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Ma P, Sternson S, Chen Y. The promise and peril of comparing fluorescence lifetime in biology revealed by simulations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.20.572686. [PMID: 38187652 PMCID: PMC10769356 DOI: 10.1101/2023.12.20.572686] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Signaling dynamics are crucial in biological systems, and biosensor-based real-time imaging has revolutionized their analysis. Fluorescence lifetime imaging microscopy (FLIM) excels over the widely used fluorescence intensity imaging by allowing the measurement of absolute signal levels, independent of sensor concentration. This capability enables the comparison of signaling dynamics across different animals, body regions, and timeframes. However, FLIM's advantage can be compromised by factors like autofluorescence in biological experiments. To address this, we introduce FLiSimBA, a flexible computational framework for realistic F luorescence Li fetime Sim ulation for B iological A pplications. Through simulations, we analyze the signal-to-noise ratios of fluorescence lifetime data, determining measurement uncertainty and providing necessary error bars for lifetime measurements. Furthermore, we challenge the belief that fluorescence lifetime is unaffected by sensor expression and establish quantitative limits to this insensitivity in biological applications. Additionally, we propose innovations, notably multiplexed dynamic imaging that combines fluorescence intensity and lifetime measurements. This innovation can transform the number of signals that can be simultaneously monitored, thereby enabling a systems approach in studying signaling dynamics. Thus, by incorporating diverse factors into our simulation framework, we uncover surprises, identify limitations, and propose advancements for fluorescence lifetime imaging in biology. This quantitative framework supports rigorous experimental design, facilitates accurate data interpretation, and paves the way for technological advancements in fluorescence lifetime imaging.
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2
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Janicot R, Garcia-Marcos M. Get Ready to Sharpen Your Tools: A Short Guide to Heterotrimeric G Protein Activity Biosensors. Mol Pharmacol 2024; 106:129-144. [PMID: 38991745 PMCID: PMC11331509 DOI: 10.1124/molpharm.124.000949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/27/2024] [Accepted: 07/01/2024] [Indexed: 07/13/2024] Open
Abstract
G protein-coupled receptors (GPCRs) are the largest class of transmembrane receptors encoded in the human genome, and they initiate cellular responses triggered by a plethora of extracellular stimuli ranging from neurotransmitters and hormones to photons. Upon stimulation, GPCRs activate heterotrimeric G proteins (Gαβγ) in the cytoplasm, which then convey signals to their effectors to elicit cellular responses. Given the broad biological and biomedical relevance of GPCRs and G proteins in physiology and disease, there is great interest in developing and optimizing approaches to measure their signaling activity with high accuracy and across experimental systems pertinent to their functions in cellular communication. This review provides a historical perspective on approaches to measure GPCR-G protein signaling, from quantification of second messengers and other indirect readouts of activity to biosensors that directly detect the activity of G proteins. The latter is the focus of a more detailed overview of the evolution of design principles for various optical biosensors of G protein activity with different experimental capabilities. We will highlight advantages and limitations of biosensors that detect different G protein activation hallmarks, like dissociation of Gα and Gβγ or nucleotide exchange on Gα, as well as their suitability to detect signaling mediated by endogenous versus exogenous signaling components or in physiologically relevant systems like primary cells. Overall, this review intends to provide an assessment of the state-of-the-art for biosensors that directly measure G protein activity to allow readers to make informed decisions on the selection and implementation of currently available tools. SIGNIFICANCE STATEMENT: G protein activity biosensors have become essential and widespread tools to assess GPCR signaling and pharmacology. Yet, investigators face the challenge of choosing from a growing list of G protein activity biosensors. This review provides an overview of the features and capabilities of different optical biosensor designs for the direct detection of G protein activity in cells, with the aim of facilitating the rational selection of systems that align with the specific scientific questions and needs of investigators.
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Affiliation(s)
- Remi Janicot
- Department of Biochemistry & Cell Biology, Chobanian & Avedisian School of Medicine (R.J., M.G.-M.) and Department of Biology, College of Arts & Sciences (M.G.-M.), Boston University, Boston, Massachusetts
| | - Mikel Garcia-Marcos
- Department of Biochemistry & Cell Biology, Chobanian & Avedisian School of Medicine (R.J., M.G.-M.) and Department of Biology, College of Arts & Sciences (M.G.-M.), Boston University, Boston, Massachusetts
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3
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Ma P, Chen P, Tilden EI, Aggarwal S, Oldenborg A, Chen Y. Fast and slow: Recording neuromodulator dynamics across both transient and chronic time scales. SCIENCE ADVANCES 2024; 10:eadi0643. [PMID: 38381826 PMCID: PMC10881037 DOI: 10.1126/sciadv.adi0643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 01/17/2024] [Indexed: 02/23/2024]
Abstract
Neuromodulators transform animal behaviors. Recent research has demonstrated the importance of both sustained and transient change in neuromodulators, likely due to tonic and phasic neuromodulator release. However, no method could simultaneously record both types of dynamics. Fluorescence lifetime of optical reporters could offer a solution because it allows high temporal resolution and is impervious to sensor expression differences across chronic periods. Nevertheless, no fluorescence lifetime change across the entire classes of neuromodulator sensors was previously known. Unexpectedly, we find that several intensity-based neuromodulator sensors also exhibit fluorescence lifetime responses. Furthermore, we show that lifetime measures in vivo neuromodulator dynamics both with high temporal resolution and with consistency across animals and time. Thus, we report a method that can simultaneously measure neuromodulator change over transient and chronic time scales, promising to reveal the roles of multi-time scale neuromodulator dynamics in diseases, in response to therapies, and across development and aging.
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Affiliation(s)
- Pingchuan Ma
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
- Ph.D. Program in Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - Peter Chen
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
- Master’s Program in Biomedical Engineering, Washington University, St. Louis, MO 63110, USA
| | - Elizabeth I. Tilden
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
- Ph.D. Program in Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - Samarth Aggarwal
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - Anna Oldenborg
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - Yao Chen
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
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4
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Tilden EI, Maduskar A, Oldenborg A, Sabatini BL, Chen Y. A Cre-dependent reporter mouse for quantitative real-time imaging of protein kinase A activity dynamics. Sci Rep 2024; 14:3054. [PMID: 38321128 PMCID: PMC10847463 DOI: 10.1038/s41598-024-53313-8] [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: 11/17/2023] [Accepted: 01/30/2024] [Indexed: 02/08/2024] Open
Abstract
Intracellular signaling dynamics play a crucial role in cell function. Protein kinase A (PKA) is a key signaling molecule that has diverse functions, from regulating metabolism and brain activity to guiding development and cancer progression. We previously developed an optical reporter, FLIM-AKAR, that allows for quantitative imaging of PKA activity via fluorescence lifetime imaging microscopy and photometry. However, using viral infection or electroporation for the delivery of FLIM-AKAR is invasive and results in variable expression. Here, we developed a reporter mouse, FL-AK, which expresses FLIM-AKAR in a Cre-dependent manner from the ROSA26 locus. FL-AK provides robust and consistent expression of FLIM-AKAR over time. Functionally, the mouse line reports an increase in PKA activity in response to activation of both Gαs and Gαq-coupled receptors in brain slices. In vivo, FL-AK reports PKA phosphorylation in response to neuromodulator receptor activation. Thus, FL-AK provides a quantitative, robust, and flexible method to reveal the dynamics of PKA activity in diverse cell types.
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Affiliation(s)
- Elizabeth I Tilden
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
- Ph.D. Program in Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | - Aditi Maduskar
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | - Anna Oldenborg
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | - Bernardo L Sabatini
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Yao Chen
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA.
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5
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Fessl T, Majellaro M, Bondar A. Microscopy and spectroscopy approaches to study GPCR structure and function. Br J Pharmacol 2023. [PMID: 38087925 DOI: 10.1111/bph.16297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 11/03/2023] [Accepted: 11/30/2023] [Indexed: 01/05/2024] Open
Abstract
The GPCR signalling cascade is a key pathway responsible for the signal transduction of a multitude of physical and chemical stimuli, including light, odorants, neurotransmitters and hormones. Understanding the structural and functional properties of the GPCR cascade requires direct observation of signalling processes in high spatial and temporal resolution, with minimal perturbation to endogenous systems. Optical microscopy and spectroscopy techniques are uniquely suited to this purpose because they excel at multiple spatial and temporal scales and can be used in living objects. Here, we review recent developments in microscopy and spectroscopy technologies which enable new insights into GPCR signalling. We focus on advanced techniques with high spatial and temporal resolution, single-molecule methods, labelling strategies and approaches suitable for endogenous systems and large living objects. This review aims to assist researchers in choosing appropriate microscopy and spectroscopy approaches for a variety of applications in the study of cellular signalling.
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Affiliation(s)
- Tomáš Fessl
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | | | - Alexey Bondar
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- Laboratory of Microscopy and Histology, Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
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6
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Tilden EI, Maduskar A, Oldenborg A, Sabatini BL, Chen Y. A Cre-dependent reporter mouse for quantitative real-time imaging of Protein Kinase A activity dynamics. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.31.565028. [PMID: 37961214 PMCID: PMC10635033 DOI: 10.1101/2023.10.31.565028] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Intracellular signaling dynamics play a crucial role in cell function. Protein kinase A (PKA) is a key signaling molecule that has diverse functions, from regulating metabolism and brain activity to guiding development and cancer progression. We previously developed an optical reporter, FLIM-AKAR, that allows for quantitative imaging of PKA activity via fluorescence lifetime imaging microscopy and photometry. However, using viral infection or electroporation for the delivery of FLIM-AKAR is invasive, cannot easily target sparse or hard-to-transfect/infect cell types, and results in variable expression. Here, we developed a reporter mouse, FL-AK, which expresses FLIM-AKAR in a Cre-dependent manner from the ROSA26 locus. FL-AK provides robust and consistent expression of FLIM-AKAR over time. Functionally, the mouse line reports an increase in PKA activity in response to activation of both Gαs and Gαq-coupled receptors in brain slices. In vivo, FL-AK reports PKA phosphorylation in response to neuromodulator receptor activation. Thus, FL-AK provides a quantitative, robust, and flexible method to reveal the dynamics of PKA activity in diverse cell types.
