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Pakharukova N, Thomas BN, Bansia H, Li L, Abzalimov RR, Kim J, Kahsai AW, Pani B, Bassford DK, Liu S, Zhang X, des Georges A, Lefkowitz RJ. Beta-arrestin 1 mediated Src activation via Src SH3 domain revealed by cryo-electron microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.31.605623. [PMID: 39131402 PMCID: PMC11312540 DOI: 10.1101/2024.07.31.605623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Beta-arrestins (βarrs) are key regulators and transducers of G-protein coupled receptor signaling; however, little is known of how βarrs communicate with their downstream effectors. Here, we use cryo-electron microscopy to elucidate how βarr1 recruits and activates non-receptor tyrosine kinase Src. βarr1 binds Src SH3 domain via two distinct sites: a polyproline site in the N-domain and a non-proline site in the central crest region. At both sites βarr1 interacts with the aromatic surface of SH3 which is critical for Src autoinhibition, suggesting that βarr1 activates Src by SH3 domain displacement. Binding of SH3 to the central crest region induces structural rearrangements in the β-strand V, finger, and middle loops of βarr1 and interferes with βarr1 coupling to the receptor core potentially impacting receptor desensitization and downstream signaling.
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Affiliation(s)
- Natalia Pakharukova
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
- Howard Hughes Medical Institute, Duke University Medical Center; Durham, NC 27710, USA
| | - Brittany N Thomas
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
- Howard Hughes Medical Institute, Duke University Medical Center; Durham, NC 27710, USA
| | - Harsh Bansia
- Structural Biology Initiative, CUNY Advanced Science Research Center; New York, NY 10031, USA
| | - Linus Li
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Rinat R Abzalimov
- Structural Biology Initiative, CUNY Advanced Science Research Center; New York, NY 10031, USA
| | - Jihee Kim
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Alem W Kahsai
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Dana K Bassford
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
- Howard Hughes Medical Institute, Duke University Medical Center; Durham, NC 27710, USA
| | - Shibo Liu
- Structural Biology Initiative, CUNY Advanced Science Research Center; New York, NY 10031, USA
| | - Xingdong Zhang
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Amedee des Georges
- Structural Biology Initiative, CUNY Advanced Science Research Center; New York, NY 10031, USA
- Department of Chemistry and Biochemistry, City College of New York; New York, NY 10031, USA
- Biochemistry and Chemistry PhD Programs, Graduate Center, City University of New York; New York, NY 10031, USA
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
- Howard Hughes Medical Institute, Duke University Medical Center; Durham, NC 27710, USA
- Department of Biochemistry, Duke University Medical Center; Durham, NC 27710, USA
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2
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Gurevich VV. Arrestins: A Small Family of Multi-Functional Proteins. Int J Mol Sci 2024; 25:6284. [PMID: 38892473 PMCID: PMC11173308 DOI: 10.3390/ijms25116284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 05/24/2024] [Accepted: 05/31/2024] [Indexed: 06/21/2024] Open
Abstract
The first member of the arrestin family, visual arrestin-1, was discovered in the late 1970s. Later, the other three mammalian subtypes were identified and cloned. The first described function was regulation of G protein-coupled receptor (GPCR) signaling: arrestins bind active phosphorylated GPCRs, blocking their coupling to G proteins. It was later discovered that receptor-bound and free arrestins interact with numerous proteins, regulating GPCR trafficking and various signaling pathways, including those that determine cell fate. Arrestins have no enzymatic activity; they function by organizing multi-protein complexes and localizing their interaction partners to particular cellular compartments. Today we understand the molecular mechanism of arrestin interactions with GPCRs better than the mechanisms underlying other functions. However, even limited knowledge enabled the construction of signaling-biased arrestin mutants and extraction of biologically active monofunctional peptides from these multifunctional proteins. Manipulation of cellular signaling with arrestin-based tools has research and likely therapeutic potential: re-engineered proteins and their parts can produce effects that conventional small-molecule drugs cannot.
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3
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Backe SJ, Votra SD, Stokes MP, Sebestyén E, Castelli M, Torielli L, Colombo G, Woodford MR, Mollapour M, Bourboulia D. PhosY-secretome profiling combined with kinase-substrate interaction screening defines active c-Src-driven extracellular signaling. Cell Rep 2023; 42:112539. [PMID: 37243593 PMCID: PMC10569185 DOI: 10.1016/j.celrep.2023.112539] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/07/2023] [Accepted: 05/03/2023] [Indexed: 05/29/2023] Open
Abstract
c-Src tyrosine kinase is a renowned key intracellular signaling molecule and a potential target for cancer therapy. Secreted c-Src is a recent observation, but how it contributes to extracellular phosphorylation remains elusive. Using a series of domain deletion mutants, we show that the N-proximal region of c-Src is essential for its secretion. The tissue inhibitor of metalloproteinases 2 (TIMP2) is an extracellular substrate of c-Src. Limited proteolysis-coupled mass spectrometry and mutagenesis studies verify that the Src homology 3 (SH3) domain of c-Src and the P31VHP34 motif of TIMP2 are critical for their interaction. Comparative phosphoproteomic analyses identify an enrichment of PxxP motifs in phosY-containing secretomes from c-Src-expressing cells with cancer-promoting roles. Inhibition of extracellular c-Src using custom SH3-targeting antibodies disrupt kinase-substrate complexes and inhibit cancer cell proliferation. These findings point toward an intricate role for c-Src in generating phosphosecretomes, which will likely influence cell-cell communication, particularly in c-Src-overexpressing cancers.
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Affiliation(s)
- Sarah J Backe
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - SarahBeth D Votra
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | | | | | - Matteo Castelli
- Dipartimento di Chimica, Università di Pavia, 27100 Pavia, Italy
| | - Luca Torielli
- Dipartimento di Chimica, Università di Pavia, 27100 Pavia, Italy
| | - Giorgio Colombo
- Dipartimento di Chimica, Università di Pavia, 27100 Pavia, Italy
| | - Mark R Woodford
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Mehdi Mollapour
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Dimitra Bourboulia
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA.
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4
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Zhang H, Ren L, Shivnaraine RV. Targeting GPCRs to treat cardiac fibrosis. Front Cardiovasc Med 2022; 9:1011176. [PMID: 36277752 PMCID: PMC9582444 DOI: 10.3389/fcvm.2022.1011176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Cardiac fibrosis occurs ubiquitously in ischemic heart failure, genetic cardiomyopathies, diabetes mellitus, and aging. It triggers myocardial stiffness, which impairs cardiac function, ultimately progressing to end-stage heart failure and increased mortality. Although several targets for anti-fibrotic therapies have been identified, including TGF-β and receptor tyrosine kinase, there is currently no FDA-approved drug specifically targeting cardiac fibrosis. G protein-coupled receptors (GPCRs) are integral, multipass membrane-bound receptors that exhibit diverse and cell-specific expression, offering novel and unrealized therapeutic targets for cardiac fibrosis. This review highlights the emerging roles of several GPCRs and briefly explores their downstream pathways that are crucial in cardiac fibrosis. We will not only provide an overview of the GPCRs expressed on cardiac fibroblasts that are directly involved in myofibroblast activation but also describe those GPCRs which contribute to cardiac fibrosis via indirect crosstalk mechanisms. We also discuss the challenges of identifying novel effective therapies for cardiac fibrosis and offer strategies to circumvent these challenges.
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Affiliation(s)
- Hao Zhang
- Department of Medicine, Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States,*Correspondence: Hao Zhang
| | - Lu Ren
- Department of Medicine, Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States
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5
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Jiang H, Galtes D, Wang J, Rockman HA. G protein-coupled receptor signaling: transducers and effectors. Am J Physiol Cell Physiol 2022; 323:C731-C748. [PMID: 35816644 PMCID: PMC9448338 DOI: 10.1152/ajpcell.00210.2022] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/27/2022] [Accepted: 07/10/2022] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCRs) are of considerable interest due to their importance in a wide range of physiological functions and in a large number of Food and Drug Administration (FDA)-approved drugs as therapeutic entities. With continued study of their function and mechanism of action, there is a greater understanding of how effector molecules interact with a receptor to initiate downstream effector signaling. This review aims to explore the signaling pathways, dynamic structures, and physiological relevance in the cardiovascular system of the three most important GPCR signaling effectors: heterotrimeric G proteins, GPCR kinases (GRKs), and β-arrestins. We will first summarize their prominent roles in GPCR pharmacology before transitioning into less well-explored areas. As new technologies are developed and applied to studying GPCR structure and their downstream effectors, there is increasing appreciation for the elegance of the regulatory mechanisms that mediate intracellular signaling and function.
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Affiliation(s)
- Haoran Jiang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Daniella Galtes
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Jialu Wang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina
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6
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Wedegaertner H, Pan WA, Gonzalez CC, Gonzalez DJ, Trejo J. The α-Arrestin ARRDC3 Is an Emerging Multifunctional Adaptor Protein in Cancer. Antioxid Redox Signal 2022; 36:1066-1079. [PMID: 34465145 PMCID: PMC9127825 DOI: 10.1089/ars.2021.0193] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Significance: Adaptor proteins control the spatiotemporal dynamics of cellular signaling. Dysregulation of adaptor protein function can cause aberrant cell signaling and promote cancer. The arrestin family of adaptor proteins are known to regulate signaling by the superfamily of G protein-coupled receptors (GPCRs). The GPCRs are highly druggable and implicated in cancer progression. However, the molecular mechanisms responsible for arrestin dysregulation and the impact on GPCR function in cancer have yet to be fully elucidated. Recent Advances: A new family of mammalian arrestins, termed the α-arrestins, was recently discovered. The α-arrestin, arrestin domain-containing protein 3 (ARRDC3), in particular, has been identified as a tumor suppressor and is reported to control cellular signaling of GPCRs in cancer. Critical Issues: Compared with the extensively studied mammalian β-arrestins, there is limited information regarding the regulatory mechanisms that control α-arrestin activation and function. Here, we discuss the molecular mechanisms that regulate ARRDC3, which include post-translational modifications such as phosphorylation and ubiquitination. We also provide evidence that ARRDC3 can interact with a wide array of proteins that control diverse biological functions. Future Directions: ARRDC3 interacts with numerous proteins and is likely to display diverse functions in cancer, metabolic disease, and other syndromes. Thus, understanding the regulatory mechanisms of ARRDC3 activity in various cellular contexts is critically important. Recent studies suggest that α-arrestins may be regulated through post-translational modification, which is known to impact adaptor protein function. However, additional studies are needed to determine how these regulatory mechanisms affect ARRDC3 tumor suppressor function. Antioxid. Redox Signal. 36, 1066-1079.
