1
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Nicolella Z, Okamoto Y, Watanabe NM, Thompson GL, Umakoshi H. Significance of in situ quantitative membrane property-morphology relation (QmPMR) analysis. SOFT MATTER 2024; 20:4935-4949. [PMID: 38873752 DOI: 10.1039/d4sm00253a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
Deformation of the cell membrane is well understood from the viewpoint of protein interactions and free energy balance. However, the various dynamic properties of the membrane, such as lipid packing and hydrophobicity, and their relationship with cell membrane deformation are unknown. Therefore, the deformation of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and oleic acid (OA) giant unilamellar vesicles (GUVs) was induced by heating and cooling cycles, and time-lapse analysis was conducted based on the membrane hydrophobicity and physical parameters of "single-parent" and "daughter" vesicles. Fluorescence ratiometric analysis by simultaneous dual-wavelength detection revealed the variation of different hydrophilic GUVs and enabled inferences of the "daughter" vesicle composition and the "parent" membrane's local composition during deformation; the "daughter" vesicle composition of OA was lower than that of the "parents", and lateral movement of OA was the primary contributor to the formation of the "daughter" vesicles. Thus, our findings and the newly developed methodology, named in situ quantitative membrane property-morphology relation (QmPMR) analysis, would provide new insights into cell deformation and accelerate research on both deformation and its related events, such as budding and birthing.
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Affiliation(s)
- Zachary Nicolella
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
| | - Nozomi Morishita Watanabe
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
| | - Gary Lee Thompson
- Rowan University, Rowan Hall, Room 333 70 Sewell St., Ste. E Glassboro, NJ 08028, USA
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
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2
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Lauritsen L, Szomek M, Hornum M, Reinholdt P, Kongsted J, Nielsen P, Brewer JR, Wüstner D. Ratiometric fluorescence nanoscopy and lifetime imaging of novel Nile Red analogs for analysis of membrane packing in living cells. Sci Rep 2024; 14:13748. [PMID: 38877068 PMCID: PMC11178856 DOI: 10.1038/s41598-024-64180-8] [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: 12/18/2023] [Accepted: 06/05/2024] [Indexed: 06/16/2024] Open
Abstract
Subcellular membranes have complex lipid and protein compositions, which give rise to organelle-specific membrane packing, fluidity, and permeability. Due to its exquisite solvent sensitivity, the lipophilic fluorescence dye Nile Red has been used extensively to study membrane packing and polarity. Further improvement of Nile Red can be achieved by introducing electron-donating or withdrawing functional groups. Here, we compare the potential of derivatives of Nile Red with such functional substitutions for super-resolution fluorescence microscopy of lipid packing in model membranes and living cells. All studied Nile Red derivatives exhibit cholesterol-dependent fluorescence changes in model membranes, as shown by spectrally resolved stimulated emission depletion (STED) microscopy. STED imaging of Nile Red probes in cells reveals lower membrane packing in fibroblasts from healthy subjects compared to those from patients suffering from Niemann Pick type C1 (NPC1) disease, a lysosomal storage disorder with accumulation of cholesterol and sphingolipids in late endosomes and lysosomes. We also find small but consistent changes in the fluorescence lifetime of the Nile Red derivatives in NPC1 cells, suggesting altered hydrogen-bonding capacity in their membranes. All Nile Red derivatives are essentially non-fluorescent in water but increase their brightness in membranes, allowing for their use in MINFLUX single molecule tracking experiments. Our study uncovers the potential of Nile Red probes with functional substitutions for nanoscopic membrane imaging.
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Affiliation(s)
- Line Lauritsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Maria Szomek
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Mick Hornum
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Peter Reinholdt
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Poul Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Jonathan R Brewer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Daniel Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.