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Affiliation(s)
- Elizabeth I. Tilden
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States
- Ph. D. Program in Neuroscience, Washington University in St. Louis
| | - Aditi Maduskar
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States
| | - Anna Oldenborg
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States
| | - Bernardo L. Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
| | - Yao Chen
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States
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7
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Vu CQ, Arai S. Quantitative Imaging of Genetically Encoded Fluorescence Lifetime Biosensors. BIOSENSORS 2023; 13:939. [PMID: 37887132 PMCID: PMC10605767 DOI: 10.3390/bios13100939] [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: 09/05/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023]
Abstract
Genetically encoded fluorescence lifetime biosensors have emerged as powerful tools for quantitative imaging, enabling precise measurement of cellular metabolites, molecular interactions, and dynamic cellular processes. This review provides an overview of the principles, applications, and advancements in quantitative imaging with genetically encoded fluorescence lifetime biosensors using fluorescence lifetime imaging microscopy (go-FLIM). We highlighted the distinct advantages of fluorescence lifetime-based measurements, including independence from expression levels, excitation power, and focus drift, resulting in robust and reliable measurements compared to intensity-based approaches. Specifically, we focus on two types of go-FLIM, namely Förster resonance energy transfer (FRET)-FLIM and single-fluorescent protein (FP)-based FLIM biosensors, and discuss their unique characteristics and benefits. This review serves as a valuable resource for researchers interested in leveraging fluorescence lifetime imaging to study molecular interactions and cellular metabolism with high precision and accuracy.
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Affiliation(s)
- Cong Quang Vu
- WPI Nano Life Science Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Satoshi Arai
- WPI Nano Life Science Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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8
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Jong YJI, Izumi Y, Harmon SK, Zorumski CF, ÓMalley KL. Striatal mGlu 5-mediated synaptic plasticity is independently regulated by location-specific receptor pools and divergent signaling pathways. J Biol Chem 2023; 299:104949. [PMID: 37354970 PMCID: PMC10388212 DOI: 10.1016/j.jbc.2023.104949] [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: 02/13/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/26/2023] Open
Abstract
Metabotropic glutamate receptor 5 (mGlu5) is widely expressed throughout the central nervous system and is involved in neuronal function, synaptic transmission, and a number of neuropsychiatric disorders such as depression, anxiety, and autism. Recent work from this lab showed that mGlu5 is one of a growing number of G protein-coupled receptors that can signal from intracellular membranes where it drives unique signaling pathways, including upregulation of extracellular signal-regulated kinase (ERK1/2), ETS transcription factor Elk-1, and activity-regulated cytoskeleton-associated protein (Arc). To determine the roles of cell surface mGlu5 as well as the intracellular receptor in a well-known mGlu5 synaptic plasticity model such as long-term depression, we used pharmacological isolation and genetic and physiological approaches to analyze spatially restricted pools of mGlu5 in striatal cultures and slice preparations. Here we show that both intracellular and cell surface receptors activate the phosphatidylinositol-3-kinase-protein kinase B-mammalian target of rapamycin (PI3K/AKT/mTOR) pathway, whereas only intracellular mGlu5 activates protein phosphatase 2 and leads to fragile X mental retardation protein degradation and de novo protein synthesis followed by a protein synthesis-dependent increase in Arc and post-synaptic density protein 95. However, both cell surface and intracellular mGlu5 activation lead to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor GluA2 internalization and chemically induced long-term depression albeit via different signaling mechanisms. These data underscore the importance of intracellular mGlu5 in the cascade of events associated with sustained synaptic transmission in the striatum.
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Affiliation(s)
- Yuh-Jiin I Jong
- Department of Neuroscience, Washington University School of Medicine, St Louis, Missouri, USA
| | - Yukitoshi Izumi
- Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St Louis, Missouri, USA
| | - Steven K Harmon
- Department of Neuroscience, Washington University School of Medicine, St Louis, Missouri, USA
| | - Charles F Zorumski
- Department of Neuroscience, Washington University School of Medicine, St Louis, Missouri, USA; Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St Louis, Missouri, USA
| | - Karen L ÓMalley
- Department of Neuroscience, Washington University School of Medicine, St Louis, Missouri, USA.
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Farrants H, Shuai Y, Lemon WC, Hernandez CM, Yang S, Patel R, Qiao G, Frei MS, Grimm JB, Hanson TL, Tomaska F, Turner GC, Stringer C, Keller PJ, Beyene AG, Chen Y, Liang Y, Lavis LD, Schreiter ER. A modular chemigenetic calcium indicator enables in vivo functional imaging with near-infrared light. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.18.549527. [PMID: 37503182 PMCID: PMC10370049 DOI: 10.1101/2023.07.18.549527] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Genetically encoded fluorescent calcium indicators have revolutionized neuroscience and other biological fields by allowing cellular-resolution recording of physiology during behavior. However, we currently lack bright, genetically targetable indicators in the near infrared that can be used in animals. Here, we describe WHaloCaMP, a modular chemigenetic calcium indicator built from bright dye-ligands and protein sensor domains that can be genetically targeted to specific cell populations. Fluorescence change in WHaloCaMP results from reversible quenching of the bound dye via a strategically placed tryptophan. WHaloCaMP is compatible with rhodamine dye-ligands that fluoresce from green to near-infrared, including several dye-ligands that efficiently label the central nervous system in animals. When bound to a near-infrared dye-ligand, WHaloCaMP1a is more than twice as bright as jGCaMP8s, and shows a 7× increase in fluorescence intensity and a 2.1 ns increase in fluorescence lifetime upon calcium binding. We use WHaloCaMP1a with near-infrared fluorescence emission to image Ca2+ responses in flies and mice, to perform three-color multiplexed functional imaging of hundreds of neurons and astrocytes in zebrafish larvae, and to quantitate calcium concentration using fluorescence lifetime imaging microscopy (FLIM).
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Affiliation(s)
- Helen Farrants
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Yichun Shuai
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - William C Lemon
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Shang Yang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ronak Patel
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Guanda Qiao
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Michelle S Frei
- Department of Chemical Biology, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Jonathan B Grimm
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Timothy L Hanson
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Filip Tomaska
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Glenn C Turner
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Carsen Stringer
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Philipp J Keller
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Abraham G Beyene
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Yao Chen
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Yajie Liang
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Luke D Lavis
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Eric R Schreiter
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
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10
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Brown JA, Petersen N, Centanni SW, Jin AY, Yoon HJ, Cajigas SA, Bedenbaugh MN, Luchsinger JR, Patel S, Calipari ES, Simerly RB, Winder DG. An ensemble recruited by α 2a-adrenergic receptors is engaged in a stressor-specific manner in mice. Neuropsychopharmacology 2023; 48:1133-1143. [PMID: 36085168 PMCID: PMC10267140 DOI: 10.1038/s41386-022-01442-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/17/2022] [Accepted: 08/22/2022] [Indexed: 11/08/2022]
Abstract
α2a-adrenergic receptor (α2a-AR) agonists are candidate substance use disorder therapeutics due to their ability to recruit noradrenergic autoreceptors to dampen stress system engagement. However, we recently found that postsynaptic α2a-ARs are required for stress-induced reinstatement of cocaine-conditioned behavior. Understanding the ensembles recruited by these postsynaptic receptors (heteroceptors) is necessary to understand noradrenergic circuit control. We utilized a variety of approaches in FosTRAP (Targeted Recombination in Active Populations) mice to define an ensemble of cells activated by the α2a-AR partial agonist guanfacine ("Guansembles") in the bed nucleus of the stria terminalis (BST/BNST), a region key to stress-induced reinstatement of drug seeking. We define BNST "Guansembles" and show they differ from restraint stress-activated cells. Guanfacine produced inhibition of cAMP-dependent signaling in Guansembles, while chronic restraint stress increased cAMP-dependent signaling. Guanfacine both excited and inhibited aspects of Guansemble neuronal activity. Further, while some stressors produced overall reductions in Guansemble activity, active coping events during restraint stress and exposure to unexpected shocks were both associated with Guansemble recruitment. Using viral tracing, we define a BNST Guansemble afferent network that includes regions involved in the interplay of stress and homeostatic functions. Finally, we show that activation of Guansembles produces alterations in behavior on the elevated plus maze consistent with task-specific anxiety-like behavior. Overall, we define a population of BNST neurons recruited by α2a-AR signaling that opposes the behavioral action of canonical autoreceptor α2a-AR populations and which are differentially recruited by distinct stressors. Moreover, we demonstrate stressor-specific physiological responses in a specific neuronal population.
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Affiliation(s)
- Jordan A Brown
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
| | - Nicholas Petersen
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Samuel W Centanni
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Allie Y Jin
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
| | - Hye Jean Yoon
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Stephanie A Cajigas
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Michelle N Bedenbaugh
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Joseph R Luchsinger
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Sachin Patel
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Erin S Calipari
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Richard B Simerly
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Danny G Winder
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, USA.
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA.
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA.
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11
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Jia J, Tang S, Yue X, Jing S, Zhu L, Tan C, Gao J, Du Y, Lee I, Qian Y. An A-Kinase Anchoring Protein (ACBD3) Coordinates Traffic-Induced PKA Activation At The Golgi. J Biol Chem 2023; 299:104696. [PMID: 37044218 DOI: 10.1016/j.jbc.2023.104696] [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: 10/12/2022] [Revised: 03/23/2023] [Accepted: 03/25/2023] [Indexed: 04/14/2023] Open
Abstract
KDEL receptor (KDELR) is a key protein that recycles escaped ER resident proteins from the Golgi apparatus back to the ER and maintains a dynamic balance between these two organelles in the early secretory pathway. Studies have shown that this retrograde transport pathway is partly regulated by two KDELR-interacting proteins, Acyl-CoA-binding domain-containing 3 (ACBD3), and cyclic AMP-dependent protein kinase A (PKA). However, whether Golgi-localized ACBD3, which was first discovered as a PKA-anchoring protein in mitochondria, directly interacts with PKA at the Golgi and coordinates its signaling in Golgi-to-ER traffic has remained unclear. In this study, we showed that the GOLD domain of ACBD3 directly interacts with the regulatory subunit II (RII) of PKA and effectively recruits PKA holoenzyme to the Golgi. Forward trafficking of proteins from the ER triggers activation of PKA by releasing the catalytic subunit from RII. Furthermore, we determined that depletion of ACBD3 reduces the Golgi fraction of RII, resulting in moderate, but constitutive activation of PKA and KDELR retrograde transport, independent of cargo influx from the ER. Taken together, these data demonstrate that ACBD3 coordinates the protein secretory pathway at the Golgi by facilitating KDELR/PKA-containing protein complex formation.
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Affiliation(s)
- Jie Jia
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Shuocheng Tang
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Xihua Yue
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Shuaiyang Jing
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Lianhui Zhu
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Chuanting Tan
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jingkai Gao
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yulei Du
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
| | - Intaek Lee
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.
| | - Yi Qian
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.
