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Margiotta A. Role of SNAREs and Rabs in Myelin Regulation. Int J Mol Sci 2023; 24:ijms24119772. [PMID: 37298723 DOI: 10.3390/ijms24119772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/31/2023] [Accepted: 06/03/2023] [Indexed: 06/12/2023] Open
Abstract
The myelin sheath is an insulating layer around the nerves of the brain and spinal cord which allows a fast and efficient nerve conduction. Myelin is made of protein and fatty substances and gives protection for the propagation of the electrical impulse. The myelin sheath is formed by oligodendrocytes in the central nervous system (CNS) and by Schwann cells in the peripheral nervous system (PNS). The myelin sheath presents a highly organized structure and expands both radially and longitudinally, but in a different way and with a different composition. Myelin alterations determine the onset of several neuropathies, as the electrical signal can be slowed or stopped. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and ras (rat sarcoma)-associated binding proteins (rabs) have been proved to contribute to several aspects regarding the formation of myelin or dysmyelination. Here, I will describe the role of these proteins in regulating membrane trafficking and nerve conduction, myelin biogenesis and maintenance.
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Affiliation(s)
- Azzurra Margiotta
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, 5009 Bergen, Norway
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2
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García-Álvarez I, Fernández-Mayoralas A, Moreno-Lillo S, Sánchez-Sierra M, Nieto-Sampedro M, Doncel-Pérez E. Inhibition of glial proliferation, promotion of axonal growth and myelin production by synthetic glycolipid: A new approach for spinal cord injury treatment. Restor Neurol Neurosci 2016; 33:895-910. [PMID: 26484699 DOI: 10.3233/rnn-150572] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE After spinal cord injury (SCI) a glial scar is generated in the area affected that forms a barrier for axon growth and myelination, preventing functional recovery. Recently, we have described a synthetic glycolipid (IG20) that inhibited proliferation of human glioma cells. We show now that IG20 inhibited the proliferation of astrocytes and microglial cells, the principal cellular components of the glial scar, and promoting axonal outgrowth and myelin production in vitro. METHODS Glial cells were inhibited with IG20 (IC50≈10 μM) and studied by RT-PCR, Western Blotting, immunoprecipitation and fluorescence microscopy. Axonal outgrowth in dorsal root ganglia (DRG) and myelin production by oligodendrocytes were analyzed by immunocytochemistry. Adult rats were assayed in spinal cord contusion model and the recovery of treated animals (n = 6) and controls (n = 6) was followed. RESULTS The IG20 was localized in the cytosol of glial cells, forming a complex with RhoGDIα, a regulator of RhoGTPases. Treatment of astroglial cultures with IG20 increase the expression of BDNF receptor genes (TrkBT1, TrkB Full). IG20 reduced the astroglial marker GFAP, while increasing production of myelin basic protein in oligodendrocytes and promoted axonal outgrowth from DRG neurons. Local injection of IG20, near a spinal cord contusion, promoted the recovery of lesioned animals analyzed by BBB test (P < 0.05). CONCLUSIONS We propose that inhibition of astrocytes and microglia by IG20 could be diminished the glial scar formation, inducing the re-growth and myelination of axons, these elements constitute a new approach for SCI therapy.
