1
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Murate M, Yokoyama N, Tomishige N, Richert L, Humbert N, Pollet B, Makino A, Kono N, Mauri L, Aoki J, Sako Y, Sonnino S, Komura N, Ando H, Kaneko MK, Kato Y, Inamori KI, Inokuchi JI, Mély Y, Iwabuchi K, Kobayashi T. Cell density-dependent membrane distribution of ganglioside GM3 in melanoma cells. Cell Mol Life Sci 2023; 80:167. [PMID: 37249637 PMCID: PMC11073213 DOI: 10.1007/s00018-023-04813-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/21/2023] [Accepted: 05/17/2023] [Indexed: 05/31/2023]
Abstract
Monosialoganglioside GM3 is the simplest ganglioside involved in various cellular signaling. Cell surface distribution of GM3 is thought to be crucial for the function of GM3, but little is known about the cell surface GM3 distribution. It was shown that anti-GM3 monoclonal antibody binds to GM3 in sparse but not in confluent melanoma cells. Our model membrane study evidenced that monoclonal anti-GM3 antibodies showed stronger binding when GM3 was in less fluid membrane environment. Studies using fluorescent GM3 analogs suggested that GM3 was clustered in less fluid membrane. Moreover, fluorescent lifetime measurement showed that cell surface of high density melanoma cells is more fluid than that of low density cells. Lipidomics and fatty acid supplementation experiment suggested that monounsaturated fatty acid-containing phosphatidylcholine contributed to the cell density-dependent membrane fluidity. Our results indicate that anti-GM3 antibody senses GM3 clustering and the number and/or size of GM3 cluster differ between sparse and confluent melanoma cells.
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Affiliation(s)
- Motohide Murate
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan.
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan.
| | - Noriko Yokoyama
- Institute for Environmental and Gender-Specific Medicine, Graduate School of Medicine, Juntendo University, Urayasu, Chiba, 279-0021, Japan
| | - Nario Tomishige
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Ludovic Richert
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Nicolas Humbert
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Brigitte Pollet
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Asami Makino
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
- Molecular Physiology Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Laura Mauri
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Sandro Sonnino
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Naoko Komura
- Institute for Glyco-Core Research, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Hiromune Ando
- Institute for Glyco-Core Research, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Kei-Ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, 981-8558, Japan
| | - Jin-Ichi Inokuchi
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, 981-8558, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, Toyonaka, Osaka, 560-0043, Japan
| | - Yves Mély
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Kazuhisa Iwabuchi
- Institute for Environmental and Gender-Specific Medicine, Graduate School of Medicine, Juntendo University, Urayasu, Chiba, 279-0021, Japan.
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan.
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan.
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2
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Milanini J, Magdeleine M, Fuggetta N, Ikhlef S, Brau F, Abelanet S, Alpy F, Tomasetto C, Drin G. In situ artificial contact sites (ISACS) between synthetic and endogenous organelle membranes allow for quantification of protein-tethering activities. J Biol Chem 2022; 298:101780. [PMID: 35231443 PMCID: PMC9052148 DOI: 10.1016/j.jbc.2022.101780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 02/16/2022] [Accepted: 02/20/2022] [Indexed: 11/16/2022] Open
Abstract
Membrane contact sites are specialized areas where the membranes of two distinct organelles are physically connected and allow for the exchange of molecules and for signaling processes. Understanding the mechanisms whereby proteins localize to and function in these structures is of special interest; however, methods allowing for reconstitution of these contact sites are few and only based on synthetic membranes and recombinant proteins. Here, we devised a strategy to create in situ artificial contact sites between synthetic and endogenous organelle membranes. Liposomes functionalized with a peptide containing a two phenylalanines in an acidic tract (FFAT) motif were added to adherent cells whose plasma membrane was perforated. Confocal and super-resolution microscopy revealed that these liposomes associated with the endoplasmic reticulum via the specific interaction of the FFAT motif with endoplasmic reticulum–resident vesicle-associated membrane protein–associated proteins. This approach allowed for quantification of the attachment properties of peptides corresponding to FFAT motifs derived from distinct proteins and of a protein construct derived from steroidogenic acute regulatory protein–related lipid transfer domain-3. Collectively, these data indicate that the creation of in situ artificial contact sites represents an efficient approach for studying the membrane-tethering activity of proteins and for designing membrane contact site reconstitution assays in cellular contexts.
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Affiliation(s)
- Julie Milanini
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Maud Magdeleine
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Nicolas Fuggetta
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Souade Ikhlef
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Frédéric Brau
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Sophie Abelanet
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France
| | - Fabien Alpy
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique UMR7104, Institut National de la Santé et de la Recherche Médicale U1258, Université de Strasbourg, Illkirch, France
| | - Catherine Tomasetto
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique UMR7104, Institut National de la Santé et de la Recherche Médicale U1258, Université de Strasbourg, Illkirch, France
| | - Guillaume Drin
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Valbonne, France.
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3
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Sakla M, Breitinger U, Breitinger HG, Mansour S, Tammam SN. Delivery of trans-membrane proteins by liposomes; the effect of liposome size and formulation technique on the efficiency of protein delivery. Int J Pharm 2021; 606:120879. [PMID: 34265391 DOI: 10.1016/j.ijpharm.2021.120879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 06/29/2021] [Accepted: 07/09/2021] [Indexed: 01/06/2023]
Abstract
Channelopathies are disorders caused by reduced expression or impaired function of ion channels. Most current therapies rely on symptomatic treatment without addressing the underlying cause. We have recently established proof of principle for delivery of functional ion channel protein into the membrane of target cells using fusogenic liposomes incorporating glycine receptor (GlyR)-containing cell membrane fragments (CMF) that were formulated by thin film hydration. Here, the effect of liposome size and the formulation technique on the performance of the delivery vehicle was assessed. Three types of liposomes were prepared using lecithin and cholesterol, (i) small (SL), and (ii) large (LL) liposomes made by thin film hydration, and (iii) small liposomes prepared by vortex agitation (V-SL). All liposomes were evaluated for their ability to (i) incorporate GlyR-rich CMF, (ii) fuse with the cell membrane of target cells and (iii) deliver functional GlyR, as assessed by patch-clamp electrophysiology. SL prepared by thin film hydration offered the most effective delivery of glycine receptors that gave clear glycine-mediated currents in target cells. LL showed higher incorporation of CMF, but did not effectively fuse with the target cell membrane, while V-SL did not incorporate sufficient amounts of CMF. Additionally, SL showed minimalin vivotoxicity upon intrathecal injection in mice. Thus, liposome-mediated delivery of membrane proteins may be a promising therapeutic approach for the treatment of channelopathies.
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Affiliation(s)
- Monica Sakla
- Department of Pharmaceutical Technology, The German University in Cairo (GUC), Cairo, Egypt
| | - Ulrike Breitinger
- Department of Biochemistry, The German University in Cairo (GUC), Cairo, Egypt
| | | | - Samar Mansour
- Department of Pharmaceutical Technology, The German University in Cairo (GUC), Cairo, Egypt
| | - Salma N Tammam
- Department of Pharmaceutical Technology, The German University in Cairo (GUC), Cairo, Egypt.
