1
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Mancini AE, Rizzo MA. A Novel Single-Color FRET Sensor for Rho-Kinase Reveals Calcium-Dependent Activation of RhoA and ROCK. SENSORS (BASEL, SWITZERLAND) 2024; 24:6869. [PMID: 39517770 PMCID: PMC11548655 DOI: 10.3390/s24216869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2024] [Revised: 10/17/2024] [Accepted: 10/21/2024] [Indexed: 11/16/2024]
Abstract
Ras homolog family member A (RhoA) acts as a signaling hub in many cellular processes, including cytoskeletal dynamics, division, migration, and adhesion. RhoA activity is tightly spatiotemporally controlled, but whether downstream effectors share these activation dynamics is unknown. We developed a novel single-color FRET biosensor to measure Rho-associated kinase (ROCK) activity with high spatiotemporal resolution in live cells. We report the validation of the Rho-Kinase Activity Reporter (RhoKAR) biosensor. RhoKAR activation was specific to ROCK activity and was insensitive to PKA activity. We then assessed the mechanisms of ROCK activation in mouse fibroblasts. Increasing intracellular calcium with ionomycin increased RhoKAR activity and depleting intracellular calcium with EGTA decreased RhoKAR activity. We also investigated the signaling intermediates in this process. Blocking calmodulin or CaMKII prevented calcium-dependent activation of ROCK. These results indicate that ROCK activity is increased by calcium in fibroblasts and that this activation occurs downstream of CaM/CaMKII.
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Affiliation(s)
| | - Megan A. Rizzo
- Department of Pharmacology, Physiology, and Drug Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
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2
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Jiang Q, Shao S, Li N, Zhang Z, Liu B. Non-Invasive On-Off Fluorescent Biosensor for Endothelial Cell Detection. BIOSENSORS 2024; 14:489. [PMID: 39451702 PMCID: PMC11506521 DOI: 10.3390/bios14100489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2024] [Revised: 09/30/2024] [Accepted: 10/08/2024] [Indexed: 10/26/2024]
Abstract
For rapid and convenient detection of living endothelial cells (ECs) specifically without immunostaining, we developed a biosensor based on turn-on fluorescent protein, named LV-EcpG. It includes a high-affinity peptide E12P obtained through phage display technology for specifically recognizing ECs and a turn-on EGFP fused with two linker peptides. The "on-off" switching mechanism of this genetically encoded fluorescent protein-based biosensor (FPB) ensured that fluorescence signals were activated only when binding with ECs, thus enabling these FPB characters for direct, visual, and non-invasive detection of ECs. Its specificity and multicolor imaging capability established LV-EcpG as a powerful tool for live EC research, with significant potential for diagnosing and treating cardiovascular diseases and tumor angiogenesis.
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Affiliation(s)
- Qingyun Jiang
- Cancer Hospital of Dalian University of Technology, Shenyang 110042, China; (Q.J.)
- Faculty of Medicine, Liaoning Key Lab of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Shuai Shao
- Cancer Hospital of Dalian University of Technology, Shenyang 110042, China; (Q.J.)
- Faculty of Medicine, Liaoning Key Lab of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Na Li
- Cancer Hospital of Dalian University of Technology, Shenyang 110042, China; (Q.J.)
- Faculty of Medicine, Liaoning Key Lab of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Zhengyao Zhang
- School of Chemical Engineering, Ocean and Life Sciences, Dalian University of Technology, Panjin 124221, China
| | - Bo Liu
- Cancer Hospital of Dalian University of Technology, Shenyang 110042, China; (Q.J.)
- Faculty of Medicine, Liaoning Key Lab of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
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3
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Hagimori M, Hara F, Mizuyama N, Takada S, Hayashi S, Haraguchi T, Hatanaka Y, Nagao T, Tanaka S, Yoshii M, Yoshida M. Synthesis and Photophysical Characterization of Fluorescent Naphtho[2,3- d]thiazole-4,9-Diones and Their Antimicrobial Activity against Staphylococcus Strains. Molecules 2024; 29:2777. [PMID: 38930841 PMCID: PMC11206905 DOI: 10.3390/molecules29122777] [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: 04/24/2024] [Revised: 06/07/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
The chemical reaction of 2-(methylsulfinyl)naphtho[2,3-d]thiazole-4,9-dione (3) using different amines, including benzylamine (4a), morpholine (4b), thiomorpholine (4c), piperidine (4d), and 4-methylpiperazine (4e), produced corresponding new tricyclic naphtho[2,3-d]thiazole-4,9-dione compounds (5a-e) in moderate-to-good yields. The photophysical properties and antimicrobial activities of these compounds (5a-e) were then characterized. Owing to the extended π-conjugated system of naphtho[2,3-d]thiazole-4,9-dione skeleton and substituent effect, 5a-e showed fluorescence both in solution and in the solid state. The introduction of nitrogen-containing heterocycles at position 2 of the thiazole ring on naphtho[2,3-d]thiazole-4,9-dione led to large bathochromic shifts in solution, and 5b-e exhibited orange-red fluorescence with emission maxima of over 600 nm in highly polar solvents. Staphylococcus aureus (S. aureus) is a highly pathogenic bacterium, and infection with its antimicrobial-resistant pathogen methicillin-resistant S. aureus (MRSA) results in serious clinical problems. In this study, we also investigated the antimicrobial activities of 5a-e against S. aureus, MRSA, and S. epidermidis. Compounds 5c with thiomorpholine group and 5e with 4-methylpiperazine group showed potent antimicrobial activity against these bacteria. These results will lead to the development of new fluorescent dyes with antimicrobial activity in the future.
