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How is the acyl chain composition of phosphoinositides created and does it matter? Biochem Soc Trans 2020; 47:1291-1305. [PMID: 31657437 PMCID: PMC6824679 DOI: 10.1042/bst20190205] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/27/2019] [Accepted: 10/01/2019] [Indexed: 12/11/2022]
Abstract
The phosphoinositide (PIPn) family of signalling phospholipids are central regulators in membrane cell biology. Their varied functions are based on the phosphorylation pattern of their inositol ring, which can be recognized by selective binding domains in their effector proteins and be modified by a series of specific PIPn kinases and phosphatases, which control their interconversion in a spatial and temporal manner. Yet, a unique feature of PIPns remains largely unexplored: their unusually uniform acyl chain composition. Indeed, while most phospholipids present a range of molecular species comprising acyl chains of diverse length and saturation, PIPns in several organisms and tissues show the predominance of a single hydrophobic backbone, which in mammals is composed of arachidonoyl and stearoyl chains. Despite evolution having favoured this specific PIPn configuration, little is known regarding the mechanisms and functions behind it. In this review, we explore the metabolic pathways that could control the acyl chain composition of PIPns as well as the potential roles of this selective enrichment. While our understanding of this phenomenon has been constrained largely by the technical limitations in the methods traditionally employed in the PIPn field, we believe that the latest developments in PIPn analysis should shed light onto this old question.
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Meroni M, Dongiovanni P, Longo M, Carli F, Baselli G, Rametta R, Pelusi S, Badiali S, Maggioni M, Gaggini M, Fracanzani AL, Romeo S, Gatti S, Davidson NO, Gastaldelli A, Valenti L. Mboat7 down-regulation by hyper-insulinemia induces fat accumulation in hepatocytes. EBioMedicine 2020; 52:102658. [PMID: 32058943 PMCID: PMC7026742 DOI: 10.1016/j.ebiom.2020.102658] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 12/16/2022] Open
Abstract
Background Naturally occurring variation in Membrane-bound O-acyltransferase domain-containing 7 (MBOAT7), encoding for an enzyme involved in phosphatidylinositol acyl-chain remodelling, has been associated with fatty liver and hepatic disorders. Here, we examined the relationship between hepatic Mboat7 down-regulation and fat accumulation. Methods Hepatic MBOAT7 expression was surveyed in 119 obese individuals and in experimental models. MBOAT7 was acutely silenced by antisense oligonucleotides in C57Bl/6 mice, and by CRISPR/Cas9 in HepG2 hepatocytes. Findings In obese individuals, hepatic MBOAT7 mRNA decreased from normal liver to steatohepatitis, independently of diabetes, inflammation and MBOAT7 genotype. Hepatic MBOAT7 levels were reduced in murine models of fatty liver, and by hyper-insulinemia. In wild-type mice, Mboat7 was down-regulated by refeeding and insulin, concomitantly with insulin signalling activation. Acute hepatic Mboat7 silencing promoted hepatic steatosis in vivo and enhanced expression of fatty acid transporter Fatp1. MBOAT7 deletion in hepatocytes reduced the incorporation of arachidonic acid into phosphatidylinositol, consistently with decreased enzymatic activity, determining the accumulation of saturated triglycerides, enhanced lipogenesis and FATP1 expression, while FATP1 deletion rescued the phenotype. Interpretation MBOAT7 down-regulation by hyper-insulinemia contributes to hepatic fat accumulation, impairing phosphatidylinositol remodelling and up-regulating FATP1. Funding LV was supported by MyFirst Grant AIRC n.16888, Ricerca Finalizzata Ministero della Salute RF-2016–02,364,358, Ricerca corrente Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico; LV and AG received funding from the European Union Programme Horizon 2020 (No. 777,377) for the project LITMUS-“Liver Investigation: Testing Marker Utility in Steatohepatitis”. MM was supported by Fondazione Italiana per lo Studio del Fegato (AISF) ‘Mario Coppo’ fellowship.
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Affiliation(s)
- Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Ospedale Policlinico via F Sforza 35, 20122 Milano, Italy
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy; Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milano, Italy
| | - Fabrizia Carli
- National Research Council (CNR), Institute of Clinical Physiology, Pisa, Italy
| | - Guido Baselli
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Ospedale Policlinico via F Sforza 35, 20122 Milano, Italy
| | - Raffaela Rametta
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Serena Pelusi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Ospedale Policlinico via F Sforza 35, 20122 Milano, Italy; Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Italy
| | - Sara Badiali
- Department of Surgery, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Marco Maggioni
- Department of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Melania Gaggini
- National Research Council (CNR), Institute of Clinical Physiology, Pisa, Italy
| | - Anna Ludovica Fracanzani
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Ospedale Policlinico via F Sforza 35, 20122 Milano, Italy
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden; Clinical Nutrition Department of Medical and Surgical Science, University Magna Graecia, Catanzaro, Italy
| | - Stefano Gatti
- Preclinical research center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Nicholas O Davidson
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, Italy
| | - Amalia Gastaldelli
- National Research Council (CNR), Institute of Clinical Physiology, Pisa, Italy
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Ospedale Policlinico via F Sforza 35, 20122 Milano, Italy; Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Italy.
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Saliakoura M, Reynoso-Moreno I, Pozzato C, Rossi Sebastiano M, Galié M, Gertsch J, Konstantinidou G. The ACSL3-LPIAT1 signaling drives prostaglandin synthesis in non-small cell lung cancer. Oncogene 2020; 39:2948-2960. [PMID: 32034305 PMCID: PMC7118021 DOI: 10.1038/s41388-020-1196-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/16/2020] [Accepted: 01/27/2020] [Indexed: 11/17/2022]
Abstract
Enhanced prostaglandin production promotes the development and progression of cancer. Prostaglandins are generated from arachidonic acid (AA) by the action of cyclooxygenase (COX) isoenzymes. However, how cancer cells are able to maintain an elevated supply of AA for prostaglandin production remains unclear. Here, by using lung cancer cell lines and clinically relevant KrasG12D-driven mouse models, we show that the long-chain acyl-CoA synthetase (ACSL3) channels AA into phosphatidylinositols to provide the lysophosphatidylinositol-acyltransferase 1 (LPIAT1) with a pool of AA to sustain high prostaglandin synthesis. LPIAT1 knockdown suppresses proliferation and anchorage-independent growth of lung cancer cell lines, and hinders in vivo tumorigenesis. In primary human lung tumors, the expression of LPIAT1 is elevated compared with healthy tissue, and predicts poor patient survival. This study uncovers the ACSL3-LPIAT1 axis as a requirement for the sustained prostaglandin synthesis in lung cancer with potential therapeutic value.
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Affiliation(s)
- Maria Saliakoura
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland
| | - Inés Reynoso-Moreno
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Chiara Pozzato
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland
| | | | - Mirco Galié
- Department of Neuroscience, Biomedicine and Movement, University of Verona, 37134, Verona, Italy
| | - Jürg Gertsch
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
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Blunsom NJ, Cockcroft S. CDP-Diacylglycerol Synthases (CDS): Gateway to Phosphatidylinositol and Cardiolipin Synthesis. Front Cell Dev Biol 2020; 8:63. [PMID: 32117988 PMCID: PMC7018664 DOI: 10.3389/fcell.2020.00063] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 01/22/2020] [Indexed: 12/15/2022] Open
Abstract
Cytidine diphosphate diacylglycerol (CDP-DAG) is a key intermediate in the synthesis of phosphatidylinositol (PI) and cardiolipin (CL). Both PI and CL have highly specialized roles in cells. PI can be phosphorylated and these phosphorylated derivatives play major roles in signal transduction, membrane traffic, and maintenance of the actin cytoskeletal network. CL is the signature lipid of mitochondria and has a plethora of functions including maintenance of cristae morphology, mitochondrial fission, and fusion and for electron transport chain super complex formation. Both lipids are synthesized in different organelles although they share the common intermediate, CDP-DAG. CDP-DAG is synthesized from phosphatidic acid (PA) and CTP by enzymes that display CDP-DAG synthase activities. Two families of enzymes, CDS and TAMM41, which bear no sequence or structural relationship, have now been identified. TAMM41 is a peripheral membrane protein localized in the inner mitochondrial membrane required for CL synthesis. CDS enzymes are ancient integral membrane proteins found in all three domains of life. In mammals, they provide CDP-DAG for PI synthesis and for phosphatidylglycerol (PG) and CL synthesis in prokaryotes. CDS enzymes are critical for maintaining phosphoinositide levels during phospholipase C (PLC) signaling. Hydrolysis of PI (4,5) bisphosphate by PLC requires the resynthesis of PI and CDS enzymes catalyze the rate-limiting step in the process. In mammals, the protein products of two CDS genes (CDS1 and CDS2) localize to the ER and it is suggested that CDS2 is the major CDS for this process. Expression of CDS enzymes are regulated by transcription factors and CDS enzymes may also contribute to CL synthesis in mitochondria. Studies of CDS enzymes in protozoa reveal spatial segregation of CDS enzymes from the rest of the machinery required for both PI and CL synthesis identifying a key gap in our understanding of how CDP-DAG can cross the different membrane compartments in protozoa and in mammals.
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Affiliation(s)
| | - Shamshad Cockcroft
- Division of Biosciences, Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
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Neumann CKA, Silver DJ, Venkateshwari V, Zhang R, Traughber CA, Przybycin C, Bayik D, Smith JD, Lathia JD, Rini BI, Brown JM. MBOAT7-driven phosphatidylinositol remodeling promotes the progression of clear cell renal carcinoma. Mol Metab 2020; 34:136-145. [PMID: 32180553 PMCID: PMC7033598 DOI: 10.1016/j.molmet.2020.01.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 01/21/2020] [Indexed: 12/28/2022] Open
Abstract
Objective The most common kidney cancer, clear cell renal cell carcinoma (ccRCC), is closely associated with obesity. The “clear cell” variant of RCC gets its name from the large lipid droplets that accumulate in the tumor cells. Although renal lipid metabolism is altered in ccRCC, the mechanisms and lipids driving this are not well understood. Methods We used shotgun lipidomics in human ccRCC tumors and matched normal adjacent renal tissue. To assess MBOAT7s gene expression across tumor severity, we examined histologically graded human ccRCC samples. We then utilized genome editing in ccRCC cell lines to understand the role of MBOAT7 in ccRCC progression. Results We identified a lipid signature for ccRCC that includes an increase in arachidonic acid-enriched phosphatidylinositols (AA-PI). In parallel, we found that ccRCC tumors have increased expression of acyltransferase enzyme membrane bound O-acyltransferase domain containing 7 (MBOAT7) that contributes to AA-PI synthesis. In ccRCC patients, MBOAT7 expression increases with tumor grade, and increased MBOAT7 expression correlates with poor survival. Genetic deletion of MBOAT7 in ccRCC cells decreases proliferation and induces cell cycle arrest, and MBOAT7−/− cells fail to form tumors in vivo. RNAseq of MBOAT7−/− cells identified alterations in cell migration and extracellular matrix organization that were functionally validated in migration assays. Conclusions This study highlights the accumulation of AA-PI in ccRCC and demonstrates a novel way to decrease the AA-PI pool in ccRCC by limiting MBOAT7. Our data reveal that metastatic ccRCC is associated with altered AA-PI metabolism and identify MBOAT7 as a novel target in advanced ccRCC.
