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Burgoyne RD, Barclay JW, Ciufo LF, Graham ME, Handley MTW, Morgan A. The functions of Munc18-1 in regulated exocytosis. Ann N Y Acad Sci 2009; 1152:76-86. [PMID: 19161378 DOI: 10.1111/j.1749-6632.2008.03987.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The activation of regulated exocytosis occurs by a rise in cytosolic Ca(2+) concentration. Synaptotagmins act as the Ca(2+) sensors, whereas the machinery that allows fusion of secretory vesicles with the plasma membrane consists of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins, including syntaxin 1, SNAP-25, and VAMP. Within the pathway leading to exocytosis, there is an essential requirement for a member of the conserved Sec1/Munc18 (SM) protein family, which in neurotransmitter and neurohormone release in mammalian cells is Munc18-1. The exact role of Munc18-1 and the steps within exocytosis in which it acts have been intensively investigated. Current evidence suggests that Munc18-1 acts via distinct modes of interactions with syntaxin 1 and the other SNARE proteins and influences all of the steps leading to exocytosis, including vesicle recruitment, tethering, docking, priming, and membrane fusion.
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Affiliation(s)
- Robert D Burgoyne
- The Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool, United Kingdom.
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52
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Abstract
Toxins that alter neurotransmitter release from nerve terminals are of considerable scientific and clinical importance. Many advances were recently made in the understanding of their molecular mechanisms of action and use in human therapy. Here, we focus on presynaptic neurotoxins, which are very potent inhibitors of the neurotransmitter release because they are endowed with specific enzymatic activities: (1) clostridial neurotoxins with a metallo-proteolytic activity and (2) snake presynaptic neurotoxins with a phospholipase A2 activity.
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Affiliation(s)
- Ornella Rossetto
- Departimento de Scienze Biomediche and Istituto CNR di Neuroscienze, Universita di Padova, Viale G. Colombo 3, 35121, Padova, Italy
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53
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Toonen RF, Verhage M. Munc18-1 in secretion: lonely Munc joins SNARE team and takes control. Trends Neurosci 2007; 30:564-72. [DOI: 10.1016/j.tins.2007.08.008] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Revised: 07/31/2007] [Accepted: 08/14/2007] [Indexed: 01/11/2023]
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54
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Liu S, Wilson KA, Rice-Stitt T, Neiman AM, McNew JA. In vitro fusion catalyzed by the sporulation-specific t-SNARE light-chain Spo20p is stimulated by phosphatidic acid. Traffic 2007; 8:1630-43. [PMID: 17714435 DOI: 10.1111/j.1600-0854.2007.00628.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Sec9p and Spo20p are two SNAP25 family SNARE proteins specialized for different developmental stages in yeast. Sec9p interacts with Sso1/2p and Snc1/2p to mediate intracellular trafficking between post-Golgi vesicles and the plasma membrane during vegetative growth. Spo20p replaces Sec9p in the generation of prospore membranes during sporulation. The function of Spo20p requires enzymatically active Spo14p, which is a phosphatidylcholine (PC)-specific phospholipase D that hydrolyzes PC to generate phosphatidic acid (PA). Phosphatidic acid is required to localize Spo20p properly during sporulation; however, it seems to have additional roles that are not fully understood. Here we compared the fusion mediated by all combinations of the Sec9p or Spo20p C-terminal domains with Sso1p/Sso2p and Snc1p/Snc2p. Our results show that Spo20p forms a less efficient SNARE complex than Sec9p. The combination of Sso2p/Spo20c is the least fusogenic t-SNARE complex. Incorporation of PA in the lipid bilayer stimulates SNARE-mediated membrane fusion by all t-SNARE complexes, likely by decreasing the energetic barrier during membrane merger. This effect may allow the weak SNARE complex containing Spo20p to function during sporulation. In addition, PA can directly interact with the juxtamembrane region of Sso1p, which contributes to the stimulatory effects of PA on membrane fusion. Our results suggest that the fusion strength of SNAREs, the composition of organelle lipids and lipid-SNARE interactions may be coordinately regulated to control the rate and specificity of membrane fusion.