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12
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Savory Signaling: T1R Umami Receptor Modulates Endoplasmic Reticulum Calcium Store Content and Release Dynamics in Airway Epithelial Cells. Nutrients 2023; 15:nu15030493. [PMID: 36771200 PMCID: PMC9919336 DOI: 10.3390/nu15030493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/10/2023] [Accepted: 01/16/2023] [Indexed: 01/19/2023] Open
Abstract
T1Rs are expressed in solitary chemosensory cells of the upper airway where they detect apical glucose levels and repress bitter taste receptor Ca2+ signaling pathways. Microbial growth leads to a decrease in apical glucose levels. T1Rs detect this change and liberate bitter taste receptor signaling, initiating an innate immune response to both kill and expel pathogens through releasing antimicrobial peptides and increasing nitric oxide production and ciliary beat frequency. However, chronic inflammation due to disease, smoking, or viral infections causes a remodeling of the epithelial airway. The resulting squamous metaplasia causes a loss of multi-ciliated cells and solitary chemosensory cells, replaced by basal epithelial cells. To understand how T1R function is altered during disease, we used basal epithelial cells as a model to study the function of T1R3 on Ca2+ signaling dynamics. We found that both T1R1 and T1R3 detect amino acids and signal via cAMP, increasing the responsiveness of the cells to Ca2+ signaling stimuli. Either knocking down T1R1/3 or treating wild-type cells with MEM amino acids caused a reduction in ER Ca2+ content through a non-cAMP signaled pathway. Treatment with amino acids led to a reduction in downstream denatonium-induced Ca2+-signaled caspase activity. Thus, amino acids may be used to reduce unwanted apoptosis signaling in treatments containing bitter compounds.
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13
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Lovinger DM, Mateo Y, Johnson KA, Engi SA, Antonazzo M, Cheer JF. Local modulation by presynaptic receptors controls neuronal communication and behaviour. Nat Rev Neurosci 2022; 23:191-203. [PMID: 35228740 PMCID: PMC10709822 DOI: 10.1038/s41583-022-00561-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 12/15/2022]
Abstract
Central nervous system neurons communicate via fast synaptic transmission mediated by ligand-gated ion channel (LGIC) receptors and slower neuromodulation mediated by G protein-coupled receptors (GPCRs). These receptors influence many neuronal functions, including presynaptic neurotransmitter release. Presynaptic LGIC and GPCR activation by locally released neurotransmitters influences neuronal communication in ways that modify effects of somatic action potentials. Although much is known about presynaptic receptors and their mechanisms of action, less is known about when and where these receptor actions alter release, especially in vivo. This Review focuses on emerging evidence for important local presynaptic receptor actions and ideas for future studies in this area.
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Affiliation(s)
- David M Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA.
| | - Yolanda Mateo
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA
| | - Kari A Johnson
- Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Sheila A Engi
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mario Antonazzo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joseph F Cheer
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
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14
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Kocik RA, Gasch AP. Breadth and Specificity in Pleiotropic Protein Kinase A Activity and Environmental Responses. Front Cell Dev Biol 2022; 10:803392. [PMID: 35252178 PMCID: PMC8888911 DOI: 10.3389/fcell.2022.803392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 02/03/2022] [Indexed: 11/13/2022] Open
Abstract
Protein Kinase A (PKA) is an essential kinase that is conserved across eukaryotes and plays fundamental roles in a wide range of organismal processes, including growth control, learning and memory, cardiovascular health, and development. PKA mediates these responses through the direct phosphorylation of hundreds of proteins-however, which proteins are phosphorylated can vary widely across cell types and environmental cues, even within the same organism. A major question is how cells enact specificity and precision in PKA activity to mount the proper response, especially during environmental changes in which only a subset of PKA-controlled processes must respond. Research over the years has uncovered multiple strategies that cells use to modulate PKA activity and specificity. This review highlights recent advances in our understanding of PKA signaling control including subcellular targeting, phase separation, feedback control, and standing waves of allosteric regulation. We discuss how the complex inputs and outputs to the PKA network simultaneously pose challenges and solutions in signaling integration and insulation. PKA serves as a model for how the same regulatory factors can serve broad pleiotropic functions but maintain specificity in localized control.
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Affiliation(s)
- Rachel A Kocik
- Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI, United States.,Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI, United States
| | - Audrey P Gasch
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI, United States.,Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, United States
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15
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Abstract
Fluorescent protein (FP)-based kinase activity biosensors are powerful tools for probing the spatiotemporal dynamics of signaling pathways in living cells. Yet, the limited sensitivity of most kinase biosensors restricts their reliable application in high-throughput detection modalities. Here, we report a protocol for using an ultrasensitive excitation-ratiometric PKA activity reporter, ExRai-AKAR2, to detect live-cell PKA activity via fluorescence microplate reading and epifluorescence microscopy. The high sensitivity of ExRai-AKAR2 is well suited to these high-throughput applications. For complete details on the use and execution of this protocol, please refer to Mehta et al. (2018) andZhang et al., 2021a) .
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Affiliation(s)
- Jin-fan 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,Corresponding author
| | - 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,Corresponding author
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16
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Ovechkina VS, Zakian SM, Medvedev SP, Valetdinova KR. Genetically Encoded Fluorescent Biosensors for Biomedical Applications. Biomedicines 2021; 9:biomedicines9111528. [PMID: 34829757 PMCID: PMC8615007 DOI: 10.3390/biomedicines9111528] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 11/16/2022] Open
Abstract
One of the challenges of modern biology and medicine is to visualize biomolecules in their natural environment, in real-time and in a non-invasive fashion, so as to gain insight into their physiological behavior and highlight alterations in pathological settings, which will enable to devise appropriate therapeutic strategies. Genetically encoded fluorescent biosensors constitute a class of imaging agents that enable visualization of biological processes and events directly in situ, preserving the native biological context and providing detailed insight into their localization and dynamics in cells. Real-time monitoring of drug action in a specific cellular compartment, organ, or tissue type; the ability to screen at the single-cell resolution; and the elimination of false-positive results caused by low drug bioavailability that is not detected by in vitro testing methods are a few of the obvious benefits of using genetically encoded fluorescent biosensors in drug screening. This review summarizes results of the studies that have been conducted in the last years toward the fabrication of genetically encoded fluorescent biosensors for biomedical applications with a comprehensive discussion on the challenges, future trends, and potential inputs needed for improving them.
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Affiliation(s)
- Vera S. Ovechkina
- The Federal Research Center Institute of Cytology and Genetics, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (V.S.O.); (S.M.Z.); (S.P.M.)
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Suren M. Zakian
- The Federal Research Center Institute of Cytology and Genetics, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (V.S.O.); (S.M.Z.); (S.P.M.)
- E.N. Meshalkin National Medical Research Center, Ministry of Health of the Russian Federation, 630055 Novosibirsk, Russia
- Institute of Chemical Biology and Fundamental Medicine, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Sergey P. Medvedev
- The Federal Research Center Institute of Cytology and Genetics, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (V.S.O.); (S.M.Z.); (S.P.M.)
- E.N. Meshalkin National Medical Research Center, Ministry of Health of the Russian Federation, 630055 Novosibirsk, Russia
- Institute of Chemical Biology and Fundamental Medicine, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Kamila R. Valetdinova
- The Federal Research Center Institute of Cytology and Genetics, The Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (V.S.O.); (S.M.Z.); (S.P.M.)
- E.N. Meshalkin National Medical Research Center, Ministry of Health of the Russian Federation, 630055 Novosibirsk, Russia
- Correspondence:
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17
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Lodder B, Lee SJ, Sabatini BL. Real-Time, In Vivo Measurement of Protein Kinase A Activity in Deep Brain Structures Using Fluorescence Lifetime Photometry (FLiP). Curr Protoc 2021; 1:e265. [PMID: 34661994 DOI: 10.1002/cpz1.265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The biochemical state of neurons, and of cells in general, is regulated by extracellular factors, including neurotransmitters, neuromodulators, and growth hormones. Interactions of an animal with its environment trigger neuromodulator release and engage biochemical transduction cascades to modulate synapse and cell function. Although these processes are thought to enact behavioral adaption to changing environments, when and where in the brain they are induced has been mysterious because of the challenge of monitoring biochemical state in real time in defined neurons in behaving animals. Here, we describe a method allowing measurement of activity of protein kinase A (PKA), an important intracellular effector for neuromodulators, in freely moving mice. To monitor PKA activity in vivo, we use a genetically targeted sensor (FLIM-AKAR) and fluorescence lifetime photometry (FLiP). This article describes how to set up a FLiP system and obtain robust recordings of net PKA phosphorylation state in vivo. The methods should be generally useful to monitor other pathways for which fluorescence lifetime reporters exist. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Building a FLiP system Basic Protocol 2: FLIM-AKAR viral injection and fiber implantation for FLiP measurement Basic Protocol 3: Performing measurements using FLiP.
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Affiliation(s)
- Bart Lodder
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, Massachusetts.,Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Boston, Massachusetts
| | - Suk Joon Lee
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, Massachusetts
| | - Bernardo L Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, Massachusetts
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18
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Imaging intracellular protein interactions/activity in neurons using 2-photon fluorescence lifetime imaging microscopy. Neurosci Res 2021; 179:31-38. [PMID: 34666101 DOI: 10.1016/j.neures.2021.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 12/23/2022]
Abstract
Through the decades, 2-photon fluorescence microscopy has allowed visualization of microstructures, such as synapses, with high spatial resolution in deep brain tissue. However, signal transduction, such as protein activity and protein-protein interaction in neurons in tissues and in vivo, has remained elusive because of the technical difficulty of observing biochemical reactions at the level of subcellular resolution in light-scattering tissues. Recently, 2-photon fluorescence microscopy combined with fluorescence lifetime imaging microscopy (2pFLIM) has enabled visualization of various protein activities and protein-protein interactions at submicrometer resolution in tissue with a reasonable temporal resolution. Thus far, 2pFLIM has been extensively applied for imaging kinase and small GTPase activation in dendritic spines of hippocampal neurons in slice cultures. However, it has been recently applied to various subcellular structures, such as axon terminals and nuclei, and has increased our understanding of spatially organized molecular dynamics. One of the future directions of 2pFLIM utilization is to combine various optogenetic tools for manipulating protein activity. This combination allows the activation of specific proteins with light and visualization of its readout as the activation of downstream molecules. Here, we have introduced the recent application of 2pFLIM for neurons and present the utilization of a new optogenetic tool in combination with 2pFLIM.
