1
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Alonso MT, Torres-Vidal P, Calvo B, Rodriguez C, Delrio-Lorenzo A, Rojo-Ruiz J, Garcia-Sancho J, Patel S. Use of aequorin-based indicators for monitoring Ca 2+ in acidic organelles. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119481. [PMID: 37142127 DOI: 10.1016/j.bbamcr.2023.119481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/22/2023] [Accepted: 04/26/2023] [Indexed: 05/06/2023]
Abstract
Over the last years, there is accumulating evidence that acidic organelles can accumulate and release Ca2+ upon cell activation. Hence, reliable recording of Ca2+ dynamics in these compartments is essential for understanding the physiopathological aspects of acidic organelles. Genetically encoded Ca2+ indicators (GECIs) are valuable tools to monitor Ca2+ in specific locations, although their use in acidic compartments is challenging due to the pH sensitivity of most available fluorescent GECIs. By contrast, bioluminescent GECIs have a combination of features (marginal pH sensitivity, low background, no phototoxicity, no photobleaching, high dynamic range and tunable affinity) that render them advantageous to achieve an enhanced signal-to-noise ratio in acidic compartments. This article reviews the use of bioluminescent aequorin-based GECIs targeted to acidic compartments. A need for more measurements in highly acidic compartments is identified.
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Affiliation(s)
- M T Alonso
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain.
| | - P Torres-Vidal
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain
| | - B Calvo
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain
| | - C Rodriguez
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain
| | - A Delrio-Lorenzo
- Universidad Alfonso X el Sabio, Madrid, Avenida Universidad, 1, 28691 Villanueva de la Cañada, Madrid, Spain
| | - J Rojo-Ruiz
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain
| | - J Garcia-Sancho
- Unidad de Excelencia, Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), c/ Sanz y Forés 3, 47003 Valladolid, Spain
| | - S Patel
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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2
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Tian X, Zhang Y, Li X, Xiong Y, Wu T, Ai HW. A luciferase prosubstrate and a red bioluminescent calcium indicator for imaging neuronal activity in mice. Nat Commun 2022; 13:3967. [PMID: 35803917 PMCID: PMC9270435 DOI: 10.1038/s41467-022-31673-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/28/2022] [Indexed: 01/25/2023] Open
Abstract
Although fluorescent indicators have been broadly utilized for monitoring bioactivities, fluorescence imaging, when applied to mammals, is limited to superficial targets or requires invasive surgical procedures. Thus, there is emerging interest in developing bioluminescent indicators for noninvasive mammalian imaging. Bioluminescence imaging (BLI) of neuronal activity is highly desired but hindered by insufficient photons needed to digitalize fast brain activities. In this work, we develop a luciferase prosubstrate deliverable at an increased dose and activated in vivo by nonspecific esterase. We further engineer a bright, bioluminescent indicator with robust responsiveness to calcium ions (Ca2+) and appreciable emission above 600 nm. Integration of these advantageous components enables the imaging of the activity of neuronal ensembles in awake mice minimally invasively with excellent signal-to-background and subsecond temporal resolution. This study thus establishes a paradigm for studying brain function in health and disease.
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Affiliation(s)
- Xiaodong Tian
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA
| | - Yiyu Zhang
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA
| | - Xinyu Li
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA ,grid.411643.50000 0004 1761 0411Present Address: State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Ying Xiong
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA
| | - Tianchen Wu
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA
| | - Hui-Wang Ai
- grid.27755.320000 0000 9136 933XDepartment of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XCenter for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22908 USA ,grid.27755.320000 0000 9136 933XThe UVA Comprehensive Cancer Center, University of Virginia, Charlottesville, VA 22908 USA
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3
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Gagnot G, Hervin V, Coutant EP, Goyard S, Jacob Y, Rose T, Hibti FE, Quatela A, Janin YL. Core-Modified Coelenterazine Luciferin Analogues: Synthesis and Chemiluminescence Properties. Chemistry 2021; 27:2112-2123. [PMID: 33137225 DOI: 10.1002/chem.202004311] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/26/2020] [Indexed: 11/10/2022]
Abstract
In this work on the design and studies of luciferins related to the blue-hued coelenterazine, the synthesis of heterocyclic analogues susceptible to produce a photon, possibly at a different wavelength, is undertaken. Here, the synthesis of O-acetylated derivatives of imidazo[1,2-b]pyridazin-3(5 H)-one, imidazo[2,1-f][1,2,4]triazin-7(1 H)-one, imidazo[1,2-a]pyridin-3-ol, imidazo[1,2-a]quinoxalin-1(5 H)-one, benzo[f]imidazo[1,2-a]quinoxalin-3(11 H)-one, imidazo[1',2':1,6]pyrazino[2,3-c]quinolin-3(11 H)-one, and 5,11-dihydro-3 H-chromeno[4,3-e]imidazo[1,2-a]pyrazin-3-one is described thanks to extensive use of the Buchwald-Hartwig N-arylation reaction. The acidic hydrolysis of these derivatives then gave solutions of the corresponding luciferin analogues, which were studied. Not too unexpectedly, even if these were "dressed" with substituents found in actual substrates of the nanoKAZ/NanoLuc luciferase, no bioluminescence was observed with these compounds. However, in a phosphate buffer, all produced a light signal, by chemiluminescence, with extensive variations in their respective intensity and this could be increased by adding a quaternary ammonium salt in the buffer. This aspect was actually instrumental to determine the emission spectra of many of these luciferin analogues.
