1
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Revealing the tissue-level complexity of endogenous glucagon-like peptide-1 receptor expression and signaling. Nat Commun 2023; 14:301. [PMID: 36653347 PMCID: PMC9849236 DOI: 10.1038/s41467-022-35716-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 12/21/2022] [Indexed: 01/19/2023] Open
Abstract
The glucagon-like peptide-1 receptor (GLP1R) is a class B G protein-coupled receptor (GPCR) involved in glucose homeostasis and food intake. GLP1R agonists (GLP1RA) are widely used in the treatment of diabetes and obesity, yet visualizing the endogenous localization, organization and dynamics of a GPCR has so far remained out of reach. In the present study, we generate mice harboring an enzyme self-label genome-edited into the endogenous Glp1r locus. We also rationally design and test various fluorescent dyes, spanning cyan to far-red wavelengths, for labeling performance in tissue. By combining these technologies, we show that endogenous GLP1R can be specifically and sensitively detected in primary tissue using multiple colors. Longitudinal analysis of GLP1R dynamics reveals heterogeneous recruitment of neighboring cell subpopulations into signaling and trafficking, with differences observed between GLP1RA classes and dual agonists. At the nanoscopic level, GLP1Rs are found to possess higher organization, undergoing GLP1RA-dependent membrane diffusion. Together, these results show the utility of enzyme self-labels for visualization and interrogation of endogenous proteins, and provide insight into the biology of a class B GPCR in primary cells and tissue.
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2
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Hickey DG, Davies WIL, Hughes S, Rodgers J, Thavanesan N, MacLaren RE, Hankins MW. Chimeric human opsins as optogenetic light sensitisers. J Exp Biol 2021; 224:270919. [PMID: 34151984 PMCID: PMC8325934 DOI: 10.1242/jeb.240580] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 06/08/2021] [Indexed: 12/03/2022]
Abstract
Human opsin-based photopigments have great potential as light-sensitisers, but their requirement for phototransduction cascade-specific second messenger proteins may restrict their functionality in non-native cell types. In this study, eight chimeric human opsins were generated consisting of a backbone of either a rhodopsin (RHO) or long-wavelength-sensitive (LWS) opsin and intracellular domains from Gq/11-coupled human melanopsin. Rhodopsin/melanopsin chimeric opsins coupled to both Gi and Gq/11 pathways. Greater substitution of the intracellular surface with corresponding melanopsin domains generally showed greater Gq/11 activity with a decrease in Gi activation. Unlike melanopsin, rhodopsin and rhodopsin/melanopsin chimeras were dependent upon exogenous chromophore to function. By contrast, wild-type LWS opsin and LWS opsin/melanopsin chimeras showed only weak Gi activation in response to light, whilst Gq/11 pathway activation was not detected. Immunocytochemistry (ICC) demonstrated that chimeric opsins with more intracellular domains of melanopsin were less likely to be trafficked to the plasma membrane. This study demonstrates the importance of Gα coupling efficiency to the speed of cellular responses and created human opsins with a unique combination of properties to expand the range of customised optogenetic biotools for basic research and translational therapies. Summary: Combining different domains of human visual opsins and melanopsin creates functionally unique chimeric opsins with potential optogenetic applications.
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Affiliation(s)
- Doron G Hickey
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,The Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia
| | - Wayne I L Davies
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,Umeå Centre for Molecular Medicine, Umeå University, Umeå, S-90187, Sweden.,School of Life Sciences, College of Science, Health and Engineering, La Trobe University, Melbourne, VIC 3086, Australia
| | - Steven Hughes
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, OX1 3QU, UK
| | - Jessica Rodgers
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, OX1 3QU, UK.,Division of Neuroscience and Experimental Psychology, University of Manchester, Manchester, M13 9PT, UK
| | | | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust and Oxford NIHR Biomedical Research Centre, Oxford, OX3 9DU,UK
| | - Mark W Hankins
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, OX1 3QU, UK.,Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, OX1 3QU, UK
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3
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Cross-Talk Between the Adenylyl Cyclase/cAMP Pathway and Ca 2+ Homeostasis. Rev Physiol Biochem Pharmacol 2021; 179:73-116. [PMID: 33398503 DOI: 10.1007/112_2020_55] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cyclic AMP and Ca2+ are the first second or intracellular messengers identified, unveiling the cellular mechanisms activated by a plethora of extracellular signals, including hormones. Cyclic AMP generation is catalyzed by adenylyl cyclases (ACs), which convert ATP into cAMP and pyrophosphate. By the way, Ca2+, as energy, can neither be created nor be destroyed; Ca2+ can only be transported, from one compartment to another, or chelated by a variety of Ca2+-binding molecules. The fine regulation of cytosolic concentrations of cAMP and free Ca2+ is crucial in cell function and there is an intimate cross-talk between both messengers to fine-tune the cellular responses. Cancer is a multifactorial disease resulting from a combination of genetic and environmental factors. Frequent cases of cAMP and/or Ca2+ homeostasis remodeling have been described in cancer cells. In those tumoral cells, cAMP and Ca2+ signaling plays a crucial role in the development of hallmarks of cancer, including enhanced proliferation and migration, invasion, apoptosis resistance, or angiogenesis. This review summarizes the cross-talk between the ACs/cAMP and Ca2+ intracellular pathways with special attention to the functional and reciprocal regulation between Orai1 and AC8 in normal and cancer cells.
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4
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Sánchez-Collado J, López JJ, Rosado JA. The Orai1-AC8 Interplay: How Breast Cancer Cells Escape from Orai1 Channel Inactivation. Cells 2021; 10:1308. [PMID: 34070268 PMCID: PMC8225208 DOI: 10.3390/cells10061308] [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] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/17/2021] [Accepted: 05/20/2021] [Indexed: 11/16/2022] Open
Abstract
The interplay between the Ca2+-sensitive adenylyl cyclase 8 (AC8) and Orai1 channels plays an important role both in the activation of the cAMP/PKA signaling and the modulation of Orai1-dependent Ca2+ signals. AC8 interacts with a N-terminal region that is exclusive to the Orai1 long variant, Orai1α. The interaction between both proteins allows the Ca2+ that enters the cell through Orai1α to activate the generation of cAMP by AC8. Subsequent PKA activation results in Orai1α inactivation by phosphorylation at serine-34, thus shaping Orai1-mediated cellular functions. In breast cancer cells, AC8 plays a relevant role supporting a variety of cancer hallmarks, including proliferation and migration. Breast cancer cells overexpress AC8, which shifts the AC8-Orai1 stoichiometry in favor of the former and leads to the impairment of PKA-dependent Orai1α inactivation. This mechanism contributes to the enhanced SOCE observed in triple-negative breast cancer cells. This review summarizes the functional interaction between AC8 and Orai1α in normal and breast cancer cells and its relevance for different cancer features.
