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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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Wess J, Oteng AB, Rivera-Gonzalez O, Gurevich EV, Gurevich VV. β-Arrestins: Structure, Function, Physiology, and Pharmacological Perspectives. Pharmacol Rev 2023; 75:854-884. [PMID: 37028945 PMCID: PMC10441628 DOI: 10.1124/pharmrev.121.000302] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/23/2023] [Accepted: 04/03/2023] [Indexed: 04/09/2023] Open
Abstract
The two β-arrestins, β-arrestin-1 and -2 (systematic names: arrestin-2 and -3, respectively), are multifunctional intracellular proteins that regulate the activity of a very large number of cellular signaling pathways and physiologic functions. The two proteins were discovered for their ability to disrupt signaling via G protein-coupled receptors (GPCRs) via binding to the activated receptors. However, it is now well recognized that both β-arrestins can also act as direct modulators of numerous cellular processes via either GPCR-dependent or -independent mechanisms. Recent structural, biophysical, and biochemical studies have provided novel insights into how β-arrestins bind to activated GPCRs and downstream effector proteins. Studies with β-arrestin mutant mice have identified numerous physiologic and pathophysiological processes regulated by β-arrestin-1 and/or -2. Following a short summary of recent structural studies, this review primarily focuses on β-arrestin-regulated physiologic functions, with particular focus on the central nervous system and the roles of β-arrestins in carcinogenesis and key metabolic processes including the maintenance of glucose and energy homeostasis. This review also highlights potential therapeutic implications of these studies and discusses strategies that could prove useful for targeting specific β-arrestin-regulated signaling pathways for therapeutic purposes. SIGNIFICANCE STATEMENT: The two β-arrestins, structurally closely related intracellular proteins that are evolutionarily highly conserved, have emerged as multifunctional proteins able to regulate a vast array of cellular and physiological functions. The outcome of studies with β-arrestin mutant mice and cultured cells, complemented by novel insights into β-arrestin structure and function, should pave the way for the development of novel classes of therapeutically useful drugs capable of regulating specific β-arrestin functions.
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Affiliation(s)
- Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland (J.W., A.-B.O., O.R.-G.); and Department of Pharmacology, Vanderbilt University, Nashville, Tennessee (E.V.G., V.V.G.)
| | - Antwi-Boasiako Oteng
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland (J.W., A.-B.O., O.R.-G.); and Department of Pharmacology, Vanderbilt University, Nashville, Tennessee (E.V.G., V.V.G.)
| | - Osvaldo Rivera-Gonzalez
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland (J.W., A.-B.O., O.R.-G.); and Department of Pharmacology, Vanderbilt University, Nashville, Tennessee (E.V.G., V.V.G.)
| | - Eugenia V Gurevich
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland (J.W., A.-B.O., O.R.-G.); and Department of Pharmacology, Vanderbilt University, Nashville, Tennessee (E.V.G., V.V.G.)
| | - Vsevolod V Gurevich
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland (J.W., A.-B.O., O.R.-G.); and Department of Pharmacology, Vanderbilt University, Nashville, Tennessee (E.V.G., V.V.G.)
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Vishnivetskiy SA, Zhan X, Gurevich VV. Expression of Untagged Arrestins in E. coli and Their Purification. Curr Protoc 2023; 3:e832. [PMID: 37671938 PMCID: PMC10491425 DOI: 10.1002/cpz1.832] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Purified arrestin proteins are necessary for biochemical, biophysical, and structural studies of these versatile regulators of cell signaling. Described herein is a basic protocol for arrestin expression in Escherichia coli and purification of tag-free wild-type and mutant arrestins. The method includes ammonium sulfate precipitation of arrestins from cell lysates, followed by Heparin-Sepharose chromatography. Depending on the arrestin type and/or mutations, the next step is Q-Sepharose or SP-Sepharose chromatography. In many cases, the nonbinding column is used as a filter to bind contaminants without retaining arrestin. In some cases, both chromatographic steps must be performed sequentially to achieve high purity. Purified arrestins can be concentrated up to 10 mg/ml, remain fully functional, and withstand several cycles of freezing and thawing, provided that the overall salt concentration is maintained at or above physiological levels. © 2023 Wiley Periodicals LLC. Basic Protocol: Large-scale expression and purification of arrestins Alternate Protocol: Purification of arrestin-3 and truncated form of arrestin-1-(1-378) Support Protocol: Small-scale test expression of wild-type and mutant arrestins in E. coli.