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Affiliation(s)
- Helen Wedegaertner
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California, USA.,Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, California, USA
| | - Wen-An Pan
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Carlos C Gonzalez
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - David J Gonzalez
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California, USA.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA
| | - JoAnn Trejo
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California, USA
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7
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Perez I, Berndt S, Agarwal R, Castro MA, Vishnivetskiy SA, Smith JC, Sanders CR, Gurevich VV, Iverson T. A Model for the Signal Initiation Complex Between Arrestin-3 and the Src Family Kinase Fgr. J Mol Biol 2022; 434:167400. [PMID: 34902430 PMCID: PMC8752512 DOI: 10.1016/j.jmb.2021.167400] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/24/2021] [Accepted: 12/04/2021] [Indexed: 02/01/2023]
Abstract
Arrestins regulate a wide range of signaling events, most notably when bound to active G protein-coupled receptors (GPCRs). Among the known effectors recruited by GPCR-bound arrestins are Src family kinases, which regulate cellular growth and proliferation. Here, we focus on arrestin-3 interactions with Fgr kinase, a member of the Src family. Previous reports demonstrated that Fgr exhibits high constitutive activity, but can be further activated by both arrestin-dependent and arrestin-independent pathways. We report that arrestin-3 modulates Fgr activity with a hallmark bell-shaped concentration-dependence, consistent with a role as a signaling scaffold. We further demonstrate using NMR spectroscopy that a polyproline motif within arrestin-3 interacts directly with the SH3 domain of Fgr. To provide a framework for this interaction, we determined the crystal structure of the Fgr SH3 domain at 1.9 Å resolution and developed a model for the GPCR-arrestin-3-Fgr complex that is supported by mutagenesis. This model suggests that Fgr interacts with arrestin-3 at multiple sites and is consistent with the locations of disease-associated Fgr mutations. Collectively, these studies provide a structural framework for arrestin-dependent activation of Fgr.
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Affiliation(s)
- Ivette Perez
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-0146;,Center for Structural Biology, Nashville, TN 37232-0146
| | - Sandra Berndt
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-0146;,Center for Structural Biology, Nashville, TN 37232-0146
| | - Rupesh Agarwal
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996;,UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, TN
| | - Manuel A. Castro
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-0146;,Center for Structural Biology, Nashville, TN 37232-0146
| | | | - Jeremy C. Smith
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996;,UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, TN
| | - Charles R. Sanders
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-0146;,Center for Structural Biology, Nashville, TN 37232-0146
| | | | - T.M. Iverson
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-0146;,Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-0146;,Center for Structural Biology, Nashville, TN 37232-0146;,Vanderbilt Institute of Chemical Biology, Nashville, TN 37232-0146
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8
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Targeting GPCRs and Their Signaling as a Therapeutic Option in Melanoma. Cancers (Basel) 2022; 14:cancers14030706. [PMID: 35158973 PMCID: PMC8833576 DOI: 10.3390/cancers14030706] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 01/27/2022] [Accepted: 01/27/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary Sixteen G-protein-coupled receptors (GPCRs) have been involved in melanogenesis or melanomagenesis. Here, we review these GPCRs, their associated signaling, and therapies. Abstract G-protein-coupled receptors (GPCRs) serve prominent roles in melanocyte lineage physiology, with an impact at all stages of development, as well as on mature melanocyte functions. GPCR ligands are present in the skin and regulate melanocyte homeostasis, including pigmentation. The role of GPCRs in the regulation of pigmentation and, consequently, protection against external aggression, such as ultraviolet radiation, has long been established. However, evidence of new functions of GPCRs directly in melanomagenesis has been highlighted in recent years. GPCRs are coupled, through their intracellular domains, to heterotrimeric G-proteins, which induce cellular signaling through various pathways. Such signaling modulates numerous essential cellular processes that occur during melanomagenesis, including proliferation and migration. GPCR-associated signaling in melanoma can be activated by the binding of paracrine factors to their receptors or directly by activating mutations. In this review, we present melanoma-associated alterations of GPCRs and their downstream signaling and discuss the various preclinical models used to evaluate new therapeutic approaches against GPCR activity in melanoma. Recent striking advances in our understanding of the structure, function, and regulation of GPCRs will undoubtedly broaden melanoma treatment options in the future.
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9
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Song HE, Lee Y, Kim E, Cho CY, Jung O, Lee D, Lee EG, Nam SH, Kang M, Macalino SJY, Kim JE, Jung JW, Kwon SW, Choi S, Lee JW. N-terminus-independent activation of c-Src via binding to a tetraspan(in) TM4SF5 in hepatocellular carcinoma is abolished by the TM4SF5 C-terminal peptide application. Theranostics 2021; 11:8092-8111. [PMID: 34335982 PMCID: PMC8315060 DOI: 10.7150/thno.58739] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/25/2021] [Indexed: 12/24/2022] Open
Abstract
Active c-Src non-receptor tyrosine kinase localizes to the plasma membrane via N-terminal lipid modification. Membranous c-Src causes cancer initiation and progression. Even though transmembrane 4 L six family member 5 (TM4SF5), a tetraspan(in), can be involved in this mechanism, the molecular and structural influence of TM4SF5 on c-Src remains unknown. Methods: Here, we investigated molecular and structural details by which TM4SF5 regulated c-Src devoid of its N-terminus and how cell-penetrating peptides were able to interrupt c-Src activation via interference of c-Src-TM4SF5 interaction in hepatocellular carcinoma models. Results: The TM4SF5 C-terminus efficiently bound the c-Src SH1 kinase domain, efficiently to the inactively-closed form. The complex involved protein tyrosine phosphatase 1B able to dephosphorylate Tyr530. The c-Src SH1 domain alone, even in a closed form, bound TM4SF5 to cause c-Src Tyr419 and FAK Y861 phosphorylation. Homology modeling and molecular dynamics simulation studies predicted the directly interfacing residues, which were further validated by mutational studies. Cell penetration of TM4SF5 C-terminal peptides blocked the interaction of TM4SF5 with c-Src and prevented c-Src-dependent tumor initiation and progression in vivo. Conclusions: Collectively, these data demonstrate that binding of the TM4SF5 C-terminus to the kinase domain of inactive c-Src leads to its activation. Because this binding can be abolished by cell-penetrating peptides containing the TM4SF5 C-terminus, targeting this direct interaction may be an effective strategy for developing therapeutics that block the development and progression of hepatocellular carcinoma.
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Affiliation(s)
- Haeng Eun Song
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Yoonji Lee
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Eunmi Kim
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Chang Yun Cho
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Oisun Jung
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Doohyung Lee
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun Goo Lee
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Seo Hee Nam
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Minkyung Kang
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Stephani Joy Y. Macalino
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Ji Eon Kim
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jae Woo Jung
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Interdisciplinary Program in Genetic Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Sung Won Kwon
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Sun Choi
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jung Weon Lee
- Department of Pharmacy, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
- Interdisciplinary Program in Genetic Engineering, Seoul National University, Seoul 08826, Republic of Korea
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10
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Wanka L, Behr V, Beck-Sickinger AG. Arrestin-dependent internalization of rhodopsin-like G protein-coupled receptors. Biol Chem 2021; 403:133-149. [PMID: 34036761 DOI: 10.1515/hsz-2021-0128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/28/2021] [Indexed: 01/14/2023]
Abstract
The internalization of G protein-coupled receptors (GPCRs) is an important mechanism regulating the signal strength and limiting the opportunity of receptor activation. Based on the importance of GPCRs, the detailed knowledge about the regulation of signal transduction is crucial. Here, current knowledge about the agonist-induced, arrestin-dependent internalization process of rhodopsin-like GPCRs is reviewed. Arrestins are conserved molecules that act as key players within the internalization process of many GPCRs. Based on highly conserved structural characteristics within the rhodopsin-like GPCRs, the identification of arrestin interaction sites in model systems can be compared and used for the investigation of internalization processes of other receptors. The increasing understanding of this essential regulation mechanism of receptors can be used for drug development targeting rhodopsin-like GPCRs. Here, we focus on the neuropeptide Y receptor family, as these receptors transmit various physiological processes such as food intake, energy homeostasis, and regulation of emotional behavior, and are further involved in pathophysiological processes like cancer, obesity and mood disorders. Hence, this receptor family represents an interesting target for the development of novel therapeutics requiring the understanding of the regulatory mechanisms influencing receptor mediated signaling.
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Affiliation(s)
- Lizzy Wanka
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Brüderstr. 34, D-04103Leipzig, Germany
| | - Victoria Behr
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Brüderstr. 34, D-04103Leipzig, Germany
| | - Annette G Beck-Sickinger
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Brüderstr. 34, D-04103Leipzig, Germany
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11
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Aydin Y, Coin I. Biochemical insights into structure and function of arrestins. FEBS J 2021; 288:2529-2549. [DOI: 10.1111/febs.15811] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/26/2021] [Accepted: 03/09/2021] [Indexed: 12/13/2022]
Affiliation(s)
- Yasmin Aydin
- Institute of Biochemistry Faculty of Life Sciences University of Leipzig Germany
| | - Irene Coin
- Institute of Biochemistry Faculty of Life Sciences University of Leipzig Germany
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12
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van Gastel J, Leysen H, Boddaert J, Vangenechten L, Luttrell LM, Martin B, Maudsley S. Aging-related modifications to G protein-coupled receptor signaling diversity. Pharmacol Ther 2020; 223:107793. [PMID: 33316288 DOI: 10.1016/j.pharmthera.2020.107793] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023]
Abstract
Aging is a highly complex molecular process, affecting nearly all tissue systems in humans and is the highest risk factor in developing neurodegenerative disorders such as Alzheimer's and Parkinson's disease, cardiovascular disease and Type 2 diabetes mellitus. The intense complexity of the aging process creates an incentive to develop more specific drugs that attenuate or even reverse some of the features of premature aging. As our current pharmacopeia is dominated by therapeutics that target members of the G protein-coupled receptor (GPCR) superfamily it may be prudent to search for effective anti-aging therapeutics in this fertile domain. Since the first demonstration of GPCR-based β-arrestin signaling, it has become clear that an enhanced appreciation of GPCR signaling diversity may facilitate the creation of therapeutics with selective signaling activities. Such 'biased' ligand signaling profiles can be effectively investigated using both standard molecular biological techniques as well as high-dimensionality data analyses. Through a more nuanced appreciation of the quantitative nature across the multiple dimensions of signaling bias that drugs possess, researchers may be able to further refine the efficacy of GPCR modulators to impact the complex aberrations that constitute the aging process. Identifying novel effector profiles could expand the effective pharmacopeia and assist in the design of precision medicines. This review discusses potential non-G protein effectors, and specifically their potential therapeutic suitability in aging and age-related disorders.
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Affiliation(s)
- Jaana van Gastel
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Hanne Leysen
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Jan Boddaert
- Molecular Pathology Group, Faculty of Medicine and Health Sciences, Laboratory of Cell Biology and Histology, Antwerp, Belgium
| | - Laura Vangenechten
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Louis M Luttrell
- Division of Endocrinology, Diabetes & Medical Genetics, Medical University of South Carolina, USA
| | - Bronwen Martin
- Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Stuart Maudsley
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium.
