1
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Waeterschoot J, Gosselé W, Lemež Š, Casadevall I Solvas X. Artificial cells for in vivo biomedical applications through red blood cell biomimicry. Nat Commun 2024; 15:2504. [PMID: 38509073 PMCID: PMC10954685 DOI: 10.1038/s41467-024-46732-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/08/2024] [Indexed: 03/22/2024] Open
Abstract
Recent research in artificial cell production holds promise for the development of delivery agents with therapeutic effects akin to real cells. To succeed in these applications, these systems need to survive the circulatory conditions. In this review we present strategies that, inspired by the endurance of red blood cells, have enhanced the viability of large, cell-like vehicles for in vivo therapeutic use, particularly focusing on giant unilamellar vesicles. Insights from red blood cells can guide modifications that could transform these platforms into advanced drug delivery vehicles, showcasing biomimicry's potential in shaping the future of therapeutic applications.
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Affiliation(s)
- Jorik Waeterschoot
- Department of Biosystems - MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Leuven, Belgium.
| | - Willemien Gosselé
- Department of Biosystems - MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Leuven, Belgium
| | - Špela Lemež
- Department of Biosystems - MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Leuven, Belgium
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2
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Shendrik P, Golani G, Dharan R, Schwarz US, Sorkin R. Membrane Tension Inhibits Lipid Mixing by Increasing the Hemifusion Stalk Energy. ACS NANO 2023; 17:18942-18951. [PMID: 37669531 PMCID: PMC7615193 DOI: 10.1021/acsnano.3c04293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Accepted: 08/23/2023] [Indexed: 09/07/2023]
Abstract
Fusion of biological membranes is fundamental in various physiological events. The fusion process involves several intermediate stages with energy barriers that are tightly dependent on the mechanical and physical properties of the system, one of which is membrane tension. As previously established, the late stages of fusion, including hemifusion diaphragm and pore expansions, are favored by membrane tension. However, a current understanding of how the energy barrier of earlier fusion stages is affected by membrane tension is lacking. Here, we apply a newly developed experimental approach combining micropipette-aspirated giant unilamellar vesicles and optically trapped membrane-coated beads, revealing that membrane tension inhibits lipid mixing. We show that lipid mixing is 6 times slower under a tension of 0.12 mN/m compared with tension-free membranes. Furthermore, using continuum elastic theory, we calculate the dependence of the hemifusion stalk formation energy on membrane tension and intermembrane distance and find the increase in the corresponding energy barrier to be 1.6 kBT in our setting, which can explain the increase in lipid mixing time delay. Finally, we show that tension can be a significant factor in the stalk energy if the pre-fusion intermembrane distance is on the order of several nanometers, while for membranes that are tightly docked, tension has a negligible effect.
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Affiliation(s)
- Petr Shendrik
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Gonen Golani
- Institute
for Theoretical Physics and BioQuant Center for Quantitative Biology, Heidelberg University, 69120, Heidelberg, Germany
| | - Raviv Dharan
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ulrich S. Schwarz
- Institute
for Theoretical Physics and BioQuant Center for Quantitative Biology, Heidelberg University, 69120, Heidelberg, Germany
| | - Raya Sorkin
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
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3
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Tapie P, Prevost AM, Montel L, Pontani LL, Wandersman E. A simple method to make, trap and deform a vesicle in a gel. Sci Rep 2023; 13:5375. [PMID: 37009808 PMCID: PMC10068607 DOI: 10.1038/s41598-023-31996-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 03/21/2023] [Indexed: 04/04/2023] Open
Abstract
We present a simple method to produce giant lipid pseudo-vesicles (vesicles with an oily cap on the top), trapped in an agarose gel. The method can be implemented using only a regular micropipette and relies on the formation of a water/oil/water double droplet in liquid agarose. We characterize the produced vesicle with fluorescence imaging and establish the presence and integrity of the lipid bilayer by the successful insertion of [Formula: see text]-Hemolysin transmembrane proteins. Finally, we show that the vesicle can be easily mechanically deformed, non-intrusively, by indenting the surface of the gel.
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Affiliation(s)
- Pierre Tapie
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 4 place Jussieu, 75005, Paris, France
| | - Alexis M Prevost
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 4 place Jussieu, 75005, Paris, France
| | - Lorraine Montel
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 4 place Jussieu, 75005, Paris, France
| | - Léa-Laetitia Pontani
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 4 place Jussieu, 75005, Paris, France.
| | - Elie Wandersman
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 4 place Jussieu, 75005, Paris, France.
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4
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Studying membrane fusion using supported lipid bilayers on superparamagnetic beads. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184070. [PMID: 36220376 DOI: 10.1016/j.bbamem.2022.184070] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/29/2022] [Accepted: 10/03/2022] [Indexed: 11/13/2022]
Abstract
The fusion between two lipid membranes is a ubiquitous mechanism in cell traffic and pathogens invasion. Yet it is not well understood how two distinct bilayers overcome the energy barriers towards fusion and reorganize themselves to form a unique continuous bilayer. The magnitudes and numbers of these energy barriers are themselves an open question. To tackle these issues, we developed a new tool that allows to control the forces applied between two supported lipid bilayers (SLBs) deposited on superparamagnetic beads. By applying a magnetic field, the beads self-organize along field lines in chains of beads and compress the two membranes on the contact zone. Using the diffusion of fluorescently labelled lipids from one bilayer to the other allows us to identify fusion of the bilayers in contact. We applied increasing forces on SLBs and increased the occurrence of fusion. This experimental system allows the simultaneous study of tens of facing bilayers in a single experiment and mitigates the stochasticity of the fusion process. It is thus a powerful tool to test the various parameters involved in the membrane fusion process.
