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Shih KC, Leriche G, Liu CH, He J, John VT, Fang J, Barker JG, Nagao M, Yang L, Yang J, Nieh MP. Antivesiculation and Complete Unbinding of Tail-Tethered Lipids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1688-1697. [PMID: 38186288 DOI: 10.1021/acs.langmuir.3c02663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
We report the effect of tail-tethering on vesiculation and complete unbinding of bilayered membranes. Amphiphilic molecules of a bolalipid, resembling the tail-tethered molecular structure of archaeal lipids, with two identical zwitterionic phosphatidylcholine headgroups self-assemble into a large flat lamellar membrane, in contrast to the multilamellar vesicles (MLVs) observed in its counterpart, monopolar nontethered zwitterionic lipids. The antivesiculation is confirmed by small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (cyro-TEM). With the net charge of zero and higher bending rigidity of the membrane (confirmed by neutron spin echo (NSE) spectroscopy), the current membrane theory would predict that membranes should stack with each other (aka "bind") due to dominant van der Waals attraction, while the outcome of the nonstacking ("unbinding") membrane suggests that the theory needs to include entropic contribution for the nonvesicular structures. This report pioneers an understanding of how the tail-tethering of amphiphiles affects the structure, enabling better control over the final nanoscale morphology.
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Affiliation(s)
| | - Geoffray Leriche
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | | | - Jibao He
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Vijay T John
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | | | - John G Barker
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Michihiro Nagao
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United States
| | - Lin Yang
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Jerry Yang
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
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2
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Pinigin KV, Akimov SA. The Membrane-Mediated Interaction of Liquid-Ordered Lipid Domains in the Presence of Amphipathic Peptides. MEMBRANES 2023; 13:816. [PMID: 37887988 PMCID: PMC10608175 DOI: 10.3390/membranes13100816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/08/2023] [Accepted: 09/22/2023] [Indexed: 10/28/2023]
Abstract
The lipid membranes of living cells are composed of a large number of lipid types and can undergo phase separation with the formation of nanometer-scale liquid-ordered lipid domains, also called rafts. Raft coalescence, i.e., the fusion of lipid domains, is involved in important cell processes, such as signaling and trafficking. In this work, within the framework of the theory of elasticity of lipid membranes, we explore how amphipathic peptides adsorbed on lipid membranes may affect the domain-domain fusion processes. We show that the elastic deformations of lipid membranes drive amphipathic peptides to the boundary of lipid domains, which leads to an increase in the average energy barrier of the domain-domain fusion, even if the surface concentration of amphipathic peptides is low and the domain boundaries are only partially occupied by the peptides. This inhibition of the fusion of lipid domains may lead to negative side effects of using amphipathic peptides as antimicrobial agents.
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Affiliation(s)
- Konstantin V. Pinigin
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia
| | - Sergey A. Akimov
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia
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3
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Li S, Huang F, Xia T, Shi Y, Yue T. Phosphatidylinositol 4,5-Bisphosphate Sensing Lipid Raft via Inter-Leaflet Coupling Regulated by Acyl Chain Length of Sphingomyelin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:5995-6005. [PMID: 37086192 DOI: 10.1021/acs.langmuir.2c03492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PIP2) is an important molecule located at the inner leaflet of cell membrane, where it serves as anchoring sites for a cohort of membrane-associated molecules and as a broad-reaching signaling intermediate. The lipid raft is thought as the major platform recruiting proteins for signal transduction and also known to mediate PIP2 accumulation across the membrane. While the significance of this cross-membrane coupling is increasingly appreciated, it remains unclear whether and how PIP2 senses the dynamic change of the ordered lipid domains over the packed hydrophobic core of the bilayer. Herein, by means of molecular dynamic simulation, we reveal that inner PIP2 molecules can sense the outer lipid domain via inter-leaflet coupling, and the coupling manner is dictated by the acyl chain length of sphingomyelin (SM) partitioned to the lipid domain. Shorter SM promotes membrane domain registration, whereby PIP2 accumulates beneath the domain across the membrane. In contrast, the anti-registration is thermodynamically preferred if the lipid domain has longer SM due to the hydrophobic mismatch between the corresponding acyl chains in SM and PIP2. In this case, PIP2 is expelled by the domain with a higher diffusivity. These results provide molecular insights into the regulatory mechanism of correlation between the outer lipid domain and inner PIP2, both of which are critical components for cell signal transduction.
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Affiliation(s)
- Shixin Li
- College of Bioscience and Biotechnology and Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Fang Huang
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Tie Xia
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yan Shi
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- Department of Microbiology, Immunology & Infectious Disease and Snyder Institute, University of Calgary, Calgary, Alberta 00000, Canada
| | - Tongtao Yue
- Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, Shandong 266100, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China
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4
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Kalutskii MA, Galimzyanov TR, Pinigin KV. Determination of elastic parameters of lipid membranes from simulation under varied external pressure. Phys Rev E 2023; 107:024414. [PMID: 36932616 DOI: 10.1103/physreve.107.024414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Many cellular processes such as endocytosis, exocytosis, and vesicle trafficking involve membrane deformations, which can be analyzed in the framework of the elastic theories of lipid membranes. These models operate with phenomenological elastic parameters. A connection between these parameters and the internal structure of lipid membranes can be provided by three-dimensional (3D) elastic theories. Considering a membrane as a 3D layer, Campelo et al. [F. Campelo et al., Adv. Colloid Interface Sci. 208, 25 (2014)10.1016/j.cis.2014.01.018] developed a theoretical basis for the calculation of elastic parameters. In this work we generalize and improve this approach by considering a more general condition of global incompressibility instead of local incompressibility. Crucially, we find an important correction to the theory of Campelo et al., which if not taken into account leads to a significant miscalculation of elastic parameters. With the total volume conservation taken into account, we derive an expression for the local Poisson's ratio, which determines how the local volume changes upon stretching and permits a more precise determination of elastic parameters. Also, we substantially simplify the procedure by calculating the derivatives of the moments of the local tension with respect to stretching instead of calculating the local stretching modulus. We obtain a relation between the Gaussian curvature modulus as a function of stretching and the bending modulus, showing that these two elastic parameters are not independent, as was previously assumed. The proposed algorithm is applied to membranes composed of pure dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), and their mixture. The following elastic parameters of these systems are obtained: the monolayer bending and stretching moduli, spontaneous curvature, neutral surface position, and local Poisson's ratio. It is shown that the bending modulus of the DPPC/DOPC mixture follows a more complex trend than predicted by the classical Reuss averaging, which is often employed in theoretical frameworks.
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Affiliation(s)
- Maksim A Kalutskii
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS," 4 Leninskiy Prospekt, 119049 Moscow, Russia
| | - Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS," 4 Leninskiy Prospekt, 119049 Moscow, Russia
| | - Konstantin V Pinigin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia
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5
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Kondrashov OV, Akimov SA. A Mechanism of Double-Membrane Vesicle Formation from Liquid-Ordered/Liquid-Disordered Phase Separated Spherical Membrane. MEMBRANES 2022; 13:25. [PMID: 36676832 PMCID: PMC9862188 DOI: 10.3390/membranes13010025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/12/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
Genome replication of coronaviruses takes place in specific cellular compartments, in so-called double-membrane vesicles (DMVs), formed from the endoplasmic reticulum (ER). An intensive production of DMVs is induced by non-structural viral proteins. Here, we proposed a possible mechanism of the DMV formation from ER-derived spherical vesicles where liquid-ordered and liquid-disordered lipid phases coexist. These vesicles are supposed to divide into two homogeneous liquid-ordered and liquid-disordered vesicles. The formation of two spherical vesicles constituting DMV requires a mechanical work to be performed. We considered the excess energy of the boundary between the coexisting lipid phases as the main driving force behind the division of the initial vesicle. Explicitly accounting for the energy of elastic deformations and the interphase boundary energy, we analyzed a range of physical parameters where the DMV formation is possible. We concluded that this process can principally take place in a very narrow range of system parameters. The most probable diameter of DMVs formed according to the proposed mechanism appeared to be approximately 220 nm, in an agreement with the average diameter of DMVs observed in vivo. Our consideration predicts the DMV size to be strongly limited from above. The developed analysis can be utilized for the production of DMVs in model systems.
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Krasnobaev VD, Batishchev OV. The Role of Lipid Domains and Physical Properties of Membranes in the Development of Age-Related Neurodegenerative Diseases. BIOCHEMISTRY (MOSCOW), SUPPLEMENT SERIES A: MEMBRANE AND CELL BIOLOGY 2022. [DOI: 10.1134/s199074782209001x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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7
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Molotkovsky RJ, Kuzmin PI. Fusion of Peroxisome and Lipid Droplet Membranes: Expansion of a π-Shaped Structure. BIOCHEMISTRY (MOSCOW), SUPPLEMENT SERIES A: MEMBRANE AND CELL BIOLOGY 2022. [DOI: 10.1134/s1990747822050105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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8
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Pinigin KV. Determination of Elastic Parameters of Lipid Membranes with Molecular Dynamics: A Review of Approaches and Theoretical Aspects. MEMBRANES 2022; 12:membranes12111149. [PMID: 36422141 PMCID: PMC9692374 DOI: 10.3390/membranes12111149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/07/2022] [Accepted: 11/10/2022] [Indexed: 05/12/2023]
Abstract
Lipid membranes are abundant in living organisms, where they constitute a surrounding shell for cells and their organelles. There are many circumstances in which the deformations of lipid membranes are involved in living cells: fusion and fission, membrane-mediated interaction between membrane inclusions, lipid-protein interaction, formation of pores, etc. In all of these cases, elastic parameters of lipid membranes are important for the description of membrane deformations, as these parameters determine energy barriers and characteristic times of membrane-involved phenomena. Since the development of molecular dynamics (MD), a variety of in silico methods have been proposed for the determination of elastic parameters of simulated lipid membranes. These MD methods allow for the consideration of details unattainable in experimental techniques and represent a distinct scientific field, which is rapidly developing. This work provides a review of these MD approaches with a focus on theoretical aspects. Two main challenges are identified: (i) the ambiguity in the transition from the continuum description of elastic theories to the discrete representation of MD simulations, and (ii) the determination of intrinsic elastic parameters of lipid mixtures, which is complicated due to the composition-curvature coupling effect.
