1
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von Lersner A, Fernandes F, Ozawa PM, Jackson M, Masureel M, Ho H, Lima SM, Vagner T, Sung BH, Wehbe M, Franze K, Pua H, Wilson JT, Irish JM, Weaver AM, Di Vizio D, Zijlstra A. Multiparametric Single-Vesicle Flow Cytometry Resolves Extracellular Vesicle Heterogeneity and Reveals Selective Regulation of Biogenesis and Cargo Distribution. ACS NANO 2024; 18:10464-10484. [PMID: 38578701 PMCID: PMC11025123 DOI: 10.1021/acsnano.3c11561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 03/19/2024] [Accepted: 03/27/2024] [Indexed: 04/07/2024]
Abstract
Mammalian cells release a heterogeneous array of extracellular vesicles (EVs) that contribute to intercellular communication by means of the cargo that they carry. To resolve EV heterogeneity and determine if cargo is partitioned into select EV populations, we developed a method named "EV Fingerprinting" that discerns distinct vesicle populations using dimensional reduction of multiparametric data collected by quantitative single-EV flow cytometry. EV populations were found to be discernible by a combination of membrane order and EV size, both of which were obtained through multiparametric analysis of fluorescent features from the lipophilic dye Di-8-ANEPPS incorporated into the lipid bilayer. Molecular perturbation of EV secretion and biogenesis through respective ablation of the small GTPase Rab27a and overexpression of the EV-associated tetraspanin CD63 revealed distinct and selective alterations in EV populations, as well as cargo distribution. While Rab27a disproportionately affects all small EV populations with high membrane order, the overexpression of CD63 selectively increased the production of one small EV population of intermediate membrane order. Multiplexing experiments subsequently revealed that EV cargos have a distinct, nonrandom distribution with CD63 and CD81 selectively partitioning into smaller vs larger EVs, respectively. These studies not only present a method to probe EV biogenesis but also reveal how the selective partitioning of cargo contributes to EV heterogeneity.
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Affiliation(s)
- Ariana
K. von Lersner
- Program in
Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232, United
States
| | - Fabiane Fernandes
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Institute
of Applied Biosciences and Chemistry, Hogeschool
Arnhem en Nijmegen University of Applied Sciences, Nijmegen 6525 EM, Gelderland, Netherlands
| | - Patricia Midori
Murobushi Ozawa
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department
of Cell and Developmental Biology, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Marques Jackson
- Department
of Research Pathology, Genentech, San Francisco, California 94080, United States
| | - Matthieu Masureel
- Department
of Structural Biology, Genentech, San Francisco, California 94080, United States
| | - Hoangdung Ho
- Department
of Structural Biology, Genentech, San Francisco, California 94080, United States
| | - Sierra M. Lima
- Department
of Cell and Developmental Biology, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Tatyana Vagner
- Department
of Surgery, Cedars-Sinai Medical Center, Los Angeles, California 90048, United States
| | - Bong Hwan Sung
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department
of Cell and Developmental Biology, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Mohamed Wehbe
- Department
of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Kai Franze
- Department
of Research Pathology, Genentech, San Francisco, California 94080, United States
- KNIME
GmbH, Konstanz 78467, Germany
| | - Heather Pua
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - John T. Wilson
- Program in
Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232, United
States
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department
of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jonathan M. Irish
- Program in
Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232, United
States
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Department
of Cell and Developmental Biology, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Alissa M. Weaver
- Program in
Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232, United
States
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department
of Cell and Developmental Biology, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Dolores Di Vizio
- Department
of Surgery, Cedars-Sinai Medical Center, Los Angeles, California 90048, United States
| | - Andries Zijlstra
- Program in
Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232, United
States
- Department
of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- The
Center
for EV Research, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department
of Research Pathology, Genentech, San Francisco, California 94080, United States
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2
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Erazo-Oliveras A, Muñoz-Vega M, Salinas ML, Wang X, Chapkin RS. Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk. FEBS J 2024; 291:1299-1352. [PMID: 36282100 PMCID: PMC10126207 DOI: 10.1111/febs.16665] [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: 06/18/2022] [Revised: 09/09/2022] [Accepted: 10/24/2022] [Indexed: 11/07/2022]
Abstract
Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.
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Affiliation(s)
- Alfredo Erazo-Oliveras
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Mónica Muñoz-Vega
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Michael L. Salinas
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Xiaoli Wang
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Robert S. Chapkin
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
- Center for Environmental Health Research; Texas A&M University; College Station, Texas, 77843; USA
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3
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Kyrychenko A, Ladokhin AS. Fluorescent Probes and Quenchers in Studies of Protein Folding and Protein-Lipid Interactions. CHEM REC 2024; 24:e202300232. [PMID: 37695081 PMCID: PMC11113672 DOI: 10.1002/tcr.202300232] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/20/2023] [Indexed: 09/12/2023]
Abstract
Fluorescence spectroscopy provides numerous methodological tools for structural and functional studies of biological macromolecules and their complexes. All fluorescence-based approaches require either existence of an intrinsic probe or an introduction of an extrinsic one. Moreover, studies of complex systems often require an additional introduction of a specific quencher molecule acting in combination with a fluorophore to provide structural or thermodynamic information. Here, we review the fundamentals and summarize the latest progress in applications of different classes of fluorescent probes and their specific quenchers, aimed at studies of protein folding and protein-membrane interactions. Specifically, we discuss various environment-sensitive dyes, FRET probes, probes for short-distance measurements, and several probe-quencher pairs for studies of membrane penetration of proteins and peptides. The goals of this review are: (a) to familiarize the readership with the general concept that complex biological systems often require both a probe and a quencher to decipher mechanistic details of functioning and (b) to provide example of the immediate applications of the described methods.
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Affiliation(s)
- Alexander Kyrychenko
- Institute of Chemistry and School of Chemistry, V. N. Karazin Kharkiv National University, 4 Svobody sq., Kharkiv, 61022, Ukraine
| | - Alexey S Ladokhin
- Department of Biochemistry and Molecular Biology, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, United States
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4
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Tannoo RM, Richert L, Koschut D, Tomishige N, Treffert SM, Kobayashi T, Mély Y, Orian-Rousseau V. Quantitative live imaging reveals a direct interaction between CD44v6 and MET in membrane domains upon activation with both MET ligands, HGF and internalin B. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184236. [PMID: 37793560 DOI: 10.1016/j.bbamem.2023.184236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 09/24/2023] [Accepted: 09/27/2023] [Indexed: 10/06/2023]
Abstract
Deregulation of the receptor tyrosine kinase MET/hepatocyte growth factor (HGF) pathway results in several pathological processes involved in tumor progression and metastasis. In a different context, MET can serve as an entry point for the bacterium Listeria monocytogenes, when activated by the internalin B (InlB) protein during infection of non-phagocytic cells. We have previously demonstrated that MET requires CD44v6 for its ligand-induced activation. However, the stoichiometry and the steps required for the formation of this complex, are still unknown. In this work, we studied the dynamics of the ligand-induced interaction of CD44v6 with MET at the plasma membrane. Using Förster resonance energy transfer-based fluorescence lifetime imaging microscopy in T-47D cells, we evidenced a direct interaction between MET and CD44v6 promoted by HGF and InlB in live cells. In the absence of MET, fluorescence correlation spectroscopy experiments further showed the dimerization of CD44v6 and the increase of its diffusion induced by HGF and InlB. In the presence of MET, stimulation of the cells by HGF or InlB significantly decreased the diffusion of CD44v6, in line with the formation of a ternary complex of MET with CD44v6 and HGF/InlB. Finally, similarly to HGF/InlB, disruption of liquid-ordered domains (Lo) by methyl-β-cyclodextrin increased CD44v6 mobility suggesting that these factors induce the exit of CD44v6 from the Lo domains. Our data led us to propose a model for MET activation, where CD44v6 dimerizes and diffuses rapidly out of Lo domains to form an oligomeric MET/ligand/CD44v6 complex that is instrumental for MET activation.
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Affiliation(s)
- Ryshtee Mary Tannoo
- Laboratory of Bioimaging and Pathologies (LBP), University of Strasbourg (UNISTRA), France; Institute of Biological and Chemical systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Germany
| | - Ludovic Richert
- Laboratory of Bioimaging and Pathologies (LBP), University of Strasbourg (UNISTRA), France.
| | - David Koschut
- Institute of Biological and Chemical systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Germany; Disease Intervention Technology Lab (DITL), Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Nario Tomishige
- Laboratory of Bioimaging and Pathologies (LBP), University of Strasbourg (UNISTRA), France
| | - Sven Máté Treffert
- Institute of Biological and Chemical systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Germany
| | - Toshihide Kobayashi
- Laboratory of Bioimaging and Pathologies (LBP), University of Strasbourg (UNISTRA), France
| | - Yves Mély
- Laboratory of Bioimaging and Pathologies (LBP), University of Strasbourg (UNISTRA), France.
| | - Véronique Orian-Rousseau
- Institute of Biological and Chemical systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Germany.
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5
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Albright JM, Sydor MJ, Shannahan J, Ferreira CR, Holian A. Imipramine Treatment Alters Sphingomyelin, Cholesterol, and Glycerophospholipid Metabolism in Isolated Macrophage Lysosomes. Biomolecules 2023; 13:1732. [PMID: 38136603 PMCID: PMC10742328 DOI: 10.3390/biom13121732] [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: 10/29/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
Lysosomes are degradative organelles that facilitate the removal and recycling of potentially cytotoxic materials and mediate a variety of other cellular processes, such as nutrient sensing, intracellular signaling, and lipid metabolism. Due to these central roles, lysosome dysfunction can lead to deleterious outcomes, including the accumulation of cytotoxic material, inflammation, and cell death. We previously reported that cationic amphiphilic drugs, such as imipramine, alter pH and lipid metabolism within macrophage lysosomes. Therefore, the ability for imipramine to induce changes to the lipid content of isolated macrophage lysosomes was investigated, focusing on sphingomyelin, cholesterol, and glycerophospholipid metabolism as these lipid classes have important roles in inflammation and disease. The lysosomes were isolated from control and imipramine-treated macrophages using density gradient ultracentrifugation, and mass spectrometry was used to measure the changes in their lipid composition. An unsupervised hierarchical cluster analysis revealed a clear differentiation between the imipramine-treated and control lysosomes. There was a significant overall increase in the abundance of specific lipids mostly composed of cholesterol esters, sphingomyelins, and phosphatidylcholines, while lysophosphatidylcholines and ceramides were overall decreased. These results support the conclusion that imipramine's ability to change the lysosomal pH inhibits multiple pH-sensitive enzymes in macrophage lysosomes.
