101
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Abstract
Gangliosides are sialic acid containing glycosphingolipids, which are abundant in mammalian brain tissue. Several fatal human diseases are caused by defects in glycolipid metabolism. Defects in their degradation lead to an accumulation of metabolites upstream of the defective reactions, whereas defects in their biosynthesis lead to diverse problems in a large number of organs.Gangliosides are primarily positioned with their ceramide anchor in the neuronal plasma membrane and the glycan head group exposed on the cell surface. Their biosynthesis starts in the endoplasmic reticulum with the formation of the ceramide anchor, followed by sequential glycosylation reactions, mainly at the luminal surface of Golgi and TGN membranes, a combinatorial process, which is catalyzed by often promiscuous membrane-bound glycosyltransferases.Thereafter, the gangliosides are transported to the plasma membrane by exocytotic membrane flow. After endocytosis, they are degraded within the endolysosomal compartments by a complex machinery of degrading enzymes, lipid-binding activator proteins, and negatively charged lipids.
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Affiliation(s)
- Bernadette Breiden
- LIMES Institute, Membrane Biology & Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
| | - Konrad Sandhoff
- LIMES Institute, Membrane Biology & Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany.
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102
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Kirkegaard T, Gray J, Priestman DA, Wallom KL, Atkins J, Olsen OD, Klein A, Drndarski S, Petersen NHT, Ingemann L, Smith DA, Morris L, Bornæs C, Jørgensen SH, Williams I, Hinsby A, Arenz C, Begley D, Jäättelä M, Platt FM. Heat shock protein-based therapy as a potential candidate for treating the sphingolipidoses. Sci Transl Med 2017; 8:355ra118. [PMID: 27605553 DOI: 10.1126/scitranslmed.aad9823] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 08/18/2016] [Indexed: 12/17/2022]
Abstract
Lysosomal storage diseases (LSDs) often manifest with severe systemic and central nervous system (CNS) symptoms. The existing treatment options are limited and have no or only modest efficacy against neurological manifestations of disease. We demonstrate that recombinant human heat shock protein 70 (HSP70) improves the binding of several sphingolipid-degrading enzymes to their essential cofactor bis(monoacyl)glycerophosphate in vitro. HSP70 treatment reversed lysosomal pathology in primary fibroblasts from 14 patients with eight different LSDs. HSP70 penetrated effectively into murine tissues including the CNS and inhibited glycosphingolipid accumulation in murine models of Fabry disease (Gla(-/-)), Sandhoff disease (Hexb(-/-)), and Niemann-Pick disease type C (Npc1(-/-)) and attenuated a wide spectrum of disease-associated neurological symptoms in Hexb(-/-) and Npc1(-/-) mice. Oral administration of arimoclomol, a small-molecule coinducer of HSPs that is currently in clinical trials for Niemann-Pick disease type C (NPC), recapitulated the effects of recombinant human HSP70, suggesting that heat shock protein-based therapies merit clinical evaluation for treating LSDs.
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Affiliation(s)
| | - James Gray
- Department of Pharmacology, University of Oxford, Oxford, U.K
| | | | | | - Jennifer Atkins
- Department of Pharmacology, University of Oxford, Oxford, U.K
| | - Ole Dines Olsen
- Orphazyme ApS, Copenhagen, Denmark. Cell Death and Metabolism Unit, Center for Autophagy, Recycling, and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Alexander Klein
- Institut für Chemie der Humboldt-Universität zu Berlin, Berlin, Germany
| | | | | | | | - David A Smith
- Department of Pharmacology, University of Oxford, Oxford, U.K
| | - Lauren Morris
- Department of Pharmacology, University of Oxford, Oxford, U.K
| | | | | | - Ian Williams
- Department of Pharmacology, University of Oxford, Oxford, U.K
| | | | - Christoph Arenz
- Institut für Chemie der Humboldt-Universität zu Berlin, Berlin, Germany
| | - David Begley
- Institute of Pharmaceutical Science, King's College London, London, U.K
| | - Marja Jäättelä
- Cell Death and Metabolism Unit, Center for Autophagy, Recycling, and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Frances M Platt
- Department of Pharmacology, University of Oxford, Oxford, U.K
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103
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Davis W, Tew KD. ATP-binding cassette transporter-2 (ABCA2) as a therapeutic target. Biochem Pharmacol 2017; 151:188-200. [PMID: 29223352 DOI: 10.1016/j.bcp.2017.11.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 11/27/2017] [Indexed: 12/28/2022]
Abstract
The ATP binding cassette transporter ABCA2 is primarily an endolysosomal membrane protein that demonstrates pleiotropic functionalities, coalescing around the maintenance of homeostasis of sterols, sphingolipids and cholesterol. It is most highly expressed in brain tissue and ABCA2 knockout mice express neurological defects consistent with aberrant myelination. Increased expression of the transporter has been linked with resistance to cancer drugs, particularly those possessing a steroid backbone and gene expression (in concert with other genes involved in cholesterol metabolism) was found to be regulated by sterols. Moreover, in macrophages ABCA2 is influenced by sterols and has a role in regulating cholesterol sequestration, potentially important in cardiovascular disease. Accumulating data indicate the critical importance of ABCA2 in mediating movement of sphingolipids within cellular compartments and these have been implicated in various aspects of cholesterol trafficking. Perhaps because the functions of ABCA2 are linked with membrane building blocks, there are reports linking it with human pathologies, including, cholesterolemias and cardiovascular disease, Alzheimer's and cancer. The present review addresses whether there is now sufficient information to consider ABCA2 as a plausible therapeutic target.
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Affiliation(s)
- Warren Davis
- Dept. of Cell & Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, BSB, MSC 509, Charleston, SC 29425, United States
| | - Kenneth D Tew
- Dept. of Cell & Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, BSB, MSC 509, Charleston, SC 29425, United States.
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104
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Bryksa BC, Yada RY. Protein Structure Insights into the Bilayer Interactions of the Saposin-Like Domain of Solanum tuberosum Aspartic Protease. Sci Rep 2017; 7:16911. [PMID: 29208977 PMCID: PMC5717070 DOI: 10.1038/s41598-017-16734-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 11/16/2017] [Indexed: 12/26/2022] Open
Abstract
Many plant aspartic proteases contain a saposin-like domain whose principal functions are intracellular sorting and host defence. Its structure is characterised by helical segments cross-linked by three highly conserved cystines. The present study on the saposin-like domain of Solanum tuberosum aspartic protease revealed that acidification from inactive to active conditions causes dimerisation and a strand-to-helix secondary structure transition independent of bilayer interaction. Bilayer fusion was shown to occur under reducing conditions yielding a faster shift to larger vesicle sizes relative to native conditions, implying that a lower level structural motif might be bilayer-active. Characterisation of peptide sequences based on the domain’s secondary structural regions showed helix-3 to be active (~4% of the full domain’s activity), and mutation of its sole positively charged residue resulted in loss of activity and disordering of structure. Also, the peptides’ respective circular dichroism spectra suggested that native folding within the full domain is dependent on surrounding structure. Overall, the present study reveals that the aspartic protease saposin-like domain active structure is an open saposin fold dimer whose formation is pH-dependent, and that a bilayer-active motif shared among non-saposin membrane-active proteins including certain plant defence proteins is nested within an overall structure essential for native functionality.
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Affiliation(s)
- Brian C Bryksa
- Ontario Agricultural College, University of Guelph, N1G 2W1, Guelph, Ontario, Canada
| | - Rickey Y Yada
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, V6T 1Z4, British Columbia, Canada.
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105
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Saito T, Tanaka Y, Morishita Y, Ishibashi K. Proteomic analysis of AQP11-null kidney: Proximal tubular type polycystic kidney disease. Biochem Biophys Rep 2017; 13:17-21. [PMID: 29204517 PMCID: PMC5709289 DOI: 10.1016/j.bbrep.2017.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/10/2017] [Accepted: 11/13/2017] [Indexed: 12/28/2022] Open
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is caused by the mutation of polycystins (PC-1 or PC-2), in which cysts start from the collecting duct to extend to all nephron segments with eventual end stage renal failure. The cyst development is attenuated by a vasopressin V2 receptor antagonist tolvaptan which, however, will not affect proximal tubule cysts devoid of V2 receptor. Aquaporin-11 (AQP11) is expressed selectively in the proximal tubule of the kidney and AQP11-null kidneys have a disruptive PC-1 trafficking to the plasma membrane to develop polycystic kidneys. Here, we analyzed AQP11-null kidneys at the beginning of cyst formation by quantitative proteomic analysis using Tandem Mass Tag (TMT). Among ~ 1200 identified proteins, 124 proteins were differently expressed by > 1.5 or < 0.8 fold change. A pancreatic stone inhibitor or a growth factor, lithostathine-1 (Reg1) was most enhanced by 5 folds which was confirmed by western blot, while mitochondria-related proteins were downregulated. The identified proteins will be new target molecules for the treatment of proximal tubular cysts and helpful to explore the functional roles of AQP11 in the kidney. Proteomic analysis of the kidney from AQP11-null mice of proximal tubular specific ADPKD. Among ~ 1200 identified proteins, 124 proteins were differently expressed by > 1.5 or < 0.8 fold change. Mitochondrial proteins were downregulated reflecting a functional mitochondrial damage in cystic epithelia. Reg1 protein was most enhanced by 5 folds which was confirmed by western blot.
