1
|
McCall AD. Colocalization by cross-correlation, a new method of colocalization suited for super-resolution microscopy. BMC Bioinformatics 2024; 25:55. [PMID: 38308215 PMCID: PMC10837882 DOI: 10.1186/s12859-024-05675-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 01/25/2024] [Indexed: 02/04/2024] Open
Abstract
BACKGROUND A common goal of scientific microscopic imaging is to determine if a spatial correlation exists between two imaged structures. This is generally accomplished by imaging fluorescently labeled structures and measuring their spatial correlation with a class of image analysis algorithms known as colocalization. However, the most commonly used methods of colocalization have strict limitations, such as requiring overlap in the fluorescent markers and reporting requirements for accurate interpretation of the data, that are often not met. Due to the development of novel super-resolution techniques, which reduce the overlap of the fluorescent signals, a new colocalization method is needed that does not have such strict requirements. RESULTS In order to overcome the limitations of other colocalization algorithms, I developed a new ImageJ/Fiji plugin, Colocalization by cross-correlation (CCC). This method uses cross-correlation over space to identify spatial correlations as a function of distance, removing the overlap requirement and providing more comprehensive results. CCC is compatible with 3D and time-lapse images, and was designed to be easy to use. CCC also generates new images that only show the correlating labeled structures from the input images, a novel feature among the cross-correlating algorithms. CONCLUSIONS CCC is a versatile, powerful, and easy to use colocalization and spatial correlation tool that is available through the Fiji update sites. Full and up to date documentation can be found at https://imagej.net/plugins/colocalization-by-cross-correlation . CCC source code is available at https://github.com/andmccall/Colocalization_by_Cross_Correlation .
Collapse
Affiliation(s)
- Andrew D McCall
- Optical Imaging and Analysis Facility, School of Dental Medicine, University at Buffalo, Buffalo, NY, USA.
| |
Collapse
|
2
|
Morales SV, Mahmood A, Pollard J, Mayne J, Figeys D, Wiseman PW. The LDL receptor is regulated by membrane cholesterol as revealed by fluorescence fluctuation analysis. Biophys J 2023; 122:3783-3797. [PMID: 37559362 PMCID: PMC10541495 DOI: 10.1016/j.bpj.2023.08.005] [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: 01/31/2023] [Revised: 06/17/2023] [Accepted: 08/07/2023] [Indexed: 08/11/2023] Open
Abstract
Membrane cholesterol-rich domains have been shown to be important for regulating a range of membrane protein activities. Low-density lipoprotein receptor (LDLR)-mediated internalization of cholesterol-rich LDL particles is tightly regulated by feedback mechanisms involving intracellular sterol sensors. Since LDLR plays a role in maintaining cellular cholesterol homeostasis, we explore the role that membrane domains may have in regulating LDLR activity. We expressed a fluorescent LDLR-mEGFP construct in HEK293T cells and imaged the unligated receptor or bound to an LDL/DiI fluorescent ligand using total internal reflection fluorescence microscopy. We studied the receptor's spatiotemporal dynamics using fluorescence fluctuation analysis methods. Image cross correlation spectroscopy reveals a lower LDL-to-LDLR binding fraction when membrane cholesterol concentrations are augmented using cholesterol esterase, and a higher binding fraction when the cells are treated with methyl-β-cyclodextrin) to lower membrane cholesterol. This suggests that LDLR's ability to metabolize LDL particles is negatively correlated to membrane cholesterol concentrations. We then tested if a change in activity is accompanied by a change in membrane localization. Image mean-square displacement analysis reveals that unligated LDLR-mEGFP and ligated LDLR-mEGFP/LDL-DiI constructs are transiently confined on the cell membrane, and the size of their confinement domains increases with augmented cholesterol concentrations. Receptor diffusion within the domains and their domain-escape probabilities decrease upon treatment with methyl-β-cyclodextrin, consistent with a change in receptor populations to more confined domains, likely clathrin-coated pits. We propose a feedback model to account for regulation of LDLR within the cell membrane: when membrane cholesterol concentrations are high, LDLR is sequestered in cholesterol-rich domains. These LDLR populations are attenuated in their efficacy to bind and internalize LDL. However, when membrane cholesterol levels drop, LDL has a higher binding affinity to its receptor and the LDLR transits to nascent clathrin-coated domains, where it diffuses at a slower rate while awaiting internalization.
Collapse
Affiliation(s)
- Sebastian V Morales
- Department of Chemistry, Faculty of Science, McGill University, Montreal, Canada
| | - Ahmad Mahmood
- Department of Physics, Faculty of Science, McGill University, Montreal, Canada
| | - Jacob Pollard
- Department of Chemistry, Faculty of Science, McGill University, Montreal, Canada
| | - Janice Mayne
- School of Pharmaceutical Sciences, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Daniel Figeys
- School of Pharmaceutical Sciences, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Paul W Wiseman
- Department of Chemistry, Faculty of Science, McGill University, Montreal, Canada; Department of Physics, Faculty of Science, McGill University, Montreal, Canada.
| |
Collapse
|
3
|
Pierzynska-Mach A, Cainero I, Oneto M, Ferrando-May E, Lanzanò L, Diaspro A. Imaging-based study demonstrates how the DEK nanoscale distribution differentially correlates with epigenetic marks in a breast cancer model. Sci Rep 2023; 13:12749. [PMID: 37550322 PMCID: PMC10406876 DOI: 10.1038/s41598-023-38685-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 07/12/2023] [Indexed: 08/09/2023] Open
Abstract
Epigenetic dysregulation of chromatin is one of the hallmarks of cancer development and progression, and it is continuously investigated as a potential general bio-marker of this complex disease. One of the nuclear factors involved in gene regulation is the unique DEK protein-a histone chaperon modulating chromatin topology. DEK expression levels increase significantly from normal to cancer cells, hence raising the possibility of using DEK as a tumor marker. Although DEK is known to be implicated in epigenetic and transcriptional regulation, the details of these interactions and their relevance in cancer development remain largely elusive. In this work, we investigated the spatial correlation between the nuclear distribution of DEK and chromatin patterns-alongside breast cancer progression-leveraging image cross-correlation spectroscopy (ICCS) coupled with Proximity Ligation Assay (PLA) analysis. We performed our study on the model based on three well-established human breast cell lines to consider this tumor's heterogeneity (MCF10A, MCF7, and MDA-MB-231 cells). Our results show that overexpression of DEK correlates with the overall higher level of spatial proximity between DEK and histone marks corresponding to gene promoters regions (H3K9ac, H3K4me3), although it does not correlate with spatial proximity between DEK and gene enhancers (H3K27ac). Additionally, we observed that colocalizing fractions of DEK and histone marks are lower for the non-invasive cell subtype than for the highly invasive cell line (MDA-MB-231). Thus, this study suggests that the role of DEK on transcriptionally active chromatin regions varies depending on the subtype of the breast cancer cell line.
Collapse
Affiliation(s)
| | - Isotta Cainero
- Nanoscopy and NIC @ IIT, Istituto Italiano di Tecnologia, Via Enrico Melen, 83, 16152, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132, Genoa, Italy
| | - Michele Oneto
- Nanoscopy and NIC @ IIT, Istituto Italiano di Tecnologia, Via Enrico Melen, 83, 16152, Genoa, Italy
| | - Elisa Ferrando-May
- Department of Biology, University of Konstanz, Konstanz, Germany
- German Cancer Research Center, Heidelberg, Germany
| | - Luca Lanzanò
- Nanoscopy and NIC @ IIT, Istituto Italiano di Tecnologia, Via Enrico Melen, 83, 16152, Genoa, Italy
- Department of Physics and Astronomy, University of Catania, Catania, Italy
| | - Alberto Diaspro
- Nanoscopy and NIC @ IIT, Istituto Italiano di Tecnologia, Via Enrico Melen, 83, 16152, Genoa, Italy.