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Affiliation(s)
- Chase K A Neumann
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Daniel J Silver
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Varadharajan Venkateshwari
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Renliang Zhang
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - C Alicia Traughber
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Christopher Przybycin
- Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Defne Bayik
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Jonathan D Smith
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Justin D Lathia
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA; Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, OH, 44195, USA; Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Brian I Rini
- Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland Clinic Cleveland, OH, 44195, USA; Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - J Mark Brown
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA; Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, 44106, USA; Center for Microbiome and Human Health, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA.
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Bosello Travain V, Miotto G, Vučković AM, Cozza G, Roveri A, Toppo S, Ursini F, Venerando R, Zaccarin M, Maiorino M. Lack of glutathione peroxidase-8 in the ER impacts on lipid composition of HeLa cells microsomal membranes. Free Radic Biol Med 2020; 147:80-89. [PMID: 31857233 DOI: 10.1016/j.freeradbiomed.2019.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 01/04/2023]
Abstract
GPx8 is a glutathione peroxidase homolog inserted in the membranes of endoplasmic reticulum (ER), where it seemingly plays a role in controlling redox status by preventing the spill of H2O2. We addressed the impact of GPx8 silencing on the lipidome of microsomal membranes, using stably GPx8-silenced HeLa cells. The two cell lines were clearly separated by Principal Component Analysis (PCA) and Partial Least Square Discriminant analysis (PLS-DA) of lipidome. Considering in detail the individual lipid classes, we observed that unsaturated glycerophospholipids (GPL) decreased, while only in phosphatidylinositols (PI) a substitution of monounsaturated fatty acids (MUFA) for polyunsaturated fatty acids (PUFA) was observed. Among sphingolipids (SL), ceramides (CER) decreased while sphingomyelins (SM) and neutral glycophingolipids (nGSL) increased. Here, in addition, longer chains than in controls in the amide fatty acid were present. The increase up to four folds of the CER (d18:1; c24:0) containing three hexose units, was the most remarkable species increasing in the differential lipidome of siGPx8 cells. Quantitative RT-PCR complied with lipidomic analysis specifically showing an increased expression of: i) acyl-CoA synthetase 5 (ACSL5); ii) CER synthase 2 and 4; iii) CER transporter (CERT); iv) UDP-glucosyl transferase (UDP-GlcT), associated to a decreased expression of UDP-galactosyl transferase (UDP-GalT). A role of the unfolded protein response (UPR) and the spliced form of the transcription factor XBP1 on the transcriptional changes of GPx8 silenced cells was ruled-out. Similarly, also the involvement of Nrf2 and NF-κB. Altogether our results indicate that GPx8-silencing of HeLa yields a membrane depleted by about 24% of polyunsaturated GPL and a corresponding increase of saturated or monounsaturated SM and specific nGSL. This is tentatively interpreted as an adaptive mechanism leading to an increased resistance to radical oxidations. Moreover, the marked shift of fatty acid composition of PI emerges as a possibly relevant issue in respect to the impact of GPx8 on signaling pathways.
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Affiliation(s)
- Valentina Bosello Travain
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Giovanni Miotto
- CRIBI Biotechnology Center, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Ana-Marija Vučković
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Stefano Toppo
- CRIBI Biotechnology Center, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Rina Venerando
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
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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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Wilson KA, Wang L, MacDermott-Opeskin H, O'Mara ML. The Fats of Life: Using Computational Chemistry to Characterise the Eukaryotic Cell Membrane. Aust J Chem 2020. [DOI: 10.1071/ch19353] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Our current knowledge of the structural dynamics and complexity of lipid bilayers is still developing. Computational techniques, especially molecular dynamics simulations, have increased our understanding significantly as they allow us to model functions that cannot currently be experimentally resolved. Here we review available computational tools and techniques, the role of the major lipid species, insights gained into lipid bilayer structure and function from molecular dynamics simulations, and recent progress towards the computational modelling of the physiological complexity of eukaryotic lipid bilayers.
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Kawashima M, Tokiwa M, Nishimura T, Kawata Y, Sugimoto M, Kataoka TR, Sakurai T, Iwaisako K, Suzuki E, Hagiwara M, Harris AL, Toi M. High-resolution imaging mass spectrometry combined with transcriptomic analysis identified a link between fatty acid composition of phosphatidylinositols and the immune checkpoint pathway at the primary tumour site of breast cancer. Br J Cancer 2020; 122:245-257. [PMID: 31819188 PMCID: PMC7051979 DOI: 10.1038/s41416-019-0662-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 11/07/2019] [Accepted: 11/07/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The fatty acid (FA) composition of phosphatidylinositols (PIs) is tightly regulated in mammalian tissue since its disruption impairs normal cellular functions. We previously found its significant alteration in breast cancer by using matrix-assisted laser desorption and ionisation imaging mass spectrometry (MALDI-IMS). METHODS We visualised the histological distribution of PIs containing different FAs in 65 primary breast cancer tissues using MALDI-IMS and investigated its association with clinicopathological features and gene expression profiles. RESULTS Normal ductal cells (n = 7) predominantly accumulated a PI containing polyunsaturated FA (PI-PUFA), PI(18:0/20:4). PI(18:0/20:4) was replaced by PIs containing monounsaturated FA (PIs-MUFA) in all non-invasive cancer cells (n = 12). While 54% of invasive cancer cells (n = 27) also accumulated PIs-MUFA, 46% of invasive cancer cells (n = 23) accumulated the PIs-PUFA, PI(18:0/20:3) and PI(18:0/20:4). The accumulation of PI(18:0/20:3) was associated with higher incidence of lymph node metastasis and activation of the PD-1-related immune checkpoint pathway. Fatty acid-binding protein 7 was identified as a putative molecule controlling PI composition. CONCLUSIONS MALDI-IMS identified PI composition associated with invasion and nodal metastasis of breast cancer. The accumulation of PI(18:0/20:3) could affect the PD-1-related immune checkpoint pathway, although its precise mechanism should be further validated.
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Affiliation(s)
- Masahiro Kawashima
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan.
- Molecular Oncology Laboratories, Wheaterall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK.
| | - Mariko Tokiwa
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan
| | - Tomomi Nishimura
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan
| | - Yukiko Kawata
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan
| | - Masahiro Sugimoto
- Health Promotion and Preemptive Medicine, Research and Development Center for Minimally Invasive Therapies, Tokyo Medical University, Sinjuku-ku, Tokyo, 160-8402, Japan
| | - Tatsuki R Kataoka
- Department of Diagnostic Pathology, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Takaki Sakurai
- Department of Diagnostic Pathology, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Keiko Iwaisako
- Department of Target Therapy Oncology, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Eiji Suzuki
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-Cho, Sakyo-ku, Kyoto, 606-8501, Japan
- Medical Research Support Center, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-Cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Adrian L Harris
- Molecular Oncology Laboratories, Wheaterall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Masakazu Toi
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606 8507, Japan
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Valentine WJ, Hashidate-Yoshida T, Yamamoto S, Shindou H. Biosynthetic Enzymes of Membrane Glycerophospholipid Diversity as Therapeutic Targets for Drug Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1274:5-27. [PMID: 32894505 DOI: 10.1007/978-3-030-50621-6_2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Biophysical properties of membranes are dependent on their glycerophospholipid compositions. Lysophospholipid acyltransferases (LPLATs) selectively incorporate fatty chains into lysophospholipids to affect the fatty acid composition of membrane glycerophospholipids. Lysophosphatidic acid acyltransferases (LPAATs) of the 1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) family incorporate fatty chains into phosphatidic acid during the de novo glycerophospholipid synthesis in the Kennedy pathway. Other LPLATs of both the AGPAT and the membrane bound O-acyltransferase (MBOAT) families further modify the fatty chain compositions of membrane glycerophospholipids in the remodeling pathway known as the Lands' cycle. The LPLATs functioning in these pathways possess unique characteristics in terms of their biochemical activities, regulation of expressions, and functions in various biological contexts. Essential physiological functions for LPLATs have been revealed in studies using gene-deficient mice, and important roles for several enzymes are also indicated in human diseases where their mutation or dysregulation causes or contributes to the pathological condition. Now several LPLATs are emerging as attractive therapeutic targets, and further understanding of the mechanisms underlying their physiological and pathological roles will aid in the development of novel therapies to treat several diseases that involve altered glycerophospholipid metabolism.
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Affiliation(s)
- William J Valentine
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan. .,Department of Molecular Therapy, National Center of Neurology and Psychiatry, Tokyo, Japan.
| | | | - Shota Yamamoto
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan. .,Department of Lipid Science, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. .,Japan Agency for Medical Research and Development, Tokyo, Japan.
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61
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Pemberton JG, Kim YJ, Balla T. Integrated regulation of the phosphatidylinositol cycle and phosphoinositide-driven lipid transport at ER-PM contact sites. Traffic 2019; 21:200-219. [PMID: 31650663 DOI: 10.1111/tra.12709] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/02/2019] [Accepted: 10/16/2019] [Indexed: 12/20/2022]
Abstract
Among the structural phospholipids that form the bulk of eukaryotic cell membranes, phosphatidylinositol (PtdIns) is unique in that it also serves as the common precursor for low-abundance regulatory lipids, collectively referred to as polyphosphoinositides (PPIn). The metabolic turnover of PPIn species has received immense attention because of the essential functions of these lipids as universal regulators of membrane biology and their dysregulation in numerous human pathologies. The diverse functions of PPIn lipids occur, in part, by orchestrating the spatial organization and conformational dynamics of peripheral or integral membrane proteins within defined subcellular compartments. The emerging role of stable contact sites between adjacent membranes as specialized platforms for the coordinate control of ion exchange, cytoskeletal dynamics, and lipid transport has also revealed important new roles for PPIn species. In this review, we highlight the importance of membrane contact sites formed between the endoplasmic reticulum (ER) and plasma membrane (PM) for the integrated regulation of PPIn metabolism within the PM. Special emphasis will be placed on non-vesicular lipid transport during control of the PtdIns biosynthetic cycle as well as toward balancing the turnover of the signaling PPIn species that define PM identity.
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Affiliation(s)
- Joshua G Pemberton
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Yeun Ju Kim
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
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62
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Khan S, Rawlins LE, Harlalka GV, Umair M, Ullah A, Shahzad S, Javed M, Baple EL, Crosby AH, Ahmad W, Gul A. Homozygous variants in the HEXB and MBOAT7 genes underlie neurological diseases in consanguineous families. BMC MEDICAL GENETICS 2019; 20:199. [PMID: 31852446 PMCID: PMC6921424 DOI: 10.1186/s12881-019-0907-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 10/15/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Neurological disorders are a common cause of morbidity and mortality within Pakistani populations. It is one of the most important challenges in healthcare, with significant life-long socio-economic burden. METHODS We investigated the cause of disease in three Pakistani families in individuals with unexplained autosomal recessive neurological conditions, using both genome-wide SNP mapping and whole exome sequencing (WES) of affected individuals. RESULTS We identified a homozygous splice site variant (NM_000521:c.445 + 1G > T) in the hexosaminidase B (HEXB) gene confirming a diagnosis of Sandhoff disease (SD; type II GM2-gangliosidosis), an autosomal recessive lysosomal storage disorder caused by deficiency of hexosaminidases in a single family. In two further unrelated families, we identified a homozygous frameshift variant (NM_024298.3:c.758_778del; p.Glu253_Ala259del) in membrane-bound O-acyltransferase family member 7 (MBOAT7) as the likely cause of disease. MBOAT7 gene variants have recently been identified as a cause of intellectual disability (ID), seizures and autistic features. CONCLUSIONS We identified two metabolic disorders of lipid biosynthesis within three Pakistani families presenting with undiagnosed neurodevelopmental conditions. These findings enabled an accurate neurological disease diagnosis to be provided for these families, facilitating disease management and genetic counselling within this population. This study consolidates variation within MBOAT7 as a cause of neurodevelopmental disorder, broadens knowledge of the clinical outcomes associated with MBOAT7-related disorder, and confirms the likely presence of a regionally prevalent founder variant (c.758_778del; p.Glu253_Ala259del) in Pakistan.