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Affiliation(s)
- Jacob M. Albright
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences (CEHS), University of Montana, Missoula, MT 59812, USA
| | - Matthew J. Sydor
- Department of Biomedical and Pharmaceutical Sciences, Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Jonathan Shannahan
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA;
| | - Christina R. Ferreira
- Metabolite Profiling Facility, Bindley Bioscience Center, Center for Analytical Instrumentation Development, Purdue University, West Lafayette, IN 47907, USA;
| | - Andrij Holian
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences (CEHS), University of Montana, Missoula, MT 59812, USA
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6
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Singh G, George G, Raja SO, Kandaswamy P, Kumar M, Thutupalli S, Laxman S, Gulyani A. A molecular rotor FLIM probe reveals dynamic coupling between mitochondrial inner membrane fluidity and cellular respiration. Proc Natl Acad Sci U S A 2023; 120:e2213241120. [PMID: 37276406 PMCID: PMC10268597 DOI: 10.1073/pnas.2213241120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 04/13/2023] [Indexed: 06/07/2023] Open
Abstract
The inner mitochondrial membrane (IMM), housing components of the electron transport chain (ETC), is the site for respiration. The ETC relies on mobile carriers; therefore, it has long been argued that the fluidity of the densely packed IMM can potentially influence ETC flux and cell physiology. However, it is unclear if cells temporally modulate IMM fluidity upon metabolic or other stimulation. Using a photostable, red-shifted, cell-permeable molecular-rotor, Mitorotor-1, we present a multiplexed approach for quantitatively mapping IMM fluidity in living cells. This reveals IMM fluidity to be linked to cellular-respiration and responsive to stimuli. Multiple approaches combining in vitro experiments and live-cell fluorescence (FLIM) lifetime imaging microscopy (FLIM) show Mitorotor-1 to robustly report IMM 'microviscosity'/fluidity through changes in molecular free volume. Interestingly, external osmotic stimuli cause controlled swelling/compaction of mitochondria, thereby revealing a graded Mitorotor-1 response to IMM microviscosity. Lateral diffusion measurements of IMM correlate with microviscosity reported via Mitorotor-1 FLIM-lifetime, showing convergence of independent approaches for measuring IMM local-order. Mitorotor-1 FLIM reveals mitochondrial heterogeneity in IMM fluidity; between-and-within cells and across single mitochondrion. Multiplexed FLIM lifetime imaging of Mitorotor-1 and NADH autofluorescence reveals that IMM fluidity positively correlates with respiration, across individual cells. Remarkably, we find that stimulating respiration, through nutrient deprivation or chemically, also leads to increase in IMM fluidity. These data suggest that modulating IMM fluidity supports enhanced respiratory flux. Our study presents a robust method for measuring IMM fluidity and suggests a dynamic regulatory paradigm of modulating IMM local order on changing metabolic demand.
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Affiliation(s)
- Gaurav Singh
- Institute for Stem Cell Science and Regenerative Medicine, 560065Bangalore, India
| | - Geen George
- Institute for Stem Cell Science and Regenerative Medicine, 560065Bangalore, India
| | - Sufi O. Raja
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, 500046Hyderabad, India
| | - Ponnuvel Kandaswamy
- Institute for Stem Cell Science and Regenerative Medicine, 560065Bangalore, India
| | - Manoj Kumar
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences, Tata Institute of Fundamental Research, 560065Bangalore, India
| | - Shashi Thutupalli
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences, Tata Institute of Fundamental Research, 560065Bangalore, India
- International Centre for Theoretical Sciences, Tata Institute for Fundamental Research, 560089 Bangalore, India
| | - Sunil Laxman
- Institute for Stem Cell Science and Regenerative Medicine, 560065Bangalore, India
| | - Akash Gulyani
- Institute for Stem Cell Science and Regenerative Medicine, 560065Bangalore, India
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, 500046Hyderabad, India
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7
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Murate M, Yokoyama N, Tomishige N, Richert L, Humbert N, Pollet B, Makino A, Kono N, Mauri L, Aoki J, Sako Y, Sonnino S, Komura N, Ando H, Kaneko MK, Kato Y, Inamori KI, Inokuchi JI, Mély Y, Iwabuchi K, Kobayashi T. Cell density-dependent membrane distribution of ganglioside GM3 in melanoma cells. Cell Mol Life Sci 2023; 80:167. [PMID: 37249637 PMCID: PMC11073213 DOI: 10.1007/s00018-023-04813-9] [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: 01/20/2023] [Revised: 04/21/2023] [Accepted: 05/17/2023] [Indexed: 05/31/2023]
Abstract
Monosialoganglioside GM3 is the simplest ganglioside involved in various cellular signaling. Cell surface distribution of GM3 is thought to be crucial for the function of GM3, but little is known about the cell surface GM3 distribution. It was shown that anti-GM3 monoclonal antibody binds to GM3 in sparse but not in confluent melanoma cells. Our model membrane study evidenced that monoclonal anti-GM3 antibodies showed stronger binding when GM3 was in less fluid membrane environment. Studies using fluorescent GM3 analogs suggested that GM3 was clustered in less fluid membrane. Moreover, fluorescent lifetime measurement showed that cell surface of high density melanoma cells is more fluid than that of low density cells. Lipidomics and fatty acid supplementation experiment suggested that monounsaturated fatty acid-containing phosphatidylcholine contributed to the cell density-dependent membrane fluidity. Our results indicate that anti-GM3 antibody senses GM3 clustering and the number and/or size of GM3 cluster differ between sparse and confluent melanoma cells.
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Affiliation(s)
- Motohide Murate
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan.
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan.
| | - Noriko Yokoyama
- Institute for Environmental and Gender-Specific Medicine, Graduate School of Medicine, Juntendo University, Urayasu, Chiba, 279-0021, Japan
| | - Nario Tomishige
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Ludovic Richert
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Nicolas Humbert
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Brigitte Pollet
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Asami Makino
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
- Molecular Physiology Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Laura Mauri
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan
| | - Sandro Sonnino
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Naoko Komura
- Institute for Glyco-Core Research, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Hiromune Ando
- Institute for Glyco-Core Research, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Kei-Ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, 981-8558, Japan
| | - Jin-Ichi Inokuchi
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, 981-8558, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, Toyonaka, Osaka, 560-0043, Japan
| | - Yves Mély
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France
| | - Kazuhisa Iwabuchi
- Institute for Environmental and Gender-Specific Medicine, Graduate School of Medicine, Juntendo University, Urayasu, Chiba, 279-0021, Japan.
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan.
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401, Illkirch, France.
- Cellular Informatics Laboratory, RIKEN CPR, Wako, Saitama, 351-0198, Japan.
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8
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Xia Q, Wan W, Jin W, Huang Y, Sun R, Wang M, Jing B, Peng C, Dong X, Zhang R, Gao Z, Liu Y. Solvatochromic Cellular Stress Sensors Reveal the Compactness Heterogeneity and Dynamics of Aggregated Proteome. ACS Sens 2022; 7:1919-1925. [PMID: 35776067 DOI: 10.1021/acssensors.2c00566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Deterioration of protein homeostasis (proteostasis) often induces aberrant proteome aggregation. Visualization and dissection of the stressed proteome are of particular interest given their association with numerous degenerative diseases. Recent progress in chemical cellular stress sensors allows for direct visualization of aggregated proteome. Beyond its localization and morphology, the physicochemical nature and the dynamics of the aggregated proteome have been challenging to explore. Herein, we developed a series of solvatochromic fluorene-based D-π-A probes that can selectively and noncovalently bind to a misfolded and aggregated proteome and report on their compactness heterogeneity upon cellular stresses. We achieved this goal by variation of the heterocyclic acceptors to modulate their solvatochromism and binding affinity to amorphous aggregated proteins. The optimized sensor P6 was capable of sensing the polarity differences among different aggregated proteins via its fluorescence emission wavelength. In live cells, P6 revealed the cellular compactness heterogeneity in the aggregated proteome upon cellular stresses. Given the combinative solvatochromic and noncovalent properties, our probe can reversibly monitor the dynamic changes in the aggregated proteome compactness upon stress and after stress recovery, suggesting its potential applications in search of therapeutics to counteract disease-causing proteome stresses.
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Affiliation(s)
- Qiuxuan Xia
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.,University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Wang Wan
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Wenhan Jin
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Yanan Huang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Rui Sun
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.,University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Mengdie Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.,University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Biao Jing
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.,The Second Hospital of Dalian Medical University, 467 Zhongshan Road, Dalian, 116023, China
| | - Congcong Peng
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.,The Second Hospital of Dalian Medical University, 467 Zhongshan Road, Dalian, 116023, China
| | - Xuepeng Dong
- The Second Hospital of Dalian Medical University, 467 Zhongshan Road, Dalian, 116023, China
| | - Rixin Zhang
- The Second Hospital of Dalian Medical University, 467 Zhongshan Road, Dalian, 116023, China
| | - Zhenming Gao
- The Second Hospital of Dalian Medical University, 467 Zhongshan Road, Dalian, 116023, China
| | - Yu Liu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
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9
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Biocompatible and optically stable hydrophobic fluorescent carbon dots for isolation and imaging of lipid rafts in model membrane. Anal Bioanal Chem 2022; 414:6055-6067. [PMID: 35697813 DOI: 10.1007/s00216-022-04165-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/06/2022] [Accepted: 06/02/2022] [Indexed: 11/01/2022]
Abstract
Lateral heterogeneity in cell membranes features a variety of compositions that influence their inherent properties. One such biophysical variation is the formation of a membrane or lipid raft, which plays important roles in many cellular processes. The lipid rafts on the cell membrane are mostly identified by specific dyes and heavy metal quantum dots, which have their own drawbacks, such as cytotoxicity, photostability, and incompatibility. To this end, we synthesized special, hydrophobic, fluorescent, photostable, and non-cytotoxic carbon dots (CDs) by solvent-free thermal treatment using non-cytotoxic materials and incorporated into the lipid bilayers of giant unilamellar vesicles (GUVs) made from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) lipids. A 2:2:1 mixture of DOPC, DPPC, and cholesterol (Chol) develops lipid rafts on the membrane by phase separation. The photophysical properties of the CDs get modulated on incorporation into the lipid rafts that identifies the membrane heterogeneity. The main attempt in this work is to develop a new, simple, cost-effective, and bio-friendly lipid raft marker, which can be used in biological applications, alongside other conventional raft markers, with more advantages.
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10
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A near-infrared plasma membrane-specific AIE probe for fluorescence lifetime imaging of phagocytosis. Sci China Chem 2022. [DOI: 10.1007/s11426-021-1199-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractPhagocytosis is a biological process that plays a key role in host defense and tissue homeostasis. Efficient approaches for realtime imaging of phagocytosis are highly desired but limited. Herein, an AIE-active near-infrared fluorescent probe, named TBTCP, was developed for fluorescence lifetime imaging of phagocytosis. TBTCP could selectively label the cell plasma membrane with fast staining, wash-free process, high signal-to-background ratio, and excellent photostability. Cellular membrane statuses under different osmolarities as well as macrophage phagocytosis of bacteria or large silica particles in early stages could be reported by the fluorescence lifetime changes of TBTCP. Compared with current fluorescence imaging methods, which target the bioenvironmental changes in the late phagocytosis stage, this approach detects the changes in the cell membrane, thus giving a faster response to phagocytosis. This article provides a functional tool to report the phagocytic dynamics of macrophages which may greatly contribute to the studies of phagocytic function-related diseases.