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4
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Environment-Sensitive Fluorescence of 7-Nitrobenz-2-oxa-1,3-diazol-4-yl (NBD)-Labeled Ligands for Serotonin Receptors. Molecules 2021; 26:molecules26133848. [PMID: 34202630 PMCID: PMC8270269 DOI: 10.3390/molecules26133848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/19/2021] [Accepted: 06/21/2021] [Indexed: 12/21/2022] Open
Abstract
Serotonin is a neurotransmitter that plays a crucial role in the regulation of several behavioral and cognitive functions by binding to a number of different serotonin receptors present on the cell surface. We report here the synthesis and characterization of several novel fluorescent analogs of serotonin in which the fluorescent NBD (7-nitrobenz-2-oxa-1,3-diazol-4-yl) group is covalently attached to serotonin. The fluorescent ligands compete with the serotonin1A receptor specific radiolabeled agonist for binding to the receptor. Interestingly, these fluorescent ligands display a high environmental sensitivity of their fluorescence. Importantly, the human serotonin1A receptor stably expressed in CHO-K1 cells could be specifically labeled with one of the fluorescent ligands with minimal nonspecific labeling. Interestingly, we show by spectral imaging that the NBD-labeled ligand exhibits a red edge excitation shift (REES) of 29 nm when bound to the receptor, implying that it is localized in a restricted microenvironment. Taken together, our results show that NBD-labeled serotonin analogs offer an attractive fluorescent approach for elucidating the molecular environment of the serotonin binding site in serotonin receptors. In view of the multiple roles played by the serotonergic systems in the central and peripheral nervous systems, these fluorescent ligands would be useful in future studies involving serotonin receptors.
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5
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Raghuraman H, Chatterjee S, Das A. Site-Directed Fluorescence Approaches for Dynamic Structural Biology of Membrane Peptides and Proteins. Front Mol Biosci 2019; 6:96. [PMID: 31608290 PMCID: PMC6774292 DOI: 10.3389/fmolb.2019.00096] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 09/11/2019] [Indexed: 12/31/2022] Open
Abstract
Membrane proteins mediate a number of cellular functions and are associated with several diseases and also play a crucial role in pathogenicity. Due to their importance in cellular structure and function, they are important drug targets for ~60% of drugs available in the market. Despite the technological advancement and recent successful outcomes in determining the high-resolution structural snapshot of membrane proteins, the mechanistic details underlining the complex functionalities of membrane proteins is least understood. This is largely due to lack of structural dynamics information pertaining to different functional states of membrane proteins in a membrane environment. Fluorescence spectroscopy is a widely used technique in the analysis of functionally-relevant structure and dynamics of membrane protein. This review is focused on various site-directed fluorescence (SDFL) approaches and their applications to explore structural information, conformational changes, hydration dynamics, and lipid-protein interactions of important classes of membrane proteins that include the pore-forming peptides/proteins, ion channels/transporters and G-protein coupled receptors.
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Affiliation(s)
- H. Raghuraman
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Kolkata, India
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6
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Morriswood B, Hoeller O. Resurrection science. EMBO Rep 2018; 19:embr.201846577. [PMID: 29950517 DOI: 10.15252/embr.201846577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Brooke Morriswood
- Department of Cell & Developmental Biology, University of Würzburg, Würzburg, Germany
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7
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Probing and manipulating intracellular membrane traffic by microinjection of artificial vesicles. Proc Natl Acad Sci U S A 2017; 114:E9883-E9892. [PMID: 29087339 PMCID: PMC5699080 DOI: 10.1073/pnas.1713524114] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
There is still a large gap in our understanding between the functional complexity of cells and the reconstruction of partial cellular functions in vitro from purified or engineered parts. Here we have introduced artificial vesicles of defined composition into living cells to probe the capacity of the cellular cytoplasm in dealing with foreign material and to develop tools for the directed manipulation of cellular functions. Our data show that protein-free liposomes, after variable delay times, are captured by the Golgi apparatus that is reached either by random diffusion or, in the case of large unilamellar vesicles, by microtubule-dependent transport via a dynactin/dynein motor complex. However, insertion of early endosomal SNARE proteins suffices to convert liposomes into trafficking vesicles that dock and fuse with early endosomes, thus overriding the default pathway to the Golgi. Moreover, such liposomes can be directed to mitochondria expressing simple artificial affinity tags, which can also be employed to divert endogenous trafficking vesicles. In addition, fusion or subsequent acidification of liposomes can be monitored by incorporation of appropriate chemical sensors. This approach provides an opportunity for probing and manipulating cellular functions that cannot be addressed by conventional genetic approaches. We conclude that the cellular cytoplasm has a remarkable capacity for self-organization and that introduction of such macromolecular complexes may advance nanoengineering of eukaryotic cells.
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8
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Sumi M, Makino A, Inaba T, Sako Y, Fujimori F, Greimel P, Kobayashi T. Photoswitchable phospholipid FRET acceptor: Detergent free intermembrane transfer assay of fluorescent lipid analogs. Sci Rep 2017; 7:2900. [PMID: 28588242 PMCID: PMC5460167 DOI: 10.1038/s41598-017-02980-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 04/20/2017] [Indexed: 12/20/2022] Open
Abstract
We have developed and characterized a novel photoswitchable phospholipid analog termed N-nitroBIPS-DPPG. The fluorescence can be switched on and off repeatedly with minimal photobleaching by UV or visible light exposure, respectively. The rather large photochromic head group is inserted deeply into the interfacial membrane region conferring a conical overall lipid shape, preference for a positive curvature and only minimal intermembrane transfer. Utilizing the switchable NBD fluorescence quenching ability of N-nitroBIPS-DPPG, a detergent free intermembrane transfer assay system for NBD modified lipids was demonstrated and validated. As NBD quenching can be turned off, total NBD associated sample fluorescence can be determined without the need of detergents. This not only reduces detergent associated systematic errors, but also simplifies assay handling and allows assay extension to detergent insoluble lipid species.
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Affiliation(s)
- Mariko Sumi
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.,Graduate School of Humanities and Life Sciences, Tokyo Kasei University, 1-18-1, Kaga, Itabashi, Tokyo, 173-8602, Japan
| | - Asami Makino
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.,Cellular Informatics Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
| | - Takehiko Inaba
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.,Cellular Informatics Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
| | - Fumihiro Fujimori
- Graduate School of Humanities and Life Sciences, Tokyo Kasei University, 1-18-1, Kaga, Itabashi, Tokyo, 173-8602, Japan
| | - Peter Greimel
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan. .,UMR 7213 CNRS, University of Strasbourg, 67401, Illkirch, France.