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Affiliation(s)
| | - José J. López
- Cellular Physiology Research Group, Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, 10003 Caceres, Spain;
| | - Juan A. Rosado
- Cellular Physiology Research Group, Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, 10003 Caceres, Spain;
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5
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Mehta S, Zhang J. Biochemical Activity Architectures Visualized-Using Genetically Encoded Fluorescent Biosensors to Map the Spatial Boundaries of Signaling Compartments. Acc Chem Res 2021; 54:2409-2420. [PMID: 33949851 DOI: 10.1021/acs.accounts.1c00056] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
All biological processes arise through the coordinated actions of biochemical pathways. How such functional diversity is achieved by a finite cast of molecular players remains a central mystery in biology. Spatial compartmentation-the idea that biochemical activities are organized around discrete spatial domains within cells-was first proposed nearly 40 years ago and has become firmly rooted in our understanding of how biochemical pathways are regulated to ensure specificity. However, directly interrogating spatial compartmentation and its mechanistic origins has only really become possible in the last 20 or so years, following technological advances such as the development of genetically encoded fluorescent biosensors. These powerful molecular tools permit a direct, real-time visualization of dynamic biochemical processes in native biological contexts, and they are essential for probing the spatial regulation of biochemical activities. In this Account, we review our lab's efforts in developing and using biosensors to map the spatial compartmentation of intracellular signaling pathways and illuminate key mechanisms that establish the boundaries of an intricate biochemical activity architecture. We first discuss the role of regulatory fences, wherein the dynamic activation and deactivation of diffusible messengers produce diverse signaling compartments. For example, we used biosensors for the Ca2+ effector calmodulin and its downstream target calcineurin to reveal a spatial gradient of calmodulin that controls the temporal dynamics of calcineurin signaling. Our studies using cyclic adenosine monophosphate (cAMP) biosensors have similarly elucidated fenced cAMP domains generated by competing production and degradation pathways, ranging in size from cell-spanning gradients to nanoscale hotspots. Second, we describe the role played by intracellular membranes in creating unique signaling platforms with distinctive pathway regulation, as revealed through studies using subcellularly targeted fluorescent biosensors. Using biosensors to visualize subcellular extracellular response kinase (ERK) pathway activity, for example, led us to discover a local signaling circuit that mediates distinct plasma membrane ERK dynamics versus global ERK signaling. Similarly, our work developing biosensors to monitor the subcellular mechanistic target of rapamycin complex 1 (mTORC1) signaling allowed us to not only clarify the presence of mTORC1 activity in the nucleus but also identify a novel mechanism governing the activation of mTORC1 in this location. Finally, we detail how molecular assemblies enable the precise spatial tuning of biochemical activity, through investigations enabled by cutting-edge advances in biosensor design. We recently identified liquid-liquid phase separation as a major factor in cAMP compartmentation aided by a new strategy for targeting biosensors to endogenously expressed proteins via genome editing, for instance, and have also been able to directly visualize nanometer-scale protein kinase signalosomes using an entirely new class of biosensors specifically developed for the dynamic super-resolution imaging of live-cell biochemical activities. Our work provides key insights into the molecular logic of spatially regulated signaling and lays the foundation for a broader exploration of biochemical activity architectures across multiple spatial scales.
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Affiliation(s)
- Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Jin Zhang
- Departments of Pharmacology, Bioengineering, and Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
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6
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Kim N, Shin S, Bae SW. cAMP Biosensors Based on Genetically Encoded Fluorescent/Luminescent Proteins. BIOSENSORS-BASEL 2021; 11:bios11020039. [PMID: 33572585 PMCID: PMC7911721 DOI: 10.3390/bios11020039] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 01/22/2021] [Accepted: 01/27/2021] [Indexed: 02/06/2023]
Abstract
Cyclic adenosine monophosphate (cAMP) plays a key role in signal transduction pathways as a second messenger. Studies on the cAMP dynamics provided useful scientific insights for drug development and treatment of cAMP-related diseases such as some cancers and prefrontal cortex disorders. For example, modulation of cAMP-mediated intracellular signaling pathways by anti-tumor drugs could reduce tumor growth. However, most early stage tools used for measuring the cAMP level in living organisms require cell disruption, which is not appropriate for live cell imaging or animal imaging. Thus, in the last decades, tools were developed for real-time monitoring of cAMP distribution or signaling dynamics in a non-invasive manner. Genetically-encoded sensors based on fluorescent proteins and luciferases could be powerful tools to overcome these drawbacks. In this review, we discuss the recent genetically-encoded cAMP sensors advances, based on single fluorescent protein (FP), Föster resonance energy transfer (FRET), single luciferase, and bioluminescence resonance energy transfer (BRET) for real-time non-invasive imaging.
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Affiliation(s)
- Namdoo Kim
- Department of Chemistry, Kongju National University, Gongju 32588, Korea;
| | - Seunghan Shin
- Green Chemistry & Materials Group, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea;
| | - Se Won Bae
- Green Chemistry & Materials Group, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea;
- Department of Chemistry and Cosmetics, Jeju National University, Jeju 63243, Korea
- Correspondence: ; Tel.: +82-64-754-3543
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7
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Tenner B, Getz M, Ross B, Ohadi D, Bohrer CH, Greenwald E, Mehta S, Xiao J, Rangamani P, Zhang J. Spatially compartmentalized phase regulation of a Ca 2+-cAMP-PKA oscillatory circuit. eLife 2020; 9:e55013. [PMID: 33201801 PMCID: PMC7671691 DOI: 10.7554/elife.55013] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 10/07/2020] [Indexed: 01/31/2023] Open
Abstract
Signaling networks are spatiotemporally organized to sense diverse inputs, process information, and carry out specific cellular tasks. In β cells, Ca2+, cyclic adenosine monophosphate (cAMP), and Protein Kinase A (PKA) exist in an oscillatory circuit characterized by a high degree of feedback. Here, we describe a mode of regulation within this circuit involving a spatial dependence of the relative phase between cAMP, PKA, and Ca2+. We show that in mouse MIN6 β cells, nanodomain clustering of Ca2+-sensitive adenylyl cyclases (ACs) drives oscillations of local cAMP levels to be precisely in-phase with Ca2+ oscillations, whereas Ca2+-sensitive phosphodiesterases maintain out-of-phase oscillations outside of the nanodomain. Disruption of this precise phase relationship perturbs Ca2+ oscillations, suggesting the relative phase within an oscillatory circuit can encode specific functional information. This work unveils a novel mechanism of cAMP compartmentation utilized for localized tuning of an oscillatory circuit and has broad implications for the spatiotemporal regulation of signaling networks.
