1
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Olsen RH, English JG. Advancements in G protein-coupled receptor biosensors to study GPCR-G protein coupling. Br J Pharmacol 2023; 180:1433-1443. [PMID: 36166832 PMCID: PMC10511148 DOI: 10.1111/bph.15962] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 11/28/2022] Open
Abstract
Enzymatic and cellular signalling biosensors are used to decipher the activities of complex biological systems. Biosensors for monitoring G protein-coupled receptors (GPCRs), the most drugged class of proteins in the human body, are plentiful and vary in utility, form and function. Their applications have continually expanded our understanding of this important protein class. Here, we briefly summarize a subset of this field with accelerating importance: transducer biosensors measuring receptor-coupling and selectivity, with an emphasis on sensors measuring receptor association and activation of heterotrimeric signalling complexes.
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Affiliation(s)
| | - Justin G. English
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84132 USA
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2
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Berg JA, Zhou Y, Ouyang Y, Cluntun AA, Waller TC, Conway ME, Nowinski SM, Van Ry T, George I, Cox JE, Wang B, Rutter J. Metaboverse enables automated discovery and visualization of diverse metabolic regulatory patterns. Nat Cell Biol 2023; 25:616-625. [PMID: 37012464 PMCID: PMC10104781 DOI: 10.1038/s41556-023-01117-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 02/24/2023] [Indexed: 04/05/2023]
Abstract
Metabolism is intertwined with various cellular processes, including controlling cell fate, influencing tumorigenesis, participating in stress responses and more. Metabolism is a complex, interdependent network, and local perturbations can have indirect effects that are pervasive across the metabolic network. Current analytical and technical limitations have long created a bottleneck in metabolic data interpretation. To address these shortcomings, we developed Metaboverse, a user-friendly tool to facilitate data exploration and hypothesis generation. Here we introduce algorithms that leverage the metabolic network to extract complex reaction patterns from data. To minimize the impact of missing measurements within the network, we introduce methods that enable pattern recognition across multiple reactions. Using Metaboverse, we identify a previously undescribed metabolite signature that correlated with survival outcomes in early stage lung adenocarcinoma patients. Using a yeast model, we identify metabolic responses suggesting an adaptive role of citrate homeostasis during mitochondrial dysfunction facilitated by the citrate transporter, Ctp1. We demonstrate that Metaboverse augments the user's ability to extract meaningful patterns from multi-omics datasets to develop actionable hypotheses.
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Affiliation(s)
- Jordan A Berg
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
- Altos Labs, Redwood City, CA, USA.
| | - Youjia Zhou
- School of Computing, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
| | - Yeyun Ouyang
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Altos Labs, Redwood City, CA, USA
| | - Ahmad A Cluntun
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - T Cameron Waller
- Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Megan E Conway
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Sara M Nowinski
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Tyler Van Ry
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Metabolomics Core Facility, University of Utah, Salt Lake City, UT, USA
- College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - Ian George
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - James E Cox
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Metabolomics Core Facility, University of Utah, Salt Lake City, UT, USA
- Diabetes & Metabolism Research Center, University of Utah, Salt Lake City, UT, USA
| | - Bei Wang
- School of Computing, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
| | - Jared Rutter
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
- Diabetes & Metabolism Research Center, University of Utah, Salt Lake City, UT, USA.
- Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT, USA.
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3
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Huang SK, Picard LP, Rahmatullah RSM, Pandey A, Van Eps N, Sunahara RK, Ernst OP, Sljoka A, Prosser RS. Mapping the conformational landscape of the stimulatory heterotrimeric G protein. Nat Struct Mol Biol 2023; 30:502-511. [PMID: 36997760 DOI: 10.1038/s41594-023-00957-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 02/24/2023] [Indexed: 04/01/2023]
Abstract
Heterotrimeric G proteins serve as membrane-associated signaling hubs, in concert with their cognate G-protein-coupled receptors. Fluorine nuclear magnetic resonance spectroscopy was employed to monitor the conformational equilibria of the human stimulatory G-protein α subunit (Gsα) alone, in the intact Gsαβ1γ2 heterotrimer or in complex with membrane-embedded human adenosine A2A receptor (A2AR). The results reveal a concerted equilibrium that is strongly affected by nucleotide and interactions with the βγ subunit, the lipid bilayer and A2AR. The α1 helix of Gsα exhibits significant intermediate timescale dynamics. The α4β6 loop and α5 helix undergo membrane/receptor interactions and order-disorder transitions respectively, associated with G-protein activation. The αN helix adopts a key functional state that serves as an allosteric conduit between the βγ subunit and receptor, while a significant fraction of the ensemble remains tethered to the membrane and receptor upon activation.
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Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | | | - Rima S M Rahmatullah
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | - Aditya Pandey
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | - Ned Van Eps
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Roger K Sunahara
- Department of Pharmacology, University of California San Diego School of Medicine, La Jolla, CA, USA
| | - Oliver P Ernst
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Adnan Sljoka
- RIKEN Center for Advanced Intelligence Project, RIKEN, Tokyo, Japan.
| | - R Scott Prosser
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada.
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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4
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Kroning KE, Wang W. Genetically encoded tools for in vivo G-protein-coupled receptor agonist detection at cellular resolution. Clin Transl Med 2022; 12:e1124. [PMID: 36446954 PMCID: PMC9708909 DOI: 10.1002/ctm2.1124] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/10/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are the most abundant receptor type in the human body and are responsible for regulating many physiological processes, such as sensation, cognition, muscle contraction and metabolism. Further, GPCRs are widely expressed in the brain where their agonists make up a large number of neurotransmitters and neuromodulators. Due to the importance of GPCRs in human physiology, genetically encoded sensors have been engineered to detect GPCR agonists at cellular resolution in vivo. These sensors can be placed into two main categories: those that offer real-time information on the signalling dynamics of GPCR agonists and those that integrate the GPCR agonist signal into a permanent, quantifiable mark that can be used to detect GPCR agonist localisation in a large brain area. In this review, we discuss the various designs of real-time and integration sensors, their advantages and limitations, and some in vivo applications. We also discuss the potential of using real-time and integrator sensors together to identify neuronal circuits affected by endogenous GPCR agonists and perform detailed characterisations of the spatiotemporal dynamics of GPCR agonist release in those circuits. By using these sensors together, the overall knowledge of GPCR-mediated signalling can be expanded.
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Affiliation(s)
- Kayla E. Kroning
- Life Sciences Institute, University of MichiganAnn ArborMichiganUSA
- Department of ChemistryUniversity of MichiganAnn ArborMichiganUSA
| | - Wenjing Wang
- Life Sciences Institute, University of MichiganAnn ArborMichiganUSA
- Department of ChemistryUniversity of MichiganAnn ArborMichiganUSA
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5
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Gq Signaling in Autophagy Control: Between Chemical and Mechanical Cues. Antioxidants (Basel) 2022; 11:antiox11081599. [PMID: 36009317 PMCID: PMC9405508 DOI: 10.3390/antiox11081599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 11/17/2022] Open
Abstract
All processes in human physiology relies on homeostatic mechanisms which require the activation of specific control circuits to adapt the changes imposed by external stimuli. One of the critical modulators of homeostatic balance is autophagy, a catabolic process that is responsible of the destruction of long-lived proteins and organelles through a lysosome degradative pathway. Identification of the mechanism underlying autophagic flux is considered of great importance as both protective and detrimental functions are linked with deregulated autophagy. At the mechanistic and regulatory levels, autophagy is activated in response to diverse stress conditions (food deprivation, hyperthermia and hypoxia), even a novel perspective highlight the potential role of physical forces in autophagy modulation. To understand the crosstalk between all these controlling mechanisms could give us new clues about the specific contribution of autophagy in a wide range of diseases including vascular disorders, inflammation and cancer. Of note, any homeostatic control critically depends in at least two additional and poorly studied interdependent components: a receptor and its downstream effectors. Addressing the selective receptors involved in autophagy regulation is an open question and represents a new area of research in this field. G-protein coupled receptors (GPCRs) represent one of the largest and druggable targets membrane receptor protein superfamily. By exerting their action through G proteins, GPCRs play fundamental roles in the control of cellular homeostasis. Novel studies have shown Gαq, a subunit of heterotrimeric G proteins, as a core modulator of mTORC1 and autophagy, suggesting a fundamental contribution of Gαq-coupled GPCRs mechanisms in the control of this homeostatic feedback loop. To address how GPCR-G proteins machinery integrates the response to different stresses including oxidative conditions and mechanical stimuli, could provide deeper insight into new signaling pathways and open potential and novel therapeutic strategies in the modulation of different pathological conditions.
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6
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Guo S, Zhao T, Yun Y, Xie X. Recent Progress in Assays for GPCR Drug Discovery. Am J Physiol Cell Physiol 2022; 323:C583-C594. [PMID: 35816640 DOI: 10.1152/ajpcell.00464.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
G-protein coupled receptors (GPCRs), also known as 7 transmembrane receptors, are the largest family of cell surface receptors in eukaryotes. There are ~800 GPCRs in human, regulating diverse physiological processes. GPCRs are the most intensively studied drug targets. Drugs that target GPCRs account for about a quarter of the global market share of therapeutic drugs. Therefore, to develop physiologically relevant and robust assays to search new GPCR ligands or modulators remain the major focus of drug discovery research worldwide. Early functional GPCR assays are mainly depend on the measurement of G protein-mediated second messenger generation. Recent development in GPCR biology indicate the signaling of these receptors is much more complex than the oversimplified classical view. GPCRs have been found to activate multiple G proteins simultaneously and induce b-arrestin-mediated signaling. GPCRs have also been found to interacte with other cytosolic scaffolding proteins and form dimer or heteromer with GPCRs or other transmembrane proteins. Here we mainly discuss technologies focused on detecting protein-protein interactions, such as FRET/BRET, NanoBiT, Tango, etc, and their applications in measuring GPCRs interacting with various signaling partners. In the final part, we also discuss the species differences in GPCRs when using animal models to study the in vivofunctions of GPCR ligands, and possible ways to solve this problem with modern genetic tools.
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Affiliation(s)
- Shimeng Guo
- grid.419093.6Shanghai Institute of Materia Medica, Shanghai, China
| | - Tingting Zhao
- grid.419093.6Shanghai Institute of Materia Medica, Shanghai, China
| | - Ying Yun
- grid.419093.6Shanghai Institute of Materia Medica, Shanghai, China
| | - Xin Xie
- grid.419093.6Shanghai Institute of Materia Medica, Shanghai, China
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7
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Lim J, Petersen M, Bunz M, Simon C, Schindler M. Flow cytometry based-FRET: basics, novel developments and future perspectives. Cell Mol Life Sci 2022; 79:217. [PMID: 35352201 PMCID: PMC8964568 DOI: 10.1007/s00018-022-04232-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/07/2022] [Indexed: 12/29/2022]
Abstract
Förster resonance energy transfer (FRET) is a widespread technology used to analyze and quantify protein interactions in multiple settings. While FRET is traditionally measured by microscopy, flow cytometry based-FRET is becoming popular within the last decade and more commonly used. Flow cytometry based-FRET offers the possibility to assess FRET in a short time-frame in a high number of cells thereby allowing stringent and statistically robust quantification of FRET in multiple samples. Furthermore, established, simple and easy to implement gating strategies facilitate the adaptation of flow cytometry based-FRET measurements to most common flow cytometers. We here summarize the basics of flow cytometry based-FRET, highlight recent novel developments in this field and emphasize on exciting future perspectives.