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Affiliation(s)
- Isabel García-Álvarez
- Grupo de Química Neuro-regenerativa, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla La Mancha (SESCAM), Finca La Peraleda s/n, Toledo, Spain
| | | | - Sandra Moreno-Lillo
- Grupo de Química Neuro-regenerativa, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla La Mancha (SESCAM), Finca La Peraleda s/n, Toledo, Spain
| | - María Sánchez-Sierra
- Grupo de Química Neuro-regenerativa, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla La Mancha (SESCAM), Finca La Peraleda s/n, Toledo, Spain
| | | | - Ernesto Doncel-Pérez
- Grupo de Química Neuro-regenerativa, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla La Mancha (SESCAM), Finca La Peraleda s/n, Toledo, Spain
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3
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Rodriguez-Gabin AG, Ortiz E, Demoliner K, Si Q, Almazan G, Larocca JN. Interaction of Rab31 and OCRL-1 in oligodendrocytes: its role in transport of mannose 6-phosphate receptors. J Neurosci Res 2010; 88:589-604. [PMID: 19795375 DOI: 10.1002/jnr.22236] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Rab31, a protein that we cloned from an oligodendrocyte cDNA library, is required for transport of mannose 6-phosphate receptors (MPRs) from the trans-Golgi network (TGN) to endosomes and for Golgi/TGN organization. Here we extend the knowledge of the mechanism of action of Rab31 by demonstrating its interaction with OCRL-1, a phosphatidylinositol 4,5-diphosphate 5-phosphatase (PI(4,5)P(2) 5-phosphatase) that regulates the levels of PI(4,5)P(2) and PI(4)P, molecules involved in transport and Golgi/TGN organization. We show that Rab31 interacts with OCRL-1 in a yeast two-hybrid system, GST-Rab31 pull-down experiments, and coimmunoprecipitation of OCRL-1 using oligodendrocyte culture lysates. Rab31 and OCRL-1 colocalize in the TGN, post-TGN carriers, and endosomes. Cation-dependent MPR (CD-MPR) is sorted to OCRL-1-containing carriers, but CD63 and vesicular stomatitis virus G (VSVG) are not. siRNA-mediated depletion of endogenous Rab31 causes collapse of the TGN apparatus and markedly decreases the levels of OCRL-1 in the TGN and endosomes. Our observations indicate that the role of Rab31 in the Golgi/TGN structure and transport of MPRs depends on its capability to recruit OCRL-1 to domains of the TGN where the formation of carriers occurs. The importance of our observations is highlighted by the fact that mutation of OCRL-1 causes demyelination in humans.
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Affiliation(s)
- A G Rodriguez-Gabin
- Department of Neurology, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
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4
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Ng EL, Ng JJ, Liang F, Tang BL. Rab22B is expressed in the CNS astroglia lineage and plays a role in epidermal growth factor receptor trafficking in A431 cells. J Cell Physiol 2009; 221:716-28. [DOI: 10.1002/jcp.21911] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Maier O, De Jonge J, Nomden A, Hoekstra D, Baron W. Lovastatin induces the formation of abnormal myelin-like membrane sheets in primary oligodendrocytes. Glia 2009; 57:402-13. [PMID: 18814266 DOI: 10.1002/glia.20769] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Statins, well-known inhibitors of cholesterol synthesis and protein isoprenylation, have been proposed as therapeutic drugs for multiple sclerosis (MS). As lovastatin and simvastatin, which are currently tested for their use in MS, can cross the blood-brain barrier, they may affect cellular processes in the central nervous system. This is especially relevant with respect to remyelination as a proposed additional treatment for MS, because cholesterol is a major component of myelin. Here, we show that primary oligodendrocytes, treated with lovastatin, form extensive membrane sheets, which contain galactosphingolipids. However, these membrane sheets are devoid of the major myelin proteins, myelin basic protein (MBP) and proteolipid protein (PLP). Reduced MBP protein expression was confirmed by SDS-PAGE and Western blotting, and in situ hybridization experiments revealed that lovastatin blocks MBP mRNA transport into oligodendrocyte processes. In contrast, PLP expression was only mildly affected by lovastatin. However, lovastatin treatment resulted in intracellular accumulation of PLP and prevented its translocation to the cell surface. Interestingly, another inhibitor of cholesterol synthesis (ro48-8071), which does not interfere with isoprenylation, had a similar effect on the localization of PLP, but it did not affect MBP expression and localization. These results suggest that lovastatin affects PLP transport predominantly by the inhibition of cholesterol synthesis, whereas reduced MBP expression is caused by impaired isoprenylation. Based on these results we recommend to carefully monitor the effect of statins on myelination prior to their use in demyelinating diseases.
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Affiliation(s)
- Olaf Maier
- Section of Membrane Cell Biology, Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
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6
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Chia WJ, Tang BL. Emerging roles for Rab family GTPases in human cancer. Biochim Biophys Acta Rev Cancer 2009; 1795:110-6. [PMID: 19425190 DOI: 10.1016/j.bbcan.2008.10.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Member of the Ras-associated binding (Rab) family of small GTPases function as molecular switches regulating vesicular transport in eukaryotes cells. Their pathophysiological roles in human malignancies are less well-known compared to members of Ras and Rho families. Several members of the Rab family have, however, been shown to be aberrantly expressed in various cancer tissues. Recent findings have also revealed , in particular, Rab25 as a determinant of tumor progression and aggressiveness of epithelial cancers. Rab25 associates with alpha5beta1 integrin, and enhances tumor cell invasion by directing the localization of integrin-containing vesicles to the leading edge of matrix invading pseudopodia. We summarized here recent integrin on Rab25 and other Rabs implicated to be involved in a variety of human cancers, and discussed plausible mechanisms of how dysregulation of Rab expression could be tumorigenic or tumor suppressive.