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Affiliation(s)
- Brian Tenner
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins University School of MedicineBaltimoreUnited States
- Department of Pharmacology, University of California, San DiegoLa JollaUnited States
| | - Michael Getz
- Chemical Engineering Graduate Program, University of California, San DiegoLa JollaUnited States
| | - Brian Ross
- Department of Pharmacology, University of California, San DiegoLa JollaUnited States
| | - Donya Ohadi
- Department of Mechanical and Aerospace Engineering, University of California, San DiegoLa JollaUnited States
| | - Christopher H Bohrer
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Eric Greenwald
- Department of Pharmacology, University of California, San DiegoLa JollaUnited States
| | - Sohum Mehta
- Department of Pharmacology, University of California, San DiegoLa JollaUnited States
| | - Jie Xiao
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Padmini Rangamani
- Chemical Engineering Graduate Program, University of California, San DiegoLa JollaUnited States
- Department of Mechanical and Aerospace Engineering, University of California, San DiegoLa JollaUnited States
| | - Jin Zhang
- Department of Pharmacology, University of California, San DiegoLa JollaUnited States
- Department of Chemistry and Biochemistry, University of California, San DiegoLa JollaUnited States
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8
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Ast J, Arvaniti A, Fine NHF, Nasteska D, Ashford FB, Stamataki Z, Koszegi Z, Bacon A, Jones BJ, Lucey MA, Sasaki S, Brierley DI, Hastoy B, Tomas A, D'Agostino G, Reimann F, Lynn FC, Reissaus CA, Linnemann AK, D'Este E, Calebiro D, Trapp S, Johnsson K, Podewin T, Broichhagen J, Hodson DJ. Super-resolution microscopy compatible fluorescent probes reveal endogenous glucagon-like peptide-1 receptor distribution and dynamics. Nat Commun 2020; 11:467. [PMID: 31980626 PMCID: PMC6981144 DOI: 10.1038/s41467-020-14309-w] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 12/27/2019] [Indexed: 12/25/2022] Open
Abstract
The glucagon-like peptide-1 receptor (GLP1R) is a class B G protein-coupled receptor (GPCR) involved in metabolism. Presently, its visualization is limited to genetic manipulation, antibody detection or the use of probes that stimulate receptor activation. Herein, we present LUXendin645, a far-red fluorescent GLP1R antagonistic peptide label. LUXendin645 produces intense and specific membrane labeling throughout live and fixed tissue. GLP1R signaling can additionally be evoked when the receptor is allosterically modulated in the presence of LUXendin645. Using LUXendin645 and LUXendin651, we describe islet, brain and hESC-derived β-like cell GLP1R expression patterns, reveal higher-order GLP1R organization including membrane nanodomains, and track single receptor subpopulations. We furthermore show that the LUXendin backbone can be optimized for intravital two-photon imaging by installing a red fluorophore. Thus, our super-resolution compatible labeling probes allow visualization of endogenous GLP1R, and provide insight into class B GPCR distribution and dynamics both in vitro and in vivo. Glucagon-like peptide-1 receptor is an important regulator of appetite and glucose homeostasis. Here the authors describe super-resolution microscopy and in vivo imaging compatible fluorescent probes, which reveal endogenous glucagon-like peptide-1 receptor distribution and dynamics in islets and brain.
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Affiliation(s)
- Julia Ast
- 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
| | - Anastasia Arvaniti
- 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
| | - Nicholas H F Fine
- 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
| | - Daniela Nasteska
- 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
| | - Fiona B Ashford
- 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
| | - Zania Stamataki
- Centre for Liver Research, College of Medical and Dental Sciences, Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - Zsombor Koszegi
- 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
| | - Andrea Bacon
- Genome Editing Facility, Technology Hub, University of Birmingham, Birmingham, UK
| | - Ben J Jones
- Division of Diabetes, Endocrinology and Metabolism, Section of Investigative Medicine, Imperial College London, London, UK
| | - Maria A Lucey
- Division of Diabetes, Endocrinology and Metabolism, Section of Investigative Medicine, Imperial College London, London, UK
| | - Shugo Sasaki
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada; Department of Surgery, University of British Columbia, Vancouver, BC, Canada
| | - Daniel I Brierley
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Benoit Hastoy
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Oxford, UK
| | - Alejandra Tomas
- Division of Diabetes, Endocrinology and Metabolism, Section of Cell Biology and Functional Genomics, Imperial College London, London, UK
| | - Giuseppe D'Agostino
- Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, UK
| | - Frank Reimann
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Francis C Lynn
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada; Department of Surgery, University of British Columbia, Vancouver, BC, Canada
| | | | - Amelia K Linnemann
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Elisa D'Este
- Optical Microscopy Facility, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Davide Calebiro
- 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
| | - Stefan Trapp
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Kai Johnsson
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Tom Podewin
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.
| | - Johannes Broichhagen
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.
| | - 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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9
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Reuschlein AK, Jakobsen E, Mertz C, Bak LK. Aspects of astrocytic cAMP signaling with an emphasis on the putative power of compartmentalized signals in health and disease. Glia 2019; 67:1625-1636. [PMID: 31033018 DOI: 10.1002/glia.23622] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/29/2019] [Accepted: 03/29/2019] [Indexed: 12/17/2022]
Abstract
This review discusses aspects of known and putative compartmentalized 3',5'-cyclic adenosine monophosphate (cAMP) signaling in astrocytes, a cell type that has turned out to be a key player in brain physiology and pathology. cAMP has attracted less attention than Ca2+ in recent years, but could turn out to rival Ca2+ in its potential to drive cellular functions and responses to intra- and extracellular cues. Further, Ca2+ and cAMP are known to engage in extensive crosstalk and cAMP signals often take place within subcellular compartments revolving around multi-protein signaling complexes; however, we know surprisingly little about this in astrocytes. Here, we review aspects of astrocytic cAMP signaling, provide arguments for an increased interest in this subject, suggest possible future research directions within the field, and discuss putative drug targets.
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Affiliation(s)
- Ann-Kathrin Reuschlein
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emil Jakobsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christoffer Mertz
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lasse K Bak
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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10
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Optical approaches for single-cell and subcellular analysis of GPCR-G protein signaling. Anal Bioanal Chem 2019; 411:4481-4508. [PMID: 30927013 DOI: 10.1007/s00216-019-01774-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 03/05/2019] [Accepted: 03/08/2019] [Indexed: 01/05/2023]
Abstract
G protein-coupled receptors (GPCRs), G proteins, and their signaling associates are major signal transducers that control the majority of cellular signaling and regulate key biological functions including immune, neurological, cardiovascular, and metabolic processes. These pathways are targeted by over one-third of drugs on the market; however, the current understanding of their function is limited and primarily derived from cell-destructive approaches providing an ensemble of static, multi-cell information about the status and composition of molecules. Spatiotemporal behavior of molecules involved is crucial to understanding in vivo cell behaviors both in health and disease, and the advent of genetically encoded fluorescence proteins and small fluorophore-based biosensors has facilitated the mapping of dynamic signaling in cells with subcellular acuity. Since we and others have developed optogenetic methods to regulate GPCR-G protein signaling in single cells and subcellular regions using dedicated wavelengths, the desire to develop and adopt optogenetically amenable assays to measure signaling has motivated us to take a broader look at the available optical tools and approaches compatible with measuring single-cell and subcellular GPCR-G protein signaling. Here we review such key optical approaches enabling the examination of GPCR, G protein, secondary messenger, and downstream molecules such as kinase and lipid signaling in living cells. The methods reviewed employ both fluorescence and bioluminescence detection. We not only further elaborate the underlying principles of these sensors but also discuss the experimental criteria and limitations to be considered during their use in single-cell and subcellular signal mapping.
