1
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Kulma M, Šakanović A, Bedina-Zavec A, Caserman S, Omersa N, Šolinc G, Orehek S, Hafner-Bratkovič I, Kuhar U, Slavec B, Krapež U, Ocepek M, Kobayashi T, Kwiatkowska K, Jerala R, Podobnik M, Anderluh G. Sequestration of membrane cholesterol by cholesterol-binding proteins inhibits SARS-CoV-2 entry into Vero E6 cells. Biochem Biophys Res Commun 2024; 716:149954. [PMID: 38704887 DOI: 10.1016/j.bbrc.2024.149954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 03/26/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024]
Abstract
Membrane lipids and proteins form dynamic domains crucial for physiological and pathophysiological processes, including viral infection. Many plasma membrane proteins, residing within membrane domains enriched with cholesterol (CHOL) and sphingomyelin (SM), serve as receptors for attachment and entry of viruses into the host cell. Among these, human coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), use proteins associated with membrane domains for initial binding and internalization. We hypothesized that the interaction of lipid-binding proteins with CHOL in plasma membrane could sequestrate lipids and thus affect the efficiency of virus entry into host cells, preventing the initial steps of viral infection. We have prepared CHOL-binding proteins with high affinities for lipids in the plasma membrane of mammalian cells. Binding of the perfringolysin O domain four (D4) and its variant D4E458L to membrane CHOL impaired the internalization of the receptor-binding domain of the SARS-CoV-2 spike protein and the pseudovirus complemented with the SARS-CoV-2 spike protein. SARS-CoV-2 replication in Vero E6 cells was also decreased. Overall, our results demonstrate that the integrity of CHOL-rich membrane domains and the accessibility of CHOL in the membrane play an essential role in SARS-CoV-2 cell entry.
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Affiliation(s)
- Magdalena Kulma
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Aleksandra Šakanović
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Apolonija Bedina-Zavec
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Simon Caserman
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Neža Omersa
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Gašper Šolinc
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Sara Orehek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Iva Hafner-Bratkovič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne Fronte 13, 1000, Ljubljana, Slovenia
| | - Urška Kuhar
- Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000, Ljubljana, Slovenia
| | - Brigita Slavec
- Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000, Ljubljana, Slovenia
| | - Uroš Krapež
- Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000, Ljubljana, Slovenia
| | - Matjaž Ocepek
- Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000, Ljubljana, Slovenia
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan; UMR 7021 CNRS, Université de Strasbourg, F-67401, Illkirch, France
| | - Katarzyna Kwiatkowska
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, 3 Pasteur St., 02-093, Warsaw, Poland
| | - Roman Jerala
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne Fronte 13, 1000, Ljubljana, Slovenia
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia.
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2
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Tomishige N, Bin Nasim M, Murate M, Pollet B, Didier P, Godet J, Richert L, Sako Y, Mély Y, Kobayashi T. HIV-1 Gag targeting to the plasma membrane reorganizes sphingomyelin-rich and cholesterol-rich lipid domains. Nat Commun 2023; 14:7353. [PMID: 37990014 PMCID: PMC10663554 DOI: 10.1038/s41467-023-42994-w] [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: 08/30/2021] [Accepted: 10/26/2023] [Indexed: 11/23/2023] Open
Abstract
Although the human immunodeficiency virus type 1 lipid envelope has been reported to be enriched with host cell sphingomyelin and cholesterol, the molecular mechanism of the enrichment is not well understood. Viral Gag protein plays a central role in virus budding. Here, we report the interaction between Gag and host cell lipids using different quantitative and super-resolution microscopy techniques in combination with specific probes that bind endogenous sphingomyelin and cholesterol. Our results indicate that Gag in the inner leaflet of the plasma membrane colocalizes with the outer leaflet sphingomyelin-rich domains and cholesterol-rich domains, enlarges sphingomyelin-rich domains, and strongly restricts the mobility of sphingomyelin-rich domains. Moreover, Gag multimerization induces sphingomyelin-rich and cholesterol-rich lipid domains to be in close proximity in a curvature-dependent manner. Our study suggests that Gag binds, coalesces, and reorganizes pre-existing lipid domains during assembly.
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Affiliation(s)
- Nario Tomishige
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, Japan.
| | - Maaz Bin Nasim
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
- Faculty of Pharmacy, The University of Lahore, Lahore, Pakistan
| | - Motohide Murate
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, Japan
| | - Brigitte Pollet
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
| | - Pascal Didier
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
| | - Julien Godet
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
| | - Ludovic Richert
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, Japan
| | - Yves Mély
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France.
| | - Toshihide Kobayashi
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, Japan.
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3
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Honda A, Nozumi M, Ito Y, Natsume R, Kawasaki A, Nakatsu F, Abe M, Uchino H, Matsushita N, Ikeda K, Arita M, Sakimura K, Igarashi M. Very-long-chain fatty acids are crucial to neuronal polarity by providing sphingolipids to lipid rafts. Cell Rep 2023; 42:113195. [PMID: 37816355 DOI: 10.1016/j.celrep.2023.113195] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/19/2023] [Accepted: 09/14/2023] [Indexed: 10/12/2023] Open
Abstract
Fatty acids have long been considered essential to brain development; however, the involvement of their synthesis in nervous system formation is unclear. We generate mice with knockout of GPSN2, an enzyme for synthesis of very-long-chain fatty acids (VLCFAs) and investigate the effects. Both GPSN2-/- and GPSN2+/- mice show abnormal neuronal networks as a result of impaired neuronal polarity determination. Lipidomics of GPSN2-/- embryos reveal that ceramide synthesis is specifically inhibited depending on FA length; namely, VLCFA-containing ceramide is reduced. We demonstrate that lipid rafts are highly enriched in growth cones and that GPSN2+/- neurons lose gangliosides in their membranes. Application of C24:0 ceramide, but not C16:0 ceramide or C24:0 phosphatidylcholine, to GPSN2+/- neurons rescues both neuronal polarity determination and lipid-raft density in the growth cone. Taken together, our results indicate that VLCFA synthesis contributes to physiological neuronal development in brain network formation, in particular neuronal polarity determination through the formation of lipid rafts.
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Affiliation(s)
- Atsuko Honda
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan; Center for Research Promotion, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan
| | - Motohiro Nozumi
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan
| | - Yasuyuki Ito
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan
| | - Rie Natsume
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan; Department of Animal Model Development, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan
| | - Asami Kawasaki
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan
| | - Fubito Nakatsu
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan; Department of Animal Model Development, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan
| | - Haruki Uchino
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo 105-8512, Japan
| | - Natsuki Matsushita
- Division of Laboratory Animal Research, Aichi Medical University School of Medicine, Nagakute, Aichi 480-1195, Japan
| | - Kazutaka Ikeda
- Department of Applied Genomics, Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan
| | - Makoto Arita
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo 105-8512, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan; Department of Animal Model Development, Brain Research Institute, Niigata University, Chuo-ku, Niigata 951-8585, Japan
| | - Michihiro Igarashi
- Department of Neurochemistry and Molecular Cell Biology, School of Medicine and Graduate School of Medical/Dental Sciences, Niigata University, Chuo-ku, Niigata 951-8510, Japan.
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4
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Lv X, Jin K, Yi Y, Song L, Xiu X, Liu Y, Li J, Du G, Chen J, Liu L. Analysis of acid-tolerance mechanism based on membrane microdomains in Saccharomyces cerevisiae. Microb Cell Fact 2023; 22:180. [PMID: 37700284 PMCID: PMC10498586 DOI: 10.1186/s12934-023-02195-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 09/05/2023] [Indexed: 09/14/2023] Open
Abstract
BACKGROUND Saccharomyces cerevisiae has been used in the biosynthesis of acid products such as organic acids owing to its acid tolerance. Improving the acid tolerance of S. cerevisiae is beneficial for expanding its application range. Our previous study isolated the TAMC strain that was tolerant to a pH 2.3 through adaptive laboratory evolution; however, its mechanism underlying tolerance to low pH environment remains unclear. RESULTS In this study, through visual observation and order analysis of plasma membrane and membrane microdomains, we revealed that the membrane microdomains of TAMC strain play an indispensable role in acid tolerance. Transcriptomic analysis showed an increase in the expression of genes related to key components of membrane microdomains in TAMC strain. Furthermore, an obvious reduction was observed in the acid tolerance of the strain with sterol C-24 methyltransferase encoding gene ERG6 knockout for inhibiting membrane microdomain formation. Finally, colocalization analysis of H+-ATPase PMA1 and plasma membrane protein PMP1 showed that disruption of membrane microdomains could inhibit the formation of the H+-ATPase complex. CONCLUSIONS Membrane microdomains could provide a platform for forming H+-ATPase complexes to facilitate intracellular H+ homeostasis, and thereby improve cell acid resistance. This study proposed a novel acid tolerance mechanism, providing a new direction for the rational engineering of acid-tolerant strains.
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Affiliation(s)
- Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
- Yixing Institute of Food Biotechnology Co., Ltd, Yixing, 214200, China
| | - Ke Jin
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
- Yixing Institute of Food Biotechnology Co., Ltd, Yixing, 214200, China
| | - Yu Yi
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Lingang Song
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Xiang Xiu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jian Chen
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
- Yixing Institute of Food Biotechnology Co., Ltd, Yixing, 214200, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China.
- Yixing Institute of Food Biotechnology Co., Ltd, Yixing, 214200, China.
- Food Laboratory of Zhongyuan, Jiangnan University, Wuxi, 214122, China.
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5
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Lange Y, Tabei SMA, Steck TL. A basic model for the association of ligands with membrane cholesterol: application to cytolysin binding. J Lipid Res 2023; 64:100344. [PMID: 36791915 PMCID: PMC10119614 DOI: 10.1016/j.jlr.2023.100344] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/19/2023] [Accepted: 02/07/2023] [Indexed: 02/16/2023] Open
Abstract
Almost all the cholesterol in cellular membranes is associated with phospholipids in simple stoichiometric complexes. This limits the binding of sterol ligands such as filipin and Perfringolysin O (PFO) to a small fraction of the total. We offer a simple mathematical model that characterizes this complexity. It posits that the cholesterol accessible to ligands has two forms: active cholesterol, which is that not complexed with phospholipids; and extractable cholesterol, that which ligands can capture competitively from the phospholipid complexes. Simulations based on the model match published data for the association of PFO oligomers with liposomes, plasma membranes and the isolated endoplasmic reticulum. The model shows how the binding of a probe greatly underestimates cholesterol abundance when its affinity for the sterol is so weak that it competes poorly with the membrane phospholipids. Two examples are the under-staining of plasma membranes by filipin and the failure of domain D4 of PFO to label their cytoplasmic leaflets. Conversely, the exaggerated staining of endolysosomes suggests that their cholesterol, being uncomplexed, is readily available. The model is also applicable to the association of cholesterol with intrinsic membrane proteins. For example, it supports the hypothesis that the sharp threshold in the regulation of homeostatic ER proteins by cholesterol derives from the cooperativity of their binding to the sterol weakly held by the phospholipid. § Thus, the model explicates the complexity inherent in the binding of ligands like PFO and filipin to the small accessible fraction of membrane cholesterol.
