1
|
Pérez-Mitta G, Sezgin Y, Wang W, MacKinnon R. Freestanding bilayer microscope for single-molecule imaging of membrane proteins. SCIENCE ADVANCES 2024; 10:eado4722. [PMID: 38905330 PMCID: PMC11192074 DOI: 10.1126/sciadv.ado4722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/16/2024] [Indexed: 06/23/2024]
Abstract
Integral membrane proteins (IMPs) constitute a large fraction of organismal proteomes, playing fundamental roles in physiology and disease. Despite their importance, the mechanisms underlying dynamic features of IMPs, such as anomalous diffusion, protein-protein interactions, and protein clustering, remain largely unknown due to the high complexity of cell membrane environments. Available methods for in vitro studies are insufficient to study IMP dynamics systematically. This publication introduces the freestanding bilayer microscope (FBM), which combines the advantages of freestanding bilayers with single-particle tracking. The FBM, based on planar lipid bilayers, enables the study of IMP dynamics with single-molecule resolution and unconstrained diffusion. This paper benchmarks the FBM against total internal reflection fluorescence imaging on supported bilayers and is used here to estimate ion channel open probability and to examine the diffusion behavior of an ion channel in phase-separated bilayers. The FBM emerges as a powerful tool to examine membrane protein/lipid organization and dynamics to understand cell membrane processes.
Collapse
Affiliation(s)
- Gonzalo Pérez-Mitta
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Yeliz Sezgin
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | | | - Roderick MacKinnon
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| |
Collapse
|
2
|
Liu Y, Cui S, Ma W, Wu Y, Xin R, Bai Y, Chen Z, Xu J, Ge J. Direct Imaging of Protein Clusters in Metal-Organic Frameworks. J Am Chem Soc 2024; 146:12565-12576. [PMID: 38661569 DOI: 10.1021/jacs.4c01483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Protein@metal-organic frameworks (P@MOFs) prepared by coprecipitation of protein, metal ions, and organic ligands represent an effective method for protein stabilization with a wide spectrum of applications. However, the formation mechanism of P@MOFs via the coprecipitation process and the reason why proteins can retain their biological activity in the frameworks with highly concentrated metal ions remain unsettled. Here, by a combined methodology of single molecule localization microscopy and clustering analysis, we discovered that in this process enzyme molecules form clusters with metal ions and organic ligands, contributing to both the nucleation and subsequent crystal growth. We proposed that the clusters played an important role in the retention of overall enzymatic activity by sacrificing protein molecules on the cluster surface. This work offers fresh perspectives on protein behaviors in the formation of P@MOFs, inspiring future endeavors in the design and development of artificial bionanocomposites with high biological activities.
Collapse
Affiliation(s)
- Yu Liu
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Shitong Cui
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Wenjun Ma
- The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Yibo Wu
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Ruobing Xin
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Yunxiu Bai
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Zhuo Chen
- The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Jianhong Xu
- The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Jun Ge
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
- Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, China
| |
Collapse
|
3
|
Lacouture C, Chaves B, Guipouy D, Houmadi R, Duplan-Eche V, Allart S, Destainville N, Dupré L. LFA-1 nanoclusters integrate TCR stimulation strength to tune T-cell cytotoxic activity. Nat Commun 2024; 15:407. [PMID: 38195629 PMCID: PMC10776856 DOI: 10.1038/s41467-024-44688-3] [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: 02/05/2023] [Accepted: 12/29/2023] [Indexed: 01/11/2024] Open
Abstract
T-cell cytotoxic function relies on the cooperation between the highly specific but poorly adhesive T-cell receptor (TCR) and the integrin LFA-1. How LFA-1-mediated adhesion may scale with TCR stimulation strength is ill-defined. Here, we show that LFA-1 conformation activation scales with TCR stimulation to calibrate human T-cell cytotoxicity. Super-resolution microscopy analysis reveals that >1000 LFA-1 nanoclusters provide a discretized platform at the immunological synapse to translate TCR engagement and density of the LFA-1 ligand ICAM-1 into graded adhesion. Indeed, the number of high-affinity conformation LFA-1 nanoclusters increases as a function of TCR triggering strength. Blockade of LFA-1 conformational activation impairs adhesion to target cells and killing. However, it occurs at a lower TCR stimulation threshold than lytic granule exocytosis implying that it licenses, rather than directly controls, the killing decision. We conclude that the organization of LFA-1 into nanoclusters provides a calibrated system to adjust T-cell killing to the antigen stimulation strength.
Collapse
Affiliation(s)
- Claire Lacouture
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
- Laboratoire de Physique Théorique, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Beatriz Chaves
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
- National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, Brazil
- Computational Modeling Group, Oswaldo Cruz Foundation (Fiocruz), Eusébio, Brazil
| | - Delphine Guipouy
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
| | - Raïssa Houmadi
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
| | - Valérie Duplan-Eche
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
| | - Sophie Allart
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France
| | - Nicolas Destainville
- Laboratoire de Physique Théorique, Université de Toulouse, CNRS, UPS, Toulouse, France.
| | - Loïc Dupré
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), INSERM, CNRS, Toulouse III Paul Sabatier University, Toulouse, France.
- Department of Dermatology, Medical University of Vienna, Vienna, Austria.
| |
Collapse
|
4
|
Wu LG, Chan CY. Membrane transformations of fusion and budding. Nat Commun 2024; 15:21. [PMID: 38167896 PMCID: PMC10761761 DOI: 10.1038/s41467-023-44539-7] [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: 06/07/2023] [Accepted: 12/15/2023] [Indexed: 01/05/2024] Open
Abstract
Membrane fusion and budding mediate fundamental processes like intracellular trafficking, exocytosis, and endocytosis. Fusion is thought to open a nanometer-range pore that may subsequently close or dilate irreversibly, whereas budding transforms flat membranes into vesicles. Reviewing recent breakthroughs in real-time visualization of membrane transformations well exceeding this classical view, we synthesize a new model and describe its underlying mechanistic principles and functions. Fusion involves hemi-to-full fusion, pore expansion, constriction and/or closure while fusing vesicles may shrink, enlarge, or receive another vesicle fusion; endocytosis follows exocytosis primarily by closing Ω-shaped profiles pre-formed through the flat-to-Λ-to-Ω-shape transition or formed via fusion. Calcium/SNARE-dependent fusion machinery, cytoskeleton-dependent membrane tension, osmotic pressure, calcium/dynamin-dependent fission machinery, and actin/dynamin-dependent force machinery work together to generate fusion and budding modes differing in pore status, vesicle size, speed and quantity, controls release probability, synchronization and content release rates/amounts, and underlies exo-endocytosis coupling to maintain membrane homeostasis. These transformations, underlying mechanisms, and functions may be conserved for fusion and budding in general.
Collapse
Affiliation(s)
- Ling-Gang Wu
- National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA.
| | - Chung Yu Chan
- National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| |
Collapse
|
5
|
Xu X, Yin K, Xu S, Wang Z, Wu R. Mass spectrometry-based methods for investigating the dynamics and organization of the surfaceome: exploring potential clinical implications. Expert Rev Proteomics 2024; 21:99-113. [PMID: 38300624 PMCID: PMC10928381 DOI: 10.1080/14789450.2024.2314148] [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: 11/22/2023] [Accepted: 01/16/2024] [Indexed: 02/02/2024]
Abstract
INTRODUCTION Cell-surface proteins are extremely important for many cellular events, such as regulating cell-cell communication and cell-matrix interactions. Aberrant alterations in surface protein expression, modification (especially glycosylation), and interactions are directly related to human diseases. Systematic investigation of surface proteins advances our understanding of protein functions, cellular activities, and disease mechanisms, which will lead to identifying surface proteins as disease biomarkers and drug targets. AREAS COVERED In this review, we summarize mass spectrometry (MS)-based proteomics methods for global analysis of cell-surface proteins. Then, investigations of the dynamics of surface proteins are discussed. Furthermore, we summarize the studies for the surfaceome interaction networks. Additionally, biological applications of MS-based surfaceome analysis are included, particularly highlighting the significance in biomarker identification, drug development, and immunotherapies. EXPERT OPINION Modern MS-based proteomics provides an opportunity to systematically characterize proteins. However, due to the complexity of cell-surface proteins, the labor-intensive workflow, and the limit of clinical samples, comprehensive characterization of the surfaceome remains extraordinarily challenging, especially in clinical studies. Developing and optimizing surfaceome enrichment methods and utilizing automated sample preparation workflow can expand the applications of surfaceome analysis and deepen our understanding of the functions of cell-surface proteins.
Collapse
Affiliation(s)
- Xing Xu
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Kejun Yin
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Senhan Xu
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Zeyu Wang
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Ronghu Wu
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| |
Collapse
|
6
|
Żak A, Korshunova K, Rajtar N, Kulig W, Kepczynski M. Deciphering Lipid Arrangement in Phosphatidylserine/Phosphatidylcholine Mixed Membranes: Simulations and Experiments. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:18995-19007. [PMID: 38096496 PMCID: PMC10753890 DOI: 10.1021/acs.langmuir.3c03061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/24/2023] [Accepted: 11/26/2023] [Indexed: 12/27/2023]
Abstract
Phosphatidylserine (PS) exposure on the plasma membrane is crucial for many cellular processes including apoptotic cell recognition, blood clotting regulation, cellular signaling, and intercellular interactions. In this study, we investigated the arrangement of PS headgroups in mixed PS/phosphatidylcholine (PC) bilayers, serving as a simplified model of the outer leaflets of mammalian cell plasma membranes. Combining atomistic-scale molecular dynamics (MD) simulations with Langmuir monolayer experiments, we unraveled the mutual miscibility of POPC and POPS lipids and the intricate intermolecular interactions inherent to these membranes as well as the disparities in position and orientation of PC and PS headgroups. Our experiments revealed micrometer-scale miscibility at all mole fractions of POPC and POPS, marked by modest deviations from ideal mixing with no apparent microscale phase separation. The MD simulations, meanwhile, demonstrated that these deviations were due to strong electrostatic interactions between like-lipid pairs (POPC-POPC and POPS-POPS), culminating in lateral segregation and nanoscale clustering. Notably, PS headgroups profoundly affect the ordering of the lipid acyl chains, leading to lipid elongation and subtle PS protrusion above the zwitterionic membrane. In addition, PC headgroups are more tilted with respect to the membrane normal, while PS headgroups align at a smaller angle, making them more exposed to the surface of the mixed PC/PS membranes. These findings provide a detailed molecular-level account of the organization of mixed PC/PS membranes, corroborated by experimental data. The insights gained here extend our comprehension of the physiological role of PSs.
