical Institute, Russian Academy of Sciences RAS, 197376 Saint-Petersburg, Russia; (S.V.S.); (B.S.M.); (A.A.K.); (N.V.S.); (R.K.P.); (S.V.V.); (N.V.P.)
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5
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FSH1 encodes lysophospholipase activity in Saccharomyces cerevisiae. Biotechnol Lett 2020; 43:279-286. [PMID: 32920715 DOI: 10.1007/s10529-020-03004-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/08/2020] [Indexed: 01/05/2023]
Abstract
OBJECTIVES To elucidate the role of FSH1 (family of serine hydrolase) in lipid homeostasis. RESULTS Proteins in various species containing alpha/beta hydrolase domain are known to be involved in lipid metabolism. In silico analysis of the FSH1 gene in Saccharomyces cerevisiae revealed the presence of alpha/beta hydrolase domain (ABHD) and a lipase motif (GXSXG), however its function in lipid metabolism remained elusive. The overexpression of FSH1 in WT and fsh1Δ cells showed a significant reduction in the cellular phospholipid levels and an increase in the triacylglycerol levels and lipid droplet (LD) number. Furthermore, the purified recombinant protein Fsh1p was identified as a lysophospholipase that specifically acts on lysophosphatidylserine (LPS) and impacts the lipid homeostasis in S. cerevisiae. CONCLUSIONS These results depicted that Fsh1p has a role on lipid homeostasis and is a lysophospholipase that hydrolyzes lysophosphatidylserine (LPS).
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6
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Patton-Vogt J, de Kroon AIPM. Phospholipid turnover and acyl chain remodeling in the yeast ER. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158462. [PMID: 31146038 PMCID: PMC10716787 DOI: 10.1016/j.bbalip.2019.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/01/2019] [Accepted: 05/15/2019] [Indexed: 12/14/2022]
Abstract
The turnover of phospholipids plays an essential role in membrane lipid homeostasis by impacting both lipid head group and acyl chain composition. This review focusses on the degradation and acyl chain remodeling of the major phospholipid classes present in the ER membrane of the reference eukaryote Saccharomyces cerevisiae, i.e. phosphatidylcholine (PC), phosphatidylinositol (PI) and phosphatidylethanolamine (PE). Phospholipid turnover reactions are introduced, and the occurrence and important functions of phospholipid remodeling in higher eukaryotes are briefly summarized. After presenting an inventory of established mechanisms of phospholipid acyl chain exchange, current knowledge of phospholipid degradation and remodeling by phospholipases and acyltransferases localized to the yeast ER is summarized. PC is subject to the PC deacylation-reacylation remodeling pathway (PC-DRP) involving a phospholipase B, the recently identified glycerophosphocholine acyltransferase Gpc1p, and the broad specificity acyltransferase Ale1p. PI is post-synthetically enriched in C18:0 acyl chains by remodeling reactions involving Cst26p. PE may undergo turnover by the phospholipid: diacylglycerol acyltransferase Lro1p as first step in acyl chain remodeling. Clues as to the functions of phospholipid acyl chain remodeling are discussed.
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Affiliation(s)
- Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Anton I P M de Kroon
- Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands.