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11
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Dumbacher M, Van Dooren T, Princen K, De Witte K, Farinelli M, Lievens S, Tavernier J, Dehaen W, Wera S, Winderickx J, Allasia S, Kilonda A, Spieser S, Marchand A, Chaltin P, Hoogenraad CC, Griffioen G. Modifying Rap1-signalling by targeting Pde6δ is neuroprotective in models of Alzheimer's disease. Mol Neurodegener 2018; 13:50. [PMID: 30257685 PMCID: PMC6158915 DOI: 10.1186/s13024-018-0283-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 09/13/2018] [Indexed: 01/06/2023] Open
Abstract
Background Neuronal Ca2+ dyshomeostasis and hyperactivity play a central role in Alzheimer’s disease pathology and progression. Amyloid-beta together with non-genetic risk-factors of Alzheimer’s disease contributes to increased Ca2+ influx and aberrant neuronal activity, which accelerates neurodegeneration in a feed-forward fashion. As such, identifying new targets and drugs to modulate excessive Ca2+ signalling and neuronal hyperactivity, without overly suppressing them, has promising therapeutic potential. Methods Here we show, using biochemical, electrophysiological, imaging, and behavioural tools, that pharmacological modulation of Rap1 signalling by inhibiting its interaction with Pde6δ normalises disease associated Ca2+ aberrations and neuronal activity, conferring neuroprotection in models of Alzheimer’s disease. Results The newly identified inhibitors of the Rap1-Pde6δ interaction counteract AD phenotypes, by reconfiguring Rap1 signalling underlying synaptic efficacy, Ca2+ influx, and neuronal repolarisation, without adverse effects in-cellulo or in-vivo. Thus, modulation of Rap1 by Pde6δ accommodates key mechanisms underlying neuronal activity, and therefore represents a promising new drug target for early or late intervention in neurodegenerative disorders. Conclusion Targeting the Pde6δ-Rap1 interaction has promising therapeutic potential for disorders characterised by neuronal hyperactivity, such as Alzheimer’s disease. Electronic supplementary material The online version of this article (10.1186/s13024-018-0283-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michael Dumbacher
- reMYND NV, Gaston Geenslaan 1, Leuven-Heverlee, 3001, Belgium.,Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584CH, Utrecht, The Netherlands
| | - Tom Van Dooren
- reMYND NV, Gaston Geenslaan 1, Leuven-Heverlee, 3001, Belgium
| | - Katrien Princen
- reMYND NV, Gaston Geenslaan 1, Leuven-Heverlee, 3001, Belgium
| | - Koen De Witte
- reMYND NV, Gaston Geenslaan 1, Leuven-Heverlee, 3001, Belgium
| | - Mélissa Farinelli
- E-Phy-Science, IPMC, 660 route des Lucioles, 06560, Sophia Antipolis, France
| | - Sam Lievens
- Orionis Biosciences, Technologiepark 12B, Zwijnaarde-Ghent, 9052, Belgium.,Cytokine Receptor Lab, Flanders Institute of Biotechnology, Medical Biotechnology Center, Faculty of Medicine and Health Sciences, Ghent University, Albert Baertsoenkaai 3, 9000, Ghent, Belgium
| | - Jan Tavernier
- Cytokine Receptor Lab, Flanders Institute of Biotechnology, Medical Biotechnology Center, Faculty of Medicine and Health Sciences, Ghent University, Albert Baertsoenkaai 3, 9000, Ghent, Belgium
| | - Wim Dehaen
- Department of Chemistry, KU Leuven, Celestijnenlaan 200f - box 2404, Leuven-Heverlee, 3001, Belgium
| | - Stefaan Wera
- ViroVet NV, Ambachtenlaan 1, Leuven-Heverlee, 3001, Belgium
| | - Joris Winderickx
- Department of Biology, Functional Biology, KU Leuven, Kasteelpark Arenberg 31 box 2433, Leuven-Heverlee, 3001, Belgium
| | - Sara Allasia
- Cistim Leuven vzw, Gaston Geenslaan 2, Leuven-Heverlee, 3001, Belgium
| | - Amuri Kilonda
- Cistim Leuven vzw, Gaston Geenslaan 2, Leuven-Heverlee, 3001, Belgium
| | - Stéphane Spieser
- Cistim Leuven vzw, Gaston Geenslaan 2, Leuven-Heverlee, 3001, Belgium
| | - Arnaud Marchand
- Cistim Leuven vzw, Gaston Geenslaan 2, Leuven-Heverlee, 3001, Belgium
| | - Patrick Chaltin
- Cistim Leuven vzw, Gaston Geenslaan 2, Leuven-Heverlee, 3001, Belgium.,Center for Drug Design and Development (CD3), KU Leuven, Waaistraat 6, 3000, Leuven, Belgium
| | - Casper C Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584CH, Utrecht, The Netherlands
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12
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Hu E, Du H, Zhu X, Wang L, Shang S, Wu X, Lu H, Lu X. Beta-hydroxybutyrate Promotes the Expression of BDNF in Hippocampal Neurons under Adequate Glucose Supply. Neuroscience 2018; 386:315-325. [PMID: 29966721 DOI: 10.1016/j.neuroscience.2018.06.036] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 06/17/2018] [Accepted: 06/21/2018] [Indexed: 01/09/2023]
Abstract
Neurobiological evidence suggests that the ketone metabolite β-hydroxybutyrate (BHBA) exerts many neuroprotective functions for the brain. The previous study revealed that BHBA could promote the expression of brain-derived neurotrophic factor (BDNF) at glucose inadequate condition. Here we demonstrated that BHBA administration induced the expression of BDNF in the hippocampus of mice fed with normal diet. In vitro experiment results also showed that 0.02-2 mM BHBA significantly increased BDNF expression in both the primary hippocampal neurons and the hippocampus neuron cell line HT22 under adequate glucose supply. Bdnf transcription induced by BHBA stimulus was mediated through the cAMP/PKA-triggered phosphorylation of CREB (S133) and the subsequent up-regulation of histone H3 Lysine 27 acetylation (H3K27ac) binding at Bdnf promoters I, II, IV, and VI. Moreover, BHBA stimulus induced a decrease in tri-methylation of H3K27 (H3K27me3) binding at the Bdnf promoters II and VI and the elevation of H3K27me3-specific demethylase JMJD3, which also contributed to the activation of Bdnf transcription. These results demonstrated that BHBA within the physiological range could promote BDNF expression in neurons via a novel signaling function. Moreover, BHBA might possess more broad epigenetic regulatory activities, which affected both the acetylation and demethylation of H3K27. Our findings reinforce the beneficial effect of BHBA on the central nervous system (CNS) and suggest that BHBA administration with no need for energy restriction might also be a promising intervention to improve the neuronal activity and ameliorate the degeneration of CNS.
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Affiliation(s)
- Erling Hu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Huan Du
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Xinliang Zhu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Leilei Wang
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Sen Shang
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Xingjuan Wu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Haixia Lu
- Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, Institute of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Centre, Xi'an 710061, Shaanxi, PR China.
| | - Xiaoyun Lu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China.