Collapse
Affiliation(s)
- Agata Żak
- Faculty
of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Ksenia Korshunova
- Department
of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Natan Rajtar
- Faculty
of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Waldemar Kulig
- Department
of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Mariusz Kepczynski
- Faculty
of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| |
Collapse
|
7
|
Melero A, Jiménez-Rojo N. Cracking the membrane lipid code. Curr Opin Cell Biol 2023; 83:102203. [PMID: 37437490 DOI: 10.1016/j.ceb.2023.102203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/01/2023] [Accepted: 06/16/2023] [Indexed: 07/14/2023]
Abstract
Why has nature acquired such a huge lipid repertoire? Although it would be theoretically possible to make a lipid bilayer fulfilling barrier functions with only one glycerophospholipid, there are diverse and numerous different lipid species. Lipids are heterogeneously distributed across the evolutionary tree with lipidomes evolving in parallel to organismal complexity. Moreover, lipids are different between organs and tissues and even within the same cell, different organelles have characteristic lipid signatures. At the molecular level, membranes are asymmetric and laterally heterogeneous. This lipid asymmetry at different scales indicates that these molecules may play very specific molecular functions in biology. Some of these roles have been recently uncovered: lipids have been shown to be essential in processes such as hypoxia and ferroptosis or in protein sorting and trafficking but many of them remain still unknown. In this review we will discuss the importance of understanding lipid diversity in biology across scales and we will share a toolbox with some of the emerging technologies that are helping us to uncover new lipid molecular functions in cell biology and, step by step, crack the membrane lipid code.
Collapse
Affiliation(s)
- Alejandro Melero
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, 1015 Lausanne, Switzerland
| | - Noemi Jiménez-Rojo
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), 48940, Leioa, Spain; Instituto Biofisika (UPV/EHU, CSIC), 48940, Leioa, Spain; Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain.
| |
Collapse
|
8
|
Sakamoto K, Akimoto T, Muramatsu M, Sansom MSP, Metzler R, Yamamoto E. Heterogeneous biological membranes regulate protein partitioning via fluctuating diffusivity. PNAS NEXUS 2023; 2:pgad258. [PMID: 37593200 PMCID: PMC10427746 DOI: 10.1093/pnasnexus/pgad258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 06/22/2023] [Accepted: 07/27/2023] [Indexed: 08/19/2023]
Abstract
Cell membranes phase separate into ordered L o and disordered L d domains depending on their compositions. This membrane compartmentalization is heterogeneous and regulates the localization of specific proteins related to cell signaling and trafficking. However, it is unclear how the heterogeneity of the membranes affects the diffusion and localization of proteins in L o and L d domains. Here, using Langevin dynamics simulations coupled with the phase-field (LDPF) method, we investigate several tens of milliseconds-scale diffusion and localization of proteins in heterogeneous biological membrane models showing phase separation into L o and L d domains. The diffusivity of proteins exhibits temporal fluctuations depending on the field composition. Increases in molecular concentrations and domain preference of the molecule induce subdiffusive behavior due to molecular collisions by crowding and confinement effects, respectively. Moreover, we quantitatively demonstrate that the protein partitioning into the L o domain is determined by the difference in molecular diffusivity between domains, molecular preference of domain, and molecular concentration. These results pave the way for understanding how biological reactions caused by molecular partitioning may be controlled in heterogeneous media. Moreover, the methodology proposed here is applicable not only to biological membrane systems but also to the study of diffusion and localization phenomena of molecules in various heterogeneous systems.
Collapse
Affiliation(s)
- Ken Sakamoto
- Department of System Design Engineering, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Takuma Akimoto
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Mayu Muramatsu
- Department of Mechanical Engineering, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Ralf Metzler
- Institute of Physics & Astronomy, University of Potsdam, Potsdam-Golm 14476, Germany
- Asia Pacific Centre for Theoretical Physics, Pohang 37673, Republic of Korea
| | - Eiji Yamamoto
- Department of System Design Engineering, Keio University, Yokohama, Kanagawa 223-8522, Japan
| |
Collapse
|
9
|
Role of the membrane anchor in the regulation of Lck activity. J Biol Chem 2022; 298:102663. [PMID: 36372231 PMCID: PMC9763865 DOI: 10.1016/j.jbc.2022.102663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/13/2022] Open
Abstract
Theoretical work suggests that collective spatiotemporal behavior of integral membrane proteins should be modulated by boundary lipids sheathing their membrane anchors. Here, we show evidence for this prediction while investigating the mechanism for maintaining a steady amount of the active form of integral membrane protein Lck kinase (LckA) by Lck trans-autophosphorylation regulated by the phosphatase CD45. We used super-resolution microscopy, flow cytometry, and pharmacological and genetic perturbation to gain insight into the spatiotemporal context of this process. We found that LckA is generated exclusively at the plasma membrane, where CD45 maintains it in a ceaseless dynamic equilibrium with its unphosphorylated precursor. Steady LckA shows linear dependence, after an initial threshold, over a considerable range of Lck expression levels. This behavior fits a phenomenological model of trans-autophosphorylation that becomes more efficient with increasing LckA. We then challenged steady LckA formation by genetically swapping the Lck membrane anchor with structurally divergent ones, such as that of Src or the transmembrane domains of LAT, CD4, palmitoylation-defective CD4 and CD45 that were expected to drastically modify Lck boundary lipids. We observed small but significant changes in LckA generation, except for the CD45 transmembrane domain that drastically reduced LckA due to its excessive lateral proximity to CD45. Comprehensively, LckA formation and maintenance can be best explained by lipid bilayer critical density fluctuations rather than liquid-ordered phase-separated nanodomains, as previously thought, with "like/unlike" boundary lipids driving dynamical proximity and remoteness of Lck with itself and with CD45.
Collapse
|
10
|
Kovacs T, Nagy P, Panyi G, Szente L, Varga Z, Zakany F. Cyclodextrins: Only Pharmaceutical Excipients or Full-Fledged Drug Candidates? Pharmaceutics 2022; 14:pharmaceutics14122559. [PMID: 36559052 PMCID: PMC9788615 DOI: 10.3390/pharmaceutics14122559] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
Cyclodextrins, representing a versatile family of cyclic oligosaccharides, have extensive pharmaceutical applications due to their unique truncated cone-shaped structure with a hydrophilic outer surface and a hydrophobic cavity, which enables them to form non-covalent host-guest inclusion complexes in pharmaceutical formulations to enhance the solubility, stability and bioavailability of numerous drug molecules. As a result, cyclodextrins are mostly considered as inert carriers during their medical application, while their ability to interact not only with small molecules but also with lipids and proteins is largely neglected. By forming inclusion complexes with cholesterol, cyclodextrins deplete cholesterol from cellular membranes and thereby influence protein function indirectly through alterations in biophysical properties and lateral heterogeneity of bilayers. In this review, we summarize the general chemical principles of direct cyclodextrin-protein interactions and highlight, through relevant examples, how these interactions can modify protein functions in vivo, which, despite their huge potential, have been completely unexploited in therapy so far. Finally, we give a brief overview of disorders such as Niemann-Pick type C disease, atherosclerosis, Alzheimer's and Parkinson's disease, in which cyclodextrins already have or could have the potential to be active therapeutic agents due to their cholesterol-complexing or direct protein-targeting properties.
Collapse
Affiliation(s)
- Tamas Kovacs
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Peter Nagy
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Lajos Szente
- CycloLab Cyclodextrin R & D Laboratory Ltd., H-1097 Budapest, Hungary
| | - Zoltan Varga
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Florina Zakany
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
- Correspondence:
| |
Collapse
|
11
|
Bag N, London E, Holowka DA, Baird BA. Transbilayer Coupling of Lipids in Cells Investigated by Imaging Fluorescence Correlation Spectroscopy. J Phys Chem B 2022; 126:2325-2336. [PMID: 35294838 DOI: 10.1021/acs.jpcb.2c00117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Plasma membranes host numerous receptors, sensors, and ion channels involved in cellular signaling. Phase separation within the plasma membrane has emerged as a key biophysical regulator of signaling reactions in multiple physiological and pathological contexts. There is much evidence that plasma membrane composition supports the coexistence of liquid-ordered (Lo) and liquid-disordered (Ld) phases or domains at physiological conditions. However, this phase/domain separation is nanoscopic and transient in live cells. It has been recently proposed that transbilayer coupling between the inner and outer leaflets of the plasma membrane is driven by their asymmetric lipid distribution and by dynamic cytoskeleton-lipid composites that contribute to the formation and transience of Lo/Ld phase separation in live cells. In this Perspective, we highlight new approaches to investigate how transbilayer coupling may influence phase separation. For quantitative evaluation of the impact of these interactions, we introduce an experimental strategy centered around Imaging Fluorescence Correlation Spectroscopy (ImFCS), which measures membrane diffusion with very high precision. To demonstrate this strategy, we choose two well-established model systems for transbilayer interactions: cross-linking by multivalent antigen of immunoglobulin E bound to receptor FcεRI and cross-linking by cholera toxin B of GM1 gangliosides. We discuss emerging methods to systematically perturb membrane lipid composition, particularly exchange of outer leaflet lipids with exogenous lipids using methyl alpha cyclodextrin. These selective perturbations may be quantitatively evaluated with ImFCS and other high-resolution biophysical tools to discover novel principles of lipid-mediated phase separation in live cells in the context of their pathophysiological relevance.
Collapse
Affiliation(s)
- Nirmalya Bag
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Erwin London
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York 11794, United States
| | - David A Holowka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Barbara A Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| |
Collapse
|
12
|
Approach to map nanotopography of cell surface receptors. Commun Biol 2022; 5:218. [PMID: 35264712 PMCID: PMC8907216 DOI: 10.1038/s42003-022-03152-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 02/09/2022] [Indexed: 12/18/2022] Open
Abstract
Cells communicate with their environment via surface receptors, but nanoscopic receptor organization with respect to complex cell surface morphology remains unclear. This is mainly due to a lack of accessible, robust and high-resolution methods. Here, we present an approach for mapping the topography of receptors at the cell surface with nanometer precision. The method involves coating glass coverslips with glycine, which preserves the fine membrane morphology while allowing immobilized cells to be positioned close to the optical surface. We developed an advanced and simplified algorithm for the analysis of single-molecule localization data acquired in a biplane detection scheme. These advancements enable direct and quantitative mapping of protein distribution on ruffled plasma membranes with near isotropic 3D nanometer resolution. As demonstrated successfully for CD4 and CD45 receptors, the described workflow is a straightforward quantitative technique to study molecules and their interactions at the complex surface nanomorphology of differentiated metazoan cells. A super-resolution localisation-based method is shown to map receptor topography in immune cells, which allows quantitative study of molecules and their interactions at the complex surface nanomorphology of cells.
