1
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Koveal D. Functional principles of genetically encoded fluorescent biosensors for metabolism and their quantitative use. J Neurochem 2024; 168:496-505. [PMID: 37314388 DOI: 10.1111/jnc.15878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 06/15/2023]
Abstract
Genetically encoded fluorescent biosensors provide an attractive means of measuring chemical changes in single cells on fast timescales (milliseconds to seconds). While their most prominent application has been in tracking neural activity and neurotransmitter release, there has been growing interest in developing and deploying new versions of these tools to study brain metabolism. However, the careful use of these tools and the interpretation of the data they provide remain challenging. Many biosensors are subject to interferences that can alter sensor responses within a single cell or between cells, producing ambiguous results. This presents a challenge for quantitation and for our ability to accurately interpret sensor responses. This review describes current methods of sensor quantitation, with a focus on cellular interferences that commonly affect sensor performance, ways to avoid false inferences, and recent advances in sensor optimization to make them more robust.
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Affiliation(s)
- Dorothy Koveal
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia, USA
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2
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Sharma RK, Chafik A, Bertolin G. Aurora kinase A/AURKA functionally interacts with the mitochondrial ATP synthase to regulate energy metabolism and cell death. Cell Death Discov 2023; 9:203. [PMID: 37386025 DOI: 10.1038/s41420-023-01501-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 05/31/2023] [Accepted: 06/19/2023] [Indexed: 07/01/2023] Open
Abstract
Cancer cells often hijack metabolic pathways to obtain the energy required to sustain their proliferation. Understanding the molecular mechanisms underlying cancer cell metabolism is key to fine-tune the metabolic preference of specific tumors, and potentially offer new therapeutic strategies. Here, we show that the pharmacological inhibition of mitochondrial Complex V delays the cell cycle by arresting breast cancer cell models in the G0/G1 phase. Under these conditions, the abundance of the multifunctional protein Aurora kinase A/AURKA is specifically lowered. We then demonstrate that AURKA functionally interacts with the mitochondrial Complex V core subunits ATP5F1A and ATP5F1B. Altering the AURKA/ATP5F1A/ATP5F1B nexus is sufficient to trigger G0/G1 arrest, and this is accompanied by decreased glycolysis and mitochondrial respiration rates. Last, we discover that the roles of the AURKA/ATP5F1A/ATP5F1B nexus depend on the specific metabolic propensity of triple-negative breast cancer cell lines, where they correlate with cell fate. On one hand, the nexus induces G0/G1 arrest in cells relying on oxidative phosphorylation as the main source of energy. On the other hand, it allows to bypass cell cycle arrest and it triggers cell death in cells with a glycolytic metabolism. Altogether, we provide evidence that AURKA and mitochondrial Complex V subunits cooperate to maintain cell metabolism in breast cancer cells. Our work paves the way to novel anti-cancer therapies targeting the AURKA/ATP5F1A/ATP5F1B nexus to lower cancer cell metabolism and proliferation.
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Affiliation(s)
- Rakesh Kumar Sharma
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000, Rennes, France
| | - Abderrahman Chafik
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000, Rennes, France
| | - Giulia Bertolin
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000, Rennes, France.
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3
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Windgasse L, Grashoff C. Multiplexed Molecular Tension Sensor Measurements Using PIE-FLIM. Methods Mol Biol 2023; 2600:221-237. [PMID: 36587101 DOI: 10.1007/978-1-0716-2851-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Genetically encoded Förster Resonance Energy Transfer (FRET)-based tension sensors were developed to enable the quantification of piconewton (pN)-scale forces that act across distinct proteins in living cells and organisms. An important extension of this technology is the multiplexing of tension sensors to monitor several independent FRET probes in parallel. Here we describe how pulsed interleaved excitation (PIE)-fluorescence lifetime imaging microscopy (FLIM) can be implemented to enable the analysis of two co-expressed tension sensor constructs. Our protocol covers all essential steps from biosensor expression and live cell PIE image acquisition to lifetime calculations.
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Affiliation(s)
- Lukas Windgasse
- Department of Quantitative Cell Biology, Institute of Integrative Cell Biology and Physiology, University of Münster, Münster, Germany
| | - Carsten Grashoff
- Department of Quantitative Cell Biology, Institute of Integrative Cell Biology and Physiology, University of Münster, Münster, Germany.
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4
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Vecchia MD, Conte-Daban A, Cappe B, Vandenberg W, Vandenabeele P, Riquet FB, Dedecker P. Spectrally Tunable Förster Resonance Energy Transfer-Based Biosensors Using Organic Dye Grafting. ACS Sens 2022; 7:2920-2927. [PMID: 36162130 DOI: 10.1021/acssensors.2c00066] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Biosensors based on Förster resonance energy transfer (FRET) have revolutionized cellular biology by allowing the direct measurement of biochemical processes in situ. Many genetically encoded sensors make use of fluorescent proteins that are limited in spectral versatility and that allow few ways to change the spectral properties once the construct has been created. In this work, we developed genetically encoded FRET biosensors based on the chemigenetic SNAP and HaloTag domains combined with matching organic fluorophores. We found that the resulting constructs can display comparable responses, kinetics, and reversibility compared to their fluorescent protein-based ancestors, but with the added advantage of spectral versatility, including the availability of red-shifted dye pairs. However, we also find that the introduction of these tags can alter the sensor readout, showing that careful validation is required before applying such constructs in practice. Overall, our approach delivers an innovative methodology that can readily expand the spectral variety and versatility of FRET-based biosensors.