- DIFILAB, Department of Physics, University of Genoa, Genoa, Italy.
| |
Collapse
|
4
|
Cerutti E, D'Amico M, Cainero I, Pelicci PG, Faretta M, Dellino GI, Diaspro A, Lanzanò L. Alterations induced by the PML-RARα oncogene revealed by image cross correlation spectroscopy. Biophys J 2022; 121:4358-4367. [PMID: 36196056 PMCID: PMC9703036 DOI: 10.1016/j.bpj.2022.10.003] [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: 05/20/2022] [Revised: 08/30/2022] [Accepted: 10/03/2022] [Indexed: 12/14/2022] Open
Abstract
The molecular mechanisms that underlie oncogene-induced genomic damage are still poorly understood. To understand how oncogenes affect chromatin architecture, it is important to visualize fundamental processes such as DNA replication and transcription in intact nuclei and quantify the alterations of their spatiotemporal organization induced by oncogenes. Here, we apply superresolution microscopy in combination with image cross correlation spectroscopy to the U937-PR9 cell line, an in vitro model of acute promyelocytic leukemia that allows us to activate the expression of the PML-RARα oncogene and analyze its effects on the spatiotemporal organization of functional nuclear processes. More specifically, we perform Tau-stimulated emission depletion imaging, a superresolution technique based on the concept of separation of photons by lifetime tuning. Tau-stimulated emission depletion imaging is combined with a robust image analysis protocol that quickly produces a value of colocalization fraction on several hundreds of single cells and allows observation of cell-to-cell variability. Upon activation of the oncogene, we detect a significant increase in the fraction of transcription sites colocalized with PML/PML-RARα. This increase of colocalization can be ascribed to oncogene-induced disruption of physiological PML bodies and the abnormal occurrence of a relatively large number of PML-RARα microspeckles. We also detect a significant cell-to-cell variability of this increase of colocalization, which can be ascribed, at least in part, to a heterogeneous response of the cells to the activation of the oncogene. These results prove that our method efficiently reveals oncogene-induced alterations in the spatial organization of nuclear processes and suggest that the abnormal localization of PML-RARα could interfere with the transcription machinery, potentially leading to DNA damage and genomic instability.
Collapse
Affiliation(s)
- Elena Cerutti
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy; Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Morgana D'Amico
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy
| | - Isotta Cainero
- Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Mario Faretta
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Gaetano Ivan Dellino
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy.
| | - Alberto Diaspro
- Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Genoa, Italy; DIFILAB, Department of Physics, University of Genoa, Genoa, Italy
| | - Luca Lanzanò
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy; Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Genoa, Italy.
| |
Collapse
|
5
|
Sato Y, Mustafina KR, Luo Y, Martini C, Thomas DY, Wiseman PW, Hanrahan JW. Nonspecific binding of common anti-CFTR antibodies in ciliated cells of human airway epithelium. Sci Rep 2021; 11:23256. [PMID: 34853321 PMCID: PMC8636639 DOI: 10.1038/s41598-021-02420-x] [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: 07/09/2021] [Accepted: 11/11/2021] [Indexed: 11/10/2022] Open
Abstract
There is evidence that the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel is highly expressed at the apical pole of ciliated cells in human bronchial epithelium (HBE), however recent studies have detected little CFTR mRNA in those cells. To understand this discrepancy we immunostained well differentiated primary HBE cells using CFTR antibodies. We confirmed apical immunofluorescence in ciliated cells and quantified the covariance of the fluorescence signals and that of an antibody against the ciliary marker centrin-2 using image cross-correlation spectroscopy (ICCS). Super-resolution stimulated emission depletion (STED) imaging localized the immunofluorescence in distinct clusters at the bases of the cilia. However, similar apical fluorescence was observed when the monoclonal CFTR antibodies 596, 528 and 769 were used to immunostain ciliated cells expressing F508del-CFTR, or cells lacking CFTR due to a Class I mutation. A BLAST search using the CFTR epitope identified a similar amino acid sequence in the ciliary protein rootletin X1. Its expression level correlated with the intensity of immunostaining by CFTR antibodies and it was detected by 596 antibody after transfection into CFBE cells. These results may explain the high apparent expression of CFTR in ciliated cells and reports of anomalous apical immunofluorescence in well differentiated cells that express F508del-CFTR.
Collapse
Affiliation(s)
- Yukiko Sato
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Kamila R Mustafina
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Chemistry, McGill University, Montréal, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Carolina Martini
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Biochemistry, McGill University, Montréal, Canada
| | - Paul W Wiseman
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Chemistry, McGill University, Montréal, Canada.,Department of Physics, McGill University, Montréal, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada. .,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada. .,Research Institute - McGill University Health Centre, Montréal, Canada.
| |
Collapse
|
6
|
Cerutti E, D'Amico M, Cainero I, Dellino GI, Faretta M, Vicidomini G, Pelicci PG, Bianchini P, Diaspro A, Lanzanò L. Evaluation of sted super-resolution image quality by image correlation spectroscopy (QuICS). Sci Rep 2021; 11:20782. [PMID: 34675304 PMCID: PMC8531054 DOI: 10.1038/s41598-021-00301-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/08/2021] [Indexed: 12/05/2022] Open
Abstract
Quantifying the imaging performances in an unbiased way is of outmost importance in super-resolution microscopy. Here, we describe an algorithm based on image correlation spectroscopy (ICS) that can be used to assess the quality of super-resolution images. The algorithm is based on the calculation of an autocorrelation function and provides three different parameters: the width of the autocorrelation function, related to the spatial resolution; the brightness, related to the image contrast; the relative noise variance, related to the signal-to-noise ratio of the image. We use this algorithm to evaluate the quality of stimulated emission depletion (STED) images of DNA replication foci in U937 cells acquired under different imaging conditions. Increasing the STED depletion power improves the resolution but may reduce the image contrast. Increasing the number of line averages improves the signal-to-noise ratio but facilitates the onset of photobleaching and subsequent reduction of the image contrast. Finally, we evaluate the performances of two different separation of photons by lifetime tuning (SPLIT) approaches: the method of tunable STED depletion power and the commercially available Leica Tau-STED. We find that SPLIT provides an efficient way to improve the resolution and contrast in STED microscopy.
Collapse
Affiliation(s)
- Elena Cerutti
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Via S. Sofia 64, 95123, Catania, Italy.,Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy
| | - Morgana D'Amico
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Via S. Sofia 64, 95123, Catania, Italy
| | - Isotta Cainero
- Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy
| | - Gaetano Ivan Dellino
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20139, Milan, Italy.,Department of Oncology and Hemato-Oncology, University of Milan, 20122, Milan, Italy
| | - Mario Faretta
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20139, Milan, Italy
| | - Giuseppe Vicidomini
- Molecular Microscopy and Spectroscopy, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20139, Milan, Italy.,Department of Oncology and Hemato-Oncology, University of Milan, 20122, Milan, Italy
| | - Paolo Bianchini
- Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy
| | - Alberto Diaspro
- Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy.,DIFILAB, Department of Physics, University of Genoa, via Dodecaneso 33, 16143, Genoa, Italy
| | - Luca Lanzanò
- Department of Physics and Astronomy "Ettore Majorana", University of Catania, Via S. Sofia 64, 95123, Catania, Italy. .,Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Via Enrico Melen 83, Building B, 16152, Genoa, Italy.
| |
Collapse
|
7
|
Ridone P, Pandzic E, Vassalli M, Cox CD, Macmillan A, Gottlieb PA, Martinac B. Disruption of membrane cholesterol organization impairs the activity of PIEZO1 channel clusters. J Gen Physiol 2021; 152:151885. [PMID: 32582958 PMCID: PMC7398139 DOI: 10.1085/jgp.201912515] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 05/12/2020] [Indexed: 11/20/2022] Open
Abstract
The human mechanosensitive ion channel PIEZO1 is gated by membrane tension and regulates essential biological processes such as vascular development and erythrocyte volume homeostasis. Currently, little is known about PIEZO1 plasma membrane localization and organization. Using a PIEZO1-GFP fusion protein, we investigated whether cholesterol enrichment or depletion by methyl-β-cyclodextrin (MBCD) and disruption of membrane cholesterol organization by dynasore affects PIEZO1-GFP's response to mechanical force. Electrophysiological recordings in the cell-attached configuration revealed that MBCD caused a rightward shift in the PIEZO1-GFP pressure-response curve, increased channel latency in response to mechanical stimuli, and markedly slowed channel inactivation. The same effects were seen in native PIEZO1 in N2A cells. STORM superresolution imaging revealed that, at the nanoscale, PIEZO1-GFP channels in the membrane associate as clusters sensitive to membrane manipulation. Both cluster distribution and diffusion rates were affected by treatment with MBCD (5 mM). Supplementation of polyunsaturated fatty acids appeared to sensitize the PIEZO1-GFP response to applied pressure. Together, our results indicate that PIEZO1 function is directly dependent on the membrane composition and lateral organization of membrane cholesterol domains, which coordinate the activity of clustered PIEZO1 channels.