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3
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Saha Roy D, Gupta A, Vishvakarma V, Krupa P, Li MS, Maiti S. Serotonin Promotes Vesicular Association and Fusion by Modifying Lipid Bilayers. J Phys Chem B 2024; 128:4975-4985. [PMID: 38743687 DOI: 10.1021/acs.jpcb.4c00115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The primary event in chemical neurotransmission involves the fusion of a membrane-limited vesicle at the plasma membrane and the subsequent release of its chemical neurotransmitter cargo. The cargo itself is not known to have any effect on the fusion event. However, amphiphilic monoamine neurotransmitters (e.g., serotonin and dopamine) are known to strongly interact with lipid bilayers and to affect their mechanical properties, which can in principle impact membrane-mediated processes. Here, we probe whether serotonin can enhance the association and fusion of artificial lipid vesicles in vitro. We employ fluorescence correlation spectroscopy and total internal reflection fluorescence microscopy to measure the attachment and fusion of vesicles whose lipid compositions mimic the major lipid components of synaptic vesicles. We find that the association between vesicles and supported lipid bilayers is strongly enhanced in a serotonin dose-dependent manner, and this drives an increase in the rate of spontaneous fusion. Molecular dynamics simulations and fluorescence spectroscopy data show that serotonin insertion increases the water content of the hydrophobic part of the bilayer. This suggests that the enhanced membrane association is likely driven by an energetically favorable drying transition. Other monoamines, such as dopamine and norepinephrine, but not other related species, such as tryptophan, show similar effects on membrane association. Our results reveal a lipid bilayer-mediated mechanism by which monoamines can themselves modulate vesicle fusion, potentially adding to the control toolbox for the tightly regulated process of neurotransmission in vivo.
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Affiliation(s)
- Debsankar Saha Roy
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Ankur Gupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Vicky Vishvakarma
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Pawel Krupa
- Institute of Physics, Polish Academy of Sciences, Warsaw 02-668, Poland
| | - Mai Suan Li
- Institute of Physics, Polish Academy of Sciences, Warsaw 02-668, Poland
- Institute for Computational Science and Technology, Quang Trung Software City, Tan Chanh Hiep Ward, District 12, 729110 Ho Chi Minh City, Vietnam
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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4
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Gudyka J, Ceja-Vega J, Ivanchenko K, Perla W, Poust C, Gamez Hernandez A, Clarke C, Silverberg S, Perez E, Lee S. Differential Effects of Soy Isoflavones on the Biophysical Properties of Model Membranes. J Phys Chem B 2024; 128:2412-2424. [PMID: 38417149 PMCID: PMC10945484 DOI: 10.1021/acs.jpcb.3c08390] [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: 12/24/2023] [Revised: 02/12/2024] [Accepted: 02/16/2024] [Indexed: 03/01/2024]
Abstract
The effects that the main soy isoflavones, genistein and daidzein, have upon the biophysical properties of a model lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or DOPC with cholesterol (4 to 1 mol ratio) have been investigated by transbilayer water permeability, differential scanning calorimetry, and confocal Raman microspectroscopy. Genistein is found to increase water permeability, decrease phase transition temperature, reduce enthalpy of transition, and induce packing disorder in the DOPC membrane with an increasing concentration. On the contrary, daidzein decreases water permeability and shows negligible impact on thermodynamic parameters and packing disorder at comparable concentrations. For a cholesterol-containing DOPC bilayer, both genistein and daidzein exhibit an overall less pronounced effect on transbilayer water permeability. Their respective differential abilities to modify the physical and structural properties of biomembranes with varying lipid compositions signify a complex and sensitive nature to isoflavone interactions, which depends on the initial state of bilayer packing and the differences in the molecular structures of these soy isoflavones, and provide insights in understanding the interactions of these molecules with cellular membranes.
