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Kataoka-Hamai C. Triacylglycerol-droplet-induced bilayer spontaneous curvature in giant unilamellar vesicles. Biophys J 2024; 123:1857-1868. [PMID: 38822522 DOI: 10.1016/j.bpj.2024.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/05/2024] [Accepted: 05/29/2024] [Indexed: 06/03/2024] Open
Abstract
This study investigated the incorporation of triacylglycerol droplets in the bilayers of giant unilamellar vesicles (GUVs) using four triacylglycerols and four phosphatidylcholines by confocal laser scanning microscopy. The triacylglycerol droplets were incorporated between the monolayer leaflets of the GUVs. Among the spherical droplets protruding on only one side of the bilayers, the droplets bound to the outer leaflets outnumbered those bound to the inner leaflets. The more frequent droplet binding to the outer leaflet caused transbilayer asymmetry in the droplet surface density. A vesicle consisting of a single-bilayer spherical segment and a double-bilayer spherical segment was also observed. The yield of these vesicles was comparable with or higher than that of the droplet-incorporating GUVs for many of the phosphatidylcholine-triacylglycerol combinations. In a vesicle consisting of single-bilayer and double-bilayer segments, most of the triacylglycerol droplets were localized on the outermost membrane surface along the segment boundary and in the double-bilayer segment. To rationalize the formation of these vesicle structures, we propose that the transbilayer asymmetry in the droplet surface density induces spontaneous curvature of the bilayer, with the bilayer spontaneously bending away from the droplets. Energy calculations performed assuming the existence of spontaneous curvature of the bilayer corroborated the experimentally determined membrane shapes for the vesicles consisting of unilamellar and bilamellar regions.
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Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan.
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2
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Weakly HMJ, Wilson KJ, Goetz GJ, Pruitt EL, Li A, Xu L, Keller SL. Several common methods of making vesicles (except an emulsion method) capture intended lipid ratios. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.21.581444. [PMID: 38948736 PMCID: PMC11212916 DOI: 10.1101/2024.02.21.581444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Researchers choose different methods of making giant unilamellar vesicles in order to satisfy different constraints of their experimental designs. A challenge of using a variety of methods is that each may produce vesicles of different lipid compositions, even if all vesicles are made from a common stock mixture. Here, we use mass spectrometry to investigate ratios of lipids in vesicles made by five common methods: electroformation on indium tin oxide slides, electroformation on platinum wires, gentle hydration, emulsion transfer, and extrusion. We made vesicles from either 5-component or binary mixtures of lipids chosen to span a wide range of physical properties: di(18:1)PC, di(16:0)PC, di(18:1)PG, di(12:0)PE, and cholesterol. For a mixture of all five of these lipids, ITO electroformation, Pt electroformation, gentle hydration, and extrusion methods result in only minor shifts (≤ 5 mol%) in lipid ratios of vesicles relative to a common stock solution. In contrast, emulsion transfer results in ∼80% less cholesterol than expected from the stock solution, which is counterbalanced by a surprising overabundance of saturated PC-lipid relative to all other phospholipids. Experiments using binary mixtures of some of the lipids largely support results from the 5-component mixture. Exact values of lipid ratios variations likely depend on the details of each method, so a broader conclusion is that experiments that increment lipid ratios in small steps will be highly sensitive to the method of lipid formation and to sample-to-sample variations, which are low (roughly ±2 mol% in the 5-component mixture and either scale proportionally with increasing mole fraction or remain low). Experiments that increment lipid ratios in larger steps or that seek to explain general trends or new phenomena will be less sensitive to the method used. SIGNIFICANCE STATEMENT Small changes to the amounts and types of lipids in membranes can drastically affect the membrane's behavior. Unfortunately, it is unknown whether (or to what extent) different methods of making vesicles alter the ratios of lipids in membranes, even when identical stock solutions are used. This presents challenges for researchers when comparing data with colleagues who use different methods. Here, we measure ratios of lipid types in vesicle membranes produced by five methods. We assess each method's reproducibility and compare resulting vesicle compositions across methods. In doing so, we provide a quantitative basis that the scientific community can use to estimate whether differences between their results can be simply attributed to differences between methods or to sample-to-sample variations.
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3
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Mardešić I, Boban Z, Raguz M. Electroformation of Giant Unilamellar Vesicles from Damp Lipid Films with a Focus on Vesicles with High Cholesterol Content. MEMBRANES 2024; 14:79. [PMID: 38668107 PMCID: PMC11051717 DOI: 10.3390/membranes14040079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/20/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
Giant unilamellar vesicles (GUVs) are membrane models used to study membrane properties. Electroformation is one of the methods used to produce GUVs. During electroformation protocol, dry lipid film is formed. The drying of the lipid film induces the cholesterol (Chol) demixing artifact, in which Chol forms anhydrous crystals which do not participate in the formation of vesicles. This leads to a lower Chol concentration in the vesicle bilayers compared to the Chol concentration in the initial lipid solution. To address this problem, we propose a novel electroformation protocol that includes rapid solvent exchange (RSE), plasma cleaning, and spin-coating methods to produce GUVs. We tested the protocol, focusing on vesicles with a high Chol content using different spin-coating durations and vesicle type deposition. Additionally, we compared the novel protocol using completely dry lipid film. The optimal spin-coating duration for vesicles created from the phosphatidylcholine/Chol mixture was 30 s. Multilamellar vesicles (MLVs), large unilamellar vesicles (LUVs) obtained by the extrusion of MLVs through 100 nm membrane pores and LUVs obtained by extrusion of previously obtained LUVs through 50 nm membrane pores, were deposited on an electrode for 1.5/1 Chol/phosphatidylcholine (POPC) lipid mixture, and the results were compared. Electroformation using all three deposited vesicle types resulted in a high GUV yield, but the deposition of LUVs obtained by the extrusion of MLVs through 100 nm membrane pores provided the most reproducible results. Using the deposition of these LUVs, we produced high yield GUVs for six different Chol concentrations (from 0% to 71.4%). Using a protocol that included dry lipid film GUVs resulted in lower yields and induced the Chol demixing artifact, proving that the lipid film should never be subjected to drying when the Chol content is high.
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Affiliation(s)
- Ivan Mardešić
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (I.M.); (Z.B.)
- Doctoral Study of Biophysics, Faculty of Science, University of Split, 21000 Split, Croatia
| | - Zvonimir Boban
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (I.M.); (Z.B.)
| | - Marija Raguz
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (I.M.); (Z.B.)