Collapse
Affiliation(s)
- Pietro Ridone
- The Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Elvis Pandzic
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, Lowy Cancer Research Centre, The University of New South Wales, Sydney, NSW, Australia
| | - Massimo Vassalli
- Institute of Biophysics, National Research Council, Genova, Italy
| | - Charles D Cox
- The Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia
| | - Alexander Macmillan
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, Lowy Cancer Research Centre, The University of New South Wales, Sydney, NSW, Australia
| | - Philip A Gottlieb
- Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY
| | - Boris Martinac
- The Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia
| |
Collapse
|
8
|
Reynolds KA, Rosa-Molinar E, Ward RE, Zhang H, Urbanowicz BR, Settles AM. Accelerating biological insight for understudied genes. Integr Comp Biol 2021; 61:2233-2243. [PMID: 33970251 DOI: 10.1093/icb/icab029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The rapid expansion of genome sequence data is increasing the discovery of protein-coding genes across all domains of life. Annotating these genes with reliable functional information is necessary to understand evolution, to define the full biochemical space accessed by nature, and to identify target genes for biotechnology improvements. The vast majority of proteins are annotated based on sequence conservation with no specific biological, biochemical, genetic, or cellular function identified. Recent technical advances throughout the biological sciences enable experimental research on these understudied protein-coding genes in a broader collection of species. However, scientists have incentives and biases to continue focusing on well documented genes within their preferred model organism. This perspective suggests a research model that seeks to break historic silos of research bias by enabling interdisciplinary teams to accelerate biological functional annotation. We propose an initiative to develop coordinated projects of collaborating evolutionary biologists, cell biologists, geneticists, and biochemists that will focus on subsets of target genes in multiple model organisms. Concurrent analysis in multiple organisms takes advantage of evolutionary divergence and selection, which causes individual species to be better suited as experimental models for specific genes. Most importantly, multisystem approaches would encourage transdisciplinary critical thinking and hypothesis testing that is inherently slow in current biological research.
Collapse
Affiliation(s)
- Kimberly A Reynolds
- The Green Center for Systems Biology and the Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Eduardo Rosa-Molinar
- Department of Pharmacology & Toxicology, The University of Kansas, Lawrence, KS 66047, USA
| | - Robert E Ward
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Hongbin Zhang
- Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Breeanna R Urbanowicz
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - A Mark Settles
- Bioengineering Branch, NASA Ames Research Center, Moffett Field, CA USA
| |
Collapse
|
9
|
Auer JMT, Stoddart JJ, Christodoulou I, Lima A, Skouloudaki K, Hall HN, Vukojević V, Papadopoulos DK. Of numbers and movement - understanding transcription factor pathogenesis by advanced microscopy. Dis Model Mech 2020; 13:dmm046516. [PMID: 33433399 PMCID: PMC7790199 DOI: 10.1242/dmm.046516] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Transcription factors (TFs) are life-sustaining and, therefore, the subject of intensive research. By regulating gene expression, TFs control a plethora of developmental and physiological processes, and their abnormal function commonly leads to various developmental defects and diseases in humans. Normal TF function often depends on gene dosage, which can be altered by copy-number variation or loss-of-function mutations. This explains why TF haploinsufficiency (HI) can lead to disease. Since aberrant TF numbers frequently result in pathogenic abnormalities of gene expression, quantitative analyses of TFs are a priority in the field. In vitro single-molecule methodologies have significantly aided the identification of links between TF gene dosage and transcriptional outcomes. Additionally, advances in quantitative microscopy have contributed mechanistic insights into normal and aberrant TF function. However, to understand TF biology, TF-chromatin interactions must be characterised in vivo, in a tissue-specific manner and in the context of both normal and altered TF numbers. Here, we summarise the advanced microscopy methodologies most frequently used to link TF abundance to function and dissect the molecular mechanisms underlying TF HIs. Increased application of advanced single-molecule and super-resolution microscopy modalities will improve our understanding of how TF HIs drive disease.
Collapse
Affiliation(s)
- Julia M T Auer
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh EH4 1XU, UK
| | - Jack J Stoddart
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh EH4 1XU, UK
| | | | - Ana Lima
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh EH4 1XU, UK
| | | | - Hildegard N Hall
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh EH4 1XU, UK
| | - Vladana Vukojević
- Center for Molecular Medicine (CMM), Department of Clinical Neuroscience, Karolinska Institutet, 17176 Stockholm, Sweden
| | | |
Collapse
|
10
|
Oneto M, Scipioni L, Sarmento MJ, Cainero I, Pelicci S, Furia L, Pelicci PG, Dellino GI, Bianchini P, Faretta M, Gratton E, Diaspro A, Lanzanò L. Nanoscale Distribution of Nuclear Sites by Super-Resolved Image Cross-Correlation Spectroscopy. Biophys J 2019; 117:2054-2065. [PMID: 31732142 PMCID: PMC6895719 DOI: 10.1016/j.bpj.2019.10.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/21/2019] [Accepted: 10/29/2019] [Indexed: 02/07/2023] Open
Abstract
Deciphering the spatiotemporal coordination between nuclear functions is important to understand its role in the maintenance of human genome. In this context, super-resolution microscopy has gained considerable interest because it can be used to probe the spatial organization of functional sites in intact single-cell nuclei in the 20-250 nm range. Among the methods that quantify colocalization from multicolor images, image cross-correlation spectroscopy (ICCS) offers several advantages, namely it does not require a presegmentation of the image into objects and can be used to detect dynamic interactions. However, the combination of ICCS with super-resolution microscopy has not been explored yet. Here, we combine dual-color stimulated emission depletion (STED) nanoscopy with ICCS (STED-ICCS) to quantify the nanoscale distribution of functional nuclear sites. We show that super-resolved ICCS provides not only a value of the colocalized fraction but also the characteristic distances associated to correlated nuclear sites. As a validation, we quantify the nanoscale spatial distribution of three different pairs of functional nuclear sites in MCF10A cells. As expected, transcription foci and a transcriptionally repressive histone marker (H3K9me3) are not correlated. Conversely, nascent DNA replication foci and the proliferating cell nuclear antigen(PCNA) protein have a high level of proximity and are correlated at a nanometer distance scale that is close to the limit of our experimental approach. Finally, transcription foci are found at a distance of 130 nm from replication foci, indicating a spatial segregation at the nanoscale. Overall, our data demonstrate that STED-ICCS can be a powerful tool for the analysis of the nanoscale distribution of functional sites in the nucleus.
Collapse
Affiliation(s)
- Michele Oneto
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Lorenzo Scipioni
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, California
| | - Maria J Sarmento
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Isotta Cainero
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy
| | - Simone Pelicci
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy
| | - Laura Furia
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Pier G Pelicci
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Gaetano I Dellino
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Paolo Bianchini
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Mario Faretta
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, California
| | - Alberto Diaspro
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy.
| | - Luca Lanzanò
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy.
| |
Collapse
|
11
|
Lavancier F, Pécot T, Zengzhen L, Kervrann C. Testing independence between two random sets for the analysis of colocalization in bioimaging. Biometrics 2019; 76:36-46. [PMID: 31271216 DOI: 10.1111/biom.13115] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 06/24/2019] [Indexed: 11/30/2022]
Abstract
Colocalization aims at characterizing spatial associations between two fluorescently tagged biomolecules by quantifying the co-occurrence and correlation between the two channels acquired in fluorescence microscopy. Colocalization is presented either as the degree of overlap between the two channels or the overlays of the red and green images, with areas of yellow indicating colocalization of the molecules. This problem remains an open issue in diffraction-limited microscopy and raises new challenges with the emergence of superresolution imaging, a microscopic technique awarded by the 2014 Nobel prize in chemistry. We propose GcoPS, for Geo-coPositioning System, an original method that exploits the random sets structure of the tagged molecules to provide an explicit testing procedure. Our simulation study shows that GcoPS unequivocally outperforms the best competitive methods in adverse situations (noise, irregularly shaped fluorescent patterns, and different optical resolutions). GcoPS is also much faster, a decisive advantage to face the huge amount of data in superresolution imaging. We demonstrate the performances of GcoPS on two biological real data sets, obtained by conventional diffraction-limited microscopy technique and by superresolution technique, respectively.