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Affiliation(s)
- Shazia Khan
- Department of Biological Sciences, International Islamic University Islamabad, H-10, Islamabad, 44000, Pakistan.,Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK.,Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Lettie E Rawlins
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK.,Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Gladstone Road, Exeter, EX1 2ED, UK
| | - Gaurav V Harlalka
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK.,Rajarshi Shahu College of Pharmacy, Malvihir Buldana, Maharashtra, Buldana, 443001, India
| | - Muhammad Umair
- Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard-Health Affairs (MNGHA), P.O. Box 3660, Riyadh, 11481, Kingdom of Saudi Arabia
| | - Asmat Ullah
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.,Department of Molecular Biology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Shaheen Shahzad
- Department of Biological Sciences, International Islamic University Islamabad, H-10, Islamabad, 44000, Pakistan
| | - Muhammad Javed
- National Institute for Genomics & Advanced Biotechnology, NARC, Islamabad, 45500, Pakistan
| | - Emma L Baple
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK.,Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Gladstone Road, Exeter, EX1 2ED, UK
| | - Andrew H Crosby
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Wasim Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Asma Gul
- Department of Biological Sciences, International Islamic University Islamabad, H-10, Islamabad, 44000, Pakistan.
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63
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Dong XC. PNPLA3-A Potential Therapeutic Target for Personalized Treatment of Chronic Liver Disease. Front Med (Lausanne) 2019; 6:304. [PMID: 31921875 PMCID: PMC6927947 DOI: 10.3389/fmed.2019.00304] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 12/02/2019] [Indexed: 01/10/2023] Open
Abstract
Patatin-like phospholipase domain-containing protein 3 (PNPLA3) is a lipid droplet-associated protein that has been shown to have hydrolase activity toward triglycerides and retinyl esters. The first evidence of PNPLA3 being associated with fatty liver disease was revealed by a genome-wide association study (GWAS) of Hispanic, African American, and European American individuals in the Dallas Heart Study back in 2008. Since then, numerous GWAS reports have shown that PNPLA3 rs738409[G] (148M) variant is associated with hepatic triglyceride accumulation (steatosis), inflammation, fibrosis, cirrhosis, and even hepatocellular carcinoma regardless of etiologies including alcohol- or obesity-related and others. The frequency of PNPLA3(148M) variant ranges from 17% in African Americans, 23% in European Americans, to 49% in Hispanics in the Dallas Heart Study. Due to high prevalence of obesity and alcohol consumption in modern societies, the PNPLA3(148M) gene variant and environment interaction poses a serious concern for public health, especially chronic liver diseases including alcohol-related liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). Therefore, PNPLA3(148M) variant is a potential therapeutic target for chronic liver disease in the rs738409 allele carriers. Currently, there is no approved drug specifically targeting the PNPLA3(148M) variant yet. With additional mechanistic studies, novel therapeutic strategies are expected to be developed for the treatment of the PNPLA3(148M) variant-associated chronic liver diseases in the near future.
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Affiliation(s)
- Xiaocheng Charlie Dong
- Center for Diabetes and Metabolic Diseases, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
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64
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Sanaki T, Wakabayashi M, Yoshioka T, Yoshida R, Shishido T, Hall WW, Sawa H, Sato A. Inhibition of dengue virus infection by 1-stearoyl-2-arachidonoyl-phosphatidylinositol in vitro. FASEB J 2019; 33:13866-13881. [PMID: 31638831 DOI: 10.1096/fj.201901095rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Dengue fever is an acute febrile infectious disease caused by dengue virus (DENV). Despite the significant public health concerns posed by DENV, there are currently no effective anti-DENV therapeutic agents. To develop such drugs, a better understanding of the detailed mechanisms of DENV infection is needed. Both lipid metabolism and lipid synthesis are activated in DENV-infected cells, so we used lipid screening to identify potential antiviral lipid molecules. We identified 1-stearoyl-2-arachidonoyl-phosphatidylinositol (SAPI), which is the most abundant endogenous phosphatidylinositol (PI) molecular species, as an anti-DENV lipid molecule. SAPI suppressed the cytopathic effects induced by DENV2 infection as well as the replication of all DENV serotypes without inhibiting the entry of DENV2 into host cells. However, no other PI molecular species or PI metabolites, including lysophosphatidylinositols and phosphoinositides, displayed anti-DENV2 activity. Furthermore, SAPI suppressed the production of DENV2 infection-induced cytokines and chemokines, including C-C motif chemokine ligand (CCL)5, CCL20, C-X-C chemokine ligand 8, IL-6, and IFN-β. SAPI also suppressed the TNF-α production induced by LPS stimulation in macrophage cells differentiated from THP-1 cells. Our results demonstrated that SAPI is an endogenous inhibitor of DENV and modulated inflammatory responses in DENV2-infected cells, at least in part via TLR 4.-Sanaki, T., Wakabayashi, M., Yoshioka, T., Yoshida, R., Shishido, T., Hall, W. W., Sawa, H., Sato, A. Inhibition of dengue virus infection by 1-stearoyl-2-arachidonoyl-phosphatidylinositol in vitro.
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Affiliation(s)
- Takao Sanaki
- Drug Discovery and Disease Research Laboratory, Osaka, Japan.,Division of Anti-Virus Drug Research, Hokkaido University, Sapporo, Japan
| | - Masato Wakabayashi
- Biomarker Research and Development Department, Shionogi and Company, Limited, Osaka, Japan
| | - Takeshi Yoshioka
- Biomarker Research and Development Department, Shionogi and Company, Limited, Osaka, Japan
| | - Ryu Yoshida
- Drug Discovery and Disease Research Laboratory, Osaka, Japan
| | - Takao Shishido
- Drug Discovery and Disease Research Laboratory, Osaka, Japan
| | - William W Hall
- Global Institution for Collaborative Research and Education (Gi-CoRE), Hokkaido University, Sapporo, Japan.,Global Virus Network, Baltimore, Maryland, USA; and.,Center for Research in Infectious Diseases, University College of Dublin, Dublin, Ireland
| | - Hirofumi Sawa
- Global Institution for Collaborative Research and Education (Gi-CoRE), Hokkaido University, Sapporo, Japan.,Global Virus Network, Baltimore, Maryland, USA; and.,Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Akihiko Sato
- Drug Discovery and Disease Research Laboratory, Osaka, Japan.,Division of Anti-Virus Drug Research, Hokkaido University, Sapporo, Japan
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65
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Helsley RN, Varadharajan V, Brown AL, Gromovsky AD, Schugar RC, Ramachandiran I, Fung K, Kabbany MN, Banerjee R, Neumann CK, Finney C, Pathak P, Orabi D, Osborn LJ, Massey W, Zhang R, Kadam A, Sansbury BE, Pan C, Sacks J, Lee RG, Crooke RM, Graham MJ, Lemieux ME, Gogonea V, Kirwan JP, Allende DS, Civelek M, Fox PL, Rudel LL, Lusis AJ, Spite M, Brown JM. Obesity-linked suppression of membrane-bound O-acyltransferase 7 (MBOAT7) drives non-alcoholic fatty liver disease. eLife 2019; 8:e49882. [PMID: 31621579 PMCID: PMC6850774 DOI: 10.7554/elife.49882] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/11/2019] [Indexed: 12/14/2022] Open
Abstract
Recent studies have identified a genetic variant rs641738 near two genes encoding membrane bound O-acyltransferase domain-containing 7 (MBOAT7) and transmembrane channel-like 4 (TMC4) that associate with increased risk of non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), alcohol-related cirrhosis, and liver fibrosis in those infected with viral hepatitis (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017). Based on hepatic expression quantitative trait loci analysis, it has been suggested that MBOAT7 loss of function promotes liver disease progression (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017), but this has never been formally tested. Here we show that Mboat7 loss, but not Tmc4, in mice is sufficient to promote the progression of NAFLD in the setting of high fat diet. Mboat7 loss of function is associated with accumulation of its substrate lysophosphatidylinositol (LPI) lipids, and direct administration of LPI promotes hepatic inflammatory and fibrotic transcriptional changes in an Mboat7-dependent manner. These studies reveal a novel role for MBOAT7-driven acylation of LPI lipids in suppressing the progression of NAFLD.
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Affiliation(s)
- Robert N Helsley
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
- Department of Internal MedicineUniversity of CincinnatiCincinnatiUnited States
| | | | - Amanda L Brown
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Anthony D Gromovsky
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Rebecca C Schugar
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Iyappan Ramachandiran
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Kevin Fung
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | | | - Rakhee Banerjee
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Chase K Neumann
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Chelsea Finney
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Preeti Pathak
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Danny Orabi
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Lucas J Osborn
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - William Massey
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Renliang Zhang
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Anagha Kadam
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Brian E Sansbury
- Center for Experimental Therapeutics & Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonUnited States
| | - Calvin Pan
- Department of MedicineUniversity of California, Los AngelesLos AngelesUnited States
- Department of MicrobiologyUniversity of California, Los AngelesLos AngelesUnited States
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
| | - Jessica Sacks
- Department of PathobiologyCleveland ClinicClevelandUnited States
| | - Richard G Lee
- Cardiovascular Group, Antisense Drug DiscoveryIonis Pharmaceuticals, IncCarlsbadUnited States
| | - Rosanne M Crooke
- Cardiovascular Group, Antisense Drug DiscoveryIonis Pharmaceuticals, IncCarlsbadUnited States
| | - Mark J Graham
- Cardiovascular Group, Antisense Drug DiscoveryIonis Pharmaceuticals, IncCarlsbadUnited States
| | | | - Valentin Gogonea
- Department of ChemistryCleveland State UniversityClevelandUnited States
| | - John P Kirwan
- Department of PathobiologyCleveland ClinicClevelandUnited States
| | - Daniela S Allende
- Department of Anatomical PathologyCleveland ClinicClevelandUnited States
| | - Mete Civelek
- Department of Biomedical EngineeringUniversity of VirginiaCharlottesvilleUnited States
| | - Paul L Fox
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
| | - Lawrence L Rudel
- Department of Pathology, Section on Lipid SciencesWake Forest University School of MedicineWinston-SalemUnited States
| | - Aldons J Lusis
- Department of MedicineUniversity of California, Los AngelesLos AngelesUnited States
- Department of MicrobiologyUniversity of California, Los AngelesLos AngelesUnited States
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
| | - Matthew Spite
- Center for Experimental Therapeutics & Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonUnited States
| | - J Mark Brown
- Department of Cardiovascular and Metabolic SciencesCleveland ClinicClevelandUnited States
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66
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Jacher JE, Roy N, Ghaziuddin M, Innis JW. Expanding the phenotypic spectrum of MBOAT7-related intellectual disability. Am J Med Genet B Neuropsychiatr Genet 2019; 180:483-487. [PMID: 31282596 DOI: 10.1002/ajmg.b.32749] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 03/29/2019] [Accepted: 06/08/2019] [Indexed: 12/14/2022]
Abstract
MBOAT7 gene pathogenic variants are a newly discovered and rare cause for intellectual disability, autism spectrum disorder (ASD), seizures, truncal hypotonia, appendicular hypertonia, and below average head sizes (ranging from -1 to -3 standard deviations). There have been only 16 individuals previously reported who have MBOAT7-related intellectual disability, all of whom were younger than 10 years old and from consanguineous relationships. Thus, there is a lack of phenotypic information for adolescent and adult individuals with this disorder. Medical genetics and psychiatric evaluations in a 14-year-old female patient with a history of global developmental delay, intellectual disability, overgrowth with macrocephaly, metrorrhagia, seizures, basal ganglia hyperintensities, nystagmus, strabismus with amblyopia, ASD, anxiety, attention deficit hyperactivity disorder (ADHD), aggressive outbursts, and hyperphagia included a karyotype, methylation polymerase chain reaction for Prader-Willi/Angelman syndrome, chromosome microarray, and whole exome sequencing (WES), ADOS2, and ADI-R. WES identified a homozygous, likely pathogenic variant in the MBOAT7 gene (c.855-2A>G). This is the oldest known patient with MBOAT7-related intellectual disability, whose unique features compared with previously described individuals include overgrowth with macrocephaly, metrorrhagia, ophthalmological abnormalities, basal ganglia hyperintensities, unspecified anxiety disorder, and ADHD; combined type; and hyperphagia with the absence of appendicular hypertonia and cortical atrophy. More individuals need to be identified in order to delineate the full clinical spectrum of this disorder.