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Affiliation(s)
- JiaWen Lim
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Moritz Petersen
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Maximilian Bunz
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Claudia Simon
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Michael Schindler
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany.
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8
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BRET-Based Biosensors to Measure Agonist Efficacies in Histamine H 1 Receptor-Mediated G Protein Activation, Signaling and Interactions with GRKs and β-Arrestins. Int J Mol Sci 2022; 23:ijms23063184. [PMID: 35328605 PMCID: PMC8953162 DOI: 10.3390/ijms23063184] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/04/2023] Open
Abstract
The histamine H1 receptor (H1R) is a G protein-coupled receptor (GPCR) and plays a key role in allergic reactions upon activation by histamine which is locally released from mast cells and basophils. Consequently, H1R is a well-established therapeutic target for antihistamines that relieve allergy symptoms. H1R signals via heterotrimeric Gq proteins and is phosphorylated by GPCR kinase (GRK) subtypes 2, 5, and 6, consequently facilitating the subsequent recruitment of β-arrestin1 and/or 2. Stimulation of a GPCR with structurally different agonists can result in preferential engagement of one or more of these intracellular signaling molecules. To evaluate this so-called biased agonism for H1R, bioluminescence resonance energy transfer (BRET)-based biosensors were applied to measure H1R signaling through heterotrimeric Gq proteins, second messengers (inositol 1,4,5-triphosphate and Ca2+), and receptor-protein interactions (GRKs and β-arrestins) in response to histamine, 2-phenylhistamines, and histaprodifens in a similar cellular background. Although differences in efficacy were observed for these agonists between some functional readouts as compared to reference agonist histamine, subsequent data analysis using an operational model of agonism revealed only signaling bias of the agonist Br-phHA-HA in recruiting β-arrestin2 to H1R over Gq biosensor activation.
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9
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Huang SK, Prosser RS. Dynamics and Mechanistic Underpinnings to Pharmacology of Class A GPCRs - An NMR Perspective. Am J Physiol Cell Physiol 2022; 322:C739-C753. [PMID: 35235425 DOI: 10.1152/ajpcell.00044.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
One-third of current pharmaceuticals target G protein-coupled receptors (GPCRs), the largest receptor superfamily in humans and mediators of diverse physiological processes. This review summarizes the recent progress in GPCR structural dynamics, focusing on class A receptors and insights derived from nuclear magnetic resonance (NMR) and other spectroscopic techniques. We describe the structural aspects of GPCR activation and the various pharmacological models that capture aspects of receptor signaling behaviour. Spectroscopic studies revealed that receptors and their signaling complexes are dynamic allosteric systems that sample multiple functional states under basal conditions. The distribution of states within the conformational ensemble and the kinetics of transitions between states are regulated through the binding of ligands, allosteric modulators, and the membrane environment. This ensemble view of GPCRs provides a mechanistic framework for understanding many of the pharmacological phenomena associated with receptor signaling, such as basal activity, efficacy, and functional bias.
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Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada.,Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - R Scott Prosser
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada.,Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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10
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Singh K, Senatorov IS, Cheshmehkani A, Karmokar PF, Moniri NH. The skeletal muscle relaxer cyclobenzaprine is a potent non-competitive antagonist of histamine H1 receptors. J Pharmacol Exp Ther 2022; 380:202-209. [PMID: 34992159 DOI: 10.1124/jpet.121.000998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 01/02/2021] [Indexed: 11/22/2022] Open
Abstract
Cyclobenzaprine is a tricyclic dimethylpropanamine skeletal muscle relaxant, which is used clinically to decrease muscle spasm and hypercontractility, as well as acute musculoskeletal pain. Although the absolute mechanism of action of cyclobenzaprine remains elusive, it is known to mediate its effects centrally, via inhibition of tonic somatic motor function, likely through modulation of noradrenergic and serotonergic systems. While cyclobenzaprine is effective as a muscle relaxant, greater than 30% of patients experience drowsiness and sedative/hypnotic effects, yet, the mechanisms that cause this adverse effect is also undescribed. Based on this common adverse effect profile and the structural similarity of cyclobenzaprine to tricyclic antidepressants, as well as ethanolamine first-generation antihistamines, we hypothesized that cyclobenzaprine facilitates sedative effects via off-target antagonism of central histamine H1 receptors (H1R). Here, for the first time, we present data that demonstrate that cyclobenzaprine exhibits low nanomolar affinity for the cloned human H1R, as well as that expressed in both rat and mouse brain. Using saturation radioligand binding, we also demonstrate that cyclobenzaprine binds to the H1R in a non-competitive manner. Similarly, functional assays measuring both Ca+2 influx and novel TRUPATH G-protein subunit BRET biosensors reveal that cyclobenzaprine also blocks histamine-mediated H1R functional activity in a non-competitive manner, whereas the classical H1R antagonist diphenhydramine does so competitively. Given that cyclobenzaprine readily crosses the blood-brain barrier and its muscle relaxant effects occur centrally, our data suggest that off-target central antagonism of H1R by cyclobenzaprine facilitates the significant sedative effect of this agent seen in patients. Significance Statement Cyclobenzaprine, a clinically used muscle relaxant that is strongly linked to sedation, demonstrates high affinity non-competitive antagonism at the histamine H1 receptor. This effect likely modulates the high degree of sedation patients experience.
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Affiliation(s)
- Kirti Singh
- Pharmaceutical Sciences, Mercer University, United States
| | | | | | | | - Nader H Moniri
- Pharmaceutical Sciences, Mercer Univeristy, United States
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11
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Hussain M, Cummins MC, Endo-Streeter S, Sondek J, Kuhlman B. Designer proteins that competitively inhibit Gα q by targeting its effector site. J Biol Chem 2021; 297:101348. [PMID: 34715131 PMCID: PMC8633581 DOI: 10.1016/j.jbc.2021.101348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 10/12/2021] [Accepted: 10/22/2021] [Indexed: 11/30/2022] Open
Abstract
During signal transduction, the G protein, Gαq, binds and activates phospholipase C-β isozymes. Several diseases have been shown to manifest upon constitutively activating mutation of Gαq, such as uveal melanoma. Therefore, methods are needed to directly inhibit Gαq. Previously, we demonstrated that a peptide derived from a helix-turn-helix (HTH) region of PLC-β3 (residues 852-878) binds Gαq with low micromolar affinity and inhibits Gαq by competing with full-length PLC-β isozymes for binding. Since the HTH peptide is unstructured in the absence of Gαq, we hypothesized that embedding the HTH in a folded protein might stabilize the binding-competent conformation and further improve the potency of inhibition. Using the molecular modeling software Rosetta, we searched the Protein Data Bank for proteins with similar HTH structures near their surface. The candidate proteins were computationally docked against Gαq, and their surfaces were redesigned to stabilize this interaction. We then used yeast surface display to affinity mature the designs. The most potent design bound Gαq/i with high affinity in vitro (KD = 18 nM) and inhibited activation of PLC-β isozymes in HEK293 cells. We anticipate that our genetically encoded inhibitor will help interrogate the role of Gαq in healthy and disease model systems. Our work demonstrates that grafting interaction motifs into folded proteins is a powerful approach for generating inhibitors of protein-protein interactions.
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Affiliation(s)
- Mahmud Hussain
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Matthew C Cummins
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Stuart Endo-Streeter
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - John Sondek
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA.
| | - Brian Kuhlman
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA.
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12
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Schihada H, Shekhani R, Schulte G. Quantitative assessment of constitutive G protein-coupled receptor activity with BRET-based G protein biosensors. Sci Signal 2021; 14:eabf1653. [PMID: 34516756 DOI: 10.1126/scisignal.abf1653] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Hannes Schihada
- Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, Biomedicum, Solnavägen 9, SE-17165 Stockholm, Sweden
| | - Rawan Shekhani
- Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, Biomedicum, Solnavägen 9, SE-17165 Stockholm, Sweden
| | - Gunnar Schulte
- Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, Biomedicum, Solnavägen 9, SE-17165 Stockholm, Sweden
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13
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Barvitenko N, Aslam M, Lawen A, Saldanha C, Skverchinskaya E, Uras G, Manca A, Pantaleo A. Two Motors and One Spring: Hypothetic Roles of Non-Muscle Myosin II and Submembrane Actin-Based Cytoskeleton in Cell Volume Sensing. Int J Mol Sci 2021; 22:7967. [PMID: 34360739 PMCID: PMC8347689 DOI: 10.3390/ijms22157967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/16/2021] [Accepted: 07/23/2021] [Indexed: 12/12/2022] Open
Abstract
Changes in plasma membrane curvature and intracellular ionic strength are two key features of cell volume perturbations. In this hypothesis we present a model of the responsible molecular apparatus which is assembled of two molecular motors [non-muscle myosin II (NMMII) and protrusive actin polymerization], a spring [a complex between the plasma membrane (PM) and the submembrane actin-based cytoskeleton (smACSK) which behaves like a viscoelastic solid] and the associated signaling proteins. We hypothesize that this apparatus senses changes in both the plasma membrane curvature and the ionic strength and in turn activates signaling pathways responsible for regulatory volume increase (RVI) and regulatory volume decrease (RVD). During cell volume changes hydrostatic pressure (HP) changes drive alterations in the cell membrane curvature. HP difference has opposite directions in swelling versus shrinkage, thus allowing distinction between them. By analogy with actomyosin contractility that appears to sense stiffness of the extracellular matrix we propose that NMMII and actin polymerization can actively probe the transmembrane gradient in HP. Furthermore, NMMII and protein-protein interactions in the actin cortex are sensitive to ionic strength. Emerging data on direct binding to and regulating activities of transmembrane mechanosensors by NMMII and actin cortex provide routes for signal transduction from transmembrane mechanosensors to cell volume regulatory mechanisms.
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Affiliation(s)
| | - Muhammad Aslam
- Department of Internal Medicine I, Experimental Cardiology, Justus Liebig University, 35392 Giessen, Germany;
| | - Alfons Lawen
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia;
| | - Carlota Saldanha
- Institute of Biochemistry, Institute of Molecular Medicine, Faculty of Medicine University of Lisbon, 1649-028 Lisboa, Portugal;
| | | | - Giuseppe Uras
- Department of Clinical and Movement Neurosciences, Institute of Neurology, University College London, London NW3 2PF, UK;
| | - Alessia Manca
- Department of Biomedical Science, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy;
| | - Antonella Pantaleo
- Department of Biomedical Science, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy;
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14
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Zhou Y, Meng J, Xu C, Liu J. Multiple GPCR Functional Assays Based on Resonance Energy Transfer Sensors. Front Cell Dev Biol 2021; 9:611443. [PMID: 34041234 PMCID: PMC8141573 DOI: 10.3389/fcell.2021.611443] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/05/2021] [Indexed: 12/19/2022] Open
Abstract
G protein-coupled receptors (GPCRs) represent one of the largest membrane protein families that participate in various physiological and pathological activities. Accumulating structural evidences have revealed how GPCR activation induces conformational changes to accommodate the downstream G protein or β-arrestin. Multiple GPCR functional assays have been developed based on Förster resonance energy transfer (FRET) and bioluminescence resonance energy transfer (BRET) sensors to monitor the conformational changes in GPCRs, GPCR/G proteins, or GPCR/β-arrestin, especially over the past two decades. Here, we will summarize how these sensors have been optimized to increase the sensitivity and compatibility for application in different GPCR classes using various labeling strategies, meanwhile provide multiple solutions in functional assays for high-throughput drug screening.