Collapse
Affiliation(s)
- Frédéric Lavancier
- Laboratoire de Mathématiques Jean Leray, University of Nantes, Nantes, France
| | - Thierry Pécot
- Centre Rennes-Bretagne Atlantique, SERPICO Project Team, Inria, Rennes, France
| | - Liu Zengzhen
- CNRS UMR 144, Space Time Imaging of Endomembranes Dynamics Team, PSL Research University, Paris, France
| | - Charles Kervrann
- Centre Rennes-Bretagne Atlantique, SERPICO Project Team, Inria, Rennes, France
| |
Collapse
|
12
|
Kopecky C, Pandzic E, Parmar A, Szajer J, Lee V, Dupuy A, Arthur A, Fok S, Whan R, Ryder WJ, Rye KA, Cochran BJ. Translocator protein localises to CD11b + macrophages in atherosclerosis. Atherosclerosis 2019; 284:153-159. [PMID: 30913515 DOI: 10.1016/j.atherosclerosis.2019.03.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/12/2019] [Accepted: 03/14/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND AND AIMS Atherosclerosis is characterized by lipid deposition, monocyte infiltration and foam cell formation in the artery wall. Translocator protein (TSPO) is abundantly expressed in lipid rich tissues. Recently, TSPO has been identified as a potential diagnostic tool in cardiovascular disease. The purpose of this study was to determine if the TSPO ligand, 18F-PBR111, can identify early atherosclerotic lesions and if TSPO expression can be used to identify distinct macrophage populations during lesion progression. METHODS ApoE-/- mice were maintained on a high-fat diet for 3 or 12 weeks. C57BL/6J mice maintained on chow diet served as controls. Mice were administered 18F-PBR111 intravenously and PET/CT imaged. After euthanasia, aortas were isolated, fixed and optically cleared. Cleared aortas were immunostained with DAPI, and fluorescently labelled with antibodies to TSPO, the tissue resident macrophage marker F4/80 and the monocyte-derived macrophage marker CD11b. TSPO expression and the macrophage markers were visualised in fatty streaks and established plaques by light sheet microscopy. RESULTS While tissue resident F4/80 + macrophages were evident in the arteries of animals without atherosclerosis, no CD11b + macrophages were observed in these animals. In contrast, established plaques had high CD11b and low F4/80 expression. A ∼3-fold increase in the uptake of 18F-PBR111 was observed in the aortas of atherosclerotic mice relative to controls. CONCLUSIONS Imaging of TSPO expression is a new approach for studying atherosclerotic lesion progression and inflammatory cell infiltration. The TSPO ligand, 18F-PBR111, is a potential clinical diagnostic tool for the detection and quantification of atherosclerotic lesion progression in humans.
Collapse
Affiliation(s)
- Chantal Kopecky
- School of Medical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Elvis Pandzic
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, UNSW Sydney, Sydney, Australia
| | - Arvind Parmar
- Australian Nuclear Science and Technology Organisation, Sydney, Australia
| | - Jeremy Szajer
- Department of Nuclear Medicine, Concord Repatriation General Hospital, Sydney, Australia
| | - Victoria Lee
- School of Medical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Alexander Dupuy
- School of Medical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Andrew Arthur
- Australian Nuclear Science and Technology Organisation, Sydney, Australia
| | - Sandra Fok
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, UNSW Sydney, Sydney, Australia
| | - Renee Whan
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, UNSW Sydney, Sydney, Australia
| | - William J Ryder
- Department of Nuclear Medicine, Concord Repatriation General Hospital, Sydney, Australia
| | - Kerry-Anne Rye
- School of Medical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Blake J Cochran
- School of Medical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia.
| |
Collapse
|
13
|
Cui Y, Zhang X, Yu M, Zhu Y, Xing J, Lin J. Techniques for detecting protein-protein interactions in living cells: principles, limitations, and recent progress. SCIENCE CHINA-LIFE SCIENCES 2019; 62:619-632. [DOI: 10.1007/s11427-018-9500-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 02/12/2019] [Indexed: 01/07/2023]
|
14
|
Theart RP, Loos B, Powrie YSL, Niesler TR. Improved region of interest selection and colocalization analysis in three-dimensional fluorescence microscopy samples using virtual reality. PLoS One 2018; 13:e0201965. [PMID: 30157239 PMCID: PMC6114514 DOI: 10.1371/journal.pone.0201965] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/25/2018] [Indexed: 11/21/2022] Open
Abstract
Although modern fluorescence microscopy produces detailed three-dimensional (3D) datasets, colocalization analysis and region of interest (ROI) selection is most commonly performed two-dimensionally (2D) using maximum intensity projections (MIP). However, these 2D projections exclude much of the available data. Furthermore, 2D ROI selections cannot adequately select complex 3D structures which may inadvertently lead to either the exclusion of relevant or the inclusion of irrelevant data points, consequently affecting the accuracy of the colocalization analysis. Using a virtual reality (VR) enabled system, we demonstrate that 3D visualization, sample interrogation and analysis can be achieved in a highly controlled and precise manner. We calculate several key colocalization metrics using both 2D and 3D derived super-resolved structured illumination-based data sets. Using a neuronal injury model, we investigate the change in colocalization between Tau and acetylated α-tubulin at control conditions, after 6 hours and again after 24 hours. We demonstrate that performing colocalization analysis in 3D enhances its sensitivity, leading to a greater number of statistically significant differences than could be established when using 2D methods. Moreover, by carefully delimiting the 3D structures under analysis using the 3D VR system, we were able to reveal a time dependent loss in colocalization between the Tau and microtubule network as an early event in neuronal injury. This behavior could not be reliably detected using a 2D based projection. We conclude that, using 3D colocalization analysis, biologically relevant samples can be interrogated and assessed with greater precision, thereby better exploiting the potential of fluorescence-based image analysis in biomedical research.
Collapse
Affiliation(s)
- Rensu P. Theart
- Department of Electrical and Electronic Engineering, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | - Ben Loos
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | - Yigael S. L. Powrie
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | - Thomas R. Niesler
- Department of Electrical and Electronic Engineering, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| |
Collapse
|
15
|
Malacrida L, Hedde PN, Ranjit S, Cardarelli F, Gratton E. Visualization of barriers and obstacles to molecular diffusion in live cells by spatial pair-cross-correlation in two dimensions. BIOMEDICAL OPTICS EXPRESS 2018; 9:303-321. [PMID: 29359105 PMCID: PMC5772584 DOI: 10.1364/boe.9.000303] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/09/2017] [Accepted: 12/11/2017] [Indexed: 05/09/2023]
Abstract
Despite recent advances in optical super-resolution, we lack a method that can visualize the path followed by diffusing molecules in the cytoplasm or in the nucleus of cells. Fluorescence correlation spectroscopy (FCS) provides molecular dynamics at the single molecule level by averaging the behavior of many molecules over time at a single spot, thus achieving very good statistics but at only one point in the cell. Earlier image-based methods including raster-scan and spatiotemporal image correlation need spatial averaging over relatively large areas, thus compromising spatial resolution. Here, we use spatial pair-cross-correlation in two dimensions (2D-pCF) to obtain relatively high resolution images of molecular diffusion dynamics and transport in live cells. The 2D-pCF method measures the time for a particle to go from one location to another by cross-correlating the intensity fluctuations at specific points in an image. Hence, a visual map of the average path followed by molecules is created.