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7
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Anaokar S, Kodali R, Jonik B, Renne MF, Brouwers JFHM, Lager I, de Kroon AIPM, Patton-Vogt J. The glycerophosphocholine acyltransferase Gpc1 is part of a phosphatidylcholine (PC)-remodeling pathway that alters PC species in yeast. J Biol Chem 2018; 294:1189-1201. [PMID: 30514764 DOI: 10.1074/jbc.ra118.005232] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/27/2018] [Indexed: 12/22/2022] Open
Abstract
Phospholipase B-mediated hydrolysis of phosphatidylcholine (PC) results in the formation of free fatty acids and glycerophosphocholine (GPC) in the yeast Saccharomyces cerevisiae GPC can be reacylated by the glycerophosphocholine acyltransferase Gpc1, which produces lysophosphatidylcholine (LPC), and LPC can be converted to PC by the lysophospholipid acyltransferase Ale1. Here, we further characterized the regulation and function of this distinct PC deacylation/reacylation pathway in yeast. Through in vitro and in vivo experiments, we show that Gpc1 and Ale1 are the major cellular GPC and LPC acyltransferases, respectively. Importantly, we report that Gpc1 activity affects the PC species profile. Loss of Gpc1 decreased the levels of monounsaturated PC species and increased those of diunsaturated PC species, whereas Gpc1 overexpression had the opposite effects. Of note, Gpc1 loss did not significantly affect phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine profiles. Our results indicate that Gpc1 is involved in postsynthetic PC remodeling that produces more saturated PC species. qRT-PCR analyses revealed that GPC1 mRNA abundance is regulated coordinately with PC biosynthetic pathways. Inositol availability, which regulates several phospholipid biosynthetic genes, down-regulated GPC1 expression at the mRNA and protein levels and, as expected, decreased levels of monounsaturated PC species. Finally, loss of GPC1 decreased stationary phase viability in inositol-free medium. These results indicate that Gpc1 is part of a postsynthetic PC deacylation/reacylation remodeling pathway (PC-DRP) that alters the PC species profile, is regulated in coordination with other major lipid biosynthetic pathways, and affects yeast growth.
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Affiliation(s)
- Sanket Anaokar
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282
| | - Ravindra Kodali
- Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282
| | - Benjamin Jonik
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282
| | - Mike F Renne
- Department of Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, 3584 CH Utrecht, The Netherlands
| | - Jos F H M Brouwers
- Department of Biochemistry and Cell Biology, Institute of Biomembranes, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, SE-230 53 Alnarp, Sweden
| | - Anton I P M de Kroon
- Department of Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, 3584 CH Utrecht, The Netherlands
| | - Jana Patton-Vogt
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282.
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8
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du Plessis M, Franken J, Bauer FF. Carnitine Requires Choline to Exert Physiological Effects in Saccharomyces cerevisiae. Front Microbiol 2018; 9:1362. [PMID: 30034373 PMCID: PMC6043790 DOI: 10.3389/fmicb.2018.01362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/05/2018] [Indexed: 11/25/2022] Open
Abstract
L-Carnitine is a key metabolite in the energy metabolism of eukaryotic cells, functioning as a shuttling molecule for activated acyl-residues between cellular compartments. In higher eukaryotes this function is essential, and defects in carnitine metabolism has severe effects on fatty acid and carbon metabolism. Carnitine supplementation has been associated with an array of mostly beneficial impacts in higher eukaryotic cells, including stress protection and regulation of redox metabolism in diseased cells. Some of these phenotypes have no obvious link to the carnitine shuttle, and suggest that carnitine has as yet unknown shuttle-independent functions. The existence of shuttle-independent functions has also been suggested in Saccharomyces cerevisiae, including a beneficial effect during hydrogen peroxide stress and a detrimental impact when carnitine is co-supplemented with the reducing agent dithiothreitol (DTT). Here we used these two distinct yeast phenotypes to screen for potential genetic factors that suppress the shuttle independent physiological effects of carnitine. Two deletion strains, Δcho2 and Δopi3, coding for enzymes that catalyze the sequential conversion of phosphatidylethanolamine to phosphatidylcholine were identified for suppressing the phenotypic effects of carnitine. Additional characterisation indicated that the suppression cannot be explained by differences in phospholipid homeostasis. The phenotypes could be reinstated by addition of extracellular choline, but show that the requirement for choline is not based on some overlapping function or the structural similarities of the two molecules. This is the first study to suggest a molecular link between a specific metabolite and carnitine-dependent, but shuttle-independent phenotypes in eukaryotes.
