1
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Obara CJ, Nixon-Abell J, Moore AS, Riccio F, Hoffman DP, Shtengel G, Xu CS, Schaefer K, Pasolli HA, Masson JB, Hess HF, Calderon CP, Blackstone C, Lippincott-Schwartz J. Motion of VAPB molecules reveals ER-mitochondria contact site subdomains. Nature 2024; 626:169-176. [PMID: 38267577 PMCID: PMC10830423 DOI: 10.1038/s41586-023-06956-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 12/08/2023] [Indexed: 01/26/2024]
Abstract
To coordinate cellular physiology, eukaryotic cells rely on the rapid exchange of molecules at specialized organelle-organelle contact sites1,2. Endoplasmic reticulum-mitochondrial contact sites (ERMCSs) are particularly vital communication hubs, playing key roles in the exchange of signalling molecules, lipids and metabolites3,4. ERMCSs are maintained by interactions between complementary tethering molecules on the surface of each organelle5,6. However, due to the extreme sensitivity of these membrane interfaces to experimental perturbation7,8, a clear understanding of their nanoscale organization and regulation is still lacking. Here we combine three-dimensional electron microscopy with high-speed molecular tracking of a model organelle tether, Vesicle-associated membrane protein (VAMP)-associated protein B (VAPB), to map the structure and diffusion landscape of ERMCSs. We uncovered dynamic subdomains within VAPB contact sites that correlate with ER membrane curvature and undergo rapid remodelling. We show that VAPB molecules enter and leave ERMCSs within seconds, despite the contact site itself remaining stable over much longer time scales. This metastability allows ERMCSs to remodel with changes in the physiological environment to accommodate metabolic needs of the cell. An amyotrophic lateral sclerosis-associated mutation in VAPB perturbs these subdomains, likely impairing their remodelling capacity and resulting in impaired interorganelle communication. These results establish high-speed single-molecule imaging as a new tool for mapping the structure of contact site interfaces and reveal that the diffusion landscape of VAPB at contact sites is a crucial component of ERMCS homeostasis.
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Affiliation(s)
| | - Jonathon Nixon-Abell
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
- Cambridge Institute for Medical Research (CIMR), Cambridge, UK
| | - Andrew S Moore
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Federica Riccio
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
- Centre for Gene Therapy & Regenerative Medicine, King's College London, London, UK
| | - David P Hoffman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
- 10x Genomics, Pleasanton, CA, USA
| | - Gleb Shtengel
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - C Shan Xu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Kathy Schaefer
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - H Amalia Pasolli
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jean-Baptiste Masson
- Decision and Bayesian Computation, Neuroscience, & Computational Biology Departments, CNRS UMR 3751, Institut Pasteur, Université de Paris, Paris, France
| | - Harald F Hess
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Christopher P Calderon
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO, USA
- Ursa Analytics, Inc., Denver, CO, USA
| | - Craig Blackstone
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
- MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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2
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Okamoto K, Fujita H, Okada Y, Shinkai S, Onami S, Abe K, Fujimoto K, Sasaki K, Shioi G, Watanabe TM. Single-molecule tracking of Nanog and Oct4 in living mouse embryonic stem cells uncovers a feedback mechanism of pluripotency maintenance. EMBO J 2023; 42:e112305. [PMID: 37609947 PMCID: PMC10505915 DOI: 10.15252/embj.2022112305] [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: 08/05/2022] [Revised: 06/13/2023] [Accepted: 06/22/2023] [Indexed: 08/24/2023] Open
Abstract
Nanog and Oct4 are core transcription factors that form part of a gene regulatory network to regulate hundreds of target genes for pluripotency maintenance in mouse embryonic stem cells (ESCs). To understand their function in the pluripotency maintenance, we visualised and quantified the dynamics of single molecules of Nanog and Oct4 in a mouse ESCs during pluripotency loss. Interestingly, Nanog interacted longer with its target loci upon reduced expression or at the onset of differentiation, suggesting a feedback mechanism to maintain the pluripotent state. The expression level and interaction time of Nanog and Oct4 correlate with their fluctuation and interaction frequency, respectively, which in turn depend on the ESC differentiation status. The DNA viscoelasticity near the Oct4 target locus remained flexible during differentiation, supporting its role either in chromatin opening or a preferred binding to uncondensed chromatin regions. Based on these results, we propose a new negative feedback mechanism for pluripotency maintenance via the DNA condensation state-dependent interplay of Nanog and Oct4.
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Affiliation(s)
- Kazuko Okamoto
- Laboratory for Comprehensive BioimagingRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
- Amphibian Research CenterHiroshima UniversityHiroshimaJapan
| | - Hideaki Fujita
- Department of Stem Cell Biology, Research Institute for Radiation Biology and MedicineHiroshima UniversityHigashi‐HiroshimaJapan
| | - Yasushi Okada
- Laboratory for Cell Polarity RegulationRIKEN Center for Biosystems Dynamics Research (BDR)OsakaJapan
- Department of Cell BiologyGraduate School of Medicine, The University of TokyoTokyoJapan
- Department of PhysicsUniversal Biology Institute (UBI)Graduate School of Science, The University of TokyoTokyoJapan
- International Research Center for Neurointelligence (WPI‐IRCN)Institutes for Advanced Study, The University of TokyoTokyoJapan
| | - Soya Shinkai
- Laboratory for Developmental DynamicsRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
- Research Center for the Mathematics on Chromatin Live Dynamics (RcMcD)Hiroshima UniversityHiroshimaJapan
| | - Shuichi Onami
- Laboratory for Developmental DynamicsRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
| | - Kuniya Abe
- Technology and Development Team for Mammalian Genome DynamicsRIKEN BioResource Research Center (BRC)TsukubaJapan
| | - Kenta Fujimoto
- Department of Stem Cell Biology, Research Institute for Radiation Biology and MedicineHiroshima UniversityHigashi‐HiroshimaJapan
| | - Kensuke Sasaki
- Laboratory for Comprehensive BioimagingRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
| | - Go Shioi
- Laboratory for Comprehensive BioimagingRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
| | - Tomonobu M Watanabe
- Laboratory for Comprehensive BioimagingRIKEN Center for Biosystems Dynamics Research (BDR)KobeJapan
- Department of Stem Cell Biology, Research Institute for Radiation Biology and MedicineHiroshima UniversityHigashi‐HiroshimaJapan
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3
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Paupiah AL, Marques X, Merlaud Z, Russeau M, Levi S, Renner M. Introducing Diinamic, a flexible and robust method for clustering analysis in single-molecule localization microscopy. BIOLOGICAL IMAGING 2023; 3:e14. [PMID: 38487695 PMCID: PMC10936397 DOI: 10.1017/s2633903x23000156] [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: 01/26/2023] [Revised: 05/26/2023] [Accepted: 06/22/2023] [Indexed: 03/17/2024]
Abstract
Super-resolution microscopy allowed major improvements in our capacity to describe and explain biological organization at the nanoscale. Single-molecule localization microscopy (SMLM) uses the positions of molecules to create super-resolved images, but it can also provide new insights into the organization of molecules through appropriate pointillistic analyses that fully exploit the sparse nature of SMLM data. However, the main drawback of SMLM is the lack of analytical tools easily applicable to the diverse types of data that can arise from biological samples. Typically, a cloud of detections may be a cluster of molecules or not depending on the local density of detections, but also on the size of molecules themselves, the labeling technique, the photo-physics of the fluorophore, and the imaging conditions. We aimed to set an easy-to-use clustering analysis protocol adaptable to different types of data. Here, we introduce Diinamic, which combines different density-based analyses and optional thresholding to facilitate the detection of clusters. On simulated or real SMLM data, Diinamic correctly identified clusters of different sizes and densities, being performant even in noisy datasets with multiple detections per fluorophore. It also detected subdomains ("nanodomains") in clusters with non-homogeneous distribution of detections.
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Affiliation(s)
- Anne-Lise Paupiah
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
| | - Xavier Marques
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
- Museum National d’Histoire Naturelle, CNRS UMR 7196-INSERM U1154, Paris, France
| | - Zaha Merlaud
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
| | - Marion Russeau
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
| | - Sabine Levi
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
| | - Marianne Renner
- Inserm UMR-S 1270, Paris, France
- Sorbonne Université, Paris, France
- Institut du Fer à Moulin, INSERM-Sorbonne Université, Paris, France
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4
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Abstract
Super-resolution fluorescence microscopy allows the investigation of cellular structures at nanoscale resolution using light. Current developments in super-resolution microscopy have focused on reliable quantification of the underlying biological data. In this review, we first describe the basic principles of super-resolution microscopy techniques such as stimulated emission depletion (STED) microscopy and single-molecule localization microscopy (SMLM), and then give a broad overview of methodological developments to quantify super-resolution data, particularly those geared toward SMLM data. We cover commonly used techniques such as spatial point pattern analysis, colocalization, and protein copy number quantification but also describe more advanced techniques such as structural modeling, single-particle tracking, and biosensing. Finally, we provide an outlook on exciting new research directions to which quantitative super-resolution microscopy might be applied.