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Affiliation(s)
- Konstantin V Pinigin
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia
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9
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Kalutsky MA, Galimzyanov TR, Molotkovsky RJ. A Model of Lipid Monolayer-Bilayer Fusion of Lipid Droplets and Peroxisomes. MEMBRANES 2022; 12:membranes12100992. [PMID: 36295751 PMCID: PMC9612070 DOI: 10.3390/membranes12100992] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/06/2022] [Accepted: 10/10/2022] [Indexed: 06/01/2023]
Abstract
Lipid droplets are unique organelles that store neutral lipids encapsulated by the lipid monolayer. In some processes of cellular metabolism, lipid droplets interact with peroxisomes resulting in the fusion of their envelopes and the formation of protrusions of the peroxisome monolayer, called pexopodia. The formation of pexopodia is facilitated by free fatty acids generated during lipolysis within lipid droplets. In this work, we studied the fusion of monolayer and bilayer membranes during the interaction between lipid droplets and peroxisomes. To this end, we built the energy trajectory of this process using the continuum elasticity theory and investigated the molecular details of the fusion structures utilizing molecular dynamics. We divided the fusion process into two stages: formation of a stalk and its consequent expansion into pexopodia. We found that in the considered system, the stalk was energetically more stable and had a lower energy barrier of formation compared to the case of bilayer fusion. The further evolution of the stalk depended on the value of the spontaneous curvature of the membrane in a threshold manner. We attributed the possible expansion of the stalk to the incorporation of free fatty acids into the stalk region. The developed model allowed describing quantitatively the process of monolayer-bilayer fusion.
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Affiliation(s)
- Maksim A. Kalutsky
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology “MISiS”, 4 Leninskiy Prospekt, 119049 Moscow, Russia
| | - Timur R. Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia
| | - Rodion J. Molotkovsky
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia
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10
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Krasnobaev VD, Galimzyanov TR, Akimov SA, Batishchev OV. Lysolipids regulate raft size distribution. Front Mol Biosci 2022; 9:1021321. [PMID: 36275621 PMCID: PMC9581197 DOI: 10.3389/fmolb.2022.1021321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The lipid matrix of cellular membranes, directly and indirectly, regulates many vital functions of the cell. The diversity of lipids in membranes leads to the formation of ordered domains called rafts, which play a crucial role in signal transduction, protein sorting and other cellular processes. Rafts are believed to impact the development of different neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, Huntington’s ones, amyotrophic lateral sclerosis, some types of cancer, etc. These diseases correlate with the change in the membrane lipid composition resulting from an oxidative stress, age-related processes, dysfunction of proteins, and many others. In particular, a lot of studies report a significant rise in the level of lysolipids. Physicochemical properties of rafts are determined by membrane composition, in particular, by the content of lysolipids. Lysolipids may thus regulate raft-involving processes. However, the exact mechanism of such regulation is unknown. Although studying rafts in vivo still seems to be rather complicated, liquid-ordered domains are well observed in model systems. In the present study, we used atomic force microscopy (AFM) to examine how lysophospholipids influence the liquid-ordered domains in model ternary membranes. We demonstrated that even a small amount of lysolipids in a membrane significantly impacts domain size depending on the saturation of the lysolipid hydrocarbon tails and the amount of cholesterol. The mixture with the bigger relative fraction of cholesterol was more susceptible to the action of lysolipids. This data helped us to generalize our previous theoretical model of the domain size regulation by lipids with particular molecular shape expanding it to the case of lysolipids and dioleoylglycerol.
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Affiliation(s)
- Vladimir D. Krasnobaev
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
- Moscow Institute of Physics and Technology (National Research University), Dolgoprudny, Russia
| | - Timur R. Galimzyanov
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Sergey A. Akimov
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Oleg V. Batishchev
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
- *Correspondence: Oleg V. Batishchev,
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11
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Foley SL, Hossein A, Deserno M. Fluid-gel coexistence in lipid membranes under differential stress. Biophys J 2022; 121:2997-3009. [PMID: 35859420 PMCID: PMC9463654 DOI: 10.1016/j.bpj.2022.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/03/2022] [Accepted: 07/12/2022] [Indexed: 11/21/2022] Open
Abstract
A widely conserved property of many biological lipid bilayers is their asymmetry. In addition to having distinct compositions on its two sides, a membrane can also exhibit different tensions in its two leaflets, a state known as differential stress. Here, we examine how this stress can influence the phase behavior of the constituent lipid monolayers of a single-component membrane. For temperatures sufficiently close to, but still above, the main transition, molecular dynamics simulations show the emergence of finite gel domains within the compressed leaflet. We describe the thermodynamics of this phenomenon by adding two empirical single-leaflet free energies for the fluid-gel transition, each evaluated at its respective asymmetry-dependent lipid density. Finite size effects arising in simulation are included in the theory through a geometry-dependent interfacial term. Our model reproduces the phase coexistence observed in simulation. It could therefore be used to connect the "hidden variable" of differential stress to experimentally observable properties of the main phase transition. These ideas could be generalized to any first-order bilayer phase transition in the presence of asymmetry, including liquid-ordered/liquid-disordered phase separation.
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Affiliation(s)
- Samuel L Foley
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Amirali Hossein
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania; Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania.
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12
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Sharma A, Seal A, Iyer SS, Srivastava A. Enthalpic and entropic contributions to interleaflet coupling drive domain registration and antiregistration in biological membrane. Phys Rev E 2022; 105:044408. [PMID: 35590589 DOI: 10.1103/physreve.105.044408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 03/14/2022] [Indexed: 06/15/2023]
Abstract
Biological membrane is a complex self-assembly of lipids, sterols, and proteins organized as a fluid bilayer of two closely stacked lipid leaflets. Differential molecular interactions among its diverse constituents give rise to heterogeneities in the membrane lateral organization. Under certain conditions, heterogeneities in the two leaflets can be spatially synchronized and exist as registered domains across the bilayer. Several contrasting theories behind mechanisms that induce registration of nanoscale domains have been suggested. Following a recent study showing the effect of position of lipid tail unsaturation on domain registration behavior, we decided to develop an analytical theory to elucidate the driving forces that create and maintain domain registry across leaflets. Towards this, we formulated a Hamiltonian for a stacked lattice system where site variables capture the lipid molecular properties such as the position of unsaturation and various other interactions that could drive phase separation and interleaflet coupling. We solve the Hamiltonian using Monte Carlo simulations and create a complete phase diagram that reports the presence or absence of registered domains as a function of various Hamiltonian parameters. We find that the interleaflet coupling should be described as a competing enthalpic contribution due to interaction of lipid tail termini, primarily due to saturated-saturated interactions, and an interleaflet entropic contribution from overlap of unsaturated tail termini. A higher position of unsaturation is seen to provide weaker interleaflet coupling. Thermodynamically stable nanodomains could also be observed for certain points in the parameter space in our bilayer model, which were further verified by carrying out extended Monte Carlo simulations. These persistent noncoalescing registered nanodomains close to the lower end of the accepted nanodomain size range also point towards a possible "nanoscale" emulsion description of lateral heterogeneities in biological membrane leaflets.
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Affiliation(s)
- Akshara Sharma
- Department of Physics, Indian Institute of Science-Bangalore, C. V. Raman Road, Bangalore, Karnataka 560012, India
| | - Aniruddha Seal
- School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar, Khurda, Odisha 752050, India
| | - Sahithya S Iyer
- Molecular Biophysics Unit, Indian Institute of Science-Bangalore, C. V. Raman Road, Bangalore, Karnataka 560012, India
| | - Anand Srivastava
- Molecular Biophysics Unit, Indian Institute of Science-Bangalore, C. V. Raman Road, Bangalore, Karnataka 560012, India
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13
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Saitov A, Kalutsky MA, Galimzyanov TR, Glasnov T, Horner A, Akimov SA, Pohl P. Determinants of Lipid Domain Size. Int J Mol Sci 2022; 23:ijms23073502. [PMID: 35408861 PMCID: PMC8998648 DOI: 10.3390/ijms23073502] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/21/2022] [Accepted: 03/21/2022] [Indexed: 12/20/2022] Open
Abstract
Lipid domains less than 200 nm in size may form a scaffold, enabling the concerted function of plasma membrane proteins. The size-regulating mechanism is under debate. We tested the hypotheses that large values of spontaneous monolayer curvature are incompatible with micrometer-sized domains. Here, we used the transition of photoswitchable lipids from their cylindrical conformation to a conical conformation to increase the negative curvature of a bilayer-forming lipid mixture. In contrast to the hypothesis, pre-existing micrometer-sized domains did not dissipate in our planar bilayers, as indicated by fluorescence images and domain mobility measurements. Elasticity theory supports the observation by predicting the zero free energy gain for splitting large domains into smaller ones. It also indicates an alternative size-determining mechanism: The cone-shaped photolipids reduce the line tension associated with lipid deformations at the phase boundary and thus slow down the kinetics of domain fusion. The competing influence of two approaching domains on the deformation of the intervening lipids is responsible for the kinetic fusion trap. Our experiments indicate that the resulting local energy barrier may restrict the domain size in a dynamic system.