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Affiliation(s)
- Masayori Hagimori
- Department of Analitical Chemistry, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (F.H.); (S.T.)
| | - Fumiko Hara
- Department of Analitical Chemistry, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (F.H.); (S.T.)
| | - Naoko Mizuyama
- Division of Medical Innovation, Translational Research Center for Medical Innovation, 1-5-4 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Hyogo, Japan;
| | - Shinya Takada
- Department of Analitical Chemistry, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (F.H.); (S.T.)
| | - Saki Hayashi
- Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (S.H.); (T.H.)
| | - Tamami Haraguchi
- Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (S.H.); (T.H.)
- Institute for Women’s Career Advancement and Gender Equality Development, Mukogawa Women’s University, 6-46 Ikebiraki, Nishinomiya City 663-8558, Hyogo, Japan
| | - Yoshiro Hatanaka
- Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka City 536-8553, Osaka, Japan; (Y.H.); (T.N.); (S.T.); (M.Y.)
| | - Toshihiro Nagao
- Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka City 536-8553, Osaka, Japan; (Y.H.); (T.N.); (S.T.); (M.Y.)
| | - Shigemitsu Tanaka
- Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka City 536-8553, Osaka, Japan; (Y.H.); (T.N.); (S.T.); (M.Y.)
| | - Miki Yoshii
- Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka City 536-8553, Osaka, Japan; (Y.H.); (T.N.); (S.T.); (M.Y.)
| | - Miyako Yoshida
- Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya City 663-8179, Hyogo, Japan; (S.H.); (T.H.)
- Institute for Women’s Career Advancement and Gender Equality Development, Mukogawa Women’s University, 6-46 Ikebiraki, Nishinomiya City 663-8558, Hyogo, Japan
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4
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Stengl M, Schneider AC. Contribution of membrane-associated oscillators to biological timing at different timescales. Front Physiol 2024; 14:1243455. [PMID: 38264332 PMCID: PMC10803594 DOI: 10.3389/fphys.2023.1243455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 12/12/2023] [Indexed: 01/25/2024] Open
Abstract
Environmental rhythms such as the daily light-dark cycle selected for endogenous clocks. These clocks predict regular environmental changes and provide the basis for well-timed adaptive homeostasis in physiology and behavior of organisms. Endogenous clocks are oscillators that are based on positive feedforward and negative feedback loops. They generate stable rhythms even under constant conditions. Since even weak interactions between oscillators allow for autonomous synchronization, coupling/synchronization of oscillators provides the basis of self-organized physiological timing. Amongst the most thoroughly researched clocks are the endogenous circadian clock neurons in mammals and insects. They comprise nuclear clockworks of transcriptional/translational feedback loops (TTFL) that generate ∼24 h rhythms in clock gene expression entrained to the environmental day-night cycle. It is generally assumed that this TTFL clockwork drives all circadian oscillations within and between clock cells, being the basis of any circadian rhythm in physiology and behavior of organisms. Instead of the current gene-based hierarchical clock model we provide here a systems view of timing. We suggest that a coupled system of autonomous TTFL and posttranslational feedback loop (PTFL) oscillators/clocks that run at multiple timescales governs adaptive, dynamic homeostasis of physiology and behavior. We focus on mammalian and insect neurons as endogenous oscillators at multiple timescales. We suggest that neuronal plasma membrane-associated signalosomes constitute specific autonomous PTFL clocks that generate localized but interlinked oscillations of membrane potential and intracellular messengers with specific endogenous frequencies. In each clock neuron multiscale interactions of TTFL and PTFL oscillators/clocks form a temporally structured oscillatory network with a common complex frequency-band comprising superimposed multiscale oscillations. Coupling between oscillator/clock neurons provides the next level of complexity of an oscillatory network. This systemic dynamic network of molecular and cellular oscillators/clocks is suggested to form the basis of any physiological homeostasis that cycles through dynamic homeostatic setpoints with a characteristic frequency-band as hallmark. We propose that mechanisms of homeostatic plasticity maintain the stability of these dynamic setpoints, whereas Hebbian plasticity enables switching between setpoints via coupling factors, like biogenic amines and/or neuropeptides. They reprogram the network to a new common frequency, a new dynamic setpoint. Our novel hypothesis is up for experimental challenge.