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5
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Staufer O, Gantner G, Platzman I, Tanner K, Berger I, Spatz JP. Bottom-up assembly of viral replication cycles. Nat Commun 2022; 13:6530. [PMID: 36323671 PMCID: PMC9628313 DOI: 10.1038/s41467-022-33661-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 09/27/2022] [Indexed: 11/05/2022] Open
Abstract
Bottom-up synthetic biology provides new means to understand living matter by constructing minimal life-like systems. This principle can also be applied to study infectious diseases. Here we summarize approaches and ethical considerations for the bottom-up assembly of viral replication cycles.
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Affiliation(s)
- Oskar Staufer
- Max Planck-Bristol Center for Minimal Biology, University of Bristol, 1 Tankard's Close, Bristol, BS8 1TD, UK.
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, OX3 7FY, UK.
- Max Planck School Matter to Life, Jahnstraße 29, 69120, Heidelberg, Germany.
| | - Gösta Gantner
- Max Planck School Matter to Life, Jahnstraße 29, 69120, Heidelberg, Germany
- Theological Seminary, Heidelberg University, Kisselgasse 1, 69117, Heidelberg, Germany
| | - Ilia Platzman
- Max Planck-Bristol Center for Minimal Biology, University of Bristol, 1 Tankard's Close, Bristol, BS8 1TD, UK
- Department for Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120, Heidelberg, Germany
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), University of Heidelberg, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Klaus Tanner
- Max Planck School Matter to Life, Jahnstraße 29, 69120, Heidelberg, Germany
- Theological Seminary, Heidelberg University, Kisselgasse 1, 69117, Heidelberg, Germany
| | - Imre Berger
- Max Planck-Bristol Center for Minimal Biology, University of Bristol, 1 Tankard's Close, Bristol, BS8 1TD, UK
- School of Biochemistry, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Bristol, BS8 1TD, UK
- Bristol Synthetic Biology Centre BrisSynBio, University of Bristol, 4 Tyndall Ave, Bristol, BS8 1TQ, UK
| | - Joachim P Spatz
- Max Planck-Bristol Center for Minimal Biology, University of Bristol, 1 Tankard's Close, Bristol, BS8 1TD, UK
- Max Planck School Matter to Life, Jahnstraße 29, 69120, Heidelberg, Germany
- Department for Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120, Heidelberg, Germany
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), University of Heidelberg, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
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6
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Imai M, Sakuma Y, Kurisu M, Walde P. From vesicles toward protocells and minimal cells. SOFT MATTER 2022; 18:4823-4849. [PMID: 35722879 DOI: 10.1039/d1sm01695d] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In contrast to ordinary condensed matter systems, "living systems" are unique. They are based on molecular compartments that reproduce themselves through (i) an uptake of ingredients and energy from the environment, and (ii) spatially and timely coordinated internal chemical transformations. These occur on the basis of instructions encoded in information molecules (DNAs). Life originated on Earth about 4 billion years ago as self-organised systems of inorganic compounds and organic molecules including macromolecules (e.g. nucleic acids and proteins) and low molar mass amphiphiles (lipids). Before the first living systems emerged from non-living forms of matter, functional molecules and dynamic molecular assemblies must have been formed as prebiotic soft matter systems. These hypothetical cell-like compartment systems often are called "protocells". Other systems that are considered as bridging units between non-living and living systems are called "minimal cells". They are synthetic, autonomous and sustainable reproducing compartment systems, but their constituents are not limited to prebiotic substances. In this review, we focus on both membrane-bounded (vesicular) protocells and minimal cells, and provide a membrane physics background which helps to understand how morphological transformations of vesicle systems might have happened and how vesicle reproduction might be coupled with metabolic reactions and information molecules. This research, which bridges matter and life, is a great challenge in which soft matter physics, systems chemistry, and synthetic biology must take joined efforts to better understand how the transformation of protocells into living systems might have occurred at the origin of life.
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Affiliation(s)
- Masayuki Imai
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Yuka Sakuma
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Minoru Kurisu
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Peter Walde
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, CH-8093 Zürich, Switzerland
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7
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Nomura SM, Shimizu R, Archer RJ, Hayase G, Toyota T, Mayne R, Adamatzky A. Spontaneous and Driven Growth of Multicellular Lipid Compartments to Millimeter Size from Porous Polymer Structures**. CHEMSYSTEMSCHEM 2022. [DOI: 10.1002/syst.202200006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shin‐ichiro M. Nomura
- Molecular Robotics Laboratory, Department of Robotics Graduate School of Engineering Tohoku University Sendai 980-8579 Japan
- Unconventional Computing Laboratory University of the West of England Bristol BS16 1QY United Kingdom
| | - Ryo Shimizu
- Molecular Robotics Laboratory, Department of Robotics Graduate School of Engineering Tohoku University Sendai 980-8579 Japan
| | - Richard James Archer
- Molecular Robotics Laboratory, Department of Robotics Graduate School of Engineering Tohoku University Sendai 980-8579 Japan
| | - Gen Hayase
- International Center for Materials Nanoarchitectonics National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki, 305-0044 Japan
| | - Taro Toyota
- Department of Basic Science, Graduate School of Arts and Sciences The University of Tokyo Komaba, 3-8-1 Komaba Meguro Tokyo 153-8902 Japan)
| | - Richard Mayne
- Unconventional Computing Laboratory University of the West of England Bristol BS16 1QY United Kingdom
| | - Andrew Adamatzky
- Unconventional Computing Laboratory University of the West of England Bristol BS16 1QY United Kingdom
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8
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Tolosa-Díaz A, Almendro-Vedia VG, Natale P, López-Montero I. The GDP-Bound State of Mitochondrial Mfn1 Induces Membrane Adhesion of Apposing Lipid Vesicles through a Cooperative Binding Mechanism. Biomolecules 2020; 10:biom10071085. [PMID: 32708307 PMCID: PMC7407159 DOI: 10.3390/biom10071085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 01/01/2023] Open
Abstract
Mitochondria are double-membrane organelles that continuously undergo fission and fusion. Outer mitochondrial membrane fusion is mediated by the membrane proteins mitofusin 1 (Mfn1) and mitofusin 2 (Mfn2), carrying a GTP hydrolyzing domain (GTPase) and two coiled-coil repeats. The detailed mechanism on how the GTP hydrolysis allows Mfns to approach adjacent membranes into proximity and promote their fusion is currently under debate. Using model membranes built up as giant unilamellar vesicles (GUVs), we show here that Mfn1 promotes membrane adhesion of apposing lipid vesicles. The adhesion forces were sustained by the GDP-bound state of Mfn1 after GTP hydrolysis. In contrast, the incubation with the GDP:AlF4−, which mimics the GTP transition state, did not induce membrane adhesion. Due to the flexible nature of lipid membranes, the adhesion strength depended on the surface concentration of Mfn1 through a cooperative binding mechanism. We discuss a possible scenario for the outer mitochondrial membrane fusion based on the modulated action of Mfn1.