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Affiliation(s)
- Glwadys Gagnot
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France.,Université de Paris, 12 rue de l'école de Médecine, 75006, Paris, France
| | - Vincent Hervin
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Eloi P Coutant
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Sophie Goyard
- Center for Innovation and Technological Research, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Yves Jacob
- Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, UMR 3569, CNRS, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Thierry Rose
- Center for Innovation and Technological Research, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Fatima Ezzahra Hibti
- HORIBA FRANCE SAS, 14 Boulevard Thomas Gobert, Passage Jobin Yvon CS45002, 91120, Palaiseau, France
| | - Alessia Quatela
- HORIBA FRANCE SAS, 14 Boulevard Thomas Gobert, Passage Jobin Yvon CS45002, 91120, Palaiseau, France
| | - Yves L Janin
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
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4
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RedquorinXS Mutants with Enhanced Calcium Sensitivity and Bioluminescence Output Efficiently Report Cellular and Neuronal Network Activities. Int J Mol Sci 2020; 21:ijms21217846. [PMID: 33105848 PMCID: PMC7660078 DOI: 10.3390/ijms21217846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 01/14/2023] Open
Abstract
Considerable efforts have been focused on shifting the wavelength of aequorin Ca2+-dependent blue bioluminescence through fusion with fluorescent proteins. This approach has notably yielded the widely used GFP-aequorin (GA) Ca2+ sensor emitting green light, and tdTomato-aequorin (Redquorin), whose bioluminescence is completely shifted to red, but whose Ca2+ sensitivity is low. In the present study, the screening of aequorin mutants generated at twenty-four amino acid positions in and around EF-hand Ca2+-binding domains resulted in the isolation of six aequorin single or double mutants (AequorinXS) in EF2, EF3, and C-terminal tail, which exhibited markedly higher Ca2+ sensitivity than wild-type aequorin in vitro. The corresponding Redquorin mutants all showed higher Ca2+ sensitivity than wild-type Redquorin, and four of them (RedquorinXS) matched the Ca2+ sensitivity of GA in vitro. RedquorinXS mutants exhibited unaltered thermostability and peak emission wavelengths. Upon stable expression in mammalian cell line, all RedquorinXS mutants reported the activation of the P2Y2 receptor by ATP with higher sensitivity and assay robustness than wt-Redquorin, and one, RedquorinXS-Q159T, outperformed GA. Finally, wide-field bioluminescence imaging in mouse neocortical slices showed that RedquorinXS-Q159T and GA similarly reported neuronal network activities elicited by the removal of extracellular Mg2+. Our results indicate that RedquorinXS-Q159T is a red light-emitting Ca2+ sensor suitable for the monitoring of intracellular signaling in a variety of applications in cells and tissues, and is a promising candidate for the transcranial monitoring of brain activities in living mice.
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5
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Luo J, Chen L, Huang F, Gao P, Zhao H, Wang Y, Han S. Intraorganellar calcium imaging in Arabidopsis seedling roots using the GCaMP variants GCaMP6m and R-CEPIA1er. JOURNAL OF PLANT PHYSIOLOGY 2020; 246-247:153127. [PMID: 32007728 DOI: 10.1016/j.jplph.2020.153127] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/14/2020] [Accepted: 01/14/2020] [Indexed: 05/26/2023]
Abstract
Ca2+ acts as a universal second messenger in eukaryotes. In animals, a wide variety of environmental and developmental stimuli trigger Ca2+ dynamics in organelles, such as the cytoplasm, nucleus, and endoplasmic reticulum (ER). However, ER Ca2+ ([Ca2+]er) homeostasis and its contributions in cytosolic and/or nucleosolic Ca2+ dynamics in plants remain elusive. GCaMPs are comprised of a circularly permutated form of enhanced green fluorescent protein fused to calmodulin and myosin light-chain kinase M13 and used for monitoring Ca2+ dynamics in mammalian cells. Here, we targeted a high-affinity variant of GCaMP with nuclear export signal in the cytoplasm (NES-GCaMP6m), with a nuclear-localised signal in the nucleus (NLS-GCaMP6m), and a low-affinity variant of GCaMP, also known as calcium-measuring organelle-entrapped protein indicators (CEPIA), with a signal peptide sequence of the ER-localised protein Calreticulin 1a in the ER lumen (CRT1a-R-CEPIA1er) for intraorganellar Ca2+ imaging in Arabidopsis. We found that cytosolic Ca2+ ([Ca2+]cyt) increases induced by 250 mM sorbitol as an osmotic stress stimulus, 50 μM abscisic acid (ABA), or 1 mM carbachol (CCh) were mainly due to extracellular Ca2+ influx, whereas nucleosolic Ca2+ ([Ca2+]nuc) increases triggered by osmotic stress, ABA, or CCh were contributed by [Ca2+]er release. In addition, [Ca2+]er dynamics presented specific patterns in response to different stimuli such as osmotic stress, ABA, or CCh, indicating that Ca2+ signalling occurs in the ER in plants. These results provide valuable insights into subcellular Ca2+ dynamics in response to different stresses in Arabidopsis root cells and prove that GCaMP imaging is a useful tool for furthering our understanding of plant organelle functions.
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Affiliation(s)
- Jin Luo
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Lvli Chen
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Feifei Huang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Ping Gao
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Heping Zhao
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Yingdian Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Shengcheng Han
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
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6
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Coutant EP, Gagnot G, Hervin V, Baatallah R, Goyard S, Jacob Y, Rose T, Janin YL. Bioluminescence Profiling of NanoKAZ/NanoLuc Luciferase Using a Chemical Library of Coelenterazine Analogues. Chemistry 2020; 26:948-958. [PMID: 31765054 DOI: 10.1002/chem.201904844] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Indexed: 12/11/2022]
Abstract
We describe here an extensive structure-bioluminescence relationship study of a chemical library of analogues of coelenterazine, using nanoKAZ/NanoLuc, a mutated luciferase originated from the catalytic subunit of the deep-sea shrimp Oplophorus gracilirostris. Out of the 135 O-acetylated precursors that were prepared by using our recently reported synthesis and following their hydrolysis to give solutions of the corresponding luciferins, notable bioluminescence improvements were achieved in comparison with furimazine, which is currently amongst the best substrates of nanoKAZ/NanoLuc. For instance, the rather more lipophilic analogue 8-(2,3-difluorobenzyl)-2-((5-methylfuran-2-yl)methyl)-6-phenylimidazo[1,2-a]pyrazin-3(7H)-one provided a 1.5-fold improvement of the total light output over a 2 h period, a close to threefold increase of the initial signal intensity and a signal-to-background ratio five times greater than furimazine. The kinetic parameters for the enzymatic reaction were obtained for a selection of luciferin analogues and provided unexpected insights into the luciferase activity. Most prominently, along with a general substrate-dependent and irreversible inactivation of this enzyme, in the case of the optimized luciferin mentioned above, the consumption of 2664 molecules was found to be required for the detection of a single Relative Light Unit (RLU; a luminometer-dependent fraction of a photon).