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Affiliation(s)
- Monika Stengl
- Department of Biology, Animal Physiology/Neuroethology, University of Kassel, Kassel, Germany
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5
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Posner C, Mehta S, Zhang J. Fluorescent biosensor imaging meets deterministic mathematical modelling: quantitative investigation of signalling compartmentalization. J Physiol 2023; 601:4227-4241. [PMID: 37747358 PMCID: PMC10764149 DOI: 10.1113/jp282696] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 09/06/2023] [Indexed: 09/26/2023] Open
Abstract
Cells execute specific responses to diverse environmental cues by encoding information in distinctly compartmentalized biochemical signalling reactions. Genetically encoded fluorescent biosensors enable the spatial and temporal monitoring of signalling events in live cells. Temporal and spatiotemporal computational models can be used to interpret biosensor experiments in complex biochemical networks and to explore hypotheses that are difficult to test experimentally. In this review, we first provide brief discussions of the experimental toolkit of fluorescent biosensors as well as computational basics with a focus on temporal and spatiotemporal deterministic models. We then describe how we used this combined approach to identify and investigate a protein kinase A (PKA) - cAMP - Ca2+ oscillatory circuit in MIN6 β cells, a mouse pancreatic β cell system. We describe the application of this combined approach to interrogate how this oscillatory circuit is differentially regulated in a nano-compartment formed at the plasma membrane by the scaffolding protein A kinase anchoring protein 79/150. We leveraged both temporal and spatiotemporal deterministic models to identify the key regulators of this oscillatory circuit, which we confirmed with further experiments. The powerful approach of combining live-cell biosensor imaging with quantitative modelling, as discussed here, should find widespread use in the investigation of spatiotemporal regulation of cell signalling.
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Affiliation(s)
- Clara Posner
- Department of Pharmacology, University of California, San Diego, CA, USA
- Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, CA, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, CA, USA
- Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, CA, USA
- Department of Chemistry and Biochemistry, University of California, San Diego, CA, USA
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6
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Baron L, Hadjerci J, Thoidingjam L, Plays M, Bucci R, Morris N, Müller S, Sindikubwabo F, Solier S, Cañeque T, Colombeau L, Blouin CM, Lamaze C, Puisieux A, Bono Y, Gaillet C, Laraia L, Vauzeilles B, Taran F, Papot S, Karoyan P, Duval R, Mahuteau-Betzer F, Arimondo P, Cariou K, Guichard G, Micouin L, Ethève-Quelquejeu M, Verga D, Versini A, Gasser G, Tang C, Belmont P, Linkermann A, Bonfio C, Gillingham D, Poulsen T, Di Antonio M, Lopez M, Guianvarc'h D, Thomas C, Masson G, Gautier A, Johannes L, Rodriguez R. PSL Chemical Biology Symposia Third Edition: A Branch of Science in its Explosive Phase. Chembiochem 2023; 24:e202300093. [PMID: 36942862 DOI: 10.1002/cbic.202300093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Indexed: 03/23/2023]
Abstract
This symposium is the third PSL (Paris Sciences & Lettres) Chemical Biology meeting (2016, 2019, 2023) held at Institut Curie. This initiative originally started at Institut de Chimie des Substances Naturelles (ICSN) in Gif-sur-Yvette (2013, 2014), under the directorship of Professor Max Malacria, with a strong focus on chemistry. It was then continued at the Institut Curie (2015) covering a larger scope, before becoming the official PSL Chemical Biology meeting. This latest edition was postponed twice for the reasons that we know. This has given us the opportunity to invite additional speakers of great standing. This year, Institut Curie hosted around 300 participants, including 220 on site and over 80 online. The pandemic has had, at least, the virtue of promoting online meetings, which we came to realize is not perfect but has its own merits. In particular, it enables those with restricted time and resources to take part in events and meetings, which can now accommodate unlimited participants. We apologize to all those who could not attend in person this time due to space limitation at Institut Curie.