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4
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Otrin N, Otrin L, Bednarz C, Träger TK, Hamdi F, Kastritis PL, Ivanov I, Sundmacher K. Protein-Rich Rafts in Hybrid Polymer/Lipid Giant Unilamellar Vesicles. Biomacromolecules 2024; 25:778-791. [PMID: 38190609 PMCID: PMC10865357 DOI: 10.1021/acs.biomac.3c00972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/20/2023] [Accepted: 12/20/2023] [Indexed: 01/10/2024]
Abstract
Considerable attention has been dedicated to lipid rafts due to their importance in numerous cell functions such as membrane trafficking, polarization, and signaling. Next to studies in living cells, artificial micrometer-sized vesicles with a minimal set of components are established as a major tool to understand the phase separation dynamics and their intimate interplay with membrane proteins. In parallel, mixtures of phospholipids and certain amphiphilic polymers simultaneously offer an interface for proteins and mimic this segregation behavior, presenting a tangible synthetic alternative for fundamental studies and bottom-up design of cellular mimics. However, the simultaneous insertion of complex and sensitive membrane proteins is experimentally challenging and thus far has been largely limited to natural lipids. Here, we present the co-reconstitution of the proton pump bo3 oxidase and the proton consumer ATP synthase in hybrid polymer/lipid giant unilamellar vesicles (GUVs) via fusion/electroformation. Variations of the current method allow for tailored reconstitution protocols and control of the vesicle size. In particular, mixing of protein-free and protein-functionalized nanosized vesicles in the electroformation film results in larger GUVs, while separate reconstitution of the respiratory enzymes enables higher ATP synthesis rates. Furthermore, protein labeling provides a synthetic mechanism for phase separation and protein sequestration, mimicking lipid- and protein-mediated domain formation in nature. The latter means opens further possibilities for re-enacting phenomena like supercomplex assembly or symmetry breaking and enriches the toolbox of bottom-up synthetic biology.
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Affiliation(s)
- Nika Otrin
- Process
Systems Engineering, Max Planck Institute
for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
| | - Lado Otrin
- Process
Systems Engineering, Max Planck Institute
for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
| | - Claudia Bednarz
- Process
Systems Engineering, Max Planck Institute
for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
| | - Toni K. Träger
- Interdisciplinary
Research Center HALOmem and Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, 06120 Halle/Saale, Germany
| | - Farzad Hamdi
- Interdisciplinary
Research Center HALOmem and Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, 06120 Halle/Saale, Germany
| | - Panagiotis L. Kastritis
- Interdisciplinary
Research Center HALOmem and Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, 06120 Halle/Saale, Germany
- Institute
of Chemical Biology, National Hellenic Research
Foundation, 11635 Athens, Greece
| | - Ivan Ivanov
- Process
Systems Engineering, Max Planck Institute
for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
- Grup
de Biotecnologia Molecular i Industrial, Department of Chemical Engineering, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, 08222 Terrassa, Spain
| | - Kai Sundmacher
- Process
Systems Engineering, Max Planck Institute
for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany
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5
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Kumar R, Dzikonski D, Bekker E, Vornhusen R, Vitali V, Imbrock J, Denz C. Fabrication and mechanical characterization of hydrogel-based 3D cell-like structures. OPTICS EXPRESS 2023; 31:29174-29186. [PMID: 37710723 DOI: 10.1364/oe.496888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 07/27/2023] [Indexed: 09/16/2023]
Abstract
In this article, we demonstrate the fabrication of 3D cell-like structures using a femtosecond laser-based two-photon polymerization technique. By employing poly(ethylene glycol) diacrylate monomers as a precursor solution, we fabricate 3D hemispheres that resemble morphological and biomechanical characteristics of natural cells. We employ an optical tweezers-based microrheology technique to measure the viscoelastic properties of the precursor solutions inside and outside the structures. In addition, we demonstrate the interchangeability of the precursor solution within fabricated structures without impairing the microstructures. The combination of two-photon polymerization and microrheological measurements by optical tweezers demonstrated here represents a powerful toolbox for future investigations into cell mimic and artificial cell studies.
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6
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Nair KS, Bajaj H. Advances in giant unilamellar vesicle preparation techniques and applications. Adv Colloid Interface Sci 2023; 318:102935. [PMID: 37320960 DOI: 10.1016/j.cis.2023.102935] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 05/23/2023] [Accepted: 06/05/2023] [Indexed: 06/17/2023]
Abstract
Giant unilamellar vesicles (GUVs) are versatile and promising cell-sized bio-membrane mimetic platforms. Their applications range from understanding and quantifying membrane biophysical processes to acting as elementary blocks in the bottom-up assembly of synthetic cells. Definite properties and requisite goals in GUVs are dictated by the preparation techniques critical to the success of their applications. Here, we review key advances in giant unilamellar vesicle preparation techniques and discuss their formation mechanisms. Developments in lipid hydration and emulsion techniques for GUV preparation are described. Novel microfluidic-based techniques involving lipid or surfactant-stabilized emulsions are outlined. GUV immobilization strategies are summarized, including gravity-based settling, covalent linking, and immobilization by microfluidic, electric, and magnetic barriers. Moreover, some of the key applications of GUVs as biomimetic and synthetic cell platforms during the last decade have been identified. Membrane interface processes like phase separation, membrane protein reconstitution, and membrane bending have been deciphered using GUVs. In addition, vesicles are also employed as building blocks to construct synthetic cells with defined cell-like functions comprising compartments, metabolic reactors, and abilities to grow and divide. We critically discuss the pros and cons of preparation technologies and the properties they confer to the GUVs and identify potential techniques for dedicated applications.
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Affiliation(s)
- Karthika S Nair
- Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre, Ghaziabad 201002, India
| | - Harsha Bajaj
- Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre, Ghaziabad 201002, India.
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7
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Esteruelas G, Ortiz A, Prat J, Vega E, Muñoz-Juncosa M, López MLG, Ettcheto M, Camins A, Sánchez-López E, Pujol M. Novel customized age-dependent corneal membranes and interactions with biodegradable nanoparticles loaded with dexibuprofen. Colloids Surf B Biointerfaces 2023; 228:113394. [PMID: 37301018 DOI: 10.1016/j.colsurfb.2023.113394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 06/01/2023] [Accepted: 06/04/2023] [Indexed: 06/12/2023]
Abstract
Ocular inflammation is one of the most prevalent diseases in ophthalmology and it is currently treated using eye drops of nonsteroidal antiinflammatory drugs such as dexibuprofen (DXI). However, their bioavailability is low and therefore, PLGA nanoparticles constitute a suitable approach to be administered as eyedrops. Therefore, DXI has been encapsulated into PLGA nanoparticles (DXI-NPs). Although the eye, and specifically the cornea, suffers from age-related changes in its composition, current medications are not focused on these variations. Therefore, to elucidate the interaction mechanism of DXI-NPs with the cornea in relation with age, two different corneal membrane models have been developed (corresponding to adult and elder population) using lipid monolayers, large and giant unilamellar vesicles. Interactions of both DXI and DXI-NPs were studied with these models by means of Langmuir balance technique, dipole potential, anisotropy and confocal microscopy. In addition, fluorescently labelled nanoparticles were administered to mice in order to corroborate these data obtained in vitro. It was observed that DXI-NPs interact with lipid membranes through an adhesion process, mainly in the rigid regions and afterwards DXI-NPs are internalized by a wrapping process. Furthermore, differences on the dipole potential caused by DXI-NPs in each corneal membrane have been obtained due to the increase of membrane rigidity on the ECMM. Additionally, it can be confirmed that DXI-NPs adhere to Lo phase and also inside the lipid membrane. Finally, in vitro and in vivo results corroborate that DXI-NPs are adhered to the more ordered phase. Finally, differences between interactions of DXI-NPs with the elder and adult corneal tissue were observed.
