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Santos R, Bürgi M, Mateos JM, Luciani A, Loffing J. Too bright for 2 dimensions: recent progress in advanced 3-dimensional microscopy of the kidney. Kidney Int 2022; 102:1238-1246. [PMID: 35963448 DOI: 10.1016/j.kint.2022.06.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/19/2022] [Accepted: 06/24/2022] [Indexed: 01/12/2023]
Abstract
The kidney is a structurally and functionally complex organ responsible for the control of water, ion, and other solute homeostasis. Moreover, the kidneys excrete metabolic waste products and produce hormones, such as renin and erythropoietin. The functional unit of the kidney is the nephron, which is composed by a serial arrangement of a filter unit called the renal corpuscle and several tubular segments that modulate the filtered fluid by reabsorption and secretion. Within each kidney, thousands of nephrons are closely intermingled and surrounded by an intricate network of blood vessels and various interstitial cell types, including fibroblasts and immune cells. This complex tissue architecture is essential for proper kidney function. In fact, kidney disease is often reflected or even caused by a derangement of the histologic structures. Frequently, kidney histology is studied using microscopic analysis of 2-dimensional tissue sections, which, however, misses important 3-dimensional spatial information. Reconstruction of serial sections tries to overcome this limitation, but is technically challenging, time-consuming, and often inherently linked to sectioning artifacts. In recent years, advances in tissue preparation (e.g., optical clearing) and new light- and electron-microscopic methods have provided novel avenues for 3-dimensional kidney imaging. Combined with novel machine-learning algorithms, these approaches offer unprecedented options for large-scale and automated analysis of kidney structure and function. This review provides a brief overview of these emerging imaging technologies and presents key examples of how these approaches are already used to study the normal and the diseased kidney.
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Affiliation(s)
- Rui Santos
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Max Bürgi
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - José María Mateos
- Centre for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Alessandro Luciani
- Institute of Physiology, University of Zurich, Zurich, Switzerland; National Centre of Competence in Research "Kidney.CH," University of Zurich, Zurich, Switzerland
| | - Johannes Loffing
- Institute of Anatomy, University of Zurich, Zurich, Switzerland; National Centre of Competence in Research "Kidney.CH," University of Zurich, Zurich, Switzerland.
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2
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Recent Progress in the Correlative Structured Illumination Microscopy. CHEMOSENSORS 2021. [DOI: 10.3390/chemosensors9120364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The super-resolution imaging technique of structured illumination microscopy (SIM) enables the mixing of high-frequency information into the optical transmission domain via light-source modulation, thus breaking the optical diffraction limit. Correlative SIM, which combines other techniques with SIM, offers more versatility or higher imaging resolution than traditional SIM. In this review, we first briefly introduce the imaging mechanism and development trends of conventional SIM. Then, the principles and recent developments of correlative SIM techniques are reviewed. Finally, the future development directions of SIM and its correlative microscopies are presented.
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3
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Wang M, Li M, Jiang S, Gao J, Xi P. Plasmonics meets super-resolution microscopy in biology. Micron 2020; 137:102916. [PMID: 32688264 DOI: 10.1016/j.micron.2020.102916] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/15/2020] [Accepted: 07/09/2020] [Indexed: 12/21/2022]
Abstract
Super-resolution microscopy can reveal the subtle biological processes hidden behind the optical diffraction barrier. Plasmonics is a key nanophotonic that combines electronics and photonics through the interaction of light with the metallic nanostructure. In this review, we survey the recent progresses on plasmonic-assisted super-resolution microscopy. The strong electromagnetic field enhancement trapped near metallic nanostructures offers a unique opportunity to manipulate the illumination scheme for overcoming the diffraction limit. Plasmonic nanoprobes, exploited as surface-enhanced Raman scattering (SERS) and plasmon-enhanced fluorescence nanoparticles, are a major category of contrast agent in super-resolution microscopy. The outstanding challenges, future developments, and potential biological applications are also discussed.
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Affiliation(s)
- Miaoyan Wang
- Department of Biomedical Engineering, College of Engineering, Peking University, 100871 Beijing, China
| | - Meiqi Li
- Department of Biomedical Engineering, College of Engineering, Peking University, 100871 Beijing, China
| | - Shan Jiang
- Department of Biomedical Engineering, College of Engineering, Peking University, 100871 Beijing, China
| | - Juntao Gao
- MOE Key Laboratory of Bioinformatics, Bioinformatics Division, Center for Synthetic & Systems Biology, BNRist, Center for Synthetic & Systems Biology, Tsinghua University, 100084 Beijing, China; Department of Automation, Tsinghua University, 100084 Beijing, China
| | - Peng Xi
- Department of Biomedical Engineering, College of Engineering, Peking University, 100871 Beijing, China.