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Affiliation(s)
- Leeroy Baron
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Justine Hadjerci
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Leishemba Thoidingjam
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Marina Plays
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Romain Bucci
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Nolwenn Morris
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Sebastian Müller
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Fabien Sindikubwabo
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Stéphanie Solier
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Tatiana Cañeque
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Ludovic Colombeau
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Cedric M Blouin
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Christophe Lamaze
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Alain Puisieux
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Yannick Bono
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Christine Gaillet
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Luca Laraia
- Technical University of Denmark, Department of Chemistry, 2800, Kgs. Lyngby, Denmark
| | - Boris Vauzeilles
- Université Paris-Saclay, CNRS UPR 2301, 91198, Gif-sur-Yvette, France
| | - Frédéric Taran
- Université Paris-Saclay, CEA, 91191, Gif-sur-Yvette, France
| | - Sébastien Papot
- Université de Poitiers, CNRS UMR 7285, 86073, Poitiers, France
| | - Philippe Karoyan
- PSL Université Paris, Sorbonne Université Ecole Normale Supérieure, CNRS UMR 7203, 75005, Paris, France
| | - Romain Duval
- Faculté de Pharmacie de Paris, Université Paris Cité CNRS UMR 261, 75006, Paris, France
| | | | | | - Kevin Cariou
- PSL Université Paris, Chimie ParisTech, CNRS, Institute of Chemistry and Health Sciences CNRS UMR 8060, 75005, Paris, France
| | - Gilles Guichard
- Université de Bordeaux, CNRS, Bordeaux INP CBMN, UMR 5248, 33600, Pessac, France
| | | | | | - Daniela Verga
- PSL Université Paris, Institut Curie CNRS UMR 9187, INSERM U1196, 91405, Orsay, France
| | - Antoine Versini
- University of Zurich, Department of Chemistry, 8057, Zurich, Switzerland
| | - Gilles Gasser
- PSL Université Paris, Chimie ParisTech, CNRS, Institute of Chemistry and Health Sciences CNRS UMR 8060, 75005, Paris, France
| | - Cong Tang
- Universidade de Lisboa, Instituto de Medicina Molecular João Lobo Antunes, 1649-028, Lisboa, Portugal
| | | | - Andreas Linkermann
- Technische Universität Dresden Department of Internal Medicine 3, 01062, Dresden, Germany
| | - Claudia Bonfio
- Université de Strasbourg, CNRS UMR 7006, 67000, Strasbourg, France
| | | | - Thomas Poulsen
- Aarhus University, Department of Chemistry, 8000, Aarhus C Aarhus, Denmark
| | - Marco Di Antonio
- Imperial College London, Molecular Sciences Research Hub, London, W12 0BZ, UK
| | - Marie Lopez
- Université de Montpellier, CNRS UMR 5247, 34000, Montpellier, France
| | | | - Christophe Thomas
- PSL Université Paris, Chimie ParisTech CNRS UMR 6226, 75005, Paris, France
| | - Géraldine Masson
- Université Paris-Saclay, CNRS UPR 2301, 91198, Gif-sur-Yvette, France
| | - Arnaud Gautier
- Sorbonne Université, École Normale Supérieure, Université PSL, CNRS, Laboratoire des Biomolécules, LBM, 75005, Paris, France
| | - Ludger Johannes
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
| | - Raphaël Rodriguez
- Institut Curie, Department of Cellular and Chemical Biology, UMR 3666 CNRS, U1143 INSERM, PSL Université Paris, 75005, Paris, France
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7
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Greenwald E, Posner C, Bharath A, Lyons A, Salmerón C, Sriram K, Wiley SZ, Insel PA, Zhang J. GPCR Signaling Measurement and Drug Profiling with an Automated Live-Cell Microscopy System. ACS Sens 2023; 8:19-27. [PMID: 36602887 PMCID: PMC9994309 DOI: 10.1021/acssensors.2c01341] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A major limitation of time-lapse microscopy combined with fluorescent biosensors, a powerful tool for quantifying spatiotemporal dynamics of signaling in single living cells, is low-experimental throughput. To overcome this limitation, we created a highly customizable, MATLAB-based platform: flexible automated liquid-handling combined microscope (FALCOscope) that coordinates an OpenTrons liquid handler and a fluorescence microscope to automate drug treatments, fluorescence imaging, and single-cell analysis. To test the feasibility of the FALCOscope, we quantified G protein-coupled receptor (GPCR)-stimulated Protein Kinase A activity and cAMP responses to GPCR agonists and antagonists. We also characterized cAMP dynamics induced by GPR68/OGR1, a proton-sensing GPCR, in response to variable extracellular pH values. GPR68-induced cAMP responses were more transient in acidic than neutral pH values, suggesting a pH-dependence for signal attenuation. Ogerin, a GPR68 positive allosteric modulator, enhanced cAMP response most strongly at pH 7.0 and sustained cAMP response for acidic pH values, thereby demonstrating the capability of the FALCOscope to capture allosteric modulation. At a high concentration, ogerin increased cAMP signaling independent of GPR68, likely via phosphodiesterase inhibition. The FALCOscope system thus enables enhanced throughput single-cell dynamic measurements and is a versatile system for interrogating spatiotemporal regulation of signaling molecules in living cells and for drug profiling and screening.