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Affiliation(s)
| | - Xuanzhi Zhan
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
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The Role of Arrestin-1 Middle Loop in Rhodopsin Binding. Int J Mol Sci 2022; 23:ijms232213887. [PMID: 36430370 PMCID: PMC9694801 DOI: 10.3390/ijms232213887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Arrestins preferentially bind active phosphorylated G protein-coupled receptors (GPCRs). The middle loop, highly conserved in all arrestin subtypes, is localized in the central crest on the GPCR-binding side. Upon receptor binding, it directly interacts with bound GPCR and demonstrates the largest movement of any arrestin element in the structures of the complexes. Comprehensive mutagenesis of the middle loop of rhodopsin-specific arrestin-1 suggests that it primarily serves as a suppressor of binding to non-preferred forms of the receptor. Several mutations in the middle loop increase the binding to unphosphorylated light-activated rhodopsin severalfold, which makes them candidates for improving enhanced phosphorylation-independent arrestins. The data also suggest that enhanced forms of arrestin do not bind GPCRs exactly like the wild-type protein. Thus, the structures of the arrestin-receptor complexes, in all of which different enhanced arrestin mutants and reengineered receptors were used, must be interpreted with caution.
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Gurevich VV, Gurevich EV. Solo vs. Chorus: Monomers and Oligomers of Arrestin Proteins. Int J Mol Sci 2022; 23:ijms23137253. [PMID: 35806256 PMCID: PMC9266314 DOI: 10.3390/ijms23137253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 02/05/2023] Open
Abstract
Three out of four subtypes of arrestin proteins expressed in mammals self-associate, each forming oligomers of a distinct kind. Monomers and oligomers have different subcellular localization and distinct biological functions. Here we summarize existing evidence regarding arrestin oligomerization and discuss specific functions of monomeric and oligomeric forms, although too few of the latter are known. The data on arrestins highlight biological importance of oligomerization of signaling proteins. Distinct modes of oligomerization might be an important contributing factor to the functional differences among highly homologous members of the arrestin protein family.
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Hsieh CL, Yao Y, Gurevich VV, Chen J. Arrestin Facilitates Rhodopsin Dephosphorylation in Vivo. J Neurosci 2022; 42:3537-3545. [PMID: 35332081 PMCID: PMC9053844 DOI: 10.1523/jneurosci.0141-22.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/08/2022] [Accepted: 03/17/2022] [Indexed: 01/14/2023] Open
Abstract
Deactivation of G-protein-coupled receptors (GPCRs) involves multiple phosphorylations followed by arrestin binding, which uncouples the GPCR from G-protein activation. Some GPCRs, such as rhodopsin, are reused many times. Arrestin dissociation and GPCR dephosphorylation are key steps in the recycling process. In vitro evidence suggests that visual arrestin (ARR1) binding to light-activated, phosphorylated rhodopsin hinders dephosphorylation. Whether ARR1 binding also affects rhodopsin dephosphorylation in vivo is not known. We investigated this using both male and female mice lacking ARR1. Mice were exposed to bright light and placed in darkness for different periods of time, and differently phosphorylated species of rhodopsin were assayed by isoelectric focusing. For WT mice, rhodopsin dephosphorylation was nearly complete by 1 h in darkness. Surprisingly, we observed that, in the Arr1 KO rods, rhodopsin remained phosphorylated even after 3 h. Delayed dephosphorylation in Arr1 KO rods cannot be explained by cell stress induced by persistent signaling, since it is not prevented by the removal of transducin, the visual G-protein, nor can it be explained by downregulation of protein phosphatase 2A, the putative rhodopsin phosphatase. We further show that cone arrestin (ARR4), which binds light-activated, phosphorylated rhodopsin poorly, had little effect in enhancing rhodopsin dephosphorylation, whereas mice expressing binding-competent mutant ARR1-3A showed a similar time course of rhodopsin dephosphorylation as WT. Together, these results reveal a novel role of ARR1 in facilitating rhodopsin dephosphorylation in vivoSIGNIFICANCE STATEMENT G-protein-coupled receptors (GPCRs) are transmembrane proteins used by cells to receive and respond to a broad range of extracellular signals that include neurotransmitters, hormones, odorants, and light (photons). GPCR signaling is terminated by two sequential steps: phosphorylation and arrestin binding. Both steps must be reversed when GPCRs are recycled and reused. Dephosphorylation, which is required for recycling, is an understudied process. Using rhodopsin as a prototypical GPCR, we discovered that arrestin facilitated rhodopsin dephosphorylation in living mice.