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Affiliation(s)
- Yvonne Lange
- 1Department of Pathology, Rush University Medical Center, Chicago, Il 60612, USA.
| | - S M Ali Tabei
- Department of Physics, University of Northern Iowa, Cedar Falls, Iowa 50614, USA
| | - Theodore L Steck
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Il 60637, USA
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6
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Yamaji-Hasegawa A, Murate M, Inaba T, Dohmae N, Sato M, Fujimori F, Sako Y, Greimel P, Kobayashi T. A novel sterol-binding protein reveals heterogeneous cholesterol distribution in neurite outgrowth and in late endosomes/lysosomes. Cell Mol Life Sci 2022; 79:324. [PMID: 35644822 PMCID: PMC11072113 DOI: 10.1007/s00018-022-04339-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 11/24/2022]
Abstract
We identified a mushroom-derived protein, maistero-2 that specifically binds 3-hydroxy sterol including cholesterol (Chol). Maistero-2 bound lipid mixture in Chol-dependent manner with a binding threshold of around 30%. Changing lipid composition did not significantly affect the threshold concentration. EGFP-maistero-2 labeled cell surface and intracellular organelle Chol with higher sensitivity than that of well-established Chol probe, D4 fragment of perfringolysin O. EGFP-maistero-2 revealed increase of cell surface Chol during neurite outgrowth and heterogeneous Chol distribution between CD63-positive and LAMP1-positive late endosomes/lysosomes. The absence of strictly conserved Thr-Leu pair present in Chol-dependent cytolysins suggests a distinct Chol-binding mechanism for maistero-2.
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Affiliation(s)
| | - Motohide Murate
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
- Cellular Informatics Laboratory, RIKEN CPR, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
- UMR 7021, CNRS, Université de Strasbourg, 67401, Illkirch, France
| | - Takehiko Inaba
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
- Cellular Informatics Laboratory, RIKEN CPR, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit, RIKEN CSRS, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan
| | - Masayuki Sato
- Yukiguni Maitake Co, Ltd. Yokawa 89, Minamiuonuma, Niigata, 949-6695, Japan
| | - Fumihiro Fujimori
- Laboratory of Biological Science and Technology, Tokyo Kasei University, 1-18-1 Kaga, Itabashi, Tokyo, 173-8062, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN CPR, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, 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.
- Cellular Informatics Laboratory, RIKEN CPR, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.
- UMR 7021, CNRS, Université de Strasbourg, 67401, Illkirch, France.
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7
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Awan S, Lambert M, Imtiaz A, Alpy F, Tomasetto C, Oulad-Abdelghani M, Schaeffer C, Moritz C, Julien-David D, Najib S, Martinez LO, Matz RL, Collet X, Silva-Rojas R, Böhm J, Herz J, Terrand J, Boucher P. Wnt5a Promotes Lysosomal Cholesterol Egress and Protects Against Atherosclerosis. Circ Res 2022; 130:184-199. [PMID: 34886684 PMCID: PMC8776607 DOI: 10.1161/circresaha.121.318881] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND Impairment of cellular cholesterol trafficking is at the heart of atherosclerotic lesions formation. This involves egress of cholesterol from the lysosomes and 2 lysosomal proteins, the NPC1 (Niemann-Pick C1) and NPC2 that promotes cholesterol trafficking. However, movement of cholesterol out the lysosome and how disrupted cholesterol trafficking leads to atherosclerosis is unclear. As the Wnt ligand, Wnt5a inhibits the intracellular accumulation of cholesterol in multiple cell types, we tested whether Wnt5a interacts with the lysosomal cholesterol export machinery and studied its role in atherosclerotic lesions formation. METHODS We generated mice deleted for the Wnt5a gene in vascular smooth muscle cells. To establish whether Wnt5a also protects against cholesterol accumulation in human vascular smooth muscle cells, we used a CRISPR/Cas9 guided nuclease approach to generate human vascular smooth muscle cells knockout for Wnt5a. RESULTS We show that Wnt5a is a crucial component of the lysosomal cholesterol export machinery. By increasing lysosomal acid lipase expression, decreasing metabolic signaling by the mTORC1 (mechanistic target of rapamycin complex 1) kinase, and through binding to NPC1 and NPC2, Wnt5a senses changes in dietary cholesterol supply and promotes lysosomal cholesterol egress to the endoplasmic reticulum. Consequently, loss of Wnt5a decoupled mTORC1 from variations in lysosomal sterol levels, disrupted lysosomal function, decreased cholesterol content in the endoplasmic reticulum, and promoted atherosclerosis. CONCLUSIONS These results reveal an unexpected function of the Wnt5a pathway as essential for maintaining cholesterol homeostasis in vivo.
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Affiliation(s)
- Sara Awan
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
| | - Magalie Lambert
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
| | - Ali Imtiaz
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
| | - Fabien Alpy
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), University of Strasbourg, 1 Rue Laurent Fries, 67400 Illkirch-Graffenstaden, France
| | - Catherine Tomasetto
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), University of Strasbourg, 1 Rue Laurent Fries, 67400 Illkirch-Graffenstaden, France
| | - Mustapha Oulad-Abdelghani
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), University of Strasbourg, 1 Rue Laurent Fries, 67400 Illkirch-Graffenstaden, France
| | - Christine Schaeffer
- Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, 23 Rue du Loess, 67037 Strasbourg, France
| | - Chloé Moritz
- Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, 23 Rue du Loess, 67037 Strasbourg, France
| | - Diane Julien-David
- CNRS, UMR 7178, University of Strasbourg, 23 Rue du Loess, 67037 Strasbourg, France
| | - Souad Najib
- Institute of Metabolic and Cardiovascular Diseases, I2MC, INSERM, UMR, 1048, 1 avenue du Professeur Jean Poulhès, 31432 Toulouse, France
| | - Laurent O. Martinez
- Institute of Metabolic and Cardiovascular Diseases, I2MC, INSERM, UMR, 1048, 1 avenue du Professeur Jean Poulhès, 31432 Toulouse, France
| | - Rachel L. Matz
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
| | - Xavier Collet
- Institute of Metabolic and Cardiovascular Diseases, I2MC, INSERM, UMR, 1048, 1 avenue du Professeur Jean Poulhès, 31432 Toulouse, France
| | - Roberto Silva-Rojas
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), University of Strasbourg, 1 Rue Laurent Fries, 67400 Illkirch-Graffenstaden, France
| | - Johann Böhm
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), University of Strasbourg, 1 Rue Laurent Fries, 67400 Illkirch-Graffenstaden, France
| | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, Texas 75390, USA
| | - Jérôme Terrand
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
| | - Philippe Boucher
- UMR-S INSERM 1109, University of Strasbourg, 1, place de l’Hôpital, 67000 Strasbourg, France
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8
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Miyamoto T, Hosoba K, Akutsu SN, Matsuura S. Imaging of the Ciliary Cholesterol Underlying the Sonic Hedgehog Signal Transduction. Methods Mol Biol 2022; 2374:49-57. [PMID: 34562242 DOI: 10.1007/978-1-0716-1701-4_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Primary cilia are antenna-like structures that develop on the surface of quiescent G0-phase cells and receive extracellular signals including sonic hedgehog (Shh) for embryogenesis and adult tissue homeostasis. In mammalian cells, cholesterol activates the seven-transmembrane protein Smoothened to transduce the Shh signal. Germline mutations of the DHCR7 gene encoding the cholesterol biogenesis enzyme 7-dehydrocholesterol reductase cause Smith-Lemli-Opitz syndrome with ciliopathy-related symptoms such as polycystic kidney and polydactyly, implying that cholesterol is indeed involved in ciliary functions. Notably, it has been reported that the cholesterol in ciliary membranes is significantly more abundant than that in the rest of the plasma membrane. However, several studies have failed to image the enriched ciliary cholesterol. Here, we propose a set of protocols for the sensitive imaging of ciliary cholesterol using the fluorescent small compound Filipin III and the green fluorescent protein tagged Domain 4 of the exotoxin Perfringolysin O derived from the anaerobic bacterium Clostridium perfringens. These cholesterol probes should be powerful tools for understanding the physiological and pathological roles of ciliary cholesterol in the context of Shh signaling in mammalian cells.
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Affiliation(s)
- Tatsuo Miyamoto
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.
| | - Kosuke Hosoba
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Silvia Natsuko Akutsu
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Shinya Matsuura
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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9
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Kinnebrew M, Johnson KA, Radhakrishnan A, Rohatgi R. Measuring and Manipulating Membrane Cholesterol for the Study of Hedgehog Signaling. Methods Mol Biol 2022; 2374:73-87. [PMID: 34562244 PMCID: PMC8819901 DOI: 10.1007/978-1-0716-1701-4_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cholesterol is an abundant lipid in mammalian plasma membranes that regulates the reception of the Hedgehog (Hh) signal in target cells. In vertebrates, cell-surface organelles called primary cilia function as compartments for the propagation of Hh signals. Recent structural, biochemical, and cell-biological studies have led to the model that Patched-1 (PTCH1), the receptor for Hh ligands, uses its transporter-like activity to lower cholesterol accessibility in the membrane surrounding primary cilia. Cholesterol restriction at cilia may represent the long-sought-after mechanism by which PTCH1 inhibits Smoothened (SMO), a cholesterol-responsive transmembrane protein of the G protein-coupled receptor superfamily that transmits the Hh signal across the membrane.Protein probes based on microbial cholesterol-binding proteins revealed that PTCH1 controls only a subset of the total cholesterol molecules, a biochemically defined fraction called accessible cholesterol. The accessible cholesterol pool coexists (and exchanges) with a pool of sequestered cholesterol, which is bound to phospholipids like sphingomyelin. In this chapter, we describe how to measure the accessible and sequestered cholesterol pools in live cells with protein-based probes. We discuss how to purify and fluorescently label these probes for use in flow cytometry and microscopy-based measurements of the cholesterol pools. Additionally, we describe how to modulate accessible cholesterol levels to determine if this pool regulates Hh signaling (or any other cellular process of interest).
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Affiliation(s)
- Maia Kinnebrew
- Department of Medicine and Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - Kristen A Johnson
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Arun Radhakrishnan
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Rajat Rohatgi
- Department of Medicine and Biochemistry, Stanford University School of Medicine, Stanford, CA, USA.