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4
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Llorente García I, Marsh M. A biophysical perspective on receptor-mediated virus entry with a focus on HIV. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2020; 1862:183158. [PMID: 31863725 PMCID: PMC7156917 DOI: 10.1016/j.bbamem.2019.183158] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 12/14/2022]
Abstract
As part of their entry and infection strategy, viruses interact with specific receptor molecules expressed on the surface of target cells. The efficiency and kinetics of the virus-receptor interactions required for a virus to productively infect a cell is determined by the biophysical properties of the receptors, which are in turn influenced by the receptors' plasma membrane (PM) environments. Currently, little is known about the biophysical properties of these receptor molecules or their engagement during virus binding and entry. Here we review virus-receptor interactions focusing on the human immunodeficiency virus type 1 (HIV), the etiological agent of acquired immunodeficiency syndrome (AIDS), as a model system. HIV is one of the best characterised enveloped viruses, with the identity, roles and structure of the key molecules required for infection well established. We review current knowledge of receptor-mediated HIV entry, addressing the properties of the HIV cell-surface receptors, the techniques used to measure these properties, and the macromolecular interactions and events required for virus entry. We discuss some of the key biophysical principles underlying receptor-mediated virus entry and attempt to interpret the available data in the context of biophysical mechanisms. We also highlight crucial outstanding questions and consider how new tools might be applied to advance understanding of the biophysical properties of viral receptors and the dynamic events leading to virus entry.
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Affiliation(s)
| | - Mark Marsh
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, UK
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5
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Pereira PM, Gustafsson N, Marsh M, Mhlanga MM, Henriques R. Super-beacons: Open-source probes with spontaneous tuneable blinking compatible with live-cell super-resolution microscopy. Traffic 2020; 21:375-385. [PMID: 32170988 PMCID: PMC7643006 DOI: 10.1111/tra.12728] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/10/2020] [Accepted: 03/11/2020] [Indexed: 11/28/2022]
Abstract
Localization-based super-resolution microscopy relies on the detection of individual molecules cycling between fluorescent and non-fluorescent states. These transitions are commonly regulated by high-intensity illumination, imposing constrains to imaging hardware and producing sample photodamage. Here, we propose single-molecule self-quenching as a mechanism to generate spontaneous photoswitching. To demonstrate this principle, we developed a new class of DNA-based open-source super-resolution probes named super-beacons, with photoswitching kinetics that can be tuned structurally, thermally and chemically. The potential of these probes for live-cell compatible super-resolution microscopy without high-illumination or toxic imaging buffers is revealed by imaging interferon inducible transmembrane proteins (IFITMs) at sub-100 nm resolutions.
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Affiliation(s)
- Pedro M. Pereira
- MRC‐Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
- The Francis Crick InstituteLondonUK
- Bacterial Cell BiologyMOSTMICRO, ITQB‐NOVAOeirasPortugal
| | - Nils Gustafsson
- MRC‐Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
- Present address:
Department für Physik and CeNSLudwig‐Maximilians‐UniversitätMunichGermany
| | - Mark Marsh
- MRC‐Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
| | - Musa M. Mhlanga
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health SciencesUniversity of Cape TownCape TownSouth Africa
| | - Ricardo Henriques
- MRC‐Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
- The Francis Crick InstituteLondonUK
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6
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Tosheva KL, Yuan Y, Matos Pereira P, Culley S, Henriques R. Between life and death: strategies to reduce phototoxicity in super-resolution microscopy. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2020; 53:163001. [PMID: 33994582 PMCID: PMC8114953 DOI: 10.1088/1361-6463/ab6b95] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/01/2019] [Accepted: 01/14/2020] [Indexed: 05/23/2023]
Abstract
Super-resolution microscopy (SRM) enables non-invasive, molecule-specific imaging of the internal structure and dynamics of cells with sub-diffraction limit spatial resolution. One of its major limitations is the requirement for high-intensity illumination, generating considerable cellular phototoxicity. This factor considerably limits the capacity for live-cell observations, particularly for extended periods of time. Here, we give an overview of new developments in hardware, software and probe chemistry aiming to reduce phototoxicity. Additionally, we discuss how the choice of biological model and sample environment impacts the capacity for live-cell observations.