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Affiliation(s)
- Chia-Ling Hsieh
- Ziliha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90089
| | - Yun Yao
- Ziliha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90089
| | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232
| | - Jeannie Chen
- Ziliha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90089
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Schöneberg T, Liebscher I. Mutations in G Protein-Coupled Receptors: Mechanisms, Pathophysiology and Potential Therapeutic Approaches. Pharmacol Rev 2020; 73:89-119. [PMID: 33219147 DOI: 10.1124/pharmrev.120.000011] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
There are approximately 800 annotated G protein-coupled receptor (GPCR) genes, making these membrane receptors members of the most abundant gene family in the human genome. Besides being involved in manifold physiologic functions and serving as important pharmacotherapeutic targets, mutations in 55 GPCR genes cause about 66 inherited monogenic diseases in humans. Alterations of nine GPCR genes are causatively involved in inherited digenic diseases. In addition to classic gain- and loss-of-function variants, other aspects, such as biased signaling, trans-signaling, ectopic expression, allele variants of GPCRs, pseudogenes, gene fusion, and gene dosage, contribute to the repertoire of GPCR dysfunctions. However, the spectrum of alterations and GPCR involvement is probably much larger because an additional 91 GPCR genes contain homozygous or hemizygous loss-of-function mutations in human individuals with currently unidentified phenotypes. This review highlights the complexity of genomic alteration of GPCR genes as well as their functional consequences and discusses derived therapeutic approaches. SIGNIFICANCE STATEMENT: With the advent of new transgenic and sequencing technologies, the number of monogenic diseases related to G protein-coupled receptor (GPCR) mutants has significantly increased, and our understanding of the functional impact of certain kinds of mutations has substantially improved. Besides the classical gain- and loss-of-function alterations, additional aspects, such as biased signaling, trans-signaling, ectopic expression, allele variants of GPCRs, uniparental disomy, pseudogenes, gene fusion, and gene dosage, need to be elaborated in light of GPCR dysfunctions and possible therapeutic strategies.
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Affiliation(s)
- Torsten Schöneberg
- Rudolf Schönheimer Institute of Biochemistry, Molecular Biochemistry, Medical Faculty, Leipzig, Germany
| | - Ines Liebscher
- Rudolf Schönheimer Institute of Biochemistry, Molecular Biochemistry, Medical Faculty, Leipzig, Germany
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Biological Role of Arrestin-1 Oligomerization. J Neurosci 2020; 40:8055-8069. [PMID: 32948676 DOI: 10.1523/jneurosci.0749-20.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 11/21/2022] Open
Abstract
Members of the arrestin superfamily have great propensity of self-association, but the physiological significance of this phenomenon is unclear. To determine the biological role of visual arrestin-1 oligomerization in rod photoreceptors, we expressed mutant arrestin-1 with severely impaired self-association in mouse rods and analyzed mice of both sexes. We show that the oligomerization-deficient mutant is capable of quenching rhodopsin signaling normally, as judged by electroretinography and single-cell recording. Like wild type, mutant arrestin-1 is largely excluded from the outer segments in the dark, proving that the normal intracellular localization is not due the size exclusion of arrestin-1 oligomers. In contrast to wild type, supraphysiological expression of the mutant causes shortening of the outer segments and photoreceptor death. Thus, oligomerization reduces the cytotoxicity of arrestin-1 monomer, ensuring long-term photoreceptor survival.SIGNIFICANCE STATEMENT Visual arrestin-1 forms dimers and tetramers. The biological role of its oligomerization is unclear. To test the role of arrestin-1 self-association, we expressed oligomerization-deficient mutant in arrestin-1 knock-out mice. The mutant quenches light-induced rhodopsin signaling like wild type, demonstrating that in vivo monomeric arrestin-1 is necessary and sufficient for this function. In rods, arrestin-1 moves from the inner segments and cell bodies in the dark to the outer segments in the light. Nonoligomerizing mutant undergoes the same translocation, demonstrating that the size of the oligomers is not the reason for arrestin-1 exclusion from the outer segments in the dark. High expression of oligomerization-deficient arrestin-1 resulted in rod death. Thus, oligomerization reduces the cytotoxicity of high levels of arrestin-1 monomer.