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9
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Magdeleine M, Gautier R, Gounon P, Barelli H, Vanni S, Antonny B. A filter at the entrance of the Golgi that selects vesicles according to size and bulk lipid composition. eLife 2016; 5. [PMID: 27458799 PMCID: PMC4961469 DOI: 10.7554/elife.16988] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 07/12/2016] [Indexed: 12/22/2022] Open
Abstract
When small phosphatidylcholine liposomes are added to perforated cells, they bind preferentially to the Golgi suggesting an exceptional avidity of this organelle for curved membranes without stereospecific interactions. We show that the cis golgin GMAP-210 accounts for this property. First, the liposome tethering properties of the Golgi resembles that of the amphipathic lipid-packing sensor (ALPS) motif of GMAP-210: both preferred small (radius < 40 nm) liposomes made of monounsaturated but not saturated lipids. Second, reducing GMAP-210 levels or redirecting its ALPS motif to mitochondria decreased liposome capture by the Golgi. Extensive mutagenesis analysis suggests that GMAP-210 tethers authentic transport vesicles via the same mechanism whereby the ALPS motif senses lipid-packing defects at the vesicle surface through its regularly spaced hydrophobic residues. We conclude that the Golgi uses GMAP-210 as a filter to select transport vesicles according to their size and bulk lipid composition. DOI:http://dx.doi.org/10.7554/eLife.16988.001
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Affiliation(s)
- Maud Magdeleine
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Romain Gautier
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Pierre Gounon
- Centre Commun de Microscopie Appliquée, Université Côte d'Azur, Nice, France
| | - Hélène Barelli
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Stefano Vanni
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Bruno Antonny
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
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10
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Kasimanickam VR, Buhr MM. Fusion of Boar Sperm with Nanoliposomes Prepared from Synthetic Phospholipids. Reprod Domest Anim 2016; 51:461-6. [PMID: 27217373 DOI: 10.1111/rda.12702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 04/09/2016] [Indexed: 11/30/2022]
Abstract
Liposomes are artificial membrane vesicles that can be used to test and model the functions and interactions of various biological membranes, or as a carrier system to deliver biologically active substances into the cells, or to incorporate lipids into the plasma membrane of target cells to modify membrane structure-function relationships. Sperm plasma membrane undergoes lipid modification during maturation in epididymis and during capacitation in the female reproductive tract to facilitate fertilization. Natural variation in the amounts and composition of lipids in the sperm plasma membrane may also contribute to the species-specific sperm sensitivities to handling and storage conditions. Boar sperm are notoriously susceptible to membrane damage and are resistant to compositional alteration by artificial liposomes. This study used flow cytometry to demonstrate stable incorporation of nanoliposomes prepared from a complex mixture of various phospholipids (phosphatidylcholine : phosphatidylethanolamine : sphingomyelin : phosphatidylserine : phosphatidylinositol) with high fusion efficiency. Over 90% of sperm rapidly took up fluorescently labelled liposomes and retained the lipids for at least 60 min, in a significant time- and concentration-dependent manner. This unique fusion efficacy could be used to alter sperm plasma membrane composition and hence membrane-based functional responses.
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Affiliation(s)
- V R Kasimanickam
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - M M Buhr
- College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK, Canada
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11
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Ueda Y, Makino A, Murase‐Tamada K, Sakai S, Inaba T, Hullin‐Matsuda F, Kobayashi T. Sphingomyelin regulates the transbilayer movement of diacylglycerol in the plasma membrane of Madin‐Darby canine kidney cells. FASEB J 2013; 27:3284-97. [DOI: 10.1096/fj.12-226548] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Yoshibumi Ueda
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
| | - Asami Makino
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
| | | | - Shota Sakai
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
| | - Takehiko Inaba
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
| | - Françoise Hullin‐Matsuda
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1060Université Lyon 1VilleurbanneFrance
| | - Toshihide Kobayashi
- Lipid Biology LaboratoryRikagaku Kenkyūjo (RIKEN)WakoJapan
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1060Université Lyon 1VilleurbanneFrance
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12
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Matsunaga S, Matsunaga T, Iwamoto K, Yamada T, Shibayama M, Kawai M, Kobayashi T. Visualization of phospholipid particle fusion induced by duramycin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:8200-8207. [PMID: 19432393 DOI: 10.1021/la900616c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We visualized nanometer-scale phospholipid particle fusion by scanning tunneling microscopy (STM) on an alkanethiol-modified gold substrate, induced by duramycin, a tetracyclic antibiotic peptide with 19 amino residues. Ultrasonic homogenization generated a suspension mainly consisting of minimal lipid particles (MLP) from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) in a phosphate buffer solution, confirmed by dynamic light scattering (DLS). In situ STM discerned individual MLP as particles (diameter approximately 8 nm) spread on Au(111), modified with alkanethiol, within the suspension. The MLP became fragile by the presence of duramycin, and the MLP were easily scratched by the scanning tip into multilayers along the surface. This process of particle fusion on the gold surface coincides with the aggregation of MLP in the suspension, observed by DLS. It was demonstrated that STM is capable of discerning and monitoring the nanometer-scale features of phospholipid particles altered by antibiotics with biochemical impact. STM might allow in situ, real-space, nanometer-scale observations of minute particles composed of phospholipids within the real cells with the highest magnification ratio.
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Affiliation(s)
- Soichiro Matsunaga
- Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, 277-8561, Japan
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13
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14
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Poot M. Analysis of intracellular organelles by flow cytometry or microscopy. ACTA ACUST UNITED AC 2008; Chapter 9:Unit 9.4. [PMID: 18770757 DOI: 10.1002/0471142956.cy0904s14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Functional analysis of cellular organelles can be accomplished by staining cells with suitable organelle-specific dyes and analyzing the fluorescence of the stained cells with a flow cytometer. With this methodology it is possible to resolve suspected heterogeneity in organelle function or content within a population of cells. Morphological information can be provided by quantitative microscopy (confocal microscope or video microscope with digital image-analysis system). The thirteen protocols cover flow cytometry and microscopy for both live and fixed cells.
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Affiliation(s)
- M Poot
- University of Washington, Seattle, Washington, USA
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15
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Raghuraman H, Shrivastava S, Chattopadhyay A. Monitoring the looping up of acyl chain labeled NBD lipids in membranes as a function of membrane phase state. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1258-67. [PMID: 17362875 DOI: 10.1016/j.bbamem.2007.02.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 01/21/2007] [Accepted: 02/01/2007] [Indexed: 11/18/2022]
Abstract
Lipids that are labeled with the NBD (7-nitrobenz-2-oxa-1,3-diazol-4-yl) group are widely used as fluorescent analogues of native lipids in biological and model membranes to monitor a variety of processes. The NBD group of acyl chain labeled NBD lipids is known to loop up to the membrane interface in fluid phase membranes. However, the organization of these lipids in gel phase membranes is not resolved. In this paper, we monitored the influence of the membrane phase state on the looping up behavior of acyl chain labeled NBD lipids utilizing red edge excitation shift (REES) and other sensitive fluorescence approaches. Interestingly, our REES results indicate that NBD group of lipids, which are labeled at the fatty acyl region, resides in the more hydrophobic region in gel phase membranes, and complete looping of the NBD group occurs only in the fluid phase. This is supported by other fluorescence parameters such as polarization and lifetime. Taken together, our results demonstrate that membrane packing, which depends on temperature and the phase state of the membrane, significantly affects the localization of acyl chain labeled NBD lipids. In view of the wide ranging use of NBD-labeled lipids in cell and membrane biology, these results could have potentially important implications in future studies involving these lipids as tracers.
