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Nogueras-Ortiz C, Roman-Vendrell C, Mateo-Semidey GE, Liao YH, Kendall DA, Yudowski GA. Retromer stops beta-arrestin 1-mediated signaling from internalized cannabinoid 2 receptors. Mol Biol Cell 2017; 28:3554-3561. [PMID: 28954865 PMCID: PMC5683765 DOI: 10.1091/mbc.e17-03-0198] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 08/18/2017] [Accepted: 09/20/2017] [Indexed: 12/18/2022] Open
Abstract
The retromer acts as the gatekeeper blocking signaling mediated by beta-arrestin 1 from internalized cannabinoid 2 receptors. This work provides further confirmation of the relevance and prevalence of signaling from internalized receptors at endosomal compartments after ligand-induced endocytosis. G protein–coupled receptors mediate their complex functions through activation of signaling cascades from receptors localized at the cell surface and endosomal compartments. These signaling pathways are modulated by heterotrimeric G proteins and the scaffold proteins beta-arrestin 1 and 2. However, in contrast to the events occurring at the cell surface, our knowledge of the mechanisms controlling signaling from receptors localized at intracellular compartments is still very limited. Here we sought to investigate the intracellular signaling from cannabinoid 2 receptor (CB2R). First, we show that receptor internalization is required for agonist-induced phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). Then we demonstrate that ERK1/2 activation is mediated by beta-arrestin 1 from receptors localized exclusively at Rab4/5 compartments. Finally, we identify the retromer complex as a gatekeeper, terminating beta-arrestin 1–mediated ERK phosphorylation. These findings extend our understanding of the events controlling signaling from endocytosed receptors and identify the retromer as a modulator of beta-arrestin–mediated signaling from CB2R.
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Affiliation(s)
| | - Cristina Roman-Vendrell
- Institute of Neurobiology, University of Puerto Rico, San Juan, PR 00901.,Department of Physiology and Biophysics, University of Puerto Rico, Medical San Juan, PR 00936
| | - Gabriel E Mateo-Semidey
- Institute of Neurobiology, University of Puerto Rico, San Juan, PR 00901.,Department of Anatomy and Neurobiology, University of Puerto Rico, Medical San Juan, PR 00936.,Department of Anatomy and Neurobiology, University of Puerto Rico, Medical San Juan, PR 00936
| | - Yu-Hsien Liao
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-3092
| | - Debra A Kendall
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-3092
| | - Guillermo A Yudowski
- Institute of Neurobiology, University of Puerto Rico, San Juan, PR 00901 .,Department of Anatomy and Neurobiology, University of Puerto Rico, Medical San Juan, PR 00936.,Department of Anatomy and Neurobiology, University of Puerto Rico, Medical San Juan, PR 00936
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102
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Inda C, Armando NG, Dos Santos Claro PA, Silberstein S. Endocrinology and the brain: corticotropin-releasing hormone signaling. Endocr Connect 2017; 6:R99-R120. [PMID: 28710078 PMCID: PMC5551434 DOI: 10.1530/ec-17-0111] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 07/14/2017] [Indexed: 01/01/2023]
Abstract
Corticotropin-releasing hormone (CRH) is a key player of basal and stress-activated responses in the hypothalamic-pituitary-adrenal axis (HPA) and in extrahypothalamic circuits, where it functions as a neuromodulator to orchestrate humoral and behavioral adaptive responses to stress. This review describes molecular components and cellular mechanisms involved in CRH signaling downstream of its G protein-coupled receptors (GPCRs) CRHR1 and CRHR2 and summarizes recent findings that challenge the classical view of GPCR signaling and impact on our understanding of CRHRs function. Special emphasis is placed on recent studies of CRH signaling that revealed new mechanistic aspects of cAMP generation and ERK1/2 activation in physiologically relevant contexts of the neurohormone action. In addition, we present an overview of the pathophysiological role of the CRH system, which highlights the need for a precise definition of CRHRs signaling at molecular level to identify novel targets for pharmacological intervention in neuroendocrine tissues and specific brain areas involved in CRH-related disorders.
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Affiliation(s)
- Carolina Inda
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck SocietyBuenos Aires, Argentina
- DFBMCFacultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Natalia G Armando
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck SocietyBuenos Aires, Argentina
| | - Paula A Dos Santos Claro
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck SocietyBuenos Aires, Argentina
| | - Susana Silberstein
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck SocietyBuenos Aires, Argentina
- DFBMCFacultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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103
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Bahouth SW, Nooh MM. Barcoding of GPCR trafficking and signaling through the various trafficking roadmaps by compartmentalized signaling networks. Cell Signal 2017; 36:42-55. [PMID: 28449947 PMCID: PMC5512170 DOI: 10.1016/j.cellsig.2017.04.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/21/2017] [Accepted: 04/22/2017] [Indexed: 01/08/2023]
Abstract
Proper signaling by G protein coupled receptors (GPCR) is dependent on the specific repertoire of transducing, enzymatic and regulatory kinases and phosphatases that shape its signaling output. Activation and signaling of the GPCR through its cognate G protein is impacted by G protein-coupled receptor kinase (GRK)-imprinted "barcodes" that recruit β-arrestins to regulate subsequent desensitization, biased signaling and endocytosis of the GPCR. The outcome of agonist-internalized GPCR in endosomes is also regulated by sequence motifs or "barcodes" within the GPCR that mediate its recycling to the plasma membrane or retention and eventual degradation as well as its subsequent signaling in endosomes. Given the vast number of diverse sequences in GPCR, several trafficking mechanisms for endosomal GPCR have been described. The majority of recycling GPCR, are sorted out of endosomes in a "sequence-dependent pathway" anchored around a type-1 PDZ-binding module found in their C-tails. For a subset of these GPCR, a second "barcode" imprinted onto specific GPCR serine/threonine residues by compartmentalized kinase networks was required for their efficient recycling through the "sequence-dependent pathway". Mutating the serine/threonine residues involved, produced dramatic effects on GPCR trafficking, indicating that they played a major role in setting the trafficking itinerary of these GPCR. While endosomal SNX27, retromer/WASH complexes and actin were required for efficient sorting and budding of all these GPCR, additional proteins were required for GPCR sorting via the second "barcode". Here we will review recent developments in GPCR trafficking in general and the human β1-adrenergic receptor in particular across the various trafficking roadmaps. In addition, we will discuss the role of GPCR trafficking in regulating endosomal GPCR signaling, which promote biochemical and physiological effects that are distinct from those generated by the GPCR signal transduction pathway in membranes.
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Affiliation(s)
- Suleiman W Bahouth
- Department of Pharmacology, The University of Tennessee Health Sciences Center, 71 S. Manassas, Memphis, TN 38103, USA.
| | - Mohammed M Nooh
- Department of Biochemistry, Faculty of Pharmacy Cairo University, Kasr El-Aini St., Cairo 11562, Egypt
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104
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MoEnd3 regulates appressorium formation and virulence through mediating endocytosis in rice blast fungus Magnaporthe oryzae. PLoS Pathog 2017. [PMID: 28628655 PMCID: PMC5491321 DOI: 10.1371/journal.ppat.1006449] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Eukaryotic cells respond to environmental stimuli when cell surface receptors are bound by environmental ligands. The binding initiates a signal transduction cascade that results in the appropriate intracellular responses. Studies have shown that endocytosis is critical for receptor internalization and signaling activation. In the rice blast fungus Magnaporthe oryzae, a non-canonical G-protein coupled receptor, Pth11, and membrane sensors MoMsb2 and MoSho1 are thought to function upstream of G-protein/cAMP signaling and the Pmk1 MAPK pathway to regulate appressorium formation and pathogenesis. However, little is known about how these receptors or sensors are internalized and transported into intracellular compartments. We found that the MoEnd3 protein is important for endocytic transport and that the ΔMoend3 mutant exhibited defects in efficient internalization of Pth11 and MoSho1. The ΔMoend3 mutant was also defective in Pmk1 phosphorylation, autophagy, appressorium formation and function. Intriguingly, restoring Pmk1 phosphorylation levels in ΔMoend3 suppressed most of these defects. Moreover, we demonstrated that MoEnd3 is subject to regulation by MoArk1 through protein phosphorylation. We also found that MoEnd3 has additional functions in facilitating the secretion of effectors, including Avr-Pia and AvrPiz-t that suppress rice immunity. Taken together, our findings suggest that MoEnd3 plays a critical role in mediating receptor endocytosis that is critical for the signal transduction-regulated development and virulence of M. oryzae.
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105
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Inda C, Bonfiglio JJ, Dos Santos Claro PA, Senin SA, Armando NG, Deussing JM, Silberstein S. cAMP-dependent cell differentiation triggered by activated CRHR1 in hippocampal neuronal cells. Sci Rep 2017; 7:1944. [PMID: 28512295 PMCID: PMC5434020 DOI: 10.1038/s41598-017-02021-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/04/2017] [Indexed: 12/18/2022] Open
Abstract
Corticotropin-releasing hormone receptor 1 (CRHR1) activates the atypical soluble adenylyl cyclase (sAC) in addition to transmembrane adenylyl cyclases (tmACs). Both cAMP sources were shown to be required for the phosphorylation of ERK1/2 triggered by activated G protein coupled receptor (GPCR) CRHR1 in neuronal and neuroendocrine contexts. Here, we show that activated CRHR1 promotes growth arrest and neurite elongation in neuronal hippocampal cells (HT22-CRHR1 cells). By characterising CRHR1 signalling mechanisms involved in the neuritogenic effect, we demonstrate that neurite outgrowth in HT22-CRHR1 cells takes place by a sAC-dependent, ERK1/2-independent signalling cascade. Both tmACs and sAC are involved in corticotropin-releasing hormone (CRH)-mediated CREB phosphorylation and c-fos induction, but only sAC-generated cAMP pools are critical for the neuritogenic effect of CRH, further highlighting the engagement of two sources of cAMP downstream of the activation of a GPCR, and reinforcing the notion that restricted cAMP microdomains may regulate independent cellular processes.