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Affiliation(s)
- Ali Saitov
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria; (A.S.); (A.H.)
| | - Maksim A. Kalutsky
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia; (M.A.K.); (T.R.G.); (S.A.A.)
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology “MISiS”, 4 Leninskiy Prospekt, 119049 Moscow, Russia
| | - Timur R. Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia; (M.A.K.); (T.R.G.); (S.A.A.)
| | - Toma Glasnov
- Institute of Chemistry, University of Graz, 8010 Graz, Austria;
| | - Andreas Horner
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria; (A.S.); (A.H.)
| | - Sergey A. Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy Prospekt, 119071 Moscow, Russia; (M.A.K.); (T.R.G.); (S.A.A.)
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria; (A.S.); (A.H.)
- Correspondence:
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14
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Pohl P. Biophysical Reviews' "Meet the Councilor Series"-a profile of Peter Pohl. Biophys Rev 2021; 13:839-844. [PMID: 35035592 PMCID: PMC8724173 DOI: 10.1007/s12551-021-00897-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 11/01/2021] [Indexed: 10/30/2022] Open
Abstract
It is my pleasure to write a few words to introduce myself to the readers of Biophysical Reviews as part of the "Meet the Councilor Series." Currently, I am serving the second period as IUPAB councilor after having been elected first in 2017. Initially, I studied Biophysics in Moscow (Russia) and later Medicine in Halle (Germany). My scientific carrier took me from the Medical School of the Martin Luther University of Halle-Wittenberg, via the Leibniz Institute for Molecular Pharmacology (Berlin) and the Institute for Biology at the Humboldt University (Berlin) to the Physics Department of the Johannes Kepler University in Linz (Austria). My key research interests lie in the molecular mechanisms of transport phenomena occurring at the lipid membrane, including (i) spontaneous and facilitated transport of water and other small molecules across membranes in reconstituted systems, (ii) proton migration along the membrane surface, (iii) protein translocation, and (iv) bilayer mechanics. Training of undergraduate, graduate, and postdoctoral researchers from diverse academic disciplines has been-and shall remain-a consistent part of my work.
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Affiliation(s)
- Peter Pohl
- Institute of Biophysics, Johannes Kepler University, Linz, Austria
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15
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Kondrashov OV, Pinigin KV, Akimov SA. Characteristic lengths of transmembrane peptides controlling their tilt and lateral distribution between membrane domains. Phys Rev E 2021; 104:044411. [PMID: 34781459 DOI: 10.1103/physreve.104.044411] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 10/04/2021] [Indexed: 11/07/2022]
Abstract
Lipids and proteins of plasma membranes of eukaryotic cells are supposed to form protein-lipid domains, characterized by a different molecular order, bilayer thickness, and elastic parameters. Several mechanisms of preferable distribution of transmembrane proteins to the ordered or disordered membrane domains have been revealed. The mismatch between the length of the protein transmembrane domain and hydrophobic thickness of the lipid bilayer is considered to be an important driving force of protein lateral sorting. Utilizing the continuum theory of elasticity, we analyzed optimal configurations and preferable membrane domains for single-pass transmembrane peptides of various hydrophobic lengths and effective molecular shapes. We obtained that short transmembrane peptides stand perpendicularly to the membrane plane. The exceedance of a certain characteristic length leads to the tilt of the peptide. This length depends on the bilayer thickness. Thus, in the membrane with coexisting ordered (thicker) and disordered (thinner) phases tilting of the peptide in each phase is governed by its individual characteristic length. The lateral distribution of the peptides between ordered and disordered membrane domains is shown to be described by two additional characteristic lengths. The exceedance of the smaller one drives the peptide towards a more ordered and thicker membrane, while the exceedance of the larger characteristic length switches the preferable membrane domain from ordered and thicker to disordered and thinner. Thus, membrane proteins with long enough transmembrane domains are predicted to accumulate in the thinner disordered membrane as compared to the thicker ordered bilayer. For hourglass-like and barrel-like shaped transmembrane peptides the specific regime of sorting was obtained: the peptides distributed almost equally between the phases in a wide range of peptide lengths. This finding allowed explaining the experimental data on lateral distribution of transmembrane peptide tLAT.
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Affiliation(s)
- Oleg V Kondrashov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Konstantin V Pinigin
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Sergey A Akimov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
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16
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Pinigin KV, Galimzyanov TR, Akimov SA. Amphipathic Peptides Impede Lipid Domain Fusion in Phase-Separated Membranes. MEMBRANES 2021; 11:membranes11110797. [PMID: 34832026 PMCID: PMC8618981 DOI: 10.3390/membranes11110797] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 11/16/2022]
Abstract
Cell membranes are heterogeneous in lipid composition which leads to the phase separation with the formation of nanoscopic liquid-ordered domains, also called rafts. There are multiple cell processes whereby the clustering of these domains into a larger one might be involved, which is responsible for such important processes as signal transduction, polarized sorting, or immune response. Currently, antimicrobial amphipathic peptides are considered promising antimicrobial, antiviral, and anticancer therapeutic agents. Here, within the framework of the classical theory of elasticity adapted for lipid membranes, we investigate how the presence of the peptides in a phase-separated membrane influences the fusion of the domains. We show that the peptides tend to occupy the boundaries of liquid-ordered domains and significantly increase the energy barrier of the domain-domain fusion, which might lead to misregulation of raft clustering and adverse consequences for normal cell processes.
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17
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Pinigin KV, Kuzmin PI, Akimov SA, Galimzyanov TR. Additional contributions to elastic energy of lipid membranes: Tilt-curvature coupling and curvature gradient. Phys Rev E 2020; 102:042406. [PMID: 33212684 DOI: 10.1103/physreve.102.042406] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 09/09/2020] [Indexed: 11/07/2022]
Abstract
Lipid bilayer membranes under biologically relevant conditions are flexible thin laterally fluid films consisting of two unimolecular layers (monolayers) each about 2 nm thick. On spatial scales much larger than the bilayer thickness, the membrane elasticity is well determined by its shape. The classical Helfrich theory considers the membrane as an elastic two-dimensional (2D) film, which has no particular internal structure. However, various local membrane heterogeneities can result in a lipids tilt relative to the membrane surface normal. On the basis of the classical elasticity theory of 3D bodies, Hamm and Kozlov [Eur. Phys. J. E 3, 323 (2000)10.1007/s101890070003] derived the most general energy functional, taking into account the tilt and lipid monolayer curvature. Recently, Terzi and Deserno [J. Chem. Phys. 147, 084702 (2017)10.1063/1.4990404] showed that Hamm and Kozlov's derivation was incomplete because the tilt-curvature coupling term had been missed. However, the energy functional derived by Terzi and Deserno appeared to be unstable, thereby being invalid for applications that require minimizations of the overall energy of deformations. Here, we derive a stable elastic energy functional, showing that the squared gradient of the curvature was missed in both of these works. This change in the energy functional arises from a more accurate consideration of the transverse shear deformation terms and their influence on the membrane stability. We also consider the influence of the prestress terms on the stability of the energy functional, and we show that it should be considered small and the effective Gaussian curvature should be neglected because of the stability requirements. We further generalize the theory, including the stretching-compressing deformation modes, and we provide the geometrical interpretation of the terms that were previously missed by Hamm and Kozlov. The physical consequences of the new terms are analyzed in the case of a membrane-mediated interaction of two amphipathic peptides located in the same monolayer. We also provide the expression for director fluctuations, comparing it with that obtained by Terzi and Deserno.
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Affiliation(s)
- Konstantin V Pinigin
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Peter I Kuzmin
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Sergey A Akimov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Timur R Galimzyanov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
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18
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Sarmento MJ, Ricardo JC, Amaro M, Šachl R. Organization of gangliosides into membrane nanodomains. FEBS Lett 2020; 594:3668-3697. [DOI: 10.1002/1873-3468.13871] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 01/04/2023]
Affiliation(s)
- Maria J. Sarmento
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences Prague 8 Czech Republic
| | - Joana C. Ricardo
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences Prague 8 Czech Republic
| | - Mariana Amaro
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences Prague 8 Czech Republic
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences Prague 8 Czech Republic
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19
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Sarmento MJ, Hof M, Šachl R. Interleaflet Coupling of Lipid Nanodomains - Insights From in vitro Systems. Front Cell Dev Biol 2020; 8:284. [PMID: 32411705 PMCID: PMC7198703 DOI: 10.3389/fcell.2020.00284] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/02/2020] [Indexed: 01/09/2023] Open
Abstract
The plasma membrane is a complex system, consisting of two layers of lipids and proteins compartmentalized into small structures called nanodomains. Despite the asymmetric composition of both leaflets, coupling between the layers is surprisingly strong. This can be evidenced, for example, by recent experimental studies performed on phospholipid giant unilamellar vesicles showing that nanodomains formed in the outer layer are perfectly registered with those in the inner leaflet. Similarly, microscopic phase separation in one leaflet can induce phase separation in the opposing leaflet that would otherwise be homogeneous. In this review, we summarize the current theoretical and experimental knowledge that led to the current view that domains are – irrespective of their size – commonly registered across the bilayer. Mechanisms inducing registration of nanodomains suggested by theory and calculations are discussed. Furthermore, domain coupling is evidenced by experimental studies based on the sparse number of methods that can resolve registered from independent nanodomains. Finally, implications that those findings using model membrane studies might have for cellular membranes are discussed.