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11
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Need for more focus on lipid species in studies of biological and model membranes. Prog Lipid Res 2022; 86:101160. [DOI: 10.1016/j.plipres.2022.101160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 03/06/2022] [Indexed: 11/23/2022]
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12
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Plant Sterol Clustering Correlates with Membrane Microdomains as Revealed by Optical and Computational Microscopy. MEMBRANES 2021; 11:membranes11100747. [PMID: 34677513 PMCID: PMC8539253 DOI: 10.3390/membranes11100747] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/22/2021] [Accepted: 09/27/2021] [Indexed: 11/26/2022]
Abstract
Local inhomogeneities in lipid composition play a crucial role in the regulation of signal transduction and membrane traffic. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids. Nevertheless, most evidence for microdomains in cells remains indirect, and the nature of membrane inhomogeneities has been difficult to characterize. We used a new push–pull pyrene probe and fluorescence lifetime imaging microscopy (FLIM) combined with all-atom multiscale molecular dynamics simulations to provide a detailed view on the interaction between phospholipids and phytosterol and the effect of modulating cellular phytosterols on membrane-associated microdomains and phase separation formation. Our understanding of the organization principles of biomembranes is limited mainly by the challenge to measure distributions and interactions of lipids and proteins within the complex environment of living cells. Comparing phospholipids/phytosterol compositions typical of liquid-disordered (Ld) and liquid-ordered (Lo) domains, we furthermore show that phytosterols play crucial roles in membrane homeostasis. The simulation work highlights how state-of-the-art modeling alleviates some of the prior concerns and how unrefuted discoveries can be made through a computational microscope. Altogether, our results support the role of phytosterols in the lateral structuring of the PM of plant cells and suggest that they are key compounds for the formation of plant PM microdomains and the lipid-ordered phase.
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13
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Bouarab L, Degraeve P, Bouajila J, Cottaz A, Jbilou F, Joly C, Oulahal N. Staphylococcus aureus membrane-damaging activities of four phenolics. FEMS Microbiol Lett 2021; 368:6309896. [PMID: 34173656 DOI: 10.1093/femsle/fnab081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 06/24/2021] [Indexed: 11/13/2022] Open
Abstract
The membrane-damaging activities of four phenolics chosen for their bactericidal activity against Staphylococcus aureus CNRZ3 were investigated: 5,7-dihydroxy-4-phenylcoumarin (DHPC), 5,8-dihydroxy-1,4-naphthoquinone (DHNQ), epigallocatechin gallate (EGCG) and isobutyl 4-hydroxybenzoate (IBHB). Staphylococcus aureus CNRZ3 cells, as well as model liposomes mimicking its membrane phospholipids composition, were treated with each phenolic at its minimal bactericidal concentration. Membrane integrity, intracellular pH and intracellular esterase activity were examined by flow cytometric analysis of S. aureus cells stained with propidium iodide and SYTO® 9, 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl ester, and 5(6)-carboxyfluorescein diacetate, respectively. While intracellular pH was affected by the foyr phenolics, only DHNQ and to a lesser extent EGCG, caused a loss of membrane integrity. Flow cytometric analysis of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and DPPC/POPG (2-oleoyl-1-palmitoyl-sn-glycero-3-phosphoglycerol) liposomes stained with Coumarin 6 (which penetrates the lipid bilayer) or 5-N(octadecanoyl)-amino-fluorescein (which binds to the liposome shell) suggested that only EGCG and DHNQ penetrated the bilayer of phospholipids of liposomes. Taken together, these findings support the hypothesis that EGCG and DHNQ bactericidal activity results from their accumulation in the phospholipid bilayer of S. aureus cells membrane causing its disruption.
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Affiliation(s)
- Lynda Bouarab
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
| | - Pascal Degraeve
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
| | - Jalloul Bouajila
- Laboratoire de Génie Chimique, UMR 5503, Université de Toulouse, CNRS, INPT, UPS, F-31062 Toulouse, France
| | - Amandine Cottaz
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
| | - Fouzia Jbilou
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
| | - Catherine Joly
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
| | - Nadia Oulahal
- Univ Lyon, Université Claude Bernard Lyon 1, ISARA Lyon, BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires), Equipe Mixte d'Accueil n°3733, IUT Lyon 1, technopole Alimentec, rue Henri de Boissieu, F-01000 Bourg en Bresse, France
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14
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Junqueira H, Schroder AP, Thalmann F, Klymchenko A, Mély Y, Baptista MS, Marques CM. Molecular organization in hydroperoxidized POPC bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183659. [PMID: 34052197 DOI: 10.1016/j.bbamem.2021.183659] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 04/23/2021] [Accepted: 05/24/2021] [Indexed: 11/30/2022]
Abstract
Lipid hydroperoxides are the primary reaction products of lipid oxidation, a natural outcome of life under oxygen. While playing a major role in cell metabolism, the microscopic origins of the effects of lipid hydroperoxidation on biomembranes remain elusive. Here we probe the polar structure of partially to fully hydroperoxidized bilayers of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) by a combination of environment-sensitive fluorescent probes and coarse-grained Martini numerical simulations. We find that the inserted organic hydroperoxide group -OOH migrates preferentially to the surface for bilayers with small fractions of hydroperoxidized lipids, but populates also significantly the bilayer interior for larger fractions. Our findings suggest that by modifying the intimate polarity of biomembranes, lipid peroxidation will have a significant impact on the activity of transmembrane proteins and on the bio-medical efficiency of membrane active molecules such as cell-penetrating and antimicrobial peptides.
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Affiliation(s)
- Helena Junqueira
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo, CP 66318, 05314970 São Paulo, Brazil
| | - André P Schroder
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, F-67000 Strasbourg, France.
| | - Fabrice Thalmann
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, F-67000 Strasbourg, France
| | - Andrey Klymchenko
- Université de Strasbourg, Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de pharmacie, 74 route du Rhin, CS 60024, 67401 Illkirch Cedex, France
| | - Yves Mély
- Université de Strasbourg, Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de pharmacie, 74 route du Rhin, CS 60024, 67401 Illkirch Cedex, France
| | - Mauricio S Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, Brazil
| | - Carlos M Marques
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, F-67000 Strasbourg, France
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15
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Sydor MJ, Anderson DS, Steele HBB, Ross JBA, Holian A. Fluorescence lifetime imaging microscopy and time-resolved anisotropy of nanomaterial-induced changes to red blood cell membranes. Methods Appl Fluoresc 2021; 9. [PMID: 33973872 DOI: 10.1088/2050-6120/abf424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/31/2021] [Indexed: 11/11/2022]
Abstract
With the use of engineered nano-materials (ENM) becoming more prevalent, it is essential to determine potential human health impacts. Specifically, the effects on biological lipid membranes will be important for determining molecular events that may contribute to both toxicity and suitable biomedical applications. To better understand the mechanisms of ENM-induced hemolysis and membrane permeability, fluorescence lifetime imaging microscopy (FLIM) was performed on human red blood cells (RBC) exposed to titanium dioxide ENM, zinc oxide ENM, or micron-sized crystalline silica. In the FLIM images, changes in the intensity-weighted fluorescence lifetime of the lipophilic fluorescence probe Di-4-ANEPPDHQ were used to identify localized changes to membrane. Time-resolved fluorescence anisotropy and FLIM of RBC treated with methyl-ß-cyclodextrin was performed to aid in interpreting how changes to membrane order influence changes in the fluorescence lifetime of the probe. Treatment of RBC with methyl-ß-cyclodextrin caused an increase in the wobble-in-a-cone angle and shorter fluorescence lifetimes of di-4-ANEPPDHQ. Treatment of RBC with titanium dioxide caused a significant increase in fluorescence lifetime compared to non-treated samples, indicating increased membrane order. Crystalline silica also increased the fluorescence lifetime compared to control levels. In contrast, zinc oxide decreased the fluorescence lifetime, representing decreased membrane order. However, treatment with soluble zinc sulfate resulted in no significant change in fluorescence lifetime, indicating that the decrease in order of the RBC membranes caused by zinc oxide ENM was not due to zinc ions formed during potential dissolution of the nanoparticles. These results give insight into mechanisms for how these three materials might disrupt RBC membranes and membranes of other cells. The results also provide evidence for a direct correlation between the size, interaction-available surface area of the nano-material and cell membrane disruption.
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Affiliation(s)
- Matthew J Sydor
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, United States of America
| | - Donald S Anderson
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, United States of America
| | - Harmen B B Steele
- Department of Chemistry and Biochemistry, University of Montana, Missoula, United States of America.,Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, United States of America
| | - J B Alexander Ross
- Department of Chemistry and Biochemistry, University of Montana, Missoula, United States of America.,Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, United States of America
| | - Andrij Holian
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, United States of America
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16
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Sych T, Gurdap CO, Wedemann L, Sezgin E. How Does Liquid-Liquid Phase Separation in Model Membranes Reflect Cell Membrane Heterogeneity? MEMBRANES 2021; 11:323. [PMID: 33925240 PMCID: PMC8146956 DOI: 10.3390/membranes11050323] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/22/2022]
Abstract
Although liquid-liquid phase separation of cytoplasmic or nuclear components in cells has been a major focus in cell biology, it is only recently that the principle of phase separation has been a long-standing concept and extensively studied in biomembranes. Membrane phase separation has been reconstituted in simplified model systems, and its detailed physicochemical principles, including essential phase diagrams, have been extensively explored. These model membrane systems have proven very useful to study the heterogeneity in cellular membranes, however, concerns have been raised about how reliably they can represent native membranes. In this review, we will discuss how phase-separated membrane systems can mimic cellular membranes and where they fail to reflect the native cell membrane heterogeneity. We also include a few humble suggestions on which phase-separated systems should be used for certain applications, and which interpretations should be avoided to prevent unreliable conclusions.
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Affiliation(s)
| | | | | | - Erdinc Sezgin
- Science for Life Laboratory, Department of Women’s and Children’s Health, Karolinska Institutet, 17165 Solna, Sweden; (T.S.); (C.O.G.); (L.W.)