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Affiliation(s)
- Kalina L Tosheva
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Yue Yuan
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | | | - Siân Culley
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
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7
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Heller JP, Odii T, Zheng K, Rusakov DA. Imaging tripartite synapses using super-resolution microscopy. Methods 2020; 174:81-90. [PMID: 31153907 PMCID: PMC7144327 DOI: 10.1016/j.ymeth.2019.05.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/03/2019] [Accepted: 05/28/2019] [Indexed: 01/02/2023] Open
Abstract
Astroglia are vital facilitators of brain development, homeostasis, and metabolic support. In addition, they are also essential to the formation and regulation of synaptic circuits. Due to the extraordinary complex, nanoscopic morphology of astrocytes, the underlying cellular mechanisms have been poorly understood. In particular, fine astrocytic processes that can be found in the vicinity of synapses have been difficult to study using traditional imaging techniques. Here, we describe a 3D three-colour super-resolution microscopy approach to unravel the nanostructure of tripartite synapses. The method is based on the SMLM technique direct stochastic optical reconstruction microscopy (dSTORM) which uses conventional fluorophore-labelled antibodies. This approach enables reconstructing the nanoscale localisation of individual astrocytic glutamate transporter (GLT-1) molecules surrounding presynaptic (bassoon) and postsynaptic (Homer1) protein localisations in fixed mouse brain sections. However, the technique is readily adaptable to other types of targets and tissues.
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Affiliation(s)
- Janosch Peter Heller
- UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; FutureNeuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland.
| | - Tuamoru Odii
- UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Department of Physiology, Faculty of Basic Medical Sciences, Alex Ekwueme Federal University Ndufu-Alike Ikwo, PMB 1010 Abakaliki, Nigeria
| | - Kaiyu Zheng
- UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Dmitri A Rusakov
- UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
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8
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Laine RF, Tosheva KL, Gustafsson N, Gray RDM, Almada P, Albrecht D, Risa GT, Hurtig F, Lindås AC, Baum B, Mercer J, Leterrier C, Pereira PM, Culley S, Henriques R. NanoJ: a high-performance open-source super-resolution microscopy toolbox. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2019; 52:163001. [PMID: 33191949 PMCID: PMC7655149 DOI: 10.1088/1361-6463/ab0261] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 01/09/2019] [Accepted: 01/28/2019] [Indexed: 05/18/2023]
Abstract
Super-resolution microscopy (SRM) has become essential for the study of nanoscale biological processes. This type of imaging often requires the use of specialised image analysis tools to process a large volume of recorded data and extract quantitative information. In recent years, our team has built an open-source image analysis framework for SRM designed to combine high performance and ease of use. We named it NanoJ-a reference to the popular ImageJ software it was developed for. In this paper, we highlight the current capabilities of NanoJ for several essential processing steps: spatio-temporal alignment of raw data (NanoJ-Core), super-resolution image reconstruction (NanoJ-SRRF), image quality assessment (NanoJ-SQUIRREL), structural modelling (NanoJ-VirusMapper) and control of the sample environment (NanoJ-Fluidics). We expect to expand NanoJ in the future through the development of new tools designed to improve quantitative data analysis and measure the reliability of fluorescent microscopy studies.
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Affiliation(s)
- Romain F Laine
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Kalina L Tosheva
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Nils Gustafsson
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- Centre for Mathematics and Physics in Life Sciences and Experimental Biology (CoMPLEX), University College London, London, United Kingdom
| | - Robert D M Gray
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- Centre for Mathematics and Physics in Life Sciences and Experimental Biology (CoMPLEX), University College London, London, United Kingdom
| | - Pedro Almada
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - David Albrecht
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Gabriel T Risa
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Fredrik Hurtig
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Ann-Christin Lindås
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Buzz Baum
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Jason Mercer
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Christophe Leterrier
- CNRS, INP, Institute of Neurophysiopathology, NeuroCyto, Aix-Marseille University, Marseille, France
| | - Pedro M Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Siân Culley
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
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9
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Almada P, Pereira PM, Culley S, Caillol G, Boroni-Rueda F, Dix CL, Charras G, Baum B, Laine RF, Leterrier C, Henriques R. Automating multimodal microscopy with NanoJ-Fluidics. Nat Commun 2019. [PMID: 30874553 DOI: 10.1101/320416] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023] Open
Abstract
Combining and multiplexing microscopy approaches is crucial to understand cellular events, but requires elaborate workflows. Here, we present a robust, open-source approach for treating, labelling and imaging live or fixed cells in automated sequences. NanoJ-Fluidics is based on low-cost Lego hardware controlled by ImageJ-based software, making high-content, multimodal imaging easy to implement on any microscope with high reproducibility. We demonstrate its capacity on event-driven, super-resolved live-to-fixed and multiplexed STORM/DNA-PAINT experiments.