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Affiliation(s)
- Andrés Tolosa-Díaz
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Víctor G. Almendro-Vedia
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Paolo Natale
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
| | - Iván López-Montero
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
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9
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Omidvar R, Römer W. Glycan-decorated protocells: novel features for rebuilding cellular processes. Interface Focus 2019; 9:20180084. [PMID: 30842879 DOI: 10.1098/rsfs.2018.0084] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2019] [Indexed: 02/06/2023] Open
Abstract
In synthetic biology approaches, lipid vesicles are widely used as protocell models. While many compounds have been encapsulated in vesicles (e.g. DNA, cytoskeleton and enzymes), the incorporation of glycocalyx components in the lipid bilayer has attracted much less attention so far. In recent years, glycoconjugates have been integrated in the membrane of giant unilamellar vesicles (GUVs). These minimal membrane systems have largely contributed to shed light on the molecular mechanisms of cellular processes. In this review, we first introduce several preparation and biophysical characterization methods of GUVs. Then, we highlight specific applications of protocells investigating glycolipid-mediated endocytosis of toxins, viruses and bacteria. In addition, we delineate how prototissues have been assembled from glycan-decorated protocells by using lectin-mediated cross-linking of opposed glycoreceptors (e.g. glycolipids and glycopeptides). In future applications, glycan-decorated protocells might be useful for investigating cell-cell interactions (e.g. adhesion and communication). We also speculate about the implication of lectin-glycoreceptor interactions in membrane fusion processes.
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Affiliation(s)
- Ramin Omidvar
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, Schänzlestraße 18, 79104 Freiburg, Germany.,Freiburg Center for Interactive Materials and Bioinspired Technology (FIT), Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Winfried Römer
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, Schänzlestraße 18, 79104 Freiburg, Germany.,Freiburg Center for Interactive Materials and Bioinspired Technology (FIT), Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
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10
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Ivanov I, Lira RB, Tang TYD, Franzmann T, Klosin A, da Silva LC, Hyman A, Landfester K, Lipowsky R, Sundmacher K, Dimova R. Directed Growth of Biomimetic Microcompartments. ACTA ACUST UNITED AC 2019; 3:e1800314. [PMID: 32648704 DOI: 10.1002/adbi.201800314] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/15/2019] [Indexed: 01/04/2023]
Abstract
Contemporary biological cells are sophisticated and highly compartmentalized. Compartmentalization is an essential principle of prebiotic life as well as a key feature in bottom-up synthetic biology research. In this review, the dynamic growth of compartments as an essential prerequisite for enabling self-reproduction as a fundamental life process is discussed. The micrometer-sized compartments are focused on due to their cellular dimensions. Two types of compartments are considered, membraneless droplets and membrane-bound microcompartments. Growth mechanisms of aqueous droplets such as protein (condensates) or macromolecule-rich droplets (aqueous two phase systems) and coacervates are discussed, for which growth occurs via Ostwald ripening or coalescence. For membrane-bound compartments, vesicles are considered, which are composed of fatty acids, lipids, or polymers, where directed growth can occur via fusion or uptake of material from the surrounding. The development of novel approaches for growth of biomimetic microcompartments can eventually be utilized to construct new synthetic cells.
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Affiliation(s)
- Ivan Ivanov
- Max Planck Institute for Dynamics of Complex Technical Systems, Process Systems Engineering, Sandtorstrasse 1, 39106, Magdeburg, Germany
| | - Rafael B Lira
- Max Planck Institute of Colloids and Interfaces, Theory and Bio-Systems, Science Park Golm, 14424, Potsdam, Germany
| | - T-Y Dora Tang
- Max Planck Institute of Molecular Cell Biology and Genetics, Organization of Cytoplasm & Dynamic Protocellular Systems, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Titus Franzmann
- Max Planck Institute of Molecular Cell Biology and Genetics, Organization of Cytoplasm & Dynamic Protocellular Systems, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Adam Klosin
- Max Planck Institute of Molecular Cell Biology and Genetics, Organization of Cytoplasm & Dynamic Protocellular Systems, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Lucas Caire da Silva
- Max Planck Institute for Polymer Research, Physical Chemistry of Polymers, Ackermannweg 10, 55128, Mainz, Germany
| | - Anthony Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Organization of Cytoplasm & Dynamic Protocellular Systems, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Katharina Landfester
- Max Planck Institute for Polymer Research, Physical Chemistry of Polymers, Ackermannweg 10, 55128, Mainz, Germany
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Theory and Bio-Systems, Science Park Golm, 14424, Potsdam, Germany
| | - Kai Sundmacher
- Max Planck Institute for Dynamics of Complex Technical Systems, Process Systems Engineering, Sandtorstrasse 1, 39106, Magdeburg, Germany
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Theory and Bio-Systems, Science Park Golm, 14424, Potsdam, Germany
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11
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Fusion assays for model membranes: a critical review. ADVANCES IN BIOMEMBRANES AND LIPID SELF-ASSEMBLY 2019. [DOI: 10.1016/bs.abl.2019.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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12
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Bolognesi G, Friddin MS, Salehi-Reyhani A, Barlow NE, Brooks NJ, Ces O, Elani Y. Sculpting and fusing biomimetic vesicle networks using optical tweezers. Nat Commun 2018; 9:1882. [PMID: 29760422 PMCID: PMC5951844 DOI: 10.1038/s41467-018-04282-w] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 04/10/2018] [Indexed: 11/16/2022] Open
Abstract
Constructing higher-order vesicle assemblies has discipline-spanning potential from responsive soft-matter materials to artificial cell networks in synthetic biology. This potential is ultimately derived from the ability to compartmentalise and order chemical species in space. To unlock such applications, spatial organisation of vesicles in relation to one another must be controlled, and techniques to deliver cargo to compartments developed. Herein, we use optical tweezers to assemble, reconfigure and dismantle networks of cell-sized vesicles that, in different experimental scenarios, we engineer to exhibit several interesting properties. Vesicles are connected through double-bilayer junctions formed via electrostatically controlled adhesion. Chemically distinct vesicles are linked across length scales, from several nanometres to hundreds of micrometres, by axon-like tethers. In the former regime, patterning membranes with proteins and nanoparticles facilitates material exchange between compartments and enables laser-triggered vesicle merging. This allows us to mix and dilute content, and to initiate protein expression by delivering biomolecular reaction components. Assembly of higher-order artificial vesicles can unlock new applications. Here, the authors use optical tweezers to construct user-defined 2D and 3D architectures of chemically distinct vesicles and demonstrate inter-vesicle communication and light-enabled compartment merging.