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Affiliation(s)
- Siewert Hugelier
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , ,
| | - P L Colosi
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , ,
| | - Melike Lakadamyali
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , ,
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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5
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Wakefield DL, Golfetto O, Jorand R, Biswas S, Meyer K, Avery KN, Zer C, Cacao EE, Tobin SJ, Talisman IJ, Williams JC, Jovanovic-Talisman T. Using quantitative single molecule localization microscopy to optimize multivalent HER2-targeting ligands. Front Med (Lausanne) 2023; 10:1064242. [PMID: 37138747 PMCID: PMC10149953 DOI: 10.3389/fmed.2023.1064242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 03/30/2023] [Indexed: 05/05/2023] Open
Abstract
Introduction The progression-free survival of patients with HER2-positive metastatic breast cancer is significantly extended by a combination of two monoclonal antibodies, trastuzumab and pertuzumab, which target independent epitopes of the extracellular domain of HER2. The improved efficacy of the combination over individual antibody therapies targeting HER2 is still being investigated, and several molecular mechanisms may be in play: the combination downregulates HER2, improves antibody-dependent cell mediated cytotoxicity, and/or affects the organization of surface-expressed antigens, which may attenuate downstream signaling. Methods By combining protein engineering and quantitative single molecule localization microscopy (qSMLM), here we both assessed and optimized clustering of HER2 in cultured breast cancer cells. Results We detected marked changes to the cellular membrane organization of HER2 when cells were treated with therapeutic antibodies. When we compared untreated samples to four treatment scenarios, we observed the following HER2 membrane features: (1) the monovalent Fab domain of trastuzumab did not significantly affect HER2 clustering; (2) individual therapy with either trastuzumab or (3) pertuzumab produced significantly higher levels of HER2 clustering; (4) a combination of trastuzumab plus pertuzumab produced the highest level of HER2 clustering. To further enhance this last effect, we created multivalent ligands using meditope technology. Treatment with a tetravalent meditope ligand combined with meditope-enabled trastuzumab resulted in pronounced HER2 clustering. Moreover, compared to pertuzumab plus trastuzumab, at early time points this meditope-based combination was more effective at inhibiting epidermal growth factor (EGF) dependent activation of several downstream protein kinases. Discussion Collectively, mAbs and multivalent ligands can efficiently alter the organization and activation of the HER2 receptors. We expect this approach could be used in the future to develop new therapeutics.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - John C. Williams
- Department of Cancer Biology and Molecular Medicine, Beckman Research Institute, Duarte, CA, United States
| | - Tijana Jovanovic-Talisman
- Department of Cancer Biology and Molecular Medicine, Beckman Research Institute, Duarte, CA, United States
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6
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Guzikowski NJ, Kavalali ET. Super-resolution imaging of synaptic scaffold proteins in rat hippocampal neurons. STAR Protoc 2023; 4:102080. [PMID: 36853692 PMCID: PMC9932186 DOI: 10.1016/j.xpro.2023.102080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/13/2022] [Accepted: 01/13/2023] [Indexed: 02/05/2023] Open
Abstract
Visualizing the nano-organization of the synapse is fundamental to elucidating the structure-function relationship of the nervous system. The advent of super-resolution microscopy provides a tool to assess and quantify the dynamic organization of numerous proteins at the synapse. Here we present a protocol assessing inhibitory synapse scaffold protein, gephyrin, in rat primary hippocampal cultures using dSTORM microscopy. We delineate the steps for artemisinin treatment, immunocytochemistry, dSTORM image acquisition, single-molecule localization, and the analysis of synaptic scaffold protein dynamics. For complete details on the use and execution of this protocol, please refer to Guzikowski and Kavalali (2022).1.
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Affiliation(s)
- Natalie J Guzikowski
- Department of Pharmacology and Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA.
| | - Ege T Kavalali
- Department of Pharmacology and Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA.
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7
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Shemonti AS, Plebani E, Biscola NP, Jaffey DM, Havton LA, Keast JR, Pothen A, Dundar MM, Powley TL, Rajwa B. A novel statistical methodology for quantifying the spatial arrangements of axons in peripheral nerves. Front Neurosci 2023; 17:1072779. [PMID: 36968498 PMCID: PMC10034020 DOI: 10.3389/fnins.2023.1072779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 02/09/2023] [Indexed: 03/11/2023] Open
Abstract
A thorough understanding of the neuroanatomy of peripheral nerves is required for a better insight into their function and the development of neuromodulation tools and strategies. In biophysical modeling, it is commonly assumed that the complex spatial arrangement of myelinated and unmyelinated axons in peripheral nerves is random, however, in reality the axonal organization is inhomogeneous and anisotropic. Present quantitative neuroanatomy methods analyze peripheral nerves in terms of the number of axons and the morphometric characteristics of the axons, such as area and diameter. In this study, we employed spatial statistics and point process models to describe the spatial arrangement of axons and Sinkhorn distances to compute the similarities between these arrangements (in terms of first- and second-order statistics) in various vagus and pelvic nerve cross-sections. We utilized high-resolution transmission electron microscopy (TEM) images that have been segmented using a custom-built high-throughput deep learning system based on a highly modified U-Net architecture. Our findings show a novel and innovative approach to quantifying similarities between spatial point patterns using metrics derived from the solution to the optimal transport problem. We also present a generalizable pipeline for quantitative analysis of peripheral nerve architecture. Our data demonstrate differences between male- and female-originating samples and similarities between the pelvic and abdominal vagus nerves.
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Affiliation(s)
| | - Emanuele Plebani
- Department of Computer & Information Sciences, Indiana University - Purdue University Indianapolis, Indianapolis, IN, United States
| | - Natalia P. Biscola
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Deborah M. Jaffey
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
| | - Leif A. Havton
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY, United States
| | - Janet R. Keast
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC, Australia
| | - Alex Pothen
- Department of Computer Science, Purdue University, West Lafayette, IN, United States
| | - M. Murat Dundar
- Department of Computer & Information Sciences, Indiana University - Purdue University Indianapolis, Indianapolis, IN, United States
| | - Terry L. Powley
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
| | - Bartek Rajwa
- Bindley Bioscience Center, Purdue University, West Lafayette, IN, United States
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8
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Yuan Z, Hansen SB. Cholesterol Regulation of Membrane Proteins Revealed by Two-Color Super-Resolution Imaging. MEMBRANES 2023; 13:membranes13020250. [PMID: 36837753 PMCID: PMC9966874 DOI: 10.3390/membranes13020250] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/05/2023] [Accepted: 02/07/2023] [Indexed: 05/15/2023]
Abstract
Cholesterol and phosphatidyl inositol 4,5-bisphosphate (PIP2) are hydrophobic molecules that regulate protein function in the plasma membrane of all cells. In this review, we discuss how changes in cholesterol concentration cause nanoscopic (<200 nm) movements of membrane proteins to regulate their function. Cholesterol is known to cluster many membrane proteins (often palmitoylated proteins) with long-chain saturated lipids. Although PIP2 is better known for gating ion channels, in this review, we will discuss a second independent function as a regulator of nanoscopic protein movement that opposes cholesterol clustering. The understanding of the movement of proteins between nanoscopic lipid domains emerged largely through the recent advent of super-resolution imaging and the establishment of two-color techniques to label lipids separate from proteins. We discuss the labeling techniques for imaging, their strengths and weakness, and how they are used to reveal novel mechanisms for an ion channel, transporter, and enzyme function. Among the mechanisms, we describe substrate and ligand presentation and their ability to activate enzymes, gate channels, and transporters rapidly and potently. Finally, we define cholesterol-regulated proteins (CRP) and discuss the role of PIP2 in opposing the regulation of cholesterol, as seen through super-resolution imaging.
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Affiliation(s)
- Zixuan Yuan
- Department of Molecular Medicine, Department of Neuroscience, UF Scripps, Jupiter, FL 33458, USA
- Department of Neuroscience UF Scripps, Jupiter, FL 33458, USA
- Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Scott B. Hansen
- Department of Molecular Medicine, Department of Neuroscience, UF Scripps, Jupiter, FL 33458, USA
- Department of Neuroscience UF Scripps, Jupiter, FL 33458, USA
- Correspondence:
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9
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Scalisi S, Ahmad A, D'Annunzio S, Rousseau D, Zippo A. Quantitative Analysis of PcG-Associated Condensates by Stochastic Optical Reconstruction Microscopy (STORM). Methods Mol Biol 2023; 2655:183-200. [PMID: 37212997 DOI: 10.1007/978-1-0716-3143-0_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The polycomb group (PcG) proteins play a central role in the maintenance of a repressive state of gene expression. Recent findings demonstrate that PcG components are organized into nuclear condensates, contributing to the reshaping of chromatin architecture in physiological and pathological conditions, thus affecting the nuclear mechanics. In this context, direct stochastic optical reconstruction microscopy (dSTORM) provides an effective tool to achieve a detailed characterization of PcG condensates by visualizing them at a nanometric level. Furthermore, by analyzing dSTORM datasets with cluster analysis algorithms, quantitative information can be yielded regarding protein numbers, grouping, and spatial organization. Here, we describe how to set up a dSTORM experiment and perform the data analysis to study PcG complexes' components in adhesion cells quantitatively.
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Affiliation(s)
- Silvia Scalisi
- Chromatin Biology & Epigenetics Lab, Department of Cellular, Computational, and Integrative Biology (CIBIO), University of Trento, Trento, Italy
| | - Ali Ahmad
- Laboratoire Angevin de Recherche en Ingénierie des Systèmes, UMR INRAE IRHS, Université d'Angers, Angers, France
| | - Sarah D'Annunzio
- Chromatin Biology & Epigenetics Lab, Department of Cellular, Computational, and Integrative Biology (CIBIO), University of Trento, Trento, Italy
| | - David Rousseau
- Laboratoire Angevin de Recherche en Ingénierie des Systèmes, UMR INRAE IRHS, Université d'Angers, Angers, France
| | - Alessio Zippo
- Chromatin Biology & Epigenetics Lab, Department of Cellular, Computational, and Integrative Biology (CIBIO), University of Trento, Trento, Italy.
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10
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Etheridge TJ, Carr AM, Herbert AD. GDSC SMLM: Single-molecule localisation microscopy software for ImageJ. Wellcome Open Res 2022; 7:241. [PMID: 37351368 PMCID: PMC10282564 DOI: 10.12688/wellcomeopenres.18327.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2022] [Indexed: 08/03/2023] Open
Abstract
Single-molecule localisation microscopy (SMLM) uses software to extract super-resolved positions from microscope images of fluorescent molecules. These localisations can then be used to render super-resolution images or analysed to extract information about molecular behaviour. The GDSC SMLM software provides a set of tools for analysing SMLM data in a single cross-platform environment. The software identifies fluorescent molecules in raw microscope images and localises their positions using stages of spot detection, spot fitting and spot rejection. The resulting localisation data set can then be visualised, cropped and filtered. A suite of downstream analysis tools enable the user to perform single-particle tracking, cluster analysis and drift correction. In addition, GDSC SMLM also provides utility tools that enable modelling of EM-CCD and sCMOS cameras as well as point spread functions (PSFs) for data simulation. The software is written in Java and runs as a collection of plugins for the ImageJ software.
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Affiliation(s)
- Thomas J. Etheridge
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, BN1 9RQ, UK
| | - Antony M. Carr
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, BN1 9RQ, UK
| | - Alex D. Herbert
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, BN1 9RQ, UK
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11
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Milstein JN, Nino DF, Zhou X, Gradinaru CC. Single-molecule counting applied to the study of GPCR oligomerization. Biophys J 2022; 121:3175-3187. [PMID: 35927960 PMCID: PMC9463696 DOI: 10.1016/j.bpj.2022.07.034] [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: 05/31/2022] [Revised: 06/29/2022] [Accepted: 07/28/2022] [Indexed: 11/24/2022] Open
Abstract
Single-molecule counting techniques enable a precise determination of the intracellular abundance and stoichiometry of proteins and macromolecular complexes. These details are often challenging to quantitatively assess yet are essential for our understanding of cellular function. Consider G-protein-coupled receptors-an expansive class of transmembrane signaling proteins that participate in many vital physiological functions making them a popular target for drug development. While early evidence for the role of oligomerization in receptor signaling came from ensemble biochemical and biophysical assays, innovations in single-molecule measurements are now driving a paradigm shift in our understanding of its relevance. Here, we review recent developments in single-molecule counting with a focus on photobleaching step counting and the emerging technique of quantitative single-molecule localization microscopy-with a particular emphasis on the potential for these techniques to advance our understanding of the role of oligomerization in G-protein-coupled receptor signaling.