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Gurevich VV, Gurevich EV. Targeting arrestin interactions with its partners for therapeutic purposes. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 121:169-197. [PMID: 32312421 DOI: 10.1016/bs.apcsb.2019.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Most vertebrates express four arrestin subtypes: two visual ones in photoreceptor cells and two non-visuals expressed ubiquitously. The latter two interact with hundreds of G protein-coupled receptors, certain receptors of other types, and numerous non-receptor partners. Arrestins have no enzymatic activity and work by interacting with other proteins, often assembling multi-protein signaling complexes. Arrestin binding to every partner affects cell signaling, including pathways regulating cell survival, proliferation, and death. Thus, targeting individual arrestin interactions has therapeutic potential. This requires precise identification of protein-protein interaction sites of both participants and the choice of the side of each interaction which would be most advantageous to target. The interfaces involved in each interaction can be disrupted by small molecule therapeutics, as well as by carefully selected peptides of the other partner that do not participate in the interactions that should not be targeted.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
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Critical role of the finger loop in arrestin binding to the receptors. PLoS One 2019; 14:e0213792. [PMID: 30875392 PMCID: PMC6420155 DOI: 10.1371/journal.pone.0213792] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 02/28/2019] [Indexed: 12/18/2022] Open
Abstract
We tested the interactions with four different G protein-coupled receptors (GPCRs) of arrestin-3 mutants with substitutions in the four loops, three of which contact the receptor in the structure of the arrestin-1-rhodopsin complex. Point mutations in the loop at the distal tip of the N-domain (Glu157Ala), in the C-loop (Phe255Ala), back loop (Lys313Ala), and one of the mutations in the finger loop (Gly65Pro) had mild variable effects on receptor binding. In contrast, the deletion of Gly65 at the beginning of the finger loop reduced the binding to all GPCRs tested, with the binding to dopamine D2 receptor being affected most dramatically. Thus, the presence of a glycine at the beginning of the finger loop appears to be critical for the arrestin-receptor interaction.
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Gurevich VV, Gurevich EV. GPCR Signaling Regulation: The Role of GRKs and Arrestins. Front Pharmacol 2019; 10:125. [PMID: 30837883 PMCID: PMC6389790 DOI: 10.3389/fphar.2019.00125] [Citation(s) in RCA: 330] [Impact Index Per Article: 66.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/31/2019] [Indexed: 12/13/2022] Open
Abstract
Every animal species expresses hundreds of different G protein-coupled receptors (GPCRs) that respond to a wide variety of external stimuli. GPCRs-driven signaling pathways are involved in pretty much every physiological function and in many pathologies. Therefore, GPCRs are targeted by about a third of clinically used drugs. The signaling of most GPCRs via G proteins is terminated by the phosphorylation of active receptor by specific kinases (GPCR kinases, or GRKs) and subsequent binding of arrestin proteins, that selectively recognize active phosphorylated receptors. In addition, GRKs and arrestins play a role in multiple signaling pathways in the cell, both GPCR-initiated and receptor-independent. Here we focus on the mechanisms of GRK- and arrestin-mediated regulation of GPCR signaling, which includes homologous desensitization and redirection of signaling to additional pathways by bound arrestins.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
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Gurevich VV, Chen Q, Gurevich EV. Arrestins: Introducing Signaling Bias Into Multifunctional Proteins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 160:47-61. [PMID: 30470292 DOI: 10.1016/bs.pmbts.2018.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Arrestins were discovered as proteins that bind active phosphorylated G protein-coupled receptors (GPCRs) and block their interactions with G proteins, i.e., for their role in homologous desensitization of GPCRs. Mammals express only four arrestin subtypes, two of which are largely restricted to the retina. Two nonvisual arrestins are ubiquitous and interact with hundreds of different GPCRs and dozens of other binding partners. Changes of just a few residues on the receptor-binding surface were shown to dramatically affect GPCR preference of inherently promiscuous nonvisual arrestins. Mutations on the cytosol-facing side of arrestins modulate their interactions with individual downstream signaling molecules. Thus, it appears feasible to construct arrestin mutants specifically linking particular GPCRs with signaling pathways of choice or mutants that sever the links between selected GPCRs and unwanted pathways. Signaling-biased "designer arrestins" have the potential to become valuable molecular tools for research and therapy.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States.
