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Nakashima K, Hirahara Y, Koike T, Tanaka S, Gamo K, Oe S, Hayashi S, Seki-Omura R, Nakano Y, Ohe C, Yoshida T, Kataoka Y, Tsuda M, Yamashita T, Honke K, Kitada M. Sulfatide with ceramide composed of phytosphingosine (t18:0) and 2-hydroxy fatty acids in renal intercalated cells. J Lipid Res 2022; 63:100210. [PMID: 35439525 PMCID: PMC9157219 DOI: 10.1016/j.jlr.2022.100210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/28/2022] [Accepted: 04/10/2022] [Indexed: 11/27/2022] Open
Abstract
Diverse molecular species of sulfatide with differences in FA lengths, unsaturation degrees, and hydroxylation statuses are expressed in the kidneys. However, the physiological functions of specific sulfatide species in the kidneys are unclear. Here, we evaluated the distribution of specific sulfatide species in the kidneys and their physiological functions. Electron microscopic analysis of kidneys of Cst-deficient mice lacking sulfatide showed vacuolar accumulation in the cytoplasm of intercalated cells in the collecting duct, whereas the proximal and distal tubules were unchanged. Immunohistochemical analysis revealed that vacuolar H+-ATPase-positive vesicles were accumulated in intercalated cells in sulfatide-deficient kidneys. Seventeen sulfatide species were detected in the murine kidney by iMScope MALDI-MS analysis. The distribution of the specific sulfatide species was classified into four patterns. Although most sulfatide species were highly expressed in the outer medullary layer, two unique sulfatide species of m/z 896.6 (predicted ceramide structure: t18:0-C22:0h) and m/z 924.6 (predicted ceramide structure: t18:0-C24:0h) were dispersed along the collecting duct, implying expression in intercalated cells. In addition, the intercalated cell-enriched fraction was purified by fluorescence-activated cell sorting using the anti-vacuolar H+-ATPase subunit 6V0A4, which predominantly contained sulfatide species (m/z 896.6 and 924.6). The Degs2 and Fa2h genes, which are responsible for ceramide hydroxylation, were expressed in the purified intercalated cells. These results suggested that sulfatide molecular species with ceramide composed of phytosphingosine (t18:0) and 2-hydroxy FAs, which were characteristically expressed in intercalated cells, were involved in the excretion of NH3 and protons into the urine.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Takashi Yoshida
- Department of Urology and Andrology, Kansai Medical University, Hirakata, Osaka, Japan
| | - Yosky Kataoka
- Laboratory for Cellular Function Imaging, RIKEN Center for Biosystems Dynamics Research; Multi-Modal Microstructure Analysis Unit, RIKEN-JEOL Collaboration Center, Kobe, Hyogo, Japan
| | | | - Tatsuyuki Yamashita
- Department of Biochemistry, Kochi University Medical School, Nangoku, Kochi, Japan
| | - Koichi Honke
- Department of Biochemistry, Kochi University Medical School, Nangoku, Kochi, Japan
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2
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Li Q, Bozek K, Xu C, Guo Y, Sun J, Pääbo S, Sherwood CC, Hof PR, Ely JJ, Li Y, Willmitzer L, Giavalisco P, Khaitovich P. Changes in Lipidome Composition during Brain Development in Humans, Chimpanzees, and Macaque Monkeys. Mol Biol Evol 2017; 34:1155-1166. [PMID: 28158622 PMCID: PMC5400384 DOI: 10.1093/molbev/msx065] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Lipids are essential components of the brain. Here, we conducted a comprehensive mass spectrometry-based analysis of lipidome composition in the prefrontal cortex of 40 humans, 40 chimpanzees, and 40 rhesus monkeys over postnatal development and adulthood. Of the 11,772 quantified lipid peaks, 7,589 change significantly along the lifespan. More than 60% of these changes occur prior to adulthood, with less than a quarter associated with myelination progression. Evolutionarily, 36% of the age-dependent lipids exhibit concentration profiles distinct to one of the three species; 488 (18%) of them were unique to humans. In both humans and chimpanzees, the greatest extent of species-specific differences occurs in early development. Human-specific lipidome differences, however, persist over most of the lifespan and reach their peak from 20 to 35 years of age, when compared with chimpanzee-specific ones.
