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Abstract
Tafazzin is the mitochondrial enzyme that catalyzes transacylation between a phospholipid and a lysophospholipid in remodeling. Mutations in tafazzin cause Barth syndrome, a potentially life-threatening disease with the major symptom being cardiomyopathy. In the tafazzin-deficient heart, cardiolipin (CL) acyl chains become abnormally heterogeneous unlike those in the normal heart with a single dominant linoleoyl species, tetralinoleoyl CL. In addition, the amount of CL decreases and monolysocardiolipin (MLCL) accumulates. Here we determine using high-resolution 31P nuclear magnetic resonance with cryoprobe technology the fundamental phospholipid composition, including the major but oxidation-labile plasmalogens, in the tafazzin-knockdown (TAZ-KD) mouse heart as a model of Barth syndrome. In addition to confirming a lower level of CL (6.4 ± 0.1 → 2.0 ± 0.4 mol % of the total phospholipid) and accumulation of MLCL (not detected → 3.3 ± 0.5 mol %) in the TAZ-KD, we found a substantial reduction in the level of plasmenylcholine (30.8 ± 2.8 → 18.1 ± 3.1 mol %), the most abundant phospholipid in the control wild type. A quantitative Western blot revealed that while the level of peroxisomes, where early steps of plasmalogen synthesis take place, was normal in the TAZ-KD model, expression of Far1 as a rate-determining enzyme in plasmalogen synthesis was dramatically upregulated by 8.3 (±1.6)-fold to accelerate the synthesis in response to the reduced level of plasmalogen. We confirmed lyso-plasmenylcholine or plasmenylcholine is a substrate of purified tafazzin for transacylation with CL or MLCL, respectively. Our results suggest that plasmenylcholine, abundant in linoleoyl species, is important in remodeling CL in the heart. Tafazzin deficiency thus has a major impact on the cardiac plasmenylcholine level and thereby its functions.
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Affiliation(s)
- Tomohiro Kimura
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Atsuko K. Kimura
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Mindong Ren
- Department of Cell Biology, NYU Langone Medical Center, New York, NY 10016
| | - Bob Berno
- Department of Chemistry, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Yang Xu
- Department of Anesthesiology, NYU Langone Medical Center, New York, NY 10016
| | - Michael Schlame
- Department of Cell Biology, NYU Langone Medical Center, New York, NY 10016
- Department of Anesthesiology, NYU Langone Medical Center, New York, NY 10016
| | - Richard M. Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
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Gorgas K, Teigler A, Komljenovic D, Just WW. The ether lipid-deficient mouse: Tracking down plasmalogen functions. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 2006; 1763:1511-26. [PMID: 17027098 DOI: 10.1016/j.bbamcr.2006.08.038] [Citation(s) in RCA: 157] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 08/15/2006] [Accepted: 08/23/2006] [Indexed: 10/24/2022]
Abstract
Chemical and physico-chemical properties as well as physiological functions of major mammalian ether-linked glycerolipids, including plasmalogens were reviewed. Their chemical structures were described and their effect on membrane fluidity and membrane fusion discussed. The recent generation of mouse models with ether lipid deficiency offered the possibility to study ether lipid and particularly plasmalogen functions in vivo. Ether lipid-deficient mice revealed severe phenotypic alterations, including arrest of spermatogenesis, development of cataract and defects in central nervous system myelination. In several cell culture systems lack of plasmalogens impaired intracellular cholesterol distribution affecting plasma membrane functions and structural changes of ER and Golgi cisternae. Based on these phenotypic anomalies that were accurately described conclusions were drawn on putative functions of plasmalogens. These functions were related to cell-cell or cell-extracellular matrix interactions, formation of lipid raft microdomains and intracellular cholesterol homeostasis. There are several human disorders, such as Zellweger syndrome, rhizomelic chondrodysplasia punctata, Alzheimer's disease, Down syndrome, and Niemann-Pick type C disease that are distinguished by altered tissue plasmalogen concentrations. The role plasmalogens might play in the pathology of these disorders is discussed.