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Affiliation(s)
- Song Liu
- Department of Biochemistry and Cell Biology, Rice University, 6100 Main Street MS-140, Houston, TX 77251-1892, USA
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55
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Abstract
Vesicle fusion is a ubiquitous biological process involved in general membrane trafficking and a variety of specialized events, for example release of neurotransmitters and hormones, sperm acrosome exocytosis, plasma membrane repair and neurite outgrowth. Many vesicle fusion events have long been known to be activated by phospholipases and products of their activity, such as polyunsaturated arachidonic acid. Polyunsaturated fatty acids (PUFAs) have been proposed to have a number of multiple effectors, including ion channels and the cytoskeleton, but the precise mechanism of PUFA action is still unclear. It was recently reported that omega-3 and omega-6 PUFAs can act on syntaxin, a plasma membrane protein directly involved in vesicle fusion. In this review, we will discuss the role of this new mode of PUFA action in exocytosis.
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Affiliation(s)
- Frédéric Darios
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge, UK
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56
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Yakovleva OV, Sitdikova GF, Gerasimova EV, Zefirov AL. Fatty acids modulate transmitter release and functioning of potassium channels in motor nerve endings. NEUROCHEM J+ 2007. [DOI: 10.1134/s1819712407020067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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57
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Das UN. Is metabolic syndrome X a disorder of the brain with the initiation of low-grade systemic inflammatory events during the perinatal period? J Nutr Biochem 2007; 18:701-13. [PMID: 17475465 DOI: 10.1016/j.jnutbio.2007.01.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 12/28/2006] [Accepted: 01/23/2007] [Indexed: 11/19/2022]
Abstract
An imbalance between pro- and anti-inflammatory molecules occurs in metabolic syndrome X. High-energy diet, saturated fats and trans-fats during perinatal period could suppress Delta(6) and Delta(5) desaturases both in the maternal and fetal tissues, resulting in a decrease in the concentrations of long-chain polyunsaturated fatty acids (LCPUFAs): arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) that have a negative feedback control on inflammation. EPA, DHA and AA augment endothelial nitric oxide synthesis, potentiate insulin action both in the peripheral tissues and brain and alter leptin production. LCPUFAs are essential for brain growth and development and synaptogenesis and modulate the action of several neurotransmitters and hypothalamic peptides. This suggests that metabolic syndrome X could be a disorder of the brain due to suboptimal LCPUFAs during perinatal period that triggers low-grade systemic inflammation, implying that perinatal strategies are needed to prevent its development.
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Affiliation(s)
- Undurti N Das
- Department of Molecular and Clinical Medicine, Care Hospital, The Institute of Medical Sciences, Banjara Hills, Hyderabad-500 034, India; UND Life Sciences, Shaker Heights, OH 44120, USA
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58
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Connell E, Darios F, Broersen K, Gatsby N, Peak-Chew SY, Rickman C, Davletov B. Mechanism of arachidonic acid action on syntaxin-Munc18. EMBO Rep 2007; 8:414-9. [PMID: 17363971 PMCID: PMC1852766 DOI: 10.1038/sj.embor.7400935] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 01/23/2007] [Accepted: 01/29/2007] [Indexed: 12/19/2022] Open
Abstract
Syntaxin and Munc18 are, in tandem, essential for exocytosis in all eukaryotes. Recently, it was shown that Munc18 inhibition of neuronal syntaxin 1 can be overcome by arachidonic acid, indicating that this common second messenger acts to disrupt the syntaxin-Munc18 interaction. Here, we show that arachidonic acid can stimulate syntaxin 1 alone, indicating that it is syntaxin 1 that undergoes a structural change in the syntaxin 1-Munc18 complex. Arachidonic acid is incapable of dissociating Munc18 from syntaxin 1 and, crucially, Munc18 remains associated with syntaxin 1 after arachidonic-acid-induced syntaxin 1 binding to synaptosomal-associated protein 25 kDa (SNAP25). We also show that the same principle operates in the case of the ubiquitous syntaxin 3 isoform, highlighting the conserved nature of the mechanism of arachidonic acid action. Neuronal soluble N-ethyl maleimide sensitive factor attachment protein receptors (SNAREs) can be isolated from brain membranes in a complex with endogenous Munc18, consistent with a proposed function of Munc18 in vesicle docking and fusion.