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Affiliation(s)
- Tatsuya Saito
- Department of Pathophysiology, Faculty of Clinical Pharmacy, Meiji Pharmaceutical University, Tokyo 204-8588, Japan
- Corresponding author.
| | - Yasuko Tanaka
- Department of Pathophysiology, Faculty of Clinical Pharmacy, Meiji Pharmaceutical University, Tokyo 204-8588, Japan
| | - Yoshiyuki Morishita
- Department of Nephrology, Saitama Medical Center, Jichi Medical University, Saitama 330-8503, Japan
| | - Kenichi Ishibashi
- Department of Pathophysiology, Faculty of Clinical Pharmacy, Meiji Pharmaceutical University, Tokyo 204-8588, Japan
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106
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den Hoedt S, Janssen CI, Astarita G, Piomelli D, Leijten FP, Crivelli SM, Verhoeven AJ, de Vries HE, Walter J, Martinez-Martinez P, Sijbrands EJ, Kiliaan AJ, Mulder MT. Pleiotropic Effect of Human ApoE4 on Cerebral Ceramide and Saturated Fatty Acid Levels. J Alzheimers Dis 2017; 60:769-781. [DOI: 10.3233/jad-160739] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Sandra den Hoedt
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Carola I.F. Janssen
- Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Giuseppe Astarita
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington DC, USA
| | - Daniele Piomelli
- Department of Pharmacology, University of California Irvine, CA, USA
| | - Frank P.J. Leijten
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Simone M. Crivelli
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Adrie J.M. Verhoeven
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Helga E. de Vries
- Department of Molecular Cell Biology and Immunology, Neuroscience Campus Amsterdam, VU Medical Center, Amsterdam, The Netherlands
| | - Jochen Walter
- Department of Neurology, University of Bonn, Bonn, Germany
| | - Pilar Martinez-Martinez
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Eric J.G. Sijbrands
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Amanda J. Kiliaan
- Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Monique T. Mulder
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
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107
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Abstract
Sphingolipidoses are genetically inherited diseases in which genetic mutations lead to functional deficiencies in the enzymes needed for lysosomal degradation of sphingolipid substrates. As a consequence, nondegradable lipids enrich in the lysosomes and lead to fatal pathological phenotypes in affected individuals. In this review, different drug-based treatment strategies including enzyme replacement therapy and substrate reduction therapy are discussed. A special focus is on the concept of pharmacological chaperones, one of which recently acquired clinical approval within the EU. On the basis of the different limitations for each approach, possible future directions of research are discussed.
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108
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Wang M, Palavicini JP, Cseresznye A, Han X. Strategy for Quantitative Analysis of Isomeric Bis(monoacylglycero)phosphate and Phosphatidylglycerol Species by Shotgun Lipidomics after One-Step Methylation. Anal Chem 2017; 89:8490-8495. [PMID: 28708380 DOI: 10.1021/acs.analchem.7b02058] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Understanding the cellular function and metabolism of bis(monoacylglycero)phosphate (BMP), an important but low-abundance class of phospholipids, has been hindered due to its difficulties to be resolved from its structural isomer (i.e., phosphatidylglycerol, PG, another low-abundance class of phospholipids). A novel strategy for quantitative analysis of BMP and PG species was developed after one-step methylation of lipid extracts in combination with high mass accuracy/resolution mass spectrometry after direct infusion (i.e., shotgun lipidomics). The novel strategy was applied for quantitative analysis of mouse hepatic BMP and PG species and their changes induced by long-term high-fat diet (HFD) feeding. Interestingly, we revealed that HFD-fed mice display a dramatic accumulation of hepatic BMP compared to chow-fed littermates. We believe the development of this novel strategy could greatly facilitate our understanding of the role of BMP in biological systems.
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Affiliation(s)
- Miao Wang
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute , Orlando, Florida 32827, United States
| | - Juan Pablo Palavicini
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute , Orlando, Florida 32827, United States
| | - Adam Cseresznye
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute , Orlando, Florida 32827, United States
| | - Xianlin Han
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute , Orlando, Florida 32827, United States
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109
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Lee C, Guo J, Zeng W, Kim S, She J, Cang C, Ren D, Jiang Y. The lysosomal potassium channel TMEM175 adopts a novel tetrameric architecture. Nature 2017; 547:472-475. [PMID: 28723891 PMCID: PMC5901963 DOI: 10.1038/nature23269] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/06/2017] [Indexed: 11/09/2022]
Abstract
TMEM175 is a lysosomal K+ channel that is important for maintaining the membrane potential and pH stability in lysosomes. It contains two homologous copies of a six-transmembrane-helix (6-TM) domain, which has no sequence homology to the canonical tetrameric K+ channels and lacks the TVGYG selectivity filter motif found in these channels. The prokaryotic TMEM175 channel, which is present in a subset of bacteria and archaea, contains only a single 6-TM domain and functions as a tetramer. Here, we present the crystal structure of a prokaryotic TMEM175 channel from Chamaesiphon minutus, CmTMEM175, the architecture of which represents a completely different fold from that of canonical K+ channels. All six transmembrane helices of CmTMEM175 are tightly packed within each subunit without undergoing domain swapping. The highly conserved TM1 helix acts as the pore-lining inner helix, creating an hourglass-shaped ion permeation pathway in the channel tetramer. Three layers of hydrophobic residues on the carboxy-terminal half of the TM1 helices form a bottleneck along the ion conduction pathway and serve as the selectivity filter of the channel. Mutagenesis analysis suggests that the first layer of the highly conserved isoleucine residues in the filter is primarily responsible for channel selectivity. Thus, the structure of CmTMEM175 represents a novel architecture of a tetrameric cation channel whose ion selectivity mechanism appears to be distinct from that of the classical K+ channel family.
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Affiliation(s)
- Changkeun Lee
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815-6789, USA
| | - Jiangtao Guo
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
| | - Weizhong Zeng
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815-6789, USA
| | - Sunghoon Kim
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815-6789, USA
| | - Ji She
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
| | - Chunlei Cang
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Dejian Ren
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Youxing Jiang
- Department of Physiology and Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815-6789, USA
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110
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Vartabedian VF, Savage PB, Teyton L. The processing and presentation of lipids and glycolipids to the immune system. Immunol Rev 2017; 272:109-19. [PMID: 27319346 DOI: 10.1111/imr.12431] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The recognition of CD1-lipid complexes by T cells was discovered 20 years ago and has since been an emerging and expanding field of investigation. Unlike protein antigens, which are presented on MHC class I and II molecules, lipids can only be presented by CD1 molecules, a unique family of MHC-like proteins whose singularity is a hydrophobic antigen-binding groove. The processing and loading of lipid antigens inside this groove of CD1 molecules require localization to endosomal and lysosomal subcellular compartments and their acidic pHs. This particular environment provides the necessary glycolytic enzymes and lipases that process lipid and glycolipid antigens, as well as a set of lipid transfer proteins that load the final version of the antigen inside the groove of CD1. The overall sequence of events needed for efficient presentation of lipid antigens is now understood and presented in this review. However, a large number of important details have been elusive. This elusiveness is linked to the inherent technical difficulties of studying lipids and the lipid-protein interface in vitro and in vivo. Here, we will expose some of those limitations and describe new approaches to address them during the characterization of lipids and glycolipids antigen presentation.
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Affiliation(s)
- Vincent F Vartabedian
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA
| | - Paul B Savage
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - Luc Teyton
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA
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111
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Tsuji T, Fujimoto M, Tatematsu T, Cheng J, Orii M, Takatori S, Fujimoto T. Niemann-Pick type C proteins promote microautophagy by expanding raft-like membrane domains in the yeast vacuole. eLife 2017; 6:e25960. [PMID: 28590904 PMCID: PMC5462540 DOI: 10.7554/elife.25960] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 05/16/2017] [Indexed: 11/13/2022] Open
Abstract
Niemann-Pick type C is a storage disease caused by dysfunction of NPC proteins, which transport cholesterol from the lumen of lysosomes to the limiting membrane of that compartment. Using freeze fracture electron microscopy, we show here that the yeast NPC orthologs, Ncr1p and Npc2p, are essential for formation and expansion of raft-like domains in the vacuolar (lysosome) membrane, both in stationary phase and in acute nitrogen starvation. Moreover, the expanded raft-like domains engulf lipid droplets by a microautophagic mechanism. We also found that the multivesicular body pathway plays a crucial role in microautophagy in acute nitrogen starvation by delivering sterol to the vacuole. These data show that NPC proteins promote microautophagy in stationary phase and under nitrogen starvation conditions, likely by increasing sterol in the limiting membrane of the vacuole.
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Affiliation(s)
- Takuma Tsuji
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Megumi Fujimoto
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tsuyako Tatematsu
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Jinglei Cheng
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Minami Orii
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Sho Takatori
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toyoshi Fujimoto
- Department of Molecular Cell Biology and Anatomy, Nagoya University Graduate School of Medicine, Nagoya, Japan
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112
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Abstract
Lysosomes are cytoplasmic organelles that contain a variety of different hydrolases. A genetic deficiency in the enzymatic activity of one of these hydrolases will lead to the accumulation of the material meant for lysosomal degradation. Examples include glycogen in the case of Pompe disease, glycosaminoglycans in the case of the mucopolysaccharidoses, glycoproteins in the cases of the oligosaccharidoses, and sphingolipids in the cases of Niemann-Pick disease types A and B, Gaucher disease, Tay-Sachs disease, Krabbe disease, and metachromatic leukodystrophy. Sometimes, the lysosomal storage can be caused not by the enzymatic deficiency of one of the hydrolases, but by the deficiency of an activator protein, as occurs in the AB variant of GM2 gangliosidosis. Still other times, the accumulated lysosomal material results from failed egress of a small molecule as a consequence of a deficient transporter, as in cystinosis or Salla disease. In the last couple of decades, enzyme replacement therapy has become available for a number of lysosomal storage diseases. Examples include imiglucerase, taliglucerase and velaglucerase for Gaucher disease, laronidase for Hurler disease, idursulfase for Hunter disease, elosulfase for Morquio disease, galsulfase for Maroteaux-Lamy disease, alglucosidase alfa for Pompe disease, and agalsidase alfa and beta for Fabry disease. In addition, substrate reduction therapy has been approved for certain disorders, such as eliglustat for Gaucher disease. The advent of treatment options for some of these disorders has led to newborn screening pilot studies, and ultimately to the addition of Pompe disease and Hurler disease to the Recommended Uniform Screening Panel (RUSP) in 2015 and 2016, respectively.