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19
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Islam MMT, Tarnowski D, Zhang M, Trum M, Lebek S, Mustroph J, Daniel H, Moellencamp J, Pabel S, Sossalla S, El‐Armouche A, Nikolaev VO, Shah AM, Eaton P, Maier LS, Sag CM, Wagner S. Enhanced Heart Failure in Redox-Dead Cys17Ser PKARIα Knock-In Mice. J Am Heart Assoc 2021; 10:e021985. [PMID: 34583520 PMCID: PMC8649132 DOI: 10.1161/jaha.121.021985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Background PKARIα (protein kinase A type I-α regulatory subunit) is redox-active independent of its physiologic agonist cAMP. However, it is unknown whether this alternative mechanism of PKARIα activation may be of relevance to cardiac excitation-contraction coupling. Methods and Results We used a redox-dead transgenic mouse model with homozygous knock-in replacement of redox-sensitive cysteine 17 with serine within the regulatory subunits of PKARIα (KI). Reactive oxygen species were acutely evoked by exposure of isolated cardiac myocytes to AngII (angiotensin II, 1 µmol/L). The long-term relevance of oxidized PKARIα was investigated in KI mice and their wild-type (WT) littermates following transverse aortic constriction (TAC). AngII increased reactive oxygen species in both groups but with RIα dimer formation in WT only. AngII induced translocation of PKARI to the cell membrane and resulted in protein kinase A-dependent stimulation of ICa (L-type Ca current) in WT with no effect in KI myocytes. Consequently, Ca transients were reduced in KI myocytes as compared with WT cells following acute AngII exposure. Transverse aortic constriction-related reactive oxygen species formation resulted in RIα oxidation in WT but not in KI mice. Within 6 weeks after TAC, KI mice showed an enhanced deterioration of contractile function and impaired survival compared with WT. In accordance, compared with WT, ventricular myocytes from failing KI mice displayed significantly reduced Ca transient amplitudes and lack of ICa stimulation. Conversely, direct pharmacological stimulation of ICa using Bay K8644 rescued Ca transients in AngII-treated KI myocytes and contractile function in failing KI mice in vivo. Conclusions Oxidative activation of PKARIα with subsequent stimulation of ICa preserves cardiac function in the setting of acute and chronic oxidative stress.
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Affiliation(s)
- M. M. Towhidul Islam
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
- Department of Biochemistry and Molecular BiologyUniversity of DhakaBangladesh
| | - Daniel Tarnowski
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Min Zhang
- School of Cardiovascular Medicine & SciencesKings College London British Heart Foundation Centre of ExcellenceLondonUnited Kingdom
| | - Maximilian Trum
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Simon Lebek
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Julian Mustroph
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Henriette Daniel
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Johanna Moellencamp
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Steffen Pabel
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Samuel Sossalla
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Ali El‐Armouche
- Department of Pharmacology and ToxicologyTechnical University DresdenDresdenGermany
| | - Viacheslav O. Nikolaev
- Institute of Experimental Cardiovascular ResearchUniversity Medical Center Hamburg‐EppendorfEppendorfGermany
| | - Ajay M. Shah
- School of Cardiovascular Medicine & SciencesKings College London British Heart Foundation Centre of ExcellenceLondonUnited Kingdom
| | - Philip Eaton
- The William Harvey Research InstituteBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUnited Kingdom
| | - Lars S. Maier
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Can Martin Sag
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Stefan Wagner
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
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20
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Massengill CI, Day-Cooney J, Mao T, Zhong H. Genetically encoded sensors towards imaging cAMP and PKA activity in vivo. J Neurosci Methods 2021; 362:109298. [PMID: 34339753 PMCID: PMC8659126 DOI: 10.1016/j.jneumeth.2021.109298] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/22/2021] [Accepted: 07/29/2021] [Indexed: 12/26/2022]
Abstract
Cyclic adenosine monophosphate (cAMP) is a universal second messenger that plays a crucial role in diverse biological functions, ranging from transcription to neuronal plasticity, and from development to learning and memory. In the nervous system, cAMP integrates inputs from many neuromodulators across a wide range of timescales - from seconds to hours - to modulate neuronal excitability and plasticity in brain circuits during different animal behavioral states. cAMP signaling events are both cell-specific and subcellularly compartmentalized. The same stimulus may result in different, sometimes opposite, cAMP dynamics in different cells or subcellular compartments. Additionally, the activity of protein kinase A (PKA), a major cAMP effector, is also spatiotemporally regulated. For these reasons, many laboratories have made great strides toward visualizing the intracellular dynamics of cAMP and PKA. To date, more than 80 genetically encoded sensors, including original and improved variants, have been published. It is starting to become possible to visualize cAMP and PKA signaling events in vivo, which is required to study behaviorally relevant cAMP/PKA signaling mechanisms. Despite significant progress, further developments are needed to enhance the signal-to-noise ratio and practical utility of these sensors. This review summarizes the recent advances and challenges in genetically encoded cAMP and PKA sensors with an emphasis on in vivo imaging in the brain during behavior.
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Affiliation(s)
| | - Julian Day-Cooney
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Tianyi Mao
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Haining Zhong
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
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21
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Woodall NB, Weinberg Z, Park J, Busch F, Johnson RS, Feldbauer MJ, Murphy M, Ahlrichs M, Yousif I, MacCoss MJ, Wysocki VH, El-Samad H, Baker D. De novo design of tyrosine and serine kinase-driven protein switches. Nat Struct Mol Biol 2021; 28:762-770. [PMID: 34518698 PMCID: PMC8601088 DOI: 10.1038/s41594-021-00649-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 07/26/2021] [Indexed: 02/07/2023]
Abstract
Kinases play central roles in signaling cascades, relaying information from the outside to the inside of mammalian cells. De novo designed protein switches capable of interfacing with tyrosine kinase signaling pathways would open new avenues for controlling cellular behavior, but, so far, no such systems have been described. Here we describe the de novo design of two classes of protein switch that link phosphorylation by tyrosine and serine kinases to protein-protein association. In the first class, protein-protein association is required for phosphorylation by the kinase, while in the second class, kinase activity drives protein-protein association. We design systems that couple protein binding to kinase activity on the immunoreceptor tyrosine-based activation motif central to T-cell signaling, and kinase activity to reconstitution of green fluorescent protein fluorescence from fragments and the inhibition of the protease calpain. The designed switches are reversible and function in vitro and in cells with up to 40-fold activation of switching by phosphorylation.
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Affiliation(s)
- Nicholas B Woodall
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Zara Weinberg
- Department of Biochemistry & Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Jesslyn Park
- Department of Biochemistry & Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Florian Busch
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH, USA
| | - Richard S Johnson
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | | | - Michael Murphy
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Maggie Ahlrichs
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Issa Yousif
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Vicki H Wysocki
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH, USA
| | - Hana El-Samad
- Department of Biochemistry & Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA.
- Institute for Protein Design, University of Washington, Seattle, WA, USA.
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22
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Zhang SX, Lutas A, Yang S, Diaz A, Fluhr H, Nagel G, Gao S, Andermann ML. Hypothalamic dopamine neurons motivate mating through persistent cAMP signalling. Nature 2021; 597:245-249. [PMID: 34433964 DOI: 10.1038/s41586-021-03845-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 07/21/2021] [Indexed: 12/11/2022]
Abstract
Transient neuromodulation can have long-lasting effects on neural circuits and motivational states1-4. Here we examine the dopaminergic mechanisms that underlie mating drive and its persistence in male mice. Brief investigation of females primes a male's interest to mate for tens of minutes, whereas a single successful mating triggers satiety that gradually recovers over days5. We found that both processes are controlled by specialized anteroventral and preoptic periventricular (AVPV/PVpo) dopamine neurons in the hypothalamus. During the investigation of females, dopamine is transiently released in the medial preoptic area (MPOA)-an area that is critical for mating behaviours. Optogenetic stimulation of AVPV/PVpo dopamine axons in the MPOA recapitulates the priming effect of exposure to a female. Using optical and molecular methods for tracking and manipulating intracellular signalling, we show that this priming effect emerges from the accumulation of mating-related dopamine signals in the MPOA through the accrual of cyclic adenosine monophosphate levels and protein kinase A activity. Dopamine transients in the MPOA are abolished after a successful mating, which is likely to ensure abstinence. Consistent with this idea, the inhibition of AVPV/PVpo dopamine neurons selectively demotivates mating, whereas stimulating these neurons restores the motivation to mate after sexual satiety. We therefore conclude that the accumulation or suppression of signals from specialized dopamine neurons regulates mating behaviours across minutes and days.
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Affiliation(s)
- Stephen X Zhang
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Andrew Lutas
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Shang Yang
- Institute of Physiology, Department of Neurophysiology, Biocenter, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Adriana Diaz
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Hugo Fluhr
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Georg Nagel
- Institute of Physiology, Department of Neurophysiology, Biocenter, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Shiqiang Gao
- Institute of Physiology, Department of Neurophysiology, Biocenter, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Mark L Andermann
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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23
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Cellular context shapes cyclic nucleotide signaling in neurons through multiple levels of integration. J Neurosci Methods 2021; 362:109305. [PMID: 34343574 DOI: 10.1016/j.jneumeth.2021.109305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/22/2021] [Accepted: 07/29/2021] [Indexed: 02/06/2023]
Abstract
Intracellular signaling with cyclic nucleotides are ubiquitous signaling pathways, yet the dynamics of these signals profoundly differ in different cell types. Biosensor imaging experiments, by providing direct measurements in intact cellular environment, reveal which receptors are activated by neuromodulators and how the coincidence of different neuromodulators is integrated at various levels in the signaling cascade. Phosphodiesterases appear as one important determinant of cross-talk between different signaling pathways. Finally, analysis of signal dynamics reveal that striatal medium-sized spiny neuron obey a different logic than other brain regions such as cortex, probably in relation with the function of this brain region which efficiently detects transient dopamine.
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24
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Lafferty CK, Christinck TD, Britt JP. All-optical approaches to studying psychiatric disease. Methods 2021; 203:46-55. [PMID: 34314828 DOI: 10.1016/j.ymeth.2021.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 11/17/2022] Open
Abstract
Improvements in all-optical means of monitoring and manipulating neural activity have generated new ways of studying psychiatric disease. The combination of calcium imaging techniques with optogenetics to concurrently record and manipulate neural activity has been used to create new disease models that link distinct circuit abnormalities to specific disease dimensions. These approaches represent a new path towards the development of more effective treatments, as they allow researchers to identify circuit manipulations that normalize pathological network activity. In this review we highlight the utility of all-optical approaches to generate new psychiatric disease models where the specific circuit abnormalities associated with disease symptomology can be assessed in vivo and in response to manipulations designed to normalize disease states. We then outline the principles underlying all-optical interrogations of neural circuits and discuss practical considerations for experimental design.