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Affiliation(s)
- Qian Li
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for Biological Sciences, CAS, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | | | - Chuan Xu
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for Biological Sciences, CAS, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yanan Guo
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for Biological Sciences, CAS, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jing Sun
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for Biological Sciences, CAS, Shanghai, China
| | - Svante Pääbo
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | | | - Yan Li
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Lothar Willmitzer
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | | | - Philipp Khaitovich
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for Biological Sciences, CAS, Shanghai, China.,Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Skoltech Center for Computational and Systems Biology, Skolkovo Institute for Science and Technology, Skolkovo, Russia
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3
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Hirahara Y, Wakabayashi T, Mori T, Koike T, Yao I, Tsuda M, Honke K, Gotoh H, Ono K, Yamada H. Sulfatide species with various fatty acid chains in oligodendrocytes at different developmental stages determined by imaging mass spectrometry. J Neurochem 2016; 140:435-450. [PMID: 27861899 DOI: 10.1111/jnc.13897] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/27/2016] [Accepted: 10/19/2016] [Indexed: 12/21/2022]
Abstract
HSO3-3-galactosylceramide (Sulfatide) species comprise the major glycosphingolipid components of oligodendrocytes and myelin and play functional roles in the regulation of oligodendrocyte maturation and myelin formation. Although various sulfatide species contain different fatty acids, it is unclear how these sulfatide species affect oligodendrogenesis and myelination. The O4 monoclonal antibody reaction with sulfatide has been widely used as a useful marker for oligodendrocytes and myelin. However, sulfatide synthesis during the pro-oligodendroblast stage, where differentiation into the oligodendrocyte lineage has already occurred, has not been examined. Notably, this stage comprises O4-positive cells. In this study, we identified a sulfatide species from the pro-oligodendroblast-to-myelination stage by imaging mass spectrometry. The results demonstrated that short-chain sulfatides with 16 carbon non-hydroxylated fatty acids (C16) and 18 carbon non-hydroxylated fatty acids (C18) or 18 carbon hydroxylated fatty acids (C18-OH) existed in restricted regions of the early embryonic spinal cord, where pro-oligodendroblasts initially appear, and co-localized with Olig2-positive pro-oligodendroblasts. C18 and C18-OH sulfatides also existed in isolated pro-oligodendroblasts. C22-OH sulfatide became predominant later in oligodendrocyte development and the longer C24 sulfatide was predominant in the adult brain. Additionally, the presence of each sulfatide species in a different area of the adult brain was demonstrated by imaging mass spectrometry at an increased lateral resolution. These findings indicated that O4 recognized sulfatides with short-chain fatty acids in pro-oligodendroblasts. Moreover, the fatty acid chain of the sulfatide became longer as the oligodendrocyte matured. Therefore, individual sulfatide species may have unique roles in oligodendrocyte maturation and myelination. Read the Editorial Highlight for this article on page 356.
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Affiliation(s)
- Yukie Hirahara
- Department of Anatomy and Cell Science, Kansai Medical University, Osaka, Japan
| | | | - Tetsuji Mori
- Department of Anatomy and Cell Science, Kansai Medical University, Osaka, Japan.,School of Health Science, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Taro Koike
- Department of Anatomy and Cell Science, Kansai Medical University, Osaka, Japan
| | - Ikuko Yao
- Department of Optical Imaging, Institute for Medical Photonics Research, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, Shizuoka, Japan
| | - Masayuki Tsuda
- The Division of Laboratory Animal Science, Science Research Center, Kochi University Medical School, Kochi, Japan
| | - Koichi Honke
- Department of Biochemistry, Kochi University Medical School, Kochi, Japan
| | - Hitoshi Gotoh
- Department of Biology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Katsuhiko Ono
- Department of Biology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hisao Yamada
- Department of Anatomy and Cell Science, Kansai Medical University, Osaka, Japan
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Role of galactosylceramide and sulfatide in oligodendrocytes and CNS myelin: formation of a glycosynapse. ADVANCES IN NEUROBIOLOGY 2014; 9:263-91. [PMID: 25151383 DOI: 10.1007/978-1-4939-1154-7_12] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The two major glycosphingolipids of myelin, galactosylceramide (GalC) and sulfatide (SGC), interact with each other by trans carbohydrate-carbohydrate interactions in vitro. They face each other in the apposed extracellular surfaces of the multilayered myelin sheath produced by oligodendrocytes and could also contact each other between apposed oligodendrocyte processes. Multivalent galactose and sulfated galactose, in the form of GalC/SGC-containing liposomes or silica nanoparticles conjugated to galactose and galactose-3-sulfate, interact with GalC and SGC in the membrane sheets of oligodendrocytes in culture. This interaction causes transmembrane signaling, loss of the cytoskeleton and clustering of membrane domains, similar to the effects of cross-linking by anti-GalC and anti-SGC antibodies. These effects suggest that GalC and SGC could participate in glycosynapses, similar to neural synapses or the immunological synapse, between GSL-enriched membrane domains in apposed oligodendrocyte membranes or extracellular surfaces of mature myelin. Formation of such glycosynapses in vivo would be important for myelination and/or oligodendrocyte/myelin function.