Collapse
Affiliation(s)
- Leonel Malacrida
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, USA
- Área de Investigación Respiratoria, Departamento de Fisiopatología, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Uruguay
- LM and PNH contributed equally to this work
| | - Per Niklas Hedde
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, USA
- LM and PNH contributed equally to this work
| | - Suman Ranjit
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, USA
| | - Francesco Cardarelli
- Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa, Italy
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, USA
| |
Collapse
|
16
|
Gopal AA, Ricoult SG, Harris SN, Juncker D, Kennedy TE, Wiseman PW. Spatially Selective Dissection of Signal Transduction in Neurons Grown on Netrin-1 Printed Nanoarrays via Segmented Fluorescence Fluctuation Analysis. ACS NANO 2017; 11:8131-8143. [PMID: 28679208 DOI: 10.1021/acsnano.7b03004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Axonal growth cones extend during neural development in response to precise distributions of extracellular cues. Deleted in colorectal cancer (DCC), a receptor for the chemotropic guidance cue netrin-1, directs F-actin reorganization, and is essential for mammalian neural development. To elucidate how the extracellular distribution of netrin-1 influences the distribution of DCC and F-actin within axonal growth cones, we patterned nanoarrays of substrate bound netrin-1 using lift-off nanocontact printing. The distribution of DCC and F-actin in embryonic rat cortical neuron growth cones was then imaged using total internal reflection fluorescence (TIRF) microscopy. Fluorescence fluctuation analysis via image cross-correlation spectroscopy (ICCS) was applied to extract the molecular density and aggregation state of DCC and F-actin, identifying the fraction of DCC and F-actin colocalizing with the patterned netrin-1 substrate. ICCS measurement of spatially segmented images based on the substrate nanodot patterns revealed distinct molecular distributions of F-actin and DCC in regions directly overlying the nanodots compared to over the reference surface surrounding the nanodots. Quantifiable variations between the populations of DCC and F-actin on and off the nanodots reveal specific responses to the printed protein substrate. We report that nanodots of substrate-bound netrin-1 locally recruit and aggregate DCC and direct F-actin organization. These effects were blocked by tetanus toxin, consistent with netrin-1 locally recruiting DCC to the plasma membrane via a VAMP2-dependent mechanism. Our findings demonstrate the utility of segmented ICCS image analysis, combined with precisely patterned immobilized ligands, to reveal local receptor distribution and signaling within specialized subcellular compartments.
Collapse
Affiliation(s)
- Angelica A Gopal
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| | - Sebastien G Ricoult
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| | - Stephanie N Harris
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| | - David Juncker
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| | - Timothy E Kennedy
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| | - Paul W Wiseman
- Department of Chemistry, ‡Department of Neurology and Neurosurgery, Montreal Neurological Institute, §Department of Biomedical Engineering, Genome Quebec Innovation Centre, and ∥Department of Physics, McGill University , Montreal, Quebec H3A 0G4 Canada
| |
Collapse
|
17
|
Penjweini R, Deville S, Haji Maghsoudi O, Notelaers K, Ethirajan A, Ameloot M. Investigating the effect of poly-l-lactic acid nanoparticles carrying hypericin on the flow-biased diffusive motion of HeLa cell organelles. ACTA ACUST UNITED AC 2017; 71:104-116. [PMID: 28722126 DOI: 10.1111/jphp.12779] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Indexed: 01/04/2023]
Abstract
OBJECTIVES In this study, we investigate in human cervical epithelial HeLa cells the intracellular dynamics and the mutual interaction with the organelles of the poly-l-lactic acid nanoparticles (PLLA NPs) carrying the naturally occurring hydrophobic photosensitizer hypericin. METHODS Temporal and spatiotemporal image correlation spectroscopy was used for the assessment of the intracellular diffusion and directed motion of the nanocarriers by tracking the hypericin fluorescence. Using image cross-correlation spectroscopy and specific fluorescent labelling of endosomes, lysosomes and mitochondria, the NPs dynamics in association with the cell organelles was studied. Static colocalization experiments were interpreted according to the Manders' overlap coefficient. KEY FINDINGS Nanoparticles associate with a small fraction of the whole-organelle population. The organelles moving with NPs exhibit higher directed motion compared to those moving without them. The rate of the directed motion drops substantially after the application of nocodazole. The random component of the organelle motions is not influenced by the NPs. CONCLUSIONS Image correlation and cross-correlation spectroscopy are most appropriate to unravel the motion of the PLLA nanocarrier and to demonstrate that the rate of the directed motion of organelles is influenced by their interaction with the nanocarriers. Not all PLLA-hypericin NPs are associated with organelles.
Collapse
Affiliation(s)
- Rozhin Penjweini
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.,NHLBI Laboratory of Molecular Biophysics, National Institutes of Health, Bethesda, MD, USA
| | - Sarah Deville
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.,Environmental Risk and Health Unit, Flemish Institute for Technological Research, Mol, Belgium
| | - Omid Haji Maghsoudi
- Department of Bioengineering, School of Engineering, Temple University, Philadelphia, PA, USA
| | - Kristof Notelaers
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.,Division of Nanoscopy, Maastricht University, Maastricht, The Netherlands
| | - Anitha Ethirajan
- Institute for Materials Research, IMO-IMOMEC, Hasselt University, Diepenbeek, Belgium
| | - Marcel Ameloot
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| |
Collapse
|
18
|
Gopal AA, Rappaz B, Rouger V, Martyn IB, Dahlberg PD, Meland RJ, Beamish IV, Kennedy TE, Wiseman PW. Netrin-1-Regulated Distribution of UNC5B and DCC in Live Cells Revealed by TICCS. Biophys J 2017; 110:623-634. [PMID: 26840727 DOI: 10.1016/j.bpj.2015.12.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/16/2015] [Accepted: 12/21/2015] [Indexed: 01/01/2023] Open
Abstract
Netrins are secreted proteins that direct cell migration and adhesion during development. Netrin-1 binds its receptors deleted in colorectal cancer (DCC) and the UNC5 homologs (UNC5A-D) to activate downstream signaling that ultimately directs cytoskeletal reorganization. To investigate how netrin-1 regulates the dynamic distribution of DCC and UNC5 homologs, we applied fluorescence confocal and total internal reflection fluorescence microscopy, and sliding window temporal image cross correlation spectroscopy, to measure time profiles of the plasma membrane distribution, aggregation state, and interaction fractions of fluorescently tagged netrin receptors expressed in HEK293T cells. Our measurements reveal changes in receptor aggregation that are consistent with netrin-1-induced recruitment of DCC-enhanced green fluorescent protein (EGFP) from intracellular vesicles to the plasma membrane. Netrin-1 also induced colocalization of coexpressed full-length DCC-EGFP with DCC-T-mCherry, a putative DCC dominant negative that replaces the DCC intracellular domain with mCherry, consistent with netrin-1-induced receptor oligomerization, but with no change in aggregation state with time, providing evidence that signaling via the DCC intracellular domain triggers DCC recruitment to the plasma membrane. UNC5B expressed alone was also recruited by netrin-1 to the plasma membrane. Coexpressed DCC and UNC5 homologs are proposed to form a heteromeric netrin-receptor complex to mediate a chemorepellent response. Application of temporal image cross correlation spectroscopy to image series of cells coexpressing UNC5B-mCherry and DCC-EGFP revealed a netrin-1-induced increase in colocalization, with both receptors recruited to the plasma membrane from preexisting clusters, consistent with vesicular recruitment and receptor heterooligomerization. Plasma membrane recruitment of DCC or UNC5B was blocked by application of the netrin-1 VI-V peptide, which fails to activate chemoattraction, or by pharmacological block of Src family kinase signaling, consistent with receptor recruitment requiring netrin-1-activated signaling. Our findings reveal a mechanism activated by netrin-1 that recruits DCC and UNC5B to the plasma membrane.