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Affiliation(s)
- Carlos R. Ferreira
- Division of Genetics and Metabolism, Children’s National Health System, Washington, DC, USA
- George Washington University School of Medicine & Health Sciences, Washington, DC, USA
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - William A. Gahl
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
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113
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Ries M. Enzyme replacement therapy and beyond-in memoriam Roscoe O. Brady, M.D. (1923-2016). J Inherit Metab Dis 2017; 40:343-356. [PMID: 28314976 DOI: 10.1007/s10545-017-0032-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 02/17/2017] [Accepted: 02/21/2017] [Indexed: 11/28/2022]
Abstract
Lysosomal storage disorders are strong candidates for the development of specific innovative therapies. The discovery of enzyme deficiencies is an important milestone in understanding the underlying cause of disease. Being able to replace the first missing enzyme in a lysosomal storage required three decades of dedicated research. Successful drug development for lysosomal storage disorders was fostered by the U.S. Orphan Drug Act. Various optimization strategies have the potential to overcome the current limitations of enzyme replacement therapies. In addition, substrate reduction therapies are an alternative approach to treat lysosomal storage disorders, chemical chaperones enhance residual enzyme activity, and small molecules can facilitate substrate transport through subcellular compartments. Bone-marrow derived multipotent stem cells and gene therapies have received FDA orphan drug designation status. The science of small clinical trials played an essential role: non-neurological endpoints, biomarker, and regulatory alignment are key factors in successful drug development for lysosomal storage disorders. Being able to treat brain disease is the next frontier. This review is dedicated to the memory of Roscoe O. Brady, an early pioneer in the research of lysosomal storage diseases.
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Affiliation(s)
- Markus Ries
- Pediatric Neurology and Metabolic Medicine, Center for Pediatric and Adolescent Medicine, Heidelberg University Hospital, Heidelberg, Germany.
- Center for Rare Disorders, Heidelberg University Hospital, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany.
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114
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Lecommandeur E, Baker D, Cox TM, Nicholls AW, Griffin JL. Alterations in endo-lysosomal function induce similar hepatic lipid profiles in rodent models of drug-induced phospholipidosis and Sandhoff disease. J Lipid Res 2017; 58:1306-1314. [PMID: 28377426 DOI: 10.1194/jlr.m073395] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/28/2017] [Indexed: 12/21/2022] Open
Abstract
Drug-induced phospholipidosis (DIPL) is characterized by an increase in the phospholipid content of the cell and the accumulation of drugs and lipids inside the lysosomes of affected tissues, including in the liver. Although of uncertain pathological significance for patients, the condition remains a major impediment for the clinical development of new drugs. Human Sandhoff disease (SD) is caused by inherited defects of the β subunit of lysosomal β-hexosaminidases (Hex) A and B, leading to a large array of symptoms, including neurodegeneration and ultimately death by the age of 4 in its most common form. The substrates of Hex A and B, gangliosides GM2 and GA2, accumulate inside the lysosomes of the CNS and in peripheral organs. Given that both DIPL and SD are associated with lysosomes and lipid metabolism in general, we measured the hepatic lipid profiles in rodent models of these two conditions using untargeted LC/MS to examine potential commonalities. Both model systems shared a number of perturbed lipid pathways, notably those involving metabolism of cholesteryl esters, lysophosphatidylcholines, bis(monoacylglycero)phosphates, and ceramides. We report here profound alterations in lipid metabolism in the SD liver. In addition, DIPL induced a wide range of lipid changes not previously observed in the liver, highlighting similarities with those detected in the model of SD and raising concerns that these lipid changes may be associated with underlying pathology associated with lysosomal storage disorders.
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Affiliation(s)
- Emmanuelle Lecommandeur
- Department of Biochemistry, Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
| | | | - Timothy M Cox
- Department of Medicine, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | | | - Julian L Griffin
- Department of Biochemistry, Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom.
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115
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Abdul-Hammed M, Breiden B, Schwarzmann G, Sandhoff K. Lipids regulate the hydrolysis of membrane bound glucosylceramide by lysosomal β-glucocerebrosidase. J Lipid Res 2017; 58:563-577. [PMID: 28126847 DOI: 10.1194/jlr.m073510] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/24/2017] [Indexed: 01/24/2023] Open
Abstract
Glucosylceramide (GlcCer) is the primary storage lipid in the lysosomes of Gaucher patients and a secondary one in Niemann-Pick disease types A, B, and C. The regulatory roles of lipids on the hydrolysis of membrane bound GlcCer by lysosomal β-glucocerebrosidase (GBA1) was probed using a detergent-free liposomal assay. The degradation rarely occurs at uncharged liposomal surfaces in the absence of saposin (Sap) C. However, anionic lipids stimulate GlcCer hydrolysis at low pH by up to 1,000-fold depending on the nature and position of the negative charges in their head groups while cationic lipids inhibit the degradation, thus showing the importance of electrostatic interactions between the polycationic GBA1 and the negatively charged vesicle surfaces at low pH. Ceramide, fatty acids, monoacylglycerol, and diacylglycerol also stimulate GlcCer hydrolysis while SM, sphingosine, and sphinganine play strong inhibitory roles, thereby explaining the secondary storage of GlcCer in Niemann-Pick diseases. Surprisingly, cholesterol stimulates GlcCer degradation in the presence of bis(monoacylglycero)phosphate (BMP). Sap C strongly stimulates GlcCer hydrolysis even in the absence of BMP and the regulatory roles of the intraendolysosomal lipids on its activity is discussed. Our data suggest that these strong modifiers of GlcCer hydrolysis affect the genotype-phenotype correlation in several cases of Gaucher patients independent of the types.
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Affiliation(s)
- Misbaudeen Abdul-Hammed
- Life and Medical Sciences (LIMES) Institut, Membrane Biology and Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany.,Biophysical Chemistry Group, Department of Pure and Applied Chemistry, Ladoke Akintola University of Technology, Ogbomoso, Nigeria
| | - Bernadette Breiden
- Life and Medical Sciences (LIMES) Institut, Membrane Biology and Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
| | - Günter Schwarzmann
- Life and Medical Sciences (LIMES) Institut, Membrane Biology and Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
| | - Konrad Sandhoff
- Life and Medical Sciences (LIMES) Institut, Membrane Biology and Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
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116
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Selective Lysosomal Transporter Degradation by Organelle Membrane Fusion. Dev Cell 2016; 40:151-167. [PMID: 28017618 DOI: 10.1016/j.devcel.2016.11.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 10/19/2016] [Accepted: 11/28/2016] [Indexed: 12/20/2022]
Abstract
Lysosomes rely on their resident transporter proteins to return products of catabolism to the cell for reuse and for cellular signaling, metal storage, and maintaining the lumenal environment. Despite their importance, little is known about the lifetime of these transporters or how they are regulated. Using Saccharomyces cerevisiae as a model, we discovered a new pathway intrinsic to homotypic lysosome membrane fusion that is responsible for their degradation. Transporter proteins are selectively sorted by the docking machinery into an area between apposing lysosome membranes, which is internalized and degraded by lumenal hydrolases upon organelle fusion. These proteins have diverse lifetimes that are regulated in response to protein misfolding, changing substrate levels, or TOR activation. Analogous to endocytosis for controlling surface protein levels, the "intralumenal fragment pathway" is critical for lysosome membrane remodeling required for organelle function in the context of cellular protein quality control, ion homeostasis, and metabolism.
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117
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Ciesielska A, Sas-Nowosielska H, Kwiatkowska K. Bis(monoacylglycero)phosphate inhibits TLR4-dependent RANTES production in macrophages. Int J Biochem Cell Biol 2016; 83:15-26. [PMID: 27939812 DOI: 10.1016/j.biocel.2016.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/14/2016] [Accepted: 12/06/2016] [Indexed: 01/10/2023]
Abstract
Toll-like receptor 4 (TLR4) is the receptor for bacterial lipopolysaccharide (LPS) triggering production of pro-inflammatory cytokines which help eradicate the bacteria but could also be harmful when overproduced. The signaling activity of TLR4 is modulated by cholesterol level in cellular membranes, which in turn is affected by bis(monoacylglycero)phosphate (BMP), a phospholipid enriched in late endosomes. We found that exogenously added BMP isomers become incorporated into the plasma membrane and intracellular vesicles of macrophages and strongly reduced LPS-stimulated production of a chemokine RANTES, which was correlated with inhibition of interferon regulatory factor 3 (IRF3) controlling Rantes expression. To investigate the mechanism underlying the influence of BMP on TLR4 signaling we applied Laurdan and studied the impact of BMP incorporation on lipid packing, a measure for membrane order. Enrichment of model and cellular membranes with BMP significantly reduced their order and the reduction was maintained during stimulation of cells with LPS. This effect of BMP was abolished by enrichment of macrophages with cholesterol. In parallel, the inhibitory effect of BMP exerted on the TLR4-dependent phosphorylation of IRF3 was also reversed. Taken together our results indicate that BMP reduces the order of macrophage membranes which contributes to the inhibition of TLR4-dependent RANTES production.
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Affiliation(s)
- Anna Ciesielska
- Laboratory of Molecular Membrane Biology, Department of Cell Biology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Hanna Sas-Nowosielska
- Laboratory for Imaging Tissue Structure and Function, Neurobiology Center, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Katarzyna Kwiatkowska
- Laboratory of Molecular Membrane Biology, Department of Cell Biology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, 3 Pasteur St., 02-093 Warsaw, Poland.
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118
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Can 'calpain-cathepsin hypothesis' explain Alzheimer neuronal death? Ageing Res Rev 2016; 32:169-179. [PMID: 27306474 DOI: 10.1016/j.arr.2016.05.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 05/10/2016] [Accepted: 05/19/2016] [Indexed: 01/08/2023]
Abstract
Neurons are highly specialized post-mitotic cells, so their homeostasis and survival depend on the tightly-regulated, continuous protein degradation, synthesis, and turnover. In neurons, autophagy is indispensable to facilitate recycling of long-lived, damaged proteins and organelles in a lysosome-dependent manner. Since lysosomal proteolysis under basal conditions performs an essential housekeeping function, inhibition of the proteolysis exacerbates level of neurodegeneration. The latter is characterized by an accumulation of abnormal proteins or organelles within autophagic vacuoles which reveal as 'granulo-vacuolar degenerations' on microscopy. Heat-shock protein70.1 (Hsp70.1), as a means of molecular chaperone and lysosomal stabilizer, is a potent survival protein that confers neuroprotection against diverse stimuli, but its depletion induces neurodegeneration via autophagy failure. In response to hydroxynonenal generated from linoleic or arachidonic acids by the reactive oxygen species, a specific oxidative injury 'carbonylation' occurs at the key site Arg469 of Hsp70.1. Oxidative stress-induced carbonylation of Hsp70.1, in coordination with the calpain-mediated cleavage, leads to lysosomal destabilization/rupture and release of cathepsins with the resultant neuronal death. Hsp70.1 carbonylation which occurs anywhere in the brain is indispensable for neuronal death, but extent of calpain activation should be more crucial for determining the cell death fate. Importantly, not only acute ischemia during stroke but also chronic ischemia due to ageing may cause calpain activation. Here, role of Hsp70.1-mediated lysosomal rupture is discussed by comparing ischemic and Alzheimer neuronal death. A common neuronal death cascade may exist between cerebral ischemia and Alzheimer's disease.