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Affiliation(s)
- Marco Dalla Vecchia
- Lab for NanoBiology, Department of Chemistry, 3001 Leuven, Belgium.,Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.,Cell Death and Inflammation Unit, VIB-UGent Center for Inflammation Research (IRC), Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | | | - Benjamin Cappe
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.,Cell Death and Inflammation Unit, VIB-UGent Center for Inflammation Research (IRC), Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Wim Vandenberg
- Lab for NanoBiology, Department of Chemistry, 3001 Leuven, Belgium
| | - Peter Vandenabeele
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.,Cell Death and Inflammation Unit, VIB-UGent Center for Inflammation Research (IRC), Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Franck B Riquet
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.,Cell Death and Inflammation Unit, VIB-UGent Center for Inflammation Research (IRC), Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium.,Université de Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, 59000 Lille, France
| | - Peter Dedecker
- Lab for NanoBiology, Department of Chemistry, 3001 Leuven, Belgium
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5
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Bourque K, Hawey C, Jiang A, Mazarura GR, Hébert TE. Biosensor-based profiling to track cellular signalling in patient-derived models of dilated cardiomyopathy. Cell Signal 2022; 91:110239. [PMID: 34990783 DOI: 10.1016/j.cellsig.2021.110239] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/06/2021] [Accepted: 12/29/2021] [Indexed: 12/18/2022]
Abstract
Dilated cardiomyopathies (DCM) represent a diverse group of cardiovascular diseases impacting the structure and function of the myocardium. To better treat these diseases, we need to understand the impact of such cardiomyopathies on critical signalling pathways that drive disease progression downstream of receptors we often target therapeutically. Our understanding of cellular signalling events has progressed substantially in the last few years, in large part due to the design, validation and use of biosensor-based approaches to studying such events in cells, tissues and in some cases, living animals. Another transformative development has been the use of human induced pluripotent stem cells (hiPSCs) to generate disease-relevant models from individual patients. We highlight the importance of going beyond monocellular cultures to incorporate the influence of paracrine signalling mediators. Finally, we discuss the recent coalition of these approaches in the context of DCM. We discuss recent work in generating patient-derived models of cardiomyopathies and the utility of using signalling biosensors to track disease progression and test potential therapeutic strategies that can be later used to inform treatment options in patients.
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Affiliation(s)
- Kyla Bourque
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Cara Hawey
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Alyson Jiang
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Grace R Mazarura
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada.
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6
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A cell-based multiplex immunoassay platform using fluorescent protein-barcoded reporter cell lines. Commun Biol 2021; 4:1338. [PMID: 34824350 PMCID: PMC8617053 DOI: 10.1038/s42003-021-02881-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 11/09/2021] [Indexed: 11/08/2022] Open
Abstract
Multiplex immunoassays with acellular antigens are well-established based on solid-phase platforms such as the Luminex® technology. Cell barcoding by amine-reactive fluorescent dyes enables analogous cell-based multiplex assays, but requires multiple labeling reactions and quality checks prior to every assay. Here we describe generation of stable, fluorescent protein-barcoded reporter cell lines suitable for multiplex screening of antibody to membrane proteins. The utility of this cell-based system, with the potential of a 256-plex cell panel, is demonstrated by flow cytometry deconvolution of barcoded cell panels expressing influenza A hemagglutinin trimers, or native human CCR2 or CCR5 multi-span proteins and their epitope-defining mutants. This platform will prove useful for characterizing immunity and discovering antibodies to membrane-associated proteins.
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7
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Imaging intracellular protein interactions/activity in neurons using 2-photon fluorescence lifetime imaging microscopy. Neurosci Res 2021; 179:31-38. [PMID: 34666101 DOI: 10.1016/j.neures.2021.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 12/23/2022]
Abstract
Through the decades, 2-photon fluorescence microscopy has allowed visualization of microstructures, such as synapses, with high spatial resolution in deep brain tissue. However, signal transduction, such as protein activity and protein-protein interaction in neurons in tissues and in vivo, has remained elusive because of the technical difficulty of observing biochemical reactions at the level of subcellular resolution in light-scattering tissues. Recently, 2-photon fluorescence microscopy combined with fluorescence lifetime imaging microscopy (2pFLIM) has enabled visualization of various protein activities and protein-protein interactions at submicrometer resolution in tissue with a reasonable temporal resolution. Thus far, 2pFLIM has been extensively applied for imaging kinase and small GTPase activation in dendritic spines of hippocampal neurons in slice cultures. However, it has been recently applied to various subcellular structures, such as axon terminals and nuclei, and has increased our understanding of spatially organized molecular dynamics. One of the future directions of 2pFLIM utilization is to combine various optogenetic tools for manipulating protein activity. This combination allows the activation of specific proteins with light and visualization of its readout as the activation of downstream molecules. Here, we have introduced the recent application of 2pFLIM for neurons and present the utilization of a new optogenetic tool in combination with 2pFLIM.
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8
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Massengill CI, Day-Cooney J, Mao T, Zhong H. Genetically encoded sensors towards imaging cAMP and PKA activity in vivo. J Neurosci Methods 2021; 362:109298. [PMID: 34339753 PMCID: PMC8659126 DOI: 10.1016/j.jneumeth.2021.109298] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/22/2021] [Accepted: 07/29/2021] [Indexed: 12/26/2022]
Abstract
Cyclic adenosine monophosphate (cAMP) is a universal second messenger that plays a crucial role in diverse biological functions, ranging from transcription to neuronal plasticity, and from development to learning and memory. In the nervous system, cAMP integrates inputs from many neuromodulators across a wide range of timescales - from seconds to hours - to modulate neuronal excitability and plasticity in brain circuits during different animal behavioral states. cAMP signaling events are both cell-specific and subcellularly compartmentalized. The same stimulus may result in different, sometimes opposite, cAMP dynamics in different cells or subcellular compartments. Additionally, the activity of protein kinase A (PKA), a major cAMP effector, is also spatiotemporally regulated. For these reasons, many laboratories have made great strides toward visualizing the intracellular dynamics of cAMP and PKA. To date, more than 80 genetically encoded sensors, including original and improved variants, have been published. It is starting to become possible to visualize cAMP and PKA signaling events in vivo, which is required to study behaviorally relevant cAMP/PKA signaling mechanisms. Despite significant progress, further developments are needed to enhance the signal-to-noise ratio and practical utility of these sensors. This review summarizes the recent advances and challenges in genetically encoded cAMP and PKA sensors with an emphasis on in vivo imaging in the brain during behavior.