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Affiliation(s)
- Maria J Sarmento
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
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20
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Saitov A, Akimov SA, Galimzyanov TR, Glasnov T, Pohl P. Ordered Lipid Domains Assemble via Concerted Recruitment of Constituents from Both Membrane Leaflets. PHYSICAL REVIEW LETTERS 2020; 124:108102. [PMID: 32216409 PMCID: PMC7115998 DOI: 10.1103/physrevlett.124.108102] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 02/26/2020] [Indexed: 06/10/2023]
Abstract
Lipid rafts serve as anchoring platforms for membrane proteins. Thus far they escaped direct observation by light microscopy due to their small size. Here we used differently colored dyes as reporters for the registration of both ordered and disordered lipids from the two leaves of a freestanding bilayer. Photoswitchable lipids dissolved or reformed the domains. Measurements of domain mobility indicated the presence of 120 nm wide ordered and 40 nm wide disordered domains. These sizes are in line with the predicted roles of line tension and membrane undulation as driving forces for alignment.
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Affiliation(s)
- Ali Saitov
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, Linz 4020, Austria
| | - Sergey A Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy prospekt, Moscow 119071, Russia
| | - Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy prospekt, Moscow 119071, Russia
| | - Toma Glasnov
- Institute of Chemistry, University of Graz, Heinrichstr. 28, 8010 Graz, Austria
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, Linz 4020, Austria
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21
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Pinigin KV, Kondrashov OV, Jiménez-Munguía I, Alexandrova VV, Batishchev OV, Galimzyanov TR, Akimov SA. Elastic deformations mediate interaction of the raft boundary with membrane inclusions leading to their effective lateral sorting. Sci Rep 2020; 10:4087. [PMID: 32139760 PMCID: PMC7058020 DOI: 10.1038/s41598-020-61110-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 02/18/2020] [Indexed: 02/06/2023] Open
Abstract
Liquid-ordered lipid domains represent a lateral inhomogeneity in cellular membranes. These domains have elastic and physicochemical properties different from those of the surrounding membrane. In particular, their thickness exceeds that of the disordered membrane. Thus, elastic deformations arise at the domain boundary in order to compensate for the thickness mismatch. In equilibrium, the deformations lead to an incomplete register of monolayer ordered domains: the elastic energy is minimal if domains in opposing monolayers lie on the top of each other, and their boundaries are laterally shifted by about 3 nm. This configuration introduces a region, composed of one ordered and one disordered monolayers, with an intermediate bilayer thickness. Besides, a jump in a local monolayer curvature takes place in this intermediate region, concentrating here most of the elastic stress. This region can participate in a lateral sorting of membrane inclusions by offering them an optimal bilayer thickness and local curvature conditions. In the present study, we consider the sorting of deformable lipid inclusions, undeformable peripheral and deeply incorporated peptide inclusions, and undeformable transmembrane inclusions of different molecular geometry. With rare exceptions, all types of inclusions have an affinity to the ordered domain boundary as compared to the bulk phases. The optimal lateral distribution of inclusions allows relaxing the elastic stress at the boundary of domains.
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Affiliation(s)
- Konstantin V Pinigin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia
| | - Oleg V Kondrashov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia
| | - Irene Jiménez-Munguía
- National University of Science and Technology "MISiS", 4 Leninskiy prospect, Moscow, 119049, Russia
| | | | - Oleg V Batishchev
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia
| | - Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia
| | - Sergey A Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia.
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22
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Ermakov YA, Sokolov VS, Akimov SA, Batishchev OV. Physicochemical and Electrochemical Aspects of the Functioning of Biological Membranes. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2020. [DOI: 10.1134/s0036024420030085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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The Effect of Transmembrane Protein Shape on Surrounding Lipid Domain Formation by Wetting. Biomolecules 2019; 9:biom9110729. [PMID: 31726783 PMCID: PMC6920788 DOI: 10.3390/biom9110729] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 11/09/2019] [Accepted: 11/11/2019] [Indexed: 12/11/2022] Open
Abstract
Signal transduction through cellular membranes requires the highly specific and coordinated work of specialized proteins. Proper functioning of these proteins is provided by an interplay between them and the lipid environment. Liquid-ordered lipid domains are believed to be important players here, however, it is still unclear whether conditions for a phase separation required for lipid domain formation exist in cellular membranes. Moreover, membrane leaflets are compositionally asymmetric, that could be an obstacle for the formation of symmetric domains spanning the lipid bilayer. We theoretically show that the presence of protein in the membrane leads to the formation of a stable liquid-ordered lipid phase around it by the mechanism of protein wetting by lipids, even in the absence of conditions necessary for the global phase separation in the membrane. Moreover, we show that protein shape plays a crucial role in this process, and protein conformational rearrangement can lead to changes in the size and characteristics of surrounding lipid domains.
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24
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Zhang S, Lin X. Lipid Acyl Chain cis Double Bond Position Modulates Membrane Domain Registration/Anti-Registration. J Am Chem Soc 2019; 141:15884-15890. [DOI: 10.1021/jacs.9b06977] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Siya Zhang
- Institute of Nanotechnology for Single Cell Analysis (INSCA), Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China
- State Key Laboratory of Medical Molecular Biology, School of Basic Medicine, Peking Union Medical College and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing 100005, China
| | - Xubo Lin
- Institute of Nanotechnology for Single Cell Analysis (INSCA), Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
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25
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Spontaneous and Stress-Induced Pore Formation in Membranes: Theory, Experiments and Simulations. J Membr Biol 2019; 252:241-260. [PMID: 31363808 DOI: 10.1007/s00232-019-00083-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/17/2019] [Indexed: 10/26/2022]
Abstract
The large plasticity, dynamics and adaptability of biological membranes allow different modes of intrinsic and inducible permeability. These phenomena are of physiological importance for a number of natural functions related to cell death and can also be manipulated artificially for practical purposes like gene transfer, drug delivery, prevention of infections or anticancer therapy. For these advances to develop in a controllable and specific way, we need a sufficient understanding of the membrane permeability phenomena. Since the formulation of early concepts of pore formation, there has been an enormous effort to describe membrane permeability by using theory, simulations and experiments. A major breakthrough has come recently through theoretical developments that allow building continuous trajectories of pore formation both in the absence and presence of stress conditions. The new model provides a coherent quantitative view of membrane permeabilization, useful to test the impact of known lipid properties, make predictions and postulate specific pore intermediates that can be studied by simulations. For example, this theory predicts unprecedented dependencies of the line tension on the pore radius and on applied lateral tension which explain previous puzzling results. In parallel, important concepts have also come from molecular dynamics simulations, of which the role of water for membrane permeabilization is of special interest. These advances open new challenges and perspectives for future progress in the study of membrane permeability, as experiments and simulations will need to test the theoretical predictions, while theory achieves new refinements that provide a physical ground for observations.
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26
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Vinklárek IS, Vel'as L, Riegerová P, Skála K, Mikhalyov I, Gretskaya N, Hof M, Šachl R. Experimental Evidence of the Existence of Interleaflet Coupled Nanodomains: An MC-FRET Study. J Phys Chem Lett 2019; 10:2024-2030. [PMID: 30964299 DOI: 10.1021/acs.jpclett.9b00390] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plasma membranes of living cells are compartmentalized into small submicroscopic structures (nanodomains) having potentially relevant biological functions. Despite this, structural features of these nanodomains remain elusive, primarily due to the difficulties in characterizing such small dynamic entities. It is unclear whether nanodomains found in the upper bilayer leaflet are transversally registered with those found in the lower leaflet. Experiments performed on larger microscopic domains indicate that the coupling between the leaflets is strong, forcing the domains to be in perfect registration, but can the same thing be said about the biologically more relevant nanodomains? This work provides experimental evidence that even small nanodomains of variable sizes between 10 and 160 nm are interleaflet coupled. Importantly, the alternative scenarios of partially registered, independent, or antiregistered nanodomains could be excluded.
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Affiliation(s)
- Ivo S Vinklárek
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
| | - Lukáš Vel'as
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
| | - Petra Riegerová
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
| | - Kristián Skála
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
- Department of Physical and Macromolecular Chemistry, Faculty of Science , Charles University , Hlavova 8 , CZ-12840 Prague , Czech Republic
| | - Ilya Mikhalyov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Science , Moscow GSP-7 , Russia
| | - Natalia Gretskaya
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Science , Moscow GSP-7 , Russia
| | - Martin Hof
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
| | - Radek Šachl
- Department of Biophysical Chemistry , J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences , 182 23 Prague , Czech Republic
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27
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Friedman R, Khalid S, Aponte-Santamaría C, Arutyunova E, Becker M, Boyd KJ, Christensen M, Coimbra JTS, Concilio S, Daday C, van Eerden FJ, Fernandes PA, Gräter F, Hakobyan D, Heuer A, Karathanou K, Keller F, Lemieux MJ, Marrink SJ, May ER, Mazumdar A, Naftalin R, Pickholz M, Piotto S, Pohl P, Quinn P, Ramos MJ, Schiøtt B, Sengupta D, Sessa L, Vanni S, Zeppelin T, Zoni V, Bondar AN, Domene C. Understanding Conformational Dynamics of Complex Lipid Mixtures Relevant to Biology. J Membr Biol 2018; 251:609-631. [PMID: 30350011 PMCID: PMC6244758 DOI: 10.1007/s00232-018-0050-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 10/03/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Ran Friedman
- Department of Chemistry and Biomedical Sciences and Centre of Excellence "Biomaterials Chemistry", Linnæus University, Kalmar, Sweden.