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119
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Human acid sphingomyelinase structures provide insight to molecular basis of Niemann-Pick disease. Nat Commun 2016; 7:13082. [PMID: 27725636 PMCID: PMC5062611 DOI: 10.1038/ncomms13082] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 09/01/2016] [Indexed: 12/18/2022] Open
Abstract
Acid sphingomyelinase (ASM) hydrolyzes sphingomyelin to ceramide and phosphocholine, essential components of myelin in neurons. Genetic alterations in ASM lead to ASM deficiency (ASMD) and have been linked to Niemann–Pick disease types A and B. Olipudase alfa, a recombinant form of human ASM, is being developed as enzyme replacement therapy to treat the non-neurological manifestations of ASMD. Here we present the human ASM holoenzyme and product bound structures encompassing all of the functional domains. The catalytic domain has a metallophosphatase fold, and two zinc ions and one reaction product phosphocholine are identified in a histidine-rich active site. The structures reveal the underlying catalytic mechanism, in which two zinc ions activate a water molecule for nucleophilic attack of the phosphodiester bond. Docking of sphingomyelin provides a model that allows insight into the selectivity of the enzyme and how the ASM domains collaborate to complete hydrolysis. Mapping of known mutations provides a basic understanding on correlations between enzyme dysfunction and phenotypes observed in ASMD patients. Genetic alterations in the protein acid sphingomyelinase (ASM) lead to ASM deficiency and have been associated with Niemann–Pick disease. Here, the authors report the crystal structures of ASM alone and bound to its product, and discuss the catalytic mechanism and its possible significance for patients with ASM deficiency.
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120
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Kuchař L, Asfaw B, Rybová J, Ledvinová J. Tandem Mass Spectrometry of Sphingolipids: Applications for Diagnosis of Sphingolipidoses. Adv Clin Chem 2016; 77:177-219. [PMID: 27717417 DOI: 10.1016/bs.acc.2016.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In recent years, mass spectrometry (MS) has become the dominant technology in lipidomic analysis. It is widely used in diagnosis and research of lipid metabolism disorders including those characterized by impairment of lysosomal functions and storage of nondegraded-degraded substrates. These rare diseases, which include sphingolipidoses, have severe and often fatal clinical consequences. Modern MS methods have contributed significantly to achieve a definitive diagnosis, which is essential in clinical practice to begin properly targeted patient care. Here we summarize MS and tandem MS methods used for qualitative and quantitative analysis of sphingolipids (SL) relative to the diagnostic process for sphingolipidoses and studies focusing on alterations in cell functions due to these disorders. This review covers the following topics: Tandem MS is sensitive and robust in determining the composition of sphingolipid classes in various biological materials. Its ability to establish SL metabolomic profiles using MS bench-top analyzers, significantly benefits the first stages of a diagnosis as well as metabolic studies of these disorders. It can thus contribute to a better understanding of the biological significance of SL.
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Affiliation(s)
- L Kuchař
- Charles University in Prague and General University Hospital, Prague, Czech Republic.
| | - B Asfaw
- Charles University in Prague and General University Hospital, Prague, Czech Republic
| | - J Rybová
- Charles University in Prague and General University Hospital, Prague, Czech Republic
| | - J Ledvinová
- Charles University in Prague and General University Hospital, Prague, Czech Republic.
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121
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Nakamura T, Sato K, Naruse N, Kitakaze K, Inokuma T, Hirokawa T, Shigenaga A, Itoh K, Otaka A. Tailored Synthesis of 162-Residue S-Monoglycosylated GM2-Activator Protein (GM2AP) Analogues that Allows Facile Access to a Protein Library. Chembiochem 2016; 17:1986-1992. [PMID: 27428709 DOI: 10.1002/cbic.201600400] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Indexed: 11/08/2022]
Abstract
A synthetic protocol for the preparation of 162-residue S-monoglycosylated GM2-activator protein (GM2AP) analogues bearing various amino acid substitutions for Thr69 has been developed. The facile incorporation of the replacements into the protein was achieved by means of a one-pot/N-to-C-directed sequential ligation strategy using readily accessible middle N-sulfanylethylanilide (SEAlide) peptides each consisting of seven amino acid residues. A kinetically controlled ligation protocol was successfully applied to the assembly of three peptide segments covering the GM2AP. The native chemical ligation (NCL) reactivities of the SEAlide peptides can be tuned by the presence or absence of phosphate salts. Furthermore, NCL of the alkyl thioester fragment [GM2AP (1-31)] with the N-terminal cysteinyl prolyl thioester [GM2AP (32-67)] proceeded smoothly to yield the 67-residue prolyl thioester, with the prolyl thioester moiety remaining intact. This newly developed strategy enabled the facile synthesis of GM2AP analogues. Thus, we refer to this synthetic protocol as "tailored synthesis" for the construction of a GM2AP library.
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Affiliation(s)
- Takahiro Nakamura
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Kohei Sato
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Naoto Naruse
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Keisuke Kitakaze
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Tsubasa Inokuma
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Takatsugu Hirokawa
- Molecular Profiling Research Center for Drug Discovery, AIST, 2-4-7 Aomi, Koto-ku, Tokyo, 135-0064, Japan
| | - Akira Shigenaga
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Kohji Itoh
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan
| | - Akira Otaka
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima, 770-8505, Japan.
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122
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Gray C, Thomas B, Upton R, Migas L, Eyers C, Barran P, Flitsch S. Applications of ion mobility mass spectrometry for high throughput, high resolution glycan analysis. Biochim Biophys Acta Gen Subj 2016; 1860:1688-709. [DOI: 10.1016/j.bbagen.2016.02.003] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/01/2016] [Accepted: 02/02/2016] [Indexed: 12/21/2022]
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123
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Xiong ZJ, Huang J, Poda G, Pomès R, Privé GG. Structure of Human Acid Sphingomyelinase Reveals the Role of the Saposin Domain in Activating Substrate Hydrolysis. J Mol Biol 2016; 428:3026-42. [PMID: 27349982 DOI: 10.1016/j.jmb.2016.06.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 06/14/2016] [Accepted: 06/16/2016] [Indexed: 11/29/2022]
Abstract
Acid sphingomyelinase (ASM) is a lysosomal phosphodiesterase that catalyzes the hydrolysis of sphingomyelin to produce ceramide and phosphocholine. While other lysosomal sphingolipid hydrolases require a saposin activator protein for full activity, the ASM polypeptide incorporates a built-in N-terminal saposin domain and does not require an external activator protein. Here, we report the crystal structure of human ASM and describe the organization of the three main regions of the enzyme: the N-terminal saposin domain, the proline-rich connector, and the catalytic domain. The saposin domain is tightly associated along an edge of the large, bowl-shaped catalytic domain and adopts an open form that exposes a hydrophobic concave surface approximately 30Å from the catalytic center. The calculated electrostatic potential of the enzyme is electropositive at the acidic pH of the lysosome, consistent with the strict requirement for the presence of acidic lipids in target membranes. Docking studies indicate that sphingomyelin binds with the ceramide-phosphate group positioned at the binuclear zinc center and molecular dynamic simulations indicate that the intrinsic flexibility of the saposin domain is important for monomer-dimer exchange and for membrane interactions. Overall, ASM uses a combination of electrostatic and hydrophobic interactions to cause local disruptions of target bilayers in order to bring the lipid headgroup to the catalytic center in a membrane-bound reaction.
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Affiliation(s)
- Zi-Jian Xiong
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Jingjing Huang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Gennady Poda
- Drug Discovery, Ontario Institute for Cancer Research, Toronto, Ontario, Canada; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Régis Pomès
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Gilbert G Privé
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; Princess Margaret Cancer Centre, Toronto, Ontario, Canada.
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Abstract
Lipids are essential components of a cell providing energy substrates for cellular processes, signaling intermediates, and building blocks for biological membranes. Lipids are constantly recycled and redistributed within a cell. Lysosomes play an important role in this recycling process that involves the recruitment of lipids to lysosomes via autophagy or endocytosis for their degradation by lysosomal hydrolases. The catabolites produced are redistributed to various cellular compartments to support basic cellular function. Several studies demonstrated a bidirectional relationship between lipids and lysosomes that regulate autophagy. While lysosomal degradation pathways regulate cellular lipid metabolism, lipids also regulate lysosome function and autophagy. In this review, we focus on this bidirectional relationship in the context of dietary lipids and provide an overview of recent evidence of how lipid-overload lipotoxicity, as observed in obesity and metabolic syndrome, impairs lysosomal function and autophagy that may eventually lead to cellular dysfunction or cell death.
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Affiliation(s)
- Bharat Jaishy
- Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| | - E Dale Abel
- Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242
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125
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Feng X, Yang J. Lysosomal Calcium in Neurodegeneration. MESSENGER (LOS ANGELES, CALIF. : PRINT) 2016; 5:56-66. [PMID: 29082116 PMCID: PMC5659362 DOI: 10.1166/msr.2016.1055] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lysosomes are the central organelles responsible for macromolecule recycling in the cell. Lysosomal dysfunction is the primary cause of lysosomal storage diseases (LSDs), and contributes significantly to the pathogenesis of common neurodegenerative diseases. The lysosomes are also intracellular stores for calcium ions, one of the most common second messenger in the cell. Lysosomal Ca2+ is required for diverse cellular processes including signal transduction, vesicular trafficking, autophagy, nutrient sensing, exocytosis, and membrane repair. In this review, we first summarize some recent progresses in the studies of lysosome Ca2+ regulation, with a focus on the newly discovered lysosomal Ca2+ channels and the mechanisms of lysosomal Ca2+ store refilling. We then discuss how defects in lysosomal Ca2+ release and store maintenance cause lysosomal dysfunction and neurodegeneration.
