1
|
Rezaeianaran F, Gijs MAM. Difference in Intestine Content of Caenorhabditis elegans When Fed on Non-Pathogenic or Pathogenic Bacteria. MICROMACHINES 2023; 14:1386. [PMID: 37512697 PMCID: PMC10384281 DOI: 10.3390/mi14071386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/30/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023]
Abstract
We investigated the bacterial food digestion and accumulation in wild-type adult Caenorhabditis elegans (C. elegans) worms that have fed on either non-pathogenic RFP-expressing Escherichia coli (E. coli) OP50 or pathogenic-RFP-expressing Pseudomonas aeruginosa (P. aeruginosa) PAO1 during the first 4 days of adulthood. Once the worms had completed their planned feeding cycles, they were loaded on microfluidic chips, where they were fixed to allow high-resolution z-stack fluorescence imaging of their intestines utilizing a Spinning Disk Confocal Microscope (SDCM) equipped with a high-resolution oil-immersion objective (60×). IMARIS software was used to visualize and analyze the obtained images, resulting in the production of three-dimensional constructs of the intestinal bacterial load. We discovered two distinct patterns for the bacteria-derived fluorescence signal in the intestine: (i) individual fluorescent spots, originating from intact bacteria, were present in the fluorescent E. coli-OP50-fed worms, and (ii) individual fluorescent spots (originating from intact bacteria) were dispersed in large regions of diffuse fluorescence (RDF), originating from disrupted bacteria, in fluorescent P. aeruginosa-PAO1-fed worms. We performed a semi-automated single-worm-resolution quantitative analysis of the intestinal bacterial load, which showed that the intestinal bacterial load generally increases with age of the worms, but more rapidly for the fluorescent P. aeruginosa-PAO1-fed worms.
Collapse
Affiliation(s)
- Farzad Rezaeianaran
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Martin A M Gijs
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| |
Collapse
|
2
|
Mennella V, Liu Z. Nanometer-Scale Molecular Mapping by Super-resolution Fluorescence Microscopy. Methods Mol Biol 2022; 2440:305-326. [PMID: 35218547 DOI: 10.1007/978-1-0716-2051-9_18] [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: 06/14/2023]
Abstract
The structural organization of macromolecules and their association in assemblies and organelles is key to understand cellular function. Super-resolution fluorescence microscopy has expanded our toolbox for examining such nanometer-scale cellular structures, by enabling positional mapping of proteins in situ. Here, we detail the workflow to build nanometer-scale maps focusing on two complementary super-resolution modalities: structured illumination microscopy (SIM) and stochastic optical reconstruction microscopy (STORM).
Collapse
Affiliation(s)
- Vito Mennella
- MRC Toxicology Unit, School of Biological Sciences, University of Cambridge, Cambridge, UK.
| | - Zhen Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| |
Collapse
|
3
|
Super-resolution microscopy: a closer look at synaptic dysfunction in Alzheimer disease. Nat Rev Neurosci 2021; 22:723-740. [PMID: 34725519 DOI: 10.1038/s41583-021-00531-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2021] [Indexed: 11/08/2022]
Abstract
The synapse has emerged as a critical neuronal structure in the degenerative process of Alzheimer disease (AD), in which the pathogenic signals of two key players - amyloid-β (Aβ) and tau - converge, thereby causing synaptic dysfunction and cognitive deficits. The synapse presents a dynamic, confined microenvironment in which to explore how key molecules travel, localize, interact and assume different levels of organizational complexity, thereby affecting neuronal function. However, owing to their small size and the diffraction-limited resolution of conventional light microscopic approaches, investigating synaptic structure and dynamics has been challenging. Super-resolution microscopy (SRM) techniques have overcome the resolution barrier and are revolutionizing our quantitative understanding of biological systems in unprecedented spatio-temporal detail. Here we review critical new insights provided by SRM into the molecular architecture and dynamic organization of the synapse and, in particular, the interactions between Aβ and tau in this compartment. We further highlight how SRM can transform our understanding of the molecular pathological mechanisms that underlie AD. The application of SRM for understanding the roles of synapses in AD pathology will provide a stepping stone towards a broader understanding of dysfunction in other subcellular compartments and at cellular and circuit levels in this disease.