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Affiliation(s)
- H Raghuraman
- Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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16
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Pipalia NH, Hao M, Mukherjee S, Maxfield FR. Sterol, protein and lipid trafficking in Chinese hamster ovary cells with Niemann-Pick type C1 defect. Traffic 2006; 8:130-41. [PMID: 17156101 DOI: 10.1111/j.1600-0854.2006.00513.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We studied the trafficking of sterols, lipids and proteins in Niemann-Pick type C (NPC) cells. The NPC is an inherited disorder involving the accumulation of sterol and lipids in modified late-endosome/lysosome-like storage organelles. Most sterol accumulation studies in NPC cells have been carried out using low-density lipoprotein (LDL) as the sterol source, and it has been shown that sterol efflux from late endosomes is impaired in NPC cells. In this study, we used a fluorescent sterol analog, dehydroergosterol, which can be quickly and efficiently delivered to the plasma membrane. Thus, we were able to study the trafficking kinetics of the non-LDL-derived sterol pool, and we found that dehydroergosterol accumulates in the storage organelles over the course of several hours in NPC cells. We also found that dialkylindocarbocyanine lipid-mimetic analogs that recycle efficiently from early endosomes in wild-type cells are targeted to late endosomal organelles in NPC cells, and transferrin receptors recycle slowly and inefficiently in NPC cells. These data are consistent with multiple trafficking defects in both early and late endosomes in NPC cells.
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Affiliation(s)
- Nina H Pipalia
- Department of Biochemistry, Weill Medical College of Cornell University, New York, NY 10021, USA
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17
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Sato SB, Ishii K, Makino A, Iwabuchi K, Yamaji-Hasegawa A, Senoh Y, Nagaoka I, Sakuraba H, Kobayashi T. Distribution and Transport of Cholesterol-rich Membrane Domains Monitored by a Membrane-impermeant Fluorescent Polyethylene Glycol-derivatized Cholesterol. J Biol Chem 2004; 279:23790-6. [PMID: 15026415 DOI: 10.1074/jbc.m313568200] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cholesterol-rich membrane domains function in various membrane events as diverse as signal transduction and membrane traffic. We studied the interaction of a fluorescein ester of polyethylene glycol-derivatized cholesterol (fPEG-Chol) with cholesterol-rich membranes both in cells and in model membranes. Unlike filipin and other cholesterol probes, this molecule could be applied as an aqueous dispersion to various samples. When added to live cells, fPEG-Chol distributed exclusively in the outer plasma membrane leaflet and was enriched in microdomains that dynamically clustered by the activation of receptor signaling. The surface-bound fPEG-Chol was slowly internalized via clathrin-independent pathway into endosomes together with lipid raft markers. Noteworthy, fPEG-Chol could be microinjected in the living cells in which we found Golgi apparatus as the sole major organelle to be labeled. PEG-Chol, thus, provides a novel, sensitive probe for unraveling the dynamics of cholesterol-rich microdomains in living cells.
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18
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Makino A, Baba T, Fujimoto K, Iwamoto K, Yano Y, Terada N, Ohno S, Sato SB, Ohta A, Umeda M, Matsuzaki K, Kobayashi T. Cinnamycin (Ro 09-0198) promotes cell binding and toxicity by inducing transbilayer lipid movement. J Biol Chem 2003; 278:3204-9. [PMID: 12446685 DOI: 10.1074/jbc.m210347200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cinnamycin is a unique toxin in that its receptor, phosphatidylethanolamine (PE), resides in the inner layer of the plasma membrane. Little is known about how the toxin recognizes PE and causes cytotoxicity. We showed that cinnamycin induced transbilayer phospholipid movement in target cells that leads to the exposure of inner leaflet PE to the toxin. Model membrane studies revealed that cinnamycin induced transbilayer lipid movement in a PE concentration-dependent manner. Re-orientation of phospholipids was accompanied by an increase in the incidence of beta-sheet structure in cinnamycin. When the surface concentration of PE was high, cinnamycin induced membrane re-organization such as membrane fusion and the alteration of membrane gross morphology. These results suggest that cinnamycin promotes its own binding to the cell and causes toxicity by inducing transbilayer lipid movement.
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Affiliation(s)
- Asami Makino
- Supra-Biomolecular System Research Group, RIKEN Institute of Physical and Chemical Research, Frontier Research System, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
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19
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Affiliation(s)
- Nejat Düzgüneş
- Department of Microbiology, School of Dentistry, University of the Pacific, 2155 Webster Street, San Francisco, California 94115, USA
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20
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Scott BL, Van Komen JS, Liu S, Weber T, Melia TJ, McNew JA. Liposome fusion assay to monitor intracellular membrane fusion machines. Methods Enzymol 2003; 372:274-300. [PMID: 14610819 DOI: 10.1016/s0076-6879(03)72016-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Brenton L Scott
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, USA
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21
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Takeda Y, Kasamo K. In vitro fusion of plant Golgi membranes can be influenced by divalent cations. J Biol Chem 2002; 277:47756-64. [PMID: 12368278 DOI: 10.1074/jbc.m209199200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The fusogenic activity of plant Golgi membranes was studied in a cell-free system by assaying lipid mixing and content leakages of fluorescence probes. Golgi membranes from mung bean (Vigna radiata L.) hypocotyl cells fused to liposomes in the absence of any cytosolic proteins and nucleotides. It was demonstrated that the fusion was mediated by integral membrane protein(s), and was influenced by divalent cations (mm). Mg(2+), Ca(2+), and Mn(2+) ions enhanced the lipid mixing by reducing repulsive forces between membranes. In the content leakage assay, Mg(2+) ions also showed a stimulative effect. However, other divalent cations were inhibitory. It is suggested that the fusion system of Golgi membranes comprises at least two components: one that mediates the formation of fusion intermediates prior to pore opening, and one that mediates the subsequent processes. The latter must be sensitive to divalent cations at millimolar concentrations. The fusion of Golgi and biological membranes was induced by divalent cations. We speculated about the biological role of the fusion system studied here.
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Affiliation(s)
- Yuichi Takeda
- Research Institute for Bioresources, Okayama University, 1-20-2 Chuo, Kurashiki 710-0046, Japan.