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5
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Harauz G, Boggs JM. Myelin management by the 18.5-kDa and 21.5-kDa classic myelin basic protein isoforms. J Neurochem 2013; 125:334-61. [PMID: 23398367 DOI: 10.1111/jnc.12195] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 02/05/2013] [Accepted: 02/05/2013] [Indexed: 12/15/2022]
Abstract
The classic myelin basic protein (MBP) splice isoforms range in nominal molecular mass from 14 to 21.5 kDa, and arise from the gene in the oligodendrocyte lineage (Golli) in maturing oligodendrocytes. The 18.5-kDa isoform that predominates in adult myelin adheres the cytosolic surfaces of oligodendrocyte membranes together, and forms a two-dimensional molecular sieve restricting protein diffusion into compact myelin. However, this protein has additional roles including cytoskeletal assembly and membrane extension, binding to SH3-domains, participation in Fyn-mediated signaling pathways, sequestration of phosphoinositides, and maintenance of calcium homeostasis. Of the diverse post-translational modifications of this isoform, phosphorylation is the most dynamic, and modulates 18.5-kDa MBP's protein-membrane and protein-protein interactions, indicative of a rich repertoire of functions. In developing and mature myelin, phosphorylation can result in microdomain or even nuclear targeting of the protein, supporting the conclusion that 18.5-kDa MBP has significant roles beyond membrane adhesion. The full-length, early-developmental 21.5-kDa splice isoform is predominantly karyophilic due to a non-traditional P-Y nuclear localization signal, with effects such as promotion of oligodendrocyte proliferation. We discuss in vitro and recent in vivo evidence for multifunctionality of these classic basic proteins of myelin, and argue for a systematic evaluation of the temporal and spatial distributions of these protein isoforms, and their modified variants, during oligodendrocyte differentiation.
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Affiliation(s)
- George Harauz
- Department of Molecular and Cellular Biology, Biophysics Interdepartmental Group and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario, Canada.
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6
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Challenges in drug delivery to the brain: Nature is against us. J Control Release 2012; 164:145-55. [DOI: 10.1016/j.jconrel.2012.04.044] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 04/24/2012] [Accepted: 04/29/2012] [Indexed: 01/12/2023]
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7
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Zeng X, Andrade CAS, Oliveira MDL, Sun XL. Carbohydrate–protein interactions and their biosensing applications. Anal Bioanal Chem 2011; 402:3161-76. [DOI: 10.1007/s00216-011-5594-y] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 11/02/2011] [Accepted: 11/20/2011] [Indexed: 01/16/2023]
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8
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Roy B, Ferdjani S, Tellier C, Rabiller C. Novel and convergent synthesis of modified glycosphingolipids, galactosyl-5-aza-sphinganines, by a diversity-oriented method. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.05.054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Prinetti A, Prioni S, Chiricozzi E, Schuchman EH, Chigorno V, Sonnino S. Secondary Alterations of Sphingolipid Metabolism in Lysosomal Storage Diseases. Neurochem Res 2011; 36:1654-68. [DOI: 10.1007/s11064-010-0380-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2010] [Indexed: 12/20/2022]
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10
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Role of Gangliosides and Plasma Membrane-Associated Sialidase in the Process of Cell Membrane Organization. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 705:297-316. [DOI: 10.1007/978-1-4419-7877-6_14] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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11
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Park JW. Ca2+-induced effect on mechanical properties of sulfatide-incorporated vesicles. J Membr Biol 2010; 238:63-8. [PMID: 21088830 DOI: 10.1007/s00232-010-9319-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 11/03/2010] [Indexed: 11/24/2022]
Abstract
The Ca(2+)-induced effect on the nanomechanical properties of vesicles prepared at a different ratio of dipalmitoylphosphatidylcholine (DPPC)/sulfatide was studied using atomic force microscope (AFM) on a mica surface. Vesicles were prepared by extrusion and adsorbed on the mica surface. The forces, measured between an AFM tip and the vesicle, showed that the breakthrough of the tip into the vesicles occurred two times. Force data prior to the first breakthrough were fitted well with the Hertzian model to estimate Young's modulus and bending modulus of the vesicles. Sulfatide incorporation led to a decrease of around 90% in Young's modulus and bending modulus of the vesicles due to the hydration of the headgroups, while the addition of Ca(2+) induced dehydration to recover the properties. The change of the physical properties seems to be attributed to the headgroup packing order of the vesicles, which is determined by the interference with the hydration shell.
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Affiliation(s)
- Jin-Won Park
- Department of Chemical Engineering, College of Engineering, Seoul National University of Science and Technology, 172 Gongreung 2-dong, Nowon-gu, Seoul, 139-743, South Korea.