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Affiliation(s)
- Pedro Almada
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK
| | - Pedro M Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK
- The Francis Crick Institute, London, NW1 1AT, UK
| | - Siân Culley
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK
- The Francis Crick Institute, London, NW1 1AT, UK
| | - Ghislaine Caillol
- Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, Marseille, 13015, France
| | - Fanny Boroni-Rueda
- Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, Marseille, 13015, France
| | - Christina L Dix
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - Guillaume Charras
- London Centre for Nanotechnology, London, WC1H 0AH, UK
- Institute for the Physics of Living Systems, University College London, London, WC1E 6BT, UK
| | - Buzz Baum
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK
- Institute for the Physics of Living Systems, University College London, London, WC1E 6BT, UK
| | - Romain F Laine
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK.
- The Francis Crick Institute, London, NW1 1AT, UK.
| | - Christophe Leterrier
- Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, Marseille, 13015, France.
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, WC1E 6BT, UK.
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK.
- The Francis Crick Institute, London, NW1 1AT, UK.
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10
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Heller JP, Rusakov DA. A Method to Visualize the Nanoscopic Morphology of Astrocytes In Vitro and In Situ. Methods Mol Biol 2019; 1938:69-84. [PMID: 30617973 DOI: 10.1007/978-1-4939-9068-9_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In recent years it has become apparent that astroglia are not only essential players in brain development, homeostasis, and metabolic support but are also important for the formation and regulation of synaptic circuits. Fine astrocytic processes that can be found in the vicinity of synapses undergo considerable structural plasticity associated with age- and use-dependent changes in neural circuitries. However, due to the extraordinary complex, essentially nanoscopic morphology of astroglia, the underlying cellular mechanisms remain poorly understood.Here we detail a super-resolution microscopy approach, based on the single-molecule localisation microscopy (SMLM) technique direct stochastic optical reconstruction microscopy (dSTORM) to visualize astroglial morphology on the nanoscale. This approach enables visualization of key morphological changes that occur in nanoscopic astrocyte processes, whose characteristic size falls below the diffraction limit of conventional optical microscopy.
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Affiliation(s)
- Janosch P Heller
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, UK.
| | - Dmitri A Rusakov
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, UK.
- Laboratory of Brain Microcircuits, Institute of Neuroscience, University of Nizhny Novgorod, Nizhny Novgorod, Russia.
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11
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Dumas F, Haanappel E. Lipids in infectious diseases - The case of AIDS and tuberculosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:1636-1647. [PMID: 28535936 DOI: 10.1016/j.bbamem.2017.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 05/11/2017] [Accepted: 05/14/2017] [Indexed: 02/07/2023]
Abstract
Lipids play a central role in many infectious diseases. AIDS (Acquired Immune Deficiency Syndrome) and tuberculosis are two of the deadliest infectious diseases to have struck mankind. The pathogens responsible for these diseases, Human Immunodeficiency Virus-1 and Mycobacterium tuberculosis, rely on lipids and on lipid membrane properties to gain access to their host cells, to persist in them and ultimately to egress from their hosts. In this Review, we discuss the life cycles of these pathogens and the roles played by lipids and membranes. We then give an overview of therapies that target lipid metabolism, modulate host membrane properties or implement lipid-based drug delivery systems. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.
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Affiliation(s)
- Fabrice Dumas
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France.
| | - Evert Haanappel
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France
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12
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Almada P, Culley S, Henriques R. PALM and STORM: Into large fields and high-throughput microscopy with sCMOS detectors. Methods 2015; 88:109-21. [PMID: 26079924 DOI: 10.1016/j.ymeth.2015.06.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/28/2015] [Accepted: 06/03/2015] [Indexed: 01/05/2023] Open
Abstract
Single Molecule Localization Microscopy (SMLM) techniques such as Photo-Activation Localization Microscopy (PALM) and Stochastic Optical Reconstruction Microscopy (STORM) enable fluorescence microscopy super-resolution: the overcoming of the resolution barrier imposed by the diffraction of light. These techniques are based on acquiring hundreds or thousands of images of single molecules, locating them and reconstructing a higher-resolution image from the high-precision localizations. These methods generally imply a considerable trade-off between imaging speed and resolution, limiting their applicability to high-throughput workflows. Recent advancements in scientific Complementary Metal-Oxide Semiconductor (sCMOS) camera sensors and localization algorithms reduce the temporal requirements for SMLM, pushing it toward high-throughput microscopy. Here we outline the decisions researchers face when considering how to adapt hardware on a new system for sCMOS sensors with high-throughput in mind.
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Affiliation(s)
- Pedro Almada
- Quantitative Imaging and NanoBiophysics Group, MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Siân Culley
- Quantitative Imaging and NanoBiophysics Group, MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Ricardo Henriques
- Quantitative Imaging and NanoBiophysics Group, MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, United Kingdom.
