1
|
Matthees ESF, Filor JC, Jaiswal N, Reichel M, Youssef N, D'Uonnolo G, Szpakowska M, Drube J, König GM, Kostenis E, Chevigné A, Godbole A, Hoffmann C. GRK specificity and Gβγ dependency determines the potential of a GPCR for arrestin-biased agonism. Commun Biol 2024; 7:802. [PMID: 38956302 PMCID: PMC11220067 DOI: 10.1038/s42003-024-06490-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 06/21/2024] [Indexed: 07/04/2024] Open
Abstract
G protein-coupled receptors (GPCRs) are mainly regulated by GPCR kinase (GRK) phosphorylation and subsequent β-arrestin recruitment. The ubiquitously expressed GRKs are classified into cytosolic GRK2/3 and membrane-tethered GRK5/6 subfamilies. GRK2/3 interact with activated G protein βγ-subunits to translocate to the membrane. Yet, this need was not linked as a factor for bias, influencing the effectiveness of β-arrestin-biased agonist creation. Using multiple approaches such as GRK2/3 mutants unable to interact with Gβγ, membrane-tethered GRKs and G protein inhibitors in GRK2/3/5/6 knockout cells, we show that G protein activation will precede GRK2/3-mediated β-arrestin2 recruitment to activated receptors. This was independent of the source of free Gβγ and observable for Gs-, Gi- and Gq-coupled GPCRs. Thus, β-arrestin interaction for GRK2/3-regulated receptors is inseparably connected with G protein activation. We outline a theoretical framework of how GRK dependence on free Gβγ can determine a GPCR's potential for biased agonism. Due to this inherent cellular mechanism for GRK2/3 recruitment and receptor phosphorylation, we anticipate generation of β-arrestin-biased ligands to be mechanistically challenging for the subgroup of GPCRs exclusively regulated by GRK2/3, but achievable for GRK5/6-regulated receptors, that do not demand liberated Gβγ. Accordingly, GRK specificity of any GPCR is foundational for developing arrestin-biased ligands.
Collapse
Affiliation(s)
- Edda S F Matthees
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Jenny C Filor
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Natasha Jaiswal
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
- Department of Internal Medicine, Section of Gerontology and Geriatric Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Mona Reichel
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Noureldine Youssef
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Giulia D'Uonnolo
- Immuno-Pharmacology and Interactomics, Department of Infection and Immunity, Luxembourg Institute of Health (LIH), 29 rue Henri Koch, L-4354, Esch-sur-Alzette, Luxembourg
- Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Martyna Szpakowska
- Immuno-Pharmacology and Interactomics, Department of Infection and Immunity, Luxembourg Institute of Health (LIH), 29 rue Henri Koch, L-4354, Esch-sur-Alzette, Luxembourg
| | - Julia Drube
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Gabriele M König
- Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, D-53115, Bonn, Germany
| | - Evi Kostenis
- Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, D-53115, Bonn, Germany
| | - Andy Chevigné
- Immuno-Pharmacology and Interactomics, Department of Infection and Immunity, Luxembourg Institute of Health (LIH), 29 rue Henri Koch, L-4354, Esch-sur-Alzette, Luxembourg
| | - Amod Godbole
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany
| | - Carsten Hoffmann
- Institut für Molekulare Zellbiologie, CMB - Center for Molecular Biomedicine; Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Hans-Knöll-Straße 2, D-07745, Jena, Germany.
| |
Collapse
|
2
|
Gardner J, Eiger DS, Hicks C, Choi I, Pham U, Chundi A, Namjoshi O, Rajagopal S. GPCR kinases differentially modulate biased signaling downstream of CXCR3 depending on their subcellular localization. Sci Signal 2024; 17:eadd9139. [PMID: 38349966 PMCID: PMC10927030 DOI: 10.1126/scisignal.add9139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 01/22/2024] [Indexed: 02/15/2024]
Abstract
Some G protein-coupled receptors (GPCRs) demonstrate biased signaling such that ligands of the same receptor exclusively or preferentially activate certain downstream signaling pathways over others. This phenomenon may result from ligand-specific receptor phosphorylation by GPCR kinases (GRKs). GPCR signaling can also exhibit location bias because GPCRs traffic to and signal from subcellular compartments in addition to the plasma membrane. Here, we investigated whether GRKs contributed to location bias in GPCR signaling. GRKs translocated to endosomes after stimulation of the chemokine receptor CXCR3 or other GPCRs in cultured cells. GRK2, GRK3, GRK5, and GRK6 showed distinct patterns of recruitment to the plasma membrane and to endosomes depending on the identity of the biased ligand used to activate CXCR3. Analysis of engineered forms of GRKs that localized to either the plasma membrane or endosomes demonstrated that biased CXCR3 ligands elicited different signaling profiles that depended on the subcellular location of the GRK. Each GRK exerted a distinct effect on the regulation of CXCR3 engagement of β-arrestin, internalization, and activation of the downstream effector kinase ERK. Our work highlights a role for GRKs in location-biased GPCR signaling and demonstrates the complex interactions between ligands, GRKs, and cellular location that contribute to biased signaling.
Collapse
Affiliation(s)
- Julia Gardner
- Trinity College, Duke University, Durham, NC, 27710, USA
| | | | - Chloe Hicks
- Trinity College, Duke University, Durham, NC, 27710, USA
| | - Issac Choi
- Department of Medicine, Duke University, Durham, NC, 27710, USA
| | - Uyen Pham
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
| | - Anand Chundi
- Pratt School of Engineering, Duke University, Durham, NC, 27710, USA
| | - Ojas Namjoshi
- Center for Drug Discovery RTI International, Research Triangle Park, NC, 27709, USA
- Present address: Engine Biosciences, 733 Industrial Rd., San Carlos, CA, 94070, USA
| | - Sudarshan Rajagopal
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
- Department of Medicine, Duke University, Durham, NC, 27710, USA
| |
Collapse
|
3
|
Ham S, Mukaida S, Sato M, Keov P, Bengtsson T, Furness S, Holliday ND, Evans BA, Summers RJ, Hutchinson DS. Role of G protein-coupled receptor kinases (GRKs) in β 2 -adrenoceptor-mediated glucose uptake. Pharmacol Res Perspect 2024; 12:e1176. [PMID: 38332691 PMCID: PMC10853676 DOI: 10.1002/prp2.1176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 12/17/2023] [Accepted: 01/22/2024] [Indexed: 02/10/2024] Open
Abstract
Truncation of the C-terminal tail of the β2 -AR, transfection of βARKct or over-expression of a kinase-dead GRK mutant reduces isoprenaline-stimulated glucose uptake, indicating that GRK is important for this response. We explored whether phosphorylation of the β2 -AR by GRK2 has a role in glucose uptake or if this response is related to the role of GRK2 as a scaffolding protein. CHO-GLUT4myc cells expressing wild-type and mutant β2 -ARs were generated and receptor affinity for [3 H]-CGP12177A and density of binding sites determined together with the affinity of isoprenaline and BRL37344. Following receptor activation by β2 -AR agonists, cAMP accumulation, GLUT4 translocation, [3 H]-2-deoxyglucose uptake, and β2 -AR internalization were measured. Bioluminescence resonance energy transfer was used to investigate interactions between β2 -AR and β-arrestin2 or between β2 -AR and GRK2. Glucose uptake after siRNA knockdown or GRK inhibitors was measured in response to β2 -AR agonists. BRL37344 was a poor partial agonist for cAMP generation but displayed similar potency and efficacy to isoprenaline for glucose uptake and GLUT4 translocation. These responses to β2 -AR agonists occurred in CHO-GLUT4myc cells expressing β2 -ARs lacking GRK or GRK/PKA phosphorylation sites as well as in cells expressing the wild-type β2 -AR. However, β2 -ARs lacking phosphorylation sites failed to recruit β-arrestin2 and did not internalize. GRK2 knock-down or GRK2 inhibitors decreased isoprenaline-stimulated glucose uptake in rat L6 skeletal muscle cells. Thus, GRK phosphorylation of the β2 -AR is not associated with isoprenaline- or BRL37344-stimulated glucose uptake. However, GRKs acting as scaffold proteins are important for glucose uptake as GRK2 knock-down or GRK2 inhibition reduces isoprenaline-stimulated glucose uptake.
Collapse
Affiliation(s)
- Seungmin Ham
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Saori Mukaida
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Masaaki Sato
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Peter Keov
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Tore Bengtsson
- Atrogi ABStockholmSweden
- Department of Molecular BiosciencesThe Wenner‐Gren Institute, Stockholm UniversityStockholmSweden
| | - Sebastian Furness
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Nicholas D. Holliday
- School of Life Sciences, The Medical School, Queen's Medical CentreUniversity of NottinghamNottinghamUK
- Excellerate Bioscience, BiocityNottinghamUK
| | - Bronwyn A. Evans
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Roger J. Summers
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| | - Dana S. Hutchinson
- Drug Discovery BiologyMonash Institute of Pharmaceutical Sciences, Monash UniversityParkvilleVictoriaAustralia
| |
Collapse
|
4
|
Schafer CT, Chen Q, Tesmer JJG, Handel TM. Atypical Chemokine Receptor 3 "Senses" CXC Chemokine Receptor 4 Activation Through GPCR Kinase Phosphorylation. Mol Pharmacol 2023; 104:174-186. [PMID: 37474305 PMCID: PMC11033958 DOI: 10.1124/molpharm.123.000710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/22/2023] [Accepted: 06/30/2023] [Indexed: 07/22/2023] Open
Abstract
Atypical chemokine receptor 3 (ACKR3) is an arrestin-biased receptor that regulates extracellular chemokine levels through scavenging. The scavenging process restricts the availability of the chemokine agonist CXCL12 for the G protein-coupled receptor (GPCR) CXCR4 and requires phosphorylation of the ACKR3 C-terminus by GPCR kinases (GRKs). ACKR3 is phosphorylated by GRK2 and GRK5, but the mechanisms by which these kinases regulate the receptor are unresolved. Here we determined that GRK5 phosphorylation of ACKR3 results in more efficient chemokine scavenging and β-arrestin recruitment than phosphorylation by GRK2 in HEK293 cells. However, co-activation of CXCR4-enhanced ACKR3 phosphorylation by GRK2 through the liberation of Gβγ, an accessory protein required for efficient GRK2 activity. The results suggest that ACKR3 "senses" CXCR4 activation through a GRK2-dependent crosstalk mechanism, which enables CXCR4 to influence the efficiency of CXCL12 scavenging and β-arrestin recruitment to ACKR3. Surprisingly, we also found that despite the requirement for phosphorylation and the fact that most ligands promote β-arrestin recruitment, β-arrestins are dispensable for ACKR3 internalization and scavenging, suggesting a yet-to-be-determined function for these adapter proteins. Since ACKR3 is also a receptor for CXCL11 and opioid peptides, these data suggest that such crosstalk may also be operative in cells with CXCR3 and opioid receptor co-expression. Additionally, kinase-mediated receptor cross-regulation may be relevant to other atypical and G protein-coupled receptors that share common ligands. SIGNIFICANCE STATEMENT: The atypical receptor ACKR3 indirectly regulates CXCR4-mediated cell migration by scavenging their shared agonist CXCL12. Here, we show that scavenging and β-arrestin recruitment by ACKR3 are primarily dependent on phosphorylation by GRK5. However, we also show that CXCR4 co-activation enhances the contribution of GRK2 by liberating Gβγ. This phosphorylation crosstalk may represent a common feedback mechanism between atypical and G protein-coupled receptors with shared ligands for regulating the efficiency of scavenging or other atypical receptor functions.