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12
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Nuti F, Peroni E, Real-Fernández F, Bonache MA, Le Chevalier-Isaad A, Chelli M, Lubin-Germain N, Uziel J, Rovero P, Lolli F, Papini AM. Posttranslationally modified peptides efficiently mimicking neoantigens: A challenge for theragnostics of autoimmune diseases. Biopolymers 2010; 94:791-9. [DOI: 10.1002/bip.21456] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Sulfatide incorporation effect on mechanical properties of vesicles. Colloids Surf B Biointerfaces 2010; 80:59-62. [DOI: 10.1016/j.colsurfb.2010.05.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 05/17/2010] [Accepted: 05/21/2010] [Indexed: 11/20/2022]
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14
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Piccinini M, Scandroglio F, Prioni S, Buccinnà B, Loberto N, Aureli M, Chigorno V, Lupino E, DeMarco G, Lomartire A, Rinaudo MT, Sonnino S, Prinetti A. Deregulated sphingolipid metabolism and membrane organization in neurodegenerative disorders. Mol Neurobiol 2010; 41:314-40. [PMID: 20127207 DOI: 10.1007/s12035-009-8096-6] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 12/22/2009] [Indexed: 12/13/2022]
Abstract
Sphingolipids are polar membrane lipids present as minor components in eukaryotic cell membranes. Sphingolipids are highly enriched in nervous cells, where they exert important biological functions. They deeply affect the structural and geometrical properties and the lateral order of cellular membranes, modulate the function of several membrane-associated proteins, and give rise to important intra- and extracellular lipid mediators. Sphingolipid metabolism is regulated along the differentiation and development of the nervous system, and the expression of a peculiar spatially and temporarily regulated sphingolipid pattern is essential for the maintenance of the functional integrity of the nervous system: sphingolipids in the nervous system participate to several signaling pathways controlling neuronal survival, migration, and differentiation, responsiveness to trophic factors, synaptic stability and synaptic transmission, and neuron-glia interactions, including the formation and stability of central and peripheral myelin. In several neurodegenerative diseases, sphingolipid metabolism is deeply deregulated, leading to the expression of abnormal sphingolipid patterns and altered membrane organization that participate to several events related to the pathogenesis of these diseases. The most impressive consequence of this deregulation is represented by anomalous sphingolipid-protein interactions that are at least, in part, responsible for the misfolding events that cause the fibrillogenic and amyloidogenic processing of disease-specific protein isoforms, such as amyloid beta peptide in Alzheimer's disease, huntingtin in Huntington's disease, alpha-synuclein in Parkinson's disease, and prions in transmissible encephalopathies. Targeting sphingolipid metabolism represents today an underexploited but realistic opportunity to design novel therapeutic strategies for the intervention in these diseases.
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Affiliation(s)
- Marco Piccinini
- Section of Biochemistry, Department of Medicine and Experimental Oncology, University of Turin, Turin, Italy
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15
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Bauer NG, Richter-Landsberg C, Ffrench-Constant C. Role of the oligodendroglial cytoskeleton in differentiation and myelination. Glia 2010; 57:1691-705. [PMID: 19455583 DOI: 10.1002/glia.20885] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oligodendrocytes, the myelin-forming cells of the central nervous system, are in culture characterized by an elaborate process network, terminating in flat membranous sheets that are rich in myelin-specific proteins and lipids, and spirally wrap axons forming a compact insulating layer in vivo. By analogy with other cell types, maintenance and stability of these processes, as well as the formation of the myelin sheath, likely rely on a pronounced cytoskeleton consisting of microtubules and microfilaments. While the specialized process of wrapping and compaction forming the myelin sheath is not well understood, considerably more is known about how cytoskeletal organization is mediated by extracellular and intracellular signals and other interaction partners during oligodendrocyte differentiation and myelination. Here, we review the current state of knowledge on the role of the oligodendrocyte cytoskeleton in differentiation with an emphasis on signal transduction mechanisms and will attempt to draw out implications for its significance in myelination.
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Affiliation(s)
- Nina G Bauer
- MRC Centre for Regenerative Medicine, Centre for Multiple Sclerosis Research, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom.
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16
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Sonnino S, Prinetti A. Gangliosides as regulators of cell membrane organization and functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 688:165-84. [PMID: 20919654 DOI: 10.1007/978-1-4419-6741-1_12] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Gangliosides, characteristic complex lipids present in the external layer of plasma membranes, deeply influence the organization of the membrane as a whole and the function of specific membrane associated proteins due to lipid-lipid and lipid-protein lateral interaction. Here we discuss the basis for the membrane-organizing potential of gangliosides, examples of ganglioside-regulated membrane protein complexes and the mechanisms for the regulation of ganglioside membrane composition.
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Affiliation(s)
- Sandro Sonnino
- Center of Excellence on Neurodegenerative Diseases, Department of Medical Chemistry, University of Milan, Segrate, Italy
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17
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Jackman N, Ishii A, Bansal R. Oligodendrocyte development and myelin biogenesis: parsing out the roles of glycosphingolipids. Physiology (Bethesda) 2009; 24:290-7. [PMID: 19815855 DOI: 10.1152/physiol.00016.2009] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The myelin sheath is an extension of the oligoddendrocyte (OL) plasma membrane enriched in lipids that ensheaths the axons of the central and peripheral nervous system. Here, we review the involvement of glycosphingolipids in myelin/OL functions, including the regulation of OL differentiation, lipid raft-mediated trafficking and signaling, and neuron-glia interactions.