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17
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Zakyrjanova GF, Giniatullin AR, Mukhutdinova KA, Kuznetsova EA, Petrov AM. Early differences in membrane properties at the neuromuscular junctions of ALS model mice: Effects of 25-hydroxycholesterol. Life Sci 2021; 273:119300. [PMID: 33662433 DOI: 10.1016/j.lfs.2021.119300] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/13/2021] [Accepted: 02/25/2021] [Indexed: 12/11/2022]
Abstract
AIMS Plasma hyperlipidemia is a protective factor in amyotrophic lateral sclerosis (ALS) while cholesterol-lowering drugs aggravate the pathology. We hypothesize that this phenomenon can be linked with membrane lipid alterations in the neuromuscular junctions (NMJs) occurring before motor neuron loss. METHODS Neurotransmitter release in parallel with lipid membrane properties in diaphragm NMJs of SOD1G93A (mSOD) mice at nine weeks of age (pre-onset stage) were assessed. KEY FINDINGS Despite on slight changes in spontaneous and evoked quantum release of acetylcholine, extracellular levels of choline at resting conditions, an indicator of non-quantum release, were significantly increased in mSOD mice. The use of lipid-sensitive fluorescent probes points to lipid raft disruption in the NMJs of mSOD mice. However, content of cholesterol, a key raft component was unchanged implying another pathway responsible for the loss of raft integrity. In the mSOD mice we found marked increase in levels of raft-destabilizing lipid ceramide. This was accompanied by enhanced ability to uptake of exogenous ceramide in NMJs. Acute and chronic administration of 25-hydroxycholesterol, whose levels increase due to hypercholesterolemia, recovered early alterations in membrane properties. Furthermore, chronic treatment with 25-hydroxycholesterol prevented increase in ceramide and extracellular choline levels as well as suppressed lipid peroxidation of NMJ membranes and fragmentation of end plates. SIGNIFICANCE Thus, lipid raft disruption likely due to ceramide accumulation could be early event in ALS which may trigger neuromuscular abnormalities. Cholesterol derivative 25-hydroxycholesterol may serve as a molecule restoring the membrane and functional properties of NMJs at the early stage.
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Affiliation(s)
- Guzel F Zakyrjanova
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan, 420012, Russia
| | - Arthur R Giniatullin
- Department of Normal Physiology, Kazan State Medial University, 49 Butlerova Street, Kazan 420012, Russia
| | - Kamilla A Mukhutdinova
- Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan, 420012, Russia
| | - Eva A Kuznetsova
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia
| | - Alexey M Petrov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan, 420012, Russia.
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18
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Glazier R, Shinde P, Ogasawara H, Salaita K. Spectroscopic Analysis of a Library of DNA Tension Probes for Mapping Cellular Forces at Fluid Interfaces. ACS APPLIED MATERIALS & INTERFACES 2021; 13:2145-2164. [PMID: 33417432 DOI: 10.1021/acsami.0c09774] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Oligonucleotide-based probes offer the highest spatial resolution, force sensitivity, and molecular specificity for cellular tension sensing and have been developed to measure a variety of molecular forces mediated by individual receptors in T cells, platelets, fibroblasts, B-cells, and immortalized cancer cell lines. These fluorophore-oligonucleotide conjugate probes are designed with a stem-loop structure that engages cell receptors and reversibly unfolds due to mechanical strain. With the growth of recent work bridging molecular mechanobiology and biomaterials, there is a need for a detailed spectroscopic analysis of DNA tension probes that are used for cellular imaging. In this manuscript, we conducted an analysis of 19 DNA hairpin-based tension probe variants using molecular dynamics simulations, absorption spectroscopy, and fluorescence imaging (epifluorescence and fluorescence lifetime imaging microscopy). We find that tension probes are highly sensitive to their molecular design, including donor and acceptor proximity and pairing, DNA stem-loop structure, and conjugation chemistry. We demonstrate the impact of these design features using a supported lipid bilayer model of podosome-like adhesions. Finally, we discuss the requirements for tension imaging in various biophysical contexts and offer a series of experimental recommendations, thus providing a guide for the design and application of DNA hairpin-based molecular tension probes.
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Affiliation(s)
- Roxanne Glazier
- Wallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, Atlanta, Georgia 30322, United States
| | - Pushkar Shinde
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Hiroaki Ogasawara
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Khalid Salaita
- Wallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, Atlanta, Georgia 30322, United States
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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19
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Soteriou C, Kalli AC, Connell SD, Tyler AII, Thorne JL. Advances in understanding and in multi-disciplinary methodology used to assess lipid regulation of signalling cascades from the cancer cell plasma membrane. Prog Lipid Res 2020; 81:101080. [PMID: 33359620 DOI: 10.1016/j.plipres.2020.101080] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 12/31/2022]
Abstract
The lipid bilayer is a functional component of cells, forming a stable platform for the initiation of key biological processes, including cell signalling. There are distinct changes in the lipid composition of cell membranes during oncogenic transformation resulting in aberrant activation and inactivation of signalling transduction pathways. Studying the role of the cell membrane in cell signalling is challenging, since techniques are often limited to by timescale, resolution, sensitivity, and averaging. To overcome these limitations, combining 'computational', 'wet-lab' and 'semi-dry' approaches offers the best opportunity to resolving complex biological processes involved in membrane organisation. In this review, we highlight analytical tools that have been applied for the study of cell signalling initiation from the cancer cell membranes through computational microscopy, biological assays, and membrane biophysics. The cancer therapeutic potential of extracellular membrane-modulating agents, such as cholesterol-reducing agents is also discussed, as is the need for future collaborative inter-disciplinary research for studying the role of the cell membrane and its components in cancer therapy.
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Affiliation(s)
- C Soteriou
- School of Food Science and Nutrition, University of Leeds, Leeds LS29JT, UK; Leeds Institute of Cardiovascular and Metabolic Medicine and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK; Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - A C Kalli
- Leeds Institute of Cardiovascular and Metabolic Medicine and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - S D Connell
- Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - A I I Tyler
- School of Food Science and Nutrition, University of Leeds, Leeds LS29JT, UK
| | - J L Thorne
- School of Food Science and Nutrition, University of Leeds, Leeds LS29JT, UK.
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20
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Páez-Pérez M, López-Duarte I, Vyšniauskas A, Brooks NJ, Kuimova MK. Imaging non-classical mechanical responses of lipid membranes using molecular rotors. Chem Sci 2020; 12:2604-2613. [PMID: 34164028 PMCID: PMC8179291 DOI: 10.1039/d0sc05874b] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lipid packing in cellular membranes has a direct effect on membrane tension and microviscosity, and plays a central role in cellular adaptation, homeostasis and disease. According to conventional mechanical descriptions, viscosity and tension are directly interconnected, with increased tension leading to decreased membrane microviscosity. However, the intricate molecular interactions that combine to build the structure and function of a cell membrane suggest a more complex relationship between these parameters. In this work, a viscosity-sensitive fluorophore (‘molecular rotor’) is used to map changes in microviscosity in model membranes under conditions of osmotic stress. Our results suggest that the relationship between membrane tension and microviscosity is strongly influenced by the bilayer's lipid composition. In particular, we show that the effects of increasing tension are minimised for membranes that exhibit liquid disordered (Ld) – liquid ordered (Lo) phase coexistence; while, surprisingly, membranes in pure gel and Lo phases exhibit a negative compressibility behaviour, i.e. they soften upon compression. Viscosity-sensitive molecular rotors demonstrate that the non-classical mechanical behaviour of model lipid membranes is able to buffer external stress.![]()
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Affiliation(s)
- Miguel Páez-Pérez
- MSRH, Department of Chemistry, Imperial College London Wood Lane London W12 0BZ UK
| | - Ismael López-Duarte
- MSRH, Department of Chemistry, Imperial College London Wood Lane London W12 0BZ UK .,Departamento de Química Orgánica, Universidad Autónoma de Madrid Cantoblanco 28049 Madrid Spain
| | - Aurimas Vyšniauskas
- MSRH, Department of Chemistry, Imperial College London Wood Lane London W12 0BZ UK .,Center of Physical Sciences and Technology Saulėtekio av. 3 Vilnius Lithuania
| | - Nicholas J Brooks
- MSRH, Department of Chemistry, Imperial College London Wood Lane London W12 0BZ UK
| | - Marina K Kuimova
- MSRH, Department of Chemistry, Imperial College London Wood Lane London W12 0BZ UK
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21
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PTEN activation contributes to neuronal and synaptic engulfment by microglia in tauopathy. Acta Neuropathol 2020; 140:7-24. [PMID: 32236736 PMCID: PMC7300099 DOI: 10.1007/s00401-020-02151-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022]
Abstract
Phosphatase and tensin homolog (PTEN) regulates synaptic density in development; however, whether PTEN also regulates synapse loss in a neurodegenerative disorder such as frontotemporal lobar degeneration with Tau deposition (FTLD-Tau) has not been explored. Here, we found that pathological Tau promotes early activation of PTEN, which precedes apoptotic caspase-3 cleavage in the rTg4510 mouse model of FTLD-Tau. We further demonstrate increased synaptic and neuronal exposure of the apoptotic signal phosphatidylserine that tags neuronal structures for microglial uptake, thereby linking PTEN activation to synaptic and neuronal structure elimination. By applying pharmacological inhibition of PTEN's protein phosphatase activity, we observed that microglial uptake can be decreased in Tau transgenic mice. Finally, we reveal a dichotomous relationship between PTEN activation and age in FTLD-Tau patients and healthy controls. Together, our findings suggest that in tauopathy, PTEN has a role in the synaptotoxicity of pathological Tau and promotes microglial removal of affected neuronal structures.
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22
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Khmelinskaia A, Marquês JMT, Bastos AEP, Antunes CAC, Bento-Oliveira A, Scolari S, Lobo GMDS, Malhó R, Herrmann A, Marinho HS, de Almeida RFM. Liquid-Ordered Phase Formation by Mammalian and Yeast Sterols: A Common Feature With Organizational Differences. Front Cell Dev Biol 2020; 8:337. [PMID: 32596234 PMCID: PMC7304482 DOI: 10.3389/fcell.2020.00337] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/17/2020] [Indexed: 11/13/2022] Open
Abstract
Here, biophysical properties of membranes enriched in three metabolically related sterols are analyzed both in vitro and in vivo. Unlike cholesterol and ergosterol, the common metabolic precursor zymosterol is unable to induce the formation of a liquid ordered (l o) phase in model lipid membranes and can easily accommodate in a gel phase. As a result, Zym has a marginal ability to modulate the passive membrane permeability of lipid vesicles with different compositions, contrary to cholesterol and ergosterol. Using fluorescence-lifetime imaging microscopy of an aminostyryl dye in living mammalian and yeast cells we established a close parallel between sterol-dependent membrane biophysical properties in vivo and in vitro. This approach unraveled fundamental differences in yeast and mammalian plasma membrane organization. It is often suggested that, in eukaryotes, areas that are sterol-enriched are also rich in sphingolipids, constituting highly ordered membrane regions. Our results support that while cholesterol is able to interact with saturated lipids, ergosterol seems to interact preferentially with monounsaturated phosphatidylcholines. Taken together, we show that different eukaryotic kingdoms developed unique solutions for the formation of a sterol-rich plasma membrane, a common evolutionary trait that accounts for sterol structural diversity.