Collapse
Affiliation(s)
- Angelica A Gopal
- Department of Chemistry, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; McGill Program in Neuroengineering, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Benjamin Rappaz
- McGill Program in Neuroengineering, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; Department of Physics, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Vincent Rouger
- Department of Chemistry, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Iain B Martyn
- Department of Physics, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Peter D Dahlberg
- Department of Physics, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Rachel J Meland
- Department of Chemistry, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Ian V Beamish
- McGill Program in Neuroengineering, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Timothy E Kennedy
- McGill Program in Neuroengineering, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Paul W Wiseman
- Department of Chemistry, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; McGill Program in Neuroengineering, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; Department of Physics, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
| |
Collapse
|
19
|
Abstract
Labeling fixed brain tissue with fluorescent synaptic and cellular markers can help assess circuit connectivity. Despite the diffraction-limited resolution of light microscopy there are several approaches to identify synaptic contacts onto a cell-of-interest. Understanding which image quantification methods can be applied to estimate cellular and synaptic connectivity at the light microscope level is beneficial to answer a range of questions, from mapping appositions between cellular structures or synaptic proteins to assessing synaptic contact density onto a cell-of-interest. This chapter provides the reader with details of the image analysis methods that can be applied to quantify in situ connectivity patterns at the level of cellular contacts and synaptic appositions.
Collapse
Affiliation(s)
- Mrinalini Hoon
- Department of Biological Structure, University of Washington, Seattle, 98195, WA, USA.
| | - Raunak Sinha
- Department of Physiology and Biophysics, University of Washington, Seattle, 98195, WA, USA
| | - Haruhisa Okawa
- Department of Biological Structure, University of Washington, Seattle, 98195, WA, USA.
| |
Collapse
|
20
|
Burns MC, Nouri M, Veatch SL. Spot size variation FCS in simulations of the 2D Ising model. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2016; 49:214001. [PMID: 27274570 PMCID: PMC4890970 DOI: 10.1088/0022-3727/49/21/214001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Spot variation fluorescence correlation spectroscopy (svFCS) was developed to study the movement and organization of single molecules in plasma membranes. This experimental technique varies the size of an illumination area while measuring correlations in time using standard fluorescence correlation methods. Frequently, this data is interpreted using the assumption that correlation measurements reflect the dynamics of single molecule motions, and not motions of the average composition. Here, we explore how svFCS measurements report on the dynamics of components diffusing within simulations of a 2D Ising model with a conserved order parameter. Simulated correlation functions report on both the fast dynamics of single component mobility and the slower dynamics of the average composition. Over a range of simulation conditions, a conventional svFCS analysis suggests the presence of anomalous diffusion even though single molecule motions are nearly Brownian in these simulations. This misinterpretation is most significant when the surface density of the fluorescent label is elevated, therefore we suggest future measurements be made over a range of tracer densities. Some simulation conditions reproduce qualitative features of published svFCS experimental data. Overall, this work emphasizes the need to probe membranes using multiple complimentary experimental methodologies in order to draw conclusions regarding the nature of spatial and dynamical heterogeneity in these systems.
Collapse
|
21
|
Xu L, Rönnlund D, Aspenström P, Braun LJ, Gad AKB, Widengren J. Resolution, target density and labeling effects in colocalization studies - suppression of false positives by nanoscopy and modified algorithms. FEBS J 2016; 283:882-98. [PMID: 26756570 DOI: 10.1111/febs.13652] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 11/10/2015] [Accepted: 01/08/2016] [Indexed: 11/28/2022]
Abstract
Colocalization analyses of fluorescence images are extensively used to quantify molecular interactions in cells. In recent years, fluorescence nanoscopy has approached resolutions close to molecular dimensions. However, the extent to which image resolution influences different colocalization estimates has not been systematically investigated. In this work, we applied simulations and resolution-tunable stimulated emission depletion microscopy to evaluate how the resolution, molecular density and label size of targeted molecules influence estimates of the most commonly used colocalization algorithms (Pearson correlation coefficient, Manders' M1 and M2 coefficients), as well as estimates by the image cross-correlation spectroscopy method. We investigated the practically measureable extents of colocalization for stimulated emission depletion microscopy with positive and negative control samples with an aim to identifying the strengths and weaknesses of nanoscopic techniques for colocalization studies. At a typical optical resolution of a confocal microscope (200-300 nm), our results indicate that the extent of colocalization is typically overestimated by the tested algorithms, especially at high molecular densities. Only minor effects of this kind were observed at higher resolutions (< 60 nm). By contrast, underestimation of colocalization may occur if the resolution is close to the size of the label/affinity molecules themselves. To suppress false positives at confocal resolutions and high molecular densities, we introduce a statistical variant of Costes' threshold searching algorithm, used in combination with correlation-based methods like the Pearson coefficient and the image cross-correlation spectroscopy approach, to set intensity thresholds separating background noise from signals.
Collapse
Affiliation(s)
- Lei Xu
- Department of Applied Physics, Royal Institute of Technology, KTH, Stockholm, Sweden
| | - Daniel Rönnlund
- Department of Applied Physics, Royal Institute of Technology, KTH, Stockholm, Sweden
| | - Pontus Aspenström
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Laura J Braun
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Annica K B Gad
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden.,Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Jerker Widengren
- Department of Applied Physics, Royal Institute of Technology, KTH, Stockholm, Sweden
| |
Collapse
|
22
|
Penjweini R, Deville S, D'Olieslaeger L, Berden M, Ameloot M, Ethirajan A. Intracellular localization and dynamics of Hypericin loaded PLLA nanocarriers by image correlation spectroscopy. J Control Release 2015; 218:82-93. [DOI: 10.1016/j.jconrel.2015.09.064] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 09/27/2015] [Accepted: 09/28/2015] [Indexed: 01/17/2023]
|
23
|
Intracellular dynamics and fate of polystyrene nanoparticles in A549 Lung epithelial cells monitored by image (cross-) correlation spectroscopy and single particle tracking. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2411-9. [PMID: 26164626 DOI: 10.1016/j.bbamcr.2015.07.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 06/19/2015] [Accepted: 07/07/2015] [Indexed: 11/20/2022]
Abstract
Novel insights in nanoparticle (NP) uptake routes of cells, their intracellular trafficking and subcellular targeting can be obtained through the investigation of their temporal and spatial behavior. In this work, we present the application of image (cross-) correlation spectroscopy (IC(C)S) and single particle tracking (SPT) to monitor the intracellular dynamics of polystyrene (PS) NPs in the human lung carcinoma A549 cell line. The ensemble kinetic behavior of NPs inside the cell was characterized by temporal and spatiotemporal image correlation spectroscopy (TICS and STICS). Moreover, a more direct interpretation of the diffusion and flow detected in the NP motion was obtained by SPT by monitoring individual NPs. Both techniques demonstrate that the PS NP transport in A549 cells is mainly dependent on microtubule-assisted transport. By applying spatiotemporal image cross-correlation spectroscopy (STICCS), the correlated motions of NPs with the early endosomes, late endosomes and lysosomes are identified. PS NPs were equally distributed among the endolysosomal compartment during the time interval of the experiments. The cotransport of the NPs with the lysosomes is significantly larger compared to the other cell organelles. In the present study we show that the complementarity of ICS-based techniques and SPT enables a consistent elaborate model of the complex behavior of NPs inside biological systems.
Collapse
|
24
|
Wiseman PW. Image correlation spectroscopy: principles and applications. Cold Spring Harb Protoc 2015; 2015:336-48. [PMID: 25834267 DOI: 10.1101/pdb.top086124] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Image correlation spectroscopy (ICS) was developed as the imaging analog of fluorescence correlation spectroscopy. Using standard fluorescence microscopy image series as input, different versions of ICS can be used to extract parameters on the molecular transport properties (diffusion and flow) and oligomerization state for fluorescently labeled species in cells. This review introduces the various forms of spatial and temporal ICS and discusses application of these methods to reveal properties of the biomolecules that can be measured from standard fluorescence image time series sampled from cells and neurons.