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Affiliation(s)
- Karin Gorgas
- Institut für Anatomie und Zellbiologie, Abteilung Medizinische Zellbiologie, Im Neuenheimer Feld 307, D-69120 Heidelberg, Germany
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van den Brink DM, Brites P, Haasjes J, Wierzbicki AS, Mitchell J, Lambert-Hamill M, de Belleroche J, Jansen GA, Waterham HR, Wanders RJA. Identification of PEX7 as the second gene involved in Refsum disease. Am J Hum Genet 2003; 72:471-7. [PMID: 12522768 PMCID: PMC379239 DOI: 10.1086/346093] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2002] [Accepted: 11/04/2002] [Indexed: 12/27/2022] Open
Abstract
Patients affected with Refsum disease (RD) have elevated levels of phytanic acid due to a deficiency of the peroxisomal enzyme phytanoyl-CoA hydroxylase (PhyH). In most patients with RD, disease-causing mutations in the PHYH gene have been identified, but, in a subset, no mutations could be found, indicating that the condition is genetically heterogeneous. Linkage analysis of a few patients diagnosed with RD, but without mutations in PHYH, suggested a second locus on chromosome 6q22-24. This region includes the PEX7 gene, which codes for the peroxin 7 receptor protein required for peroxisomal import of proteins containing a peroxisomal targeting signal type 2. Mutations in PEX7 normally cause rhizomelic chondrodysplasia punctata type 1, a severe peroxisomal disorder. Biochemical analyses of the patients with RD revealed defects not only in phytanic acid alpha-oxidation but also in plasmalogen synthesis and peroxisomal thiolase. Furthermore, we identified mutations in the PEX7 gene. Our data show that mutations in the PEX7 gene may result in a broad clinical spectrum ranging from severe rhizomelic chondrodysplasia punctata to relatively mild RD and that clinical diagnosis of conditions involving retinitis pigmentosa, ataxia, and polyneuropathy may require a full screen of peroxisomal functions.
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Affiliation(s)
- Daan M. van den Brink
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Pedro Brites
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Janet Haasjes
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Anthony S. Wierzbicki
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - John Mitchell
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Michelle Lambert-Hamill
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Jacqueline de Belleroche
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Gerbert A. Jansen
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Hans R. Waterham
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
| | - Ronald J. A. Wanders
- Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; Department of Chemical Pathology, King’s College London, St. Thomas' Hospital Campus, Refsum’s Disease Clinic, Chelsea & Westminster Hospital, and Department of Neuromuscular Disease, Faculty of Medicine, Imperial College Medical School, Charing Cross Hospital Campus, London
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Gaposchkin DP, Zoeller RA. Plasmalogen status influences docosahexaenoic acid levels in a macrophage cell line. Insights using ether lipid-deficient variants. J Lipid Res 1999; 40:495-503. [PMID: 10064738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Previously, this laboratory reported the isolation of variants, RAW. 12 and RAW.108, from the macrophage-like cell line RAW 264.7 that are defective in plasmalogen biosynthesis [Zoeller, R.A. et al. 1992. J. Biol. Chem. 267: 8299-8306]. Fatty acid analysis showed significant changes in the mutants in the ethanolamine phospholipids (PE), the only phospholipid class in which the plasmalogen species, plasmenylethanolamine, contributes significantly. Within the PE fraction, docosapentaenoic (DPA; 22:5n-3) and docosahexaenoic (DHA; 22:6n-3) acids were reduced by approximately 50% in the variants while the levels of arachidonic acid (AA; 20:4n-6) remained unaffected. The decrease in DHA was accompanied by a 50% decrease in labeling PE with [3H]DHA over a 90-min period. Restoration of plasmenylethanolamine by supplementing the growth medium with sn -1-hexadecylglycerol (HG) completely reversed these changes in RAW. 108. Pre-existing pools of plasmenylethanolamine were not required for restoration of normal [3H]DHA labeling; addition of HG only during the labeling period was sufficient. Due to the loss of Delta1'-desaturase in RAW.12, HG supplementation resulted in the accumulation of plasmenylethanolamine's immediate biosynthetic precursor, plasmanylethanolamine. Even though this latter phospholipid contained only the ether functionality (lacking the vinyl ether double bond) it was sufficient to restore wild type-like fatty acid composition and DHA labeling of the ethanolamine phospholipids, identifying the ether bond as a structural determinant for this specificity. In summary, we have used these mutants to establish that the plasmalogen status of a cell can influence the levels of certain polyunsaturated fatty acids. These results support the notion that certain polyunsaturated fatty acids, such as DHA, can be selectively targeted to plasmalogens and that this targeting occurs during de novo biosynthesis, or shortly thereafter, through modification of nascent plasmalogen pools.
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Affiliation(s)
- D P Gaposchkin
- Departments of Pathology and Laboratory Medicine, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA
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