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Affiliation(s)
- Alena Khmelinskaia
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Joaquim M T Marquês
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - André E P Bastos
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Catarina A C Antunes
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Andreia Bento-Oliveira
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Silvia Scolari
- Department of Biology, Molecular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Gerson M da S Lobo
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rui Malhó
- Faculdade de Ciências, BioISI, Universidade de Lisboa, Lisbon, Portugal
| | - Andreas Herrmann
- Department of Biology, Molecular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
| | - H Susana Marinho
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rodrigo F M de Almeida
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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23
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Sydor MJ, Anderson DS, Steele HBB, Ross JBA, Holian A. Effects of titanium dioxide and zinc oxide nano-materials on lipid order in model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183313. [PMID: 32304756 DOI: 10.1016/j.bbamem.2020.183313] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/08/2020] [Accepted: 04/13/2020] [Indexed: 12/14/2022]
Abstract
Engineered nano-materials (ENM) have been reported to affect lipid membrane permeability in cell models, but a mechanistic understanding of how these materials interact with biological membranes has not been described. To assess mechanisms of permeability, liposomes composed of DOPC, DOPS, or POPC, with or without cholesterol, were used as model membranes for measuring ENM-induced changes to lipid order to improve our understanding of ENM effects on membrane permeability. Liposomes were treated with either titanium dioxide (TiO2) or zinc oxide (ZnO) ENM, and changes to lipid order were measured by time-resolved fluorescence anisotropy of a lipophilic probe, Di-4-ANEPPDHQ. Both ENM increased lipid order in two lipid models differing in headgroup charge. TiO2 increased lipid order of POPC liposomes (neutral charge), while ZnO acted primarily on DOPS liposomes (negative charge). Addition of cholesterol to these models significantly increased lipid order while in some cases attenuated ENM-induced changes to lipid order. To assess the ability of ENM to induce membrane permeability, liposomes composed of the above lipids were assayed for membrane permeability by calcein leakage in response to ENM. Both ENM caused a dose-dependent increase in permeability in all liposome models tested, and the addition of cholesterol to the liposome models neither blocked nor reduced calcein leakage. Together, these experiments show that ENM increased permeability of small molecules (calcein) from model liposomes, and that the magnitude of the effect of ENM on lipid order depended on ENM surface charge, lipid head group charge and the presence of cholesterol in the membrane.
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Affiliation(s)
- Matthew J Sydor
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States of America.
| | - Donald S Anderson
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States of America.
| | - Harmen B B Steele
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, United States of America; Center for Biomolecular and Structure & Dynamics, University of Montana, Missoula, MT 59812, United States of America.
| | - J B Alexander Ross
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, United States of America; Center for Biomolecular and Structure & Dynamics, University of Montana, Missoula, MT 59812, United States of America.
| | - Andrij Holian
- Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States of America.
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24
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Levental I, Levental KR, Heberle FA. Lipid Rafts: Controversies Resolved, Mysteries Remain. Trends Cell Biol 2020; 30:341-353. [PMID: 32302547 DOI: 10.1016/j.tcb.2020.01.009] [Citation(s) in RCA: 290] [Impact Index Per Article: 72.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 01/08/2023]
Abstract
The lipid raft hypothesis postulates that lipid-lipid interactions can laterally organize biological membranes into domains of distinct structures, compositions, and functions. This proposal has in equal measure exhilarated and frustrated membrane research for decades. While the physicochemical principles underlying lipid-driven domains has been explored and is well understood, the existence and relevance of such domains in cells remains elusive, despite decades of research. Here, we review the conceptual underpinnings of the raft hypothesis and critically discuss the supporting and contradicting evidence in cells, focusing on why controversies about the composition, properties, and even the very existence of lipid rafts remain unresolved. Finally, we highlight several recent breakthroughs that may resolve existing controversies and suggest general approaches for moving beyond questions of the existence of rafts and towards understanding their physiological significance.
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Affiliation(s)
- Ilya Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX 70030, USA.
| | - Kandice R Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX 70030, USA
| | - Frederick A Heberle
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA; Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN 33830, USA
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25
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Coomer CA, Carlon-Andres I, Iliopoulou M, Dustin ML, Compeer EB, Compton AA, Padilla-Parra S. Single-cell glycolytic activity regulates membrane tension and HIV-1 fusion. PLoS Pathog 2020; 16:e1008359. [PMID: 32084246 PMCID: PMC7055913 DOI: 10.1371/journal.ppat.1008359] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 03/04/2020] [Accepted: 01/27/2020] [Indexed: 12/21/2022] Open
Abstract
There has been resurgence in determining the role of host metabolism in viral infection yet deciphering how the metabolic state of single cells affects viral entry and fusion remains unknown. Here, we have developed a novel assay multiplexing genetically-encoded biosensors with single virus tracking (SVT) to evaluate the influence of global metabolic processes on the success rate of virus entry in single cells. We found that cells with a lower ATP:ADP ratio prior to virus addition were less permissive to virus fusion and infection. These results indicated a relationship between host metabolic state and the likelihood for virus-cell fusion to occur. SVT revealed that HIV-1 virions were arrested at hemifusion in glycolytically-inactive cells. Interestingly, cells acutely treated with glycolysis inhibitor 2-deoxyglucose (2-DG) become resistant to virus infection and also display less surface membrane cholesterol. Addition of cholesterol in these in glycolytically-inactive cells rescued the virus entry block at hemifusion and enabled completion of HIV-1 fusion. Further investigation with FRET-based membrane tension and membrane order reporters revealed a link between host cell glycolytic activity and host membrane order and tension. Indeed, cells treated with 2-DG possessed lower plasma membrane lipid order and higher tension values, respectively. Our novel imaging approach that combines lifetime imaging (FLIM) and SVT revealed not only changes in plasma membrane tension at the point of viral fusion, but also that HIV is less likely to enter cells at areas of higher membrane tension. We therefore have identified a connection between host cell glycolytic activity and membrane tension that influences HIV-1 fusion in real-time at the single-virus fusion level in live cells.
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Affiliation(s)
- Charles A. Coomer
- Cellular Imaging Group, Wellcome Centre Human Genetics, University of Oxford, Oxford, United Kingdom
- HIV Dynamics and Replication Program, National Cancer Institute, Frederick, Maryland, United States of America
- University of Kentucky, College of Medicine, Lexington, Kentucky, United States of America
- Division of Structural Biology, Wellcome Centre Human Genetics, University of Oxford, United Kingdom
| | - Irene Carlon-Andres
- Cellular Imaging Group, Wellcome Centre Human Genetics, University of Oxford, Oxford, United Kingdom
- Division of Structural Biology, Wellcome Centre Human Genetics, University of Oxford, United Kingdom
| | - Maro Iliopoulou
- Cellular Imaging Group, Wellcome Centre Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Michael L. Dustin
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
| | - Ewoud B. Compeer
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
| | - Alex A. Compton
- HIV Dynamics and Replication Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - Sergi Padilla-Parra
- Cellular Imaging Group, Wellcome Centre Human Genetics, University of Oxford, Oxford, United Kingdom
- Division of Structural Biology, Wellcome Centre Human Genetics, University of Oxford, United Kingdom
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26
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Regan D, Williams J, Borri P, Langbein W. Lipid Bilayer Thickness Measured by Quantitative DIC Reveals Phase Transitions and Effects of Substrate Hydrophilicity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:13805-13814. [PMID: 31483674 PMCID: PMC7007255 DOI: 10.1021/acs.langmuir.9b02538] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 08/13/2019] [Indexed: 05/22/2023]
Abstract
Quantitative differential interference contrast microscopy is demonstrated here as a label-free method, which is able to image and measure the thickness of lipid bilayers with 0.1 nm precision. We investigate the influence of the substrate on the thickness of fluid-phase 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)-supported lipid bilayers and find a thinning of up to 10%, depending on substrate hydrophilicity, local bilayer coverage, and ionic strength of the medium. With fluorescently labeled lipid bilayers, we also observe changes in the bilayer thickness depending on the choice of fluorophore. Furthermore, liquid-ordered domains in bilayers, formed from DOPC, cholesterol, and sphingomyelin, are measured, and the corresponding thickness change between the liquid-ordered and liquid-disordered phases is accurately determined. Again, the thickness difference is found to be dependent on the presence of the fluorophore label, highlighting the need for quantitative label-free techniques.
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Affiliation(s)
- David Regan
- School
of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, U.K.
- E-mail: (D.R.)
| | - Joseph Williams
- School
of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K.
| | - Paola Borri
- School
of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K.
| | - Wolfgang Langbein
- School
of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, U.K.
- E-mail: (W.L.)
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27
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Steele HBB, Sydor MJ, Anderson DS, Holian A, Ross JBA. Using Time-Resolved Fluorescence Anisotropy of di-4-ANEPPDHQ and F2N12S to Analyze Lipid Packing Dynamics in Model Systems. J Fluoresc 2019; 29:347-352. [PMID: 30937610 DOI: 10.1007/s10895-019-02363-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/10/2019] [Indexed: 11/29/2022]
Abstract
The fluorescence probes di-4-ANEPPDHQ and F2N12S have solvochromatic emission spectra and fluorescence lifetimes that are sensitive to order within the environment of lipid membranes. We show in this communication that the time-resolved fluorescence anisotropy of these probes, analyzed either by the wobble-in-a-cone model or by the model-independent order parameter S2, provides complementary information about dynamics and lipid packing in a variety of homogeneous lipid membranes systems.
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Affiliation(s)
- Harmen B B Steele
- Department of Chemistry & Biochemistry, University of Montana, Missoula, MT, 59812, USA.,Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, MT, 59812, USA
| | - Matthew J Sydor
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Donald S Anderson
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Andrij Holian
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, 59812, USA
| | - J B Alexander Ross
- Department of Chemistry & Biochemistry, University of Montana, Missoula, MT, 59812, USA. .,Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, MT, 59812, USA.
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28
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Mondal D, Dutta R, Banerjee P, Mukherjee D, Maiti TK, Sarkar N. Modulation of Membrane Fluidity Performed on Model Phospholipid Membrane and Live Cell Membrane: Revealing through Spatiotemporal Approaches of FLIM, FAIM, and TRFS. Anal Chem 2019; 91:4337-4345. [PMID: 30821145 DOI: 10.1021/acs.analchem.8b04044] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have elucidated the role of unsaturated fatty acid in the in vitro model phospholipid membrane and in vivo live cell membrane. Fluorescence microscopy and time-resolved fluorescence spectroscopy have been employed to uncover how modulation of vesicle bilayer fluidity persuades structural transformation. This unsaturation induced structural transformation due to packing disorder in bilayer has been delineated through spatially resolved fluorescence lifetime imaging microscopy (FLIM) and fluorescence polarization or anisotropy imaging microscopy (FPIM/FAIM). Structure-function relationship of phospholipid vesicle is also investigated by monitoring intervesicular water dynamics behavior, which has been demonstrated by temporally resolved fluorescence spectroscopy (TRFS) techniques. Nevertheless, it has also been manifested from this study that loss of rigidity in bilayer breaks down the strong hydrogen bond (H-bond) network around the charged lipid head groups. The disruption of this H-bond network increases the bilayer elasticity, which helps to evolve various kinds of vesicular structure. Furthermore, the significant influence of unsaturated fatty acid on membrane bilayer has been ratified through in vivo live cell imaging.