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Affiliation(s)
- Emma Connell
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Frédéric Darios
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Kerensa Broersen
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Naomi Gatsby
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Sew-Yeu Peak-Chew
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Colin Rickman
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
| | - Bazbek Davletov
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
- Tel: +44 1223 402071; Fax: +44 1223 402310; E-mail:
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59
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Rickman C, Medine CN, Bergmann A, Duncan RR. Functionally and spatially distinct modes of munc18-syntaxin 1 interaction. J Biol Chem 2007; 282:12097-103. [PMID: 17264080 PMCID: PMC1891423 DOI: 10.1074/jbc.m700227200] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eukaryotic membrane trafficking is a conserved process under tight temporal and spatial regulation in which the fusion of membranes is driven by the formation of the ternary SNARE complex. Syntaxin 1a, a core component of the exocytic SNARE complex in neurons and neuroendocrine cells, is regulated directly by munc18-1, its cognate Sec1p/munc18 (SM) protein. SM proteins show remarkable structural conservation throughout evolution, indicating a common binding mechanism and function. However, SM proteins possess disparate binding mechanisms and regulatory effects with munc18-1, the major brain isoform, classed as atypical in both its binding specificity and its mode. We now show that munc18-1 interacts with syntaxin 1a through two mechanistically distinct modes of binding, both in vitro and in living cells, in contrast to current models. Furthermore, these functionally divergent interactions occur at distinct cellular locations. These findings provide a molecular explanation for the multiple, spatially distinct roles of munc18-1.
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Affiliation(s)
- Colin Rickman
- Centre for Integrative Physiology, University of Edinburgh, George Square, Edinburgh EH8 9XD, UK
| | - Claire N. Medine
- Centre for Integrative Physiology, University of Edinburgh, George Square, Edinburgh EH8 9XD, UK
| | - Axel Bergmann
- Becker & Hickl GmbH, Nahmitzer Damm 30, 12277 Berlin, Germany
| | - Rory R. Duncan
- Centre for Integrative Physiology, University of Edinburgh, George Square, Edinburgh EH8 9XD, UK
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60
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Shen J, Tareste DC, Paumet F, Rothman JE, Melia TJ. Selective Activation of Cognate SNAREpins by Sec1/Munc18 Proteins. Cell 2007; 128:183-95. [PMID: 17218264 DOI: 10.1016/j.cell.2006.12.016] [Citation(s) in RCA: 365] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2006] [Revised: 10/31/2006] [Accepted: 12/05/2006] [Indexed: 01/11/2023]
Abstract
Sec1/Munc18 (SM) proteins are required for every step of intracellular membrane fusion, but their molecular mechanism of action has been unclear. In this work, we demonstrate a fundamental role of the SM protein: to act as a stimulatory subunit of its cognate SNARE fusion machinery. In a reconstituted system, mammalian SNARE pairs assemble between bilayers to drive a basal fusion reaction. Munc18-1/nSec1, a synaptic SM protein required for neurotransmitter release, strongly accelerates this reaction through direct contact with both t- and v-SNAREs. Munc18-1 accelerates fusion only for the cognate SNAREs for exocytosis, therefore enhancing fusion specificity.
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Affiliation(s)
- Jingshi Shen
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
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61
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Latham CF, Osborne SL, Cryle MJ, Meunier FA. Arachidonic acid potentiates exocytosis and allows neuronal SNARE complex to interact with Munc18a. J Neurochem 2006; 100:1543-54. [PMID: 17181552 DOI: 10.1111/j.1471-4159.2006.04286.x] [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
Neuronal communication relies on the fusion of neurotransmitter-containing vesicles with the neuronal plasma membrane. Recent genetic studies have highlighted the critical role played by polyunsaturated fatty acids in neurotransmission, however, there is little information available about which fatty acids act on exocytosis and, more importantly, by what mechanism. We have used permeabilized chromaffin cells to screen various fatty acids of the n-3 and n-6 series for their acute effects on exocytosis. We have demonstrated that an n-6 series polyunsaturated fatty acid, arachidonic acid, potentiates secretion from intact neurosecretory cells regardless of the secretagogue used. We have shown that arachidonic acid dose dependently increases soluble NSF attachment protein receptor complex formation in chromaffin cells and bovine cortical brain extracts and that a non-hydrolysable analogue of arachidonic acid causes a similar increase in SNARE complex formation. This prompted us to examine the effect of arachidonic acid on SNARE protein interactions with Munc18a, a protein known to prevent Syntaxin1a engagement into the SNARE complex in vitro. In the presence of arachidonic acid, we show that Munc18a can interact with the neuronal SNARE complex in a dose-dependent manner. We further demonstrate that arachidonic acid directly interacts with Syntaxin1a.
