1
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Feng S, Park S, Choi YK, Im W. CHARMM-GUI Membrane Builder: Past, Current, and Future Developments and Applications. J Chem Theory Comput 2023; 19:2161-2185. [PMID: 37014931 PMCID: PMC10174225 DOI: 10.1021/acs.jctc.2c01246] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023]
Abstract
Molecular dynamics simulations of membranes and membrane proteins serve as computational microscopes, revealing coordinated events at the membrane interface. As G protein-coupled receptors, ion channels, transporters, and membrane-bound enzymes are important drug targets, understanding their drug binding and action mechanisms in a realistic membrane becomes critical. Advances in materials science and physical chemistry further demand an atomistic understanding of lipid domains and interactions between materials and membranes. Despite a wide range of membrane simulation studies, generating a complex membrane assembly remains challenging. Here, we review the capability of CHARMM-GUI Membrane Builder in the context of emerging research demands, as well as the application examples from the CHARMM-GUI user community, including membrane biophysics, membrane protein drug-binding and dynamics, protein-lipid interactions, and nano-bio interface. We also provide our perspective on future Membrane Builder development.
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Affiliation(s)
- Shasha Feng
- Departments of Biological Sciences and Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Soohyung Park
- Departments of Biological Sciences and Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Yeol Kyo Choi
- Departments of Biological Sciences and Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Wonpil Im
- Departments of Biological Sciences and Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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2
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Revie NM, Iyer KR, Maxson ME, Zhang J, Yan S, Fernandes CM, Meyer KJ, Chen X, Skulska I, Fogal M, Sanchez H, Hossain S, Li S, Yashiroda Y, Hirano H, Yoshida M, Osada H, Boone C, Shapiro RS, Andes DR, Wright GD, Nodwell JR, Del Poeta M, Burke MD, Whitesell L, Robbins N, Cowen LE. Targeting fungal membrane homeostasis with imidazopyrazoindoles impairs azole resistance and biofilm formation. Nat Commun 2022; 13:3634. [PMID: 35752611 PMCID: PMC9233667 DOI: 10.1038/s41467-022-31308-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 06/14/2022] [Indexed: 11/23/2022] Open
Abstract
Fungal infections cause more than 1.5 million deaths annually. With an increase in immune-deficient susceptible populations and the emergence of antifungal drug resistance, there is an urgent need for novel strategies to combat these life-threatening infections. Here, we use a combinatorial screening approach to identify an imidazopyrazoindole, NPD827, that synergizes with fluconazole against azole-sensitive and -resistant isolates of Candida albicans. NPD827 interacts with sterols, resulting in profound effects on fungal membrane homeostasis and induction of membrane-associated stress responses. The compound impairs virulence in a Caenorhabditis elegans model of candidiasis, blocks C. albicans filamentation in vitro, and prevents biofilm formation in a rat model of catheter infection by C. albicans. Collectively, this work identifies an imidazopyrazoindole scaffold with a non-protein-targeted mode of action that re-sensitizes the leading human fungal pathogen, C. albicans, to azole antifungals.
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Affiliation(s)
- Nicole M Revie
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Kali R Iyer
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Michelle E Maxson
- Program in Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Jiabao Zhang
- Department of Chemistry, Roger Adams Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Su Yan
- Department of Chemistry, Roger Adams Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Caroline M Fernandes
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA
| | - Kirsten J Meyer
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Xuefei Chen
- David Braley Centre for Antibiotics Discovery, M.G. DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Iwona Skulska
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Meea Fogal
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Hiram Sanchez
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, USA
| | - Saif Hossain
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Sheena Li
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular Research, Toronto, ON, Canada
| | - Yoko Yashiroda
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
| | - Hiroyuki Hirano
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
| | - Minoru Yoshida
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
- Department of Biotechnology, Graduate School of Agricultural Life Sciences, The University of Tokyo, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Osada
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
| | - Charles Boone
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular Research, Toronto, ON, Canada
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - David R Andes
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, USA
| | - Gerard D Wright
- David Braley Centre for Antibiotics Discovery, M.G. DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Justin R Nodwell
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA
- Division of Infectious Diseases, Stony Brook University, Stony Brook, NY, USA
- Veteran Administration Medical Center, Northport, NY, USA
| | - Martin D Burke
- Department of Chemistry, Roger Adams Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Biochemistry, Roger Adams Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.
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3
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Khadka NK, Mortimer MF, Marosvari M, Timsina R, Mainali L. Membrane elasticity modulated by cholesterol in model of porcine eye lens-lipid membrane. Exp Eye Res 2022; 220:109131. [PMID: 35636489 PMCID: PMC10131281 DOI: 10.1016/j.exer.2022.109131] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 05/08/2022] [Accepted: 05/22/2022] [Indexed: 11/29/2022]
Abstract
Experimental evidence shows that the eye lens loses its elasticity dramatically with age. It has also been reported that the cholesterol (Chol) content in the eye lens fiber cell plasma membrane increases significantly with age. High Chol content leads to the formation of cholesterol bilayer domains (CBDs) in the lens membrane. The role of high Chol associated with lens elasticity is unclear. The purpose of this research is to investigate the membrane elasticity of the model of porcine lens-lipid (MPLL) membrane with increasing Chol content to elucidate the role of high Chol in lens membrane elasticity. In this study, we used atomic force microscopy (AFM) to study the mechanical properties (breakthrough force and area compressibility modulus (KA)) of the MPLL membrane with increasing Chol content where KA is the measure of membrane elasticity. We varied Chol concentration in Chol/MPLL membrane from 0 to ∼71 mol%. Supported Chol/MPLL membranes were prepared by fusion of small unilamellar vesicles (SUVs) on top of a flat mica surface. SUVs of the Chol/MPLL lipid mixture were prepared with the rapid solvent exchange method followed by probe-tip sonication. For the Chol/MPLL mixing ratio of 0, AFM image showed the formation of two distinct phases of the membrane, i.e., liquid-disordered phase (ld) and solid-ordered phase (so) membrane. However, with Chol/MPLL mixing ratio of 0.5 and above, only liquid-ordered phase (lo) membrane was formed. Also, two distinct breakthrough forces corresponding to ld and so were observed for Chol/MPLL mixing ratio of 0, whereas only one breakthrough force was observed for membranes with Chol/MPLL mixing ratio of 0.5 and above. No significant difference in the membrane surface roughness was measured with increasing Chol content for these membranes; however, breakthrough force and KA for lo membrane increased when Chol/MPLL mixing ratio was increased from 0.5 to 1. Interestingly above the Chol/MPLL mixing ratio of 1, both breakthrough force and KA decreased, indicating the formation of CBDs. Furthermore, these results showed that membrane elasticity increases at high Chol content, suggesting that high Chol content in lens membrane might be responsible for maintaining lens membrane elasticity.
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Affiliation(s)
- Nawal K Khadka
- Department of Physics, Boise State University, Boise, ID, USA
| | | | - Mason Marosvari
- Department of Physics, Boise State University, Boise, ID, USA
| | - Raju Timsina
- Department of Physics, Boise State University, Boise, ID, USA
| | - Laxman Mainali
- Department of Physics, Boise State University, Boise, ID, USA; Biomolecular Sciences Graduate Program, Boise State University, Boise, ID, USA.
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4
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Platelet Membrane: An Outstanding Factor in Cancer Metastasis. MEMBRANES 2022; 12:membranes12020182. [PMID: 35207103 PMCID: PMC8875259 DOI: 10.3390/membranes12020182] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/27/2022] [Accepted: 01/31/2022] [Indexed: 12/02/2022]
Abstract
In addition to being biological barriers where the internalization or release of biomolecules is decided, cell membranes are contact structures between the interior and exterior of the cell. Here, the processes of cell signaling mediated by receptors, ions, hormones, cytokines, enzymes, growth factors, extracellular matrix (ECM), and vesicles begin. They triggering several responses from the cell membrane that include rearranging its components according to the immediate needs of the cell, for example, in the membrane of platelets, the formation of filopodia and lamellipodia as a tissue repair response. In cancer, the cancer cells must adapt to the new tumor microenvironment (TME) and acquire capacities in the cell membrane to transform their shape, such as in the case of epithelial−mesenchymal transition (EMT) in the metastatic process. The cancer cells must also attract allies in this challenging process, such as platelets, fibroblasts associated with cancer (CAF), stromal cells, adipocytes, and the extracellular matrix itself, which limits tumor growth. The platelets are enucleated cells with fairly interesting growth factors, proangiogenic factors, cytokines, mRNA, and proteins, which support the development of a tumor microenvironment and support the metastatic process. This review will discuss the different actions that platelet membranes and cancer cell membranes carry out during their relationship in the tumor microenvironment and metastasis.