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10
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Barrantes FJ. Fluorescence sensors for imaging membrane lipid domains and cholesterol. CURRENT TOPICS IN MEMBRANES 2021; 88:257-314. [PMID: 34862029 DOI: 10.1016/bs.ctm.2021.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Lipid membrane domains are supramolecular lateral heterogeneities of biological membranes. Of nanoscopic dimensions, they constitute specialized hubs used by the cell as transient signaling platforms for a great variety of biologically important mechanisms. Their property to form and dissolve in the bulk lipid bilayer endow them with the ability to engage in highly dynamic processes, and temporarily recruit subpopulations of membrane proteins in reduced nanometric compartments that can coalesce to form larger mesoscale assemblies. Cholesterol is an essential component of these lipid domains; its unique molecular structure is suitable for interacting intricately with crevices and cavities of transmembrane protein surfaces through its rough β face while "talking" to fatty acid acyl chains of glycerophospholipids and sphingolipids via its smooth α face. Progress in the field of membrane domains has been closely associated with innovative improvements in fluorescence microscopy and new fluorescence sensors. These advances enabled the exploration of the biophysical properties of lipids and their supramolecular platforms. Here I review the rationale behind the use of biosensors over the last few decades and their contributions towards elucidation of the in-plane and transbilayer topography of cholesterol-enriched lipid domains and their molecular constituents. The challenges introduced by super-resolution optical microscopy are discussed, as well as possible scenarios for future developments in the field, including virtual ("no staining") staining.
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Affiliation(s)
- Francisco J Barrantes
- Biomedical Research Institute (BIOMED), Catholic University of Argentina (UCA)-National Scientific and Technical Research Council (CONICET), Buenos Aires, Argentina.
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11
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Schoop V, Martello A, Eden ER, Höglinger D. Cellular cholesterol and how to find it. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158989. [PMID: 34118431 DOI: 10.1016/j.bbalip.2021.158989] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 01/06/2023]
Abstract
Cholesterol is an essential component of eukaryotic cellular membranes. Information about its subcellular localization and transport pathways inside cells are key for the understanding and treatment of cholesterol-related diseases. In this review we give an overview over the most commonly used methods that contributed to our current understanding of subcellular cholesterol localization and transport routes. First, we discuss methods that provide insights into cholesterol metabolism based on readouts of downstream effects such as esterification. Subsequently, we focus on the use of cholesterol-binding molecules as probes that facilitate visualization and quantification of sterols inside of cells. Finally, we explore different analogues of cholesterol which, when taken up by living cells, are integrated and transported in a similar fashion as endogenous sterols. Taken together, we highlight the challenges and advantages of each method such that researchers studying aspects of cholesterol transport may choose the most pertinent approach for their problem.
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Affiliation(s)
- Valentin Schoop
- Heidelberg University Biochemistry Center (BZH), 69120 Heidelberg, Germany
| | - Andrea Martello
- University College London (UCL), Institute of Ophthalmology, EC1V 9EL London, United Kingdom
| | - Emily R Eden
- University College London (UCL), Institute of Ophthalmology, EC1V 9EL London, United Kingdom
| | - Doris Höglinger
- Heidelberg University Biochemistry Center (BZH), 69120 Heidelberg, Germany.
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12
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What Can Mushroom Proteins Teach Us about Lipid Rafts? MEMBRANES 2021; 11:membranes11040264. [PMID: 33917311 PMCID: PMC8067419 DOI: 10.3390/membranes11040264] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/31/2021] [Accepted: 03/31/2021] [Indexed: 12/25/2022]
Abstract
The lipid raft hypothesis emerged as a need to explain the lateral organization and behavior of lipids in the environment of biological membranes. The idea, that lipids segregate in biological membranes to form liquid-disordered and liquid-ordered states, was faced with a challenge: to show that lipid-ordered domains, enriched in sphingomyelin and cholesterol, actually exist in vivo. A great deal of indirect evidence and the use of lipid-binding probes supported this idea, but there was a lack of tools to demonstrate the existence of such domains in living cells. A whole new toolbox had to be invented to biochemically characterize lipid rafts and to define how they are involved in several cellular functions. A potential solution came from basic biochemical experiments in the late 1970s, showing that some mushroom extracts exert hemolytic activities. These activities were later assigned to aegerolysin-based sphingomyelin/cholesterol-specific cytolytic protein complexes. Recently, six sphingomyelin/cholesterol binding proteins from different mushrooms have been identified and have provided some insight into the nature of sphingomyelin/cholesterol-rich domains in living vertebrate cells. In this review, we dissect the accumulated knowledge and introduce the mushroom lipid raft binding proteins as molecules of choice to study the dynamics and origins of these liquid-ordered domains in mammalian cells.
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13
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Tomishige N, Murate M, Didier P, Richert L, Mély Y, Kobayashi T. The use of pore-forming toxins to image lipids and lipid domains. Methods Enzymol 2021; 649:503-542. [PMID: 33712198 DOI: 10.1016/bs.mie.2021.01.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Very few proteins are reported to bind specific lipids. Because of the high selectivity and strong binding to specific lipids, lipid-targeting pore forming toxins (PFTs) have been employed to study the distribution of lipids in cell- and model-membranes. Non-toxic and monomeric PFT-derivatives are especially useful to study living cells. In this chapter we highlight sphingomyelin (SM)-binding PFT, lysenin (Lys), its derivatives, and newly identified SM/cholesterol binding protein, nakanori. We describe the preparation of non-toxic mutant of Lys (NT-Lys) and its application in optical and super resolution microscopy. We also discuss the observation of nanometer scale lipid domains labeled with nakanori and maltose-binding protein (MBP)-Lys in electron microscopy.
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Affiliation(s)
| | | | - Pascal Didier
- UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
| | | | - Yves Mély
- UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
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14
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Drabavicius G, Daelemans D. Intermedilysin cytolytic activity depends on heparan sulfates and membrane composition. PLoS Genet 2021; 17:e1009387. [PMID: 33577603 PMCID: PMC7906465 DOI: 10.1371/journal.pgen.1009387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 02/25/2021] [Accepted: 01/27/2021] [Indexed: 12/26/2022] Open
Abstract
Cholesterol-dependent cytolysins (CDCs), of which intermedilysin (ILY) is an archetypal member, are a group of pore-forming toxins secreted by a large variety of pathogenic bacteria. These toxins, secreted as soluble monomers, oligomerize upon interaction with cholesterol in the target membrane and transect it as pores of diameters of up to 100 to 300 Å. These pores disrupt cell membranes and result in cell lysis. The immune receptor CD59 is a well-established cellular factor required for intermedilysin pore formation. In this study, we applied genome-wide CRISPR-Cas9 knock-out screening to reveal additional cellular co-factors essential for ILY-mediated cell lysis. We discovered a plethora of genes previously not associated with ILY, many of which are important for membrane constitution. We show that heparan sulfates facilitate ILY activity, which can be inhibited by heparin. Furthermore, we identified hits in both protein and lipid glycosylation pathways and show a role for glucosylceramide, demonstrating that membrane organization is important for ILY activity. We also cross-validated identified genes with vaginolysin and pneumolysin and found that pneumolysin's cytolytic activity strongly depends on the asymmetric distribution of membrane phospholipids. This study shows that membrane-targeting toxins combined with genetic screening can identify genes involved in biological membrane composition and metabolism.
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Affiliation(s)
- Gediminas Drabavicius
- KU Leuven Department of Microbiology, Immunology, and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven, Belgium
- Vilnius University, Life Sciences Center, Institute of Biotechnology, Vilnius, Lithuania
| | - Dirk Daelemans
- KU Leuven Department of Microbiology, Immunology, and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven, Belgium
- * E-mail:
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15
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Penkauskas T, Zentelyte A, Ganpule S, Valincius G, Preta G. Pleiotropic effects of statins via interaction with the lipid bilayer: A combined approach. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183306. [DOI: 10.1016/j.bbamem.2020.183306] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/18/2020] [Accepted: 04/07/2020] [Indexed: 12/25/2022]
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16
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Igarashi M, Honda A, Kawasaki A, Nozumi M. Neuronal Signaling Involved in Neuronal Polarization and Growth: Lipid Rafts and Phosphorylation. Front Mol Neurosci 2020; 13:150. [PMID: 32922262 PMCID: PMC7456915 DOI: 10.3389/fnmol.2020.00150] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 07/16/2020] [Indexed: 12/17/2022] Open
Abstract
Neuronal polarization and growth are developmental processes that occur during neuronal cell differentiation. The molecular signaling mechanisms involved in these events in in vivo mammalian brain remain unclear. Also, cellular events of the neuronal polarization process within a given neuron are thought to be constituted of many independent intracellular signal transduction pathways (the "tug-of-war" model). However, in vivo results suggest that such pathways should be cooperative with one another among a given group of neurons in a region of the brain. Lipid rafts, specific membrane domains with low fluidity, are candidates for the hotspots of such intracellular signaling. Among the signals reported to be involved in polarization, a number are thought to be present or translocated to the lipid rafts in response to extracellular signals. As part of our analysis, we discuss how such novel molecular mechanisms are combined for effective regulation of neuronal polarization and growth, focusing on the significance of the lipid rafts, including results based on recently introduced methods.
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Affiliation(s)
- Michihiro Igarashi
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Atsuko Honda
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Asami Kawasaki
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Motohiro Nozumi
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
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17
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Miyamoto T, Hosoba K, Itabashi T, Iwane AH, Akutsu SN, Ochiai H, Saito Y, Yamamoto T, Matsuura S. Insufficiency of ciliary cholesterol in hereditary Zellweger syndrome. EMBO J 2020; 39:e103499. [PMID: 32368833 PMCID: PMC7298307 DOI: 10.15252/embj.2019103499] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 03/13/2020] [Accepted: 03/20/2020] [Indexed: 11/22/2022] Open
Abstract
Primary cilia are antenna‐like organelles on the surface of most mammalian cells that receive sonic hedgehog (Shh) signaling in embryogenesis and carcinogenesis. Cellular cholesterol functions as a direct activator of a seven‐transmembrane oncoprotein called Smoothened (Smo) and thereby induces Smo accumulation on the ciliary membrane where it transduces the Shh signal. However, how cholesterol is supplied to the ciliary membrane remains unclear. Here, we report that peroxisomes are essential for the transport of cholesterol into the ciliary membrane. Zellweger syndrome (ZS) is a peroxisome‐deficient hereditary disorder with several ciliopathy‐related features and cells from these patients showed a reduced cholesterol level in the ciliary membrane. Reverse genetics approaches revealed that the GTP exchange factor Rabin8, the Rab GTPase Rab10, and the microtubule minus‐end‐directed kinesin KIFC3 form a peroxisome‐associated complex to control the movement of peroxisomes along microtubules, enabling communication between peroxisomes and ciliary pocket membranes. Our findings suggest that insufficient ciliary cholesterol levels may underlie ciliopathies.