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Affiliation(s)
- Gerard Esteruelas
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Alba Ortiz
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Josefina Prat
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Estefania Vega
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Montserrat Muñoz-Juncosa
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Maria Luisa Garcia López
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain; Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Miren Ettcheto
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Center for Biomedical Research in Neurodegenerative Diseases Network (CIBERNED), Carlos III Health Institute, 28031 Madrid, Spain
| | - Antoni Camins
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Center for Biomedical Research in Neurodegenerative Diseases Network (CIBERNED), Carlos III Health Institute, 28031 Madrid, Spain
| | - Elena Sánchez-López
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain; Center for Biomedical Research in Neurodegenerative Diseases Network (CIBERNED), Carlos III Health Institute, 28031 Madrid, Spain; Unit of Synthesis and Biomedical Applications of Peptides, IQAC-CSIC, 08034 Barcelona, Spain.
| | - Montserrat Pujol
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain.
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8
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Boban Z, Mardešić I, Jozić SP, Šumanovac J, Subczynski WK, Raguz M. Electroformation of Giant Unilamellar Vesicles from Damp Lipid Films Formed by Vesicle Fusion. MEMBRANES 2023; 13:352. [PMID: 36984739 PMCID: PMC10059949 DOI: 10.3390/membranes13030352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 06/18/2023]
Abstract
Giant unilamellar vesicles (GUVs) are artificial membrane models which are of special interest to researchers because of their similarity in size to eukaryotic cells. The most commonly used method for GUVs production is electroformation. However, the traditional electroformation protocol involves a step in which the organic solvent is completely evaporated, leaving behind a dry lipid film. This leads to artifactual demixing of cholesterol (Chol) in the form of anhydrous crystals. These crystals do not participate in the formation of the lipid bilayer, resulting in a decrease of Chol concentration in the bilayer compared to the initial lipid solution. We propose a novel electroformation protocol which addresses this issue by combining the rapid solvent exchange, plasma cleaning and spin-coating techniques to produce GUVs from damp lipid films in a fast and reproducible manner. We have tested the protocol efficiency using 1/1 phosphatidylcholine/Chol and 1/1/1 phosphatidylcholine/sphingomyelin/Chol lipid mixtures and managed to produce a GUV population of an average diameter around 40 µm, with many GUVs being larger than 100 µm. Additionally, compared to protocols that include the dry film step, the sizes and quality of vesicles determined from fluorescence microscopy images were similar or better, confirming the benefits of our protocol in that regard as well.
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Affiliation(s)
- Zvonimir Boban
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Faculty of Science, University of Split, Doctoral Study of Biophysics, 21000 Split, Croatia
| | - Ivan Mardešić
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Faculty of Science, University of Split, Doctoral Study of Biophysics, 21000 Split, Croatia
| | - Sanja Perinović Jozić
- Department of Organic Technology, Faculty of Chemistry and Technology, University of Split, 21000 Split, Croatia
| | - Josipa Šumanovac
- Department of Physics, Faculty of Science, University of Split, 21000 Split, Croatia
| | | | - Marija Raguz
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
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9
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Doğan Güzel F, Kaur J, Zendeh Z. Cheap portable electroformed giant unilamellar vesicles preparation kit. J Liposome Res 2022:1-6. [DOI: 10.1080/08982104.2022.2149777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Fatma Doğan Güzel
- Department of Biomedical Engineering, Faculty of Engineering and Natural Sciences, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Jaspreet Kaur
- Department of Electrical and Electronic Engineering, Faculty of Engineering and Natural Sciences, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Zahra Zendeh
- Department of Translational Medicine, Faculty of Medicine, Ankara Yıldırım Beyazıt University, Ankara, Turkey
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10
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Cheppali SK, Dharan R, Katzenelson R, Sorkin R. Supported Natural Membranes on Microspheres for Protein-Protein Interaction Studies. ACS APPLIED MATERIALS & INTERFACES 2022; 14:49532-49541. [PMID: 36306148 DOI: 10.1021/acsami.2c13095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Multiple biological and pathological processes, such as signaling, cell-cell communication, and infection by various viruses, occur at the plasma membrane. The eukaryotic plasma membrane is made up of thousands of different lipids, membrane proteins, and glycolipids, and its composition is dynamic and constantly changing. Due to the central importance of membranes on the one hand and their complexity on the other, membrane model systems are instrumental for interrogating membrane-related biological processes. Here, we develop a new tool for protein-membrane interaction studies. Our method is based on natural membranes obtained from extracellular vesicles. We form membrane bilayers supported on polystyrene microspheres that can be trapped and manipulated using optical tweezers. This method allows working with membrane proteins of interest within a background of native membrane components where their correct orientation is preserved. We demonstrate our method's applicability by successfully measuring the interaction forces between the Spike protein of SARS-CoV-2 and its human receptor, ACE2. We further show that these interactions are blocked by the addition of an antibody against the receptor binding domain of the Spike protein. Our approach is versatile and broadly applicable for various membrane biology and biophysics questions.
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Affiliation(s)
- Sudheer K Cheppali
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel6997801
| | - Raviv Dharan
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel6997801
| | - Roni Katzenelson
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel6997801
| | - Raya Sorkin
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel6997801
- Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel6997801
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11
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Pramanik S, Steinkühler J, Dimova R, Spatz J, Lipowsky R. Binding of His-tagged fluorophores to lipid bilayers of giant vesicles. SOFT MATTER 2022; 18:6372-6383. [PMID: 35975692 DOI: 10.1039/d2sm00915c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
His-tagged molecules can be attached to lipid bilayers via certain anchor lipids, a method that has been widely used for the biofunctionalization of membranes and vesicles. To observe the membrane-bound molecules, it is useful to consider His-tagged molecules that are fluorescent as well. Here, we study two such molecules, green fluorescence protein (GFP) and green-fluorescent fluorescein isothiocyanate (FITC), both of which are tagged with a chain of six histidines (6H) that bind to the anchor lipids within the bilayers. The His-tag 6H is much smaller than the GFP molecule but somewhat larger than the FITC dye. The lipid bilayers form giant unilamellar vesicles (GUVs), the behavior of which can be directly observed in the optical microscope. We apply and compare three well-established preparation methods for GUVs: electroformation on platinum wire, polyvinyl alcohol (PVA) hydrogel swelling, and electroformation on indium tin oxide (ITO) glass. Microfluidics is used to expose the GUVs to a constant fluorophore concentration in the exterior solution. The brightness of membrane-bound 6H-GFP exceeds the brightness of membrane-bound 6H-FITC, in contrast to the quantum yields of the two fluorophores in solution. In fact, 6H-FITC is observed to be strongly quenched by the anchor lipids which bind the fluorophores via Ni2+ ions. For both 6H-GFP and 6H-FITC, the membrane fluorescence is measured as a function of the fluorophores' molar concentration. The theoretical analysis of these data leads to the equilibrium dissociation constants Kd = 37.5 nM for 6H-GFP and Kd = 18.5 nM for 6H-FITC. We also observe a strong pH-dependence of the membrane fluorescence.