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Affiliation(s)
- Guido Bolognesi
- Department of Chemical Engineering, Loughborough University, Loughborough, LE11 3TU, UK
| | - Mark S Friddin
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Ali Salehi-Reyhani
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.,Institute of Chemical Biology, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.,FABRICELL, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Nathan E Barlow
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Nicholas J Brooks
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.,Institute of Chemical Biology, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Oscar Ces
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK. .,Institute of Chemical Biology, Imperial College London, Exhibition Road, London, SW7 2AZ, UK. .,FABRICELL, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
| | - Yuval Elani
- Department of Chemistry, Imperial College London, Exhibition Road, London, SW7 2AZ, UK. .,Institute of Chemical Biology, Imperial College London, Exhibition Road, London, SW7 2AZ, UK. .,FABRICELL, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
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13
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Heo P, Park JB, Shin YK, Kweon DH. Visualization of SNARE-Mediated Hemifusion between Giant Unilamellar Vesicles Arrested by Myricetin. Front Mol Neurosci 2017; 10:93. [PMID: 28408867 PMCID: PMC5374201 DOI: 10.3389/fnmol.2017.00093] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/20/2017] [Indexed: 11/13/2022] Open
Abstract
Neurotransmitters are released within a millisecond after Ca2+ arrives at an active zone. However, the vesicle fusion pathway underlying this synchronous release is yet to be understood. At the center of controversy is whether hemifusion, in which outer leaflets are merged while inner leaflets are still separated, is an on-pathway or off-pathway product of Ca2+-triggered exocytosis. Using the single vesicle fusion assay, we recently demonstrated that hemifusion is an on-pathway intermediate that immediately proceeds to full fusion upon Ca2+ triggering. It has been shown that the flavonoid myricetin arrests soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein receptor (SNARE)-mediated vesicle fusion at hemifusion, but that the hemifused vesicles spontaneously convert to full fusion when the myricetin clamp is removed by the enzyme laccase. In the present study, we visualized SNARE-mediated hemifusion between two SNARE-reconstituted giant unilamellar vesicles (GUVs) arrested by myricetin. The large size of the GUVs enabled us to directly image the hemifusion between them. When two merging GUVs were labeled with different fluorescent dyes, GUV pairs showed asymmetric fluorescence intensities depending on the position on the GUV pair consistent with what is expected for hemifusion. The flow of lipids from one vesicle to the other was revealed with fluorescence recovery after photobleaching (FRAP), indicating that the two membranes had hemifused. These results support the hypothesis that hemifusion may be the molecular status that primes Ca2+-triggered millisecond exocytosis. This study represents the first imaging of SNARE-driven hemifusion between GUVs.
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Affiliation(s)
- Paul Heo
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan UniversitySuwon, South Korea
| | - Joon-Bum Park
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan UniversitySuwon, South Korea
| | - Yeon-Kyun Shin
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State UniversityAmes, IA, USA
| | - Dae-Hyuk Kweon
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan UniversitySuwon, South Korea
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14
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Smrt ST, Lorieau JL. Membrane Fusion and Infection of the Influenza Hemagglutinin. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 966:37-54. [PMID: 27966108 DOI: 10.1007/5584_2016_174] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The influenza virus is a major health concern associated with an estimated 5000 to 30,000 deaths every year (Reed et al. 2015) and a significant economic impact with the development of treatments, vaccinations and research (Molinari et al. 2007). The entirety of the influenza genome is comprised of only eleven coding genes. An enormous degree of variation in non-conserved regions leads to significant challenges in the development of inclusive inhibitors for treatment. The fusion peptide domain of the influenza A hemagglutinin (HA) is a promising candidate for treatment since it is one of the most highly conserved sequences in the influenza genome (Heiny et al. 2007), and it is vital to the viral life cycle. Hemagglutinin is a class I viral fusion protein that catalyzes the membrane fusion process during cellular entry and infection. Impediment of the hemagglutinin's function, either through incomplete post-translational processing (Klenk et al. 1975; Lazarowitz and Choppin 1975) or through mutations (Cross et al. 2001), leads to non-infective virus particles. This review will investigate current research on the role of hemagglutinin in the virus life cycle, its structural biology and mechanism as well as the central role of the hemagglutinin fusion peptide (HAfp) to influenza membrane fusion and infection.
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Affiliation(s)
- Sean T Smrt
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Justin L Lorieau
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, 60607, USA.