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13
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Pakharukova N, Masoudi A, Pani B, Staus DP, Lefkowitz RJ. Allosteric activation of proto-oncogene kinase Src by GPCR-beta-arrestin complexes. J Biol Chem 2020; 295:16773-16784. [PMID: 32978252 PMCID: PMC7864071 DOI: 10.1074/jbc.ra120.015400] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/15/2020] [Indexed: 01/14/2023] Open
Abstract
G protein-coupled receptors (GPCRs) initiate signaling cascades via G-proteins and beta-arrestins (βarr). βarr-dependent actions begin with recruitment of βarr to the phosphorylated receptor tail and are followed by engagement with the receptor core. βarrs are known to act as adaptor proteins binding receptors and various effectors, but it is unclear whether in addition to the scaffolding role βarrs can allosterically activate their downstream targets. Here we demonstrate the direct allosteric activation of proto-oncogene kinase Src by GPCR-βarr complexes in vitro and establish the conformational basis of the activation. Whereas free βarr1 had no effect on Src activity, βarr1 in complex with M2 muscarinic or β2-adrenergic receptors reconstituted in lipid nanodiscs activate Src by reducing the lag phase in Src autophosphorylation. Interestingly, receptor-βarr1 complexes formed with a βarr1 mutant, in which the finger-loop, required to interact with the receptor core, has been deleted, fully retain the ability to activate Src. Similarly, βarr1 in complex with only a phosphorylated C-terminal tail of the vasopressin 2 receptor activates Src as efficiently as GPCR-βarr complexes. In contrast, βarr1 and chimeric M2 receptor with nonphosphorylated C-terminal tail failed to activate Src. Taken together, these data demonstrate that the phosphorylated GPCR tail interaction with βarr1 is necessary and sufficient to empower it to allosterically activate Src. Our findings may have implications for understanding more broadly the mechanisms of allosteric activation of downstream targets by βarrs.
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Affiliation(s)
- Natalia Pakharukova
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Ali Masoudi
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Dean P Staus
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, USA; Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina, USA.
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14
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Kraus S, Benard O, Naor Z, Seger R. C-Src is Activated by the EGF Receptor in a Pathway that Mediates JNK and ERK Activation by Gonadotropin-Releasing Hormone in COS7 Cells. Int J Mol Sci 2020; 21:ijms21228575. [PMID: 33202981 PMCID: PMC7697137 DOI: 10.3390/ijms21228575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/08/2020] [Accepted: 11/10/2020] [Indexed: 12/26/2022] Open
Abstract
The key participants in G-protein-coupled receptor (GPCR) signaling are the mitogen-activated protein kinase (MAPK) signaling cascades. The mechanisms involved in the activation of the above cascades by GPCRs are not fully elucidated. The prototypical GPCR is the receptor for gonadotropin-releasing hormone (GnRHR), which serves as a key regulator of the reproductive system. Here, we expressed GnRHR in COS7 cells and found that GnRHR transmits its signals to MAPKs mainly via Gαi and the EGF receptor, without the involvement of Hb-EGF or PKCs. The main pathway that leads to JNK activation downstream of the EGF receptor involves a sequential activation of c-Src and PI3K. ERK activation by GnRHR is mediated by the EGF receptor, which activates Ras either directly or via c-Src. Beside the main pathway, the dissociated Gβγ and β-arrestin may initiate additional (albeit minor) pathways that lead to MAPK activation in the transfected COS7 cells. The pathways detected are significantly different from those in other GnRHR-bearing cells, indicating that GnRH can utilize various signaling mechanisms for MAPK activation. The unique pathway elucidated here, in which c-Src and PI3K are sequentially activated downstream of the EGF receptor, may serve as a prototype of signaling mechanisms by GnRHR and additional GPCRs in various cell types.
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Affiliation(s)
- Sarah Kraus
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 7610001, Israel; (S.K.); (O.B.)
| | - Outhiriaradjou Benard
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 7610001, Israel; (S.K.); (O.B.)
| | - Zvi Naor
- Department of Biochemistry, Tel Aviv University, Ramat Aviv 69978, Israel;
| | - Rony Seger
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 7610001, Israel; (S.K.); (O.B.)
- Correspondence: ; Tel.: +972-8-9343602
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15
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Zhang D, Wang Y, Lin H, Sun Y, Wang M, Jia Y, Yu X, Jiang H, Xu W, Sun JP, Xu Z. Function and therapeutic potential of G protein-coupled receptors in epididymis. Br J Pharmacol 2020; 177:5489-5508. [PMID: 32901914 DOI: 10.1111/bph.15252] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/08/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022] Open
Abstract
Infertility rates for both females and males have increased continuously in recent years. Currently, effective treatments for male infertility with defined mechanisms or targets are still lacking. G protein-coupled receptors (GPCRs) are the largest class of drug targets, but their functions and the implications for the therapeutic development for male infertility largely remain elusive. Nevertheless, recent studies have shown that several members of the GPCR superfamily play crucial roles in the maintenance of ion-water homeostasis of the epididymis, development of the efferent ductules, formation of the blood-epididymal barrier and maturation of sperm. Knowledge of the functions, genetic variations and working mechanisms of such GPCRs, along with the drugs and ligands relevant to their specific functions, provide future directions and a great arsenal for new developments in the treatment of male infertility.
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Affiliation(s)
- Daolai Zhang
- Department of Pharmaceutical Sciences, Binzhou Medical University, Yantai, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yanfei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Hui Lin
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yujing Sun
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Mingwei Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yingli Jia
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University, Beijing, China
| | - Xiao Yu
- Department of Physiology, School of Medicine, Shandong University, Jinan, China
| | - Hui Jiang
- Department of Urology, Peking University Third Hospital, Beijing, China.,Department of Reproductive Medicine Center, Peking University Third Hospital, Beijing, China
| | - Wenming Xu
- Joint Laboratory of Reproductive Medicine, SCU-CUHK, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University West China Second University Hospital, Chengdu, China
| | - Jin-Peng Sun
- Department of Pharmaceutical Sciences, Binzhou Medical University, Yantai, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University, Beijing, China
| | - Zhigang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China.,Shandong Provincial Collaborative Innovation Center of Cell Biology, Shandong Normal University, Jinan, China
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16
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Acharya S, Kundu D, Choi HJ, Kim KM. Metabotropic signaling cascade involved in α4β2 nicotinic acetylcholine receptor-mediated PKCβII activation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118721. [PMID: 32304729 DOI: 10.1016/j.bbamcr.2020.118721] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 04/04/2020] [Accepted: 04/10/2020] [Indexed: 01/27/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) belong to the ionophore receptor family, which regulates plasma membrane conductance to Na+, K+, and Ca2+ ions. Some studies, however, have shown that nAChRs also employ second messengers for intracellular signaling. We previously showed that α4β2 nAChR mediates the translocation of protein kinase CβII (PKCβII) from the cytoplasm to the plasma membrane, which is a typical activation marker for PKCβII. In this study, we investigated the molecular mechanisms underlying PKCβII activation through α4β2 nAChR. α4β2 nAChR is the most abundant nAChR subtype and is implicated in various brain functions and diseases. Putative α4β2 nAChR signaling components were identified by knockdown or chemical inhibition of candidate proteins, and the signaling cascade was deduced by protein interactions in predicted cellular components. α4β2 nAChR-mediated PKCβII translocation was found to occur in an ionophore activity-independent manner. Nicotinic stimulation of α4β2 nAChR activated Src in a β-arrestin1 and 14-3-3η-dependent manner. Activated Src phosphorylated the tyrosine residue(s) on Syk molecules, which in turn interacted with phospholipase C γ1 to trigger the translocation of PKCβII to the cell membrane by elevating cellular diacylglycerol levels. The activated PKCβII in turn exerted a positive feedback effect on Src activation, suggesting that α4β2 nAChR signaling is amplified by a positive feedback loop. These findings provide novel information for unveiling the previously unclear metabotropic second messenger-based signal transduction pathway of nAChRs.
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Affiliation(s)
- Srijan Acharya
- Department of Pharmacology, College of Pharmacy, Chonnam National University, Gwang-Ju 61186, Republic of Korea
| | - Dooti Kundu
- Department of Pharmacology, College of Pharmacy, Chonnam National University, Gwang-Ju 61186, Republic of Korea
| | - Hyun Jin Choi
- College of Pharmacy, Cha University, Seongnam, Gyeonggi-do 13488, Republic of Korea
| | - Kyeong-Man Kim
- Department of Pharmacology, College of Pharmacy, Chonnam National University, Gwang-Ju 61186, Republic of Korea.
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17
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Doodnauth SA, Grinstein S, Maxson ME. Constitutive and stimulated macropinocytosis in macrophages: roles in immunity and in the pathogenesis of atherosclerosis. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180147. [PMID: 30967001 DOI: 10.1098/rstb.2018.0147] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Macrophages respond to several stimuli by forming florid membrane ruffles that lead to fluid uptake by macropinocytosis. This type of induced macropinocytosis, executed by a variety of non-malignant and malignant cells, is initiated by transmembrane receptors and is involved in nutrient acquisition and mTOR signalling. However, macrophages also perform a unique type of constitutive ruffling and macropinocytosis that is dependent on the presence of extracellular calcium. Calcium-sensing receptors are responsible for this activity. This distinct form of macropinocytosis enables macrophages to continuously sample their microenvironment for antigenic molecules and for pathogen- and danger-associated molecular patterns, as part of their immune surveillance functions. Interestingly, even within the monocyte lineage, there are differences in macropinocytic ability that reflect the polarized functional roles of distinct macrophage subsets. This review discusses the shared and distinct features of both induced and constitutive macropinocytosis displayed by the macrophage lineage and their roles in physiology, immunity and pathophysiology. In particular, we analyse the role of macropinocytosis in the uptake of modified low-density lipoprotein (LDL) and its contribution to foam cell and atherosclerotic plaque formation. We propose a combined role of scavenger receptors and constitutive macropinocytosis in oxidized LDL uptake, a process we have termed 'receptor-assisted macropinocytosis'. This article is part of the Theo Murphy meeting issue 'Macropinocytosis'.
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Affiliation(s)
- Sasha A Doodnauth
- 1 Princess Margaret Cancer Center, University Health Network , Toronto, ON , Canada M5G 1L7.,2 Department of Medical Biophysics, University of Toronto , Toronto, ON , Canada M5G 1L7
| | - Sergio Grinstein
- 3 Program in Cell Biology, Hospital for Sick Children , 686 Bay Street, Toronto, ON , Canada M5G 0A4.,4 Department of Biochemistry, University of Toronto , 1 King's Circle, Toronto, ON , Canada M5S 1A8.,5 Keenan Research Centre of the Li Ka Shing Knowledge Institute , St. Michael's Hospital, 290 Victoria Street, Toronto, ON , Canada M5C 1N8
| | - Michelle E Maxson
- 3 Program in Cell Biology, Hospital for Sick Children , 686 Bay Street, Toronto, ON , Canada M5G 0A4
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18
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Muscarinic receptor stimulation induces TASK1 channel endocytosis through a PKC-Pyk2-Src pathway in PC12 cells. Cell Signal 2020; 65:109434. [DOI: 10.1016/j.cellsig.2019.109434] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/01/2019] [Accepted: 10/01/2019] [Indexed: 11/21/2022]
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19
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Iida M, Sahashi K, Kondo N, Nakatsuji H, Tohnai G, Tsutsumi Y, Noda S, Murakami A, Onodera K, Okada Y, Nakatochi M, Tsukagoshi Okabe Y, Shimizu S, Mizuno M, Adachi H, Okano H, Sobue G, Katsuno M. Src inhibition attenuates polyglutamine-mediated neuromuscular degeneration in spinal and bulbar muscular atrophy. Nat Commun 2019; 10:4262. [PMID: 31537808 PMCID: PMC6753158 DOI: 10.1038/s41467-019-12282-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 08/29/2019] [Indexed: 12/12/2022] Open
Abstract
Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular disease caused by an expanded CAG repeat in the androgen receptor (AR) gene. Here, we perform a comprehensive analysis of signaling pathways in a mouse model of SBMA (AR-97Q mice) utilizing a phosphoprotein assay. We measure the levels of 17 phosphorylated proteins in spinal cord and skeletal muscle of AR-97Q mice at three stages. The level of phosphorylated Src (p-Src) is markedly increased in the spinal cords and skeletal muscles of AR-97Q mice prior to the onset. Intraperitoneal administration of a Src kinase inhibitor improves the behavioral and histopathological phenotypes of the transgenic mice. We identify p130Cas as an effector molecule of Src and show that the phosphorylated p130Cas is elevated in murine and cellular models of SBMA. These results suggest that Src kinase inhibition is a potential therapy for SBMA.