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Affiliation(s)
- Dipankar Mondal
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Rupam Dutta
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Pavel Banerjee
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Devdeep Mukherjee
- Department of Biotechnology , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Tapas Kumar Maiti
- Department of Biotechnology , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Nilmoni Sarkar
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
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29
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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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30
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Gulyani A, Dey N, Bhattacharya S. Highly Responsive Fluorescent Assemblies Allow for Unique, Multiparametric Sensing of the Phospholipid Membrane Environment. Chemistry 2018; 25:1507-1514. [DOI: 10.1002/chem.201803627] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Indexed: 01/24/2023]
Affiliation(s)
- Akash Gulyani
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
- Institute for Stem Cell Biology & Regenerative Medicine; GKVK Post, Bangalore 560065 India
| | - Nilanjan Dey
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
- Institute for Stem Cell Biology & Regenerative Medicine; GKVK Post, Bangalore 560065 India
| | - Santanu Bhattacharya
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
- Present address: Indian Association for Cultivation of Science; Kolkata 700032 India
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31
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Wijesooriya CS, Nyamekye CKA, Smith EA. Optical Imaging of the Nanoscale Structure and Dynamics of Biological Membranes. Anal Chem 2018; 91:425-440. [DOI: 10.1021/acs.analchem.8b04755] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
| | - Charles K. A. Nyamekye
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- The Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011, United States
| | - Emily A. Smith
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- The Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011, United States
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32
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Sholokh M, Sharma R, Grytsyk N, Zaghzi L, Postupalenko VY, Dziuba D, Barthes NPF, Michel BY, Boudier C, Zaporozhets OA, Tor Y, Burger A, Mély Y. Environmentally Sensitive Fluorescent Nucleoside Analogues for Surveying Dynamic Interconversions of Nucleic Acid Structures. Chemistry 2018; 24:13850-13861. [PMID: 29989220 DOI: 10.1002/chem.201802297] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Indexed: 11/12/2022]
Abstract
Nucleic acids are characterized by a variety of dynamically interconverting structures that play a major role in transcriptional and translational regulation as well as recombination and repair. To monitor these interconversions, Förster resonance energy transfer (FRET)-based techniques can be used, but require two fluorophores that are typically large and can alter the DNA/RNA structure and protein binding. Additionally, events that do not alter the donor/acceptor distance and/or angular relationship are frequently left undetected. A more benign approach relies on fluorescent nucleobases that can substitute their native counterparts with minimal perturbation, such as the recently developed 2-thienyl-3-hydroxychromone (3HCnt) and thienoguanosine (th G). To demonstrate the potency of 3HCnt and th G in deciphering interconversion mechanisms, we used the conversion of the (-)DNA copy of the HIV-1 primer binding site (-)PBS stem-loop into (+)/(-)PBS duplex, as a model system. When incorporated into the (-)PBS loop, the two probes were found to be highly sensitive to the individual steps both in the absence and the presence of a nucleic acid chaperone, providing the first complete mechanistic description of this critical process in HIV-1 replication. The combination of the two distinct probes appears to be instrumental for characterizing structural transitions of nucleic acids under various stimuli.
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Affiliation(s)
- Marianna Sholokh
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France.,Department of Chemistry, Kyiv National Taras Shevchenko University, 60 Volodymyrska street, 01033, Kyiv, Ukraine
| | - Rajhans Sharma
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
| | - Natalia Grytsyk
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
| | - Lyes Zaghzi
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
| | - Viktoriia Y Postupalenko
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
| | - Dmytro Dziuba
- Institut de Chimie de Nice, UMR 7272 CNRS, Université Côte d'Azur, Parc Valrose, 06108, Nice, France
| | - Nicolas P F Barthes
- Institut de Chimie de Nice, UMR 7272 CNRS, Université Côte d'Azur, Parc Valrose, 06108, Nice, France
| | - Benoît Y Michel
- Institut de Chimie de Nice, UMR 7272 CNRS, Université Côte d'Azur, Parc Valrose, 06108, Nice, France
| | - Christian Boudier
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
| | - Olga A Zaporozhets
- Department of Chemistry, Kyiv National Taras Shevchenko University, 60 Volodymyrska street, 01033, Kyiv, Ukraine
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0358, USA
| | - Alain Burger
- Institut de Chimie de Nice, UMR 7272 CNRS, Université Côte d'Azur, Parc Valrose, 06108, Nice, France
| | - Yves Mély
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, Faculté de Pharmacie, 74 Route du Rhin, 67401, Illkirch, France
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33
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Humeniuk HV, Rosspeintner A, Licari G, Kilin V, Bonacina L, Vauthey E, Sakai N, Matile S. White‐Fluorescent Dual‐Emission Mechanosensitive Membrane Probes that Function by Bending Rather than Twisting. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804662] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
| | | | - Giuseppe Licari
- Department of Physical ChemistryUniversity of Geneva Geneva Switzerland
| | - Vasyl Kilin
- Department of Applied PhysicsUniversity of Geneva Geneva Switzerland
| | - Luigi Bonacina
- Department of Applied PhysicsUniversity of Geneva Geneva Switzerland
| | - Eric Vauthey
- Department of Physical ChemistryUniversity of Geneva Geneva Switzerland
| | - Naomi Sakai
- Department of Organic ChemistryUniversity of Geneva Geneva Switzerland
| | - Stefan Matile
- Department of Organic ChemistryUniversity of Geneva Geneva Switzerland
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34
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Humeniuk HV, Rosspeintner A, Licari G, Kilin V, Bonacina L, Vauthey E, Sakai N, Matile S. White-Fluorescent Dual-Emission Mechanosensitive Membrane Probes that Function by Bending Rather than Twisting. Angew Chem Int Ed Engl 2018; 57:10559-10563. [PMID: 29924457 PMCID: PMC6099517 DOI: 10.1002/anie.201804662] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Indexed: 12/20/2022]
Abstract
Bent N,N'-diphenyl-dihydrodibenzo[a,c]phenazine amphiphiles are introduced as mechanosensitive membrane probes that operate by an unprecedented mechanism, namely, unbending in the excited state as opposed to the previously reported untwisting in the ground and twisting in the excited state. Their dual emission from bent or "closed" and planarized or "open" excited states is shown to discriminate between micelles in water and monomers in solid-ordered (So ), liquid-disordered (Ld ) and bulk membranes. The dual-emission spectra cover enough of the visible range to produce vesicles that emit white light with ratiometrically encoded information. Strategies to improve the bent mechanophores with expanded π systems and auxochromes are reported, and compatibility with imaging of membrane domains in giant unilamellar vesicles by two-photon excitation fluorescence (TPEF) microscopy is demonstrated.
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Affiliation(s)
| | | | - Giuseppe Licari
- Department of Physical ChemistryUniversity of GenevaGenevaSwitzerland
| | - Vasyl Kilin
- Department of Applied PhysicsUniversity of GenevaGenevaSwitzerland
| | - Luigi Bonacina
- Department of Applied PhysicsUniversity of GenevaGenevaSwitzerland
| | - Eric Vauthey
- Department of Physical ChemistryUniversity of GenevaGenevaSwitzerland
| | - Naomi Sakai
- Department of Organic ChemistryUniversity of GenevaGenevaSwitzerland
| | - Stefan Matile
- Department of Organic ChemistryUniversity of GenevaGenevaSwitzerland
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35
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Laguerre A, Schultz C. Novel lipid tools and probes for biological investigations. Curr Opin Cell Biol 2018; 53:97-104. [PMID: 30015291 DOI: 10.1016/j.ceb.2018.06.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/12/2018] [Accepted: 06/29/2018] [Indexed: 12/21/2022]
Abstract
We present the latest advances in lipid tool development for studying cellular membrane trafficking and metabolism. We focus on chemical modifications that are introduced to natural lipid structures. The new functionalities are used to follow and interfere with lipid dynamics in intact cells.
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Affiliation(s)
- Aurélien Laguerre
- Dept. of Physiology & Pharmacology, Oregon Health and Science University (OHSU), Portland, OR, USA
| | - Carsten Schultz
- Dept. of Physiology & Pharmacology, Oregon Health and Science University (OHSU), Portland, OR, USA; European Molecular Biology Laboratory (EMBL), Cell Biology and Biophysics Unit, 69117 Heidelberg, Germany.
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36
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Shaya J, Collot M, Bénailly F, Mahmoud N, Mély Y, Michel BY, Klymchenko AS, Burger A. Turn-on Fluorene Push-Pull Probes with High Brightness and Photostability for Visualizing Lipid Order in Biomembranes. ACS Chem Biol 2017; 12:3022-3030. [PMID: 29053920 DOI: 10.1021/acschembio.7b00658] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The rational design of environmentally sensitive dyes with superior properties is critical for elucidating the fundamental biological processes and understanding the biophysical behavior of cell membranes. In this study, a novel group of fluorene-based push-pull probes was developed for imaging membrane lipids. The design of these fluorogenic conjugates is based on a propioloyl linker to preserve the required spectroscopic features of the core dye. This versatile linker allowed the introduction of a polar deoxyribosyl head, a lipophilic chain, and an amphiphilic/anchoring group to tune the cell membrane binding and internalization. It was found that the deoxyribosyl head favored cell internalization and staining of intracellular membranes, whereas an amphiphilic anchor group ensured specific plasma membrane staining. The optimized fluorene probes presented a set of improvements as compared to commonly used environmentally sensitive membrane probe Laurdan such as red-shifted absorption matching the 405 nm diode laser excitation, a blue-green emission range complementary to the red fluorescent proteins, enhanced brightness and photostability, as well as preserved sensitivity to lipid order, as shown in model membranes and living cells.