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Affiliation(s)
- Jamie Gudyka
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Jasmin Ceja-Vega
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Katherine Ivanchenko
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Wilber Perla
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Christopher Poust
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Alondra Gamez Hernandez
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Colleen Clarke
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Shakinah Silverberg
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Escarlin Perez
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
| | - Sunghee Lee
- Department of Chemistry and
Biochemistry, Iona University, 715 North Avenue, New Rochelle, New York 10801, United States
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5
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Ragaller F, Sjule E, Urem YB, Schlegel J, El R, Urbancic D, Urbancic I, Blom H, Sezgin E. Quantifying Fluorescence Lifetime Responsiveness of Environment-Sensitive Probes for Membrane Fluidity Measurements. J Phys Chem B 2024; 128:2154-2167. [PMID: 38415644 PMCID: PMC10926104 DOI: 10.1021/acs.jpcb.3c07006] [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: 10/23/2023] [Revised: 02/08/2024] [Accepted: 02/09/2024] [Indexed: 02/29/2024]
Abstract
The structural diversity of different lipid species within the membrane defines its biophysical properties such as membrane fluidity, phase transition, curvature, charge distribution, and tension. Environment-sensitive probes, which change their spectral properties in response to their surrounding milieu, have greatly contributed to our understanding of such biophysical properties. To realize the full potential of these probes and avoid misinterpretation of their spectral responses, a detailed investigation of their fluorescence characteristics in different environments is necessary. Here, we examined the fluorescence lifetime of two newly developed membrane order probes, NR12S and NR12A, in response to alterations in their environments such as the degree of lipid saturation, cholesterol content, double bond position and configuration, and phospholipid headgroup. As a comparison, we investigated the lifetime sensitivity of the membrane tension probe Flipper in these environments. Applying fluorescence lifetime imaging microscopy (FLIM) in both model membranes and biological membranes, all probes distinguished membrane phases by lifetime but exhibited different lifetime sensitivities to varying membrane biophysical properties (e.g., cholesterol). While the lifetime of Flipper is particularly sensitive to the membrane cholesterol content, the NR12S and NR12A lifetimes are moderately sensitive to both the cholesterol content and lipid acyl chains. Moreover, all of the probes exhibit longer lifetimes at longer emission wavelengths in membranes of any complexity. This emission wavelength dependency results in varying lifetime resolutions at different spectral regions, which are highly relevant for FLIM data acquisition. Our data provide valuable insights on how to perform FLIM with these probes and highlight both their potential and limitations.
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Affiliation(s)
- Franziska Ragaller
- Department
of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Ellen Sjule
- Department
of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Yagmur Balim Urem
- Department
of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Jan Schlegel
- Department
of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Rojbin El
- Weatherall
Institute of Molecular Medicine, University
of Oxford, OX39DS Oxford, United
Kingdom
| | - Dunja Urbancic
- Weatherall
Institute of Molecular Medicine, University
of Oxford, OX39DS Oxford, United
Kingdom
- Faculty
of Pharmacy, University
of Ljubljana, 1000 Ljubljana, Slovenia
| | - Iztok Urbancic
- Laboratory
of Biophysics, Condensed Matter Physics Department, Jožef Stefan Institute, 1000 Ljubljana, Slovenia
| | - Hans Blom
- Science
for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, 17165 Solna, Sweden
| | - Erdinc Sezgin
- Department
of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
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6
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Roy DS, Gozzi M, Engberg O, Adler J, Huster D, Maiti S. Membrane-Mediated Allosteric Action of Serotonin on a Noncognate G-Protein-Coupled Receptor. J Phys Chem Lett 2024; 15:1711-1718. [PMID: 38319949 DOI: 10.1021/acs.jpclett.3c02340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
The structure and dynamics of the lipid membrane can affect the activity of membrane proteins. Therefore, small lipophilic molecules that alter membrane properties (such as the neurotransmitter serotonin) can potentially modulate receptor activity without binding to the receptor. Here, we investigated how the activity of neuropeptide Y type 4 receptor (Y4R, reconstituted in lipid bicelles) is modulated by serotonin, which has no known interaction with Y4R. We found a serotonin-concentration-dependent decrease (down to 0.1 mM of serotonin) in the ligand affinity of Y4R. This effect correlates with a serotonin-induced reduction of the resistance of the bilayer to indentation (measured by atomic force microscopy) and bilayer thickness (measured by solid state NMR) in two different types of zwitterionic lipid bicelles. Our findings indicate a "membrane-mediated allosteric effect" of serotonin on the activation of Y4R and suggest the potential for developing pharmacophores, which can modulate cellular signaling without directly interacting with any receptor.