Collapse
Affiliation(s)
- Christopher T Schafer
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California (C.T.S., T.M.H.) and Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (Q.C., J.J.G.T.)
| | - Qiuyan Chen
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California (C.T.S., T.M.H.) and Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (Q.C., J.J.G.T.)
| | - John J G Tesmer
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California (C.T.S., T.M.H.) and Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (Q.C., J.J.G.T.)
| | - Tracy M Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California (C.T.S., T.M.H.) and Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (Q.C., J.J.G.T.)
| |
Collapse
|
5
|
Schafer CT, Chen Q, Tesmer JJG, Handel TM. Atypical Chemokine Receptor 3 'Senses' CXC Chemokine Receptor 4 Activation Through GPCR Kinase Phosphorylation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.25.530029. [PMID: 36865154 PMCID: PMC9980177 DOI: 10.1101/2023.02.25.530029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Atypical chemokine receptor 3 (ACKR3) is an arrestin-biased receptor that regulates extracellular chemokine levels through scavenging. The scavenging action mediates the availability of the chemokine CXCL12 for the G protein-coupled receptor (GPCR) CXCR4 and requires phosphorylation of the ACKR3 C-terminus by GPCR kinases (GRKs). ACKR3 is phosphorylated by GRK2 and GRK5, but the mechanisms by which these kinases regulate the receptor are unresolved. Here we mapped the phosphorylation patterns and determined that GRK5 phosphorylation of ACKR3 dominates β-arrestin recruitment and chemokine scavenging over GRK2. Co-activation of CXCR4 significantly enhanced phosphorylation by GRK2 through the liberation of Gβγ. These results suggest that ACKR3 'senses' CXCR4 activation through a GRK2-dependent crosstalk mechanism. Surprisingly, we also found that despite the requirement for phosphorylation, and the fact that most ligands promote β-arrestin recruitment, β-arrestins are dispensable for ACKR3 internalization and scavenging, suggesting a yet to be determined function for these adapter proteins.
Collapse
Affiliation(s)
- Christopher T. Schafer
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, USA
| | - Qiuyan Chen
- Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
- Present address: Dept. of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - John J. G. Tesmer
- Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
| | - Tracy M. Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, USA
| |
Collapse
|
6
|
Shroka TM, Kufareva I, Salanga CL, Handel TM. The dual-function chemokine receptor CCR2 drives migration and chemokine scavenging through distinct mechanisms. Sci Signal 2023; 16:eabo4314. [PMID: 36719944 PMCID: PMC10091583 DOI: 10.1126/scisignal.abo4314] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
C-C chemokine receptor 2 (CCR2) is a dual-function receptor. Similar to other G protein-coupled chemokine receptors, it promotes monocyte infiltration into tissues in response to the chemokine CCL2, and, like atypical chemokine receptors (ACKRs), it scavenges chemokine from the extracellular environment. CCR2 therefore mediates CCL2-dependent signaling as a G protein-coupled receptor (GPCR) and also limits CCL2 signaling as a scavenger receptor. We investigated the mechanisms underlying CCR2 scavenging, including the involvement of intracellular proteins typically associated with GPCR signaling and internalization. Using CRISPR knockout cell lines, we showed that CCR2 scavenged by constitutively internalizing to remove CCL2 from the extracellular space and recycling back to the cell surface for further rounds of ligand sequestration. This process occurred independently of G proteins, GPCR kinases (GRKs), β-arrestins, and clathrin, which is distinct from other "professional" chemokine scavenger receptors that couple to GRKs, β-arrestins, or both. These findings set the stage for understanding the molecular regulators that determine CCR2 scavenging and may have implications for drug development targeting this therapeutically important receptor.
Collapse
Affiliation(s)
- Thomas M Shroka
- Biomedical Sciences Program, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Catherina L Salanga
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Tracy M Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| |
Collapse
|
7
|
Ferrero KM, Koch WJ. GRK2 in cardiovascular disease and its potential as a therapeutic target. J Mol Cell Cardiol 2022; 172:14-23. [PMID: 35878706 DOI: 10.1016/j.yjmcc.2022.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/29/2022] [Accepted: 07/19/2022] [Indexed: 01/25/2023]
Abstract
Cardiovascular diseases (CVDs) represent the leading cause of death globally. Despite major advances in the field of pharmacological CVD treatments, particularly in the field of heart failure (HF) research, case numbers and overall mortality remain high and have trended upwards over the last few years. Thus, identifying novel molecular targets for developing HF therapeutics remains a key research focus. G protein-coupled receptors (GPCRs) are critical myocardial signal transducers which regulate cardiac contractility, growth, adaptation and metabolism. Additionally, GPCR dysregulation underlies multiple models of cardiac pathology, and most pharmacological therapeutics currently used in HF target these receptors. Currently-approved treatments have improved patient outcomes, but therapies to stop or reverse HF are lacking. A recent focus on GPCR intracellular-regulating proteins such as GPCR kinases (GRKs) has uncovered GRK2 as a promising target for combating HF. Current literature strongly establishes increased levels and activity of GRK2 in multiple models of CVD. Additionally, the GRK2 interactome includes numerous proteins which interact with differential domains of GRK2 to modulate both beneficial and deleterious signaling pathways in the heart, indicating that these domains can be targeted with a high level of specificity unique to various cardiac pathologies. These data support the premise that GRK2 should be at the forefront of a novel investigative drug search. This perspective reviews cardiac GPCRs, describes the structure and functions of GRK2 in cardiac function and maladaptive pathology, and summarizes the ongoing and future research for targeting this critical kinase across cellular, animal and human models of cardiac dysfunction and HF.
Collapse
Affiliation(s)
- Kimberly M Ferrero
- Lewis Katz School of Medicine at Temple University, Department of Cardiovascular Sciences, Philadelphia, PA, USA; Lewis Katz School of Medicine at Temple University, Center for Translational Medicine, Philadelphia, PA, USA
| | - Walter J Koch
- Lewis Katz School of Medicine at Temple University, Department of Cardiovascular Sciences, Philadelphia, PA, USA; Lewis Katz School of Medicine at Temple University, Center for Translational Medicine, Philadelphia, PA, USA.
| |
Collapse
|
8
|
Jiang H, Galtes D, Wang J, Rockman HA. G protein-coupled receptor signaling: transducers and effectors. Am J Physiol Cell Physiol 2022; 323:C731-C748. [PMID: 35816644 PMCID: PMC9448338 DOI: 10.1152/ajpcell.00210.2022] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/27/2022] [Accepted: 07/10/2022] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCRs) are of considerable interest due to their importance in a wide range of physiological functions and in a large number of Food and Drug Administration (FDA)-approved drugs as therapeutic entities. With continued study of their function and mechanism of action, there is a greater understanding of how effector molecules interact with a receptor to initiate downstream effector signaling. This review aims to explore the signaling pathways, dynamic structures, and physiological relevance in the cardiovascular system of the three most important GPCR signaling effectors: heterotrimeric G proteins, GPCR kinases (GRKs), and β-arrestins. We will first summarize their prominent roles in GPCR pharmacology before transitioning into less well-explored areas. As new technologies are developed and applied to studying GPCR structure and their downstream effectors, there is increasing appreciation for the elegance of the regulatory mechanisms that mediate intracellular signaling and function.
Collapse
Affiliation(s)
- Haoran Jiang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Daniella Galtes
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Jialu Wang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina
| |
Collapse
|
9
|
Sex/Gender- and Age-Related Differences in β-Adrenergic Receptor Signaling in Cardiovascular Diseases. J Clin Med 2022; 11:jcm11154280. [PMID: 35893368 PMCID: PMC9330499 DOI: 10.3390/jcm11154280] [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: 06/10/2022] [Revised: 07/15/2022] [Accepted: 07/22/2022] [Indexed: 11/17/2022] Open
Abstract
Sex differences in cardiovascular disease (CVD) are often recognized from experimental and clinical studies examining the prevalence, manifestations, and response to therapies. Compared to age-matched men, women tend to have reduced CV risk and a better prognosis in the premenopausal period. However, with menopause, this risk increases exponentially, surpassing that of men. Although several mechanisms have been provided, including sex hormones, an emerging role in these sex differences has been suggested for β-adrenergic receptor (β-AR) signaling. Importantly, β-ARs are the most important G protein-coupled receptors (GPCRs), expressed in almost all the cell types of the CV system, and involved in physiological and pathophysiological processes. Consistent with their role, for decades, βARs have been considered the first targets for rational drug design to fight CVDs. Of note, β-ARs are seemingly associated with different CV outcomes in females compared with males. In addition, even if there is a critical inverse correlation between β-AR responsiveness and aging, it has been reported that gender is crucially involved in this age-related effect. This review will discuss how β-ARs impact the CV risk and response to anti-CVD therapies, also concerning sex and age. Further, we will explore how estrogens impact β-AR signaling in women.
Collapse
|
10
|
GRK2 regulates ADP signaling in platelets via P2Y1 and P2Y12. Blood Adv 2022; 6:4524-4536. [PMID: 35793439 DOI: 10.1182/bloodadvances.2022007007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 06/10/2022] [Indexed: 11/20/2022] Open
Abstract
The critical role of GRK2 in regulating cardiac function has been well documented for over three decades. Therefore, targeting GRK2 has been extensively studied as a novel approach to treat cardiovascular disease. However, little is known about its role in hemostasis and thrombosis. Here we provide the first evidence that GRK2 limits platelet activation and regulates the hemostatic response to injury. Deletion of GRK2 in mouse platelets causes increased platelet accumulation following laser-induced injury in cremaster muscle arterioles, shortens tail bleeding time, and enhances thrombosis in ADP-induced pulmonary thromboembolism and in FeCl3-induced carotid injury. GRK2-/- platelets have increased integrin activation, P-selectin exposure, and platelet aggregation in response to ADP stimulation. Furthermore, GRK2-/- platelets retain the ability to aggregate in response to ADP re-stimulation, indicating that GRK2 contributes to ADP receptor desensitization. Underlying these changes in GRK2-/- platelets is an increase in Ca2+ mobilization, RAP1 activation, and Akt phosphorylation stimulated by ADP, and an attenuated rise of cAMP levels in response to ADP in the presence of prostaglandin I2. P2Y12 antagonist treatment eliminates the phenotypic difference in platelet accumulation between WT and GRK2-/- mice at the site of injury. Pharmacologic inhibition of GRK2 activity in human platelets increases platelet activation in response to ADP. Finally, we show that GRK2 binds to endogenous Gβγ subunits during platelet activation. Collectively, these results show that GRK2 regulates ADP signaling via P2Y1 and P2Y12, interacts with Gβγ, and functions as a signaling hub in platelets for modulating the hemostatic response to injury.