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Affiliation(s)
- Tatsuo Miyamoto
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Kosuke Hosoba
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.,Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Takeshi Itabashi
- Laboratory for Cell Field Structure, RIKEN Center for Biosystems Dynamics Research, Higashi-Hiroshima, Japan
| | - Atsuko H Iwane
- Laboratory for Cell Field Structure, RIKEN Center for Biosystems Dynamics Research, Higashi-Hiroshima, Japan
| | - Silvia Natsuko Akutsu
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Hiroshi Ochiai
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Yumiko Saito
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan.,Program of Life and Environmental Sciences, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Takashi Yamamoto
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan.,Program of Mathematical and Life Sciences, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Shinya Matsuura
- Department of Genetics and Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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18
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Petrov AM, Mast N, Li Y, Denker J, Pikuleva IA. Brain sterol flux mediated by cytochrome P450 46A1 affects membrane properties and membrane-dependent processes. Brain Commun 2020; 2. [PMID: 32661514 PMCID: PMC7357967 DOI: 10.1093/braincomms/fcaa043] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cytochrome P450 46A1 encoded by CYP46A1 catalyzes cholesterol 24-hydroxylation and is a CNS-specific enzyme that controls cholesterol removal and turnover in the brain. Accumulating data suggest that increases in cytochrome P450 46A1 activity in mouse models of common neurodegenerative diseases affect various, apparently unlinked biological processes and pathways. Yet, the underlying reason for these multiple enzyme activity effects is currently unknown. Herein, we tested the hypothesis that cytochrome P450 46A1-mediated sterol flux alters physico-chemical properties of the plasma membranes and thereby membrane-dependent events. We used 9-month old 5XFAD mice (an Alzheimer's disease model) treated for 6 months with the anti-HIV drug efavirenz. These animals have previously been shown to have improved behavioral performance, increased cytochrome P450 46A1 activity in the brain, and increased sterol flux through the plasma membranes. We further examined 9-month old Cyp46a1 -/- mice, which have previously been observed to have cognitive deficits and decreased sterol flux through brain membranes. Synaptosomal fractions from the brain of efavirenz-treated 5XFAD mice had essentially unchanged cholesterol levels as compared to control 5XFAD mice. However with efavirenz treatment in these mice, there were changes in the membrane properties (increased cholesterol accessibility, ordering, osmotic resistance, and thickness) as well as total glutamate content and ability to release glutamate in response to mild stimulation. Similarly, the cholesterol content in synaptosomal fractions from the brain of Cyp46a1 -/- mice was essentially the same as in wild type mice but knockout of Cyp46a1 was associated with changes in membrane properties and glutamate content and its exocytotic release. Changes in Cyp46a1 -/- mice were in the opposite direction to those observed in efavirenz-treated vs control 5XFAD mice. Incubation of synaptosomal fractions with the inhibitors of glycogen synthase kinase 3, cyclin-dependent kinase 5, protein phosphatase 1/2A or calcineurin, and protein phosphatase 2B revealed that increased sterol flux in efavirenz-treated vs control 5XFAD mice affected the ability of all four enzymes to modulate glutamate release. In contrast, in Cyp46a1 -/- vs wild type mice, decreased sterol flux altered the ability of only cyclin-dependent kinase 5 and protein phosphatase 2B to regulate the glutamate release. Collectively, our results support cytochrome P450 46A1-mediated sterol flux as an important contributor to the fundamental properties of the membranes, protein phosphorylation, and synaptic transmission Also, our data provide an explanation of how one enzyme, cytochrome P450 46A1, can affect multiple pathways and processes and serve as a common potential target for several neurodegenerative disorders.
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Affiliation(s)
- Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH USA
| | - Young Li
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH USA
| | - John Denker
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH USA
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19
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Kishimoto T, Tomishige N, Murate M, Ishitsuka R, Schaller H, Mély Y, Ueda K, Kobayashi T. Cholesterol asymmetry at the tip of filopodia during cell adhesion. FASEB J 2020; 34:6185-6197. [PMID: 32162745 DOI: 10.1096/fj.201900065rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/26/2020] [Accepted: 02/26/2020] [Indexed: 12/28/2022]
Abstract
During adhesion, cells develop filopodia to facilitate the attachment to the extracellular matrix. The small guanosine triphosphate (GTP)-binding protein, Cdc42, plays a central role in the formation of filopodia. It has been reported that Cdc42 activity is regulated by cholesterol (Chol). We examined Chol distribution in filopodia using Chol-binding domain 4 (D4) fragment of bacterial toxin, perfringolysin O that senses high membrane concentration of Chol. Our results indicate that fluorescent D4 was enriched at the tip of the outer leaflet of filopodia in the initiation phase of cell adhesion. This enrichment was accompanied by a defect of D4 labeling in the inner leaflet. Steady phase adhered cell experiment indicated that both Cdc42 and ATP-binding cassette transporter, ABCA1, were involved in the binding of D4 to the cell surface. Depletion of Chol activated Cdc42. Our results suggest that asymmetric distribution of Chol at the tip of filopodia induces activation of Cdc42, and thus, facilitates filopodia formation.
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Affiliation(s)
- Takuma Kishimoto
- Lipid Biology Laboratory, RIKEN, Saitama, Japan.,Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Japan
| | - Nario Tomishige
- Lipid Biology Laboratory, RIKEN, Saitama, Japan.,UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
| | - Motohide Murate
- Lipid Biology Laboratory, RIKEN, Saitama, Japan.,UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
| | | | - Hubert Schaller
- Institut de Biologie Moléculaire des Plantes, UPR 2357, CNRS, Université de Strasbourg, Strasbourg, France
| | - Yves Mély
- UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
| | - Kazumitsu Ueda
- Division of Applied Life Sciences, Graduate School of Agriculture, Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto, Japan
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, Saitama, Japan.,UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
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20
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Boutry M, Pierga A, Matusiak R, Branchu J, Houllegatte M, Ibrahim Y, Balse E, El Hachimi KH, Brice A, Stevanin G, Darios F. Loss of spatacsin impairs cholesterol trafficking and calcium homeostasis. Commun Biol 2019; 2:380. [PMID: 31637311 PMCID: PMC6797781 DOI: 10.1038/s42003-019-0615-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 09/17/2019] [Indexed: 12/20/2022] Open
Abstract
Mutations in SPG11, leading to loss of spatacsin function, impair the formation of membrane tubules in lysosomes and cause lysosomal lipid accumulation. However, the full nature of lipids accumulating in lysosomes and the physiological consequences of such accumulation are unknown. Here we show that loss of spatacsin inhibits the formation of tubules on lysosomes and prevents the clearance of cholesterol from this subcellular compartment. Accumulation of cholesterol in lysosomes decreases cholesterol levels in the plasma membrane, enhancing the entry of extracellular calcium by store-operated calcium entry and increasing resting cytosolic calcium levels. Higher cytosolic calcium levels promote the nuclear translocation of the master regulator of lysosomes TFEB, preventing the formation of tubules and the clearance of cholesterol from lysosomes. Our work reveals a homeostatic balance between cholesterol trafficking and cytosolic calcium levels and shows that loss of spatacsin impairs this homeostatic equilibrium.
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Affiliation(s)
- Maxime Boutry
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
- Present Address: Cell Biology Program, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, ON Canada
| | - Alexandre Pierga
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
| | - Raphaël Matusiak
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
| | - Julien Branchu
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
| | - Marc Houllegatte
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Yoan Ibrahim
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
| | - Elise Balse
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1166, F-75013 Paris, France
| | - Khalid-Hamid El Hachimi
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Alexis Brice
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
| | - Giovanni Stevanin
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Frédéric Darios
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France
- Inserm, U1127, F-75013 Paris, France
- CNRS, UMR 7225, F-75013 Paris, France
- Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France
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21
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Functional link between plasma membrane spatiotemporal dynamics, cancer biology, and dietary membrane-altering agents. Cancer Metastasis Rev 2019; 37:519-544. [PMID: 29860560 DOI: 10.1007/s10555-018-9733-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The cell plasma membrane serves as a nexus integrating extra- and intracellular components, which together enable many of the fundamental cellular signaling processes that sustain life. In order to perform this key function, plasma membrane components assemble into well-defined domains exhibiting distinct biochemical and biophysical properties that modulate various signaling events. Dysregulation of these highly dynamic membrane domains can promote oncogenic signaling. Recently, it has been demonstrated that select membrane-targeted dietary bioactives (MTDBs) have the ability to remodel plasma membrane domains and subsequently reduce cancer risk. In this review, we focus on the importance of plasma membrane domain structural and signaling functionalities as well as how loss of membrane homeostasis can drive aberrant signaling. Additionally, we discuss the intricacies associated with the investigation of these membrane domain features and their associations with cancer biology. Lastly, we describe the current literature focusing on MTDBs, including mechanisms of chemoprevention and therapeutics in order to establish a functional link between these membrane-altering biomolecules, tuning of plasma membrane hierarchal organization, and their implications in cancer prevention.
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22
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Wilhelm LP, Voilquin L, Kobayashi T, Tomasetto C, Alpy F. Intracellular and Plasma Membrane Cholesterol Labeling and Quantification Using Filipin and GFP-D4. Methods Mol Biol 2019; 1949:137-152. [PMID: 30790254 DOI: 10.1007/978-1-4939-9136-5_11] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cholesterol, a major component of biological membranes, is rapidly trafficked and unevenly distributed between organelles. Anomalies of intracellular cholesterol distribution are the hallmark of a number of lysosomal lipid storage disorders. A major methodological obstacle for studying cholesterol trafficking is tracing this molecule in situ. The use of fluorescent probes that specifically bind cholesterol allows the visualization and imaging of cellular cholesterol. Here, we describe a series of assays optimized for quantifying free cholesterol in cell populations and at the single cell level, both at the plasma membrane and inside cells. These methods use two fluorescent probes: the D4 fragment of perfringolysin O fused to GFP (GFP-D4) and the polyene macrolide filipin. First, we report a robust method for quantifying plasma membrane cholesterol by flow cytometry using the GFP-D4 probe. Second, to optically distinguish and quantify intracellular cholesterol accumulation, we have adapted the classical filipin cholesterol staining protocol. Indeed, we observed that treatment of living cells with methyl-β-cyclodextrin, a chemical known to extract cholesterol from the plasma membrane, improves the visualization of the intracellular cholesterol pool with filipin. To complement these staining procedures, we developed an image analysis protocol based on image segmentation to quantify, in a robust manner, intracellular cholesterol stained with filipin. Thus, this chapter is a guideline for cellular cholesterol staining and signal quantification.
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Affiliation(s)
- Léa P Wilhelm
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Centre National de la Recherche Scientifique (CNRS), UMR7104 and Université de Strasbourg, Illkirch, France
| | - Laetitia Voilquin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Centre National de la Recherche Scientifique (CNRS), UMR7104 and Université de Strasbourg, Illkirch, France
| | - Toshihide Kobayashi
- Université de Strasbourg and Laboratory of Bioimaging and Pathologies, Centre National de la Recherche Scientifique (CNRS), UMR7021, Illkirch, France
| | - Catherine Tomasetto
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Centre National de la Recherche Scientifique (CNRS), UMR7104 and Université de Strasbourg, Illkirch, France.
| | - Fabien Alpy
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Centre National de la Recherche Scientifique (CNRS), UMR7104 and Université de Strasbourg, Illkirch, France.