| | - Syma Khalid
- University of Southampton, Southampton, SO17 1BJ, UK
| | - Camilo Aponte-Santamaría
- Max Planck Tandem Group in Computational Biophysics, University of Los Andes, Bogotá, Colombia.,Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany
| | - Elena Arutyunova
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | | | - Kevin J Boyd
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Mikkel Christensen
- Department of Chemistry, Aarhus University, Aarhus, Denmark.,Interdisciplinary Nanoscience center (iNANO), Aarhus University, Aarhus, Denmark.,Sino-Danish Center for Education and Research, Beijing, China
| | - João T S Coimbra
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Simona Concilio
- Department of Industrial Engineering, University of Salerno, Fisciano, SA, Italy
| | - Csaba Daday
- Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | | | - Pedro A Fernandes
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Frauke Gräter
- Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany.,Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | | | | | - Konstantina Karathanou
- Department of Physics, Theoretical Molecular Biophysics Group, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | | | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | | | - Eric R May
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Antara Mazumdar
- GBB Institute, University of Groningen, Groningen, The Netherlands
| | - Richard Naftalin
- Physiology and Vascular Biology Departments, King's College London School of Medicine, London, UK
| | - Mónica Pickholz
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, CONICET-Universidad de Buenos Aires, IFIBA, Buenos Aires, Argentina
| | - Stefano Piotto
- Department of Pharmacy, University of Salerno, Fisciano, SA, Italy
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University, Linz, Austria
| | - Peter Quinn
- Biochemistry Department, King's College London, London, UK
| | - Maria J Ramos
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Birgit Schiøtt
- Department of Chemistry, Aarhus University, Aarhus, Denmark.,Interdisciplinary Nanoscience center (iNANO), Aarhus University, Aarhus, Denmark
| | - Durba Sengupta
- Physical Chemistry Division, National Chemical Laboratory, Pune, India
| | - Lucia Sessa
- Department of Pharmacy, University of Salerno, Fisciano, SA, Italy
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Talia Zeppelin
- Department of Chemistry, Aarhus University, Aarhus, Denmark
| | - Valeria Zoni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Ana-Nicoleta Bondar
- Department of Physics, Theoretical Molecular Biophysics Group, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | - Carmen Domene
- Department of Chemistry, University of Bath, Claverton Down Bath, BA2 7AY, UK.,Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
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28
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Kondrashov OV, Galimzyanov TR, Pavlov KV, Kotova EA, Antonenko YN, Akimov SA. Membrane Elastic Deformations Modulate Gramicidin A Transbilayer Dimerization and Lateral Clustering. Biophys J 2018; 115:478-493. [PMID: 30049405 PMCID: PMC6084527 DOI: 10.1016/j.bpj.2018.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 01/25/2023] Open
Abstract
Gramicidin A (gA) is a short β-helical peptide known to form conducting channels in lipid membranes because of transbilayer dimerization. The gA conducting dimer, being shorter than the lipid bilayer thickness, deforms the membrane in its vicinity, and the bilayer elastic energy contributes to the gA dimer formation energy. Likewise, membrane incorporation of a gA monomer, which is shorter than the lipid monolayer thickness, creates a void, thereby forcing surrounding lipid molecules to tilt to fill it. The energy of membrane deformation was calculated in the framework of the continuum elasticity theory, taking into account splay, tilt, lateral stretching/compression, Gaussian splay deformations, and external membrane tension. We obtained the interaction energy profiles for two gA monomers located either in the same or in the opposite monolayers. The profiles demonstrated the long-range attraction and short-range repulsion behavior of the monomers resulting from the membrane deformation. Analysis of the profile features revealed conditions under which clusters of gA monomers would not dissipate because of diffusion. The calculated dependence of the dimer formation and decay energy barriers on the membrane elastic properties was in good agreement with the available experimental data and suggested an explanation for a hitherto contentious phenomenon.
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Affiliation(s)
- Oleg V Kondrashov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia; Department of Theoretical Physics, Moscow Institute of Physics and Technology, Dolgoprudniy, Moscow Region, Russia
| | - Timur R Galimzyanov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia; Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS," Moscow, Russia
| | - Konstantin V Pavlov
- Laboratory of Electrophysiology, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russia
| | - Elena A Kotova
- Department of Photosynthesis and Fluorescence Research Methods, A. N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Yuri N Antonenko
- Laboratory of Membrane Biophysics, A. N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Sergey A Akimov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia; Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS," Moscow, Russia.
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Molotkovsky RJ, Alexandrova VV, Galimzyanov TR, Jiménez-Munguía I, Pavlov KV, Batishchev OV, Akimov SA. Lateral Membrane Heterogeneity Regulates Viral-Induced Membrane Fusion during HIV Entry. Int J Mol Sci 2018; 19:ijms19051483. [PMID: 29772704 PMCID: PMC5983600 DOI: 10.3390/ijms19051483] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 05/08/2018] [Accepted: 05/14/2018] [Indexed: 11/16/2022] Open
Abstract
Sphingomyelin- and cholesterol- enriched membrane domains, commonly referred to as “rafts” play a crucial role in a large number of intra- and intercellular processes. Recent experiments suggest that not only the volumetric inhomogeneity of lipid distribution in rafts, but also the arrangement of the 1D boundary between the raft and the surrounding membrane is important for the membrane-associated processes. The reason is that the boundary preferentially recruits different peptides, such as HIV (human immunodeficiency virus) fusion peptide. In the present work, we report a theoretical investigation of mechanisms of influence of the raft boundary arrangement upon virus-induced membrane fusion. We theoretically predict that the raft boundary can act as an attractor for viral fusion peptides, which preferentially distribute into the vicinity of the boundary, playing the role of ‘line active components’ of the membrane (‘linactants’). We have calculated the height of the fusion energy barrier and demonstrated that, in the case of fusion between HIV membrane and the target cell, presence of the raft boundary in the vicinity of the fusion site facilitates fusion. The results we obtained can be further generalized to be applicable to other enveloped viruses.
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Affiliation(s)
- Rodion J Molotkovsky
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia.
| | - Veronika V Alexandrova
- Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskie Gory, 119991 Moscow, Russia.
| | - Timur R Galimzyanov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia.
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", 4 Leninskiy Prospekt, 119049 Moscow, Russia.
| | - Irene Jiménez-Munguía
- Department of Engineering of Technological Equipment, National University of Science and Technology "MISiS", 4 Leninskiy Prospekt, 119049 Moscow, Russia.
| | - Konstantin V Pavlov
- Laboratory of Electrophysiology, Federal Clinical Center of Physical-Chemical Medicine of FMBA, 1a Malaya Pirogovskaya Street, 119435 Moscow, Russia.
| | - Oleg V Batishchev
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia.
- Department of Physics of Living Systems, Moscow Institute of Physics and Technology (State University), 9 Institutskiy Lane, Dolgoprudniy, 141700 Moscow Region, Russia.
| | - Sergey A Akimov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia.
- Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", 4 Leninskiy Prospekt, 119049 Moscow, Russia.
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30
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Baoukina S, Rozmanov D, Tieleman DP. Composition Fluctuations in Lipid Bilayers. Biophys J 2018; 113:2750-2761. [PMID: 29262367 PMCID: PMC5770567 DOI: 10.1016/j.bpj.2017.10.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 10/09/2017] [Accepted: 10/10/2017] [Indexed: 02/06/2023] Open
Abstract
Cell membranes contain multiple lipid and protein components having heterogeneous in-plane (lateral) distribution. Nanoscale rafts are believed to play an important functional role, but their phase state—domains of coexisting phases or composition fluctuations—is unknown. As a step toward understanding lateral organization of cell membranes, we investigate the difference between nanoscale domains of coexisting phases and composition fluctuations in lipid bilayers. We simulate model lipid bilayers with the MARTINI coarse-grained force field on length scales of tens of nanometers and timescales of tens of microseconds. We use a binary and a ternary mixture: a saturated and an unsaturated lipid, or a saturated lipid, an unsaturated lipid, and cholesterol, respectively. In these mixtures, the phase behavior can be tuned from a mixed state to a coexistence of a liquid-crystalline and a gel, or a liquid-ordered and a liquid-disordered phase. Transition from a two-phase to a one-phase state is achieved by raising the temperature and adding a hybrid lipid (with a saturated and an unsaturated chain). We analyze the evolution of bilayer properties along this transition: domains of two phases transform to fluctuations with local ordering and compositional demixing. Nanoscale domains and fluctuations differ in several properties, including interleaflet overlap and boundary length. Hybrid lipids show no enrichment at the boundary, but decrease the difference between the coexisting phases by ordering the disordered phase, which could explain their role in cell membranes.
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Affiliation(s)
- Svetlana Baoukina
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada
| | - Dmitri Rozmanov
- Department of Information Technologies, University of Calgary, Calgary, Alberta, Canada
| | - D Peter Tieleman
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada.
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31
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Switching between Successful and Dead-End Intermediates in Membrane Fusion. Int J Mol Sci 2017; 18:ijms18122598. [PMID: 29207481 PMCID: PMC5751201 DOI: 10.3390/ijms18122598] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/21/2017] [Accepted: 12/01/2017] [Indexed: 11/16/2022] Open
Abstract
Fusion of cellular membranes during normal biological processes, including proliferation, or synaptic transmission, is mediated and controlled by sophisticated protein machinery ensuring the preservation of the vital barrier function of the membrane throughout the process. Fusion of virus particles with host cell membranes is more sparingly arranged and often mediated by a single fusion protein, and the virus can afford to be less discriminative towards the possible different outcomes of fusion attempts. Formation of leaky intermediates was recently observed in some fusion processes, and an alternative trajectory of the process involving formation of π-shaped structures was suggested. In this study, we apply the methods of elasticity theory and Lagrangian formalism augmented by phenomenological and molecular geometry constraints and boundary conditions to investigate the traits of this trajectory and the drivers behind the choice of one of the possible scenarios depending on the properties of the system. The alternative pathway proved to be a dead end, and, depending on the parameters of the participating membranes and fusion proteins, the system can either reversibly enter the corresponding “leaky” configuration or be trapped in it. A parametric study in the biologically relevant range of variables emphasized the fusion protein properties crucial for the choice of the fusion scenario.