Collapse
|
13
|
Dankovich TM, Rizzoli SO. The Synaptic Extracellular Matrix: Long-Lived, Stable, and Still Remarkably Dynamic. Front Synaptic Neurosci 2022; 14:854956. [PMID: 35350469 PMCID: PMC8957932 DOI: 10.3389/fnsyn.2022.854956] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/16/2022] [Indexed: 01/09/2023] Open
Abstract
In the adult brain, synapses are tightly enwrapped by lattices of the extracellular matrix that consist of extremely long-lived molecules. These lattices are deemed to stabilize synapses, restrict the reorganization of their transmission machinery, and prevent them from undergoing structural or morphological changes. At the same time, they are expected to retain some degree of flexibility to permit occasional events of synaptic plasticity. The recent understanding that structural changes to synapses are significantly more frequent than previously assumed (occurring even on a timescale of minutes) has called for a mechanism that allows continual and energy-efficient remodeling of the extracellular matrix (ECM) at synapses. Here, we review recent evidence for such a process based on the constitutive recycling of synaptic ECM molecules. We discuss the key characteristics of this mechanism, focusing on its roles in mediating synaptic transmission and plasticity, and speculate on additional potential functions in neuronal signaling.
Collapse
Affiliation(s)
- Tal M. Dankovich
- University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Göttingen, Germany
- International Max Planck Research School for Neuroscience, Göttingen, Germany
- *Correspondence: Tal M. Dankovich Silvio O. Rizzoli
| | - Silvio O. Rizzoli
- University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Göttingen, Germany
- Biostructural Imaging of Neurodegeneration (BIN) Center & Multiscale Bioimaging Excellence Center, Göttingen, Germany
- *Correspondence: Tal M. Dankovich Silvio O. Rizzoli
| |
Collapse
|
14
|
It Takes More than Two to Tango: Complex, Hierarchal, and Membrane-Modulated Interactions in the Regulation of Receptor Tyrosine Kinases. Cancers (Basel) 2022; 14:cancers14040944. [PMID: 35205690 PMCID: PMC8869822 DOI: 10.3390/cancers14040944] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/09/2022] [Accepted: 02/12/2022] [Indexed: 12/18/2022] Open
Abstract
The search for an understanding of how cell fate and motility are regulated is not a purely scientific undertaking, but it can also lead to rationally designed therapies against cancer. The discovery of tyrosine kinases about half a century ago, the subsequent characterization of certain transmembrane receptors harboring tyrosine kinase activity, and their connection to the development of human cancer ushered in a new age with the hope of finding a treatment for malignant diseases in the foreseeable future. However, painstaking efforts were required to uncover the principles of how these receptors with intrinsic tyrosine kinase activity are regulated. Developments in molecular and structural biology and biophysical approaches paved the way towards better understanding of these pathways. Discoveries in the past twenty years first resulted in the formulation of textbook dogmas, such as dimerization-driven receptor association, which were followed by fine-tuning the model. In this review, the role of molecular interactions taking place during the activation of receptor tyrosine kinases, with special attention to the epidermal growth factor receptor family, will be discussed. The fact that these receptors are anchored in the membrane provides ample opportunities for modulatory lipid-protein interactions that will be considered in detail in the second part of the manuscript. Although qualitative and quantitative alterations in lipids in cancer are not sufficient in their own right to drive the malignant transformation, they both contribute to tumor formation and also provide ways to treat cancer. The review will be concluded with a summary of these medical aspects of lipid-protein interactions.
Collapse
|
15
|
Bagheri Y, Ali AA, Keshri P, Chambers J, Gershenson A, You M. Imaging Membrane Order and Dynamic Interactions in Living Cells with a DNA Zipper Probe. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202112033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yousef Bagheri
- Department of Chemistry University of Massachusetts Amherst MA 01003 USA
| | - Ahsan Ausaf Ali
- Department of Chemistry University of Massachusetts Amherst MA 01003 USA
| | - Puspam Keshri
- Department of Chemistry University of Massachusetts Amherst MA 01003 USA
| | - James Chambers
- Institute for Applied Life Sciences University of Massachusetts Amherst MA 01003 USA
| | - Anne Gershenson
- Department of Biochemistry and Molecular Biology University of Massachusetts Amherst MA 01003 USA
| | - Mingxu You
- Department of Chemistry University of Massachusetts Amherst MA 01003 USA
| |
Collapse
|
16
|
Bagheri Y, Ali AA, Keshri P, Chambers J, Gershenson A, You M. Imaging Membrane Order and Dynamic Interactions in Living Cells with a DNA Zipper Probe. Angew Chem Int Ed Engl 2022; 61:e202112033. [PMID: 34767659 PMCID: PMC8792286 DOI: 10.1002/anie.202112033] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/19/2021] [Indexed: 02/03/2023]
Abstract
The cell membrane is a dynamic and heterogeneous structure composed of distinct sub-compartments. Within these compartments, preferential interactions occur among various lipids and proteins. Currently, it is still challenging to image these short-lived membrane complexes, especially in living cells. In this work, we present a DNA-based probe, termed "DNA Zipper", which allows the membrane order and pattern of transient interactions to be imaged in living cells using standard fluorescence microscopes. By fine-tuning the length and binding affinity of DNA duplex, these probes can precisely extend the duration of membrane lipid interactions via dynamic DNA hybridization. The correlation between membrane order and the activation of T-cell receptor signaling has also been studied. These programmable DNA probes function after a brief cell incubation, which can be easily adapted to study lipid interactions and membrane order during different membrane signaling events.
Collapse
Affiliation(s)
- Yousef Bagheri
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003 (USA)
| | - Ahsan Ausaf Ali
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003 (USA)
| | - Puspam Keshri
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003 (USA)
| | - James Chambers
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA 01003 (USA)
| | - Anne Gershenson
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, MA 01003 (USA)
| | - Mingxu You
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003 (USA)
| |
Collapse
|
17
|
Nieto-Garai JA, Lorizate M, Contreras FX. Shedding light on membrane rafts structure and dynamics in living cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2022; 1864:183813. [PMID: 34748743 DOI: 10.1016/j.bbamem.2021.183813] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/21/2021] [Accepted: 10/25/2021] [Indexed: 12/12/2022]
Abstract
Cellular membranes are fundamental building blocks regulating an extensive repertoire of biological functions. These structures contain lipids and membrane proteins that are known to laterally self-aggregate in the plane of the membrane, forming defined membrane nanoscale domains essential for protein activity. Membrane rafts are described as heterogeneous, dynamic, and short-lived cholesterol- and sphingolipid-enriched membrane nanodomains (10-200 nm) induced by lipid-protein and lipid-lipid interactions. Those membrane nanodomains have been extensively characterized using model membranes and in silico methods. However, despite the development of advanced fluorescence microscopy techniques, undoubted nanoscale visualization by imaging techniques of membrane rafts in the membrane of unperturbed living cells is still uncompleted, increasing the skepticism about their existence. Here, we broadly review recent biochemical and microscopy techniques used to investigate membrane rafts in living cells and we enumerate persistent open questions to answer before unlocking the mystery of membrane rafts in living cells.
Collapse
Affiliation(s)
- Jon Ander Nieto-Garai
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Bilbao, Spain.
| | - Maier Lorizate
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Bilbao, Spain; Instituto Biofisika (UPV/EHU, CSIC), Barrio Sarriena s/n, 48940 Bilbao, Spain
| | - F-Xabier Contreras
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Bilbao, Spain; Instituto Biofisika (UPV/EHU, CSIC), Barrio Sarriena s/n, 48940 Bilbao, Spain; IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain.
| |
Collapse
|
18
|
Dankovich TM, Kaushik R, Olsthoorn LHM, Petersen GC, Giro PE, Kluever V, Agüi-Gonzalez P, Grewe K, Bao G, Beuermann S, Hadi HA, Doeren J, Klöppner S, Cooper BH, Dityatev A, Rizzoli SO. Extracellular matrix remodeling through endocytosis and resurfacing of Tenascin-R. Nat Commun 2021; 12:7129. [PMID: 34880248 PMCID: PMC8654841 DOI: 10.1038/s41467-021-27462-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/19/2021] [Indexed: 01/22/2023] Open
Abstract
The brain extracellular matrix (ECM) consists of extremely long-lived proteins that assemble around neurons and synapses, to stabilize them. The ECM is thought to change only rarely, in relation to neuronal plasticity, through ECM proteolysis and renewed protein synthesis. We report here an alternative ECM remodeling mechanism, based on the recycling of ECM molecules. Using multiple ECM labeling and imaging assays, from super-resolution optical imaging to nanoscale secondary ion mass spectrometry, both in culture and in brain slices, we find that a key ECM protein, Tenascin-R, is frequently endocytosed, and later resurfaces, preferentially near synapses. The TNR molecules complete this cycle within ~3 days, in an activity-dependent fashion. Interfering with the recycling process perturbs severely neuronal function, strongly reducing synaptic vesicle exo- and endocytosis. We conclude that the neuronal ECM can be remodeled frequently through mechanisms that involve endocytosis and recycling of ECM proteins.
Collapse
Affiliation(s)
- Tal M. Dankovich
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany ,grid.4372.20000 0001 2105 1091International Max Planck Research School for Neuroscience, Göttingen, Germany
| | - Rahul Kaushik
- grid.424247.30000 0004 0438 0426Molecular Neuroplasticity, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany ,grid.418723.b0000 0001 2109 6265Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Linda H. M. Olsthoorn
- grid.4372.20000 0001 2105 1091International Max Planck Research School for Neuroscience, Göttingen, Germany ,grid.418140.80000 0001 2104 4211Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Gabriel Cassinelli Petersen
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Philipp Emanuel Giro
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Verena Kluever
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Paola Agüi-Gonzalez
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Katharina Grewe
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Guobin Bao
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany ,grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute of Pharmacology and Toxicology, Göttingen, Germany
| | - Sabine Beuermann
- grid.419522.90000 0001 0668 6902Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Hannah Abdul Hadi
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Jose Doeren
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Simon Klöppner
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany
| | - Benjamin H. Cooper
- grid.419522.90000 0001 0668 6902Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Alexander Dityatev
- grid.424247.30000 0004 0438 0426Molecular Neuroplasticity, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany ,grid.418723.b0000 0001 2109 6265Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany ,grid.5807.a0000 0001 1018 4307Medical Faculty, Otto von Guericke University, Magdeburg, Germany
| | - Silvio O. Rizzoli
- grid.411984.10000 0001 0482 5331University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Excellence Cluster Multiscale Bioimaging, Göttingen, Germany ,Biostructural Imaging of Neurodegeneration (BIN) Center, Göttingen, Germany
| |
Collapse
|
19
|
Mertins J, Finke J, Sies R, Rink KM, Hasenauer J, Lang T. The mesoscale organization of syntaxin 1A and SNAP25 is determined by SNARE-SNARE interactions. eLife 2021; 10:69236. [PMID: 34779769 PMCID: PMC8629428 DOI: 10.7554/elife.69236] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 11/14/2021] [Indexed: 01/01/2023] Open
Abstract
SNARE proteins have been described as the effectors of fusion events in the secretory pathway more than two decades ago. The strong interactions between SNARE domains are clearly important in membrane fusion, but it is unclear whether they are involved in any other cellular processes. Here, we analyzed two classical SNARE proteins, syntaxin 1A and SNAP25. Although they are supposed to be engaged in tight complexes, we surprisingly find them largely segregated in the plasma membrane. Syntaxin 1A only occupies a small fraction of the plasma membrane area. Yet, we find it is able to redistribute the far more abundant SNAP25 on the mesoscale by gathering crowds of SNAP25 molecules onto syntaxin clusters in a SNARE-domain-dependent manner. Our data suggest that SNARE domain interactions are not only involved in driving membrane fusion on the nanoscale, but also play an important role in controlling the general organization of proteins on the mesoscale. Further, we propose these mechanisms preserve active syntaxin 1A–SNAP25 complexes at the plasma membrane.