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5
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Tai P, Golding M, Singh H, Everett D. The bovine milk fat globule membrane – Liquid ordered domain formation and anticholesteremic effects during digestion. FOOD REVIEWS INTERNATIONAL 2022. [DOI: 10.1080/87559129.2021.2015773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Patrick Tai
- Riddet Institute, Palmerston North, New Zealand
- School of Food and Advanced Technology, Massey University, Palmerston North, New Zealand
| | - Matt Golding
- Riddet Institute, Palmerston North, New Zealand
- School of Food and Advanced Technology, Massey University, Palmerston North, New Zealand
| | | | - David Everett
- Riddet Institute, Palmerston North, New Zealand
- Grasslands Research Centre, AgResearch, Palmerston North, New Zealand
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6
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Siani P, Donadoni E, Ferraro L, Re F, Di Valentin C. Molecular dynamics simulations of doxorubicin in sphingomyelin-based lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1864:183763. [PMID: 34506799 DOI: 10.1016/j.bbamem.2021.183763] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/22/2021] [Accepted: 08/26/2021] [Indexed: 12/14/2022]
Abstract
Doxorubicin (DOX) is one of the most efficient antitumor drugs employed in numerous cancer therapies. Its incorporation into lipid-based nanocarriers, such as liposomes, improves the drug targeting into tumor cells and reduces drug side effects. The carriers' lipid composition is expected to affect the interactions of DOX and its partitioning into liposomal membranes. To get a rational insight into this aspect and determine promising lipid compositions, we use numerical simulations, which provide unique information on DOX-membrane interactions at the atomic level of resolution. In particular, we combine classical molecular dynamics simulations and free energy calculations to elucidate the mechanism of penetration of a protonated Doxorubicin molecule (DOX+) into potential liposome membranes, here modeled as lipid bilayers based on mixtures of phosphatidylcholine (PC), sphingomyelin (SM) and cholesterol lipid molecules, of different compositions and lipid phases. Moreover, we analyze DOX+ partitioning into relevant regions of SM-based lipid bilayer systems using a combination of free energy methods. Our results show that DOX+ penetration and partitioning are facilitated into less tightly packed SM-based membranes and are dependent on lipid composition. This work paves the way to further investigations of optimal formulations for lipid-based carriers, such as those associated with pH-responsive membranes.
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Affiliation(s)
- Paulo Siani
- Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Edoardo Donadoni
- Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Lorenzo Ferraro
- Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Francesca Re
- School of Medicine and Surgery, University of Milano-Bicocca, via Raoul Follereau 3, Vedano al Lambro, MB 20854, Italy; BioNanoMedicine Center NANOMIB, University of Milano-Bicocca, Italy
| | - Cristiana Di Valentin
- Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy; BioNanoMedicine Center NANOMIB, University of Milano-Bicocca, Italy.
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7
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Dingjan T, Futerman AH. The role of the 'sphingoid motif' in shaping the molecular interactions of sphingolipids in biomembranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183701. [PMID: 34302797 DOI: 10.1016/j.bbamem.2021.183701] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 07/16/2021] [Indexed: 12/28/2022]
Abstract
Sphingolipids can be differentiated from other membrane lipids by the distinctive chemistry of the sphingoid long chain base (LCB), which is generated by the condensation of an amino acid (normally but not always serine) and a fatty acyl CoA (normally palmitoyl CoA) by the pyridoxal phosphate-dependent enzyme, serine palmitoyl transferase (SPT). The first five carbon atoms of the sphingoid LCB, herein defined as the 'sphingoid motif', are largely responsible for the unique chemical and biophysical properties of sphingolipids since they can undergo a relatively large number (compared to other lipid species) of molecular interactions with other membrane lipids, via hydrogen-bonding, charge-pairing, hydrophobic and van der Waals interactions. These interactions are responsible, for instance, for the association of sphingolipids with cholesterol in the membrane lipid bilayer. Here, we discuss some of the unique properties of this sphingoid motif, and in addition to outlining how this structural motif drives intra-bilayer interactions, discuss the atomic details of the interactions with two critical players in the biosynthetic pathway, namely SPT, and the ceramide transport protein, CERT. In the former, the selectivity of sphingolipid synthesis relies on a hydrogen bond interaction between Lys379 of SPTLC2 and the l-serine sidechain hydroxyl moiety. In the latter, the entire sphingoid motif is stereoselectively recognized by a hydrogen-bonding network involving all three sphingoid motif heteroatoms. The remarkable selectivity of these interactions, and the subtle means by which these interactions are modified and regulated in eukaryotic cells raises a number of challenging questions about the generation of these proteins, and of their interactions with the sphingoid motif in evolutionary history.
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Affiliation(s)
- Tamir Dingjan
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Anthony H Futerman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
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8
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Lange Y, Steck TL. Active cholesterol 20 years on. Traffic 2020; 21:662-674. [PMID: 32930466 DOI: 10.1111/tra.12762] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 12/13/2022]
Abstract
This review considers the following hypotheses, some well-supported and some speculative. Almost all of the sterol molecules in plasma membranes are associated with bilayer phospholipids in complexes of varied strength and stoichiometry. These complexes underlie many of the material properties of the bilayer. The small fraction of cholesterol molecules exceeding the binding capacity of the phospholipids is thermodynamically active and serves diverse functions. It circulates briskly among the cell membranes, particularly through contact sites linking the organelles. Active cholesterol provides the upstream feedback signal to multiple mechanisms governing plasma membrane homeostasis, pegging the sterol level to a threshold set by its phospholipids. Active cholesterol could also be the cargo for various inter-organelle transporters and the form excreted from cells by reverse transport. Furthermore, it is integral to the function of caveolae; a mediator of Hedgehog regulation; and a ligand for the binding of cytolytic toxins to membranes. Active cholesterol modulates a variety of plasma membrane proteins-receptors, channels and transporters-at least in vitro.
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Affiliation(s)
- Yvonne Lange
- Department of Pathology, Rush University Medical Center, Chicago, Illinois, USA
| | - Theodore L Steck
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
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9
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Vahedi A, Bigdelou P, Farnoud AM. Quantitative analysis of red blood cell membrane phospholipids and modulation of cell-macrophage interactions using cyclodextrins. Sci Rep 2020; 10:15111. [PMID: 32934292 PMCID: PMC7492248 DOI: 10.1038/s41598-020-72176-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 08/21/2020] [Indexed: 01/27/2023] Open
Abstract
The plasma membrane of eukaryotic cells is asymmetric with respect to its phospholipid composition. Analysis of the lipid composition of the outer leaflet is important for understanding cell membrane biology in health and disease. Here, a method based on cyclodextrin-mediated lipid exchange to characterize the phospholipids in the outer leaflet of red blood cells (RBCs) is reported. Methyl-α-cyclodextrin, loaded with exogenous lipids, was used to extract phospholipids from the membrane outer leaflet, while delivering lipids to the cell to maintain cell membrane integrity. Thin layer chromatography and lipidomics demonstrated that the extracted lipids were from the membrane outer leaflet. Phosphatidylcholines (PC) and sphingomyelins (SM) were the most abundant phospholipids in the RBCs outer leaflet with PC 34:1 and SM 34:1 being the most abundant species. Fluorescence quenching confirmed the delivery of exogenous lipids to the cell outer leaflet. The developed lipid exchange method was then used to remove phosphatidylserine, a phagocyte recognition marker, from the outer leaflet of senescent RBCs. Senescent RBCs with reconstituted membranes were phagocytosed in significantly lower amounts compared to control cells, demonstrating the efficiency of the lipid exchange process and its application in modifying cell–cell interactions.
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Affiliation(s)
- Amid Vahedi
- Department of Chemical and Biomolecular Engineering, Ohio University, 161 Stocker Center, Athens, OH, 45701, USA
| | - Parnian Bigdelou
- Biomedical Engineering Program, Ohio University, Athens, OH, 45701, USA
| | - Amir M Farnoud
- Department of Chemical and Biomolecular Engineering, Ohio University, 161 Stocker Center, Athens, OH, 45701, USA. .,Biomedical Engineering Program, Ohio University, Athens, OH, 45701, USA.
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10
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Kumari P, Kumari M, Kashyap HK. Counter-effects of Ethanol and Cholesterol on the Heterogeneous PSM–POPC Lipid Membrane: A Molecular Dynamics Simulation Study. J Phys Chem B 2019; 123:9616-9628. [DOI: 10.1021/acs.jpcb.9b07107] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Pratibha Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Monika Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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11
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Nyholm TKM, Engberg O, Hautala V, Tsuchikawa H, Lin KL, Murata M, Slotte JP. Impact of Acyl Chain Mismatch on the Formation and Properties of Sphingomyelin-Cholesterol Domains. Biophys J 2019; 117:1577-1588. [PMID: 31610877 DOI: 10.1016/j.bpj.2019.09.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 11/30/2022] Open
Abstract
Lateral segregation and the formation of lateral domains are well-known phenomena in ternary lipid bilayers composed of an unsaturated (low gel-to-liquid phase transition temperature (Tm)) phospholipid, a saturated (high-Tm) phospholipid, and cholesterol. The formation of lateral domains has been shown to be influenced by differences in phospholipid acyl chain unsaturation and length. Recently, we also showed that differential interactions of cholesterol with low- and high-Tm phospholipids in the bilayer can facilitate phospholipid segregation. Now, we have investigated phospholipid-cholesterol interactions and their role in lateral segregation in ternary bilayers composed of different unsaturated phosphatidylcholines (PCs) with varying acyl chain lengths, N-palmitoyl-D-erythro-sphingomyelin (PSM), and cholesterol. Using deuterium NMR spectroscopy, we determined how PSM was influenced by the acyl chain composition in surrounding PC environments and correlated this with the affinity of cholestatrienol (a fluorescent cholesterol analog) for PSM in the different PC environments. Results from a combination of time-resolved fluorescence measurements of trans-parinaric acid and Förster resonance energy transfer experiments showed that the relative affinity of cholesterol for phospholipids determined the degree to which the sterol promoted domain formation. From Förster resonance energy transfer, deuterium NMR, and differential scanning calorimetry results, it was clear that cholesterol also influenced both the thermostability of the domains and the degree of order in and outside the PSM-rich domains. The results of this study have shown that the affinity of cholesterol for both low-Tm and high-Tm phospholipids and the effects of low- and high-Tm phospholipids on each other influence both lateral structure and domain properties in complex bilayers. We envision that similar effects also contribute to lateral heterogeneity in even more complex biological membranes.