Collapse
|
11
|
Pearce A, Redfern-Nichols T, Harris M, Poyner DR, Wigglesworth M, Ladds G. Determining the Effects of Differential Expression of GRKs and β-arrestins on CLR-RAMP Agonist Bias. Front Physiol 2022; 13:840763. [PMID: 35422711 PMCID: PMC9001978 DOI: 10.3389/fphys.2022.840763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/08/2022] [Indexed: 11/17/2022] Open
Abstract
Signalling of the calcitonin-like receptor (CLR) is multifaceted, due to its interaction with receptor activity modifying proteins (RAMPs), and three endogenous peptide agonists. Previous studies have focused on the bias of G protein signalling mediated by the receptor and receptor internalisation of the CLR-RAMP complex has been assumed to follow the same pattern as other Class B1 G Protein-Coupled Receptors (GPCRs). Here we sought to measure desensitisation of the three CLR-RAMP complexes in response to the three peptide agonists, through the measurement of β-arrestin recruitment and internalisation. We then delved further into the mechanism of desensitisation through modulation of β-arrestin activity and the expression of GPCR kinases (GRKs), a key component of homologous GPCR desensitisation. First, we have shown that CLR-RAMP1 is capable of potently recruiting β-arrestin1 and 2, subsequently undergoing rapid endocytosis, and that CLR-RAMP2 and -RAMP3 also utilise these pathways, although to a lesser extent. Following this we have shown that agonist-dependent internalisation of CLR is β-arrestin dependent, but not required for full agonism. Overexpression of GRK2-6 was then found to decrease receptor signalling, due to an agonist-independent reduction in surface expression of the CLR-RAMP complex. These results represent the first systematic analysis of the importance of β-arrestins and GRKs in CLR-RAMP signal transduction and pave the way for further investigation regarding other Class B1 GPCRs.
Collapse
Affiliation(s)
- Abigail Pearce
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | | | - Matthew Harris
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - David R. Poyner
- School of Life and Health Sciences, Aston University, Birmingham, United Kingdom
| | - Mark Wigglesworth
- Hit Discovery, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, London, United Kingdom
| | - Graham Ladds
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: Graham Ladds,
| |
Collapse
|
12
|
Gazdarica M, Noda J, Durydivka O, Novosadova V, Mackie K, Pin JP, Prezeau L, Blahos J. SGIP1 modulates kinetics and interactions of the cannabinoid receptor 1 and G protein-coupled receptor kinase 3 signalosome. J Neurochem 2021; 160:625-642. [PMID: 34970999 PMCID: PMC9306533 DOI: 10.1111/jnc.15569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 12/23/2021] [Accepted: 12/23/2021] [Indexed: 12/05/2022]
Abstract
Cannabinoid receptor 1 (CB1R), a G protein‐coupled receptor, plays a fundamental role in synaptic plasticity. Abnormal activity and deregulation of CB1R signaling result in a broad spectrum of pathological conditions. CB1R signaling is regulated by receptor desensitization including phosphorylation of residues within the intracellular C terminus by G protein‐coupled receptor kinases (GRKs) that may lead to endocytosis. Furthermore, CB1R signaling is regulated by the protein Src homology 3‐domain growth factor receptor‐bound 2‐like (SGIP1) that hinders receptor internalization, while enhancing CB1R association with β‐arrestin. It has been postulated that phosphorylation of two clusters of serine/threonine residues, 425SMGDS429 and 460TMSVSTDTS468, within the CB1R C‐tail controls dynamics of the association between receptor and its interaction partners involved in desensitization. Several molecular determinants of these events are still not well understood. We hypothesized that the dynamics of these interactions are modulated by SGIP1. Using a panel of CB1Rs mutated in the aforementioned serine and threonine residues, together with an array of Bioluminescence energy transfer‐based (BRET) sensors, we discovered that GRK3 forms complexes with Gβγ subunits of G proteins that largely independent of GRK3’s interaction with CB1R. Furthermore, CB1R interacts only with activated GRK3. Interestingly, phosphorylation of two specific residues on CB1R triggers GRK3 dissociation from the desensitized receptor. SGIP1 increases the association of GRK3 with Gβγ subunits of G proteins, and with CB1R. Altogether, our data suggest that the CB1R signalosome complex is dynamically controlled by sequential phosphorylation of the receptor C‐tail and is also modified by SGIP1.
Collapse
Affiliation(s)
- Matej Gazdarica
- Institute of Molecular Genetics, Czech Academy of Science, Videnska 1083, 14220, Prague 4, Czech Republic.,Institut de Génomique Fonctionnelle, Université Montpellier 1 and 2, Montpellier, France
| | - Judith Noda
- Institute of Molecular Genetics, Czech Academy of Science, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Oleh Durydivka
- Institute of Molecular Genetics, Czech Academy of Science, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Vendula Novosadova
- The Czech Center for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prumyslova 595, 252 50, Vestec, Czech Republic
| | - Ken Mackie
- Department of Psychological and Brain Sciences, Gill Center for Molecular Bioscience, Indiana University, 1101 E. 10th St, Bloomington, IN, USA, 47405
| | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle, Université Montpellier 1 and 2, Montpellier, France
| | - Laurent Prezeau
- Institut de Génomique Fonctionnelle, Université Montpellier 1 and 2, Montpellier, France
| | - Jaroslav Blahos
- Institute of Molecular Genetics, Czech Academy of Science, Videnska 1083, 14220, Prague 4, Czech Republic
| |
Collapse
|
13
|
Resolvin D2 and Resolvin D1 Differentially Activate Protein Kinases to Counter-Regulate Histamine-Induced [Ca2+]i Increase and Mucin Secretion in Conjunctival Goblet Cells. Int J Mol Sci 2021; 23:ijms23010141. [PMID: 35008563 PMCID: PMC8745650 DOI: 10.3390/ijms23010141] [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: 10/19/2021] [Revised: 12/02/2021] [Accepted: 12/17/2021] [Indexed: 11/20/2022] Open
Abstract
Resolvin (Rv) D2 and RvD1 are biosynthesized from docosahexaenoic acid (DHA) and promote resolution of inflammation in multiple organs and tissues, including the conjunctiva. Histamine is a mediator produced by mast cells in the conjunctiva during the allergic response. We determined the interaction of RvD2 with histamine and its receptor subtypes in cultured conjunctival goblet cells and compared them with RvD1 by measuring intracellular [Ca2+] and mucous secretion. Treatment with RvD2 significantly blocked the histamine-induced [Ca2+]i increase as well as secretion. RvD2 and RvD1 counter-regulate different histamine receptor subtypes. RvD2 inhibited the increase in [Ca2+]i induced by the activation of H1, H3, or H4 receptors, whereas RvD1 inhibited H1 and H3 receptors. RvD2 and RvD1 also activate distinct receptor-specific protein kinases to counter-regulate the histamine receptors, probably by phosphorylation. Thus, our data suggest that the counter-regulation of H receptor subtypes by RvD2 and RvD1 to inhibit mucin secretion are separately regulated.
Collapse
|
14
|
GPR3 accelerates neurite outgrowth and neuronal polarity formation via PI3 kinase-mediating signaling pathway in cultured primary neurons. Mol Cell Neurosci 2021; 118:103691. [PMID: 34871769 DOI: 10.1016/j.mcn.2021.103691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 11/23/2022] Open
Abstract
During neuronal development, immature neurons extend neurites and subsequently polarize to form an axon and dendrites. We have previously reported that G protein-coupled receptor 3 (GPR3) levels increase during neuronal development, and that GPR3 has functions in neurite outgrowth and neuronal differentiation in cerebellar granular neurons. Moreover, GPR3 is transported and concentrated at the tips of neurite, thereby contributing to the local activation of protein kinase A (PKA). However, the signaling pathways for GPR3-mediated neurite outgrowth and its subsequent effects on neuronal polarization have not yet been elucidated. We therefore analyzed the signaling pathways related to GPR3-mediated neurite outgrowth, and also focused on the possible roles of GPR3 in axon polarization. We demonstrated that, in cerebellar granular neurons, GPR3-mediated neurite outgrowth was mediated by multiple signaling pathways, including those of PKA, extracellular signal-regulated kinases (ERKs), and most strongly phosphatidylinositol 3-kinase (PI3K). In addition, the GPR3-mediated activation of neurite outgrowth was associated with G protein-coupled receptor kinase 2 (GRK2)-mediated signaling and phosphorylation of the C-terminus serine/threonine residues of GPR3, which affected downstream protein kinase B (Akt) signaling. We further demonstrated that GPR3 was transiently increased early in the development of rodent hippocampal neurons. It was subsequently concentrated at the tip of the longest neurite, and was thus associated with accelerated polarity formation in a PI3K-dependent manner in rat hippocampal neurons. In addition, GPR3 knockout in mouse hippocampal neurons led to delayed neuronal polarity formation, thereby affecting the dephosphorylation of collapsing response mediator protein 2 (CRMP2), which is downstream of the PI3K signaling pathway. Taken together, these findings suggest that the intrinsic expression of GPR3 in differentiated neurons constitutively activates PI3K-mediated signaling pathway predominantly, thus accelerating neurite outgrowth and further augmenting polarity formation in primary cultured neurons.
Collapse
|
15
|
Mechanistic diversity involved in the desensitization of G protein-coupled receptors. Arch Pharm Res 2021; 44:342-353. [PMID: 33761113 DOI: 10.1007/s12272-021-01320-y] [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: 12/10/2020] [Accepted: 03/14/2021] [Indexed: 01/14/2023]
Abstract
The desensitization of G protein-coupled receptors (GPCRs), which involves rapid loss of responsiveness due to repeated or chronic exposure to agonists, can occur through various mechanisms at different levels of signaling pathways. In this review, the mechanisms of GPCR desensitization are classified according to their occurrence at the receptor level and downstream to the receptor. The desensitization at the receptor level occurs in a phosphorylation-dependent manner, wherein the activated receptors are phosphorylated by GPCR kinases (GRKs), thereby increasing their affinities for arrestins. Arrestins bind to receptors through the cavity on the cytoplasmic region of heptahelical domains and interfere with the binding and activation of G-protein. Diverse mechanisms are involved in the desensitization that occurs downstream of the receptor. Some of these include the sequestration of G proteins, such as Gq and Gi/o by GRK2/3 and deubiquitinated arrestins, respectively. Mechanistically, GRK2/3 attenuates GPCR signaling by sequestering the Gα subunits of the Gq family and Gβγ via regulators of G protein signaling and pleckstrin homology domains, respectively. Moreover, studies on Gi/o-coupled D2-like receptors have reported that arrestins are deubiquitinated under desensitization condition and form a stable complex with Gβγ, thereby preventing them from coupling with Gα and the receptor, eventually leading to receptor signaling inhibition. Notably, the desensitization mechanism that involves arrestin deubiquitination is interesting; however, this is a new mechanism and needs to be explored further.
Collapse
|
16
|
The Open Question of How GPCRs Interact with GPCR Kinases (GRKs). Biomolecules 2021; 11:biom11030447. [PMID: 33802765 PMCID: PMC8002388 DOI: 10.3390/biom11030447] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 01/14/2023] Open
Abstract
G protein-coupled receptors (GPCRs), which regulate a vast number of eukaryotic processes, are desensitized by various mechanisms but, most importantly, by the GPCR kinases (GRKs). Ever since GRKs were first identified, investigators have sought to determine which structural features of GRKs are used to select for the agonist-bound states of GPCRs and how this binding event in turn enhances GRK catalytic activity. Despite a wealth of molecular information from high-resolution crystal structures of GRKs, the mechanisms driving activation have remained elusive, in part because the GRK N-terminus and active site tether region, previously proposed to serve as a receptor docking site and to be key to kinase domain closure, are often disordered or adopt inconsistent conformations. However, two recent studies have implicated other regions of GRKs as being involved in direct interactions with active GPCRs. Atomic resolution structures of GPCR–GRK complexes would help refine these models but are, so far, lacking. Here, we assess three distinct models for how GRKs recognize activated GPCRs, discuss limitations in the approaches used to generate them, and then experimentally test a hypothetical GPCR interaction site in GRK2 suggested by the two newest models.