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Affiliation(s)
- Eloi P Coutant
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Glwadys Gagnot
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France.,Université Paris Descartes, Sorbonne Paris Cité, 12 rue de l'Ecole de Médecine, 75006, Paris, France
| | - Vincent Hervin
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Racha Baatallah
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Sophie Goyard
- Center for Innovation and Technological Research, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Yves Jacob
- Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, UMR 3569, CNRS, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Thierry Rose
- Center for Innovation and Technological Research, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France
| | - Yves L Janin
- Institut Pasteur, UMR 3523, CNRS, Unité de Chimie et Biocatalyse, 28 rue du Dr. Roux, 75724, Paris Cedex 15, France
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7
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Bhuckory S, Kays JC, Dennis AM. In Vivo Biosensing Using Resonance Energy Transfer. BIOSENSORS 2019; 9:E76. [PMID: 31163706 PMCID: PMC6628364 DOI: 10.3390/bios9020076] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 05/20/2019] [Accepted: 05/27/2019] [Indexed: 01/05/2023]
Abstract
Solution-phase and intracellular biosensing has substantially enhanced our understanding of molecular processes foundational to biology and pathology. Optical methods are favored because of the low cost of probes and instrumentation. While chromatographic methods are helpful, fluorescent biosensing further increases sensitivity and can be more effective in complex media. Resonance energy transfer (RET)-based sensors have been developed to use fluorescence, bioluminescence, or chemiluminescence (FRET, BRET, or CRET, respectively) as an energy donor, yielding changes in emission spectra, lifetime, or intensity in response to a molecular or environmental change. These methods hold great promise for expanding our understanding of molecular processes not just in solution and in vitro studies, but also in vivo, generating information about complex activities in a natural, organismal setting. In this review, we focus on dyes, fluorescent proteins, and nanoparticles used as energy transfer-based optical transducers in vivo in mice; there are examples of optical sensing using FRET, BRET, and in this mammalian model system. After a description of the energy transfer mechanisms and their contribution to in vivo imaging, we give a short perspective of RET-based in vivo sensors and the importance of imaging in the infrared for reduced tissue autofluorescence and improved sensitivity.
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Affiliation(s)
- Shashi Bhuckory
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
| | - Joshua C Kays
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
| | - Allison M Dennis
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
- Division of Materials Science and Engineering, Boston University, Boston, MA 02215, USA.
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8
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Tricoire L, Drobac E, Tsuzuki K, Gallopin T, Picaud S, Cauli B, Rossier J, Lambolez B. Bioluminescence calcium imaging of network dynamics and their cholinergic modulation in slices of cerebral cortex from male rats. J Neurosci Res 2019; 97:414-432. [PMID: 30604494 DOI: 10.1002/jnr.24380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/27/2018] [Accepted: 12/11/2018] [Indexed: 12/12/2022]
Abstract
The activity of neuronal ensembles was monitored in neocortical slices from male rats using wide-field bioluminescence imaging of a calcium sensor formed with the fusion of green fluorescent protein and aequorin (GA) and expressed through viral transfer. GA expression was restricted to pyramidal neurons and did not conspicuously alter neuronal morphology or neocortical cytoarchitecture. Removal of extracellular magnesium or addition of GABA receptor antagonists triggered epileptiform flashes of variable amplitude and spatial extent, indicating that the excitatory and inhibitory networks were functionally preserved in GA-expressing slices. We found that agonists of muscarinic acetylcholine receptors largely increased the peak bioluminescence response to local electrical stimulation in layer I or white matter, and gave rise to a slowly decaying response persisting for tens of seconds. The peak increase involved layers II/III and V and did not result in marked alteration of response spatial properties. The persistent response involved essentially layer V and followed the time course of the muscarinic afterdischarge depolarizing plateau in layer V pyramidal cells. This plateau potential triggered spike firing in layer V, but not layer II/III pyramidal cells, and was accompanied by recurrent synaptic excitation in layer V. Our results indicate that wide-field imaging of GA bioluminescence is well suited to monitor local and global network activity patterns, involving different mechanisms of intracellular calcium increase, and occurring on various timescales.
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Affiliation(s)
- Ludovic Tricoire
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Estelle Drobac
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Keisuke Tsuzuki
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Thierry Gallopin
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Sandrine Picaud
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Bruno Cauli
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Jean Rossier
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
| | - Bertrand Lambolez
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), INSERM, CNRS, Sorbonne Universités, Paris, France
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9
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Bakayan A, Domingo B, Vaquero CF, Peyriéras N, Llopis J. Fluorescent Protein-photoprotein Fusions and Their Applications in Calcium Imaging. Photochem Photobiol 2017; 93:448-465. [PMID: 27925224 DOI: 10.1111/php.12682] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 09/19/2016] [Indexed: 12/21/2022]
Abstract
Calcium-activated photoproteins, such as aequorin, have been used as luminescent Ca2+ indicators since 1967. After the cloning of aequorin in 1985, microinjection was substituted by its heterologous expression, which opened the way for a widespread use. Molecular fusion of green fluorescent protein (GFP) to aequorin recapitulated the nonradiative energy transfer process that occurs in the jellyfish Aequorea victoria, from which these two proteins were obtained, resulting in an increase of light emission and a shift to longer wavelength. The abundance and location of the chimera are seen by fluorescence, whereas its luminescence reports Ca2+ levels. GFP-aequorin is broadly used in an increasing number of studies, from organelles and cells to intact organisms. By fusing other fluorescent proteins to aequorin, the available luminescence color palette has been expanded for multiplexing assays and for in vivo measurements. In this report, we will attempt to review the various photoproteins available, their reported fusions with fluorescent proteins and their biological applications to image Ca2+ dynamics in organelles, cells, tissue explants and in live organisms.
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Affiliation(s)
- Adil Bakayan
- BioEmergences Unit (CNRS, USR3695), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Beatriz Domingo
- Centro Regional de Investigaciones Biomédicas (CRIB) and Facultad de Medicina de Albacete, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Cecilia F Vaquero
- Centro Regional de Investigaciones Biomédicas (CRIB) and Facultad de Medicina de Albacete, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Nadine Peyriéras
- BioEmergences Unit (CNRS, USR3695), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Juan Llopis
- Centro Regional de Investigaciones Biomédicas (CRIB) and Facultad de Medicina de Albacete, Universidad de Castilla-La Mancha, Albacete, Spain
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10
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Alonso MT, Rojo-Ruiz J, Navas-Navarro P, Rodríguez-Prados M, García-Sancho J. Measuring Ca 2+ inside intracellular organelles with luminescent and fluorescent aequorin-based sensors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:894-899. [PMID: 27939433 DOI: 10.1016/j.bbamcr.2016.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 12/05/2016] [Accepted: 12/06/2016] [Indexed: 02/06/2023]
Abstract
GFP-Aequorin Protein (GAP) can be used to measure [Ca2+] inside intracellular organelles, both by luminescence and by fluorescence. The low-affinity variant GAP3 is adequate for ratiometric imaging in the endoplasmic reticulum and Golgi apparatus, and it can be combined with conventional synthetic indicators for simultaneous measurements of cytosolic Ca2+. GAP is bioorthogonal as it does not have mammalian homologues, and it is robust and functionally expressed in transgenic flies and mice, where it can be used for Ca2+ measurements ex vivo and in vivo to explore animal models of health and disease. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- María Teresa Alonso
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), C/Sanz y Forés 3, 47003, Valladolid, Spain.
| | - Jonathan Rojo-Ruiz
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), C/Sanz y Forés 3, 47003, Valladolid, Spain
| | - Paloma Navas-Navarro
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), C/Sanz y Forés 3, 47003, Valladolid, Spain
| | - Macarena Rodríguez-Prados
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), C/Sanz y Forés 3, 47003, Valladolid, Spain
| | - Javier García-Sancho
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), C/Sanz y Forés 3, 47003, Valladolid, Spain.