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13
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Buenaventura T, Kanda N, Douzenis PC, Jones B, Bloom SR, Chabosseau P, Corrêa IR, Bosco D, Piemonti L, Marchetti P, Johnson PR, Shapiro AMJ, Rutter GA, Tomas A. A Targeted RNAi Screen Identifies Endocytic Trafficking Factors That Control GLP-1 Receptor Signaling in Pancreatic β-Cells. Diabetes 2018; 67:385-399. [PMID: 29284659 DOI: 10.2337/db17-0639] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 12/19/2017] [Indexed: 11/13/2022]
Abstract
The glucagon-like peptide 1 (GLP-1) receptor (GLP-1R) is a key target for type 2 diabetes (T2D) treatment. Because endocytic trafficking of agonist-bound receptors is one of the most important routes for regulation of receptor signaling, a better understanding of this process may facilitate the development of new T2D therapeutic strategies. Here, we screened 29 proteins with known functions in G protein-coupled receptor trafficking for their role in GLP-1R potentiation of insulin secretion in pancreatic β-cells. We identify five (clathrin, dynamin1, AP2, sorting nexins [SNX] SNX27, and SNX1) that increase and four (huntingtin-interacting protein 1 [HIP1], HIP14, GASP-1, and Nedd4) that decrease insulin secretion from murine insulinoma MIN6B1 cells in response to the GLP-1 analog exendin-4. The roles of HIP1 and the endosomal SNX1 and SNX27 were further characterized in mouse and human β-cell lines and human islets. While HIP1 was required for the coupling of cell surface GLP-1R activation with clathrin-dependent endocytosis, the SNXs were found to control the balance between GLP-1R plasma membrane recycling and lysosomal degradation and, in doing so, determine the overall β-cell incretin responses. We thus identify key modulators of GLP-1R trafficking and signaling that might provide novel targets to enhance insulin secretion in T2D.
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Affiliation(s)
- Teresa Buenaventura
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K
| | - Nisha Kanda
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K
| | - Phoebe C Douzenis
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K
| | - Ben Jones
- Section of Investigative Medicine, Imperial College London, London, U.K
| | - Stephen R Bloom
- Section of Investigative Medicine, Imperial College London, London, U.K
| | - Pauline Chabosseau
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K
| | | | - Domenico Bosco
- Department of Surgery, University of Geneva, Geneva, Switzerland
| | - Lorenzo Piemonti
- Diabetes Research Institute, San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Piero Marchetti
- Department of Clinical and Experimental Medicine, Islet Cell Laboratory, University of Pisa, Pisa, Italy
| | - Paul R Johnson
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, U.K
| | - A M James Shapiro
- Clinical Islet Laboratory and Clinical Islet Transplant Program, University of Alberta, Edmonton, Alberta, Canada
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K
| | - Alejandra Tomas
- Section of Cell Biology and Functional Genomics and Pancreatic Islet Biology and Diabetes Consortium, Imperial College London, London, U.K.
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14
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Podewin T, Ast J, Broichhagen J, Fine NHF, Nasteska D, Leippe P, Gailer M, Buenaventura T, Kanda N, Jones BJ, M’Kadmi C, Baneres JL, Marie J, Tomas A, Trauner D, Hoffmann-Röder A, Hodson DJ. Conditional and Reversible Activation of Class A and B G Protein-Coupled Receptors Using Tethered Pharmacology. ACS CENTRAL SCIENCE 2018; 4:166-179. [PMID: 29532016 PMCID: PMC5832994 DOI: 10.1021/acscentsci.7b00237] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Indexed: 05/21/2023]
Abstract
Understanding the activation and internalization of G protein-coupled receptors (GPCRs) using conditional approaches is paramount to developing new therapeutic strategies. Here, we describe the design, synthesis, and testing of ExONatide, a benzylguanine-linked peptide agonist of the glucagon-like peptide-1 receptor (GLP-1R), a class B GPCR required for maintenance of glucose levels in humans. ExONatide covalently binds to SNAP-tagged GLP-1R-expressing cells, leading to prolonged cAMP generation, Ca2+ rises, and intracellular retention of the receptor. These effects were readily switched OFF following cleavage of the introduced disulfide bridge using the cell-permeable reducing agent beta-mercaptoethanol (BME). A similar approach could be extended to a class A GPCR using GhrelON, a benzylguanine-linked peptide agonist of the growth hormone secretagogue receptor 1a (GHS-R1a), which is involved in food intake and growth. Thus, ExONatide and GhrelON allow SNAP-tag-directed activation of class A and B GPCRs involved in gut hormone signaling in a reversible manner. This tactic, termed reductively cleavable agONist (RECON), may be useful for understanding GLP-1R and GHS-R1a function both in vitro and in vivo, with applicability across GPCRs.
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Affiliation(s)
- Tom Podewin
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
| | - Julia Ast
- Institute
of Metabolism and Systems Research (IMSR), University of Birmingham, B15 2TT, Birmingham, United Kingdom
- Centre
for Endocrinology, Diabetes and Metabolism, Birmingham
Health Partners, Birmingham, B15 2TH, United Kingdom, and COMPARE University of Birmingham and University of Nottingham
Midlands
| | - Johannes Broichhagen
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
| | - Nicholas H. F. Fine
- Institute
of Metabolism and Systems Research (IMSR), University of Birmingham, B15 2TT, Birmingham, United Kingdom
- Centre
for Endocrinology, Diabetes and Metabolism, Birmingham
Health Partners, Birmingham, B15 2TH, United Kingdom, and COMPARE University of Birmingham and University of Nottingham
Midlands
| | - Daniela Nasteska
- Institute
of Metabolism and Systems Research (IMSR), University of Birmingham, B15 2TT, Birmingham, United Kingdom
- Centre
for Endocrinology, Diabetes and Metabolism, Birmingham
Health Partners, Birmingham, B15 2TH, United Kingdom, and COMPARE University of Birmingham and University of Nottingham
Midlands
| | - Philipp Leippe
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
| | - Manuel Gailer
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
| | - Teresa Buenaventura
- Section
of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, London, W12 0NN, United Kingdom
| | - Nisha Kanda
- Section
of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, London, W12 0NN, United Kingdom
| | - Ben J. Jones
- Section
of Investigative Medicine, Division of Diabetes, Endocrinology and
Metabolism, Imperial College London, London, W12 0NN, United Kingdom
| | - Celine M’Kadmi
- Institut des Biomolécules
Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM,
Faculté de Pharmacie, 15 Avenue
Charles Flahault, BP 14491, 34093 Montpellier Cedex 05, France
| | - Jean-Louis Baneres
- Institut des Biomolécules
Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM,
Faculté de Pharmacie, 15 Avenue
Charles Flahault, BP 14491, 34093 Montpellier Cedex 05, France
| | - Jacky Marie
- Institut des Biomolécules
Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM,
Faculté de Pharmacie, 15 Avenue
Charles Flahault, BP 14491, 34093 Montpellier Cedex 05, France
| | - Alejandra Tomas
- Section
of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, London, W12 0NN, United Kingdom
| | - Dirk Trauner
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
- (D.T.) E-mail:
| | - Anja Hoffmann-Röder
- Department
of Chemistry and Center for Integrated Protein Science, LMU Munich, 81377 Munich, Germany
- (A.H.-R.) E-mail:
| | - David J. Hodson
- Institute
of Metabolism and Systems Research (IMSR), University of Birmingham, B15 2TT, Birmingham, United Kingdom
- Centre
for Endocrinology, Diabetes and Metabolism, Birmingham
Health Partners, Birmingham, B15 2TH, United Kingdom, and COMPARE University of Birmingham and University of Nottingham
Midlands
- (D.J.H.)