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Affiliation(s)
| | | | - Florian F. Bauer
- Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa
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9
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Renne MF, de Kroon AIPM. The role of phospholipid molecular species in determining the physical properties of yeast membranes. FEBS Lett 2017; 592:1330-1345. [PMID: 29265372 PMCID: PMC5947837 DOI: 10.1002/1873-3468.12944] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 11/27/2017] [Accepted: 12/11/2017] [Indexed: 12/18/2022]
Abstract
In most eukaryotes, including Saccharomyces cerevisiae, glycerophospholipids are the main membrane lipid constituents. Besides serving as general membrane ‘building blocks’, glycerophospholipids play an important role in determining the physical properties of the membrane, which are crucial for proper membrane function. To ensure optimal physical properties, membrane glycerophospholipid composition and synthesis are tightly regulated. This review will summarize our current knowledge of factors and processes determining the membrane glycerophospholipid composition of the reference eukaryote S. cerevisiae at the level of molecular species. Extrapolating from relevant model membrane data, we also discuss how modulation of the molecular species composition can regulate membrane physical properties.
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Affiliation(s)
- Mike F. Renne
- Membrane Biochemistry & BiophysicsDepartment of ChemistryBijvoet Center for Biomolecular Research & Institute of BiomembranesUtrecht Universitythe Netherlands
| | - Anton I. P. M. de Kroon
- Membrane Biochemistry & BiophysicsDepartment of ChemistryBijvoet Center for Biomolecular Research & Institute of BiomembranesUtrecht Universitythe Netherlands
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10
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Péter M, Glatz A, Gudmann P, Gombos I, Török Z, Horváth I, Vígh L, Balogh G. Metabolic crosstalk between membrane and storage lipids facilitates heat stress management in Schizosaccharomyces pombe. PLoS One 2017; 12:e0173739. [PMID: 28282432 PMCID: PMC5345867 DOI: 10.1371/journal.pone.0173739] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 02/24/2017] [Indexed: 12/28/2022] Open
Abstract
Cell membranes actively participate in stress sensing and signalling. Here we present the first in-depth lipidomic analysis to characterize alterations in the fission yeast Schizosaccharomyces pombe in response to mild heat stress (HS). The lipidome was assessed by a simple one-step methanolic extraction. Genetic manipulations that altered triglyceride (TG) content in the absence or presence of HS gave rise to distinct lipidomic fingerprints for S. pombe. Cells unable to produce TG demonstrated long-lasting growth arrest and enhanced signalling lipid generation. Our results reveal that metabolic crosstalk between membrane and storage lipids facilitates homeostatic maintenance of the membrane physical/chemical state that resists negative effects on cell growth and viability in response to HS. We propose a novel stress adaptation mechanism in which heat-induced TG synthesis contributes to membrane rigidization by accommodating unsaturated fatty acids of structural lipids, enabling their replacement by newly synthesized saturated fatty acids.
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Affiliation(s)
- Mária Péter
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Attila Glatz
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Péter Gudmann
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Imre Gombos
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Zsolt Török
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Ibolya Horváth
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Vígh
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Gábor Balogh
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- * E-mail:
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11
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Lipidomics in research on yeast membrane lipid homeostasis. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:797-799. [PMID: 28219720 DOI: 10.1016/j.bbalip.2017.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 02/13/2017] [Accepted: 02/15/2017] [Indexed: 11/21/2022]
Abstract
Mass spectrometry is increasingly used in research on membrane lipid homeostasis, both in analyses of the steady state lipidome at the level of molecular lipid species, and in pulse-chase approaches employing stable isotope-labeled lipid precursors addressing the dynamics of lipid metabolism. Here my experience with, and view on mass spectrometry-based lipid analysis is presented, with emphasis on aspects of quantification of membrane lipid composition of the yeast Saccharomyces cerevisiae. This article is part of a Special Issue entitled: BBALIP_Lipidomics Opinion Articles edited by Sepp Kohlwein.