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Affiliation(s)
- Carolina Inda
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina.,DFBMC, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Juan José Bonfiglio
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina.,Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Paula A Dos Santos Claro
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina.,DFBMC, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sergio A Senin
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Natalia G Armando
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Jan M Deussing
- Max Planck Institute of Psychiatry, Department of Stress Neurobiology and Neurogenetics, Molecular Neurogenetics, Munich, Germany
| | - Susana Silberstein
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina. .,DFBMC, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
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106
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
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Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
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107
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A new inhibitor of the β-arrestin/AP2 endocytic complex reveals interplay between GPCR internalization and signalling. Nat Commun 2017; 8:15054. [PMID: 28416805 PMCID: PMC5399295 DOI: 10.1038/ncomms15054] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 02/23/2017] [Indexed: 02/08/2023] Open
Abstract
In addition to G protein-coupled receptor (GPCR) desensitization and endocytosis, β-arrestin recruitment to ligand-stimulated GPCRs promotes non-canonical signalling cascades. Distinguishing the respective contributions of β-arrestin recruitment to the receptor and β-arrestin-promoted endocytosis in propagating receptor signalling has been limited by the lack of selective analytical tools. Here, using a combination of virtual screening and cell-based assays, we have identified a small molecule that selectively inhibits the interaction between β-arrestin and the β2-adaptin subunit of the clathrin adaptor protein AP2 without interfering with the formation of receptor/β-arrestin complexes. This selective β-arrestin/β2-adaptin inhibitor (Barbadin) blocks agonist-promoted endocytosis of the prototypical β2-adrenergic (β2AR), V2-vasopressin (V2R) and angiotensin-II type-1 (AT1R) receptors, but does not affect β-arrestin-independent (transferrin) or AP2-independent (endothelin-A) receptor internalization. Interestingly, Barbadin fully blocks V2R-stimulated ERK1/2 activation and blunts cAMP accumulation promoted by both V2R and β2AR, supporting the concept of β-arrestin/AP2-dependent signalling for both G protein-dependent and -independent pathways. Beta-arrestins play central roles in the mechanisms regulating GPCR signalling and trafficking. Here the authors identify a selective inhibitor of the interaction between β-arrestin and the β2-adaptin subunit of the clathrin adaptor protein AP-2, which they use to dissect the role of the β-arrestin/β2-adaptin interaction in GPCR signalling.
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108
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Carroll SH, Zhang E, Wang BF, LeClair KB, Rahman A, Cohen DE, Plutzky J, Patwari P, Lee RT. Adipocyte arrestin domain-containing 3 protein (Arrdc3) regulates uncoupling protein 1 (Ucp1) expression in white adipose independently of canonical changes in β-adrenergic receptor signaling. PLoS One 2017; 12:e0173823. [PMID: 28291835 PMCID: PMC5349670 DOI: 10.1371/journal.pone.0173823] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 02/26/2017] [Indexed: 11/19/2022] Open
Abstract
Adaptive thermogenesis and cold-induced activation of uncoupling protein 1 (Ucp1) in brown adipose tissue in rodents is well-described and attributed to sympathetic activation of β-adrenergic signaling. The arrestin domain containing protein Arrdc3 is a regulator of obesity in mice and also appears linked to obesity in humans. We generated a mouse with conditional deletion of Arrdc3, and here we present evidence that genetic ablation of Arrdc3 specifically in adipocytes results in increased Ucp1 expression in subcutaneous and parametrial adipose tissue. Although this increase in expression did not correspond with significant changes in body weight or energy expenditure, adipocyte-specific Arrdc3-null mice had improved glucose tolerance. It was previously hypothesized that Arrdc3 ablation leads to increased β-adrenergic receptor sensitivity; however, in vitro experiments show that Arrdc3-null adipocytes responded to β-adrenergic receptor agonist with decreased Ucp1 levels. Additionally, canonical β-adrenergic receptor signaling was not different in Arrdc3-null adipocytes. These data reveal a role for Arrdc3 in the regulation of Ucp1 expression in adipocytes. However, this adipocyte effect is insufficient to generate the obesity-resistant phenotype of mice with ubiquitous deletion of Arrdc3, indicating a likely role for Arrdc3 in cells other than adipocytes.
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Affiliation(s)
- Shannon H. Carroll
- Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Ellen Zhang
- Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Bing F. Wang
- Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Katherine B. LeClair
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Arifeen Rahman
- Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - David E. Cohen
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jorge Plutzky
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Parth Patwari
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Richard T. Lee
- Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
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109
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Ghosh P, Rangamani P, Kufareva I. The GAPs, GEFs, GDIs and…now, GEMs: New kids on the heterotrimeric G protein signaling block. Cell Cycle 2017; 16:607-612. [PMID: 28287365 DOI: 10.1080/15384101.2017.1282584] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The canonical process of activation of heterotrimeric G proteins by G protein coupled receptors (GPCRs) is well studied. Recently, a rapidly emerging paradigm has revealed the existence of a new, non-canonical set of cytosolic G protein modulators, guanine exchange modulators (GEMs). Among G proteins regulators, GEMs are uniquely capable of initiating pleiotropic signals: these bifunctional modulators can activate cAMP inhibitory (Gi) proteins and inhibit cAMP-stimulatory (Gs) proteins through a single short evolutionarily conserved module. A prototypical member of the GEM family, GIV/Girdin, integrates signals downstream of a myriad of cell surface receptors, e.g., growth factor RTKs, integrins, cytokine, GPCRs, etc., and translates these signals into G protein activation or inhibition. By their pleiotropic action, GIV and other GEMs modulate several key pathways within downstream signaling network. Unlike canonical G protein signaling that is finite and is triggered directly and exclusively by GPCRs, the temporal and spatial features of non-canonical activation of G protein via GIV-family of cytosolic GEMs are unusually relaxed. GIV uses this relaxed circuitry to integrate, reinforce and compartmentalize signals downstream of both growth factors and G proteins in a way that enables it to orchestrate cellular phenotypes in a sustained manner. Mounting evidence suggests the importance of GIV and other GEMs as disease modulators and their potential to serve as therapeutic targets; however, a lot remains unknown within the layers of the proverbial onion that must be systematically peeled. This perspective summarizes the key concepts of the GEM-dependent G protein signaling paradigm and discusses the multidisciplinary approaches that are likely to revolutionize our understanding of this paradigm from the atomic level to systems biology.
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Affiliation(s)
- Pradipta Ghosh
- a Departments of Medicine and Cell and Molecular Medicine , University of California at San Diego , La Jolla , CA , USA
| | - Padmini Rangamani
- b Department of Mechanical and Aerospace Engineering , Jacobs School of Engineering, University of California at San Diego , La Jolla , CA , USA
| | - Irina Kufareva
- c Skaggs School of Pharmacy and Pharmaceutical Sciences , University of California at San Diego , La Jolla , CA , USA
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110
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Pavlos NJ, Friedman PA. GPCR Signaling and Trafficking: The Long and Short of It. Trends Endocrinol Metab 2017; 28:213-226. [PMID: 27889227 PMCID: PMC5326587 DOI: 10.1016/j.tem.2016.10.007] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 10/17/2016] [Accepted: 10/26/2016] [Indexed: 01/24/2023]
Abstract
Emerging findings disclose unexpected components of G protein-coupled receptor (GPCR) signaling and cell biology. Select GPCRs exhibit classical signaling, that is restricted to cell membranes, as well as newly described persistent signaling that depends on internalization of the GPCR bound to β-arrestins. Termination of non-canonical endosomal signaling requires intraluminal acidification and sophisticated protein trafficking machineries. Recent studies reveal the structural determinants of the trafficking chaperones. This review summarizes advances in GPCR signaling and trafficking with a focus on the parathyroid hormone receptor (PTHR) as a prototype, and on the actin-sorting nexin 27 (SNX27)-retromer tubule (ASRT) complex, an endosomal sorting hub responsible for recycling and preservation of cell surface receptors. The findings are integrated into a model of PTHR trafficking with implications for signal transduction, bone growth, and mineral ion metabolism.
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Affiliation(s)
- Nathan J Pavlos
- Cellular Orthopaedic Laboratory, School of Surgery, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Peter A Friedman
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, Department of Structural Biology University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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111
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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.
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Affiliation(s)
| | - Sudha K Shenoy
- Department of Medicine (Cardiology), Durham, NC, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.
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112
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Sergin I, Jong YJI, Harmon SK, Kumar V, O'Malley KL. Sequences within the C Terminus of the Metabotropic Glutamate Receptor 5 (mGluR5) Are Responsible for Inner Nuclear Membrane Localization. J Biol Chem 2017; 292:3637-3655. [PMID: 28096465 DOI: 10.1074/jbc.m116.757724] [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] [Received: 09/08/2016] [Revised: 01/12/2017] [Indexed: 12/19/2022] Open
Abstract
Traditionally, G-protein-coupled receptors (GPCR) are thought to be located on the cell surface where they transmit extracellular signals to the cytoplasm. However, recent studies indicate that some GPCRs are also localized to various subcellular compartments such as the nucleus where they appear required for various biological functions. For example, the metabotropic glutamate receptor 5 (mGluR5) is concentrated at the inner nuclear membrane (INM) where it mediates Ca2+ changes in the nucleoplasm by coupling with Gq/11 Here, we identified a region within the C-terminal domain (amino acids 852-876) that is necessary and sufficient for INM localization of the receptor. Because these sequences do not correspond to known nuclear localization signal motifs, they represent a new motif for INM trafficking. mGluR5 is also trafficked to the plasma membrane where it undergoes re-cycling/degradation in a separate receptor pool, one that does not interact with the nuclear mGluR5 pool. Finally, our data suggest that once at the INM, mGluR5 is stably retained via interactions with chromatin. Thus, mGluR5 is perfectly positioned to regulate nucleoplasmic Ca2+in situ.