Collapse
|
25
|
Penjweini R, Smisdom N, Deville S, Ameloot M. Transport and accumulation of PVP-Hypericin in cancer and normal cells characterized by image correlation spectroscopy techniques. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:855-65. [DOI: 10.1016/j.bbamcr.2014.01.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 12/18/2013] [Accepted: 01/16/2014] [Indexed: 01/31/2023]
|
26
|
Piehler J. Spectroscopic techniques for monitoring protein interactions in living cells. Curr Opin Struct Biol 2014; 24:54-62. [DOI: 10.1016/j.sbi.2013.11.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/15/2013] [Accepted: 11/22/2013] [Indexed: 12/21/2022]
|
27
|
Ciccotosto GD, Kozer N, Chow TTY, Chon JWM, Clayton AHA. Aggregation distributions on cells determined by photobleaching image correlation spectroscopy. Biophys J 2013; 104:1056-64. [PMID: 23473488 DOI: 10.1016/j.bpj.2013.01.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 12/17/2012] [Accepted: 01/02/2013] [Indexed: 11/29/2022] Open
Abstract
The organization of molecules into macromolecular (nanometer scale), supramolecular complexes (submicron-to-micron scale), and within subcellular domains, is an important architectural principle of cellular biology and biochemistry. Determining the precise nature and distribution of complexes within the cellular milieu is a challenging biophysical problem. Time-series analysis of laser scanning confocal microscopy images by image correlation spectroscopy (ICS) or fluctuation moments methods provides information on aggregation, flow, and dynamics of fluorescently tagged macromolecules. All the methods to date require a brightness standard to relate the experimental data to absolute aggregation. In this article, we show that ICS as a function of gradual photobleaching is a sensitive indicator of aggregation distribution on the submicron scale. Specifically, in photobleaching ICS, the extent of nonlinearity of the apparent cluster density as a function of bleaching is related to the size of clusters. The analysis is tested using computer simulations on model aggregate systems and then applied to an experimental determination of Aβ peptide aggregation on nerve cells. The analysis reveals time-dependent increases in Aβ1-42 peptide aggregation. Globally, the datasets could be described by a monomer-dimer-tetramer-hexamer or a monomer-dimer-trimer-pentamer model. The results demonstrate the utility of photobleaching with ICS for determining aggregation states on the supramolecular scale in intact cells without the requirement for a brightness standard.
Collapse
Affiliation(s)
- Giuseppe D Ciccotosto
- Department of Pathology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Australia
| | | | | | | | | |
Collapse
|
28
|
Rappaz B, Wiseman PW. Image correlation spectroscopy for measurements of particle densities and colocalization. CURRENT PROTOCOLS IN CELL BIOLOGY 2013; Chapter 4:4.27.1-4.27.15. [PMID: 23728747 DOI: 10.1002/0471143030.cb0427s59] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cells interact with their environment through receptor proteins expressed at their plasma membrane, and protein-protein interactions govern the transduction of signals across the membrane into the cell. Therefore, the ability to measure receptor densities and protein colocalization within the membrane of intact cells is of paramount importance. This unit describes a technique to extract these parameters from fluorescence microscopy images obtained using a commercial confocal laser scanning microscope (CLSM) and other similar types of microscopes. It is based on the analysis of spatial fluorescence intensity fluctuations in the images, which can then be related to particle density and aggregation state via calculation of a spatial autocorrelation function, or used to measure particle colocalization via calculation of a spatial cross-correlation function from dual-color images of proteins tagged with two different fluorophores and imaged in two detection channels. These parameters offer key insights on the interaction of the cell with its environment.
Collapse
Affiliation(s)
- Benjamin Rappaz
- Department of Physics, McGill University, Montreal, Quebec, Canada
| | - Paul W Wiseman
- Department of Physics, McGill University, Montreal, Quebec, Canada.,Department of Chemistry, McGill University, Montreal, Quebec, Canada
| |
Collapse
|
29
|
Cuello AC, Allard S, Ferretti MT. Evidence for the accumulation of Abeta immunoreactive material in the human brain and in transgenic animal models. Life Sci 2012; 91:1141-7. [PMID: 22705309 DOI: 10.1016/j.lfs.2012.05.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 05/11/2012] [Accepted: 05/24/2012] [Indexed: 12/19/2022]
Abstract
In this review we highlight the evidence for an intracellular origin of Abeta (Aβ) amyloid peptides as well as the observations for a pathological accumulation of these peptides in Alzheimer's disease and Down syndrome, as well as in transgenic animal models. We deliberate on the controversy as to whether the intracellular Aβ immunoreactive material is simply an accumulation of unprocessed full length amyloid precursor protein (APP) or a mix of processed APP fragments including Aβ. Finally, we discuss the possible pathological significance of these intracellular APP fragments and the expected future research directions regarding this thought-provoking problem.
Collapse
Affiliation(s)
- A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, 3655 Sir William Osler Promenade, Room 1210, Montreal, Quebec, Canada.
| | | | | |
Collapse
|
30
|
Boyle S, Kolin DL, Bieler JG, Schneck JP, Wiseman PW, Edidin M. Quantum dot fluorescence characterizes the nanoscale organization of T cell receptors for antigen. Biophys J 2012; 101:L57-9. [PMID: 22261075 DOI: 10.1016/j.bpj.2011.10.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 09/19/2011] [Accepted: 10/13/2011] [Indexed: 11/20/2022] Open
Abstract
Changes in the clustering of surface receptors modulate cell responses to ligands. Hence, global measures of receptor clustering can be useful for characterizing cell states. Using T cell receptor for antigen as an example, we show that k-space image correlation spectroscopy of quantum dots blinking detects T cell receptor clusters on a scale of tens of nanometers and reports changes in clustering after T cell activation. Our results offer a general approach to the global analysis of lateral organization and receptor clustering in single cells, and can thus be applied when the cell type of interest is rare.
Collapse
Affiliation(s)
- Sarah Boyle
- Biology Department, The Johns Hopkins University, Baltimore, Maryland, USA
| | | | | | | | | | | |
Collapse
|
31
|
Critical evaluation of quantitative colocalization analysis in confocal fluorescence microscopy. Interdiscip Sci 2012; 4:27-37. [PMID: 22392274 DOI: 10.1007/s12539-012-0117-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 08/21/2011] [Accepted: 12/26/2011] [Indexed: 12/23/2022]
Abstract
Spatial colocalization of fluorescently labeled proteins can reveal valuable information about proteinprotein interactions. Compared to qualitative visual interpretation of dual color images, quantitative colocalization analysis (QCA) provides more objective evaluations to the degree of colocalization. However, the finite resolution power of microscopes and the spatial patterns of intracellular structures may compromise the reliability of many classical QCA methods. In this paper, we discuss the strength and weakness of some mostly used QCA methods. By studying their applications on computer-simulated images and biological images, we show that classical pixel intensity based QCA methods are often vulnerable to coincidental overlapping among resolution elements (resel) distributions and thus not suitable to images with high molecular density or with low resolution. Also, many QCA methods can mistakenly regard long range correlation as colocalization due to protein localization in intracellular structures. The newly developed protein-protein index (PPI) approach is able to reduce the influence from resel overlapping and spatial intracellular pattern compared to previous methods, significantly improving the reliability of QCA.
Collapse
|
32
|
Wang Y, Ledgerwood C, Grills C, Fitzgerald DC, Hamilton PW. A robust co-localisation measurement utilising z-stack image intensity similarities for biological studies. PLoS One 2012; 7:e30632. [PMID: 22363456 PMCID: PMC3281864 DOI: 10.1371/journal.pone.0030632] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 12/19/2011] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Co-localisation is a widely used measurement in immunohistochemical analysis to determine if fluorescently labelled biological entities, such as cells, proteins or molecules share a same location. However the measurement of co-localisation is challenging due to the complex nature of such fluorescent images, especially when multiple focal planes are captured. The current state-of-art co-localisation measurements of 3-dimensional (3D) image stacks are biased by noise and cross-overs from non-consecutive planes. METHOD In this study, we have developed Co-localisation Intensity Coefficients (CICs) and Co-localisation Binary Coefficients (CBCs), which uses rich z-stack data from neighbouring focal planes to identify similarities between image intensities of two and potentially more fluorescently-labelled biological entities. This was developed using z-stack images from murine organotypic slice cultures from central nervous system tissue, and two sets of pseudo-data. A large amount of non-specific cross-over situations are excluded using this method. This proposed method is also proven to be robust in recognising co-localisations even when images are polluted with a range of noises. RESULTS The proposed CBCs and CICs produce robust co-localisation measurements which are easy to interpret, resilient to noise and capable of removing a large amount of false positivity, such as non-specific cross-overs. Performance of this method of measurement is significantly more accurate than existing measurements, as determined statistically using pseudo datasets of known values. This method provides an important and reliable tool for fluorescent 3D neurobiological studies, and will benefit other biological studies which measure fluorescence co-localisation in 3D.