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Affiliation(s)
| | - Julian Day-Cooney
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Tianyi Mao
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Haining Zhong
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
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9
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Sipieter F, Cappe B, Leray A, De Schutter E, Bridelance J, Hulpiau P, Van Camp G, Declercq W, Héliot L, Vincent P, Vandenabeele P, Riquet FB. Characteristic ERK1/2 signaling dynamics distinguishes necroptosis from apoptosis. iScience 2021; 24:103074. [PMID: 34568795 PMCID: PMC8449238 DOI: 10.1016/j.isci.2021.103074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 05/21/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022] Open
Abstract
ERK1/2 involvement in cell death remains unclear, although many studies have demonstrated the importance of ERK1/2 dynamics in determining cellular responses. To untangle how ERK1/2 contributes to two cell death programs, we investigated ERK1/2 signaling dynamics during hFasL-induced apoptosis and TNF-induced necroptosis in L929 cells. We observed that ERK1/2 inhibition sensitizes cells to apoptosis while delaying necroptosis. By monitoring ERK1/2 activity by live-cell imaging using an improved ERK1/2 biosensor (EKAR4.0), we reported differential ERK1/2 signaling dynamics between cell survival, apoptosis, and necroptosis. We also decrypted a temporally shifted amplitude- and frequency-modulated (AM/FM) ERK1/2 activity profile in necroptosis versus apoptosis. ERK1/2 inhibition, which disrupted ERK1/2 signaling dynamics, prevented TNF and IL-6 gene expression increase during TNF-induced necroptosis. Using an inducible cell line for activated MLKL, the final executioner of necroptosis, we showed ERK1/2 and its distinctive necroptotic ERK1/2 activity dynamics to be positioned downstream of MLKL.
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Affiliation(s)
- François Sipieter
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium.,Université de Lille, Lille, France
| | - Benjamin Cappe
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Aymeric Leray
- Laboratoire Interdisciplinaire Carnot De Bourgogne, UMR 6303 CNRS-Université de Bourgogne Franche-Comté, 21078 Dijon, France
| | - Elke De Schutter
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium.,Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Prins Boudewijnlaan 43/6, Edegem, 2650 Antwerp, Belgium
| | - Jolien Bridelance
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Paco Hulpiau
- Data Mining and Modeling for Biomedicine (DaMBi), VIB Center for Inflammation Research, Ghent, Belgium
| | - Guy Van Camp
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Prins Boudewijnlaan 43/6, Edegem, 2650 Antwerp, Belgium.,Center for Oncological Research, University of Antwerp and Antwerp University Hospital, Universiteitsplein 1, Wilrijk, 2610 Antwerp, Belgium
| | - Wim Declercq
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Laurent Héliot
- Team Biophotonique Cellulaire Fonctionnelle, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS UMR 8523, 59655 Villeneuve d'Ascq, France
| | - Pierre Vincent
- Sorbonne Université, CNRS, Neurobiology of Adaptative Processes, UMR8256, 75005 Paris, France
| | - Peter Vandenabeele
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium
| | - Franck B Riquet
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.,Molecular Signaling and Cell Death Unit, VIB Center for Inflammation Research, Technologiepark 71, Zwijnaarde, 9052 Ghent, Belgium.,Université de Lille, Lille, France
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10
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Van Genechten W, Van Dijck P, Demuyser L. Fluorescent toys 'n' tools lighting the way in fungal research. FEMS Microbiol Rev 2021; 45:fuab013. [PMID: 33595628 PMCID: PMC8498796 DOI: 10.1093/femsre/fuab013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 02/14/2021] [Indexed: 12/13/2022] Open
Abstract
Although largely overlooked compared to bacterial infections, fungal infections pose a significant threat to the health of humans and other organisms. Many pathogenic fungi, especially Candida species, are extremely versatile and flexible in adapting to various host niches and stressful situations. This leads to high pathogenicity and increasing resistance to existing drugs. Due to the high level of conservation between fungi and mammalian cells, it is hard to find fungus-specific drug targets for novel therapy development. In this respect, it is vital to understand how these fungi function on a molecular, cellular as well as organismal level. Fluorescence imaging allows for detailed analysis of molecular mechanisms, cellular structures and interactions on different levels. In this manuscript, we provide researchers with an elaborate and contemporary overview of fluorescence techniques that can be used to study fungal pathogens. We focus on the available fluorescent labelling techniques and guide our readers through the different relevant applications of fluorescent imaging, from subcellular events to multispecies interactions and diagnostics. As well as cautioning researchers for potential challenges and obstacles, we offer hands-on tips and tricks for efficient experimentation and share our expert-view on future developments and possible improvements.
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Affiliation(s)
- Wouter Van Genechten
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200g, 3001 Leuven-Heverlee, Belgium
| | - Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
| | - Liesbeth Demuyser
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
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11
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Murphy KJ, Reed DA, Trpceski M, Herrmann D, Timpson P. Quantifying and visualising the nuances of cellular dynamics in vivo using intravital imaging. Curr Opin Cell Biol 2021; 72:41-53. [PMID: 34091131 DOI: 10.1016/j.ceb.2021.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/23/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022]
Abstract
Intravital imaging is a powerful technology used to quantify and track dynamic changes in live cells and tissues within an intact environment. The ability to watch cell biology in real-time 'as it happens' has provided novel insight into tissue homeostasis, as well as disease initiation, progression and response to treatment. In this minireview, we highlight recent advances in the field of intravital microscopy, touching upon advances in awake versus anaesthesia-based approaches, as well as the integration of biosensors into intravital imaging. We also discuss current challenges that, in our opinion, need to be overcome to further advance the field of intravital imaging at the single-cell, subcellular and molecular resolution to reveal nuances of cell behaviour that can be targeted in complex disease settings.
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Affiliation(s)
- Kendelle J Murphy
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Daniel A Reed
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Michael Trpceski
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia
| | - David Herrmann
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia.
| | - Paul Timpson
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia.
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12
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Simultaneous readout of multiple FRET pairs using photochromism. Nat Commun 2021; 12:2005. [PMID: 33790271 PMCID: PMC8012603 DOI: 10.1038/s41467-021-22043-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/17/2021] [Indexed: 01/11/2023] Open
Abstract
Förster resonant energy transfer (FRET) is a powerful mechanism to probe associations in situ. Simultaneously performing more than one FRET measurement can be challenging due to the spectral bandwidth required for the donor and acceptor fluorophores. We present an approach to distinguish overlapping FRET pairs based on the photochromism of the donor fluorophores, even if the involved fluorophores display essentially identical absorption and emission spectra. We develop the theory underlying this method and validate our approach using numerical simulations. To apply our system, we develop rsAKARev, a photochromic biosensor for cAMP-dependent protein kinase (PKA), and combine it with the spectrally-identical biosensor EKARev, a reporter for extracellular signal-regulated kinase (ERK) activity, to deliver simultaneous readout of both activities in the same cell. We further perform multiplexed PKA, ERK, and calcium measurements by including a third, spectrally-shifted biosensor. Our work demonstrates that exploiting donor photochromism in FRET can be a powerful approach to simultaneously read out multiple associations within living cells. Performing multiple FRET measurements at once can be challenging. Here the authors report a method to discriminate between overlapping FRET pairs, even if the fluorophores display almost identical absorption and emission spectra, based on the photochromism of the donor fluorophores.