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22
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Rukmini R, Rawat SS, Biswas SC, Chattopadhyay A. Cholesterol organization in membranes at low concentrations: effects of curvature stress and membrane thickness. Biophys J 2001; 81:2122-34. [PMID: 11566783 PMCID: PMC1301684 DOI: 10.1016/s0006-3495(01)75860-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cholesterol is often found distributed nonrandomly in domains in biological and model membranes and has been reported to be distributed heterogeneously among various intracellular membranes. Although a large body of literature exists on the organization of cholesterol in plasma membranes or membranes with high cholesterol content, very little is known about organization of cholesterol in membranes containing low amounts of cholesterol. Using a fluorescent cholesterol analog (25-[N-[(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-methyl]amino]-27-norcholesterol, or NBD-cholesterol), we have previously shown that cholesterol may exhibit local organization even at very low concentrations in membranes, which could possibly be attributable to transbilayer tail-to-tail dimers. This is supported by similar observations reported by other groups using cholesterol or dehydroergosterol, a naturally occurring fluorescent cholesterol analog which closely mimics cholesterol. In this paper, we have tested the basic features of cholesterol organization in membranes at low concentrations using spectral features of dehydroergosterol. More importantly, we have investigated the role of membrane surface curvature and thickness on transbilayer dimer arrangement of cholesterol using NBD-cholesterol. We find that dimerization is not favored in membranes with high curvature. However, cholesterol dimers are observed again if the curvature stress is relieved. Further, we have monitored the effect of membrane thickness on the dimerization process. Our results show that the dimerization process is stringently controlled by a narrow window of membrane thickness. Interestingly, this type of local organization of NBD-cholesterol at low concentrations is also observed in sphingomyelin-containing membranes. These results could be significant in membranes that have very low cholesterol content, such as the endoplasmic reticulum and the inner mitochondrial membrane, and in trafficking and sorting of cellular cholesterol.
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Affiliation(s)
- R Rukmini
- Centre for Cellular & Molecular Biology, Hyderabad 500 007, India
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23
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Rao M, Alving CR. Delivery of lipids and liposomal proteins to the cytoplasm and Golgi of antigen-presenting cells. mangala.rao@na.amedd.army.mil. Adv Drug Deliv Rev 2000; 41:171-88. [PMID: 10699313 DOI: 10.1016/s0169-409x(99)00064-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Liposomes have the well-known ability to channel protein and peptide antigens into the MHC class II pathway of phagocytic antigen-presenting cells (APCs) and thereby enhance the induction of antibodies and antigen-specific T cell proliferative responses. Liposomes also serve as an efficient delivery system for entry of exogenous protein and peptide antigens into the MHC class I pathway and thus are very efficient inducers of cytotoxic T cell responses. Soluble antigens that are rendered particulate by encapsulation in liposomes are localized both in vacuoles and in the cytoplasm of bone marrow-derived macrophages. Utilizing fluorophore-labeled proteins encapsulated in liposomes we have addressed the question of how liposomal antigens enter the MHC class I pathway. After phagocytosis of the liposomes, the fluorescent liposomal protein and liposomal lipids enter the cytoplasm where they are processed by the proteasome complex. The processed liposomal protein is then transported via the TAP complex into the endoplasmic reticulum and the Golgi complex. Both the liposomal lipids and the liposomal proteins appear to follow the same intracellular route and they are processed as a protein-lipid unit. In the absence of a protein antigen (empty liposomes), there is no organelle-specific localization of the liposomal lipids. In contrast, when a protein is encapsulated in these liposomes, the distribution of the liposomal lipids is dramatically affected and the liposomal lipids localize to the trans-Golgi area. Localization of the protein in the trans-Golgi area requires liposomal lipids. Similarly, for the localization of liposomal lipids in the trans-Golgi area, there is an obligatory requirement for protein. Therefore, the intracellular trafficking patterns of liposomal lipids and liposomal protein are reciprocally regulated. Presence of both liposomal lipids and liposomal protein in the trans-Golgi therefore facilitates the entry of liposomal antigens into the MHC class I pathway. It is also possible that liposomal lipids are presented to T cells via the recently described CD1 pathway for lipid antigens. Because liposome-formulated vaccines have the potential to stimulate antibody as well as cellular immune responses to protein and lipid components, this approach could prove to be extremely useful in designing vaccine strategies.
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Affiliation(s)
- M Rao
- Department of Membrane Biochemistry, Bldg. 40, Walter Reed Army Institute of Research, Washington, DC 20307-5100, USA
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24
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Kumar NS, Mansbach CM. Prechylomicron transport vesicle: isolation and partial characterization. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:G378-86. [PMID: 9950811 DOI: 10.1152/ajpgi.1999.276.2.g378] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
The intestine is able to regulate its output rate of chylomicrons, the major intestinal triacylglycerol (TG) transport vehicle. We have proposed that a vesicle, transporting the developing chylomicron from the endoplasmic reticulum (ER) to the Golgi, is the rate-limiting step in the process of TG transit through the enterocyte [Am. J. Physiol. 273 (Gastrointest. Liver Physiol. 36): G18-G30, 1997]. We wished to isolate and characterize this vesicle. The apical portion of rat intestinal cells were avulsed, and the mucosa was stirred in buffer. The supernatant was centrifuged in two different sucrose gradients, and the top 2.5 ml of the last gradient were collected and concentrated. Electron microscopy showed a 200-nm vesicle. The vesicle contained immunoidentifiable apolipoprotein (apo) B48 and apo A-IV but very little apo A-I, although apo A-I was present in the ER and Golgi. [3H]TG-loaded vesicles delivered [3H]TG to the Golgi but not the ER. Marker enzyme assays also indicate that the isolated fraction is different from the ER and Golgi fractions. We conclude that we have isolated a vesicle that is post-ER but pre-Golgi that vectorially transports TG to the Golgi.
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Affiliation(s)
- N S Kumar
- Department of Medicine, Division of Gastroenterology University of Tennessee, Memphis 38163; and Veterans Affairs Medical Center, Memphis, Tennessee 38104, USA
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25
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Rao M, Rothwell SW, Wassef NM, Koolwal AB, Alving CR. Trafficking of liposomal antigen to the trans-Golgi of murine macrophages requires both liposomal lipid and liposomal protein. Exp Cell Res 1999; 246:203-11. [PMID: 9882529 DOI: 10.1006/excr.1998.4274] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Major histocompatibility complex (MHC) class I molecules found on antigen-presenting cells present peptides derived from cytoplasmic proteins to T cells. In contrast, peptides from exogenous proteins are mostly presented by class II molecules. It has been well established that liposomes can serve as an efficient delivery system for entry of exogenous protein antigens into the MHC class I pathway. Our previous studies utilizing fluorophore-labeled proteins encapsulated in liposomes demonstrated that after phagocytosis of the liposomes by bone marrow-derived macrophages (BMs), the processed peptides were subsequently visualized in the trans-Golgi, while free conalbumin was excluded from the trans-Golgi area. In the present study, we investigated whether liposomal lipids follow the same intracellular route as the liposomal proteins after phagocytosis by BMs. Multilamellar liposomes with different lipid compositions that also contained fluorescent phospholipids (empty liposomes) were incubated with murine BMs. Our results indicate that although empty liposomes were avidly phagocytosed by macrophages, the fluorescent liposomal lipids did not localize to any particular area of the cell but were distributed throughout the cell. In contrast, when a protein was encapsulated in the liposomes, the liposomal lipids were no longer dispersed throughout the cell, but were concentrated and localized in the trans-Golgi area. Furthermore, when the liposomes contained a fluorescent-labeled protein, the fluorescent peptides also localized to the trans-Golgi. These results demonstrate that the combination of both liposomal lipids and liposomal protein is required for Golgi-specific targeting of liposomal antigens. Transport of both liposomal lipids and liposomal proteins to the Golgi complex, a major subcellular organelle in the passage of MHC class I molecules, might explain why antigens encapsulated in liposomes readily induce cytotoxic T lymphocytes.