Collapse
|
17
|
Targeting GRK5 for Treating Chronic Degenerative Diseases. Int J Mol Sci 2021; 22:ijms22041920. [PMID: 33671974 PMCID: PMC7919044 DOI: 10.3390/ijms22041920] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 12/27/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are the largest family of cell-surface receptors and they are responsible for the transduction of extracellular signals, regulating almost all aspects of mammalian physiology. These receptors are specifically regulated by a family of serine/threonine kinases, called GPCR kinases (GRKs). Given the biological role of GPCRs, it is not surprising that GRKs are also involved in several pathophysiological processes. Particular importance is emerging for GRK5, which is a multifunctional protein, expressed in different cell types, and it has been found located in single or multiple subcellular compartments. For instance, when anchored to the plasma membrane, GRK5 exerts its canonical function, regulating GPCRs. However, under certain conditions (e.g., pro-hypertrophic stimuli), GRK5 translocates to the nucleus of cells where it can interact with non-GPCR-related proteins as well as DNA itself to promote “non-canonical” signaling, including gene transcription. Importantly, due to these actions, several studies have demonstrated that GRK5 has a pivotal role in the pathogenesis of chronic-degenerative disorders. This is true in the cardiac cells, tumor cells, and neurons. For this reason, in this review article, we will inform the readers of the most recent evidence that supports the importance of targeting GRK5 to prevent the development or progression of cancer, cardiovascular, and neurological diseases.
Collapse
|
18
|
Bledzka KM, Manaserh IH, Grondolsky J, Pfleger J, Roy R, Gao E, Chuprun JK, Koch WJ, Schumacher SM. A peptide of the amino-terminus of GRK2 induces hypertrophy and yet elicits cardioprotection after pressure overload. J Mol Cell Cardiol 2021; 154:137-153. [PMID: 33548241 DOI: 10.1016/j.yjmcc.2021.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 12/14/2020] [Accepted: 01/11/2021] [Indexed: 12/13/2022]
Abstract
G protein-coupled receptor (GPCR) kinase 2 (GRK2) expression and activity are elevated early on in response to several forms of cardiovascular stress and are a hallmark of heart failure. Interestingly, though, in addition to its well-characterized role in regulating GPCRs, mounting evidence suggests a GRK2 "interactome" that underlies a great diversity in its functional roles. Several such GRK2 interacting partners are important for adaptive and maladaptive myocyte growth; therefore, an understanding of domain-specific interactions with signaling and regulatory molecules could lead to novel targets for heart failure therapy. Herein, we subjected transgenic mice with cardiac restricted expression of a short, amino terminal fragment of GRK2 (βARKnt) to pressure overload and found that unlike their littermate controls or previous GRK2 fragments, they exhibited an increased left ventricular wall thickness and mass prior to cardiac stress that underwent proportional hypertrophic growth to controls after acute pressure overload. Importantly, despite this enlarged heart, βARKnt mice did not undergo the expected transition to heart failure observed in controls. Further, βARKnt expression limited adverse left ventricular remodeling and increased cell survival signaling. Proteomic analysis to identify βARKnt binding partners that may underlie the improved cardiovascular phenotype uncovered a selective functional interaction of both endogenous GRK2 and βARKnt with AKT substrate of 160 kDa (AS160). AS160 has emerged as a key downstream regulator of insulin signaling, integrating physiological and metabolic cues to couple energy demand to membrane recruitment of Glut4. Our preliminary data indicate that in βARKnt mice, cardiomyocyte insulin signaling is improved during stress, with a coordinate increase in spare respiratory activity and ATP production without metabolite switching. Surprisingly, these studies also revealed a significant decrease in gonadal fat weight, equivalent to human abdominal fat, in male βARKnt mice at baseline and following cardiac stress. These data suggest that the enhanced AS160-mediated signaling in the βARKnt mice may ameliorate pathological cardiac remodeling through direct modulation of insulin signaling within cardiomyocytes, and translate these to beneficial effects on systemic metabolism.
Collapse
Affiliation(s)
- Kamila M Bledzka
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Iyad H Manaserh
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jessica Grondolsky
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jessica Pfleger
- Center for Translational Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Rajika Roy
- Center for Translational Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Erhe Gao
- Center for Translational Medicine, Temple University, Philadelphia, PA 19140, USA
| | - J Kurt Chuprun
- Center for Translational Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Walter J Koch
- Center for Translational Medicine, Temple University, Philadelphia, PA 19140, USA; Department of Pharmacology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Sarah M Schumacher
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| |
Collapse
|
19
|
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: 50] [Impact Index Per Article: 12.5] [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.
Collapse
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
| |
Collapse
|
20
|
Biased GPCR signaling: Possible mechanisms and inherent limitations. Pharmacol Ther 2020; 211:107540. [PMID: 32201315 DOI: 10.1016/j.pharmthera.2020.107540] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/17/2020] [Indexed: 02/06/2023]
Abstract
G protein-coupled receptors (GPCRs) are targeted by about a third of clinically used drugs. Many GPCRs couple to more than one type of heterotrimeric G proteins, become phosphorylated by any of several different GRKs, and then bind one or more types of arrestin. Thus, classical therapeutically active drugs simultaneously initiate several branches of signaling, some of which are beneficial, whereas others result in unwanted on-target side effects. The development of novel compounds to selectively channel the signaling into the desired direction has the potential to become a breakthrough in health care. However, there are natural and technological hurdles that must be overcome. The fact that most GPCRs are subject to homologous desensitization, where the active receptor couples to G proteins, is phosphorylated by GRKs, and then binds arrestins, suggest that in most cases the GPCR conformations that facilitate their interactions with these three classes of binding partners significantly overlap. Thus, while partner-specific conformations might exist, they are likely low-probability states. GPCRs are inherently flexible, which suggests that complete bias is highly unlikely to be feasible: in the conformational ensemble induced by any ligand, there would be some conformations facilitating receptor coupling to unwanted partners. Things are further complicated by the fact that virtually every cell expresses numerous G proteins, several GRK subtypes, and two non-visual arrestins with distinct signaling capabilities. Finally, novel screening methods for measuring ligand bias must be devised, as the existing methods are not specific for one particular branch of signaling.
Collapse
|
21
|
Min X, Zhang X, Sun N, Acharya S, Kim KM. Mdm2-mediated ubiquitination of PKCβII in the nucleus mediates clathrin-mediated endocytic activity. Biochem Pharmacol 2019; 170:113675. [DOI: 10.1016/j.bcp.2019.113675] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 10/16/2019] [Indexed: 11/30/2022]
|
22
|
Abstract
G protein-coupled receptors (GPCRs) are critical cellular sensors that mediate numerous physiological processes. In the heart, multiple GPCRs are expressed on various cell types, where they coordinate to regulate cardiac function by modulating critical processes such as contractility and blood flow. Under pathological settings, these receptors undergo aberrant changes in expression levels, localization and capacity to couple to downstream signalling pathways. Conventional therapies for heart failure work by targeting GPCRs, such as β-adrenergic receptor and angiotensin II receptor antagonists. Although these treatments have improved patient survival, heart failure remains one of the leading causes of mortality worldwide. GPCR kinases (GRKs) are responsible for GPCR phosphorylation and, therefore, desensitization and downregulation of GPCRs. In this Review, we discuss the GPCR signalling pathways and the GRKs involved in the pathophysiology of heart disease. Given that increased expression and activity of GRK2 and GRK5 contribute to the loss of contractile reserve in the stressed and failing heart, inhibition of overactive GRKs has been proposed as a novel therapeutic approach to treat heart failure.
Collapse
|
23
|
de Hoog E, Lukewich MK, Spencer GE. Retinoid receptor-based signaling plays a role in voltage-dependent inhibition of invertebrate voltage-gated Ca 2+ channels. J Biol Chem 2019; 294:10076-10093. [PMID: 31048374 DOI: 10.1074/jbc.ra118.006444] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 04/30/2019] [Indexed: 01/04/2023] Open
Abstract
The retinoic acid receptor (RAR) and retinoid X receptor (RXR) mediate the cellular effects of retinoids (derivatives of vitamin A). Both RAR and RXR signaling events are implicated in hippocampal synaptic plasticity. Furthermore, retinoids can interact with calcium signaling during homeostatic plasticity. We recently provided evidence that retinoids attenuate calcium current (I Ca) through neuronal voltage-gated calcium channels (VGCCs). We now examined the possibility that constitutive activity of neuronal RXR and/or RAR alters calcium influx via the VGCCs. We found that in neurons of the mollusk Lymnaea stagnalis, two different RXR antagonists (PA452 and HX531) had independent and opposing effects on I Ca that were also time-dependent; whereas the RXR pan-antagonist PA452 enhanced I Ca, HX531 reduced I Ca Interestingly, this effect of HX531 occurred through voltage-dependent inhibition of VGCCs, a phenomenon known to influence neurotransmitter release from neurons. This inhibition appeared to be independent of G proteins and was largely restricted to Cav2 Ca2+ channels. Of note, an RAR pan-antagonist, LE540, also inhibited I Ca but produced G protein-dependent, voltage-dependent inhibition of VGCCs. These findings provide evidence that retinoid receptors interact with G proteins in neurons and suggest mechanisms by which retinoids might affect synaptic calcium signaling.
Collapse
Affiliation(s)
- Eric de Hoog
- From the Department of Biological Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Mark K Lukewich
- From the Department of Biological Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Gaynor E Spencer
- From the Department of Biological Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| |
Collapse
|
24
|
Gurevich VV, Gurevich EV. GPCR Signaling Regulation: The Role of GRKs and Arrestins. Front Pharmacol 2019; 10:125. [PMID: 30837883 PMCID: PMC6389790 DOI: 10.3389/fphar.2019.00125] [Citation(s) in RCA: 330] [Impact Index Per Article: 66.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/31/2019] [Indexed: 12/13/2022] Open
Abstract
Every animal species expresses hundreds of different G protein-coupled receptors (GPCRs) that respond to a wide variety of external stimuli. GPCRs-driven signaling pathways are involved in pretty much every physiological function and in many pathologies. Therefore, GPCRs are targeted by about a third of clinically used drugs. The signaling of most GPCRs via G proteins is terminated by the phosphorylation of active receptor by specific kinases (GPCR kinases, or GRKs) and subsequent binding of arrestin proteins, that selectively recognize active phosphorylated receptors. In addition, GRKs and arrestins play a role in multiple signaling pathways in the cell, both GPCR-initiated and receptor-independent. Here we focus on the mechanisms of GRK- and arrestin-mediated regulation of GPCR signaling, which includes homologous desensitization and redirection of signaling to additional pathways by bound arrestins.