Collapse
Affiliation(s)
- Jasmin Mertins
- Departments of Membrane Biochemistry, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
| | - Jérôme Finke
- Departments of Membrane Biochemistry, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
| | - Ricarda Sies
- Departments of Membrane Biochemistry, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
| | - Kerstin M Rink
- Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany
| | - Jan Hasenauer
- Computational Life Sciences, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Interdisciplinary Research Unit Mathematics and Life Sciences, University of Bonn, Bonn, Germany.,Institute of Computational Biology, Helmholtz Center Munich - German Research Center for Environmental Health, Neuherberg, Germany
| | - Thorsten Lang
- Departments of Membrane Biochemistry, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
| |
Collapse
|
20
|
Winkler PM, García-Parajo MF. Correlative nanophotonic approaches to enlighten the nanoscale dynamics of living cell membranes. Biochem Soc Trans 2021; 49:2357-2369. [PMID: 34495333 PMCID: PMC8589428 DOI: 10.1042/bst20210457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/03/2021] [Accepted: 08/10/2021] [Indexed: 01/31/2023]
Abstract
Dynamic compartmentalization is a prevailing principle regulating the spatiotemporal organization of the living cell membrane from the nano- up to the mesoscale. This non-arbitrary organization is intricately linked to cell function. On living cell membranes, dynamic domains or 'membrane rafts' enriched with cholesterol, sphingolipids and other certain proteins exist at the nanoscale serving as signaling and sorting platforms. Moreover, it has been postulated that other local organizers of the cell membrane such as intrinsic protein interactions, the extracellular matrix and/or the actin cytoskeleton synergize with rafts to provide spatiotemporal hierarchy to the membrane. Elucidating the intricate coupling of multiple spatial and temporal scales requires the application of correlative techniques, with a particular need for simultaneous nanometer spatial precision and microsecond temporal resolution. Here, we review novel fluorescence-based techniques that readily allow to decode nanoscale membrane dynamics with unprecedented spatiotemporal resolution and single-molecule sensitivity. We particularly focus on correlative approaches from the field of nanophotonics. Notably, we introduce a versatile planar nanoantenna platform combined with fluorescence correlation spectroscopy to study spatiotemporal heterogeneities on living cell membranes at the nano- up to the mesoscale. Finally, we outline remaining future technological challenges and comment on potential directions to advance our understanding of cell membrane dynamics under the influence of the actin cytoskeleton and extracellular matrix in uttermost detail.
Collapse
Affiliation(s)
- Pamina M. Winkler
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Barcelona, Spain
| | - María F. García-Parajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Barcelona, Spain
- ICREA, Pg. Lluis Companys 23, 08010 Barcelona, Spain
| |
Collapse
|
21
|
Feher K, Graus MS, Coelho S, Farrell MV, Goyette J, Gaus K. K-Neighbourhood Analysis: A Method for Understanding SMLM Images as Compositions of Local Neighbourhoods. FRONTIERS IN BIOINFORMATICS 2021; 1:724127. [PMID: 36303786 PMCID: PMC9581049 DOI: 10.3389/fbinf.2021.724127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 10/04/2021] [Indexed: 11/30/2022] Open
Abstract
Single molecule localisation microscopy (SMLM) is a powerful tool that has revealed the spatial arrangement of cell surface signalling proteins, producing data of enormous complexity. The complexity is partly driven by the convolution of technical and biological signal components, and partly by the challenge of pooling information across many distinct cells. To address these two particular challenges, we have devised a novel algorithm called K-neighbourhood analysis (KNA), which emphasises the fact that each image can also be viewed as a composition of local neighbourhoods. KNA is based on a novel transformation, spatial neighbourhood principal component analysis (SNPCA), which is defined by the PCA of the normalised K-nearest neighbour vectors of a spatially random point pattern. Here, we use KNA to define a novel visualisation of individual images, to compare within and between groups of images and to investigate the preferential patterns of phosphorylation. This methodology is also highly flexible and can be used to augment existing clustering methods by providing clustering diagnostics as well as revealing substructure within microclusters. In summary, we have presented a highly flexible analysis tool that presents new conceptual possibilities in the analysis of SMLM images.
Collapse
Affiliation(s)
- Kristen Feher
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
| | - Matthew S. Graus
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
| | - Simao Coelho
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Megan V. Farrell
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
| | - Jesse Goyette
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
| | - Katharina Gaus
- School of Medical Sciences, EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, NSW, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
22
|
Kutz S, Zehrer AC, Svetlitckii R, Gülcüler Balta GS, Galli L, Kleber S, Rentsch J, Martin-Villalba A, Ewers H. An Efficient GUI-Based Clustering Software for Simulation and Bayesian Cluster Analysis of Single-Molecule Localization Microscopy Data. FRONTIERS IN BIOINFORMATICS 2021; 1:723915. [PMID: 36303736 PMCID: PMC9581037 DOI: 10.3389/fbinf.2021.723915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/17/2021] [Indexed: 11/13/2022] Open
Abstract
Ligand binding of membrane proteins triggers many important cellular signaling events by the lateral aggregation of ligand-bound and other membrane proteins in the plane of the plasma membrane. This local clustering can lead to the co-enrichment of molecules that create an intracellular signal or bring sufficient amounts of activity together to shift an existing equilibrium towards the execution of a signaling event. In this way, clustering can serve as a cellular switch. The underlying uneven distribution and local enrichment of the signaling cluster’s constituting membrane proteins can be used as a functional readout. This information is obtained by combining single-molecule fluorescence microscopy with cluster algorithms that can reliably and reproducibly distinguish clusters from fluctuations in the background noise to generate quantitative data on this complex process. Cluster analysis of single-molecule fluorescence microscopy data has emerged as a proliferative field, and several algorithms and software solutions have been put forward. However, in most cases, such cluster algorithms require multiple analysis parameters to be defined by the user, which may lead to biased results. Furthermore, most cluster algorithms neglect the individual localization precision connected to every localized molecule, leading to imprecise results. Bayesian cluster analysis has been put forward to overcome these problems, but so far, it has entailed high computational cost, increasing runtime drastically. Finally, most software is challenging to use as they require advanced technical knowledge to operate. Here we combined three advanced cluster algorithms with the Bayesian approach and parallelization in a user-friendly GUI and achieved up to an order of magnitude faster processing than for previous approaches. Our work will simplify access to a well-controlled analysis of clustering data generated by SMLM and significantly accelerate data processing. The inclusion of a simulation mode aids in the design of well-controlled experimental assays.
Collapse
Affiliation(s)
- Saskia Kutz
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
| | - Ando C. Zehrer
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
| | | | - Gülce S. Gülcüler Balta
- Department of Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Lucrezia Galli
- Department of Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Susanne Kleber
- Department of Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jakob Rentsch
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
| | - Ana Martin-Villalba
- Department of Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Helge Ewers
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
- *Correspondence: Helge Ewers,
| |
Collapse
|
23
|
Binotti B, Jahn R, Pérez-Lara Á. An overview of the synaptic vesicle lipid composition. Arch Biochem Biophys 2021; 709:108966. [PMID: 34139199 DOI: 10.1016/j.abb.2021.108966] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/10/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
Chemical neurotransmission is the major mechanism of neuronal communication. Neurotransmitters are released from secretory organelles, the synaptic vesicles (SVs) via exocytosis into the synaptic cleft. Fusion of SVs with the presynaptic plasma membrane is balanced by endocytosis, thus maintaining the presynaptic membrane at steady-state levels. The protein machineries responsible for exo- and endocytosis have been extensively investigated. In contrast, less is known about the role of lipids in synaptic transmission and how the lipid composition of SVs is affected by dynamic exo-endocytotic cycling. Here we summarize the current knowledge about the composition, organization, and function of SV membrane lipids. We also cover lipid biogenesis and maintenance during the synaptic vesicle cycle.
Collapse
Affiliation(s)
- Beyenech Binotti
- Department of Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| | - Ángel Pérez-Lara
- Department of Physical Chemistry, University of Granada, Campus Universitario de Cartuja, 18071, Granada, Spain.
| |
Collapse
|
24
|
Mioka T, Guo T, Wang S, Tsuji T, Kishimoto T, Fujimoto T, Tanaka K. Characterization of micron-scale protein-depleted plasma membrane domains in phosphatidylserine-deficient yeast cells. J Cell Sci 2021; 135:261783. [PMID: 34000034 DOI: 10.1242/jcs.256529] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/16/2021] [Indexed: 12/30/2022] Open
Abstract
Membrane phase separation to form micron-scale domains of lipids and proteins occurs in artificial membranes; however, a similar large-scale phase separation has not been reported in the plasma membrane of the living cells. We show here that a stable micron-scale protein-depleted region is generated in the plasma membrane of yeast mutants lacking phosphatidylserine at high temperatures. We named this region the 'void zone'. Transmembrane proteins and certain peripheral membrane proteins and phospholipids are excluded from the void zone. The void zone is rich in ergosterol, and requires ergosterol and sphingolipids for its formation. Such properties are also found in the cholesterol-enriched domains of phase-separated artificial membranes, but the void zone is a novel membrane domain that requires energy and various cellular functions for its formation. The formation of the void zone indicates that the plasma membrane in living cells has the potential to undergo phase separation with certain lipid compositions. We also found that void zones were frequently in contact with vacuoles, in which a membrane domain was also formed at the contact site.