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Affiliation(s)
- M Rao
- Department of Membrane Biochemistry, Walter Reed Army Institute of Research, Washington, DC, 20307-5100, USA.
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26
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Karolin J, Bogen ST, Johansson LB�, Molotkovsky JG. Polarized fluorescence and absorption spectroscopy of 1,32-dihydroxy-dotriacontane-bis-rhodamine 101 ester. A new and lipid bilayer-spanning probe. J Fluoresc 1995; 5:279-84. [DOI: 10.1007/bf00723899] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/1994] [Revised: 10/10/1994] [Accepted: 10/20/1994] [Indexed: 10/26/2022]
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27
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Alving CR. Liposomal vaccines: clinical status and immunological presentation for humoral and cellular immunity. Ann N Y Acad Sci 1995; 754:143-52. [PMID: 7625648 DOI: 10.1111/j.1749-6632.1995.tb44447.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Liposomes have been proposed as vehicles for vaccines against parasitic and viral illnesses. Experimental vaccines against malaria, HIV, hepatitis A, and influenza virus have been shown to be safe and highly immunogenic in several human trials. Analysis of the intracellular trafficking patterns of liposomal antigen reveals that after being phagocytosed by macrophages, liposomal antigen readily escapes from endosomes into the cytoplasm of the macrophages. It is proposed that liposomal peptide antigen can enter either the Golgi apparatus or the endoplasmic reticulum and thereby interact with MHC class II or class I molecules. The intracellular cytoplasmic trafficking patterns of liposomal antigens raise the possibility that liposomes may have utility in human vaccines for induction of either humoral immunity or cytotoxic T lymphocytes.
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Affiliation(s)
- C R Alving
- Department of Membrane Biochemistry, Walter Reed Army Institute of Research, Washington, DC 20307-5100, USA
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28
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Seksek O, Biwersi J, Verkman AS. Direct measurement of trans-Golgi pH in living cells and regulation by second messengers. J Biol Chem 1995; 270:4967-70. [PMID: 7890600 DOI: 10.1074/jbc.270.10.4967] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In the endocytic compartment, an acidic pH plays a key role in receptor and ligand sorting, vesicular transport, and protein degradation. In the secretory compartment, indirect estimates of trans-Golgi pH based on partitioning of weak bases and following viral infection suggest a mildly acidic pH of > 6.0. We developed a liposome microinjection method to introduce fluorescent indicators into the aqueous compartment of trans-Golgi in living cells. In the presence of ATP and at 37 degrees C, 70-nm diameter liposomes delivered their fluid-phase contents selectively into the trans-Golgi compartment as assessed by colocalization with the trans-Golgi stain N-[6-[(7-nitrobenz-2-oxa-1, 3-diazol-4-yl)amino]caproyl]-sphingosine (C6-NBD-ceramide). Liposome fusion was ATP- and temperature-dependent and blocked by N-ethylmaleimide but not by guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S). trans-Golgi pH in skin fibroblasts was 6.17 +/- 0.02 (S.E., n = 174) as measured by ratio imaging confocal microscopy using fluorescein and rhodamine-based indicators and an in vivo calibration procedure. trans-Golgi pH increased to 6.8 +/- 0.1 by cAMP agonists and to 6.5 +/- 0.1 by protein kinase C activation. These results provide the first direct measurement of trans-Golgi pH in living cells and demonstrate pH regulation by second messengers.
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Affiliation(s)
- O Seksek
- Department of Medicine, University of California, San Francisco 94143-0521
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29
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Moreau P, Cassagne C. Phospholipid trafficking and membrane biogenesis. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1197:257-90. [PMID: 7819268 DOI: 10.1016/0304-4157(94)90010-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- P Moreau
- URA 1811 CNRS, IBGC, University of Bordeaux II, France
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30
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31
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Martin OC, Pagano RE. Internalization and sorting of a fluorescent analogue of glucosylceramide to the Golgi apparatus of human skin fibroblasts: utilization of endocytic and nonendocytic transport mechanisms. J Cell Biol 1994; 125:769-81. [PMID: 8188745 PMCID: PMC2120081 DOI: 10.1083/jcb.125.4.769] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We examined the uptake and intracellular transport of the fluorescent glucosylceramide analogue N-[5-(5,7-dimethyl BODIPYTM)-1-pentanoyl]-glucosyl sphingosine (C5-DMB-GlcCer) in human skin fibroblasts, and we compared its behavior to that of the corresponding fluorescent analogues of sphingomyelin, galactosylceramide, and lactosylceramide. All four fluorescent analogues were readily transferred from defatted BSA to the plasma membrane during incubation at 4 degrees C. When cells treated with C5-DMB-GlcCer were washed, warmed to 37 degrees C, and subsequently incubated with defatted BSA to remove fluorescent lipid at the cell surface, strong fluorescence was observed at the Golgi apparatus, as well as weaker labeling at the nuclear envelope and other intracellular membranes. Similar results were obtained with C5-DMB-galactosylceramide, except that labeling of the Golgi apparatus was weaker than with C5-DMB-GlcCer. Internalization of C5-DMB-GlcCer was not inhibited by various treatments, including ATP depletion or warming to 19 degrees C, and biochemical analysis demonstrated that the lipid was not metabolized during its internalization. However, accumulation of C5-DMB-GlcCer at the Golgi apparatus was reduced when cells were treated with a nonfluorescent analogue of glucosylceramide, suggesting that accumulation of C5-DMB-GlcCer at the Golgi apparatus was a saturable process. In contrast, cells treated with C5-DMB-analogues of sphingomyelin or lactosylceramide internalized the fluorescent lipid into a punctate pattern of fluorescence during warming at 37 degrees C, and this process was temperature and energy dependent. These results with C5-DMB-sphingomyelin and C5-DMB-lactosylceramide were analogous to those obtained with another fluorescent analogue of sphingomyelin in which labeling of endocytic vesicles and plasma membrane lipid recycling were documented (Koval, M., and R. E. Pagano. 1990. J. Cell Biol. 111:429-442). Incubation of perforated cells with C5-DMB-sphingomyelin resulted in prominent labeling of the nuclear envelope and other intracellular membranes, similar to the pattern observed with C5-DMB-GlcCer in intact cells. These observations are consistent with the transbilayer movement of fluorescent analogues of glucosylceramide and galactosylceramide at the plasma membrane and early endosomes of human skin fibroblasts, and suggest that both endocytic and nonendocytic pathways are used in the internalization of these lipids from the plasma membrane.