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12
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Oelkers P, Pokhrel K. Four Acyltransferases Uniquely Contribute to Phospholipid Heterogeneity in Saccharomyces cerevisiae. Lipid Insights 2016; 9:31-41. [PMID: 27920551 PMCID: PMC5127605 DOI: 10.4137/lpi.s40597] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/25/2016] [Accepted: 10/25/2016] [Indexed: 11/14/2022] Open
Abstract
Diverse acyl-CoA species and acyltransferase isoenzymes are components of a complex system that synthesizes glycerophospholipids and triacylglycerols. Saccharomyces cerevisiae has four main acyl-CoA species, two main glycerol-3-phosphate 1-O-acyltransferases (Gat1p, Gat2p), and two main 1-acylglycerol-3-phosphate O-acyltransferases (Lpt1p, Slc1p). The in vivo contribution of these isoenzymes to phospholipid heterogeneity was determined using haploids with compound mutations: gat1Δlpt1Δ, gat2Δlpt1Δ, gat1Δslc1Δ, and gat2Δslc1Δ. All mutations mildly reduced [3H]palmitic acid incorporation into phospholipids relative to triacylglycerol. Electrospray ionization tandem mass spectrometry identified few differences from wild type in gat1Δlpt1Δ, dramatic differences in gat2Δslc1Δ, and intermediate changes in gat2Δlpt1Δ and gat1Δslc1Δ. Yeast expressing Gat1p and Lpt1p had phospholipids enriched with acyl chains that were unsaturated, 18 carbons long, and paired for length. These alterations prevented growth at 18.5°C and in 10% ethanol. Therefore, Gat2p and Slc1p dictate phospholipid acyl chain composition in rich media at 30°C. Slc1p selectively pairs acyl chains of different lengths.
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Affiliation(s)
- Peter Oelkers
- Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI, USA
| | - Keshav Pokhrel
- Department of Mathematics and Statistics, University of Michigan-Dearborn, Dearborn, MI, USA
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13
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Głąb B, Beganovic M, Anaokar S, Hao MS, Rasmusson AG, Patton-Vogt J, Banaś A, Stymne S, Lager I. Cloning of Glycerophosphocholine Acyltransferase (GPCAT) from Fungi and Plants: A NOVEL ENZYME IN PHOSPHATIDYLCHOLINE SYNTHESIS. J Biol Chem 2016; 291:25066-25076. [PMID: 27758859 PMCID: PMC5122774 DOI: 10.1074/jbc.m116.743062] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 10/06/2016] [Indexed: 12/22/2022] Open
Abstract
Glycero-3-phosphocholine (GPC), the product of the complete deacylation of phosphatidylcholine (PC), was long thought to not be a substrate for reacylation. However, it was recently shown that cell-free extracts from yeast and plants could acylate GPC with acyl groups from acyl-CoA. By screening enzyme activities of extracts derived from a yeast knock-out collection, we were able to identify and clone the yeast gene (GPC1) encoding the enzyme, named glycerophosphocholine acyltransferase (GPCAT). By homology search, we also identified and cloned GPCAT genes from three plant species. All enzymes utilize acyl-CoA to acylate GPC, forming lyso-PC, and they show broad acyl specificities in both yeast and plants. In addition to acyl-CoA, GPCAT efficiently utilizes LPC and lysophosphatidylethanolamine as acyl donors in the acylation of GPC. GPCAT homologues were found in the major eukaryotic organism groups but not in prokaryotes or chordates. The enzyme forms its own protein family and does not contain any of the acyl binding or lipase motifs that are present in other studied acyltransferases and transacylases. In vivo labeling studies confirm a role for Gpc1p in PC biosynthesis in yeast. It is postulated that GPCATs contribute to the maintenance of PC homeostasis and also have specific functions in acyl editing of PC (e.g. in transferring acyl groups modified at the sn-2 position of PC to the sn-1 position of this molecule in plant cells).