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13
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Abreu N, Levitz J. Optogenetic Techniques for Manipulating and Sensing G Protein-Coupled Receptor Signaling. Methods Mol Biol 2021; 2173:21-51. [PMID: 32651908 DOI: 10.1007/978-1-0716-0755-8_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
G protein-coupled receptors (GPCRs) form the largest class of membrane receptors in the mammalian genome with nearly 800 human genes encoding for unique subtypes. Accordingly, GPCR signaling is implicated in nearly all physiological processes. However, GPCRs have been difficult to study due in part to the complexity of their function which can lead to a plethora of converging or diverging downstream effects over different time and length scales. Classic techniques such as pharmacological control, genetic knockout and biochemical assays often lack the precision required to probe the functions of specific GPCR subtypes. Here we describe the rapidly growing set of optogenetic tools, ranging from methods for optical control of the receptor itself to optical sensing and manipulation of downstream effectors. These tools permit the quantitative measurements of GPCRs and their downstream signaling with high specificity and spatiotemporal precision.
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Affiliation(s)
- Nohely Abreu
- Biochemistry, Cell and Molecular Biology Graduate Program, Weill Cornell Medicine, New York, NY, USA
| | - Joshua Levitz
- Biochemistry, Cell and Molecular Biology Graduate Program, Weill Cornell Medicine, New York, NY, USA.
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, USA.
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14
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Fischer LS, Rangarajan S, Sadhanasatish T, Grashoff C. Molecular Force Measurement with Tension Sensors. Annu Rev Biophys 2021; 50:595-616. [PMID: 33710908 DOI: 10.1146/annurev-biophys-101920-064756] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ability of cells to generate mechanical forces, but also to sense, adapt to, and respond to mechanical signals, is crucial for many developmental, postnatal homeostatic, and pathophysiological processes. However, the molecular mechanisms underlying cellular mechanotransduction have remained elusive for many decades, as techniques to visualize and quantify molecular forces across individual proteins in cells were missing. The development of genetically encoded molecular tension sensors now allows the quantification of piconewton-scale forces that act upon distinct molecules in living cells and even whole organisms. In this review, we discuss the physical principles, advantages, and limitations of this increasingly popular method. By highlighting current examples from the literature, we demonstrate how molecular tension sensors can be utilized to obtain access to previously unappreciated biophysical parameters that define the propagation of mechanical forces on molecular scales. We discuss how the methodology can be further developed and provide a perspective on how the technique could be applied to uncover entirely novel aspects of mechanobiology in the future.
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Affiliation(s)
- Lisa S Fischer
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Srishti Rangarajan
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Tanmay Sadhanasatish
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Carsten Grashoff
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
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15
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Keyes J, Mehta S, Zhang J. Strategies for Multiplexed Biosensor Imaging to Study Intracellular Signaling Networks. Methods Mol Biol 2021; 2350:1-20. [PMID: 34331275 PMCID: PMC8580745 DOI: 10.1007/978-1-0716-1593-5_1] [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: 03/16/2023]
Abstract
Signal transduction processes are a necessary component of multicellular life, and their dysregulation is the basis for a host of syndromes and diseases. Thus, it is imperative that we discover the complex details of how signal transduction processes result in specific cellular outcomes. One of the primary mechanisms of regulation over signaling pathways is through spatiotemporal control. However, traditional methods are limited in their ability to reveal such details. To overcome these limitations, researchers have developed a variety of genetically encodable, fluorescent protein-based biosensors to study these dynamic processes in real time in living cells. Due to the complexities and interconnectedness of signaling pathways, it is thus desirable to use multiple biosensors in individual cells to better elucidate the relationships between signaling pathways. However, multiplexed imaging with such biosensors has been historically difficult. Nevertheless, recent developments in designs and multiplexing strategies have led to vast improvements in our capabilities. In this review, we provide perspectives on the recently developed biosensor designs and multiplexing strategies that are available for multiplexed imaging of signal transduction pathways.
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Affiliation(s)
- Jeremiah Keyes
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA.
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16
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Liput DJ, Nguyen TA, Augustin SM, Lee JO, Vogel SS. A Guide to Fluorescence Lifetime Microscopy and Förster's Resonance Energy Transfer in Neuroscience. CURRENT PROTOCOLS IN NEUROSCIENCE 2020; 94:e108. [PMID: 33232577 PMCID: PMC8274369 DOI: 10.1002/cpns.108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fluorescence lifetime microscopy (FLIM) and Förster's resonance energy transfer (FRET) are advanced optical tools that neuroscientists can employ to interrogate the structure and function of complex biological systems in vitro and in vivo using light. In neurobiology they are primarily used to study protein-protein interactions, to study conformational changes in protein complexes, and to monitor genetically encoded FRET-based biosensors. These methods are ideally suited to optically monitor changes in neurons that are triggered optogenetically. Utilization of this technique by neuroscientists has been limited, since a broad understanding of FLIM and FRET requires familiarity with the interactions of light and matter on a quantum mechanical level, and because the ultra-fast instrumentation used to measure fluorescent lifetimes and resonance energy transfer are more at home in a physics lab than in a biology lab. In this overview, we aim to help neuroscientists overcome these obstacles and thus feel more comfortable with the FLIM-FRET method. Our goal is to aid researchers in the neuroscience community to achieve a better understanding of the fundamentals of FLIM-FRET and encourage them to fully leverage its powerful ability as a research tool. Published 2020. U.S. Government.
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Affiliation(s)
- Daniel J. Liput
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Tuan A. Nguyen
- Laboratory of Biophotonics and Quantum Biology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Shana M. Augustin
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Jeong Oen Lee
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Steven S. Vogel
- Laboratory of Biophotonics and Quantum Biology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
- Corresponding author:
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17
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Koveal D, Díaz-García CM, Yellen G. Fluorescent Biosensors for Neuronal Metabolism and the Challenges of Quantitation. Curr Opin Neurobiol 2020; 63:111-121. [PMID: 32559637 PMCID: PMC7646541 DOI: 10.1016/j.conb.2020.02.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 01/08/2023]
Abstract
Over the past decade, genetically encoded fluorescent biosensors that report metabolic changes have become valuable tools for understanding brain metabolism. These sensors have been targeted to specific brain regions and cell types in different organisms to track multiple metabolic processes at single cell (and subcellular) resolution. Here, we review genetically encoded biosensors used to study metabolism in the brain. We particularly focus on the principles needed to use these sensors quantitatively while avoiding false inferences from variations in sensor fluorescence that arise from differences in expression level or environmental influences such as pH or temperature.