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Affiliation(s)
- Thomas K M Nyholm
- Biochemistry, Faculty of Science and Engineering, Abo Akademi University, Turku Finland.
| | - Oskar Engberg
- Biochemistry, Faculty of Science and Engineering, Abo Akademi University, Turku Finland
| | - Victor Hautala
- Biochemistry, Faculty of Science and Engineering, Abo Akademi University, Turku Finland
| | - Hiroshi Tsuchikawa
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
| | - Kai-Lan Lin
- Biochemistry, Faculty of Science and Engineering, Abo Akademi University, Turku Finland
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
| | - J Peter Slotte
- Biochemistry, Faculty of Science and Engineering, Abo Akademi University, Turku Finland
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12
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Laurent N, Der C, Simon-Plas F, Gerbeau-Pissot P. Cell stage appears critical for control of plasma membrane order in plant cells. PLANT SIGNALING & BEHAVIOR 2019; 14:1620058. [PMID: 31131686 PMCID: PMC6619956 DOI: 10.1080/15592324.2019.1620058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/07/2019] [Accepted: 05/10/2019] [Indexed: 05/26/2023]
Abstract
Lipids and proteins modulate both the global order of plasma membrane (PM) and its organization in distinct domains. This raises the question of the influence on PM-ordered domain formation of PM composition, which is finely controlled during cell differentiation. Labeling of plant cell PM with an environment-sensitive probe demonstrated that the level of PM order is regulated during anisotropic expansion observed during both cell regeneration from protoplasts and cell differentiation along the growing root. Indeed, PM order progressively decreased during the polarized growth of regenerated tobacco cells, without observed correlation between this parameter and the kinetics of either cell wall regeneration or cell morphology. This suggests that the dynamics of PM formation and renewal could control the PM organization, maybe by involving the secretory pathway.
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Affiliation(s)
- Nelson Laurent
- Agroécologie, AgroSup Dijon, CNRS, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Christophe Der
- Agroécologie, AgroSup Dijon, CNRS, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Françoise Simon-Plas
- Agroécologie, AgroSup Dijon, CNRS, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Patricia Gerbeau-Pissot
- Agroécologie, AgroSup Dijon, CNRS, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
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13
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Enkavi G, Javanainen M, Kulig W, Róg T, Vattulainen I. Multiscale Simulations of Biological Membranes: The Challenge To Understand Biological Phenomena in a Living Substance. Chem Rev 2019; 119:5607-5774. [PMID: 30859819 PMCID: PMC6727218 DOI: 10.1021/acs.chemrev.8b00538] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Indexed: 12/23/2022]
Abstract
Biological membranes are tricky to investigate. They are complex in terms of molecular composition and structure, functional over a wide range of time scales, and characterized by nonequilibrium conditions. Because of all of these features, simulations are a great technique to study biomembrane behavior. A significant part of the functional processes in biological membranes takes place at the molecular level; thus computer simulations are the method of choice to explore how their properties emerge from specific molecular features and how the interplay among the numerous molecules gives rise to function over spatial and time scales larger than the molecular ones. In this review, we focus on this broad theme. We discuss the current state-of-the-art of biomembrane simulations that, until now, have largely focused on a rather narrow picture of the complexity of the membranes. Given this, we also discuss the challenges that we should unravel in the foreseeable future. Numerous features such as the actin-cytoskeleton network, the glycocalyx network, and nonequilibrium transport under ATP-driven conditions have so far received very little attention; however, the potential of simulations to solve them would be exceptionally high. A major milestone for this research would be that one day we could say that computer simulations genuinely research biological membranes, not just lipid bilayers.
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Affiliation(s)
- Giray Enkavi
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Matti Javanainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy
of Sciences, Flemingovo naḿesti 542/2, 16610 Prague, Czech Republic
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Waldemar Kulig
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Tomasz Róg
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Ilpo Vattulainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
- MEMPHYS-Center
for Biomembrane Physics
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14
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Istvan ES, Das S, Bhatnagar S, Beck JR, Owen E, Llinas M, Ganesan SM, Niles JC, Winzeler E, Vaidya AB, Goldberg DE. Plasmodium Niemann-Pick type C1-related protein is a druggable target required for parasite membrane homeostasis. eLife 2019; 8:40529. [PMID: 30888318 PMCID: PMC6424564 DOI: 10.7554/elife.40529] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 02/05/2019] [Indexed: 01/05/2023] Open
Abstract
Plasmodium parasites possess a protein with homology to Niemann-Pick Type C1 proteins (Niemann-Pick Type C1-Related protein, NCR1). We isolated parasites with resistance-conferring mutations in Plasmodium falciparum NCR1 (PfNCR1) during selections with three diverse small-molecule antimalarial compounds and show that the mutations are causative for compound resistance. PfNCR1 protein knockdown results in severely attenuated growth and confers hypersensitivity to the compounds. Compound treatment or protein knockdown leads to increased sensitivity of the parasite plasma membrane (PPM) to the amphipathic glycoside saponin and engenders digestive vacuoles (DVs) that are small and malformed. Immuno-electron microscopy and split-GFP experiments localize PfNCR1 to the PPM. Our experiments show that PfNCR1 activity is critically important for the composition of the PPM and is required for DV biogenesis, suggesting PfNCR1 as a novel antimalarial drug target. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
- Eva S Istvan
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Sudipta Das
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Suyash Bhatnagar
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Josh R Beck
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Edward Owen
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, United States.,Huck Center for Malaria Research, Pennsylvania State University, University Park, United States.,Department of Chemistry, Pennsylvania State University, University Park, United States
| | - Manuel Llinas
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, United States.,Huck Center for Malaria Research, Pennsylvania State University, University Park, United States.,Department of Chemistry, Pennsylvania State University, University Park, United States
| | - Suresh M Ganesan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Elizabeth Winzeler
- Department of Pediatrics, University of California San Diego School of Medicine, La Jolla, United States
| | - Akhil B Vaidya
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Daniel E Goldberg
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
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15
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Ausili A, Martínez-Valera P, Torrecillas A, Gómez-Murcia V, de Godos AM, Corbalán-García S, Teruel JA, Gómez Fernández JC. Anticancer Agent Edelfosine Exhibits a High Affinity for Cholesterol and Disorganizes Liquid-Ordered Membrane Structures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:8333-8346. [PMID: 29924618 DOI: 10.1021/acs.langmuir.8b01539] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Edelfosine is an anticancer drug with an asymmetric structure because, being a derivative of glycerol, it possesses two hydrophobic substituents of very different lengths. We showed that edelfosine destabilizes liquid-ordered membranes formed by either 1-palmitoyl-2-oleoyl- sn-glycero-3-phosphocholine, sphingomyelin (SM), and cholesterol (1:1:1 molar ratio) or SM and cholesterol (2:1 molar ratio). This was observed by differential scanning calorimetry in which phase transition arises from either of these membrane systems after the addition of edelfosine. The alteration in the liquid-ordered domains was characterized by using a small-angle X-ray diffraction that revealed the formation of gel phases as a consequence of the addition of edelfosine at low temperatures and by a wide-angle X-ray diffraction that confirmed changes in the membranes, indicating the formation of these gel phases. The increase in phase transition derived by the edelfosine addition was further confirmed by Fourier-transform infrared spectroscopy. The effect of edelfosine was compared with that of structurally analogue lipids: platelet-activating factor and 1-palmitoyl-2-acetyl- sn-glycero-3-phosphocholine, which also have the capacity of destabilizing liquid-ordered domains, although they are less potent than edelfosine for this activity, and lysophosphatidylcholine, which lacks this capacity. It was concluded that edelfosine may be associated with cholesterol favorably competing with sphingomyelin, and that this sets sphingomyelin free to undergo a phase transition. Finally, the experimental observations can be described by molecular dynamics calculations in terms of intermolecular interaction energies in phospholipid-cholesterol membranes. Higher interaction energies between asymmetric phospholipids and cholesterol than between sphingomyelin and cholesterol were obtained. These results are interesting because they biophysically characterize one of the main molecular mechanisms to trigger apoptosis of the cancer cells.