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Affiliation(s)
- Wan Jie Chia
- Department of Biochemistry,Yong Loo Lin School of Medicine, national University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
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7
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Anitei M, Cowan AE, Pfeiffer SE, Bansal R. Role for Rab3a in oligodendrocyte morphological differentiation. J Neurosci Res 2009; 87:342-52. [PMID: 18798275 DOI: 10.1002/jnr.21870] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rab3a, a small GTPase important for exocytosis, is uniquely up-regulated as oligodendrocytes enter terminal differentiation and initiate myelin biosynthesis. In this study, we analyze the role of this protein in oligodendrocyte morphological differentiation by using Rab3a overexpression and siRNAi-mediated Rab3a silencing. We found that Rab3a silencing delayed mature oligodendrocyte morphological differentiation but did not interfere with lineage progression of OL progenitors; this is consistent with the high levels of Rab3a expressed by mature oligodendrocytes compared with progenitor cells. Overexpression of GTP-bound, but not that of wild-type, Rab3a delayed OL morphological differentiation; this suggests that expression of a GTP-bound Rab3a mutant interferes with the normal function of endogenous Rab3a. We have also identified in oligodendrocytes two other exocytic small GTPases, Rab27B and RalA. Together, these findings indicate that Rab3a specifically stimulates morphological differentiation of mature oligodendrocytes and thus may be part of the necessary machinery for myelin membrane biogenesis.
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Affiliation(s)
- Mihaela Anitei
- Department of Neuroscience, University of Connecticut Medical School, Farmington, Connecticut 06030-3401, USA
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8
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Ng EL, Tang BL. Rab GTPases and their roles in brain neurons and glia. ACTA ACUST UNITED AC 2008; 58:236-46. [PMID: 18485483 DOI: 10.1016/j.brainresrev.2008.04.006] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Revised: 02/29/2008] [Accepted: 04/06/2008] [Indexed: 12/19/2022]
Affiliation(s)
- Ee Ling Ng
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
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Maier O, Hoekstra D, Baron W. Polarity Development in Oligodendrocytes: Sorting and Trafficking of Myelin Components. J Mol Neurosci 2008; 35:35-53. [DOI: 10.1007/s12031-007-9024-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2007] [Accepted: 11/13/2007] [Indexed: 12/15/2022]
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Anitei M, Ifrim M, Ewart MA, Cowan AE, Carson JH, Bansal R, Pfeiffer SE. A role for Sec8 in oligodendrocyte morphological differentiation. J Cell Sci 2006; 119:807-18. [PMID: 16478790 DOI: 10.1242/jcs.02785] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
In the central nervous system, oligodendrocytes synthesize vast amounts of myelin, a multilamellar membrane wrapped around axons that dramatically enhances nerve transmission. A complex apparatus appears to coordinate trafficking of proteins and lipids during myelin synthesis, but the molecular interactions involved are not well understood. We demonstrate that oligodendrocytes express several key molecules necessary for the targeting of transport vesicles to areas of rapid membrane growth, including the exocyst components Sec8 and Sec6 and the multidomain scaffolding proteins CASK and Mint1. Sec8 overexpression significantly promotes oligodendrocyte morphological differentiation and myelin-like membrane formation in vitro; conversely, siRNA-mediated interference with Sec8 expression inhibits this process, and anti-Sec8 antibody induces a reduction in oligodendrocyte areas. In addition, Sec8 colocalizes, coimmunoprecipitates and cofractionates with the major myelin protein OSP/Claudin11 and with CASK in oligodendrocytes. These results suggest that Sec8 plays a central role in oligodendrocyte membrane formation by regulating the recruitment of vesicles that transport myelin proteins such as OSP/Claudin11 to sites of membrane growth.