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Affiliation(s)
- Ismail Sergin
- From the Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Yuh-Jiin I Jong
- From the Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Steven K Harmon
- From the Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Vikas Kumar
- From the Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Karen L O'Malley
- From the Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110
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113
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Kendall DA, Yudowski GA. Cannabinoid Receptors in the Central Nervous System: Their Signaling and Roles in Disease. Front Cell Neurosci 2017; 10:294. [PMID: 28101004 PMCID: PMC5209363 DOI: 10.3389/fncel.2016.00294] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 12/08/2016] [Indexed: 11/15/2022] Open
Abstract
The identification and cloning of the two major cannabinoid (CB1 and CB2) receptors together with the discovery of their endogenous ligands in the late 80s and early 90s, resulted in a major effort aimed at understanding the mechanisms and physiological roles of the endocannabinoid system (ECS). Due to its expression and localization in the central nervous system (CNS), the CB1 receptor together with its endogenous ligands (endocannabinoids (eCB)) and the enzymes involved in their synthesis and degradation, has been implicated in multiple pathophysiological events ranging from memory deficits to neurodegenerative disorders among others. In this review, we will provide a general overview of the ECS with emphasis on the CB1 receptor in health and disease. We will describe our current understanding of the complex aspects of receptor signaling and trafficking, including the non-canonical signaling pathways such as those mediated by β-arrestins within the context of functional selectivity and ligand bias. Finally, we will highlight some of the disorders in which CB1 receptors have been implicated. Significant knowledge has been achieved over the last 30 years. However, much more research is still needed to fully understand the complex roles of the ECS, particularly in vivo and to unlock its true potential as a source of therapeutic targets.
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Affiliation(s)
- Debra A Kendall
- Department of Pharmaceutical Sciences, University of Connecticut Storrs, CT, USA
| | - Guillermo A Yudowski
- Department of Anatomy and Neurobiology, University of Puerto Rico, Medical Sciences CampusSan Juan, Puerto Rico; Institute of Neurobiology, University of Puerto RicoSan Juan, Puerto Rico
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114
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Tang W, Huang B, Wang J, An L, Zhong H, Yang H, Li P, Chen J. A label-free screening approach targeted protease-activated receptor 1 based on dynamic mass redistribution in living cells. RSC Adv 2017. [DOI: 10.1039/c7ra07927c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Protease-activated receptor 1 (PAR-1) antagonists strongly inhibit thrombin-induced platelet aggregation and are proved to be effective as anti-thrombotic drugs.
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Affiliation(s)
- Weiwei Tang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Bixia Huang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Jiancheng Wang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Lin An
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | | | - Hua Yang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Ping Li
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Jun Chen
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
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115
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Subcellular Targeting of PDE4 in Cardiac Myocytes and Generation of Signaling Compartments. MICRODOMAINS IN THE CARDIOVASCULAR SYSTEM 2017. [DOI: 10.1007/978-3-319-54579-0_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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116
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Foster SR, Bräuner-Osborne H. Investigating Internalization and Intracellular Trafficking of GPCRs: New Techniques and Real-Time Experimental Approaches. Handb Exp Pharmacol 2017; 245:41-61. [PMID: 29018878 DOI: 10.1007/164_2017_57] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The ability to regulate the interaction between cells and their extracellular environment is essential for the maintenance of appropriate physiological function. For G protein-coupled receptors (GPCRs), this regulation occurs through multiple mechanisms that provide spatial and temporal control for signal transduction. One of the major mechanisms for GPCR regulation involves their endocytic trafficking, which serves to internalize the receptors from the plasma membrane and thereby attenuate G protein-dependent signaling. However, there is accumulating evidence to suggest that GPCRs can signal independently of G proteins, as well as from intracellular compartments including endosomes. It is in this context that receptor internalization and intracellular trafficking have attracted renewed interest within the GPCR field. In this chapter, we will review the current understanding and methodologies that have been used to investigate internalization and intracellular signaling of GPCRs, with a particular focus on emerging real-time techniques. These recent developments have improved our understanding of the complexities of GPCR internalization and intracellular signaling and suggest that the broader biological relevance and potential therapeutic implications of these processes remain to be explored.
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Affiliation(s)
- Simon R Foster
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - Hans Bräuner-Osborne
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
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117
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Webling K, Runesson J, Lang A, Saar I, Kofler B, Langel Ü. Ala 5-galanin (2-11) is a GAL 2R specific galanin analogue. Neuropeptides 2016; 60:75-82. [PMID: 27592409 DOI: 10.1016/j.npep.2016.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 08/11/2016] [Accepted: 08/22/2016] [Indexed: 12/18/2022]
Abstract
It is over 30years since the regulatory peptide galanin was discovered by Professor Mutt and co-workers. Galanin exerts its effects by binding to three galanin G-protein coupled receptors, namely GAL1R, GAL2R and GAL3R. Each galanin receptor has a different distribution in the central nervous system and the peripheral nervous system as well as distinctive signaling pathways, which implicates that the receptors are involved in different biological- and pathological effects. The delineation of the galaninergic system is however difficult due to a lack of stable, specific galanin receptor ligands. Herein, a new short GAL2R specific ligand, Ala5-galanin (2-11), is presented. The galanin (2-11) modified analogue Ala5-galanin (2-11) was tested in 125I-galanin competitive binding studies for the three galanin receptors and the G-protein coupled receptor signaling properties was tested by the ability to influence second-messenger molecules like inositol phosphate and cyclic adenosine monophosphate. In addition, two different label-free real-time assays, namely EnSpire® based on an optical biosensor and xCELLigence® based on an electric biosensor, were used for evaluating the signaling properties using cell lines with different levels of receptor expression. Ala5-galanin (2-11) was subsequently found to be a full agonist for GAL2R with more than 375-fold preference for GAL2R compared to both GAL1R and GAL3R. The single amino acid substitution of serine to alanine at position 5 in the short ligand galanin (2-11) resulted in a ligand subsequently unable to bind neither GAL3R nor GAL1R, even at concentrations as high as 0.1mM.
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Affiliation(s)
- Kristin Webling
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden.
| | - Johan Runesson
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden
| | - Andreas Lang
- Research Program for Receptorbiochemistry and Tumormetabolism, Laura Bassi Centre of Expertise THERAPEP, Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Müllner Hauptstr. 48, A-5020 Salzburg, Austria
| | - Indrek Saar
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Barbara Kofler
- Research Program for Receptorbiochemistry and Tumormetabolism, Laura Bassi Centre of Expertise THERAPEP, Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Müllner Hauptstr. 48, A-5020 Salzburg, Austria
| | - Ülo Langel
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden; Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
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118
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Uchida Y, Rutaganira FU, Jullié D, Shokat KM, von Zastrow M. Endosomal Phosphatidylinositol 3-Kinase Is Essential for Canonical GPCR Signaling. Mol Pharmacol 2016; 91:65-73. [PMID: 27821547 DOI: 10.1124/mol.116.106252] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/04/2016] [Indexed: 02/04/2023] Open
Abstract
G protein-coupled receptors (GPCRs), the largest family of signaling receptors, are critically regulated by endosomal trafficking, suggesting that endosomes might provide new strategies for manipulating GPCR signaling. Here we test this hypothesis by focusing on class III phosphatidylinositol 3-kinase (Vps34), which is an essential regulator of endosomal trafficking. We verify that Vps34 is required for recycling of the β2-adrenoceptor (β2AR), a prototypical GPCR, and then investigate the effects of Vps34 inhibition on the canonical cAMP response elicited by β2AR activation. Vps34 inhibition impairs the ability of cells to recover this response after prolonged activation, which is in accord with the established role of recycling in GPCR resensitization. In addition, Vps34 inhibition also attenuates the short-term cAMP response, and its effect begins several minutes after initial agonist application. These results establish Vps34 as an essential determinant of both short-term and long-term canonical GPCR signaling, and support the potential utility of the endosomal system as a druggable target for signaling.
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Affiliation(s)
- Yasunori Uchida
- Department of Psychiatry (Y.U., D.J., and M.Z.), Department of Cellular and Molecular Pharmacology (F.U.R., K.M.S., and M.Z.), and Howard Hughes Medical Institute (F.U.R. and K.M.S.), University of California, San Francisco, San Francisco, California
| | - Florentine U Rutaganira
- Department of Psychiatry (Y.U., D.J., and M.Z.), Department of Cellular and Molecular Pharmacology (F.U.R., K.M.S., and M.Z.), and Howard Hughes Medical Institute (F.U.R. and K.M.S.), University of California, San Francisco, San Francisco, California
| | - Damien Jullié
- Department of Psychiatry (Y.U., D.J., and M.Z.), Department of Cellular and Molecular Pharmacology (F.U.R., K.M.S., and M.Z.), and Howard Hughes Medical Institute (F.U.R. and K.M.S.), University of California, San Francisco, San Francisco, California
| | - Kevan M Shokat
- Department of Psychiatry (Y.U., D.J., and M.Z.), Department of Cellular and Molecular Pharmacology (F.U.R., K.M.S., and M.Z.), and Howard Hughes Medical Institute (F.U.R. and K.M.S.), University of California, San Francisco, San Francisco, California
| | - Mark von Zastrow
- Department of Psychiatry (Y.U., D.J., and M.Z.), Department of Cellular and Molecular Pharmacology (F.U.R., K.M.S., and M.Z.), and Howard Hughes Medical Institute (F.U.R. and K.M.S.), University of California, San Francisco, San Francisco, California
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119
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Cahill CM, Walwyn W, Taylor AMW, Pradhan AAA, Evans CJ. Allostatic Mechanisms of Opioid Tolerance Beyond Desensitization and Downregulation. Trends Pharmacol Sci 2016; 37:963-976. [PMID: 27670390 DOI: 10.1016/j.tips.2016.08.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 08/18/2016] [Accepted: 08/19/2016] [Indexed: 12/20/2022]
Abstract
Mechanisms of opioid tolerance have focused on adaptive modifications within cells containing opioid receptors, defined here as cellular allostasis, emphasizing regulation of the opioid receptor signalosome. We review additional regulatory and opponent processes involved in behavioral tolerance, and include mechanistic differences both between agonists (agonist bias), and between μ- and δ-opioid receptors. In a process we will refer to as pass-forward allostasis, cells modified directly by opioid drugs impute allostatic changes to downstream circuitry. Because of the broad distribution of opioid systems, every brain cell may be touched by pass-forward allostasis in the opioid-dependent/tolerant state. We will implicate neurons and microglia as interactive contributors to the cumulative allostatic processes creating analgesic and hedonic tolerance to opioid drugs.