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13
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Spahn C, Cella-Zannacchi F, Endesfelder U, Heilemann M. Correlative super-resolution imaging of RNA polymerase distribution and dynamics, bacterial membrane and chromosomal structure inEscherichia coli. Methods Appl Fluoresc 2015; 3:014005. [DOI: 10.1088/2050-6120/3/1/014005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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14
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Abstract
Super-resolution light microscopy including pointillist methods based on single molecule localization (e.g., PALM/STORM) allow to image protein structures much smaller than the diffraction limit (200-300 nm). However, commonly used labeling strategies such as antibodies or protein fusions have several important drawbacks, including the risk to alter the function or distribution of the imaged proteins. We recently demonstrated that pointillist imaging can be performed using the alternative labeling technique known as FlAsH, which better preserves protein function, is compatible with live cell imaging, and may help reach single nanometer resolution. We applied FlAsH-PALM to visualize HIV integrase in isolated virions or infected cells, allowing us to obtain sub-diffraction resolution images of this enzyme's spatial distribution and analyze HIV morphology without altering viral replication. The technique should also prove useful to image delicate proteins in intracellular vesicles and organelles at high resolution. Here, we present a detailed protocol in order to facilitate the application of FLAsH-PALM to other proteins and biological structures.
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15
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Li H, Chen D, Xu G, Yu B, Niu H. Three dimensional multi-molecule tracking in thick samples with extended depth-of-field. OPTICS EXPRESS 2015; 23:787-794. [PMID: 25835838 DOI: 10.1364/oe.23.000787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a non-z-scanning multi-molecule tracking system with nano-resolution in all three dimensions and extended depth of field (DOF), which based on distorted grating (DG) and double-helix point spread function (DH-PSF) combination microscopy (DDCM). The critical component in DDCM is a custom designed composite phase mask (PM) combining the functions of DG and DH-PSF. The localization precision and the effective DOF of the home-built DDCM system based on the designed PM were tested. Our experimental results show that the three-dimensional (3D) localization precision for the three diffraction orders of the grating are σ(-1st)(x, y, z) = (6.5 nm, 9.2nm, 23.4 nm), σ(0th)(x, y, z) = (3.7 nm, 2.8nm, 10.3 nm), and σ(+1s)(x, y, z) = (5.8 nm, 6.9 nm, 18.4 nm), respectively. Furthermore, the total effective DOF of the DDCM system is extended to 14 μm. Tracking experiment demonstrated that beads separated over 12 μm along the axial direction at some instants can be localized and tracked successfully.
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Pereira PM, Almada P, Henriques R. High-content 3D multicolor super-resolution localization microscopy. Methods Cell Biol 2015; 125:95-117. [PMID: 25640426 DOI: 10.1016/bs.mcb.2014.10.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Super-resolution (SR) methodologies permit the visualization of cellular structures at near-molecular scale (1-30 nm), enabling novel mechanistic analysis of key events in cell biology not resolvable by conventional fluorescence imaging (∼300-nm resolution). When this level of detail is combined with computing power and fast and reliable analysis software, high-content screenings using SR becomes a practical option to address multiple biological questions. The importance of combining these powerful analytical techniques cannot be ignored, as they can address phenotypic changes on the molecular scale and in a statistically robust manner. In this work, we suggest an easy-to-implement protocol that can be applied to set up a high-content 3D SR experiment with user-friendly and freely available software. The protocol can be divided into two main parts: chamber and sample preparation, where a protocol to set up a direct STORM (dSTORM) sample is presented; and a second part where a protocol for image acquisition and analysis is described. We intend to take the reader step-by-step through the experimental process highlighting possible experimental bottlenecks and possible improvements based on recent developments in the field.
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Affiliation(s)
- Pedro M Pereira
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, London, UK
| | - Pedro Almada
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, London, UK
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, London, UK
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17
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Abstract
During the intracellular phase of the pathogenic lifestyle, Salmonella enterica massively alters the endosomal system of its host cells. Two hallmarks are the remodeling of phagosomes into the Salmonella-containing vacuole (SCV) as a replicative niche, and the formation of tubular structures, such as Salmonella-induced filaments (SIFs). To study the dynamics and the fate of these Salmonella-specific compartments, live cell imaging (LCI) is a method of choice. In this chapter, we compare currently used microscopy techniques and focus on considerations and requirements specific for LCI. Detailed protocols for LCI of Salmonella infection with either confocal laser scanning microscopy (CLSM) or spinning disk confocal microscopy (SDCM) are provided.
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Affiliation(s)
- Alexander Kehl
- Abteilung Mikrobiologie, Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastr. 11, Osnabrück, 49076, Germany
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18
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Abstract
To demonstrate effects of aging visually requires a robust technique that can reproducibly detect small differences in efficiency or kinetics between groups. Investigators of aging will greatly appreciate the benefits of Amnis ImageStream technology ( www.amnis.com/), which combines quantitative flow cytometry with simultaneous high-resolution digital imaging. Imagestream is quantitative, reproducible, feasible with limited samples, and it facilitates in-depth examination of cellular mechanisms between cohorts of samples.