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Affiliation(s)
- Bartosz Głąb
- From the Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-822 Gdańsk, Poland
| | - Mirela Beganovic
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden
| | - Sanket Anaokar
- the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282, and
| | - Meng-Shu Hao
- the Department of Biology, Lund University, Biology Building A, Sölvegatan 35, 223 62 Lund, Sweden
| | - Allan G Rasmusson
- the Department of Biology, Lund University, Biology Building A, Sölvegatan 35, 223 62 Lund, Sweden
| | - Jana Patton-Vogt
- the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282, and
| | - Antoni Banaś
- From the Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-822 Gdańsk, Poland
| | - Sten Stymne
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden
| | - Ida Lager
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden,
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14
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Renne MF, Bao X, De Smet CH, de Kroon AIPM. Lipid Acyl Chain Remodeling in Yeast. Lipid Insights 2016; 8:33-40. [PMID: 26819558 PMCID: PMC4720183 DOI: 10.4137/lpi.s31780] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 11/21/2015] [Indexed: 11/05/2022] Open
Abstract
Membrane lipid homeostasis is maintained by de novo synthesis, intracellular transport, remodeling, and degradation of lipid molecules. Glycerophospholipids, the most abundant structural component of eukaryotic membranes, are subject to acyl chain remodeling, which is defined as the post-synthetic process in which one or both acyl chains are exchanged. Here, we review studies addressing acyl chain remodeling of membrane glycerophospholipids in Saccharomyces cerevisiae, a model organism that has been successfully used to investigate lipid synthesis and its regulation. Experimental evidence for the occurrence of phospholipid acyl chain exchange in cardiolipin, phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine is summarized, including methods and tools that have been used for detecting remodeling. Progress in the identification of the enzymes involved is reported, and putative functions of acyl chain remodeling in yeast are discussed.
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Affiliation(s)
- Mike F Renne
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Xue Bao
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Cedric H De Smet
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands.; Present address: Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Anton I P M de Kroon
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
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15
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Neess D, Bek S, Engelsby H, Gallego SF, Færgeman NJ. Long-chain acyl-CoA esters in metabolism and signaling: Role of acyl-CoA binding proteins. Prog Lipid Res 2015; 59:1-25. [PMID: 25898985 DOI: 10.1016/j.plipres.2015.04.001] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/11/2015] [Accepted: 04/09/2015] [Indexed: 02/03/2023]
Abstract
Long-chain fatty acyl-CoA esters are key intermediates in numerous lipid metabolic pathways, and recognized as important cellular signaling molecules. The intracellular flux and regulatory properties of acyl-CoA esters have been proposed to be coordinated by acyl-CoA-binding domain containing proteins (ACBDs). The ACBDs, which comprise a highly conserved multigene family of intracellular lipid-binding proteins, are found in all eukaryotes and ubiquitously expressed in all metazoan tissues, with distinct expression patterns for individual ACBDs. The ACBDs are involved in numerous intracellular processes including fatty acid-, glycerolipid- and glycerophospholipid biosynthesis, β-oxidation, cellular differentiation and proliferation as well as in the regulation of numerous enzyme activities. Little is known about the specific roles of the ACBDs in the regulation of these processes, however, recent studies have gained further insights into their in vivo functions and provided further evidence for ACBD-specific functions in cellular signaling and lipid metabolic pathways. This review summarizes the structural and functional properties of the various ACBDs, with special emphasis on the function of ACBD1, commonly known as ACBP.
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Affiliation(s)
- Ditte Neess
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Signe Bek
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Hanne Engelsby
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Sandra F Gallego
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Nils J Færgeman
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark.