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Affiliation(s)
- Alessio Ausili
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Pablo Martínez-Valera
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Alejandro Torrecillas
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Victoria Gómez-Murcia
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Ana M de Godos
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Senena Corbalán-García
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - José A Teruel
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
| | - Juan C Gómez Fernández
- Departamento de Bioquímica y Biología Molecular "A", Facultad de Veterinaria, Regional Campus of International Excellence "Campus Mare Nostrum" , Universidad de Murcia , Apartado de Correos 4021 , E-30080 Murcia , Spain
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16
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Cyclosporin A distribution in cholesterol-sphingomyelin artificial membranes modeled as Langmuir monolayers. Colloids Surf B Biointerfaces 2018; 166:286-294. [DOI: 10.1016/j.colsurfb.2018.03.031] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 11/18/2022]
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17
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Gianfrancesco MA, Paquot N, Piette J, Legrand-Poels S. Lipid bilayer stress in obesity-linked inflammatory and metabolic disorders. Biochem Pharmacol 2018; 153:168-183. [PMID: 29462590 DOI: 10.1016/j.bcp.2018.02.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/15/2018] [Indexed: 12/13/2022]
Abstract
The maintenance of the characteristic lipid compositions and physicochemical properties of biological membranes is essential for their proper function. Mechanisms allowing to sense and restore membrane homeostasis have been identified in prokaryotes for a long time and more recently in eukaryotes. A membrane remodeling can result from aberrant metabolism as seen in obesity. In this review, we describe how such lipid bilayer stress can account for the modulation of membrane proteins involved in the pathogenesis of obesity-linked inflammatory and metabolic disorders. We address the case of the Toll-like receptor 4 that is implicated in the obesity-related low grade inflammation and insulin resistance. The lipid raft-mediated TLR4 activation is promoted by an enrichment of the plasma membrane with saturated lipids or cholesterol increasing the lipid phase order. We discuss of the plasma membrane Na, K-ATPase that illustrates a new concept according to which direct interactions between specific residues and particular lipids determine both stability and activity of the pump in parallel with indirect effects of the lipid bilayer. The closely related sarco(endo)-plasmic Ca-ATPase embedded in the more fluid ER membrane seems to be more sensitive to a lipid bilayer stress as demonstrated by its inactivation in cholesterol-loaded macrophages or its inhibition mediated by an increased PtdCho/PtdEtn ratio in obese mice hepatocytes. Finally, we describe the model recently proposed for the activation of the conserved IRE-1 protein through alterations in the ER membrane lipid packing and thickness. Such IRE-1 activation could occur in response to abnormal lipid synthesis and membrane remodeling as observed in hepatocytes exposed to excess nutrients. Since the IRE-1/XBP1 branch also stimulates the lipid synthesis, this pathway could create a vicious cycle "lipogenesis-ER lipid bilayer stress-lipogenesis" amplifying hepatic ER pathology and the obesity-linked systemic metabolic defects.
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Affiliation(s)
- Marco A Gianfrancesco
- Laboratory of Immunometabolism and Nutrition, GIGA-I3, University of Liège, Liège, Belgium; Division of Diabetes, Nutrition and Metabolic Disorders, Department of Medicine, University Hospital of Liège, Liège, Belgium
| | - Nicolas Paquot
- Laboratory of Immunometabolism and Nutrition, GIGA-I3, University of Liège, Liège, Belgium; Division of Diabetes, Nutrition and Metabolic Disorders, Department of Medicine, University Hospital of Liège, Liège, Belgium
| | - Jacques Piette
- Laboratory of Virology and Immunology, GIGA-Molecular Biology of Diseases, University of Liège, Liège, Belgium
| | - Sylvie Legrand-Poels
- Laboratory of Immunometabolism and Nutrition, GIGA-I3, University of Liège, Liège, Belgium; Laboratory of Virology and Immunology, GIGA-Molecular Biology of Diseases, University of Liège, Liège, Belgium.
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18
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Bera I, Klauda JB. Molecular Simulations of Mixed Lipid Bilayers with Sphingomyelin, Glycerophospholipids, and Cholesterol. J Phys Chem B 2017; 121:5197-5208. [DOI: 10.1021/acs.jpcb.7b00359] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Indrani Bera
- Department
of Chemical and Biomolecular Engineering and ‡Biophysics Program, University of Maryland, College Park, Maryland 20742, United States
| | - Jeffery B. Klauda
- Department
of Chemical and Biomolecular Engineering and ‡Biophysics Program, University of Maryland, College Park, Maryland 20742, United States
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19
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Edler E, Schulze E, Stein M. Membrane localization and dynamics of geranylgeranylated Rab5 hypervariable region. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:1335-1349. [PMID: 28455099 DOI: 10.1016/j.bbamem.2017.04.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/18/2017] [Accepted: 04/23/2017] [Indexed: 12/11/2022]
Abstract
The small GTPase Rab5 is a key regulator of endosomal trafficking processes and a marker for the early endosome. The C-terminal hypervariable region (HVR) of Rab5 is post-translationally modified at residues Cys212 and Cys213 to accommodate two geranylgeranyl anchors (C20 carbon chain length) in order to associate Rab5 with the membrane. The structural role of the HVR regarding protein-early endosome membrane recruitment is not resolved due to its high degree of flexibility and lack of crystallographic information. Here, full-atomistic and coarse-grained molecular dynamics simulations of the truncated Rab5 HVR206-215 in three model membranes of increasing complexity (pure phospholipid bilayer, ternary membrane with cholesterol, six-component early endosome) were performed. Specific electrostatic interactions between the HVR206-215 Arg209 residue and the phosphate group of the inositol ring of PI(3)P were detected. This shows that PI(3)P acts as a first contact site of protein recruitment to the early endosome. The free energy change of HVR206-215 extraction from the bilayer was largest for the physiological negatively charged membrane. 5μs coarse-grained simulations revealed an active recruitment of PI(3)P to the HVR206-215 supporting the formation of Rab5- and PI(3)P enriched signaling platforms.
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Affiliation(s)
- Eileen Edler
- Molecular Simulations and Design Group, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
| | - Eric Schulze
- Molecular Simulations and Design Group, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany; International Max Planck Research School (IMPRS) for Advanced Methods in Process and Systems Engineering, Magdeburg, Germany
| | - Matthias Stein
- Molecular Simulations and Design Group, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany.
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20
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Rodriguez-Cuenca S, Pellegrinelli V, Campbell M, Oresic M, Vidal-Puig A. Sphingolipids and glycerophospholipids - The "ying and yang" of lipotoxicity in metabolic diseases. Prog Lipid Res 2017; 66:14-29. [PMID: 28104532 DOI: 10.1016/j.plipres.2017.01.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 11/30/2016] [Accepted: 01/05/2017] [Indexed: 12/14/2022]
Abstract
Sphingolipids in general and ceramides in particular, contribute to pathophysiological mechanisms by modifying signalling and metabolic pathways. Here, we present the available evidence for a bidirectional homeostatic crosstalk between sphingolipids and glycerophospholipids, whose dysregulation contributes to lipotoxicity induced metabolic stress. The initial evidence for this crosstalk originates from simulated models designed to investigate the biophysical properties of sphingolipids in plasma membrane representations. In this review, we reinterpret some of the original findings and conceptualise them as a sort of "ying/yang" interaction model of opposed/complementary forces, which is consistent with the current knowledge of lipid homeostasis and pathophysiology. We also propose that the dysregulation of the balance between sphingolipids and glycerophospholipids results in a lipotoxic insult relevant in the pathophysiology of common metabolic diseases, typically characterised by their increased ceramide/sphingosine pools.
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Affiliation(s)
- S Rodriguez-Cuenca
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK.
| | - V Pellegrinelli
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK
| | - M Campbell
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK
| | - M Oresic
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, FI -20520 Turku, Finland
| | - A Vidal-Puig
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK; Wellcome Trust Sanger Institute, Hinxton, UK.
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21
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Wang H, Meng F. Molecular simulation study on concentration effects of rofecoxib with POPC bilayer. J Mol Graph Model 2016; 70:94-99. [DOI: 10.1016/j.jmgm.2016.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 10/21/2022]
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22
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Kim S, Chang R. Structure, Dynamics, and Phase Behavior of DOPC/DSPC Mixture Membrane Systems: Molecular Dynamics Simulation Studies. B KOREAN CHEM SOC 2016. [DOI: 10.1002/bkcs.10827] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Seonghan Kim
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| | - Rakwoo Chang
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
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23
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Sodt AJ, Pastor RW, Lyman E. Hexagonal Substructure and Hydrogen Bonding in Liquid-Ordered Phases Containing Palmitoyl Sphingomyelin. Biophys J 2016; 109:948-55. [PMID: 26331252 DOI: 10.1016/j.bpj.2015.07.036] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 07/11/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022] Open
Abstract
All-atom simulation data are presented for ternary mixtures of palmitoyl sphingomyelin (PSM), cholesterol, and either palmitoyl oleoyl phosphatidyl choline or dioleoyl phosphatidyl choline (DOPC). For comparison, data for a mixture of dipalmitoyl phosphatidyl choline (DPPC), cholesterol, and DOPC are also presented. Compositions corresponding to the liquid-ordered phase, the liquid-disordered phase, and coexistence of the two phases are simulated for each mixture. Within the liquid-ordered phase, cholesterol is preferentially solvated by DOPC if it is available, but if DOPC is replaced by POPC, cholesterol is preferentially solvated by PSM. In the DPPC mixtures, cholesterol interacts preferentially with the saturated chains via its smooth face, whereas in the PSM mixtures, cholesterol interacts preferentially with PSM via its rough face. Interactions between cholesterol and PSM have a very particular character: hydrogen bonding between cholesterol and the amide of PSM rotates the tilt of the amide plane, which primes it for more robust hydrogen bonding with other PSM. Cholesterol-PSM hydrogen bonding also locally modifies the hexagonal packing of hydrocarbon chains in the liquid-ordered phase of PSM mixtures.
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Affiliation(s)
- Alexander J Sodt
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Richard W Pastor
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Edward Lyman
- Department of Physics and Astronomy and Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware.