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Affiliation(s)
- Christopher K Lafferty
- Department of Psychology, McGill University, Montreal, QC, Canada; Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, QC, Canada
| | - Thomas D Christinck
- Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, QC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Jonathan P Britt
- Department of Psychology, McGill University, Montreal, QC, Canada; Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, QC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada.
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25
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Abreu N, Levitz J. Optogenetic Techniques for Manipulating and Sensing G Protein-Coupled Receptor Signaling. Methods Mol Biol 2021; 2173:21-51. [PMID: 32651908 DOI: 10.1007/978-1-0716-0755-8_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
G protein-coupled receptors (GPCRs) form the largest class of membrane receptors in the mammalian genome with nearly 800 human genes encoding for unique subtypes. Accordingly, GPCR signaling is implicated in nearly all physiological processes. However, GPCRs have been difficult to study due in part to the complexity of their function which can lead to a plethora of converging or diverging downstream effects over different time and length scales. Classic techniques such as pharmacological control, genetic knockout and biochemical assays often lack the precision required to probe the functions of specific GPCR subtypes. Here we describe the rapidly growing set of optogenetic tools, ranging from methods for optical control of the receptor itself to optical sensing and manipulation of downstream effectors. These tools permit the quantitative measurements of GPCRs and their downstream signaling with high specificity and spatiotemporal precision.
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Affiliation(s)
- Nohely Abreu
- Biochemistry, Cell and Molecular Biology Graduate Program, Weill Cornell Medicine, New York, NY, USA
| | - Joshua Levitz
- Biochemistry, Cell and Molecular Biology Graduate Program, Weill Cornell Medicine, New York, NY, USA.
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, USA.
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Thornquist SC, Pitsch MJ, Auth CS, Crickmore MA. Biochemical evidence accumulates across neurons to drive a network-level eruption. Mol Cell 2021; 81:675-690.e8. [PMID: 33453167 PMCID: PMC7924971 DOI: 10.1016/j.molcel.2020.12.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 11/05/2020] [Accepted: 12/15/2020] [Indexed: 11/19/2022]
Abstract
Neural network computations are usually assumed to emerge from patterns of fast electrical activity. Challenging this view, we show that a male fly's decision to persist in mating hinges on a biochemical computation that enables processing over minutes to hours. Each neuron in a recurrent network contains slightly different internal molecular estimates of mating progress. Protein kinase A (PKA) activity contrasts this internal measurement with input from the other neurons to represent accumulated evidence that the goal of the network has been achieved. When consensus is reached, PKA pushes the network toward a large-scale and synchronized burst of calcium influx that we call an eruption. Eruptions transform continuous deliberation within the network into an all-or-nothing output, after which the male will no longer sacrifice his life to continue mating. Here, biochemical activity, invisible to most large-scale recording techniques, is the key computational currency directing behavior and motivational state.
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Affiliation(s)
- Stephen C Thornquist
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Maximilian J Pitsch
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Charlotte S Auth
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Michael A Crickmore
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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27
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Bianco M, Balena A, Pisanello M, Pisano F, Sileo L, Spagnolo B, Montinaro C, Sabatini BL, Vittorio MD, Pisanello F. Comparative study of autofluorescence in flat and tapered optical fibers towards application in depth-resolved fluorescence lifetime photometry in brain tissue. BIOMEDICAL OPTICS EXPRESS 2021; 12:993-1010. [PMID: 33680555 PMCID: PMC7901336 DOI: 10.1364/boe.410244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/21/2020] [Accepted: 12/29/2020] [Indexed: 05/05/2023]
Abstract
As the scientific community seeks efficient optical neural interfaces with sub-cortical structures of the mouse brain, a wide set of technologies and methods is being developed to monitor cellular events through fluorescence signals generated by genetically encoded molecules. Among these technologies, tapered optical fibers (TFs) take advantage of the modal properties of narrowing waveguides to enable both depth-resolved and wide-volume light collection from scattering tissue, with minimized invasiveness with respect to standard flat fiber stubs (FFs). However, light guided in patch cords as well as in FFs and TFs can result in autofluorescence (AF) signal, which can act as a source of time-variable noise and limit their application to probe fluorescence lifetime in vivo. In this work, we compare the AF signal of FFs and TFs, highlighting the influence of the cladding composition on AF generation. We show that the autofluorescence signal generated in TFs has a peculiar coupling pattern with guided modes, and that far-field detection can be exploited to separate functional fluorescence from AF. On these bases, we provide evidence that TFs can be employed to implement depth-resolved fluorescence lifetime photometry, potentially enabling the extraction of a new set of information from deep brain regions, as time-correlating single photon counting starts to be applied in freely-moving animals to monitor the intracellular biochemical state of neurons.
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Affiliation(s)
- Marco Bianco
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Ingegneria dell’Innovazione, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Antonio Balena
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Ingegneria dell’Innovazione, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Marco Pisanello
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Filippo Pisano
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Leonardo Sileo
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Barbara Spagnolo
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Cinzia Montinaro
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Bernardo L. Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Massimo De Vittorio
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Ingegneria dell’Innovazione, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Ferruccio Pisanello
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
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Tejeda HA, Wang H, Flores RJ, Yarur HE. Dynorphin/Kappa-Opioid Receptor System Modulation of Cortical Circuitry. Handb Exp Pharmacol 2021; 271:223-253. [PMID: 33580392 DOI: 10.1007/164_2021_440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cortical circuits control a plethora of behaviors, from sensation to cognition. The cortex is enriched with neuropeptides and receptors that play a role in information processing, including opioid peptides and their cognate receptors. The dynorphin (DYN)/kappa-opioid receptor (KOR) system has been implicated in the processing of sensory and motivationally-charged emotional information and is highly expressed in cortical circuits. This is important as dysregulation of DYN/KOR signaling in limbic and cortical circuits has been implicated in promoting negative affect and cognitive deficits in various neuropsychiatric disorders. However, research investigating the role of this system in controlling cortical circuits and computations therein is limited. Here, we review the (1) basic anatomy of cortical circuits, (2) anatomical architecture of the cortical DYN/KOR system, (3) functional regulation of cortical synaptic transmission and microcircuit function by the DYN/KOR system, (4) regulation of behavior by the cortical DYN/KOR system, (5) implications for the DYN/KOR system for human health and disease, and (6) future directions and unanswered questions for the field. Further work elucidating the role of the DYN/KOR system in controlling cortical information processing and associated behaviors will be of importance to increasing our understanding of principles underlying neuropeptide modulation of cortical circuits, mechanisms underlying sensation and perception, motivated and emotional behavior, and cognition. Increased emphasis in this area of study will also aid in the identification of novel ways to target the DYN/KOR system to treat neuropsychiatric disorders.
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Affiliation(s)
- Hugo A Tejeda
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | - Huikun Wang
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Rodolfo J Flores
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Hector E Yarur
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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Lee SJ, Lodder B, Chen Y, Patriarchi T, Tian L, Sabatini BL. Cell-type-specific asynchronous modulation of PKA by dopamine in learning. Nature 2020; 590:451-456. [PMID: 33361810 PMCID: PMC7889726 DOI: 10.1038/s41586-020-03050-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 10/30/2020] [Indexed: 01/07/2023]
Abstract
Reinforcement learning models postulate that dopamine (DA) releasing neurons (DANs) encode information about action and action outcome and provide a teaching signal to striatal spiny projection neurons (SPNs) in the form of DA release1. DA is thought to guide learning via dynamic and differential modulation of protein kinase A (PKA) in each class of SPN2. However, the real-time relationship between DA and SPN PKA remains untested in behaving animals. Here, we monitor the activity of DANs, extracellular DA levels, and net PKA activity in SPNs in the nucleus accumbens in mice during learning. We find positive and negative modulation of DA that evolves across training and is both necessary and sufficient to explain concurrent fluctuations in SPN PKA activity. The modulations of PKA in SPNs that express type-1 and type-2 DA receptors are dichotomous such that they are selectively sensitive to increases and decreases in DA, respectively, which occur at different phases of learning. Thus, PKA-dependent pathways in each class of SPNs are asynchronously engaged by positive or negative DA signals during learning.
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Affiliation(s)
- Suk Joon Lee
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Bart Lodder
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Yao Chen
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, USA.,Department of Neuroscience, Washington University School of Medicine, St Louis, MO, USA
| | - Tommaso Patriarchi
- Department of Biochemistry and Molecular Medicine, University of California, Davis, CA, USA.,Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Lin Tian
- Department of Biochemistry and Molecular Medicine, University of California, Davis, CA, USA
| | - Bernardo L Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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30
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Liput DJ, Nguyen TA, Augustin SM, Lee JO, Vogel SS. A Guide to Fluorescence Lifetime Microscopy and Förster's Resonance Energy Transfer in Neuroscience. CURRENT PROTOCOLS IN NEUROSCIENCE 2020; 94:e108. [PMID: 33232577 PMCID: PMC8274369 DOI: 10.1002/cpns.108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fluorescence lifetime microscopy (FLIM) and Förster's resonance energy transfer (FRET) are advanced optical tools that neuroscientists can employ to interrogate the structure and function of complex biological systems in vitro and in vivo using light. In neurobiology they are primarily used to study protein-protein interactions, to study conformational changes in protein complexes, and to monitor genetically encoded FRET-based biosensors. These methods are ideally suited to optically monitor changes in neurons that are triggered optogenetically. Utilization of this technique by neuroscientists has been limited, since a broad understanding of FLIM and FRET requires familiarity with the interactions of light and matter on a quantum mechanical level, and because the ultra-fast instrumentation used to measure fluorescent lifetimes and resonance energy transfer are more at home in a physics lab than in a biology lab. In this overview, we aim to help neuroscientists overcome these obstacles and thus feel more comfortable with the FLIM-FRET method. Our goal is to aid researchers in the neuroscience community to achieve a better understanding of the fundamentals of FLIM-FRET and encourage them to fully leverage its powerful ability as a research tool. Published 2020. U.S. Government.