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16
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Lager I, Glab B, Eriksson L, Chen G, Banas A, Stymne S. Novel reactions in acyl editing of phosphatidylcholine by lysophosphatidylcholine transacylase (LPCT) and acyl-CoA:glycerophosphocholine acyltransferase (GPCAT) activities in microsomal preparations of plant tissues. PLANTA 2015; 241:347-58. [PMID: 25298156 PMCID: PMC4302238 DOI: 10.1007/s00425-014-2184-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 09/25/2014] [Indexed: 05/18/2023]
Abstract
Plants have lysophosphatidylcholine transacylase (LPCT) and acyl-CoA:glycerophosphocholine acyltransferase (GPCAT) activities. The combined action of LPCT and GPCAT provides a novel route of PC re-synthesis after its deacylation. Phosphatidylcholine (PC) is the major lipid in eukaryotic membranes and has a central role in overall plant lipid metabolism. It is also the site of production of polyunsaturated fatty acids in plants. The recently discovered acyl-CoA:glycerophosphocholine acyltransferase (GPCAT) activity in yeast provides a novel route of re-synthesising PC via lysophosphatidylcholine (LPC) after its deacylation. This route does not require the degradation of the glycerophosphocholine (GPC) into free choline, the activation of choline to CDP-choline, nor the utilization of CDP-choline by the CDP-choline:diacylglycerol cholinephosphotransferase. We show here that GPCAT activities also are present in membrane preparations from developing oil seeds of safflower and other species as well as in membrane preparations of roots and leaves of Arabidopsis, indicating that GPCAT activity plays a ubiquitous role in plant lipid metabolism. The last step in formation of GPC, the substrate for GPCAT, is the deacylation of LPC. Microsomal membranes of developing safflower seeds utilized LPC in LPC:LPC transacylation reactions (LPCT activities) creating PC and GPC. The results demonstrate that safflower membranes have LPCT and GPCAT activities that represent novel reactions for PC acyl editing. The physiological relevance of these reactions probably has to await identification of the enzymes catalysing these reactions.
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Affiliation(s)
- Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden,
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17
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Surlow BA, Cooley BM, Needham PG, Brodsky JL, Patton-Vogt J. Loss of Ypk1, the yeast homolog to the human serum- and glucocorticoid-induced protein kinase, accelerates phospholipase B1-mediated phosphatidylcholine deacylation. J Biol Chem 2014; 289:31591-604. [PMID: 25258318 DOI: 10.1074/jbc.m114.581157] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Ypk1, the yeast homolog of the human serum- and glucocorticoid-induced kinase (Sgk1), affects diverse cellular activities, including sphingolipid homeostasis. We now report that Ypk1 also impacts the turnover of the major phospholipid, phosphatidylcholine (PC). Pulse-chase radiolabeling reveals that a ypk1Δ mutant exhibits increased PC deacylation and glycerophosphocholine production compared with wild type yeast. Deletion of PLB1, a gene encoding a B-type phospholipase that hydrolyzes PC, in a ypk1Δ mutant curtails the increased PC deacylation. In contrast to previous data, we find that Plb1 resides in the ER and in the medium. Consistent with a link between Ypk1 and Plb1, the levels of both Plb1 protein and PLB1 message are elevated in a ypk1Δ strain compared with wild type yeast. Furthermore, deletion of PLB1 in a ypk1Δ mutant exacerbates phenotypes associated with loss of YPK1, including slowed growth and sensitivity to cell wall perturbation, suggesting that increased Plb1 activity buffers against the loss of Ypk1. Because Plb1 lacks a consensus phosphorylation site for Ypk1, we probed other processes under the control of Ypk1 that might be linked to PC turnover. Inhibition of sphingolipid biosynthesis by the drug myriocin or through utilization of a lcb1-100 mutant results in increased PLB1 expression. Furthermore, we discovered that the increase in PLB1 expression observed upon inhibition of sphingolipid synthesis or loss of Ypk1 is under the control of the Crz1 transcription factor. Taken together, these results suggest a functional interaction between Ypk1 and Plb1 in which altered sphingolipid metabolism up-regulates PLB1 expression via Crz1.
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Affiliation(s)
- Beth A Surlow
- From the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282 and
| | - Benjamin M Cooley
- From the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282 and
| | - Patrick G Needham
- the Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Jeffrey L Brodsky
- the Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Jana Patton-Vogt
- From the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282 and
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18
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Selvaraju K, Rajakumar S, Nachiappan V. Identification of a phospholipase B encoded by the LPL1 gene in Saccharomyces cerevisiae. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1842:1383-92. [PMID: 25014274 DOI: 10.1016/j.bbalip.2014.06.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 06/26/2014] [Accepted: 06/28/2014] [Indexed: 10/25/2022]
Abstract
Phospholipids also play a major role in maintaining the lipid droplet (LD) morphology. In our current study, deletion of LPL1 resulted in altered morphology of LDs and was confirmed by microscopic analysis. LPL1/YOR059c contains lipase specific motif GXSXG and acetate labeling in the LPL1 overexpressed strains depicted a decrease in glycerophospholipids and an increase in free fatty acids. The purified Lpl1p showed phospholipase activity with broader substrate specificity, acting on all glycerophospholipids primarily at sn-2 position and later at sn-1 position. Localization studies precisely revealed that Lpl1 is exclusively localized in the LD at the stationary phase. Site directed mutagenesis experiments clearly demonstrated that the lipase motif is vital for the phospholipase activity. In summary, our results demonstrate that yeast Lpl1 exerts phospholipase activity, plays a vital role in LD morphology, and its absence results in altered LD size. Based on the localization and enzyme activity we renamed YOR059c as LPL1 (LD phospholipase 1).