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Affiliation(s)
- Dorothy Koveal
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Gary Yellen
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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18
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Sadoul K, Lafanechère L, Grichine A. Live imaging of single platelets at work. Platelets 2020; 31:551-558. [PMID: 31880193 DOI: 10.1080/09537104.2019.1708886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Although live imaging of dynamic processes in platelets is a challenging task, several important observations have been published during the last 20 years. We will discuss the amazing insights that have been achieved, the difficulties that can be encountered as well as some questions still open and the future technical perspectives.
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Affiliation(s)
- Karin Sadoul
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
| | - Laurence Lafanechère
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
| | - Alexei Grichine
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
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19
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Moeyaert B, Dedecker P. Genetically encoded biosensors based on innovative scaffolds. Int J Biochem Cell Biol 2020; 125:105761. [PMID: 32504671 DOI: 10.1016/j.biocel.2020.105761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 12/12/2022]
Abstract
Genetically encoded biosensors are indispensable tools for visualizing the spatiotemporal dynamics of analytes or processes in living cells in vitro and in vivo. Their widespread adaptation has gone hand in hand with the development of sensors for new analytes or processes and improved functionality and robustness. In this review, we highlight some of the recent advances in genetically encoded biosensor development, with a special focus on novel and innovative scaffolds that will lead to new possibilities in the future.
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Affiliation(s)
- Benjamien Moeyaert
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Heverlee, Belgium
| | - Peter Dedecker
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Heverlee, Belgium.
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20
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Bertolin G, Tramier M. Insights into the non-mitotic functions of Aurora kinase A: more than just cell division. Cell Mol Life Sci 2020; 77:1031-1047. [PMID: 31562563 PMCID: PMC11104877 DOI: 10.1007/s00018-019-03310-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/13/2019] [Accepted: 09/18/2019] [Indexed: 02/02/2023]
Abstract
AURKA is a serine/threonine kinase overexpressed in several cancers. Originally identified as a protein with multifaceted roles during mitosis, improvements in quantitative microscopy uncovered several non-mitotic roles as well. In physiological conditions, AURKA regulates cilia disassembly, neurite extension, cell motility, DNA replication and senescence programs. In cancer-like contexts, AURKA actively promotes DNA repair, it acts as a transcription factor, promotes cell migration and invasion, and it localises at mitochondria to regulate mitochondrial dynamics and ATP production. Here we review the non-mitotic roles of AURKA, and its partners outside of cell division. In addition, we give an insight into how structural data and quantitative fluorescence microscopy allowed to understand AURKA activation and its interaction with new substrates, highlighting future developments in fluorescence microscopy needed to better understand AURKA functions in vivo. Last, we will recapitulate the most significant AURKA inhibitors currently in clinical trials, and we will explore how the non-mitotic roles of the kinase may provide new insights to ameliorate current pharmacological strategies against AURKA overexpression.
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Affiliation(s)
- Giulia Bertolin
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000, Rennes, France.
| | - Marc Tramier
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000, Rennes, France.
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21
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Sizaire F, Le Marchand G, Pécréaux J, Bouchareb O, Tramier M. Automated screening of AURKA activity based on a genetically encoded FRET biosensor using fluorescence lifetime imaging microscopy. Methods Appl Fluoresc 2020; 8:024006. [PMID: 32032967 DOI: 10.1088/2050-6120/ab73f5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Fluorescence Lifetime Imaging Microscopy (FLIM) is a robust tool to measure Förster Resonance Energy Transfer (FRET) between two fluorescent proteins, mainly when using genetically-encoded FRET biosensors. It is then possible to monitor biological processes such as kinase activity with a good spatiotemporal resolution and accuracy. Therefore, it is of interest to improve this methodology for future high content screening purposes. We here implement a time-gated FLIM microscope that can image and quantify fluorescence lifetime with a higher speed than conventional techniques such as Time-Correlated Single Photon Counting (TCSPC). We then improve our system to perform automatic screen analysis in a 96-well plate format. Moreover, we use a FRET biosensor of AURKA activity, a mitotic kinase involved in several epithelial cancers. Our results show that our system is suitable to measure FRET within our biosensor paving the way to the screening of novel compounds, potentially allowing to find new inhibitors of AURKA activity.
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Affiliation(s)
- Florian Sizaire
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
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22
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Esposito A. How many photons are needed for FRET imaging? BIOMEDICAL OPTICS EXPRESS 2020; 11:1186-1202. [PMID: 32133242 PMCID: PMC7041441 DOI: 10.1364/boe.379305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/15/2019] [Accepted: 01/21/2020] [Indexed: 06/10/2023]
Abstract
Förster resonance energy transfer (FRET) imaging is an essential analytical method in biomedical research. The limited photon-budget experimentally available, however, imposes compromises between spatiotemporal and biochemical resolutions, photodamage and phototoxicity. The study of photon-statistics in biochemical imaging is thus important in guiding the efficient design of instrumentation and assays. Here, we show a comparative analysis of photon-statistics in FRET imaging demonstrating how the precision of FRET imaging varies vastly with imaging parameters. Therefore, we provide analytical and numerical tools for assay optimization. Fluorescence lifetime imaging microscopy (FLIM) is a very robust technique with excellent photon-efficiencies. However, we show that also intensity-based FRET imaging can reach high precision by utilizing information from both donor and acceptor fluorophores.