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11
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Zare-Shahabadi A, Ataei A, Rezaei N. Proteins brighten the brain. Life Sci 2016; 167:1-5. [DOI: 10.1016/j.lfs.2016.10.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 10/09/2016] [Accepted: 10/21/2016] [Indexed: 01/04/2023]
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12
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Grinstead KM, Rowe L, Ensor CM, Joel S, Daftarian P, Dikici E, Zingg JM, Daunert S. Red-Shifted Aequorin Variants Incorporating Non-Canonical Amino Acids: Applications in In Vivo Imaging. PLoS One 2016; 11:e0158579. [PMID: 27367859 PMCID: PMC4930207 DOI: 10.1371/journal.pone.0158579] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 06/17/2016] [Indexed: 11/18/2022] Open
Abstract
The increased importance of in vivo diagnostics has posed new demands for imaging technologies. In that regard, there is a need for imaging molecules capable of expanding the applications of current state-of-the-art imaging in vivo diagnostics. To that end, there is a desire for new reporter molecules capable of providing strong signals, are non-toxic, and can be tailored to diagnose or monitor the progression of a number of diseases. Aequorin is a non-toxic photoprotein that can be used as a sensitive marker for bioluminescence in vivo imaging. The sensitivity of aequorin is due to the fact that bioluminescence is a rare phenomenon in nature and, therefore, it does not suffer from autofluorescence, which contributes to background emission. Emission of bioluminescence in the blue-region of the spectrum by aequorin only occurs when calcium, and its luciferin coelenterazine, are bound to the protein and trigger a biochemical reaction that results in light generation. It is this reaction that endows aequorin with unique characteristics, making it ideally suited for a number of applications in bioanalysis and imaging. Herein we report the site-specific incorporation of non-canonical or non-natural amino acids and several coelenterazine analogues, resulting in a catalog of 72 cysteine-free, aequorin variants which expand the potential applications of these photoproteins by providing several red-shifted mutants better suited to use in vivo. In vivo studies in mouse models using the transparent tissue of the eye confirmed the activity of the aequorin variants incorporating L-4-iodophehylalanine and L-4-methoxyphenylalanine after injection into the eye and topical addition of coelenterazine. The signal also remained localized within the eye. This is the first time that aequorin variants incorporating non-canonical amino acids have shown to be active in vivo and useful as reporters in bioluminescence imaging.
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Affiliation(s)
- Kristen M. Grinstead
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
| | - Laura Rowe
- Department of Chemistry, 1610 Campus Drive East, Valparaiso University, Valparaiso, IN, 46385, United States of America
| | - Charles M. Ensor
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536, United States of America
| | - Smita Joel
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
| | - Pirouz Daftarian
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
| | - Emre Dikici
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
| | - Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, R. Bunn Gautier Bldg., 1011 NW 15th Street, Miller School of Medicine, University of Miami, Miami, FL, 33136, United States of America
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13
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Dugué GP, Tricoire L. [Principles and applications of optogenetics in neuroscience]. Med Sci (Paris) 2015; 31:291-303. [PMID: 25855283 DOI: 10.1051/medsci/20153103015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Numerous achievements in biology have resulted from the evolution of biophotonics, a general term describing the use of light in the study of living systems. Over the last fifteen years, biophotonics has progressively blended with molecular genetics to give rise to optogenetics, a set of techniques enabling the functional study of genetically-defined cellular populations, compartments or processes with optical methods. In neuroscience, optogenetics allows real-time monitoring and control of the activity of specific neuronal populations in a wide range of animal models. This technical breakthrough provides a new level of sophistication in experimental approaches in the field of fundamental neuroscience, significantly enhancing our ability to understand the complexity of neuronal circuits.
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Affiliation(s)
- Guillaume P Dugué
- CNRS UMR 8197, Inserm U1024, IBENS S4.9, 46, rue d'Ulm, 75005 Paris, France
| | - Ludovic Tricoire
- CNRS UMR 8246, Inserm U1130, université Pierre et Marie Curie UM CR119, 9, quai Saint Bernard, 75005 Paris, France
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14
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Ottolini D, Calì T, Brini M. Methods to measure intracellular Ca(2+) fluxes with organelle-targeted aequorin-based probes. Methods Enzymol 2015; 543:21-45. [PMID: 24924126 DOI: 10.1016/b978-0-12-801329-8.00002-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The photoprotein aequorin generates blue light upon binding of Ca(2+) ions. Together with its very low Ca(2+)-buffering capacity and the possibility to add specific targeting sequences, this property has rendered aequorin particularly suitable to monitor Ca(2+) concentrations in specific subcellular compartments. Recently, a new generation of genetically encoded Ca(2+) probes has been developed by fusing Ca(2+)-responsive elements with the green fluorescent protein (GFP). Aequorin has also been employed to this aim, resulting in an aequorin-GFP chimera with the Ca(2+) sensitivity of aequorin and the fluorescent properties of GFP. This setup has actually solved the major limitation of aequorin, for example, its poor ability to emit light, which rendered it inappropriate for the monitoring of Ca(2+) waves at the single-cell level by imaging. In spite of the numerous genetically encoded Ca(2+) indicators that are currently available, aequorin-based probes remain the method of election when an accurate quantification of Ca(2+) levels is required. Here, we describe currently available aequorin variants and their use for monitoring Ca(2+) waves in specific subcellular compartments. Among various applications, this method is relevant for the study of the alterations of Ca(2+) homeostasis that accompany oncogenesis, tumor progression, and response to therapy.
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Affiliation(s)
- Denis Ottolini
- Department of Biology, University of Padova, Padova, Italy
| | - Tito Calì
- Department of Biology, University of Padova, Padova, Italy
| | - Marisa Brini
- Department of Biology, University of Padova, Padova, Italy.