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Affiliation(s)
- Yiwei Zhou
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Jiyong Meng
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Chanjuan Xu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China.,Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Jianfeng Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China.,Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
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15
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McNeill SM, Baltos JA, White PJ, May LT. Biased agonism at adenosine receptors. Cell Signal 2021; 82:109954. [PMID: 33610717 DOI: 10.1016/j.cellsig.2021.109954] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/11/2021] [Accepted: 02/13/2021] [Indexed: 01/14/2023]
Abstract
Adenosine modulates many aspects of human physiology and pathophysiology through binding to the adenosine family of G protein-coupled receptors, which are comprised of four subtypes, the A1R, A2AR, A2BR and A3R. Modulation of adenosine receptor function by exogenous agonists, antagonists and allosteric modulators can be beneficial for a number of conditions including cardiovascular disease, Parkinson's disease, and cancer. Unfortunately, many preclinical drug candidates targeting adenosine receptors have failed in clinical trials due to limited efficacy and/or severe on-target undesired effects. To overcome the key barriers typically encountered when transitioning adenosine receptor ligands into the clinic, research efforts have focussed on exploiting the phenomenon of biased agonism. Biased agonism provides the opportunity to develop ligands that favour therapeutic signalling pathways, whilst avoiding signalling associated with on-target undesired effects. Recent studies have begun to define the structure-function relationships that underpin adenosine receptor biased agonism and establish how this phenomenon can be harnessed therapeutically. In this review we describe the recent advancements made towards achieving therapeutically relevant biased agonism at adenosine receptors.
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Affiliation(s)
- Samantha M McNeill
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia
| | - Jo-Anne Baltos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia; Department of Pharmacology, Monash University, Melbourne, VIC, Australia.
| | - Paul J White
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia
| | - Lauren T May
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia; Department of Pharmacology, Monash University, Melbourne, VIC, Australia.
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16
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Shahraki A, Işbilir A, Dogan B, Lohse MJ, Durdagi S, Birgul-Iyison N. Structural and Functional Characterization of Allatostatin Receptor Type-C of Thaumetopoea pityocampa, a Potential Target for Next-Generation Pest Control Agents. J Chem Inf Model 2021; 61:715-728. [PMID: 33476150 DOI: 10.1021/acs.jcim.0c00985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Insect neuropeptide receptors, including allatostatin receptor type C (AstR-C), a G protein-coupled receptor, are among the potential targets for designing next-generation pesticides that despite their importance in offering a new mode-of-action have been overlooked. Focusing on AstR-C of Thaumetopoea pityocampa, a common pest in Mediterranean countries, by employing resonance energy transfer-based methods, we showed Gαi/o coupling and β-arrestin recruitment of the receptor at sub-nanomolar and nanomolar ranges of the endogenous ligand, AST-C, respectively. Molecular docking and molecular dynamics simulation studies revealed the importance of extracellular loop 2 in AstRC/AST-C interaction, and a combination of in silico and in vitro approaches showed the substantial role of Q2716.55 in G protein-dependent activation of AstR-C possibly via contributing to the flexibility of the receptor's structure. The functional and structural insights obtained on T. pit AstR-C positively assist future efforts in developing environmentally friendly pest control agents that are needed urgently.
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Affiliation(s)
- Aida Shahraki
- Department of Molecular Biology and Genetics, Bogazici University, 34342 Istanbul, Turkey.,Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, 34734 Istanbul, Turkey
| | - Ali Işbilir
- Max Delbrück Center for Molecular Medicine in Helmholz Association, 13125 Berlin, Germany.,Institute of Pharmacology and Toxicology, University of Würzburg, 97078 Würzburg, Germany
| | - Berna Dogan
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, 34734 Istanbul, Turkey
| | - Martin J Lohse
- Max Delbrück Center for Molecular Medicine in Helmholz Association, 13125 Berlin, Germany.,Institute of Pharmacology and Toxicology, University of Würzburg, 97078 Würzburg, Germany.,ISAR Bioscience Institute, Planegg, 82152 Munich, Germany
| | - Serdar Durdagi
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, 34734 Istanbul, Turkey
| | - Necla Birgul-Iyison
- Department of Molecular Biology and Genetics, Bogazici University, 34342 Istanbul, Turkey
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17
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Bordes L, Chavez-Abiega S, Goedhart J. Imaging of Genetically Encoded FRET-Based Biosensors to Detect GPCR Activity. Methods Mol Biol 2021; 2268:159-178. [PMID: 34085268 DOI: 10.1007/978-1-0716-1221-7_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A wealth of assays for screening GPCR activity have been developed. Biosensors that employ Förster Resonance Energy transfer (FRET) are specific and enable dynamic measurements. Moreover, FRET biosensors are ideally suited for the analysis of single living cells. The FRET biosensors described in this manuscript are entirely genetically encoded by plasmids. Here, protocols for employing FRET-based biosensors to detect G protein activity upon GPCR activation are reported. The protocols include details on the isolation of plasmids, transfection, generation of stable cell lines with the FRET biosensors, FRET ratio imaging, and data analysis.
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Affiliation(s)
- Luca Bordes
- Section Molecular Cytology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Sergei Chavez-Abiega
- Section Molecular Cytology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
- Section Systems Bioinformatics, Amsterdam Institute for Molecules, Medicines and Systems, VU University, Amsterdam, The Netherlands
| | - Joachim Goedhart
- Section Molecular Cytology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
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18
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Bondar A, Lazar J. Optical sensors of heterotrimeric G protein signaling. FEBS J 2020; 288:2570-2584. [DOI: 10.1111/febs.15655] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/26/2020] [Accepted: 12/03/2020] [Indexed: 01/14/2023]
Affiliation(s)
- Alexey Bondar
- Center for Nanobiology and Structural Biology Institute of Microbiology of the Czech Academy of Sciences Nove Hrady Czech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Prague Czech Republic
- Faculty of Science University of South Bohemia Ceske Budejovice Czech Republic
| | - Josef Lazar
- Center for Nanobiology and Structural Biology Institute of Microbiology of the Czech Academy of Sciences Nove Hrady Czech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Prague Czech Republic
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19
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Işbilir A, Duan Sahbaz B, Tuncgenc G, Bünemann M, Lohse MJ, Birgül-Iyison N. Pharmacological Characterization of the Stick Insect Carausius morosus Allatostatin-C Receptor with Its Endogenous Agonist. ACS OMEGA 2020; 5:32183-32194. [PMID: 33376856 PMCID: PMC7758886 DOI: 10.1021/acsomega.0c03382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/04/2020] [Indexed: 05/12/2023]
Abstract
G protein-coupled receptors (GPCRs) play a pivotal role in regulating key physiological events in all animal species. Recent advances in collective analysis of genes and proteins revealed numerous potential neuropeptides and GPCRs from insect species, allowing for the characterization of peptide-receptor pairs. In this work, we used fluorescence resonance energy transfer (FRET)-based genetically encoded biosensors in intact mammalian cells to study the pharmacological features of the cognate GPCR of the type-C allatostatin (AST-C) peptide from the stick insect, Carausius morosus. Analysis of multiple downstream pathways revealed that AST-C can activate the human Gi2 protein, and not Gs or Gq, through AST-C receptor (AlstRC). Activated AlstRC recruits β-arrestin2 independent of the Gi protein but stimulates ERK phosphorylation in a Gi protein-dependent manner. Identification of Gαi-, arrestin-, and GRK-like transcripts from C. morosus revealed high evolutionary conservation at the G protein level, while β-arrestins and GRKs displayed less conservation. In conclusion, our study provides experimental and homology-based evidence on the functionality of vertebrate G proteins and downstream signaling biosensors to characterize early signaling steps of an insect GPCR. These results may serve as a scaffold for developing assays to characterize pharmacological and structural aspects of other insect GPCRs and can be used in deorphanization and pesticide studies.
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Affiliation(s)
- Ali Işbilir
- Department
of Molecular Biology and Genetics, Faculty
of Arts and Sciences, Bogazici University, Istanbul 34342, Turkey
- Max
Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin 13125, Germany
- Institute
of Pharmacology and Toxicology, University
of Würzburg, Würzburg 97078, Germany
| | - Burcin Duan Sahbaz
- Department
of Molecular Biology and Genetics, Faculty
of Arts and Sciences, Bogazici University, Istanbul 34342, Turkey
| | - Gunes Tuncgenc
- Department
of Molecular Biology and Genetics, Faculty
of Arts and Sciences, Bogazici University, Istanbul 34342, Turkey
| | - Moritz Bünemann
- Department
of Pharmacology and Clinical Pharmacy, Philipps-University, Marburg 35043, Germany
| | - Martin J. Lohse
- Max
Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin 13125, Germany
- Institute
of Pharmacology and Toxicology, University
of Würzburg, Würzburg 97078, Germany
- ISAR
Bioscience Institute, Planegg/Munich 82152, Germany
| | - Necla Birgül-Iyison
- Department
of Molecular Biology and Genetics, Faculty
of Arts and Sciences, Bogazici University, Istanbul 34342, Turkey
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20
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Calebiro D, Koszegi Z, Lanoiselée Y, Miljus T, O'Brien S. G protein-coupled receptor-G protein interactions: a single-molecule perspective. Physiol Rev 2020; 101:857-906. [PMID: 33331229 DOI: 10.1152/physrev.00021.2020] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors (GPCRs) regulate many cellular and physiological processes, responding to a diverse range of extracellular stimuli including hormones, neurotransmitters, odorants, and light. Decades of biochemical and pharmacological studies have provided fundamental insights into the mechanisms of GPCR signaling. Thanks to recent advances in structural biology, we now possess an atomistic understanding of receptor activation and G protein coupling. However, how GPCRs and G proteins interact in living cells to confer signaling efficiency and specificity remains insufficiently understood. The development of advanced optical methods, including single-molecule microscopy, has provided the means to study receptors and G proteins in living cells with unprecedented spatio-temporal resolution. The results of these studies reveal an unexpected level of complexity, whereby GPCRs undergo transient interactions among themselves as well as with G proteins and structural elements of the plasma membrane to form short-lived signaling nanodomains that likely confer both rapidity and specificity to GPCR signaling. These findings may provide new strategies to pharmaceutically modulate GPCR function, which might eventually pave the way to innovative drugs for common diseases such as diabetes or heart failure.