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Affiliation(s)
- Shreya Pramanik
- Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
| | - Jan Steinkühler
- Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
| | - Joachim Spatz
- Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
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12
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Faizi HA, Tsui A, Dimova R, Vlahovska PM. Bending Rigidity, Capacitance, and Shear Viscosity of Giant Vesicle Membranes Prepared by Spontaneous Swelling, Electroformation, Gel-Assisted, and Phase Transfer Methods: A Comparative Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10548-10557. [PMID: 35993569 PMCID: PMC9671160 DOI: 10.1021/acs.langmuir.2c01402] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Closed lipid bilayers in the form of giant unilamellar vesicles (GUVs) are commonly used membrane models. Various methods have been developed to prepare GUVs, however it is unknown if all approaches yield membranes with the same elastic, electric, and rheological properties. Here, we combine flickering spectroscopy and electrodefomation of GUVs to measure, at identical conditions, membrane capacitance, bending rigidity and shear surface viscosity of palmitoyloleoylphosphatidylcholine (POPC) membranes formed by several commonly used preparation methods: thin film hydration (spontaneous swelling), electroformation, gel-assisted swelling using poly(vinyl alcohol) (PVA) or agarose, and phase-transfer. We find relatively similar bending rigidity value across all the methods except for the agarose hydration method. In addition, the capacitance values are similar except for vesicles prepared via PVA gel hydration. Intriguingly, membranes prepared by the gel-assisted and phase-transfer methods exhibit much higher shear viscosity compared to electroformation and spontaneous swelling, likely due to remnants of polymers (PVA and agarose) and oils (hexadecane and mineral) in the lipid bilayer structure.
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Affiliation(s)
- Hammad A Faizi
- Department of Mechanical Engineering, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Annie Tsui
- Department of Industrial Engineering, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Petia M Vlahovska
- Department of Engineering Sciences and Applied Mathematics, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
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13
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Dolder N, Müller P, von Ballmoos C. Experimental platform for the functional investigation of membrane proteins in giant unilamellar vesicles. SOFT MATTER 2022; 18:5877-5893. [PMID: 35916307 PMCID: PMC9364335 DOI: 10.1039/d2sm00551d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Giant unilamellar vesicles (GUVs) are micrometer-sized model membrane systems that can be viewed directly under the microscope. They serve as scaffolds for the bottom-up creation of synthetic cells, targeted drug delivery and have been widely used to study membrane related phenomena in vitro. GUVs are also of interest for the functional investigation of membrane proteins that carry out many key cellular functions. A major hurdle to a wider application of GUVs in this field is the diversity of existing protocols that are optimized for individual proteins. Here, we compare PVA assisted and electroformation techniques for GUV formation under physiologically relevant conditions, and analyze the effect of immobilization on vesicle structure and membrane tightness towards small substrates and protons. There, differences in terms of yield, size, and leakage of GUVs produced by PVA assisted swelling and electroformation were found, dependent on salt and buffer composition. Using fusion of oppositely charged membranes to reconstitute a model membrane protein, we find that empty vesicles and proteoliposomes show similar fusion behavior, which allows for a rapid estimation of protein incorporation using fluorescent lipids.
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Affiliation(s)
- Nicolas Dolder
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
| | - Philipp Müller
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
| | - Christoph von Ballmoos
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
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14
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Podolsky KA, Masubuchi T, Debelouchina GT, Hui E, Devaraj NK. In Situ Assembly of Transmembrane Proteins from Expressed and Synthetic Components in Giant Unilamellar Vesicles. ACS Chem Biol 2022; 17:1015-1021. [PMID: 35482050 PMCID: PMC9255206 DOI: 10.1021/acschembio.2c00013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reconstituting functional transmembrane (TM) proteins into model membranes is challenging due to the difficulty of expressing hydrophobic TM domains, which often require stabilizing detergents that can perturb protein structure and function. Recent model systems solve this problem by linking the soluble domains of membrane proteins to lipids, using noncovalent conjugation. Herein, we test an alternative solution involving the in vitro assembly of TM proteins from synthetic TM domains and expressed soluble domains using chemoselective peptide ligation. We developed an intein mediated ligation strategy to semisynthesize single-pass TM proteins in synthetic giant unilamellar vesicle (GUV) membranes by covalently attaching soluble protein domains to a synthetic TM polypeptide, avoiding the requirement for detergent. We show that the extracellular domain of programmed cell death protein 1, a mammalian immune checkpoint receptor, retains its ligand-binding function at a membrane interface after ligation to a synthetic TM peptide in GUVs, facilitating the study of receptor-ligand interactions.
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Affiliation(s)
- K. A. Podolsky
- Department of Chemistry and Biochemistry, University of California, San Diego, CA, U.S.A
| | - T. Masubuchi
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, CA, U.S.A
| | - G. T. Debelouchina
- Department of Chemistry and Biochemistry, University of California, San Diego, CA, U.S.A
| | - E. Hui
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, CA, U.S.A
| | - N. K. Devaraj
- Department of Chemistry and Biochemistry, University of California, San Diego, CA, U.S.A.,Corresponding Author: Neal K. Devaraj,
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15
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Boban Z, Mardešić I, Subczynski WK, Raguz M. Giant Unilamellar Vesicle Electroformation: What to Use, What to Avoid, and How to Quantify the Results. MEMBRANES 2021; 11:membranes11110860. [PMID: 34832088 PMCID: PMC8622294 DOI: 10.3390/membranes11110860] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/03/2021] [Accepted: 11/05/2021] [Indexed: 12/12/2022]
Abstract
Since its inception more than thirty years ago, electroformation has become the most commonly used method for growing giant unilamellar vesicles (GUVs). Although the method seems quite straightforward at first, researchers must consider the interplay of a large number of parameters, different lipid compositions, and internal solutions in order to avoid artifactual results or reproducibility problems. These issues motivated us to write a short review of the most recent methodological developments and possible pitfalls. Additionally, since traditional manual analysis can lead to biased results, we have included a discussion on methods for automatic analysis of GUVs. Finally, we discuss possible improvements in the preparation of GUVs containing high cholesterol contents in order to avoid the formation of artifactual cholesterol crystals. We intend this review to be a reference for those trying to decide what parameters to use as well as an overview providing insight into problems not yet addressed or solved.
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Affiliation(s)
- Zvonimir Boban
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Doctoral Study of Biophysics, Faculty of Science, University of Split, 21000 Split, Croatia
| | - Ivan Mardešić
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Doctoral Study of Biophysics, Faculty of Science, University of Split, 21000 Split, Croatia
| | | | - Marija Raguz
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Correspondence: ; Tel.: +385-98-768-819
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16
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Zhang G, Sun J. Lipid in Chips: A Brief Review of Liposomes Formation by Microfluidics. Int J Nanomedicine 2021; 16:7391-7416. [PMID: 34764647 PMCID: PMC8575451 DOI: 10.2147/ijn.s331639] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Liposomes are ubiquitous tools in biomedical applications, such as drug delivery, membrane science and artificial cell. Micro- and nanofabrication techniques have revolutionized the preparation of liposomes on the microscale. State-of-the-art liposomal formation on microfluidic chips and its associated applications are introduced in this review. We attempt to provide a reference for liposomal researchers by comparing various microfluidic techniques for liposomes formation.