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Affiliation(s)
- Eric Greenwald
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Clara Posner
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Ananya Bharath
- Department of Chemical Engineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Anne Lyons
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Cristina Salmerón
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Krishna Sriram
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Shu Z Wiley
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Paul A Insel
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States.,Department of Medicine, University of California, San Diego, La Jolla, California 92093 United States
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States.,Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States.,Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
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8
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Stellon D, Talbot J, Hewitt AW, King AE, Cook AL. Seeing Neurodegeneration in a New Light Using Genetically Encoded Fluorescent Biosensors and iPSCs. Int J Mol Sci 2023; 24:1766. [PMID: 36675282 PMCID: PMC9861453 DOI: 10.3390/ijms24021766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Neurodegenerative diseases present a progressive loss of neuronal structure and function, leading to cell death and irrecoverable brain atrophy. Most have disease-modifying therapies, in part because the mechanisms of neurodegeneration are yet to be defined, preventing the development of targeted therapies. To overcome this, there is a need for tools that enable a quantitative assessment of how cellular mechanisms and diverse environmental conditions contribute to disease. One such tool is genetically encodable fluorescent biosensors (GEFBs), engineered constructs encoding proteins with novel functions capable of sensing spatiotemporal changes in specific pathways, enzyme functions, or metabolite levels. GEFB technology therefore presents a plethora of unique sensing capabilities that, when coupled with induced pluripotent stem cells (iPSCs), present a powerful tool for exploring disease mechanisms and identifying novel therapeutics. In this review, we discuss different GEFBs relevant to neurodegenerative disease and how they can be used with iPSCs to illuminate unresolved questions about causes and risks for neurodegenerative disease.
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Affiliation(s)
- David Stellon
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, TAS 7000, Australia
| | - Jana Talbot
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, TAS 7000, Australia
| | - Alex W. Hewitt
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
| | - Anna E. King
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, TAS 7000, Australia
| | - Anthony L. Cook
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, TAS 7000, Australia
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9
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Schmitt DL, Mehta S, Zhang J. Study of spatiotemporal regulation of kinase signaling using genetically encodable molecular tools. Curr Opin Chem Biol 2022; 71:102224. [PMID: 36347198 PMCID: PMC10031819 DOI: 10.1016/j.cbpa.2022.102224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 09/20/2022] [Accepted: 09/23/2022] [Indexed: 01/27/2023]
Abstract
Precise spatiotemporal organization and regulation of signal transduction networks are essential for cellular response to internal and external cues. To understand how this biochemical activity architecture impacts cellular function, many genetically encodable tools which regulate kinase activity at a subcellular level have been developed. In this review, we highlight various types of genetically encodable molecular tools, including tools to regulate endogenous kinase activity and biorthogonal techniques to perturb kinase activity. Finally, we emphasize the use of these tools alongside biosensors for kinase activity to measure and perturb kinase activity in real time for a better understanding of the cellular biochemical activity architecture.
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Affiliation(s)
- Danielle L Schmitt
- Department of Pharmacology, University of California San Diego, USA; Department of Chemistry and Biochemistry, University of California Los Angeles, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California San Diego, USA
| | - Jin Zhang
- Department of Pharmacology, University of California San Diego, USA; Department of Bioengineering, University of California San Diego, USA; Department of Chemistry and Biochemistry, University of California San Diego, USA.
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10
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Spatial regulation of AMPK signaling revealed by a sensitive kinase activity reporter. Nat Commun 2022; 13:3856. [PMID: 35790710 PMCID: PMC9256702 DOI: 10.1038/s41467-022-31190-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 06/06/2022] [Indexed: 12/13/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is a master regulator of cellular energetics which coordinates metabolism by phosphorylating a plethora of substrates throughout the cell. But how AMPK activity is regulated at different subcellular locations for precise spatiotemporal control over metabolism is unclear. Here we present a sensitive, single-fluorophore AMPK activity reporter (ExRai AMPKAR), which reveals distinct kinetic profiles of AMPK activity at the mitochondria, lysosome, and cytoplasm. Genetic deletion of the canonical upstream kinase liver kinase B1 (LKB1) results in slower AMPK activity at lysosomes but does not affect the response amplitude at lysosomes or mitochondria, in sharp contrast to the necessity of LKB1 for maximal cytoplasmic AMPK activity. We further identify a mechanism for AMPK activity in the nucleus, which results from cytoplasmic to nuclear shuttling of AMPK. Thus, ExRai AMPKAR enables illumination of the complex subcellular regulation of AMPK signaling.