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Affiliation(s)
- Davide Calebiro
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Zsombor Koszegi
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Yann Lanoiselée
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Tamara Miljus
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Shannon O'Brien
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
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21
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Liu L, He F, Yu Y, Wang Y. Application of FRET Biosensors in Mechanobiology and Mechanopharmacological Screening. Front Bioeng Biotechnol 2020; 8:595497. [PMID: 33240867 PMCID: PMC7680962 DOI: 10.3389/fbioe.2020.595497] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 10/19/2020] [Indexed: 12/15/2022] Open
Abstract
Extensive studies have shown that cells can sense and modulate the biomechanical properties of the ECM within their resident microenvironment. Thus, targeting the mechanotransduction signaling pathways provides a promising way for disease intervention. However, how cells perceive these mechanical cues of the microenvironment and transduce them into biochemical signals remains to be answered. Förster or fluorescence resonance energy transfer (FRET) based biosensors are a powerful tool that can be used in live-cell mechanotransduction imaging and mechanopharmacological drug screening. In this review, we will first introduce FRET principle and FRET biosensors, and then, recent advances on the integration of FRET biosensors and mechanobiology in normal and pathophysiological conditions will be discussed. Furthermore, we will summarize the current applications and limitations of FRET biosensors in high-throughput drug screening and the future improvement of FRET biosensors. In summary, FRET biosensors have provided a powerful tool for mechanobiology studies to advance our understanding of how cells and matrices interact, and the mechanopharmacological screening for disease intervention.
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Affiliation(s)
| | | | | | - Yingxiao Wang
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA, United States
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22
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Olsen RHJ, DiBerto JF, English JG, Glaudin AM, Krumm BE, Slocum ST, Che T, Gavin AC, McCorvy JD, Roth BL, Strachan RT. TRUPATH, an open-source biosensor platform for interrogating the GPCR transducerome. Nat Chem Biol 2020; 16:841-849. [PMID: 32367019 PMCID: PMC7648517 DOI: 10.1038/s41589-020-0535-8] [Citation(s) in RCA: 263] [Impact Index Per Article: 65.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 03/30/2020] [Indexed: 12/18/2022]
Abstract
G-protein-coupled receptors (GPCRs) remain major drug targets, despite our incomplete understanding of how they signal through 16 non-visual G-protein signal transducers (collectively named the transducerome) to exert their actions. To address this gap, we have developed an open-source suite of 14 optimized bioluminescence resonance energy transfer (BRET) Gαβγ biosensors (named TRUPATH) to interrogate the transducerome with single pathway resolution in cells. Generated through exhaustive protein engineering and empirical testing, the TRUPATH suite of Gαβγ biosensors includes the first Gα15 and GαGustducin probes. In head-to-head studies, TRUPATH biosensors outperformed first-generation sensors at multiple GPCRs and in different cell lines. Benchmarking studies with TRUPATH biosensors recapitulated previously documented signaling bias and revealed new coupling preferences for prototypic and understudied GPCRs with potential in vivo relevance. To enable a greater understanding of GPCR molecular pharmacology by the scientific community, we have made TRUPATH biosensors easily accessible as a kit through Addgene.
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Affiliation(s)
- Reid H J Olsen
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Jeffrey F DiBerto
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Justin G English
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Alexis M Glaudin
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Brian E Krumm
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Samuel T Slocum
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
- National Institute of Mental Health Psychoactive Drug Screening Program, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Tao Che
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Ariana C Gavin
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - John D McCorvy
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA.
- National Institute of Mental Health Psychoactive Drug Screening Program, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA.
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA.
| | - Ryan T Strachan
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA.
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23
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Perpiñá-Viciano C, Işbilir A, Zarca A, Caspar B, Kilpatrick LE, Hill SJ, Smit MJ, Lohse MJ, Hoffmann C. Kinetic Analysis of the Early Signaling Steps of the Human Chemokine Receptor CXCR4. Mol Pharmacol 2020; 98:72-87. [PMID: 32474443 PMCID: PMC7330677 DOI: 10.1124/mol.119.118448] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 05/06/2020] [Indexed: 01/14/2023] Open
Abstract
G protein–coupled receptors (GPCRs) are biologic switches that transduce extracellular stimuli into intracellular responses in the cell. Temporally resolving GPCR transduction pathways is key to understanding how cell signaling occurs. Here, we investigate the kinetics and dynamics of the activation and early signaling steps of the CXC chemokine receptor (CXCR) 4 in response to its natural ligands CXC chemokine ligand (CXCL) 12 and macrophage migration inhibitory factor (MIF), using Förster resonance energy transfer–based approaches. We show that CXCR4 presents a multifaceted response to CXCL12, with receptor activation (≈0.6 seconds) followed by a rearrangement in the receptor/G protein complex (≈1 seconds), a slower dimer rearrangement (≈1.7 seconds), and prolonged G protein activation (≈4 seconds). In comparison, MIF distinctly modulates every step of the transduction pathway, indicating distinct activation mechanisms and reflecting the different pharmacological properties of these two ligands. Our study also indicates that CXCR4 exhibits some degree of ligand-independent activity, a relevant feature for drug development.
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Affiliation(s)
- Cristina Perpiñá-Viciano
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Ali Işbilir
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Aurélien Zarca
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Birgit Caspar
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Laura E Kilpatrick
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Stephen J Hill
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Martine J Smit
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Martin J Lohse
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
| | - Carsten Hoffmann
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine (CMB), University Hospital Jena, University of Jena, Jena, Germany (C.P.-V., C.H.); Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany (C.P.-V., A.I., M.J.L., C.H.); Max-Delbrück Center for Molecular Medicine, Berlin, Germany (A.I., M.J.L.); Amsterdam Institute for Molecules Medicines and Systems (AIMMS), Division of Medicinal Chemistry, Vrije Universiteit, Amsterdam, The Netherlands (A.Z., M.J.S.); Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, United Kingdom (B.C., L.E.K., S.J.H.); and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, United Kingdom (B.C., L.E.K., S.J.H.)
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24
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Zuconelli CR, Schmidt S, Wallbrecher R, van Oostrum J, Bartels YL, Didan Y, Berendsen ML, Brock R, Adjobo-Hermans MJ. Modulation of Orai1 by cationic peptides triggers their direct cytosolic uptake. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183155. [DOI: 10.1016/j.bbamem.2019.183155] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 11/29/2019] [Accepted: 12/10/2019] [Indexed: 02/07/2023]
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Pietraszewska-Bogiel A, Joosen L, Chertkova AO, Goedhart J. Not So Dry After All: DRY Mutants of the AT1 A Receptor and H1 Receptor Can Induce G-Protein-Dependent Signaling. ACS OMEGA 2020; 5:2648-2659. [PMID: 32095688 PMCID: PMC7033670 DOI: 10.1021/acsomega.9b03146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
G-protein-coupled receptors (GPCRs) are seven transmembrane spanning receptors that regulate a wide array of intracellular signaling cascades in response to various stimuli. To do so, they couple to different heterotrimeric G proteins and adaptor proteins, including arrestins. Importantly, arrestins were shown to regulate GPCR signaling through G proteins, as well as promote G protein-independent signaling events. Several research groups have reported successful isolation of exclusively G protein-dependent and arrestin-dependent signaling downstream of GPCR activation using biased agonists or receptor mutants incapable of coupling to either arrestins or G proteins. In the latter category, the DRY mutant of the angiotensin II type 1 receptor was extensively used to characterize the functional selectivity downstream of AT1AR. In an attempt to understand histamine 1 receptor signaling, we characterized the signaling capacity of the H1R DRY mutant in a panel of dynamic, live cell biosensor assays, including arrestin recruitment, heterotrimeric G protein activation, Ca2+ signaling, protein kinase C activity, GTP binding of RhoA, and activation of ERK1/2. Here, we show that both H1R DRY mutant and the AT1AR DRY mutant are capable of efficient activation of G protein-mediated signaling. Therefore, contrary to the common belief, they do not constitute suitable tools for the dissection of the arrestin-mediated, G protein-independent signaling downstream of these receptors.
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Sensing Extracellular Calcium - An Insight into the Structure and Function of the Calcium-Sensing Receptor (CaSR). ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:1031-1063. [PMID: 31646544 DOI: 10.1007/978-3-030-12457-1_41] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The calcium-sensing receptor (CaSR) is a G protein-coupled receptor that plays a key role in calcium homeostasis, by sensing free calcium levels in blood and regulating parathyroid hormone secretion in response. The CaSR is highly expressed in parathyroid gland and kidney where its role is well characterised, but also in other tissues where its function remains to be determined. The CaSR can be activated by a variety of endogenous ligands, as well as by synthetic modulators such as Cinacalcet, used in the clinic to treat secondary hyperparathyroidism in patients with chronic kidney disease. The CaSR couples to multiple G proteins, in a tissue-specific manner, activating several signalling pathways and thus regulating diverse intracellular events. The multifaceted nature of this receptor makes it a valuable therapeutic target for calciotropic and non-calciotropic diseases. It is therefore essential to understand the complexity behind the pharmacology, trafficking, and signalling characteristics of this receptor. This review provides an overview of the latest knowledge about the CaSR and discusses future hot topics in this field.
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Helix 8 is the essential structural motif of mechanosensitive GPCRs. Nat Commun 2019; 10:5784. [PMID: 31857598 PMCID: PMC6923424 DOI: 10.1038/s41467-019-13722-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 11/19/2019] [Indexed: 12/16/2022] Open
Abstract
G-protein coupled receptors (GPCRs) are versatile cellular sensors for chemical stimuli, but also serve as mechanosensors involved in various (patho)physiological settings like vascular regulation, cardiac hypertrophy and preeclampsia. However, the molecular mechanisms underlying mechanically induced GPCR activation have remained elusive. Here we show that mechanosensitive histamine H1 receptors (H1Rs) are endothelial sensors of fluid shear stress and contribute to flow-induced vasodilation. At the molecular level, we observe that H1Rs undergo stimulus-specific patterns of conformational changes suggesting that mechanical forces and agonists induce distinct active receptor conformations. GPCRs lacking C-terminal helix 8 (H8) are not mechanosensitive, and transfer of H8 to non-responsive GPCRs confers, while removal of H8 precludes, mechanosensitivity. Moreover, disrupting H8 structural integrity by amino acid exchanges impairs mechanosensitivity. Altogether, H8 is the essential structural motif endowing GPCRs with mechanosensitivity. These findings provide a mechanistic basis for a better understanding of the roles of mechanosensitive GPCRs in (patho)physiology. GPCRs are versatile cellular sensors for chemical stimuli but the molecular mechanisms underlying mechanically induced GPCR activation have remained elusive. Here authors identify the C-terminal helix 8 (H8) as the essential structural motif endowing H1R and other GPCRs with mechanosensitivity.