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32
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Akimov SA, Volynsky PE, Galimzyanov TR, Kuzmin PI, Pavlov KV, Batishchev OV. Pore formation in lipid membrane II: Energy landscape under external stress. Sci Rep 2017; 7:12509. [PMID: 28970526 PMCID: PMC5624950 DOI: 10.1038/s41598-017-12749-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 09/15/2017] [Indexed: 11/16/2022] Open
Abstract
Lipid membranes are extremely stable envelopes allowing cells to survive in various environments and to maintain desired internal composition. Membrane permeation through formation of transversal pores requires substantial external stress. Practically, pores are usually formed by application of lateral tension or transmembrane voltage. Using the same approach as was used for obtaining continuous trajectory of pore formation in the stress-less membrane in the previous article, we now consider the process of pore formation under the external stress. The waiting time to pore formation proved a non-monotonous function of the lateral tension, dropping from infinity at zero tension to a minimum at the tension of several millinewtons per meter. Transmembrane voltage, on the contrary, caused the waiting time to decrease monotonously. Analysis of pore formation trajectories for several lipid species with different spontaneous curvatures and elastic moduli under various external conditions provided instrumental insights into the mechanisms underlying some experimentally observed phenomena.
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Affiliation(s)
- Sergey A Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia. .,National University of Science and Technology "MISiS", 4 Leninskiy prospekt, Moscow, 119049, Russia.
| | - Pavel E Volynsky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow, 117997, Russia
| | - Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia.,National University of Science and Technology "MISiS", 4 Leninskiy prospekt, Moscow, 119049, Russia
| | - Peter I Kuzmin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia
| | - Konstantin V Pavlov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia.,Federal Research and Clinical Center of Physical-Chemical Medicine, 1a Malaya Pirogovskaya, Moscow, 119435, Russia
| | - Oleg V Batishchev
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow, 119071, Russia.,Moscow Institute of Physics and Technology, Institutsky lane 9, 141700, Dolgoprudniy, Russia
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33
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Akimov SA, Aleksandrova VV, Galimzyanov TR, Bashkirov PV, Batishchev OV. Interaction of amphipathic peptides mediated by elastic membrane deformations. BIOCHEMISTRY (MOSCOW), SUPPLEMENT SERIES A: MEMBRANE AND CELL BIOLOGY 2017. [DOI: 10.1134/s1990747817030035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Sun L, Böckmann RA. Membrane phase transition during heating and cooling: molecular insight into reversible melting. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2017; 47:151-164. [PMID: 28725998 DOI: 10.1007/s00249-017-1237-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/18/2017] [Accepted: 06/28/2017] [Indexed: 11/25/2022]
Abstract
With increasing temperature, lipid bilayers undergo a gel-fluid phase transition, which plays an essential role in many physiological phenomena. In the present work, this first-order phase transition was investigated for variable heating and cooling rates for a dipalmitoylphosphatidylcholine (DPPC) lipid bilayer by means of atomistic molecular dynamics simulations. Alternative methods to track the melting temperature [Formula: see text] are compared. The resulting [Formula: see text] is shown to be independent of the scan rate for small heating rates (0.05-0.3 K/ns) implying reversible melting, and increases for larger heating (0.3-4 K/ns) or cooling rates (2-0.1 K/ns). The reported dependency of the melting temperature on the heating rate is in perfect agreement with a two-state kinetic rate model as suggested previously. Expansion and shrinkage, as well as the dynamics of melting seeds is described. The simulations further exhibit a relative shift between melting seeds in opposing membrane leaflets as predicted from continuum elastic theory.
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Affiliation(s)
- Liping Sun
- Computational Biology, Department of Biology, Friedrich-Alexander-University of Erlangen-Nürnberg, Staudtstrasse 5, Erlangen, 91058, Germany
| | - Rainer A Böckmann
- Computational Biology, Department of Biology, Friedrich-Alexander-University of Erlangen-Nürnberg, Staudtstrasse 5, Erlangen, 91058, Germany.
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35
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Haataja MP. Lipid Domain Co-localization Induced by Membrane Undulations. Biophys J 2017; 112:655-662. [PMID: 28256225 DOI: 10.1016/j.bpj.2016.12.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/11/2016] [Accepted: 12/19/2016] [Indexed: 12/28/2022] Open
Abstract
Multicomponent lipid bilayer membranes display rich phase transition and associated compositional lipid domain formation behavior. When both leaflets of the bilayer contain domains, they are often found co-localized across the leaflets, implying the presence of a thermodynamic interleaflet coupling. In this work, it is demonstrated that fluctuation-induced interactions between domains embedded within opposing membrane leaflets provide a robust means to co-localize the domains. In particular, it is shown via a combination of a mode-counting argument, a perturbative calculation, and a non-perturbative treatment of a special case, that spatial variations in membrane bending rigidity associated with lipid domains embedded within the background phase always lead to an attractive interleaflet coupling with a magnitude of ∼0.01kBT/nm2 in simple model membrane systems. Finally, it is demonstrated that the fluctuation-induced coupling is very robust against membrane tension and substrate interactions.
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Affiliation(s)
- Mikko P Haataja
- Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey.
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36
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Galimzyanov TR, Kuzmin PI, Pohl P, Akimov SA. Undulations Drive Domain Registration from the Two Membrane Leaflets. Biophys J 2017; 112:339-345. [PMID: 28122219 DOI: 10.1016/j.bpj.2016.12.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/04/2016] [Accepted: 12/12/2016] [Indexed: 02/06/2023] Open
Abstract
Phase separation in biological membranes plays an important role in protein targeting and transmembrane signaling. Its occurrence in both membrane leaflets commonly gives rise to matching liquid or liquid-ordered domains in the opposing monolayers. The underlying mechanism of such co-localization is not fully understood. The decrease of the line tension around the thicker ordered domain constitutes an important driving force. Yet, robust domain coupling requires an additional energy source, which we have now identified as thermal undulations. Our theoretical analysis of elastic deformations in a lipid bilayer shows that stiffer lipid domains tend to distribute into areas with lower fluctuations of monolayer curvature. These areas naturally align in the opposing monolayers. Thus, coupling requires both membrane leafs to display a heterogeneity in splay rigidities. The heterogeneity may either originate from intrinsic lipid properties or be acquired by adsorption of peripheral molecules. Undulations and line tension act synergistically: the gain in energy due a minimized line tension is proportional to domain radius and thus primarily fuels the registration of smaller domains; whereas the energetic contribution of undulations increases with membrane area and thus primarily acts to coalesce larger domains.
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Affiliation(s)
- Timur R Galimzyanov
- Laboratory of Bioelectrochemistry, A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia; Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", Moscow, Russia
| | - Peter I Kuzmin
- Laboratory of Bioelectrochemistry, A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Peter Pohl
- Department of Molecular and Membrane Biophysics, Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Sergey A Akimov
- Laboratory of Bioelectrochemistry, A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia; Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", Moscow, Russia.
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37
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Galimzyanov TR, Lyushnyak AS, Aleksandrova VV, Shilova LA, Mikhalyov II, Molotkovskaya IM, Akimov SA, Batishchev OV. Line Activity of Ganglioside GM1 Regulates the Raft Size Distribution in a Cholesterol-Dependent Manner. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3517-3524. [PMID: 28324651 DOI: 10.1021/acs.langmuir.7b00404] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Liquid-ordered lipid domains, also called rafts, are assumed to be important players in different cellular processes, mainly signal transduction and membrane trafficking. They are thicker than the disordered part of the membrane and are thought to form to compensate for the hydrophobic mismatch between transmembrane proteins and the lipid environment. Despite the existence of such structures in vivo still being an open question, they are observed in model systems of multicomponent lipid bilayers. Moreover, the predictions obtained from model experiments allow the explanation of different physiological processes possibly involving rafts. Here we present the results of the study of the regulation of raft size distribution by ganglioside GM1. Combining atomic force microscopy with theoretical considerations based on the theory of membrane elasticity, we predict that this glycolipid should change the line tension of raft boundaries in two different ways, mainly depending on the cholesterol content. These results explain the shedding of gangliosides from the surface of tumor cells and the following ganglioside-induced apoptosis of T-lymphocytes in a raft-dependent manner. Moreover, the generality of the model allows the prediction of the line activity of different membrane components based on their molecular geometry.