Collapse
Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| |
Collapse
|
25
|
Hendrickx JO, van Gastel J, Leysen H, Santos-Otte P, Premont RT, Martin B, Maudsley S. GRK5 - A Functional Bridge Between Cardiovascular and Neurodegenerative Disorders. Front Pharmacol 2018; 9:1484. [PMID: 30618771 PMCID: PMC6304357 DOI: 10.3389/fphar.2018.01484] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 12/03/2018] [Indexed: 12/15/2022] Open
Abstract
Complex aging-triggered disorders are multifactorial programs that comprise a myriad of alterations in interconnected protein networks over a broad range of tissues. It is evident that rather than being randomly organized events, pathophysiologies that possess a strong aging component such as cardiovascular diseases (hypertensions, atherosclerosis, and vascular stiffening) and neurodegenerative conditions (dementia, Alzheimer's disease, mild cognitive impairment, Parkinson's disease), in essence represent a subtly modified version of the intricate molecular programs already in place for normal aging. To control such multidimensional activities there are layers of trophic protein control across these networks mediated by so-called "keystone" proteins. We propose that these "keystones" coordinate and interconnect multiple signaling pathways to control whole somatic activities such as aging-related disease etiology. Given its ability to control multiple receptor sensitivities and its broad protein-protein interactomic nature, we propose that G protein coupled receptor kinase 5 (GRK5) represents one of these key network controllers. Considerable data has emerged, suggesting that GRK5 acts as a bridging factor, allowing signaling regulation in pathophysiological settings to control the connectivity between both the cardiovascular and neurophysiological complications of aging.
Collapse
Affiliation(s)
- Jhana O. Hendrickx
- Department of Biomedical Science, University of Antwerp, Antwerp, Belgium
- Center for Molecular Neurology, University of Antwerp – Flanders Institute for Biotechnology (VIB), Antwerp, Belgium
| | - Jaana van Gastel
- Department of Biomedical Science, University of Antwerp, Antwerp, Belgium
- Center for Molecular Neurology, University of Antwerp – Flanders Institute for Biotechnology (VIB), Antwerp, Belgium
| | - Hanne Leysen
- Department of Biomedical Science, University of Antwerp, Antwerp, Belgium
- Center for Molecular Neurology, University of Antwerp – Flanders Institute for Biotechnology (VIB), Antwerp, Belgium
| | - Paula Santos-Otte
- Institute of Biophysics, Humboldt-Universitat zu Berlin, Berlin, Germany
| | - Richard T. Premont
- Harrington Discovery Institute, Case Western Reserve University, Cleveland, GA, United States
| | - Bronwen Martin
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Antwerp, Belgium
| | - Stuart Maudsley
- Department of Biomedical Science, University of Antwerp, Antwerp, Belgium
- Center for Molecular Neurology, University of Antwerp – Flanders Institute for Biotechnology (VIB), Antwerp, Belgium
| |
Collapse
|
26
|
Abstract
G protein-coupled receptor kinases (GRKs) are classically known for their role in regulating the activity of the largest known class of membrane receptors, which influence diverse biological processes in every cell type in the human body. As researchers have tried to uncover how this family of kinases, containing only 7 members, achieves selective and coordinated control of receptors, they have uncovered a growing number of noncanonical activities for these kinases. These activities include phosphorylation of nonreceptor targets and kinase-independent molecular interactions. In particular, GRK2, GRK3, and GRK5 are the predominant members expressed in the heart. Their canonical and noncanonical actions within cardiac and other tissues have significant implications for cardiovascular function in healthy animals and for the development and progression of disease. This review summarizes what is currently known regarding the activity of these kinases, and particularly the role of GRK2 and GRK5 in the molecular alterations that occur during heart failure. This review further highlights areas of GRK regulation that remain poorly understood and how they may represent novel targets for therapeutic development.
Collapse
|
27
|
Pack TF, Orlen MI, Ray C, Peterson SM, Caron MG. The dopamine D2 receptor can directly recruit and activate GRK2 without G protein activation. J Biol Chem 2018; 293:6161-6171. [PMID: 29487132 DOI: 10.1074/jbc.ra117.001300] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/13/2018] [Indexed: 01/11/2023] Open
Abstract
The dopamine D2 receptor (D2R) is a G protein-coupled receptor (GPCR) that is critical for many central nervous system functions. The D2R carries out these functions by signaling through two transducers: G proteins and β-arrestins (βarrs). Selectively engaging either the G protein or βarr pathway may be a way to improve drugs targeting GPCRs. The current model of GPCR signal transduction posits a chain of events where G protein activation ultimately leads to βarr recruitment. GPCR kinases (GRKs), which are regulated by G proteins and whose kinase action facilitates βarr recruitment, bridge these pathways. Therefore, βarr recruitment appears to be intimately tied to G protein activation via GRKs. Here we sought to understand how GRK2 action at the D2R would be disrupted when G protein activation is eliminated and the effect of this on βarr recruitment. We used two recently developed biased D2R mutants that can preferentially interact either with G proteins or βarrs as well as a βarr-biased D2R ligand, UNC9994. With these functionally selective tools, we investigated the mechanism whereby the βarr-preferring D2R achieves βarr pathway activation in the complete absence of G protein activation. We describe how direct, G protein-independent recruitment of GRK2 drives interactions at the βarr-preferring D2R and also contributes to βarr recruitment at the WT D2R. Additionally, we found an additive interaction between the βarr-preferring D2R mutant and UNC9994. These results reveal that the D2R can directly recruit GRK2 without G protein activation and that this mechanism may have relevance to achieving βarr-biased signaling.
Collapse
Affiliation(s)
- Thomas F Pack
- From the Departments of Pharmacology and Cancer Biology.,Cell Biology
| | | | | | | | - Marc G Caron
- Cell Biology, .,Neurobiology, and.,Medicine, Duke University Medical Center, Duke University School of Medicine, Durham, North Carolina 27710
| |
Collapse
|
28
|
Cannavo A, Komici K, Bencivenga L, D'amico ML, Gambino G, Liccardo D, Ferrara N, Rengo G. GRK2 as a therapeutic target for heart failure. Expert Opin Ther Targets 2017; 22:75-83. [PMID: 29166798 DOI: 10.1080/14728222.2018.1406925] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION G protein-coupled receptor (GPCR) kinase-2 (GRK2) is a regulator of GPCRs, in particular β-adrenergic receptors (ARs), and as demonstrated by decades of investigation, it has a pivotal role in the development and progression of cardiovascular disease, like heart failure (HF). Indeed elevated levels and activity of this kinase are able to promote the dysfunction of both cardiac and adrenal α- and β-ARs and to dysregulate other protective signaling pathway, such as sphingosine 1-phospate and insulin. Moreover, recent discoveries suggest that GRK2 can signal independently from GPCRs, in a 'non-canonical' manner, via interaction with non-GPCR molecule or via its mitochondrial localization. Areas covered: Based on this premise, GRK2 inhibition or its genetic deletion has been tested in several disparate animal models of cardiovascular disease, showing to protect the heart from adverse remodeling and dysfunction. Expert opinion: HF is one of the leading cause of death worldwide with enormous health care costs. For this reason, the identification of new therapeutic targets like GRK2 and strategies such as its inhibition represents a new hope in the fight against HF development and progression. Herein, we will update the readers about the 'state-of-art' of GRK2 inhibition as a potent therapeutic strategy in HF.
Collapse
Affiliation(s)
- Alessandro Cannavo
- a Center for Translational Medicine , Temple University Lewis Katz School of Medicine , Philadelphia , PA , USA.,b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy
| | - Klara Komici
- b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy
| | - Leonardo Bencivenga
- b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy
| | - Maria Loreta D'amico
- c Istituti Clinici Scientifici Maugeri SpA Società Benefit , Telese Terme Institute , Benevento , Italy
| | - Giuseppina Gambino
- c Istituti Clinici Scientifici Maugeri SpA Società Benefit , Telese Terme Institute , Benevento , Italy
| | - Daniela Liccardo
- b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy
| | - Nicola Ferrara
- b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy.,c Istituti Clinici Scientifici Maugeri SpA Società Benefit , Telese Terme Institute , Benevento , Italy
| | - Giuseppe Rengo
- b Dpt Translational Medical Sciences , Federico II University of Naples , Naples , Italy.,c Istituti Clinici Scientifici Maugeri SpA Società Benefit , Telese Terme Institute , Benevento , Italy
| |
Collapse
|
29
|
Wang J, Hanada K, Staus DP, Makara MA, Dahal GR, Chen Q, Ahles A, Engelhardt S, Rockman HA. Gα i is required for carvedilol-induced β 1 adrenergic receptor β-arrestin biased signaling. Nat Commun 2017; 8:1706. [PMID: 29167435 PMCID: PMC5700200 DOI: 10.1038/s41467-017-01855-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 10/19/2017] [Indexed: 12/12/2022] Open
Abstract
The β1 adrenergic receptor (β1AR) is recognized as a classical Gαs-coupled receptor. Agonist binding not only initiates G protein-mediated signaling but also signaling through the multifunctional adapter protein β-arrestin. Some βAR ligands, such as carvedilol, stimulate βAR signaling preferentially through β-arrestin, a concept known as β-arrestin-biased agonism. Here, we identify a signaling mechanism, unlike that previously known for any Gαs-coupled receptor, whereby carvedilol induces the transition of the β1AR from a classical Gαs-coupled receptor to a Gαi-coupled receptor stabilizing a distinct receptor conformation to initiate β-arrestin-mediated signaling. Recruitment of Gαi is not induced by any other βAR ligand screened, nor is it required for β-arrestin-bias activated by the β2AR subtype of the βAR family. Our findings demonstrate a previously unrecognized role for Gαi in β1AR signaling and suggest that the concept of β-arrestin-bias may need to be refined to incorporate the selective bias of receptors towards distinct G protein subtypes.
Collapse
Affiliation(s)
- Jialu Wang
- Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Kenji Hanada
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Dean P Staus
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Michael A Makara
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Giri Raj Dahal
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Qiang Chen
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Andrea Ahles
- Institute of Pharmacology and Toxicology, Technical University of Munich, Munich, 80802, Germany
| | - Stefan Engelhardt
- Institute of Pharmacology and Toxicology, Technical University of Munich, Munich, 80802, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, 80802, Germany
| | - Howard A Rockman
- Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA. .,Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA. .,Departments of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.
| |
Collapse
|
30
|
Topalidou I, Cooper K, Pereira L, Ailion M. Dopamine negatively modulates the NCA ion channels in C. elegans. PLoS Genet 2017; 13:e1007032. [PMID: 28968387 PMCID: PMC5638609 DOI: 10.1371/journal.pgen.1007032] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 10/12/2017] [Accepted: 09/18/2017] [Indexed: 02/07/2023] Open
Abstract
The NALCN/NCA ion channel is a cation channel related to voltage-gated sodium and calcium channels. NALCN has been reported to be a sodium leak channel with a conserved role in establishing neuronal resting membrane potential, but its precise cellular role and regulation are unclear. The Caenorhabditis elegans orthologs of NALCN, NCA-1 and NCA-2, act in premotor interneurons to regulate motor circuit activity that sustains locomotion. Recently we found that NCA-1 and NCA-2 are activated by a signal transduction pathway acting downstream of the heterotrimeric G protein Gq and the small GTPase Rho. Through a forward genetic screen, here we identify the GPCR kinase GRK-2 as a new player affecting signaling through the Gq-Rho-NCA pathway. Using structure-function analysis, we find that the GPCR phosphorylation and membrane association domains of GRK-2 are required for its function. Genetic epistasis experiments suggest that GRK-2 acts on the D2-like dopamine receptor DOP-3 to inhibit Go signaling and positively modulate NCA-1 and NCA-2 activity. Through cell-specific rescuing experiments, we find that GRK-2 and DOP-3 act in premotor interneurons to modulate NCA channel function. Finally, we demonstrate that dopamine, through DOP-3, negatively regulates NCA activity. Thus, this study identifies a pathway by which dopamine modulates the activity of the NCA channels.