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Affiliation(s)
- Guo Zhang
- Department of Plastic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China
| | - Jiaming Sun
- Department of Plastic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China
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17
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Otrin L, Witkowska A, Marušič N, Zhao Z, Lira RB, Kyrilis FL, Hamdi F, Ivanov I, Lipowsky R, Kastritis PL, Dimova R, Sundmacher K, Jahn R, Vidaković-Koch T. En route to dynamic life processes by SNARE-mediated fusion of polymer and hybrid membranes. Nat Commun 2021; 12:4972. [PMID: 34404795 PMCID: PMC8371082 DOI: 10.1038/s41467-021-25294-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 07/30/2021] [Indexed: 12/11/2022] Open
Abstract
A variety of artificial cells springs from the functionalization of liposomes with proteins. However, these models suffer from low durability without repair and replenishment mechanisms, which can be partly addressed by replacing the lipids with polymers. Yet natural membranes are also dynamically remodeled in multiple cellular processes. Here, we show that synthetic amphiphile membranes also undergo fusion, mediated by the protein machinery for synaptic secretion. We integrated fusogenic SNAREs in polymer and hybrid vesicles and observed efficient membrane and content mixing. We determined bending rigidity and pore edge tension as key parameters for fusion and described its plausible progression through cryo-EM snapshots. These findings demonstrate that dynamic membrane phenomena can be reconstituted in synthetic materials, thereby providing new tools for the assembly of synthetic protocells.
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Affiliation(s)
- Lado Otrin
- Electrochemical Energy Conversion, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.
| | - Agata Witkowska
- Laboratory of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
- Department of Molecular Pharmacology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Nika Marušič
- Process Systems Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Ziliang Zhao
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Rafael B Lira
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Groningen, Netherlands
| | - Fotis L Kyrilis
- Interdisciplinary Research Center HALOmem & Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, Halle/Saale, Germany
| | - Farzad Hamdi
- Interdisciplinary Research Center HALOmem & Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, Halle/Saale, Germany
| | - Ivan Ivanov
- Process Systems Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Reinhard Lipowsky
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Panagiotis L Kastritis
- Interdisciplinary Research Center HALOmem & Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Biozentrum, Halle/Saale, Germany
| | - Rumiana Dimova
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Kai Sundmacher
- Process Systems Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Tanja Vidaković-Koch
- Electrochemical Energy Conversion, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
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18
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Endoplasmic reticulum phospholipid scramblase activity revealed after protein reconstitution into giant unilamellar vesicles containing a photostable lipid reporter. Sci Rep 2021; 11:14364. [PMID: 34257324 PMCID: PMC8277826 DOI: 10.1038/s41598-021-93664-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/28/2021] [Indexed: 02/04/2023] Open
Abstract
Transbilayer movement of phospholipids in biological membranes is mediated by a diverse set of lipid transporters. Among them are scramblases that facilitate a rapid bi-directional movement of lipids without metabolic energy input. Here, we established a new fluorescence microscopy-based assay for detecting phospholipid scramblase activity of membrane proteins upon their reconstitution into giant unilamellar vesicles formed from proteoliposomes by electroformation. The assay is based on chemical bleaching of fluorescence of a photostable ATTO-dye labeled phospholipid with the membrane-impermeant reductant sodium dithionite. We demonstrate that this new methodology is suitable for the study of the scramblase activity of the yeast endoplasmic reticulum at single vesicle level.
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19
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Tight docking of membranes before fusion represents a metastable state with unique properties. Nat Commun 2021; 12:3606. [PMID: 34127664 PMCID: PMC8203622 DOI: 10.1038/s41467-021-23722-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 05/11/2021] [Indexed: 12/26/2022] Open
Abstract
Membrane fusion is fundamental to biological processes as diverse as membrane trafficking or viral infection. Proteins catalyzing membrane fusion need to overcome energy barriers to induce intermediate steps in which the integrity of bilayers is lost. Here, we investigate the structural features of tightly docked intermediates preceding hemifusion. Using lipid vesicles in which progression to hemifusion is arrested, we show that the metastable intermediate does not require but is enhanced by divalent cations and is characterized by the absence of proteins and local membrane thickening. Molecular dynamics simulations reveal that thickening is due to profound lipid rearrangements induced by dehydration of the membrane surface. Proteins need to overcome energy barriers to induce intermediate steps in membrane fusion. Using lipid vesicles in which progression to hemifusion is arrested, the authors show that the metastable intermediate is enhanced by divalent cations and is characterized by the absence of proteins and local membrane thickening. Simulations reveal that thickening is induced by dehydration of the membrane surface.
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20
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Sych T, Gurdap CO, Wedemann L, Sezgin E. How Does Liquid-Liquid Phase Separation in Model Membranes Reflect Cell Membrane Heterogeneity? MEMBRANES 2021; 11:323. [PMID: 33925240 PMCID: PMC8146956 DOI: 10.3390/membranes11050323] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/22/2022]
Abstract
Although liquid-liquid phase separation of cytoplasmic or nuclear components in cells has been a major focus in cell biology, it is only recently that the principle of phase separation has been a long-standing concept and extensively studied in biomembranes. Membrane phase separation has been reconstituted in simplified model systems, and its detailed physicochemical principles, including essential phase diagrams, have been extensively explored. These model membrane systems have proven very useful to study the heterogeneity in cellular membranes, however, concerns have been raised about how reliably they can represent native membranes. In this review, we will discuss how phase-separated membrane systems can mimic cellular membranes and where they fail to reflect the native cell membrane heterogeneity. We also include a few humble suggestions on which phase-separated systems should be used for certain applications, and which interpretations should be avoided to prevent unreliable conclusions.
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Affiliation(s)
| | | | | | - Erdinc Sezgin
- Science for Life Laboratory, Department of Women’s and Children’s Health, Karolinska Institutet, 17165 Solna, Sweden; (T.S.); (C.O.G.); (L.W.)
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21
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Jennings CS, Rossman JS, Hourihan BA, Marshall RJ, Forgan RS, Blight BA. Immobilising giant unilamellar vesicles with zirconium metal-organic framework anchors. SOFT MATTER 2021; 17:2024-2027. [PMID: 33599656 DOI: 10.1039/d0sm02188a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Lipid bilayer vesicles have provided a window into the function and fundamental properties of cells. However, as is the case for most living and soft matter, vesicles do not remain still. This necessitates some microscopy experiments to include a preparatory immobilisation step. Here, we describe a straightforward method to immobilise giant unilamellar vesicles (GUVs) using zirconium-based metal-organic frameworks (MOFs) and demonstrate that GUVs bound in this way will stay in position on a timescale of minutes to hours.