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Affiliation(s)
- Janah Shaya
- Université Côte d’Azur, CNRS, Institut de Chimie de Nice, UMR 7272 − Parc Valrose, 06108 Nice cedex 2, France
| | - Mayeul Collot
- Laboratoire
de Biophotonique et Pharmacologie, UMR 7213, Faculté de Pharmacie, Université de Strasbourg, CNRS, 74 Route du Rhin, 67401 Illkirch, France
| | - Frédéric Bénailly
- Université Côte d’Azur, CNRS, Institut de Chimie de Nice, UMR 7272 − Parc Valrose, 06108 Nice cedex 2, France
| | - Najiba Mahmoud
- Université Côte d’Azur, CNRS, Institut de Chimie de Nice, UMR 7272 − Parc Valrose, 06108 Nice cedex 2, France
| | - Yves Mély
- Laboratoire
de Biophotonique et Pharmacologie, UMR 7213, Faculté de Pharmacie, Université de Strasbourg, CNRS, 74 Route du Rhin, 67401 Illkirch, France
| | - Benoît Y. Michel
- Université Côte d’Azur, CNRS, Institut de Chimie de Nice, UMR 7272 − Parc Valrose, 06108 Nice cedex 2, France
| | - Andrey S. Klymchenko
- Laboratoire
de Biophotonique et Pharmacologie, UMR 7213, Faculté de Pharmacie, Université de Strasbourg, CNRS, 74 Route du Rhin, 67401 Illkirch, France
| | - Alain Burger
- Université Côte d’Azur, CNRS, Institut de Chimie de Nice, UMR 7272 − Parc Valrose, 06108 Nice cedex 2, France
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37
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Pyrshev KA, Yesylevskyy SO, Mély Y, Demchenko AP, Klymchenko AS. Caspase-3 activation decreases lipid order in the outer plasma membrane leaflet during apoptosis: A fluorescent probe study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2123-2132. [PMID: 28784460 DOI: 10.1016/j.bbamem.2017.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 07/12/2017] [Accepted: 08/03/2017] [Indexed: 12/23/2022]
Abstract
In this research we investigate the connection between the cytoplasmic machinery of apoptosis and the plasma membrane organization by studying the coupling of caspase-3 activation and inhibition with PS exposure and the change of lipid order in plasma membrane sensed by a fluorescent membrane probe NR12S. First, we performed in silico molecular dynamics simulations, which suggest that the mechanism of response of NR12S to lipid order may combine both sensitivity to membrane polarity/hydration and change in the fluorophore orientation. Second, cellular studies revealed that upon triggering apoptosis with IPA-3 and camptothecin the NR12S response is similar to that observed after decrease of lipid order induced by cholesterol depletion, 7-ketocholesterol enrichment or sphingomyelin hydrolysis. NR12S response can be influenced by a caspase-3 inhibitor Z-DEVD-FMK. Flow cytometry data further indicate that the NR12S response correlates with the response of FITC-labeled DEVD-FMK peptide and GFP-labeled Annexin V on the whole time scale (0-24h) of apoptosis induction by camptothecin. We conclude that fine changes in lipid order observed by NR12S are coupled with early steps of cellular events in apoptosis.
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Affiliation(s)
- Kyrylo A Pyrshev
- Laboratoire de Biophotonique et Pharmacologie UMR 7213 CNRS/Université de Strasbourg, Illkirch, France; Laboratory of Nanobiotechnologies, Department of Molecular Immunology, O.V. Palladin Institute of Biochemistry of NASU, Kyiv 01601, Ukraine.
| | - Semen O Yesylevskyy
- Department of Physics of Biological Systems, Institute of Physics of NASU, Kyiv 03680, Ukraine
| | - Yves Mély
- Laboratoire de Biophotonique et Pharmacologie UMR 7213 CNRS/Université de Strasbourg, Illkirch, France
| | - Alexander P Demchenko
- Laboratory of Nanobiotechnologies, Department of Molecular Immunology, O.V. Palladin Institute of Biochemistry of NASU, Kyiv 01601, Ukraine
| | - Andrey S Klymchenko
- Laboratoire de Biophotonique et Pharmacologie UMR 7213 CNRS/Université de Strasbourg, Illkirch, France
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38
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Mazeres S, Fereidouni F, Joly E. Using spectral decomposition of the signals from laurdan-derived probes to evaluate the physical state of membranes in live cells. F1000Res 2017; 6:763. [PMID: 28663788 PMCID: PMC5473435 DOI: 10.12688/f1000research.11577.2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/28/2017] [Indexed: 01/22/2023] Open
Abstract
Background: We wanted to investigate the physical state of biological membranes in live cells under the most physiological conditions possible. Methods: For this we have been using laurdan, C-laurdan or M-laurdan to label a variety of cells, and a biphoton microscope equipped with both a thermostatic chamber and a spectral analyser. We also used a flow cytometer to quantify the 450/530 nm ratio of fluorescence emissions by whole cells. Results: We find that using all the information provided by spectral analysis to perform spectral decomposition dramatically improves the imaging resolution compared to using just two channels, as commonly used to calculate generalized polarisation (GP). Coupled to a new plugin called Fraction Mapper, developed to represent the fraction of light intensity in the first component in a stack of two images, we obtain very clear pictures of both the intra-cellular distribution of the probes, and the polarity of the cellular environments where the lipid probes are localised. Our results lead us to conclude that, in live cells kept at 37°C, laurdan, and M-laurdan to a lesser extent, have a strong tendency to accumulate in the very apolar environment of intra-cytoplasmic lipid droplets, but label the plasma membrane (PM) of mammalian cells ineffectively. On the other hand, C-laurdan labels the PM very quickly and effectively, and does not detectably accumulate in lipid droplets. Conclusions: From using these probes on a variety of mammalian cell lines, as well as on cells from
Drosophila and
Dictyostelium discoideum, we conclude that, apart from the lipid droplets, which are very apolar, probes in intracellular membranes reveal a relatively polar and hydrated environment, suggesting a very marked dominance of liquid disordered states. PMs, on the other hand, are much more apolar, suggesting a strong dominance of liquid ordered state, which fits with their high sterol contents.
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Affiliation(s)
- Serge Mazeres
- Membrane and DNA Dynamics Team, Institut de Pharmacologie et de Biologie Structurale, CNRS, Université de Toulouse, Toulouse, F-31077, France
| | - Farzad Fereidouni
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, CA 95817, CA, 4400, USA
| | - Etienne Joly
- Membrane and DNA Dynamics Team, Institut de Pharmacologie et de Biologie Structurale, CNRS, Université de Toulouse, Toulouse, F-31077, France
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39
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Mazeres S, Fereidouni F, Joly E. Using spectral decomposition of the signals from laurdan-derived probes to evaluate the physical state of membranes in live cells. F1000Res 2017; 6:763. [PMID: 28663788 DOI: 10.12688/f1000research.11577.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/26/2017] [Indexed: 12/13/2022] Open
Abstract
Background: We wanted to investigate the physical state of biological membranes in live cells under the most physiological conditions possible. Methods: For this we have been using laurdan, C-laurdan or M-laurdan to label a variety of cells, and a biphoton microscope equipped with both a thermostatic chamber and a spectral analyser. We also used a flow cytometer to quantify the 450/530 nm ratio of fluorescence emissions by whole cells. Results: We find that using all the information provided by spectral analysis to perform spectral decomposition dramatically improves the imaging resolution compared to using just two channels, as commonly used to calculate generalized polarisation (GP). Coupled to a new plugin called Fraction Mapper, developed to represent the fraction of light intensity in the first component in a stack of two images, we obtain very clear pictures of both the intra-cellular distribution of the probes, and the polarity of the cellular environments where the lipid probes are localised. Our results lead us to conclude that, in live cells kept at 37°C, laurdan, and M-laurdan to a lesser extent, have a strong tendency to accumulate in the very apolar environment of intra-cytoplasmic lipid droplets, but label the plasma membrane (PM) of mammalian cells ineffectively. On the other hand, C-laurdan labels the PM very quickly and effectively, and does not detectably accumulate in lipid droplets. Conclusions: From using these probes on a variety of mammalian cell lines, as well as on cells from Drosophila and Dictyostelium discoideum, we conclude that, apart from the lipid droplets, which are very apolar, probes in intracellular membranes reveal a relatively polar and hydrated environment, suggesting a very marked dominance of liquid disordered states. PMs, on the other hand, are much more apolar, suggesting a strong dominance of liquid ordered state, which fits with their high sterol contents.
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Affiliation(s)
- Serge Mazeres
- Membrane and DNA Dynamics Team, Institut de Pharmacologie et de Biologie Structurale, CNRS, Université de Toulouse, Toulouse, F-31077, France
| | - Farzad Fereidouni
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, CA 95817, CA, 4400, USA
| | - Etienne Joly
- Membrane and DNA Dynamics Team, Institut de Pharmacologie et de Biologie Structurale, CNRS, Université de Toulouse, Toulouse, F-31077, France
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40
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Kilin V, Gavvala K, Barthes NPF, Michel BY, Shin D, Boudier C, Mauffret O, Yashchuk V, Mousli M, Ruff M, Granger F, Eiler S, Bronner C, Tor Y, Burger A, Mély Y. Dynamics of Methylated Cytosine Flipping by UHRF1. J Am Chem Soc 2017; 139:2520-2528. [PMID: 28112929 PMCID: PMC5335914 DOI: 10.1021/jacs.7b00154] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
DNA methylation patterns, which are critical for gene expression, are replicated by DNA methyltransferase 1 (DNMT1) and ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) proteins. This replication is initiated by the recognition of hemimethylated CpG sites and further flipping of methylated cytosines (mC) by the Set and Ring Associated (SRA) domain of UHRF1. Although crystallography has shed light on the mechanism of mC flipping by SRA, tools are required to monitor in real time how SRA reads DNA and flips the modified nucleobase. To accomplish this aim, we have utilized two distinct fluorescent nucleobase surrogates, 2-thienyl-3-hydroxychromone nucleoside (3HCnt) and thienoguanosine (thG), incorporated at different positions into hemimethylated (HM) and nonmethylated (NM) DNA duplexes. Large fluorescence changes were associated with mC flipping in HM duplexes, showing the outstanding sensitivity of both nucleobase surrogates to the small structural changes accompanying base flipping. Importantly, the nucleobase surrogates marginally affected the structure of the duplex and its affinity for SRA at positions where they were responsive to base flipping, illustrating their promise as nonperturbing probes for monitoring such events. Stopped-flow studies using these two distinct tools revealed the fast kinetics of SRA binding and sliding to NM duplexes, consistent with its reader role. In contrast, the kinetics of mC flipping was found to be much slower in HM duplexes, substantially increasing the lifetime of CpG-bound UHRF1, and thus the probability of recruiting DNMT1 to faithfully duplicate the DNA methylation profile. The fluorescence-based approach using these two different fluorescent nucleoside surrogates advances the mechanistic understanding of the UHRF1/DNMT1 tandem and the development of assays for the identification of base flipping inhibitors.