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11
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Zhou X, Mehta S, Zhang J. AktAR and Akt-STOPS: Genetically Encodable Molecular Tools to Visualize and Perturb Akt Kinase Activity at Different Subcellular Locations in Living Cells. Curr Protoc 2022; 2:e416. [PMID: 35532280 PMCID: PMC9093046 DOI: 10.1002/cpz1.416] [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: 11/07/2022]
Abstract
The serine/threonine protein kinase Akt integrates diverse upstream inputs to regulate cell survival, growth, metabolism, migration, and differentiation. Mounting evidence suggests that Akt activity is differentially regulated depending on its subcellular location, which can include the plasma membrane, endomembrane, and nuclear compartment. This spatial control of Akt activity is critical for achieving signaling specificity and proper physiological functions, and deregulation of compartment-specific Akt signaling is implicated in various diseases, including cancer and diabetes. Understanding the spatial coordination of the signaling network centered around this key kinase and the underlying regulatory mechanisms requires precise tracking of Akt activity at distinct subcellular compartments within its native biological contexts. To address this challenge, new molecular tools are being developed, enabling us to directly interrogate the spatiotemporal regulation of Akt in living cells. These include, for instance, the newly developed genetically encodable fluorescent-protein-based Akt kinase activity reporter (AktAR2), which serves as a substrate surrogate of Akt kinase and translates Akt-specific phosphorylation into a quantifiable change in Förster resonance energy transfer (FRET). In addition, we developed the Akt substrate tandem occupancy peptide sponge (Akt-STOPS), which allows biochemical perturbation of subcellular Akt activity. Both molecular tools can be readily targeted to distinct subcellular localizations. Here, we describe a workflow to study Akt kinase activity at different subcellular locations in living cells. We provide a protocol for using genetically targeted AktAR2 and Akt-STOPS, along with fluorescence imaging in living NIH3T3 cells, to visualize and perturb, respectively, the activity of endogenous Akt kinase at different subcellular compartments. We further describe a protocol for using chemically inducible dimerization (CID) to control the plasma membrane-specific inhibition of Akt activity in real time. Lastly, we describe a protocol for maintaining NIH3T3 cells in culture, a cell line known to exhibit robust Akt activity. In all, this approach enables interrogation of spatiotemporal regulation and functions of Akt, as well as the intricate signaling networks in which it is embedded, at specific subcellular locations. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Visualizing and perturbing subcellular Akt kinase activity using AktAR and Akt-STOPS Basic Protocol 2: Using chemically inducible dimerization (CID) to control inhibition of Akt at the plasma membrane Support Protocol: Maintaining NIH3T3 cells in culture.
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Affiliation(s)
- Xin Zhou
- Department of Pharmacology, University of California, San Diego, La Jolla, California
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, California
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, California.,Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California.,Department of Bioengineering, University of California, San Diego, La Jolla, California
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12
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Mehta S, Zhang J. Liquid-liquid phase separation drives cellular function and dysfunction in cancer. Nat Rev Cancer 2022; 22:239-252. [PMID: 35149762 PMCID: PMC10036213 DOI: 10.1038/s41568-022-00444-7] [Citation(s) in RCA: 209] [Impact Index Per Article: 69.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/12/2022] [Indexed: 12/11/2022]
Abstract
Cancer is a disease of uncontrollably reproducing cells. It is governed by biochemical pathways that have escaped the regulatory bounds of normal homeostatic balance. This balance is maintained through precise spatiotemporal regulation of these pathways. The formation of biomolecular condensates via liquid-liquid phase separation (LLPS) has recently emerged as a widespread mechanism underlying the spatiotemporal coordination of biological activities in cells. Biomolecular condensates are widely observed to directly regulate key cellular processes involved in cancer cell pathology, and the dysregulation of LLPS is increasingly implicated as a previously hidden driver of oncogenic activity. In this Perspective, we discuss how LLPS shapes the biochemical landscape of cancer cells.
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Affiliation(s)
- 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.
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA.