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Affiliation(s)
- Xinghua Feng
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, China
| | - Junsheng Yang
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, China
- The Department of Molecular, Cellular, and Developmental Biology, University of Michigan, 3089 Natural Science Building (Kraus), 830 North University, Ann Arbor, MI 48109, USA
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126
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Davidson CD, Fishman YI, Puskás I, Szemán J, Sohajda T, McCauliff LA, Sikora J, Storch J, Vanier MT, Szente L, Walkley SU, Dobrenis K. Efficacy and ototoxicity of different cyclodextrins in Niemann-Pick C disease. Ann Clin Transl Neurol 2016; 3:366-80. [PMID: 27231706 PMCID: PMC4863749 DOI: 10.1002/acn3.306] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 03/14/2016] [Accepted: 03/16/2016] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVE Niemann-Pick type C (NPC) disease is a fatal, neurodegenerative, lysosomal storage disorder characterized by intracellular accumulation of unesterified cholesterol (UC) and other lipids. While its mechanism of action remains unresolved, administration of 2-hydroxypropyl-β-cyclodextrin (HPβCD) has provided the greatest disease amelioration in animal models but is ototoxic. We evaluated other cyclodextrins (CDs) for treatment outcome and chemical interaction with disease-relevant substrates that could pertain to mechanism. METHODS NPC disease mice treated for 2 weeks with nine different CDs were evaluated for UC, and GM2 and GM3 ganglioside accumulation using immunohisto/cytochemical and biochemical assays. Auditory brainstem responses were determined in wild-type mice administered CDs. CD complexation with UC, gangliosides, and other lipids was quantified. RESULTS Four HPβCDs varying in degrees of substitution, including one currently in clinical trial, showed equivalent storage reduction, while other CDs showed significant differences in relative ototoxicity and efficacy, with reductions similar for the brain and liver. Importantly, HPγCD and two sulfobutylether-CDs showed efficacy with reduced ototoxicity. Complexation studies showed: incomplete correlation between CD efficacy and UC solubilization; an inverse correlation for ganglioside complexation; substantial interaction with several relevant lipids; and association between undesirable increases of UC storage in Kupffer cells and UC solubilization. INTERPRETATION CDs other than HPβCD identified here may provide disease amelioration without ototoxicity and merit long-term treatment studies. While direct interactions of CD-UC are thought central to the mechanism of correction, the data show that this does not strictly correlate with complexation ability and suggest interactions with other NPC disease-relevant substrates should be considered.
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Affiliation(s)
- Cristin D. Davidson
- Dominick P. Purpura Department of NeuroscienceRose F. Kennedy Center Intellectual and Developmental Disabilities Research CenterAlbert Einstein College of MedicineBronxNew York10461
| | - Yonatan I. Fishman
- Dominick P. Purpura Department of NeuroscienceRose F. Kennedy Center Intellectual and Developmental Disabilities Research CenterAlbert Einstein College of MedicineBronxNew York10461
| | - István Puskás
- CycloLab Cyclodextrin Research & Development Laboratory Ltd.BudapestH‐1097Hungary
| | - Julianna Szemán
- CycloLab Cyclodextrin Research & Development Laboratory Ltd.BudapestH‐1097Hungary
| | - Tamás Sohajda
- CycloLab Cyclodextrin Research & Development Laboratory Ltd.BudapestH‐1097Hungary
| | - Leslie A. McCauliff
- Department of Nutritional Sciences and Rutgers Center for Lipid ResearchRutgers UniversityNew BrunswickNew Jersey08901
| | - Jakub Sikora
- Dominick P. Purpura Department of NeuroscienceRose F. Kennedy Center Intellectual and Developmental Disabilities Research CenterAlbert Einstein College of MedicineBronxNew York10461
- Institute of Inherited Metabolic DisordersFirst Faculty of MedicineCharles University in Prague and General University Hospital in PraguePragueCzech Republic
| | - Judith Storch
- Department of Nutritional Sciences and Rutgers Center for Lipid ResearchRutgers UniversityNew BrunswickNew Jersey08901
| | - Marie T. Vanier
- Institut National de la Santé et de la Recherche MédicaleUnit 820; EA4611 Lyon‐1 UniversityLyonFrance
| | - Lajos Szente
- CycloLab Cyclodextrin Research & Development Laboratory Ltd.BudapestH‐1097Hungary
| | - Steven U. Walkley
- Dominick P. Purpura Department of NeuroscienceRose F. Kennedy Center Intellectual and Developmental Disabilities Research CenterAlbert Einstein College of MedicineBronxNew York10461
| | - Kostantin Dobrenis
- Dominick P. Purpura Department of NeuroscienceRose F. Kennedy Center Intellectual and Developmental Disabilities Research CenterAlbert Einstein College of MedicineBronxNew York10461
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127
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Selective normalisation of regional brain bis(monoacylglycero)phosphate in the mucopolysaccharidosis 1 (Hurler) mouse. Exp Neurol 2016; 277:68-75. [DOI: 10.1016/j.expneurol.2015.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 11/20/2022]
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128
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Abstract
Sulfatide is a 3-O-sulfated galactosylceramide that is abundantly expressed in the gastrointestinal tract, kidney, trachea, and particularly the central nervous system. Cellular sulfatide is mainly localized in the Golgi apparatus, cellular membrane, and lysosomes in cytosol. Since our earlier report showed that the influenza A virus specifically binds to sulfatide, we have investigated the roles of sulfatide in the influenza A virus lifecycle. The viral binding is independent of sialic acids, which function as virus receptors in virus attachment to the host cell surface. Sulfatide is recognized by the ectodomain of the viral envelope glycoprotein hemagglutinin (HA). Nascent HA is transported on the surface membrane of infected cells. The binding of HA with sulfatide on the cell surface induces apoptosis through potential loss of the mitochondrial membrane and nuclear translocation of apoptosis-inducing factor in mitochondria, where PB1-F2 peptide from the viral gene is accumulated. In the nucleus of infected cells, viral ribonucleoprotein (vRNP) complexes are formed from viral RNA genomes, viral nucleoprotein, and viral RNA polymerase subunits, and these complexes are selectively exported into cytosol through the nuclear membrane. The apoptosis significantly enhances the nuclear export of vRNP complexes, resulting in efficient formation of progeny viruses and facilitation of virus replication. At that time, activation of the Raf/mitogen-activated protein extracellular kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway through sulfatide is associated with virus replication. Our studies have demonstrated that sulfatide is not a viral receptor for virus infection, and that the binding of HA with sulfatide functions as an initiation switch for the formation of progeny viruses.
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Affiliation(s)
- Tadanobu Takahashi
- Department of Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka
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129
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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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Kornhuber J, Rhein C, Müller CP, Mühle C. Secretory sphingomyelinase in health and disease. Biol Chem 2016; 396:707-36. [PMID: 25803076 DOI: 10.1515/hsz-2015-0109] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/16/2015] [Indexed: 01/12/2023]
Abstract
Acid sphingomyelinase (ASM), a key enzyme in sphingolipid metabolism, hydrolyzes sphingomyelin to ceramide and phosphorylcholine. In mammals, the expression of a single gene, SMPD1, results in two forms of the enzyme that differ in several characteristics. Lysosomal ASM (L-ASM) is located within the lysosome, requires no additional Zn2+ ions for activation and is glycosylated mainly with high-mannose oligosaccharides. By contrast, the secretory ASM (S-ASM) is located extracellularly, requires Zn2+ ions for activation, has a complex glycosylation pattern and has a longer in vivo half-life. In this review, we summarize current knowledge regarding the physiology and pathophysiology of S-ASM, including its sources and distribution, molecular and cellular mechanisms of generation and regulation and relevant in vitro and in vivo studies. Polymorphisms or mutations of SMPD1 lead to decreased S-ASM activity, as detected in patients with Niemann-Pick disease B. Thus, lower serum/plasma activities of S-ASM are trait markers. No genetic causes of increased S-ASM activity have been identified. Instead, elevated activity is the result of enhanced release (e.g., induced by lipopolysaccharide and cytokine stimulation) or increased enzyme activation (e.g., induced by oxidative stress). Increased S-ASM activity in serum or plasma is a state marker of a wide range of diseases. In particular, high S-ASM activity occurs in inflammation of the endothelium and liver. Several studies have demonstrated a correlation between S-ASM activity and mortality induced by severe inflammatory diseases. Serial measurements of S-ASM reveal prolonged activation and, therefore, the measurement of this enzyme may also provide information on past inflammatory processes. Thus, S-ASM may be both a promising clinical chemistry marker and a therapeutic target.
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131
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Lu L, Pandey AK, Houseal MT, Mulligan MK. The Genetic Architecture of Murine Glutathione Transferases. PLoS One 2016; 11:e0148230. [PMID: 26829228 PMCID: PMC4734686 DOI: 10.1371/journal.pone.0148230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 01/14/2016] [Indexed: 12/17/2022] Open
Abstract
Glutathione S-transferase (GST) genes play a protective role against oxidative stress and may influence disease risk and drug pharmacokinetics. In this study, massive multiscalar trait profiling across a large population of mice derived from a cross between C57BL/6J (B6) and DBA2/J (D2)—the BXD family—was combined with linkage and bioinformatic analyses to characterize mechanisms controlling GST expression and to identify downstream consequences of this variation. Similar to humans, mice show a wide range in expression of GST family members. Variation in the expression of Gsta4, Gstt2, Gstz1, Gsto1, and Mgst3 is modulated by local expression QTLs (eQTLs) in several tissues. Higher expression of Gsto1 in brain and liver of BXD strains is strongly associated (P < 0.01) with inheritance of the B6 parental allele whereas higher expression of Gsta4 and Mgst3 in brain and liver, and Gstt2 and Gstz1 in brain is strongly associated with inheritance of the D2 parental allele. Allele-specific assays confirmed that expression of Gsto1, Gsta4, and Mgst3 are modulated by sequence variants within or near each gene locus. We exploited this endogenous variation to identify coexpression networks and downstream targets in mouse and human. Through a combined systems genetics approach, we provide new insight into the biological role of naturally occurring variants in GST genes.