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Affiliation(s)
- Daniel J. Liput
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Tuan A. Nguyen
- Laboratory of Biophotonics and Quantum Biology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Shana M. Augustin
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Jeong Oen Lee
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Steven S. Vogel
- Laboratory of Biophotonics and Quantum Biology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
- Corresponding author:
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31
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Nielsen CDT, Dhasmana D, Floresta G, Wohland T, Cilibrizzi A. Illuminating the Path to Target GPCR Structures and Functions. Biochemistry 2020; 59:3783-3795. [PMID: 32956586 DOI: 10.1021/acs.biochem.0c00606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
G-Protein-coupled receptors (GPCRs) are ubiquitous within eukaryotes, responsible for a wide array of physiological and pathological processes. Indeed, the fact that they are the most drugged target in the human genome is indicative of their importance. Despite the clear interest in GPCRs, most information regarding their activity has been so far obtained by analyzing the response from a "bulk medium". As such, this Perspective summarizes some of the common methods for this indirect observation. Nonetheless, by inspecting approaches applying super-resolution imaging, we argue that imaging is perfectly situated to obtain more detailed structural and spatial information, assisting in the development of new GPCR-targeted drugs and clinical strategies. The benefits of direct optical visualization of GPCRs are analyzed in the context of potential future directions in the field.
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Affiliation(s)
- Christian D-T Nielsen
- Imperial College London, White City Campus, Molecular Sciences Research Hub, 80 Wood Lane, London W12 0BZ, U.K
| | - Divya Dhasmana
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Giuseppe Floresta
- Institute of Pharmaceutical Science, King's College London, London SE1 9NH, U.K
| | - Thorsten Wohland
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Agostino Cilibrizzi
- Institute of Pharmaceutical Science, King's College London, London SE1 9NH, U.K
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32
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Tian Y, Yang S, Gao S. Advances, Perspectives and Potential Engineering Strategies of Light-Gated Phosphodiesterases for Optogenetic Applications. Int J Mol Sci 2020; 21:E7544. [PMID: 33066112 PMCID: PMC7590022 DOI: 10.3390/ijms21207544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/24/2020] [Accepted: 10/05/2020] [Indexed: 12/25/2022] Open
Abstract
The second messengers, cyclic adenosine 3'-5'-monophosphate (cAMP) and cyclic guanosine 3'-5'-monophosphate (cGMP), play important roles in many animal cells by regulating intracellular signaling pathways and modulating cell physiology. Environmental cues like temperature, light, and chemical compounds can stimulate cell surface receptors and trigger the generation of second messengers and the following regulations. The spread of cAMP and cGMP is further shaped by cyclic nucleotide phosphodiesterases (PDEs) for orchestration of intracellular microdomain signaling. However, localized intracellular cAMP and cGMP signaling requires further investigation. Optogenetic manipulation of cAMP and cGMP offers new opportunities for spatio-temporally precise study of their signaling mechanism. Light-gated nucleotide cyclases are well developed and applied for cAMP/cGMP manipulation. Recently discovered rhodopsin phosphodiesterase genes from protists established a new and direct biological connection between light and PDEs. Light-regulated PDEs are under development, and of demand to complete the toolkit for cAMP/cGMP manipulation. In this review, we summarize the state of the art, pros and cons of artificial and natural light-regulated PDEs, and discuss potential new strategies of developing light-gated PDEs for optogenetic manipulation.
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Affiliation(s)
| | | | - Shiqiang Gao
- Department of Neurophysiology, Physiological Institute, University of Wuerzburg, 97070 Wuerzburg, Germany; (Y.T.); (S.Y.)
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33
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An ultrasensitive biosensor for high-resolution kinase activity imaging in awake mice. Nat Chem Biol 2020; 17:39-46. [PMID: 32989297 DOI: 10.1038/s41589-020-00660-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 08/21/2020] [Indexed: 12/20/2022]
Abstract
Protein kinases control nearly every facet of cellular function. These key signaling nodes integrate diverse pathway inputs to regulate complex physiological processes, and aberrant kinase signaling is linked to numerous pathologies. While fluorescent protein-based biosensors have revolutionized the study of kinase signaling by allowing direct, spatiotemporally precise kinase activity measurements in living cells, powerful new molecular tools capable of robustly tracking kinase activity dynamics across diverse experimental contexts are needed to fully dissect the role of kinase signaling in physiology and disease. Here, we report the development of an ultrasensitive, second-generation excitation-ratiometric protein kinase A (PKA) activity reporter (ExRai-AKAR2), obtained via high-throughput linker library screening, that enables sensitive and rapid monitoring of live-cell PKA activity across multiple fluorescence detection modalities, including plate reading, cell sorting and one- or two-photon imaging. Notably, in vivo visual cortex imaging in awake mice reveals highly dynamic neuronal PKA activity rapidly recruited by forced locomotion.
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34
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Koveal D, Díaz-García CM, Yellen G. Fluorescent Biosensors for Neuronal Metabolism and the Challenges of Quantitation. Curr Opin Neurobiol 2020; 63:111-121. [PMID: 32559637 PMCID: PMC7646541 DOI: 10.1016/j.conb.2020.02.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 01/08/2023]
Abstract
Over the past decade, genetically encoded fluorescent biosensors that report metabolic changes have become valuable tools for understanding brain metabolism. These sensors have been targeted to specific brain regions and cell types in different organisms to track multiple metabolic processes at single cell (and subcellular) resolution. Here, we review genetically encoded biosensors used to study metabolism in the brain. We particularly focus on the principles needed to use these sensors quantitatively while avoiding false inferences from variations in sensor fluorescence that arise from differences in expression level or environmental influences such as pH or temperature.
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Affiliation(s)
- Dorothy Koveal
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Gary Yellen
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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35
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Smith SJ, Hawrylycz M, Rossier J, Sümbül U. New light on cortical neuropeptides and synaptic network plasticity. Curr Opin Neurobiol 2020; 63:176-188. [PMID: 32679509 DOI: 10.1016/j.conb.2020.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 04/11/2020] [Accepted: 04/13/2020] [Indexed: 01/14/2023]
Abstract
Neuropeptides, members of a large and evolutionarily ancient family of proteinaceous cell-cell signaling molecules, are widely recognized as extremely potent regulators of brain function and behavior. At the cellular level, neuropeptides are known to act mainly via modulation of ion channel and synapse function, but functional impacts emerging at the level of complex cortical synaptic networks have resisted mechanistic analysis. New findings from single-cell RNA-seq transcriptomics now illuminate intricate patterns of cortical neuropeptide signaling gene expression and new tools now offer powerful molecular access to cortical neuropeptide signaling. Here we highlight some of these new findings and tools, focusing especially on prospects for experimental and theoretical exploration of peptidergic and synaptic networks interactions underlying cortical function and plasticity.
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Affiliation(s)
- Stephen J Smith
- Allen Institute for Brain Science, 615 Westlake Ave N, Seattle WA, USA.
| | - Michael Hawrylycz
- Allen Institute for Brain Science, 615 Westlake Ave N, Seattle WA, USA
| | - Jean Rossier
- Neuroscience Paris Seine, Sorbonne Université, Paris, France
| | - Uygar Sümbül
- Allen Institute for Brain Science, 615 Westlake Ave N, Seattle WA, USA
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36
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Xu X, Lemmens LJM, den Hamer A, Merkx M, Ottmann C, Brunsveld L. Modular bioengineered kinase sensors via scaffold protein-mediated split-luciferase complementation. Chem Sci 2020; 11:5532-5536. [PMID: 32874496 PMCID: PMC7446724 DOI: 10.1039/d0sc00074d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 05/11/2020] [Indexed: 01/07/2023] Open
Abstract
Phosphorylation is a key regulation event in cellular signaling. To sense the underlying kinase activity, we engineered modular and easy adaptable serine kinase sensors for the exemplary kinases PKA, PKB and CHK1.
Phosphorylation is a key regulation event in cellular signaling. Sensing the underlying kinase activity is of crucial importance for its fundamental understanding and for drug development. For this, modular kinase activity sensing concepts are urgently needed. We engineered modular serine kinase sensors based on complementation of split NanoBiT luciferase on protein assembly platforms generated from the scaffold protein 14-3-3. The bioengineered platforms are modular and easy adaptable as exemplary shown using novel sensors for the kinases PKA, PKB, and CHK1. Two designs were conceptualized, both relying on binding of defined mono- or bivalent kinase recognition motifs to the 14-3-3 platform upon phosphorylation, resulting in reconstitution of active split-luciferase. Especially the design based on double phosphorylation and bivalent 14-3-3 binding exhibits high efficiency for signal amplification (>1000-fold) and sensitivity to specific kinases, including in cellular lysates.
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Affiliation(s)
- Xiaolu Xu
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
| | - Lenne J M Lemmens
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
| | - Anniek den Hamer
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
| | - Maarten Merkx
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
| | - Christian Ottmann
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
| | - Luc Brunsveld
- Laboratory of Chemical Biology , Department of Biomedical Engineering , Institute for Complex Molecular Systems (ICMS) , Eindhoven University of Technology , Den Dolech 2 , 5612AZ , Eindhoven , the Netherlands .
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37
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O'Banion CP, Yasuda R. Fluorescent sensors for neuronal signaling. Curr Opin Neurobiol 2020; 63:31-41. [PMID: 32203701 DOI: 10.1016/j.conb.2020.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 01/30/2020] [Accepted: 02/13/2020] [Indexed: 12/14/2022]
Abstract
Dissecting neuronal structure and function in relation to behavior is an immense undertaking. Researchers require imaging tools to study neuronal activity and biochemical signaling in situ in order to study the roles of neuronal and biochemical activity in information processing. A large number of genetically encoded fluorescent biosensors have been reported in the literature over the past few years as there is a push to develop new technology in neuroscience. Here, we review the classes and characteristics of fluorescent biosensors and highlight some considerations that investigators should keep in mind when choosing their tool. In addition, we discuss recent advances in biosensor development.
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Affiliation(s)
| | - Ryohei Yasuda
- Max Planck Florida Institute for Neuroscience, United States.