Collapse
|
4
|
Baroux C, Schubert V. Technical Review: Microscopy and Image Processing Tools to Analyze Plant Chromatin: Practical Considerations. Methods Mol Biol 2018; 1675:537-589. [PMID: 29052212 DOI: 10.1007/978-1-4939-7318-7_31] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
In situ nucleus and chromatin analyses rely on microscopy imaging that benefits from versatile, efficient fluorescent probes and proteins for static or live imaging. Yet the broad choice in imaging instruments offered to the user poses orientation problems. Which imaging instrument should be used for which purpose? What are the main caveats and what are the considerations to best exploit each instrument's ability to obtain informative and high-quality images? How to infer quantitative information on chromatin or nuclear organization from microscopy images? In this review, we present an overview of common, fluorescence-based microscopy systems and discuss recently developed super-resolution microscopy systems, which are able to bridge the resolution gap between common fluorescence microscopy and electron microscopy. We briefly present their basic principles and discuss their possible applications in the field, while providing experience-based recommendations to guide the user toward best-possible imaging. In addition to raw data acquisition methods, we discuss commercial and noncommercial processing tools required for optimal image presentation and signal evaluation in two and three dimensions.
Collapse
Affiliation(s)
- Célia Baroux
- Department of Plant and Microbial Biology, Zürich-Basel Plant Science Center, University of Zürich, Zollikerstrasse 107, 8008, Zürich, Switzerland.
| | - Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, 06466, Seeland, Germany
| |
Collapse
|
5
|
Magnetic Resonance Microscopy (MRM) of Single Mammalian Myofibers and Myonuclei. Sci Rep 2017; 7:39496. [PMID: 28045071 PMCID: PMC5206738 DOI: 10.1038/srep39496] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 11/21/2016] [Indexed: 11/13/2022] Open
Abstract
Recently, the first magnetic resonance microscopy (MRM) images at the cellular level in isolated mammalian brain tissues were obtained using microsurface coils. These methods can elucidate the cellular origins of MR signals and describe how these signals change over the course of disease progression and therapy. In this work, we explore the capability of these microimaging techniques to visualize mouse muscle fibers and their nuclei. Isolated myofibers expressing lacZ were imaged with and without a stain for β-galactosidase activity (S-Gal + ferric ammonium citrate) that produces both optical and MR contrast. We found that MRM can be used to image single myofibers with 6-μm resolution. The ability to image single myofibers will serve as a valuable tool to study MR properties attributed to healthy and myopathic cells. The ability to image nuclei tagged with MR/Optical gene markers may also find wide use in cell lineage MRI studies.
Collapse
|
6
|
Ye P, Yu H, Houshmandi M. Three/four-dimensional (3D/4D) microscopic imaging and processing in clinical dental research. BMC Oral Health 2016; 16:84. [PMID: 27586147 PMCID: PMC5009657 DOI: 10.1186/s12903-016-0282-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/20/2016] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Confocal laser scanning microscope (CLSM) has been widely employed in our laboratory for structural and functional analysis of clinical dental specimens and live cell imaging of cultured oral epithelial cells. METHODS In this vitro study, a Fluoview 1000 (Olympus) confocal system was utilised to study thick sections of carious lesions (40-100 μm) and periodontal disease tissue samples (20-40 μm) by 2D Z stacking imaging and 3-dimentional (3D) reconstruction. Four-dimensional (4D) imaging when including time or position points was used for live cells to assess penetration/localisation/co-localization of oral pathogen proteins and therapeutic drugs. RESULTS Three-dimensional (3D) reconstruction revealed latent features of carious hard tissues (strongly expressed amelogenin proteins in dentin tubules), and soft tissues (increased glial markers GFAP and S100B in pulp components). We also found the oral microbial specific pathogens, Porphyromonas gingivalis to be widely localised inside the periodontal pocket epithelial tissues as detected by 3D reconstruction from a series of 2D sections from periodontal disease tissue samples. 4D live cell imaging showed the diffusion patterns of fluorescent molecules in response to a bacterial virulence factor, the pathogen (gingipain haemagglutinin) domain that attacked epithelial integrity. This technology also showed uptake of a novel porphyrin-linked metronidazole antibiotic into epithelial cells to kill intracellular oral pathogen, P. gingivalis. CONCLUSIONS Three/four-dimensional (3D/4D) imaging and processing in confocal microscopy is of great interest and benefit to clinical dental researchers.