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Affiliation(s)
- Madoka Iida
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
- Japan Society for the Promotion of Science, 5-3-1, Kojimachi, Chiyoda-ku, Tokyo, 102-0083, Japan
| | - Kentaro Sahashi
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Naohide Kondo
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Hideaki Nakatsuji
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Genki Tohnai
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Yutaka Tsutsumi
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Seiya Noda
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
- Department of Neurology, National Hospital Organization Suzuka National Hospital, 3-2-1, Kasado, Suzuka city, Mie, 513-8501, Japan
| | - Ayuka Murakami
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
- Department of Neurology, National Hospital Organization Suzuka National Hospital, 3-2-1, Kasado, Suzuka city, Mie, 513-8501, Japan
| | - Kazunari Onodera
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
- Department of Neurology, Aichi Medical University School of Medicine, 1, Karimata, Yazako, Nagakute-city, Aichi, 480-1195, Japan
| | - Yohei Okada
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
- Department of Neurology, Aichi Medical University School of Medicine, 1, Karimata, Yazako, Nagakute-city, Aichi, 480-1195, Japan
- Department of Physiology, Keio University School of Medicine, 35, Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Masahiro Nakatochi
- Department of Nursing, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya city, Aichi, 461-8673, Japan
| | - Yuka Tsukagoshi Okabe
- Department of Advanced Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8560, Japan
| | - Shinobu Shimizu
- Department of Advanced Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8560, Japan
| | - Masaaki Mizuno
- Department of Advanced Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8560, Japan
| | - Hiroaki Adachi
- Department of Neurology, University of Occupational and Environmental Health School of Medicine, 1-1, Iseigaoka, Yahatanichi-ku, Kitakyushu-city, Fukuoka, 807-0804, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35, Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Gen Sobue
- Brain and Mind Research Center, Nagoya University, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan
| | - Masahisa Katsuno
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya city, Aichi, 466-8550, Japan.
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20
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Tsai CC, Kuo FT, Lee SB, Chang YT, Fu HW. Endocytosis-dependent lysosomal degradation of Src induced by protease-activated receptor 1. FEBS Lett 2019; 593:504-517. [PMID: 30758841 DOI: 10.1002/1873-3468.13336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/28/2019] [Accepted: 02/07/2019] [Indexed: 11/08/2022]
Abstract
Src plays a critical role in regulating cellular responses induced by protease-activated receptor 1 (PAR1). Here, we found that PAR1 activation induces lysosomal degradation of Src. Src is associated and trafficked together with activated PAR1 to early endosomes and then sorted to lysosomes for degradation. Blocking agonist-induced endocytosis of PAR1 by inhibition of dynamin activity suppresses PAR1-induced degradation of Src. However, Src activity is neither required for agonist-induced PAR1 internalization nor required for Src degradation upon PAR1 activation. We show that PAR1 activation triggers endocytosis-dependent lysosomal degradation of Src in both human embryonic kidney 293 and human umbilical vein endothelial cells. Our finding provides a new paradigm for how an irreversibly activated receptor regulates its downstream signalling.
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Affiliation(s)
- Chung-Che Tsai
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Fang-Ting Kuo
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Sung-Bau Lee
- Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.,College of Pharmacy, Taipei Medical University, Taiwan, Republic of China
| | - Yu-Ting Chang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Hua-Wen Fu
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.,Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
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21
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Laporte SA, Scott MGH. β-Arrestins: Multitask Scaffolds Orchestrating the Where and When in Cell Signalling. Methods Mol Biol 2019; 1957:9-55. [PMID: 30919345 DOI: 10.1007/978-1-4939-9158-7_2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The β-arrestins (β-arrs) were initially appreciated for the roles they play in the desensitization and endocytosis of G protein-coupled receptors (GPCRs). They are now also known to act as multifunctional adaptor proteins binding many non-receptor protein partners to control multiple signalling pathways. β-arrs therefore act as key regulatory hubs at the crossroads of external cell inputs and functional outputs in cellular processes ranging from gene transcription to cell growth, survival, cytoskeletal regulation, polarity, and migration. An increasing number of studies have also highlighted the scaffolding roles β-arrs play in vivo in both physiological and pathological conditions, which opens up therapeutic avenues to explore. In this introductory review chapter, we discuss the functional roles that β-arrs exert to control GPCR function, their dynamic scaffolding roles and how this impacts signal transduction events, compartmentalization of β-arrs, how β-arrs are regulated themselves, and how the combination of these events culminates in cellular regulation.
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Affiliation(s)
- Stéphane A Laporte
- Department of Medicine, Research Institute of the McGill University Health Center (RI-MUHC), McGill University, Montreal, QC, Canada. .,Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada. .,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, Canada. .,RI-MUHC/Glen Site, Montréal, QC, Canada.
| | - Mark G H Scott
- Institut Cochin, INSERM U1016, Paris, France. .,CNRS, UMR 8104, Paris, France. .,Univ. Paris Descartes, Sorbonne Paris Cité, Paris, France.
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22
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Yang F, Xiao P, Qu CX, Liu Q, Wang LY, Liu ZX, He QT, Liu C, Xu JY, Li RR, Li MJ, Li Q, Guo XZ, Yang ZY, He DF, Yi F, Ruan K, Shen YM, Yu X, Sun JP, Wang J. Allosteric mechanisms underlie GPCR signaling to SH3-domain proteins through arrestin. Nat Chem Biol 2018; 14:876-886. [PMID: 30120361 DOI: 10.1038/s41589-018-0115-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 07/03/2018] [Indexed: 12/30/2022]
Abstract
Signals from 800 G-protein-coupled receptors (GPCRs) to many SH3 domain-containing proteins (SH3-CPs) regulate important physiological functions. These GPCRs may share a common pathway by signaling to SH3-CPs via agonist-dependent arrestin recruitment rather than through direct interactions. In the present study, 19F-NMR and cellular studies revealed that downstream of GPCR activation engagement of the receptor-phospho-tail with arrestin allosterically regulates the specific conformational states and functional outcomes of remote β-arrestin 1 proline regions (PRs). The observed NMR chemical shifts of arrestin PRs were consistent with the intrinsic efficacy and specificity of SH3 domain recruitment, which was controlled by defined propagation pathways. Moreover, in vitro reconstitution experiments and biophysical results showed that the receptor-arrestin complex promoted SRC kinase activity through an allosteric mechanism. Thus, allosteric regulation of the conformational states of β-arrestin 1 PRs by GPCRs and the allosteric activation of downstream effectors by arrestin are two important mechanisms underlying GPCR-to-SH3-CP signaling.
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Affiliation(s)
- Fan Yang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China.,Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang district, Beijing, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Shandong, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Peng Xiao
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China.,Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Science, Shandong University, Jinan, Shandong, China
| | - Chang-Xiu Qu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Qi Liu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China.,Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang district, Beijing, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Shandong, China
| | - Liu-Yang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, USA
| | - Zhi-Xin Liu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Qing-Tao He
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Chuan Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Jian-Ye Xu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Rui-Rui Li
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Meng-Jing Li
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Qing Li
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Shandong, China
| | - Xu-Zhen Guo
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang district, Beijing, China
| | - Zhao-Ya Yang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Dong-Fang He
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China
| | - Fan Yi
- Department of Pharmacology, Shandong University School of Medicine, Jinan, China
| | - Ke Ruan
- Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei Anhui, China
| | - Yue-Mao Shen
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, USA
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, Shandong University School of Medicine, Shandong, China
| | - Jin-Peng Sun
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China. .,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China.
| | - Jiangyun Wang
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang district, Beijing, China.
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23
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Peterson YK, Luttrell LM. The Diverse Roles of Arrestin Scaffolds in G Protein-Coupled Receptor Signaling. Pharmacol Rev 2017. [PMID: 28626043 DOI: 10.1124/pr.116.013367] [Citation(s) in RCA: 299] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The visual/β-arrestins, a small family of proteins originally described for their role in the desensitization and intracellular trafficking of G protein-coupled receptors (GPCRs), have emerged as key regulators of multiple signaling pathways. Evolutionarily related to a larger group of regulatory scaffolds that share a common arrestin fold, the visual/β-arrestins acquired the capacity to detect and bind activated GPCRs on the plasma membrane, which enables them to control GPCR desensitization, internalization, and intracellular trafficking. By acting as scaffolds that bind key pathway intermediates, visual/β-arrestins both influence the tonic level of pathway activity in cells and, in some cases, serve as ligand-regulated scaffolds for GPCR-mediated signaling. Growing evidence supports the physiologic and pathophysiologic roles of arrestins and underscores their potential as therapeutic targets. Circumventing arrestin-dependent GPCR desensitization may alleviate the problem of tachyphylaxis to drugs that target GPCRs, and find application in the management of chronic pain, asthma, and psychiatric illness. As signaling scaffolds, arrestins are also central regulators of pathways controlling cell growth, migration, and survival, suggesting that manipulating their scaffolding functions may be beneficial in inflammatory diseases, fibrosis, and cancer. In this review we examine the structure-function relationships that enable arrestins to perform their diverse roles, addressing arrestin structure at the molecular level, the relationship between arrestin conformation and function, and sites of interaction between arrestins, GPCRs, and nonreceptor-binding partners. We conclude with a discussion of arrestins as therapeutic targets and the settings in which manipulating arrestin function might be of clinical benefit.
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Affiliation(s)
- Yuri K Peterson
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy (Y.K.P.), and Departments of Medicine and Biochemistry and Molecular Biology (L.M.L.), Medical University of South Carolina, Charleston, South Carolina; and Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina (L.M.L.)
| | - Louis M Luttrell
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy (Y.K.P.), and Departments of Medicine and Biochemistry and Molecular Biology (L.M.L.), Medical University of South Carolina, Charleston, South Carolina; and Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina (L.M.L.)