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Affiliation(s)
- O C Martin
- Department of Embryology, Carnegie Institution of Washington, Baltimore, Maryland 21210-3399
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32
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Wattenberg BW. Reconstitution of Glycolipid Transport between Compartments of the Golgi in a Cell-Free System. CURRENT TOPICS IN MEMBRANES 1994. [DOI: 10.1016/s0070-2161(08)60996-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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33
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Uster PS. In situ resonance energy transfer microscopy: monitoring membrane fusion in living cells. Methods Enzymol 1993; 221:239-46. [PMID: 8361378 DOI: 10.1016/0076-6879(93)21021-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- P S Uster
- Liposome Technology, Inc., Menlo Park, California 94025
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34
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Affiliation(s)
- D Hoekstra
- Laboratory of Physiological Chemistry, University of Groningen, The Netherlands
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35
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Boiron F, Spivack WD, Deshmukh DS, Gould RM. Basis for phospholipid incorporation into peripheral nerve myelin. J Neurochem 1993; 60:320-9. [PMID: 8417153 DOI: 10.1111/j.1471-4159.1993.tb05854.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To characterize the mechanism(s) for targeting of phospholipids to peripheral nerve myelin, we examined the kinetics of incorporation of tritiated choline-, glycerol-, and ethanolamine-labeled phospholipids into four subfractions: microsomes, mitochondria, myelin-like material, and purified myelin at 1, 6, and 24 h after precursors were injected into sciatic nerves of 23-24-day-old rats. As validation of the fractionation scheme, a lag (> 1 h) in the accumulation of labeled phospholipids in the myelin-containing subfractions was found. This lag signifies the time between synthesis on organelles in Schwann cell cytoplasm and transport to myelin. In the present study, we find that sphingomyelin (choline-labeled) accumulated in myelin-rich subfractions only at 6 and 24 h, whereas phosphatidylserine (glycerol-labeled) and plasmalogen (ethanolamine-labeled) accumulated in the myelin-rich fractions by 1 h. The later phospholipids accumulate preferentially in the myelin-like fraction. These results are consistent with the notion that the targeting of sphingomyelin, a lipid present in the outer myelin leaflet, is different from the targeting of phosphatidylserine and ethanolamine plasmalogen, lipids in the inner leaflet. These findings are discussed in light of the possibility that sphingomyelin targeting is Golgi apparatus based, whereas phosphatidylserine and ethanolamine plasmalogen use a more direct transport system. Furthermore, the routes of phospholipid targeting mimic routes taken by myelin proteins P0 (Golgi) and myelin basic proteins (more direct).
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Affiliation(s)
- F Boiron
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314
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36
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Kagiwada S, Murata M, Hishida R, Tagaya M, Yamashina S, Ohnishi S. In vitro fusion of rabbit liver Golgi membranes with liposomes. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54093-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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37
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Kobayashi T, Storrie B, Simons K, Dotti CG. A functional barrier to movement of lipids in polarized neurons. Nature 1992; 359:647-50. [PMID: 1406997 DOI: 10.1038/359647a0] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In polarized neurons, axons and dendrites perform different functions, which are reflected in their different molecular organization. Studies on the sorting of viral and endogenous glycoproteins in epithelial cells and hippocampal neurons suggest that there may be similarities in the mechanism of sorting in these two cell types. The mechanisms that maintain the distinct composition of the two plasma membrane domains in these two cell types must, however, be different. We have proposed the existence of a functional barrier at the axonal hillock/initial segment which prevents the intermixing of membrane constituents. Here we test this hypothesis by fusing liposomes containing fluorescent phospholipids into the plasma membrane of polarized hippocampal cells in culture. Fusion was induced by lowering the pH and mediated by influenza virus haemagglutinin expressed on the axonal surface of neurons infected with fowl plague virus. Labelling was found exclusively on axons after fusion. Although the fused lipids were mobile on the axonal membrane, no labelling was detected on the cell body and dendritic surfaces. These results suggest that there is a diffusion barrier at the axonal hillock/initial segment which maintains the compositional differences between the axonal and somatodendritic domains.
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Affiliation(s)
- T Kobayashi
- Cell Biology Program, European Molecular Biology Laboratory, Heidelberg, Germany
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Moreau P, Juguelin H, Cassagne C, Morré DJ. Molecular basis for low temperature compartment formation by transitional endoplasmic reticulum of rat liver. FEBS Lett 1992; 310:223-8. [PMID: 1397277 DOI: 10.1016/0014-5793(92)81337-l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The molecular basis for temperature compartment formation was investigated using a cell-free system from rat liver. The donor was from liver slices prelabeled with [3H]acetate. Unlabeled Golgi apparatus membranes were immobilized on nitrocellulose as the acceptor. When transfer was determined as a function of temperature, a transition in transfer activity was observed at low temperatures (less than or equal to 20 degrees C) similar to that seen in vivo. The decrease in transfer efficiency correlated with a decrease in phosphatidylethanolamine and phosphatidylserine content of the transition vesicles formed. By adding lipid mixtures enriched in these lipids to the vesicles, their ability to fuse with the cis Golgi apparatus was reconstituted. These findings provide evidence for a role for lipids in low temperature compartment formation.
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Affiliation(s)
- P Moreau
- Centre National de la Recherche Scientifique, Institute de Biochimie Cellulaire et de Neurochimie, Bordeaux, France
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Kobayashi T, Arakawa Y. Transport of exogenous fluorescent phosphatidylserine analogue to the Golgi apparatus in cultured fibroblasts. J Cell Biol 1991; 113:235-44. [PMID: 2010461 PMCID: PMC2288936 DOI: 10.1083/jcb.113.2.235] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have examined intracellular transport and metabolism of the fluorescent analogue of phosphatidylserine, 1-palmitoyl-2-(N-[12[(7-nitrobenz-2-oxa-1,3-diazole-4-yl)amino] dodecanoyl])-phosphatidylserine ([palmitoyl-C12-NBD]-PS) in cultured fibroblasts. When monolayer cultures were incubated with liposomes containing (palmitoyl-C12-NBD)-PS at 37 degrees C, fluorescent PS was transported to the Golgi apparatus. NBD-containing analogues of phosphatidylcholine, phosphatidylethanolamine (PE), or phosphatidic acid did not accumulate in the Golgi apparatus under the same experimental conditions. We suggest that the transport is not due to endocytosis, but is the result of incorporation and trans-bilayer movement of the (palmitoyl-C12-NBD)-PS at the plasma membrane followed by translocation of the lipid from plasma membrane to the Golgi apparatus via nonvesicular mechanisms. Uptake of fluorescent PS was inhibited by depletion of cellular ATP and was blocked by structural analogues of the lipid or by pretreatment of cells with glutaraldehyde or N-ethylmaleimide. After incorporation into the cell, fluorescent PS was metabolized to fluorescent PE. The intracellular distribution of fluorescence changed during the conversion. In addition to the Golgi apparatus, mitochondria also became labeled.