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Affiliation(s)
- Joseph E Jacher
- Department of Pediatrics and Communicable Diseases, Division of Pediatric Genetics, Metabolism and Genomic Medicine, University of Michigan, Ann Arbor, Michigan
| | - Nikita Roy
- Psychiatry, University of Michigan, Ann Arbor, Michigan
| | | | - Jeffrey W Innis
- Department of Pediatrics and Communicable Diseases, Division of Pediatric Genetics, Metabolism and Genomic Medicine, University of Michigan, Ann Arbor, Michigan.,Human Genetics, University of Michigan, Ann Arbor, Michigan.,Internal Medicine, University of Michigan, Ann Arbor, Michigan
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67
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Volpatti JR, Al-Maawali A, Smith L, Al-Hashim A, Brill JA, Dowling JJ. The expanding spectrum of neurological disorders of phosphoinositide metabolism. Dis Model Mech 2019; 12:12/8/dmm038174. [PMID: 31413155 PMCID: PMC6737944 DOI: 10.1242/dmm.038174] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Phosphoinositides (PIPs) are a ubiquitous group of seven low-abundance phospholipids that play a crucial role in defining localized membrane properties and that regulate myriad cellular processes, including cytoskeletal remodeling, cell signaling cascades, ion channel activity and membrane traffic. PIP homeostasis is tightly regulated by numerous inositol kinases and phosphatases, which phosphorylate and dephosphorylate distinct PIP species. The importance of these phospholipids, and of the enzymes that regulate them, is increasingly being recognized, with the identification of human neurological disorders that are caused by mutations in PIP-modulating enzymes. Genetic disorders of PIP metabolism include forms of epilepsy, neurodegenerative disease, brain malformation syndromes, peripheral neuropathy and congenital myopathy. In this Review, we provide an overview of PIP function and regulation, delineate the disorders associated with mutations in genes that modulate or utilize PIPs, and discuss what is understood about gene function and disease pathogenesis as established through animal models of these diseases. Summary: This Review highlights the intersection between phosphoinositides and the enzymes that regulate their metabolism, which together are crucial regulators of myriad cellular processes and neurological disorders.
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Affiliation(s)
- Jonathan R Volpatti
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Almundher Al-Maawali
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat 123, Oman
| | - Lindsay Smith
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Aqeela Al-Hashim
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Neuroscience, King Fahad Medical City, Riyadh 11525, Saudi Arabia
| | - Julie A Brill
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Program in Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - James J Dowling
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada .,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
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68
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Blunsom NJ, Gomez-Espinosa E, Ashlin TG, Cockcroft S. Sustained phospholipase C stimulation of H9c2 cardiomyoblasts by vasopressin induces an increase in CDP-diacylglycerol synthase 1 (CDS1) through protein kinase C and cFos. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1072-1082. [PMID: 30862571 PMCID: PMC6495107 DOI: 10.1016/j.bbalip.2019.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/28/2019] [Accepted: 03/06/2019] [Indexed: 01/18/2023]
Abstract
Chronic stimulation (24 h) with vasopressin leads to hypertrophy in H9c2 cardiomyoblasts and this is accompanied by continuous activation of phospholipase C. Consequently, vasopressin stimulation leads to a depletion of phosphatidylinositol levels. The substrate for phospholipase C is phosphatidylinositol (4, 5) bisphosphate (PIP2) and resynthesis of phosphatidylinositol and its subsequent phosphorylation maintains the supply of PIP2. The resynthesis of PI requires the conversion of phosphatidic acid to CDP-diacylglycerol catalysed by CDP-diacylglycerol synthase (CDS) enzymes. To examine whether the resynthesis of PI is regulated by vasopressin stimulation, we focussed on the CDS enzymes. Three CDS enzymes are present in mammalian cells: CDS1 and CDS2 are integral membrane proteins localised at the endoplasmic reticulum and TAMM41 is a peripheral protein localised in the mitochondria. Vasopressin selectively stimulates an increase CDS1 mRNA that is dependent on protein kinase C, and can be inhibited by the AP-1 inhibitor, T-5224. Vasopressin also stimulates an increase in cFos protein which is inhibited by a protein kinase C inhibitor. We conclude that vasopressin stimulates CDS1 mRNA through phospholipase C, protein kinase C and cFos and provides a potential mechanism for maintenance of phosphatidylinositol levels during long-term phospholipase C signalling.
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Affiliation(s)
- Nicholas J Blunsom
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Evelyn Gomez-Espinosa
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Tim G Ashlin
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Shamshad Cockcroft
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK.
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69
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Metabolic modulation predicts heart failure tests performance. PLoS One 2019; 14:e0218153. [PMID: 31220103 PMCID: PMC6586291 DOI: 10.1371/journal.pone.0218153] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 05/27/2019] [Indexed: 12/19/2022] Open
Abstract
The metabolic changes that accompany changes in Cardiopulmonary testing (CPET) and heart failure biomarkers (HFbio) are not well known. We undertook metabolomic and lipidomic phenotyping of a cohort of heart failure (HF) patients and utilized Multiple Regression Analysis (MRA) to identify associations to CPET and HFBio test performance (peak oxygen consumption (Peak VO2), oxygen uptake efficiency slope (OUES), exercise duration, and minute ventilation-carbon dioxide production slope (VE/VCO2 slope), as well as the established HF biomarkers of inflammation C-reactive protein (CRP), beta-galactoside-binding protein (galectin-3), and N-terminal prohormone of brain natriuretic peptide (NT-proBNP)). A cohort of 49 patients with a left ventricular ejection fraction < 50%, predominantly males African American, presenting a high frequency of diabetes, hyperlipidemia, and hypertension were used in the study. MRA revealed that metabolic models for VE/VCO2 and Peak VO2 were the most fitted models, and the highest predictors’ coefficients were from Acylcarnitine C18:2, palmitic acid, citric acid, asparagine, and 3-hydroxybutiric acid. Metabolic Pathway Analysis (MetPA) used predictors to identify the most relevant metabolic pathways associated to the study, aminoacyl-tRNA and amino acid biosynthesis, amino acid metabolism, nitrogen metabolism, pantothenate and CoA biosynthesis, sphingolipid and glycerolipid metabolism, fatty acid biosynthesis, glutathione metabolism, and pentose phosphate pathway (PPP). Metabolite Set Enrichment Analysis (MSEA) found associations of our findings with pre-existing biological knowledge from studies of human plasma metabolism as brain dysfunction and enzyme deficiencies associated with lactic acidosis. Our results indicate a profile of oxidative stress, lactic acidosis, and metabolic syndrome coupled with mitochondria dysfunction in patients with HF tests poor performance. The insights resulting from this study coincides with what has previously been discussed in existing literature thereby supporting the validity of our findings while at the same time characterizing the metabolic underpinning of CPET and HFBio.
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Blunsom NJ, Cockcroft S. Phosphatidylinositol synthesis at the endoplasmic reticulum. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158471. [PMID: 31173893 DOI: 10.1016/j.bbalip.2019.05.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/21/2019] [Accepted: 05/23/2019] [Indexed: 12/23/2022]
Abstract
Phosphatidylinositol (PI) is a minor phospholipid with a characteristic fatty acid profile; it is highly enriched in stearic acid at the sn-1 position and arachidonic acid at the sn-2 position. PI is phosphorylated into seven specific derivatives, and individual species are involved in a vast array of cellular functions including signalling, membrane traffic, ion channel regulation and actin dynamics. De novo PI synthesis takes place at the endoplasmic reticulum where phosphatidic acid (PA) is converted to PI in two enzymatic steps. PA is also produced at the plasma membrane during phospholipase C signalling, where hydrolysis of phosphatidylinositol (4,5) bisphosphate (PI(4,5)P2) leads to the production of diacylglycerol which is rapidly phosphorylated to PA. This PA is transferred to the ER to be also recycled back to PI. For the synthesis of PI, CDP-diacylglycerol synthase (CDS) converts PA to the intermediate, CDP-DG, which is then used by PI synthase to make PI. The de novo synthesised PI undergoes remodelling to acquire its characteristic fatty acid profile, which is altered in p53-mutated cancer cells. In mammals, there are two CDS enzymes at the ER, CDS1 and CDS2. In this review, we summarise the de novo synthesis of PI at the ER and the enzymes involved in its subsequent remodelling to acquire its characteristic acyl chains. We discuss how CDS, the rate limiting enzymes in PI synthesis are regulated by different mechanisms. During phospholipase C signalling, the CDS1 enzyme is specifically upregulated by cFos via protein kinase C.
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Affiliation(s)
- Nicholas J Blunsom
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Shamshad Cockcroft
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK.
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71
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Differential lipid composition and regulation along the hippocampal longitudinal axis. Transl Psychiatry 2019; 9:144. [PMID: 31028243 PMCID: PMC6486574 DOI: 10.1038/s41398-019-0478-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 04/02/2019] [Indexed: 01/16/2023] Open
Abstract
Lipids are major constituents of the brain largely implicated in physiological and pathological processes. The hippocampus is a complex brain structure involved in learning, memory and emotional responses, and its functioning is also affected in various disorders. Despite conserved intrinsic circuitry, behavioral and anatomical studies suggest the existence of a structural and functional gradient along the hippocampal longitudinal axis. Here, we used an unbiased mass spectrometry approach to characterize the lipid composition of distinct hippocampal subregions. In addition, we evaluated the susceptibility of each area to lipid modulation by corticosterone (CORT), an important mediator of the effects of stress. We confirmed a great similarity between hippocampal subregions relatively to other brain areas. Moreover, we observed a continuous molecular gradient along the longitudinal axis of the hippocampus, with the dorsal and ventral extremities differing significantly from each other, particularly in the relative abundance of sphingolipids and phospholipids. Also, whereas chronic CORT exposure led to remodeling of triacylglycerol and phosphatidylinositol species in both hippocampal poles, our study suggests that the ventral hippocampus is more sensitive to CORT-induced changes, with regional modulation of ceramide, dihydrosphingomyelin and phosphatidic acid. Thus, our results confirm a multipartite molecular view of dorsal-ventral hippocampal axis and emphasize lipid metabolites as candidate effectors of glucocorticoid signaling, mediating regional susceptibility to neurological disorders associated with stress.