Collapse
Affiliation(s)
- Tetsuo Mioka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Tian Guo
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Shiyao Wang
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Takuma Tsuji
- Laboratory of Molecular Cell Biology, Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Takuma Kishimoto
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Toyoshi Fujimoto
- Laboratory of Molecular Cell Biology, Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Kazuma Tanaka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| |
Collapse
|
25
|
Sych T, Gurdap CO, Wedemann L, Sezgin E. How Does Liquid-Liquid Phase Separation in Model Membranes Reflect Cell Membrane Heterogeneity? MEMBRANES 2021; 11:323. [PMID: 33925240 PMCID: PMC8146956 DOI: 10.3390/membranes11050323] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/22/2022]
Abstract
Although liquid-liquid phase separation of cytoplasmic or nuclear components in cells has been a major focus in cell biology, it is only recently that the principle of phase separation has been a long-standing concept and extensively studied in biomembranes. Membrane phase separation has been reconstituted in simplified model systems, and its detailed physicochemical principles, including essential phase diagrams, have been extensively explored. These model membrane systems have proven very useful to study the heterogeneity in cellular membranes, however, concerns have been raised about how reliably they can represent native membranes. In this review, we will discuss how phase-separated membrane systems can mimic cellular membranes and where they fail to reflect the native cell membrane heterogeneity. We also include a few humble suggestions on which phase-separated systems should be used for certain applications, and which interpretations should be avoided to prevent unreliable conclusions.
Collapse
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.)
| |
Collapse
|
26
|
Yuan Y, Jacobs CA, Llorente Garcia I, Pereira PM, Lawrence SP, Laine RF, Marsh M, Henriques R. Single-Molecule Super-Resolution Imaging of T-Cell Plasma Membrane CD4 Redistribution upon HIV-1 Binding. Viruses 2021; 13:142. [PMID: 33478139 PMCID: PMC7835772 DOI: 10.3390/v13010142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 12/21/2022] Open
Abstract
The first step of cellular entry for the human immunodeficiency virus type-1 (HIV-1) occurs through the binding of its envelope protein (Env) with the plasma membrane receptor CD4 and co-receptor CCR5 or CXCR4 on susceptible cells, primarily CD4+ T cells and macrophages. Although there is considerable knowledge of the molecular interactions between Env and host cell receptors that lead to successful fusion, the precise way in which HIV-1 receptors redistribute to sites of virus binding at the nanoscale remains unknown. Here, we quantitatively examine changes in the nanoscale organisation of CD4 on the surface of CD4+ T cells following HIV-1 binding. Using single-molecule super-resolution imaging, we show that CD4 molecules are distributed mostly as either individual molecules or small clusters of up to 4 molecules. Following virus binding, we observe a local 3-to-10-fold increase in cluster diameter and molecule number for virus-associated CD4 clusters. Moreover, a similar but smaller magnitude reorganisation of CD4 was also observed with recombinant gp120. For one of the first times, our results quantify the nanoscale CD4 reorganisation triggered by HIV-1 on host CD4+ T cells. Our quantitative approach provides a robust methodology for characterising the nanoscale organisation of plasma membrane receptors in general with the potential to link spatial organisation to function.
Collapse
Affiliation(s)
- Yue Yuan
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
| | - Caron A. Jacobs
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape Town, Cape Town 7925, South Africa
| | | | - Pedro M. Pereira
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
- Bacterial Cell Biology, MOSTMICRO, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal
| | - Scott P. Lawrence
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
| | - Romain F. Laine
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
- The Francis Crick Institute, London NW1 1AT, UK
| | - Mark Marsh
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; (Y.Y.); (C.A.J.); (P.M.P.); (S.P.L.)
- The Francis Crick Institute, London NW1 1AT, UK
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| |
Collapse
|
27
|
Chen J, Li H, Wu Q, Yan Q, Sun J, Liang F, Liu Y, Wang H. Organization of Protein Tyrosine Kinase-7 on Cell Membranes Characterized by Aptamer Probe-Based STORM Imaging. Anal Chem 2020; 93:936-945. [PMID: 33301288 DOI: 10.1021/acs.analchem.0c03630] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Protein tyrosine kinase-7 (PTK7), as an important membrane receptor, regulates various cellular activities, including cell polarity, movement, migration, and invasion. Although lots of research studies focused on revealing its functions from the aspect of the expression of the gene and protein are present, the relationship between the spatial distribution at the single-molecule level and the function remains unclear. Through combining aptamer probe labeling and super-resolution imaging technology, after verifying the specificity and superiority of the aptamer probe, a more significant clustering distribution of PTK7 is found on the MCF10A cell basal membrane than on the apical membrane, which is thought to be related to their specific functions on different membranes. By exploring the relationship between the assembly of PTK7 and lipid rafts, actin cytoskeleton, and carbohydrate chains on the membrane, the unique distribution of PTK7 on disparate membranes is revealed to be probably because of the varied dominant position of these three factors. These findings present the detailed spatial information of PTK7 and the related potential organization mechanism on the cell membrane, which will facilitate a better understanding of the relationship between the molecular assembly and its function, as well as the overall structure of the cell membrane.
Collapse
Affiliation(s)
- Junling Chen
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. China.,State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China
| | - Hongru Li
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China.,University of Science and Technology of China, Hefei 230026, P. R. China
| | - Qiang Wu
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. China
| | - Qiuyan Yan
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China
| | - Jiayin Sun
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China
| | - Feng Liang
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. China
| | - Yi Liu
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. China.,Key Laboratory of Analytical Chemistry for Biology and Medicine (MOE) & Sauvage Center for Molecular Sciences, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, P. R. China.,University of Science and Technology of China, Hefei 230026, P. R. China
| |
Collapse
|
28
|
Bagheri Y, Ali AA, You M. Current Methods for Detecting Cell Membrane Transient Interactions. Front Chem 2020; 8:603259. [PMID: 33365301 PMCID: PMC7750205 DOI: 10.3389/fchem.2020.603259] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 10/16/2020] [Indexed: 12/28/2022] Open
Abstract
Short-lived cell membrane complexes play a key role in regulating cell signaling and communication. Many of these complexes are formed based on low-affinity and transient interactions among various lipids and proteins. New techniques have emerged to study these previously overlooked membrane transient interactions. Exciting functions of these transient interactions have been discovered in cellular events such as immune signaling, host-pathogen interactions, and diseases such as cancer. In this review, we have summarized current experimental methods that allow us to detect and analyze short-lived cell membrane protein-protein, lipid-protein, and lipid-lipid interactions. These methods can provide useful information about the strengths, kinetics, and/or spatial patterns of membrane transient interactions. However, each method also has its own limitations. We hope this review can be used as a guideline to help the audience to choose proper approaches for studying membrane transient interactions in different membrane trafficking and cell signaling events.
Collapse
Affiliation(s)
| | | | - Mingxu You
- Department of Chemistry, University of Massachusetts, Amherst, MA, United States
| |
Collapse
|
29
|
Complementary mesoscale dynamics of spectrin and acto-myosin shape membrane territories during mechanoresponse. Nat Commun 2020; 11:5108. [PMID: 33037189 PMCID: PMC7547731 DOI: 10.1038/s41467-020-18825-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 09/11/2020] [Indexed: 11/08/2022] Open
Abstract
The spectrin-based membrane skeleton is a major component of the cell cortex. While expressed by all metazoans, its dynamic interactions with the other cortex components, including the plasma membrane or the acto-myosin cytoskeleton, are poorly understood. Here, we investigate how spectrin re-organizes spatially and dynamically under the membrane during changes in cell mechanics. We find spectrin and acto-myosin to be spatially distinct but cooperating during mechanical challenges, such as cell adhesion and contraction, or compression, stretch and osmolarity fluctuations, creating a cohesive cortex supporting the plasma membrane. Actin territories control protrusions and contractile structures while spectrin territories concentrate in retractile zones and low-actin density/inter-contractile regions, acting as a fence that organize membrane trafficking events. We unveil here the existence of a dynamic interplay between acto-myosin and spectrin necessary to support a mesoscale organization of the lipid bilayer into spatially-confined cortical territories during cell mechanoresponse.
Collapse
|
30
|
Quantitative Synaptic Biology: A Perspective on Techniques, Numbers and Expectations. Int J Mol Sci 2020; 21:ijms21197298. [PMID: 33023247 PMCID: PMC7582872 DOI: 10.3390/ijms21197298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 12/31/2022] Open
Abstract
Synapses play a central role for the processing of information in the brain and have been analyzed in countless biochemical, electrophysiological, imaging, and computational studies. The functionality and plasticity of synapses are nevertheless still difficult to predict, and conflicting hypotheses have been proposed for many synaptic processes. In this review, we argue that the cause of these problems is a lack of understanding of the spatiotemporal dynamics of key synaptic components. Fortunately, a number of emerging imaging approaches, going beyond super-resolution, should be able to provide required protein positions in space at different points in time. Mathematical models can then integrate the resulting information to allow the prediction of the spatiotemporal dynamics. We argue that these models, to deal with the complexity of synaptic processes, need to be designed in a sufficiently abstract way. Taken together, we suggest that a well-designed combination of imaging and modelling approaches will result in a far more complete understanding of synaptic function than currently possible.
Collapse
|
31
|
Lucidi M, Hristu R, Nichele L, Stanciu GA, Tranca DE, Holban AM, Visca P, Stanciu SG, Cincotti G. STED nanoscopy of KK114-stained pathogenic bacteria. JOURNAL OF BIOPHOTONICS 2020; 13:e202000097. [PMID: 32483852 DOI: 10.1002/jbio.202000097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/11/2020] [Accepted: 05/27/2020] [Indexed: 06/11/2023]
Abstract
Super-resolution microscopy techniques can provide answers to still pending questions on prokaryotic organisms but are yet to be used at their full potential for this purpose. To address this, we evaluate the ability of the rhodamine-like KK114 dye to label various types of bacteria, to enable imaging of fine structural details with stimulated emission depletion microscopy (STED). We assessed fluorescent labeling with KK114 for eleven Gram-positive and Gram-negative bacterial species and observed that this contrast agent binds to their cell membranes. Significant differences in the labeling outputs were noticed across the tested bacterial species, but importantly, KK114-staining allowed the observation of subtle nanometric cell details in some cases. For example, a helix pattern resembling a cytoskeleton arrangement was detected in Bacillus subtilis. Furthermore, we found that KK114 easily penetrates the membrane of bacterial microorganism that lost their viability, which can be useful to discriminate between living and dead cells.