| | - Qiuyan Chen
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
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Vishnivetskiy SA, Sullivan LS, Bowne SJ, Daiger SP, Gurevich EV, Gurevich VV. Molecular Defects of the Disease-Causing Human Arrestin-1 C147F Mutant. Invest Ophthalmol Vis Sci 2018; 59:13-20. [PMID: 29305604 PMCID: PMC5756042 DOI: 10.1167/iovs.17-22180] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Purpose The purpose of this study was to identify the molecular defect in the disease-causing human arrestin-1 C147F mutant. Methods The binding of wild-type (WT) human arrestin-1 and several mutants with substitutions in position 147 (including C147F, which causes dominant retinitis pigmentosa in humans) to phosphorylated and unphosphorylated light-activated rhodopsin was determined. Thermal stability of WT and mutant human arrestin-1, as well as unfolded protein response in 661W cells, were also evaluated. Results WT human arrestin-1 was selective for phosphorylated light-activated rhodopsin. Substitutions of Cys-147 with smaller side chain residues, Ala or Val, did not substantially affect binding selectivity, whereas residues with bulky side chains in the position 147 (Ile, Leu, and disease-causing Phe) greatly increased the binding to unphosphorylated rhodopsin. Functional survival of mutant proteins with bulky substitutions at physiological and elevated temperature was also compromised. C147F mutant induced unfolded protein response in cultured cells. Conclusions Bulky Phe substitution of Cys-147 in human arrestin-1 likely causes rod degeneration due to reduced stability of the protein, which induces unfolded protein response in expressing cells.
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Affiliation(s)
| | - Lori S Sullivan
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center, Houston, Texas, United States
| | - Sara J Bowne
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center, Houston, Texas, United States
| | - Stephen P Daiger
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center, Houston, Texas, United States
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States
| | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States
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Samaranayake S, Song X, Vishnivetskiy SA, Chen J, Gurevich EV, Gurevich VV. Enhanced Mutant Compensates for Defects in Rhodopsin Phosphorylation in the Presence of Endogenous Arrestin-1. Front Mol Neurosci 2018; 11:203. [PMID: 29973866 PMCID: PMC6020793 DOI: 10.3389/fnmol.2018.00203] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/22/2018] [Indexed: 01/16/2023] Open
Abstract
We determined the effects of different expression levels of arrestin-1-3A mutant with enhanced binding to light-activated rhodopsin that is independent of phosphorylation. To this end, transgenic mice that express mutant rhodopsin with zero, one, or two phosphorylation sites, instead of six in the WT mouse rhodopsin, and normal complement of WT arrestin-1, were bred with mice expressing enhanced phosphorylation-independent arrestin-1-3A mutant. The resulting lines were characterized by retinal histology (thickness of the outer nuclear layer, reflecting the number of rod photoreceptors, and the length of the outer segments, which reflects rod health), as well as single- and double-flash ERG to determine the functionality of rods and the rate of photoresponse recovery. The effect of co-expression of enhanced arrestin-1-3A mutant with WT arrestin-1 in these lines depended on its level: higher (240% of WT) expression reduced the thickness of ONL and the length of OS, whereas lower (50% of WT) expression was harmless in the retinas expressing rhodopsin with zero or one phosphorylation site, and improved photoreceptor morphology in animals expressing rhodopsin with two phosphorylation sites. Neither expression level increased the amplitude of the a- and b-wave of the photoresponse in any of the lines. However, high expression of enhanced arrestin-1-3A mutant facilitated photoresponse recovery 2-3-fold, whereas lower level was ineffective. Thus, in the presence of normal complement of WT arrestin-1 only supra-physiological expression of enhanced mutant is sufficient to compensate for the defects of rhodopsin phosphorylation.