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Affiliation(s)
- Nicole Jackman
- Department of Neuroscience, University of Connecticut Medical School, Farmington, Connecticut, USA
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18
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Participation of galactosylceramide and sulfatide in glycosynapses between oligodendrocyte or myelin membranes. FEBS Lett 2009; 584:1771-8. [DOI: 10.1016/j.febslet.2009.11.074] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 11/19/2009] [Accepted: 11/20/2009] [Indexed: 01/05/2023]
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19
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Husted C, Dhondup L. Tibetan Medical Interpretation of Myelin Lipids and Multiple Sclerosis. Ann N Y Acad Sci 2009; 1172:278-96. [DOI: 10.1196/annals.1393.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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20
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Harauz G, Ladizhansky V, Boggs JM. Structural Polymorphism and Multifunctionality of Myelin Basic Protein. Biochemistry 2009; 48:8094-104. [DOI: 10.1021/bi901005f] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Joan M. Boggs
- Department of Molecular Structure and Function, Research Institute, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5G 1L5, Canada
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21
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Myelin, DIGs, and membrane rafts in the central nervous system. Prostaglandins Other Lipid Mediat 2009; 91:118-29. [PMID: 19379822 DOI: 10.1016/j.prostaglandins.2009.04.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 04/08/2009] [Accepted: 04/09/2009] [Indexed: 11/21/2022]
Abstract
Over the past 40 years our understanding of the organization of cell membranes has changed dramatically. Membranes are no longer viewed as a homogenous sea of phospholipids studded with randomly positioned islands of proteins. Our current view of the membrane involves the formation of small lipid clusters, comprised mainly of cholesterol and sphingolipids, known as membrane rafts. These lipid clusters apparently include and exclude specific proteins leading to the hypothesis that these domains (1) regulate cellular polarity and compartmentalization through trafficking and sorting, (2) provide platforms for cellular signaling and adhesion, and (3) function as cellular gate keepers. Tremendous controversy surrounds the concept of membrane rafts primarily because these small, highly dynamic entities are too small to be observed with traditional microscopic methods and the most utilized approach for raft analysis relies on poorly quantified, inconsistent biochemical extractions. New analytical approaches are being developed and applied to the study of membrane rafts and these techniques provide great promise for furthering our understanding of these enigmatic domains. In this review we will provide a brief summary of the current understanding of membrane rafts, utilizing the CNS myelin literature for illustrative purposes, and present caveats that should be considered when studying these domains.
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22
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Björkqvist Y, Nybond S, Nyholm T, Slotte J, Ramstedt B. N-palmitoyl-sulfatide participates in lateral domain formation in complex lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:954-62. [DOI: 10.1016/j.bbamem.2007.12.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Revised: 12/11/2007] [Accepted: 12/16/2007] [Indexed: 11/29/2022]
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23
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Regina Todeschini A, Hakomori SI. Functional role of glycosphingolipids and gangliosides in control of cell adhesion, motility, and growth, through glycosynaptic microdomains. BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1780:421-33. [PMID: 17991443 PMCID: PMC2312458 DOI: 10.1016/j.bbagen.2007.10.008] [Citation(s) in RCA: 322] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Revised: 09/29/2007] [Accepted: 10/12/2007] [Indexed: 01/11/2023]
Abstract
At cell surface microdomains, glycosyl epitopes, carried either by glycosphingolipids, N- or O-linked oligosaccharides, are recognized by carbohydrate-binding proteins or complementary carbohydrates. In both cases, the carbohydrate epitopes may be clustered with specific signal transducers, tetraspanins, adhesion receptors or growth factor receptors. Through this framework, carbohydrates can mediate cell signaling leading to changes in cellular phenotype. Microdomains involved in carbohydrate-dependent cell adhesion inducing cell activation, motility, and growth are termed "glycosynapse". In this review a historical synopsis of glycosphingolipids-enriched microdomains study leading to the concept of glycosynapse is presented. Examples of glycosynapse as signaling unit controlling the tumor cell phenotype are discussed in three contexts: (i) Cell-to-cell adhesion mediated by glycosphingolipids-to-glycosphingolipids interaction between interfacing glycosynaptic domains, through head-to-head (trans) carbohydrate-to-carbohydrate interaction. (ii) Functional role of GM3 complexed with tetraspanin CD9, and interaction of such complex with integrins, or with fibroblast growth factor receptor, to control tumor cell phenotype and its reversion to normal cell phenotype. (iii) Inhibition of integrin-dependent Met kinase activity by GM2/tetraspanin CD82 complex in glycosynaptic microdomain. Data present here suggest that the organizational status of glycosynapse strongly affects cellular phenotype influencing tumor cell malignancy.
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Affiliation(s)
- Adriane Regina Todeschini
- Division of Biomembrane Research, Pacific Northwest Research Institute, University of Washington, Seattle, WA, USA.