Collapse
Affiliation(s)
- Irini Topalidou
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
- * E-mail: (IT); (MA)
| | - Kirsten Cooper
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Laura Pereira
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, New York, United States of America
| | - Michael Ailion
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
- * E-mail: (IT); (MA)
| |
Collapse
|
31
|
Purcell RH, Toro C, Gahl WA, Hall RA. A disease-associated mutation in the adhesion GPCR BAI2 (ADGRB2) increases receptor signaling activity. Hum Mutat 2017; 38:1751-1760. [PMID: 28891236 DOI: 10.1002/humu.23336] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/01/2017] [Accepted: 09/03/2017] [Indexed: 12/15/2022]
Abstract
Mutations in G protein-coupled receptors (GPCRs) that increase constitutive signaling activity can cause human disease. A de novo C-terminal mutation (R1465W) in the adhesion GPCR BAI2 (also known as ADGRB2) was identified in a patient suffering from progressive spastic paraparesis and other neurological symptoms. In vitro studies revealed that this mutation strongly increases the constitutive signaling activity of an N-terminally cleaved form of BAI2, which represents the activated form of the receptor. Further studies dissecting the mechanism(s) underling this effect revealed that wild-type BAI2 primarily couples to Gαz , with the R1465W mutation conferring increased coupling to Gαi . The R1465W mutation also increases the total and surface expression of BAI2. The mutation has no effect on receptor binding to β-arrestins, but does perturb binding to the endocytic protein endophilin A1, identified here as a novel interacting partner for BAI2. These studies provide new insights into the signaling capabilities of the adhesion GPCR BAI2/ADGRB2 and shed light on how an apparent gain-of-function mutation to the receptor's C-terminus may lead to human disease.
Collapse
Affiliation(s)
- Ryan H Purcell
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Office of the Director, NIH, Bethesda, Maryland
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Office of the Director, NIH, Bethesda, Maryland
| | - Randy A Hall
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia
| |
Collapse
|
32
|
O'Hayre M, Eichel K, Avino S, Zhao X, Steffen DJ, Feng X, Kawakami K, Aoki J, Messer K, Sunahara R, Inoue A, von Zastrow M, Gutkind JS. Genetic evidence that β-arrestins are dispensable for the initiation of β 2-adrenergic receptor signaling to ERK. Sci Signal 2017. [PMID: 28634209 DOI: 10.1126/scisignal.aal3395] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The β2-adrenergic receptor (β2AR) has provided a paradigm to elucidate how G protein-coupled receptors (GPCRs) control intracellular signaling, including the discovery that β-arrestins, which bind to ligand-activated GPCRs, are central for GPCR function. We used genome editing, conditional gene deletion, and small interfering RNAs (siRNAs) to determine the roles of β-arrestin 1 (β-arr1) and β-arr2 in β2AR internalization, trafficking, and signaling to ERK. We found that only β-arr2 was essential for β2AR internalization. Unexpectedly, β-arr1 and β-arr2 and receptor internalization were dispensable for ERK activation. Instead, β2AR signaled through Gαs and Gβγ subunits through a pathway that involved the tyrosine kinase SRC, the adaptor protein SHC, the guanine nucleotide exchange factor SOS, the small GTPase RAS, and the kinases RAF and MEK, which led to ERK activation. These findings provide a molecular framework for β2AR signaling through β-arrestin-independent pathways in key physiological functions and under pathological conditions.
Collapse
Affiliation(s)
- Morgan O'Hayre
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20852, USA
| | - Kelsie Eichel
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Silvia Avino
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20852, USA.,Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Via Pietro Bucci, 87036 Rende (CS), Italy
| | - Xuefeng Zhao
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20852, USA.,Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.,State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Dana J Steffen
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Xiaodong Feng
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20852, USA.,Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kouki Kawakami
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578, Japan.,Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Karen Messer
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Roger Sunahara
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578, Japan.,Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama 332-0012, Japan
| | - Mark von Zastrow
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94158, USA.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - J Silvio Gutkind
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20852, USA. .,Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| |
Collapse
|
33
|
Rajagopal S, Shenoy SK. GPCR desensitization: Acute and prolonged phases. Cell Signal 2017; 41:9-16. [PMID: 28137506 DOI: 10.1016/j.cellsig.2017.01.024] [Citation(s) in RCA: 208] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 01/25/2017] [Indexed: 01/04/2023]
Abstract
G protein-coupled receptors (GPCRs) transduce a wide array of extracellular signals and regulate virtually every aspect of physiology. While GPCR signaling is essential, overstimulation can be deleterious, resulting in cellular toxicity or uncontrolled cellular growth. Accordingly, nature has developed a number of mechanisms for limiting GPCR signaling, which are broadly referred to as desensitization, and refer to a decrease in response to repeated or continuous stimulation. Short-term desensitization occurs over minutes, and is primarily associated with β-arrestins preventing G protein interaction with a GPCR. Longer-term desensitization, referred to as downregulation, occurs over hours to days, and involves receptor internalization into vesicles, degradation in lysosomes and decreased receptor mRNA levels through unclear mechanisms. Phosphorylation of the receptor by GPCR kinases (GRKs) and the recruitment of β-arrestins is critical to both these short- and long-term desensitization mechanisms. In addition to phosphorylation, both the GPCR and β-arrestins are modified post-translationally in several ways, including by ubiquitination. For many GPCRs, receptor ubiquitination promotes degradation of agonist-activated receptors in the lysosomes. Other proteins also play important roles in desensitization, including phosphodiesterases, RGS family proteins and A-kinase-anchoring proteins. Together, this intricate network of kinases, ubiquitin ligases, and adaptor proteins orchestrate the acute and prolonged desensitization of GPCRs.
Collapse
Affiliation(s)
| | - Sudha K Shenoy
- Department of Medicine (Cardiology), Durham, NC, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.
| |
Collapse
|
34
|
Targeting GPCR-Gβγ-GRK2 signaling as a novel strategy for treating cardiorenal pathologies. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1883-1892. [PMID: 28130200 DOI: 10.1016/j.bbadis.2017.01.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 02/06/2023]
Abstract
The pathologic crosstalk between the heart and kidney is known as cardiorenal syndrome (CRS). While the specific mechanisms underlying this crosstalk remain poorly understood, CRS is associated with exacerbated dysfunction of either or both organs and reduced survival. Maladaptive fibrotic remodeling is a key component of both heart and kidney failure pathogenesis and progression. G-protein coupled receptor (GPCR) signaling is a crucial regulator of cardiovascular and renal function. Chronic/pathologic GPCR signaling elicits the interaction of the G-protein Gβγ subunit with GPCR kinase 2 (GRK2), targeting the receptor for internalization, scaffolding to pathologic signals, and receptor degradation. Targeting this pathologic Gβγ-GRK2 interaction has been suggested as a possible strategy for the treatment of HF. In the current review, we discuss recent updates in understanding the role of GPCR-Gβγ-GRK2 signaling as a crucial mediator of maladaptive organ remodeling detected in HF and kidney dysfunction, with specific attention to small molecule-mediated inhibition of pathologic Gβγ-GRK2 interactions. Further, we explore the potential of GPCR-Gβγ-GRK2 signaling as a possible therapeutic target for cardiorenal pathologies.
Collapse
|
35
|
Klayman LM, Wedegaertner PB. Inducible Inhibition of Gβγ Reveals Localization-dependent Functions at the Plasma Membrane and Golgi. J Biol Chem 2016; 292:1773-1784. [PMID: 27994056 DOI: 10.1074/jbc.m116.750430] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 12/16/2016] [Indexed: 01/28/2023] Open
Abstract
Heterotrimeric G proteins signal at a variety of endomembrane locations, in addition to their canonical function at the cytoplasmic surface of the plasma membrane (PM), where they are activated by cell surface G protein-coupled receptors. Here we focus on βγ signaling at the Golgi, where βγ activates a signaling cascade, ultimately resulting in vesicle fission from the trans-Golgi network (TGN). To develop a novel molecular tool for inhibiting endogenous βγ in a spatial-temporal manner, we take advantage of a lipid association mutant of the widely used βγ inhibitor GRK2ct (GRK2ct-KERE) and the FRB/FKBP heterodimerization system. We show that GRK2ct-KERE cannot inhibit βγ function when expressed in cells, but recruitment to a specific membrane location recovers the ability of GRK2ct-KERE to inhibit βγ signaling. PM-recruited GRK2ct-KERE inhibits lysophosphatidic acid-induced phosphorylation of Akt, whereas Golgi-recruited GRK2ct-KERE inhibits cargo transport from the TGN to the PM. Moreover, we show that Golgi-recruited GRK2ct-KERE inhibits model basolaterally targeted but not apically targeted cargo delivery, for both PM-destined and secretory cargo, providing the first evidence of selectivity in terms of cargo transport regulated by βγ. Last, we show that Golgi fragmentation induced by ilimaquinone and nocodazole is blocked by βγ inhibition, demonstrating that βγ is a key regulator of multiple pathways that impact Golgi morphology. Thus, we have developed a new molecular tool, recruitable GRK2ct-KERE, to modulate βγ signaling at specific subcellular locations, and we demonstrate novel cargo selectivity for βγ regulation of TGN to PM transport and a novel role for βγ in mediating Golgi fragmentation.
Collapse
Affiliation(s)
- Lauren M Klayman
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Philip B Wedegaertner
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107.
| |
Collapse
|
36
|
G-protein-coupled receptor kinase 2 terminates G-protein-coupled receptor function in steroid hormone 20-hydroxyecdysone signaling. Sci Rep 2016; 6:29205. [PMID: 27412951 PMCID: PMC4944123 DOI: 10.1038/srep29205] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/16/2016] [Indexed: 12/26/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) transmit extracellular signals across the cell membrane. GPCR kinases (GRKs) desensitize GPCR signals in the cell membrane. However, the role and mechanism of GRKs in the desensitization of steroid hormone signaling are unclear. In this study, we propose that GRK2 is phosphorylated by protein kinase C (PKC) in response to induction by the steroid hormone 20-hydroxyecdysone (20E), which determines its translocation to the cell membrane of the lepidopteran Helicoverpa armigera. GRK2 protein expression is increased during the metamorphic stage because of induction by 20E. Knockdown of GRK2 in larvae causes accelerated pupation, an increase in 20E-response gene expression, and advanced apoptosis and metamorphosis. 20E induces translocation of GRK2 from the cytoplasm to the cell membrane via steroid hormone ecdysone-responsive GPCR (ErGPCR-2). GRK2 is phosphorylated by PKC on serine 680 after induction by 20E, which leads to the translocation of GRK2 to the cell membrane. GRK2 interacts with ErGPCR-2. These data indicate that GRK2 terminates the ErGPCR-2 function in 20E signaling in the cell membrane by a negative feedback mechanism.