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24
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Ghosh E, Srivastava A, Baidya M, Kumari P, Dwivedi H, Nidhi K, Ranjan R, Dogra S, Koide A, Yadav PN, Sidhu SS, Koide S, Shukla AK. A synthetic intrabody-based selective and generic inhibitor of GPCR endocytosis. NATURE NANOTECHNOLOGY 2017; 12:1190-1198. [PMID: 28967893 PMCID: PMC5722207 DOI: 10.1038/nnano.2017.188] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 08/13/2017] [Indexed: 05/06/2023]
Abstract
Beta-arrestins (βarrs) critically mediate desensitization, endocytosis and signalling of G protein-coupled receptors (GPCRs), and they scaffold a large number of interaction partners. However, allosteric modulation of their scaffolding abilities and direct targeting of their interaction interfaces to modulate GPCR functions selectively have not been fully explored yet. Here we identified a series of synthetic antibody fragments (Fabs) against different conformations of βarrs from phage display libraries. Several of these Fabs allosterically and selectively modulated the interaction of βarrs with clathrin and ERK MAP kinase. Interestingly, one of these Fabs selectively disrupted βarr-clathrin interaction, and when expressed as an intrabody, it robustly inhibited agonist-induced endocytosis of a broad set of GPCRs without affecting ERK MAP kinase activation. Our data therefore demonstrate the feasibility of selectively targeting βarr interactions using intrabodies and provide a novel framework for fine-tuning GPCR functions with potential therapeutic implications.
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Affiliation(s)
- Eshan Ghosh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Ashish Srivastava
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Mithu Baidya
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Punita Kumari
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Hemlata Dwivedi
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Kumari Nidhi
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Ravi Ranjan
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Shalini Dogra
- CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Akiko Koide
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York 10016, USA
- Department of Medicine, New York University School of Medicine, New York 10016, USA
| | - Prem N Yadav
- CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Sachdev S Sidhu
- Department of Molecular Genetics, University of Toronto, Ontario MSS1A8, Canada
| | - Shohei Koide
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York 10016, USA
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York 10016, USA
| | - Arun K Shukla
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
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25
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Tompkins JD, Clason TA, Buttolph TR, Girard BM, Linden AK, Hardwick JC, Merriam LA, May V, Parsons RL. Src family kinase inhibitors blunt PACAP-induced PAC1 receptor endocytosis, phosphorylation of ERK, and the increase in cardiac neuron excitability. Am J Physiol Cell Physiol 2017; 314:C233-C241. [PMID: 29141923 DOI: 10.1152/ajpcell.00223.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pituitary adenylate cyclase activating polypeptide (PACAP, Adcyap1) activation of PAC1 receptors ( Adcyap1r1) significantly increases excitability of guinea pig cardiac neurons. This modulation of excitability is mediated in part by plasma membrane G protein-dependent activation of adenylyl cyclase and downstream signaling cascades. However, additional mechanisms responsible for the enhanced excitability are activated following internalization of the PAC1 receptor and endosomal signaling. Src family kinases play critical roles mediating endocytosis of many trophic factor and G protein-coupled receptors. The present study investigated whether Src family kinases also support the PACAP-induced PAC1 receptor internalization, phosphorylation of ERK, and enhanced neuronal excitability. Using human embryonic kidney cells stably expressing a green fluorescent protein-tagged PAC1 receptor, treatment with the Src family kinase inhibitor PP2 (10 µM) markedly reduced the PACAP-induced PAC1 receptor internalization, and in parallel, both PP2 and Src inhibitor 1 (Src-1, 2 µM) reduced ERK activation determined by Western blot analysis. In contrast, Src family kinase inhibitors did not eliminate a PACAP-induced rise in global calcium generated by inositol (1,4,5)-trisphosphate-induced release of calcium from endoplasmic reticulum stores. From confocal analysis of phosphorylated ERK immunostaining, PP2 treatment significantly attenuated PACAP activation of ERK in neurons within cardiac ganglia whole mount preparations. Intracellular recordings demonstrated that PP2 also significantly blunted a PACAP-induced increase in cardiac neuron excitability. These studies demonstrate Src-related kinase activity in PAC1 receptor internalization, activation of MEK/ERK signaling, and regulation of neuronal excitability. The present results provide further support for the importance of PAC1 receptor endosomal signaling as a key mechanism regulating cellular function.
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Affiliation(s)
- John D Tompkins
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California , Los Angeles, California
| | - Todd A Clason
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | - Thomas R Buttolph
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | - Beatrice M Girard
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | - Anne K Linden
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | | | - Laura A Merriam
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | - Victor May
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
| | - Rodney L Parsons
- Department of Neurological Sciences, Robert Larner MD College of Medicine, University of Vermont , Burlington, Vermont
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26
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Srivastava K, Pickard A, McDade S, McCance DJ. p63 drives invasion in keratinocytes expressing HPV16 E6/E7 genes through regulation of Src-FAK signalling. Oncotarget 2017; 8:16202-16219. [PMID: 26001294 PMCID: PMC5369957 DOI: 10.18632/oncotarget.3892] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 04/24/2015] [Indexed: 02/07/2023] Open
Abstract
Using microarray information from oro-pharyngeal data sets and results from primary human foreskin keratinocytes (HFK) expressing Human Papilloma Virus (HPV)-16 E6/E7 proteins, we show that p63 expression regulates signalling molecules which initiate cell migration such as Src and focal adhesion kinase (FAK) and induce invasion in 3D-organotypic rafts; a phenotype that can be reversed by depletion of p63. Knockdown of Src or FAK in the invasive cells restored focal adhesion protein paxillin at cell periphery and impaired the cell migration. In addition, specific inhibition of FAK (PF573228) or Src (dasatinib) activities mitigated invasion and attenuated the expression/activity of matrix metalloproteinase 14 (MMP14), a pivotal MMP in the MMP activation cascade. Expression of constitutively active Src in non-invasive HFK expressing E6/E7 proteins upregulated the activity of c-Jun and MMP14, and induced invasion in rafts. Depletion of Src, FAK or AKT in the invasive cells normalised the expression/activity of c-Jun and MMP14, thus implicating the Src-FAK/AKT/AP-1 signalling in MMP14-mediated extra-cellular matrix remodelling. Up-regulation of Src, AP-1, MMP14 and p63 expression was confirmed in oro-pharyngeal cancer. Since p63 transcriptionally regulated expression of many of the genes in this signalling pathway, it suggests that it has a central role in cancer progression.
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Affiliation(s)
- Kirtiman Srivastava
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Adam Pickard
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Simon McDade
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Dennis J McCance
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast BT9 7BL, UK.,Department of Pathology, School of Medicine, University of New Mexico, Albuquerque, NM 87131-0001, USA
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27
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Bourquard T, Landomiel F, Reiter E, Crépieux P, Ritchie DW, Azé J, Poupon A. Unraveling the molecular architecture of a G protein-coupled receptor/β-arrestin/Erk module complex. Sci Rep 2015; 5:10760. [PMID: 26030356 PMCID: PMC4649906 DOI: 10.1038/srep10760] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/26/2015] [Indexed: 12/22/2022] Open
Abstract
β-arrestins serve as signaling scaffolds downstream of G protein-coupled receptors, and thus play a crucial role in a plethora of cellular processes. Although it is largely accepted that the ability of β-arrestins to interact simultaneously with many protein partners is key in G protein-independent signaling of GPCRs, only the precise knowledge of these multimeric arrangements will allow a full understanding of the dynamics of these interactions and their functional consequences. However, current experimental procedures for the determination of the three-dimensional structures of protein-protein complexes are not well adapted to analyze these short-lived, multi-component assemblies. We propose a model of the receptor/β-arrestin/Erk1 signaling module, which is consistent with most of the available experimental data. Moreover, for the β-arrestin/Raf1 and the β-arrestin/ERK interactions, we have used the model to design interfering peptides and shown that they compete with both partners, hereby demonstrating the validity of the predicted interaction regions.
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Affiliation(s)
- Thomas Bourquard
- 1] BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France; CNRS, UMR7247, F-37380 Nouzilly, France; Université François Rabelais, 37041 Tours, France; IFCE, Nouzilly, F-37380 France [2] INRIA Nancy, 615 Rue du Jardin Botanique, Villers-lès-Nancy, 54600 France
| | - Flavie Landomiel
- BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France; CNRS, UMR7247, F-37380 Nouzilly, France; Université François Rabelais, 37041 Tours, France; IFCE, Nouzilly, F-37380 France
| | - Eric Reiter
- BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France; CNRS, UMR7247, F-37380 Nouzilly, France; Université François Rabelais, 37041 Tours, France; IFCE, Nouzilly, F-37380 France
| | - Pascale Crépieux
- BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France; CNRS, UMR7247, F-37380 Nouzilly, France; Université François Rabelais, 37041 Tours, France; IFCE, Nouzilly, F-37380 France
| | - David W Ritchie
- INRIA Nancy, 615 Rue du Jardin Botanique, Villers-lès-Nancy, 54600 France
| | - Jérôme Azé
- Bioinformatics group - AMIB INRIA - Laboratoire de Recherche en Informatique, Université Paris-Sud, Orsay, 91405 France
| | - Anne Poupon
- BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France; CNRS, UMR7247, F-37380 Nouzilly, France; Université François Rabelais, 37041 Tours, France; IFCE, Nouzilly, F-37380 France
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28
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Wang S, Gong H, Jiang G, Ye Y, Wu J, You J, Zhang G, Sun A, Komuro I, Ge J, Zou Y. Src is required for mechanical stretch-induced cardiomyocyte hypertrophy through angiotensin II type 1 receptor-dependent β-arrestin2 pathways. PLoS One 2014; 9:e92926. [PMID: 24699426 PMCID: PMC3974699 DOI: 10.1371/journal.pone.0092926] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 02/26/2014] [Indexed: 01/14/2023] Open
Abstract
Angiotensin II (AngII) type 1 receptor (AT1-R) can be activated by mechanical stress (MS) without the involvement of AngII during the development of cardiomyocyte hypertrophy, in which G protein-independent pathways are critically involved. Although β-arrestin2-biased signaling has been speculated, little is known about how AT1-R/β-arrestin2 leads to ERK1/2 activation. Here, we present a novel mechanism by which Src kinase mediates AT1-R/β-arrestin2-dependent ERK1/2 phosphorylation in response to MS. Differing from stimulation by AngII, MS-triggered ERK1/2 phosphorylation is neither suppressed by overexpression of RGS4 (the negative regulator of the G-protein coupling signal) nor by inhibition of Gαq downstream protein kinase C (PKC) with GF109203X. The release of inositol 1,4,5-triphosphate (IP3) is increased by AngII but not by MS. These results collectively suggest that MS-induced ERK1/2 activation through AT1-R might be independent of G-protein coupling. Moreover, either knockdown of β-arrestin2 or overexpression of a dominant negative mutant of β-arrestin2 prevents MS-induced activation of ERK1/2. We further identifies a relationship between Src, a non-receptor tyrosine kinase and β-arrestin2 using analyses of co-immunoprecipitation and immunofluorescence after MS stimulation. Furthermore, MS-, but not AngII-induced ERK1/2 phosphorylation is attenuated by Src inhibition, which also significantly improves pressure overload-induced cardiac hypertrophy and dysfunction in mice lacking AngII. Finally, MS-induced Src activation and hypertrophic response are abolished by candesartan but not by valsartan whereas AngII-induced responses can be abrogated by both blockers. Our results suggest that Src plays a critical role in MS-induced cardiomyocyte hypertrophy through β-arrestin2-associated angiotensin II type 1 receptor signaling.