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Affiliation(s)
- Alessandro Esposito
- MRC Cancer Unit, University of Cambridge, Biomedical Campus, Cambridge, CB20XY, UK
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23
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24
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Castellani CM, Torres-Ocampo AP, Breffke J, White AB, Chambers JJ, Stratton MM, Maresca TJ. Live-cell FLIM-FRET using a commercially available system. Methods Cell Biol 2020; 158:63-89. [PMID: 32423651 PMCID: PMC8006575 DOI: 10.1016/bs.mcb.2020.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Förster resonance energy transfer (FRET)-based sensors have been powerful tools in cell biologists' toolkit for decades. Informed by fundamental understanding of fluorescent proteins, protein-protein interactions, and the structural biology of reporter components, researchers have been able to employ creative design approaches to build sensors that are uniquely capable of probing a wide range of phenomena in living cells including visualization of localized calcium signaling, sub-cellular activity gradients, and tension generation to name but a few. While FRET sensors have significantly impacted many fields, one must also be cognizant of the limitations to conventional, intensity-based FRET measurements stemming from variation in probe concentration, sensitivity to photobleaching, and bleed-through between the FRET fluorophores. Fluorescence lifetime imaging microscopy (FLIM) largely overcomes the limitations of intensity-based FRET measurements. In general terms, FLIM measures the time, which for the reporters described in this chapter is nanoseconds (ns), between photon absorption and emission by a fluorophore. When FLIM is applied to FRET sensors (FLIM-FRET), measurement of the donor fluorophore lifetime provides valuable information such as FRET efficiency and the percentage of reporters engaged in FRET. This chapter introduces fundamental principles of FLIM-FRET toward informing the practical application of the technique and, using two established FRET reporters as proofs of concept, outlines how to use a commercially available FLIM system.
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Affiliation(s)
| | - Ana P. Torres-Ocampo
- Department of Biochemistry & Molecular Biology, University of Massachusetts, Amherst, MA,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA
| | | | | | - James J. Chambers
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA
| | - Margaret M. Stratton
- Department of Biochemistry & Molecular Biology, University of Massachusetts, Amherst, MA,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA
| | - Thomas J. Maresca
- Biology Department, University of Massachusetts, Amherst, MA,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA
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25
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Bertolin G, Sizaire F, Déméautis C, Chapuis C, Mérola F, Erard M, Tramier M. Optimized FRET Pairs and Quantification Approaches To Detect the Activation of Aurora Kinase A at Mitosis. ACS Sens 2019; 4:2018-2027. [PMID: 31317736 DOI: 10.1021/acssensors.9b00486] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Genetically encoded Förster's Resonance Energy Transfer (FRET) biosensors are indispensable tools to sense the spatiotemporal dynamics of signal transduction pathways. Investigating the crosstalk between different signaling pathways is becoming increasingly important to follow cell development and fate programs. To this end, FRET biosensors must be optimized to monitor multiple biochemical activities simultaneously and in single cells. In addition, their sensitivity must be increased to follow their activation even when the abundance of the biosensor is low. We describe here the development of a second generation of Aurora kinase A/AURKA biosensors. First, we adapt the original AURKA biosensor-GFP-AURKA-mCherry-to multiplex FRET by using dark acceptors as ShadowG or ShadowY. Then, we use the novel superYFP acceptor protein to measure FRET by 2-color Fluorescence Cross-Correlation Spectroscopy, in cytosolic regions where the abundance of AURKA is extremely low and undetectable with the original AURKA biosensor. These results pave the way to the use of FRET biosensors to follow AURKA activation in conjunction with substrate-based activity biosensors. In addition, they open up the possibility of tracking the activation of small pools of AURKA and its interaction with novel substrates, which would otherwise remain undetectable with classical biochemical approaches.
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Affiliation(s)
- Giulia Bertolin
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
| | - Florian Sizaire
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
| | - Claire Déméautis
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
| | - Catherine Chapuis
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
| | - Fabienne Mérola
- Univ Paris Sud, CNRS, LCP (Laboratoire de Chimie Physique), UMR 800, F-91400 Orsay, France
| | - Marie Erard
- Univ Paris Sud, CNRS, LCP (Laboratoire de Chimie Physique), UMR 800, F-91400 Orsay, France
| | - Marc Tramier
- Univ Rennes, CNRS, IGDR (Genetics and Development Institute of Rennes), UMR 6290, F-35000 Rennes, France
- Univ Rennes, BIOSIT, UMS CNRS 3480, US INSERM
018, F-35000 Rennes, France
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26
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ShadowR: a novel chromoprotein with reduced non-specific binding and improved expression in living cells. Sci Rep 2019; 9:12072. [PMID: 31427680 PMCID: PMC6700193 DOI: 10.1038/s41598-019-48604-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 08/08/2019] [Indexed: 01/08/2023] Open
Abstract
Here we developed an orange light-absorbing chromoprotein named ShadowR as a novel acceptor for performing fluorescence lifetime imaging microscopy-based Förster resonance energy transfer (FLIM-FRET) measurement in living cells. ShadowR was generated by replacing hydrophobic amino acids located at the surface of the chromoprotein Ultramarine with hydrophilic amino acids in order to reduce non-specific interactions with cytosolic proteins. Similar to Ultramarine, ShadowR shows high absorption capacity and no fluorescence. However, it exhibits reduced non-specific binding to cytosolic proteins and is highly expressed in HeLa cells. Using tandem constructs and a LOVTRAP system, we showed that ShadowR can be used as a FRET acceptor in combination with donor mRuby2 or mScarlet in HeLa cells. Thus, ShadowR is a useful, novel FLIM-FRET acceptor.
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27
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Cost A, Khalaji S, Grashoff C. Genetically Encoded FRET‐Based Tension Sensors. ACTA ACUST UNITED AC 2019; 83:e85. [DOI: 10.1002/cpcb.85] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Anna‐Lena Cost
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
| | - Samira Khalaji
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
| | - Carsten Grashoff
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
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28
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Ziegler CS, Bouchab L, Tramier M, Durand D, Fieschi F, Dupré-Crochet S, Mérola F, Nüße O, Erard M. Quantitative live-cell imaging and 3D modeling reveal critical functional features in the cytosolic complex of phagocyte NADPH oxidase. J Biol Chem 2019; 294:3824-3836. [PMID: 30630949 DOI: 10.1074/jbc.ra118.006864] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/08/2019] [Indexed: 01/18/2023] Open
Abstract
Phagocyte NADPH oxidase produces superoxide anions, a precursor of reactive oxygen species (ROS) critical for host responses to microbial infections. However, uncontrolled ROS production contributes to inflammation, making NADPH oxidase a major drug target. It consists of two membranous (Nox2 and p22phox) and three cytosolic subunits (p40phox, p47phox, and p67phox) that undergo structural changes during enzyme activation. Unraveling the interactions between these subunits and the resulting conformation of the complex could shed light on NADPH oxidase regulation and help identify inhibition sites. However, the structures and the interactions of flexible proteins comprising several well-structured domains connected by intrinsically disordered protein segments are difficult to investigate by conventional techniques such as X-ray crystallography, NMR, or cryo-EM. Here, we developed an analytical strategy based on FRET-fluorescence lifetime imaging (FLIM) and fluorescence cross-correlation spectroscopy (FCCS) to structurally and quantitatively characterize NADPH oxidase in live cells. We characterized the inter- and intramolecular interactions of its cytosolic subunits by elucidating their conformation, stoichiometry, interacting fraction, and affinities in live cells. Our results revealed that the three subunits have a 1:1:1 stoichiometry and that nearly 100% of them are present in complexes in living cells. Furthermore, combining FRET data with small-angle X-ray scattering (SAXS) models and published crystal structures of isolated domains and subunits, we built a 3D model of the entire cytosolic complex. The model disclosed an elongated complex containing a flexible hinge separating two domains ideally positioned at one end of the complex and critical for oxidase activation and interactions with membrane components.