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Affiliation(s)
- Srimal Samaranayake
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Xiufeng Song
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | | | - Jeannie Chen
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Eugenia V. Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
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Gurevich VV, Gurevich EV, Uversky VN. Arrestins: structural disorder creates rich functionality. Protein Cell 2018; 9:986-1003. [PMID: 29453740 PMCID: PMC6251804 DOI: 10.1007/s13238-017-0501-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 11/27/2017] [Indexed: 01/14/2023] Open
Abstract
Arrestins are soluble relatively small 44–46 kDa proteins that specifically bind hundreds of active phosphorylated GPCRs and dozens of non-receptor partners. There are binding partners that demonstrate preference for each of the known arrestin conformations: free, receptor-bound, and microtubule-bound. Recent evidence suggests that conformational flexibility in every functional state is the defining characteristic of arrestins. Flexibility, or plasticity, of proteins is often described as structural disorder, in contrast to the fixed conformational order observed in high-resolution crystal structures. However, protein-protein interactions often involve highly flexible elements that can assume many distinct conformations upon binding to different partners. Existing evidence suggests that arrestins are no exception to this rule: their flexibility is necessary for functional versatility. The data on arrestins and many other multi-functional proteins indicate that in many cases, “order” might be artificially imposed by highly non-physiological crystallization conditions and/or crystal packing forces. In contrast, conformational flexibility (and its extreme case, intrinsic disorder) is a more natural state of proteins, representing true biological order that underlies their physiologically relevant functions.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA.
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.,Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
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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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17
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Molecular Mechanisms of GPCR Signaling: A Structural Perspective. Int J Mol Sci 2017; 18:ijms18122519. [PMID: 29186792 PMCID: PMC5751122 DOI: 10.3390/ijms18122519] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 01/06/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are cell surface receptors that respond to a wide variety of stimuli, from light, odorants, hormones, and neurotransmitters to proteins and extracellular calcium. GPCRs represent the largest family of signaling proteins targeted by many clinically used drugs. Recent studies shed light on the conformational changes that accompany GPCR activation and the structural state of the receptor necessary for the interactions with the three classes of proteins that preferentially bind active GPCRs, G proteins, G protein-coupled receptor kinases (GRKs), and arrestins. Importantly, structural and biophysical studies also revealed activation-related conformational changes in these three types of signal transducers. Here, we summarize what is already known and point out questions that still need to be answered. Clear understanding of the structural basis of signaling by GPCRs and their interaction partners would pave the way to designing signaling-biased proteins with scientific and therapeutic potential.