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Affiliation(s)
- Lu Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38106, United States of America
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, 226001, China
| | - Ashutosh K. Pandey
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38106, United States of America
| | - M. Trevor Houseal
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38106, United States of America
| | - Megan K. Mulligan
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38106, United States of America
- * E-mail:
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132
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Castellanos-Castro S, Cerda-García-Rojas CM, Javier-Reyna R, Pais-Morales J, Chávez-Munguía B, Orozco E. Identification of the phospholipid lysobisphosphatidic acid in the protozoan Entamoeba histolytica: An active molecule in endocytosis. Biochem Biophys Rep 2015; 5:224-236. [PMID: 28955828 PMCID: PMC5600446 DOI: 10.1016/j.bbrep.2015.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 11/25/2015] [Accepted: 12/21/2015] [Indexed: 12/15/2022] Open
Abstract
Phospholipids are essential for vesicle fusion and fission and both are fundamental events for Entamoeba histolytica phagocytosis. Our aim was to identify the lysobisphosphatidic acid (LBPA) in trophozoites and investigate its cellular fate during endocytosis. LBPA was detected by TLC in a 0.5 Rf spot of total lipids, which co-migrated with the LBPA standard. The 6C4 antibody, against LBPA recognized phospholipids extracted from this spot. Reverse phase LC-ESI-MS and MS/MS mass spectrometry revealed six LBPA species of m/z 772.58–802.68. LBPA was associated to pinosomes and phagosomes. Intriguingly, during pinocytosis, whole cell fluorescence quantification showed that LBPA dropped 84% after 15 min incubation with FITC-Dextran, and after 60 min, it increased at levels close to steady state conditions. Similarly, during erythrophagocytosis, after 15 min, LBPA also dropped in 36% and increased after 60 and 90 min. EhRab7A protein appeared in some vesicles with LBPA in steady state conditions, but after phagocytosis co-localization of both molecules increased and in late phases of erythrophagocytosis they were found in huge phagosomes or multivesicular bodies with many intraluminal vacuoles, and surrounding ingested erythrocytes and phagosomes. The 6C4 and anti-EhADH (EhADH is an ALIX family protein) antibodies and Lysotracker merged in about 50% of the vesicles in steady state conditions and throughout phagocytosis. LBPA and EhADH were also inside huge phagosomes. These results demonstrated that E. histolytica LBPA is associated to pinosomes and phagosomes during endocytosis and suggested differences of LBPA requirements during pinocytosis and phagocytosis. LBPA is identified for the first time in the protozoan Entamoeba histolytica. LBPA is found in pinosomes and in 10–20 µm diameter phagosomes or multivesicular bodies. LBPA appeared associated with EhRab7A protein, a late endosomes marker. LBPA interacts with EhADH (an ALIX family protein) during phagocytosis.
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Affiliation(s)
- Silvia Castellanos-Castro
- Departamento de Infectómica y Patogénesis Molecular, Mexico.,Colegio de Ciencia y Tecnología, Universidad Autónoma de la Ciudad de México, Dr. García Diego 168, CP 06720, D.F. México, México
| | - Carlos M Cerda-García-Rojas
- Departamento de Química, Centro de Investigación y de Estudios Avanzados del IPN, Avenue IPN, 2508, CP 07360, D.F. México, México
| | | | | | | | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, Mexico
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Abstract
Lysosomes are acidic compartments filled with more than 60 different types of hydrolases. They mediate the degradation of extracellular particles from endocytosis and of intracellular components from autophagy. The digested products are transported out of the lysosome via specific catabolite exporters or via vesicular membrane trafficking. Lysosomes also contain more than 50 membrane proteins and are equipped with the machinery to sense nutrient availability, which determines the distribution, number, size, and activity of lysosomes to control the specificity of cargo flux and timing (the initiation and termination) of degradation. Defects in degradation, export, or trafficking result in lysosomal dysfunction and lysosomal storage diseases (LSDs). Lysosomal channels and transporters mediate ion flux across perimeter membranes to regulate lysosomal ion homeostasis, membrane potential, catabolite export, membrane trafficking, and nutrient sensing. Dysregulation of lysosomal channels underlies the pathogenesis of many LSDs and possibly that of metabolic and common neurodegenerative diseases.
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Affiliation(s)
- Haoxing Xu
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109;
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134
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Hernández-Corbacho MJ, Canals D, Adada MM, Liu M, Senkal CE, Yi JK, Mao C, Luberto C, Hannun YA, Obeid LM. Tumor Necrosis Factor-α (TNFα)-induced Ceramide Generation via Ceramide Synthases Regulates Loss of Focal Adhesion Kinase (FAK) and Programmed Cell Death. J Biol Chem 2015; 290:25356-73. [PMID: 26318452 DOI: 10.1074/jbc.m115.658658] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Indexed: 11/06/2022] Open
Abstract
Ceramide synthases (CerS1-CerS6), which catalyze the N-acylation of the (dihydro)sphingosine backbone to produce (dihydro)ceramide in both the de novo and the salvage or recycling pathway of ceramide generation, have been implicated in the control of programmed cell death. However, the regulation of the de novo pathway compared with the salvage pathway is not fully understood. In the current study, we have found that late accumulation of multiple ceramide and dihydroceramide species in MCF-7 cells treated with TNFα occurred by up-regulation of both pathways of ceramide synthesis. Nevertheless, fumonisin B1 but not myriocin was able to protect from TNFα-induced cell death, suggesting that ceramide synthase activity is crucial for the progression of cell death and that the pool of ceramide involved derives from the salvage pathway rather than de novo biosynthesis. Furthermore, compared with control cells, TNFα-treated cells exhibited reduced focal adhesion kinase and subsequent plasma membrane permeabilization, which was blocked exclusively by fumonisin B1. In addition, exogenously added C6-ceramide mimicked the effects of TNFα that lead to cell death, which were inhibited by fumonisin B1. Knockdown of individual ceramide synthases identified CerS6 and its product C16-ceramide as the ceramide synthase isoform essential for the regulation of cell death. In summary, our data suggest a novel role for CerS6/C16-ceramide as an upstream effector of the loss of focal adhesion protein and plasma membrane permeabilization, via the activation of caspase-7, and identify the salvage pathway as the critical mechanism of ceramide generation that controls cell death.
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Affiliation(s)
| | - Daniel Canals
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Mohamad M Adada
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Mengling Liu
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Can E Senkal
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Jae Kyo Yi
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Cungui Mao
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Chiara Luberto
- From the Stony Brook Cancer Center, the Department of Physiology and Biophysics, Stony Brook University, Health Sciences Center, Stony Brook, New York 11794 and
| | - Yusuf A Hannun
- From the Stony Brook Cancer Center, the Department of Medicine, and
| | - Lina M Obeid
- From the Stony Brook Cancer Center, the Department of Medicine, and the Northport Veterans Affairs Medical Center, Northport, New York 11768
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135
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Wronowska W, Charzyńska A, Nienałtowski K, Gambin A. Computational modeling of sphingolipid metabolism. BMC SYSTEMS BIOLOGY 2015; 9:47. [PMID: 26275400 PMCID: PMC4537549 DOI: 10.1186/s12918-015-0176-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 06/05/2015] [Indexed: 12/13/2022]
Abstract
Background As suggested by the origin of the word, sphingolipids are mysterious molecules with various roles in antagonistic cellular processes such as autophagy, apoptosis, proliferation and differentiation. Moreover, sphingolipids have recently been recognized as important messengers in cellular signaling pathways. Notably, sphingolipid metabolism disorders have been observed in various pathological conditions such as cancer and neurodegeneration. Results The existing formal models of sphingolipid metabolism focus mainly on de novo ceramide synthesis or are limited to biochemical transformations of particular subspecies. Here, we propose the first comprehensive computational model of sphingolipid metabolism in human tissue. Contrary to the previous approaches, we use a model that reflects cell compartmentalization thereby highlighting the differences among individual organelles. Conclusions The model that we present here was validated using recently proposed methods of model analysis, allowing to detect the most sensitive and experimentally non-identifiable parameters and determine the main sources of model variance. Moreover, we demonstrate the usefulness of our model in the study of molecular processes underlying Alzheimer’s disease, which are associated with sphingolipid metabolism. Electronic supplementary material The online version of this article (doi:10.1186/s12918-015-0176-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Weronika Wronowska
- Institute of Computer Science Polish Academy of Sciences, Warsaw, Poland.
| | - Agata Charzyńska
- Faculty of Biology University of Warsaw, Warsaw, Poland. .,Bioinformatics Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.
| | - Karol Nienałtowski
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland.
| | - Anna Gambin
- Institute of Informatics, University of Warsaw, Warsaw, Poland.
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136
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Zajonc DM, Girardi E. Recognition of Microbial Glycolipids by Natural Killer T Cells. Front Immunol 2015; 6:400. [PMID: 26300885 PMCID: PMC4523824 DOI: 10.3389/fimmu.2015.00400] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 07/21/2015] [Indexed: 11/18/2022] Open
Abstract
T cells can recognize microbial antigens when presented by dedicated antigen-presenting molecules. While peptides are presented by classical members of the major histocompatibility complex (MHC) family (MHC I and II), lipids, glycolipids, and lipopeptides can be presented by the non-classical MHC member, CD1. The best studied subset of lipid-reactive T cells are type I natural killer T (iNKT) cells that recognize a variety of different antigens when presented by the non-classical MHCI homolog CD1d. iNKT cells have been shown to be important for the protection against various microbial pathogens, including B. burgdorferi, the causative agents of Lyme disease, and S. pneumoniae, which causes pneumococcal meningitis and community-acquired pneumonia. Both pathogens carry microbial glycolipids that can trigger the T cell antigen receptor (TCR), leading to iNKT cell activation. iNKT cells have an evolutionary conserved TCR alpha chain, yet retain the ability to recognize structurally diverse glycolipids. They do so using a conserved recognition mode, in which the TCR enforces a conserved binding orientation on CD1d. TCR binding is accompanied by structural changes within the TCR binding site of CD1d, as well as the glycolipid antigen itself. In addition to direct recognition of microbial antigens, iNKT cells can also be activated by a combination of cytokines (IL-12/IL-18) and TCR stimulation. Many microbes carry TLR antigens, and microbial infections can lead to TLR activation. The subsequent cytokine response in turn lower the threshold of TCR-mediated iNKT cell activation, especially when weak microbial or even self-antigens are presented during the cause of the infection. In summary, iNKT cells can be directly activated through TCR triggering of strong antigens, while cytokines produced by the innate immune response may be necessary for TCR triggering and iNKT cell activation in the presence of weak antigens. Here, we will review the molecular basis of iNKT cell recognition of glycolipids, with an emphasis on microbial glycolipids.