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23
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Vesicular movements in the growth cone. Neurochem Int 2018; 119:71-76. [DOI: 10.1016/j.neuint.2017.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Revised: 08/29/2017] [Accepted: 09/24/2017] [Indexed: 01/03/2023]
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24
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Steck TL, Lange Y. Transverse distribution of plasma membrane bilayer cholesterol: Picking sides. Traffic 2018; 19:750-760. [PMID: 29896788 DOI: 10.1111/tra.12586] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/04/2018] [Accepted: 06/05/2018] [Indexed: 12/23/2022]
Abstract
The transverse asymmetry (sidedness) of phospholipids in plasma membrane bilayers is well characterized, distinctive, actively maintained and functionally important. In contrast, numerous studies using a variety of techniques have concluded that plasma membrane bilayer cholesterol is either mostly in the outer leaflet or the inner leaflet or is fairly evenly distributed. Sterols might simply partition according to their differing affinities for the asymmetrically disposed phospholipids, but some studies have proposed that it is actively transported to the outer leaflet. Other work suggests that the sterol is enriched in the inner leaflet, driven by either positive interactions with the phosphatidylethanolamine on that side or by its exclusion from the outer leaflet by the long chain sphingomyelin molecules therein. This uncertainty raises three questions: is plasma membrane cholesterol sidedness fixed in a given cell or cell type; is it generally the same among mammalian species; and does it serve specific physiological functions? This review grapples with these issues.
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Affiliation(s)
- Theodore L Steck
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois
| | - Yvonne Lange
- Department of Pathology, Rush University Medical Center, Chicago, Illinois
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25
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Interaction of Cholesterol with Perfringolysin O: What Have We Learned from Functional Analysis? Toxins (Basel) 2017; 9:toxins9120381. [PMID: 29168745 PMCID: PMC5744101 DOI: 10.3390/toxins9120381] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 12/27/2022] Open
Abstract
Cholesterol-dependent cytolysins (CDCs) constitute a family of pore-forming toxins secreted by Gram-positive bacteria. These toxins form transmembrane pores by inserting a large β-barrel into cholesterol-containing membranes. Cholesterol is absolutely required for pore-formation. For most CDCs, binding to cholesterol triggers conformational changes that lead to oligomerization and end in pore-formation. Perfringolysin O (PFO), secreted by Clostridium perfringens, is the prototype for the CDCs. The molecular mechanisms by which cholesterol regulates the cytolytic activity of the CDCs are not fully understood. In particular, the location of the binding site for cholesterol has remained elusive. We have summarized here the current body of knowledge on the CDCs-cholesterol interaction, with focus on PFO. We have employed sterols in aqueous solution to identify structural elements in the cholesterol molecule that are critical for its interaction with PFO. In the absence of high-resolution structural information, site-directed mutagenesis data combined with binding studies performed with different sterols, and molecular modeling are beginning to shed light on this interaction.
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26
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Mechanistic Insights into the Cholesterol-dependent Binding of Perfringolysin O-based Probes and Cell Membranes. Sci Rep 2017; 7:13793. [PMID: 29061991 PMCID: PMC5653841 DOI: 10.1038/s41598-017-14002-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/05/2017] [Indexed: 11/18/2022] Open
Abstract
Cholesterol distribution in the cell is maintained by both vesicular and non-vesicular sterol transport. Non-vesicular transport is mediated by the interaction of membrane-embedded cholesterol and water-soluble proteins. Small changes to the lipid composition of the membrane that do not change the total cholesterol content, can significantly affect how cholesterol interacts with other molecules at the surface of the membrane. The cholesterol-dependent cytolysin Perfringolysin O (PFO) constitutes a powerful tool to detect cholesterol in membranes, and the use of PFO-based probes has flourished in recent years. By using a non-lytic PFO derivative, we showed that the sensitivity of the probes for cholesterol can be tuned by modifications introduced directly in the membrane-interacting loops and/or by modifying residues away from the membrane-interacting domain. Through the use of these biosensors on live RAW 264.7 cells, we found that changes in the overall cholesterol content have a limited effect on the average cholesterol accessibility at the surface of the membrane. We showed that these exquisite biosensors report on changes in cholesterol reactivity at the membrane surface independently of the overall cholesterol content in the membrane.
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27
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Wilhelm LP, Wendling C, Védie B, Kobayashi T, Chenard MP, Tomasetto C, Drin G, Alpy F. STARD3 mediates endoplasmic reticulum-to-endosome cholesterol transport at membrane contact sites. EMBO J 2017; 36:1412-1433. [PMID: 28377464 PMCID: PMC5430228 DOI: 10.15252/embj.201695917] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 01/04/2023] Open
Abstract
StAR‐related lipid transfer domain‐3 (STARD3) is a sterol‐binding protein that creates endoplasmic reticulum (ER)–endosome contact sites. How this protein, at the crossroad between sterol uptake and synthesis pathways, impacts the intracellular distribution of this lipid was ill‐defined. Here, by using in situ cholesterol labeling and quantification, we demonstrated that STARD3 induces cholesterol accumulation in endosomes at the expense of the plasma membrane. STARD3‐mediated cholesterol routing depends both on its lipid transfer activity and its ability to create ER–endosome contacts. Corroborating this, in vitro reconstitution assays indicated that STARD3 and its ER‐anchored partner, Vesicle‐associated membrane protein‐associated protein (VAP), assemble into a machine that allows a highly efficient transport of cholesterol within membrane contacts. Thus, STARD3 is a cholesterol transporter scaffolding ER–endosome contacts and modulating cellular cholesterol repartition by delivering cholesterol to endosomes.
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Affiliation(s)
- Léa P Wilhelm
- Functional Genomics and Cancer Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U 964, Illkirch, France.,Centre National de la Recherche Scientifique (CNRS), UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Corinne Wendling
- Functional Genomics and Cancer Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U 964, Illkirch, France.,Centre National de la Recherche Scientifique (CNRS), UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Benoît Védie
- AP-HP (Assistance Publique - Hôpitaux de Paris), Hôpital Européen Georges Pompidou, Service de Biochimie, Paris, France
| | - Toshihide Kobayashi
- Université de Strasbourg, Illkirch, France.,Laboratory of Biophotonics and Pharmacology, Centre National de la Recherche Scientifique (CNRS), UMR 7213, Illkirch, France
| | - Marie-Pierre Chenard
- Functional Genomics and Cancer Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Service d'Anatomie Pathologique Générale, Centre Hospitalier Universitaire de Hautepierre, Strasbourg, France
| | - Catherine Tomasetto
- Functional Genomics and Cancer Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France .,Institut National de la Santé et de la Recherche Médicale (INSERM), U 964, Illkirch, France.,Centre National de la Recherche Scientifique (CNRS), UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Guillaume Drin
- Université Côte d'Azur, CNRS Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Fabien Alpy
- Functional Genomics and Cancer Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France .,Institut National de la Santé et de la Recherche Médicale (INSERM), U 964, Illkirch, France.,Centre National de la Recherche Scientifique (CNRS), UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France
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28
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Maekawa M. Domain 4 (D4) of Perfringolysin O to Visualize Cholesterol in Cellular Membranes-The Update. SENSORS 2017; 17:s17030504. [PMID: 28273804 PMCID: PMC5375790 DOI: 10.3390/s17030504] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 12/14/2022]
Abstract
The cellular membrane of eukaryotes consists of phospholipids, sphingolipids, cholesterol and membrane proteins. Among them, cholesterol is crucial for various cellular events (e.g., signaling, viral/bacterial infection, and membrane trafficking) in addition to its essential role as an ingredient of steroid hormones, vitamin D, and bile acids. From a micro-perspective, at the plasma membrane, recent emerging evidence strongly suggests the existence of lipid nanodomains formed with cholesterol and phospholipids (e.g., sphingomyelin, phosphatidylserine). Thus, it is important to elucidate how cholesterol behaves in membranes and how the behavior of cholesterol is regulated at the molecular level. To elucidate the complexed characteristics of cholesterol in cellular membranes, a couple of useful biosensors that enable us to visualize cholesterol in cellular membranes have been recently developed by utilizing domain 4 (D4) of Perfringolysin O (PFO, theta toxin), a cholesterol-binding toxin. This review highlights the current progress on development of novel cholesterol biosensors that uncover new insights of cholesterol in cellular membranes.
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Affiliation(s)
- Masashi Maekawa
- Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan.
- Division of Cell Growth and Tumor Regulation, Proteo-Science Center, Ehime University; Toon, Ehime 791-0295, Japan.
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29
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Abstract
Phagocytosis is a receptor-mediated process whereby professional phagocytes internalize invading pathogens and apoptotic bodies into an intracellular vacuole or phagosome, leading to their degradation. During the formation and maturation of the phagosome, several lipids undergo changes and effector proteins are recruited on the nascent phagosome in a concerted manner. These highly localized, dynamic, and transient processes can only be studied by methods capable of high spatial and temporal resolution. The use of genetically encoded chimeric constructs coupled with fluorescence confocal microscopy enables the continuous, noninvasive analysis of the distribution and metabolism of lipids and effector proteins during phagocytosis. Here, we describe a method where the mouse macrophage cell line, RAW 264.7, and primary macrophages are transiently transfected with fluorescent chimeric probes to analyze and quantify phagocytosis of immunoglobulin-opsonized particles, using confocal microscopy.
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Affiliation(s)
- Stella M Lu
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada, M5S 1A8
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, Canada, M5G 0A4
- Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, 290 Victoria Street, Toronto, ON, Canada, M5C 1N8
| | - Sergio Grinstein
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, Canada, M5G 0A4
- Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, 290 Victoria Street, Toronto, ON, Canada, M5C 1N8
| | - Gregory D Fairn
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada, M5S 1A8.
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, Canada, M5G 0A4.
- Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, 290 Victoria Street, Toronto, ON, Canada, M5C 1N8.
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30
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Venugopal S, Martinez-Arguelles DB, Chebbi S, Hullin-Matsuda F, Kobayashi T, Papadopoulos V. Plasma Membrane Origin of the Steroidogenic Pool of Cholesterol Used in Hormone-induced Acute Steroid Formation in Leydig Cells. J Biol Chem 2016; 291:26109-26125. [PMID: 27815506 DOI: 10.1074/jbc.m116.740928] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 11/03/2016] [Indexed: 02/05/2023] Open
Abstract
Hormone-sensitive acute steroid biosynthesis requires trafficking of cholesterol from intracellular sources to the inner mitochondrial membrane. The precise location of the intracellular cholesterol and its transport mechanism are uncertain. Perfringolysin O, produced by Clostridium perfringens, binds cholesterol. Its fourth domain (D4) retains cholesterol-binding properties but not cytotoxicity. We transfected steroidogenic MA-10 cells of mouse Leydig cell tumors with the mCherry-D4 plasmid. Tagged D4 with fluorescent proteins enabled us to track cholesterol. The staining was primarily localized to the inner leaflet of the plasma membrane and was partially released upon treatment with dibutyryl-cAMP (Bt2cAMP), a cAMP analog. Inhibitors of cholesterol import into mitochondria blocked steroidogenesis and prevented release of D4 (and presumably cholesterol) from the plasma membrane. We conclude that the bulk of the steroidogenic pool of cholesterol, mobilized by Bt2cAMP for acute steroidogenesis, originates from the plasma membrane. Treatment of the cells with steroid metabolites, 22(R)-hydroxycholesterol and pregnenolone, also reduced D4 release from the plasma membrane, perhaps evidence for a feedback effect of elevated steroid formation on cholesterol release. Interestingly, D4 staining was localized to endosomes during Bt2cAMP stimulation suggesting that these organelles are on the route of cholesterol trafficking from the plasma membrane to mitochondria. Finally, D4 was expressed in primary rat Leydig cells with a lentivirus and was released from the plasma membrane following Bt2cAMP treatment. We conclude that the plasma membrane is the source of cholesterol for steroidogenesis in these cells as well as in MA-10 cells.