Collapse
|
37
|
Guccione M, Ettari R, Taliani S, Da Settimo F, Zappalà M, Grasso S. G-Protein-Coupled Receptor Kinase 2 (GRK2) Inhibitors: Current Trends and Future Perspectives. J Med Chem 2016; 59:9277-9294. [PMID: 27362616 DOI: 10.1021/acs.jmedchem.5b01939] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
G-protein-coupled receptor kinase 2 (GRK2) is a G-protein-coupled receptor kinase that is ubiquitously expressed in many tissues and regulates various intracellular mechanisms. The up- or down-regulation of GRK2 correlates with several pathological disorders. GRK2 plays an important role in the maintenance of heart structure and function; thus, this kinase is involved in many cardiovascular diseases. GRK2 up-regulation can worsen cardiac ischemia; furthermore, increased kinase levels occur during the early stages of heart failure and in hypertensive subjects. GRK2 up-regulation can lead to changes in the insulin signaling cascade, which can translate to insulin resistance. Increased GRK2 levels also correlate with the degree of cognitive impairment that is typically observed in Alzheimer's disease. This article reviews the most potent and selective GRK2 inhibitors that have been developed. We focus on their mechanism of action, inhibition profile, and structure-activity relationships to provide insight into the further development of GRK2 inhibitors as drug candidates.
Collapse
Affiliation(s)
- Manuela Guccione
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università degli Studi di Messina , Viale Annunziata, 98168 Messina, Italy
| | - Roberta Ettari
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università degli Studi di Messina , Viale Annunziata, 98168 Messina, Italy
| | - Sabrina Taliani
- Dipartimento di Farmacia, Università di Pisa , Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Federico Da Settimo
- Dipartimento di Farmacia, Università di Pisa , Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Maria Zappalà
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università degli Studi di Messina , Viale Annunziata, 98168 Messina, Italy
| | - Silvana Grasso
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università degli Studi di Messina , Viale Annunziata, 98168 Messina, Italy
| |
Collapse
|
38
|
Penela P. Chapter Three - Ubiquitination and Protein Turnover of G-Protein-Coupled Receptor Kinases in GPCR Signaling and Cellular Regulation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:85-140. [PMID: 27378756 DOI: 10.1016/bs.pmbts.2016.04.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
G-protein-coupled receptors (GPCRs) are responsible for regulating a wide variety of physiological processes, and distinct mechanisms for GPCR inactivation exist to guarantee correct receptor functionality. One of the widely used mechanisms is receptor phosphorylation by specific G-protein-coupled receptor kinases (GRKs), leading to uncoupling from G proteins (desensitization) and receptor internalization. GRKs and β-arrestins also participate in the assembly of receptor-associated multimolecular complexes, thus initiating alternative G-protein-independent signaling events. In addition, the abundant GRK2 kinase has diverse "effector" functions in cellular migration, proliferation, and metabolism homeostasis by means of the phosphorylation or interaction with non-GPCR partners. Altered expression of GRKs (particularly of GRK2 and GRK5) occurs during pathological conditions characterized by impaired GPCR signaling including inflammatory syndromes, cardiovascular disease, and tumor contexts. It is increasingly appreciated that different pathways governing GRK protein stability play a role in the modulation of kinase levels in normal and pathological conditions. Thus, enhanced GRK2 degradation by the proteasome pathway occurs upon GPCR stimulation, what allows cellular adaptation to chronic stimulation in a physiological setting. β-arrestins participate in this process by facilitating GRK2 phosphorylation by different kinases and by recruiting diverse E3 ubiquitin ligase to the receptor complex. Different proteolytic systems (ubiquitin-proteasome, calpains), chaperone activities and signaling pathways influence the stability of GRKs in different ways, thus endowing specificity to GPCR regulation as protein turnover of GRKs can be differentially affected. Therefore, modulation of protein stability of GRKs emerges as a versatile mechanism for feedback regulation of GPCR signaling and basic cellular processes.
Collapse
Affiliation(s)
- P Penela
- Department of Molecular Biology and Centre of Molecular Biology "Severo Ochoa" (CSIC-UAM), Madrid, Autonomous University of Madrid, Madrid, Spain; Spain Health Research Institute The Princesa, Madrid, Spain.
| |
Collapse
|
39
|
Vatter P, Schuhholz J, Koenig C, Pfreimer M, Moepps B. Ligand-dependent serum response factor activation by the human CC chemokine receptors CCR2a and CCR2b is mediated by G proteins of the Gqfamily. J Leukoc Biol 2016; 99:979-91. [DOI: 10.1189/jlb.2ma0815-386r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 01/13/2016] [Indexed: 12/31/2022] Open
|
40
|
Helmer D, Schmitz K. Peptides and Peptide Analogs to Inhibit Protein-Protein Interactions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 917:147-83. [PMID: 27236556 DOI: 10.1007/978-3-319-32805-8_8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Protein-protein interactions are governed by relatively few amino acid residues at the binding interface. Peptides derived from these protein regions may serve as mimics of one of the interaction partners in structural studies or as inhibitors to disrupt the respective interaction and investigate its biological consequences. Inhibitory peptides may also be lead structures for drug development if the respective protein-protein interaction is essential for a pathogen or disease mechanism. Binding peptides may be systematically derived from one of the binding partners or found in the screen of combinatorial peptide libraries. Molecular modelling based on structural data helps to refine existing peptides or even design novel binding peptides. This chapter gives an outline of the binding peptide discovery process and subsequent chemical modifications to further enhance affinity and specificity and to increase stability against degradation in vivo. Examples from the past three decades illustrate the great diversity of applications for protein binding peptides and peptide analogs.
Collapse
Affiliation(s)
- Dorothea Helmer
- Technische Universität Darmstadt, Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany
| | - Katja Schmitz
- Technische Universität Darmstadt, Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany.
| |
Collapse
|
41
|
Berecki G, Motin L, Adams DJ. Voltage-Gated R-Type Calcium Channel Inhibition via Human μ-, δ-, and κ-opioid Receptors Is Voltage-Independently Mediated by Gβγ Protein Subunits. Mol Pharmacol 2015; 89:187-96. [PMID: 26490245 DOI: 10.1124/mol.115.101154] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/19/2015] [Indexed: 01/07/2023] Open
Abstract
Elucidating the mechanisms that modulate calcium channels via opioid receptor activation is fundamental to our understanding of both pain perception and how opioids modulate pain. Neuronal voltage-gated N-type calcium channels (Cav2.2) are inhibited by activation of G protein-coupled opioid receptors (ORs). However, inhibition of R-type (Cav2.3) channels by μ- or κ-ORs is poorly defined and has not been reported for δ-ORs. To investigate such interactions, we coexpressed human μ-, δ-, or κ-ORs with human Cav2.3 or Cav2.2 in human embryonic kidney 293 cells and measured depolarization-activated Ba(2+) currents (IBa). Selective agonists of μ-, δ-, and κ-ORs inhibited IBa through Cav2.3 channels by 35%. Cav2.2 channels were inhibited to a similar extent by κ-ORs, but more potently (60%) via μ- and δ-ORs. Antagonists of δ- and κ-ORs potentiated IBa amplitude mediated by Cav2.3 and Cav2.2 channels. Consistent with G protein βγ (Gβγ) interaction, modulation of Cav2.2 was primarily voltage-dependent and transiently relieved by depolarizing prepulses. In contrast, Cav2.3 modulation was voltage-independent and unaffected by depolarizing prepulses. However, Cav2.3 inhibition was sensitive to pertussis toxin and to intracellular application of guanosine 5'-[β-thio]diphosphate trilithium salt and guanosine 5'-[γ-thio]triphosphate tetralithium salt. Coexpression of Gβγ-specific scavengers-namely, the carboxyl terminus of the G protein-coupled receptor kinase 2 or membrane-targeted myristoylated-phosducin-attenuated or abolished Cav2.3 modulation. Our study reveals the diversity of OR-mediated signaling at Cav2 channels and identifies neuronal Cav2.3 channels as potential targets for opioid analgesics. Their novel modulation is dependent on pre-existing OR activity and mediated by membrane-delimited Gβγ subunits in a voltage-independent manner.
Collapse
Affiliation(s)
- Géza Berecki
- Health Innovations Research Institute, RMIT University, Melbourne, Victoria, Australia
| | - Leonid Motin
- Health Innovations Research Institute, RMIT University, Melbourne, Victoria, Australia
| | - David J Adams
- Health Innovations Research Institute, RMIT University, Melbourne, Victoria, Australia
| |
Collapse
|
42
|
Sato PY, Chuprun JK, Schwartz M, Koch WJ. The evolving impact of g protein-coupled receptor kinases in cardiac health and disease. Physiol Rev 2015; 95:377-404. [PMID: 25834229 PMCID: PMC4551214 DOI: 10.1152/physrev.00015.2014] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are important regulators of various cellular functions via activation of intracellular signaling events. Active GPCR signaling is shut down by GPCR kinases (GRKs) and subsequent β-arrestin-mediated mechanisms including phosphorylation, internalization, and either receptor degradation or resensitization. The seven-member GRK family varies in their structural composition, cellular localization, function, and mechanism of action (see sect. II). Here, we focus our attention on GRKs in particular canonical and novel roles of the GRKs found in the cardiovascular system (see sects. III and IV). Paramount to overall cardiac function is GPCR-mediated signaling provided by the adrenergic system. Overstimulation of the adrenergic system has been highly implicated in various etiologies of cardiovascular disease including hypertension and heart failure. GRKs acting downstream of heightened adrenergic signaling appear to be key players in cardiac homeostasis and disease progression, and herein we review the current data on GRKs related to cardiac disease and discuss their potential in the development of novel therapeutic strategies in cardiac diseases including heart failure.
Collapse
Affiliation(s)
- Priscila Y Sato
- Center for Translational Medicine and Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania; and Advanced Institutes of Convergence Technology, Suwon, South Korea
| | - J Kurt Chuprun
- Center for Translational Medicine and Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania; and Advanced Institutes of Convergence Technology, Suwon, South Korea
| | - Mathew Schwartz
- Center for Translational Medicine and Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania; and Advanced Institutes of Convergence Technology, Suwon, South Korea
| | - Walter J Koch
- Center for Translational Medicine and Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania; and Advanced Institutes of Convergence Technology, Suwon, South Korea
| |
Collapse
|
43
|
Abstract
SIGNIFICANCE Heart failure (HF) is a common end point for many underlying cardiovascular diseases. Down-regulation and desensitization of β-adrenergic receptors (β-AR) caused by G-protein-coupled receptor (GPCR) kinase 2 (GRK2) are prominent features of HF. Recent Advances and Critical Issues: Significant progress has been made to understand the pathological role of GRK2 in the heart both as a GPCR kinase and as a molecule that can exert GPCR-independent effects. Inhibition of cardiac GRK2 has proved to be therapeutic in the failing heart and may offer synergistic and additional benefits to β-blocker therapy. However, the mechanisms of how GRK2 directly contributes to the pathogenesis of HF need further investigation, and additional verification of the mechanistic details are needed before GRK2 inhibition can be used for the treatment of HF. FUTURE DIRECTIONS The newly identified characteristics of GRK2, including the S-nitrosylation of GRK2 and the localization of GRK2 on mitochondria, merit further investigation. They may contribute to it being a pro-death kinase and result in HF under stressed conditions through regulation of intracellular signaling, including cardiac reduction-oxidation (redox) balance. A thorough understanding of the functions of GRK2 in the heart is necessary in order to finalize it as a candidate for drug development.