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Affiliation(s)
- Dirk M Zajonc
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA
| | - Enrico Girardi
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA
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137
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Hill CH, Read RJ, Deane JE. Structure of human saposin A at lysosomal pH. ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2015; 71:895-900. [PMID: 26144235 PMCID: PMC4498711 DOI: 10.1107/s2053230x15008584] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 05/01/2015] [Indexed: 11/10/2022]
Abstract
The saposins are essential cofactors for the normal lysosomal degradation of complex glycosphingolipids by acid hydrolase enzymes; defects in either saposin or hydrolase function lead to severe metabolic diseases. Saposin A (SapA) activates the enzyme β-galactocerebrosidase (GALC), which catalyzes the breakdown of β-D-galactocerebroside, the principal lipid component of myelin. SapA is known to bind lipids and detergents in a pH-dependent manner; this is accompanied by a striking transition from a `closed' to an `open' conformation. However, previous structures were determined at non-lysosomal pH. This work describes a 1.8 Å resolution X-ray crystal structure determined at the physiologically relevant lysosomal pH 4.8. In the absence of lipid or detergent at pH 4.8, SapA is observeed to adopt a conformation closely resembling the previously determined `closed' conformation, showing that pH alone is not sufficient for the transition to the `open' conformation. Structural alignments reveal small conformational changes, highlighting regions of flexibility.
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Affiliation(s)
- Chris H Hill
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
| | - Randy J Read
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
| | - Janet E Deane
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
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138
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Imaging and Therapy of Pancreatic Cancer with Phosphatidylserine-Targeted Nanovesicles. Transl Oncol 2015; 8:196-203. [PMID: 26055177 PMCID: PMC4486738 DOI: 10.1016/j.tranon.2015.03.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 03/09/2015] [Accepted: 03/17/2015] [Indexed: 12/12/2022] Open
Abstract
Pancreatic cancer remains one of the most intractable cancers, with a dismal prognosis reflected by a 5-year survival of ~6%. Since early disease symptoms are undefined and specific biomarkers are lacking, about 80% of patients present with advanced, inoperable tumors that represent a daunting challenge. Despite many clinical trials, no single chemotherapy agent has been reliably associated with objective response rates above 10% or median survival longer than 5 to 7 months. Although combination chemotherapy regimens have in recent years provided some improvement, overall survival (8-11 months) remains very poor. There is therefore a critical need for novel therapies that can improve outcomes for pancreatic cancer patients. Here, we present a summary of the current therapies used in the management of advanced pancreatic cancer and review novel therapeutic strategies that target tumor biomarkers. We also describe our recent research using phosphatidylserine-targeted saposin C-coupled dioleoylphosphatidylserine nanovesicles for imaging and therapy of pancreatic cancer.
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139
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Akgoc Z, Sena-Esteves M, Martin DR, Han X, d'Azzo A, Seyfried TN. Bis(monoacylglycero)phosphate: a secondary storage lipid in the gangliosidoses. J Lipid Res 2015; 56:1006-13. [PMID: 25795792 DOI: 10.1194/jlr.m057851] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Indexed: 01/24/2023] Open
Abstract
Bis(monoacylglycero)phosphate (BMP) is a negatively charged glycerophospholipid with an unusual sn-1;sn-1' structural configuration. BMP is primarily enriched in endosomal/lysosomal membranes. BMP is thought to play a role in glycosphingolipid degradation and cholesterol transport. Elevated BMP levels have been found in many lysosomal storage diseases (LSDs), suggesting an association with lysosomal storage material. The gangliosidoses are a group of neurodegenerative LSDs involving the accumulation of either GM1 or GM2 gangliosides resulting from inherited deficiencies in β-galactosidase or β-hexosaminidase, respectively. Little information is available on BMP levels in gangliosidosis brain tissue. Our results showed that the content of BMP in brain was significantly greater in humans and in animals (mice, cats, American black bears) with either GM1 or GM2 ganglioside storage diseases, than in brains of normal subjects. The storage of BMP and ganglioside GM2 in brain were reduced similarly following adeno-associated viral-mediated gene therapy in Sandhoff disease mice. We also found that C22:6, C18:0, and C18:1 were the predominant BMP fatty acid species in gangliosidosis brains. The results show that BMP accumulates as a secondary storage material in the brain of a broad range of mammals with gangliosidoses.
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Affiliation(s)
- Zeynep Akgoc
- Department of Biology, Boston College, Chestnut Hill, MA 02467
| | - Miguel Sena-Esteves
- Department of Neurology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605
| | - Douglas R Martin
- Scott-Ritchey Research Center and Department of Anatomy, Physiology, and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849
| | - Xianlin Han
- Sanford-Burnham Medical Research Institute, Orlando, FL 32827
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140
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Gruschus JM, Jiang Z, Yap TL, Hill SA, Grishaev A, Piszczek G, Sidransky E, Lee JC. Dissociation of glucocerebrosidase dimer in solution by its co-factor, saposin C. Biochem Biophys Res Commun 2015; 457:561-6. [PMID: 25600808 DOI: 10.1016/j.bbrc.2015.01.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 01/08/2015] [Indexed: 12/23/2022]
Abstract
Mutations in the gene for the lysosomal enzyme glucocerebrosidase (GCase) cause Gaucher disease and are the most common risk factor for Parkinson disease (PD). Analytical ultracentrifugation of 8 μM GCase shows equilibrium between monomer and dimer forms. However, in the presence of its co-factor saposin C (Sap C), only monomer GCase is seen. Isothermal calorimetry confirms that Sap C associates with GCase in solution in a 1:1 complex (Kd = 2.1 ± 1.1 μM). Saturation cross-transfer NMR determined that the region of Sap C contacting GCase includes residues 63-66 and 74-76, which is distinct from the region known to enhance GCase activity. Because α-synuclein (α-syn), a protein closely associated with PD etiology, competes with Sap C for GCase binding, its interaction with GCase was also measured by ultracentrifugation and saturation cross-transfer. Unlike Sap C, binding of α-syn to GCase does not affect multimerization. However, adding α-syn reduces saturation cross-transfer from Sap C to GCase, confirming displacement. To explore where Sap C might disrupt multimeric GCase, GCase x-ray structures were analyzed using the program PISA, which predicted stable dimer and tetramer forms. For the most frequently predicted multimer interface, the GCase active sites are partially buried, suggesting that Sap C might disrupt the multimer by binding near the active site.
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Affiliation(s)
- James M Gruschus
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD 20892, United States.
| | - Zhiping Jiang
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD 20892, United States
| | - Thai Leong Yap
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD 20892, United States
| | - Stephanie A Hill
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD 20892, United States
| | - Alexander Grishaev
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, United States
| | - Grzegorz Piszczek
- Biophysics Core, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Ellen Sidransky
- Section on Molecular Neurogenetics, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Jennifer C Lee
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD 20892, United States.
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141
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Sato K, Kitakaze K, Nakamura T, Naruse N, Aihara K, Shigenaga A, Inokuma T, Tsuji D, Itoh K, Otaka A. The total chemical synthesis of the monoglycosylated GM2 ganglioside activator using a novel cysteine surrogate. Chem Commun (Camb) 2015; 51:9946-8. [DOI: 10.1039/c5cc02967h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We describe a novel peptide ligation/desulfurization strategy using a β-mercapto-N-glycosylated asparagine derivative. The strategy is successfully applied to the total chemical synthesis of GM2 ganglioside activator protein.
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Affiliation(s)
- Kohei Sato
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Keisuke Kitakaze
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Takahiro Nakamura
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Naoto Naruse
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Keisuke Aihara
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Akira Shigenaga
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Tsubasa Inokuma
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Daisuke Tsuji
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Kohji Itoh
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
| | - Akira Otaka
- Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences
- Tokushima University
- Tokushima 770-8505
- Japan
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142
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Watanabe T, Ishibashi Y, Ito M. Physiological Significance of Glycolipid Catabolism in Cryptococcus neoformans. TRENDS GLYCOSCI GLYC 2015. [DOI: 10.4052/tigg.1504.1e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Takashi Watanabe
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
| | - Yohei Ishibashi
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
| | - Makoto Ito
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
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143
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Watanabe T, Ishibashi Y, Ito M. Physiological Significance of Glycolipid Catabolism in Cryptococcus neoformans (Jpn. Ed.). TRENDS GLYCOSCI GLYC 2015. [DOI: 10.4052/tigg.1504.1j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Takashi Watanabe
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
| | - Yohei Ishibashi
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
| | - Makoto Ito
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University
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144
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Yap TL, Jiang Z, Heinrich F, Gruschus JM, Pfefferkorn CM, Barros M, Curtis JE, Sidransky E, Lee JC. Structural features of membrane-bound glucocerebrosidase and α-synuclein probed by neutron reflectometry and fluorescence spectroscopy. J Biol Chem 2014; 290:744-54. [PMID: 25429104 DOI: 10.1074/jbc.m114.610584] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in glucocerebrosidase (GCase), the enzyme deficient in Gaucher disease, are a common genetic risk factor for the development of Parkinson disease and related disorders, implicating the role of this lysosomal hydrolase in the disease etiology. A specific physical interaction exists between the Parkinson disease-related protein α-synuclein (α-syn) and GCase both in solution and on the lipid membrane, resulting in efficient enzyme inhibition. Here, neutron reflectometry was employed as a first direct structural characterization of GCase and α-syn·GCase complex on a sparsely-tethered lipid bilayer, revealing the orientation of the membrane-bound GCase. GCase binds to and partially inserts into the bilayer with its active site most likely lying just above the membrane-water interface. The interaction was further characterized by intrinsic Trp fluorescence, circular dichroism, and surface plasmon resonance spectroscopy. Both Trp fluorescence and neutron reflectometry results suggest a rearrangement of loops surrounding the catalytic site, where they extend into the hydrocarbon chain region of the outer leaflet. Taking advantage of contrasting neutron scattering length densities, the use of deuterated α-syn versus protiated GCase showed a large change in the membrane-bound structure of α-syn in the complex. We propose a model of α-syn·GCase on the membrane, providing structural insights into inhibition of GCase by α-syn. The interaction displaces GCase away from the membrane, possibly impeding substrate access and perturbing the active site. GCase greatly alters membrane-bound α-syn, moving helical residues away from the bilayer, which could impact the degradation of α-syn in the lysosome where these two proteins interact.