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Affiliation(s)
- Mihaela Anitei
- Program of Molecular Biology and Biochemistry, University of Connecticut Medical School, Farmington, CT 06030, USA
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Rodriguez-Gabin AG, Almazan G, Larocca JN. Vesicle transport in oligodendrocytes: probable role of Rab40c protein. J Neurosci Res 2004; 76:758-70. [PMID: 15160388 DOI: 10.1002/jnr.20121] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Intracellular membrane trafficking plays an essential role in the structural and functional organization of oligodendrocytes, which synthesize a large amount of membrane to form myelin. Rab proteins are key components in intracellular vesicular transport. We cloned a novel Rab protein from an oligodendrocyte cDNA library, designating it Rab40c because of its homology with Rab40a and Rab40b. The DNA sequence of Rab40c shows an 843-base pair open reading frame. The deduced amino acid sequence is a protein with 281 amino acids, with a molecular weight of 31,466 Da and an isoelectric point of 9.83. Rab40c presents a number of distinct structural features including a carboxyl terminal extension and amino acid substitutions in the consensus sequence of the GTP-binding motifs. The carboxyl terminal region contains motifs that permit isoprenylation and palmitoylation. Binding studies indicate that Rab40c binds guanosine 5'-0-(3-thiotriphosphate) (GTP gamma S) with a K(d) of 21 microM and has a higher affinity for guanosine triphosphate (GTP) than for guanosine diphosphate (GDP). Rab40c is localized in the perinuclear recycling compartment, suggesting its involvement in endocytic events such as receptor recycling. The importance of this recycling in myelin formation is suggested by the increase in both Rab40c mRNA and Rab40c protein as oligodendrocytes differentiate.
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Affiliation(s)
- A G Rodriguez-Gabin
- Department of Neurology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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12
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Abstract
Intracellular trafficking of membranes plays an essential role in the biogenesis and maintenance of myelin. The requisite proteins and lipids are transported from their sites of synthesis to myelin via vesicles. Vesicle transport is tightly coordinated with synthesis of lipids and proteins. To maintain the structural and functional organization of oligodendrocytes it is essential synchronize the various pathways of vesicle transport and to coordinate vesicle transport with reorganization of cytoskeleton. The systems that regulate the targeting of protein to myelin by vesicle transport are now being described. Here we review the current knowledge of these systems including those involved in (a) protein folding, (b) protein sorting and formation of carrier vesicles, (c) vesicle transport along elements of the cytoskeleton, and (d) vesicle targeting/fusion.
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Affiliation(s)
- J N Larocca
- Department of Neurology/Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
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13
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Rodriguez-Gabin AG, Cammer M, Almazan G, Charron M, Larocca JN. Role of rRAB22b, an oligodendrocyte protein, in regulation of transport of vesicles from trans Golgi to endocytic compartments. J Neurosci Res 2001; 66:1149-60. [PMID: 11746448 DOI: 10.1002/jnr.1253] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Intracellular membrane trafficking plays an essential role in the biogenesis and maintenance of myelin. Members of the Rab protein family are important components of the systems that regulate intracellular vesicle transport. We examine the function of rRab22b, a novel rat Rab protein cloned from an oligodendrocyte cDNA library, by visualizing and identifying in living Hela cells the organelles that contain rRab22b. Our results show that rRab22b is present in the trans Golgi/TGN and endocytic compartments. Trafficking of membranes from trans Golgi to endocytic compartments takes place via small tubulo vesicular organelles containing rRab22b. The formation of vesicles in the trans Golgi also appears to be regulated by rRab22b. Additionally, our results suggest that rRab22b controls the transport of vesicles from the trans Golgi to endocytic compartments that localize in oligodendrocyte processes. That rRab22b is involved in the transport of certain proteins from trans Golgi to myelin is suggested by the evidence that certain proteins being targeted to the plasma membrane are first transported from trans Golgi to endocytic compartments.