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Affiliation(s)
- Joshua N Milstein
- Department of Physics, University of Toronto, Toronto, Ontario, Canada; Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada.
| | - Daniel F Nino
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Xiaohan Zhou
- Department of Physics, University of Toronto, Toronto, Ontario, Canada; Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Claudiu C Gradinaru
- Department of Physics, University of Toronto, Toronto, Ontario, Canada; Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada.
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12
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Guzikowski NJ, Kavalali ET. Nano-organization of spontaneous GABAergic transmission directs its autonomous function in neuronal signaling. Cell Rep 2022; 40:111172. [PMID: 35947950 PMCID: PMC9392417 DOI: 10.1016/j.celrep.2022.111172] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 04/12/2022] [Accepted: 07/15/2022] [Indexed: 01/04/2023] Open
Abstract
Earlier studies delineated the precise arrangement of proteins that drive neurotransmitter release and postsynaptic signaling at excitatory synapses. However, spatial organization of neurotransmission at inhibitory synapses remains unclear. Here, we took advantage of the molecularly specific interaction of antimalarial artemisinins and the inhibitory synapse scaffold protein, gephyrin, to probe the functional organization of gamma-aminobutyric acid A receptor (GABAAR)-mediated neurotransmission in central synapses. Short-term application of artemisinins severely contracts the size and density of gephyrin and GABAaR γ2 subunit clusters. This size contraction elicits a neuronal activity-independent increase in Bdnf expression due to a specific reduction in GABAergic spontaneous, but not evoked, neurotransmission. The same functional effect could be mimicked by disruption of microtubules that link gephyrin to the neuronal cytoskeleton. These results suggest that the GABAergic postsynaptic apparatus possesses a concentric center-surround organization, where the periphery of gephyrin clusters selectively maintains spontaneous GABAergic neurotransmission facilitating its autonomous function regulating Bdnf expression.
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Affiliation(s)
- Natalie J. Guzikowski
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37240-7933, USA,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37240-7933, USA
| | - Ege T. Kavalali
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37240-7933, USA,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37240-7933, USA,Lead contact,Correspondence:
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13
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Cappellari MV, Marcano-García LF, Simoncelli S, Aramendía PF. Determination of association equilibrium constant from single molecule fluorescence localization microscopy. Photochem Photobiol Sci 2022; 21:1751-1760. [PMID: 35749053 DOI: 10.1007/s43630-022-00254-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 05/31/2022] [Indexed: 11/26/2022]
Abstract
Single molecule fluorescence localization microscopy provides molecular localization with a precision in the tens of nanometer range in the plane perpendicular to the light propagation. This opens the possibility to count molecules and correlate their locations, starting from a map of the actual positions in a single molecule super resolution image. Considering molecular pair correlation as an indication of interaction, and a way to discern them from free molecules, we describe a method to calculate thermodynamic equilibrium constants. In this work, we use as a test system two complementary homo-oligonucleotides, one strand marked with Cyanine 3.5 and the other with Alexa Fluor 647. Hybridization is controlled by the amount of each strand, temperature, and the ionic force, and measured in steady state emission. The same samples are examined in Stochastic Optical Reconstruction Microscopy (STORM) experiments with split-field simultaneous two-colour detection. The effect of multiblinking, labelling-detection efficiency, and determination of the critical distance for association are discussed. We consistently determine values in STORM coincident with those of the bulk experiment.
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Affiliation(s)
- M Victoria Cappellari
- Centro de Investigaciones en Bionanociencias -''Elizabeth Jares-Erijman'' (CIBION), CONICET, Godoy Cruz 2390, 1425, Ciudad de Buenos Aires, Argentina
| | - Luis F Marcano-García
- Centro de Investigaciones en Bionanociencias -''Elizabeth Jares-Erijman'' (CIBION), CONICET, Godoy Cruz 2390, 1425, Ciudad de Buenos Aires, Argentina
| | - Sabrina Simoncelli
- London Centre for Nanotechnology and Department of Chemistry, University College London, London, WC1H 0AH, UK
| | - Pedro F Aramendía
- Centro de Investigaciones en Bionanociencias -''Elizabeth Jares-Erijman'' (CIBION), CONICET, Godoy Cruz 2390, 1425, Ciudad de Buenos Aires, Argentina.
- Departamento de Química Inorgánica, Analítica y Química Física. Facultad de Ciencias Exactas Y Naturales, Universidad de Buenos Aires, 1428, Ciudad de Buenos Aires, Argentina.
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14
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Maddox AL, Brehove MS, Eliato KR, Saftics A, Romano E, Press MF, Mortimer J, Jones V, Schmolze D, Seewaldt VL, Jovanovic-Talisman T. Molecular Assessment of HER2 to Identify Signatures Associated with Therapy Response in HER2-Positive Breast Cancer. Cancers (Basel) 2022; 14:cancers14112795. [PMID: 35681773 PMCID: PMC9179327 DOI: 10.3390/cancers14112795] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/29/2022] [Accepted: 06/01/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary The HER2 status of breast cancers is accurately determined by measuring HER2 protein overexpression and gene amplification. However, these clinical diagnostic tests cannot predict the response to therapy. Single molecule imaging approaches can quantify molecular features of HER2, such as receptor nano-organization, with exquisite spatial resolution and sensitivity. The aim of our study was to assess how the molecular features of HER2 varied with the therapy response. According to our results in cultured cell lines and six patient specimens, the therapy response was associated with high detected HER2 densities and clustering. This advanced imaging approach can thus provide key data to complement the current diagnostic standards. Abstract Trastuzumab, the prototype HER2-directed therapy, has markedly improved survival for women with HER2-positive breast cancers. However, only 40–60% of women with HER2-positive breast cancers achieve a complete pathological response to chemotherapy combined with HER2-directed therapy. The current diagnostic assays have poor positive-predictive accuracy in identifying therapy-responsive breast cancers. Here, we deployed quantitative single molecule localization microscopy to assess the molecular features of HER2 in a therapy-responsive setting. Using fluorescently labeled trastuzumab as a probe, we first compared the molecular features of HER2 in trastuzumab-sensitive (BT-474 and SK-BR-3) and trastuzumab-resistant (BT-474R and JIMT-1) cultured cell lines. Trastuzumab-sensitive cells had significantly higher detected HER2 densities and clustering. We then evaluated HER2 in pre-treatment core biopsies from women with breast cancer undergoing neoadjuvant therapy. A complete pathological response was associated with a high detected HER2 density and significant HER2 clustering. These results established the nano-organization of HER2 as a potential signature of therapy-responsive disease.
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Affiliation(s)
- Adam L. Maddox
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
| | - Matthew S. Brehove
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
| | - Kiarash R. Eliato
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
| | - Andras Saftics
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
| | - Eugenia Romano
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
| | - Michael F. Press
- Department of Pathology, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA;
| | - Joanne Mortimer
- Department of Medical Oncology, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA;
| | - Veronica Jones
- Department of Surgery, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA;
| | - Daniel Schmolze
- Department of Pathology, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA;
| | - Victoria L. Seewaldt
- Department of Population Sciences, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA;
| | - Tijana Jovanovic-Talisman
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA; (A.L.M.); (M.S.B.); (K.R.E.); (A.S.); (E.R.)
- Correspondence:
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15
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Cassaro CJ, Uphoff S. Super-Resolution Microscopy and Tracking of DNA-Binding Proteins in Bacterial Cells. Methods Mol Biol 2022; 2476:191-208. [PMID: 35635706 DOI: 10.1007/978-1-0716-2221-6_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The ability to detect individual fluorescent molecules inside living cells has enabled a range of powerful microscopy techniques that resolve biological processes on the molecular scale. These methods have also transformed the study of bacterial cell biology, which was previously obstructed by the limited spatial resolution of conventional microscopy. In the case of DNA-binding proteins, super-resolution microscopy can visualize the detailed spatial organization of DNA replication, transcription, and repair processes by reconstructing a map of single-molecule localizations. Furthermore, DNA-binding activities can be observed directly by tracking protein movement in real time. This allows identifying subpopulations of DNA-bound and diffusing proteins, and can be used to measure DNA-binding times in vivo. This chapter provides a detailed protocol for super-resolution microscopy and tracking of DNA-binding proteins in Escherichia coli cells. The protocol covers the genetic engineering and fluorescent labeling of strains and describes data acquisition and analysis procedures, such as super-resolution image reconstruction, mapping single-molecule tracks, computing diffusion coefficients to identify molecular subpopulations with different mobility, and analysis of DNA-binding kinetics. While the focus is on the study of bacterial chromosome biology, these approaches are generally applicable to other molecular processes and cell types.
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Affiliation(s)
- Chloé J Cassaro
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Stephan Uphoff
- Department of Biochemistry, University of Oxford, Oxford, UK.
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16
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Steindel M, Orsine de Almeida I, Strawbridge S, Chernova V, Holcman D, Ponjavic A, Basu S. Studying the Dynamics of Chromatin-Binding Proteins in Mammalian Cells Using Single-Molecule Localization Microscopy. Methods Mol Biol 2022; 2476:209-247. [PMID: 35635707 DOI: 10.1007/978-1-0716-2221-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Single-molecule localization microscopy (SMLM) allows the super-resolved imaging of proteins within mammalian nuclei at spatial resolutions comparable to that of a nucleosome itself (~20 nm). The technique is therefore well suited to the study of chromatin structure. Fixed-cell SMLM has already allowed temporal "snapshots" of how proteins are arranged on chromatin within mammalian nuclei. In this chapter, we focus on how recent developments, for example in selective plane illumination, 3D SMLM, and protein labeling, have led to a range of live-cell SMLM studies. We describe how to carry out single-particle tracking (SPT) of single proteins and, by analyzing their diffusion parameters, how to determine whether proteins interact with chromatin, diffuse freely, or do both. We can study the numbers of proteins that interact with chromatin and also determine their residence time on chromatin. We can determine whether these proteins form functional clusters within the nucleus as well as whether they form specific nuclear structures.