Collapse
Affiliation(s)
- Yinhai Wang
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, United Kingdom
| | - Craig Ledgerwood
- Centre for Infection and Immunity, Queen's University Belfast, Belfast, United Kingdom
| | - Claire Grills
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, United Kingdom
| | - Denise C. Fitzgerald
- Centre for Infection and Immunity, Queen's University Belfast, Belfast, United Kingdom
| | - Peter W. Hamilton
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, United Kingdom
| |
Collapse
|
33
|
Schumann C, Schübbe S, Cavelius C, Kraegeloh A. A correlative approach at characterizing nanoparticle mobility and interactions after cellular uptake. JOURNAL OF BIOPHOTONICS 2012; 5:117-27. [PMID: 21987351 DOI: 10.1002/jbio.201100064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 09/06/2011] [Accepted: 09/19/2011] [Indexed: 05/22/2023]
Abstract
The interactions of nanoparticles with human cells are of large interest in the context of nanomaterial safety. Here, we use live cell imaging and image-based fluorescence correlation methods to determine colocalization of 88 nm and 32 nm silica nanoparticles with endocytotic vesicles derived from the cytoplasmic membrane and lysosomes, as well as to quantify intracellular mobility of internalized particles, in contrast to particle number quantification by counting techniques. In our study, A549 cells are used as a model for human type II alveolar epithelial cells. We present data supporting endocytotic uptake of the particles and subsequent active transport to the perinuclear region. The presence of particles in lamellar bodies is proposed as a potential exocytosis route.
Collapse
Affiliation(s)
- Christian Schumann
- INM - Leibniz Institute for New Materials, Nano Cell Interactions Group, Saarbrücken, Germany
| | | | | | | |
Collapse
|
34
|
Semrau S, Holtzer L, González-Gaitán M, Schmidt T. Quantification of biological interactions with particle image cross-correlation spectroscopy (PICCS). Biophys J 2011; 100:1810-8. [PMID: 21463595 PMCID: PMC3072609 DOI: 10.1016/j.bpj.2010.12.3746] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/24/2010] [Accepted: 12/23/2010] [Indexed: 12/30/2022] Open
Abstract
A multitude of biological processes that involve multiple interaction partners are observed by two-color microscopy. Here we describe an analysis method for the robust quantification of correlation between signals in different color channels: particle image cross-correlation spectroscopy (PICCS). The method, which exploits the superior positional accuracy obtained in single-object and single-molecule microscopy, can extract the correlation fraction and length scale. We applied PICCS to correlation measurements in living tissues. The morphogen Decapentaplegic (Dpp) was imaged in wing imaginal disks of fruit fly larvae and we quantified what fraction of early endosomes contained Dpp.
Collapse
Affiliation(s)
- Stefan Semrau
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | - Laurent Holtzer
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | | | - Thomas Schmidt
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| |
Collapse
|
35
|
Dubiel EA, Martin Y, Vermette P. Bridging the Gap Between Physicochemistry and Interpretation Prevalent in Cell−Surface Interactions. Chem Rev 2011; 111:2900-36. [DOI: 10.1021/cr9002598] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Evan A. Dubiel
- Laboratoire de bio-ingénierie et de biophysique de l’Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 Boulevard de l’Université, Sherbrooke, Québec, Canada J1K 2R1
- Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036 rue Belvédère Sud, Sherbrooke, Québec, Canada J1H 4C4
| | - Yves Martin
- Laboratoire de bio-ingénierie et de biophysique de l’Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 Boulevard de l’Université, Sherbrooke, Québec, Canada J1K 2R1
- Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036 rue Belvédère Sud, Sherbrooke, Québec, Canada J1H 4C4
| | - Patrick Vermette
- Laboratoire de bio-ingénierie et de biophysique de l’Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 Boulevard de l’Université, Sherbrooke, Québec, Canada J1K 2R1
- Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036 rue Belvédère Sud, Sherbrooke, Québec, Canada J1H 4C4
| |
Collapse
|
36
|
Ramírez O, García A, Rojas R, Couve A, Härtel S. Confined displacement algorithm determines true and random colocalization in fluorescence microscopy. J Microsc 2010; 239:173-83. [PMID: 20701655 DOI: 10.1111/j.1365-2818.2010.03369.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The quantification of colocalizing signals in multichannel fluorescence microscopy images depends on the reliable segmentation of corresponding regions of interest, on the selection of appropriate colocalization coefficients, and on a robust statistical criterion to discriminate true from random colocalization. Here, we introduce a confined displacement algorithm based on image correlation spectroscopy in combination with Manders colocalization coefficients M1(ROI) and M2(ROI) to quantify true and random colocalization of a given florescence pattern. We show that existing algorithms based on block scrambling exaggerate the randomization of fluorescent patterns with resulting inappropriately narrow probability density functions and false significance of true colocalization in terms of p values. We further confine our approach to subcellular compartments and show that true and random colocalization can be analysed for model dendrites and for GABA(B) receptor subunits GABA(B)R1/2 in cultured hippocampal neurons. Together, we demonstrate that the confined displacement algorithm detects true colocalization of specific fluorescence patterns down to subcellular levels.
Collapse
Affiliation(s)
- O Ramírez
- Laboratory for Scientific Image Analysis (SCIAN-Lab) at the Anatomy and Developmental Biology Program, ICBM, Universidad de Chile, Santiago, Chile
| | | | | | | | | |
Collapse
|
37
|
Wu Y, Eghbali M, Ou J, Lu R, Toro L, Stefani E. Quantitative determination of spatial protein-protein correlations in fluorescence confocal microscopy. Biophys J 2010; 98:493-504. [PMID: 20141764 PMCID: PMC2814199 DOI: 10.1016/j.bpj.2009.10.037] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 09/30/2009] [Accepted: 10/20/2009] [Indexed: 11/16/2022] Open
Abstract
To quantify spatial protein-protein proximity (colocalization) in paired microscopic images of two sets of proteins labeled by distinct fluorophores, we showed that the cross-correlation and the autocorrelation functions of image intensity consisted of fast and slowly decaying components. The fast component resulted from clusters of proteins specifically labeled, and the slow component resulted from image heterogeneity and a broadly-distributed background. To better evaluate spatial proximity between the two specifically labeled proteins, we extracted the fast-decaying component by fitting the sharp peak in correlation functions to a Gaussian function, which was then used to obtain protein-protein proximity index and the Pearson's correlation coefficient. We also employed the median-filter method as a universal approach for background reduction to minimize nonspecific fluorescence. We illustrated our method by analyzing computer-simulated images and biological images.
Collapse
Affiliation(s)
- Yong Wu
- Department of Anesthesiology, Division of Molecular Medicine, University of California at Los Angeles, California, USA.
| | | | | | | | | | | |
Collapse
|
38
|
Lidke DS, Wilson BS. Caught in the act: quantifying protein behaviour in living cells. Trends Cell Biol 2009; 19:566-74. [PMID: 19801189 DOI: 10.1016/j.tcb.2009.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 08/14/2009] [Accepted: 08/20/2009] [Indexed: 01/23/2023]
Abstract
Protein localization and dynamics both have important roles in cell signal transduction. Biochemical studies have elucidated many details about the chain of events in signal cascades, but the poor temporal resolution and absence of spatial localization in these conventional techniques make it difficult to determine the "where and when" of protein interactions. Over the past decade, imaging technologies and biological tools have developed to a point where many fundamental questions about protein activity can be addressed at the molecular level in living cells, revealing spatio-temporal information that is not provided by traditional biochemical assays. In this review, we illustrate the power of emerging fluorescence microscopy techniques to capture and quantify protein dynamics.
Collapse
Affiliation(s)
- Diane S Lidke
- Department of Pathology and Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | | |
Collapse
|