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Affiliation(s)
- Catherine M Cahill
- Department of Anesthesiology and Perioperative Care, University of California, Irvine, 837 Health Sciences Road, Irvine, CA 92697, USA
| | - Wendy Walwyn
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | - Anna M W Taylor
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | - Amynah A A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, 1601 West Taylor Street, Chicago, IL 60612, USA
| | - Christopher J Evans
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
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120
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Brailoiu GC, Brailoiu E. Modulation of Calcium Entry by the Endo-lysosomal System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:423-47. [PMID: 27161239 DOI: 10.1007/978-3-319-26974-0_18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Endo-lysosomes are acidic organelles that besides the role in macromolecules degradation, act as intracellular Ca(2+) stores. Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca(2+)-mobilizing second messenger, produced in response to agonist stimulation, activates Ca(2+)-releasing channels on endo-lysosomes and modulates a variety of cellular functions. NAADP-evoked signals are amplified by Ca(2+) release from endoplasmic reticulum, via the recruitment of inositol 1,4,5-trisphosphate and/or ryanodine receptors through a Ca(2+)-induced Ca(2+)- release (CICR) mechanism. The endo-lysosomal Ca(2+) channels activated by NAADP were recently identified as the two-pore channels (TPCs). In addition to TPCs, endo-lysosomes express another distinct family of Ca(2+)- permeable channels, namely the transient receptor potential mucolipin (TRPML) channels, functionally distinct from TPCs. TPCs belong to the voltage-gated channels, resembling voltage-gated Na(+) and Ca(2+) channels. TPCs have important roles in vesicular fusion and trafficking, in triggering a global Ca(2+) signal and in modulation of the membrane excitability. Depletion of acidic Ca(2+) stores has been shown to activate store-operated Ca(2+) entry in human platelets and mouse pancreatic β-cells. In human platelets, Ca(2+) influx in response to acidic stores depletion is facilitated by the tubulin-cytoskeleton and occurs through non-selective cation channels and transient receptor potential canonical (TRPC) channels. Emerging evidence indicates that activation of intracellular receptors, situated on endo-lysosomes, elicits canonical and non-canonical signaling mechanisms that involve CICR and activation of non-selective cation channels in plasma membrane. The ability of endo-lysosomal Ca(2+) stores to modulate the Ca(2+) release from other organelles and the Ca(2+) entry increases the diversity and complexity of cellular signaling mechanisms.
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Affiliation(s)
- G Cristina Brailoiu
- Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University, 901 Walnut St, Rm 916, Philadelphia, PA, 19107, USA.
| | - Eugen Brailoiu
- Center for Substance Abuse Research, Temple University School of Medicine, 3500 N. Broad Street, Room 848, Philadelphia, PA, 19140, USA
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121
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Lemmon MA, Freed DM, Schlessinger J, Kiyatkin A. The Dark Side of Cell Signaling: Positive Roles for Negative Regulators. Cell 2016; 164:1172-1184. [PMID: 26967284 DOI: 10.1016/j.cell.2016.02.047] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 12/12/2022]
Abstract
Cell signaling is dominated by analyzing positive responses to stimuli. Signal activation is balanced by negative regulators that are generally considered to terminate signaling. Rather than exerting only negative effects, however, many such regulators play important roles in enhancing cell-signaling control. Considering responses downstream of selected cell-surface receptors, we discuss how receptor internalization affects signaling specificity and how rapid kinase/phosphatase and GTP/GDP cycles increase responsiveness and allow kinetic proofreading in receptor signaling. We highlight the blurring of distinctions between positive and negative signals, recasting signal termination as the response to a switch-like transition into a new cellular state.
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Affiliation(s)
- Mark A Lemmon
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA.
| | - Daniel M Freed
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
| | - Joseph Schlessinger
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
| | - Anatoly Kiyatkin
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, West Haven, CT 06516, USA
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122
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Hanson J, Chevigné A. GPCRs in immunity: Atypical receptors and novel concepts. Biochem Pharmacol 2016; 114:1-2. [DOI: 10.1016/j.bcp.2016.06.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 06/27/2016] [Indexed: 12/22/2022]
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123
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Inda C, Dos Santos Claro PA, Bonfiglio JJ, Senin SA, Maccarrone G, Turck CW, Silberstein S. Different cAMP sources are critically involved in G protein-coupled receptor CRHR1 signaling. J Cell Biol 2016; 214:181-95. [PMID: 27402953 PMCID: PMC4949449 DOI: 10.1083/jcb.201512075] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 06/10/2016] [Indexed: 02/07/2023] Open
Abstract
Corticotropin-releasing hormone receptor 1 (CRHR1) activates G protein-dependent and internalization-dependent signaling mechanisms. Here, we report that the cyclic AMP (cAMP) response of CRHR1 in physiologically relevant scenarios engages separate cAMP sources, involving the atypical soluble adenylyl cyclase (sAC) in addition to transmembrane adenylyl cyclases (tmACs). cAMP produced by tmACs and sAC is required for the acute phase of extracellular signal regulated kinase 1/2 activation triggered by CRH-stimulated CRHR1, but only sAC activity is essential for the sustained internalization-dependent phase. Thus, different cAMP sources are involved in different signaling mechanisms. Examination of the cAMP response revealed that CRH-activated CRHR1 generates cAMP after endocytosis. Characterizing CRHR1 signaling uncovered a specific link between CRH-activated CRHR1, sAC, and endosome-based signaling. We provide evidence of sAC being involved in an endocytosis-dependent cAMP response, strengthening the emerging model of GPCR signaling in which the cAMP response does not occur exclusively at the plasma membrane and introducing the notion of sAC as an alternative source of cAMP.
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Affiliation(s)
- Carolina Inda
- Instituto de Investigación en Biomedicina de Buenos Aires-CONICET-Partner Institute of the Max Planck Society, C1425FQD Buenos Aires, Argentina Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina
| | - Paula A Dos Santos Claro
- Instituto de Investigación en Biomedicina de Buenos Aires-CONICET-Partner Institute of the Max Planck Society, C1425FQD Buenos Aires, Argentina Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina
| | - Juan J Bonfiglio
- Instituto de Investigación en Biomedicina de Buenos Aires-CONICET-Partner Institute of the Max Planck Society, C1425FQD Buenos Aires, Argentina Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina
| | - Sergio A Senin
- Instituto de Investigación en Biomedicina de Buenos Aires-CONICET-Partner Institute of the Max Planck Society, C1425FQD Buenos Aires, Argentina
| | - Giuseppina Maccarrone
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804 Munich, Germany
| | - Christoph W Turck
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804 Munich, Germany
| | - Susana Silberstein
- Instituto de Investigación en Biomedicina de Buenos Aires-CONICET-Partner Institute of the Max Planck Society, C1425FQD Buenos Aires, Argentina Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina
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124
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Caldieri G, Sigismund S. Spatial resolution of cAMP signaling by soluble adenylyl cyclase. J Cell Biol 2016; 214:125-7. [PMID: 27402955 PMCID: PMC4949454 DOI: 10.1083/jcb.201606123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 06/28/2016] [Indexed: 02/06/2023] Open
Abstract
G protein–coupled receptor signaling starts at the plasma membrane and continues at endosomal stations. In this issue, Inda et al. (2016. J. Cell Biol.http://dx.doi.org/10.1083/jcb.201512075) show that different forms of adenylyl cyclase are activated at the plasma membrane versus endosomes, providing a rationale for the spatial encoding of cAMP signaling.
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Affiliation(s)
- Giusi Caldieri
- Fondazione Istituto FIRC di Oncologia Molecolare, 20139 Milan, Italy
| | - Sara Sigismund
- Fondazione Istituto FIRC di Oncologia Molecolare, 20139 Milan, Italy
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125
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Yang J, Villar VAM, Armando I, Jose PA, Zeng C. G Protein-Coupled Receptor Kinases: Crucial Regulators of Blood Pressure. J Am Heart Assoc 2016; 5:JAHA.116.003519. [PMID: 27390269 PMCID: PMC5015388 DOI: 10.1161/jaha.116.003519] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China Department of Cardiology, Chongqing Key Laboratory for Hypertension, Chongqing Institute of Cardiology, Chongqing Cardiovascular Clinical Research Center, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Van Anthony M Villar
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Ines Armando
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Pedro A Jose
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Chunyu Zeng
- Department of Cardiology, Chongqing Key Laboratory for Hypertension, Chongqing Institute of Cardiology, Chongqing Cardiovascular Clinical Research Center, Daping Hospital, The Third Military Medical University, Chongqing, China
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126
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Yoo JH, Shi DS, Grossmann AH, Sorensen LK, Tong Z, Mleynek TM, Rogers A, Zhu W, Richards JR, Winter JM, Zhu J, Dunn C, Bajji A, Shenderovich M, Mueller AL, Woodman SE, Harbour JW, Thomas KR, Odelberg SJ, Ostanin K, Li DY. ARF6 Is an Actionable Node that Orchestrates Oncogenic GNAQ Signaling in Uveal Melanoma. Cancer Cell 2016; 29:889-904. [PMID: 27265506 PMCID: PMC5027844 DOI: 10.1016/j.ccell.2016.04.015] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 10/16/2015] [Accepted: 04/29/2016] [Indexed: 12/12/2022]
Abstract
Activating mutations in Gαq proteins, which form the α subunit of certain heterotrimeric G proteins, drive uveal melanoma oncogenesis by triggering multiple downstream signaling pathways, including PLC/PKC, Rho/Rac, and YAP. Here we show that the small GTPase ARF6 acts as a proximal node of oncogenic Gαq signaling to induce all of these downstream pathways as well as β-catenin signaling. ARF6 activates these diverse pathways through a common mechanism: the trafficking of GNAQ and β-catenin from the plasma membrane to cytoplasmic vesicles and the nucleus, respectively. Blocking ARF6 with a small-molecule inhibitor reduces uveal melanoma cell proliferation and tumorigenesis in a mouse model, confirming the functional relevance of this pathway and suggesting a therapeutic strategy for Gα-mediated diseases.