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15
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Bakayan A, Domingo B, Miyawaki A, Llopis J. Imaging Ca(2+) activity in mammalian cells and zebrafish with a novel red-emitting aequorin variant. Pflugers Arch 2014; 467:2031-42. [PMID: 25355614 PMCID: PMC4537489 DOI: 10.1007/s00424-014-1639-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/15/2014] [Accepted: 10/21/2014] [Indexed: 02/04/2023]
Abstract
Ca2+ monitoring with aequorin is an established bioluminescence technique, whereby the photoprotein emits blue light when it binds to Ca2+. However, aequorin’s blue emission and low quantum yield limit its application for in vivo imaging because blue-green light is greatly attenuated in animal tissues. In earlier work, aequorin was molecularly fused with green, yellow, and red fluorescent proteins, producing an emission shift through bioluminescence resonance energy transfer (BRET). We have previously shown that the chimera tandem dimer Tomato-aequorin (tdTA) emits red light in mammalian cells and across the skin and other tissues of mice [1]. In this work, we varied the configuration of the linker in tdTA to maximize energy transfer. One variant, named Redquorin, improved BRET from aequorin to tdTomato to almost a maximum value, and the emission above 575 nm exceeded 73 % of total counts. By pairing Redquorin with appropriate synthetic coelenterazines, agonist-induced and spontaneous Ca2+ oscillations in single HEK-293 cells were imaged. In addition, we also imaged Ca2+ transients associated with twitching behavior in developing zebrafish embryos expressing Redquorin during the segmentation period. Furthermore, the emission profile of Redquorin resulted in significant luminescence crossing a blood sample, a highly absorbing tissue. This new tool will facilitate in vivo imaging of Ca2+ from deep tissues of animals.
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Affiliation(s)
- Adil Bakayan
- Centro Regional de Investigaciones Biomédicas (CRIB) and Facultad de Medicina de Albacete, Universidad Castilla-La Mancha, C/ Almansa 14, 02008, Albacete, Spain
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16
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Bioluminescent properties of obelin and aequorin with novel coelenterazine analogues. Anal Bioanal Chem 2014; 406:2695-707. [DOI: 10.1007/s00216-014-7656-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/28/2013] [Accepted: 01/23/2014] [Indexed: 10/25/2022]
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17
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Webb SE, Karplus E, Miller AL. Retrospective on the development of aequorin and aequorin-based imaging to visualize changes in intracellular free [Ca2+]. Mol Reprod Dev 2014; 82:563-86. [DOI: 10.1002/mrd.22298] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 12/26/2013] [Indexed: 12/17/2022]
Affiliation(s)
- Sarah E. Webb
- Division of Life Science and State Key Laboratory of Molecular Neuroscience; The Hong Kong University of Science and Technology; Kowloon Hong Kong
| | | | - Andrew L. Miller
- Division of Life Science and State Key Laboratory of Molecular Neuroscience; The Hong Kong University of Science and Technology; Kowloon Hong Kong
- Marine Biological Laboratory; Woods Hole Massachusetts
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18
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Tricoire L, Lambolez B. Neuronal network imaging in acute slices using Ca2+ sensitive bioluminescent reporter. Methods Mol Biol 2014; 1098:33-45. [PMID: 24166366 DOI: 10.1007/978-1-62703-718-1_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Genetically encoded indicators are valuable tools to study intracellular signaling cascades in real time using fluorescent or bioluminescent imaging techniques. Imaging of Ca(2+) indicators is widely used to record transient intracellular Ca(2+) increases associated with bioelectrical activity. The natural bioluminescent Ca(2+) sensor aequorin has been historically the first Ca(2+) indicator used to address biological questions. Aequorin imaging offers several advantages over fluorescent reporters: it is virtually devoid of background signal; it does not require light excitation and interferes little with intracellular processes. Genetically encoded sensors such as aequorin are commonly used in dissociated cultured cells; however it becomes more challenging to express them in differentiated intact specimen such as brain tissue. Here we describe a method to express a GFP-aequorin (GA) fusion protein in pyramidal cells of neocortical acute slices using recombinant Sindbis virus. This technique allows expressing GA in several hundreds of neurons on the same slice and to perform the bioluminescence recording of Ca(2+) transients in single neurons or multiple neurons simultaneously.
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Affiliation(s)
- Ludovic Tricoire
- Neurobiologie des processus adaptatifs, UMR7102, Université Pierre et Marie Curie, Paris, France
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19
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Genetically encoded Ca(2+) indicators: properties and evaluation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:1787-97. [PMID: 23352808 DOI: 10.1016/j.bbamcr.2013.01.011] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 01/02/2013] [Accepted: 01/10/2013] [Indexed: 02/04/2023]
Abstract
Genetically encoded calcium ion (Ca(2+)) indicators have become very useful and widely used tools for Ca(2+) imaging, not only in cellular models, but also in living organisms. However, the in vivo and in situ characterization of these indicators is tedious and time consuming, and it does not provide information regarding the suitability of an indicator for particular experimental environments. Thus, initial in vitro evaluation of these tools is typically performed to determine their properties. In this review, we examined the properties of dynamic range, affinity, selectivity, and kinetics for Ca(2+) indicators. Commonly used strategies for evaluating these properties are presented. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.
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20
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Brunner JM, Plattet P, Doucey MA, Rosso L, Curie T, Montagner A, Wittek R, Vandelvelde M, Zurbriggen A, Hirling H, Desvergne B. Morbillivirus glycoprotein expression induces ER stress, alters Ca2+ homeostasis and results in the release of vasostatin. PLoS One 2012; 7:e32803. [PMID: 22403712 PMCID: PMC3293893 DOI: 10.1371/journal.pone.0032803] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 02/04/2012] [Indexed: 11/26/2022] Open
Abstract
Although the pathology of Morbillivirus in the central nervous system (CNS) is well described, the molecular basis of neurodegenerative events still remains poorly understood. As a model to explore Morbillivirus-mediated CNS dysfunctions, we used canine distemper virus (CDV) that we inoculated into two different cell systems: a monkey cell line (Vero) and rat primary hippocampal neurons. Importantly, the recombinant CDV used in these studies not only efficiently infects both cell types but recapitulates the uncommon, non-cytolytic cell-to-cell spread mediated by virulent CDVs in brain of dogs. Here, we demonstrated that both CDV surface glycoproteins (F and H) markedly accumulated in the endoplasmic reticulum (ER). This accumulation triggered an ER stress, characterized by increased expression of the ER resident chaperon calnexin and the proapoptotic transcription factor CHOP/GADD 153. The expression of calreticulin (CRT), another ER resident chaperon critically involved in the response to misfolded proteins and in Ca(2+) homeostasis, was also upregulated. Transient expression of recombinant CDV F and H surface glycoproteins in Vero cells and primary hippocampal neurons further confirmed a correlation between their accumulation in the ER, CRT upregulation, ER stress and disruption of ER Ca(2+) homeostasis. Furthermore, CDV infection induced CRT fragmentation with re-localisation of a CRT amino-terminal fragment, also known as vasostatin, on the surface of infected and neighbouring non-infected cells. Altogether, these results suggest that ER stress, CRT fragmentation and re-localization on the cell surface may contribute to cytotoxic effects and ensuing cell dysfunctions triggered by Morbillivirus, a mechanism that might potentially be relevant for other neurotropic viruses.