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15
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Sakuma Y, Imai M. From vesicles to protocells: the roles of amphiphilic molecules. Life (Basel) 2015; 5:651-75. [PMID: 25738256 PMCID: PMC4390873 DOI: 10.3390/life5010651] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 02/11/2015] [Accepted: 02/24/2015] [Indexed: 02/05/2023] Open
Abstract
It is very challenging to construct protocells from molecular assemblies. An important step in this challenge is the achievement of vesicle dynamics that are relevant to cellular functions, such as membrane trafficking and self-reproduction, using amphiphilic molecules. Soft matter physics will play an important role in the development of vesicles that have these functions. Here, we show that simple binary phospholipid vesicles have the potential to reproduce the relevant functions of adhesion, pore formation and self-reproduction of vesicles, by coupling the lipid geometries (spontaneous curvatures) and the phase separation. This achievement will elucidate the pathway from molecular assembly to cellular life.
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Affiliation(s)
- Yuka Sakuma
- Department of Physics, Tohoku University, Aoba, Sendai 980-8578, Japan.
| | - Masayuki Imai
- Department of Physics, Tohoku University, Aoba, Sendai 980-8578, Japan.
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16
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Kogan M, Feng B, Nordén B, Rocha S, Beke-Somfai T. Shear-induced membrane fusion in viscous solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:4875-4878. [PMID: 24758573 DOI: 10.1021/la404857r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Large unilamellar lipid vesicles do not normally fuse under fluid shear stress. They might deform and open pores to relax the tension to which they are exposed, but membrane fusion occurring solely due to shear stress has not yet been reported. We present evidence that shear forces in a viscous solution can induce lipid bilayer fusion. The fusion of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) liposomes is observed in Couette flow with shear rates above 3000 s(-1) provided that the medium is viscous enough. Liposome samples, prepared at different viscosities using a 0-50 wt % range of sucrose concentration, were studied by dynamic light scattering, lipid fusion assays using Förster resonance energy transfer (FRET), and linear dichroism (LD) spectroscopy. Liposomes in solutions with 40 wt % (or more) sucrose showed lipid fusion under shear forces. These results support the hypothesis that under suitable conditions lipid membranes may fuse in response to mechanical-force-induced stress.
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Affiliation(s)
- Maxim Kogan
- Department of Chemical and Biological Engineering, Physical Chemistry, Chalmers University of Technology , SE-412 96 Gothenburg, Sweden
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17
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Raudino A, Marrink SJ, Pannuzzo M. Anomalous viscosity effect in the early stages of the ion-assisted adhesion/fusion event between lipid bilayers: a theoretical and computational study. J Chem Phys 2014; 138:234901. [PMID: 23802979 DOI: 10.1063/1.4809993] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effect of viscosity on the encounter rate of two interacting membranes was investigated by combining a non-equilibrium Fokker-Planck model together with extensive Molecular Dynamics (MD) calculations. The encounter probability and stabilization of transient contact points represent the preliminary steps toward short-range adhesion and fusion of lipid leaflets. To strengthen our analytical model, we used a Coarse Grained MD method to follow the behavior of two charged palmitoyl oleoyl phosphatidylglycerol membranes embedded in a electrolyte-containing box at different viscosity regimes. Solvent friction was modulated by varying the concentration of a neutral, water-soluble polymer, polyethylene glycol, while contact points were stabilized by divalent ions that form bridges among juxtaposed membranes. While a naïve picture foresees a monotonous decrease of the membranes encounter rate with solvent viscosity, both the analytical model and MD simulations show a complex behavior. Under particular conditions, the encounter rate could exhibit a maximum at a critical viscosity value or for a critical concentration of bridging ions. These results seem to be confirmed by experimental observations taken from the literature.
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Affiliation(s)
- Antonio Raudino
- Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6, 95125 Catania, Italy.
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18
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Montis C, Baglioni P, Berti D. Monitoring the interaction of nucleolipoplexes with model membranes. SOFT MATTER 2014; 10:39-43. [PMID: 24651954 DOI: 10.1039/c3sm52254g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on the interaction of nucleolipid/DNA assemblies with model membranes, studied with small angle X-ray scattering, fluorescence microscopy and correlation spectroscopy. The fusion with the membrane can be monitored by following the diffusion properties of a lipid probe, shedding light on the parameters that regulate the internalization of the complexes.
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Affiliation(s)
- Costanza Montis
- CSGI and Department of Chemistry, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Firenze, Italy.
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19
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Giustini M, Giuliani AM, Gennaro G. Natural or synthetic nucleic acids encapsulated in a closed cavity of amphiphiles. RSC Adv 2013. [DOI: 10.1039/c3ra23208e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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20
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General hydrophobic interaction potential for surfactant/lipid bilayers from direct force measurements between light-modulated bilayers. Proc Natl Acad Sci U S A 2011; 108:15699-704. [PMID: 21896718 DOI: 10.1073/pnas.1112411108] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We establish and quantify correlations among the molecular structures, interaction forces, and physical processes associated with light-responsive self-assembled surfactant monolayers or bilayers at interfaces. Using the surface forces apparatus (SFA), the interaction forces between adsorbed monolayers and bilayers of an azobenzene-functionalized surfactant can be drastically and controllably altered by light-induced conversion of trans and cis molecular conformations. These reversible conformation changes affect significantly the shape of the molecules, especially in the hydrophobic region, which induces dramatic transformations of molecular packing in self-assembled structures, causing corresponding modulation of electrostatic double layer, steric hydration, and hydrophobic interactions. For bilayers, the isomerization from trans to cis exposes more hydrophobic groups, making the cis bilayers more hydrophobic, which lowers the activation energy barrier for (hemi)fusion. A quantitative and general model is derived for the interaction potential of charged bilayers that includes the electrostatic double-layer force of the Derjaguin-Landau-Verwey-Overbeek theory, attractive hydrophobic interactions, and repulsive steric-hydration forces. The model quantitatively accounts for the elastic strains, deformations, long-range forces, energy maxima, adhesion minima, as well as the instability (when it exists) as two bilayers breakthrough and (hemi)fuse. These results have several important implications, including quantitative and qualitative understanding of the hydrophobic interaction, which is furthermore shown to be a nonadditive interaction.