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Plach M, Schäfer T, Borroto-Escuela DO, Weikert D, Gmeiner P, Fuxe K, Friedland K. Differential allosteric modulation within dopamine D 2R - neurotensin NTS1R and D 2R - serotonin 5-HT 2AR receptor complexes gives bias to intracellular calcium signalling. Sci Rep 2019; 9:16312. [PMID: 31704949 PMCID: PMC6841725 DOI: 10.1038/s41598-019-52540-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/15/2019] [Indexed: 12/11/2022] Open
Abstract
Proceeding investigations of G protein-coupled receptor (GPCR) heterocomplexes have demonstrated that the dopamine D2 receptor (D2R), one of the hub receptors in the physiology of schizophrenia, interacts with both the neurotensin NTS1 (NTS1R) and the serotonin 5-HT2A receptor (5-HT2AR) in cell lines and rodent brain tissue. In situ proximity ligation assay and BRET-based saturation experiments confirmed interacting receptor assemblies in HEK293T and neuronal HT22 cells. The NTS1R agonist NT(8-13) reduces the Gαq-mediated calcium signal in the NTS1R-D2R complex compared to the NTS1R monomer which could be reversed by D2R antagonists. The bivalent ligand CS148 (NTS1R-agonistic, D2R-antagonistic) increased the calcium response addressing the dimer, consistent with the effect of the monovalent ligands suggesting an allosteric D2R-mediated modulation. In contrast, the 5-HT2AR-D2R heteromer did not show a calcium-altering receptor-receptor interaction. Despite their common coupling-preference for Gαq, 5-HT2AR and NTS1R supposedly interact with D2R each in a unique mode. This remarkably diverse ligand-mediated signalling in two different D2R heteroreceptor complexes illustrates the complexity of receptor-receptor interactions and their potential of modifying cell responses to external stimuli. Therefore, GPCR heteromers may provide a very promising novel target for the therapy of neuropsychiatric disorders.
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Affiliation(s)
- Michael Plach
- Department of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Thorsten Schäfer
- Department of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | | | - Dorothée Weikert
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Kristina Friedland
- Department of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany. .,Pharmacology and Toxicology, Institute of Pharmacy and Biochemistry, Johannes-Gutenberg-Universität, Mainz, Germany.
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29
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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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30
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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 DOI: 10.1021/acs.chemrev.8b00333] [Citation(s) in RCA: 295] [Impact Index Per Article: 49.2] [Reference Citation Analysis] [Abstract] [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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31
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Wright SC, Cañizal MCA, Benkel T, Simon K, Le Gouill C, Matricon P, Namkung Y, Lukasheva V, König GM, Laporte SA, Carlsson J, Kostenis E, Bouvier M, Schulte G, Hoffmann C. FZD 5 is a Gα q-coupled receptor that exhibits the functional hallmarks of prototypical GPCRs. Sci Signal 2018; 11:11/559/eaar5536. [PMID: 30514810 DOI: 10.1126/scisignal.aar5536] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Frizzleds (FZDs) are a group of seven transmembrane-spanning (7TM) receptors that belong to class F of the G protein-coupled receptor (GPCR) superfamily. FZDs bind WNT proteins to stimulate diverse signaling cascades involved in embryonic development, stem cell regulation, and adult tissue homeostasis. Frizzled 5 (FZD5) is one of the most studied class F GPCRs that promote the functional inactivation of the β-catenin destruction complex in response to WNTs. However, whether FZDs function as prototypical GPCRs has been heavily debated and, in particular, FZD5 has not been shown to activate heterotrimeric G proteins. Here, we show that FZD5 exhibited a conformational change after the addition of WNT-5A, which is reminiscent of class A and class B GPCR activation. In addition, we performed several live-cell imaging and spectrometric-based approaches, such as dual-color fluorescence recovery after photobleaching (dcFRAP) and resonance energy transfer (RET)-based assays that demonstrated that FZD5 activated Gαq and its downstream effectors upon stimulation with WNT-5A. Together, these findings suggest that FZD5 is a 7TM receptor with a bona fide GPCR activation profile and suggest novel targets for drug discovery in WNT-FZD signaling.
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Affiliation(s)
- Shane C Wright
- Section of Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, S17165 Stockholm, Sweden.,Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montréal, Montréal, QC H3C 3J7, Canada
| | - Maria Consuelo Alonso Cañizal
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany.,Institute for Molecular Cell Biology, CMB-Center for Molecular Biomedicine, University Hospital Jena, Friedrich-Schiller University Jena, Hans-Knöll-Strasse 2, 07745 Jena, Germany
| | - Tobias Benkel
- Institute for Pharmaceutical Biology, University of Bonn, 53115 Bonn, Germany
| | - Katharina Simon
- Institute for Pharmaceutical Biology, University of Bonn, 53115 Bonn, Germany
| | - Christian Le Gouill
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montréal, Montréal, QC H3C 3J7, Canada
| | - Pierre Matricon
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden
| | - Yoon Namkung
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montréal, QC H4A 3J1, Canada
| | - Viktoria Lukasheva
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montréal, Montréal, QC H3C 3J7, Canada
| | - Gabriele M König
- Institute for Pharmaceutical Biology, University of Bonn, 53115 Bonn, Germany
| | - Stéphane A Laporte
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montréal, QC H4A 3J1, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada
| | - Jens Carlsson
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden
| | - Evi Kostenis
- Institute for Pharmaceutical Biology, University of Bonn, 53115 Bonn, Germany
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montréal, Montréal, QC H3C 3J7, Canada
| | - Gunnar Schulte
- Section of Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, S17165 Stockholm, Sweden.
| | - Carsten Hoffmann
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany. .,Institute for Molecular Cell Biology, CMB-Center for Molecular Biomedicine, University Hospital Jena, Friedrich-Schiller University Jena, Hans-Knöll-Strasse 2, 07745 Jena, Germany
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32
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O'Brien SL, Johnstone EKM, Devost D, Conroy J, Reichelt ME, Purdue BW, Ayoub MA, Kawai T, Inoue A, Eguchi S, Hébert TE, Pfleger KDG, Thomas WG. BRET-based assay to monitor EGFR transactivation by the AT 1R reveals G q/11 protein-independent activation and AT 1R-EGFR complexes. Biochem Pharmacol 2018; 158:232-242. [PMID: 30347205 DOI: 10.1016/j.bcp.2018.10.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 10/17/2018] [Indexed: 01/09/2023]
Abstract
The type 1 angiotensin II (AngII) receptor (AT1R) transactivates the epidermal growth factor receptor (EGFR), which leads to pathological remodeling of heart, blood vessels and kidney. End-point assays are used as surrogates of EGFR activation, however these downstream readouts are not applicable to live cells, in real-time. Herein, we report the use of a bioluminescence resonance energy transfer (BRET)-based assay to assess recruitment of the EGFR adaptor protein, growth factor receptor-bound protein 2 (Grb2), to the EGFR. In a variety of cell lines, both epidermal growth factor (EGF) and AngII stimulated Grb2 recruitment to EGFR. The BRET assay was used to screen a panel of 9 G protein-coupled receptors (GPCRs) and further developed for other EGFR family members (HER2 and HER3); the AT1R was able to transactivate HER2, but not HER3. Mechanistically, AT1R-mediated ERK1/2 activation was dependent on Gq/11 and EGFR tyrosine kinase activity, whereas the recruitment of Grb2 to the EGFR was independent of Gq/11 and only partially dependent on EGFR tyrosine kinase activity. This Gq/11 independence of EGFR transactivation was confirmed using AT1R mutants and in CRISPR cell lines lacking Gq/11. EGFR transactivation was also apparently independent of β-arrestins. Finally, we used additional BRET-based assays and confocal microscopy to provide evidence that both AngII- and EGF-stimulation promoted AT1R-EGFR heteromerization. In summary, we report an alternative approach to monitoring AT1R-EGFR transactivation in live cells, which provides a more direct and proximal view of this process, including the potential for complexes between the AT1R and EGFR.
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Affiliation(s)
- Shannon L O'Brien
- Receptor Biology Group, The School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Elizabeth K M Johnstone
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Dominic Devost
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Jacinta Conroy
- Receptor Biology Group, The School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Melissa E Reichelt
- Receptor Biology Group, The School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Brooke W Purdue
- Receptor Biology Group, The School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Mohammed A Ayoub
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Tatsuo Kawai
- Cardiovascular Research Centre, Department of Physiology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Satoru Eguchi
- Cardiovascular Research Centre, Department of Physiology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Kevin D G Pfleger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia 6009, Australia; Dimerix Limited, Nedlands, Western Australia 6009, Australia
| | - Walter G Thomas
- Receptor Biology Group, The School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia 4072, Queensland, Australia; Centre for Cardiac and Vasculature Biology, The University of Queensland, St Lucia 4072, Queensland, Australia.
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33
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Spahn V, Del Vecchio G, Rodriguez-Gaztelumendi A, Temp J, Labuz D, Kloner M, Reidelbach M, Machelska H, Weber M, Stein C. Opioid receptor signaling, analgesic and side effects induced by a computationally designed pH-dependent agonist. Sci Rep 2018; 8:8965. [PMID: 29895890 PMCID: PMC5997768 DOI: 10.1038/s41598-018-27313-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 05/31/2018] [Indexed: 12/26/2022] Open
Abstract
Novel pain killers without adverse effects are urgently needed. Opioids induce central and intestinal side effects such as respiratory depression, sedation, addiction, and constipation. We have recently shown that a newly designed agonist with a reduced acid dissociation constant (pKa) abolished pain by selectively activating peripheral μ-opioid receptors (MOR) in inflamed (acidic) tissues without eliciting side effects. Here, we extended this concept in that pKa reduction to 7.22 was achieved by placing a fluorine atom at the ethylidene bridge in the parental molecule fentanyl. The new compound (FF3) showed pH-sensitive MOR affinity, [35S]-GTPγS binding, and G protein dissociation by fluorescence resonance energy transfer. It produced injury-restricted analgesia in rat models of inflammatory, postoperative, abdominal, and neuropathic pain. At high dosages, FF3 induced sedation, motor disturbance, reward, constipation, and respiratory depression. These results support our hypothesis that a ligand’s pKa should be close to the pH of injured tissue to obtain analgesia without side effects.