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
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13
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Li G, Li H, Zhai J, Guo J, Li Q, Wang CF, Chen S. Microfluidic fluorescent platform for rapid and visual detection of veterinary drugs. RSC Adv 2022; 12:8485-8491. [PMID: 35424796 PMCID: PMC8984828 DOI: 10.1039/d2ra00626j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 03/11/2022] [Indexed: 11/21/2022] Open
Abstract
The overuse of veterinary drugs and veterinary drug residues is increasingly becoming an obstacle to sustainable development worldwide. It is therefore imperative to establish a quantitative, sensitive and efficient method for the detection of veterinary drugs. Herein, we developed a visual microfluidic detection platform for rapid and sensitive detection of veterinary drugs using CdTe quantum dots (QDs) with three different ligands as the sensing units. Green-emissive 3-mercaptopropionic acid (MPA)-CdTe QDs, yellow-emissive thioglycolic acid (TGA)-CdTe QDs and orange-emissive N-acetyl-l-cysteine (NAC)-CdTe QDs were synthesized by a sulfhydryl aqueous phase method. These CdTe QDs show selective rapid fluorescence response to pefloxacin (PEF), malachite green (MG), and 1-aminohydantoin hydrochloride (AHD). With the concentration of veterinary drugs increasing, the CdTe QDs reveals a fluorescence color variation from bright to dark until quenched and the response degree of CdTe QDs with different ligands to veterinary drugs is different. Specifically, the limits of detection (LODs) of MPA-CdTe, TGA-CdTe and NAC-CdTe QDs probes for PEF were 7.57 μM, 1.75 μM and 2.90 μM, respectively, and the response was complete in a few seconds, realizing the sensitive and rapid detection of PEF. The three kinds of CdTe QDs could also be used in the detection of other veterinary drugs such as MG and AHD. Finally, a microfluidic detection platform was constructed for visual sensing and rapid detection towards veterinary drugs. The sensor platform holds the advantages of simple operation, low cost, rapid sensing and good sensitivity, and is potentially useful for visual quantitative detection of veterinary drug residues in aquatic products and the environment.
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Affiliation(s)
- Ge Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Hao Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Jiang Zhai
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Jiazhuang Guo
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Qing Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Cai-Feng Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
| | - Su Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials, Nanjing Tech University Nanjing 210009 China +86-25-83172258
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14
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Zhong Y, Zhou X, Guan KL, Zhang J. Rheb regulates nuclear mTORC1 activity independent of farnesylation. Cell Chem Biol 2022; 29:1037-1045.e4. [PMID: 35294906 DOI: 10.1016/j.chembiol.2022.02.006] [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: 06/28/2021] [Revised: 10/26/2021] [Accepted: 02/10/2022] [Indexed: 11/26/2022]
Abstract
The small GTPase Ras homolog enriched in brain (Rheb) plays a critical role in activating the mechanistic target of rapamycin complex 1 (mTORC1), a signaling hub that regulates various cellular functions. We recently observed nuclear mTORC1 activity, raising an intriguing question as to how Rheb, which is known to be farnesylated and localized to intracellular membranes, regulates nuclear mTORC1. In this study, we found that active Rheb is present in the nucleus and required for nuclear mTORC1 activity. We showed that inhibition of farnesyltransferase reduced cytosolic, but not nuclear, mTORC1 activity. Furthermore, a farnesylation-deficient Rheb mutant, with preferential nuclear localization and specific lysosome tethering, enables nuclear and cytosolic mTORC1 activities, respectively. These data suggest that non-farnesylated Rheb is capable of interacting with and activating mTORC1, providing mechanistic insights into the molecular functioning of Rheb as well as regulation of the recently observed, active pool of nuclear mTORC1.