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MESH Headings
- Angiotensinogen/physiology
- Animals
- Animals, Newborn
- Arrestins/genetics
- Arrestins/metabolism
- Blotting, Western
- Cardiomegaly/metabolism
- Cardiomegaly/pathology
- Cells, Cultured
- Echocardiography
- Immunoenzyme Techniques
- Immunoprecipitation
- Inositol 1,4,5-Trisphosphate/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mitogen-Activated Protein Kinase 1/genetics
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3/genetics
- Mitogen-Activated Protein Kinase 3/metabolism
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Phosphorylation
- RNA, Messenger/genetics
- Rats
- Real-Time Polymerase Chain Reaction
- Receptor, Angiotensin, Type 1/genetics
- Receptor, Angiotensin, Type 1/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction
- Stress, Mechanical
- beta-Arrestins
- src-Family Kinases/genetics
- src-Family Kinases/metabolism
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Affiliation(s)
- Shijun Wang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Hui Gong
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Guoliang Jiang
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Yong Ye
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Jian Wu
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Jieyun You
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Guoping Zhang
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Aijun Sun
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Issei Komuro
- Department of Cardiovascular Medicine, the University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Junbo Ge
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Yunzeng Zou
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
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29
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Soung YH, Pruitt K, Chung J. Epigenetic silencing of ARRDC3 expression in basal-like breast cancer cells. Sci Rep 2014; 4:3846. [PMID: 24457910 PMCID: PMC3900932 DOI: 10.1038/srep03846] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 12/27/2013] [Indexed: 12/13/2022] Open
Abstract
Arrestin domain-containing 3 (ARRDC3) is a tumor suppressor whose expression is either lost or suppressed in basal-like breast cancer (BLBC). However, the mechanism by which BLBC suppresses ARRDC3 expression is not established. Here, we show that expression of ARRDC3 in BLBC cells is suppressed at the transcriptional level. Suppression of ARRDC3 expression in BLBC cells involves epigenetic silencing as inhibitors of class III histone deacetylases (HDACs) significantly restores ARRDC3 levels in BLBC cells. SIRT2, among class III HDACs, plays a major role in epigenetic silencing of ARRDC3 in MDA-MB-231 cells. Acetylation levels of the ARRDC3 promoter in BLBC cells is significantly lower than that of other sub-types of BC cells. Chromatin immunopreciptitation analysis established SIRT2 binding at ARRDC3 promoter in BLBC cells. Our studies indicate that SIRT2 dependent epigenetic silencing of ARRDC3 is one of the important events that may contribute to the aggressive nature of BLBC cells.
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Affiliation(s)
- Young Hwa Soung
- Department of Physiology and Stephenson cancer center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Kevin Pruitt
- Department of Molecular and Cellular Physiology Louisiana State University Health Science Center Shreveport, Louisiana 71130
| | - Jun Chung
- Department of Physiology and Stephenson cancer center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
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30
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Abstract
The four members of the mammalian arrestin family, two visual and two nonvisual, share the property of stimulus-dependent docking to G protein-coupled receptors. This conformational selectivity permits them to function in receptor desensitization, as arrestin binding sterically inhibits G protein coupling. The two nonvisual arrestins further act as adapter proteins, linking receptors to the clathrin-dependent endocytic machinery and regulating receptor sequestration, intracellular trafficking, recycling, and degradation. Arrestins also function as ligand-regulated scaffolds, recruiting catalytically active proteins into receptor-based multiprotein "signalsome" complexes. Arrestin binding thus marks the transition from a transient G protein-coupled state on the plasma membrane to a persistent arrestin-coupled state that continues to signal as the receptor internalizes. Two of the earliest discovered and most studied arrestin-dependent signaling pathways involve regulation of Src family nonreceptor tyrosine kinases and the ERK1/2 mitogen-activated kinase cascade. In each case, arrestin scaffolding imposes constraints on kinase activity that dictate signal duration and substrate specificity. Evidence suggests that arrestin-bound ERK1/2 and Src not only play regulatory roles in receptor desensitization and trafficking but also mediate longer term effects on cell growth, migration, proliferation, and survival.
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Affiliation(s)
- Erik G Strungs
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
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31
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Baudry M, Bi X, Aguirre C. Progesterone-estrogen interactions in synaptic plasticity and neuroprotection. Neuroscience 2013; 239:280-94. [PMID: 23142339 PMCID: PMC3628409 DOI: 10.1016/j.neuroscience.2012.10.051] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 10/23/2012] [Accepted: 10/26/2012] [Indexed: 01/01/2023]
Abstract
17ß-Estradiol and progesterone exert a number of physiological effects throughout the brain due to interactions with several types of receptors belonging to the traditional family of intracellular hormonal receptors as well as to membrane-bound receptors. In particular, both hormones elicit rapid modifications of neuronal excitability that have been postulated to underlie their effects on synaptic plasticity and learning and memory. Likewise, both hormones have been shown to be neuroprotective under certain conditions, possibly due to the activation of pro-survival pathways and the inhibition of pro-apoptotic cascades. Because of the similarities in their cellular effects, there have been a number of questions raised by numerous observations that progesterone inhibits the effects of estrogen. In this manuscript, we first review the interactions between 17ß-estradiol (E2) and progesterone (P4) in synaptic plasticity, and conclude that, while E2 exerts a clear and important role in long-term potentiation of synaptic transmission in hippocampal neurons, the role of P4 is much less clear, and could be accounted by the direct or indirect regulation of GABAA receptors. We then discuss the neuroprotective roles of both hormones, in particular against excitotoxicity. In this case, the neuroprotective effects of these hormones are very similar to those of the neurotrophic factor BDNF. Interestingly, P4 antagonizes the effects of E2, possibly through the regulation of estrogen receptors or of proteins associated with the receptors or interactions with signaling pathways activated by E2. Overall, this review emphasizes the existence of common molecules and pathways that participate in the regulation of both synaptic plasticity and neurodegeneration.
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Affiliation(s)
- M Baudry
- GCBS and COMP, Western University of Health Sciences, Pomona, CA, USA.
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32
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Ahn KH, Mahmoud MM, Shim JY, Kendall DA. Distinct roles of β-arrestin 1 and β-arrestin 2 in ORG27569-induced biased signaling and internalization of the cannabinoid receptor 1 (CB1). J Biol Chem 2013; 288:9790-9800. [PMID: 23449980 PMCID: PMC3617280 DOI: 10.1074/jbc.m112.438804] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 02/19/2013] [Indexed: 12/14/2022] Open
Abstract
The cannabinoid receptor 1 (CB1) is a G protein-coupled receptor primarily expressed in brain tissue that has been implicated in several disease states. CB1 allosteric compounds, such as ORG27569, offer enormous potential as drugs over orthosteric ligands, but their mechanistic, structural, and downstream effects upon receptor binding have not been established. Previously, we showed that ORG27569 enhances agonist binding affinity to CB1 but inhibits G protein-dependent agonist signaling efficacy in HEK293 cells and rat brain expressing the CB1 receptor (Ahn, K. H., Mahmoud, M. M., and Kendall, D. A. (2012) J. Biol. Chem. 287, 12070-12082). Here, we identify the mediators of CB1 receptor internalization and ORG27569-induced G protein-independent signaling. Using siRNA technology, we elucidate an ORG27569-induced signaling mechanism for CB1 wherein β-arrestin 1 mediates short term signaling to ERK1/2 with a peak at 5 min and other upstream kinase components including MEK1/2 and c-Src. Consistent with these findings, we demonstrate co-localization of CB1-GFP with red fluorescent protein-β-arrestin 1 upon ORG27569 treatment using confocal microscopy. In contrast, we show the critical role of β-arrestin 2 in CB1 receptor internalization upon treatment with CP55940 (agonist) or treatment with ORG27569. These results demonstrate for the first time the involvement of β-arrestin in CB1-biased signaling by a CB1 allosteric modulator and also define the differential role of the two β-arrestin isoforms in CB1 signaling and internalization.
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Affiliation(s)
- Kwang H Ahn
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269
| | - Mariam M Mahmoud
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut 06269
| | - Joong-Youn Shim
- J. L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina 27707
| | - Debra A Kendall
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269.
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Lin A, DeFea KA. β-Arrestin-kinase scaffolds: turn them on or turn them off? WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2013; 5:231-41. [PMID: 23319470 DOI: 10.1002/wsbm.1203] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
G-protein-coupled receptors (GPCRs) can signal through heterotrimeric G-proteins or through β-arrestins to elicit responses to a plethora of extracellular stimuli. While the mechanisms underlying G-protein signaling is relatively well understood, the mechanisms by which β-arrestins regulate the diverse set of proteins with which they associate remain unclear. Multi-protein complexes are a common feature of β-arrestin-dependent signaling. The first two such complexes discovered were the mitogen-activated kinases modules associated with extracellular regulated kinases (ERK1/2) and Jnk3. Subsequently a number of other kinases have been shown to undergo β-arrestin-dependent regulation, including Akt, phosphatidylinositol-3kinase (PI3K), Lim-domain-containing kinase (LIMK), calcium calmodulin kinase II (CAMKII), and calcium calmodulin kinase kinase β (CAMKKβ). Some are positively and some negatively regulated by β-arrestin association. One of the missing links to understanding these pathways is the molecular mechanisms by which the activity of these kinases is regulated. Do β-arrestins merely serve as scaffolds to bring enzyme and substrate together or do they have a direct effect on the enzymatic activities of target kinases? Recent evidence suggests that both mechanisms are involved and that the mechanisms by which β-arrestins regulate kinase activity varies with the target kinase. This review discusses recent advances in the field focusing on 5 kinases for which considerable mechanistic detail and specific sites of interaction have been elucidated.
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Affiliation(s)
- Alice Lin
- Department of Biomedical Sciences, University of California Riverside, Riverside, CA, USA
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Arrestins as regulators of kinases and phosphatases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:115-47. [PMID: 23764052 DOI: 10.1016/b978-0-12-394440-5.00005-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The discovery that, in addition to mediating G protein-coupled receptor (GPCR) desensitization and endocytosis, arrestins bind to diverse catalytically active nonreceptor proteins and act as ligand-regulated signaling scaffolds led to a paradigm shift in the study of GPCR signal transduction. Research over the past decade has solidified the concept that arrestins confer novel GPCR-signaling capacity by recruiting protein and lipid kinase, phosphatase, phosphodiesterase, and ubiquitin ligase activity into receptor-based multiprotein "signalsome" complexes. Signalsomes regulate downstream pathways controlled by Src family nonreceptor tyrosine kinases, mitogen-activated protein kinases, protein kinase B (AKT), glycogen synthase kinase 3, protein phosphatase 2A, nuclear factor-κB, and several others, imposing spatial and temporal control on their function. While many arrestin-bound kinases and phosphatases are involved in the control of cytoskeletal rearrangement, vesicle endocytosis, exocytosis, and cell migration, other signals reach into the nucleus, affecting cell proliferation, apoptosis, and survival. Indeed, the kinase/phosphatase network regulated by arrestins may be fully as diverse as that regulated by heterotrimeric G proteins.