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Affiliation(s)
- Jean-Marc Brunner
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
- Institut de Biotechnologie, University of Lausanne, Lausanne, Switzerland
| | - Philippe Plattet
- Department of Clinical Research and Veterinary Public Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Marie-Agnès Doucey
- Division of Experimental Oncology, Multidisciplinary Oncology Center, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
| | - Lia Rosso
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Thomas Curie
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Alexandra Montagner
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Riccardo Wittek
- Institut de Biotechnologie, University of Lausanne, Lausanne, Switzerland
| | - Marc Vandelvelde
- Department of Clinical Research and Veterinary Public Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Andreas Zurbriggen
- Department of Clinical Research and Veterinary Public Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Harald Hirling
- Brain Mind Institute, Faculté des Sciences de la Vie, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne, Switzerland
| | - Béatrice Desvergne
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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21
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Russell JT. Imaging calcium signals in vivo: a powerful tool in physiology and pharmacology. Br J Pharmacol 2012; 163:1605-25. [PMID: 20718728 DOI: 10.1111/j.1476-5381.2010.00988.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The design and engineering of organic fluorescent Ca(2+) indicators approximately 30 years ago opened the door for imaging cellular Ca(2+) signals with a high degree of temporal and spatial resolution. Over this time, Ca(2+) imaging has revolutionized our approaches for tissue-level spatiotemporal analysis of functional organization and has matured into a powerful tool for in situ imaging of cellular activity in the living animal. In vivo Ca(2+) imaging with temporal resolution at the millisecond range and spatial resolution at micrometer range has been achieved through novel designs of Ca(2+) sensors, development of modern microscopes and powerful imaging techniques such as two-photon microscopy. Imaging Ca(2+) signals in ensembles of cells within tissue in 3D allows for analysis of integrated cellular function, which, in the case of the brain, enables recording activity patterns in local circuits. The recent development of miniaturized compact, fibre-optic-based, mechanically flexible microendoscopes capable of two-photon microscopy opens the door for imaging activity in awake, behaving animals. This development is poised to open a new chapter in physiological experiments and for pharmacological approaches in the development of novel therapies.
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Affiliation(s)
- James T Russell
- Section on Cell Biology and Signal Transduction, Laboratory of Cellular and Molecular Neurophysiology, National Institute of Child Health and Human Development/NIH, 49 Convent Drive, Bethesda, MD 20892-4480, USA.
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22
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Webb SE, Miller AL. Aequorin-based genetic approaches to visualize Ca2+ signaling in developing animal systems. Biochim Biophys Acta Gen Subj 2011; 1820:1160-8. [PMID: 22198462 DOI: 10.1016/j.bbagen.2011.12.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 12/07/2011] [Accepted: 12/08/2011] [Indexed: 12/17/2022]
Abstract
BACKGROUND In recent years, as our understanding of the various roles played by Ca2+ signaling in development and differentiation has expanded, the challenge of imaging Ca2+ dynamics within living cells, tissues, and whole animal systems has been extended to include specific signaling activity in organelles and non-membrane bound sub-cellular domains. SCOPE OF REVIEW In this review we outline how recent advances in genetics and molecular biology have contributed to improving and developing current bioluminescence-based Ca2+ imaging techniques. Reporters can now be targeted to specific cell types, or indeed organelles or domains within a particular cell. MAJOR CONCLUSIONS These advances have contributed to our current understanding of the specificity and heterogeneity of developmental Ca2+ signaling. The improvement in the spatial resolution that results from specifically targeting a Ca2+ reporter has helped to reveal how a ubiquitous signaling messenger like Ca2+ can regulate coincidental but different signaling events within an individual cell; a Ca2+ signaling paradox that until now has been hard to explain. GENERAL SIGNIFICANCE Techniques used to target specific reporters via genetic means will have applications beyond those of the Ca2+ signaling field, and these will, therefore, make a significant contribution in extending our understanding of the signaling networks that regulate animal development. This article is part of a Special Issue entitled Biochemical, biophysical and genetic approaches to intracellular calcium signalling.
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Affiliation(s)
- Sarah E Webb
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong.
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23
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Bakayan A, Vaquero CF, Picazo F, Llopis J. Red fluorescent protein-aequorin fusions as improved bioluminescent Ca2+ reporters in single cells and mice. PLoS One 2011; 6:e19520. [PMID: 21589654 PMCID: PMC3092744 DOI: 10.1371/journal.pone.0019520] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 04/08/2011] [Indexed: 11/18/2022] Open
Abstract
Bioluminescence recording of Ca(2+) signals with the photoprotein aequorin does not require radiative energy input and can be measured with a low background and good temporal resolution. Shifting aequorin emission to longer wavelengths occurs naturally in the jellyfish Aequorea victoria by bioluminescence resonance energy transfer (BRET) to the green fluorescent protein (GFP). This process has been reproduced in the molecular fusions GFP-aequorin and monomeric red fluorescent protein (mRFP)-aequorin, but the latter showed limited transfer efficiency. Fusions with strong red emission would facilitate the simultaneous imaging of Ca(2+) in various cell compartments. In addition, they would also serve to monitor Ca(2+) in living organisms since red light is able to cross animal tissues with less scattering. In this study, aequorin was fused to orange and various red fluorescent proteins to identify the best acceptor in red emission bands. Tandem-dimer Tomato-aequorin (tdTA) showed the highest BRET efficiency (largest energy transfer critical distance R(0)) and percentage of counts in the red band of all the fusions studied. In addition, red fluorophore maturation of tdTA within cells was faster than that of other fusions. Light output was sufficient to image ATP-induced Ca(2+) oscillations in single HeLa cells expressing tdTA. Ca(2+) rises caused by depolarization of mouse neuronal cells in primary culture were also recorded, and changes in fine neuronal projections were spatially resolved. Finally, it was also possible to visualize the Ca(2+) activity of HeLa cells injected subcutaneously into mice, and Ca(2+) signals after depositing recombinant tdTA in muscle or the peritoneal cavity. Here we report that tdTA is the brightest red bioluminescent Ca(2+) sensor reported to date and is, therefore, a promising probe to study Ca(2+) dynamics in whole organisms or tissues expressing the transgene.