Collapse
Affiliation(s)
- Ping Ye
- Institute of Dental Research, Oral Health, Westmead Hospital, Westmead, Australia. .,Affiliation of Faculty of Dentistry, the University of Sydney, Sydney, Australia.
| | - Hong Yu
- Microscopy Laboratory, Westmead Institute for Medical Research, Westmead, Australia
| | - Mojgan Houshmandi
- Institute of Dental Research, Oral Health, Westmead Hospital, Westmead, Australia
| |
Collapse
|
7
|
Sayyid F, Kalvala S. On the importance of modelling the internal spatial dynamics of biological cells. Biosystems 2016; 145:53-66. [PMID: 27262415 DOI: 10.1016/j.biosystems.2016.05.012] [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: 07/15/2015] [Revised: 05/25/2016] [Accepted: 05/31/2016] [Indexed: 11/16/2022]
Abstract
Spatial effects such as cell shape have very often been considered negligible in models of cellular pathways, and many existing simulation infrastructures do not take such effects into consideration. Recent experimental results are reversing this judgement by showing that very small spatial variations can make a big difference in the fate of a cell. This is particularly the case when considering eukaryotic cells, which have a complex physical structure and many subtle control mechanisms, but bacteria are also interesting for the huge variation in shape both between species and in different phases of their lifecycle. In this work we perform simulations that measure the effect of three common bacterial shapes on the behaviour of model cellular pathways. To perform these experiments we develop ReDi-Cell, a highly scalable GPGPU cell simulation infrastructure for the modelling of cellular pathways in spatially detailed environments. ReDi-Cell is validated against known-good simulations, prior to its use in new work. We then use ReDi-Cell to conduct novel experiments that demonstrate the effect that three common bacterial shapes (Cocci, Bacilli and Spirilli) have on the behaviour of model cellular pathways. Pathway wavefront shape, pathway concentration gradients, and chemical species distribution are measured in the three different shapes. We also quantify the impact of internal cellular clutter on the same pathways. Through this work we show that variations in the shape or configuration of these common cell shapes alter model cell behaviour.
Collapse
Affiliation(s)
- Faiz Sayyid
- Department of Computer Science, University of Warwick, Coventry, West Midlands, United Kingdom.
| | - Sara Kalvala
- Department of Computer Science, University of Warwick, Coventry, West Midlands, United Kingdom.
| |
Collapse
|
8
|
Mennella V, Hanna R, Kim M. Subdiffraction resolution microscopy methods for analyzing centrosomes organization. Methods Cell Biol 2015; 129:129-152. [PMID: 26175437 DOI: 10.1016/bs.mcb.2015.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In this chapter, we describe the current methods of examining the structure of centrosomes by fluorescence subdiffraction microscopy. By using recently developed microscopy techniques, centrosomal proteins can now be examined in cells with a resolution of only a few nanometers, a level of molecular detail beyond the reach of traditional cell biology methods as confocal and widefield microscopy. We emphasize imaging by three-dimensional structured illumination microscopy, stochastic optical reconstruction microscopy, and quantitative approaches to image data analysis.
Collapse
Affiliation(s)
- Vito Mennella
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada; Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada; Peter Gilgan Centre for Research and Learning, Toronto, ON, Canada
| | - Rachel Hanna
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada; Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Moshe Kim
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada; Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| |
Collapse
|
9
|
Galler K, Bräutigam K, Große C, Popp J, Neugebauer U. Making a big thing of a small cell--recent advances in single cell analysis. Analyst 2015; 139:1237-73. [PMID: 24495980 DOI: 10.1039/c3an01939j] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Single cell analysis is an emerging field requiring a high level interdisciplinary collaboration to provide detailed insights into the complex organisation, function and heterogeneity of life. This review is addressed to life science researchers as well as researchers developing novel technologies. It covers all aspects of the characterisation of single cells (with a special focus on mammalian cells) from morphology to genetics and different omics-techniques to physiological, mechanical and electrical methods. In recent years, tremendous advances have been achieved in all fields of single cell analysis: (1) improved spatial and temporal resolution of imaging techniques to enable the tracking of single molecule dynamics within single cells; (2) increased throughput to reveal unexpected heterogeneity between different individual cells raising the question what characterizes a cell type and what is just natural biological variation; and (3) emerging multimodal approaches trying to bring together information from complementary techniques paving the way for a deeper understanding of the complexity of biological processes. This review also covers the first successful translations of single cell analysis methods to diagnostic applications in the field of tumour research (especially circulating tumour cells), regenerative medicine, drug discovery and immunology.