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Affiliation(s)
- Yanghao Zhong
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
| | - Xin Zhou
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Kun-Liang Guan
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
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15
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Chen M, Sun T, Zhong Y, Zhou X, Zhang J. A Highly Sensitive Fluorescent Akt Biosensor Reveals Lysosome-Selective Regulation of Lipid Second Messengers and Kinase Activity. ACS CENTRAL SCIENCE 2021; 7:2009-2020. [PMID: 34963894 PMCID: PMC8704034 DOI: 10.1021/acscentsci.1c00919] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Indexed: 06/14/2023]
Abstract
The serine/threonine protein kinase Akt regulates a wide range of cellular functions via phosphorylation of various substrates distributed throughout the cell, including at the plasma membrane and endomembrane compartments. Disruption of compartmentalized Akt signaling underlies the pathology of many diseases such as cancer and diabetes. However, the specific spatial organization of Akt activity and the underlying regulatory mechanisms, particularly the mechanism controlling its activity at the lysosome, are not clearly understood. We developed a highly sensitive excitation-ratiometric Akt activity reporter (ExRai-AktAR2), enabling the capture of minute changes in Akt activity dynamics at subcellular compartments. In conjunction with super-resolution expansion microscopy, we found that growth factor stimulation leads to increased colocalization of Akt with lysosomes and accumulation of lysosomal Akt activity. We further showed that 3-phosphoinositides (3-PIs) accumulate on the lysosomal surface, in a manner dependent on dynamin-mediated endocytosis. Importantly, lysosomal 3-PIs are needed for growth-factor-induced activities of Akt and mechanistic target of rapamycin complex 1 (mTORC1) on the lysosomal surface, as targeted depletion of 3-PIs has detrimental effects. Thus, 3-PIs, a class of critical lipid second messengers that are typically found in the plasma membrane, unexpectedly accumulate on the lysosomal membrane in response to growth factor stimulation, to direct the multifaceted kinase Akt to organize lysosome-specific signaling.
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Affiliation(s)
- Mingyuan Chen
- Department
of Bioengineering, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
| | - Tengqian Sun
- Department
of Pharmacology, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
| | - Yanghao Zhong
- Department
of Pharmacology, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Xin Zhou
- Department
of Pharmacology, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
| | - Jin Zhang
- Department
of Bioengineering, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
- Department
of Pharmacology, University of California,
San Diego, 9500 Gilman
Drive, La Jolla, California 92093, United States
- Department
of Chemistry & Biochemistry, University
of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
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16
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Su Q, Mehta S, Zhang J. Liquid-liquid phase separation: Orchestrating cell signaling through time and space. Mol Cell 2021; 81:4137-4146. [PMID: 34619090 DOI: 10.1016/j.molcel.2021.09.010] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/16/2021] [Accepted: 09/08/2021] [Indexed: 12/19/2022]
Abstract
Cell signaling is a complex process. The faithful transduction of information into specific cellular actions depends on the synergistic effects of many regulatory molecules, nurtured by their strict spatiotemporal regulation. Over the years, we have gained copious insights into the subcellular architecture supporting this spatiotemporal control, including the roles of membrane-bound organelles and various signaling nanodomains. Recently, liquid-liquid phase separation (LLPS) has been recognized as another potentially ubiquitous framework for organizing signaling molecules with high specificity and precise spatiotemporal control in cells. Here, we review the pervasive role of LLPS in signal transduction, highlighting several key pathways that intersect with LLPS, including examples in which LLPS is controlled by signaling events. We also examine how LLPS orchestrates signaling by compartmentalizing signaling molecules, amplifying signals non-linearly, and moderating signaling dynamics. We focus on the specific molecules that drive LLPS and highlight the known functional and pathological consequences of LLPS in each pathway.
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Affiliation(s)
- Qi Su
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA.
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17
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Lin W, Mo GCH, Mehta S, Zhang J. DrFLINC Contextualizes Super-resolution Activity Imaging. J Am Chem Soc 2021; 143:14951-14955. [PMID: 34516108 DOI: 10.1021/jacs.1c05530] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Super-resolution activity imaging maps the biochemical architecture of living cells yet currently overlooks the locations of collaborating regulators/effectors. Building on the fluorescence fluctuation increase by contact (FLINC) principle, here we devise Dronpa-chromophore-removed FLINC (DrFLINC), where the nonfluorescent Dronpa can nevertheless enhance TagRFP-T fluorescence fluctuations. Exploiting DrFLINC, we develop a superior red label and a next-generation activity sensor for context-rich super-resolution biosensing.
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Affiliation(s)
- Wei Lin
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Gary C H Mo
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States.,Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States.,Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
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18
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Liquid-liquid phase separation: a principal organizer of the cell's biochemical activity architecture. Trends Pharmacol Sci 2021; 42:845-856. [PMID: 34373114 DOI: 10.1016/j.tips.2021.07.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/28/2021] [Accepted: 07/13/2021] [Indexed: 12/25/2022]
Abstract
Numerous processes occur simultaneously in the cell both for normal function and in response to changes in the environment. The ability of cells to segregate biochemical reactions into separate compartments is essential to ensure specificity and efficiency in cellular processes. The discovery of liquid-liquid phase separation as a mechanism of compartmentalization has revised our thinking regarding the intracellular organization of molecular pathways such as signal transduction. Here, we highlight recent studies that advance our understanding of how phase separation impacts the organization of biochemical processes, with a particular focus on the tools used to study the functional impact of phase separation. In addition, we offer some of our perspectives on the pathological consequences of dysregulated phase separation in biochemical pathways.
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