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Affiliation(s)
- Maike Steindel
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | | | - Stanley Strawbridge
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Valentyna Chernova
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - David Holcman
- Group of Computational Biology and Applied Mathematics, Institute of Biology, Ecole Normale Supérieure, Paris, France
| | - Aleks Ponjavic
- School of Physics and Astronomy and School of Food Science and Nutrition, University of Leeds, Leeds, UK.
| | - Srinjan Basu
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK.
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17
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Wakefield DL, Tobin SJ, Schmolze D, Jovanovic-Talisman T. Molecular Imaging of HER2 in Patient Tissues with Touch Prep-Quantitative Single Molecule Localization Microscopy. Methods Mol Biol 2022; 2394:231-248. [PMID: 35094332 PMCID: PMC9121336 DOI: 10.1007/978-1-0716-1811-0_15] [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] [Indexed: 01/03/2023]
Abstract
Biomolecules can be investigated at the nanoscale with quantitative single molecule localization microscopy (qSMLM). This technique, which achieves single molecule sensitivity, can probe how membrane receptors are organized under both normal and pathological conditions. While a number of receptors have been extensively studied in cultured cells, technical challenges have largely impeded their robust quantification in tissue samples. To rigorously interrogate tissue samples, methodological advancements are needed in three areas: analytical preparation of the sample, proper characterization of fluorescent reporters, and rapid/unbiased data analysis. Towards these ends, we have combined qSMLM with a touch preparation technique (touch prep-qSMLM). In this new method, touch prep is first used to obtain monolayers of patient cells. Then, highly selective, fluorescently labeled probes are used to detect the receptors of interest on the plasma membranes of cells. Finally, quantitative algorithms are used to analyze the imaging data. Using this touch prep-qSMLM methodology, we interrogated the density and nano-organization of human epidermal growth factor receptor 2 (HER2) in fresh breast cancer tissues. Touch prep-qSMLM agreed well with current clinical methods. Importantly, touch prep-qSMLM can be easily extended to other pathological conditions and ultimately used in precision medicine.
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Affiliation(s)
- Devin L Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, USA
- Amgen, South San Francisco, CA, USA
| | - Steven J Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, USA
| | - Daniel Schmolze
- Department of Pathology, City of Hope Comprehensive Cancer Center, Duarte, CA, USA
| | - Tijana Jovanovic-Talisman
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, USA.
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18
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Yan Q, Cai M, Jing Y, Li H, Xu H, Sun J, Gao J, Wang H. Quantitatively mapping the interaction of HER2 and EGFR on cell membranes with peptide probes. NANOSCALE 2021; 13:17629-17637. [PMID: 34664051 DOI: 10.1039/d1nr02684d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Human epidermal growth factor receptor-2 (HER2) is a member of the epidermal growth factor receptor (HER) family that is involved in various biological processes such as cell proliferation, survival, differentiation, migration and invasion. It generally functions in the form of homo-/hetero-dimers or oligomers with other HER family members. Although its essential roles in cellular activities have been widely recognized, questions concerning the spatial distribution of HER2 on the membranes and the interactions between it and other ErbB family members remain obscure. Here, we obtained a high-quality dSTORM image of HER2 nanoscale clusters recognized by peptide probes, and found that HER2 forms clusters containing different numbers of molecules on cell membranes. Moreover, we found that HER2 and EGFR formed hetero-oligomers on non-stimulated cell membranes, whereas EGF stimulation reduced the degree of heteromerization, suggesting that HER2 and EGFR hetero-oligomers may inhibit the activation of EGFR. Collectively, our work revealed the clustered distribution of HER2 and quantified the changes of the interaction between HER2 and EGFR in the resting and active states at the single molecular level, which promotes a deeper understanding of the protein-protein interaction on cell membranes.
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Affiliation(s)
- Qiuyan Yan
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
| | - Mingjun Cai
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
| | - Yingying Jing
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
| | - Hongru Li
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
- University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Haijiao Xu
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
| | - Jiayin Sun
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
| | - Jing Gao
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
- University of Science and Technology of China, Hefei, Anhui 230027, China
- Laboratory for Marine Biology and Biotechnology, Qing Dao National Laboratory for Marine Science and Technology, Wenhai Road, Aoshanwei, Jimo, Qingdao, Shandong, 266237, China
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19
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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.
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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
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20
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Ghosh S, Feigelson SW, Montresor A, Shimoni E, Roncato F, Legler DF, Laudanna C, Haran G, Alon R. CCR7 signalosomes are preassembled on tips of lymphocyte microvilli in proximity to LFA-1. Biophys J 2021; 120:4002-4012. [PMID: 34411577 DOI: 10.1016/j.bpj.2021.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/27/2021] [Accepted: 08/11/2021] [Indexed: 10/20/2022] Open
Abstract
Leukocyte microvilli are elastic actin-rich projections implicated in rapid sensing and penetration across glycocalyx barriers. Microvilli are critical for the capture and arrest of flowing lymphocytes by high endothelial venules, the main lymph node portal vessels. T lymphocyte arrest involves subsecond activation of the integrin LFA-1 by the G-protein-coupled receptor CCR7 and its endothelial-displayed ligands, the chemokines CCL21 and CCL19. The topographical distribution of CCR7 and of LFA-1 in relation to lymphocyte microvilli has never been elucidated. We applied the recently developed microvillar cartography imaging technique to determine the topographical distribution of CCR7 and LFA-1 with respect to microvilli on peripheral blood T lymphocytes. We found that CCR7 is clustered on the tips of T cell microvilli. The vast majority of LFA-1 molecules were found on the cell body, likely assembled in macroclusters, but a subset of LFA-1, 5% of the total, were found scattered within 20 nm from the CCR7 clusters, implicating these LFA-1 molecules as targets for inside-out activation signals transmitted within a fraction of a second by chemokine-bound CCR7. Indeed, RhoA, the key GTPase involved in rapid LFA-1 affinity triggering by CCR7, was also found to be clustered near CCR7. In addition, we observed that the tyrosine kinase JAK2 controls CCR7-mediated LFA-1 affinity triggering and is also highly enriched on tips of microvilli. We propose that tips of lymphocyte microvilli are novel signalosomes for subsecond CCR7-mediated inside-out signaling to neighboring LFA-1 molecules, a critical checkpoint in LFA-1-mediated lymphocyte arrest on high endothelial venules.
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Affiliation(s)
- Shirsendu Ghosh
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Sara W Feigelson
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | | | - Eyal Shimoni
- Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Francesco Roncato
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Daniel F Legler
- Biotechnology Institute Thurgau, University of Konstanz, Kreuzlingen, Switzerland
| | - Carlo Laudanna
- Department of Medicine, University of Verona, Verona, Italy
| | - Gilad Haran
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel.
| | - Ronen Alon
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
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21
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Haas KT, Peaucelle A. Protocol for multicolor three-dimensional dSTORM data analysis using MATLAB-based script package Grafeo. STAR Protoc 2021; 2:100808. [PMID: 34541556 PMCID: PMC8437824 DOI: 10.1016/j.xpro.2021.100808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
This protocol describes the step-by-step analysis of the multicolor (one-, two-, or three-color) two- and three-dimensional dSTORM (direct STochastic Optical Reconstruction Microscopy) data using MATLAB-based script package Grafeo. Grafeo primarily uses pointillist data visualization and analysis frameworks, including the nearest neighbors, approach, Voronoi tessellation, Delaunay triangulation, Ripley’s (K, L) and two-point correlation functions, and graph-based clustering. For complete details on the use and execution of this protocol, please refer to Peaucelle et al. (2020), Haas et al., 2018, Haas et al. (2020b). Multicolor 3D dSTORM data visualization using scatter plots and Voronoi Diagrams Procedure for data filtering Spatial statistics, cluster, and colocalization analysis Graph-based cluster analysis with Delaunay triangulation
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Affiliation(s)
- Kalina Tamara Haas
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Alexis Peaucelle
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
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22
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Rapid statistical discrimination of fluorescence images of T cell receptors on immobilizing surfaces with different coating conditions. Sci Rep 2021; 11:15488. [PMID: 34326382 PMCID: PMC8322097 DOI: 10.1038/s41598-021-94730-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/15/2021] [Indexed: 11/24/2022] Open
Abstract
The spatial organization of T cell receptors (TCRs) correlates with membrane-associated signal amplification, dispersion, and regulation during T cell activation. Despite its potential clinical importance, quantitative analysis of the spatial arrangement of TCRs from standard fluorescence images remains difficult. Here, we report Statistical Classification Analyses of Membrane Protein Images or SCAMPI as a technique capable of analyzing the spatial arrangement of TCRs on the plasma membrane of T cells. We leveraged medical image analysis techniques that utilize pixel-based values. We transformed grayscale pixel values from fluorescence images of TCRs into estimated model parameters of partial differential equations. The estimated model parameters enabled an accurate classification using linear discrimination techniques, including Fisher Linear Discriminant (FLD) and Logistic Regression (LR). In a proof-of-principle study, we modeled and discriminated images of fluorescently tagged TCRs from Jurkat T cells on uncoated cover glass surfaces (Null) or coated cover glass surfaces with either positively charged poly-L-lysine (PLL) or TCR cross-linking anti-CD3 antibodies (OKT3). Using 80 training images and 20 test images per class, our statistical technique achieved 85% discrimination accuracy for both OKT3 versus PLL and OKT3 versus Null conditions. The run time of image data download, model construction, and image discrimination was 21.89 s on a laptop computer, comprised of 20.43 s for image data download, 1.30 s on the FLD-SCAMPI analysis, and 0.16 s on the LR-SCAMPI analysis. SCAMPI represents an alternative approach to morphology-based qualifications for discriminating complex patterns of membrane proteins conditioned on a small sample size and fast runtime. The technique paves pathways to characterize various physiological and pathological conditions using the spatial organization of TCRs from patient T cells.