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Affiliation(s)
- Adil Bakayan
- Facultad de Medicina and Centro Regional de Investigaciones Biomédicas (CRIB), University of Castilla-La Mancha, Albacete, Spain
| | - Cecilia F. Vaquero
- Facultad de Medicina and Centro Regional de Investigaciones Biomédicas (CRIB), University of Castilla-La Mancha, Albacete, Spain
| | - Fernando Picazo
- Facultad de Medicina and Centro Regional de Investigaciones Biomédicas (CRIB), University of Castilla-La Mancha, Albacete, Spain
| | - Juan Llopis
- Facultad de Medicina and Centro Regional de Investigaciones Biomédicas (CRIB), University of Castilla-La Mancha, Albacete, Spain
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24
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Ca2+-regulated photoproteins: effective immunoassay reporters. SENSORS 2010; 10:11287-300. [PMID: 22163526 PMCID: PMC3231056 DOI: 10.3390/s101211287] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 11/24/2010] [Accepted: 12/03/2010] [Indexed: 11/19/2022]
Abstract
Ca2+-regulated photoproteins of luminous marine coelenterates are of interest and a challenge for researchers as a unique bioluminescent system and as a promising analytical instrument for both in vivo and in vitro applications. The proteins are comprehensively studied as to biochemical properties, tertiary structures, bioluminescence mechanism, etc. This knowledge, along with available recombinant proteins serves the basis for development of unique bioluminescent detection systems that are “self-contained”, triggerable, fast, highly sensitive, and non-hazardous. In the paper, we focus on the use of photoproteins as reporters in binding assays based on immunological recognition element—bioluminescent immunoassay and hybridization immunoassay, their advantages and prospects.
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25
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Naumann EA, Kampff AR, Prober DA, Schier AF, Engert F. Monitoring neural activity with bioluminescence during natural behavior. Nat Neurosci 2010; 13:513-20. [PMID: 20305645 PMCID: PMC2846983 DOI: 10.1038/nn.2518] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 02/22/2010] [Indexed: 02/07/2023]
Abstract
Existing techniques for monitoring neural activity in awake, freely behaving vertebrates are invasive and difficult to target to genetically identified neurons. We used bioluminescence to non-invasively monitor the activity of genetically specified neurons in freely behaving zebrafish. Transgenic fish with the Ca(2+)-sensitive photoprotein green fluorescent protein (GFP)-Aequorin in most neurons generated large and fast bioluminescent signals that were related to neural activity, neuroluminescence, which could be recorded continuously for many days. To test the limits of this technique, we specifically targeted GFP-Aequorin to the hypocretin-positive neurons of the hypothalamus. We found that neuroluminescence generated by this group of approximately 20 neurons was associated with periods of increased locomotor activity and identified two classes of neural activity corresponding to distinct swim latencies. Our neuroluminescence assay can report, with high temporal resolution and sensitivity, the activity of small subsets of neurons during unrestrained behavior.
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Affiliation(s)
- Eva A Naumann
- Department of Molecular and Cellular Biology, Center for Brain Science, Harvard University, Cambridge, Massachusetts, USA
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26
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Webb SE, Rogers KL, Karplus E, Miller AL. The use of aequorins to record and visualize Ca(2+) dynamics: from subcellular microdomains to whole organisms. Methods Cell Biol 2010; 99:263-300. [PMID: 21035690 DOI: 10.1016/b978-0-12-374841-6.00010-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In this chapter, we describe the practical aspects of measuring [Ca(2+)] transients that are generated in a particular cytoplasmic domain, or within a specific organelle or its periorganellar environment, using bioluminescent, genetically encoded and targeted Ca(2+) reporters, especially those based on apoaequorin. We also list examples of the organisms, tissues, and cells that have been transfected with apoaequorin or an apoaequorin-BRET complex, as well as of the organelles and subcellular domains that have been specifically targeted with these bioluminescent Ca(2+) reporters. In addition, we summarize the various techniques used to load the apoaequorin cofactor, coelenterazine, and its analogs into cells, tissues, and intact organisms, and we describe recent advances in the detection and imaging technologies that are currently being used to measure and visualize the luminescence generated by the aequorin-Ca(2+) reaction within these various cytoplasmic domains and subcellular compartments.
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Affiliation(s)
- Sarah E Webb
- Biochemistry and Cell Biology Section and State Key Laboratory of Molecular Neuroscience, Division of Life Science, HKUST, Clear Water Bay, Kowloon, Hong Kong, PR China
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Pozzan T, Rudolf R. Measurements of mitochondrial calcium in vivo. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1317-23. [DOI: 10.1016/j.bbabio.2008.11.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 11/20/2008] [Accepted: 11/21/2008] [Indexed: 12/21/2022]
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Martin JR. In VivoBrain Imaging: Fluorescence or Bioluminescence, Which to Choose? J Neurogenet 2009; 22:285-307. [DOI: 10.1080/01677060802298517] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Gammon ST, Villalobos VM, Roshal M, Samrakandi M, Piwnica-Worms D. Rational design of novel red-shifted BRET pairs: Platforms for real-time single-chain protease biosensors. Biotechnol Prog 2009; 25:559-69. [PMID: 19330851 DOI: 10.1002/btpr.144] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bioluminescence resonance energy transfer (BRET) systems to date have been dominated by use of blue-green Renilla luciferase (Rluc) as the energy donor. Although effective in many cases, the expense and unfavorable biochemical attributes of the substrate (phenylcoelenterazine) limit utility of Rluc-based BRET systems. Herein we report a series of novel BRET pairs based on luciferases that utilize D-luciferin, resulting in red-shifted photonic outputs, favorable biochemical attributes, and increased efficacy. We developed a modified Förster equation to predict optimal BRET luciferase donor-fluorophore pairs and identified tdTomato as the optimal red fluorophore acceptor for click beetle green luciferase (CBG). A prototypical single-chain protease biosensor, capable of reporting on executioner caspase activity in live cells and in real-time, was generated by inserting a DEVD linker between CBG and tdTomato and validated in vitro with recombinant caspases and in cellulo with apoptosis-sensitive and -resistant cell lines. High signal-to-noise ratios ( approximately 33) and Z' factors (0.85) were observed in live cell longitudinal studies, sufficient for high-throughput screening. Thus, we illustrate a general methodology for the rational design of new BRET systems and provide a novel single-chain BRET protease biosensor that is long lived, red-shifted, and utilizes D-luciferin.