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21
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The effect of long-chain bases on polysialic acid-mediated membrane interactions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2322-6. [DOI: 10.1016/j.bbamem.2011.05.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Revised: 05/04/2011] [Accepted: 05/10/2011] [Indexed: 11/20/2022]
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22
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Sun Y, Lee CC, Huang HW. Adhesion and merging of lipid bilayers: a method for measuring the free energy of adhesion and hemifusion. Biophys J 2011; 100:987-95. [PMID: 21320443 DOI: 10.1016/j.bpj.2011.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 01/06/2011] [Accepted: 01/10/2011] [Indexed: 10/18/2022] Open
Abstract
Lipid bilayers can be induced to adhere to each other by molecular mediators, and, depending on the lipid composition, such adhesion can lead to merging of the contacting monolayers in a process known as hemifusion. Such bilayer-bilayer reactions have never been systematically studied. In the course of our studies of membrane-active molecules, we encountered such reactions. We believe that they need to be understood whenever bilayer-bilayer interactions take place, such as during membrane fusion. For illustration, we discuss three examples: spontaneous adhesion between phospholipid bilayers induced by low pH, polymer-induced osmotic depletion attraction between lipid bilayers, and anionic lipid bilayers cross-bridged by multicationic peptides. Our purpose here is to describe a general method for studying such interactions. We used giant unilamellar vesicles, each of which was aspirated in a micropipette so that we could monitor the tension of the membrane and the membrane area changes during the bilayer-bilayer interaction. We devised a general method for measuring the free energy of adhesion or hemifusion. The results show that the energies of adhesion or hemifusion of lipid bilayers could vary over 2 orders of magnitude from -1 to -50 × 10(-5) J/m(2) in these examples alone. Our method can be used to measure the energy of transition in each step of lipid transformation during membrane fusion. This is relevant for current research on membrane fusion, which focuses on how fusion proteins induce lipid transformations.
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Affiliation(s)
- Yen Sun
- Department of Physics and Astronomy, Rice University, Houston, Texas, USA
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23
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Pascal D, Valérie R, Stefan W, Remy O, Louise CM, Pauline H, Alain M, Justin T. Targeted Macromolecules Delivery by Large Lipidic Nanovesicles Electrofusion with Mammalian Cells. ACTA ACUST UNITED AC 2011. [DOI: 10.4236/jbnb.2011.225063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Nikolaus J, Warner JM, O'Shaughnessy B, Herrmann A. The pathway to membrane fusion through hemifusion. CURRENT TOPICS IN MEMBRANES 2011; 68:1-32. [PMID: 21771493 DOI: 10.1016/b978-0-12-385891-7.00001-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jörg Nikolaus
- Department of Biology, Faculty of Mathematics and Natural Sciences I, Humboldt-University Berlin, Berlin, Germany
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25
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Nikolaus J, Stöckl M, Langosch D, Volkmer R, Herrmann A. Direct visualization of large and protein-free hemifusion diaphragms. Biophys J 2010; 98:1192-9. [PMID: 20371318 DOI: 10.1016/j.bpj.2009.11.042] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 11/12/2009] [Accepted: 11/12/2009] [Indexed: 10/19/2022] Open
Abstract
Fusion of cellular membranes is a ubiquitous biological process requiring remodeling of two phospholipid bilayers. We believe it is very likely that merging of membranes proceeds via similar sequential intermediates. Contacting membranes form a stalk between the proximal leaflets that expands radially into an hemifusion diaphragm (HD) and subsequently open to a fusion pore. Although considered to be a key intermediate in fusion, direct experimental verification of this structure is difficult due to its transient nature. Using confocal fluorescence microscopy we have investigated the fusion of giant unilamellar vesicles (GUVs) containing phosphatidylserine and fluorescent virus derived transmembrane peptides or membrane proteins in the presence of divalent cations. Time-resolved imaging revealed that fusion was preceded by displacement of peptides and fluorescent lipid analogs from the GUV-GUV adhesion region. A detailed analysis of this area being several mum in size revealed that peptides were completely sequestered as expected for an HD. Lateral distribution of lipid analogs was consistent with formation of an HD but not with the presence of two adherent bilayers. Formation and size of the HD were dependent on lipid composition and peptide concentration.
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Affiliation(s)
- Jörg Nikolaus
- Institute of Biology, Faculty of Mathematics and Natural Sciences, Humboldt-University Berlin, Berlin, Germany
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26
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Walde P, Cosentino K, Engel H, Stano P. Giant Vesicles: Preparations and Applications. Chembiochem 2010; 11:848-65. [DOI: 10.1002/cbic.201000010] [Citation(s) in RCA: 556] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Raudino A, Pannuzzo M. Nucleation theory with delayed interactions: An application to the early stages of the receptor-mediated adhesion/fusion kinetics of lipid vesicles. J Chem Phys 2010; 132:045103. [DOI: 10.1063/1.3290823] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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28
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Loew M, Kang J, Dähne L, Hendus-Altenburger R, Kaczmarek O, Liebscher J, Huster D, Ludwig K, Böttcher C, Herrmann A, Arbuzova A. Controlled assembly of vesicle-based nanocontainers on layer-by-layer particles via DNA hybridization. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:320-323. [PMID: 19123173 DOI: 10.1002/smll.200800989] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- Martin Loew
- Institut für Biologie/Biophysik, Humboldt-Universität zu Berlin, Berlin, Germany
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29
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Abstract
SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins have a key role in membrane fusion. It is commonly assumed that pairing of SNARE proteins anchored in opposing membranes overcomes the repulsion energy between membranes, thereby catalyzing fusion. In this study, we have increased the distance between the coiled-coil SNARE motif and the transmembrane domain of the vesicular SNARE synaptobrevin-2 by insertion of a flexible linker to analyze how an increased intermembrane distance affects exocytosis. Synaptobrevin-2 lengthening did not change the frequency of exocytotic events measured at 1 mum free calcium but prevented the increase in the secretory activity triggered by higher calcium concentration. Exocytotic events monitored in adrenal chromaffin cells by means of carbon fiber amperometry were classified in two groups according to the rate and extent of fusion pore expansion. Lengthening the juxtamembrane region of synaptobrevin-2 severely reduced the occurrence of rapid single events, leaving slow ones unchanged. It also impaired the increase in the fast-fusion mode that normally follows elevation of intracellular Ca2+ levels. We conclude that mild stimuli trigger slow fusion events that do not rely on a short intermembrane distance. In contrast, a short intermembrane distance mediated by tight zippering of SNAREs is essential to a component of the secretory response elicited by robust stimuli and characterized by rapid dilation of the fusion pore.