Collapse
Affiliation(s)
- Kerstin Galler
- Integrated Research and Treatment Center "Center for Sepsis Control and Care", Jena University Hospital, Erlanger Allee 101, 07747 Jena, Germany
| | | | | | | | | |
Collapse
|
10
|
Abstract
Homologous recombination provides high-fidelity DNA repair throughout all domains of life. Live cell fluorescence microscopy offers the opportunity to image individual recombination events in real time providing insight into the in vivo biochemistry of the involved proteins and DNA molecules as well as the cellular organization of the process of homologous recombination. Herein we review the cell biological aspects of mitotic homologous recombination with a focus on Saccharomyces cerevisiae and mammalian cells, but will also draw on findings from other experimental systems. Key topics of this review include the stoichiometry and dynamics of recombination complexes in vivo, the choreography of assembly and disassembly of recombination proteins at sites of DNA damage, the mobilization of damaged DNA during homology search, and the functional compartmentalization of the nucleus with respect to capacity of homologous recombination.
Collapse
Affiliation(s)
- Michael Lisby
- Department of Biology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Rodney Rothstein
- Department of Genetics and Development, Columbia University Medical Center, New York, New York 10032
| |
Collapse
|
11
|
Real-time monitoring of cell migration, phagocytosis and cell surface receptor dynamics using a novel, live-cell opto-microfluidic technique. Anal Chim Acta 2014; 872:95-9. [PMID: 25892074 DOI: 10.1016/j.aca.2014.12.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 12/15/2014] [Accepted: 12/17/2014] [Indexed: 11/22/2022]
Abstract
We report an opto-microfluidic method for continuous and non-interfering monitoring of cell movement and dynamic molecular processes in living cells enabled by the microfluidic "Lab-in-a-Trench" (LiaT) platform. To demonstrate real-time monitoring of heterogeneous cell-cell interactions, cell tracking and agent-induced cell activation dynamics, we observe phagocytosis of Escherichia coli by murine macrophages, migration of active macrophages and LPS-induced CD86 expression in macrophages. The visualization of phagocytosis is facilitated through the loading of green fluorescent protein (GFP) expressing E. coli to the array of cell capture modules before the introduction of macrophages. Simple migration tracking of active macrophages is enabled by a spatio-temporal control of the environment conditions within the LiaT platform. Furthermore, we report an interference-free monitoring of non-modified, endogenous changes in protein expression on the surface of living cells using traditional, antibody immuno-reagents. Throughout the experiment, murine macrophages were captured in the LiaT device and exposed to sub-background levels of fluorescently labeled anti-CD86 antibody. Upon lipopolysaccharide (LPS) stimulation, CD86 changes were visualized in real-time by time-lapse microscopy. This novel opto-microfluidic effect is controlled by the equilibrium of convective-diffusive replenishment of fluorescently labeled antibodies and antibody affinity. Overall, our non-interfering analysis method allows the studying of active cellular processes and endogenous protein dynamics in live cells in a simple and cost-efficient manner.
Collapse
|
12
|
Nienhaus K, Nienhaus GU. Fluorescent proteins for live-cell imaging with super-resolution. Chem Soc Rev 2014; 43:1088-106. [PMID: 24056711 DOI: 10.1039/c3cs60171d] [Citation(s) in RCA: 256] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fluorescent proteins (FPs) from the GFP family have become indispensable as marker tools for imaging live cells, tissues and entire organisms. A wide variety of these proteins have been isolated from natural sources and engineered to optimize their properties as genetically encoded markers. Here we review recent developments in this field. A special focus is placed on photoactivatable FPs, for which the fluorescence emission can be controlled by light irradiation at specific wavelengths. They enable regional optical marking in pulse-chase experiments on live cells and tissues, and they are essential marker tools for live-cell optical imaging with super-resolution. Photoconvertible FPs, which can be activated irreversibly via a photo-induced chemical reaction that either turns on their emission or changes their emission wavelength, are excellent markers for localization-based super-resolution microscopy (e.g., PALM). Patterned illumination microscopy (e.g., RESOLFT), however, requires markers that can be reversibly photoactivated many times. Photoswitchable FPs can be toggled repeatedly between a fluorescent and a non-fluorescent state by means of a light-induced chromophore isomerization coupled to a protonation reaction. We discuss the mechanistic origins of the effect and illustrate how photoswitchable FPs are employed in RESOLFT imaging. For this purpose, special FP variants with low switching fatigue have been introduced in recent years. Despite nearly two decades of FP engineering by many laboratories, there is still room for further improvement of these important markers for live cell imaging.