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Affiliation(s)
- Cornelia S Ziegler
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France
| | - Leïla Bouchab
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France
| | - Marc Tramier
- the Université Rennes, CNRS, Institut de Génétique et Développement de Rennes - UMR 6290, BIOSIT - UMS 3480, F-35000 Rennes, France
| | - Dominique Durand
- the Institute for Integrative Biology of the Cell, CEA, CNRS UMR 9198, Université Paris-Sud, Université Paris-Saclay, 91190 Gif-sur-Yvette, France, and
| | - Franck Fieschi
- the Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Sophie Dupré-Crochet
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France
| | - Fabienne Mérola
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France
| | - Oliver Nüße
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France,
| | - Marie Erard
- From the Laboratoire de Chimie Physique, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay France,
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29
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Greenwald EC, Mehta S, Zhang J. Genetically Encoded Fluorescent Biosensors Illuminate the Spatiotemporal Regulation of Signaling Networks. Chem Rev 2018; 118:11707-11794. [PMID: 30550275 PMCID: PMC7462118 DOI: 10.1021/acs.chemrev.8b00333] [Citation(s) in RCA: 299] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cellular signaling networks are the foundation which determines the fate and function of cells as they respond to various cues and stimuli. The discovery of fluorescent proteins over 25 years ago enabled the development of a diverse array of genetically encodable fluorescent biosensors that are capable of measuring the spatiotemporal dynamics of signal transduction pathways in live cells. In an effort to encapsulate the breadth over which fluorescent biosensors have expanded, we endeavored to assemble a comprehensive list of published engineered biosensors, and we discuss many of the molecular designs utilized in their development. Then, we review how the high temporal and spatial resolution afforded by fluorescent biosensors has aided our understanding of the spatiotemporal regulation of signaling networks at the cellular and subcellular level. Finally, we highlight some emerging areas of research in both biosensor design and applications that are on the forefront of biosensor development.
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Affiliation(s)
- Eric C Greenwald
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Sohum Mehta
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Jin Zhang
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
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30
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Kim J, Heo WD. Synergistic Ensemble of Optogenetic Actuators and Dynamic Indicators in Cell Biology. Mol Cells 2018; 41:809-817. [PMID: 30157546 PMCID: PMC6182222 DOI: 10.14348/molcells.2018.0295] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/07/2018] [Indexed: 12/13/2022] Open
Abstract
Discovery of the naturally evolved fluorescent proteins and their genetically engineered biosensors have enormously contributed to current bioimaging techniques. These reporters to trace dynamic changes of intracellular protein activities have continuously transformed according to the various demands in biological studies. Along with that, light-inducible optogenetic technologies have offered scientists to perturb, control and analyze the function of intracellular machineries in spatiotemporal manner. In this review, we present an overview of the molecular strategies that have been exploited for producing genetically encoded protein reporters and various optogenetic modules. Finally, in particular, we discuss the current efforts for combined use of these reporters and optogenetic modules as a powerful tactic for the control and imaging of signaling events in cells and tissues.
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Affiliation(s)
- Jihoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Won Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34141,
Korea
- KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
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31
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Buschhaus JM, Humphries B, Luker KE, Luker GD. A Caspase-3 Reporter for Fluorescence Lifetime Imaging of Single-Cell Apoptosis. Cells 2018; 7:cells7060057. [PMID: 30720785 PMCID: PMC6025355 DOI: 10.3390/cells7060057] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/01/2018] [Accepted: 06/08/2018] [Indexed: 11/16/2022] Open
Abstract
Fluorescence lifetime imaging (FLIM) is a powerful imaging modality used to gather fluorescent reporter data independent of intracellular reporter intensity or imaging depth. We applied this technique to image real-time activation of a reporter for the proteolytic enzyme, caspase-3, in response to apoptotic cell death. This caspase-3 reporter activity provides valuable insight into cancer cell responsiveness to therapy and overall viability at a single-cell scale. Cleavage of a aspartate-glutamate-valine-aspartate (DEVD) linkage sequence alters Förster resonance energy transfer (FRET) within the reporter, affecting its lifetime. Cellular apoptosis was quantified in multiple environments ranging from 2D flat and 3D spheroid cell culture systems to in vivo murine mammary tumor xenografts. We evaluated cell-by-cell apoptotic responses to multiple pharmacological and genetic methods of interest involved in cancer cell death. Within this article, we describe methods for measuring caspase-3 activation at single-cell resolution in various complex environments using FLIM.
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Affiliation(s)
- Johanna M Buschhaus
- Center for Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, MI 48190, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48190, USA.
| | - Brock Humphries
- Center for Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, MI 48190, USA.
| | - Kathryn E Luker
- Center for Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, MI 48190, USA.
| | - Gary D Luker
- Center for Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, MI 48190, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48190, USA.
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48190, USA.