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23
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He H, Liu L, Chen X, Wang Q, Wang X, Nau WM, Huang F. Carbon Dot Blinking Enables Accurate Molecular Counting at Nanoscale Resolution. Anal Chem 2021; 93:3968-3975. [DOI: 10.1021/acs.analchem.0c04885] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Hua He
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
| | - Lihua Liu
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
| | - Xiaoliang Chen
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
| | - Qian Wang
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
| | - Xiaojuan Wang
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
| | - Werner M. Nau
- Department of Life Sciences and Chemistry, Jacobs University Bremen, Campus Ring 1, Bremen 28759, Germany
| | - Fang Huang
- State Key Laboratory of Heavy Oil Processing and College of Chemical Engineering China, University of Petroleum (East China), Qingdao 266580, China
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24
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Peaucelle A, Wightman R, Haas KT. Multicolor 3D-dSTORM Reveals Native-State Ultrastructure of Polysaccharides' Network during Plant Cell Wall Assembly. iScience 2020; 23:101862. [PMID: 33336161 PMCID: PMC7733027 DOI: 10.1016/j.isci.2020.101862] [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: 07/29/2020] [Revised: 10/07/2020] [Accepted: 11/20/2020] [Indexed: 12/17/2022] Open
Abstract
The plant cell wall, a form of the extracellular matrix, is a complex and dynamic network of polymers mediating a plethora of physiological functions. How polysaccharides assemble into a coherent and heterogeneous matrix remains mostly undefined. Further progress requires improved molecular-level visualization methods that would gain a deeper understanding of the cell wall nanoarchitecture. dSTORM, a type of super-resolution microscopy, permits quantitative nanoimaging of the cell wall. However, due to the lack of single-cell model systems and the requirement of tissue-level imaging, its use in plant science is almost absent. Here we overcome these limitations; we compare two methods to achieve three-dimensional dSTORM and identify optimal photoswitching dyes for tissue-level multicolor nanoscopy. Combining dSTORM with spatial statistics, we reveal and characterize the ultrastructure of three major polysaccharides, callose, mannan, and cellulose, in the plant cell wall precursor and provide evidence for cellulose structural re-organization related to callose content.
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Affiliation(s)
- Alexis Peaucelle
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Raymond Wightman
- Microscopy Core Facility, Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, CB2 1LR, UK
| | - Kalina Tamara Haas
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
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25
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Lee H, Kang K, Mochizuki K, Lee C, Toh KA, Lee SA, Fujita K, Kim D. Surface Plasmon Localization-Based Super-resolved Raman Microscopy. NANO LETTERS 2020; 20:8951-8958. [PMID: 33186047 DOI: 10.1021/acs.nanolett.0c04219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate label-free measurement of molecular distribution by super-resolved Raman microscopy using surface plasmon (SP) localization. Localized SP was formed with plasmonic nanopost arrays (PNAs) for measurement of the molecular distribution in HeLa cells. Compared with conventional Raman microscopy on gold thin films, PNAs induce a localized near-field, which allows for the enhancement of the peak signal-to-noise ratio by as much as 4.5 dB in the Raman shifts. Super-resolved distributions of aromatic amino acids and lipids (C-C stretching and C-H2 twist mode) as targets in HeLa cells were obtained after image reconstruction. Results show almost 4-fold improvement on average in the lateral precision over conventional diffraction-limited Raman microscopy images. Combined with axial imaging in an evanescent field, the results suggest an improvement in optical resolution due to superlocalized light volume by more than an order of magnitude over that of conventional diffraction-limited Raman microscopy.
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Affiliation(s)
- Hongki Lee
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
| | - Kyungnam Kang
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
| | - Kentaro Mochizuki
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Changhun Lee
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
| | - Kar-Ann Toh
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
| | - Seung Ah Lee
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
| | - Katsumasa Fujita
- Department of Applied Physics, Osaka University, Osaka 565-0871, Japan
- Advanced Photonics and Biosensing Open Innovation Laboratory, AIST-Osaka University, Osaka 565-0871, Japan
- Transdimensional Life Imaging Division, Institute of Open and Transdisciplinary Research Initiatives, Osaka University, Osaka 565-0871, Japan
| | - Donghyun Kim
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea
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26
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Nino DF, Djayakarsana D, Milstein JN. FOCAL3D: A 3-dimensional clustering package for single-molecule localization microscopy. PLoS Comput Biol 2020; 16:e1008479. [PMID: 33290385 PMCID: PMC7748281 DOI: 10.1371/journal.pcbi.1008479] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/18/2020] [Accepted: 10/30/2020] [Indexed: 12/03/2022] Open
Abstract
Single-molecule localization microscopy (SMLM) is a powerful tool for studying intracellular structure and macromolecular organization at the nanoscale. The increasingly massive pointillistic data sets generated by SMLM require the development of new and highly efficient quantification tools. Here we present FOCAL3D, an accurate, flexible and exceedingly fast (scaling linearly with the number of localizations) density-based algorithm for quantifying spatial clustering in large 3D SMLM data sets. Unlike DBSCAN, which is perhaps the most commonly employed density-based clustering algorithm, an optimum set of parameters for FOCAL3D may be objectively determined. We initially validate the performance of FOCAL3D on simulated datasets at varying noise levels and for a range of cluster sizes. These simulated datasets are used to illustrate the parametric insensitivity of the algorithm, in contrast to DBSCAN, and clustering metrics such as the F1 and Silhouette score indicate that FOCAL3D is highly accurate, even in the presence of significant background noise and mixed populations of variable sized clusters, once optimized. We then apply FOCAL3D to 3D astigmatic dSTORM images of the nuclear pore complex (NPC) in human osteosaracoma cells, illustrating both the validity of the parameter optimization and the ability of the algorithm to accurately cluster complex, heterogeneous 3D clusters in a biological dataset. FOCAL3D is provided as an open source software package written in Python. We have developed an accurate, highly-efficient and flexible algorithm for quantifying spatial clustering in large, 3-dimensional single-molecule localization microscopy (SMLM) datasets. Our method, FOCAL3D, is provided as an open-source software package written in Python. FOCAL3D scales linearly with the number of localizations and the algorithmic parameters may be systematically optimized so that the resulting analysis is insensitive to variation over a range of parameter choices. We initially validate the performance and parametric insensitivity of FOCAL3D on simulated datasets, then apply the algorithm to 3-dimensional, astigmatic dSTORM images of the nuclear pore complex in human osteosarcoma cells.
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Affiliation(s)
- Daniel F. Nino
- Department of Physics, University of Toronto, Toronto, Ontario, Canada
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Daniel Djayakarsana
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Joshua N. Milstein
- Department of Physics, University of Toronto, Toronto, Ontario, Canada
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
- * E-mail:
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27
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Wang F, Liu Y, Zhang T, Gao J, Xu Y, Xie G, Zhao W, Wang H, Yang Y. Aging-associated changes in CD47 arrangement and interaction with thrombospondin-1 on red blood cells visualized by super-resolution imaging. Aging Cell 2020; 19:e13224. [PMID: 32866348 PMCID: PMC7576236 DOI: 10.1111/acel.13224] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/15/2022] Open
Abstract
CD47 serves as a ligand for signaling regulatory protein α (SIRPα) and as a receptor for thrombospondin-1 (TSP-1). Although CD47, TSP-1, and SIRPα are thought to be involved in the clearance of aged red blood cells (RBCs), aging-associated changes in the expression and interaction of these molecules on RBCs have been elusive. Using direct stochastic optical reconstruction microscopy (dSTORM)-based imaging and quantitative analysis, we can report that CD47 molecules on young RBCs reside as nanoclusters with little binding to TSP-1, suggesting a minimal role for TSP-1/CD47 signaling in normal RBCs. On aged RBCs, CD47 molecules decreased in number but formed bigger and denser clusters, with increased ability to bind TSP-1. Exposure of aged RBCs to TSP-1 resulted in a further increase in the size of CD47 clusters via a lipid raft-dependent mechanism. Furthermore, CD47 cluster formation was dramatically inhibited on thbs1-/- mouse RBCs and associated with a significantly prolonged RBC lifespan. These results indicate that the strength of CD47 binding to its ligand TSP-1 is predominantly determined by the distribution pattern and not the amount of CD47 molecules on RBCs, and offer direct evidence for the role of TSP-1 in phagocytosis of aged RBCs. This study provides clear nanoscale pictures of aging-associated changes in CD47 distribution and TSP-1/CD47 interaction on the cell surface, and insights into the molecular basis for how these molecules coordinate to remove aged RBCs.
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Affiliation(s)
- Feng Wang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
| | - Yan‐Hou Liu
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
| | - Ting Zhang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
| | - Jing Gao
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchunChina
| | - Yangyue Xu
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchunChina
| | - Guang‐Yao Xie
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
| | - Wen‐Jie Zhao
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
| | - Hongda Wang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchunChina
| | - Yong‐Guang Yang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationThe First HospitalInstitute of ImmunologyJilin UniversityChangchunChina
- National‐local Joint Engineering Laboratory of Animal Models for Human DiseasesChangchunChina
- International Center of Future ScienceJilin UniversityChangchunChina
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28
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Sun Y. Potential quality improvement of stochastic optical localization nanoscopy images obtained by frame by frame localization algorithms. Sci Rep 2020; 10:11844. [PMID: 32678167 PMCID: PMC7367355 DOI: 10.1038/s41598-020-68564-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 06/26/2020] [Indexed: 12/28/2022] Open
Abstract
A data movie of stochastic optical localization nanoscopy contains spatial and temporal correlations, both providing information of emitter locations. The majority of localization algorithms in the literature estimate emitter locations by frame-by-frame localization (FFL), which exploit only the spatial correlation and leave the temporal correlation into the FFL nanoscopy images. The temporal correlation contained in the FFL images, if exploited, can improve the localization accuracy and the image quality. In this paper, we analyze the properties of the FFL images in terms of root mean square minimum distance (RMSMD) and root mean square error (RMSE). It is shown that RMSMD and RMSE can be potentially reduced by a maximum fold equal to the square root of the average number of activations per emitter. Analyzed and revealed are also several statistical properties of RMSMD and RMSE and their relationship with respect to a large number of data frames, bias and variance of localization errors, small localization errors, sample drift, and the worst FFL image. Numerical examples are taken and the results confirm the prediction of analysis. The ideas about how to develop an algorithm to exploit the temporal correlation of FFL images are also briefly discussed. The results suggest development of two kinds of localization algorithms: the algorithms that can exploit the temporal correlation of FFL images and the unbiased localization algorithms.
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Affiliation(s)
- Yi Sun
- Electrical Engineering Department, Nanoscopy Laboratory, The City College of City University of New York, New York, NY, 10031, USA.