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Boggs JM, Gao W, Hirahara Y. Myelin glycosphingolipids, galactosylceramide and sulfatide, participate in carbohydrate–carbohydrate interactions between apposed membranes and may form glycosynapses between oligodendrocyte and/or myelin membranes. Biochim Biophys Acta Gen Subj 2008; 1780:445-55. [DOI: 10.1016/j.bbagen.2007.10.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Revised: 10/25/2007] [Accepted: 10/25/2007] [Indexed: 12/12/2022]
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Boggs JM, Gao W, Hirahara Y. Signal transduction pathways involved in interaction of galactosylceramide/sulfatide-containing liposomes with cultured oligodendrocytes and requirement for myelin basic protein and glycosphingolipids. J Neurosci Res 2008; 86:1448-58. [DOI: 10.1002/jnr.21603] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Prinetti A, Chigorno V, Mauri L, Loberto N, Sonnino S. Modulation of cell functions by glycosphingolipid metabolic remodeling in the plasma membrane. J Neurochem 2007; 103 Suppl 1:113-25. [DOI: 10.1111/j.1471-4159.2007.04714.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Huang M, Shen Z, Zhang Y, Zeng X, Wang PG. Alkanethiol containing glycopolymers: A tool for the detection of lectin binding. Bioorg Med Chem Lett 2007; 17:5379-83. [PMID: 17728132 DOI: 10.1016/j.bmcl.2007.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 07/31/2007] [Accepted: 08/01/2007] [Indexed: 10/23/2022]
Abstract
Glycopolymers are useful macromolecules with a non-carbohydrate backbone for presenting saccharides in multivalent form. Here, glycopolymers containing mannose and alkanethiol linker were synthesized through substituting preactivated poly [N-(acryloyloxy) succinimide] (pNAS) with amine-containing monomer. With the obtained glycopolymers, a glycosurface was generated on the gold surface of quartz crystal microbalance (QCM) through self-assembled strategy by the use of alkanethiol functional group. Furthermore, the resulting glycosurface was used to detect the binding of mannose specific lectin concanavalin A (Con A).
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Affiliation(s)
- Mingchuan Huang
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
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Meikle L, Talos DM, Onda H, Pollizzi K, Rotenberg A, Sahin M, Jensen FE, Kwiatkowski DJ. A mouse model of tuberous sclerosis: neuronal loss of Tsc1 causes dysplastic and ectopic neurons, reduced myelination, seizure activity, and limited survival. J Neurosci 2007; 27:5546-58. [PMID: 17522300 PMCID: PMC6672762 DOI: 10.1523/jneurosci.5540-06.2007] [Citation(s) in RCA: 338] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Tuberous sclerosis (TSC) is a hamartoma syndrome caused by mutations in TSC1 or TSC2 in which cerebral cortical tubers and seizures are major clinical issues. We have engineered mice in which most cortical neurons lose Tsc1 expression during embryonic development. These Tsc1 mutant mice display several neurological abnormalities beginning at postnatal day 5 with subsequent failure to thrive and median survival of 35 d. The mice also display clinical and electrographic seizures both spontaneously and with physical stimulation, and some seizures end in a fatal tonic phase. Many cortical and hippocampal neurons are enlarged and/or dysplastic in the Tsc1 mutant mice, strongly express phospho-S6, and are ectopic in multiple sites in the cortex and hippocampus. There is a striking delay in myelination in the mutant mice, which appears to be caused by an inductive neuronal defect. This new TSC brain model replicates several features of human TSC brain lesions and implicates an important function of Tsc1/Tsc2 in neuronal development.
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Affiliation(s)
- Lynsey Meikle
- Division of Translational Medicine, Department of Medicine, Brigham and Women's Hospital and
| | - Delia M. Talos
- Department of Neurology, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Hiroaki Onda
- Division of Translational Medicine, Department of Medicine, Brigham and Women's Hospital and
| | - Kristen Pollizzi
- Division of Translational Medicine, Department of Medicine, Brigham and Women's Hospital and
| | - Alexander Rotenberg
- Department of Neurology, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Mustafa Sahin
- Department of Neurology, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Frances E. Jensen
- Department of Neurology, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - David J. Kwiatkowski
- Division of Translational Medicine, Department of Medicine, Brigham and Women's Hospital and
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DeBruin LS, Haines JD, Bienzle D, Harauz G. Partitioning of myelin basic protein into membrane microdomains in a spontaneously demyelinating mouse model for multiple sclerosisThis paper is one of a selection of papers published in this Special Issue, entitled CSBMCB — Membrane Proteins in Health and Disease. Biochem Cell Biol 2006; 84:993-1005. [PMID: 17215885 DOI: 10.1139/o06-180] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We have characterized the lipid rafts in myelin from a spontaneously demyelinating mouse line (ND4), and from control mice (CD1 background), as a function of age and severity of disease. Myelin was isolated from the brains of CD1 and ND4 mice at various ages, and cold lysed with 1.5% CHAPS (3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulphonate). The lysate was separated by low-speed centrifugation into supernatant and pellet fractions, which were characterized by Western blotting for myelin basic protein (MBP) isoforms and their post-translationally modified variants. We found that, with maturation and with disease progression, there was a specific redistribution of the 14–21.5 kDa MBP isoforms (classic exon-II-containing vs exon-II-lacking) and phosphorylated forms into the supernatant and pellet. Further fractionation of the supernatant to yield detergent-resistant membranes (DRMs), representing coalesced lipid rafts, showed these to be highly enriched in exon-II-lacking MBP isoforms, and deficient in methylated MBP variants, in mice of both genotypes. The DRMs from the ND4 mice appeared to be enriched in MBP phosphorylated by MAP kinase at Thr95 (murine 18.5 kDa numbering). These studies indicate that different splice isoforms and post-translationally modified charge variants of MBP are targeted to different microdomains in the myelin membrane, implying multifunctionality of this protein family in myelin maintenance.