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Affiliation(s)
- Christopher S Jennings
- Department of Chemistry, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - Jeremy S Rossman
- School of Biosciences, University of Kent, Canterbury, CT2 7NH, UK
| | - Braeden A Hourihan
- Department of Chemistry, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - Ross J Marshall
- WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK
| | - Ross S Forgan
- WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK
| | - Barry A Blight
- Department of Chemistry, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
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22
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Morini R, Bizzotto M, Perrucci F, Filipello F, Matteoli M. Strategies and Tools for Studying Microglial-Mediated Synapse Elimination and Refinement. Front Immunol 2021; 12:640937. [PMID: 33708226 PMCID: PMC7940197 DOI: 10.3389/fimmu.2021.640937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 02/01/2021] [Indexed: 01/14/2023] Open
Abstract
The role of microglia in controlling synapse homeostasis is becoming increasingly recognized by the scientific community. In particular, the microglia-mediated elimination of supernumerary synapses during development lays the basis for the correct formation of neuronal circuits in adulthood, while the possible reactivation of this process in pathological conditions, such as schizophrenia or Alzheimer's Disease, provides a promising target for future therapeutic strategies. The methodological approaches to investigate microglial synaptic engulfment include different in vitro and in vivo settings. Basic in vitro assays, employing isolated microglia and microbeads, apoptotic membranes, liposomes or synaptosomes allow the quantification of the microglia phagocytic abilities, while co-cultures of microglia and neurons, deriving from either WT or genetically modified mice models, provide a relatively manageable setting to investigate the involvement of specific molecular pathways. Further detailed analysis in mice brain is then mandatory to validate the in vitro assays as representative for the in vivo situation. The present review aims to dissect the main technical approaches to investigate microglia-mediated phagocytosis of neuronal and synaptic substrates in critical developmental time windows.
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Affiliation(s)
- Raffaella Morini
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy
| | - Matteo Bizzotto
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy.,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy
| | - Fabio Perrucci
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy.,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy
| | - Fabia Filipello
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy.,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy.,Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States
| | - Michela Matteoli
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy.,Consiglio Nazionale Delle Ricerche (CNR), Institute of Neuroscience - URT Humanitas, Rozzano, Italy
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23
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Wang X, Du H, Wang Z, Mu W, Han X. Versatile Phospholipid Assemblies for Functional Synthetic Cells and Artificial Tissues. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2002635. [PMID: 32830387 DOI: 10.1002/adma.202002635] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/09/2020] [Indexed: 06/11/2023]
Abstract
The bottom-up construction of a synthetic cell from nonliving building blocks capable of mimicking cellular properties and behaviors helps to understand the particular biophysical properties and working mechanisms of a cell. A synthetic cell built in this way possesses defined chemical composition and structure. Since phospholipids are native biomembrane components, their assemblies are widely used to mimic cellular structures. Here, recent developments in the formation of versatile phospholipid assemblies are described, together with the applications of these assemblies for functional membranes (protein reconstituted giant unilamellar vesicles), spherical and nonspherical protoorganelles, and functional synthetic cells, as well as the high-order hierarchical structures of artificial tissues. Their biomedical applications are also briefly summarized. Finally, the challenges and future directions in the field of synthetic cells and artificial tissues based on phospholipid assemblies are proposed.
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Affiliation(s)
- Xuejing Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Hang Du
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
- Marine Antifouling Engineering Technology Center of Shangdong Province, Harbin Institute of Technology, Weihai, 264209, China
| | - Zhao Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Wei Mu
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
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24
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Kataoka-Hamai C, Kawakami K. Domain Sorting in Giant Unilamellar Vesicles Adsorbed on Glass. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1082-1088. [PMID: 33440115 DOI: 10.1021/acs.langmuir.0c02843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Giant unilamellar vesicles (GUVs) adsorb to a solid surface and rupture to form a planar bilayer patch. These bilayer patches are used to investigate the properties and functions of biological membranes. Therefore, it is crucial to understand the mechanisms of GUV adsorption. In this study, we investigate the adsorption of phase-separated GUVs on glass using fluorescence microscopy. GUVs containing liquid-ordered (Lo) and liquid-disordered (Ld) phases underwent domain sorting after adsorption. The Ld domain in the unbound region migrated to the highly curved region near the edge of the adsorbed region. Additionally, the Lo phase grew linearly along the edge of the adsorbed region, creating a thin ring-like domain. After the domain sorting event, the GUV ruptured to form a planar bilayer patch with circular-patterned domains in the initially adsorbed area. We found that domain sorting was promoted by increasing the extent of GUV deformation. These results suggest that both the Ld and Lo domains are reorganized for stabilizing the curved bilayer region in adsorbed GUVs.
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Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
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25
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Staneva G, Watanabe C, Puff N, Yordanova V, Seigneuret M, Angelova MI. Amyloid-β Interactions with Lipid Rafts in Biomimetic Systems: A Review of Laboratory Methods. Methods Mol Biol 2021; 2187:47-86. [PMID: 32770501 DOI: 10.1007/978-1-0716-0814-2_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biomimetic lipid bilayer systems are a useful tool for modeling specific properties of cellular membranes in order to answer key questions about their structure and functions. This approach has prompted scientists from all over the world to create more and more sophisticated model systems in order to decipher the complex lateral and transverse organization of cellular plasma membranes. Among a variety of existing biomembrane domains, lipid rafts are defined as small, dynamic, and ordered assemblies of lipids and proteins, enriched in cholesterol and sphingolipids. Lipid rafts appear to be involved in the development of Alzheimer's disease (AD) by affecting the aggregation of the amyloid-β (Aβ) peptide at neuronal membranes thereby forming toxic oligomeric species. In this review, we summarize the laboratory methods which allow to study the interaction of Aβ with lipid rafts. We describe step by step protocols to form giant (GUVs) and large unilamellar vesicles (LUVs) containing raft-mimicking domains surrounded by membrane nonraft regions. Using fluorescence microscopy GUV imaging protocols, one can design experiments to visualize micron-scale raft-like domains, to determine the micron-scale demixing temperature of a given lipid mixture, construct phase diagram, and photogenerate domains in order to assess the dynamics of raft formation and raft size distribution. LUV fluorescence spectroscopy protocols with proper data analysis can be used to measure molecular packing of raft/nonraft regions of the membrane, to report on nanoscale raft formation and determine nanoscale demixing temperature. Because handling of the Aβ requires dedicated laboratory experience, we present illustrated protocols for Aβ-stock aliquoting, Aβ aqueous solubilization, oligomer preparation, determination of the Aβ concentration before and after filtration. Thioflavin binding, dynamic light scattering, and transmission electron microscopy protocols are described as complementary methods to detect Aβ aggregation kinetics, aggregate sizes, and morphologies of observed aggregates.
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Affiliation(s)
- Galya Staneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Chiho Watanabe
- Komaba Institute for Science, The University of Tokyo, Tokyo, Japan
| | - Nicolas Puff
- Faculty of Science and Engineering, UFR 925 Physics, Sorbonne Université, Paris, France
- Laboratoire Matière et Systèmes Complexes (MSC) UMR 7057 CNRS, Université Paris Diderot - Paris 7, Université de Paris, Paris, France
| | - Vesela Yordanova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Michel Seigneuret
- Laboratoire Matière et Systèmes Complexes (MSC) UMR 7057 CNRS, Université Paris Diderot - Paris 7, Université de Paris, Paris, France
| | - Miglena I Angelova
- Faculty of Science and Engineering, UFR 925 Physics, Sorbonne Université, Paris, France
- Laboratoire Matière et Systèmes Complexes (MSC) UMR 7057 CNRS, Université Paris Diderot - Paris 7, Université de Paris, Paris, France
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26
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Rahman MM, Williams SJ. Membrane tension may define the deadliest virus infection. COLLOID AND INTERFACE SCIENCE COMMUNICATIONS 2021; 40:100338. [PMID: 34722169 PMCID: PMC8544801 DOI: 10.1016/j.colcom.2020.100338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/06/2020] [Accepted: 11/08/2020] [Indexed: 05/23/2023]
Abstract
This manuscript describes the potentially significant role of interfacial tension in viral infection. Our hypothesis is based on evidence from drop coalescence hydrodynamics. A change in membrane tension can trigger fusion between the vesicle and cell such that genetic material, like viral RNA, can subsequently be transported to the cell interior. In other cases, RNA may reside near the cell membrane inside the cell, which could make their removal energetically unfavorable because of hydrodynamic interactions between membrane and RNA. Interfacial tension of the virus membrane can be modulated by temperature, among many other factors, of the mucosa layer. We discuss our hypothesis within the scope of recent SARS-CoV-2 studies where temperature-dependent membrane surface tension could be impacted through different atmospheric conditions, air conditioning systems, and the use of masks.