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29
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Abstract
Anesthetics are used every day in thousands of hospitals to induce loss of consciousness, yet scientists and the doctors who administer these compounds lack a molecular understanding for their action. The chemical properties of anesthetics suggest that they could target the plasma membrane. Here the authors show anesthetics directly target a subset of plasma membrane lipids to activate an ion channel in a two-step mechanism. Applying the mechanism, the authors mutate a fruit fly to be less sensitive to anesthetics and convert a nonanesthetic-sensitive channel into a sensitive one. These findings suggest a membrane-mediated mechanism will be an important consideration for other proteins of which direct binding of anesthetic has yet to explain conserved sensitivity to chemically diverse anesthetics. Inhaled anesthetics are a chemically diverse collection of hydrophobic molecules that robustly activate TWIK-related K+ channels (TREK-1) and reversibly induce loss of consciousness. For 100 y, anesthetics were speculated to target cellular membranes, yet no plausible mechanism emerged to explain a membrane effect on ion channels. Here we show that inhaled anesthetics (chloroform and isoflurane) activate TREK-1 through disruption of phospholipase D2 (PLD2) localization to lipid rafts and subsequent production of signaling lipid phosphatidic acid (PA). Catalytically dead PLD2 robustly blocks anesthetic TREK-1 currents in whole-cell patch-clamp recordings. Localization of PLD2 renders the TRAAK channel sensitive, a channel that is otherwise anesthetic insensitive. General anesthetics, such as chloroform, isoflurane, diethyl ether, xenon, and propofol, disrupt lipid rafts and activate PLD2. In the whole brain of flies, anesthesia disrupts rafts and PLDnull flies resist anesthesia. Our results establish a membrane-mediated target of inhaled anesthesia and suggest PA helps set thresholds of anesthetic sensitivity in vivo.
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30
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Szalai AM, Lopez LF, Morales-Vásquez MÁ, Stefani FD, Aramendía PF. Analysis of sparse molecular distributions in fibrous arrangements based on the distance to the first neighbor in single molecule localization microscopy. NANOSCALE 2020; 12:9495-9506. [PMID: 32313910 DOI: 10.1039/c9nr10805j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Single Molecule Localization Microscopy (SMLM) currently attains a lateral resolution of around 10 nm approaching molecular size. Together with increasingly specific fluorescent labeling, it opens the possibility to quantitatively analyze molecular organization. When the labeling density is high enough, SMLM provides clear images of the molecular organization. However, either due to limited labeling efficiency or due to intrinsically low molecular abundance, SMLM delivers a small set of sparse and highly precise localizations. In this work, we introduce a correlation analysis of molecular locations based on the functional dependence of the complementary cumulative distribution function (CCDF) of the distance to the first neighbor (r1). We demonstrate that the log(-log(CCDF(r1))) vs. log(r1) is characterized by a scaling exponent n that takes extreme values of 2 for a random 2D distribution and 1 for a strictly linear arrangement, and find that n is a robust and sensitive metric to distinguish characteristics of the underlying structure responsible for the molecular distribution, even at a very low labeling density. The method enables the detection of fibrillary organization and the estimation of the diameter of host fibers under conditions where a visual inspection provides no clue.
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Affiliation(s)
- Alan M Szalai
- Centro de Investigaciones en Bionanociencias "Elizabeth Jares-Erijman" (CIBION), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2390, C1425FQD Ciudad Autónoma de Buenos Aires, Argentina.
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31
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Fan Z, Kiosses WB, Sun H, Orecchioni M, Ghosheh Y, Zajonc DM, Arnaout MA, Gutierrez E, Groisman A, Ginsberg MH, Ley K. High-Affinity Bent β 2-Integrin Molecules in Arresting Neutrophils Face Each Other through Binding to ICAMs In cis. Cell Rep 2020; 26:119-130.e5. [PMID: 30605669 PMCID: PMC6625519 DOI: 10.1016/j.celrep.2018.12.038] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/09/2018] [Accepted: 12/07/2018] [Indexed: 01/13/2023] Open
Abstract
Leukocyte adhesion requires β2-integrin activation. Resting integrins exist in a bent-closed conformation-i.e., not extended (E-) and not high affinity (H-)-unable to bind ligand. Fully activated E+H+ integrin binds intercellular adhesion molecules (ICAMs) expressed on the opposing cell in trans. E-H- transitions to E+H+ through E+H- or through E-H+, which binds to ICAMs on the same cell in cis. Spatial patterning of activated integrins is thought to be required for effective arrest, but no high-resolution cell surface localization maps of activated integrins exist. Here, we developed Super-STORM by combining super-resolution microscopy with molecular modeling to precisely localize activated integrin molecules and identify the molecular patterns of activated integrins on primary human neutrophils. At the time of neutrophil arrest, E-H+ integrins face each other to form oriented (non-random) nanoclusters. To address the mechanism causing this pattern, we blocked integrin binding to ICAMs in cis, which significantly relieved the face-to-face orientation.
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Affiliation(s)
- Zhichao Fan
- Division of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - William Bill Kiosses
- Microscopy Core Facility, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Hao Sun
- Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Marco Orecchioni
- Division of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Yanal Ghosheh
- Division of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Dirk M Zajonc
- Division of Immune Regulation, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA; Department of Internal Medicine, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - M Amin Arnaout
- Harvard Medical School, Boston, MA 02115, USA; Leukocyte Biology and Inflammation Program, Massachusetts General Hospital, Boston, MA 02114, USA; Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Center for Regenerative Medicine, Medical Services, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Edgar Gutierrez
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Alex Groisman
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Mark H Ginsberg
- Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Klaus Ley
- Division of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA; Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
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32
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Petersen EN, Pavel MA, Wang H, Hansen SB. Disruption of palmitate-mediated localization; a shared pathway of force and anesthetic activation of TREK-1 channels. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2020; 1862:183091. [PMID: 31672538 PMCID: PMC6907892 DOI: 10.1016/j.bbamem.2019.183091] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/15/2019] [Accepted: 09/17/2019] [Indexed: 12/22/2022]
Abstract
TWIK related K+ channel (TREK-1) is a mechano- and anesthetic sensitive channel that when activated attenuates pain and causes anesthesia. Recently the enzyme phospholipase D2 (PLD2) was shown to bind to the channel and generate a local high concentration of phosphatidic acid (PA), an anionic signaling lipid that gates TREK-1. In a biological membrane, the cell harnesses lipid heterogeneity (lipid compartments) to control gating of TREK-1 using palmitate-mediated localization of PLD2. Here we discuss the ability of mechanical force and anesthetics to disrupt palmitate-mediated localization of PLD2 giving rise to TREK-1's mechano- and anesthetic-sensitive properties. The likely consequences of this indirect lipid-based mechanism of activation are discussed in terms of a putative model for excitatory and inhibitory mechano-effectors and anesthetic sensitive ion channels in a biological context. Lastly, we discuss the ability of locally generated PA to reach mM concentrations near TREK-1 and the biophysics of localized signaling. Palmitate-mediated localization of PLD2 emerges as a central control mechanism of TREK-1 responding to mechanical force and anesthetic action. This article is part of a Special Issue entitled: Molecular biophysics of membranes and membrane proteins.
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Affiliation(s)
- E Nicholas Petersen
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Mahmud Arif Pavel
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Hao Wang
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Scott B Hansen
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
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33
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Petazzi RA, Aji AK, Chiantia S. Fluorescence microscopy methods for the study of protein oligomerization. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 169:1-41. [DOI: 10.1016/bs.pmbts.2019.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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34
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Jing Y, Zhou L, Chen J, Xu H, Sun J, Cai M, Jiang J, Gao J, Wang H. Quantitatively Mapping the Assembly Pattern of EpCAM on Cell Membranes with Peptide Probes. Anal Chem 2019; 92:1865-1873. [DOI: 10.1021/acs.analchem.9b03901] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Yingying Jing
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
- University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Lulu Zhou
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Junling Chen
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Haijiao Xu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Jiayin Sun
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Mingjun Cai
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Junguang Jiang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Jing Gao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Research Center of Biomembranomics, Changchun, Jilin 130022, China
- University of Science and Technology of China, Hefei, Anhui 230027, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Wenhai Road, Aoshanwei, Jimo, Qingdao, Shandong 266237, China
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35
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Dietz MS, Heilemann M. Optical super-resolution microscopy unravels the molecular composition of functional protein complexes. NANOSCALE 2019; 11:17981-17991. [PMID: 31573593 DOI: 10.1039/c9nr06364a] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Optical super-resolution microscopy has revolutionized our understanding of cell biology. Next to visualizing cellular structures with near-molecular spatial resolution, an additional benefit is the molecular characterization of biomolecular complexes directly in an intact cell. Single-molecule localization microscopy, as one technology out of the toolbox of super-resolution methods, generates images by detecting the position of single fluorophore labels and is particularly suited for molecular quantification. We review imaging and analysis methods employing single-molecule localization microscopy and extract molecule numbers.
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Affiliation(s)
- Marina S Dietz
- Single Molecule Biophysics, Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany.
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36
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Development of PLGA nanoparticles for sustained release of a connexin43 mimetic peptide to target glioblastoma cells. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 108:110191. [PMID: 31923988 DOI: 10.1016/j.msec.2019.110191] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 01/01/2023]
Abstract
Effective therapeutic delivery of peptide and protein drugs is challenged by short in vivo half-lives due to rapid degradation. Sustained release formulations of αCT1, a 25 amino acid peptide drug, would afford lower dosing frequency in indications that require long term treatment, such as chronic wounds and cancers. In this study, rhodamine B (RhB) was used as a model drug to develop and optimize a double emulsion-solvent evaporation method of poly(lactic-co-glycolic acid) (PLGA) nanoparticle synthesis. Encapsulation of αCT1 in these nanoparticles (NPs) resulted in a sustained in vitro release profile over three weeks, characterized by an initial burst release of approximately 50% of total encapsulated drug over the first three days followed by sustained release over the remaining two and a half weeks. NP uptake by glioblastoma stem cells was through endocytosis and RhB and αCT1 were observed in cells after at least 4 days.
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37
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Robinson CV, Rohacs T, Hansen SB. Tools for Understanding Nanoscale Lipid Regulation of Ion Channels. Trends Biochem Sci 2019; 44:795-806. [PMID: 31060927 PMCID: PMC6729126 DOI: 10.1016/j.tibs.2019.04.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/23/2019] [Accepted: 04/01/2019] [Indexed: 11/17/2022]
Abstract
Anionic phospholipids are minor but prominent components of the plasma membrane that are necessary for ion channel function. Their persistence in bulk membranes, in particular phosphatidylinositol 4,5-bisphosphate (PIP2), initially suggested they act as channel cofactors. However, recent technologies have established an emerging system of nanoscale signaling to ion channels based on lipid compartmentalization (clustering), direct lipid binding, and local lipid dynamics that allow cells to harness lipid heterogeneity to gate ion channels. The new tools to study lipid binding are set to transform our view of the membrane and answer important questions surrounding ion channel-delimited processes such as mechanosensation.