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Affiliation(s)
- Seth T Gammon
- Dept. of Molecular Biology and Pharmacology, and Molecular Imaging Center, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Szokol K, Perreault MC. Imaging synaptically mediated responses produced by brainstem inputs onto identified spinal neurons in the neonatal mouse. J Neurosci Methods 2009; 180:1-8. [PMID: 19427523 DOI: 10.1016/j.jneumeth.2009.01.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 01/21/2009] [Accepted: 01/22/2009] [Indexed: 02/07/2023]
Abstract
Descending inputs to spinal cord neurons in mammals have previously been characterized functionally using microelectrode recording of single neurons, a technique with high spatial and temporal resolution but low yield. Consequently our knowledge about the functional connections between the brain and the spinal cord has been accumulating at a very low pace. Here we describe a high throughput optical recording approach in an ex vivo brainstem-spinal cord preparation of the neonatal mouse that permits screening many spinal neurons simultaneously for synaptic inputs from descending axons. The fluorescent calcium indicator calcium green dextran amine was loaded retrogradely into specific spinal neuron populations, including motoneurons (MNs) of the medial and lateral motor columns and two populations of interneurons with descending axons (dINs) in the ventral funiculus. Focal electrical stimulation of brainstem neuron populations with descending axons generated synaptic responses revealed by transient increases in intracellular calcium concentration in all four populations of spinal neurons. The resultant fluorescence signals could be readily visualized in individual MNs directly through the ventral white matter. In the more deeply located dINs, responses could be readily visualized in individual neurons from the surface of an oblique cut through the spinal cord. The rapid optical investigation of functional connections between brainstem descending neurons and various populations of spinal neurons in the living mammalian preparation should help uncover some of the key features of supraspinal sensory and motor control and provide a valuable tool for examining the re-innervation of spinal neurons by descending axons after spinal cord regeneration.
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Affiliation(s)
- Karolina Szokol
- University of Oslo, Institute of Basic Medical Sciences (Domus Medica), Department of Physiology, N-0317 Oslo, Norway
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Alonso MT, Manjarrés IM, García-Sancho J. Modulation of calcium signalling by intracellular organelles seen with targeted aequorins. Acta Physiol (Oxf) 2009; 195:37-49. [PMID: 18983457 DOI: 10.1111/j.1748-1716.2008.01920.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cytosolic Ca(2+) signals that trigger cell responses occur either as localized domains of high Ca(2+) concentration or as propagating Ca(2+) waves. Cytoplasmic organelles, taking up or releasing Ca(2+) to the cytosol, shape the cytosolic signals. On the other hand, Ca(2+) concentration inside organelles is also important in physiology and pathophysiology. Comprehensive study of these matters requires to measure [Ca(2+)] inside organelles and at the relevant cytosolic domains. Aequorins, the best-known chemiluminescent Ca(2+) probes, are excellent for this end as they do not require stressing illumination, have a large dynamic range and a sharp Ca(2+)-dependence, can be targeted to the appropriate location and engineered to have the proper Ca(2+) affinity. Using this methodology, we have evidenced the existence in chromaffin cells of functional units composed by three closely interrelated elements: (1) plasma membrane Ca(2+) channels, (2) subplasmalemmal endoplasmic reticulum and (3) mitochondria. These Ca(2+)-signalling triads optimize Ca(2+) microdomains for secretion and prevent propagation of the Ca(2+) wave towards the cell core. Oscillatory cytosolic Ca(2+) signals originate also oscillations of mitochondrial Ca(2+) in several cell types. The nuclear envelope slows down the propagation of the Ca(2+) wave to the nucleus and filters high frequencies. On the other hand, inositol-trisphosphate may produce direct release of Ca(2+) to the nucleoplasm in GH(3) pituitary cells, thus providing mechanisms for selective nuclear signalling. Aequorins emitting at different wavelengths, prepared by fusion either with green or red fluorescent protein, permit simultaneous and independent monitorization of the Ca(2+) signals in different subcellular domains within the same cell.
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Affiliation(s)
- M T Alonso
- Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, Valladolid, Spain
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Rogers KL, Martin JR, Renaud O, Karplus E, Nicola MA, Nguyen M, Picaud S, Shorte SL, Brûlet P. Electron-multiplying charge-coupled detector-based bioluminescence recording of single-cell Ca2+. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:031211. [PMID: 18601535 DOI: 10.1117/1.2937236] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The construction and application of genetically encoded intracellular calcium concentration ([Ca2+]i) indicators has a checkered history. Excitement raised over the creation of new probes is often followed by disappointment when it is found that the initial demonstrations of [Ca2+]i sensing capability cannot be leveraged into real scientific advances. Recombinant apo-aequorin cloned from Aequorea victoria was the first Ca2+ sensitive protein genetically targeted to subcellular compartments. In the jellyfish, bioluminescence resonance energy transfer (BRET) between Ca2+ bound aequorin and green fluorescent protein (GFP) emits green light. Similarly, Ca2+ sensitive bioluminescent reporters undergoing BRET have been constructed between aequorin and GFP, and more recently with other fluorescent protein variants. These hybrid proteins display red-shifted spectrums and have higher light intensities and stability compared to aequorin alone. We report BRET measurement of single-cell [Ca2+]i based on the use of electron-multiplying charge-coupled-detector (EMCCD) imaging camera technology, mounted on either a bioluminescence or conventional microscope. Our results show for the first time how these new technologies make facile long-term monitoring of [Ca2+]i at the single-cell level, obviating the need for expensive, fragile, and sophisticated equipment based on image-photon-detectors (IPD) that were until now the only technical recourse to dynamic BRET experiments of this type.
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Affiliation(s)
- Kelly L Rogers
- Plate-forme d'Imagerie Dynamique, Imagopole,Institut Pasteur, Paris, France.
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Manjarrés IM, Chamero P, Domingo B, Molina F, Llopis J, Alonso MT, García-Sancho J. Red and green aequorins for simultaneous monitoring of Ca2+ signals from two different organelles. Pflugers Arch 2008; 455:961-70. [PMID: 17912545 DOI: 10.1007/s00424-007-0349-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 09/08/2007] [Accepted: 09/10/2007] [Indexed: 10/22/2022]
Abstract
Simultaneous control of different functions by calcium signals is possible because of subcellular compartmentalization. Targeted chemiluminescent Ca2+ probes, such as aequorins (AEQs) are optimal for detecting signals originating in different subcellular domains, but imaging is difficult because of low photon yield causing poor spatiotemporal resolution. To overcome this problem, we have co-expressed two spectrally distinct AEQs in different subcellular locations within the same cells. Seven chimeric proteins containing either green- or red-emitting AEQs, with different targeting sequences and Ca2+ affinities, have been designed and tested. We show here evidence for physical and functional independence of the different probes. Cytosolic Ca2+ signals were mirrored in the nucleus, but amplified inside mitochondria and endoplasmic reticulum, and had different time courses in the various locations. Our results demonstrate that these novel tools permit simultaneous and independent monitoring of [Ca2+] in different subcellular domains of the same cell.
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Affiliation(s)
- Isabel M Manjarrés
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas, c/Sanz y Forés s/n, 47003 Valladolid, Spain
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