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Affiliation(s)
- Lillian S DeBruin
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
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Debruin LS, Harauz G. White Matter Rafting––Membrane Microdomains in Myelin. Neurochem Res 2006; 32:213-28. [PMID: 17031566 DOI: 10.1007/s11064-006-9137-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2006] [Indexed: 02/08/2023]
Abstract
The myelin membrane comprises a plethora of regions that are compositionally, ultrastructurally, and functionally distinct. Biochemical dissection of oligodendrocytes, Schwann cells, and central and peripheral nervous system myelin by means such as cold-detergent extraction and differential fractionation has led to the identification of a variety of detergent-resistant membrane assemblies, some of which represent putative signalling platforms. We review here the different microdomains that have hitherto been identified in the myelin membrane, particularly lipid rafts, caveolae, and cellular junctions such as the tight junctions that are found in the radial component of the CNS myelin sheath.
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Affiliation(s)
- Lillian S Debruin
- Department of Molecular and Cellular Biology, and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road East, N1G 2W1, Guelph, ON, Canada.
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Rai AN, Basu A. Synthesis of the glycosphingolipid beta-galactosyl ceramide and analogues via olefin cross metathesis. J Org Chem 2006; 70:8228-30. [PMID: 16277356 DOI: 10.1021/jo051069y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The preparation of the glycosphingolipid galactosyl ceramide from an orthogonally protected five-carbon building block is described. The main chain of the lipid is installed via a highly stereoselective olefin cross metathesis reaction. The methodology permits the facile preparation of glycolipids which vary in the length of the main carbon chain.
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Affiliation(s)
- Anand Narain Rai
- Department of Chemistry, Brown University, Box H, Providence, Rhode Island 02912, USA
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Hill CMD, Libich DS, Harauz G. Assembly of tubulin by classic myelin basic protein isoforms and regulation by post-translational modification. Biochemistry 2006; 44:16672-83. [PMID: 16342957 DOI: 10.1021/bi050646+] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Myelin basic protein (MBP), a highly cationic protein that maintains the structure of the myelin sheath, associates with tubulin in vivo. The in vitro assembly of tubulin by MBP was examined here using several assays. The unmodified C1 component of 18.5 kDa bovine MBP (bC1) assembled tubulin into microtubules in a dose-dependent manner via filamentous intermediates, and was able simultaneously to promote the formation of microtubule bundles. The critical tubulin concentration in the presence of bC1 was 0.69 +/- 0.05 microM. The effects of post-translational modifications (such as deamidation and phosphorylation) were assayed by comparing the bC1-bC6 components of 18.5 kDa bovine MBP; an increasing level of modification enhanced the ability of MBP to assemble tubulin. The effects of charge reduction via deimination were examined using recombinant murine isoforms emulating the unmodified C1 and deiminated C8 isoforms of 18.5 kDa MBP; both rmC1 and rmC8 exhibited a comparable ability to assemble tubulin. The effects of alternate exon recombination of the classic MBP variants were tested using the recombinant murine 21.5, 17.22, and 14 kDa isoforms. The isoforms containing regions derived from exon II of the classic MBP gene, 21.5 and 17.22 kDa MBP, showed no substantial difference in the extent of tubulin polymerization and bundling when compared to those of 18.5 kDa MBP. The 14 kDa isoform and two terminal deletion mutants of rmC1 were able to induce microtubule polymerization, but not bundling, to the same degree as the longer proteins. Finally, bC1 was shown to disrupt and aggregate planar sheets of crystalline tubulin stabilized by paclitaxel, establishing that these structures are not suitable substrates for the formation of MBP cocrystals.