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24
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Lazzarini A, Macchiarulo A, Floridi A, Coletti A, Cataldi S, Codini M, Lazzarini R, Bartoccini E, Cascianelli G, Ambesi-Impiombato FS, Beccari T, Curcio F, Albi E. Very-long-chain fatty acid sphingomyelin in nuclear lipid microdomains of hepatocytes and hepatoma cells: can the exchange from C24:0 to C16:0 affect signal proteins and vitamin D receptor? Mol Biol Cell 2016; 26:2418-25. [PMID: 26124436 PMCID: PMC4571297 DOI: 10.1091/mbc.e15-04-0229] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Lipid microdomains localized in the inner nuclear membrane are considered platforms for active chromatin anchoring. Stimuli such as surgery, vitamin D, or glucocorticoid drugs influence their gene expression, DNA duplication, and RNA synthesis. In this study, we used ultrafast liquid chromatography-tandem mass spectrometry to identify sphingomyelin (SM) species coupled with immunoblot analysis to comprehensively map differences in nuclear lipid microdomains (NLMs) purified from hepatocytes and hepatoma cells. We showed that NLMs lost saturated very-long-chain fatty acid (FA; C24:0) SM in cancer cells and became enriched in long-chain FA (C16:0) SM. We also found that signaling proteins, such as STAT3, Raf1, and PKCζ, were increased and vitamin D receptor was reduced in cancer cells. Because recent researches showed a shift in sphingolipid composition from C24:0 to C16:0 in relation to cell life, we performed a comparative analysis of properties among C16:0 SM, C24:0 SM, and cholesterol. Our results led us to hypothesize that the enrichment of C16:0 SM could determine enhanced dynamic properties of NLMs in cancer cells with an increased shuttling of protein signaling molecules.
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Affiliation(s)
- Andrea Lazzarini
- Laboratory of Nuclear Lipid BioPathology, CRABiON, 06100 Perugia, Italy
| | - Antonio Macchiarulo
- Department of Pharmaceutical Science, University of Perugia, 06123 Perugia, Italy
| | | | - Alice Coletti
- Department of Pharmaceutical Science, University of Perugia, 06123 Perugia, Italy
| | - Samuela Cataldi
- Department of Pharmaceutical Science, University of Perugia, 06123 Perugia, Italy
| | - Michela Codini
- Department of Pharmaceutical Science, University of Perugia, 06123 Perugia, Italy
| | - Remo Lazzarini
- Laboratory of Nuclear Lipid BioPathology, CRABiON, 06100 Perugia, Italy
| | - Elisa Bartoccini
- Laboratory of Nuclear Lipid BioPathology, CRABiON, 06100 Perugia, Italy
| | | | | | - Tommaso Beccari
- Department of Pharmaceutical Science, University of Perugia, 06123 Perugia, Italy
| | - Francesco Curcio
- Department of Clinical and Biological Sciences, University of Udine, 33100 Udine, Italy
| | - Elisabetta Albi
- Laboratory of Nuclear Lipid BioPathology, CRABiON, 06100 Perugia, Italy
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25
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The importance of hydrogen bonding in sphingomyelin's membrane interactions with co-lipids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:304-10. [DOI: 10.1016/j.bbamem.2015.12.008] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/16/2015] [Accepted: 12/03/2015] [Indexed: 01/10/2023]
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26
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Ganesan SJ, Xu H, Matysiak S. Effect of lipid head group interactions on membrane properties and membrane-induced cationic β-hairpin folding. Phys Chem Chem Phys 2016; 18:17836-50. [DOI: 10.1039/c5cp07669b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Stages in membrane induced SVS-1 folding.
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Affiliation(s)
- Sai J. Ganesan
- Fischell Department of Bioengineering
- University of Maryland
- College Park
- USA
| | - Hongcheng Xu
- Biophysics Program
- University of Maryland
- College Park
- USA
| | - Silvina Matysiak
- Fischell Department of Bioengineering
- University of Maryland
- College Park
- USA
- Biophysics Program
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27
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Mevalonate inhibits acid sphingomyelinase activity, increases sphingomyelin levels and inhibits cell proliferation of HepG2 and Caco-2 cells. Lipids Health Dis 2015; 14:130. [PMID: 26493087 PMCID: PMC4618740 DOI: 10.1186/s12944-015-0137-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 10/15/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Sphingomyelin (SM) and cholesterol are two types of lipid closely related biophysically. Treating the cells with exogenous sphingomyelinase (SMase) induces trafficking of cholesterol from membrane to intracellular pools and inhibition of cholesterol synthesis. In the present work, we address a question whether increased cholesterol synthesis affects hydrolysis of SM by endogenous SMases. METHODS Both HepG2 and Caco-2 cells were incubated with mevalonate. The SMase activity was determined and its mRNA examined by qPCR. The cellular levels of cholesterol, SM, and phosphatidylcholine (PC) were determined and cell proliferation rate assayed. RESULTS We found that mevalonate dose-dependently decreased acid but not neutral SMase activity in both HepG2 and Caco-2 cells with HepG2 cells being more sensitive to mevalonate. Kinetic examination in HepG2 cells revealed that acid SMase activity was increasing with cell proliferation, and such an increase was reversed by mevalonate treatment. Acid SMase mRNA was not significantly decreased and Western blot showed signs of proteolysis of acid SMase by mevalonate. After mevalonate treatment, the levels of cholesterol were significantly increased associated with increases in SM and PC. The cell growth was retarded by mevalonate and the effect was more obvious in HepG2 cells than in Caco-2 cells. CONCLUSION Mevalonate can trigger a mechanism to enhance SM levels by inhibition of acid SMase. The effect may ensure the coordinate changes of SM and cholesterol in the cells. Mevalonate also affects cell growth with mechanism required further characterization.
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Jurak M, Golabek M, Holysz L, Chibowski E. Properties of Langmuir and solid supported lipid films with sphingomyelin. Adv Colloid Interface Sci 2015; 222:385-97. [PMID: 24725646 DOI: 10.1016/j.cis.2014.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/19/2014] [Accepted: 03/20/2014] [Indexed: 12/11/2022]
Abstract
Biological cell membranes play a crucial role in various biological processes and their functionality to some extent is determined by the hydrophilic/hydrophobic balance. A significant progress in understanding the membrane structure was the discovery of laterally segregated lipid domains, called the lipid rafts. These raft domains are of ordered lamellar liquid-crystalline phase, while rest of the membrane exists in a relatively disordered lamellar liquid-crystalline phase. Moreover, the chemical constitution of the lipid rafts consists of a higher content (up to 50%) of cholesterol (Chol) and sphingomyelin (SM). Sphingomyelin also plays a significant role in the red cells of blood and nerves, in some diseases, as a precursor to ceramides, and other sphingolipid metabolites. In this paper properties of Langmuir and solid supported mixed lipid films of DPPC/SM, DOPC/SM, and Chol/SM are described. Special attention has been paid to wetting properties (hydrophobic/hydrophilic balance) of these films transferred onto a hydrophilic glass surface. To our knowledge such results have not yet been published in the literature. The properties were determined via contact angle measurements and then calculation of the films' apparent surface free energy. The films' wettability and their apparent surface free energy strongly depend on their composition. The energy is affected by both the structure of hydrocarbon chains of glycerophospholipids (DPPC and DOPC) and their interactions with SM. Properties of mixed Chol/SM monolayer depend also on the film stoichiometry. At a low Chol content (XChol=0.25) the interactions between SM and Chol are strong and hence the formation of binary complex is possible. This is accompanied by a decrease in the film surface free energy in comparison to that of pure SM monolayer, contrary to a higher Chol content where the monolayer energy increases. This suggests that cholesterol is excluded from the membrane thus increasing the film hydrophilicity. These results are consistent with the literature data and somehow confirm the hypothesis of lipid raft formation. The roughness of the investigated monolayer surfaces was also determined using optical profilometry. The roughness parameters of the DPPC, SM, and mixed DPPC/SM generally correlate with the changes of their apparent surface free energy, i.e. with the decreasing roughness the apparent surface free energy also decreases. However, this is not the case for mixed DOPC/SM monolayers. Although the roughness increases with SM content the apparent surface free energy decreases. Therefore some other factors, like the presence of unsaturated bonds in the DOPC molecule, influence the film phase state and the energy too. More experiments are needed to explain this hypothesis.
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Kulig W, Olżyńska A, Jurkiewicz P, Kantola AM, Komulainen S, Manna M, Pourmousa M, Vazdar M, Cwiklik L, Rog T, Khelashvili G, Harries D, Telkki VV, Hof M, Vattulainen I, Jungwirth P. Cholesterol under oxidative stress-How lipid membranes sense oxidation as cholesterol is being replaced by oxysterols. Free Radic Biol Med 2015; 84:30-41. [PMID: 25795515 DOI: 10.1016/j.freeradbiomed.2015.03.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 03/06/2015] [Accepted: 03/09/2015] [Indexed: 02/06/2023]
Abstract
The behavior of oxysterols in phospholipid membranes and their effects on membrane properties were investigated by means of dynamic light scattering, fluorescence spectroscopy, NMR, and extensive atomistic simulations. Two families of oxysterols were scrutinized-tail-oxidized sterols, which are mostly produced by enzymatic processes, and ring-oxidized sterols, formed mostly via reactions with free radicals. The former family of sterols was found to behave similar to cholesterol in terms of molecular orientation, roughly parallel to the bilayer normal, leading to increasing membrane stiffness and suppression of its membrane permeability. In contrast, ring-oxidized sterols behave quantitatively differently from cholesterol. They acquire tilted orientations and therefore disrupt the bilayer structure with potential implications for signaling and other biochemical processes in the membranes.