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Affiliation(s)
- Viola Spahn
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Giovanna Del Vecchio
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Antonio Rodriguez-Gaztelumendi
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.,Department of Drug Discovery and In Vitro Pharmacology, Laboratorios Dr. Esteve, Parc Científic de Barcelona, Barcelona, Spain
| | - Julia Temp
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Dominika Labuz
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Michael Kloner
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Marco Reidelbach
- Freie Universität Berlin, Institute of Theoretical Physics, Arnimallee 14, 14195, Berlin, Germany
| | - Halina Machelska
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Marcus Weber
- Zuse Institute Berlin, Computational Molecular Design, Takustraße 7, 14195, Berlin, Germany
| | - Christoph Stein
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
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Liu Y, Chen LY, Zeng H, Ward R, Wu N, Ma L, Mu X, Li QL, Yang Y, An S, Guo XX, Hao Q, Xu TR. Assessing the real-time activation of the cannabinoid CB1 receptor and the associated structural changes using a FRET biosensor. Int J Biochem Cell Biol 2018; 99:114-124. [PMID: 29626639 DOI: 10.1016/j.biocel.2018.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/25/2018] [Accepted: 04/04/2018] [Indexed: 11/18/2022]
Abstract
The cannabinoid receptor 1 (CB1) is mainly expressed in the nervous system and regulates learning, memory processes, pain and energy metabolism. However, there is no way to directly measure its activation. In this study, we constructed a CB1 intramolecular fluorescence resonance energy transfer (FRET) sensor, which could measure CB1 activation by monitoring structural changes between the third intracellular loop and the C-terminal tail. CB1 agonists induced a time- and concentration-dependent increase in the FRET signal, corresponding to a reduction in the distance between the third intracellular loop and the C-terminal tail. This, in turn, mobilized intracellular Ca2+, inhibited cAMP accumulation, and increased phosphorylation of the ERK1/2 MAP kinases. The activation kinetics detected using this method were consistent with those from previous reports. Moreover, the increased FRET signal was markedly inhibited by the CB1 antagonist rimonabant, which also reduced phosphorylation of the ERK1/2 MAP kinases. We mutated a single cysteine residue in the sensor (at position 257 or 264) to alanine. Both mutation reduced the agonist-induced increase in FRET signal and structural changes in the CB1 receptor, which attenuated phosphorylation of the ERK1/2 MAP kinases. In summary, our sensor directly assesses the kinetics of CB1 activation in real-time and can be used to monitor CB1 structure and function.
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Affiliation(s)
- Ying Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Lu-Yao Chen
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Hong Zeng
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Richard Ward
- Center for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Nan Wu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Li Ma
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Xi Mu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Qiu-Lan Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Yang Yang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Su An
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Xiao-Xi Guo
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Qian Hao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Tian-Rui Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China.
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35
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Mastop M, Reinhard NR, Zuconelli CR, Terwey F, Gadella TWJ, van Unen J, Adjobo-Hermans MJW, Goedhart J. A FRET-based biosensor for measuring Gα13 activation in single cells. PLoS One 2018; 13:e0193705. [PMID: 29505611 PMCID: PMC5837189 DOI: 10.1371/journal.pone.0193705] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/19/2018] [Indexed: 12/22/2022] Open
Abstract
Förster Resonance Energy Transfer (FRET) provides a way to directly observe the activation of heterotrimeric G-proteins by G-protein coupled receptors (GPCRs). To this end, FRET based biosensors are made, employing heterotrimeric G-protein subunits tagged with fluorescent proteins. These FRET based biosensors complement existing, indirect, ways to observe GPCR activation. Here we report on the insertion of mTurquoise2 at several sites in the human Gα13 subunit, aiming to develop a FRET-based Gα13 activation biosensor. Three fluorescently tagged Gα13 variants were found to be functional based on i) plasma membrane localization and ii) ability to recruit p115-RhoGEF upon activation of the LPA2 receptor. The tagged Gα13 subunits were used as FRET donor and combined with cp173Venus fused to the Gγ2 subunit, as the acceptor. We constructed Gα13 biosensors by generating a single plasmid that produces Gα13-mTurquoise2, Gβ1 and cp173Venus-Gγ2. The Gα13 activation biosensors showed a rapid and robust response when used in primary human endothelial cells that were exposed to thrombin, triggering endogenous protease activated receptors (PARs). This response was efficiently inhibited by the RGS domain of p115-RhoGEF and from the biosensor data we inferred that this is due to GAP activity. Finally, we demonstrated that the Gα13 sensor can be used to dissect heterotrimeric G-protein coupling efficiency in single living cells. We conclude that the Gα13 biosensor is a valuable tool for live-cell measurements that probe spatiotemporal aspects of Gα13 activation.
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Affiliation(s)
- Marieke Mastop
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Nathalie R. Reinhard
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Cristiane R. Zuconelli
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Fenna Terwey
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Theodorus W. J. Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Jakobus van Unen
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Merel J. W. Adjobo-Hermans
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
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36
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Long Y, Stahl Y, Weidtkamp-Peters S, Smet W, Du Y, Gadella TWJ, Goedhart J, Scheres B, Blilou I. Optimizing FRET-FLIM Labeling Conditions to Detect Nuclear Protein Interactions at Native Expression Levels in Living Arabidopsis Roots. FRONTIERS IN PLANT SCIENCE 2018; 9:639. [PMID: 29868092 PMCID: PMC5962846 DOI: 10.3389/fpls.2018.00639] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 04/25/2018] [Indexed: 05/21/2023]
Abstract
Protein complex formation has been extensively studied using Förster resonance energy transfer (FRET) measured by Fluorescence Lifetime Imaging Microscopy (FLIM). However, implementing this technology to detect protein interactions in living multicellular organism at single-cell resolution and under native condition is still difficult to achieve. Here we describe the optimization of the labeling conditions to detect FRET-FLIM in living plants. This study exemplifies optimization procedure involving the identification of the optimal position for the labels either at the N or C terminal region and the selection of the bright and suitable, fluorescent proteins as donor and acceptor labels for the FRET study. With an effective optimization strategy, we were able to detect the interaction between the stem cell regulators SHORT-ROOT and SCARECROW at endogenous expression levels in the root pole of living Arabidopsis embryos and developing lateral roots by FRET-FLIM. Using this approach we show that the spatial profile of interaction between two transcription factors can be highly modulated in reoccurring and structurally resembling organs, thus providing new information on the dynamic redistribution of nuclear protein complex configurations in different developmental stages. In principle, our optimization procedure for transcription factor complexes is applicable to any biological system.
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Affiliation(s)
- Yuchen Long
- Plant Developmental Biology, Wageningen University and Research Centre, Wageningen, Netherlands
| | - Yvonne Stahl
- Institute for Developmental Genetics, Heinrich Heine University, Düsseldorf, Germany
| | | | - Wouter Smet
- Plant Developmental Biology, Wageningen University and Research Centre, Wageningen, Netherlands
| | - Yujuan Du
- Plant Developmental Biology, Wageningen University and Research Centre, Wageningen, Netherlands
| | - Theodorus W. J. Gadella
- Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Joachim Goedhart
- Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Ben Scheres
- Plant Developmental Biology, Wageningen University and Research Centre, Wageningen, Netherlands
| | - Ikram Blilou
- Plant Developmental Biology, Wageningen University and Research Centre, Wageningen, Netherlands
- Plant Cell and Developmental Biology, King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering (BESE), Thuwal, Saudi Arabia
- *Correspondence: Ikram Blilou
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37
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Spahn V, Del Vecchio G, Labuz D, Rodriguez-Gaztelumendi A, Massaly N, Temp J, Durmaz V, Sabri P, Reidelbach M, Machelska H, Weber M, Stein C. A nontoxic pain killer designed by modeling of pathological receptor conformations. Science 2017; 355:966-969. [PMID: 28254944 DOI: 10.1126/science.aai8636] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/30/2017] [Indexed: 12/12/2022]
Abstract
Indiscriminate activation of opioid receptors provides pain relief but also severe central and intestinal side effects. We hypothesized that exploiting pathological (rather than physiological) conformation dynamics of opioid receptor-ligand interactions might yield ligands without adverse actions. By computer simulations at low pH, a hallmark of injured tissue, we designed an agonist that, because of its low acid dissociation constant, selectively activates peripheral μ-opioid receptors at the source of pain generation. Unlike the conventional opioid fentanyl, this agonist showed pH-sensitive binding, heterotrimeric guanine nucleotide-binding protein (G protein) subunit dissociation by fluorescence resonance energy transfer, and adenosine 3',5'-monophosphate inhibition in vitro. It produced injury-restricted analgesia in rats with different types of inflammatory pain without exhibiting respiratory depression, sedation, constipation, or addiction potential.
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Affiliation(s)
- V Spahn
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - G Del Vecchio
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - D Labuz
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - A Rodriguez-Gaztelumendi
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - N Massaly
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - J Temp
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - V Durmaz
- Computational Molecular Design, Zuse-Institut Berlin, Takustrasse 7, Berlin, 14195, Germany
| | - P Sabri
- Computational Molecular Design, Zuse-Institut Berlin, Takustrasse 7, Berlin, 14195, Germany
| | - M Reidelbach
- Computational Molecular Design, Zuse-Institut Berlin, Takustrasse 7, Berlin, 14195, Germany
| | - H Machelska
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany
| | - M Weber
- Computational Molecular Design, Zuse-Institut Berlin, Takustrasse 7, Berlin, 14195, Germany
| | - C Stein
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin Campus Benjamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, Berlin 12203, Germany.
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38
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Mastop M, Bindels DS, Shaner NC, Postma M, Gadella TWJ, Goedhart J. Characterization of a spectrally diverse set of fluorescent proteins as FRET acceptors for mTurquoise2. Sci Rep 2017; 7:11999. [PMID: 28931898 PMCID: PMC5607329 DOI: 10.1038/s41598-017-12212-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 09/05/2017] [Indexed: 01/13/2023] Open
Abstract
The performance of Förster Resonance Energy Transfer (FRET) biosensors depends on brightness and photostability, which are dependent on the characteristics of the fluorescent proteins that are employed. Yellow fluorescent protein (YFP) is often used as an acceptor but YFP is prone to photobleaching and pH changes. In this study, we evaluated the properties of a diverse set of acceptor fluorescent proteins in combination with the optimized CFP variant mTurquoise2 as the donor. To determine the theoretical performance of acceptors, the Förster radius was determined. The practical performance was determined by measuring FRET efficiency and photostability of tandem fusion proteins in mammalian cells. Our results show that mNeonGreen is the most efficient acceptor for mTurquoise2 and that the photostability is better than SYFP2. The non-fluorescent YFP variant sREACh is an efficient acceptor, which is useful in lifetime-based FRET experiments. Among the orange and red fluorescent proteins, mCherry and mScarlet-I are the best performing acceptors. Several new pairs were applied in a multimolecular FRET based sensor for detecting activation of a heterotrimeric G-protein by G-protein coupled receptors. Overall, the sensor with mNeonGreen as acceptor and mTurquoise2 as donor showed the highest dynamic range in ratiometric FRET imaging experiments with the G-protein sensor.
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Affiliation(s)
- Marieke Mastop
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Daphne S Bindels
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Nathan C Shaner
- Department of Photobiology and Bioimaging, The Scintillon Institute, San Diego, California, United States of America
| | - Marten Postma
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Theodorus W J Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands.