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Affiliation(s)
- Jae Hyuk Yoo
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Dallas S Shi
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Allie H Grossmann
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA; ARUP Laboratories, University of Utah, Salt Lake City, UT 84112, USA
| | - Lise K Sorensen
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA
| | - ZongZhong Tong
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA; Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu 610072, China
| | - Tara M Mleynek
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA
| | - Aaron Rogers
- Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Weiquan Zhu
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Division of Cardiovascular Medicine, Department of Medicine, University of Utah, Salt Lake City, UT 84112, USA
| | - Jackson R Richards
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Jacob M Winter
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA
| | - Jie Zhu
- Department of Ophthalmology and Shiley Eye Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Christine Dunn
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA
| | - Ashok Bajji
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA; VioGen Biosciences LLC, Salt Lake City, UT 84119, USA
| | - Mark Shenderovich
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA; Mol3D Research LLC, Salt Lake City, UT 84124, USA
| | - Alan L Mueller
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA
| | - Scott E Woodman
- Department of Melanoma Medical Oncology, Department of Systems Biology, University of Texas, MD Anderson Cancer Center, Houston, TX 77054, USA
| | - J William Harbour
- Ocular Oncology Service, Bascom Palmer Eye Institute and Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Kirk R Thomas
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Division of Hematology, Department of Medicine, University of Utah, Salt Lake City, UT 84112, USA
| | - Shannon J Odelberg
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Division of Cardiovascular Medicine, Department of Medicine, University of Utah, Salt Lake City, UT 84112, USA; Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Kirill Ostanin
- Navigen Inc., 383 Colorow Drive, Salt Lake City, UT 84108, USA.
| | - Dean Y Li
- Department of Medicine, Program in Molecular Medicine, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA; Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA; ARUP Laboratories, University of Utah, Salt Lake City, UT 84112, USA; Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu 610072, China; Division of Cardiovascular Medicine, Department of Medicine, University of Utah, Salt Lake City, UT 84112, USA; Department of Cardiology, VA Salt Lake City Health Care System, Salt Lake City, UT 84112, USA.
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127
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Jensen DD, Zhao P, Jimenez-Vargas NN, Lieu T, Gerges M, Yeatman HR, Canals M, Vanner SJ, Poole DP, Bunnett NW. Protein Kinase D and Gβγ Subunits Mediate Agonist-evoked Translocation of Protease-activated Receptor-2 from the Golgi Apparatus to the Plasma Membrane. J Biol Chem 2016; 291:11285-99. [PMID: 27030010 PMCID: PMC4900274 DOI: 10.1074/jbc.m115.710681] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/17/2016] [Indexed: 12/12/2022] Open
Abstract
Agonist-evoked endocytosis of G protein-coupled receptors has been extensively studied. The mechanisms by which agonists stimulate mobilization and plasma membrane translocation of G protein-coupled receptors from intracellular stores are unexplored. Protease-activated receptor-2 (PAR2) traffics to lysosomes, and sustained protease signaling requires mobilization and plasma membrane trafficking of PAR2 from Golgi stores. We evaluated the contribution of protein kinase D (PKD) and Gβγ to this process. In HEK293 and KNRK cells, the PAR2 agonists trypsin and 2-furoyl-LIGRLO-NH2 activated PKD in the Golgi apparatus, where PKD regulates protein trafficking. PAR2 activation induced translocation of Gβγ, a PKD activator, to the Golgi apparatus, determined by bioluminescence resonance energy transfer between Gγ-Venus and giantin-Rluc8. Inhibitors of PKD (CRT0066101) and Gβγ (gallein) prevented PAR2-stimulated activation of PKD. CRT0066101, PKD1 siRNA, and gallein all inhibited recovery of PAR2-evoked Ca(2+) signaling. PAR2 with a photoconvertible Kaede tag was expressed in KNRK cells to examine receptor translocation from the Golgi apparatus to the plasma membrane. Irradiation of the Golgi region (405 nm) induced green-red photo-conversion of PAR2-Kaede. Trypsin depleted PAR2-Kaede from the Golgi apparatus and repleted PAR2-Kaede at the plasma membrane. CRT0066101 inhibited PAR2-Kaede translocation to the plasma membrane. CRT0066101 also inhibited sustained protease signaling to colonocytes and nociceptive neurons that naturally express PAR2 and mediate protease-evoked inflammation and nociception. Our results reveal a major role for PKD and Gβγ in agonist-evoked mobilization of intracellular PAR2 stores that is required for sustained signaling by extracellular proteases.
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Affiliation(s)
- Dane D Jensen
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
| | - Peishen Zhao
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
| | - Nestor N Jimenez-Vargas
- the Gastrointestinal Diseases Research Unit, Division of Gastroenterology, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - TinaMarie Lieu
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
| | - Marina Gerges
- From the Monash Institute of Pharmaceutical Sciences and
| | | | - Meritxell Canals
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
| | - Stephen J Vanner
- the Gastrointestinal Diseases Research Unit, Division of Gastroenterology, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Daniel P Poole
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia, the Departments of Anatomy and Neuroscience and
| | - Nigel W Bunnett
- From the Monash Institute of Pharmaceutical Sciences and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia, Pharmacology and Therapeutics, University of Melbourne, Parkville, Victoria 3010, Australia, and
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128
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Activation of MEK/ERK Signaling by PACAP in Guinea Pig Cardiac Neurons. J Mol Neurosci 2016; 59:309-16. [PMID: 27194157 DOI: 10.1007/s12031-016-0766-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 04/29/2016] [Indexed: 10/21/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) signaling can increase guinea pig cardiac neuron excitability in part through extracellular signal-regulated kinase (ERK) activation. The present study examined the PACAP receptors and signaling cascades that stimulate guinea pig cardiac neuron ERK signaling using confocal microscopy to quantify PACAP-induced neuronal phosphorylated ERK (pERK) immunoreactivity. PACAP and maxadilan, but not vasoactive intestinal polypeptide (VIP), increased cardiac neuron pERK, implicating primary roles for PACAP-selective PAC1 receptor (Adcyap1r1) signaling rather than VPAC receptors (Vipr1 and Vipr2) in the generation of cardiac neuron pERK. The adenylyl cyclase (AC) activator forskolin, but not the protein kinase C (PKC) activator phorbol myristate acetate (PMA), increased pERK. Also, Bim1 did not blunt PACAP activation of pERK. Together, the results suggest PAC1 receptor signal transduction via Gs/adenylyl cyclase (AC)/cAMP rather than Gq/phospholipase C (PLC) generated neuronal pERK. Activator and inhibitor studies suggested that the PACAP-mediated pERK activation was PKA-dependent rather than an exchange protein directly activated by a cAMP (EPAC), PKA-independent mechanism. The PACAP-induced pERK was inhibited by the clathrin inhibitor Pitstop2 to block receptor internalization and endosomal signaling. We propose that the PACAP-mediated MEK/ERK activation in cardiac neurons involves both AC/cAMP/PKA signaling and PAC1 receptor internalization/activation of signaling endosomes.
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129
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Tian X, Irannejad R, Bowman SL, Du Y, Puthenveedu MA, von Zastrow M, Benovic JL. The α-Arrestin ARRDC3 Regulates the Endosomal Residence Time and Intracellular Signaling of the β2-Adrenergic Receptor. J Biol Chem 2016; 291:14510-25. [PMID: 27226565 DOI: 10.1074/jbc.m116.716589] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 01/12/2023] Open
Abstract
Arrestin domain-containing protein 3 (ARRDC3) is a member of the mammalian α-arrestin family, which is predicted to share similar tertiary structure with visual-/β-arrestins and also contains C-terminal PPXY motifs that mediate interaction with E3 ubiquitin ligases. Recently, ARRDC3 has been proposed to play a role in regulating the trafficking of G protein-coupled receptors, although mechanistic insight into this process is lacking. Here, we focused on characterizing the role of ARRDC3 in regulating the trafficking of the β2-adrenergic receptor (β2AR). We find that ARRDC3 primarily localizes to EEA1-positive early endosomes and directly interacts with the β2AR in a ligand-independent manner. Although ARRDC3 has no effect on β2AR endocytosis or degradation, it negatively regulates β2AR entry into SNX27-occupied endosomal tubules. This results in delayed recycling of the receptor and a concomitant increase in β2AR-dependent endosomal signaling. Thus, ARRDC3 functions as a switch to modulate the endosomal residence time and subsequent intracellular signaling of the β2AR.
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Affiliation(s)
- Xufan Tian
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Roshanak Irannejad
- the Department of Psychiatry, University of California at San Francisco, San Francisco, California 94158
| | - Shanna L Bowman
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and
| | - Yang Du
- the Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305
| | - Manojkumar A Puthenveedu
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and
| | - Mark von Zastrow
- the Department of Psychiatry, University of California at San Francisco, San Francisco, California 94158
| | - Jeffrey L Benovic
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107,
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130
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Bacillus bombysepticus α-Toxin Binding to G Protein-Coupled Receptor Kinase 2 Regulates cAMP/PKA Signaling Pathway to Induce Host Death. PLoS Pathog 2016; 12:e1005527. [PMID: 27022742 PMCID: PMC4811588 DOI: 10.1371/journal.ppat.1005527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 03/04/2016] [Indexed: 02/06/2023] Open
Abstract
Bacterial pathogens and their toxins target host receptors, leading to aberrant behavior or host death by changing signaling events through subversion of host intracellular cAMP level. This is an efficient and widespread mechanism of microbial pathogenesis. Previous studies describe toxins that increase cAMP in host cells, resulting in death through G protein-coupled receptor (GPCR) signaling pathways by influencing adenylyl cyclase or G protein activity. G protein-coupled receptor kinase 2 (GRK2) has a central role in regulation of GPCR desensitization. However, little information is available about the pathogenic mechanisms of toxins associated with GRK2. Here, we reported a new bacterial toxin-Bacillus bombysepticus (Bb) α-toxin that was lethal to host. We showed that Bb α-toxin interacted with BmGRK2. The data demonstrated that Bb α-toxin directly bound to BmGRK2 to promote death by affecting GPCR signaling pathways. This mechanism involved stimulation of Gαs, increase level of cAMP and activation of protein kinase A (PKA). Activated cAMP/PKA signal transduction altered downstream effectors that affected homeostasis and fundamental biological processes, disturbing the structural and functional integrity of cells, resulting in death. Preventing cAMP/PKA signaling transduction by inhibitions (NF449 or H-89) substantially reduced the pathogenicity of Bb α-toxin. The discovery of a toxin-induced host death specifically linked to GRK2 mediated signaling pathway suggested a new model for bacterial toxin action. Characterization of host genes whose expression and function are regulated by Bb α-toxin and GRK2 will offer a deeper understanding of the pathogenesis of infectious diseases caused by pathogens that elevate cAMP. Interference with regulation of host signaling by pathogens can alter gene expression, leading to functional disarray in the host cells that causes abnormal division or death. Here, we propose a previously undescribed model for how bacterial toxins subvert host processes via interaction with GRK2 that influences cAMP/PKA signaling. Our findings provide new fundamental information about how bacterial pathogens regulate host signal transduction to cause death, which offers additional perspectives in host-pathogen systems. These findings will help to advance our understanding of bacteria pathogenic mechanism. Furthermore, these might extend to other microbial pathogenesis and assist in designing new or safer strategies against pathogens.