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Affiliation(s)
- Catherine F Latham
- Molecular Dynamics of Synaptic Function Laboratory, School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia
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62
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Latham CF, Meunier FA. Munc18a: Munc-y business in mediating exocytosis. Int J Biochem Cell Biol 2006; 39:1576-81. [PMID: 17196873 DOI: 10.1016/j.biocel.2006.11.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 11/16/2006] [Accepted: 11/18/2006] [Indexed: 11/29/2022]
Abstract
The precise sequence of molecular events underlying release of neurotransmitter in neurons is yet to be fully understood. This process, called exocytosis, is tightly controlled by a number of protein-protein and protein-lipid interactions. One such regulatory factor is Munc18a, a cytosolic protein characterized by its interaction with the molecular machinery of exocytosis, primarily with the target SNARE protein, syntaxin1a. While Munc18a interactions have been extensively investigated for more than a decade, the role of Munc18a in vesicular fusion is still not fully defined. In this review, we discuss: (i) the recent analysis of the role of Munc18a in tethering and docking, (ii) the known structural and (iii) functional data surrounding Munc18a interactions with numerous other proteins of the exocytic machinery. Integration of Munc18a regulation by phosphorylation and lipids and the apparent complexity of its pleiotropic functional interactions is critical to deciphering Munc18a's role in exocytosis.
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Affiliation(s)
- Catherine F Latham
- Molecular Dynamics of Synaptic Function Laboratory, School of Biomedical Sciences, The University of Queensland, St. Lucia, Qld 4072, Australia
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63
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Oike H, Wakamori M, Mori Y, Nakanishi H, Taguchi R, Misaka T, Matsumoto I, Abe K. Arachidonic acid can function as a signaling modulator by activating the TRPM5 cation channel in taste receptor cells. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1078-84. [PMID: 16935556 DOI: 10.1016/j.bbalip.2006.07.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Revised: 07/06/2006] [Accepted: 07/13/2006] [Indexed: 11/26/2022]
Abstract
Vertebrate sensory cells such as vomeronasal neurons and Drosophila photoreceptor cells use TRP channels to respond to exogenous stimuli. In mammalian taste cells, bitter and sweet substances as well as some amino acids are received by G protein-coupled receptors (T2Rs or T1Rs). As a result of activation of G protein and phospholipase Cbeta2, the TRPM5 channel is activated. Intracellular Ca(2+) is known to be a TRPM5 activator, but the participation of lipid activators remains unreported. To clarify the effect of arachidonic acid on TRPM5 in taste cells, we investigated the expression profile of a series of enzymes involved in controlling the intracellular free arachidonic acid level, with the result that in a subset of taste bud cells, monoglyceride lipase (MGL) and cyclooxygenase-2 (COX-2) are expressed as well as the previously reported group IIA phospholipase A(2) (PLA(2)-IIA). Double-labeling analysis revealed that MGL, COX-2 and PLA(2)-IIA are co-expressed in some cells that express TRPM5. We then investigated whether arachidonic acid activates TRPM5 via a heterologous expression system in HEK293 cells, and found that its activation occurred at 10 microM arachidonic acid. These results strongly suggest the possibility that arachidonic acid acts as a modulator of TRPM5 in taste signaling pathways.