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Affiliation(s)
- Debsankar Saha Roy
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Marta Gozzi
- Institute of Medical Physics and Biophysics, Medical Department, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Oskar Engberg
- Institute of Medical Physics and Biophysics, Medical Department, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Juliane Adler
- Institute of Medical Physics and Biophysics, Medical Department, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Daniel Huster
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
- Institute of Medical Physics and Biophysics, Medical Department, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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7
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Roversi D, Troiano C, Salnikov E, Giordano L, Riccitelli F, De Zotti M, Casciaro B, Loffredo MR, Park Y, Formaggio F, Mangoni ML, Bechinger B, Stella L. Effects of antimicrobial peptides on membrane dynamics: A comparison of fluorescence and NMR experiments. Biophys Chem 2023; 300:107060. [PMID: 37336097 DOI: 10.1016/j.bpc.2023.107060] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/25/2023] [Accepted: 06/02/2023] [Indexed: 06/21/2023]
Abstract
Antimicrobial peptides (AMPs) represent a promising class of compounds to fight resistant infections. They are commonly thought to kill bacteria by perturbing the permeability of their cell membranes. However, bacterial killing requires a high coverage of the cell surface by bound peptides, at least in the case of cationic and amphipathic AMPs. Therefore, it is conceivable that peptide accumulation on the bacterial membranes might interfere with vital cellular functions also by perturbing bilayer dynamics, a hypothesis that has been termed "sand in the gearbox". Here we performed a systematic study of such possible effects, for two representative peptides (the cationic cathelicidin PMAP-23 and the peptaibol alamethicin), employing fluorescence and NMR spectroscopies. These approaches are commonly applied to characterize lipid order and dynamics, but sample different time-scales and could thus report on different membrane properties. In our case, fluorescence anisotropy measurements on liposomes labelled with probes localized at different depths in the bilayer showed that both peptides perturb membrane fluidity and order. Pyrene excimer-formation experiments showed a peptide-induced reduction in lipid lateral mobility. Finally, laurdan fluorescence indicated that peptide binding reduces water penetration below the headgroups region. Comparable effects were observed also in fluorescence experiments performed directly on live bacterial cells. By contrast, the fatty acyl chain order parameters detected by deuterium NMR spectroscopy remained virtually unaffected by addition of the peptides. The apparent discrepancy between the two techniques confirms previous sporadic observations and is discussed in terms of the different characteristic times of the two approaches. The perturbation of membrane dynamics in the ns timescale, indicated by the multiple fluorescence approaches reported here, could contribute to the antimicrobial activity of AMPs, by affecting the function of membrane proteins, which is strongly dependent on the physicochemical properties of the bilayer.
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Affiliation(s)
- Daniela Roversi
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Cassandra Troiano
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Evgeniy Salnikov
- RMN et Biophysique des membranes, Institut de Chimie de Strasbourg, CNRS/UMR 7177, Université de Strasbourg, 4, rue Blaise Pascal, Strasbourg 67000, France
| | - Lorenzo Giordano
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Francesco Riccitelli
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Marta De Zotti
- Department of Chemical Sciences, University of Padova, Padova 35131, Italy
| | - Bruno Casciaro
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Maria Rosa Loffredo
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Yoonkyung Park
- Department of Biomedical Science and Research Center for Proteinaceous Materials (RCPM), Chosun University, Gwangju, Republic of Korea
| | - Fernando Formaggio
- Department of Chemical Sciences, University of Padova, Padova 35131, Italy
| | - Maria Luisa Mangoni
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Burkhard Bechinger
- RMN et Biophysique des membranes, Institut de Chimie de Strasbourg, CNRS/UMR 7177, Université de Strasbourg, 4, rue Blaise Pascal, Strasbourg 67000, France; Institut Universitaire de France, Paris 75005, France
| | - Lorenzo Stella
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy.