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Affiliation(s)
- Kandasamy Selvaraju
- Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Selvaraj Rajakumar
- Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Vasanthi Nachiappan
- Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India.
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19
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Kishino H, Eguchi H, Takagi K, Horiuchi H, Fukuda R, Ohta A. Acyl-chain remodeling of dioctanoyl-phosphatidylcholine in Saccharomyces cerevisiae mutant defective in de novo and salvage phosphatidylcholine synthesis. Biochem Biophys Res Commun 2014; 445:289-93. [PMID: 24491568 DOI: 10.1016/j.bbrc.2014.01.136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 01/25/2014] [Indexed: 10/25/2022]
Abstract
A yeast strain, in which endogenous phosphatidylcholine (PC) synthesis is controllable, was constructed by the replacement of the promoter of PCT1, encoding CTP:phosphocholine cytidylyltransferase, with GAL1 promoter in a double deletion mutant of PEM1 and PEM2, encoding phosphatidylethanolamine methyltransferase and phospholipid methyltransferase, respectively. This mutant did not grow in the glucose-containing medium, but the addition of dioctanoyl-phosphatidylcholine (diC8PC) supported its growth. Analyses of the metabolism of (13)C-labeled diC8PC ((methyl-(13)C)3-diC8PC) in this strain using electrospray ionization tandem mass spectrometry revealed that it was converted to PC species containing acyl residues of 16 or 18 carbons at both sn-1 and sn-2 positions. In addition, both acyl residues of (methyl-(13)C)3-diC8PC were replaced with 16:1 acyl chains in the in vitro reaction using the yeast cell extract in the presence of palmitoleoyl-CoA. These results indicate that PC containing short acyl residues was remodeled to those with acyl chains of physiological length in yeast.
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Affiliation(s)
- Hideyuki Kishino
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroki Eguchi
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Keiko Takagi
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroyuki Horiuchi
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Ryouichi Fukuda
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Akinori Ohta
- Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
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20
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Checks and balances in membrane phospholipid class and acyl chain homeostasis, the yeast perspective. Prog Lipid Res 2013; 52:374-94. [PMID: 23631861 DOI: 10.1016/j.plipres.2013.04.006] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/28/2013] [Accepted: 04/16/2013] [Indexed: 11/24/2022]
Abstract
Glycerophospholipids are the most abundant membrane lipid constituents in most eukaryotic cells. As a consequence, phospholipid class and acyl chain homeostasis are crucial for maintaining optimal physical properties of membranes that in turn are crucial for membrane function. The topic of this review is our current understanding of membrane phospholipid homeostasis in the reference eukaryote Saccharomyces cerevisiae. After introducing the physical parameters of the membrane that are kept in optimal range, the properties of the major membrane phospholipids and their contributions to membrane structure and dynamics are summarized. Phospholipid metabolism and known mechanisms of regulation are discussed, including potential sensors for monitoring membrane physical properties. Special attention is paid to processes that maintain the phospholipid class specific molecular species profiles, and to the interplay between phospholipid class and acyl chain composition when yeast membrane lipid homeostasis is challenged. Based on the reviewed studies, molecular species selectivity of the lipid metabolic enzymes, and mass action in acyl-CoA metabolism are put forward as important intrinsic contributors to membrane lipid homeostasis.
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