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Affiliation(s)
- Feng Qian
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine, 300 Cedar Street/TAC S413, New Haven, CT, 06520, USA
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Ruth R Montgomery
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine, 300 Cedar Street/TAC S413, New Haven, CT, 06520, USA.
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19
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Whitfield MJ, Luo JP, Thomas WE. Yielding elastic tethers stabilize robust cell adhesion. PLoS Comput Biol 2014; 10:e1003971. [PMID: 25473833 PMCID: PMC4256016 DOI: 10.1371/journal.pcbi.1003971] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 10/06/2014] [Indexed: 12/31/2022] Open
Abstract
Many bacteria and eukaryotic cells express adhesive proteins at the end of tethers that elongate reversibly at constant or near constant force, which we refer to as yielding elasticity. Here we address the function of yielding elastic adhesive tethers with Escherichia coli bacteria as a model for cell adhesion, using a combination of experiments and simulations. The adhesive bond kinetics and tether elasticity was modeled in the simulations with realistic biophysical models that were fit to new and previously published single molecule force spectroscopy data. The simulations were validated by comparison to experiments measuring the adhesive behavior of E. coli in flowing fluid. Analysis of the simulations demonstrated that yielding elasticity is required for the bacteria to remain bound in high and variable flow conditions, because it allows the force to be distributed evenly between multiple bonds. In contrast, strain-hardening and linear elastic tethers concentrate force on the most vulnerable bonds, which leads to failure of the entire adhesive contact. Load distribution is especially important to noncovalent receptor-ligand bonds, because they become exponentially shorter lived at higher force above a critical force, even if they form catch bonds. The advantage of yielding is likely to extend to any blood cells or pathogens adhering in flow, or to any situation where bonds are stretched unequally due to surface roughness, unequal native bond lengths, or conditions that act to unzip the bonds. Cells adhere to surfaces and each other in the presence of forces that would easily overpower the individual noncovalent receptor-ligand bonds that mediate this adhesion, raising the question as to how these bonds cooperate to withstand such high forces. Here we show that cooperation and robust adhesion depends on the elastic properties of the bonds. A type of nonlinear elasticity referred to as elastic yielding ensures that the total force is distributed equally across the individual bonds regardless of geometry. In contrast, with linear or strain-hardening elasticity, the bonds that are stretched the most are exposed to higher forces, which cause them to fail sequentially. This work explains why elastic yielding is found in structurally and evolutionarily diverse adhesive complexes.
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Affiliation(s)
- Matt J. Whitfield
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Jonathon P. Luo
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Wendy E. Thomas
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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20
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Raviv D, Barsi C, Naik N, Feigin M, Raskar R. Pose estimation using time-resolved inversion of diffuse light. OPTICS EXPRESS 2014; 22:20164-20176. [PMID: 25321226 DOI: 10.1364/oe.22.020164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a novel approach for evaluation of position and orientation of geometric shapes from scattered time-resolved data. Traditionally, imaging systems treat scattering as unwanted and are designed to mitigate the effects. Instead, we show here that scattering can be exploited by implementing a system based on a femtosecond laser and a streak camera. The result is accurate estimation of object pose, which is a fundamental tool in analysis of complex scenarios and plays an important role in our understanding of physical phenomena. Here, we experimentally show that for a given geometry, a single incident illumination point yields enough information for pose estimation and tracking after multiple scattering events. Our technique can be used for single-shot imaging behind walls or through turbid media.
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21
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Peckys DB, de Jonge N. Liquid scanning transmission electron microscopy: imaging protein complexes in their native environment in whole eukaryotic cells. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2014; 20:346-65. [PMID: 24548636 DOI: 10.1017/s1431927614000099] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Scanning transmission electron microscopy (STEM) of specimens in liquid, so-called Liquid STEM, is capable of imaging the individual subunits of macromolecular complexes in whole eukaryotic cells in liquid. This paper discusses this new microscopy modality within the context of state-of-the-art microscopy of cells. The principle of operation and equations for the resolution are described. The obtained images are different from those acquired with standard transmission electron microscopy showing the cellular ultrastructure. Instead, contrast is obtained on specific labels. Images can be recorded in two ways, either via STEM at 200 keV electron beam energy using a microfluidic chamber enclosing the cells, or via environmental scanning electron microscopy at 30 keV of cells in a wet environment. The first series of experiments involved the epidermal growth factor receptor labeled with gold nanoparticles. The labels were imaged in whole fixed cells with nanometer resolution. Since the cells can be kept alive in the microfluidic chamber, it is also feasible to detect the labels in unfixed, live cells. The rapid sample preparation and imaging allows studies of multiple whole cells.