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Affiliation(s)
- Waldemar Kulig
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
| | - Agnieszka Olżyńska
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Piotr Jurkiewicz
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic.
| | - Anu M Kantola
- Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland
| | - Sanna Komulainen
- Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland
| | - Moutusi Manna
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Mohsen Pourmousa
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Mario Vazdar
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland; Rudjer Bošković Institute, Division of Organic Chemistry and Biochemistry, POB 180, HR-10002 Zagreb, Croatia
| | - Lukasz Cwiklik
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic; Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic.
| | - Tomasz Rog
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | | | - Daniel Harries
- Institute of Chemistry and the Fritz Haber Research Center, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ville-Veikko Telkki
- Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic; Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
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Vogel A, Nikolaus J, Weise K, Triola G, Waldmann H, Winter R, Herrmann A, Huster D. Interaction of the human N-Ras protein with lipid raft model membranes of varying degrees of complexity. Biol Chem 2015; 395:779-89. [PMID: 24526608 DOI: 10.1515/hsz-2013-0294] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/06/2014] [Indexed: 11/15/2022]
Abstract
Ternary lipid mixtures composed of cholesterol, saturated (frequently with sphingosine backbone), and unsaturated phospholipids show stable phase separation and are often used as model systems of lipid rafts. Yet, their ability to reproduce raft properties and function is still debated. We investigated the properties and functional aspects of three lipid raft model systems of varying degrees of biological relevance--PSM/POPC/Chol, DPPC/POPC/Chol, and DPPC/DOPC/Chol--using 2H solid-state nuclear magnetic resonance (NMR) spectroscopy, fluorescence microscopy, and atomic force microscopy. While some minor differences were observed, the general behavior and properties of all three model mixtures were similar to previously investigated influenza envelope lipid membranes, which closely mimic the lipid composition of biological membranes. For the investigation of the functional aspects, we employed the human N-Ras protein, which is posttranslationally modified by two lipid modifications that anchor the protein to the membrane. It was previously shown that N-Ras preferentially resides in liquid-disordered domains and exhibits a time-dependent accumulation in the domain boundaries of influenza envelope lipid membranes. For all three model mixtures, we observed the same membrane partitioning behavior for N-Ras. Therefore, we conclude that even relatively simple models of raft membranes are able to reproduce many of their specific properties and functions.
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31
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Pezeshkian W, Chaban VV, Johannes L, Shillcock J, Ipsen JH, Khandelia H. The effects of globotriaosylceramide tail saturation level on bilayer phases. SOFT MATTER 2015; 11:1352-1361. [PMID: 25575293 DOI: 10.1039/c4sm02456g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Globotriaosylceramide (Gb3) is a glycosphingolipid present in the plasma membrane that is the natural receptor of the bacterial Shiga toxin. The unsaturation level of Gb3 acyl chains has a drastic impact on lipid bilayer properties and phase behaviour, and on many Gb3-related cellular processes. For example: the Shiga toxin B subunit forms tubular invaginations in the presence of Gb3 with an unsaturated acyl chain (U-Gb3), while in the presence of Gb3 with a saturated acyl chain (S-Gb3) such invagination does not occur. We have used all-atom molecular dynamics simulations to investigate the effects of the Gb3 concentration and its acyl chain saturation on the phase behaviour of a mixed bilayer of dioleoylphosphatidylcholine and Gb3. The simulation results show that: (1) the Gb3 acyl chains (longer tails) from one leaflet interdigitate into the opposing leaflet and lead to significant bilayer rigidification and immobilisation of the lipid tails. S-Gb3 can form a highly ordered, relatively immobile phase which is resistant to bending while these changes for U-Gb3 are not significant. (2) At low concentrations of Gb3, U-Gb3 and S-Gb3 have a similar impact on the bilayer reminiscent of the effect of sphingomyelin lipids and (3) At higher Gb3 concentrations, U-Gb3 mixes better with dioleoylphosphatidylcholine than S-Gb3. Our simulations also provide the first molecular level structural model of Gb3 in membranes.
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Affiliation(s)
- Weria Pezeshkian
- Center for Biomembrane Physics (MEMPHYS), Department of Physics, Chemistry and Pharmacy (FKF), University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.
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Ferraro M, Masetti M, Recanatini M, Cavalli A, Bottegoni G. Modeling lipid raft domains containing a mono-unsaturated phosphatidylethanolamine species. RSC Adv 2015. [DOI: 10.1039/c5ra02196k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
An advanced coarse-grained model for “atypical” lipid rafts was built and validated to be employed in studies of membrane-protein interactions.
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Affiliation(s)
- M. Ferraro
- D3 Compunet
- Istituto Italiano di Tecnologia
- Genova
- Italy
| | - M. Masetti
- Department of Pharmacy and Biotechnology
- Alma Mater Studiorum – Università di Bologna
- Bologna
- Italy
| | - M. Recanatini
- Department of Pharmacy and Biotechnology
- Alma Mater Studiorum – Università di Bologna
- Bologna
- Italy
| | - A. Cavalli
- D3 Compunet
- Istituto Italiano di Tecnologia
- Genova
- Italy
- Department of Pharmacy and Biotechnology
| | - G. Bottegoni
- D3 Compunet
- Istituto Italiano di Tecnologia
- Genova
- Italy
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33
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Alm I, García-Linares S, Gavilanes JG, Martínez-Del-Pozo Á, Slotte JP. Cholesterol stimulates and ceramide inhibits Sticholysin II-induced pore formation in complex bilayer membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:925-31. [PMID: 25546840 DOI: 10.1016/j.bbamem.2014.12.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/11/2014] [Accepted: 12/18/2014] [Indexed: 12/14/2022]
Abstract
The pore forming capacity of Sticholysin II (StnII; isolated from Stichodactyla helianthus) in bilayer membranes containing 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), palmitoylsphingomyelin (PSM) and either cholesterol or palmitoyl ceramide (PCer) has been examined. The aim of the study was to elucidate how the presence of differently ordered PSM domains affected StnII oligomerization and pore formation. Cholesterol is known to enhance pore formation by StnII, and our results confirmed this and provide kinetic information for the process. The effect of cholesterol on bilayer permeabilization kinetics was concentration-dependent. In the concentration regime used (2.5-10nmol cholesterol in POPC:PSM 80:20 by nmol), cholesterol also increased the acyl chain order in the fluid PSM domain and thus decreased bilayer fluidity, suggesting that fluidity per se was not responsible for cholesterol's effect. Addition of PCer (2.5-10nmol) to the POPC:PSM (80:20 by nmol) bilayers attenuated StnII-induced pore formation, again in a concentration-dependent fashion. This addition also led to the formation of a PCer-rich gel phase. Addition of cholesterol to PCer-containing membranes could partially reduce the inhibitory effect of PCer on StnII pore formation. We conclude that the physical state of PSM (as influenced by either cholesterol or PCer) affected StnII binding and pore formation under the conditions examined.
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Affiliation(s)
- Ida Alm
- Biochemistry, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Sara García-Linares
- Departamento de Bioquímica y Biología Molecular I, Universidad Complutense, Madrid, Spain
| | - José G Gavilanes
- Departamento de Bioquímica y Biología Molecular I, Universidad Complutense, Madrid, Spain
| | | | - J Peter Slotte
- Biochemistry, Department of Biosciences, Åbo Akademi University, Turku, Finland.
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34
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Róg T, Vattulainen I. Cholesterol, sphingolipids, and glycolipids: what do we know about their role in raft-like membranes? Chem Phys Lipids 2014; 184:82-104. [PMID: 25444976 DOI: 10.1016/j.chemphyslip.2014.10.004] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Revised: 10/24/2014] [Accepted: 10/25/2014] [Indexed: 12/14/2022]
Abstract
Lipids rafts are considered to be functional nanoscale membrane domains enriched in cholesterol and sphingolipids, characteristic in particular of the external leaflet of cell membranes. Lipids, together with membrane-associated proteins, are therefore considered to form nanoscale units with potential specific functions. Although the understanding of the structure of rafts in living cells is quite limited, the possible functions of rafts are widely discussed in the literature, highlighting their importance in cellular functions. In this review, we discuss the understanding of rafts that has emerged based on recent atomistic and coarse-grained molecular dynamics simulation studies on the key lipid raft components, which include cholesterol, sphingolipids, glycolipids, and the proteins interacting with these classes of lipids. The simulation results are compared to experiments when possible.
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Affiliation(s)
- Tomasz Róg
- Department of Physics, Tampere University of Technology, Tampere, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, Tampere, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark.