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35
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Molecular Mechanisms of G Protein-Independent Signaling Mediated by 7-Transmembrane Receptors. NEUROPHYSIOLOGY+ 2012. [DOI: 10.1007/s11062-012-9295-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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36
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Law IKM, Murphy JE, Bakirtzi K, Bunnett NW, Pothoulakis C. Neurotensin-induced proinflammatory signaling in human colonocytes is regulated by β-arrestins and endothelin-converting enzyme-1-dependent endocytosis and resensitization of neurotensin receptor 1. J Biol Chem 2012; 287:15066-75. [PMID: 22416137 DOI: 10.1074/jbc.m111.327262] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The neuropeptide/hormone neurotensin (NT) mediates intestinal inflammation and cell proliferation by binding of its high affinity receptor, neurotensin receptor-1 (NTR1). NT stimulates IL-8 expression in NCM460 human colonic epithelial cells by both MAP kinase- and NF-κB-dependent pathways. Although the mechanism of NTR1 endocytosis has been studied, the relationship between NTR1 intracellular trafficking and inflammatory signaling remains to be elucidated. In the present study, we show that in NCM460 cells exposed to NT, β-arrestin-1 (βARR1), and β-arrestin-2 (βARR2) translocate to early endosomes together with NTR1. Endothelin-converting enzyme-1 (ECE-1) degrades NT in acidic conditions, and its activity is crucial for NTR1 recycling. Pretreatment of NCM460 cells with the ECE-1 inhibitor SM19712 or gene silencing of βARR1 or βARR2 inhibits NT-stimulated ERK1/2 and JNK phosphorylation, NF-κB p65 nuclear translocation and phosphorylation, and IL-8 secretion. Furthermore, NT-induced cell proliferation, but not IL-8 transcription, is attenuated by the JNK inhibitor, JNK(AII). Thus, NTR1 internalization and recycling in human colonic epithelial cells involves βARRs and ECE-1, respectively. Our results also indicate that βARRs and ECE-1-dependent recycling regulate MAP kinase and NF-κB signaling as well as cell proliferation in human colonocytes in response to NT.
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Affiliation(s)
- Ivy Ka Man Law
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90095-7019, USA
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Hoeppner CZ, Cheng N, Ye RD. Identification of a nuclear localization sequence in β-arrestin-1 and its functional implications. J Biol Chem 2012; 287:8932-43. [PMID: 22267743 DOI: 10.1074/jbc.m111.294058] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
A mounting body of evidence suggests that β-arrestin-1 plays important roles in the nucleus, but how β-arrestin-1 enters the nucleus remains unclear because no nuclear import signal has been identified in the β-arrestins. We sought to characterize the cellular localization of wild type β-arrestin-1 and a series of N domain mutants to determine the structural basis and functional implications of β-arrestin-1 nuclear localization. A seven-residue candidate nuclear localization sequence (NLS) was identified based on sequence analysis. Mutation of the NLS led to a loss of β-arrestin-1 nuclear localization in transfected cells. Exogenous expression of wild type β-arrestin-1 enhanced the transcriptional activity of nuclear factor κB (NF-κB) induced by bradykinin, whereas mutation of the NLS reduced this effect by two-thirds relative to wild type controls. Loss of β-arrestin-1 nuclear localization was accompanied by reduced recruitment of the CREB-binding protein and altered post-translational modification profile of p65/RelA. Further mutational analysis identified Lys(157) within the putative NLS as being critical to nuclear localization of β-arrestin-1. Substitution of Lys(157) to Ala led to reduced nuclear localization, decreased promoter binding by p65/RelA and decreased IL-1β gene transcription. These results demonstrate a critical role for β-arrestin-1 nuclear localization in scaffolding and transcriptional regulation.
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Affiliation(s)
- Crystal Zoe Hoeppner
- Department of Pharmacology, College of Medicine, University of Illinois, Chicago, Illinois 60612, USA
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38
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Rebois RV, Hébert TE. Protein Complexes Involved in Heptahelical Receptor-Mediated Signal Transduction. ACTA ACUST UNITED AC 2011. [DOI: 10.3109/10606820308243] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Tilley DG. Functional relevance of biased signaling at the angiotensin II type 1 receptor. Endocr Metab Immune Disord Drug Targets 2011; 11:99-111. [PMID: 21476968 DOI: 10.2174/187153011795564133] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 02/07/2011] [Indexed: 01/04/2023]
Abstract
Angiotensin II type 1 receptor antagonists (AT1R blockers, or ARBs) are used commonly in the treatment of cardiovascular disorders such as heart failure and hypertension. Their clinical success arises from their ability to prevent deleterious Gα(q) protein activation downstream of AT1R, which leads to a decrease in morbidity and mortality. Recent studies have identified AT1R ligands that concurrently inhibit Gα(q) protein-dependent signaling and activate Gα(q) protein-independent/β-arrestin-dependent signaling downstream of AT1R, events that may actually improve cardiovascular performance more than conventional ARBs. The ability of such ligands to induce intracellular signaling events in an AT1R-β-arrestin-dependent manner while preventing AT1R-Gα(q) protein activity defines them as biased AT1R ligands. This mini-review will highlight recent studies that have defined biased signaling at the AT1R and discuss the possible clinical relevance of β-arrestin-biased AT1R ligands in the cardiovascular system.
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Affiliation(s)
- Douglas G Tilley
- Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University, Philadelphia, PA 1917, USA.
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Delom F, Fessart D. Role of Phosphorylation in the Control of Clathrin-Mediated Internalization of GPCR. Int J Cell Biol 2011; 2011:246954. [PMID: 21765832 PMCID: PMC3132527 DOI: 10.1155/2011/246954] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 04/01/2011] [Indexed: 12/17/2022] Open
Abstract
The process by which G protein-coupled receptors (GPCRs) are internalized through the clathrin-coated vesicles involves interactions of multifunctional adaptor proteins. These interactions are tightly controlled by phosphorylation and dephosphorylation mechanisms resulting in the regulation of receptor endocytosis. However, the identities of the kinases involved in this process remained largely unknown until recently. This paper discusses advances in our knowledge of the important role played by protein phosphorylation in the regulation of the endocytic machinery and how phosphorylation controls the coated vesicle cycle.
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Affiliation(s)
- Frederic Delom
- Bordeaux Cardiothoracic Research Center, Bordeaux University, 146, Léo-Saignat, 33076 Bordeaux, France
- Inserm U1045, 146, Léo-Saignat, 33076 Bordeaux, France
| | - Delphine Fessart
- Bordeaux Cardiothoracic Research Center, Bordeaux University, 146, Léo-Saignat, 33076 Bordeaux, France
- Inserm U1045, 146, Léo-Saignat, 33076 Bordeaux, France
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41
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42
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World C, Spindel ON, Berk BC. Thioredoxin-interacting protein mediates TRX1 translocation to the plasma membrane in response to tumor necrosis factor-α: a key mechanism for vascular endothelial growth factor receptor-2 transactivation by reactive oxygen species. Arterioscler Thromb Vasc Biol 2011; 31:1890-7. [PMID: 21636804 DOI: 10.1161/atvbaha.111.226340] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Thioredoxin-interacting protein (TXNIP) promotes inflammation in endothelial cells (EC) by binding to thioredoxin-1 (TRX1) in a redox-dependent manner. Formation of the TXNIP-TRX1 complex relieves inhibition of the apoptosis signal-regulating kinase 1-c-Jun N-terminal kinase-vascular cell adhesion molecule-1 pathway. Because TXNIP is an α-arrestin with numerous protein-protein interacting domains, we hypothesized that TXNIP-TRX1 trafficking should alter function of EC exposed to reactive oxygen species (ROS). METHODS AND RESULTS In response to physiological levels of ROS (10 ng/mL tumor necrosis factor-α and 30 μmol/L H(2)O(2)), TXNIP-TRX1 translocated to the plasma membrane in human umbilical vein EC, with a peak at 30 minutes, as measured by immunofluorescence colocalization with vascular endothelial-cadherin, cell fractionation, and membrane sheet assay. TXNIP-mediated translocation of TRX1 to the membrane required TXNIP and TRX1 binding, as evidenced by inability of the ROS-insensitive TXNIP-Cys247Ser mutant to promote membrane localization. Vascular endothelial growth factor signaling required TXNIP, as shown by significant decreases in plasma membrane tyrosine phosphorylation and EC migration after TRX1 knockdown. Furthermore, TXNIP knockdown increased human umbilical vein EC apoptosis induced by tumor necrosis factor. Rescue with TXNIP-wild-type but not TXNIP-Cys247Ser prevented cell death. CONCLUSIONS These findings suggest a novel role for the TXNIP-TRX1 complex to enable inflammation by promoting EC survival and vascular endothelial growth factor signaling under conditions of physiological oxidative stress.
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Affiliation(s)
- Cameron World
- Department of Medicine, University of Rochester School of Medicine and Dentistry, NY 14642, USA
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43
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Schuller HM. Beta-adrenergic signaling, a novel target for cancer therapy? Oncotarget 2010; 1:466-469. [PMID: 21317444 PMCID: PMC3248132 DOI: 10.18632/oncotarget.182] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 11/10/2010] [Indexed: 11/25/2022] Open
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DeFea KA. Beta-arrestins as regulators of signal termination and transduction: how do they determine what to scaffold? Cell Signal 2010; 23:621-9. [PMID: 20946952 DOI: 10.1016/j.cellsig.2010.10.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 09/17/2010] [Accepted: 10/01/2010] [Indexed: 01/07/2023]
Abstract
Over the last decade β-arrestins have emerged as pleiotropic scaffold proteins, capable of mediating numerous diverse responses to multiple agonists. Most well characterized are the G-protein-coupled receptor (GPCR) stimulated β-arrestin signals, which are sometimes synergistic with, and sometimes independent of, heterotrimeric G-protein signals. β-arrestin signaling involves the recruitment of downstream signaling moieties to β-arrestins; in many cases specific sites of interaction between β-arrestins and the downstream target have been identified. As more information unfolds about the nature of β-arrestin scaffolding interactions, it is evident that these proteins are capable of adopting multiple conformations which in turn reveal a specific set of interacting domains. Recruitment of β-arrestin to a specific GPCR can promote formation of a specific subset of available β-arrestin scaffolds, allowing for a higher level of specificity to given agonists. This review discusses recent advances in β-arrestin signaling, discussing the molecular details of a subset of known β-arrestin scaffolds and the significance of specific binding interactions on the ultimate cellular response.
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Affiliation(s)
- Kathryn A DeFea
- Biomedical Sciences Division, University of California-Riverside, CA 92521, USA.