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Affiliation(s)
- T Kobayashi
- Department of Hygiene and Preventive Medicine, School of Food and Nutritional Sciences, University of Shizuoka, Japan
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Donaldson JG, Lippincott-Schwartz J, Klausner RD. Guanine nucleotides modulate the effects of brefeldin A in semipermeable cells: regulation of the association of a 110-kD peripheral membrane protein with the Golgi apparatus. J Cell Biol 1991; 112:579-88. [PMID: 1993732 PMCID: PMC2288845 DOI: 10.1083/jcb.112.4.579] [Citation(s) in RCA: 159] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The release of a 110-kD peripheral membrane protein from the Golgi apparatus is an early event in brefeldin A (BFA) action, preceding the movement of Golgi membrane into the ER. ATP depletion also causes the reversible redistribution of the 110-kD protein from Golgi membrane into the cytosol, although no Golgi disassembly occurs. To further define the effects of BFA on the association of the 110-kD protein with the Golgi apparatus we have used filter perforation techniques to produce semipermeable cells. All previously observed effects of BFA, including the rapid redistribution of the 110-kD protein and the movement of Golgi membrane into the ER, could be reproduced in the semipermeable cells. The role of guanine nucleotides in this process was investigated using the nonhydrolyzable analogue of GTP, GTP gamma S. Pretreatment of semipermeable cells with GTP gamma S prevented the BFA-induced redistribution of the 110-kD protein from the Golgi apparatus and movement of Golgi membrane into the ER. GTP gamma S could also abrogate the observed release of the 110-kD protein from Golgi membranes which occurred in response to ATP depletion. Additionally, when the 110-kD protein had first been dissociated from Golgi membranes by ATP depletion, GTP gamma S could restore Golgi membrane association of the 110-kD protein, but not if BFA was present. All of these effects observed with GTP gamma S in semipermeable cells could be reproduced in intact cells treated with AlF4-. These results suggest that guanine nucleotides regulate the dynamic association/dissociation of the 110-kD protein with the Golgi apparatus and that BFA perturbs this process by interfering with the association of the 110-kD protein with the Golgi apparatus.
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Affiliation(s)
- J G Donaldson
- Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
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Wattenberg BW. Analysis of protein transport through the Golgi in a reconstituted cell-free system. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 1991; 17:150-64. [PMID: 1901603 DOI: 10.1002/jemt.1060170204] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The processes which transport membrane proteins between compartments of the Golgi apparatus have been reconstituted in vitro using isolated Golgi fractions. This cell-free system allows a detailed analysis of protein transport not possible in intact cells. Transport of the membrane glycoprotein (G protein) of vesicular stomatitis virus (VSV) is measured from a "donor" to an "acceptor" Golgi fraction. The donor Golgi fraction is prepared from VSV-infected Chinese hamster ovary (CHO) mutant cells deficient in the glycosylation enzyme N-acetylglucosamine transferase I. "Acceptor" is prepared from uninfected wild-type CHO cells. Transport is measured by the addition of N-acetylglucosamine to G protein, which can occur only upon movement of G protein from donor to acceptor. Transport requires physiological pH and osmolarity, is dependent on nucleotide triphosphates, and is mediated by proteins both from cytosol and on the Golgi membranes. Protein movement is inhibited by the non-hydrolyzable GTP analogue, GTP gamma S. The process of transport proceeds through the budding, pinching off, targeting, and fusion of transport vesicles. In this system these vesicles are initially coated with a non-clathrin coat and are targeted with this coat intact. Several of the proteins which mediate transport have been characterized, and isolated to homogeneity. The successful development of this assay has led to the formulation of cell free assays for protein transport between other compartments. Comparison of these systems indicates that some common mechanisms of vesicular movement are used in transport between a variety of membrane compartments.
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Straka MS, Junker LH, Zacarro L, Zogg DL, Dueland S, Everson GT, Davis RA. Substrate stimulation of 7 alpha-hydroxylase, an enzyme located in the cholesterol-poor endoplasmic reticulum. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39091-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Chattopadhyay A. Chemistry and biology of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-labeled lipids: fluorescent probes of biological and model membranes. Chem Phys Lipids 1990; 53:1-15. [PMID: 2191793 DOI: 10.1016/0009-3084(90)90128-e] [Citation(s) in RCA: 280] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Lipids that are covalently labeled with the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group are widely used as fluorescent analogues of native lipids in model and biological membranes to study a variety of processes. The fluorescent NBD group may be attached either to the polar or the apolar regions of a wide variety of lipid molecules. Synthetic routes for preparing the lipids, and spectroscopic and ionization properties of these probes are reviewed in this report. The orientation of various NBD-labeled lipids in membranes, as indicated by the location of the NBD group, is also discussed. The NBD group is uncharged at neutral pH in membranes, but loops up to the surface if attached to acyl chains of phospholipids. These lipids find applications in a variety of membrane-related studies which include membrane fusion, lipid motion and dynamics, organization of lipids and proteins in membranes, intracellular lipid transfer, and bilayer to hexagonal phase transition in liposomes. Use of NBD-labeled lipids as analogues of natural lipids is critically evaluated.
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Affiliation(s)
- A Chattopadhyay
- Department of Biochemistry and Biophysics, University of California, Davis 95616
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Abstract
To study the construction of the ER, we used the microtubule-disrupting drug nocodazole to induce the complete breakdown of ER structure in living cells followed by recovery in drug-free medium, which regenerates the ER network within 15 min. Using the fluorescent dye 3,3'-dihexyloxacarbocyanine iodide to visualize the ER, we have directly observed the network construction process in living cells. In these experiments, the ER network was constructed through an iterative process of extension, branching, and intersection of new ER tubules driven by the ER motility previously described as tubule branching. We have tested the cytoskeletal requirements of this process. We find that newly formed ER tubules are aligned with single microtubules but not actin fibers or vimentin intermediate filaments. Microtubule polymerization preceded the extension of ER tubules and, in experiments with a variety of different drugs, appeared to be a necessary condition for the ER network formation. Furthermore, perturbations of the pattern of microtubule polymerization with microtubule-specific drugs caused exactly correlated perturbations of the pattern of ER construction. Induction of abnormally short, nonintersecting microtubules with 20 microM taxol prevented the ER network formation; ER tubules only extended along the few microtubules contacting the aggregated ER membranes. This requirement for a continuous network of intersecting microtubules indicates that ER network formation takes place through the branching and movement of ER membranes along microtubules. Cytochalasin B had no apparent effect on the construction of the ER network during recovery, despite apparently complete disruption of actin fibers as stained by phalloidin. Blockage of protein synthesis and disorganization of intermediate filaments with cycloheximide pretreatment also failed to perturb ER construction.
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Affiliation(s)
- C Lee
- Division of Cellular and Molecular Biology, Dana-Farber Cancer Institute, Boston, Massachusetts
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Affiliation(s)
- J Wilschut
- Laboratory of Physiological Chemistry, University of Groningen, The Netherlands
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