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131
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Delgado-Peraza F, Ahn KH, Nogueras-Ortiz C, Mungrue IN, Mackie K, Kendall DA, Yudowski GA. Mechanisms of Biased β-Arrestin-Mediated Signaling Downstream from the Cannabinoid 1 Receptor. Mol Pharmacol 2016; 89:618-29. [PMID: 27009233 PMCID: PMC4885504 DOI: 10.1124/mol.115.103176] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 03/22/2016] [Indexed: 12/23/2022] Open
Abstract
Activation of G protein-coupled receptors results in multiple waves of signaling that are mediated by heterotrimeric G proteins and the scaffolding proteins β-arrestin 1/2. Ligands can elicit full or subsets of cellular responses, a concept defined as ligand bias or functional selectivity. However, our current understanding of β-arrestin-mediated signaling is still very limited. Here we provide a comprehensive view of β-arrestin-mediated signaling from the cannabinoid 1 receptor (CB1R). By using a signaling biased receptor, we define the cascades, specific receptor kinases, and molecular mechanism underlying β-arrestin-mediated signaling: We identify the interaction kinetics of CB1R and β-arrestin 1 during their endocytic trafficking as directly proportional to its efficacy. Finally, we demonstrate that signaling results in the control of genes clustered around prosurvival and proapoptotic functions among others. Together, these studies constitute a comprehensive description of β-arrestin-mediated signaling from CB1Rs and suggest modulation of receptor endocytic trafficking as a therapeutic approach to control β-arrestin-mediated signaling.
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Affiliation(s)
- Francheska Delgado-Peraza
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Kwang H Ahn
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Carlos Nogueras-Ortiz
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Imran N Mungrue
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Ken Mackie
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Debra A Kendall
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
| | - Guillermo A Yudowski
- Department of Anatomy and Neurobiology (F.D.-P., G.A.Y.) and Institute of Neurobiology (F.D.-P., C.N.-O., G.A.Y.), University of Puerto Rico - Medical Sciences Campus, San Juan, Puerto Rico; Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut (K.H.A., D.A.K.); Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (I.N.M.); and Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana (K.M.)
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132
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Endocytic pathways and endosomal trafficking: a primer. Wien Med Wochenschr 2016; 166:196-204. [PMID: 26861668 DOI: 10.1007/s10354-016-0432-7] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 01/05/2016] [Indexed: 01/05/2023]
Abstract
This brief overview of endocytic trafficking is written in honor of Renate Fuchs, who retires this year. In the mid-1980s, Renate pioneered studies on the ion-conducting properties of the recently discovered early and late endosomes and the mechanisms governing endosomal acidification. As described in this review, after uptake through one of many mechanistically distinct endocytic pathways, internalized proteins merge into a common early/sorting endosome. From there they again diverge along distinct sorting pathways, back to the cell surface, on to the trans-Golgi network or across polarized cells. Other transmembrane receptors are packaged into intraluminal vesicles of late endosomes/multivesicular bodies that eventually fuse with and deliver their content to lysosomes for degradation. Endosomal acidification, in part, determines sorting along this pathway. We describe other sorting machinery and mechanisms, as well as the rab proteins and phosphatidylinositol lipids that serve to dynamically define membrane compartments along the endocytic pathway.
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133
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Chhibber-Goel J, Coleman-Vaughan C, Agrawal V, Sawhney N, Hickey E, Powell JC, McCarthy JV. γ-Secretase Activity Is Required for Regulated Intramembrane Proteolysis of Tumor Necrosis Factor (TNF) Receptor 1 and TNF-mediated Pro-apoptotic Signaling. J Biol Chem 2016; 291:5971-5985. [PMID: 26755728 DOI: 10.1074/jbc.m115.679076] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Indexed: 12/27/2022] Open
Abstract
The γ-secretase protease and associated regulated intramembrane proteolysis play an important role in controlling receptor-mediated intracellular signaling events, which have a central role in Alzheimer disease, cancer progression, and immune surveillance. An increasing number of γ-secretase substrates have a role in cytokine signaling, including the IL-6 receptor, IL-1 receptor type I, and IL-1 receptor type II. In this study, we show that following TNF-converting enzyme-mediated ectodomain shedding of TNF type I receptor (TNFR1), the membrane-bound TNFR1 C-terminal fragment is subsequently cleaved by γ-secretase to generate a cytosolic TNFR1 intracellular domain. We also show that clathrin-mediated internalization of TNFR1 C-terminal fragment is a prerequisite for efficient γ-secretase cleavage of TNFR1. Furthermore, using in vitro and in vivo model systems, we show that in the absence of presenilin expression and γ-secretase activity, TNF-mediated JNK activation was prevented, assembly of the TNFR1 pro-apoptotic complex II was reduced, and TNF-induced apoptosis was inhibited. These observations demonstrate that TNFR1 is a γ-secretase substrate and suggest that γ-secretase cleavage of TNFR1 represents a new layer of regulation that links the presenilins and the γ-secretase protease to pro-inflammatory cytokine signaling.
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Affiliation(s)
- Jyoti Chhibber-Goel
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - Caroline Coleman-Vaughan
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - Vishal Agrawal
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - Neha Sawhney
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - Emer Hickey
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - James C Powell
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland
| | - Justin V McCarthy
- From the Signal Transduction Laboratory, School of Biochemistry and Cell Biology, ABCRF, 3.41 Western Gateway Building, Western Road, University College Cork, Cork T12 YN60, Ireland.
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135
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Abstract
G protein-coupled receptors (GPCRs) remain a major domain of pharmaceutical discovery. The identification of GPCR lead compounds and their optimization are now structure-based, thanks to advances in X-ray crystallography, molecular modeling, protein engineering and biophysical techniques. In silico screening provides useful hit molecules. New pharmacological approaches to tuning the pleotropic action of GPCRs include: allosteric modulators, biased ligands, GPCR heterodimer-targeted compounds, manipulation of polypharmacology, receptor antibodies and tailoring of drug molecules to fit GPCR pharmacogenomics. Measurements of kinetics and drug efficacy are factors influencing clinical success. With the exception of inhibitors of GPCR kinases, targeting of intracellular GPCR signaling or receptor cycling for therapeutic purposes remains a futuristic concept. New assay approaches are more efficient and multidimensional: cell-based, label-free, fluorescence-based assays, and biosensors. Tailoring GPCR drugs to a patient's genetic background is now being considered. Chemoinformatic tools can predict ADME-tox properties. New imaging technology visualizes drug action in vivo. Thus, there is reason to be optimistic that new technology for GPCR ligand discovery will help reverse the current narrowing of the pharmaceutical pipeline.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bldg. 8A, Rm. B1A-19, Bethesda, Maryland 20892, USA.
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136
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Gaudet HM, Cheng SB, Christensen EM, Filardo EJ. The G-protein coupled estrogen receptor, GPER: The inside and inside-out story. Mol Cell Endocrinol 2015; 418 Pt 3:207-19. [PMID: 26190834 DOI: 10.1016/j.mce.2015.07.016] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 07/15/2015] [Accepted: 07/15/2015] [Indexed: 02/06/2023]
Abstract
GPER possesses structural and functional characteristics shared by members of the G-protein-coupled receptor (GPCR) superfamily, the largest class of plasma membrane receptors. This newly appreciated estrogen receptor is localized predominately within intracellular membranes in most, but not all, cell types and its surface expression is modulated by steroid hormones and during tissue injury. An intracellular staining pattern is not unique among GPCRs, which employ a diverse array of molecular mechanisms that restrict cell surface expression and effectively regulating receptor binding and activation. The finding that GPER displays an intracellular predisposition has created some confusion as the estrogen-inducible transcription factors, ERα and ERβ, also reside intracellularly, and has led to complex suggestions of receptor interaction. GPER undergoes constitutive retrograde trafficking from the plasma membrane to the endoplasmic reticulum and recent studies indicate its interaction with PDZ binding proteins that sort transmembrane receptors to synaptosomes and endosomes. Genetic targeting and selective ligand approaches as well as cell models that express GPER in the absence of ERs clearly supports GPER as a bonafide "stand alone" receptor. Here, the molecular details that regulate GPER action, its cell biological activities and its implicated roles in physiological and pathological processes are reviewed.
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Affiliation(s)
- H M Gaudet
- Wheaton College, Department of Chemistry, Norton, MA, 02766, USA
| | - S B Cheng
- Women & Infants Hospital, Brown University, Providence, RI, 02903, USA
| | - E M Christensen
- Wheaton College, Department of Chemistry, Norton, MA, 02766, USA
| | - E J Filardo
- Rhode Island Hospital, Brown University, Providence, RI, 02903, USA.