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8
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Ward AE, Sokovikova D, Waxham MN, Heberle FA, Levental I, Levental KR, Kiessling V, White JM, Tamm LK. Serinc5 Restricts HIV Membrane Fusion by Altering Lipid Order and Heterogeneity in the Viral Membrane. ACS Infect Dis 2023; 9:773-784. [PMID: 36946615 PMCID: PMC10366416 DOI: 10.1021/acsinfecdis.2c00478] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
The host restriction factor, Serinc5, incorporates into budding HIV particles and inhibits their infection by an incompletely understood mechanism. We have previously reported that Serinc5 but not its paralogue, Serinc2, blocks HIV cell entry by membrane fusion, specifically by inhibiting fusion pore formation and dilation. A body of work suggests that Serinc5 may alter the conformation and clustering of the HIV fusion protein, Env. To contribute an additional perspective to the developing model of Serinc5 restriction, we assessed Serinc2 and Serinc5's effects on HIV pseudoviral membranes. By measuring pseudoviral membrane thickness via cryo-electron microscopy and order via the fluorescent dye, FLIPPER-TR, Serinc5 was found to increase membrane heterogeneity, skewing the distribution toward a larger fraction of the viral membrane in an ordered phase. We also directly observed for the first time the coexistence of membrane domains within individual viral membrane envelopes. Using a total internal reflection fluorescence-based single particle fusion assay, we found that treatment of HIV pseudoviral particles with phosphatidylethanolamine (PE) rescued HIV pseudovirus fusion from restriction by Serinc5, which was accompanied by decreased membrane heterogeneity and order. This effect was specific for PE and did not depend on acyl chain length or saturation. Together, these data suggest that Serinc5 alters multiple interrelated properties of the viral membrane─lipid chain order, rigidity, line tension, and lateral pressure─which decrease the accessibility of fusion intermediates and disfavor completion of fusion. These biophysical insights into Serinc5 restriction of HIV infectivity could contribute to the development of novel antivirals that exploit the same weaknesses.
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Affiliation(s)
- Amanda E. Ward
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
| | - Daria Sokovikova
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
| | - Melvin Neal Waxham
- Department of Neurobiology and Anatomy, The University of Texas Health Science Center at Houston McGovern Medical School, Houston, TX 77030
| | | | - Ilya Levental
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
| | - Kandice R. Levental
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
| | - Volker Kiessling
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
| | - Judith M. White
- Department of Cell Biology, University of Virginia Health System, Charlottesville, VA 22908
| | - Lukas K. Tamm
- Department of Molecular Physiology and Biological Physics, University of Virginia Health System, Charlottesville, VA 22908
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908
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9
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Gupta A, Krupa P, Engberg O, Krupa M, Chaudhary A, Li MS, Huster D, Maiti S. Unusual Robustness of Neurotransmitter Vesicle Membranes against Serotonin-Induced Perturbations. J Phys Chem B 2023; 127:1947-1955. [PMID: 36795947 DOI: 10.1021/acs.jpcb.2c07464] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Nature confines hundreds of millimolar of amphiphilic neurotransmitters, such as serotonin, in synaptic vesicles. This appears to be a puzzle, as the mechanical properties of lipid bilayer membranes of individual major polar lipid constituents of synaptic vesicles [phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS)] are significantly affected by serotonin, sometimes even at few millimolar concentrations. These properties are measured by atomic force microscopy, and their results are corroborated by molecular dynamics simulations. Complementary 2H solid-state NMR measurements also show that the lipid acyl chain order parameters are strongly affected by serotonin. The resolution of the puzzle lies in the remarkably different properties displayed by the mixture of these lipids, at molar ratios mimicking those of natural vesicles (PC:PE:PS:Cholesterol = 3:5:2:5). Bilayers constituting of these lipids are minimally perturbed by serotonin, and show only a graded response at physiological concentrations (>100 mM). Significantly, the cholesterol (up to 33% molar ratio) plays only a minor role in dictating these mechanical perturbations, with PC:PE:PS:Cholesterol = 3:5:2:5 and 3:5:2:0 showing similar perturbations. We infer that nature uses an emergent mechanical property of a specific mixture of lipids, all individually vulnerable to serotonin, to appropriately respond to physiological serotonin levels.
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Affiliation(s)
- Ankur Gupta
- Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Pawel Krupa
- Institute of Physics, Polish Academy of Sciences, Warsaw 02-668, Poland
| | - Oskar Engberg
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16/18, 04107, Leipzig, Germany
| | - Magdalena Krupa
- Institute of Computer Science, Polish Academy of Sciences, Warsaw 01-248, Poland
| | - Ankur Chaudhary
- Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Mai Suan Li
- Institute of Physics, Polish Academy of Sciences, Warsaw 02-668, Poland
| | - Daniel Huster
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16/18, 04107, Leipzig, Germany
| | - Sudipta Maiti
- Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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