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Affiliation(s)
| | - Stuart J Williams
- Department of Mechanical Engineering, University of Louisville, KY, USA
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27
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Musteikytė G, Jayaram AK, Xu CK, Vendruscolo M, Krainer G, Knowles TPJ. Interactions of α-synuclein oligomers with lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183536. [PMID: 33373595 DOI: 10.1016/j.bbamem.2020.183536] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/10/2020] [Accepted: 12/13/2020] [Indexed: 12/24/2022]
Abstract
Parkinson's disease is an increasingly prevalent and currently incurable neurodegenerative disorder. At the molecular level, this disease is characterized by the formation of aberrant intracellular protein deposits known as Lewy bodies. Oligomeric forms of the protein α-synuclein (αS), which are believed to be both intermediates and by-products of Lewy body formation, are considered to be the main pathogenic species. Interactions of such oligomers with lipid membranes are increasingly emerging as a major molecular pathway underpinning their toxicity. Here we review recent progress in our understanding of the interactions of αS oligomers with lipid membranes. We highlight key structural and biophysical features of αS oligomers, the effects of these features on αS oligomer membrane binding properties, and resultant implications for understanding the etiology of Parkinson's disease. We discuss mechanistic modes of αS oligomer-lipid membrane interactions and the effects of environmental factors to such modes. Finally, we provide an overview of the current understanding of the main molecular determinants of αS oligomer toxicity in vivo.
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Affiliation(s)
- Greta Musteikytė
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Akhila K Jayaram
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom; Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Catherine K Xu
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Georg Krainer
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
| | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom; Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
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28
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Witkowska A, Spindler S, Mahmoodabadi RG, Sandoghdar V, Jahn R. Differential Diffusional Properties in Loose and Tight Docking Prior to Membrane Fusion. Biophys J 2020; 119:2431-2439. [PMID: 33189687 PMCID: PMC7822739 DOI: 10.1016/j.bpj.2020.10.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/20/2020] [Accepted: 10/27/2020] [Indexed: 12/21/2022] Open
Abstract
Fusion of biological membranes, although mediated by divergent proteins, is believed to follow a common pathway. It proceeds through distinct steps, including docking, merger of proximal leaflets (stalk formation), and formation of a fusion pore. However, the structure of these intermediates is difficult to study because of their short lifetime. Previously, we observed a loosely and tightly docked state preceding leaflet merger using arresting point mutations in SNARE proteins, but the nature of these states remained elusive. Here, we used interferometric scattering (iSCAT) microscopy to monitor diffusion of single vesicles across the surface of giant unilamellar vesicles (GUVs). We observed that the diffusion coefficients of arrested vesicles decreased during progression through the intermediate states. Modeling allowed for predicting the number of tethering SNARE complexes upon loose docking and the size of the interacting membrane patches upon tight docking. These results shed new light on the nature of membrane-membrane interactions immediately before fusion.
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Affiliation(s)
- Agata Witkowska
- Laboratory of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
| | - Susann Spindler
- Max Planck Institute for the Science of Light, Erlangen, Germany; Department of Physics, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Reza Gholami Mahmoodabadi
- Max Planck Institute for the Science of Light, Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Vahid Sandoghdar
- Max Planck Institute for the Science of Light, Erlangen, Germany; Department of Physics, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany.
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany; University of Göttingen, Göttingen, Germany.
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Armstrong M, Vahey MD, Hunt TP, Fletcher DA. Forming and loading giant unilamellar vesicles with acoustic jetting. BIOMICROFLUIDICS 2020; 14:064105. [PMID: 33269034 PMCID: PMC7679179 DOI: 10.1063/5.0021742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/15/2020] [Indexed: 05/04/2023]
Abstract
Giant unilamellar vesicles (GUVs) are a useful platform for reconstituting and studying membrane-bound biological systems, offering reduced complexity compared to living cells. Several techniques exist to form GUVs and populate them with biomolecules of interest. However, a persistent challenge is the ability to efficiently and reliably load solutions of biological macromolecules, organelle-like membranes, and/or micrometer-scale particles with controlled stoichiometry in the encapsulated volume of GUVs. Here, we demonstrate the use of acoustic streaming from high-intensity focused ultrasound to make and load GUVs from bulk solutions, without the need for nozzles that can become clogged or otherwise alter the solution composition. In this method, a compact acoustic lens is focused on a planar lipid bilayer formed between two aqueous solutions. The actuation of a planar piezoelectric material coupled to the lens accelerates a small volume of liquid, deforming the bilayer and forming a GUV containing the solution on the transducer side of the bilayer. As demonstrated here, acoustic jetting offers an alternative method for the generation of GUVs for biological and biophysical studies.
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Affiliation(s)
- Maxim Armstrong
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, USA
| | - Michael D. Vahey
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, USA
| | - Thomas P. Hunt
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, USA
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Behuria HG, Biswal BK, Sahu SK. Electroformation of liposomes and phytosomes using copper electrode. J Liposome Res 2020; 31:255-266. [PMID: 32703044 DOI: 10.1080/08982104.2020.1800729] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A novel method for electroformation of liposomes and phytosomes using copper electrode is described. Liposomes made at 2 V and 10 Hz AC field from L-α-egg-phosphatidylcholine (egg-PC), K. pneumoniae phosphatidylethanolamine, K. pneumoniae polar lipids and E. coli polar lipids on copper electrode were (777.9 ± 118.4), (370.2 ± 100.5), (825.3 ± 21.54), and (281.3 ± 42.3) nm in diameter, respectively. Giant vesicles were formed at 30 V and 10 Hz AC field from polar lipids of K. pneumoniae and E. coli were (106 ± 29.7) and (86 ± 24.3) µm in diameter, respectively. All liposomes were unilamellar as indicated by their unilamellar indices of 50 ± 2, had surface charge comparable to vesicles made from lipid(s) with similar composition and exhibited only 1-2 mol% of oxidized lipids. Cu concentration in the liposomal samples was <1.5 ppm for large unilamellar vesicles (LUVs) and ˂5 ppm for giant unilamellar vesicles (GUVs). The vesicles were stable for >15 d without loss of their size, charge, or unilamellarity. The method was successfully applied to prepare phytosomes from egg-PC and a phytochemical fraction of Dimorphocalyx glabellus, a medicinal plant with anti-diuretic properties. Phytosomes formed were 1000-1500 nm in diameter and exhibited altered fluorescence and absorbance properties compared to the unencapsulated phytochemical. Phytosomes with phytochemical: egg-PC ratio from 0.15 to 1.5 had encapsulation efficiency ranging 90-30%, respectively, and was stable for 1 month. Our method is easy, inexpensive and convenient that will prove to be useful for preparation of liposomes and phytosomes.