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Shcherbakova DM, Cox Cammer N, Huisman TM, Verkhusha VV, Hodgson L. Direct multiplex imaging and optogenetics of Rho GTPases enabled by near-infrared FRET. Nat Chem Biol 2018; 14:591-600. [PMID: 29686359 PMCID: PMC5964015 DOI: 10.1038/s41589-018-0044-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 03/01/2018] [Indexed: 12/31/2022]
Abstract
Direct visualization and light control of several cellular processes is a challenge, owing to the spectral overlap of available genetically encoded probes. Here we report the most red-shifted monomeric near-infrared (NIR) fluorescent protein, miRFP720, and the fully NIR Förster resonance energy transfer (FRET) pair miRFP670-miRFP720, which together enabled design of biosensors compatible with CFP-YFP imaging and blue-green optogenetic tools. We developed a NIR biosensor for Rac1 GTPase and demonstrated its use in multiplexed imaging and light control of Rho GTPase signaling pathways. Specifically, we combined the Rac1 biosensor with CFP-YFP FRET biosensors for RhoA and for Rac1-GDI binding, and concurrently used the LOV-TRAP tool for upstream Rac1 activation. We directly observed and quantified antagonism between RhoA and Rac1 dependent on the RhoA-downstream effector ROCK; showed that Rac1 activity and GDI binding closely depend on the spatiotemporal coordination between these two molecules; and simultaneously observed Rac1 activity during optogenetic manipulation of Rac1.
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Affiliation(s)
- Daria M Shcherbakova
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Natasha Cox Cammer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Tsipora M Huisman
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA.
- Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA.
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Louis Hodgson
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA.
- Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA.
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Komis G, Šamajová O, Ovečka M, Šamaj J. Cell and Developmental Biology of Plant Mitogen-Activated Protein Kinases. ANNUAL REVIEW OF PLANT BIOLOGY 2018; 69:237-265. [PMID: 29489398 DOI: 10.1146/annurev-arplant-042817-040314] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Plant mitogen-activated protein kinases (MAPKs) constitute a network of signaling cascades responsible for transducing extracellular stimuli and decoding them to dedicated cellular and developmental responses that shape the plant body. Over the last decade, we have accumulated information about how MAPK modules control the development of reproductive tissues and gametes and the embryogenic and postembryonic development of vegetative organs such as roots, root nodules, shoots, and leaves. Of key importance to understanding how MAPKs participate in developmental and environmental signaling is the characterization of their subcellular localization, their interactions with upstream signal perception mechanisms, and the means by which they target their substrates. In this review, we summarize the roles of MAPK signaling in the regulation of key plant developmental processes, and we survey what is known about the mechanisms guiding the subcellular compartmentalization of MAPK modules.
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Affiliation(s)
- George Komis
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, 783 71 Olomouc, Czech Republic;
| | - Olga Šamajová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, 783 71 Olomouc, Czech Republic;
| | - Miroslav Ovečka
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, 783 71 Olomouc, Czech Republic;
| | - Jozef Šamaj
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, 783 71 Olomouc, Czech Republic;
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Abstract
Productive chromosome movements require that a large multiprotein complex called the kinetochore assemble on sister centromeres. The kinetochore fulfills two critical functions as (1) the physical linkage between chromosomes and spindle microtubules and (2) a mechanomolecular sensor that relays a spindle assembly checkpoint signal delaying anaphase onset until chromosomes are attached to spindle microtubules and bioriented. Given its central roles in such a vital process, the kinetochore is one of the most important force-transducing structures in cells; yet it has been technically challenging to measure kinetochore forces. Barriers to measuring cellular forces have begun to be broken by the development of fluorescence-based tension sensors. In this chapter, two methods will be described for measuring kinetochore forces in living cells and strategies for applying these sensors to other force-transducing processes and molecules will be discussed.
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Nobis M, Warren SC, Lucas MC, Murphy KJ, Herrmann D, Timpson P. Molecular mobility and activity in an intravital imaging setting - implications for cancer progression and targeting. J Cell Sci 2018; 131:131/5/jcs206995. [PMID: 29511095 DOI: 10.1242/jcs.206995] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Molecular mobility, localisation and spatiotemporal activity are at the core of cell biological processes and deregulation of these dynamic events can underpin disease development and progression. Recent advances in intravital imaging techniques in mice are providing new avenues to study real-time molecular behaviour in intact tissues within a live organism and to gain exciting insights into the intricate regulation of live cell biology at the microscale level. The monitoring of fluorescently labelled proteins and agents can be combined with autofluorescent properties of the microenvironment to provide a comprehensive snapshot of in vivo cell biology. In this Review, we summarise recent intravital microscopy approaches in mice, in processes ranging from normal development and homeostasis to disease progression and treatment in cancer, where we emphasise the utility of intravital imaging to observe dynamic and transient events in vivo We also highlight the recent integration of advanced subcellular imaging techniques into the intravital imaging pipeline, which can provide in-depth biological information beyond the single-cell level. We conclude with an outlook of ongoing developments in intravital microscopy towards imaging in humans, as well as provide an overview of the challenges the intravital imaging community currently faces and outline potential ways for overcoming these hurdles.
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Affiliation(s)
- Max Nobis
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
| | - Sean C Warren
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
| | - Morghan C Lucas
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
| | - Kendelle J Murphy
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
| | - David Herrmann
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
| | - Paul Timpson
- The Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Cancer Division, St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2010, Australia
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36
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Multiplexing molecular tension sensors reveals piconewton force gradient across talin-1. Nat Methods 2017; 14:1090-1096. [DOI: 10.1038/nmeth.4431] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 08/18/2017] [Indexed: 01/09/2023]
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Yasuda R. Biophysics of Biochemical Signaling in Dendritic Spines: Implications in Synaptic Plasticity. Biophys J 2017; 113:2152-2159. [PMID: 28866426 DOI: 10.1016/j.bpj.2017.07.029] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/12/2017] [Accepted: 07/20/2017] [Indexed: 11/24/2022] Open
Abstract
Dendritic spines are mushroom-shaped postsynaptic compartments that host biochemical signal cascades important for synaptic plasticity and, ultimately, learning and memory. Signaling events in spines involve a signaling network composed of hundreds of signaling proteins interacting with each other extensively. Synaptic plasticity is typically induced by Ca2+ elevation in spines, which activates a variety of signaling pathways. This leads to changes in the actin cytoskeleton and membrane dynamics, which in turn causes structural and functional changes of the spine. Recent studies have demonstrated that the activities of these proteins have a variety of spatiotemporal patterns, which orchestrate signaling activity in different subcellular compartments at different timescales. The diffusion and the decay kinetics of signaling molecules play important roles in determining the degree of their spatial spreading, and thereby the degree of the spine specificity of the signaling pathway.
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Affiliation(s)
- Ryohei Yasuda
- Max Planck Florida Institute for Neuroscience, Jupiter, Florida.
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