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137
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Geppetti P, Veldhuis N, Lieu T, Bunnett N. G Protein-Coupled Receptors: Dynamic Machines for Signaling Pain and Itch. Neuron 2015; 88:635-49. [DOI: 10.1016/j.neuron.2015.11.001] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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138
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Felouzis V, Hermand P, de Laissardière GT, Combadière C, Deterre P. Comprehensive analysis of chemokine-induced cAMP-inhibitory responses using a real-time luminescent biosensor. Cell Signal 2015; 28:120-9. [PMID: 26515128 DOI: 10.1016/j.cellsig.2015.10.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 10/23/2015] [Indexed: 01/29/2023]
Abstract
Chemokine receptors are members of the G-protein-coupled receptor (GPCR) family coupled to members of the Gi class, whose primary function is to inhibit the cellular adenylate cyclase. We used a cAMP-related and PKA-based luminescent biosensor (GloSensor™ F-22) to monitor the real-time downstream response of chemokine receptors, especially CX3CR1 and CXCR4, after activation with their cognate ligands CX3CL1 and CXCL12. We found that the amplitudes and kinetic profiles of the chemokine responses were conserved in various cell types and were independent of the nature and concentration of the molecules used for cAMP prestimulation, including either the adenylate cyclase activator forskolin or ligands mediating Gs-mediated responses like prostaglandin E2 or beta-adrenergic agonist. We conclude that the cAMP chemokine response is robustly conserved in various inflammatory conditions. Moreover, the cAMP-related luminescent biosensor appears as a valuable tool to analyze the details of Gi-mediated cAMP-inhibitory cellular responses, even in native conditions and could help to decipher their precise role in cell function.
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Affiliation(s)
- Virginia Felouzis
- Sorbonne Universités, UPMC Université Paris 06, Inserm U 1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses, 91 Boulevard de l'Hôpital, F-75013 Paris, France
| | - Patricia Hermand
- Sorbonne Universités, UPMC Université Paris 06, Inserm U 1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses, 91 Boulevard de l'Hôpital, F-75013 Paris, France
| | - Guy Trambly de Laissardière
- Université de Cergy-Pontoise, CNRS, UMR 8089, Laboratoire de Physique Théorique et Modélisation, 2 Avenue A. Chauvin, F-95302 Cergy-Pontoise, France
| | - Christophe Combadière
- Sorbonne Universités, UPMC Université Paris 06, Inserm U 1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses, 91 Boulevard de l'Hôpital, F-75013 Paris, France
| | - Philippe Deterre
- Sorbonne Universités, UPMC Université Paris 06, Inserm U 1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses, 91 Boulevard de l'Hôpital, F-75013 Paris, France.
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139
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Gardella TJ, Vilardaga JP. International Union of Basic and Clinical Pharmacology. XCIII. The parathyroid hormone receptors--family B G protein-coupled receptors. Pharmacol Rev 2015; 67:310-37. [PMID: 25713287 DOI: 10.1124/pr.114.009464] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The type-1 parathyroid hormone receptor (PTHR1) is a family B G protein-coupled receptor (GPCR) that mediates the actions of two polypeptide ligands; parathyroid hormone (PTH), an endocrine hormone that regulates the levels of calcium and inorganic phosphate in the blood by acting on bone and kidney, and PTH-related protein (PTHrP), a paracrine-factor that regulates cell differentiation and proliferation programs in developing bone and other tissues. The type-2 parathyroid hormone receptor (PTHR2) binds a peptide ligand, called tuberoinfundibular peptide-39 (TIP39), and while the biologic role of the PTHR2/TIP39 system is not as defined as that of the PTHR1, it likely plays a role in the central nervous system as well as in spermatogenesis. Mechanisms of action at these receptors have been explored through a variety of pharmacological and biochemical approaches, and the data obtained support a basic "two-site" mode of ligand binding now thought to be used by each of the family B peptide hormone GPCRs. Recent crystallographic studies on the family B GPCRs are providing new insights that help to further refine the specifics of the overall receptor architecture and modes of ligand docking. One intriguing pharmacological finding for the PTHR1 is that it can form surprisingly stable complexes with certain PTH/PTHrP ligand analogs and thereby mediate markedly prolonged cell signaling responses that persist even when the bulk of the complexes are found in internalized vesicles. The PTHR1 thus appears to be able to activate the Gα(s)/cAMP pathway not only from the plasma membrane but also from the endosomal domain. The cumulative findings could have an impact on efforts to develop new drug therapies for the PTH receptors.
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Affiliation(s)
- Thomas J Gardella
- Endocrine Unit, Massachusetts General Hospital, Boston, Massachusetts (T.J.G.); and Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (J.-P.V.)
| | - Jean-Pierre Vilardaga
- Endocrine Unit, Massachusetts General Hospital, Boston, Massachusetts (T.J.G.); and Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (J.-P.V.)
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140
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Tewari R, Bachert C, Linstedt AD. Induced oligomerization targets Golgi proteins for degradation in lysosomes. Mol Biol Cell 2015; 26:4427-37. [PMID: 26446839 PMCID: PMC4666137 DOI: 10.1091/mbc.e15-04-0207] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 09/29/2015] [Indexed: 01/07/2023] Open
Abstract
Oligomerization or homotypic clustering diverts Golgi membrane proteins into the canonical GGA1/clathrin-dependent Golgi-to-lysosome pathway revealing the presence of cellular quality control that could be useful for therapies designed to down-regulate specific proteins in the secretory pathway. Manganese protects cells against forms of Shiga toxin by down-regulating the cycling Golgi protein GPP130. Down-regulation occurs when Mn binding causes GPP130 to oligomerize and traffic to lysosomes. To determine how GPP130 is redirected to lysosomes, we tested the role of GGA1 and clathrin, which mediate sorting in the canonical Golgi-to-lysosome pathway. GPP130 oligomerization was induced using either Mn or a self-interacting version of the FKBP domain. Inhibition of GGA1 or clathrin specifically blocked GPP130 redistribution, suggesting recognition of the aggregated GPP130 by the GGA1/clathrin-sorting complex. Unexpectedly, however, GPP130’s cytoplasmic domain was not required, and redistribution also occurred after removal of GPP130 sequences needed for its normal cycling. Therefore, to test whether aggregate recognition might be a general phenomenon rather than one involving a specific GPP130 determinant, we induced homo-oligomerization of two unrelated Golgi-targeted constructs using the FKBP strategy. These were targeted to the cis- and trans-Golgi, respectively, using domains from mannosidase-1 and galactosyltransferase. Significantly, upon oligomerization, each redistributed to peripheral punctae and was degraded. This occurred in the absence of detectable UPR activation. These findings suggest the unexpected presence of quality control in the Golgi that recognizes aggregated Golgi proteins and targets them for degradation in lysosomes.
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Affiliation(s)
- Ritika Tewari
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Collin Bachert
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Adam D Linstedt
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
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141
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Irannejad R, Tsvetanova NG, Lobingier BT, von Zastrow M. Effects of endocytosis on receptor-mediated signaling. Curr Opin Cell Biol 2015; 35:137-43. [PMID: 26057614 PMCID: PMC4529812 DOI: 10.1016/j.ceb.2015.05.005] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/18/2015] [Accepted: 05/20/2015] [Indexed: 01/31/2023]
Abstract
Cellular mechanisms of membrane traffic and signal transduction are deeply interconnected. The present review discusses how membrane trafficking in the endocytic pathway impacts receptor-mediated signaling. Examples of recent progress are highlighted, focusing on the endocytosis-signaling nexus in mammals.
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Affiliation(s)
- Roshanak Irannejad
- Departments of Psychiatry and of Cellular & Molecular Pharmacology, University of California, San Francisco School of Medicine, 600 16th Street, San Francisco CA 94158-2140 USA
| | - Nikoleta G. Tsvetanova
- Departments of Psychiatry and of Cellular & Molecular Pharmacology, University of California, San Francisco School of Medicine, 600 16th Street, San Francisco CA 94158-2140 USA
| | - Braden T. Lobingier
- Departments of Psychiatry and of Cellular & Molecular Pharmacology, University of California, San Francisco School of Medicine, 600 16th Street, San Francisco CA 94158-2140 USA
| | - Mark von Zastrow
- Departments of Psychiatry and of Cellular & Molecular Pharmacology, University of California, San Francisco School of Medicine, 600 16th Street, San Francisco CA 94158-2140 USA
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142
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Stoddart LA, Kilpatrick LE, Briddon SJ, Hill SJ. Probing the pharmacology of G protein-coupled receptors with fluorescent ligands. Neuropharmacology 2015; 98:48-57. [PMID: 25979488 DOI: 10.1016/j.neuropharm.2015.04.033] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/23/2015] [Accepted: 04/29/2015] [Indexed: 01/01/2023]
Abstract
G protein-coupled receptors control a wide range of physiological processes and are the target for many clinically used drugs. Understanding the way in which receptors bind agonists and antagonists, their organisation in the membrane and their regulation after agonist binding are important properties which are key to developing new drugs. One way to achieve this knowledge is through the use of fluorescent ligands, which have been used to study the expression and function of receptors in endogenously expressing systems. Fluorescent ligands with appropriate imaging properties can be used in conjunction with confocal microscopy to investigate the regulation of receptors after activation. Alternatively, through the use of single molecule microscopy, they can probe the spatial organisation of receptors within the membrane. This review focuses on the techniques in which fluorescent ligands have been used and the novel aspects of G protein-coupled receptor pharmacology which have been uncovered. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'.
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Affiliation(s)
- Leigh A Stoddart
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Laura E Kilpatrick
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Hill
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
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143
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Walther C, Ferguson SSG. Minireview: Role of intracellular scaffolding proteins in the regulation of endocrine G protein-coupled receptor signaling. Mol Endocrinol 2015; 29:814-30. [PMID: 25942107 DOI: 10.1210/me.2015-1091] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The majority of hormones stimulates and mediates their signal transduction via G protein-coupled receptors (GPCRs). The signal is transmitted into the cell due to the association of the GPCRs with heterotrimeric G proteins, which in turn activates an extensive array of signaling pathways to regulate cell physiology. However, GPCRs also function as scaffolds for the recruitment of a variety of cytoplasmic protein-interacting proteins that bind to both the intracellular face and protein interaction motifs encoded by GPCRs. The structural scaffolding of these proteins allows GPCRs to recruit large functional complexes that serve to modulate both G protein-dependent and -independent cellular signaling pathways and modulate GPCR intracellular trafficking. This review focuses on GPCR interacting PSD95-disc large-zona occludens domain containing scaffolds in the regulation of endocrine receptor signaling as well as their potential role as therapeutic targets for the treatment of endocrinopathies.