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30
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The overall adhesion-spreading process of liposomes on a mercury electrode is controlled by a mixed diffusion and reaction kinetics mechanism. J Solid State Electrochem 2008. [DOI: 10.1007/s10008-008-0639-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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31
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Sakuma Y, Imai M, Yanagisawa M, Komura S. Adhesion of binary giant vesicles containing negative spontaneous curvature lipids induced by phase separation. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2008; 25:403-413. [PMID: 18418545 DOI: 10.1140/epje/i2007-10307-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Accepted: 02/29/2008] [Indexed: 05/26/2023]
Abstract
We report the adhesion of binary giant vesicles composed of two types of phospholipids, one has negative spontaneous curvature which tends to bend toward the head group and the other has zero spontaneous curvature. In a homogeneous one-phase region, the giant vesicles do not adhere to each other, whereas in a coexisting two-phase region, the giant vesicles show adhesion. A fluorescence microscope observation reveals that the adhesion takes place through the domains rich in phospholipids having negative spontaneous curvature. We propose a phase separation induced hemifusion model where two apposed monolayers of adjacent vesicles are hemifused in order to reduce the bending energy of monolayers with negative spontaneous curvature and the boundary energy between the domains and matrix. We provide a strong evidence for the hemifusion model by lipid transfer experiments.
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Affiliation(s)
- Y Sakuma
- Department of Physics, Ochanomizu University, Tokyo, Japan
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32
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Beales PA, Vanderlick TK. Specific Binding of Different Vesicle Populations by the Hybridization of Membrane-Anchored DNA. J Phys Chem A 2007; 111:12372-80. [DOI: 10.1021/jp075792z] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Paul A. Beales
- Department of Chemical Engineering, Princeton University, Princeton, New Jersey 08544
| | - T. Kyle Vanderlick
- Department of Chemical Engineering, Princeton University, Princeton, New Jersey 08544
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Abstract
Many different hypotheses on the molecular mechanisms of vesicle fusion exist. Because these mechanisms cannot be readily asserted experimentally, we address the problem by a coarse-grained molecular dynamics simulations study and compare the results with the results of other techniques. The simulations performed include the fusion of small and large vesicles and exocytosis, i.e., the fusion of small vesicles with flat bilayers. We demonstrate that the stalk, the initial contact between two fusing vesicles, is initiated by lipid tails that extend spontaneously. The stalk is revealed to be composed of the contacting monolayers only, yet without hydrophobic voids. Anisotropic and radial expansion of the stalk have been theorized; we show that stalk evolution can proceed via both pathways starting from similar setups and that water triggers the transition from elongated stalk to hemifusion diaphragm.
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Affiliation(s)
- A F Smeijers
- Department of Biomedical Engineering, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
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34
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Su W, Luo Y, Yan Q, Wu S, Han K, Zhang Q, Gu Y, Li Y. Photoinduced Fusion of Micro-Vesicles Self-Assembled from Azobenzene-Containing Amphiphilic Diblock Copolymers. Macromol Rapid Commun 2007. [DOI: 10.1002/marc.200700077] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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35
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Zhou Y, Berry CK, Storer PA, Raphael RM. Peroxidation of polyunsaturated phosphatidyl-choline lipids during electroformation. Biomaterials 2007; 28:1298-306. [PMID: 17107709 DOI: 10.1016/j.biomaterials.2006.10.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Accepted: 10/09/2006] [Indexed: 10/23/2022]
Abstract
Giant unilamellar vesicles (GUVs) have been utilized both as model systems to study the physico-chemical properties of biomembranes and as host materials for investigating biological processes in microbioreactors. GUVs are commonly formed by an electroformation technique. However, there is a concern that the electric fields applied during electroformation can peroxidize lipid acyl chains, thereby altering the phospholipid composition and material properties of the synthesized vesicles. Here in this paper, we report the effect of electroformation on the extent of peroxidation of a number of polyunsaturated phosphatidyl-choline lipids (PULs). Specifically, we detected peroxidation byproducts (malonaldehydes and conjugated dienes) of the following lipids utilizing UV/Vis spectroscopy: dilinoleoyl phosphatidyl-choline (DLPC) (di-18:2 PC), dilinolenoyl phosphatidyl-choline (DNPC) (di-18:3 PC), diarachidonoyl phosphatidyl-choline (DAPC) (di-20:4 PC), and didocosaheexaenoyl phosphatidyl-choline (DHA) (di-22:6 PC). The results indicate that PC PULs lipids are prone to peroxidation, with increasing unsaturation levels leading to higher levels of peroxidation byproducts. The levels of peroxidation byproducts of DAPC were found to depend linearly on the strength of the electric field, indicating that the observed effects were due to the applied electric field. Lipid peroxidation can affect a number of important membrane properties, including domain formation and mechanical stability. Thus, alteration of the chemical composition of polyunsaturated lipids (PULs) by the electroformation technique can potentially complicate the interpretation of experimental studies that utilize GUVs composed of PULs.