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38
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Argyrousi EK, Heckman PRA, Prickaerts J. Role of cyclic nucleotides and their downstream signaling cascades in memory function: Being at the right time at the right spot. Neurosci Biobehav Rev 2020; 113:12-38. [PMID: 32044374 DOI: 10.1016/j.neubiorev.2020.02.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 01/23/2020] [Accepted: 02/03/2020] [Indexed: 01/23/2023]
Abstract
A plethora of studies indicate the important role of cAMP and cGMP cascades in neuronal plasticity and memory function. As a result, altered cyclic nucleotide signaling has been implicated in the pathophysiology of mnemonic dysfunction encountered in several diseases. In the present review we provide a wide overview of studies regarding the involvement of cyclic nucleotides, as well as their upstream and downstream molecules, in physiological and pathological mnemonic processes. Next, we discuss the regulation of the intracellular concentration of cyclic nucleotides via phosphodiesterases, the enzymes that degrade cAMP and/or cGMP, and via A-kinase-anchoring proteins that refine signal compartmentalization of cAMP signaling. We also provide an overview of the available data pointing to the existence of specific time windows in cyclic nucleotide signaling during neuroplasticity and memory formation and the significance to target these specific time phases for improving memory formation. Finally, we highlight the importance of emerging imaging tools like Förster resonance energy transfer imaging and optogenetics in detecting, measuring and manipulating the action of cyclic nucleotide signaling cascades.
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Affiliation(s)
- Elentina K Argyrousi
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, 6200 MD, the Netherlands
| | - Pim R A Heckman
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, 6200 MD, the Netherlands
| | - Jos Prickaerts
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, 6200 MD, the Netherlands.
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Schmitt DL, Mehta S, Zhang J. Illuminating the kinome: Visualizing real-time kinase activity in biological systems using genetically encoded fluorescent protein-based biosensors. Curr Opin Chem Biol 2020; 54:63-69. [PMID: 31911398 PMCID: PMC7131877 DOI: 10.1016/j.cbpa.2019.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/07/2019] [Accepted: 11/16/2019] [Indexed: 02/06/2023]
Abstract
Genetically encoded fluorescent protein-based kinase biosensors are a central tool for illumination of the kinome. The adaptability and versatility of biosensors have allowed for spatiotemporal observation of real-time kinase activity in living cells and organisms. In this review, we highlight various types of kinase biosensors, along with their burgeoning applications in complex biological systems. Specifically, we focus on kinase activity reporters used in neuronal systems and whole animal settings. Genetically encoded kinase biosensors are key for elucidation of the spatiotemporal regulation of protein kinases, with broader applications beyond the Petri dish.
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Affiliation(s)
- Danielle L Schmitt
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Jin Zhang
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA; Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA; Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
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40
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Thornquist SC, Langer K, Zhang SX, Rogulja D, Crickmore MA. CaMKII Measures the Passage of Time to Coordinate Behavior and Motivational State. Neuron 2020; 105:334-345.e9. [PMID: 31786014 PMCID: PMC7374950 DOI: 10.1016/j.neuron.2019.10.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 08/30/2019] [Accepted: 10/09/2019] [Indexed: 12/18/2022]
Abstract
Electrical events in neurons occur on the order of milliseconds, but the brain can process and reproduce intervals millions of times longer. We present what we believe to be the first neuronal mechanism for timing intervals longer than a few seconds. The activation and gradual relaxation of calcium-independent CaMKII measure a 6-min time window to coordinate two male-specific events during Drosophila mating: sperm transfer and a simultaneous decrease in motivation. We localize these functions to four neurons whose electrical activity is necessary only to report the conclusion of the decline in CaMKII's activity, not for the measurement of the interval. The computation of elapsed time is therefore largely invisible to standard methods of monitoring neuronal activity. Its broad conservation, ubiquitous expression, and tunable duration of activity suggest that CaMKII may time a wide variety of behavioral and cognitive processes.
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Affiliation(s)
- Stephen C Thornquist
- FM Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Kirill Langer
- FM Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen X Zhang
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Dragana Rogulja
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Michael A Crickmore
- FM Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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41
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Aso Y, Ray RP, Long X, Bushey D, Cichewicz K, Ngo TT, Sharp B, Christoforou C, Hu A, Lemire AL, Tillberg P, Hirsh J, Litwin-Kumar A, Rubin GM. Nitric oxide acts as a cotransmitter in a subset of dopaminergic neurons to diversify memory dynamics. eLife 2019; 8:49257. [PMID: 31724947 PMCID: PMC6948953 DOI: 10.7554/elife.49257] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/13/2019] [Indexed: 12/31/2022] Open
Abstract
Animals employ diverse learning rules and synaptic plasticity dynamics to record temporal and statistical information about the world. However, the molecular mechanisms underlying this diversity are poorly understood. The anatomically defined compartments of the insect mushroom body function as parallel units of associative learning, with different learning rates, memory decay dynamics and flexibility (Aso and Rubin, 2016). Here, we show that nitric oxide (NO) acts as a neurotransmitter in a subset of dopaminergic neurons in Drosophila. NO's effects develop more slowly than those of dopamine and depend on soluble guanylate cyclase in postsynaptic Kenyon cells. NO acts antagonistically to dopamine; it shortens memory retention and facilitates the rapid updating of memories. The interplay of NO and dopamine enables memories stored in local domains along Kenyon cell axons to be specialized for predicting the value of odors based only on recent events. Our results provide key mechanistic insights into how diverse memory dynamics are established in parallel memory systems.
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Affiliation(s)
- Yoshinori Aso
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Robert P Ray
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Xi Long
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Daniel Bushey
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Karol Cichewicz
- Department of Biology, University of Virginia, Charlottesville, United States
| | - Teri-Tb Ngo
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Brandi Sharp
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | | | - Amy Hu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Andrew L Lemire
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Paul Tillberg
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Jay Hirsh
- Department of Biology, University of Virginia, Charlottesville, United States
| | - Ashok Litwin-Kumar
- Department of Neuroscience, Columbia University, New York, United States
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
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42
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Smith SJ, Sümbül U, Graybuck LT, Collman F, Seshamani S, Gala R, Gliko O, Elabbady L, Miller JA, Bakken TE, Rossier J, Yao Z, Lein E, Zeng H, Tasic B, Hawrylycz M. Single-cell transcriptomic evidence for dense intracortical neuropeptide networks. eLife 2019; 8:47889. [PMID: 31710287 PMCID: PMC6881117 DOI: 10.7554/elife.47889] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 11/10/2019] [Indexed: 12/19/2022] Open
Abstract
Seeking new insights into the homeostasis, modulation and plasticity of cortical synaptic networks, we have analyzed results from a single-cell RNA-seq study of 22,439 mouse neocortical neurons. Our analysis exposes transcriptomic evidence for dozens of molecularly distinct neuropeptidergic modulatory networks that directly interconnect all cortical neurons. This evidence begins with a discovery that transcripts of one or more neuropeptide precursor (NPP) and one or more neuropeptide-selective G-protein-coupled receptor (NP-GPCR) genes are highly abundant in all, or very nearly all, cortical neurons. Individual neurons express diverse subsets of NP signaling genes from palettes encoding 18 NPPs and 29 NP-GPCRs. These 47 genes comprise 37 cognate NPP/NP-GPCR pairs, implying the likelihood of local neuropeptide signaling. Here, we use neuron-type-specific patterns of NP gene expression to offer specific, testable predictions regarding 37 peptidergic neuromodulatory networks that may play prominent roles in cortical homeostasis and plasticity.
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Affiliation(s)
| | - Uygar Sümbül
- Allen Institute for Brain Science, Seattle, United States
| | | | | | | | - Rohan Gala
- Allen Institute for Brain Science, Seattle, United States
| | - Olga Gliko
- Allen Institute for Brain Science, Seattle, United States
| | - Leila Elabbady
- Allen Institute for Brain Science, Seattle, United States
| | | | | | - Jean Rossier
- Neuroscience Paris Seine, Sorbonne Université, Paris, France
| | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, United States
| | - Ed Lein
- Allen Institute for Brain Science, Seattle, United States
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, United States
| | - Bosiljka Tasic
- Allen Institute for Brain Science, Seattle, United States
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43
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Lin W, Mehta S, Zhang J. Genetically encoded fluorescent biosensors illuminate kinase signaling in cancer. J Biol Chem 2019; 294:14814-14822. [PMID: 31434714 DOI: 10.1074/jbc.rev119.006177] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein kinase signaling networks stringently regulate cellular processes, such as proliferation, motility, and cell survival. These networks are also central to the evolution and progression of cancer. Accordingly, genetically encoded fluorescent biosensors capable of directly illuminating the spatiotemporal dynamics of kinase signaling in live cells are being increasingly used to investigate kinase signaling in cancer cells and tumor tissue sections. These biosensors enable visualization of biological processes and events directly in situ, preserving the native biological context and providing detailed insight into their localization and dynamics in cells. Herein, we first review common design strategies for kinase activity biosensors, including signaling targets, biosensor components, and fluorescent proteins involved. Subsequently, we discuss applications of biosensors to study the biology and management of cancer. These versatile molecular tools have been deployed to study oncogenic kinase signaling in living cells and image kinase activities in tumors or to decipher the mechanisms of anticancer drugs. We anticipate that the diversity and precision of genetically encoded biosensors will expand their use to further unravel the dysregulation of kinase signaling in cancer and the modes of actions of cancer-targeting drugs.
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Affiliation(s)
- Wei Lin
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0702
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0702
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0702
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44
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Lee SJ, Chen Y, Lodder B, Sabatini BL. Monitoring Behaviorally Induced Biochemical Changes Using Fluorescence Lifetime Photometry. Front Neurosci 2019; 13:766. [PMID: 31417343 PMCID: PMC6685078 DOI: 10.3389/fnins.2019.00766] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 07/09/2019] [Indexed: 02/06/2023] Open
Abstract
All cells respond to extracellular signals by altering their intracellular biochemical state. In neurons, such signaling regulates many aspects of cell and synapse biology and induces changes that are thought to be important for nervous system development, its adaptation in the face of a changing environment, and ongoing homeostatic maintenance. Although great advances have been made in developing novel fluorescent reporters of intracellular signaling as well as in methods of fluorescence detection for use in freely moving animals, these approaches have generally not been combined. Thus, we know relatively little about how the intracellular biochemical state of neurons, and other cell classes, is dynamically regulated during animals' behavior. Here we describe a single multi-mode fiber based fluorescence lifetime photometry system (FLiP) designed to monitor the state of fluorescence reporters of biochemical state in freely moving animals. We demonstrate the utility of FLiP by monitoring the lifetime of FLIM-AKAR, a genetically encoded fluorescent reporter of PKA phosphorylation, in populations of direct and indirect pathway striatal projection neurons in mice receiving food rewards. We find that the activity of PKA in each pathway is transiently regulated by reward acquisition, with PKA phosphorylation being enhanced and repressed in direct and indirect pathway neurons, respectively. This study demonstrates the power of FLiP to detect changes in biochemical state induced by naturalistic experiences in behaving animals.