E-mail:
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15
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Halls ML, Canals M. Genetically Encoded FRET Biosensors to Illuminate Compartmentalised GPCR Signalling. Trends Pharmacol Sci 2017; 39:148-157. [PMID: 29054309 DOI: 10.1016/j.tips.2017.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 09/07/2017] [Accepted: 09/27/2017] [Indexed: 01/17/2023]
Abstract
Genetically encoded Förster resonance energy transfer (FRET) biosensors have been instrumental to our understanding of how intracellular signalling is organised and regulated within cells. In the last decade, the toolbox, dynamic range and applications of these sensors have expanded beyond basic cell biology applications. In particular, FRET biosensors have shed light onto the mechanisms that control the intracellular organisation of G protein-coupled receptor (GPCR) signalling and have allowed the visualisation of signalling events with unprecedented temporal and spatial resolution. Here we review the use of these sensors in the GPCR field and how it has already provided invaluable advances towards our understanding of the complexity of GPCR signalling.
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Affiliation(s)
- Michelle L Halls
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia.
| | - Meritxell Canals
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia.
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16
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Shahidullah M, Mandal A, Delamere NA. A Role for Calcium-Activated Adenylate Cyclase and Protein Kinase A in the Lens Src Family Kinase and Na,K-ATPase Response to Hyposmotic Stress. Invest Ophthalmol Vis Sci 2017; 58:4447-4456. [PMID: 28863406 PMCID: PMC6108779 DOI: 10.1167/iovs.17-21600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Na,K-ATPase activity in lens epithelium is subject to control by Src family tyrosine kinases (SFKs). Previously we showed hyposmotic solution causes an SFK-dependent increase in Na,K-ATPase activity in the epithelium. Here we explored the role of cAMP in the signaling mechanism responsible for the SFK and Na,K-ATPase response. Methods Intact porcine lenses were exposed to hyposmotic Krebs solution (200 mOsm) then the epithelium was assayed for cAMP, SFK phosphorylation (activation) or Na,K-ATPase activity. Results An increase of cAMP was observed in the epithelium of lenses exposed to hyposmotic solution. In lenses exposed to hyposmotic solution SFK phosphorylation in the epithelium approximately doubled as did Na,K-ATPase activity and both responses were prevented by H89, a protein kinase A inhibitor. The magnitude of the SFK response to hyposmotic solution was reduced by a TRPV4 antagonist HC067047 added to prevent TRPV4-mediated calcium entry, and by a cytoplasmic Ca2+ chelator BAPTA-AM. The Na,K-ATPase activity response in the epithelium of lenses exposed to hyposmotic solution was abolished by BAPTA-AM. As a direct test of cAMP-dependent SFK activation, intact lenses were exposed to 8-pCPT-cAMP, a cell-permeable cAMP analog. 8-pCPT-cAMP caused robust SFK activation. Using Western blot, two calcium-activated adenylyl cyclases, ADCY3 and ADCY8, were detected in lens epithelium. Conclusions Calcium-activated adenylyl cyclases are expressed in the lens epithelium and SFK activation is linked to a rise of cAMP that occurs upon hyposmotic challenge. The findings point to cAMP as a link between TRPV4 channel-mediated calcium entry, SFK activation, and a subsequent increase of Na,K-ATPase activity.
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Affiliation(s)
- Mohammad Shahidullah
- Department of Physiology, University of Arizona, Tucson, Arizona, United States.,Department of Ophthalmology & Vision Science, University of Arizona, Tucson, Arizona, United States
| | - Amritlal Mandal
- Department of Physiology, University of Arizona, Tucson, Arizona, United States
| | - Nicholas A Delamere
- Department of Physiology, University of Arizona, Tucson, Arizona, United States.,Department of Ophthalmology & Vision Science, University of Arizona, Tucson, Arizona, United States
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17
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Abstract
Genetically encoded fluorescent sensors are essential tools in modern biological research, and recent advances in fluorescent proteins (FPs) have expanded the scope of sensor design and implementation. In this review we compare different sensor platforms, including Förster resonance energy transfer (FRET) sensors, fluorescence-modulated single FP-based sensors, translocation sensors, complementation sensors, and dimerization-based sensors. We discuss elements of sensor design and engineering for each platform, including the incorporation of new types of FPs and sensor screening techniques. Finally, we summarize the wide range of sensors in the literature, exploring creative new sensor architectures suitable for different applications.
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Affiliation(s)
- Lynn Sanford
- University of Colorado Boulder, Boulder, CO, United States
| | - Amy Palmer
- University of Colorado Boulder, Boulder, CO, United States.
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18
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Quinn SN, Graves SH, Dains-McGahee C, Friedman EM, Hassan H, Witkowski P, Sabbatini ME. Adenylyl cyclase 3/adenylyl cyclase-associated protein 1 (CAP1) complex mediates the anti-migratory effect of forskolin in pancreatic cancer cells. Mol Carcinog 2016; 56:1344-1360. [PMID: 27891679 DOI: 10.1002/mc.22598] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/19/2016] [Accepted: 11/22/2016] [Indexed: 12/19/2022]
Abstract
Pancreatic cancer is one of the most lethal human malignancies. A better understanding of the intracellular mechanism of migration and invasion is urgently needed to develop treatment that will suppress metastases and improve overall survival. Cyclic adenosine monophosphate (cyclic AMP) is a second messenger that has shown to regulate migration and invasion of pancreatic cancer cells. The rise of cyclic AMP suppressed migration and invasion of pancreatic ductal adenocarcinoma cells. Cyclic AMP is formed from cytosolic ATP by the enzyme adenylyl cyclase (AC). There are ten isoforms of ACs; nine are anchored in the plasma membrane and one is soluble. What remains unknown is the extent to which the expression of transmembrane AC isoforms is both modified in pancreatic cancer and mediates the inhibitory effect of forskolin on cell motility. Using real-time PCR analysis, ADCY3 was found to be highly expressed in pancreatic tumor tissues, resulting in a constitutive increase in cyclic AMP levels. On the other hand, ADCY2 was down-regulated. Migration, invasion, and filopodia formation in two different pancreatic adenocarcinoma cell lines, HPAC and PANC-1 deficient in AC1 or AC3, were studied. We found that AC3, upon stimulation with forskolin, enhanced cyclic AMP levels and inhibited cell migration and invasion. Unlikely to be due to a cytotoxic effect, the inhibitory effects of forskolin involved the quick formation of AC3/adenylyl cyclase-associated protein 1 (CAP1)/G-actin complex, which inhibited filopodia formation and cell motility. Using Western blotting analysis, forskolin, through AC3 activation, caused phosphorylation of CREB, but not ERK. The effect of CREB phosphorylation is likely to be associated with long-term signaling changes. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Sierra N Quinn
- Department of Biological Sciences, Augusta University, Augusta, Georgia
| | - Sarai H Graves
- Department of Biological Sciences, Augusta University, Augusta, Georgia
| | | | - Emilee M Friedman
- Department of Biological Sciences, Augusta University, Augusta, Georgia
| | - Humma Hassan
- Department of Biological Sciences, Augusta University, Augusta, Georgia
| | - Piotr Witkowski
- Division of Abdominal Organ Transplantation, Department of Surgery, Pancreatic Islet Transplant Program, The University of Chicago Medical Center, Chicago, Illinois
| | - Maria E Sabbatini
- Department of Biological Sciences, Augusta University, Augusta, Georgia
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19
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Patel N, Gold MG. The genetically encoded tool set for investigating cAMP: more than the sum of its parts. Front Pharmacol 2015; 6:164. [PMID: 26300778 PMCID: PMC4526808 DOI: 10.3389/fphar.2015.00164] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/24/2015] [Indexed: 11/13/2022] Open
Abstract
Intracellular fluctuations of the second messenger cyclic AMP (cAMP) are regulated with spatial and temporal precision. This regulation is supported by the sophisticated arrangement of cyclases, phosphodiesterases, anchoring proteins, and receptors for cAMP. Discovery of these nuances to cAMP signaling has been facilitated by the development of genetically encodable tools for monitoring and manipulating cAMP and the proteins that support cAMP signaling. In this review, we discuss the state-of-the-art in development of different genetically encoded tools for sensing cAMP and the activity of its primary intracellular receptor protein kinase A (PKA). We introduce sequences for encoding adenylyl cyclases that enable cAMP levels to be artificially elevated within cells. We chart the evolution of sequences for selectively modifying protein-protein interactions that support cAMP signaling, and for driving cAMP sensors and manipulators to different subcellular locations. Importantly, these different genetically encoded tools can be applied synergistically, and we highlight notable instances that take advantage of this property. Finally, we consider prospects for extending the utility of the tool set to support further insights into the role of cAMP in health and disease.