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Affiliation(s)
- T R Galimzyanov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskii Prospekt, Moscow, 119071 Russia
- National University of Science and Technology "MISiS" , 4 Leninskii Prospekt, Moscow, 119049 Russia
| | - A S Lyushnyak
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskii Prospekt, Moscow, 119071 Russia
- Moscow Institute of Physics and Technology , 9 Institutskii per., Dolgoprudnyi, Moscow Region, 141700 Russia
| | - V V Aleksandrova
- National University of Science and Technology "MISiS" , 4 Leninskii Prospekt, Moscow, 119049 Russia
| | - L A Shilova
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskii Prospekt, Moscow, 119071 Russia
- Moscow Institute of Physics and Technology , 9 Institutskii per., Dolgoprudnyi, Moscow Region, 141700 Russia
| | - I I Mikhalyov
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya Str., Moscow, 117997 Russia
| | - I M Molotkovskaya
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya Str., Moscow, 117997 Russia
| | - S A Akimov
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskii Prospekt, Moscow, 119071 Russia
- National University of Science and Technology "MISiS" , 4 Leninskii Prospekt, Moscow, 119049 Russia
| | - O V Batishchev
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskii Prospekt, Moscow, 119071 Russia
- Moscow Institute of Physics and Technology , 9 Institutskii per., Dolgoprudnyi, Moscow Region, 141700 Russia
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38
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Rosetti CM, Montich GG, Pastorino C. Molecular Insight into the Line Tension of Bilayer Membranes Containing Hybrid Polyunsaturated Lipids. J Phys Chem B 2017; 121:1587-1600. [PMID: 28139120 DOI: 10.1021/acs.jpcb.6b10836] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Line tension (γ) is a key parameter for the structure and dynamics of membrane domains. It was proposed that hybrid lipids, with mixed saturated and unsaturated acyl chains, participate in the relaxation of γ through different mechanisms. In this work, we used molecular dynamics simulations of the coarse-grained MARTINI model to measure γ in liquid-ordered-liquid-disordered (Lo-Ld) membranes, with increasingly larger relative proportion of the hybrid polyunsaturated lipid PAPC (4:0-5:4PC) to DAPC (di5:4PC) (i.e., XH). We also calculated an elastic contribution to γ by the Lo-Ld thickness mismatch, tilt moduli, and bending moduli, as predicted by theory. We found that an increase in XH decreased the overall γ value and the elastic contribution to line tension. The effect on the elastic line tension is driven by a reduced hydrophobic mismatch. Changes in the elastic constants of the phases due to an increase in XH produced a slightly larger elastic γ term. In addition to this elastic energy, other major contributions to γ are found in these model membranes. Increasing XH decreases both elastic and nonelastic contributions to γ. Finally, PAPC also behaves as a linactant, relaxing γ through an interfacial effect, as predicted by theoretical results. This study gives insight into the actual contribution of distinct energy terms to γ in bilayers containing polyunsaturated hybrid lipids.
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Affiliation(s)
- Carla M Rosetti
- Centro de Química Biológica de Córdoba, CIQUIBIC, Departamento de Química Biológica, Facultad de Ciencias Químicas, CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA, Córdoba, Argentina
| | - Guillermo G Montich
- Centro de Química Biológica de Córdoba, CIQUIBIC, Departamento de Química Biológica, Facultad de Ciencias Químicas, CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA, Córdoba, Argentina
| | - Claudio Pastorino
- Departamento de Física, Centro Atómico Constituyentes CNEA , Av. Gral. Paz 1499, 1650 San Martín, Buenos Aires, Argentina.,CONICET , Avda. Rivadavia 1917, C1033AAJ Cdad. de Buenos Aires, Buenos Aires, Argentina
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39
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Min Y. Phase dynamics and domain interactions in biological membranes. Curr Opin Chem Eng 2017. [DOI: 10.1016/j.coche.2016.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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40
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Fujimoto T, Parmryd I. Interleaflet Coupling, Pinning, and Leaflet Asymmetry-Major Players in Plasma Membrane Nanodomain Formation. Front Cell Dev Biol 2017; 4:155. [PMID: 28119914 PMCID: PMC5222840 DOI: 10.3389/fcell.2016.00155] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 12/27/2016] [Indexed: 01/26/2023] Open
Abstract
The plasma membrane has a highly asymmetric distribution of lipids and contains dynamic nanodomains many of which are liquid entities surrounded by a second, slightly different, liquid environment. Contributing to the dynamics is a continuous repartitioning of components between the two types of liquids and transient links between lipids and proteins, both to extracellular matrix and cytoplasmic components, that temporarily pin membrane constituents. This make plasma membrane nanodomains exceptionally challenging to study and much of what is known about membrane domains has been deduced from studies on model membranes at equilibrium. However, living cells are by definition not at equilibrium and lipids are distributed asymmetrically with inositol phospholipids, phosphatidylethanolamines and phosphatidylserines confined mostly to the inner leaflet and glyco- and sphingolipids to the outer leaflet. Moreover, each phospholipid group encompasses a wealth of species with different acyl chain combinations whose lateral distribution is heterogeneous. It is becoming increasingly clear that asymmetry and pinning play important roles in plasma membrane nanodomain formation and coupling between the two lipid monolayers. How asymmetry, pinning, and interdigitation contribute to the plasma membrane organization is only beginning to be unraveled and here we discuss their roles and interdependence.
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Affiliation(s)
- Toyoshi Fujimoto
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine Nagoya, Japan
| | - Ingela Parmryd
- Science for Life Laboratory, Medical Cell Biology, Uppsala University Uppsala, Sweden
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41
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Bocharov EV, Mineev KS, Pavlov KV, Akimov SA, Kuznetsov AS, Efremov RG, Arseniev AS. Helix-helix interactions in membrane domains of bitopic proteins: Specificity and role of lipid environment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1859:561-576. [PMID: 27884807 DOI: 10.1016/j.bbamem.2016.10.024] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/18/2016] [Accepted: 10/20/2016] [Indexed: 12/23/2022]
Abstract
Interaction between transmembrane helices often determines biological activity of membrane proteins. Bitopic proteins, a broad subclass of membrane proteins, form dimers containing two membrane-spanning helices. Some aspects of their structure-function relationship cannot be fully understood without considering the protein-lipid interaction, which can determine the protein conformational ensemble. Experimental and computer modeling data concerning transmembrane parts of bitopic proteins are reviewed in the present paper. They highlight the importance of lipid-protein interactions and resolve certain paradoxes in the behavior of such proteins. Besides, some properties of membrane organization provided a clue to understanding of allosteric interactions between distant parts of proteins. Interactions of these kinds appear to underlie a signaling mechanism, which could be widely employed in the functioning of many membrane proteins. Treatment of membrane proteins as parts of integrated fine-tuned proteolipid system promises new insights into biological function mechanisms and approaches to drug design. This article is part of a Special Issue entitled: Lipid order/lipid defects and lipid-control of protein activity edited by Dirk Schneider.
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Affiliation(s)
- Eduard V Bocharov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation; National Research Centre "Kurchatov Institute", Akad. Kurchatova pl. 1, Moscow, 123182, Russian Federation.
| | - Konstantin S Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation
| | - Konstantin V Pavlov
- Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninskiy prospect 31/5, Moscow, 119071, Russian Federation
| | - Sergey A Akimov
- Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninskiy prospect 31/5, Moscow, 119071, Russian Federation; National University of Science and Technology "MISiS", Leninskiy prospect 4, Moscow, 119049, Russian Federation
| | - Andrey S Kuznetsov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation; Higher School of Economics, Myasnitskaya ul. 20, Moscow, 101000, Russian Federation
| | - Alexander S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation.
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42
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Kheyfets B, Galimzyanov T, Drozdova A, Mukhin S. Analytical calculation of the lipid bilayer bending modulus. Phys Rev E 2016; 94:042415. [PMID: 27841551 DOI: 10.1103/physreve.94.042415] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Indexed: 11/07/2022]
Abstract
Bending and Gaussian moduli of a homogenious single-component lipid bilayer are calculated analytically using microscopic model of the lipid hydrocarbon chains. The approach allows for thermodynamic averaging over different chains conformations. Each chain is modeled as a flexible string with finite bending rigidity and an incompressible cross-section area. The interchain steric repulsion is accounted for self-consistently determined single-chain confining parabolic potential. The model provides a simple analytical expression for the membrane bending modulus, which falls within a range of experimental values. An observed dependence of the modulus on hydrocarbon chain length is also reproduced. Correspondence between our microscopic model and the membrane theory of elasticity is established.
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Affiliation(s)
- Boris Kheyfets
- National University of Science and Technology MISIS, Leninskiy prospekt 4, Moscow 119049, Russia
| | - Timur Galimzyanov
- National University of Science and Technology MISIS, Leninskiy prospekt 4, Moscow 119049, Russia
| | - Anna Drozdova
- National University of Science and Technology MISIS, Leninskiy prospekt 4, Moscow 119049, Russia
| | - Sergei Mukhin
- National University of Science and Technology MISIS, Leninskiy prospekt 4, Moscow 119049, Russia
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43
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Lin X, Zhang S, Ding H, Levental I, Gorfe AA. The aliphatic chain of cholesterol modulates bilayer interleaflet coupling and domain registration. FEBS Lett 2016; 590:3368-3374. [PMID: 27590031 DOI: 10.1002/1873-3468.12383] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/25/2016] [Accepted: 08/29/2016] [Indexed: 11/10/2022]
Abstract
Cholesterol is a necessary component and critical regulator of liquid-ordered membrane domains. However, the structural features that determine its unique physicochemical behaviors are not fully understood. In particular, very little is known about the specific functions of the terminal aliphatic chain of cholesterol, as previous studies have focused mainly on the rigid sterol ring structure and its hydroxyl head. In the current work, we used coarse-grained molecular dynamics simulations to investigate the effect of cholesterol aliphatic chain length on the dynamics and structure of coexisting lipid domains. We found that the aliphatic chain has no appreciable effect on phase separation per se, but it significantly affects the rate of cholesterol flip-flop and intermonolayer interaction. These effects are accompanied by changes in domain dynamics, lateral pressure, and interleaflet coupling. Our study provides useful insight into how biological sterols modulate communication between the outer and inner surfaces of the plasma membrane and, therefore, cellular signaling.