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72
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Takemasu S, Ito M, Morioka S, Nigorikawa K, Kofuji S, Takasuga S, Eguchi S, Nakanishi H, Matsuoka I, Sasaki J, Sasaki T, Hazeki K. Lysophosphatidylinositol-acyltransferase-1 is involved in cytosolic Ca 2+ oscillations in macrophages. Genes Cells 2019; 24:366-376. [PMID: 30851234 DOI: 10.1111/gtc.12681] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/18/2022]
Abstract
Lysophosphatidylinositol-acyltransferase-1 (LPIAT1) specifically catalyzes the transfer of arachidonoyl-CoA to lysophosphoinositides. LPIAT-/- mice have been shown to have severe defects in the brain and liver; however, the exact molecular mechanisms behind these conditions are not well understood. As immune cells have been implicated in liver inflammation based on disfunction of LPIAT1, we generated Raw264.7 macrophages deficient in LPIAT1, using shRNA and CRISPR/Cas9. The amount of C38:4 species in phosphoinositides, especially in PtdInsP2 , was remarkably decreased in these cells. Unlike in wild-type cells, LPIAT1-deficient cells showed prolonged oscillations of intracellular Ca2+ upon UDP stimulation, which is known to activate phospholipase Cβ through the Gq-coupled P2Y6 receptor, even in the absence of extracellular Ca2+ . It is speculated that the prolonged Ca2+ response may be relevant to the increased risk of liver inflammation induced by LPIAT1 disfunction.
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Affiliation(s)
- Shinya Takemasu
- Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Masaaki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Japan
| | - Shin Morioka
- Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Kiyomi Nigorikawa
- Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Satoshi Kofuji
- Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Shunsuke Takasuga
- Department of Pathology and Immunology, Akita University School of Medicine, Akita, Japan
| | - Satoshi Eguchi
- Department of Pathology and Immunology, Akita University School of Medicine, Akita, Japan
| | - Hiroki Nakanishi
- Department of Pathology and Immunology, Akita University School of Medicine, Akita, Japan
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Japan
| | - Junko Sasaki
- Department of Pathology and Immunology, Akita University School of Medicine, Akita, Japan.,Department of Biochemical Pathophysiology, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Japan
| | - Takehiko Sasaki
- Department of Pathology and Immunology, Akita University School of Medicine, Akita, Japan.,Department of Biochemical Pathophysiology, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Japan
| | - Kaoru Hazeki
- Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
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73
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Caddeo A, Jamialahmadi O, Solinas G, Pujia A, Mancina RM, Pingitore P, Romeo S. MBOAT7 is anchored to endomembranes by six transmembrane domains. J Struct Biol 2019; 206:349-360. [PMID: 30959108 DOI: 10.1016/j.jsb.2019.04.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 03/17/2019] [Accepted: 04/05/2019] [Indexed: 01/08/2023]
Abstract
Membrane bound O-acyltransferase domain- containing 7 (MBOAT7, also known as LPIAT1) is a protein involved in the acyl chain remodeling of phospholipids via the Lands' cycle. The MBOAT7 is a susceptibility risk genetic locus for non-alcoholic fatty liver disease (NAFLD) and mental retardation. Although it has been shown that MBOAT7 is associated to membranes, the MBOAT7 topology remains unknown. To solve the topological organization of MBOAT7, we performed: A) solubilization of the total membrane fraction of cells overexpressing the recombinant MBOAT7-V5, which revealed MBOAT7 is an integral protein strongly attached to endomembranes; B) in silico analysis by using 22 computational methods, which predicted the number and localization of transmembrane domains of MBOAT7 with a range between 5 and 12; C) in vitro analysis of living cells transfected with GFP-tagged MBOAT7 full length and truncated forms, using a combination of Western Blotting, co-immunofluorescence and Fluorescence Protease Protection (FPP) assay; D) in vitro analysis of living cells transfected with FLAG-tagged MBOAT7 full length forms, using a combination of Western Blotting, selective membrane permeabilization followed by indirect immunofluorescence. All together, these data revealed that MBOAT7 is a multispanning transmembrane protein with six transmembrane domains. Based on our model, the predicted catalytic dyad of the protein, composed of the conserved asparagine in position 321 (Asn-321) and the preserved histidine in position 356 (His-356), has a lumenal localization. These data are compatible with the role of MBOAT7 in remodeling the acyl chain composition of endomembranes.
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Affiliation(s)
- Andrea Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Oveis Jamialahmadi
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden; Biotechnology Group, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
| | - Giovanni Solinas
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Arturo Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | | | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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74
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Murphy RC, Folco G. Lysophospholipid acyltransferases and leukotriene biosynthesis: intersection of the Lands cycle and the arachidonate PI cycle. J Lipid Res 2019; 60:219-226. [PMID: 30606731 DOI: 10.1194/jlr.s091371] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/03/2019] [Indexed: 12/18/2022] Open
Abstract
Leukotrienes (LTs) are autacoids derived from the precursor arachidonic acid (AA) via the action of five-lipoxygenase (5-LO). When inflammatory cells are activated, 5-LO translocates to the nuclear membrane to initiate oxygenation of AA released by cytosolic phospholipase A2 (cPLA2) into leukotriene A4 (LTA4). LTA4 can also be exported from an activated donor cell into an acceptor cell by the process of transcellular biosynthesis. When thimerosal is added to cells, the level of free AA increases by inhibition of lysophospholipid acyltransferases of the Lands pathway of phospholipid remodeling. Another arachidonate phospholipid cycle involves phosphatidylinositol (PI) in the plasma membrane that undoubtedly intersects with the Lands pathway of phospholipid remodeling. The highest abundance of PI occurs between the ER and the plasma membrane and is probably a result of the importance of the PI signaling cascade in cellular biochemistry. Because transport proteins mediate the rapid intracellular movement of phospholipids, largely as result of physical membrane contact, 5-LO-dependent production of LTA4 could be mediated by the disappearance of free AA from the nuclear membrane, transfer to the ER for Lands cycle reesterification into PI, and population of PI(18:0/20:4) for cell membrane signaling.
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Affiliation(s)
- Robert C Murphy
- Department of Pharmacology, University of Colorado Denver, Aurora, CO 80045
| | - Giancarlo Folco
- Department of Pharmacology, University of Colorado Denver, Aurora, CO 80045
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75
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Mizukami T, Ikeda K, Shimanaka Y, Korogi K, Zhou C, Takase H, Tsuiji H, Kono N, Kohno T, Arai H, Arita M, Hattori M. Reelin deficiency leads to aberrant lipid composition in mouse brain. Biochem Biophys Res Commun 2018; 505:81-86. [PMID: 30241938 DOI: 10.1016/j.bbrc.2018.09.089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 09/13/2018] [Indexed: 01/14/2023]
Abstract
Reelin is a secreted protein essential for the development and function of the mammalian brain. The receptors for Reelin, apolipoprotein E receptor 2 and very low-density lipoprotein receptor, belong to the low-density lipoprotein receptor family, but it is not known whether Reelin is involved in the brain lipid metabolism. In the present study, we performed lipidomic analysis of the cerebral cortex of wild-type and Reelin-deficient (reeler) mice, and found that reeler mice exhibited several compositional changes in phospholipids. First, the ratio of phospholipids containing one saturated fatty acid (FA) and one docosahexaenoic acid (DHA) or arachidonic acid (ARA) decreased. Secondly, the ratio of phospholipids containing one monounsaturated FA (MUFA) and one DHA or ARA increased. Thirdly, the ratio of phospholipids containing 5,8,11-eicosatrienoic acid, or Mead acid (MA), increased. Finally, the expression of stearoyl-CoA desaturase-1 (SCD-1) increased. As the increase of MA is seen as an index of polyunsaturated FA (PUFA) deficiency, and the expression of SCD-1 is suppressed by PUFA, these results strongly suggest that the loss of Reelin leads to PUFA deficiency. Hence, MUFA and MA are synthesized in response to this deficiency, in part by inducing SCD-1 expression. This is the first report of changes of FA composition in the reeler mouse brain and provides a basis for further investigating the new role of Reelin in the development and function of the brain.
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Affiliation(s)
- Tomoharu Mizukami
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan
| | - Kazutaka Ikeda
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, 230-0045, Japan; AMED-PRIME, Japan Agency for Medical Research and Development, Tokyo, 100-0004, Japan
| | - Yuta Shimanaka
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Katsunari Korogi
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan
| | - Chunyu Zhou
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan
| | - Hiroshi Takase
- Core Laboratory, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Aichi, 467-8601, Japan
| | - Hitomi Tsuiji
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Takao Kohno
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan
| | - Hiroyuki Arai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Makoto Arita
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, 230-0045, Japan; Division of Physiological Chemistry and Metabolism, Keio University Faculty of Pharmacy, Tokyo, 180-8512, Japan; Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa, 230-0045, Japan
| | - Mitsuharu Hattori
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, 467-8603, Japan.
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Inloes JM, Jing H, Cravatt BF. The Spastic Paraplegia-Associated Phospholipase DDHD1 Is a Primary Brain Phosphatidylinositol Lipase. Biochemistry 2018; 57:5759-5767. [PMID: 30221923 PMCID: PMC6237197 DOI: 10.1021/acs.biochem.8b00810] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Deleterious mutations in the serine hydrolase DDHD domain containing 1 (DDHD1) cause the SPG28 subtype of the neurological disease hereditary spastic paraplegia (HSP), which is characterized by axonal neuropathy and gait impairments. DDHD1 has been shown to display PLA1-type phospholipase activity with a preference for phosphatidic acid. However, the endogenous lipid pathways regulated by DDHD1 in vivo remain poorly understood. Here we use a combination of untargeted and targeted metabolomics to compare the lipid content of brain tissue from DDHD1+/+ and DDHD1-/- mice, revealing that DDHD1 inactivation causes a substantial decrease in the level of polyunsaturated lysophosphatidylinositol (LPI) lipids and a corresponding increase in the level of phosphatidylinositol (PI) lipids. Levels of other phospholipids were mostly unchanged, with the exception of decreases in the levels of select polyunsaturated lysophosphatidylserine (LPS) and lysophosphatidylcholine lipids and a striking remodeling of PI phosphates (e.g., PIP and PIP2) in DDHD1-/- brain tissue. Biochemical assays confirmed that DDHD1 hydrolyzes PI/PS to LPI/LPS with sn-1 selectivity and accounts for a substantial fraction of the PI/PS lipase activity in mouse brain tissue. These data indicate that DDHD1 is a principal regulator of bioactive LPI and other lysophospholipids, as well as PI phosphates, in the mammalian nervous system, pointing to a potential role for these lipid pathways in HSP.