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Affiliation(s)
- Neha Patel
- Department of Neuroscience, Physiology and Pharmacology, University College London London, UK
| | - Matthew G Gold
- Department of Neuroscience, Physiology and Pharmacology, University College London London, UK
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20
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Cooper DMF. Store-operated Ca²⁺-entry and adenylyl cyclase. Cell Calcium 2015; 58:368-75. [PMID: 25978874 DOI: 10.1016/j.ceca.2015.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Revised: 04/13/2015] [Accepted: 04/15/2015] [Indexed: 02/06/2023]
Abstract
One of the longest-standing effects of SOCE is in its selective regulation of Ca(2+)-sensitive adenylyl cyclase (AC) activity in non-excitable cells. Remarkably it was this source of Ca(2+) (SOCE) rather than the apparent magnitude of the Ca(2+)-rise that conferred AC responsiveness. The molecular basis for this dependence is now resolved in the case of adenylyl cyclase 8 (AC8). Sensors for Ca(2+) and cAMP targeted to ACs have been particularly useful in dissecting the influences upon and composition of what turn out to be signalling microdomains centred on ACs. A number of physiological processes depend on the regulation by SOCE of ACs, but the issue is under-studied. Here I will expand on these topics and point to some immediate unresolved questions.
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Affiliation(s)
- Dermot M F Cooper
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom.
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21
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Dou H, Wang C, Wu X, Yao L, Zhang X, Teng S, Xu H, Liu B, Wu Q, Zhang Q, Hu M, Wang Y, Wang L, Wu Y, Shang S, Kang X, Zheng L, Zhang J, Raoux M, Lang J, Li Q, Su J, Yu X, Chen L, Zhou Z. Calcium influx activates adenylyl cyclase 8 for sustained insulin secretion in rat pancreatic beta cells. Diabetologia 2015; 58:324-33. [PMID: 25381556 DOI: 10.1007/s00125-014-3437-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/08/2014] [Indexed: 01/07/2023]
Abstract
AIMS/HYPOTHESIS Insulin is a key metabolic regulator in health and diabetes. In pancreatic beta cells, insulin release is regulated by the major second messengers Ca(2+) and cAMP: exocytosis is triggered by Ca(2+) and mediated by the cAMP/protein kinase A (PKA) signalling pathway. However, the causal link between these two processes in primary beta cells remains undefined. METHODS Time-resolved confocal imaging of fluorescence resonance energy transfer signals was performed to visualise PKA activity, and combined membrane capacitance recordings were used to monitor insulin secretion from patch-clamped rat beta cells. RESULTS Membrane depolarisation-induced Ca(2+) influx caused an increase in cytosolic PKA activity via activating a Ca(2+)-sensitive adenylyl cyclase 8 (ADCY8) subpool. Glucose stimulation triggered coupled Ca(2+) oscillations and PKA activation. ADCY8 knockdown significantly reduced the level of depolarisation-evoked PKA activation and impaired replenishment of the readily releasable vesicle pool. Pharmacological inhibition of PKA by two inhibitors reduced depolarisation-induced PKA activation to a similar extent and reduced the capacity for sustained vesicle exocytosis and insulin release. CONCLUSIONS/INTERPRETATION Our findings suggest that depolarisation-induced Ca(2+) influx plays dual roles in regulating exocytosis in rat pancreatic beta cells by triggering vesicle fusion and replenishing the vesicle pool to support sustained insulin release. Therefore, Ca(2+) influx may be important for glucose-stimulated insulin secretion.
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Affiliation(s)
- Haiqiang Dou
- Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
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22
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Abstract
Recent advances in the AC (adenylate cyclase)/cAMP field reveal overarching roles for the ACs. Whereas few processes are unaffected by cAMP in eukaryotes, ranging from the rapid modulation of ion channel kinetics to the slowest developmental effects, the large number of cellular processes modulated by only three intermediaries, i.e. PKA (protein kinase A), Epacs (exchange proteins directly activated by cAMP) and CNG (cyclic nucleotide-gated) channels, poses the question of how selectivity and fine control is achieved by cAMP. One answer rests on the number of differently regulated and distinctly expressed AC species. Specific ACs are implicated in processes such as insulin secretion, immunological responses, sino-atrial node pulsatility and memory formation, and specific ACs are linked with particular diseased conditions or predispositions, such as cystic fibrosis, Type 2 diabetes and dysrhythmias. However, much of the selectivity and control exerted by cAMP lies in the sophisticated properties of individual ACs, in terms of their coincident responsiveness, dynamic protein scaffolding and organization of cellular microassemblies. The ACs appear to be the centre of highly organized microdomains, where both cAMP and Ca2+, the other major influence on ACs, change in patterns quite discrete from the broad cellular milieu. How these microdomains are organized is beginning to become clear, so that ACs may now be viewed as fundamental signalling centres, whose properties exceed their production of cAMP. In the present review, we summarize how ACs are multiply regulated and the steps that are put in place to ensure discrimination in their signalling. This includes scaffolding of targets and modulators by the ACs and assembling of signalling nexuses in discrete cellular domains. We also stress how these assemblies are cell-specific, context-specific and dynamic, and may be best addressed by targeted biosensors. These perspectives on the organization of ACs uncover new strategies for intervention in systems mediated by cAMP, which promise far more informed specificity than traditional approaches.