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Affiliation(s)
- Suk Joon Lee
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
| | - Yao Chen
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Bart Lodder
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
- Master Program Neuroscience and Cognition, Graduate School of Life Sciences, Utrecht University and Department of Translational Neuroscience, Brain Center, University Medical Center, Utrecht, Netherlands
| | - Bernardo L. Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
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45
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Haynes EP, Rajendran M, Henning CK, Mishra A, Lyon AM, Tantama M. Quantifying Acute Fuel and Respiration Dependent pH Homeostasis in Live Cells Using the mCherryTYG Mutant as a Fluorescence Lifetime Sensor. Anal Chem 2019; 91:8466-8475. [PMID: 31247720 PMCID: PMC6623984 DOI: 10.1021/acs.analchem.9b01562] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Intracellular pH plays a key role in physiology, and its measurement in living specimens remains a crucial task in biology. Fluorescent protein-based pH sensors have gained widespread use, but there is limited spectral diversity for multicolor detection, and it remains a challenge to measure absolute pH values. Here we demonstrate that mCherryTYG is an excellent fluorescence lifetime pH sensor that significantly expands the modalities available for pH quantification in live cells. We first report the 1.09 Å X-ray crystal structure of mCherryTYG, exhibiting a fully matured chromophore. We next determine that it has an extraordinarily large dynamic range with a 2 ns lifetime change from pH 5.5 to 9.0. Critically, we find that the sensor maintains a p Ka of 6.8 independent of environment, whether as the purified protein in solution or expressed in live cells. Furthermore, the lifetime measurements are robustly independent of total fluorescence intensity and scatter. We demonstrate that mCherryTYG is a highly effective sensor using time-resolved fluorescence spectroscopy on live-cell suspensions, which has been previously overlooked as an easily accessible approach for quantifying intracellular pH. As a red fluorescent sensor, we also demonstrate that mCherryTYG is spectrally compatible with the ATeam sensor and EGFP for simultaneous dual-color measurements of intracellular pH, ATP, and extracellular pH. In a proof-of-concept, we quantify acute respiration-dependent pH homeostasis that exhibits a stoichiometric relationship with the ATP-generating capacity of the carbon fuel choice in E. coli. Broadly speaking, our work presents a previously unemployed methodology that will greatly facilitate continuous pH quantification.
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Affiliation(s)
- Emily P. Haynes
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | - Megha Rajendran
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute for Integrative Neuroscience, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | | | | | - Angeline M. Lyon
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Department of Biological Sciences, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | - Mathew Tantama
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute for Integrative Neuroscience, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
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46
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Jongbloets BC, Ma L, Mao T, Zhong H. Visualizing Protein Kinase A Activity In Head-fixed Behaving Mice Using In Vivo Two-photon Fluorescence Lifetime Imaging Microscopy. J Vis Exp 2019. [PMID: 31233029 DOI: 10.3791/59526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Neuromodulation exerts powerful control over brain function. Dysfunction of neuromodulatory systems results in neurological and psychiatric disorders. Despite their importance, technologies for tracking neuromodulatory events with cellular resolution are just beginning to emerge. Neuromodulators, such as dopamine, norepinephrine, acetylcholine, and serotonin, trigger intracellular signaling events via their respective G protein-coupled receptors to modulate neuronal excitability, synaptic communications, and other neuronal functions, thereby regulating information processing in the neuronal network. The above mentioned neuromodulators converge onto the cAMP/protein kinase A (PKA) pathway. Therefore, in vivo PKA imaging with single-cell resolution was developed as a readout for neuromodulatory events in a manner analogous to calcium imaging for neuronal electrical activities. Herein, a method is presented to visualize PKA activity at the level of individual neurons in the cortex of head-fixed behaving mice. To do so, an improved A-kinase activity reporter (AKAR), called tAKARα, is used, which is based on Förster resonance energy transfer (FRET). This genetically-encoded PKA sensor is introduced into the motor cortex via in utero electroporation (IUE) of DNA plasmids, or stereotaxic injection of adeno-associated virus (AAV). FRET changes are imaged using two-photon fluorescence lifetime imaging microscopy (2pFLIM), which offers advantages over ratiometric FRET measurements for quantifying FRET signal in light-scattering brain tissue. To study PKA activities during enforced locomotion, tAKARα is imaged through a chronic cranial window above the cortex of awake, head-fixed mice, which run or rest on a speed-controlled motorized treadmill. This imaging approach will be applicable to many other brain regions to study corresponding behavior-induced PKA activities and to other FLIM-based sensors for in vivo imaging.
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Affiliation(s)
| | - Lei Ma
- Vollum Institute, Oregon Health & Science University
| | - Tianyi Mao
- Vollum Institute, Oregon Health & Science University
| | - Haining Zhong
- Vollum Institute, Oregon Health & Science University;
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47
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Gowrishankar R, Bruchas MR. Defining circuit-specific roles for G protein-coupled receptors in aversive learning. Curr Opin Behav Sci 2019; 26:146-156. [PMID: 32855999 DOI: 10.1016/j.cobeha.2019.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The encoding of negative valence in response to noxious stimuli/experiences and in turn, the behavioral representation of negative affective states is essential for survival. Recent advances in neuroscience have determined multiple sites of neural plasticity and key circuits of connectivity across these regions in mediating aversive behavior. G protein-coupled receptors (GPCRs), owing to their neuromodulatory role, are especially important to refining our understanding of the molecular substrates involved in these circuits. In this review, we will focus on recent, contemporary findings that explore neural circuit-specific roles for neurotransmitter/peptide GPCRs and the importance of using novel approaches to illuminate the molecular mechanisms central to aversive learning.
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Affiliation(s)
- Raajaram Gowrishankar
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195
| | - Michael R Bruchas
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195.,Department of Pharmacology, Center for the Neurobiology of Addiction, University of Washington, Seattle, WA 98195.,Pain and Emotion, University of Washington, Seattle, WA 98195
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48
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Muntean BS, Zucca S, MacMullen CM, Dao MT, Johnston C, Iwamoto H, Blakely RD, Davis RL, Martemyanov KA. Interrogating the Spatiotemporal Landscape of Neuromodulatory GPCR Signaling by Real-Time Imaging of cAMP in Intact Neurons and Circuits. Cell Rep 2019; 22:255-268. [PMID: 29298426 DOI: 10.1016/j.celrep.2017.12.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/08/2017] [Accepted: 12/05/2017] [Indexed: 10/18/2022] Open
Abstract
Modulation of neuronal circuits is key to information processing in the brain. The majority of neuromodulators exert their effects by activating G-protein-coupled receptors (GPCRs) that control the production of second messengers directly impacting cellular physiology. How numerous GPCRs integrate neuromodulatory inputs while accommodating diversity of incoming signals is poorly understood. In this study, we develop an in vivo tool and analytical suite for analyzing GPCR responses by monitoring the dynamics of a key second messenger, cyclic AMP (cAMP), with excellent quantitative and spatiotemporal resolution in various neurons. Using this imaging approach in combination with CRISPR/Cas9 editing and optogenetics, we interrogate neuromodulatory mechanisms of defined populations of neurons in an intact mesolimbic reward circuit and describe how individual inputs generate discrete second-messenger signatures in a cell- and receptor-specific fashion. This offers a resource for studying native neuronal GPCR signaling in real time.
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Affiliation(s)
- Brian S Muntean
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Stefano Zucca
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Courtney M MacMullen
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Maria T Dao
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Caitlin Johnston
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Hideki Iwamoto
- Department of Biomedical Science and Brain Institute, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Randy D Blakely
- Department of Biomedical Science and Brain Institute, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Ronald L Davis
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458 USA.
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49
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Greenwald EC, Mehta S, Zhang J. Genetically Encoded Fluorescent Biosensors Illuminate the Spatiotemporal Regulation of Signaling Networks. Chem Rev 2018; 118:11707-11794. [PMID: 30550275 PMCID: PMC7462118 DOI: 10.1021/acs.chemrev.8b00333] [Citation(s) in RCA: 302] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cellular signaling networks are the foundation which determines the fate and function of cells as they respond to various cues and stimuli. The discovery of fluorescent proteins over 25 years ago enabled the development of a diverse array of genetically encodable fluorescent biosensors that are capable of measuring the spatiotemporal dynamics of signal transduction pathways in live cells. In an effort to encapsulate the breadth over which fluorescent biosensors have expanded, we endeavored to assemble a comprehensive list of published engineered biosensors, and we discuss many of the molecular designs utilized in their development. Then, we review how the high temporal and spatial resolution afforded by fluorescent biosensors has aided our understanding of the spatiotemporal regulation of signaling networks at the cellular and subcellular level. Finally, we highlight some emerging areas of research in both biosensor design and applications that are on the forefront of biosensor development.
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Affiliation(s)
- Eric C Greenwald
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Sohum Mehta
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Jin Zhang
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
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50
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Frank JA, Broichhagen J, Yushchenko DA, Trauner D, Schultz C, Hodson DJ. Optical tools for understanding the complexity of β-cell signalling and insulin release. Nat Rev Endocrinol 2018; 14:721-737. [PMID: 30356209 DOI: 10.1038/s41574-018-0105-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Following stimulation, pancreatic β-cells must orchestrate a plethora of signalling events to ensure the appropriate release of insulin and maintenance of normal glucose homeostasis. Failure at any point in this cascade leads to impaired insulin secretion, elevated blood levels of glucose and eventually type 2 diabetes mellitus. Likewise, β-cell replacement or regeneration strategies for the treatment of both type 1 and type 2 diabetes mellitus might fail if the correct cell signalling phenotype cannot be faithfully recreated. However, current understanding of β-cell function is complicated because of the highly dynamic nature of their intracellular and intercellular signalling as well as insulin release itself. β-Cells must precisely integrate multiple signals stemming from multiple cues, often with differing intensities, frequencies and cellular and subcellular localizations, before converging these signals onto insulin exocytosis. In this respect, optical approaches with high resolution in space and time are extremely useful for properly deciphering the complexity of β-cell signalling. An increased understanding of β-cell signalling might identify new mechanisms underlying insulin release, with relevance for future drug therapy and de novo stem cell engineering of functional islets.
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Affiliation(s)
- James A Frank
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Johannes Broichhagen
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Dmytro A Yushchenko
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Dirk Trauner
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemistry, New York University, New York, NY, USA
| | - Carsten Schultz
- European Molecular Biology Laboratory (EMBL), Cell Biology and Biophysics Unit, Heidelberg, Germany.
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA.
| | - David J Hodson
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK.
- Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK.
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