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Affiliation(s)
- Jordon M. Inloes
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Hui Jing
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Benjamin F. Cravatt
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
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Aberrant cardiolipin metabolism is associated with cognitive deficiency and hippocampal alteration in tafazzin knockdown mice. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3353-3367. [PMID: 30055293 DOI: 10.1016/j.bbadis.2018.07.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 06/14/2018] [Accepted: 07/19/2018] [Indexed: 12/17/2022]
Abstract
Cardiolipin (CL) is a key mitochondrial phospholipid essential for mitochondrial energy production. CL is remodeled from monolysocardiolipin (MLCL) by the enzyme tafazzin (TAZ). Loss-of-function mutations in the gene which encodes TAZ results in a rare X-linked disorder called Barth Syndrome (BTHS). The mutated TAZ is unable to maintain the physiological CL:MLCL ratio, thus reducing CL levels and affecting mitochondrial function. BTHS is best known as a cardiac disease, but has been acknowledged as a multi-syndrome disorder, including cognitive deficits. Since reduced CL levels has also been reported in numerous neurodegenerative disorders, we examined how TAZ-deficiency impacts cognitive abilities, brain mitochondrial respiration and the function of hippocampal neurons and glia in TAZ knockdown (TAZ kd) mice. We have identified for the first time the profile of changes that occur in brain phospholipid content and composition of TAZ kd mice. The brain of TAZ kd mice exhibited reduced TAZ protein expression, reduced total CL levels and a 19-fold accumulation of MLCL compared to wild-type littermate controls. TAZ kd brain exhibited a markedly distinct profile of CL and MLCL molecular species. In mitochondria, the activity of complex I was significantly elevated in the monomeric and supercomplex forms with TAZ-deficiency. This corresponded with elevated mitochondrial state I respiration and attenuated spare capacity. Furthermore, the production of reactive oxygen species was significantly elevated in TAZ kd brain mitochondria. While motor function remained normal in TAZ kd mice, they showed significant memory deficiency based on novel object recognition test. These results correlated with reduced synaptophysin protein levels and derangement of the neuronal CA1 layer in hippocampus. Finally, TAZ kd mice had elevated activation of brain immune cells, microglia compared to littermate controls. Collectively, our findings demonstrate that TAZ-mediated remodeling of CL contributes significantly to the expansive distribution of CL molecular species in the brain, plays a key role in mitochondria respiratory activity, maintains normal cognitive function, and identifies the hippocampus as a potential therapeutic target for BTHS.
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Do inositol supplements enhance phosphatidylinositol supply and thus support endoplasmic reticulum function? Br J Nutr 2018; 120:301-316. [PMID: 29859544 DOI: 10.1017/s0007114518000946] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review attempts to explain why consuming extra myoinositol (Ins), an essential component of membrane phospholipids, is often beneficial for patients with conditions characterised by insulin resistance, non-alcoholic fatty liver disease and endoplasmic reticulum (ER) stress. For decades we assumed that most human diets provide an adequate Ins supply, but newer evidence suggests that increasing Ins intake ameliorates several disorders, including polycystic ovary syndrome, gestational diabetes, metabolic syndrome, poor sperm development and retinopathy of prematurity. Proposed explanations often suggest functional enhancement of minor facets of Ins Biology such as insulin signalling through putative inositol-containing 'mediators', but offer no explanation for this selectivity. It is more likely that eating extra Ins corrects a deficiency of an abundant Ins-containing cell constituent, probably phosphatidylinositol (PtdIns). Much of a cell's PtdIns is in ER membranes, and an increase in ER membrane synthesis, enhancing the ER's functional capacity, is often an important part of cell responses to ER stress. This review: (a) reinterprets historical information on Ins deficiency as describing a set of events involving a failure of cells adequately to adapt to ER stress; (b) proposes that in the conditions that respond to dietary Ins there is an overstretching of Ins reserves that limits the stressed ER's ability to make the 'extra' PtdIns needed for ER membrane expansion; and (c) suggests that eating Ins supplements increases the Ins supply to Ins-deficient and ER-stressed cells, allowing them to make more PtdIns and to expand the ER membrane system and sustain ER functions.
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Alhouayek M, Masquelier J, Muccioli GG. Lysophosphatidylinositols, from Cell Membrane Constituents to GPR55 Ligands. Trends Pharmacol Sci 2018; 39:586-604. [PMID: 29588059 DOI: 10.1016/j.tips.2018.02.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 02/20/2018] [Accepted: 02/28/2018] [Indexed: 12/25/2022]
Abstract
Lysophosphatidylinositols (LPIs) are membrane constituents that alter the properties of said membranes. However, recent data showing that the once orphan receptor, GPR55, can act as a receptor for LPIs has sparked a renewed interest in LPIs as bioactive lipids. As evidence supporting the importance of LPIs and/or GPR55 is continuously accumulating and because LPI levels are altered in a number of pathologies such as obesity and cancer, the coming years should bring new, exciting discoveries to this field. In this review, we discuss the recent work on LPIs and on their molecular target, the GPR55 receptor. First, we summarize the metabolism of LPIs before outlining the cellular pathways activated by GPR55. Then, we review the actions of LPIs and GPR55 that could have potential pharmacological or therapeutic applications in several pathophysiological settings, such as cancer, obesity, pain, and inflammation.
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Affiliation(s)
- Mireille Alhouayek
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium; These authors contributed equally to this work
| | - Julien Masquelier
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium; These authors contributed equally to this work
| | - Giulio G Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium.
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81
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Okuno T, Gijón MA, Zarini S, Martin SA, Barkley RM, Johnson CA, Ohba M, Yokomizo T, Murphy RC. Altered eicosanoid production and phospholipid remodeling during cell culture. J Lipid Res 2018; 59:542-549. [PMID: 29353239 DOI: 10.1194/jlr.m083030] [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: 12/28/2017] [Revised: 12/28/2017] [Indexed: 12/21/2022] Open
Abstract
The remodeling of PUFAs by the Lands cycle is responsible for the diversity of phospholipid molecular species found in cells. There have not been detailed studies of the alteration of phospholipid molecular species as a result of serum starvation or depletion of PUFAs that typically occurs during tissue culture. The time-dependent effect of cell culture on phospholipid molecular species in RAW 264.7 cells cultured for 24, 48, or 72 h was examined by lipidomic strategies. These cells were then stimulated to produce arachidonate metabolites derived from the cyclooxygenase pathway, thromboxane B2, PGE2, and PGD2, and the 5-lipoxygenase pathway, leukotriene (LT)B4, LTC4, and 5-HETE, which decreased with increasing time in culture. However, the 5-lipoxygenase metabolites of a 20:3 fatty acid, LTB3, all trans-LTB3, LTC3, and 5-hydroxyeicosatrienoic acid, time-dependently increased. Molecular species of arachidonate containing phospholipids were drastically remodeled during cell culture, with a new 20:3 acyl group being populated into phospholipids to replace increasingly scarce arachidonate. In addition, the amount of TNFα induced by lipopolysaccharide stimulation was significantly increased in the cells cultured for 72 h compared with 24 h, suggesting that the remodeling of PUFAs enhanced inflammatory response. These studies supported the rapid operation of the Lands cycle to maintain cell growth and viability by populating PUFA species; however, without sufficient n-6 fatty acids, 20:3 n-9 accumulated, resulting in altered lipid mediator biosynthesis and inflammatory response.
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Affiliation(s)
- Toshiaki Okuno
- Department of Biochemistry, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Miguel A Gijón
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
| | - Simona Zarini
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
| | - Sarah A Martin
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
| | - Robert M Barkley
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
| | - Christopher A Johnson
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
| | - Mai Ohba
- Department of Biochemistry, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Takehiko Yokomizo
- Department of Biochemistry, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Robert C Murphy
- Department of Pharmacology, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045
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82
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Ikedo T, Minami M, Kataoka H, Hayashi K, Nagata M, Fujikawa R, Yamazaki F, Setou M, Yokode M, Miyamoto S. Imaging mass spectroscopy delineates the thinned and thickened walls of intracranial aneurysms. Biochem Biophys Res Commun 2018; 495:332-338. [DOI: 10.1016/j.bbrc.2017.10.133] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Accepted: 10/25/2017] [Indexed: 12/22/2022]
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83
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Choy CH, Han BK, Botelho RJ. Phosphoinositide Diversity, Distribution, and Effector Function: Stepping Out of the Box. Bioessays 2017; 39. [PMID: 28977683 DOI: 10.1002/bies.201700121] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/31/2017] [Indexed: 12/26/2022]
Abstract
Phosphoinositides (PtdInsPs) modulate a plethora of functions including signal transduction and membrane trafficking. PtdInsPs are thought to consist of seven interconvertible species that localize to a specific organelle, to which they recruit a set of cognate effector proteins. Here, in reviewing the literature, we argue that this model needs revision. First, PtdInsPs can carry a variety of acyl chains, greatly boosting their molecular diversity. Second, PtdInsPs are more promiscuous in their localization than is usually acknowledged. Third, PtdInsP interconversion is likely achieved through kinase-phosphatase enzyme complexes that coordinate their activities and channel substrates without affecting bulk substrate population. Additionally, we contend that despite hundreds of PtdInsP effectors, our attention is biased toward few proteins. Lastly, we recognize that PtdInsPs can act to nucleate coincidence detection at the effector level, as in PDK1 and Akt. Overall, better integrated models of PtdInsP regulation and function are not only possible but needed.
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Affiliation(s)
- Christopher H Choy
- Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada M5B2K3.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada M5B2K3
| | - Bong-Kwan Han
- The Intelligent Synthetic Biology Center, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Roberto J Botelho
- Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada M5B2K3.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada M5B2K3
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84
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Liu AP, Botelho RJ, Antonescu CN. The big and intricate dreams of little organelles: Embracing complexity in the study of membrane traffic. Traffic 2017; 18:567-579. [DOI: 10.1111/tra.12497] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 05/30/2017] [Accepted: 05/30/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Allen P. Liu
- Department of Mechanical Engineering University of Michigan Ann Arbor Michigan
- Department of Biomedical Engineering University of Michigan Ann Arbor Michigan
- Cellular and Molecular Biology Program University of Michigan Ann Arbor Michigan
- Biophysics Program University of Michigan Ann Arbor Michigan
| | - Roberto J. Botelho
- The Graduate Program in Molecular Science and Department of Chemistry and Biology Ryerson University Toronto Canada
| | - Costin N. Antonescu
- The Graduate Program in Molecular Science and Department of Chemistry and Biology Ryerson University Toronto Canada
- Keenan Research Centre for Biomedical Science St. Michael's Hospital Toronto Canada
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85
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Topological organisation of the phosphatidylinositol 4,5-bisphosphate-phospholipase C resynthesis cycle: PITPs bridge the ER-PM gap. Biochem J 2017; 473:4289-4310. [PMID: 27888240 DOI: 10.1042/bcj20160514c] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 09/08/2016] [Accepted: 09/12/2016] [Indexed: 12/13/2022]
Abstract
Phospholipase C (PLC) is a receptor-regulated enzyme that hydrolyses phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) at the plasma membrane (PM) triggering three biochemical consequences, the generation of soluble inositol 1,4,5-trisphosphate (IP3), membrane-associated diacylglycerol (DG) and the consumption of PM PI(4,5)P2 Each of these three signals triggers multiple molecular processes impacting key cellular properties. The activation of PLC also triggers a sequence of biochemical reactions, collectively referred to as the PI(4,5)P2 cycle that culminates in the resynthesis of this lipid. The biochemical intermediates of this cycle and the enzymes that mediate these reactions are topologically distributed across two membrane compartments, the PM and the endoplasmic reticulum (ER). At the PM, the DG formed during PLC activation is rapidly converted into phosphatidic acid (PA) that needs to be transported to the ER where the machinery for its conversion into PI is localised. Conversely, PI from the ER needs to be rapidly transferred to the PM where it can be phosphorylated by lipid kinases to regenerate PI(4,5)P2 Thus, two lipid transport steps between membrane compartments through the cytosol are required for the replenishment of PI(4,5)P2 at the PM. Here, we review the topological constraints in the PI(4,5)P2 cycle and current understanding how these constraints are overcome during PLC signalling. In particular, we discuss the role of lipid transfer proteins in this process. Recent findings on the biochemical properties of a membrane-associated lipid transfer protein of the PITP family, PITPNM proteins (alternative name RdgBα/Nir proteins) that localise to membrane contact sites are discussed. Studies in both Drosophila and mammalian cells converge to provide a resolution to the conundrum of reciprocal transfer of PA and PI during PLC signalling.