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Affiliation(s)
- Sathvika Venugopal
- From the Research Institute of the McGill University Health Centre and the Department of Medicine, McGill University, Montreal H4A 3J1, Canada
| | - Daniel Benjamin Martinez-Arguelles
- From the Research Institute of the McGill University Health Centre and the Department of Medicine, McGill University, Montreal H4A 3J1, Canada
| | - Seimia Chebbi
- From the Research Institute of the McGill University Health Centre and the Department of Medicine, McGill University, Montreal H4A 3J1, Canada
| | - Françoise Hullin-Matsuda
- the Lipid Biology Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198, Japan.,INSERM U1060, Université Lyon 1, INSA Lyon, 69621 Villeurbanne, France
| | - Toshihide Kobayashi
- the Lipid Biology Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198, Japan.,INSERM U1060, Université Lyon 1, INSA Lyon, 69621 Villeurbanne, France.,UMR 7213 CNRS, University of Strasbourg, 67401 Illkirch, France, and
| | - Vassilios Papadopoulos
- From the Research Institute of the McGill University Health Centre and the Department of Medicine, McGill University, Montreal H4A 3J1, Canada, .,the Departments of Pharmacology and Therapeutics and.,Biochemistry, McGill University, Montreal H3G 1Y6, Canada
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31
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Riedel BC, Thompson PM, Brinton RD. Age, APOE and sex: Triad of risk of Alzheimer's disease. J Steroid Biochem Mol Biol 2016; 160:134-47. [PMID: 26969397 PMCID: PMC4905558 DOI: 10.1016/j.jsbmb.2016.03.012] [Citation(s) in RCA: 364] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Revised: 03/02/2016] [Accepted: 03/06/2016] [Indexed: 02/06/2023]
Abstract
Age, apolipoprotein E ε4 (APOE) and chromosomal sex are well-established risk factors for late-onset Alzheimer's disease (LOAD; AD). Over 60% of persons with AD harbor at least one APOE-ε4 allele. The sex-based prevalence of AD is well documented with over 60% of persons with AD being female. Evidence indicates that the APOE-ε4 risk for AD is greater in women than men, which is particularly evident in heterozygous women carrying one APOE-ε4 allele. Paradoxically, men homozygous for APOE-ε4 are reported to be at greater risk for mild cognitive impairment and AD. Herein, we discuss the complex interplay between the three greatest risk factors for Alzheimer's disease, age, APOE-ε4 genotype and chromosomal sex. We propose that the convergence of these three risk factors, and specifically the bioenergetic aging perimenopause to menopause transition unique to the female, creates a risk profile for AD unique to the female. Further, we discuss the specific risk of the APOE-ε4 positive male which appears to emerge early in the aging process. Evidence for impact of the triad of AD risk factors is most evident in the temporal trajectory of AD progression and burden of pathology in relation to APOE genotype, age and sex. Collectively, the data indicate complex interactions between age, APOE genotype and gender that belies a one size fits all approach and argues for a precision medicine approach that integrates across the three main risk factors for Alzheimer's disease.
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Affiliation(s)
- Brandalyn C Riedel
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Paul M Thompson
- USC Institute for Neuroimaging and Informatics, University of Southern California, Marina del Rey, CA 90292, USA
| | - Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
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32
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Weber DK, Yao S, Rojko N, Anderluh G, Lybrand TP, Downton MT, Wagner J, Separovic F. Characterization of the Lipid-Binding Site of Equinatoxin II by NMR and Molecular Dynamics Simulation. Biophys J 2016; 108:1987-96. [PMID: 25902438 DOI: 10.1016/j.bpj.2015.03.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/09/2015] [Accepted: 03/12/2015] [Indexed: 12/26/2022] Open
Abstract
Equinatoxin II (EqtII) is a soluble, 20 kDa pore-forming protein toxin isolated from the sea anemone Actinia equina. Although pore formation has long been known to occur in distinct stages, including monomeric attachment to phospholipid membranes followed by detachment of the N-terminal helical domain and oligomerization into the final pore assembly, atomistic-level detail of the protein-lipid interactions underlying these events remains elusive. Using high-resolution solution state NMR of uniformly-(15)N-labeled EqtII at the critical micelle concentration of dodecylphosphocholine, we have mapped the lipid-binding site through chemical shift perturbations. Subsequent docking of an EqtII monomer onto a dodecylphosphocholine micelle, followed by 400 ns of all-atom molecular dynamics simulation, saw several high-occupancy lipid-binding pockets stabilized by cation-π, hydrogen bonding, and hydrophobic interactions; and stabilization of the loop housing the conserved arginine-glycine-aspartate motif. Additional simulation of EqtII with an N-acetyl sphingomyelin micelle, for which high-resolution NMR data cannot be obtained due to aggregate formation, revealed that sphingomyelin specificity might occur via hydrogen bonding to the 3-OH and 2-NH groups unique to the ceramide backbone by side chains of D109 and Y113; and main chains of P81 and W112. Furthermore, a binding pocket formed by K30, K77, and P81, proximate to the hinge region of the N-terminal helix, was identified and may be implicated in triggering pore formation.
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Affiliation(s)
- Daniel K Weber
- School of Chemistry, University of Melbourne, Victoria, Australia; Bio21 Institute, University of Melbourne, Victoria, Australia
| | - Shenggen Yao
- Bio21 Institute, University of Melbourne, Victoria, Australia
| | - Nejc Rojko
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Gregor Anderluh
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Terry P Lybrand
- Center for Structural Biology, Department of Chemistry, Vanderbilt University, Nashville, Tennessee
| | - Matthew T Downton
- IBM Research Collaboratory for Life Sciences, Victorian Life Sciences Computation Initiative, University of Melbourne, Victoria, Australia
| | - John Wagner
- IBM Research Collaboratory for Life Sciences, Victorian Life Sciences Computation Initiative, University of Melbourne, Victoria, Australia
| | - Frances Separovic
- School of Chemistry, University of Melbourne, Victoria, Australia; Bio21 Institute, University of Melbourne, Victoria, Australia.
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33
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Villar VAM, Cuevas S, Zheng X, Jose PA. Localization and signaling of GPCRs in lipid rafts. Methods Cell Biol 2016; 132:3-23. [DOI: 10.1016/bs.mcb.2015.11.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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34
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Abstract
Pore forming toxins (PFTs) evolved to permeate the plasma membrane of target cells. This is achieved in a multistep mechanism that usually involves binding of soluble protein monomer to the lipid membrane, oligomerization at the plane of the membrane, and insertion of part of the polypeptide chain across the lipid membrane to form a conductive channel. Introduced pores allow uncontrolled transport of solutes across the membrane, inflicting damage to the target cell. PFTs are usually studied from the perspective of structure-function relationships, often neglecting the important role of the bulk membrane properties on the PFT mechanism of action. In this Account, we discuss how membrane lateral heterogeneity, thickness, and fluidity influence the pore forming process of PFTs. In general, lipid molecules are more accessible for binding in fluid membranes due to steric reasons. When PFT specifically binds ordered domains, it usually recognizes a specific lipid distribution pattern, like sphingomyelin (SM) clusters or SM/cholesterol complexes, and not individual lipid species. Lipid domains were also suggested to act as an additional concentration platform facilitating PFT oligomerization, but this is yet to be shown. The last stage in PFT action is the insertion of the transmembrane segment across the membranes to build the transmembrane pore walls. Conformational changes are a spontaneous process, and sufficient free energy has to be available for efficient membrane penetration. Therefore, fluid bilayers are permeabilized more readily in comparison to highly ordered and thicker liquid ordered lipid phase (Lo). Energetically more costly insertion into the Lo phase can be driven by the hydrophobic mismatch between the thinner liquid disordered phase (Ld) and large protein complexes, which are unable to tilt like single transmembrane segments. In the case of proteolipid pores, membrane properties can directly modulate pore size, stability, and even selectivity. Finally, events associated with pore formation can modulate properties of the lipid membrane and affect its organization. Model membranes do not necessarily reproduce the physicochemical properties of the native cellular membrane, and caution is needed when transferring results from model to native lipid membranes. In this context, the utilization of novel approaches that enable studying PFTs on living cells at a single molecule level should reveal complex protein-lipid membrane interactions in greater detail.
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Affiliation(s)
- Nejc Rojko
- Laboratory
for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Gregor Anderluh
- Laboratory
for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
- Department
of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva
101, 1000 Ljubljana, Slovenia
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35
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Carquin M, Conrard L, Pollet H, Van Der Smissen P, Cominelli A, Veiga-da-Cunha M, Courtoy PJ, Tyteca D. Cholesterol segregates into submicrometric domains at the living erythrocyte membrane: evidence and regulation. Cell Mol Life Sci 2015; 72:4633-51. [PMID: 26077601 PMCID: PMC11113096 DOI: 10.1007/s00018-015-1951-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 05/07/2015] [Accepted: 06/04/2015] [Indexed: 01/01/2023]
Abstract
Although cholesterol is essential for membrane fluidity and deformability, the level of its lateral heterogeneity at the plasma membrane of living cells is poorly understood due to lack of appropriate probe. We here report on the usefulness of the D4 fragment of Clostridium perfringens toxin fused to mCherry (theta*), as specific, non-toxic, sensitive and quantitative cholesterol-labeling tool, using erythrocyte flat membrane. By confocal microscopy, theta* labels cholesterol-enriched submicrometric domains in coverslip-spread but also gel-suspended (non-stretched) fresh erythrocytes, suggesting in vivo relevance. Cholesterol domains on spread erythrocytes are stable in time and space, restricted by membrane:spectrin anchorage via 4.1R complexes, and depend on temperature and sphingomyelin, indicating combined regulation by extrinsic membrane:cytoskeleton interaction and by intrinsic lipid packing. Cholesterol domains partially co-localize with BODIPY-sphingomyelin-enriched domains. In conclusion, we show that theta* is a useful vital probe to study cholesterol organization and demonstrate that cholesterol forms submicrometric domains in living cells.