Collapse
Affiliation(s)
- Karin Nienhaus
- Institute of Applied Physics and Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Straβe 1, 76131 Karlsruhe, Germany
| | | |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Abstract
Microscopic imaging techniques play a pivotal role in the life sciences. Here we describe labeling and imaging methods for live yeast cell imaging. Yeast is an excellent reference organism for biomedical research to investigate fundamental cellular processes, and has gained great popularity also for large-scale imaging-based screens. Methods are described to label live yeast cells with organelle-specific fluorescent dyes or GFP-tagged proteins, and how cells are maintained viable over extended periods of time during microscopy. We point out common pitfalls and potential microscopy artifacts arising from inhomogeneous labeling and depending on cellular physiology. Application and limitation of bleaching techniques to address dynamic processes in the yeast cell are described.
Collapse
Affiliation(s)
- Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | | |
Collapse
|
15
|
Shaikh FY, Crowe JE. Molecular mechanisms driving respiratory syncytial virus assembly. Future Microbiol 2013; 8:123-31. [PMID: 23252497 DOI: 10.2217/fmb.12.132] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Respiratory syncytial virus is a single-stranded RNA virus in the Paramyxoviridae family that preferentially assembles and buds from the apical surface of polarized epithelial cells, forming filamentous structures that contain both viral proteins and the genomic RNA. Recent studies have described both viral and host factors that are involved in ribonucleoprotein assembly and trafficking of viral proteins to the cell surface. At the cell surface, viral proteins assemble into filaments that probably require interactions between viral proteins, host proteins and the cell membrane. Finally, a membrane scission event must occur to release the free virion. This article will review the recent literature describing the mechanisms that drive respiratory syncytial virus assembly and budding.
Collapse
Affiliation(s)
- Fyza Y Shaikh
- Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | | |
Collapse
|
16
|
Gao J, Lyon JA, Szeto DP, Chen J. In vivo imaging and quantitative analysis of zebrafish embryos by digital holographic microscopy. BIOMEDICAL OPTICS EXPRESS 2012; 3:2623-35. [PMID: 23082301 PMCID: PMC3470009 DOI: 10.1364/boe.3.002623] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 09/14/2012] [Accepted: 09/14/2012] [Indexed: 05/15/2023]
Abstract
Digital holographic microscopy (DHM) has been applied extensively to in vitro studies of different living cells. In this paper, we present a novel application of an off-axis DHM system to in vivo study of the development of zebrafish embryos. Even with low magnification microscope objectives, the morphological structures and individual cell types inside developing zebrafish embryos can be clearly observed from reconstructed amplitude images. We further study the dynamic process of blood flow in zebrafish embryos. A calibration routine and post-processing procedures are developed to quantify physiological parameters at different developmental stages. We measure quantitatively the blood flow as well as the heart rate to study the effects of elevated D-glucose (abnormal condition) on circulatory and cardiovascular systems of zebrafish embryos. To enhance our ability to use DHM as a quantitative tool for potential high throughput screening application, the calibration and post-processing algorithms are incorporated into an automated processing software. Our results show that DHM is an excellent non-invasive imaging technique for visualizing the cellular dynamics of organogenesis of zebrafish embryos in vivo.
Collapse
Affiliation(s)
- Jian Gao
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907-1003,
USA
| | - Joseph A. Lyon
- School of Agricultural and Biological Engineering, Purdue University, 225 South University Street, West Lafayette, Indiana 47907-2093,
USA
| | - Daniel P. Szeto
- Department of Natural and Mathematical Sciences, California Baptist University, 8432 Magnolia Avenue, Riverside, California 92504-3297,
USA
| | - Jun Chen
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907-1003,
USA
| |
Collapse
|