Collapse
Affiliation(s)
| | - Radu Hristu
- Center for Microscopy - Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | | | - George A Stanciu
- Center for Microscopy - Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | - Denis E Tranca
- Center for Microscopy - Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | - Alina Maria Holban
- Microbiology and Immunology Department, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Paolo Visca
- Department of Sciences, University Roma Tre, Rome, Italy
| | - Stefan G Stanciu
- Center for Microscopy - Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | | |
Collapse
|
32
|
Iyer SS, Srivastava A. Degeneracy in molecular scale organization of biological membranes. SOFT MATTER 2020; 16:6752-6764. [PMID: 32628232 DOI: 10.1039/d0sm00619j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The scale-rich spatiotemporal organization in biological membranes has its origin in the differential inter- and intra-molecular interactions among their constituents. In this work, we explore the molecular-origin behind that variety and possible degeneracy in lateral organization in membranes. For our study, we post-process microsecond long all-atom molecular dynamics trajectories for three systems that exhibit fluid phase coexistence: (i) PSM/POPC/Chol (0.47/0.32/0.21), (ii) PSM/DOPC/Chol (0.43/0.38/0.19) and (iii) DPPC/DOPC/Chol (0.37/0.36/0.27). To distinguish the liquid ordered and disordered regions at molecular scales, we calculate the degree of non-affineness of individual lipids in their neighbourhood and track their topological rearrangements. Disconnectivity graph analysis with respect to membrane organization shows that the DPPC/DOPC/Chol and PSM/DOPC/Chol systems exhibit funnel-like energy landscapes as opposed to a highly frustrated energy landscape for the more biomimetic PSM/POPC/Chol system. We use these measurements to develop a continuous lattice Hamiltonian and evolve that using Monte Carlo simulated annealing to explore the possibility of structural degeneracy in membrane organization. Our data show that model membranes with lipid constituents that are biomimetic (PSM/POPC/Chol) have the ability to access a large range of membrane sub-structure space (higher degeneracy) as compared to the other two systems, which form only one kind of substructure even with changing composition. Since the spatiotemporal organization in biological membranes dictates the "molecular encounters" and in turn larger scale biological processes such as molecular transport, trafficking and cellular signalling, we posit that this structural degeneracy could enable access to a larger repository to functionally important molecular organization in systems with physiologically relevant compositions.
Collapse
Affiliation(s)
- Sahithya S Iyer
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.
| | | |
Collapse
|
33
|
Direct and indirect cholesterol effects on membrane proteins with special focus on potassium channels. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158706. [DOI: 10.1016/j.bbalip.2020.158706] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/19/2020] [Accepted: 03/30/2020] [Indexed: 12/16/2022]
|
34
|
Kiyoshi C, Tedeschi A. Axon growth and synaptic function: A balancing act for axonal regeneration and neuronal circuit formation in CNS trauma and disease. Dev Neurobiol 2020; 80:277-301. [PMID: 32902152 PMCID: PMC7754183 DOI: 10.1002/dneu.22780] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022]
Abstract
Axons in the adult mammalian central nervous system (CNS) fail to regenerate inside out due to intrinsic and extrinsic neuronal determinants. During CNS development, axon growth, synapse formation, and function are tightly regulated processes allowing immature neurons to effectively grow an axon, navigate toward target areas, form synaptic contacts and become part of information processing networks that control behavior in adulthood. Not only immature neurons are able to precisely control the expression of a plethora of genes necessary for axon extension and pathfinding, synapse formation and function, but also non-neuronal cells such as astrocytes and microglia actively participate in sculpting the nervous system through refinement, consolidation, and elimination of synaptic contacts. Recent evidence indicates that a balancing act between axon regeneration and synaptic function may be crucial for rebuilding functional neuronal circuits after CNS trauma and disease in adulthood. Here, we review the role of classical and new intrinsic and extrinsic neuronal determinants in the context of CNS development, injury, and disease. Moreover, we discuss strategies targeting neuronal and non-neuronal cell behaviors, either alone or in combination, to promote axon regeneration and neuronal circuit formation in adulthood.
Collapse
Affiliation(s)
- Conrad Kiyoshi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Andrea Tedeschi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
- Discovery Theme on Chronic Brain Injury, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
35
|
Löwe M, Kalacheva M, Boersma AJ, Kedrov A. The more the merrier: effects of macromolecular crowding on the structure and dynamics of biological membranes. FEBS J 2020; 287:5039-5067. [DOI: 10.1111/febs.15429] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 12/23/2022]
Affiliation(s)
- Maryna Löwe
- Synthetic Membrane Systems Institute of Biochemistry Heinrich Heine University Düsseldorf Germany
| | | | | | - Alexej Kedrov
- Synthetic Membrane Systems Institute of Biochemistry Heinrich Heine University Düsseldorf Germany
| |
Collapse
|
36
|
Salvage SC, Rees JS, McStea A, Hirsch M, Wang L, Tynan CJ, Reed MW, Irons JR, Butler R, Thompson AJ, Martin-Fernandez ML, Huang CL, Jackson AP. Supramolecular clustering of the cardiac sodium channel Nav1.5 in HEK293F cells, with and without the auxiliary β3-subunit. FASEB J 2020; 34:3537-3553. [PMID: 31950564 PMCID: PMC7079131 DOI: 10.1096/fj.201701473rr] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 09/30/2019] [Accepted: 10/08/2019] [Indexed: 01/24/2023]
Abstract
Voltage-gated sodium channels comprise an ion-selective α-subunit and one or more associated β-subunits. The β3-subunit (encoded by the SCN3B gene) is an important physiological regulator of the heart-specific sodium channel, Nav1.5. We have previously shown that when expressed alone in HEK293F cells, the full-length β3-subunit forms trimers in the plasma membrane. We extend this result with biochemical assays and use the proximity ligation assay (PLA) to identify oligomeric β3-subunits, not just at the plasma membrane, but throughout the secretory pathway. We then investigate the corresponding clustering properties of the α-subunit and the effects upon these of the β3-subunits. The oligomeric status of the Nav1.5 α-subunit in vivo, with or without the β3-subunit, has not been previously investigated. Using super-resolution fluorescence imaging, we show that under conditions typically used in electrophysiological studies, the Nav1.5 α-subunit assembles on the plasma membrane of HEK293F cells into spatially localized clusters rather than individual and randomly dispersed molecules. Quantitative analysis indicates that the β3-subunit is not required for this clustering but β3 does significantly change the distribution of cluster sizes and nearest-neighbor distances between Nav1.5 α-subunits. However, when assayed by PLA, the β3-subunit increases the number of PLA-positive signals generated by anti-(Nav1.5 α-subunit) antibodies, mainly at the plasma membrane. Since PLA can be sensitive to the orientation of proteins within a cluster, we suggest that the β3-subunit introduces a significant change in the relative alignment of individual Nav1.5 α-subunits, but the clustering itself depends on other factors. We also show that these structural and higher-order changes induced by the β3-subunit do not alter the degree of electrophysiological gating cooperativity between Nav1.5 α-subunits. Our data provide new insights into the role of the β3-subunit and the supramolecular organization of sodium channels, in an important model cell system that is widely used to study Nav channel behavior.
Collapse
Affiliation(s)
| | | | - Alexandra McStea
- Central Laser FacilityResearch Complex at HarwellScience and Technology Facilities CouncilRutherford Appleton LaboratoryOxfordUK
| | - Michael Hirsch
- Central Laser FacilityResearch Complex at HarwellScience and Technology Facilities CouncilRutherford Appleton LaboratoryOxfordUK
| | - Lin Wang
- Central Laser FacilityResearch Complex at HarwellScience and Technology Facilities CouncilRutherford Appleton LaboratoryOxfordUK
| | - Christopher J. Tynan
- Central Laser FacilityResearch Complex at HarwellScience and Technology Facilities CouncilRutherford Appleton LaboratoryOxfordUK
| | - Matthew W. Reed
- Department of Nuclear PhysicsResearch School of Physics and EngineeringAustralian National UniversityCanberrraACTAustralia
| | | | - Richard Butler
- Wellcome Trust/Cancer Research UK Gurdon InstituteUniversity of CambridgeCambridgeUK
| | | | - Marisa L. Martin-Fernandez
- Central Laser FacilityResearch Complex at HarwellScience and Technology Facilities CouncilRutherford Appleton LaboratoryOxfordUK
| | - Christopher L.‐H. Huang
- Deparment of BiochemistryUniversity of CambridgeCambridgeUK
- Department of Physiology, Development and NeuroscienceUniversity of CambridgeCambridgeUK
| | | |
Collapse
|
37
|
Dynamics and Endocytosis of Flot1 in Arabidopsis Require CPI1 Function. Int J Mol Sci 2020; 21:ijms21051552. [PMID: 32106431 PMCID: PMC7084554 DOI: 10.3390/ijms21051552] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 01/15/2023] Open
Abstract
Membrane microdomains are nano-scale domains (10–200 nm) enriched in sterols and sphingolipids. They have many important biological functions, including vesicle transport, endocytosis, and pathogen invasion. A previous study reported that the membrane microdomain-associated protein Flotillin1 (Flot1) was involved in plant development in Arabidopsis thaliana; however, whether sterols affect the plant immunity conveyed by Flot1 is unknown. Here, we showed that the root length in sterol-deficient cyclopropylsterol isomerase 1 (cpi1-1) mutants expressing Flot1 was significantly shorter than in control seedlings. The cotyledon epidermal cells in cpi1-1 mutants expressing Flot1 were smaller than in controls. Moreover, variable-angle total internal reflection fluorescence microscopy (VA-TIRFM) and single-particle tracking (SPT) analysis demonstrated that the long-distance Flot1-GFP movement was decreased significantly in cpi1-1 mutants compared with the control seedlings. Meanwhile, the value of the diffusion coefficient Ĝ was dramatically decreased in cpi1-1 mutants after flagelin22 (flg22) treatment compared with the control seedlings, indicating that sterols affect the lateral mobility of Flot1-GFP within the plasma membrane. Importantly, using confocal microscopy, we determined that the endocytosis of Flot1-GFP was decreased in cpi1-1 mutants, which was confirmed by fluorescence cross spectroscopy (FCS) analysis. Hence, these results demonstrate that sterol composition plays a critical role in the plant defense responses of Flot1.
Collapse
|
38
|
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: 308] [Impact Index Per Article: 77.0] [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.