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35
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Parkkila P, Stefl M, Olżyńska A, Hof M, Kinnunen PKJ. Phospholipid lateral diffusion in phosphatidylcholine-sphingomyelin-cholesterol monolayers; effects of oxidatively truncated phosphatidylcholines. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:167-73. [PMID: 25450344 DOI: 10.1016/j.bbamem.2014.10.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/10/2014] [Accepted: 10/20/2014] [Indexed: 11/15/2022]
Abstract
Oxidative stress is involved in a number of pathological conditions and the generated oxidatively modified lipids influence membrane properties and functions, including lipid-protein interactions and cellular signaling. Brewster angle microscopy demonstrated oxidatively truncated phosphatidylcholines to promote phase separation in monolayers of 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine (POPC), sphingomyelin (SM) and cholesterol (Chol). More specifically, 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC), was found to increase the miscibility transition pressure of the SM/Chol-phase. Lateral diffusion of lipids is influenced by a variety of membrane properties, thus making it a sensitive parameter to observe the coexistence of different lipid phases, for instance. The dependence on lipid lateral packing of the lateral diffusion of fluorophore-containing phospholipid analogs was investigated in Langmuir monolayers composed of POPC, SM, and Chol and additionally containing oxidatively truncated phosphatidylcholines, using fluorescence correlation spectroscopy (FCS). To our knowledge, these are the first FCS results on miscibility transition in ternary lipid monolayers, confirming previous results obtained using Brewster angle microscopy on such lipid monolayers. Wide-field fluorescence microscopy was additionally employed to verify the transition, i.e. the loss and reformation of SM/Chol domains.
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Affiliation(s)
- Petteri Parkkila
- Helsinki Biophysics & Biomembrane Group, Department of Biomedical Engineering and Computational Science, School of Science, Aalto University, Espoo, Finland
| | - Martin Stefl
- J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Agnieszka Olżyńska
- J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Paavo K J Kinnunen
- Helsinki Biophysics & Biomembrane Group, Department of Biomedical Engineering and Computational Science, School of Science, Aalto University, Espoo, Finland.
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36
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Yasuda T, Kinoshita M, Murata M, Matsumori N. Detailed comparison of deuterium quadrupole profiles between sphingomyelin and phosphatidylcholine bilayers. Biophys J 2014; 106:631-8. [PMID: 24507603 DOI: 10.1016/j.bpj.2013.12.034] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/25/2013] [Accepted: 12/26/2013] [Indexed: 11/25/2022] Open
Abstract
Lipid rafts are microdomains rich in sphingomyelin (SM) and cholesterol (Chol). The essential question is why natural lipid rafts prefer SM rather than saturated diacyl glycerophosphocholine, although both form ordered membranes with Chol in model systems. Hence in this study, we synthesized site-specifically deuterated 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholines that match the acyl chain length of stearoyl-SM (SSM), and compared their deuterium quadrupole coupling profiles in detail. The results suggest a deeper distribution of Chol in the SSM membranes, a lower entropic penalty upon accommodation of Chol in SSM membranes, and a higher thermal stability of acyl-chain orders in the SSM-Chol bilayers than in the 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholine-Chol system at various Chol concentrations. The entropy effect and thermal stability should render SM a more preferred raft constituent than saturated diacyl glycerophosphocholine. Our data also demonstrate that the selective and comprehensive deuteration strategy is indispensable for accurate comparison of order profiles.
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Affiliation(s)
- Tomokazu Yasuda
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Masanao Kinoshita
- Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Nobuaki Matsumori
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
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37
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Essentially all excess fibroblast cholesterol moves from plasma membranes to intracellular compartments. PLoS One 2014; 9:e98482. [PMID: 25014655 PMCID: PMC4094430 DOI: 10.1371/journal.pone.0098482] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 05/02/2014] [Indexed: 11/19/2022] Open
Abstract
It has been shown that modestly increasing plasma membrane cholesterol beyond its physiological set point greatly increases the endoplasmic reticulum and mitochondrial pools, thereby eliciting manifold feedback responses that return cell cholesterol to its resting state. The question arises whether this homeostatic mechanism reflects the targeting of cell surface cholesterol to specific intracellular sites or its general equilibration among the organelles. We now show that human fibroblast cholesterol can be increased as much as two-fold from 2-hydroxypropyl-β-cyclodextrin without changing the size of the cell surface pool. Rather, essentially all of the added cholesterol disperses rapidly among cytoplasmic membranes, increasing their overall cholesterol content by as much as five-fold. We conclude that the level of plasma membrane cholesterol is normally at capacity and that even small increments above this physiological set point redistribute essentially entirely to intracellular membranes, perhaps down their chemical activity gradients.
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38
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Pourmousa M, Róg T, Mikkeli R, Vattulainen L, Solanko LM, Wüstner D, List NH, Kongsted J, Karttunen M. Dehydroergosterol as an Analogue for Cholesterol: Why It Mimics Cholesterol So Well—or Does It? J Phys Chem B 2014; 118:7345-57. [DOI: 10.1021/jp406883k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Mohsen Pourmousa
- Department
of Physics, Tampere University of Technology, Korkeakoulunkatu 3, 33720 Tampere, Finland
| | - Tomasz Róg
- Department
of Physics, Tampere University of Technology, Korkeakoulunkatu 3, 33720 Tampere, Finland
| | - Risto Mikkeli
- Department
of Applied Physics, Aalto University, P.O. Box 11100, FI-00076 Aalto, Finland
| | - llpo Vattulainen
- Department
of Physics, Tampere University of Technology, Korkeakoulunkatu 3, 33720 Tampere, Finland
- MEMPHYS−Center
of Biomembrane Physics, Physics Department, University of Southern Denmark, Odense, Denmark
| | | | | | | | | | - Mikko Karttunen
- Department
of Chemistry and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo N2L 3G1, Ontario, Canada
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Nicolson GL. The Fluid—Mosaic Model of Membrane Structure: Still relevant to understanding the structure, function and dynamics of biological membranes after more than 40years. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:1451-66. [DOI: 10.1016/j.bbamem.2013.10.019] [Citation(s) in RCA: 442] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 10/08/2013] [Accepted: 10/18/2013] [Indexed: 12/21/2022]
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40
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Abstract
The Fluid-Mosaic Membrane Model of cell membrane structure was based on thermodynamic principals and the available data on component lateral mobility within the membrane plane [Singer SJ, Nicolson GL. The Fluid Mosaic Model of the structure of cell membranes. Science 1972; 175: 720-731]. After more than forty years the model remains relevant for describing the basic nano-scale structures of a variety of biological membranes. More recent information, however, has shown the importance of specialized membrane domains, such as lipid rafts and protein complexes, in describing the macrostructure and dynamics of biological membranes. In addition, membrane-associated cytoskeletal structures and extracellular matrix also play roles in limiting the mobility and range of motion of membrane components and add new layers of complexity and hierarchy to the original model. An updated Fluid-Mosaic Membrane Model is described, where more emphasis has been placed on the mosaic nature of cellular membranes where protein and lipid components are more crowded and limited in their movements in the membrane plane by lipid-lipid, protein-protein and lipid-protein interactions as well as cell-matrix, cell-cell and cytoskeletal interactions. These interactions are important in restraining membrane components and maintaining the unique mosaic organization of cell membranes into functional, dynamic domains.
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Affiliation(s)
- Garth L Nicolson
- The Institute for Molecular Medicine, Department of Molecular Pathology, Huntington Beach, CA, USA
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41
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Hsieh CJ, Chen YW, Hwang DW. Effects of cholesterol on membrane molecular dynamics studied by fast field cycling NMR relaxometry. Phys Chem Chem Phys 2013; 15:16634-40. [PMID: 23965762 DOI: 10.1039/c3cp51739j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Biological membranes are complex structures composed of various lipids and proteins. Different membrane compositions affect viscoelastic and hydrodynamic properties of membranes, which are critical to their functions. Lipid bilayer vesicles inserted by cholesterol not only enhance membrane surface motional behavior but also strengthen vesicle stability. Cholesterol-rich vesicles are similar to cell membranes in structure and composition. Therefore, cholesterol-rich vesicles can represent a typical model for studying membrane dynamics and functions. In this study, nuclear magnetic relaxation dispersion was used to investigate the detailed molecular dynamics of membrane differences between vesicles and cholesterol vesicles in the temperature range of 278-298 K. Vesicles of two different sizes were prepared. The effect of cholesterol mainly affected the order fluctuation of membranes and the diffusional motion of lipid molecules. In addition, phase variations were also observed in liposomes that contained cholesterol from analyses of the distances between lipid molecules.
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Affiliation(s)
- Chu-Jung Hsieh
- Department of Chemistry and Biochemistry, National Chung Cheng University, No. 168, Sec. 1, University Rd., Min-Hsiung Township Chiayi, 621, Taiwan.
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42
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Petruk AA, Varriale S, Coscia MR, Mazzarella L, Merlino A, Oreste U. The structure of the CD3 ζζ transmembrane dimer in POPC and raft-like lipid bilayer: a molecular dynamics study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2637-45. [PMID: 23896554 DOI: 10.1016/j.bbamem.2013.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 07/05/2013] [Accepted: 07/16/2013] [Indexed: 12/15/2022]
Abstract
Plasma membrane lipids significantly affect assembly and activity of many signaling networks. The present work is aimed at analyzing, by molecular dynamics simulations, the structure and dynamics of the CD3 ζζ dimer in palmitoyl-oleoyl-phosphatidylcholine bilayer (POPC) and in POPC/cholesterol/sphingomyelin bilayer, which resembles the raft membrane microdomain supposed to be the site of the signal transducing machinery. Both POPC and raft-like environment produce significant alterations in structure and flexibility of the CD3 ζζ with respect to nuclear magnetic resonance (NMR) model: the dimer is more compact, its secondary structure is slightly less ordered, the arrangement of the Asp6 pair, which is important for binding to the Arg residue in the alpha chain of the T cell receptor (TCR), is stabilized by water molecules. Different interactions of charged residues with lipids at the lipid-cytoplasm boundary occur when the two environments are compared. Furthermore, in contrast to what is observed in POPC, in the raft-like environment correlated motions between transmembrane and cytoplasmic regions are observed. Altogether the data suggest that when the TCR complex resides in the raft domains, the CD3 ζζ dimer assumes a specific conformation probably necessary to the correct signal transduction.