Collapse
Affiliation(s)
- Zheng Maggie Huang
- Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine , Philadelphia, Pennsylvania
| | | | | | | |
Collapse
|
44
|
Roosterman D. Agonist-dependent and -independent dopamine-1-like receptor signalling differentially regulates downstream effectors. FEBS J 2014; 281:4792-804. [PMID: 25154512 DOI: 10.1111/febs.13018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 07/25/2014] [Accepted: 08/21/2014] [Indexed: 12/17/2022]
Abstract
De-regulation of energy metabolism by the dopaminergic system is linked to neurological diseases such as schizophrenia and bipolar disorder. Inverse agonists are thought to be more beneficial in treating neurological diseases than neutral antagonists, but only limited experimental data are available regarding the impact of constitutive signalling on energy metabolism. The aim of the present study was to assess the impact of constitutive dopamine-1 receptor (D1R) and dopamine-5 receptor (D5R) signalling on downstream targets in transiently and stably transfected HEK293T cells. The high constitutive activity of D5R was accompanied by increased Na(+)/H(+) exchanger (NHE) activity and accelerated glucose degradation due to increased transcription and translation of the Na, K-ATPase-α3 and NHE-2. Chronic treatment with an agonist increased the mRNA levels of the α2 Na,K-ATPase, NHE-2 and NHE-3. Constitutive D5R activation of a cAMP response element-based reporter was regulated by G protein-coupled receptor kinase 2, but this did not affect the cell-surface abundance of the receptor. Our data suggest that constitutive and agonist-induced activity of D5R differentially regulates the activity and expression of proteins.
Collapse
|
45
|
Philipp M, Berger IM, Just S, Caron MG. Overlapping and opposing functions of G protein-coupled receptor kinase 2 (GRK2) and GRK5 during heart development. J Biol Chem 2014; 289:26119-26130. [PMID: 25104355 DOI: 10.1074/jbc.m114.551952] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
G protein-coupled receptor kinases 2 (GRK2) and 5 (GRK5) are fundamental regulators of cardiac performance in adults but are less well characterized for their function in the hearts of embryos. GRK2 and -5 belong to different subfamilies and function as competitors in the control of certain receptors and signaling pathways. In this study, we used zebrafish to investigate whether the fish homologs of GRK2 and -5, Grk2/3 and Grk5, also have unique, complementary, or competitive roles during heart development. We found that they differentially regulate the heart rate of early embryos and equally facilitate heart function in older embryos and that both are required to develop proper cardiac morphology. A loss of Grk2/3 results in dilated atria and hypoplastic ventricles, and the hearts of embryos depleted in Grk5 present with a generalized atrophy. This Grk5 morphant phenotype was associated with an overall decrease of early cardiac progenitors as well as a reduction in the area occupied by myocardial progenitor cells. In the case of Grk2/3, the progenitor decrease was confined to a subset of precursor cells with a committed ventricular fate. We attempted to rescue the GRK loss-of-function heart phenotypes by downstream activation of Hedgehog signaling. The Grk2/3 loss-of-function embryos were rescued by this approach, but Grk5 embryos failed to respond. In summary, we found that GRK2 and GRK5 control cardiac function as well as morphogenesis during development although with different morphological outcomes.
Collapse
Affiliation(s)
- Melanie Philipp
- Institute of Biochemistry and Molecular Biology and Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Ina M Berger
- Department of Internal Medicine II-Cardiology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany and
| | - Steffen Just
- Department of Internal Medicine II-Cardiology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany and
| | - Marc G Caron
- Departments of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710; Departments of Medicine, and Duke University Medical Center, Durham, North Carolina 27710; Departments of Neurobiology, Duke University Medical Center, Durham, North Carolina 27710
| |
Collapse
|
46
|
Alexander LD, Ding Y, Alagarsamy S, Cui X. Angiotensin II stimulates fibronectin protein synthesis via a Gβγ/arachidonic acid-dependent pathway. Am J Physiol Renal Physiol 2014; 307:F287-302. [PMID: 24920755 DOI: 10.1152/ajprenal.00094.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
In rabbit proximal tubular cells, ANG II type 2-receptor (AT2)-induced arachidonic acid release is PLA2 coupled and dependent of G protein βγ (Gβγ) subunits. Moreover, ANG II activates ERK1/2 and transactivates EGFR via a c-Src-dependent mechanism. Arachidonic acid has been shown to mimic this effect, at least in part, by an undetermined mechanism. In this study, we determined the effects of ANG II on fibronectin expression in cultured rabbit proximal tubule cells and elucidated the signaling pathways associated with such expression. We found that ANG II and transfection of Gβγ subunits directly increased fibronectin protein expression, and this increase was inhibited by overexpression of β-adrenergic receptor kinase (βARK)-ct or DN-Src. Moreover, ANG II-induced fibronectin protein expression was significantly abrogated by the AT2 receptor antagonist PD123319. In addition, inhibition of cystolic PLA2 diminished ANG II-induced fibronectin expression. Endogenous arachidonic acid mimicked ANG II-induced fibronectin expression. We also found that overexpression of Gβγ subunits induced c-Src, ERK1/2, and EGFR tyrosine phosphorylation, which can be inhibited by overexpression of βARK-ct or DN-Src. Gβγ also induced c-Src SH2 domain association with the EGFR. Supporting these findings, in rabbit proximal tubular epithelium, immunoblot analysis indicated that βγ expression was significant. Interestingly, arachidonic acid- and eicosatetraenoic acid-induced responses were preserved in the presence of βARK-ct. This is the first report demonstrating the regulation of EGFR, ERK1/2, c-Src, and fibronectin by Gβγ subunits in renal epithelial cells. Moreover, this work demonstrates a role for Gβγ heterotrimeric proteins in ANG II, but not arachidonic acid, signaling in renal epithelial cells.
Collapse
Affiliation(s)
- Larry D Alexander
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona; and
| | - Yaxian Ding
- Division of Nephrology and Hypertension, Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, Cleveland, Ohio
| | - Suganthi Alagarsamy
- Division of Nephrology and Hypertension, Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, Cleveland, Ohio
| | - Xiaolan Cui
- Division of Nephrology and Hypertension, Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, Cleveland, Ohio
| |
Collapse
|
47
|
Kabbani N, Nordman JC, Corgiat BA, Veltri DP, Shehu A, Seymour VA, Adams DJ. Are nicotinic acetylcholine receptors coupled to G proteins? Bioessays 2014; 35:1025-34. [PMID: 24185813 DOI: 10.1002/bies.201300082] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
It was, until recently, accepted that the two classes of acetylcholine (ACh) receptors are distinct in an important sense: muscarinic ACh receptors signal via heterotrimeric GTP binding proteins (G proteins), whereas nicotinic ACh receptors (nAChRs) open to allow flux of Na+, Ca2+, and K+ ions into the cell after activation. Here we present evidence of direct coupling between G proteins and nAChRs in neurons. Based on proteomic, biophysical, and functional evidence, we hypothesize that binding to G proteins modulates the activity and signaling of nAChRs in cells. It is important to note that while this hypothesis is new for the nAChR, it is consistent with known interactions between G proteins and structurally related ligand-gated ion channels. Therefore, it underscores an evolutionarily conserved metabotropic mechanism of G protein signaling via nAChR channels.
Collapse
|
48
|
Scimia MC, Cannavo A, Koch WJ. Gene therapy for heart disease: molecular targets, vectors and modes of delivery to myocardium. Expert Rev Cardiovasc Ther 2014; 11:999-1013. [PMID: 23984926 DOI: 10.1586/14779072.2013.818813] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Despite the numerous hurdles that gene therapy has encountered along the way, clinical trials over the last few years are showing promising results in many fields of medicine, including cardiology, where many targets are moving toward clinical development. In this review, the authors discuss the current state of the art in terms of clinical and preclinical development. They also examine vector technology and available vector-delivery strategies.
Collapse
Affiliation(s)
- Maria Cecilia Scimia
- Department of Pharmacology, Center for Translational Medicine, Temple University School of Medicine, 3500 N Broad St, MERB 941, Philadelphia, PA 19140, USA
| | | | | |
Collapse
|
49
|
Liu S, Premont RT, Rockey DC. Endothelial nitric-oxide synthase (eNOS) is activated through G-protein-coupled receptor kinase-interacting protein 1 (GIT1) tyrosine phosphorylation and Src protein. J Biol Chem 2014; 289:18163-74. [PMID: 24764294 DOI: 10.1074/jbc.m113.521203] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Nitric oxide (NO) is a critical regulator of vascular tone and plays an especially prominent role in liver by controlling portal blood flow and pressure within liver sinusoids. Synthesis of NO in sinusoidal endothelial cells by endothelial nitric-oxide synthase (eNOS) is regulated in response to activation of endothelial cells by vasoactive signals such as endothelins. The endothelin B (ETB) receptor is a G-protein-coupled receptor, but the mechanisms by which it regulates eNOS activity in sinusoidal endothelial cells are not well understood. In this study, we built on two previous strands of work, the first showing that G-protein βγ subunits mediated activation of phosphatidylinositol 3-kinase and Akt to regulate eNOS and the second showing that eNOS directly bound to the G-protein-coupled receptor kinase-interacting protein 1 (GIT1) scaffold protein, and this association stimulated NO production. Here we investigated the mechanisms by which the GIT1-eNOS complex is formed and regulated. GIT1 was phosphorylated on tyrosine by Src, and Y293F and Y554F mutations reduced GIT1 phosphorylation as well as the ability of GIT1 to bind to and activate eNOS. Akt phosphorylation activated eNOS (at Ser(1177)), and Akt also regulated the ability of Src to phosphorylate GIT1 as well as GIT1-eNOS association. These pathways were activated by endothelin-1 through the ETB receptor; inhibiting receptor-activated G-protein βγ subunits blocked activation of Akt, GIT1 tyrosine phosphorylation, and ET-1-stimulated GIT1-eNOS association but did not affect Src activation. These data suggest a model in which Src and Akt cooperate to regulate association of eNOS with the GIT1 scaffold to facilitate NO production.
Collapse
Affiliation(s)
- Songling Liu
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Richard T Premont
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710
| | - Don C Rockey
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| |
Collapse
|
50
|
Abstract
INTRODUCTION Cardiovascular gene therapy is the third most popular application for gene therapy, representing 8.4% of all gene therapy trials as reported in 2012 estimates. Gene therapy in cardiovascular disease is aiming to treat heart failure from ischemic and non-ischemic causes, peripheral artery disease, venous ulcer, pulmonary hypertension, atherosclerosis and monogenic diseases, such as Fabry disease. AREAS COVERED In this review, we will focus on elucidating current molecular targets for the treatment of ventricular dysfunction following myocardial infarction (MI). In particular, we will focus on the treatment of i) the clinical consequences of it, such as heart failure and residual myocardial ischemia and ii) etiological causes of MI (coronary vessels atherosclerosis, bypass venous graft disease, in-stent restenosis). EXPERT OPINION We summarise the scheme of the review and the molecular targets either already at the gene therapy clinical trial phase or in the pipeline. These targets will be discussed below. Following this, we will focus on what we believe are the 4 prerequisites of success of any gene target therapy: safety, expression, specificity and efficacy (SESE).
Collapse
Affiliation(s)
- Maria C Scimia
- Temple University, Translational Medicine/Pharmacology , 3500 N. Broad Street, Philadelphia, 19140 , USA
| | | | | |
Collapse
|