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Affiliation(s)
- A G Rodriguez-Gabin
- Department of Neurology/Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA
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Abstract
In the central nervous system (CNS), the myelin sheath is synthesised by oligodendrocytes as a specialised subdomain of an extended plasma membrane, reminiscent of the segregated membrane domains of polarised cells. Myelination takes place within a relatively short period of time and oligodendrocytes must have adapted membrane sorting and transport mechanisms to achieve such a high rate of myelin synthesis and to maintain the unique organisation of the myelin membrane. In adult life, maintenance of the functional myelin sheath requires a carefully orchestrated balance of myelin synthesis and turnover. Imbalance in these processes may cause dys- or demyelination and disease. This review summarises what is currently known about myelin protein trafficking and mistrafficking in oligodendrocytes. We also present data demonstrating distinct transport pathways for myelin structural proteins and the expression of SNARE proteins in differentiating oligodendrocytes. Myelinating glial cells may well serve as a model system for studying general aspects of membrane trafficking and organisation of membrane domains.
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Affiliation(s)
- E M Krämer
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Hermann-Rein-Str. 3, 37035 Göttingen, Germany.
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Harauz G, Ishiyama N, Bates IR. Analogous structural motifs in myelin basic protein and in MARCKS. Mol Cell Biochem 2000; 209:155-63. [PMID: 10942213 DOI: 10.1023/a:1007176216360] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Myelin basic protein (MBP) and myristoylated alanine-rich C-kinase substrate (MARCKS) are similar in terms of having extended conformations regulated by their environment (i.e., solubilised or lipid-associated), N-terminal modifications, a dual nature of interactions with lipids, binding to actin and Ca2+-calmodulin, and being substrates for different kinds of protein kinases. The further sequence similarities of segments of MBP with lipid effector regions of MARCKS, and numerous reports in the literature, support the thesis that some developmental isoform of MBP functions in signal transduction.
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Affiliation(s)
- G Harauz
- Department of Molecular Biology and Genetics, and Biophysics Interdepartmental Group, University of Guelph, Ontario, Canada
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Bouverat BP, Krueger WH, Coetzee T, Bansal R, Pfeiffer SE. Expression of rab GTP-binding proteins during oligodendrocyte differentiation in culture. J Neurosci Res 2000; 59:446-53. [PMID: 10679782 DOI: 10.1002/(sici)1097-4547(20000201)59:3<446::aid-jnr20>3.0.co;2-l] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Oligodendrocytes (OLs) synthesize and transport vast amounts of proteins and lipids from the cell body to the morphologically and biochemically distinct domains of the myelin membrane. From our prediction that regulators of vesicular transport should be up-regulated at the time of myelin production, we hypothesized that the up-regulated and unidentified small GTPases found by Huber et al. [1994a] may be Rab proteins. We have analyzed the mRNA expression of rabs in OLs, and have detected rabs 10, 11b, 18, 24, 26, and 28 in addition to rabs that were found previously. Our data show that among the Rabs so far detected during differentiation, only Rabs 5a and 8a exhibited up-regulation in addition to the previously published Rab3a (Madison et al. [1999], J. Neurochem. 72:988-998). We discuss the limited extent of up-regulation of rabs in the context of the presumed necessity for an increase in Rab activity during myelin assembly.
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Affiliation(s)
- B P Bouverat
- University of Connecticut Health Center, Department of Microbiology and Program in Neurological Sciences, Farmington, Connecticut 06030-3205, USA
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Abstract
Astrocytes release glutamate and aspartate in response to elevated intracellular calcium levels, and it has been proposed that this occurs by a vesicular release mechanism, in which SNARE proteins are implicated. Although syntaxin, synaptobrevin, and cellubrevin have been shown to be expressed by cultured astrocytes, SNAP-25 has not been detected. By using immunocytochemical, immunoblotting, and polymerase chain reaction techniques, the present study demonstrates that SNAP-23, an analogue of SNAP-25, is expressed by astrocytes both in culture and in rat cerebellum. These findings provide additional evidence that astrocytes release excitatory amino acids by a vesicular mechanism involving SNARE proteins. SNAP-23 and also syntaxin 1 and cellubrevin were found to be expressed in glial precursor cells, oligodendrocytes, and microglia. These data suggest that the t-SNAREs SNAP-23 and syntaxin 1 and the v-SNARE cellubrevin participate in general membrane insertion mechanisms involved in diverse glial cell functions such as secretion, phagocytosis, and myelinogenesis.
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Affiliation(s)
- R Hepp
- INSERM Unité 338, Biologie de la Communication Cellulaire, Strasbourg, France.
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