Collapse
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
| |
Collapse
|
39
|
Stanly TA, Fritzsche M, Banerji S, Shrestha D, Schneider F, Eggeling C, Jackson DG. The cortical actin network regulates avidity-dependent binding of hyaluronan by the lymphatic vessel endothelial receptor LYVE-1. J Biol Chem 2020; 295:5036-5050. [PMID: 32034091 PMCID: PMC7152780 DOI: 10.1074/jbc.ra119.011992] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/29/2020] [Indexed: 12/16/2022] Open
Abstract
Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) mediates the docking and entry of dendritic cells to lymphatic vessels through selective adhesion to its ligand hyaluronan in the leukocyte surface glycocalyx. To bind hyaluronan efficiently, LYVE-1 must undergo surface clustering, a process that is induced efficiently by the large cross-linked assemblages of glycosaminoglycan present within leukocyte pericellular matrices but is induced poorly by the shorter polymer alone. These properties suggested that LYVE-1 may have limited mobility in the endothelial plasma membrane, but no biophysical investigation of these parameters has been carried out to date. Here, using super-resolution fluorescence microscopy and spectroscopy combined with biochemical analyses of the receptor in primary lymphatic endothelial cells, we provide the first evidence that LYVE-1 dynamics are indeed restricted by the submembranous actin network. We show that actin disruption not only increases LYVE-1 lateral diffusion but also enhances hyaluronan-binding activity. However, unlike the related leukocyte HA receptor CD44, which uses ERM and ankyrin motifs within its cytoplasmic tail to bind actin, LYVE-1 displays little if any direct interaction with actin, as determined by co-immunoprecipitation. Instead, as shown by super-resolution stimulated emission depletion microscopy in combination with fluorescence correlation spectroscopy, LYVE-1 diffusion is restricted by transient entrapment within submembranous actin corrals. These results point to an actin-mediated constraint on LYVE-1 clustering in lymphatic endothelium that tunes the receptor for selective engagement with hyaluronan assemblages in the glycocalyx that are large enough to cross-bridge the corral-bound LYVE-1 molecules and thereby facilitate leukocyte adhesion and transmigration.
Collapse
Affiliation(s)
- Tess A Stanly
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom.,York Biomedical Research Institute, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Marco Fritzsche
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom.,Kennedy Institute for Rheumatology, University of Oxford, Oxford OX3 7FY, United Kingdom
| | - Suneale Banerji
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Dilip Shrestha
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Falk Schneider
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Christian Eggeling
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom .,Wolfson Imaging Centre, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Applied Optics and Biophysics, Friedrich-Schiller-University Jena, Max-Wien Platz 4, 07743 Jena, Germany
| | - David G Jackson
- Medical Research Council Human Immunology Unit, University of Oxford, Oxford OX3 9DS, United Kingdom
| |
Collapse
|
40
|
Petit JD, Li ZP, Nicolas WJ, Grison MS, Bayer EM. Dare to change, the dynamics behind plasmodesmata-mediated cell-to-cell communication. CURRENT OPINION IN PLANT BIOLOGY 2020; 53:80-89. [PMID: 31805513 DOI: 10.1016/j.pbi.2019.10.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/18/2019] [Accepted: 10/21/2019] [Indexed: 06/10/2023]
Abstract
Plasmodesmata pores control the entry and exit of molecules at cell-to-cell boundaries. Hundreds of pores perforate the plant cell wall, connecting cells together and establishing direct cytosolic and membrane continuity. This ability to connect cells in such a way is a hallmark of plant physiology and is thought to have allowed sessile multicellularity in Plantae kingdom. Indeed, plasmodesmata-mediated cell-to-cell signalling is fundamental to many plant-related processes. In fact, there are so many facets of plant biology under the control of plasmodesmata that it is hard to conceive how such tiny structures can do so much. While they provide 'open doors' between cells, they also need to guarantee cellular identities and territories by selectively transporting molecules. Although plasmodesmata operating mode remains difficult to grasp, little by little plant scientists are divulging their secrets. In this review, we highlight novel functions of cell-to-cell signalling and share recent insights into how plasmodesmata structural and molecular signatures confer functional specificity and plasticity to these unique cellular machines.
Collapse
Affiliation(s)
- Jules D Petit
- Laboratoire de Biogenèse Membranaire, UMR5200 CNRS, Université de Bordeaux, Villenave d'Ornon, France; Laboratoire de Biophysique Moléculaire aux Interfaces, TERRA Research Centre, GX ABT, Université de Liège, Gembloux, Belgium
| | - Ziqiang Patrick Li
- Laboratoire de Biogenèse Membranaire, UMR5200 CNRS, Université de Bordeaux, Villenave d'Ornon, France
| | - William J Nicolas
- Laboratoire de Biogenèse Membranaire, UMR5200 CNRS, Université de Bordeaux, Villenave d'Ornon, France
| | - Magali S Grison
- Laboratoire de Biogenèse Membranaire, UMR5200 CNRS, Université de Bordeaux, Villenave d'Ornon, France
| | - Emmanuelle M Bayer
- Laboratoire de Biogenèse Membranaire, UMR5200 CNRS, Université de Bordeaux, Villenave d'Ornon, France.
| |
Collapse
|
41
|
Wilson KA, Wang L, MacDermott-Opeskin H, O'Mara ML. The Fats of Life: Using Computational Chemistry to Characterise the Eukaryotic Cell Membrane. Aust J Chem 2020. [DOI: 10.1071/ch19353] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Our current knowledge of the structural dynamics and complexity of lipid bilayers is still developing. Computational techniques, especially molecular dynamics simulations, have increased our understanding significantly as they allow us to model functions that cannot currently be experimentally resolved. Here we review available computational tools and techniques, the role of the major lipid species, insights gained into lipid bilayer structure and function from molecular dynamics simulations, and recent progress towards the computational modelling of the physiological complexity of eukaryotic lipid bilayers.
Collapse
|
42
|
Liao YH, Lin CH, Cheng CY, Wong WC, Juo JY, Hsieh CL. Monovalent and Oriented Labeling of Gold Nanoprobes for the High-Resolution Tracking of a Single-Membrane Molecule. ACS NANO 2019; 13:10918-10928. [PMID: 31259529 DOI: 10.1021/acsnano.9b01176] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Single-molecule tracking is a powerful method to study molecular dynamics in living systems including biological membranes. High-resolution single-molecule tracking requires a bright and stable signal, which has typically been facilitated by nanoparticles due to their superb optical properties. However, there are concerns about using a nanoparticle to label a single molecule because of its relatively large size and the possibility of cross-linking multiple target molecules, both of which could affect the original molecular dynamics. In this work, using various labeling schemes, we investigate the effects using nanoparticles to measure the diffusion of single-membrane molecules. By conjugating a low density of streptavidin (sAv) to gold nanoparticles (AuNPs) of different sizes (10, 15, 20, 30, and 40 nm), we isolate and quantify the effect of the particle size on the diffusion of biotinylated lipids in supported lipid bilayers (SLBs). We find that single sAv tends to cross-link two biotinylated lipids, leading to a much slower diffusion in SLBs. We further demonstrate a simple and robust strategy for the monovalent and oriented labeling of a single lipid molecule with a AuNP by using naturally dimeric rhizavidin (rAv) as a bridge, thus connecting the biotinylated nanoparticle surface and biotinylated target molecule. The rAv-AuNP conjugate demonstrates fast and free diffusion in SLBs (2-3 μm2/s for rAv-AuNP sizes of 10-40 nm), which is comparable to the diffusion of dye-labeled lipids, indicating that the adverse size and cross-linking effects are successfully avoided. We also note that the diffusion of dye-labeled lipids critically depends on the choice of dye, which could report different diffusion coefficients by about 20% (2.2 μm2/s of ATTO647N and 2.6 μm2/s of ATTO532). By comparing the diffusion of the uniformly and randomly oriented labeling of a single lipid molecule with a AuNP, we conclude that oriented labeling is favorable for measuring the diffusion of single-membrane molecules. Our work shows that the measured diffusion of the membrane molecule is highly sensitive to the molecular design of the cross-linker for labeling. The demonstrated approach of monovalent and oriented AuNP labeling provides the opportunity to study single-molecule membrane dynamics at much higher spatiotemporal resolutions and, most importantly, without labeling artifacts.
Collapse
Affiliation(s)
- Yi-Hung Liao
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| | - Chih-Hsiang Lin
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| | - Ching-Ya Cheng
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| | - Wai Cheng Wong
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| | - Jz-Yuan Juo
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| | - Chia-Lung Hsieh
- Institute of Atomic and Molecular Sciences (IAMS) , Academia Sinica , Taipei 10617 , Taiwan
| |
Collapse
|
43
|
Goiko M, de Bruyn JR, Heit B. Membrane Diffusion Occurs by Continuous-Time Random Walk Sustained by Vesicular Trafficking. Biophys J 2019; 114:2887-2899. [PMID: 29925025 DOI: 10.1016/j.bpj.2018.04.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 03/06/2018] [Accepted: 04/16/2018] [Indexed: 10/28/2022] Open
Abstract
Diffusion in cellular membranes is regulated by processes that occur over a range of spatial and temporal scales. These processes include membrane fluidity, interprotein and interlipid interactions, interactions with membrane microdomains, interactions with the underlying cytoskeleton, and cellular processes that result in net membrane movement. The complex, non-Brownian diffusion that results from these processes has been difficult to characterize, and moreover, the impact of factors such as membrane recycling on membrane diffusion remains largely unexplored. We have used a careful statistical analysis of single-particle tracking data of the single-pass plasma membrane protein CD93 to show that the diffusion of this protein is well described by a continuous-time random walk in parallel with an aging process mediated by membrane corrals. The overall result is an evolution in the diffusion of CD93: proteins initially diffuse freely on the cell surface but over time become increasingly trapped within diffusion-limiting membrane corrals. Stable populations of freely diffusing and corralled CD93 are maintained by an endocytic/exocytic process in which corralled CD93 is selectively endocytosed, whereas freely diffusing CD93 is replenished by exocytosis of newly synthesized and recycled CD93. This trafficking not only maintained CD93 diffusivity but also maintained the heterogeneous distribution of CD93 in the plasma membrane. These results provide insight into the nature of the biological and biophysical processes that can lead to significantly non-Brownian diffusion of membrane proteins and demonstrate that ongoing membrane recycling is critical to maintaining steady-state diffusion and distribution of proteins in the plasma membrane.