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Affiliation(s)
- Mélanie Carquin
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Louise Conrard
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Hélène Pollet
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Patrick Van Der Smissen
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Antoine Cominelli
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Maria Veiga-da-Cunha
- Laboratory of Physiological Chemistry, de Duve Institute and Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Pierre J Courtoy
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium
| | - Donatienne Tyteca
- CELL Unit, de Duve Institute and Université Catholique de Louvain, UCL B1.75.05, Avenue Hippocrate, 75, 1200, Brussels, Belgium.
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36
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Fang RH, Luk BT, Hu CMJ, Zhang L. Engineered nanoparticles mimicking cell membranes for toxin neutralization. Adv Drug Deliv Rev 2015; 90:69-80. [PMID: 25868452 DOI: 10.1016/j.addr.2015.04.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/08/2015] [Accepted: 04/01/2015] [Indexed: 11/27/2022]
Abstract
Protein toxins secreted from pathogenic bacteria and venomous animals rely on multiple mechanisms to overcome the cell membrane barrier to inflict their virulence effect. A promising therapeutic concept toward developing a broadly applicable anti-toxin platform is to administer cell membrane mimics as decoys to sequester these virulence factors. As such, lipid membrane-based nanoparticulates are an ideal candidate given their structural similarity to cellular membranes. This article reviews the virulence mechanisms employed by toxins at the cell membrane interface and highlights the application of cell-membrane mimicking nanoparticles as toxin decoys for systemic detoxification. In addition, the implication of particle/toxin nanocomplexes in the development of toxoid vaccines is discussed.
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37
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Perfringolysin O: The Underrated Clostridium perfringens Toxin? Toxins (Basel) 2015; 7:1702-21. [PMID: 26008232 PMCID: PMC4448169 DOI: 10.3390/toxins7051702] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 05/08/2015] [Indexed: 12/21/2022] Open
Abstract
The anaerobic bacterium Clostridium perfringens expresses multiple toxins that promote disease development in both humans and animals. One such toxin is perfringolysin O (PFO, classically referred to as θ toxin), a pore-forming cholesterol-dependent cytolysin (CDC). PFO is secreted as a water-soluble monomer that recognizes and binds membranes via cholesterol. Membrane-bound monomers undergo structural changes that culminate in the formation of an oligomerized prepore complex on the membrane surface. The prepore then undergoes conversion into the bilayer-spanning pore measuring approximately 250–300 Å in diameter. PFO is expressed in nearly all identified C. perfringens strains and harbors interesting traits that suggest a potential undefined role for PFO in disease development. Research has demonstrated a role for PFO in gas gangrene progression and bovine necrohemorrhagic enteritis, but there is limited data available to determine if PFO also functions in additional disease presentations caused by C. perfringens. This review summarizes the known structural and functional characteristics of PFO, while highlighting recent insights into the potential contributions of PFO to disease pathogenesis.
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38
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Morante K, Caaveiro JMM, Tanaka K, González-Mañas JM, Tsumoto K. A pore-forming toxin requires a specific residue for its activity in membranes with particular physicochemical properties. J Biol Chem 2015; 290:10850-61. [PMID: 25759390 DOI: 10.1074/jbc.m114.615211] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Indexed: 12/29/2022] Open
Abstract
The physicochemical landscape of the bilayer modulates membrane protein function. Actinoporins are a family of potent hemolytic proteins from sea anemones acting at the membrane level. This family of cytolysins preferentially binds to target membranes containing sphingomyelin, where they form lytic pores giving rise to cell death. Although the cytolytic activity of the actinoporin fragaceatoxin C (FraC) is sensitive to vesicles made of various lipid compositions, it is far from clear how this toxin adjusts its mechanism of action to a broad range of physiochemical landscapes. Herein, we show that the conserved residue Phe-16 of FraC is critical for pore formation in cholesterol-rich membranes such as those of red blood cells. The interaction of a panel of muteins of Phe-16 with model membranes composed of raft-like lipid domains is inactivated in cholesterol-rich membranes but not in cholesterol-depleted membranes. These results indicate that actinoporins recognize different membrane environments, resulting in a wider repertoire of susceptible target membranes (and preys) for sea anemones. In addition, this study has unveiled promising candidates for the development of protein-based biosensors highly sensitive to the concentration of cholesterol within the membrane.
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Affiliation(s)
- Koldo Morante
- From the Department of Bioengineering, Graduate School of Engineering and the Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain, and
| | - Jose M M Caaveiro
- From the Department of Bioengineering, Graduate School of Engineering and
| | - Koji Tanaka
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Juan Manuel González-Mañas
- the Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain, and
| | - Kouhei Tsumoto
- From the Department of Bioengineering, Graduate School of Engineering and Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan, the Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku, 108-8639 Tokyo, Japan
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39
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Lin Q, London E. Transmembrane protein (perfringolysin o) association with ordered membrane domains (rafts) depends upon the raft-associating properties of protein-bound sterol. Biophys J 2014; 105:2733-42. [PMID: 24359745 DOI: 10.1016/j.bpj.2013.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 10/29/2013] [Accepted: 11/01/2013] [Indexed: 02/07/2023] Open
Abstract
Because transmembrane (TM) protein localization, or nonlocalization, in ordered membrane domains (rafts) is a key to understanding membrane domain function, it is important to define the origin of protein-raft interaction. One hypothesis is that a tight noncovalent attachment of TM proteins to lipids that have a strong affinity for ordered domains can be sufficient to induce raft-protein interaction. The sterol-binding protein perfringolysin O (PFO) was used to test this hypothesis. PFO binds both to sterols that tend to localize in ordered domains (e.g., cholesterol), and to those that do not (e.g., coprostanol), but it does not bind to epicholesterol, a raft-promoting 3α-OH sterol. Using a fluorescence resonance energy transfer assay in model membrane vesicles containing coexisting ordered and disordered lipid domains, both TM and non-TM forms of PFO were found to concentrate in ordered domains in vesicles containing high and low-Tm lipids plus cholesterol or 1:1 (mol/mol) cholesterol/epicholesterol, whereas they concentrate in disordered domains in vesicles containing high-Tm and low-Tm lipids plus 1:1 (mol/mol) coprostanol/epicholesterol. Combined with previous studies this behavior indicates that TM protein association with ordered domains is dependent upon both the association of the protein-bound sterol with ordered domains and hydrophobic match between TM segments and rafts.
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Affiliation(s)
- Qingqing Lin
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York
| | - Erwin London
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York.
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40
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Kwiatkowska K, Marszałek–Sadowska E, Traczyk G, Koprowski P, Musielak M, Ługowska A, Kulma M, Grzelczyk A, Sobota A. Visualization of cholesterol deposits in lysosomes of Niemann-Pick type C fibroblasts using recombinant perfringolysin O. Orphanet J Rare Dis 2014; 9:64. [PMID: 24775609 PMCID: PMC4005833 DOI: 10.1186/1750-1172-9-64] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 04/16/2014] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Niemann-Pick disease type C (NPC) is caused by defects in cholesterol efflux from lysosomes due to mutations of genes coding for NPC1 and NPC2 proteins. As a result, massive accumulation of unesterified cholesterol in late endosomes/lysosomes is observed. At the level of the organism these cholesterol metabolism disorders are manifested by progressive neurodegeneration and hepatosplenomegaly. Until now filipin staining of cholesterol deposits in cells has been widely used for NPC diagnostics. In this report we present an alternative method for cholesterol visualization and estimation using a cholesterol-binding bacterial toxin, perfringolysin O. METHODS To detect cholesterol deposits, a recombinant probe, perfringolysin O fused with glutathione S-transferase (GST-PFO) was prepared. GST-PFO followed by labeled antibodies or streptavidin was applied for immunofluorescence and immunoelectron microscopy to analyze cholesterol distribution in cells derived from NPC patients. The identity of GST-PFO-positive structures was revealed by a quantitative analysis of their colocalization with several organelle markers. Cellular ELISA using GST-PFO was developed to estimate the level of unesterified cholesterol in NPC cells. RESULTS GST-PFO recognized cholesterol with high sensitivity and selectivity, as demonstrated by a protein/lipid overlay assay and surface plasmon resonance analysis. When applied to stain NPC cells, GST-PFO decorated abundant deposits of cholesterol in intracellular vesicles that colocalized with filipin-positive structures. These cholesterol deposits were resistant to 0.05%-0.2% Triton X-100 used for cells permeabilization in the staining procedure. GST-PFO-stained organelles were identified as late endosomes/lysosomes based on their colocalization with LAMP-1 and lysobisphosphatidic acid. On the other hand, GST-PFO did not colocalize with markers of the Golgi apparatus, endoplasmic reticulum, peroxisomes or with actin filaments. Only negligible GST-PFO staining was seen in fibroblasts of healthy individuals. When applied to cellular ELISA, GST-PFO followed by anti-GST-peroxidase allowed a semiquantitative analysis of cholesterol level in cells of NPC patients. Binding of GST-PFO to NPC cells was nearly abolished after extraction of cholesterol with methyl-β-cyclodextrin. CONCLUSIONS Our data indicate that a recombinant protein GST-PFO can be used to detect cholesterol accumulated in NPC cells by immunofluorescence and cellular ELISA. GST-PFO can be a convenient and reliable probe for revealing cholesterol deposits in cells and can be useful in diagnostics of NPC disease.
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Affiliation(s)
- Katarzyna Kwiatkowska
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Ewelina Marszałek–Sadowska
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Gabriela Traczyk
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Piotr Koprowski
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Małgorzata Musielak
- Department of Genetics, Institute of Psychiatry and Neurology, 9 Sobieskiego St., 02-957 Warsaw, Poland
| | - Agnieszka Ługowska
- Department of Genetics, Institute of Psychiatry and Neurology, 9 Sobieskiego St., 02-957 Warsaw, Poland
| | - Magdalena Kulma
- Institute of Biochemistry and Biophysics, 5a Pawinskiego St., 02-106 Warsaw, Poland
| | - Anna Grzelczyk
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Andrzej Sobota
- Department of Cell Biology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
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41
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Abstract
The cell membrane is crucial for protection of the cell from its environment. MACPF/CDC proteins are a large superfamily known to be essential for bacterial pathogenesis and proper functioning of the immune system. The three most studied groups of MACPF/CDC proteins are cholesterol-dependent cytolysins from bacteria, the membrane attack complex of complement and human perforin. Their primary function is to form transmembrane pores in target cell membranes. The common mechanism of action comprises water-soluble monomeric proteins binding to the host cell membrane, oligomerization, and formation of a functional pore. This causes a disturbance in gradients of ions and other molecules across the membrane and can lead to cell death. Cells react to this form of attack in a complex manner. Responses can be general, like removing the perforated part of the membrane, or more specific, in many cases depending on binding of proteins to specific receptors to trigger various signalling cascades.