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39
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Agnetta L, Kauk M, Canizal MCA, Messerer R, Holzgrabe U, Hoffmann C, Decker M. Ein photoschaltbarer Ligand zur Regulierung der Rezeptoraktivierung. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701524] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Luca Agnetta
- Pharmazeutische und Medizinische Chemie; Institut für Pharmazie und Lebensmittelchemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Michael Kauk
- Pharmakologie und Toxikologie; Julius-Maximilians-Universität Würzburg; Versbacher Str. 9 97078 Würzburg Deutschland
- Rudolf Virchow Zentrum für Experimentelle Biomedizin; Julius-Maximilians-Universität Würzburg; Josef-Schneider-Str. 2 97080 Würzburg Deutschland
| | - Maria Consuelo Alonso Canizal
- Pharmakologie und Toxikologie; Julius-Maximilians-Universität Würzburg; Versbacher Str. 9 97078 Würzburg Deutschland
- Rudolf Virchow Zentrum für Experimentelle Biomedizin; Julius-Maximilians-Universität Würzburg; Josef-Schneider-Str. 2 97080 Würzburg Deutschland
| | - Regina Messerer
- Pharmazeutische und Medizinische Chemie; Institut für Pharmazie und Lebensmittelchemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Ulrike Holzgrabe
- Pharmazeutische und Medizinische Chemie; Institut für Pharmazie und Lebensmittelchemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Carsten Hoffmann
- Pharmakologie und Toxikologie; Julius-Maximilians-Universität Würzburg; Versbacher Str. 9 97078 Würzburg Deutschland
- Rudolf Virchow Zentrum für Experimentelle Biomedizin; Julius-Maximilians-Universität Würzburg; Josef-Schneider-Str. 2 97080 Würzburg Deutschland
- Institut für Molekulare Zellbiologie, CMB - Zentrum für Molekulare Biomedizin; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena; Hans-Knöll-Str. 2 07745 Jena Deutschland
| | - Michael Decker
- Pharmazeutische und Medizinische Chemie; Institut für Pharmazie und Lebensmittelchemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
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40
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Agnetta L, Kauk M, Canizal MCA, Messerer R, Holzgrabe U, Hoffmann C, Decker M. A Photoswitchable Dualsteric Ligand Controlling Receptor Efficacy. Angew Chem Int Ed Engl 2017; 56:7282-7287. [DOI: 10.1002/anie.201701524] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 03/30/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Luca Agnetta
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University of Würzburg; Am Hubland 97074 Würzburg Germany
| | - Michael Kauk
- Department of Pharmacology and Toxicology; Julius Maximilian University of Würzburg; Versbacher Strasse 9 97078 Würzburg Germany
- Rudolf Virchow Center for Experimental Biomedicine; Julius Maximilian University of Würzburg; Josef Schneider Strasse 2 97080 Würzburg Germany
| | - Maria Consuelo Alonso Canizal
- Department of Pharmacology and Toxicology; Julius Maximilian University of Würzburg; Versbacher Strasse 9 97078 Würzburg Germany
- Rudolf Virchow Center for Experimental Biomedicine; Julius Maximilian University of Würzburg; Josef Schneider Strasse 2 97080 Würzburg Germany
| | - Regina Messerer
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University of Würzburg; Am Hubland 97074 Würzburg Germany
| | - Ulrike Holzgrabe
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University of Würzburg; Am Hubland 97074 Würzburg Germany
| | - Carsten Hoffmann
- Department of Pharmacology and Toxicology; Julius Maximilian University of Würzburg; Versbacher Strasse 9 97078 Würzburg Germany
- Rudolf Virchow Center for Experimental Biomedicine; Julius Maximilian University of Würzburg; Josef Schneider Strasse 2 97080 Würzburg Germany
- Current address: Institute for Molecular Cell Biology; CMB-Center for Molecular Biomedicine; University Hospital Jena, Friedrich Schiller University Jena; Hans-Knöll-Strasse 2 07745 Jena Germany
| | - Michael Decker
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University of Würzburg; Am Hubland 97074 Würzburg Germany
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41
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Stern E, Ruf-Zamojski F, Zalepa-King L, Pincas H, Choi SG, Peskin CS, Hayot F, Turgeon JL, Sealfon SC. Modeling and high-throughput experimental data uncover the mechanisms underlying Fshb gene sensitivity to gonadotropin-releasing hormone pulse frequency. J Biol Chem 2017; 292:9815-9829. [PMID: 28385888 DOI: 10.1074/jbc.m117.783886] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/06/2017] [Indexed: 11/06/2022] Open
Abstract
Neuroendocrine control of reproduction by brain-secreted pulses of gonadotropin-releasing hormone (GnRH) represents a longstanding puzzle about extracellular signal decoding mechanisms. GnRH regulates the pituitary gonadotropin's follicle-stimulating hormone (FSH) and luteinizing hormone (LH), both of which are heterodimers specified by unique β subunits (FSHβ/LHβ). Contrary to Lhb, Fshb gene induction has a preference for low-frequency GnRH pulses. To clarify the underlying regulatory mechanisms, we developed three biologically anchored mathematical models: 1) parallel activation of Fshb inhibitory factors (e.g. inhibin α and VGF nerve growth factor-inducible), 2) activation of a signaling component with a refractory period (e.g. G protein), and 3) inactivation of a factor needed for Fshb induction (e.g. growth differentiation factor 9). Simulations with all three models recapitulated the Fshb expression levels obtained in pituitary gonadotrope cells perifused with varying GnRH pulse frequencies. Notably, simulations altering average concentration, pulse duration, and pulse frequency revealed that the apparent frequency-dependent pattern of Fshb expression in model 1 actually resulted from variations in average GnRH concentration. In contrast, models 2 and 3 showed "true" pulse frequency sensing. To resolve which components of this GnRH signal induce Fshb, we developed a high-throughput parallel experimental system. We analyzed over 4,000 samples in experiments with varying near-physiological GnRH concentrations and pulse patterns. Whereas Egr1 and Fos genes responded only to variations in average GnRH concentration, Fshb levels were sensitive to both average concentration and true pulse frequency. These results provide a foundation for understanding the role of multiple regulatory factors in modulating Fshb gene activity.
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Affiliation(s)
| | | | | | | | | | - Charles S Peskin
- the Courant Institute of Mathematical Sciences and Center for Neural Science, New York University, New York, New York 10012, and
| | | | - Judith L Turgeon
- the Division of Endocrinology, Department of Internal Medicine, School of Medicine, University of California, Davis, California 95616
| | - Stuart C Sealfon
- From the Department of Neurology and .,the Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York 10029
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42
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Kinetics of recruitment and allosteric activation of ARHGEF25 isoforms by the heterotrimeric G-protein Gαq. Sci Rep 2016; 6:36825. [PMID: 27833100 PMCID: PMC5105084 DOI: 10.1038/srep36825] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 10/17/2016] [Indexed: 02/06/2023] Open
Abstract
Rho GTPases are master regulators of the eukaryotic cytoskeleton. The activation of Rho GTPases is governed by Rho guanine nucleotide exchange factors (GEFs). Three RhoGEF isoforms are produced by the gene ARHGEF25; p63RhoGEF580, GEFT and a recently discovered longer isoform of 619 amino acids (p63RhoGEF619). The subcellular distribution of p63RhoGEF580 and p63RhoGEF619 is strikingly different in unstimulated cells, p63RhoGEF580 is located at the plasma membrane and p63RhoGEF619 is confined to the cytoplasm. Interestingly, we find that both P63RhoGEF580 and p63RhoGEF619 activate RhoGTPases to a similar extent after stimulation of Gαq coupled GPCRs. Furthermore, we show that p63RhoGEF619 relocates to the plasma membrane upon activation of Gαq coupled GPCRs, resembling the well-known activation mechanism of RhoGEFs activated by Gα12/13. Synthetic recruitment of p63RhoGEF619 to the plasma membrane increases RhoGEF activity towards RhoA, but full activation requires allosteric activation via Gαq. Together, these findings reveal a dual role for Gαq in RhoGEF activation, as it both recruits and allosterically activates cytosolic ARHGEF25 isoforms.
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43
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Lieb S, Littmann T, Plank N, Felixberger J, Tanaka M, Schäfer T, Krief S, Elz S, Friedland K, Bernhardt G, Wegener J, Ozawa T, Buschauer A. Label-free versus conventional cellular assays: Functional investigations on the human histamine H 1 receptor. Pharmacol Res 2016; 114:13-26. [PMID: 27751876 DOI: 10.1016/j.phrs.2016.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 10/11/2016] [Accepted: 10/11/2016] [Indexed: 01/07/2023]
Abstract
A set of histamine H1 receptor (H1R) agonists and antagonists was characterized in functional assays, using dynamic mass redistribution (DMR), electric cell-substrate impedance sensing (ECIS) and various signaling pathway specific readouts (Fura-2 and aequorin calcium assays, arrestin recruitment (luciferase fragment complementation) assay, luciferase gene reporter assay). Data were gained from genetically engineered HEK293T cells and compared with reference data from GTPase assays and radioligand binding. Histamine and the other H1R agonists gave different assay-related pEC50 values, however, the order of potency was maintained. In the luciferase fragment complementation assay, the H1R preferred β-arrestin2 over β-arrestin1. The calcium and the impedimetric assay depended on Gq coupling of the H1R, as demonstrated by complete inhibition of the histamine-induced signals in the presence of the Gq inhibitor FR900359 (UBO-QIC). Whereas partial inhibition by FR900359 was observed in DMR and the gene reporter assay, pertussis toxin substantially decreased the response in DMR, but increased the luciferase signal, reflecting the contribution of both, Gq and Gi, to signaling in these assays. For antagonists, the results from DMR were essentially compatible with those from conventional readouts, whereas the impedance-based data revealed a trend towards higher pKb values. ECIS and calcium assays apparently only reflect Gq signaling, whereas DMR and gene reporter assays appear to integrate both, Gq and Gi mediated signaling. The results confirm the value of the label-free methods, DMR and ECIS, for the characterization of H1R ligands. Both noninvasive techniques are complementary to each other, but cannot fully replace reductionist signaling pathway focused assays.
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Affiliation(s)
- S Lieb
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - T Littmann
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - N Plank
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - J Felixberger
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - M Tanaka
- Department of Chemistry, School of Science, University of Tokyo, Tokyo, Japan
| | - T Schäfer
- Department of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander Universität Erlangen-Nürnberg, D-91058 Erlangen, Germany
| | - S Krief
- Bioprojet Biotech, 35762 Saint-Grégoire, France
| | - S Elz
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - K Friedland
- Department of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander Universität Erlangen-Nürnberg, D-91058 Erlangen, Germany
| | - G Bernhardt
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - J Wegener
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, D-93040 Regensburg, Germany
| | - T Ozawa
- Department of Chemistry, School of Science, University of Tokyo, Tokyo, Japan
| | - A Buschauer
- Institute of Pharmacy, University of Regensburg, D-93040 Regensburg, Germany.