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Affiliation(s)
- Carol V Robinson
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, UK
| | - Tibor Rohacs
- Department of Pharmacology, Physiology and Neuroscience, Rutgers New Jersey Medical School, Newark, NJ 07103, USA
| | - Scott B Hansen
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
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38
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Can single molecule localization microscopy detect nanoclusters in T cells? Curr Opin Chem Biol 2019; 51:130-137. [DOI: 10.1016/j.cbpa.2019.05.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 05/10/2019] [Accepted: 05/21/2019] [Indexed: 11/21/2022]
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39
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Smith EM, Gautier A, Puchner EM. Single-Molecule Localization Microscopy with the Fluorescence-Activating and Absorption-Shifting Tag (FAST) System. ACS Chem Biol 2019; 14:1115-1120. [PMID: 31083964 PMCID: PMC8608280 DOI: 10.1021/acschembio.9b00149] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We develop and employ the Fluorescence-Activating and absorption-Shifting Tag (FAST) system for super-resolution (SR) imaging and single-molecule tracking based on single-molecule localizations. The fast off rate of fluorogen binding, combined with its spatially well-separated labeling of the densely expressed FAST fusion proteins, allowed single-molecule measurements to be performed in both living and fixed cells. The well-separated fluorescence localization density was achieved by either reversibly controlling the fluorogen concentration or by irreversibly photobleaching the FAST-fluorogen complex. The experimentally determined resolution of 28 nm allowed us to resolve Ensconsin-labeled microtubules and to track single molecules in mitochondria. Our results demonstrate that FAST is well-suited for single-molecule localization microscopy (SMLM). The small size and the availability of spectrally distinct fluorogens present unique advantages of the FAST system as a potential orthogonal labeling strategy that could be applied in conjunction with existing super-resolution dyes and photoactivatable proteins in versatile imaging applications.
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Affiliation(s)
- Elizabeth M. Smith
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455
| | - Arnaud Gautier
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Elias M. Puchner
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455
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40
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Banaz N, Mäkelä J, Uphoff S. Choosing the right label for single-molecule tracking in live bacteria: side-by-side comparison of photoactivatable fluorescent protein and Halo tag dyes. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2019; 52:064002. [PMID: 30799881 PMCID: PMC6372142 DOI: 10.1088/1361-6463/aaf255] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 11/07/2018] [Accepted: 11/20/2018] [Indexed: 05/21/2023]
Abstract
Visualizing and quantifying molecular motion and interactions inside living cells provides crucial insight into the mechanisms underlying cell function. This has been achieved by super-resolution localization microscopy and single-molecule tracking in conjunction with photoactivatable fluorescent proteins (PA-FPs). An alternative labelling approach relies on genetically-encoded protein tags with cell-permeable fluorescent ligands which are brighter and less prone to photobleaching than fluorescent proteins but require a laborious labelling process. Either labelling method is associated with significant advantages and disadvantages that should be taken into consideration depending on the microscopy experiment planned. Here, we describe an optimised procedure for labelling Halo-tagged proteins in live Escherichia coli cells. We provide a side-by-side comparison of Halo tag with different fluorescent ligands against the popular photoactivatable fluorescent protein PAmCherry. Using test proteins with different intracellular dynamics, we evaluated fluorescence intensity, background, photostability, and results from single-molecule localization and tracking experiments. Capitalising on the brightness and extended spectral range of fluorescent Halo ligands, we also demonstrate high-speed and dual-colour single-molecule tracking.
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Affiliation(s)
- Nehir Banaz
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Jarno Mäkelä
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Stephan Uphoff
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
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41
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Tobin SJ, Wakefield DL, Terenius L, Vukojević V, Jovanović-Talisman T. Ethanol and Naltrexone Have Distinct Effects on the Lateral Nano-organization of Mu and Kappa Opioid Receptors in the Plasma Membrane. ACS Chem Neurosci 2019; 10:667-676. [PMID: 30418735 DOI: 10.1021/acschemneuro.8b00488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The complex spatiotemporal organization of proteins and lipids in the plasma membrane is an important determinant of receptor function. Certain substances, such as ethanol, can penetrate into the hydrophobic regions of the plasma membrane. By altering protein-lipid and protein-protein interactions, these substances can modify the dynamic lateral organization and the function of plasma membrane receptors. To assess changes in plasma membrane receptor organization, we used photoactivated localization microscopy (PALM). This single molecule localization microscopy technique was employed to quantitatively characterize the effects of pharmacologically relevant concentrations of ethanol and naltrexone (an opioid receptor antagonist and medication used to treat alcohol use disorders) on the lateral nano-organization of mu and kappa opioid receptors (MOR and KOR, respectively). Ethanol affected the lateral organization of MOR and KOR similarly: It reduced the size and occupancy of opioid receptor nanodomains and increased the fraction of opioid receptors residing outside of nanodomains. In contrast, naltrexone affected MOR and KOR lateral organization differently. It significantly increased KOR surface density, nanodomain size, and the occupancy of KOR nanodomains. However, naltrexone marginally affected these parameters for MOR. Pretreatment with naltrexone largely protected against ethanol-induced changes in MOR and KOR lateral organization. Based on these data, we propose a putative mechanism of naltrexone action that operates in addition to its canonical antagonistic effect on MOR- and KOR-mediated signaling.
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Affiliation(s)
- Steven J. Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
| | - Devin L. Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
| | - Lars Terenius
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm 17176, Sweden
| | - Vladana Vukojević
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm 17176, Sweden
| | - Tijana Jovanović-Talisman
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, California 91010, United States
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42
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Tobin SJ, Wakefield DL, Jones V, Liu X, Schmolze D, Jovanović-Talisman T. Single molecule localization microscopy coupled with touch preparation for the quantification of trastuzumab-bound HER2. Sci Rep 2018; 8:15154. [PMID: 30310083 PMCID: PMC6181918 DOI: 10.1038/s41598-018-33225-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 09/25/2018] [Indexed: 12/11/2022] Open
Abstract
All breast cancers are assessed for levels of human epidermal growth factor receptor 2 (HER2). Fluorescence in situ hybridization (FISH) and immunohistochemistry are currently used to determine if a patient is eligible for anti-HER2 therapy. Limitations of both tests include variability and relatively long processing times. Additionally, neither test determines whether HER2 contains the extracellular domain. While truncated in some tumors, this domain is required for binding of the therapeutic antibody trastuzumab. Here, trastuzumab was used to directly detect HER2 with quantitative single molecule localization microscopy (qSMLM). In proof of concept studies, our new method rapidly quantified both HER2 density and features of nano-organization. In cultured cells, the method was sensitive to subtle variations in HER2 expression. To assess patient samples, we combined qSMLM with tissue touch preparation (touch prep-qSMLM) and examined large areas of intact membranes. For cell lines and patient samples, HER2 copy numbers from FISH showed a significant positive correlation with detected densities from qSMLM and trended with HER2 cluster occupancy.
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Affiliation(s)
- Steven J Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA
| | - Devin L Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA
| | - Veronica Jones
- Department of Surgery, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA
| | - Xueli Liu
- Division of Biostatistics, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA
| | - Daniel Schmolze
- Department of Pathology, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA
| | - Tijana Jovanović-Talisman
- Department of Molecular Medicine, Beckman Research Institute, City of Hope Comprehensive Cancer Center, Duarte, CA, 91010, USA.
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43
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moxMaple3: a Photoswitchable Fluorescent Protein for PALM and Protein Highlighting in Oxidizing Cellular Environments. Sci Rep 2018; 8:14738. [PMID: 30283009 PMCID: PMC6170497 DOI: 10.1038/s41598-018-32955-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 09/19/2018] [Indexed: 11/09/2022] Open
Abstract
The ability of fluorescent proteins (FPs) to fold robustly is fundamental to the autocatalytic formation of the chromophore. While the importance of the tertiary protein structure is well appreciated, the impact of individual amino acid mutations for FPs is often not intuitive and requires direct testing. In this study, we describe the engineering of a monomeric photoswitchable FP, moxMaple3, for use in oxidizing cellular environments, especially the eukaryotic secretory pathway. Surprisingly, a point mutation to replace a cysteine substantially improved the yield of correctly folded FP capable of chromophore formation, regardless of cellular environment. The improved folding of moxMaple3 increases the fraction of visibly tagged fusion proteins, as well as FP performance in PALM super-resolution microscopy, and thus makes moxMaple3 a robust monomeric FP choice for PALM and optical highlighting applications.
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44
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Golfetto O, Wakefield DL, Cacao EE, Avery KN, Kenyon V, Jorand R, Tobin SJ, Biswas S, Gutierrez J, Clinton R, Ma Y, Horne DA, Williams JC, Jovanović-Talisman T. A Platform To Enhance Quantitative Single Molecule Localization Microscopy. J Am Chem Soc 2018; 140:12785-12797. [PMID: 30256630 PMCID: PMC6187371 DOI: 10.1021/jacs.8b04939] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Quantitative single molecule localization microscopy (qSMLM) is a powerful approach to study in situ protein organization. However, uncertainty regarding the photophysical properties of fluorescent reporters can bias the interpretation of detected localizations and subsequent quantification. Furthermore, strategies to efficiently detect endogenous proteins are often constrained by label heterogeneity and reporter size. Here, a new surface assay for molecular isolation (SAMI) was developed for qSMLM and used to characterize photophysical properties of fluorescent proteins and dyes. SAMI-qSMLM afforded robust quantification. To efficiently detect endogenous proteins, we used fluorescent ligands that bind to a specific site on engineered antibody fragments. Both the density and nano-organization of membrane-bound epidermal growth factor receptors (EGFR, HER2, and HER3) were determined by a combination of SAMI, antibody engineering, and pair-correlation analysis. In breast cancer cell lines, we detected distinct differences in receptor density and nano-organization upon treatment with therapeutic agents. This new platform can improve molecular quantification and can be developed to study the local protein environment of intact cells.