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Affiliation(s)
- Yong Zhou
- The Department of Biochemistry and Cell Biology, Rice University, Houston, TX, USA
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36
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Solon J, Pécréaux J, Girard P, Fauré MC, Prost J, Bassereau P. Negative tension induced by lipid uptake. PHYSICAL REVIEW LETTERS 2006; 97:098103. [PMID: 17026406 DOI: 10.1103/physrevlett.97.098103] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Indexed: 05/12/2023]
Abstract
Membrane fusion is an important process in cell biology. While the molecular mechanisms of fusion are actively studied at a very local scale, the consequences of fusion at a larger scale on the shape and stability of the membrane are still not explored. In this Letter, the evolution of the membrane tension during the fusion of positive small unilamellar vesicles with a negative giant unilamellar vesicle has been experimentally investigated and compared to an existing theoretical model. The tension has been deduced using videomicroscopy from the measurement of the fluctuation spectrum and of the time correlation function of the fluctuations. We show that fusion induces a strong decrease in the effective tension of the membrane which eventually reaches negative values. Under these conditions, we show that localized instabilities appear on the vesicle. The membrane finally collapses, forming dense lipid structures.
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Affiliation(s)
- Jérôme Solon
- Institut Curie, UMR CNRS 168, 75248 Paris, France
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37
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Estes DJ, Lopez SR, Fuller AO, Mayer M. Triggering and visualizing the aggregation and fusion of lipid membranes in microfluidic chambers. Biophys J 2006; 91:233-43. [PMID: 16617088 PMCID: PMC1479077 DOI: 10.1529/biophysj.105.076398] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Accepted: 04/05/2006] [Indexed: 11/18/2022] Open
Abstract
We present a method that makes it possible to trigger, observe, and quantify membrane aggregation and fusion of giant liposomes in microfluidic chambers. Using electroformation from spin-coated films of lipids on transparent indium tin oxide electrodes, we formed two-dimensional networks of closely packed, surface-attached giant liposomes. We investigated the effects of fusogenic agents by simply flowing these molecules into the chambers and analyzing the resulting shape changes of more than 100 liposomes in parallel. We used this setup to quantify membrane fusion by several well-studied mechanisms, including fusion triggered by Ca2+, polyethylene glycol, and biospecific tethering. Directly observing many liposomes simultaneously proved particularly useful for studying fusion events in the presence of low concentrations of fusogenic agents, when fusion was rare and probabilistic. We applied this microfluidic fusion assay to investigate a novel 30-mer peptide derived from a recently identified human receptor protein, B5, that is important for membrane fusion during the entry of herpes simplex virus into host cells. This peptide triggered fusion of liposomes at an approximately 6 times higher probability than control peptides and caused irreversible interactions between adjacent membranes; it was, however, less fusogenic than Ca2+ at comparable concentrations. Closely packed, surface-attached giant liposomes in microfluidic chambers offer a method to observe membrane aggregation and fusion in parallel without requiring the use of micromanipulators. This technique makes it possible to characterize rapidly novel fusogenic agents under well-defined conditions.
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Affiliation(s)
- Daniel J Estes
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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38
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Smeijers AF, Pieterse K, Markvoort AJ, Hilbers PAJ. Coarse-Grained Transmembrane Proteins: Hydrophobic Matching, Aggregation, and Their Effect on Fusion. J Phys Chem B 2006; 110:13614-23. [PMID: 16821889 DOI: 10.1021/jp062012y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular transport between organelles is predominantly governed by vesicle fission and fusion. Unlike experimental vesicles, the fused vesicles in molecular dynamics simulations do not become spherical readily, because the lipid and water distribution is inappropriate for the fused state and spontaneous amendment is slow. Here, we study the hypothesis that enhanced transport across the membrane of water, lipids, or both is required to produce spherical vesicles. This is done by adding several kinds of model proteins to fusing vesicles. The results show that equilibration of both water and lipid content is a requirement for spherical vesicles. In addition, the effect of these transmembrane proteins is studied in bilayers and vesicles, including investigations into hydrophobic matching and aggregation. Our simulations show that the level of aggregation does not only depend on hydrophobic mismatch, but also on protein shape. Additionally, one of the proteins promotes fusion by inducing pore formation. Incorporation of these proteins allows even flat membranes to fuse spontaneously. Moreover, we encountered a novel spontaneous vesicle enlargement mechanism we call the engulfing lobe, which may explain how lipids added to a vesicle solution are quickly incorporated into the inner monolayer.
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Affiliation(s)
- A F Smeijers
- Department of Biomedical Engineering, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
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Rodriguez N, Heuvingh J, Pincet F, Cribier S. Indirect evidence of submicroscopic pores in giant unilamellar [correction of unilamelar] vesicles. Biochim Biophys Acta Gen Subj 2005; 1724:281-7. [PMID: 15978732 DOI: 10.1016/j.bbagen.2005.04.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Revised: 04/24/2005] [Accepted: 04/26/2005] [Indexed: 10/25/2022]
Abstract
Formation of pore-like structures in cell membranes could participate in exchange of matter between cell compartments and modify the lipid distribution between the leaflets of a bilayer. We present experiments on two model systems in which major lipid redistribution is attributed to few submicroscopic transient pores. The first kind of experiments consists in destabilizing the membrane of a giant unilamellar vesicle by inserting conic-shaped fluorescent lipids from the outer medium. The inserted lipids (10% of the vesicle lipids) should lead to membrane rupture if segregated on the outer leaflet. We show that a 5-nm diameter pore is sufficient to ease the stress on the membrane by redistributing the lipids. The second kind of experiments consists in forcing giant vesicles containing functionalized lipids to adhere. This adhesion leads to hemifusion (merging of the outer leaflets). In certain cases, the formation of pores in one of the vesicles is attested by contrast loss on this vesicle and redistribution of fluorescent labels between the leaflets. The kinetics of these phenomena is compatible with transient submicroscopic pores and long-lived membrane defects.
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Affiliation(s)
- N Rodriguez
- Laboratoire de Physico-Chimie Moléculaire des Membranes Biologiques, UMR7099, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris, France
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