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86
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Johansen A, Rosti RO, Musaev D, Sticca E, Harripaul R, Zaki M, Çağlayan AO, Azam M, Sultan T, Froukh T, Reis A, Popp B, Ahmed I, John P, Ayub M, Ben-Omran T, Vincent JB, Gleeson JG, Abou Jamra R. Mutations in MBOAT7, Encoding Lysophosphatidylinositol Acyltransferase I, Lead to Intellectual Disability Accompanied by Epilepsy and Autistic Features. Am J Hum Genet 2016; 99:912-916. [PMID: 27616480 DOI: 10.1016/j.ajhg.2016.07.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/25/2016] [Indexed: 10/21/2022] Open
Abstract
The risk of epilepsy among individuals with intellectual disability (ID) is approximately ten times that of the general population. From a cohort of >5,000 families affected by neurodevelopmental disorders, we identified six consanguineous families harboring homozygous inactivating variants in MBOAT7, encoding lysophosphatidylinositol acyltransferase (LPIAT1). Subjects presented with ID frequently accompanied by epilepsy and autistic features. LPIAT1 is a membrane-bound phospholipid-remodeling enzyme that transfers arachidonic acid (AA) to lysophosphatidylinositol to produce AA-containing phosphatidylinositol. This study suggests a role for AA-containing phosphatidylinositols in the development of ID accompanied by epilepsy and autistic features.
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87
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Hiraide T, Ikegami K, Sakaguchi T, Morita Y, Hayasaka T, Masaki N, Waki M, Sugiyama E, Shinriki S, Takeda M, Shibasaki Y, Miyazaki S, Kikuchi H, Okuyama H, Inoue M, Setou M, Konno H. Accumulation of arachidonic acid-containing phosphatidylinositol at the outer edge of colorectal cancer. Sci Rep 2016; 6:29935. [PMID: 27435310 PMCID: PMC4951683 DOI: 10.1038/srep29935] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 06/27/2016] [Indexed: 02/06/2023] Open
Abstract
Accumulating evidence indicates that cancer cells show specific alterations in phospholipid metabolism that contribute to tumour progression in several types of cancer, including colorectal cancer. Questions still remain as to what lipids characterize the outer edge of cancer tissues and whether those cancer outer edge-specific lipid compositions emerge autonomously in cancer cells. Cancer tissue-originated spheroids (CTOSs) that are composed of pure primary cancer cells have been developed. In this study, we aimed to seek out the cancer cell-autonomous acquisition of cancer outer edge-characterizing lipids in colorectal cancer by analysing phospholipids in CTOSs derived from colorectal cancer patients with matrix-assisted laser desorption/ionization (MALDI)-imaging mass spectrometry (IMS). A signal at m/z 885.5 in negative ion mode was detected specifically at the surface regions. The signal was identified as an arachidonic acid (AA)-containing phosphatidylinositol (PI), PI(18:0/20:4), by tandem mass spectrometry analysis. Quantitative analysis revealed that the amount of PI(18:0/20:4) in the surface region of CTOSs was two-fold higher than that in the medial region. Finally, PI(18:0/20:4) was enriched at the cancer cells/stromal interface in colorectal cancer patients. These data imply a possible importance of AA-containing PI for colorectal cancer progression, and suggest cells expressing AA-containing PI as potential targets for anti-cancer therapy.
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Affiliation(s)
- Takanori Hiraide
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Koji Ikegami
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,International Mass Imaging Center, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Takanori Sakaguchi
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Yoshifumi Morita
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Takahiro Hayasaka
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Noritaka Masaki
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,International Mass Imaging Center, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Michihiko Waki
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Eiji Sugiyama
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,International Mass Imaging Center, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Satoru Shinriki
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Makoto Takeda
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Yasushi Shibasaki
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Shinichiro Miyazaki
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Hirotoshi Kikuchi
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
| | - Hiroaki Okuyama
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Higashinari-ku, Osaka, Japan
| | - Masahiro Inoue
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Higashinari-ku, Osaka, Japan
| | - Mitsutoshi Setou
- Department of Cellular and Molecular Anatomy, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,International Mass Imaging Center, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,Preeminent Medical Photonics Education &Research Center, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan.,Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong SAR.,Division of Neural Systematics, National Institute for Physiological Sciences, Myodaiji, Okazaki, Japan.,Riken Center for Molecular Imaging Science, Chuo-ku, Kobe, Japan
| | - Hiroyuki Konno
- Second Department of Surgery, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Japan
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88
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Epand RM. Features of the Phosphatidylinositol Cycle and its Role in Signal Transduction. J Membr Biol 2016; 250:353-366. [PMID: 27278236 DOI: 10.1007/s00232-016-9909-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/26/2016] [Indexed: 01/03/2023]
Abstract
The phosphatidylinositol cycle (PI-cycle) has a central role in cell signaling. It is the major pathway for the synthesis of phosphatidylinositol and its phosphorylated forms. In addition, some lipid intermediates of the PI-cycle, including diacylglycerol and phosphatidic acid, are also important lipid signaling agents. The PI-cycle has some features that are important for the understanding of its role in the cell. As a cycle, the intermediates will be regenerated. The PI-cycle requires a large amount of metabolic energy. There are different steps of the cycle that occur in two different membranes, the plasma membrane and the endoplasmic reticulum. In order to complete the PI-cycle lipid must be transferred between the two membranes. The role of the Nir proteins in the process has recently been elucidated. The lipid intermediates of the PI-cycle are normally highly enriched with 1-stearoyl-2-arachidonoyl molecular species in mammals. This enrichment will be retained as long as the intermediates are segregated from other lipids of the cell. However, there is a significant fraction (>15 %) of lipids in the PI-cycle of normal cells that have other acyl chains. Phosphatidylinositol largely devoid of arachidonoyl chains are found in cancer cells. Phosphatidylinositol species with less unsaturation will not be as readily converted to phosphatidylinositol-3,4,5-trisphosphate, the lipid required for the activation of Akt with resulting effects on cell proliferation. Thus, the cyclical nature of the PI-cycle, its dependence on acyl chain composition and its requirement for lipid transfer between two membranes, explain many of the biological properties of this cycle.
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Affiliation(s)
- Richard M Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada.
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89
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Hadley KB, Ryan AS, Forsyth S, Gautier S, Salem N. The Essentiality of Arachidonic Acid in Infant Development. Nutrients 2016; 8:216. [PMID: 27077882 PMCID: PMC4848685 DOI: 10.3390/nu8040216] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/01/2016] [Accepted: 04/05/2016] [Indexed: 01/16/2023] Open
Abstract
Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health. These studies also demonstrate the importance of balancing the amounts of ARA and DHA as too much DHA may suppress the benefits provided by ARA. Both ARA and DHA have been added to infant formulas and follow-on formulas for more than two decades. The amounts and ratios of ARA and DHA needed in infant formula are discussed based on an in depth review of the available scientific evidence.
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Affiliation(s)
- Kevin B Hadley
- DSM Nutritional Products, 6480 Dobbin Road, Columbia, MD 21045, USA.
| | - Alan S Ryan
- Clinical Research Consulting, 9809 Halston Manor, Boynton Beach, FL 33473, USA.
| | - Stewart Forsyth
- School of Medicine, Dentistry & Nursing, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK.
| | - Sheila Gautier
- DSM Nutritional Products, 6480 Dobbin Road, Columbia, MD 21045, USA.
| | - Norman Salem
- DSM Nutritional Products, 6480 Dobbin Road, Columbia, MD 21045, USA.
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90
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Kimura T, Jennings W, Epand RM. Roles of specific lipid species in the cell and their molecular mechanism. Prog Lipid Res 2016; 62:75-92. [PMID: 26875545 DOI: 10.1016/j.plipres.2016.02.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/04/2016] [Accepted: 02/10/2016] [Indexed: 12/19/2022]
Abstract
Thousands of different molecular species of lipids are present within a single cell, being involved in modulating the basic processes of life. The vast number of different lipid species can be organized into a number of different lipid classes, which may be defined as a group of lipids with a common chemical structure, such as the headgroup, apart from the nature of the hydrocarbon chains. Each lipid class has unique biological roles. In some cases, a relatively small change in the headgroup chemical structure can result in a drastic change in function. Such phenomena are well documented, and largely understood in terms of specific interactions with proteins. In contrast, there are observations that the entire structural specificity of a lipid molecule, including the hydrocarbon chains, is required for biological activity through specific interactions with membrane proteins. Understanding of these phenomena represents a fundamental change in our thinking of the functions of lipids in biology. There are an increasing number of diverse examples of roles for specific lipids in cellular processes including: Signal transduction; trafficking; morphological changes; cell division. We are gaining knowledge and understanding of the underlying molecular mechanisms. They are of growing importance in both basic and applied sciences.
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Affiliation(s)
- Tomohiro Kimura
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
| | - William Jennings
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
| | - Richard M Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
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91
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Requirement of Phosphoinositides Containing Stearic Acid To Control Cell Polarity. Mol Cell Biol 2015; 36:765-80. [PMID: 26711260 DOI: 10.1128/mcb.00843-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 12/14/2015] [Indexed: 02/04/2023] Open
Abstract
Phosphoinositides (PIPs) are present in very small amounts but are essential for cell signaling, morphogenesis, and polarity. By mass spectrometry, we demonstrated that some PIPs with stearic acyl chains were strongly disturbed in a psi1Δ Saccharomyces cerevisiae yeast strain deficient in the specific incorporation of a stearoyl chain at the sn-1 position of phosphatidylinositol. The absence of PIPs containing stearic acid induced disturbances in intracellular trafficking, although the total amount of PIPs was not diminished. Changes in PIPs also induced alterations in the budding pattern and defects in actin cytoskeleton organization (cables and patches). Moreover, when the PSI1 gene was impaired, a high proportion of cells with bipolar cortical actin patches that occurred concomitantly with the bipolar localization of Cdc42p was specifically found among diploid cells. This bipolar cortical actin phenotype, never previously described, was also detected in a bud9Δ/bud9Δ strain. Very interestingly, overexpression of PSI1 reversed this phenotype.