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Affiliation(s)
- Ottavia Golfetto
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Devin L Wakefield
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Eliedonna E Cacao
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Kendra N Avery
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Victor Kenyon
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Raphael Jorand
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Steven J Tobin
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Sunetra Biswas
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Jennifer Gutierrez
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Ronald Clinton
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Yuelong Ma
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - David A Horne
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - John C Williams
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
| | - Tijana Jovanović-Talisman
- Department of Molecular Medicine , Beckman Research Institute, City of Hope , 1500 East Duarte Road , Duarte , California 91010 , United States
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45
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Delcanale P, Miret-Ontiveros B, Arista-Romero M, Pujals S, Albertazzi L. Nanoscale Mapping Functional Sites on Nanoparticles by Points Accumulation for Imaging in Nanoscale Topography (PAINT). ACS NANO 2018; 12:7629-7637. [PMID: 30048592 DOI: 10.1021/acsnano.7b09063] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The ability of nanoparticles to selectively recognize a molecular target constitutes the key toward nanomedicine applications such as drug delivery and diagnostics. The activity of such devices is mediated by the presence of multiple copies of functional molecules on the nanostructure surface. Therefore, understanding the number and the distribution of nanoparticle functional groups is of utmost importance for the rational design of effective materials. Analytical methods are available, but to obtain quantitative information at the level of single particles and single functional sites, i. e., going beyond the ensemble, remains highly challenging. Here we introduce the use of an optical nanoscopy technique, DNA points accumulation for imaging in nanoscale topography (DNA-PAINT), to address this issue. Combining subdiffraction spatial resolution with molecular selectivity and sensitivity, DNA-PAINT provides both geometrical and functional information at the level of a single nanostructure. We show how DNA-PAINT can be used to image and quantify relevant functional proteins such as antibodies and streptavidin on nanoparticles and microparticles with nanometric accuracy in 3D and multiple colors. The generality and the applicability of our method without the need for fluorescent labeling hold great promise for the robust quantitative nanocharacterization of functional nanomaterials.
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Affiliation(s)
- Pietro Delcanale
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology , Baldiri Reixac 15-21 , 08028 Barcelona , Spain
| | - Bernat Miret-Ontiveros
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology , Baldiri Reixac 15-21 , 08028 Barcelona , Spain
| | - Maria Arista-Romero
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology , Baldiri Reixac 15-21 , 08028 Barcelona , Spain
| | - Silvia Pujals
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology , Baldiri Reixac 15-21 , 08028 Barcelona , Spain
| | - Lorenzo Albertazzi
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology , Baldiri Reixac 15-21 , 08028 Barcelona , Spain
- Department of Biomedical Engineering and Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , 5612AZ Eindhoven , The Netherlands
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46
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Rossboth B, Arnold AM, Ta H, Platzer R, Kellner F, Huppa JB, Brameshuber M, Baumgart F, Schütz GJ. TCRs are randomly distributed on the plasma membrane of resting antigen-experienced T cells. Nat Immunol 2018; 19:821-827. [PMID: 30013143 PMCID: PMC6071872 DOI: 10.1038/s41590-018-0162-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/14/2018] [Indexed: 12/29/2022]
Abstract
The main function of T cells is to identify harmful antigens as quickly and precisely as possible. Super-resolution microscopy data have indicated that global clustering of T cell antigen receptors (TCRs) occurs before T cell activation. Such pre-activation clustering has been interpreted as representing a potential regulatory mechanism that fine tunes the T cell response. We found here that apparent TCR nanoclustering could be attributed to overcounting artifacts inherent to single-molecule-localization microscopy. Using complementary super-resolution approaches and statistical image analysis, we found no indication of global nanoclustering of TCRs on antigen-experienced CD4+ T cells under non-activating conditions. We also used extensive simulations of super-resolution images to provide quantitative limits for the degree of randomness of the TCR distribution. Together our results suggest that the distribution of TCRs on the plasma membrane is optimized for fast recognition of antigen in the first phase of T cell activation.
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Affiliation(s)
| | | | - Haisen Ta
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - René Platzer
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Florian Kellner
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Johannes B Huppa
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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47
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Rogacki MK, Golfetto O, Tobin SJ, Li T, Biswas S, Jorand R, Zhang H, Radoi V, Ming Y, Svenningsson P, Ganjali D, Wakefield DL, Sideris A, Small AR, Terenius L, Jovanović‐Talisman T, Vukojević V. Dynamic lateral organization of opioid receptors (kappa, mu wt and mu N40D ) in the plasma membrane at the nanoscale level. Traffic 2018; 19:690-709. [PMID: 29808515 PMCID: PMC6120469 DOI: 10.1111/tra.12582] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/06/2018] [Accepted: 05/18/2018] [Indexed: 02/06/2023]
Abstract
Opioid receptors are important pharmacological targets for the management of numerous medical conditions (eg, severe pain), but they are also the gateway to the development of deleterious side effects (eg, opiate addiction). Opioid receptor signaling cascades are well characterized. However, quantitative information regarding their lateral dynamics and nanoscale organization in the plasma membrane remains limited. Since these dynamic properties are important determinants of receptor function, it is crucial to define them. Herein, the nanoscale lateral dynamics and spatial organization of kappa opioid receptor (KOP), wild type mu opioid receptor (MOPwt ), and its naturally occurring isoform (MOPN40D ) were quantitatively characterized using fluorescence correlation spectroscopy and photoactivated localization microscopy. Obtained results, supported by ensemble-averaged Monte Carlo simulations, indicate that these opioid receptors dynamically partition into different domains. In particular, significant exclusion from GM1 ganglioside-enriched domains and partial association with cholesterol-enriched domains was observed. Nanodomain size, receptor population density and the fraction of receptors residing outside of nanodomains were receptor-specific. KOP-containing domains were the largest and most densely populated, with the smallest fraction of molecules residing outside of nanodomains. The opposite was true for MOPN40D . Moreover, cholesterol depletion dynamically regulated the partitioning of KOP and MOPwt , whereas this effect was not observed for MOPN40D .
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Affiliation(s)
- Maciej K. Rogacki
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Ottavia Golfetto
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Steven J. Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Tianyi Li
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Sunetra Biswas
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Raphael Jorand
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Huiying Zhang
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Vlad Radoi
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Yu Ming
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Per Svenningsson
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Daniel Ganjali
- Department of Mechanical and Aerospace EngineeringThe Henry Samueli School of Engineering, University of CaliforniaIrvineCalifornia
| | - Devin L. Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Athanasios Sideris
- Department of Mechanical and Aerospace EngineeringThe Henry Samueli School of Engineering, University of CaliforniaIrvineCalifornia
| | - Alexander R. Small
- Department of Physics and AstronomyCalifornia State Polytechnic UniversityPomonaCalifornia
| | - Lars Terenius
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
- Department of Molecular and Cellular NeurosciencesThe Scripps Research InstituteLa JollaCalifornia
| | | | - Vladana Vukojević
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
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48
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qSR: a quantitative super-resolution analysis tool reveals the cell-cycle dependent organization of RNA Polymerase I in live human cells. Sci Rep 2018; 8:7424. [PMID: 29743503 PMCID: PMC5943247 DOI: 10.1038/s41598-018-25454-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/13/2018] [Indexed: 12/31/2022] Open
Abstract
We present qSR, an analytical tool for the quantitative analysis of single molecule based super-resolution data. The software is created as an open-source platform integrating multiple algorithms for rigorous spatial and temporal characterizations of protein clusters in super-resolution data of living cells. First, we illustrate qSR using a sample live cell data of RNA Polymerase II (Pol II) as an example of highly dynamic sub-diffractive clusters. Then we utilize qSR to investigate the organization and dynamics of endogenous RNA Polymerase I (Pol I) in live human cells, throughout the cell cycle. Our analysis reveals a previously uncharacterized transient clustering of Pol I. Both stable and transient populations of Pol I clusters co-exist in individual living cells, and their relative fraction vary during cell cycle, in a manner correlating with global gene expression. Thus, qSR serves to facilitate the study of protein organization and dynamics with very high spatial and temporal resolutions directly in live cell.
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49
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Bernhem K, Blom H, Brismar H. Quantification of endogenous and exogenous protein expressions of Na,K-ATPase with super-resolution PALM/STORM imaging. PLoS One 2018; 13:e0195825. [PMID: 29694368 PMCID: PMC5918999 DOI: 10.1371/journal.pone.0195825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 03/30/2018] [Indexed: 01/19/2023] Open
Abstract
Transient transfection of fluorescent fusion proteins is a key enabling technology in fluorescent microscopy to spatio-temporally map cellular protein distributions. Transient transfection of proteins may however bypass normal regulation of expression, leading to overexpression artefacts like misallocations and excess amounts. In this study we investigate the use of STORM and PALM microscopy to quantitatively monitor endogenous and exogenous protein expression. Through incorporation of an N-terminal hemagglutinin epitope to a mMaple3 fused Na,K-ATPase (α1 isoform), we analyze the spatial and quantitative changes of plasma membrane Na,K-ATPase localization during competitive transient expression. Quantification of plasma membrane protein density revealed a time dependent increase of Na,K-ATPase, but no increase in size of protein clusters. Results show that after 41h transfection, the total plasma membrane density of Na,K-ATPase increased by 63% while the endogenous contribution was reduced by 16%.
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Affiliation(s)
- Kristoffer Bernhem
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
- Science for Life Laboratory, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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50
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James CC, Zeitz MJ, Calhoun PJ, Lamouille S, Smyth JW. Altered translation initiation of Gja1 limits gap junction formation during epithelial-mesenchymal transition. Mol Biol Cell 2018; 29:797-808. [PMID: 29467255 PMCID: PMC5905293 DOI: 10.1091/mbc.e17-06-0406] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT) is activated during development, wound healing, and pathologies including fibrosis and cancer metastasis. Hallmarks of EMT are remodeling of intercellular junctions and adhesion proteins, including gap junctions. The GJA1 mRNA transcript encoding the gap junction protein connexin43 (Cx43) has been demonstrated to undergo internal translation initiation, yielding truncated isoforms that modulate gap junctions. The PI3K/Akt/mTOR pathway is central to translation regulation and is activated during EMT, leading us to hypothesize that altered translation initiation would contribute to gap junction loss. Using TGF-β-induced EMT as a model, we find reductions in Cx43 gap junctions despite increased transcription and stabilization of Cx43 protein. Biochemical experiments reveal suppression of the internally translated Cx43 isoform, GJA1-20k in a Smad3 and ERK-dependent manner. Ectopic expression of GJA1-20k does not halt EMT, but is sufficient to rescue gap junction formation. GJA1-20k localizes to the Golgi apparatus, and using superresolution localization microscopy we find retention of GJA1-43k at the Golgi in mesenchymal cells lacking GJA1-20k. NativePAGE demonstrates that levels of GJA1-20k regulate GJA1-43k hexamer oligomerization, a limiting step in Cx43 trafficking. These findings reveal alterations in translation initiation as an unexplored mechanism by which the cell regulates Cx43 gap junction formation during EMT.
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Affiliation(s)
- Carissa C James
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA 24016.,Graduate Program in Translational Biology, Medicine, and Health, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - Michael J Zeitz
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA 24016
| | - Patrick J Calhoun
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA 24016.,Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - Samy Lamouille
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA 24016
| | - James W Smyth
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA 24016.,Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
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