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Affiliation(s)
- Diana B Peckys
- 1 Leibniz Institute for New Materials (INM), 66123 Saarbrücken, Germany
| | - Niels de Jonge
- 1 Leibniz Institute for New Materials (INM), 66123 Saarbrücken, Germany
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22
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Tabarin T, Pageon SV, Bach CTT, Lu Y, O'Neill GM, Gooding JJ, Gaus K. Insights into Adhesion Biology Using Single-Molecule Localization Microscopy. Chemphyschem 2014; 15:606-18. [DOI: 10.1002/cphc.201301041] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Indexed: 01/07/2023]
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23
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SANCHEZ-OSORIO ISMAEL, RAMOS FERNANDO, MAYORGA PEDRO, DANTAN EDGAR. FOUNDATIONS FOR MODELING THE DYNAMICS OF GENE REGULATORY NETWORKS: A MULTILEVEL-PERSPECTIVE REVIEW. J Bioinform Comput Biol 2014; 12:1330003. [DOI: 10.1142/s0219720013300037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A promising alternative for unraveling the principles under which the dynamic interactions among genes lead to cellular phenotypes relies on mathematical and computational models at different levels of abstraction, from the molecular level of protein-DNA interactions to the system level of functional relationships among genes. This review article presents, under a bottom–up perspective, a hierarchy of approaches to modeling gene regulatory network dynamics, from microscopic descriptions at the single-molecule level in the spatial context of an individual cell to macroscopic models providing phenomenological descriptions at the population-average level. The reviewed modeling approaches include Molecular Dynamics, Particle-Based Brownian Dynamics, the Master Equation approach, Ordinary Differential Equations, and the Boolean logic abstraction. Each of these frameworks is motivated by a particular biological context and the nature of the insight being pursued. The setting of gene network dynamic models from such frameworks involves assumptions and mathematical artifacts often ignored by the non-specialist. This article aims at providing an entry point for biologists new to the field and computer scientists not acquainted with some recent biophysically-inspired models of gene regulation. The connections promoting intuition between different abstraction levels and the role that approximations play in the modeling process are highlighted throughout the paper.
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Affiliation(s)
- ISMAEL SANCHEZ-OSORIO
- Department of Computer Science, Monterrey Institute of Technology and Higher Education Campus Cuernavaca, Autopista del Sol km 104, Xochitepec, Morelos 62790, Mexico
| | - FERNANDO RAMOS
- Department of Computer Science, Monterrey Institute of Technology and Higher Education Campus Cuernavaca, Autopista del Sol km 104, Xochitepec, Morelos 62790, Mexico
| | - PEDRO MAYORGA
- Department of Computer Science, Monterrey Institute of Technology and Higher Education Campus Cuernavaca, Autopista del Sol km 104, Xochitepec, Morelos 62790, Mexico
| | - EDGAR DANTAN
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Avenida Universidad 1001, Cuernavaca, Morelos 62209, Mexico
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24
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Moeyaert B, Dedecker P. PcSOFI as a smart label-based superresolution microscopy technique. Methods Mol Biol 2014; 1148:261-76. [PMID: 24718807 DOI: 10.1007/978-1-4939-0470-9_17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Stochastic optical fluctuation imaging (SOFI) is a superresolution imaging technique that uses the flickering of fluorescent labels to generate a microscopic image with a resolution better than what the diffraction limit allows. Its adaptation towards fluorescent protein-labeled samples (called photoconversion SOFI or pcSOFI) allows for a straightforward and easily accessible way of generating superresolution images. In this protocol, we will discuss how so-called "smart labels," and specifically the reversibly switchable fluorescent proteins, have opened doors towards superresolution imaging in general and we provide a protocol on how to perform pcSOFI on HeLa cells expressing human β-actin labeled with the reversibly photoswitchable fluorescent protein Dronpa.
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Affiliation(s)
- Benjamien Moeyaert
- Department of Chemistry, University of Leuven, Celestijnenlaan 200 F, 3001, Heverlee, Leuven, Belgium
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25
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Gibson KH, Vorkel D, Meissner J, Verbavatz JM. Fluorescing the electron: strategies in correlative experimental design. Methods Cell Biol 2014; 124:23-54. [PMID: 25287835 DOI: 10.1016/b978-0-12-801075-4.00002-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Correlative light and electron microscopy (CLEM) encompasses a growing number of imaging techniques aiming to combine the benefits of light microscopy, which allows routine labeling of molecules and live-cell imaging of fluorescently tagged proteins with the resolution and ultrastructural detail provided by electron microscopy (EM). Here we review three different strategies that are commonly used in CLEM and we illustrate each approach with one detailed example of their application. The focus is on different options for sample preparation with their respective benefits as well as on the imaging workflows that can be used. The three strategies cover: (1) the combination of live-cell imaging with the high resolution of EM (time-resolved CLEM), (2) the need to identify a fluorescent cell of interest for further exploration by EM (cell sorting), and (3) the subcellular correlation of a fluorescent feature in a cell with its associated ultrastructural features (spatial CLEM). Finally, we discuss future directions for CLEM exploring the possibilities for combining super-resolution microscopy with EM.