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92
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Bradley RM, Marvyn PM, Aristizabal Henao JJ, Mardian EB, George S, Aucoin MG, Stark KD, Duncan RE. Acylglycerophosphate acyltransferase 4 (AGPAT4) is a mitochondrial lysophosphatidic acid acyltransferase that regulates brain phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol levels. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1566-76. [DOI: 10.1016/j.bbalip.2015.09.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/18/2015] [Accepted: 09/24/2015] [Indexed: 10/23/2022]
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93
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Anderson KE, Juvin V, Clark J, Stephens LR, Hawkins PT. Investigating the effect of arachidonate supplementation on the phosphoinositide content of MCF10a breast epithelial cells. Adv Biol Regul 2015; 62:18-24. [PMID: 26639089 PMCID: PMC5061326 DOI: 10.1016/j.jbior.2015.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/05/2015] [Indexed: 11/27/2022]
Abstract
Phosphoinositides in primary mammalian tissue are highly enriched in a stearoyl/arachidonyl (C38:4) diacylgycerol backbone. However, mammalian cells grown in culture typically contain more diverse molecular species of phosphoinositides, characterised by a reduction in arachidonyl content in the sn-2 position. We have analysed the phosphoinositide species in MCF10a cells grown in culture by mass spectrometry. Under either serum or serum starved conditions the most abundant species of PI, PIP, PIP2 and PIP3 had masses which corresponded to C36:2, C38:4, C38:3, C38:2 and C36:1 diacylglycerol backbones and the relative proportions of each molecular species were broadly similar between each phosphoinositide class (approx. 50%, 25%, 10%, 10% and 10% respectively, for the species listed above). Supplementing the culture medium with BSA-loaded arachidonic acid promoted a rapid increase in the proportion of the C38:4 species in all phosphoinositide classes (from approx. 25%-60% of total species within 24 h), but the total amount of all combined species for each class remained remarkably constant. Stimulation of cells, cultured in either normal or arachidonate-enriched conditions, with 2 ng/ml EGF for 90 s caused substantial activation of Class I PI3K and accumulation of PIP3. Despite the increased proportion of C38:4 PIP3 under the arachidonate-supplemented conditions, the total amount of all combined PIP3 species accumulating in response to EGF was the same, with or without arachidonate supplementation; there were however small but significant preferences for the conversion of some PIP2 species to PIP3, with the polyunsaturated C38:4 and C38:3 species being more favoured over other species. These results suggest the enzymes which interconvert phosphoinositides are able to act on several different molecular species and homoeostatic mechanisms are in place to deliver similar phosphoinositide pool sizes under quite different conditions of arachidonate availability. They also suggest enzymes regulating PIP3 levels downstream of growth factor stimulation (i.e. PI3Ks and PIP3-phosphatases) show some acyl selectivity and further work should be directed at assessing whether different acyl species of PIP3 exhibit differing signalling potential.
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Affiliation(s)
- Karen E Anderson
- Inositide Laboratory and Babraham Institute, Babraham Research Campus, Babraham, Cambridge, CB223AT, UK.
| | - Veronique Juvin
- Inositide Laboratory and Babraham Institute, Babraham Research Campus, Babraham, Cambridge, CB223AT, UK.
| | - Jonathan Clark
- Biological Chemistry Laboratory, Babraham Institute, Babraham Research Campus, Babraham, Cambridge CB223AT, UK.
| | - Len R Stephens
- Inositide Laboratory and Babraham Institute, Babraham Research Campus, Babraham, Cambridge, CB223AT, UK.
| | - Phillip T Hawkins
- Inositide Laboratory and Babraham Institute, Babraham Research Campus, Babraham, Cambridge, CB223AT, UK.
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94
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Hashidate-Yoshida T, Harayama T, Hishikawa D, Morimoto R, Hamano F, Tokuoka SM, Eto M, Tamura-Nakano M, Yanobu-Takanashi R, Mukumoto Y, Kiyonari H, Okamura T, Kita Y, Shindou H, Shimizu T. Fatty acid remodeling by LPCAT3 enriches arachidonate in phospholipid membranes and regulates triglyceride transport. eLife 2015; 4. [PMID: 25898003 PMCID: PMC4436788 DOI: 10.7554/elife.06328] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/19/2015] [Indexed: 12/22/2022] Open
Abstract
Polyunsaturated fatty acids (PUFAs) in phospholipids affect the physical properties of membranes, but it is unclear which biological processes are influenced by their regulation. For example, the functions of membrane arachidonate that are independent of a precursor role for eicosanoid synthesis remain largely unknown. Here, we show that the lack of lysophosphatidylcholine acyltransferase 3 (LPCAT3) leads to drastic reductions in membrane arachidonate levels, and that LPCAT3-deficient mice are neonatally lethal due to an extensive triacylglycerol (TG) accumulation and dysfunction in enterocytes. We found that high levels of PUFAs in membranes enable TGs to locally cluster in high density, and that this clustering promotes efficient TG transfer. We propose a model of local arachidonate enrichment by LPCAT3 to generate a distinct pool of TG in membranes, which is required for normal directionality of TG transfer and lipoprotein assembly in the liver and enterocytes. DOI:http://dx.doi.org/10.7554/eLife.06328.001 Membranes made of molecules called lipids surround every living cell and also form compartments inside the cell. There are hundreds of different lipid molecules that can be found in membranes. The amount of each type within the membrane can vary, which affects the flexibility and other physical properties of the membrane. One type of lipid found in membranes is called arachidonic acid. It is involved in cell communication and other processes, and is required for young animals to grow and develop properly. An enzyme called LPCAT3 is thought to incorporate arachidonic acid into membranes, but this has not yet been proven to occur in living animals. Here, Hashidate-Yoshida, Harayama et al. studied the role of LPCAT3 in newborn mice. The experiments show that this enzyme is found at high levels in the intestine and liver. Mice that lacked LPCAT3 had much lower levels of arachidonic acid compared with normal mice. These mice also showed signs of severe intestinal damage due to the build up of lipids from their mother's milk, and died within a few days of being born. The mice that lacked LPCAT3 had different amounts of another type of lipid—called triacylglycerols—in their intestine and liver. Normally, these lipids would be assembled into larger molecules called lipoproteins that are released into the blood stream and used in the muscles and other parts of the body. However, Hashidate-Yoshida, Harayama et al. found that in the mice missing LPCAT3, the triacylglycerols did not get assembled into lipoproteins and so they accumulated inside the intestine and liver cells. The experiments also show that high levels of arachidonic acid and other similar lipids in the membrane enable triacylglycerol molecules to cluster together, which increases the production of lipoproteins. Hashidate-Yoshida, Harayama et al.'s findings suggest that LPCAT3 incorporates arachidonic acid into the membrane of intestine and liver cells, which enables triacylglycerols to be assembled into lipoproteins. The next challenge will be to find out if LPCAT3 is also important for the production of lipoproteins in humans. If it is, then developing new therapies that alter the activity of this enzyme might be beneficial for patients with abnormal levels of lipids in the blood (known as dyslipidemia). DOI:http://dx.doi.org/10.7554/eLife.06328.002
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Affiliation(s)
| | - Takeshi Harayama
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Daisuke Hishikawa
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Ryo Morimoto
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Fumie Hamano
- Department of Lipidomics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Suzumi M Tokuoka
- Department of Lipidomics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Miki Eto
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Miwa Tamura-Nakano
- Communal Laboratory, National Center for Global Health and Medicine, Tokyo, Japan
| | - Rieko Yanobu-Takanashi
- Department of Laboratory Animal Medicine, National Center for Global Health and Medicine, Tokyo, Japan
| | - Yoshiko Mukumoto
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Developmental Biology, Kobe, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Developmental Biology, Kobe, Japan
| | - Tadashi Okamura
- Department of Laboratory Animal Medicine, National Center for Global Health and Medicine, Tokyo, Japan
| | - Yoshihiro Kita
- Department of Lipidomics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo, Japan
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95
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Alterations of protein expression in serum of infants with intrauterine growth restriction and different gestational ages. J Proteomics 2015; 119:169-82. [DOI: 10.1016/j.jprot.2015.02.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 02/16/2015] [Indexed: 01/19/2023]
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96
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Abstract
PURPOSE OF REVIEW To highlight some of the recent advances related to the control of polyunsaturated fatty acid (PUFA) incorporation and remodeling in membrane glycerophospholipids in inflammatory cells. RECENT FINDINGS Several enzymes have recently been identified that are associated with the control of PUFA incorporation and remodeling into membrane phospholipids and their release. The functional roles of the different enzyme isotypes in the control of PUFA availability for lipid mediator biosynthesis and cell signaling are only now being established. The expression of specific acyl-CoA synthetase, lysophospholipid acyltransferase and phospholipase A2 isotypes has recently been shown to have an impact on membrane PUFA content, on the production of lipid mediators and on inflammation. SUMMARY A better understanding of the complex processes associated with the control PUFA remodeling in membrane phospholipids may lead to the discovery of new therapeutic targets for the treatment of inflammatory diseases.
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Affiliation(s)
- Philippe Pierre Robichaud
- aDepartment of Chemistry and Biochemistry, Université de Moncton, Moncton, New Brunswick bDepartment of Microbiology, Infectious Diseases and Immunology, Université Laval, Québec, Quebec, Canada
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97
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98
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Josephson J, Turner JM, Field CJ, Wizzard PR, Nation PN, Sergi C, Ball RO, Pencharz PB, Wales PW. Parenteral Soy Oil and Fish Oil Emulsions. JPEN J Parenter Enteral Nutr 2014; 39:677-87. [DOI: 10.1177/0148607114556494] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 10/01/2014] [Indexed: 11/17/2022]
Affiliation(s)
| | - Justine M. Turner
- Department of Pediatrics, University of Alberta, Edmonton, Canada
- Department of Agricultural Food and Nutritional Science, University of Alberta, Edmonton, Canada
| | - Catherine J. Field
- Department of Agricultural Food and Nutritional Science, University of Alberta, Edmonton, Canada
| | | | - Patrick N. Nation
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Canada
| | - Consolato Sergi
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Canada
| | - Ronald O. Ball
- Department of Agricultural Food and Nutritional Science, University of Alberta, Edmonton, Canada
| | - Paul B. Pencharz
- Research Institute, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- Departments of Pediatrics and Nutritional Sciences, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Paul W. Wales
- Department of Pediatrics, University of Alberta, Edmonton, Canada
- Research Institute, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- Departments of Pediatrics and Nutritional Sciences, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- Division of General Surgery, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- Group for Improvement of Intestinal Function and Treatment, Hospital for Sick Children, Toronto, Ontario, Canada
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99
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Clark J, Kay RR, Kielkowska A, Niewczas I, Fets L, Oxley D, Stephens LR, Hawkins PT. Dictyostelium uses ether-linked inositol phospholipids for intracellular signalling. EMBO J 2014; 33:2188-200. [PMID: 25180230 DOI: 10.15252/embj.201488677] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Inositol phospholipids are critical regulators of membrane biology throughout eukaryotes. The general principle by which they perform these roles is conserved across species and involves binding of differentially phosphorylated inositol head groups to specific protein domains. This interaction serves to both recruit and regulate the activity of several different classes of protein which act on membrane surfaces. In mammalian cells, these phosphorylated inositol head groups are predominantly borne by a C38:4 diacylglycerol backbone. We show here that the inositol phospholipids of Dictyostelium are different, being highly enriched in an unusual C34:1e lipid backbone, 1-hexadecyl-2-(11Z-octadecenoyl)-sn-glycero-3-phospho-(1'-myo-inositol), in which the sn-1 position contains an ether-linked C16:0 chain; they are thus plasmanylinositols. These plasmanylinositols respond acutely to stimulation of cells with chemoattractants, and their levels are regulated by PIPKs, PI3Ks and PTEN. In mammals and now in Dictyostelium, the hydrocarbon chains of inositol phospholipids are a highly selected subset of those available to other phospholipids, suggesting that different molecular selectors are at play in these organisms but serve a common, evolutionarily conserved purpose.
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Affiliation(s)
- Jonathan Clark
- Babraham Biosciences Technology Babraham Research Campus, Cambridge, UK
| | - Robert R Kay
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Anna Kielkowska
- Babraham Biosciences Technology Babraham Research Campus, Cambridge, UK
| | - Izabella Niewczas
- Babraham Biosciences Technology Babraham Research Campus, Cambridge, UK
| | - Louise Fets
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - David Oxley
- Signalling Programme Babraham Research Campus, Cambridge, UK
| | - Len R Stephens
- Signalling Programme Babraham Research Campus, Cambridge, UK
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100
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Enrichment of phosphatidylinositols with specific acyl chains. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:1501-8. [DOI: 10.1016/j.bbamem.2013.10.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 09/25/2013] [Accepted: 10/03/2013] [Indexed: 12/21/2022]
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