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Affiliation(s)
- Xubo Lin
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Texas 77030, USA
| | - Siya Zhang
- State Key Laboratory of Medical Molecular Biology, School of Basic Medicine, Peking Union Medical College and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing 100005, China.,Department of Immunology, The University of Texas MD Anderson Cancer Center, Texas 77054, USA
| | - Hui Ding
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Texas 77030, USA.,Department of Respiratory Medicine, Yixing Hospital affiliated Jiangsu University, Jiangsu 214200, China
| | - Ilya Levental
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Texas 77030, USA
| | - Alemayehu A Gorfe
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Texas 77030, USA
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44
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Blosser MC, Honerkamp-Smith AR, Han T, Haataja M, Keller SL. Transbilayer Colocalization of Lipid Domains Explained via Measurement of Strong Coupling Parameters. Biophys J 2016; 109:2317-27. [PMID: 26636943 DOI: 10.1016/j.bpj.2015.10.031] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 10/16/2015] [Accepted: 10/26/2015] [Indexed: 01/03/2023] Open
Abstract
When micron-scale compositional heterogeneity develops in membranes, the distribution of lipids on one face of the membrane strongly affects the distribution on the other. Specifically, when lipid membranes phase separate into coexisting liquid phases, domains in each monolayer leaflet of the membrane are colocalized with domains in the opposite leaflet. Colocalized domains have never been observed to spontaneously move out of registry. This result indicates that the lipid compositions in one leaflet are strongly coupled to compositions in the opposing leaflet. Predictions of the interleaflet coupling parameter, Λ, vary by a factor of 50. We measure the value of Λ by applying high shear forces to supported lipid bilayers. This causes the upper leaflet to slide over the lower leaflet, moving domains out of registry. We find that the threshold shear stress required to deregister domains in the upper and lower leaflets increases with the inverse length of domains. We derive a simple, closed-form expression relating the threshold shear to Λ, and find Λ = 0.016 ± 0.004 kBT/nm2.
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Affiliation(s)
- Matthew C Blosser
- Departments of Chemistry and Physics, University of Washington, Seattle, Washington
| | - Aurelia R Honerkamp-Smith
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, United Kingdom
| | - Tao Han
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey
| | - Mikko Haataja
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey
| | - Sarah L Keller
- Departments of Chemistry and Physics, University of Washington, Seattle, Washington.
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45
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Fowler PW, Williamson JJ, Sansom MSP, Olmsted PD. Roles of Interleaflet Coupling and Hydrophobic Mismatch in Lipid Membrane Phase-Separation Kinetics. J Am Chem Soc 2016; 138:11633-42. [PMID: 27574865 PMCID: PMC5025830 DOI: 10.1021/jacs.6b04880] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
![]()
Characterizing
the nanoscale dynamic organization within lipid
bilayer
membranes is central
to our understanding of cell membranes at a molecular level. We investigate
phase separation and communication across leaflets in ternary lipid
bilayers, including saturated lipids with between 12 and 20 carbons
per tail. Coarse-grained molecular dynamics simulations reveal a novel
two-step kinetics due to hydrophobic mismatch, in which the initial
response of the apposed leaflets upon quenching is to increase local
asymmetry (antiregistration), followed by dominance of symmetry (registration)
as the bilayer equilibrates. Antiregistration can become thermodynamically
preferred if domain size is restricted below ∼20 nm, with implications
for the symmetry of rafts and nanoclusters in cell membranes, which
have similar reported sizes. We relate our findings to theory derived
from a semimicroscopic model in which the leaflets experience a “direct”
area-dependent coupling, and an “indirect” coupling
that arises from hydrophobic mismatch and is most important at domain
boundaries. Registered phases differ in composition from antiregistered
phases, consistent with a direct coupling between the leaflets. Increased
hydrophobic mismatch purifies the phases, suggesting that it contributes
to the molecule-level lipid immiscibility. Our results demonstrate
an interplay of competing interleaflet couplings that affect phase
compositions and kinetics, and lead to a length scale that
can influence lateral and transverse bilayer organization within cells.
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Affiliation(s)
- Philip W Fowler
- Department of Biochemistry, University of Oxford , South Parks Road, Oxford, OX1 3QU, U.K
| | - John J Williamson
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University , 37th and O Streets, N.W., Washington, D.C. 20057, United States
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford , South Parks Road, Oxford, OX1 3QU, U.K
| | - Peter D Olmsted
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University , 37th and O Streets, N.W., Washington, D.C. 20057, United States
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46
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Tian J, Nickels J, Katsaras J, Cheng X. Behavior of Bilayer Leaflets in Asymmetric Model Membranes: Atomistic Simulation Studies. J Phys Chem B 2016; 120:8438-48. [DOI: 10.1021/acs.jpcb.6b02148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - John Katsaras
- The Bredesen Center for Interdisciplinary Research and Graduate Education, 444 Greve Hall, 821 Volunteer Boulevard, Knoxville, Tennessee 37996-3394, United States
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47
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Galimzyanov TR, Kuzmin PI, Pohl P, Akimov SA. Elastic deformations of bolalipid membranes. SOFT MATTER 2016; 12:2357-64. [PMID: 26791255 PMCID: PMC7116075 DOI: 10.1039/c5sm02635k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Archaeal membranes have unique mechanical properties that enable these organisms to survive under extremely aggressive environmental conditions. The so-called bolalipids contribute to this exceptional stability. They have two polar heads joined by two hydrocarbon chains. The two headgroups can face different sides of the membrane (O-shape conformation) or the same side (U-shape conformation). We have developed an elasticity theory for bolalipid membranes and show that the energetic contributions of (i) tilt deformations, (ii) area compression/stretching deformations, (iii) as well as those of Gaussian splay from the two membrane surfaces are additive, while splay deformations yield a cross-term. The presence of a small fraction of U-shaped molecules resulted in spontaneous membrane curvature. We estimated the tilt modulus to be approximately equal to that of membranes in eukaryotic cells. In contrast to conventional lipids, the bolalipid membrane possesses two splay moduli, one of which is estimated to be an order of magnitude larger than that of conventional lipids. The projected values of elastic moduli act to hamper pore formation and to decelerate membrane fusion and fission.
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Affiliation(s)
- Timur R Galimzyanov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia. and Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", 4 Leninskiy Prospect, Moscow 119049, Russia
| | - Peter I Kuzmin
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia.
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40-42, Linz, 4020, Austria
| | - Sergey A Akimov
- Laboratory of Bioelectrochemistry, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, Moscow 119071, Russia. and Department of Theoretical Physics and Quantum Technologies, National University of Science and Technology "MISiS", 4 Leninskiy Prospect, Moscow 119049, Russia
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48
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Williamson JJ, Olmsted PD. Comment on "Elastic Membrane Deformations Govern Interleaflet Coupling of Lipid-Ordered Domains". PHYSICAL REVIEW LETTERS 2016; 116:079801. [PMID: 26943562 DOI: 10.1103/physrevlett.116.079801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Indexed: 06/05/2023]
Affiliation(s)
- J J Williamson
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets N.W., Washington, D.C. 20057, USA
| | - P D Olmsted
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets N.W., Washington, D.C. 20057, USA
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49
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Galimzyanov TR, Molotkovsky RJ, Cohen FS, Pohl P, Akimov SA. Galimzyanov et al. Reply. PHYSICAL REVIEW LETTERS 2016; 116:079802. [PMID: 26943563 PMCID: PMC4815921 DOI: 10.1103/physrevlett.116.079802] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 05/10/2023]
Affiliation(s)
- Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy prospekt, Moscow 119071, Russia
- National University of Science and Technology "MISiS", 4 Leninskiy prospekt, Moscow 119049, Russia
| | - Rodion J Molotkovsky
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy prospekt, Moscow 119071, Russia
| | - Fredric S Cohen
- Rush University Medical Center, 1750 W. Harrison Street, Chicago, Illinois 60612, USA
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstr. 40-42, Linz 4020, Austria
| | - Sergey A Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/5 Leninskiy prospekt, Moscow 119071, Russia
- National University of Science and Technology "MISiS", 4 Leninskiy prospekt, Moscow 119049, Russia
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50
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Staneva G, Osipenko DS, Galimzyanov TR, Pavlov KV, Akimov SA. Metabolic Precursor of Cholesterol Causes Formation of Chained Aggregates of Liquid-Ordered Domains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:1591-1600. [PMID: 26783730 DOI: 10.1021/acs.langmuir.5b03990] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
7-Dehydrocholesterol, an immediate metabolic predecessor of cholesterol, can accumulate in tissues due to some metabolic abnormalities, causing an array of symptoms known as Smith-Lemli-Opitz syndrome. Enrichment of cellular membranes with 7-dehydrocholesterol interferes with normal cell-signaling processes, which involve interaction between rafts and formation of the so-called signaling platforms. In model membranes, cholesterol-based ordered domains usually merge upon contact. According to our experimental data, ordered domains in the model systems where cholesterol is substituted for 7-dehydrocholesterol never merge on the time scale of the experiment, but clusterize into necklace-like aggregates. We attribute such different dynamical behavior to altered properties of the domain boundary. In the framework of thickness mismatch model, we analyzed changes of interaction energy profiles of two approaching domains caused by substitution of cholesterol by 7-dehydrocholesterol. The energy barrier for domain merger is shown to increase notably, with simultaneous appearance of another distinct local energy minimum. Such energy profile is in perfect qualitative agreement with the experimental observations. The observed change of domain dynamics can impair proper interaction between cellular rafts underlying pathologies associated with deviations in cholesterol metabolism.
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Affiliation(s)
- Galya Staneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences , 21 Academic G. Bonchev Str., Sofia 1113, Bulgaria
| | - Denis S Osipenko
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Timur R Galimzyanov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskiy prospekt, Moscow 119071, Russia
- National University of Science and Technology "MISiS" , 4 Leninskiy prospect, Moscow 119049, Russia
| | - Konstantin V Pavlov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskiy prospekt, Moscow 119071, Russia
| | - Sergey A Akimov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences , 31/4 Leninskiy prospekt, Moscow 119071, Russia
- National University of Science and Technology "MISiS" , 4 Leninskiy prospect, Moscow 119049, Russia
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