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45
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Luttrell LM, Gesty-Palmer D. Beyond desensitization: physiological relevance of arrestin-dependent signaling. Pharmacol Rev 2010; 62:305-30. [PMID: 20427692 DOI: 10.1124/pr.109.002436] [Citation(s) in RCA: 321] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Heptahelical G protein-coupled receptors are the most diverse and therapeutically important family of receptors in the human genome. Ligand binding activates heterotrimeric G proteins that transmit intracellular signals by regulating effector enzymes or ion channels. G protein signaling is terminated, in large part, by arrestin binding, which uncouples the receptor and G protein and targets the receptor for internalization. It is clear, however, that heptahelical receptor signaling does not end with desensitization. Arrestins bind a host of catalytically active proteins and serve as ligand-regulated scaffolds that recruit protein and lipid kinase, phosphatase, phosphodiesterase, and ubiquitin ligase activity into the receptor-arrestin complex. Although many of these arrestin-bound effectors serve to modulate G protein signaling, degrading second messengers and regulating endocytosis and trafficking, other signals seem to extend beyond the receptor-arrestin complex to regulate such processes as protein translation and gene transcription. Although these findings have led to a re-envisioning of heptahelical receptor signaling, little is known about the physiological roles of arrestin-dependent signaling. In vivo, the duality of arrestin function makes it difficult to dissociate the consequences of arrestin-dependent desensitization from those that might be ascribed to arrestin-mediated signaling. Nonetheless, recent evidence generated using arrestin knockouts, G protein-uncoupled receptor mutants, and arrestin pathway-selective "biased agonists" is beginning to reveal that arrestin signaling plays important roles in the retina, central nervous system, cardiovascular system, bone remodeling, immune system, and cancer. Understanding the signaling roles of arrestins may foster the development of pathway-selective drugs that exploit these pathways for therapeutic benefit.
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Affiliation(s)
- Louis M Luttrell
- Department of Medicine, Medical University of South Carolina, USA
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46
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Bamberg CE, Mackay CR, Lee H, Zahra D, Jackson J, Lim YS, Whitfeld PL, Craig S, Corsini E, Lu B, Gerard C, Gerard NP. The C5a receptor (C5aR) C5L2 is a modulator of C5aR-mediated signal transduction. J Biol Chem 2009; 285:7633-44. [PMID: 20044484 DOI: 10.1074/jbc.m109.092106] [Citation(s) in RCA: 188] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The complement anaphylatoxin C5a is a proinflammatory component of host defense that functions through two identified receptors, C5a receptor (C5aR) and C5L2. C5aR is a classical G protein-coupled receptor, whereas C5L2 is structurally homologous but deficient in G protein coupling. In human neutrophils, we show C5L2 is predominantly intracellular, whereas C5aR is expressed on the plasma membrane. Confocal analysis shows internalized C5aR following ligand binding is co-localized with both C5L2 and beta-arrestin. Antibody blockade of C5L2 results in a dramatic increase in C5a-mediated chemotaxis and ERK1/2 phosphorylation but does not alter C5a-mediated calcium mobilization, supporting its role in modulation of the beta-arrestin pathway. Association of C5L2 with beta-arrestin is confirmed by cellular co-immunoprecipitation assays. C5L2 blockade also has no effect on ligand uptake or C5aR endocytosis in human polymorphonuclear leukocytes, distinguishing its role from that of a rapid recycling or scavenging receptor in this cell type. This is thus the first example of a naturally occurring seven-transmembrane segment receptor that is both obligately uncoupled from G proteins and a negative modulator of signal transduction through the beta-arrestin pathway. Physiologically, these properties provide the possibility for additional fine-tuning of host defense.
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Affiliation(s)
- Claire E Bamberg
- Pulmonary Division, Department of Pediatrics, Children's Hospital, Boston, Massachusetts 02115, USA
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47
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Kendall RT, Luttrell LM. Diversity in arrestin function. Cell Mol Life Sci 2009; 66:2953-73. [PMID: 19597700 PMCID: PMC11115578 DOI: 10.1007/s00018-009-0088-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 05/09/2009] [Accepted: 05/12/2009] [Indexed: 01/08/2023]
Abstract
The termination of heptahelical receptor signaling is a multilevel process coordinated, in large part, by members of the arrestin family of proteins. Arrestin binding to agonist-occupied receptors promotes desensitization by interrupting receptor-G protein coupling, while simultaneously recruiting machinery for receptor endocytosis, vesicular trafficking, and receptor fate determination. By simultaneously binding other proteins, arrestins also act as ligand-regulated scaffolds that recruit protein and lipid kinase, phosphatase, phosphodiesterase, and ubiquitin ligase activity into receptor-based multiprotein 'signalsome' complexes. Arrestin-binding thus 'switches' receptors from a transient G protein-coupled state to a persistent arrestin-coupled state that continues to signal as the receptor transits intracellular compartments. While it is clear that signalsome assembly has profound effects on the duration and spatial characteristics of heptahelical receptor signals, the physiologic functions of this novel signaling mechanism are poorly understood. Growing evidence suggests that signalsomes regulate such diverse processes as endocytosis and exocytosis, cell migration, survival, and contractility.
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Affiliation(s)
- Ryan T. Kendall
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Louis M. Luttrell
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425 USA
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425 USA
- Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC 29401 USA
- Division of Endocrinology, Diabetes and Medical Genetics, Medical University of South Carolina, 96 Jonathan Lucas Street, Suite 816 CSB, MSC 624, Charleston, SC 29425 USA
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48
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Micevych P, Dominguez R. Membrane estradiol signaling in the brain. Front Neuroendocrinol 2009; 30:315-27. [PMID: 19416735 PMCID: PMC2720427 DOI: 10.1016/j.yfrne.2009.04.011] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 04/22/2009] [Accepted: 04/23/2009] [Indexed: 12/16/2022]
Abstract
While the physiology of membrane-initiated estradiol signaling in the nervous system has remained elusive, a great deal of progress has been made toward understanding the activation of cell signaling. Membrane-initiated estradiol signaling activates G proteins and their downstream cascades, but the identity of membrane receptors and the proximal signaling mechanism(s) have been more difficult to elucidate. Mounting evidence suggests that classical intracellular estrogen receptor-alpha (ERalpha) and ERbeta are trafficked to the membrane to mediate estradiol cell signaling. Moreover, an interaction of membrane ERalpha and ERbeta with metabotropic glutamate receptors has been identified that explains the pleomorphic actions of membrane-initiated estradiol signaling. This review focuses on the mechanism of actions initiated by membrane estradiol receptors and discusses the role of scaffold proteins and signaling cascades involved in the regulation of nociception, sexual receptivity and the synthesis of neuroprogesterone, an important component in the central nervous system signaling.
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Affiliation(s)
- Paul Micevych
- Department of Neurobiology and the Laboratory of Neuroendocrinology David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-1763, USA.
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Meng D, Lynch MJ, Huston E, Beyermann M, Eichhorst J, Adams DR, Klussmann E, Klusmann E, Houslay MD, Baillie GS. MEK1 binds directly to betaarrestin1, influencing both its phosphorylation by ERK and the timing of its isoprenaline-stimulated internalization. J Biol Chem 2009; 284:11425-35. [PMID: 19153083 PMCID: PMC2670148 DOI: 10.1074/jbc.m806395200] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 01/12/2009] [Indexed: 01/14/2023] Open
Abstract
betaArrestin is a multifunctional signal scaffold protein. Using SPOT immobilized peptide arrays, coupled with scanning alanine substitution and mutagenesis, we show that the MAPK kinase, MEK1, interacts directly with betaarrestin1. Asp(26) and Asp(29) in the N-terminal domain of betaarrestin1 are critical for its binding to MEK1, whereas Arg(47) and Arg(49) in the N-terminal domain of MEK1 are critical for its binding to betaarrestin1. Wild-type FLAG-tagged betaarrestin1 co-immunopurifies with MEK1 in HEKB2 cells, whereas the D26A/D29A mutant does not. ERK-dependent phosphorylation at Ser(412) was compromised in the D26A/D29A-betaarrestin1 mutant. A cell-permeable, 25-mer N-stearoylated betaarrestin1 peptide that encompassed the N-domain MEK1 binding site blocked betaarrestin1/MEK1 association in HEK cells and recapitulated the altered phenotype seen with the D26A/D29A-betaarrestin1 in compromising the ERK-dependent phosphorylation of betaarrestin1. In addition, the MEK disruptor peptide promoted the ability of betaarrestin1 to co-immunoprecipitate with endogenous c-Src and clathrin, facilitating the isoprenaline-stimulated internalization of the beta(2)-adrenergic receptor.
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Affiliation(s)
- Dong Meng
- Neuroscience and Molecular Pharmacology, Faculty of Biomedical and Life Sciences, Wolfson Building, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
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17beta-estradiol-mediated neuroprotection and ERK activation require a pertussis toxin-sensitive mechanism involving GRK2 and beta-arrestin-1. J Neurosci 2009; 29:4228-38. [PMID: 19339617 DOI: 10.1523/jneurosci.0550-09.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
17-beta-Estradiol (E2) is a steroid hormone involved in numerous bodily functions, including several brain functions. In particular, E2 is neuroprotective against excitotoxicity and other forms of brain injuries, a property that requires the extracellular signal-regulated kinase (ERK) pathway and possibly that of other signaling molecules. The mechanism and identity of the receptor(s) involved remain unclear, although it has been suggested that E2 receptor alpha (ERalpha) and G proteins are involved. We, therefore, investigated whether E2-mediated neuroprotection and ERK activation were linked to pertussis toxin (PTX)-sensitive G-protein-coupled effector systems. Biochemical and image analysis of organotypic hippocampal slices and cortical neuronal cultures showed that E2-mediated neuroprotection as well as E2-induced ERK activation were sensitive to PTX. The sensitivity to PTX suggested a possible role of G-protein- and beta-arrestin-mediated mechanisms. Western immunoblots from E2-treated cortical neuronal cultures revealed an increase in phosphorylation of both G-protein-coupled receptor-kinase 2 and beta-arrestin-1, a G-protein-coupled receptor adaptor protein. Transfection of neurons with beta-arrestin-1 small interfering RNA prevented E2-induced ERK activation. Coimmunoprecipitation experiments indicated that E2 increased the recruitment of beta-arrestin-1 and c-Src to ERalpha. These findings suggested that ERalpha is regulated by a mechanism associated with receptor desensitization and downregulation. In support of this idea, we found that E2 treatment of cortical synaptoneurosomes resulted in internalization of ERalpha, whereas treatment of cortical neurons with the ER agonists E-6-BSA-FITC [beta-estradiol-6-(O-carboxymethyl)oxime-bovine serum albumin conjugated with fluorescein isothiocyanate] and E-6-biotin [1,3,5(10)-estratrien-3,17beta-diol-6-one-6-carboxymethloxime-NH-propyl-biotin] resulted in agonist internalization. These results demonstrate that E2-mediated neuroprotection and ERK activation involve ERalpha activation of G-protein- and beta-arrestin-mediated mechanisms.
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