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Affiliation(s)
- Hideaki Oike
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
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64
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Abstract
Botulinum neurotoxins produced by anaerobic bacteria of the genus Clostridium are the most toxic proteins known, with mouse LD50 values in the 1-5 ng/kg range, and are solely responsible for the pathophysiology of botulism. These metalloproteinases enter peripheral cholinergic nerve terminals and cleave proteins of the neuroexocytosis apparatus, causing a persistent, but reversible, inhibition of neurotransmitter release. They are used in the therapy of many human syndromes caused by hyperactive nerve terminals. Snake presynaptic PLA2 neurotoxins block nerve terminals by binding to the nerve membrane and catalyzing phospholipid hydrolysis with production of lysophospholipids and fatty acids. These compounds change the membrane conformation, causing enhanced fusion of synaptic vesicle via hemifusion intermediate with release of neurotransmitter and, at the same time, inhibition of vesicle fission and recycling. It is possible to envisage clinical applications of the lysophospholipid/fatty acid mixture to inhibit hyperactive superficial nerve terminals.
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Affiliation(s)
- Ornella Rossetto
- Dipartimento di Scienze Biomediche and Istituto CNR di Neuroscienze, Università di Padova, Padova, Italy.
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65
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Darios F, Davletov B. Omega-3 and omega-6 fatty acids stimulate cell membrane expansion by acting on syntaxin 3. Nature 2006; 440:813-7. [PMID: 16598260 DOI: 10.1038/nature04598] [Citation(s) in RCA: 254] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 12/21/2005] [Indexed: 11/09/2022]
Abstract
Growth of neurite processes from the cell body is the critical step in neuronal development and involves a large increase in cell membrane surface area. Arachidonic-acid-releasing phospholipases are highly enriched in nerve growth cones and have previously been implicated in neurite outgrowth. Cell membrane expansion is achieved through the fusion of transport organelles with the plasma membrane; however, the identity of the molecular target of arachidonic acid has remained elusive. Here we show that syntaxin 3 (STX3), a plasma membrane protein, has an important role in the growth of neurites, and also serves as a direct target for omega-6 arachidonic acid. By using syntaxin 3 in a screening assay, we determined that the dietary omega-3 linolenic and docosahexaenoic acids can efficiently substitute for arachidonic acid in activating syntaxin 3. Our findings provide a molecular basis for the previously established action of omega-3 and omega-6 polyunsaturated fatty acids in membrane expansion at the growth cones, and represent the first identification of a single effector molecule for these essential nutrients.
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Affiliation(s)
- Frédéric Darios
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
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66
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Bajohrs M, Darios F, Peak-Chew SY, Davletov B. Promiscuous interaction of SNAP-25 with all plasma membrane syntaxins in a neuroendocrine cell. Biochem J 2006; 392:283-9. [PMID: 15975093 PMCID: PMC1316263 DOI: 10.1042/bj20050583] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
SNAP-25 (25 kDa synaptosome-associated protein) is found in cells that release neurotransmitters and hormones, and plays a central role in the fusion of secretory vesicles with the plasma membrane. SNAP-25 has been shown to interact specifically with syntaxin 1, a 35 kDa membrane protein, to mediate the fusion process. Here, we investigated whether other known syntaxin isoforms found at the plasma membrane can serve as binding partners for SNAP-25 in vivo. In our analysis, we employed rat phaeochromocytoma PC12 cells that are often used as a model of neuronal functions. We now show that these cells contain large amounts of SNAP-25, which interacts not only with syntaxin 1, but also with ubiquitous syntaxins 2, 3 and 4. The plasma membrane syntaxins appear to occupy complementary domains at the plasma membrane. In defined reactions, the ubiquitous plasma membrane syntaxin isoforms, when in binary complexes with SNAP-25, readily bound vesicular synaptobrevin to form SDS-resistant SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) complexes implicated in membrane fusion. However, vesicular synaptotagmin and cytosolic complexin, both implicated in the fusion process, exhibited differential ability to interact with the SNARE complexes formed by syntaxins 1-4, suggesting that the plasma membrane syntaxins may mediate vesicle fusion events with different properties.
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Affiliation(s)
- Mark Bajohrs
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Frédéric Darios
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Sew-Yeu Peak-Chew
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Bazbek Davletov
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
- To whom correspondence should be addressed (email )
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67
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Abstract
In this issue of Chemistry & Biology, Rickman and Davletov suggest a novel mechanism for biological lipids to regulate synaptic transmission in the brain. Physiologically relevant concentrations of arachidonic acid help to dissociate a protein complex involved in exocytosis.
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Affiliation(s)
- Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit, Amsterdam, The Netherlands
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