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23
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Smedler E, Malmersjö S, Uhlén P. Network analysis of time-lapse microscopy recordings. Front Neural Circuits 2014; 8:111. [PMID: 25278844 PMCID: PMC4166320 DOI: 10.3389/fncir.2014.00111] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 08/27/2014] [Indexed: 12/30/2022] Open
Abstract
Multicellular organisms rely on intercellular communication to regulate important cellular processes critical to life. To further our understanding of those processes there is a need to scrutinize dynamical signaling events and their functions in both cells and organisms. Here, we report a method and provide MATLAB code that analyzes time-lapse microscopy recordings to identify and characterize network structures within large cell populations, such as interconnected neurons. The approach is demonstrated using intracellular calcium (Ca2+) recordings in neural progenitors and cardiac myocytes, but could be applied to a wide variety of biosensors employed in diverse cell types and organisms. In this method, network structures are analyzed by applying cross-correlation signal processing and graph theory to single-cell recordings. The goal of the analysis is to determine if the single cell activity constitutes a network of interconnected cells and to decipher the properties of this network. The method can be applied in many fields of biology in which biosensors are used to monitor signaling events in living cells. Analyzing intercellular communication in cell ensembles can reveal essential network structures that provide important biological insights.
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Affiliation(s)
- Erik Smedler
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet Stockholm, Sweden
| | - Seth Malmersjö
- Department of Chemical and Systems Biology, School of Medicine, Stanford University Stanford, CA, USA
| | - Per Uhlén
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet Stockholm, Sweden
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24
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Hodson DJ, Mitchell RK, Marselli L, Pullen TJ, Gimeno Brias S, Semplici F, Everett KL, Cooper DMF, Bugliani M, Marchetti P, Lavallard V, Bosco D, Piemonti L, Johnson PR, Hughes SJ, Li D, Li WH, Shapiro AMJ, Rutter GA. ADCY5 couples glucose to insulin secretion in human islets. Diabetes 2014; 63:3009-21. [PMID: 24740569 PMCID: PMC4141364 DOI: 10.2337/db13-1607] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 04/10/2014] [Indexed: 01/10/2023]
Abstract
Single nucleotide polymorphisms (SNPs) within the ADCY5 gene, encoding adenylate cyclase 5, are associated with elevated fasting glucose and increased type 2 diabetes (T2D) risk. Despite this, the mechanisms underlying the effects of these polymorphic variants at the level of pancreatic β-cells remain unclear. Here, we show firstly that ADCY5 mRNA expression in islets is lowered by the possession of risk alleles at rs11708067. Next, we demonstrate that ADCY5 is indispensable for coupling glucose, but not GLP-1, to insulin secretion in human islets. Assessed by in situ imaging of recombinant probes, ADCY5 silencing impaired glucose-induced cAMP increases and blocked glucose metabolism toward ATP at concentrations of the sugar >8 mmol/L. However, calcium transient generation and functional connectivity between individual human β-cells were sharply inhibited at all glucose concentrations tested, implying additional, metabolism-independent roles for ADCY5. In contrast, calcium rises were unaffected in ADCY5-depleted islets exposed to GLP-1. Alterations in β-cell ADCY5 expression and impaired glucose signaling thus provide a likely route through which ADCY5 gene polymorphisms influence fasting glucose levels and T2D risk, while exerting more minor effects on incretin action.
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Affiliation(s)
- David J Hodson
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K.
| | - Ryan K Mitchell
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K
| | - Lorella Marselli
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Timothy J Pullen
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K
| | - Silvia Gimeno Brias
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K
| | - Francesca Semplici
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K
| | - Katy L Everett
- Department of Pharmacology, University of Cambridge, Cambridge, U.K
| | | | - Marco Bugliani
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Vanessa Lavallard
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Domenico Bosco
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Lorenzo Piemonti
- Diabetes Research Institute, San Raffaele Scientific Institute, Milan, Italy
| | - Paul R Johnson
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, U.K. Oxford Centre for Diabetes, Endocrinology, and Metabolism, University of Oxford, Oxford, U.K. National Institute of Health Research Oxford Biomedical Research Centre, Churchill Hospital, Oxford, U.K
| | - Stephen J Hughes
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, U.K. Oxford Centre for Diabetes, Endocrinology, and Metabolism, University of Oxford, Oxford, U.K. National Institute of Health Research Oxford Biomedical Research Centre, Churchill Hospital, Oxford, U.K
| | - Daliang Li
- University of Texas Southwestern Medical Center, Dallas, TX
| | - Wen-Hong Li
- University of Texas Southwestern Medical Center, Dallas, TX
| | - A M James Shapiro
- Clinical Islet Laboratory and Clinical Islet Transplant Program, University of Alberta, Edmonton, Alberta, Canada
| | - Guy A Rutter
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, U.K.
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25
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Mehta S, Aye-Han NN, Ganesan A, Oldach L, Gorshkov K, Zhang J. Calmodulin-controlled spatial decoding of oscillatory Ca2+ signals by calcineurin. eLife 2014; 3:e03765. [PMID: 25056880 PMCID: PMC4141273 DOI: 10.7554/elife.03765] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Calcineurin is responsible for mediating a wide variety of cellular processes in response to dynamic calcium (Ca(2+)) signals, yet the precise mechanisms involved in the spatiotemporal control of calcineurin signaling are poorly understood. Here, we use genetically encoded fluorescent biosensors to directly probe the role of cytosolic Ca(2+) oscillations in modulating calcineurin activity dynamics in insulin-secreting MIN6 β-cells. We show that Ca(2+) oscillations induce distinct temporal patterns of calcineurin activity in the cytosol and plasma membrane vs at the ER and mitochondria in these cells. Furthermore, we found that these differential calcineurin activity patterns are determined by variations in the subcellular distribution of calmodulin (CaM), indicating that CaM plays an active role in shaping both the spatial and temporal aspects of calcineurin signaling. Together, our findings provide new insights into the mechanisms by which oscillatory signals are decoded to generate specific functional outputs within different cellular compartments.
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Affiliation(s)
- Sohum Mehta
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Nwe-Nwe Aye-Han
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Ambhighainath Ganesan
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, United States
| | - Laurel Oldach
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Kirill Gorshkov
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jin Zhang
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, United States Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, United States
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26
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cAMP and Ca²⁺ signaling in secretory epithelia: crosstalk and synergism. Cell Calcium 2014; 55:385-93. [PMID: 24613710 DOI: 10.1016/j.ceca.2014.01.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 01/29/2014] [Accepted: 01/30/2014] [Indexed: 12/15/2022]
Abstract
The Ca(2+) and cAMP/PKA pathways are the primary signaling systems in secretory epithelia that control virtually all secretory gland functions. Interaction and crosstalk in Ca(2+) and cAMP signaling occur at multiple levels to control and tune the activity of each other. Physiologically, Ca(2+) and cAMP signaling operate at 5-10% of maximal strength, but synergize to generate the maximal response. Although synergistic action of the Ca(2+) and cAMP signaling is the common mode of signaling and has been known for many years, we know very little of the molecular mechanism and mediators of the synergism. In this review, we discuss crosstalk between the Ca(2+) and cAMP signaling and the function of IRBIT (IP3 receptors binding protein release with IP3) as a third messenger that mediates the synergistic action of the Ca(2+) and cAMP signaling.
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