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Affiliation(s)
| | - Zhiping Jiang
- From the Laboratory of Molecular Biophysics, NHLBI, and
| | - Frank Heinrich
- the Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and the Center for Neutron Research, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | | | | | - Marilia Barros
- the Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and
| | - Joseph E Curtis
- the Center for Neutron Research, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Ellen Sidransky
- the Medical Genetics Branch, NHGRI, National Institutes of Health, Bethesda, Maryland 20892
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145
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Bai A, Szulc ZM, Bielawski J, Pierce JS, Rembiesa B, Terzieva S, Mao C, Xu R, Wu B, Clarke CJ, Newcomb B, Liu X, Norris J, Hannun YA, Bielawska A. Targeting (cellular) lysosomal acid ceramidase by B13: design, synthesis and evaluation of novel DMG-B13 ester prodrugs. Bioorg Med Chem 2014; 22:6933-44. [PMID: 25456083 DOI: 10.1016/j.bmc.2014.10.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 10/06/2014] [Accepted: 10/15/2014] [Indexed: 11/29/2022]
Abstract
Acid ceramidase (ACDase) is being recognized as a therapeutic target for cancer. B13 represents a moderate inhibitor of ACDase. The present study concentrates on the lysosomal targeting of B13 via its N,N-dimethylglycine (DMG) esters (DMG-B13 prodrugs). Novel analogs, the isomeric mono-DMG-B13, LCL522 (3-O-DMG-B13·HCl) and LCL596 (1-O-DMG-B13·HCl) and di-DMG-B13, LCL521 (1,3-O, O-DMG-B13·2HCl) conjugates, were designed and synthesized through N,N-dimethyl glycine (DMG) esterification of the hydroxyl groups of B13. In MCF7 cells, DMG-B13 prodrugs were efficiently metabolized to B13. The early inhibitory effect of DMG-B13 prodrugs on cellular ceramidases was ACDase specific by their lysosomal targeting. The corresponding dramatic decrease of cellular Sph (80-97% Control/1h) by DMG-B13 prodrugs was mainly from the inhibition of the lysosomal ACDase.
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Affiliation(s)
- Aiping Bai
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Zdzislaw M Szulc
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Jacek Bielawski
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Jason S Pierce
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Barbara Rembiesa
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Silva Terzieva
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Cungui Mao
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Ruijuan Xu
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Bill Wu
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Christopher J Clarke
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Benjamin Newcomb
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Xiang Liu
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - James Norris
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Yusuf A Hannun
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA.
| | - Alicja Bielawska
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA.
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146
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Zhu H, Yoshimoto T, Yamashima T. Heat shock protein 70.1 (Hsp70.1) affects neuronal cell fate by regulating lysosomal acid sphingomyelinase. J Biol Chem 2014; 289:27432-43. [PMID: 25074941 PMCID: PMC4183783 DOI: 10.1074/jbc.m114.560334] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 07/18/2014] [Indexed: 12/17/2022] Open
Abstract
The inducible expression of heat shock protein 70.1 (Hsp70.1) plays cytoprotective roles in its molecular chaperone function. Binding of Hsp70 to an endolysosomal phospholipid, bis(monoacylglycero)phosphate (BMP), has been recently shown to stabilize lysosomal membranes by enhancing acid sphingomyelinase (ASM) activity in cancer cells. Using the monkey experimental paradigm, we have reported that calpain-mediated cleavage of oxidized Hsp70.1 causes neurodegeneration in the hippocampal cornu ammonis 1 (CA1), whereas expression of Hsp70.1 in the motor cortex without calpain activation contributes to neuroprotection. However, the molecular mechanisms of the lysosomal destabilization/stabilization determining neuronal cell fate have not been elucidated. To elucidate whether regulation of lysosomal ASM could affect the neuronal fate, we analyzed Hsp70.1-BMP binding and ASM activity by comparing the motor cortex and the CA1. We show that Hsp70.1 being localized at the lysosomal membrane, lysosomal lipid BMP levels, and the lipid binding domain of Hsp70.1 are crucial for Hsp70.1-BMP binding. In the postischemic motor cortex, Hsp70.1 being localized at the lysosomal membrane could bind to BMP without calpain activation and decreased BMP levels, resulting in increasing ASM activity and lysosomal stability. However, in the postischemic CA1, calpain activation and a concomitant decrease in the lysosomal membrane localization of Hsp70.1 and BMP levels may diminish Hsp70.1-BMP binding, resulting in decreased ASM activity and lysosomal rupture with leakage of cathepsin B into the cytosol. A TUNEL assay revealed the differential neuronal vulnerability between the CA1 and the motor cortex. These results suggest that regulation of ASM activation in vivo by Hsp70.1-BMP affects lysosomal stability and neuronal survival or death after ischemia/reperfusion.
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Affiliation(s)
- Hong Zhu
- From the Departments of Restorative Neurosurgery, Molecular Pharmacology, and
| | | | - Tetsumori Yamashima
- From the Departments of Restorative Neurosurgery, Psychiatry and Neurobiology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa, Japan
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147
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Sarbu M, Robu A, Peter-Katalinić J, Zamfir AD. Automated chip-nanoelectrospray mass spectrometry for glycourinomics in Schindler disease type I. Carbohydr Res 2014; 398:90-100. [DOI: 10.1016/j.carres.2014.08.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/19/2014] [Accepted: 08/21/2014] [Indexed: 12/16/2022]
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148
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Fateen EM, Gouda AS, Ibrahim MM, Abdallah ZY. Fifteen years experience: Egyptian metabolic lab. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2014. [DOI: 10.1016/j.ejmhg.2014.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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149
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Yang DS, Stavrides P, Saito M, Kumar A, Rodriguez-Navarro JA, Pawlik M, Huo C, Walkley SU, Saito M, Cuervo AM, Nixon RA. Defective macroautophagic turnover of brain lipids in the TgCRND8 Alzheimer mouse model: prevention by correcting lysosomal proteolytic deficits. ACTA ACUST UNITED AC 2014; 137:3300-18. [PMID: 25270989 DOI: 10.1093/brain/awu278] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Autophagy, the major lysosomal pathway for the turnover of intracellular organelles is markedly impaired in neurons in Alzheimer's disease and Alzheimer mouse models. We have previously reported that severe lysosomal and amyloid neuropathology and associated cognitive deficits in the TgCRND8 Alzheimer mouse model can be ameliorated by restoring lysosomal proteolytic capacity and autophagy flux via genetic deletion of the lysosomal protease inhibitor, cystatin B. Here we present evidence that macroautophagy is a significant pathway for lipid turnover, which is defective in TgCRND8 brain where lipids accumulate as membranous structures and lipid droplets within giant neuronal autolysosomes. Levels of multiple lipid species including several sphingolipids (ceramide, ganglioside GM3, GM2, GM1, GD3 and GD1a), cardiolipin, cholesterol and cholesteryl esters are elevated in autophagic vacuole fractions and lysosomes isolated from TgCRND8 brain. Lipids are localized in autophagosomes and autolysosomes by double immunofluorescence analyses in wild-type mice and colocalization is increased in TgCRND8 mice where abnormally abundant GM2 ganglioside-positive granules are detected in neuronal lysosomes. Cystatin B deletion in TgCRND8 significantly reduces the number of GM2-positive granules and lowers the levels of GM2 and GM3 in lysosomes, decreases lipofuscin-related autofluorescence, and eliminates giant lipid-containing autolysosomes while increasing numbers of normal-sized autolysosomes/lysosomes with reduced content of undigested components. These findings have identified macroautophagy as a previously unappreciated route for delivering membrane lipids to lysosomes for turnover, a function that has so far been considered to be mediated exclusively through the endocytic pathway, and revealed that autophagic-lysosomal dysfunction in TgCRND8 brain impedes lysosomal turnover of lipids as well as proteins. The amelioration of lipid accumulation in TgCRND8 by removing cystatin B inhibition on lysosomal proteases suggests that enhancing lysosomal proteolysis improves the overall environment of the lysosome and its clearance functions, which may be possibly relevant to a broader range of lysosomal disorders beyond Alzheimer's disease.
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Affiliation(s)
- Dun-Sheng Yang
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA 2 Department of Psychiatry, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA
| | - Philip Stavrides
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA
| | - Mitsuo Saito
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA 2 Department of Psychiatry, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA
| | - Asok Kumar
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA 2 Department of Psychiatry, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA
| | - Jose A Rodriguez-Navarro
- 3 Department of Developmental and Molecular Biology, Institute for Ageing Studies, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Monika Pawlik
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA
| | - Chunfeng Huo
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA
| | - Steven U Walkley
- 4 Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Mariko Saito
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA 2 Department of Psychiatry, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA
| | - Ana M Cuervo
- 3 Department of Developmental and Molecular Biology, Institute for Ageing Studies, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Ralph A Nixon
- 1 Centre for Dementia Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA 2 Department of Psychiatry, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA 5 Department of Cell Biology, New York University Langone Medical Centre, 550 First Avenue, New York, NY 10016, USA
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150
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PKG and NHR-49 signalling co-ordinately regulate short-term fasting-induced lysosomal lipid accumulation in C. elegans. Biochem J 2014; 461:509-20. [PMID: 24854345 DOI: 10.1042/bj20140191] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Lysosomes act as terminal degradation organelles to hydrolyse macromolecules derived from both the extracellular space and the cytoplasm. In Caenorhabditis elegans fasting induces the lysosomal compartment to expand. However, the molecular and cellular mechanisms for this stress response remain largely unclear. In the present study, we find that short-term fasting leads to increased accumulation of polar lipids in lysosomes. The fasting response is co-ordinately regulated by EGL-4, the C. elegans PKG (protein kinase G) orthologue, and nuclear hormone receptor NHR-49. Further results demonstrate that EGL-4 acts in sensory neurons to enhance lysosomal lipid accumulation through inhibiting the DAF-3/SMAD pathway, whereas NHR-49 acts in intestine to inhibit lipids accumulation via activation of IPLA-2 (intracellular membrane-associated calcium-independent phospholipase A2) in cytoplasm and other hydrolases in lysosomes. Remarkably, the lysosomal lipid accumulation is independent of autophagy and RAB-7-mediated endocytosis. Taken together, our results reveal a new mechanism for lysosomal lipid metabolism during the stress response, which may provide new clues for investigations of lysosome function in energy homoeostasis.
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