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44
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Charpentier TH, Waldo GL, Lowery-Gionta EG, Krajewski K, Strahl BD, Kash TL, Harden TK, Sondek J. Potent and Selective Peptide-based Inhibition of the G Protein Gαq. J Biol Chem 2016; 291:25608-25616. [PMID: 27742837 DOI: 10.1074/jbc.m116.740407] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 10/13/2016] [Indexed: 11/06/2022] Open
Abstract
In contrast to G protein-coupled receptors, for which chemical and peptidic inhibitors have been extensively explored, few compounds are available that directly modulate heterotrimeric G proteins. Active Gαq binds its two major classes of effectors, the phospholipase C (PLC)-β isozymes and Rho guanine nucleotide exchange factors (RhoGEFs) related to Trio, in a strikingly similar fashion: a continuous helix-turn-helix of the effectors engages Gαq within its canonical binding site consisting of a groove formed between switch II and helix α3. This information was exploited to synthesize peptides that bound active Gαq in vitro with affinities similar to full-length effectors and directly competed with effectors for engagement of Gαq A representative peptide was specific for active Gαq because it did not bind inactive Gαq or other classes of active Gα subunits and did not inhibit the activation of PLC-β3 by Gβ1γ2 In contrast, the peptide robustly prevented activation of PLC-β3 or p63RhoGEF by Gαq; it also prevented G protein-coupled receptor-promoted neuronal depolarization downstream of Gαq in the mouse prefrontal cortex. Moreover, a genetically encoded form of this peptide flanked by fluorescent proteins inhibited Gαq-dependent activation of PLC-β3 at least as effectively as a dominant-negative form of full-length PLC-β3. These attributes suggest that related, cell-penetrating peptides should effectively inhibit active Gαq in cells and that these and genetically encoded sequences may find application as molecular probes, drug leads, and biosensors to monitor the spatiotemporal activation of Gαq in cells.
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Affiliation(s)
- Thomas H Charpentier
- From the Departments of Pharmacology and.,Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | | | | | - Krzysztof Krajewski
- Biochemistry and Biophysics.,High-Throughput Peptide Synthesis and Array Facility, and
| | - Brian D Strahl
- Biochemistry and Biophysics.,High-Throughput Peptide Synthesis and Array Facility, and
| | | | | | - John Sondek
- From the Departments of Pharmacology and .,Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599.,Biochemistry and Biophysics
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45
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van Unen J, Rashidfarrokhi A, Hoogendoorn E, Postma M, Gadella TWJ, Goedhart J. Quantitative Single-Cell Analysis of Signaling Pathways Activated Immediately Downstream of Histamine Receptor Subtypes. Mol Pharmacol 2016; 90:162-76. [PMID: 27358232 DOI: 10.1124/mol.116.104505] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/28/2016] [Indexed: 01/09/2023] Open
Abstract
Genetically encoded biosensors based on Förster resonance energy transfer (FRET) can visualize responses of individual cells in real time. Here, we evaluated whether FRET-based biosensors provide sufficient contrast and specificity to measure activity of G-protein-coupled receptors. The four histamine receptor subtypes (H1R, H2R, H3R, and H4R) respond to the ligand histamine by activating three canonical heterotrimeric G-protein-mediated signaling pathways with a reported high degree of specificity. Using FRET-based biosensors, we demonstrate that H1R activates Gαq. We also observed that H1R activates Gαi, albeit at a 10-fold lower potency. In addition to increasing cAMP levels, most likely via Gαs, we found that the H2R induces Gαq-mediated calcium release. The H3R and H4R activated Gαi with high specificity and a high potency. We demonstrate that a number of FRET sensors provide sufficient contrast to: 1) analyze the specificity of the histamine receptor subtypes for different heterotrimeric G-protein families with single-cell resolution, 2) probe for antagonist specificity, and 3) allow the measurement of single-cell concentration-response curves.
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Affiliation(s)
- Jakobus van Unen
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Ali Rashidfarrokhi
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Eelco Hoogendoorn
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Marten Postma
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Theodorus W J Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
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46
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Stanley RJ, Thomas GMH. Activation of G Proteins by Guanine Nucleotide Exchange Factors Relies on GTPase Activity. PLoS One 2016; 11:e0151861. [PMID: 26986850 PMCID: PMC4795700 DOI: 10.1371/journal.pone.0151861] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 03/04/2016] [Indexed: 11/18/2022] Open
Abstract
G proteins are an important family of signalling molecules controlled by guanine nucleotide exchange and GTPase activity in what is commonly called an 'activation/inactivation cycle'. The molecular mechanism by which guanine nucleotide exchange factors (GEFs) catalyse the activation of monomeric G proteins is well-established, however the complete reversibility of this mechanism is often overlooked. Here, we use a theoretical approach to prove that GEFs are unable to positively control G protein systems at steady-state in the absence of GTPase activity. Instead, positive regulation of G proteins must be seen as a product of the competition between guanine nucleotide exchange and GTPase activity--emphasising a central role for GTPase activity beyond merely signal termination. We conclude that a more accurate description of the regulation of G proteins via these processes is as a 'balance/imbalance' mechanism. This result has implications for the understanding of intracellular signalling processes, and for experimental strategies that rely on modulating G protein systems.
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Affiliation(s)
- Rob J. Stanley
- CoMPLEX, University College London, London, United Kingdom
- Department of Cell & Developmental Biology, University College London, London, United Kingdom
| | - Geraint M. H. Thomas
- CoMPLEX, University College London, London, United Kingdom
- Department of Cell & Developmental Biology, University College London, London, United Kingdom
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47
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Panula P, Chazot PL, Cowart M, Gutzmer R, Leurs R, Liu WLS, Stark H, Thurmond RL, Haas HL. International Union of Basic and Clinical Pharmacology. XCVIII. Histamine Receptors. Pharmacol Rev 2016; 67:601-55. [PMID: 26084539 DOI: 10.1124/pr.114.010249] [Citation(s) in RCA: 362] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Histamine is a developmentally highly conserved autacoid found in most vertebrate tissues. Its physiological functions are mediated by four 7-transmembrane G protein-coupled receptors (H1R, H2R, H3R, H4R) that are all targets of pharmacological intervention. The receptors display molecular heterogeneity and constitutive activity. H1R antagonists are long known antiallergic and sedating drugs, whereas the H2R was identified in the 1970s and led to the development of H2R-antagonists that revolutionized stomach ulcer treatment. The crystal structure of ligand-bound H1R has rendered it possible to design new ligands with novel properties. The H3R is an autoreceptor and heteroreceptor providing negative feedback on histaminergic and inhibition on other neurons. A block of these actions promotes waking. The H4R occurs on immuncompetent cells and the development of anti-inflammatory drugs is anticipated.
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Affiliation(s)
- Pertti Panula
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Paul L Chazot
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Marlon Cowart
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Ralf Gutzmer
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Rob Leurs
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Wai L S Liu
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Holger Stark
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Robin L Thurmond
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Helmut L Haas
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
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48
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van Unen J, Stumpf AD, Schmid B, Reinhard NR, Hordijk PL, Hoffmann C, Gadella TWJ, Goedhart J. A New Generation of FRET Sensors for Robust Measurement of Gαi1, Gαi2 and Gαi3 Activation Kinetics in Single Cells. PLoS One 2016; 11:e0146789. [PMID: 26799488 PMCID: PMC4723041 DOI: 10.1371/journal.pone.0146789] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 12/22/2015] [Indexed: 01/14/2023] Open
Abstract
G-protein coupled receptors (GPCRs) can activate a heterotrimeric G-protein complex with subsecond kinetics. Genetically encoded biosensors based on Förster resonance energy transfer (FRET) are ideally suited for the study of such fast signaling events in single living cells. Here we report on the construction and characterization of three FRET biosensors for the measurement of Gαi1, Gαi2 and Gαi3 activation. To enable quantitative long-term imaging of FRET biosensors with high dynamic range, fluorescent proteins with enhanced photophysical properties are required. Therefore, we use the currently brightest and most photostable CFP variant, mTurquoise2, as donor fused to Gαi subunit, and cp173Venus fused to the Gγ2 subunit as acceptor. The Gαi FRET biosensors constructs are expressed together with Gβ1 from a single plasmid, providing preferred relative expression levels with reduced variation in mammalian cells. The Gαi FRET sensors showed a robust response to activation of endogenous or over-expressed alpha-2A-adrenergic receptors, which was inhibited by pertussis toxin. Moreover, we observed activation of the Gαi FRET sensor in single cells upon stimulation of several GPCRs, including the LPA2, M3 and BK2 receptor. Furthermore, we show that the sensors are well suited to extract kinetic parameters from fast measurements in the millisecond time range. This new generation of FRET biosensors for Gαi1, Gαi2 and Gαi3 activation will be valuable for live-cell measurements that probe Gαi activation.
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Affiliation(s)
- Jakobus van Unen
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Anette D Stumpf
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Benedikt Schmid
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Nathalie R Reinhard
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands.,Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, NL-1066 CX, Amsterdam, the Netherlands
| | - Peter L Hordijk
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands.,Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, NL-1066 CX, Amsterdam, the Netherlands
| | - Carsten Hoffmann
- Bio-Imaging-Center/Rudolf-Virchow-Zentrum and Department of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, 97078, Wuerzburg, Germany
| | - Theodorus W J Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, P.O. Box 94215, NL-1090 GE, Amsterdam, The Netherlands
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49
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Abstract
Fluorescence fluctuation spectroscopy techniques allow the quantification of fluorescent molecules present at the nanomolar concentration level. After a brief introduction to the technique, this chapter presents a protocol including background information in order to measure and quantify the molecular interaction of two signaling proteins inside the living cell using fluorescence cross-correlation spectroscopy.
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Affiliation(s)
- Mark A Hink
- Department Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy (LCAM), University of Amsterdam, Sciencepark 904, 1098 XH, Amsterdam, The Netherlands,
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50
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Bojjireddy N, Guzman-Hernandez ML, Reinhard NR, Jovic M, Balla T. EFR3s are palmitoylated plasma membrane proteins that control responsiveness to G-protein-coupled receptors. J Cell Sci 2014; 128:118-28. [PMID: 25380825 DOI: 10.1242/jcs.157495] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The yeast Efr3p protein is a main regulator of the Stt4p phosphatidylinositol 4-kinase at contact sites between the endoplasmic reticulum and the plasma membrane. A mutation in its fly homologue Rbo, leads to diminished light responses in the eye attributed to progressively impaired PLC signaling. Here, we find that Efr3s plays a role in maintaining responsiveness to the type-I angiotensin II (AngII) receptors. siRNA-mediated depletion of EFR3A and EFR3B impaired the sustained phase of cytosolic Ca(2+) response to high concentration of AngII in HEK293 cells that express wild type but not truncated AGTR1 (AT1a receptor), missing the phosphorylation sites. Efr3 depletion had minimal effect on the recovery of plasma membrane phosphoinositides during stimulation, and AT1 receptors still underwent ligand-induced internalization. A higher level of basal receptor phosphorylation and a larger response was observed after stimulation. Moreover, Gq activation more rapidly desensitized after AngII stimulation in Efr3 downregulated cells. A similar but less pronounced effect of EFR3 depletion was observed on the desensitization of the cAMP response after stimulation with isoproterenol. These data suggest that mammalian Efr3s contribute to the control of the phosphorylation state and, hence, desensitization of AT1a receptors, and could affect responsiveness of G-protein-coupled receptors in higher eukaryotes.
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Affiliation(s)
- Naveen Bojjireddy
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maria Luisa Guzman-Hernandez
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nathalie Renée Reinhard
- Swammerdam Institute for Life Sciences, University of Amsterdam, 1012 WX Amsterdam, The Netherlands
| | - Marko Jovic
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tamas Balla
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD 20892, USA
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