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42
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Johnson BB, Heuck AP. Perfringolysin O structure and mechanism of pore formation as a paradigm for cholesterol-dependent cytolysins. Subcell Biochem 2014; 80:63-81. [PMID: 24798008 DOI: 10.1007/978-94-017-8881-6_5] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cholesterol-dependent cytolysins (CDCs) constitute a family of pore forming toxins secreted by Gram-positive bacteria. These toxins form transmembrane pores by inserting a large β-barrel into cholesterol-containing membrane bilayers. Binding of water-soluble CDCs to the membrane triggers the formation of oligomers containing 35-50 monomers. The coordinated insertion of more than seventy β-hairpins into the membrane requires multiple structural conformational changes. Perfringolysin O (PFO), secreted by Clostridium perfringens, has become the prototype for the CDCs. In this chapter, we will describe current knowledge on the mechanism of PFO cytolysis, with special focus on cholesterol recognition, oligomerization, and the conformational changes involved in pore formation.
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Affiliation(s)
- Benjamin B Johnson
- Department of Biochemistry and Molecular Biology, University of Massachusetts, 710 N. Pleasant St., Lederle GRT, Amherst, MA, 01003, USA
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43
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Johnson BB, Moe PC, Wang D, Rossi K, Trigatti BL, Heuck AP. Modifications in Perfringolysin O Domain 4 Alter the Cholesterol Concentration Threshold Required for Binding. Biochemistry 2012; 51:3373-82. [DOI: 10.1021/bi3003132] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
| | | | - David Wang
- Department of Biochemistry and
Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Kathleen Rossi
- Department of Biochemistry and
Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Bernardo L. Trigatti
- Department of Biochemistry and
Biomedical Sciences, McMaster University, Hamilton, ON, Canada
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44
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Lokar M, Kabaso D, Resnik N, Sepčić K, Kralj-Iglič V, Veranič P, Zorec R, Iglič A. The role of cholesterol-sphingomyelin membrane nanodomains in the stability of intercellular membrane nanotubes. Int J Nanomedicine 2012; 7:1891-902. [PMID: 22605937 PMCID: PMC3352693 DOI: 10.2147/ijn.s28723] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Intercellular membrane nanotubes (ICNs) are highly curved tubular structures that connect neighboring cells. The stability of these structures depends on the inner cytoskeleton and the cell membrane composition. Yet, due to the difficulty in the extraction of ICNs, the cell membrane composition remains elusive. In the present study, a raft marker, ostreolysin, revealed the enrichment of cholesterol-sphingomyelin membrane nanodomains along ICNs in a T24 (malignant) urothelial cancer cell line. Cholesterol depletion, due to the addition of methyl-β-cyclodextrin, caused the dispersion of cholesterol-sphingomyelin membrane nanodomains and the retraction of ICNs. The depletion of cholesterol also led to cytoskeleton reorganization and to formation of actin stress fibers. Live cell imaging data revealed the possible functional coupling between the change from polygonal to spherical shape, cell separation, and the disconnection of ICNs. The ICN was modeled as an axisymmetric tubular structure, enabling us to investigate the effects of cholesterol content on the ICN curvature. The removal of cholesterol was predicted to reduce the positive spontaneous curvature of the remaining membrane components, increasing their curvature mismatch with the tube curvature. The mechanisms by which the increased curvature mismatch could contribute to the disconnection of ICNs are discussed.
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Affiliation(s)
- Maruša Lokar
- Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
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45
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Abstract
Endosomes along the degradation pathway exhibit a multivesicular appearance and differ in their lipid compositions. Association of proteins to specific membrane lipids and presumably also lipid-lipid interactions contribute to the formation of functional membrane platforms that regulate endosome biogenesis and function. This chapter provides a brief review of the functions of endosomal lipids in the degradation pathway, a discussion of techniques that allow studying lipid-based mechanisms and a selection of step-by-step protocols for in vivo and in vitro methods commonly used to study lipid roles in endocytosis. The techniques described here have been used to elucidate the function of the late endosomal lipid lysobisphosphatidic acid and allow the monitoring of lipid distribution, levels and dynamics, as well as the characterization of lipid-binding partners.
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46
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Ishitsuka R, Saito T, Osada H, Ohno-Iwashita Y, Kobayashi T. Fluorescence image screening for chemical compounds modifying cholesterol metabolism and distribution. J Lipid Res 2011; 52:2084-94. [PMID: 21862703 DOI: 10.1194/jlr.d018184] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
An automated fluorescence microscopy assay using a nontoxic cholesterol binding protein, toxin domain 4, (D4), was developed in order to identify chemical compounds modifying intracellular cholesterol metabolism and distribution. Using this method, we screened a library of 1,056 compounds and identified 35 compounds that decreased D4 binding to the cell surface. Among them, 8 compounds were already reported to alter the biosynthesis or the intracellular distribution of cholesterol. The remaining 27 hit compounds were further analyzed biochemically and histochemically. Cell staining with another fluorescent cholesterol probe, filipin, revealed that 17 compounds accumulated cholesterol in the late endosomes. Five compounds decreased cholesterol biosynthesis, and two compounds inhibited the binding of D4 to the membrane. This visual screening method, based on the cholesterol-specific probe D4 in combination with biochemical analyses, is a cell-based, sensitive technique for identifying new chemical compounds and modifying cholesterol distribution and metabolism. Furthermore, it is suitable for high-throughput analysis for drug discovery.
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Affiliation(s)
- Reiko Ishitsuka
- Lipid Biology Laboratory, RIKEN Advanced Science Institute, Wako-shi, Saitama 351-0198, Japan
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47
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Nelson LD, Chiantia S, London E. Perfringolysin O association with ordered lipid domains: implications for transmembrane protein raft affinity. Biophys J 2011; 99:3255-63. [PMID: 21081073 DOI: 10.1016/j.bpj.2010.09.028] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 09/03/2010] [Accepted: 09/16/2010] [Indexed: 12/15/2022] Open
Abstract
Upon interaction with cholesterol, perfringolysin O (PFO) inserts into membranes and forms a rigid transmembrane (TM) β-barrel. PFO is believed to interact with liquid ordered lipid domains (lipid rafts). Because the origin of TM protein affinity for rafts is poorly understood, we investigated PFO raft affinity in vesicles having coexisting ordered and disordered lipid domains. Fluorescence resonance energy transfer (FRET) from PFO Trp to domain-localized acceptors indicated that PFO generally has a raft affinity between that of LW peptide (low raft affinity) and cholera toxin B (high raft affinity) in vesicles containing ordered domains rich in brain sphingomyelin or distearoylphosphatidylcholine. FRET also showed that ceramide, which increases exposure of cholesterol to water and thus displaces it from rafts, does not displace PFO from ordered domains. This can be explained by shielding of PFO-bound cholesterol from water. Finally, FRET showed that PFO affinity for ordered domains was higher in its non-TM (prepore) form than in its TM form, demonstrating that the TM portion of PFO interacts unfavorably with rafts. Microscopy studies in giant unilamellar vesicles confirmed that PFO exhibits intermediate raft affinity, and showed that TM PFO (but not non-TM PFO) concentrated at the edges of liquid ordered domains. These studies suggest that a combination of binding to raft-associating molecules and having a rigid TM structure that is unable to pack well in a highly ordered lipid environment can control TM protein domain localization. To accommodate these constraints, raft-associated TM proteins in cells may tend to locate within liquid disordered shells encapsulated within ordered domains.
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Affiliation(s)
- Lindsay D Nelson
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA
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48
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Navratil AM, Bliss SP, Roberson MS. Membrane rafts and GnRH receptor signaling. Brain Res 2010; 1364:53-61. [PMID: 20836995 DOI: 10.1016/j.brainres.2010.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 08/31/2010] [Accepted: 09/02/2010] [Indexed: 10/19/2022]
Abstract
The binding of hypothalamic gonadotropin-releasing hormone (GnRH) to the pituitary GnRH receptor (GnRHR) is essential for reproductive function by stimulating the synthesis and secretion of gonadotropic hormones, luteinizing hormone (LH) and follicle stimulating hormone (FSH). Engagement of the GnRHR by GnRH initiates a complex series of signaling events that include the activation of various mitogen-activated protein kinase (MAPK) pathways, including extracellular signal-regulated kinase (ERK). GnRHR signaling is thought to initiate within specialized microdomains in the plasma membrane termed membrane rafts. These microdomains are enriched in sphingolipid and cholesterol and are believed to be highly dynamic organizing centers for receptors and their cognate signaling molecules associated with the plasma membrane. Within this review we discuss the composition and role of membrane rafts in cell signaling and examine evidence that the mammalian type I GnRHR is constitutively and exclusively localized to these membrane microdomains in various experimental models. We conclude that membrane raft composition and organization potentially underlie the functional ability of GnRH to elicit the assembly of multi-protein signaling complexes necessary for downstream signaling to the ERK pathway that ultimately is critical for controlling fertility.
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Affiliation(s)
- Amy M Navratil
- Department of Biomedical Sciences, T4-018 Veterinary Research Tower, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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49
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Harris JR, Lewis RJ, Baik C, Pokrajac L, Billington SJ, Palmer M. Cholesterol microcrystals and cochleate cylinders: attachment of pyolysin oligomers and domain 4. J Struct Biol 2010; 173:38-45. [PMID: 20682347 DOI: 10.1016/j.jsb.2010.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 07/16/2010] [Accepted: 07/27/2010] [Indexed: 11/15/2022]
Abstract
Using an established organic solvent injection procedure for the preparation of aqueous cholesterol microcrystal suspensions, it has now been shown that a new, hollow, cylindrical, tightly-coiled, multi-bilayer form of cholesterol can be generated, termed the cochleate cylinder. Cholesterol cochleate cylinders are formed in larger numbers at intermediate temperatures (40-75°C) but are not formed at 100°C. The structure of the cholesterol microcrystals and cochleate cylinders is shown in negatively stained electron micrographs. Oligomerization and attachment of pyolysin to cholesterol microcrystals and cochleate cylinders is shown, as is the attachment of the pyolysin "cholesterol-binding" domain 4 (D4) fragment. The bound D4 domain forms a linear array on the two planar surfaces and edges of the cholesterol microcrystals and a quasi helical array on the surface of the cochleate cylinders. Little evidence has been obtained to support the possibility that interaction or hetero-oligomerization can occur between intact pyolysin and the pyolysin D4 fragment on the surface of cholesterol microcrystals. Using immobilized cholesterol crystals attached to a carbon support film, single-sided linear labelling of the cholesterol surface with pyolysin D4 has been achieved, which correlates well with the images from the microcrystal suspensions and our earlier data using non-cytolytic streptolysin O mutants.
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Affiliation(s)
- J Robin Harris
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle-upon-Tyne NE2 4HH, UK.
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50
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Ohno-Iwashita Y, Shimada Y, Hayashi M, Inomata M. Plasma membrane microdomains in aging and disease. Geriatr Gerontol Int 2010; 10 Suppl 1:S41-52. [DOI: 10.1111/j.1447-0594.2010.00600.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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