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Affiliation(s)
- Ariel Alcides Petruk
- Instituto Superior de Investigaciones Biológicas (INSIBIO-CONICET), Chacabuco 461, S. M. de Tucumán, Tucumán T4000ILI, Argentina
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43
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Rabinovich AL, Lyubartsev AP. Computer simulation of lipid membranes: Methodology and achievements. POLYMER SCIENCE SERIES C 2013. [DOI: 10.1134/s1811238213070060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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44
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Wriessnegger T, Pichler H. Yeast metabolic engineering – Targeting sterol metabolism and terpenoid formation. Prog Lipid Res 2013; 52:277-93. [DOI: 10.1016/j.plipres.2013.03.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Revised: 03/26/2013] [Accepted: 03/27/2013] [Indexed: 12/28/2022]
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45
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Kett PJN, Casford MTL, Davies PB. Orientation of cholesterol in hybrid bilayer membranes calculated from the phases of methyl resonances in sum frequency generation spectra. J Chem Phys 2013; 138:225101. [DOI: 10.1063/1.4807854] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- P J N Kett
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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Reis A, Rudnitskaya A, Blackburn GJ, Mohd Fauzi N, Pitt AR, Spickett CM. A comparison of five lipid extraction solvent systems for lipidomic studies of human LDL. J Lipid Res 2013; 54:1812-24. [PMID: 23670529 DOI: 10.1194/jlr.m034330] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipidome profile of fluids and tissues is a growing field as the role of lipids as signaling molecules is increasingly understood, relying on an effective and representative extraction of the lipids present. A number of solvent systems suitable for lipid extraction are commonly in use, though no comprehensive investigation of their effectiveness across multiple lipid classes has been carried out. To address this, human LDL from normolipidemic volunteers was used to evaluate five different solvent extraction protocols [Folch, Bligh and Dyer, acidified Bligh and Dyer, methanol (MeOH)-tert-butyl methyl ether (TBME), and hexane-isopropanol] and the extracted lipids were analyzed by LC-MS in a high-resolution instrument equipped with polarity switching. Overall, more than 350 different lipid species from 19 lipid subclasses were identified. Solvent composition had a small effect on the extraction of predominant lipid classes (triacylglycerides, cholesterol esters, and phosphatidylcholines). In contrast, extraction of less abundant lipids (phosphatidylinositols, lyso-lipids, ceramides, and cholesterol sulfates) was greatly influenced by the solvent system used. Overall, the Folch method was most effective for the extraction of a broad range of lipid classes in LDL, although the hexane-isopropanol method was best for apolar lipids and the MeOH-TBME method was suitable for lactosyl ceramides.
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Affiliation(s)
- Ana Reis
- School of Life and Health Sciences, Aston University, Birmingham, UK.
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Solid-state ¹³C NMR reveals annealing of raft-like membranes containing cholesterol by the intrinsically disordered protein α-Synuclein. J Mol Biol 2013; 425:2973-87. [PMID: 23583776 DOI: 10.1016/j.jmb.2013.04.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 03/14/2013] [Accepted: 04/02/2013] [Indexed: 11/20/2022]
Abstract
Misfolding and aggregation of the intrinsically disordered protein α-Synuclein (αS) in Lewy body plaques are characteristic markers of late-stage Parkinson's disease. It is well established that membrane binding is initiated at the N-terminus of the protein and affects biasing of conformational ensembles of αS. However, little is understood about the effect of αS on the membrane lipid bilayer. One hypothesis is that intrinsically disordered αS alters the structural properties of the membrane, thereby stabilizing the bilayer against fusion. Here, we used two-dimensional (13)C separated local-field NMR to study interaction of the wild-type α-Synuclein (wt-αS) or its N-terminal (1-25) amino acid sequence (N-αS) with a cholesterol-enriched ternary membrane system. This lipid bilayer mimics cellular raft-like domains in the brain that are proposed to be involved in neuronal membrane fusion. The two-dimensional dipolar-recoupling pulse sequence DROSS (dipolar recoupling on-axis with scaling and shape preservation) was implemented to measure isotropic (13)C chemical shifts and (13)C-(1)H residual dipolar couplings under magic-angle spinning. Site-specific changes in NMR chemical shifts and segmental order parameters indicate that both wt-αS and N-αS bind to the membrane interface and change lipid packing within raft-like membranes. Mean-torque modeling of (13)C-(1)H NMR order parameters shows that αS induces a remarkable thinning of the bilayer (≈6Å), accompanied by an increase in phospholipid cross-sectional area (≈10Å(2)). This perturbation is characterized as membrane annealing and entails structural remodeling of the raft-like liquid-ordered phase. We propose this process is implicated in regulation of synaptic membrane fusion that may be altered by aggregation of αS in Parkinson's disease.
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Petruzielo RS, Heberle FA, Drazba P, Katsaras J, Feigenson GW. Phase behavior and domain size in sphingomyelin-containing lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1828:1302-13. [PMID: 23337475 PMCID: PMC3582766 DOI: 10.1016/j.bbamem.2013.01.007] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 01/07/2013] [Accepted: 01/09/2013] [Indexed: 11/15/2022]
Abstract
Membrane raft size measurements are crucial to understanding the stability and functionality of rafts in cells. The challenge of accurately measuring raft size is evidenced by the disparate reports of domain sizes, which range from nanometers to microns for the ternary model membrane system sphingomyelin (SM)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/cholesterol (Chol). Using Förster resonance energy transfer (FRET) and differential scanning calorimetry (DSC), we established phase diagrams for porcine brain SM (bSM)/dioleoyl-sn-glycero-3-phosphocholine (DOPC)/Chol and bSM/POPC/Chol at 15 and 25°C. By combining two techniques with different spatial sensitivities, namely FRET and small-angle neutron scattering (SANS), we have significantly narrowed the uncertainty in domain size estimates for bSM/POPC/Chol mixtures. Compositional trends in FRET data revealed coexisting domains at 15 and 25°C for both mixtures, while SANS measurements detected no domain formation for bSM/POPC/Chol. Together these results indicate that liquid domains in bSM/POPC/Chol are between 2 and 7nm in radius at 25°C: that is, domains must be on the order of the 2-6nm Förster distance of the FRET probes, but smaller than the ~7nm minimum cluster size detectable with SANS. However, for palmitoyl SM (PSM)/POPC/Chol at a similar composition, SANS detected coexisting liquid domains. This increase in domain size upon replacing the natural SM component (which consists of a mixture of chain lengths) with synthetic PSM, suggests a role for SM chain length in modulating raft size in vivo.
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Affiliation(s)
| | - Frederick A. Heberle
- Biology and Soft Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6100, USA
| | - Paul Drazba
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996-1200, USA
| | - John Katsaras
- Biology and Soft Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6100, USA
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996-1200, USA
- Canadian Neutron Beam Centre, National Research Council, Chalk River, Ontario, Canada K0J 1J0
- Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6453, USA
| | - Gerald W. Feigenson
- Department of Molecular Biology and Genetics, Field of Biophysics, Cornell University, Ithaca, NY, 14853 USA
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Peter Slotte J. Molecular properties of various structurally defined sphingomyelins -- correlation of structure with function. Prog Lipid Res 2013; 52:206-19. [PMID: 23295259 DOI: 10.1016/j.plipres.2012.12.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 12/20/2012] [Accepted: 12/21/2012] [Indexed: 01/10/2023]
Abstract
Sphingomyelins are important phospholipids in plasma membranes of most cells. Because of their dominantly saturated nature, they affect the lateral structure of membranes, and contribute to the regulation of cholesterol distribution within membranes, and in cells. However, the abundance of molecular species present in cells also implies that sphingomyelins have other, more specific functions. Many of these functions are currently unknown, but are under extensive study. Mostly model membrane studies have shown that sphingomyelins (and other sphingolipids), in contrast to glycerophospholipids, have important hydrogen bonding properties which in several important ways confer specific functional properties to this abundant class of membrane phospholipids. The often very asymmetric nature of sphingomyelins, arising from mismatch in length between the long chain base and N-acyl chains, also impose specific properties (e.g., interdigitation) to sphingomyelins not seen with glycerophospholipids. In this review, the latest sphingomyelin literature will be scrutinized, and an effort will be made to correlate the molecular structure of sphingomyelin with functional properties. In particular, the effects of head group properties, interfacial hydrogen bonding, long chain base hydroxylation, N-acyl chain hydroxylation, and N-acyl chain methyl-branching will be discussed.
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Affiliation(s)
- J Peter Slotte
- Biochemistry, Department of Biosciences, Åbo Akademi University, Tykistökatu 6A, 20520 Turku, Finland.
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50
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Polley A, Vemparala S. Partitioning of ethanol in multi-component membranes: Effects on membrane structure. Chem Phys Lipids 2013; 166:1-11. [DOI: 10.1016/j.chemphyslip.2012.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 11/23/2012] [Accepted: 11/24/2012] [Indexed: 12/12/2022]
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