Collapse
Affiliation(s)
- Maria Goiko
- Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada; Department of Physics and Astronomy, The University of Western Ontario, London, Ontario, Canada
| | - John R de Bruyn
- Department of Physics and Astronomy, The University of Western Ontario, London, Ontario, Canada
| | - Bryan Heit
- Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada; Centre for Human Immunology, The University of Western Ontario, London, Ontario, Canada.
| |
Collapse
|
44
|
Membrane Dynamics in Health and Disease: Impact on Cellular Signalling. J Membr Biol 2019; 252:213-226. [PMID: 31435696 DOI: 10.1007/s00232-019-00087-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/07/2019] [Indexed: 12/16/2022]
Abstract
Biological membranes display a staggering complexity of lipids and proteins orchestrating cellular functions. Superior analytical tools coupled with numerous functional cellular screens have enabled us to query their role in cellular signalling, trafficking, guiding protein structure and function-all of which rely on the dynamic membrane lipid properties indispensable for proper cellular functions. Alteration of these has led to emergence of various pathological conditions, thus opening an area of lipid-centric therapeutic approaches. This perspective is a short summary of the dynamic properties of membranes essential for proper cellular functions, dictating both protein and lipid functions, and mis-regulated in diseases. Towards the end, we focus on some challenges lying ahead and potential means to tackle the same, mainly underscored by multi-disciplinary approaches.
Collapse
|
45
|
Janáček J, Brejchová J, Svoboda P. Determination of δ-opioid receptor molecules mobility in living cells plasma membrane by novel method of FRAP analysis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1346-1354. [PMID: 31071299 DOI: 10.1016/j.bbamem.2019.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 04/09/2019] [Accepted: 04/29/2019] [Indexed: 11/18/2022]
Abstract
Fluorescence recovery after photobleaching (FRAP) is the preferred method for analyzing the lateral mobility of fluorescently-tagged proteins in the plasma membranes (PMs) of live cells. FRAP experiments are described as being easy to perform; however, the analysis of the acquired data can be difficult. The evaluation procedure must be properly combined with the imaging setup of the confocal microscope to provide unbiased results. With the aim of increasing the accuracy of determining the diffusion coefficient (D) and mobile fraction (Mf) of PM proteins, we developed a novel method for FRAP analysis in the equatorial plane of the cell. This method is based on the calculation of photobleaching characteristics, derived from the light intensity profile and optical parameters of the confocal microscope, and on the model of fluorescent molecule diffusion in PM regions outside of the focal plane. Furthermore, cell movement artifacts in the FRAP data are ameliorated by using a region of interest, which is not fixed but instead moves adaptively in coordination with the movement of cells. When this method was used to determine the mobility of the δ-opioid receptor-eYFP in HEK293 cells, a highly significant decrease in receptor mobility was detected in cholesterol-depleted cells. This decrease was fully reversible by the replenishment of cholesterol levels. Our results demonstrate the crucial role played by cholesterol in the dynamic organization of δ-opioid receptors in the PM under in vivo conditions. Our method may be applied for the determination of the D and Mf values of other PM proteins.
Collapse
Affiliation(s)
- Jiří Janáček
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic.
| | - Jana Brejchová
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic
| | - Petr Svoboda
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic
| |
Collapse
|
46
|
Richter KN, Patzelt C, Phan NTN, Rizzoli SO. Antibody-driven capture of synaptic vesicle proteins on the plasma membrane enables the analysis of their interactions with other synaptic proteins. Sci Rep 2019; 9:9231. [PMID: 31239503 PMCID: PMC6592915 DOI: 10.1038/s41598-019-45729-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 06/13/2019] [Indexed: 01/07/2023] Open
Abstract
Many organelles from the secretory pathway fuse to the plasma membrane, to exocytose different cargoes. Their proteins are then retrieved from the plasma membrane by endocytosis, and the organelles are re-formed. It is generally unclear whether the organelle proteins colocalize when they are on the plasma membrane, or whether they disperse. To address this, we generated here a new approach, which we tested on synaptic vesicles, organelles that are known to exo- and endocytose frequently. We tagged the synaptotagmin molecules of newly exocytosed vesicles using clusters of primary and secondary antibodies targeted against the luminal domains of these molecules. The antibody clusters are too large for endocytosis, and thus sequestered the synaptotagmin molecules on the plasma membrane. Immunostainings for other synaptic molecules then revealed whether they colocalized with the sequestered synaptotagmin molecules. We suggest that such assays may be in the future extended to other cell types and other organelles.
Collapse
Affiliation(s)
- Katharina N Richter
- Institute for Neuro- and Sensory Physiology, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany.
| | - Christina Patzelt
- Institute for Neuro- and Sensory Physiology, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
| | - Nhu T N Phan
- Institute for Neuro- and Sensory Physiology, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
| | - Silvio O Rizzoli
- Institute for Neuro- and Sensory Physiology, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany.
| |
Collapse
|
47
|
The cell wall regulates dynamics and size of plasma-membrane nanodomains in Arabidopsis. Proc Natl Acad Sci U S A 2019; 116:12857-12862. [PMID: 31182605 PMCID: PMC6601011 DOI: 10.1073/pnas.1819077116] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Plant plasma-membrane (PM) proteins are involved in several vital processes, such as detection of pathogens, solute transport, and cellular signaling. For these proteins to function effectively there needs to be structure within the PM allowing, for example, proteins in the same signaling cascade to be spatially organized. Here we demonstrate that several proteins with divergent functions are located in clusters of differing size in the membrane using subdiffraction-limited Airyscan confocal microscopy. Single particle tracking reveals that these proteins move at different rates within the membrane. Actin and microtubule cytoskeletons appear to significantly regulate the mobility of one of these proteins (the pathogen receptor FLS2) and we further demonstrate that the cell wall is critical for the regulation of cluster size by quantifying single particle dynamics of proteins with key roles in morphogenesis (PIN3) and pathogen perception (FLS2). We propose a model in which the cell wall and cytoskeleton are pivotal for regulation of protein cluster size and dynamics, thereby contributing to the formation and functionality of membrane nanodomains.
Collapse
|
48
|
Marrink SJ, Corradi V, Souza PC, Ingólfsson HI, Tieleman DP, Sansom MS. Computational Modeling of Realistic Cell Membranes. Chem Rev 2019; 119:6184-6226. [PMID: 30623647 PMCID: PMC6509646 DOI: 10.1021/acs.chemrev.8b00460] [Citation(s) in RCA: 419] [Impact Index Per Article: 83.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Indexed: 12/15/2022]
Abstract
Cell membranes contain a large variety of lipid types and are crowded with proteins, endowing them with the plasticity needed to fulfill their key roles in cell functioning. The compositional complexity of cellular membranes gives rise to a heterogeneous lateral organization, which is still poorly understood. Computational models, in particular molecular dynamics simulations and related techniques, have provided important insight into the organizational principles of cell membranes over the past decades. Now, we are witnessing a transition from simulations of simpler membrane models to multicomponent systems, culminating in realistic models of an increasing variety of cell types and organelles. Here, we review the state of the art in the field of realistic membrane simulations and discuss the current limitations and challenges ahead.
Collapse
Affiliation(s)
- Siewert J. Marrink
- Groningen
Biomolecular Sciences and Biotechnology Institute & Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Valentina Corradi
- Centre
for Molecular Simulation and Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Paulo C.T. Souza
- Groningen
Biomolecular Sciences and Biotechnology Institute & Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Helgi I. Ingólfsson
- Biosciences
and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - D. Peter Tieleman
- Centre
for Molecular Simulation and Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Mark S.P. Sansom
- Department
of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K.
| |
Collapse
|
49
|
Pereira PM, Albrecht D, Culley S, Jacobs C, Marsh M, Mercer J, Henriques R. Fix Your Membrane Receptor Imaging: Actin Cytoskeleton and CD4 Membrane Organization Disruption by Chemical Fixation. Front Immunol 2019; 10:675. [PMID: 31024536 PMCID: PMC6460894 DOI: 10.3389/fimmu.2019.00675] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/12/2019] [Indexed: 12/25/2022] Open
Abstract
Single-molecule localization microscopy (SMLM) techniques allow near molecular scale resolution (~ 20 nm) as well as precise and robust analysis of protein organization at different scales. SMLM hardware, analytics and probes have been the focus of a variety of studies and are now commonly used in laboratories across the world. Protocol reliability and artifact identification are increasingly seen as important aspects of super-resolution microscopy. The reliability of these approaches thus requires in-depth evaluation so that biological findings are based on solid foundations. Here we explore how different fixation approaches that disrupt or preserve the actin cytoskeleton affect membrane protein organization. Using CD4 as a model, we show that fixation-mediated disruption of the actin cytoskeleton correlates with changes in CD4 membrane organization. We highlight how these artifacts are easy to overlook and how careful sample preparation is essential for extracting meaningful results from super-resolution microscopy.
Collapse
Affiliation(s)
- Pedro M. Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
| | - David Albrecht
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Siân Culley
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Caron Jacobs
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Mark Marsh
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Jason Mercer
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| |
Collapse
|
50
|
Padmanabhan P, Bademosi AT, Kasula R, Lauwers E, Verstreken P, Meunier FA. Need for speed: Super-resolving the dynamic nanoclustering of syntaxin-1 at exocytic fusion sites. Neuropharmacology 2019; 169:107554. [PMID: 30826343 DOI: 10.1016/j.neuropharm.2019.02.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/21/2019] [Accepted: 02/27/2019] [Indexed: 01/08/2023]
Abstract
Communication between cells relies on regulated exocytosis, a multi-step process that involves the docking, priming and fusion of vesicles with the plasma membrane, culminating in the release of neurotransmitters and hormones. Key proteins and lipids involved in exocytosis are subjected to Brownian movement and constantly switch between distinct motion states which are governed by short-lived molecular interactions. Critical biochemical reactions between exocytic proteins that occur in the confinement of nanodomains underpin the precise sequence of priming steps which leads to the fusion of vesicles. The advent of super-resolution microscopy techniques has provided the means to visualize individual molecules on the plasma membrane with high spatiotemporal resolution in live cells. These techniques are revealing a highly dynamic nature of the nanoscale organization of the exocytic machinery. In this review, we focus on soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) syntaxin-1, which mediates vesicular fusion. Syntaxin-1 is highly mobile at the plasma membrane, and its inherent speed allows fast assembly and disassembly of syntaxin-1 nanoclusters which are associated with exocytosis. We reflect on recent studies which have revealed the mechanisms regulating syntaxin-1 nanoclustering on the plasma membrane and draw inferences on the effect of synaptic activity, phosphoinositides, N-ethylmaleimide-sensitive factor (NSF), α-soluble NSF attachment protein (α-SNAP) and SNARE complex assembly on the dynamic nanoscale organization of syntaxin-1. This article is part of the special issue entitled 'Mobility and trafficking of neuronal membrane proteins'.
Collapse
Affiliation(s)
- Pranesh Padmanabhan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland, Australia
| | - Adekunle T Bademosi
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland, Australia
| | - Ravikiran Kasula
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland, Australia
| | - Elsa Lauwers
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Patrik Verstreken
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland, Australia.
| |
Collapse
|