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Affiliation(s)
- Cornelia Walther
- J. Allyn Taylor Centre for Cell Biology (C.W., S.S.G.F.), Robarts Research Institute, and Department of Physiology and Pharmacology (S.S.G.F.), University of Western Ontario, London, Ontario, Canada N6A 5K8
| | - Stephen S G Ferguson
- J. Allyn Taylor Centre for Cell Biology (C.W., S.S.G.F.), Robarts Research Institute, and Department of Physiology and Pharmacology (S.S.G.F.), University of Western Ontario, London, Ontario, Canada N6A 5K8
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144
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Trafficking of β-Adrenergic Receptors: Implications in Intracellular Receptor Signaling. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 132:151-88. [PMID: 26055058 DOI: 10.1016/bs.pmbts.2015.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
β-Adrenergic receptors (βARs), prototypical G-protein-coupled receptors, play a pivotal role in regulating neuronal and cardiovascular responses to catecholamines during stress. Agonist-induced receptor endocytosis is traditionally considered as a primary mechanism to turn off the receptor signaling (or receptor desensitization). However, recent progress suggests that intracellular trafficking of βAR presents a mean to translocate receptor signaling machinery to intracellular organelles/compartments while terminating the signaling at the cell surface. Moreover, the apparent multidimensionality of ligand efficacy in space and time in a cell has forecasted exciting pathophysiological implications, which are just beginning to be explored. As we begin to understand how these pathways impact downstream cellular programs, this will have significant implications for a number of pathophysiological conditions in heart and other systems, that in turn open up new therapeutic opportunities.
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145
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Wang D, Zhao WL, Cai MJ, Wang JX, Zhao XF. G-protein-coupled receptor controls steroid hormone signaling in cell membrane. Sci Rep 2015; 5:8675. [PMID: 25728569 DOI: 10.1038/srep08675] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/30/2014] [Indexed: 12/21/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are involved in animal steroid hormone signaling, but their mechanism is unclear. In this research, we report that a GPCR called ErGPCR-2 controls steroid hormone 20-hydroxyecdysone (20E) signaling in the cell membrane of the lepidopteran insect Helicoverpa armigera. ErGPCR-2 was highly expressed during molting and metamorphosis. 20E, via ErGPCR-2, regulated rapid intracellular calcium increase, protein phosphorylation, gene transcription, and insect metamorphosis. ErGPCR-2 was located in the cell surface and was internalized by 20E induction. GPCR kinase 2 participated in 20E-induced ErGPCR-2 phosphorylation and internalization. The internalized ErGPCR-2 was degraded by proteases to desensitize 20E signaling. ErGPCR-2 knockdown suppressed the entrance of 20E analog [(3)H] ponasterone A ([(3)H]Pon A) into the cells. ErGPCR-2 overexpression or blocking of ErGPCR-2 internalization increased the entrance of [(3)H]Pon A into the cells. However, ErGPCR-2 did not bind to [(3)H]Pon A. Results suggest that ErGPCR-2 transmits steroid hormone 20E signaling and controls 20E entrance into cells in the cell membrane.
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Affiliation(s)
- Di Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan 250100, China
| | - Wen-Li Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan 250100, China
| | - Mei-Juan Cai
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan 250100, China
| | - Jin-Xing Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan 250100, China
| | - Xiao-Fan Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan 250100, China
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146
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Tsvetanova NG, Irannejad R, von Zastrow M. G protein-coupled receptor (GPCR) signaling via heterotrimeric G proteins from endosomes. J Biol Chem 2015; 290:6689-96. [PMID: 25605726 DOI: 10.1074/jbc.r114.617951] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Some G protein-coupled receptors (GPCRs), in addition to activating heterotrimeric G proteins in the plasma membrane, appear to elicit a "second wave" of G protein activation after ligand-induced internalization. We briefly summarize evidence supporting this view and then discuss what is presently known about the functional significance of GPCR-G protein activation in endosomes. Endosomal activation can shape the cellular response temporally by prolonging its overall duration, and may shape the response spatially by moving the location of intracellular second messenger production relative to effectors.
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Affiliation(s)
| | | | - Mark von Zastrow
- From the Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158
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147
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Mølleskov-Jensen AS, Oliveira MT, Farrell HE, Davis-Poynter N. Virus-Encoded 7 Transmembrane Receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 129:353-93. [DOI: 10.1016/bs.pmbts.2014.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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148
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Roed SN, Nøhr AC, Wismann P, Iversen H, Bräuner-Osborne H, Knudsen SM, Waldhoer M. Functional consequences of glucagon-like peptide-1 receptor cross-talk and trafficking. J Biol Chem 2014; 290:1233-43. [PMID: 25451942 DOI: 10.1074/jbc.m114.592436] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The signaling capacity of seven-transmembrane/G-protein-coupled receptors (7TM/GPCRs) can be regulated through ligand-mediated receptor trafficking. Classically, the recycling of internalized receptors is associated with resensitization, whereas receptor degradation terminates signaling. We have shown previously that the incretin glucagon-like peptide-1 receptor (GLP-1R) internalizes fast and is primarily resensitized through recycling back to the cell surface. GLP-1R is expressed in pancreatic islets together with the closely related glucose-dependent insulinotropic polypeptide (GIPR) and glucagon (GCGR) receptors. The interaction and cross-talk between coexpressed receptors is a wide phenomenon of the 7TM/GPCR superfamily. Numerous reports show functional consequences for signaling and trafficking of the involved receptors. On the basis of the high structural similarity and tissue coexpression, we here investigated the potential cross-talk between GLP-1R and GIPR or GCGR in both trafficking and signaling pathways. Using a real-time time-resolved FRET-based internalization assay, we show that GLP-1R, GIPR, and GCGR internalize with differential properties. Remarkably, upon coexpression of the internalizing GLP-1R and the non-internalizing GIPR, GLP-1-mediated GLP-1R internalization was impaired in a GIPR concentration-dependent manner. As a functional consequence of such impaired internalization capability, GLP-1-mediated GLP-1R signaling was abrogated. A similar compromised signaling was found when GLP-1R internalization was abrogated by a dominant-negative version of dynamin (dynamin-1 K44E), which provides a mechanistic link between GLP-1R trafficking and signaling. This study highlights the importance of receptor internalization for full functionality of GLP-1R. Moreover, cross-talk between the two incretin receptors GLP-1R and GIPR is shown to alter receptor trafficking with functional consequences for GLP-1R signaling.
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Affiliation(s)
| | - Anne Cathrine Nøhr
- the Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1165 Copenhagen, Denmark
| | - Pernille Wismann
- From the Department of Incretin Biology, Novo Nordisk A/S, 2760 Maaloev and
| | - Helle Iversen
- From the Department of Incretin Biology, Novo Nordisk A/S, 2760 Maaloev and
| | - Hans Bräuner-Osborne
- the Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1165 Copenhagen, Denmark
| | | | - Maria Waldhoer
- From the Department of Incretin Biology, Novo Nordisk A/S, 2760 Maaloev and
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149
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Triest S, Wohlkönig A, Pardon E, Steyaert J. Production, crystallization and preliminary X-ray diffraction of the Gαs α-helical domain in complex with a nanobody. Acta Crystallogr F Struct Biol Commun 2014; 70:1504-7. [PMID: 25372817 PMCID: PMC4231852 DOI: 10.1107/s2053230x14020962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 09/19/2014] [Indexed: 11/10/2022] Open
Abstract
GPCR-G-protein complexes are one of the most important components of cell-signalling cascades. Extracellular signals are sensed by membrane-associated G-protein-coupled receptors (GPCRs) and transduced via G proteins towards intracellular effector molecules. Structural studies of these transient complexes are crucial to understand the molecular details of these interactions. Although a nucleotide-free GPCR-G-protein complex is stable, it is not an ideal sample for crystallization owing to the intrinsic mobility of the Gαs α-helical domain (AHD). To stabilize GPCR-G-protein complexes in a nucleotide-free form, nanobodies were selected that target the flexible GαsAHD. One of these nanobodies, CA9177, was co-crystallized with the GαsAHD. Initial crystals were obtained using the sitting-drop method in a sparse-matrix screen and further optimized. The crystals diffracted to 1.59 Å resolution and belonged to the monoclinic space group P2₁, with unit-cell parameters a=44.07, b=52.55, c=52.66 Å, α=90.00, β=107.89, γ=90.00°. The structure of this specific nanobody reveals its binding epitope on GαsAHD and will help to determine whether this nanobody could be used as crystallization chaperone for GPCR-G-protein complexes.
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Affiliation(s)
- Sarah Triest
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnology (VIB), Pleinlaan 2, 1050 Elsene, Belgium
| | - Alexandre Wohlkönig
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnology (VIB), Pleinlaan 2, 1050 Elsene, Belgium
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnology (VIB), Pleinlaan 2, 1050 Elsene, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnology (VIB), Pleinlaan 2, 1050 Elsene, Belgium
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150
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Structured and disordered facets of the GPCR fold. Curr Opin Struct Biol 2014; 27:129-37. [PMID: 25198166 DOI: 10.1016/j.sbi.2014.08.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 07/28/2014] [Accepted: 08/05/2014] [Indexed: 01/14/2023]
Abstract
The seven-transmembrane (7TM) helix fold of G-protein coupled receptors (GPCRs) has been adapted for a wide variety of physiologically important signaling functions. Here, we discuss the diversity in the structured and disordered regions of GPCRs based on the recently published crystal structures and sequence analysis of all human GPCRs. A comparison of the structures of rhodopsin-like receptors (class A), secretin-like receptors (class B), metabotropic receptors (class C) and frizzled receptors (class F) shows that the relative arrangement of the transmembrane helices is conserved across all four GPCR classes although individual receptors can be activated by ligand binding at varying positions within and around the transmembrane helical bundle. A systematic analysis of GPCR sequences reveals the presence of disordered segments in the cytoplasmic side, abundant post-translational modification sites, evidence for alternative splicing and several putative linear peptide motifs that have the potential to mediate interactions with cytosolic proteins. While the structured regions permit the receptor to bind diverse ligands, the disordered regions appear to have an underappreciated role in modulating downstream signaling in response to the cellular state. An integrated paradigm combining the knowledge of structured and disordered regions is imperative for gaining a holistic understanding of the GPCR (un)structure-function relationship.
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