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Affiliation(s)
- Vasyl Kilin
- Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Universitéde Strasbourg, Facultéde pharmacie, 74 Route du Rhin, 67401 Illkirch, France
| | - Krishna Gavvala
- Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Universitéde Strasbourg, Facultéde pharmacie, 74 Route du Rhin, 67401 Illkirch, France
| | - Nicolas P. F. Barthes
- Institut de Chimie de Nice, UMR 7272 CNRS, UniversitéCôte d’Azur, Parc Valrose, 06108 Nice Cedex 2, France
| | - Benoît Y. Michel
- Institut de Chimie de Nice, UMR 7272 CNRS, UniversitéCôte d’Azur, Parc Valrose, 06108 Nice Cedex 2, France
| | - Dongwon Shin
- TriLink BioTechnologies, LLC., San Diego, California 92121, United States
| | - Christian Boudier
- Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Universitéde Strasbourg, Facultéde pharmacie, 74 Route du Rhin, 67401 Illkirch, France
| | - Olivier Mauffret
- LBPA, UMR 8113 CNRS, ENS Paris-Saclay, Université Paris Saclay, 94235 Cachan Cedex, France
| | - Valeriy Yashchuk
- Department of Physics, Kiev National Taras Shevchenko University, Kiev 01601, Ukraine
| | - Marc Mousli
- Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Universitéde Strasbourg, Facultéde pharmacie, 74 Route du Rhin, 67401 Illkirch, France
| | - Marc Ruff
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964 CNRS UMR 7104, Université de Strasbourg, Illkirch 67000, France
| | - Florence Granger
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964 CNRS UMR 7104, Université de Strasbourg, Illkirch 67000, France
| | - Sylvia Eiler
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964 CNRS UMR 7104, Université de Strasbourg, Illkirch 67000, France
| | - Christian Bronner
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964 CNRS UMR 7104, Université de Strasbourg, Illkirch 67000, France
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Alain Burger
- Institut de Chimie de Nice, UMR 7272 CNRS, UniversitéCôte d’Azur, Parc Valrose, 06108 Nice Cedex 2, France
| | - Yves Mély
- Laboratoire de Biophotonique et Pharmacologie, UMR 7213 CNRS, Universitéde Strasbourg, Facultéde pharmacie, 74 Route du Rhin, 67401 Illkirch, France
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41
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Szakács Z, Kállay M, Kubinyi M. Theoretical study on the photooxygenation and photorearrangement reactions of 3-hydroxyflavone. RSC Adv 2017. [DOI: 10.1039/c7ra04590e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The mechanisms of three photodegradation reactions of 3-hydroxyflavone – its photosensitized oxygenation, photooxygenation with 3O2 and photorearrangement into an indanedione derivative – have been investigated by computing the free energy profiles.
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Affiliation(s)
- Zoltán Szakács
- Department of Physical Chemistry and Materials Science
- Budapest University of Technology and Economics
- 1521 Budapest
- Hungary
| | - Mihály Kállay
- MTA-BME Lendület Quantum Chemistry Research Group
- Department of Physical Chemistry and Materials Science
- Budapest University of Technology and Economics
- 1521 Budapest
- Hungary
| | - Miklós Kubinyi
- Department of Physical Chemistry and Materials Science
- Budapest University of Technology and Economics
- 1521 Budapest
- Hungary
- Institute of Materials and Environmental Chemistry
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42
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Houston JE, Kraft M, Mooney I, Terry AE, Scherf U, Evans RC. Charge-Mediated Localization of Conjugated Polythiophenes in Zwitterionic Model Cell Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:8141-8153. [PMID: 27434827 DOI: 10.1021/acs.langmuir.6b01828] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The selective engineering of conjugated polyelectrolyte (CPE)-phospholipid interfaces is poised to play a key role in the design of advanced biomedical and biotechnological devices. Herein, we report a strategic study to investigate the relationship between the charge of the CPE side group and their association with zwitterionic phospholipid bilayers. The interaction of dipalmitoylphosphatidylcholine (DPPC) phospholipid vesicles with a series of poly(thiophene)s bearing zwitterionic, cationic, or anionic terminal groups (P3Zwit, P3TMAHT and P3Anionic, respectively) has been probed. Although all CPEs showed an affinity for the zwitterionic vesicles, the calculated partition coefficients determined using photoluminescence spectroscopy suggested preferential incorporation within the lipid bilayer in the order P3Zwit > P3Anionic ≫ P3TMAHT. The polarity probe Prodan was used to further qualify the position of the CPE inside the vesicle bilayers via Förster resonance energy transfer (FRET) studies. The varying proximity of the CPEs to Prodan was reflected in the Stern-Volmer quenching constants and decreased in the order P3Anionic > P3TMAHT ≫ P3Zwit. Dynamic light scattering measurements showed an increase in the hydrodynamic diameter of the DPPC vesicles upon addition of each poly(thiophene), but to the greatest extent for P3Anionic. Small-angle neutron scattering studies also revealed that P3Anionic specifically increased the thickness of the headgroup region of the phospholipid bilayer. Epifluorescence and atomic force microscopy imaging showed that P3TMAHT formed amorphous agglomerates on the vesicle surface, P3Zwit was buried throughout the bilayer, and P3Anionic formed a shell of protruding chains around the surface, which promoted vesicle fusion. The global data indicate three distinctive modes of interaction for the poly(thiophene)s within DPPC vesicles, whereby the nature of the association is ultimately controlled by the pendant charge group on each CPE chain. Our results suggest that charge-mediated self-assembly may provide a simple and effective route to design luminescent CPE probes capable of specific localization within phospholipid membranes.
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Affiliation(s)
- Judith E Houston
- School of Chemistry and CRANN, University of Dublin, Trinity College , College Green, Dublin 2, Ireland
| | - Mario Kraft
- Macromolecular Chemistry Group (Buwmakro) and Institute for Polymer Technology, Bergische Universität Wuppertal , Gauss-Str. 20, D-42119 Wuppertal, Germany
| | - Ian Mooney
- School of Chemistry and CRANN, University of Dublin, Trinity College , College Green, Dublin 2, Ireland
| | - Ann E Terry
- ISIS, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, U.K
| | - Ullrich Scherf
- Macromolecular Chemistry Group (Buwmakro) and Institute for Polymer Technology, Bergische Universität Wuppertal , Gauss-Str. 20, D-42119 Wuppertal, Germany
| | - Rachel C Evans
- School of Chemistry and CRANN, University of Dublin, Trinity College , College Green, Dublin 2, Ireland
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43
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Gavvala K, Barthes NPF, Bonhomme D, Dabert-Gay AS, Debayle D, Michel BY, Burger A, Mély Y. A turn-on dual emissive nucleobase sensitive to mismatches and duplex conformational changes. RSC Adv 2016. [DOI: 10.1039/c6ra19061h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Herein, we demonstrate the on–off dual emissive behaviour of a fluorescent nucleoside sensitive towards DNA hybridization and conformational changes as well as detection of single nucleotide polymorphisms.
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Affiliation(s)
- Krishna Gavvala
- Laboratoire de Biophotonique et Pharmacologie
- UMR 7213
- Faculté de Pharmacie
- Université de Strasbourg
- CNRS
| | - Nicolas P. F. Barthes
- Institut de Chimie de Nice
- UMR 7272
- Université de Nice Sophia Antipolis
- CNRS
- Parc Valrose
| | - Dominique Bonhomme
- Institut de Chimie de Nice
- UMR 7272
- Université de Nice Sophia Antipolis
- CNRS
- Parc Valrose
| | - Anne Sophie Dabert-Gay
- Institut de Pharmacologie Moléculaire et Cellulaire
- UMR 6097
- Université de Nice Sophia Antipolis
- 660 Route des Lucioles
- 06560 Valbonne
| | - Delphine Debayle
- Institut de Pharmacologie Moléculaire et Cellulaire
- UMR 6097
- Université de Nice Sophia Antipolis
- 660 Route des Lucioles
- 06560 Valbonne
| | - Benoît Y. Michel
- Institut de Chimie de Nice
- UMR 7272
- Université de Nice Sophia Antipolis
- CNRS
- Parc Valrose
| | - Alain Burger
- Institut de Chimie de Nice
- UMR 7272
- Université de Nice Sophia Antipolis
- CNRS
- Parc Valrose
| | - Yves Mély
- Laboratoire de Biophotonique et Pharmacologie
- UMR 7213
- Faculté de Pharmacie
- Université de Strasbourg
- CNRS
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44
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Dent MR, López-Duarte I, Dickson CJ, Chairatana P, Anderson HL, Gould IR, Wylie D, Vyšniauskas A, Brooks NJ, Kuimova MK. Imaging plasma membrane phase behaviour in live cells using a thiophene-based molecular rotor. Chem Commun (Camb) 2016; 52:13269-13272. [DOI: 10.1039/c6cc05954f] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A thiophene-based molecular rotor was used to probe ordering and viscosity within artificial lipid bilayers and live cell plasma membranes.
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Affiliation(s)
| | - Ismael López-Duarte
- Department of Chemistry
- Imperial College London
- London
- UK
- Department of Chemistry
| | - Callum J. Dickson
- Computer-Aided Drug Discovery
- Global Discovery Chemistry
- Novartis Institutes for BioMedical Research
- Cambridge
- USA
| | - Phoom Chairatana
- Department of Chemistry
- Chemistry Research Laboratory
- Oxford University
- Oxford
- UK
| | - Harry L. Anderson
- Department of Chemistry
- Chemistry Research Laboratory
- Oxford University
- Oxford
- UK
| | - Ian R. Gould
- Department of Chemistry
- Imperial College London
- London
- UK
| | - Douglas Wylie
- Department of Chemistry
- Imperial College London
- London
- UK
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45
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Soleimanpour S, Colom A, Derivery E, Gonzalez-Gaitan M, Roux A, Sakai N, Matile S. Headgroup engineering in mechanosensitive membrane probes. Chem Commun (Camb) 2016; 52:14450-14453. [DOI: 10.1039/c6cc08771j] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Tricky chemistry had to be addressed to make mechanosensitive membrane probes ready for use, including a chalcogen-bond mediated “molecular guillotinylation”.
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Affiliation(s)
- Saeideh Soleimanpour
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Adai Colom
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Emmanuel Derivery
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Marcos Gonzalez-Gaitan
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Aurelien Roux
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Naomi Sakai
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
| | - Stefan Matile
- NCCR Chemical Biology
- School of Chemistry and Biochemistry
- University of Geneva
- Geneva
- Switzerland
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46
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Houston JE, Kraft M, Scherf U, Evans RC. Sequential detection of multiple phase transitions in model biological membranes using a red-emitting conjugated polyelectrolyte. Phys Chem Chem Phys 2016; 18:12423-7. [DOI: 10.1039/c6cp01553k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Charge-mediated assembly of an anionic poly(thiophene) leads to a highly sensitive probe of membrane order.
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Affiliation(s)
- Judith E. Houston
- School of Chemistry
- University of Dublin
- Trinity College
- Dublin 2
- Ireland
| | - Mario Kraft
- Macromolecular Chemistry Group (buwmacro) and Institute for Polymer Technology
- Bergische Universität Wuppertal
- Wuppertal
- Germany
| | - Ullrich Scherf
- Macromolecular Chemistry Group (buwmacro) and Institute for Polymer Technology
- Bergische Universität Wuppertal
- Wuppertal
- Germany
| | - Rachel C. Evans
- School of Chemistry
- University of Dublin
- Trinity College
- Dublin 2
- Ireland
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Kyrychenko A. Using fluorescence for studies of biological membranes: a review. Methods Appl Fluoresc 2015; 3:042003. [DOI: 10.1088/2050-6120/3/4/042003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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