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Affiliation(s)
- Christopher M D Hill
- Department of Molecular and Cellular Biology and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road East, Guelph, Ontario, Canada N1G 2W1
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Zhang Y, Luo S, Tang Y, Yu L, Hou KY, Cheng JP, Zeng X, Wang PG. Carbohydrate−Protein Interactions by “Clicked” Carbohydrate Self-Assembled Monolayers. Anal Chem 2006; 78:2001-8. [PMID: 16536439 DOI: 10.1021/ac051919+] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A Huisgen 1,3-dipolar cycloaddition "click chemistry" was employed to immobilize azido sugars (mannose, lactose, alpha-Gal) to fabricate carbohydrate self-assembled monolayers (SAMs) on gold. This fabrication was based on preformed SAM templates incorporated with alkyne terminal groups, which could further anchor the azido sugars to form well-packed, stable, and rigid sugar SAMs. The clicked mannose, lactose, and alpha-Gal trisaccharide SAMs were used in the analysis of specific carbohydrate-protein interactions (i.e., mannose-Con A; ECL-lactose, alpha-Gal-anti-Gal). The apparent affinity constant of Con A binding to mannose was (8.7 +/- 2.8) x 10(5) and (3.9 +/- 0.2) x 10(6) M(-1) measured by QCM and SPR, respectively. The apparent affinity constants of lactose binding with ECL and alpha-Gal binding with polyclonal anti-Gal antibody were determined to be (4.6 +/- 2.4) x 10(6) and (6.7 +/- 3.3) x 10(6) M(-1), respectively by QCM. SPR, QCM, AFM, and electrochemistry studies confirmed that the carbohydrate SAM sensors maintained the specificity to their corresponding lectins and nonspecific adsorption on the clicked carbohydrate surface was negligible. This study showed that the clicked carbohydrate SAMs in concert with nonlabel QCM or SPR offered a potent platform for high-throughput characterization of carbohydrate-protein interactions. Such a combination should complement other methods such as ITC and ELISA in a favorable manner and provide insightful knowledge for the corresponding complex glycobiological processes.
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Affiliation(s)
- Yun Zhang
- Department of Biochemistry and Chemistry, The Ohio State University, Columbus, Ohio 43210, USA
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Carvalho de Souza A, Kamerling JP. Analysis of carbohydrate-carbohydrate interactions using gold glyconanoparticles and oligosaccharide self-assembling monolayers. Methods Enzymol 2006; 417:221-43. [PMID: 17132508 DOI: 10.1016/s0076-6879(06)17016-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbohydrates are the most extended structures exposed at the surface of most cells. These carbohydrate chains, when arranged in polyvalent clusters, offer a rich supply of low-affinity binding sites, making them a reliable and flexible system to regulate cell adhesion and recognition. The very first model system for cell-cell recognition by means of carbohydrate-carbohydrate interactions in the animal kingdom came from a primitive invertebrate animal: the marine sponge. During the past 50 years, studies have shown that highly repetitive carbohydrate motives on extracellular proteoglycan supramolecular complexes of marine sponge cells are involved in the species-specific adhesion. In this chapter, some glyconanotechnology procedures are described for the detailed investigation of the role of a carbohydrate epitope in the marine sponge cell recognition. The various protocols are generally applicable in other areas of glycoscience.
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Zaraiskaya T, Jeffrey KR. Molecular dynamics simulations and 2H NMR study of the GalCer/DPPG lipid bilayer. Biophys J 2005; 88:4017-31. [PMID: 15764671 PMCID: PMC1305633 DOI: 10.1529/biophysj.104.054601] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2004] [Accepted: 02/28/2005] [Indexed: 01/25/2023] Open
Abstract
Molecular dynamics simulations were performed on a two-component lipid bilayer system in the liquid crystalline phase at constant pressure and constant temperature. The lipid bilayers were composed of a mixture of neutral galactosylceramide (GalCer) and charged dipalmitoylphosphatidylglycerol (DPPG) lipid molecules. Two lipid bilayer systems were prepared with GalCer:DPPG ratio 9:1 (10%-DPPG system) and 3:1 (25%-DPPG system). The 10%-DPPG system represents a collapsed state lipid bilayer, with a narrow water space between the bilayers, and the 25%-DPPG system represents an expanded state with a fluid space of approximately 10 nm. The number of lipid molecules used in each simulation was 1024, and the length of the production run simulation was 10 ns. The simulations were validated by comparing the results with experimental data for several important aspects of the bilayer structure and dynamics. Deuterium order parameters obtained from (2)H NMR experiments for DPPG chains are in a very good agreement with those obtained from molecular dynamics simulations. The surface area per GalCer lipid molecule was estimated to be 0.608 +/- 0.011 nm(2). From the simulated electron density profiles, the bilayer thickness defined as the distance between the phosphorus peaks across the bilayer was calculated to be 4.21 nm. Both simulation systems revealed a tendency for cooperative bilayer undulations, as expected in the liquid crystalline phase. The interaction of water with the GalCer and DPPG oxygen atoms results in a strong water ordering in a spherical hydration shell and the formation of hydrogen bonds (H-bonds). Each GalCer lipid molecule makes 8.6 +/- 0.1 H-bonds with the surrounding water, whereas each DPPG lipid molecule makes 8.3 +/- 0.1 H-bonds. The number of water molecules per GalCer or DPPG in the hydration shell was estimated to be 10-11 from an analysis of the radial distribution functions. The formation of the intermolecular hydrogen bonds was observed between hydroxyl groups from the opposing GalCer sugar headgroups, giving an energy of adhesion in the range between -1.0 and -3.4 erg/cm(2). We suggest that this value is the contribution of the hydrogen-bond component to the net adhesion energy between GalCer bilayers in the liquid crystalline phase.
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Affiliation(s)
- T Zaraiskaya
- Department of Physics, University of Guelph, Ontario, Canada
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