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Affiliation(s)
- Kimberley H Gibson
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Daniela Vorkel
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Jana Meissner
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Jean-Marc Verbavatz
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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26
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Müller F, Tora L. Chromatin and DNA sequences in defining promoters for transcription initiation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1839:118-28. [PMID: 24275614 DOI: 10.1016/j.bbagrm.2013.11.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 11/11/2013] [Accepted: 11/11/2013] [Indexed: 01/29/2023]
Abstract
One of the key events in eukaryotic gene regulation and consequent transcription is the assembly of general transcription factors and RNA polymerase II into a functional pre-initiation complex at core promoters. An emerging view of complexity arising from a variety of promoter associated DNA motifs, their binding factors and recent discoveries in characterising promoter associated chromatin properties brings an old question back into the limelight: how is a promoter defined? In addition to position-dependent DNA sequence motifs, accumulating evidence suggests that several parallel acting mechanisms are involved in orchestrating a pattern marked by the state of chromatin and general transcription factor binding in preparation for defining transcription start sites. In this review we attempt to summarise these promoter features and discuss the available evidence pointing at their interactions in defining transcription initiation in developmental contexts. This article is part of a Special Issue entitled: Chromatin and epigenetic regulation of animal development.
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Affiliation(s)
- Ferenc Müller
- School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, B15 2TT Edgbaston, Birmingham, UK.
| | - Làszlò Tora
- Cellular Signaling and Nuclear Dynamics Program, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), UMR 7104 CNRS, UdS, INSERM U964, BP 10142, F-67404 Illkirch Cedex, CU de Strasbourg, France; School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore.
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27
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Super-resolution imaging strategies for cell biologists using a spinning disk microscope. PLoS One 2013; 8:e74604. [PMID: 24130668 PMCID: PMC3793996 DOI: 10.1371/journal.pone.0074604] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 08/05/2013] [Indexed: 11/19/2022] Open
Abstract
In this study we use a spinning disk confocal microscope (SD) to generate super-resolution images of multiple cellular features from any plane in the cell. We obtain super-resolution images by using stochastic intensity fluctuations of biological probes, combining Photoactivation Light-Microscopy (PALM)/Stochastic Optical Reconstruction Microscopy (STORM) methodologies. We compared different image analysis algorithms for processing super-resolution data to identify the most suitable for analysis of particular cell structures. SOFI was chosen for X and Y and was able to achieve a resolution of ca. 80 nm; however higher resolution was possible >30 nm, dependant on the super-resolution image analysis algorithm used. Our method uses low laser power and fluorescent probes which are available either commercially or through the scientific community, and therefore it is gentle enough for biological imaging. Through comparative studies with structured illumination microscopy (SIM) and widefield epifluorescence imaging we identified that our methodology was advantageous for imaging cellular structures which are not immediately at the cell-substrate interface, which include the nuclear architecture and mitochondria. We have shown that it was possible to obtain two coloured images, which highlights the potential this technique has for high-content screening, imaging of multiple epitopes and live cell imaging.
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28
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Beyond sequencing: optical mapping of DNA in the age of nanotechnology and nanoscopy. Curr Opin Biotechnol 2013; 24:690-8. [DOI: 10.1016/j.copbio.2013.01.009] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 01/20/2013] [Accepted: 01/22/2013] [Indexed: 12/25/2022]
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29
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Super-resolution microscopy of the immunological synapse. Curr Opin Immunol 2013; 25:307-12. [PMID: 23746999 DOI: 10.1016/j.coi.2013.04.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/12/2013] [Accepted: 04/15/2013] [Indexed: 12/18/2022]
Abstract
Deciphering the spatial organisation of signalling proteins is the key to understanding the mechanisms underlying immune cell activation. Every advance in imaging technology has led to major breakthroughs in unravelling how receptor and signalling proteins are distributed within the plasma membrane and how membrane signalling is integrated with endosomes and vesicular trafficking. Recently, super-resolution fluorescence microscopy has been applied to immunological synapses, gaining new insights into the nanoscale organisation of signalling processes. Here, we review the advantages and potential of super-resolution microscopy for elucidating the regulation of many aspects of immune signalling.
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