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Affiliation(s)
- Himadri Gourav Behuria
- Department of Biotechnology, Laboratory of Molecular Membrane Biology, North Orissa University, Baripada, India
| | - Bijesh Kumar Biswal
- Department of Life Science, National Institute of Technology, Rourkela, India
| | - Santosh Kumar Sahu
- Department of Biotechnology, Laboratory of Molecular Membrane Biology, North Orissa University, Baripada, India
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31
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Céspedes PF, Beckers D, Dustin ML, Sezgin E. Model membrane systems to reconstitute immune cell signaling. FEBS J 2020; 288:1070-1090. [DOI: 10.1111/febs.15488] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/26/2020] [Accepted: 07/14/2020] [Indexed: 12/26/2022]
Affiliation(s)
- Pablo F. Céspedes
- Kennedy Institute of Rheumatology Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences University of Oxford UK
| | - Daniel Beckers
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular Medicine University of Oxford UK
| | - Michael L. Dustin
- Kennedy Institute of Rheumatology Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences University of Oxford UK
| | - Erdinc Sezgin
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular Medicine University of Oxford UK
- Science for Life Laboratory Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden
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32
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Hindley JW, Law RV, Ces O. Membrane functionalization in artificial cell engineering. SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-2357-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AbstractBottom-up synthetic biology aims to construct mimics of cellular structure and behaviour known as artificial cells from a small number of molecular components. The development of this nascent field has coupled new insights in molecular biology with large translational potential for application in fields such as drug delivery and biosensing. Multiple approaches have been applied to create cell mimics, with many efforts focusing on phospholipid-based systems. This mini-review focuses on different approaches to incorporating molecular motifs as tools for lipid membrane functionalization in artificial cell construction. Such motifs range from synthetic chemical functional groups to components from extant biology that can be arranged in a ‘plug-and-play’ approach which is hard to replicate in living systems. Rationally designed artificial cells possess the promise of complex biomimetic behaviour from minimal, highly engineered chemical networks.
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Grimmer M, Bacia K. Giant Endoplasmic Reticulum vesicles (GERVs), a novel model membrane tool. Sci Rep 2020; 10:3100. [PMID: 32080222 PMCID: PMC7033103 DOI: 10.1038/s41598-020-59700-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
Artificial giant vesicles have proven highly useful as membrane models in a large variety of biophysical and biochemical studies. They feature accessibility for manipulation and detection, but lack the compositional complexity needed to reconstitute complicated cellular processes. For the plasma membrane (PM), this gap was bridged by the establishment of giant PM vesicles (GPMVs). These native membranes have facilitated studies of protein and lipid diffusion, protein interactions, electrophysiology, fluorescence analysis of lateral domain formation and protein and lipid partitioning as well as mechanical membrane properties and remodeling. The endoplasmic reticulum (ER) is key to a plethora of biological processes in any eukaryotic cell. However, its intracellular location and dynamic and intricate tubular morphology makes it experimentally even less accessible than the PM. A model membrane, which will allow the afore-mentioned types of studies on GPMVs to be performed on ER membranes outside the cell, is therefore genuinely needed. Here, we introduce the formation of giant ER vesicles, termed GERVs, as a new tool for biochemistry and biophysics. To obtain GERVs, we have isolated ER membranes from Saccharomyces cerevisiae and fused them by exploiting the atlastin-like fusion protein Sey1p. We demonstrate the production of GERVs and their utility for further studies.
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Affiliation(s)
- Mona Grimmer
- Biophysical Chemistry, Institute of Chemistry, Charles-Tanford Protein Center, University of Halle, Kurt-Mothes-Str. 3 A, 06120, Halle, Germany
| | - Kirsten Bacia
- Biophysical Chemistry, Institute of Chemistry, Charles-Tanford Protein Center, University of Halle, Kurt-Mothes-Str. 3 A, 06120, Halle, Germany.
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34
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Has C, Sunthar P. A comprehensive review on recent preparation techniques of liposomes. J Liposome Res 2019; 30:336-365. [DOI: 10.1080/08982104.2019.1668010] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- C. Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - P. Sunthar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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35
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Stuhr-Hansen N, Vagianou CD, Blixt O. Clustering of Giant Unilamellar Vesicles Promoted by Covalent and Noncovalent Bonding of Functional Groups at Membrane-Embedded Peptides. Bioconjug Chem 2019; 30:2156-2164. [DOI: 10.1021/acs.bioconjchem.9b00394] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Nicolai Stuhr-Hansen
- Department of Chemistry, Chemical Biology, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Charikleia-Despoina Vagianou
- Department of Chemistry, Chemical Biology, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Ola Blixt
- Department of Chemistry, Chemical Biology, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
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36
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dos Santos JL, Mendanha SA, Vieira SL, Gonçalves C. Portable Proportional-Integral-Derivative controlled chambers for giant unilamellar vesicles electroformation. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/ab1a1b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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37
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Supramaniam P, Ces O, Salehi-Reyhani A. Microfluidics for Artificial Life: Techniques for Bottom-Up Synthetic Biology. MICROMACHINES 2019; 10:E299. [PMID: 31052344 PMCID: PMC6562628 DOI: 10.3390/mi10050299] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/24/2019] [Accepted: 04/26/2019] [Indexed: 01/08/2023]
Abstract
Synthetic biology is a rapidly growing multidisciplinary branch of science that exploits the advancement of molecular and cellular biology. Conventional modification of pre-existing cells is referred to as the top-down approach. Bottom-up synthetic biology is an emerging complementary branch that seeks to construct artificial cells from natural or synthetic components. One of the aims in bottom-up synthetic biology is to construct or mimic the complex pathways present in living cells. The recent, and rapidly growing, application of microfluidics in the field is driven by the central tenet of the bottom-up approach-the pursuit of controllably generating artificial cells with precisely defined parameters, in terms of molecular and geometrical composition. In this review we survey conventional methods of artificial cell synthesis and their limitations. We proceed to show how microfluidic approaches have been pivotal in overcoming these limitations and ushering in a new generation of complexity that may be imbued in artificial cells and the milieu of applications that result.
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Affiliation(s)
- Pashiini Supramaniam
- Department of Chemistry, White City Campus, Imperial College London, London SW7 2AZ, UK.
| | - Oscar Ces
- Department of Chemistry, White City Campus, Imperial College London, London SW7 2AZ, UK.
- FabriCELL, Imperial College London, London SW7 2AZ, UK.
| | - Ali Salehi-Reyhani
- FabriCELL, Imperial College London, London SW7 2AZ, UK.
- Department of Chemistry, King's College London, Britannia House, London SE1 1DB, UK.
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38
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Rideau E, Wurm FR, Landfester K. Self‐Assembly of Giant Unilamellar Vesicles by Film Hydration Methodologies. ACTA ACUST UNITED AC 2019; 3:e1800324. [DOI: 10.1002/adbi.201800324] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/01/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Emeline Rideau
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Frederik R. Wurm
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
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