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18
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Frederiksen R, Nymark S, Kolesnikov AV, Berry JD, Adler L, Koutalos Y, Kefalov VJ, Cornwall MC. Rhodopsin kinase and arrestin binding control the decay of photoactivated rhodopsin and dark adaptation of mouse rods. J Gen Physiol 2017; 148:1-11. [PMID: 27353443 PMCID: PMC4924931 DOI: 10.1085/jgp.201511538] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 06/06/2016] [Indexed: 12/22/2022] Open
Abstract
G-protein receptor kinase and arrestin 1 are required for inactivation of photoactivated vertebrate rhodopsin. Frederiksen et al. show that they additionally regulate the subsequent decay of inactive rhodopsin into opsin and all-trans retinal and therefore dark adaptation. Photoactivation of vertebrate rhodopsin converts it to the physiologically active Meta II (R*) state, which triggers the rod light response. Meta II is rapidly inactivated by the phosphorylation of C-terminal serine and threonine residues by G-protein receptor kinase (Grk1) and subsequent binding of arrestin 1 (Arr1). Meta II exists in equilibrium with the more stable inactive form of rhodopsin, Meta III. Dark adaptation of rods requires the complete thermal decay of Meta II/Meta III into opsin and all-trans retinal and the subsequent regeneration of rhodopsin with 11-cis retinal chromophore. In this study, we examine the regulation of Meta III decay by Grk1 and Arr1 in intact mouse rods and their effect on rod dark adaptation. We measure the rates of Meta III decay in isolated retinas of wild-type (WT), Grk1-deficient (Grk1−/−), Arr1-deficient (Arr1−/−), and Arr1-overexpressing (Arr1ox) mice. We find that in WT mouse rods, Meta III peaks ∼6 min after rhodopsin activation and decays with a time constant (τ) of 17 min. Meta III decay slows in Arr1−/− rods (τ of ∼27 min), whereas it accelerates in Arr1ox rods (τ of ∼8 min) and Grk1−/− rods (τ of ∼13 min). In all cases, regeneration of rhodopsin with exogenous 11-cis retinal is rate limited by the decay of Meta III. Notably, the kinetics of rod dark adaptation in vivo is also modulated by the levels of Arr1 and Grk1. We conclude that, in addition to their well-established roles in Meta II inactivation, Grk1 and Arr1 can modulate the kinetics of Meta III decay and rod dark adaptation in vivo.
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Affiliation(s)
- Rikard Frederiksen
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Soile Nymark
- Department of Electronics and Communications Engineering, BioMediTech, Tampere University of Technology, 33720 Tampere, Finland
| | - Alexander V Kolesnikov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110
| | - Justin D Berry
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Leopold Adler
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425
| | - Yiannis Koutalos
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425
| | - Vladimir J Kefalov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110
| | - M Carter Cornwall
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
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19
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Feng D, Chen Z, Yang K, Miao S, Xu B, Kang Y, Xie H, Zhao C. The cytoplasmic tail of rhodopsin triggers rapid rod degeneration in kinesin-2 mutants. J Biol Chem 2017; 292:17375-17386. [PMID: 28855254 DOI: 10.1074/jbc.m117.784017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/24/2017] [Indexed: 11/06/2022] Open
Abstract
Photoreceptor degeneration can lead to blindness and represents the most common form of neural degenerative disease worldwide. Although many genes involved in photoreceptor degeneration have been identified, the underlying mechanisms remain to be elucidated. Here we examined photoreceptor development in zebrafish kif3a and kif3b mutants, which affect two subunits of the kinesin-2 complex. In both mutants, rods degenerated quickly, whereas cones underwent a slow degeneration process. Notably, the photoreceptor defects were considerably more severe in kif3a mutants than in kif3b mutants. In the cone photoreceptors of kif3a mutants, opsin proteins accumulated in the apical region and formed abnormal membrane structures. In contrast, rhodopsins were enriched in the rod cell body membrane and represented the primary reason for rapid rod degeneration in these mutants. Moreover, removal of the cytoplasmic tail of rhodopsin to reduce its function, but not decreasing rhodopsin expression levels, prevented rod degeneration in both kif3a and kif3b mutants. Of note, overexpression of full-length rhodopsin or its cytoplasmic tail domain, but not of rhodopsin lacking the cytoplasmic tail, exacerbated rod degeneration in kif3a mutants, implying an important role of the cytoplasmic tail in rod degeneration. Finally, we showed that the cytoplasmic tail of rhodopsin might trigger rod degeneration through activating the downstream calcium signaling pathway, as drug treatment with inhibitors of intracellular calcium release prevented rod degeneration in kif3a mutants. Our results demonstrate a previously unknown function of the rhodopsin cytoplasmic domain during opsin-triggered photoreceptor degeneration and may open up new avenues for managing this disease.
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Affiliation(s)
- Dong Feng
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Zhe Chen
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Kuang Yang
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Shanshan Miao
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Bolin Xu
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Yunsi Kang
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Haibo Xie
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Chengtian Zhao
- From the Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China, .,the Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China, and.,the Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
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20
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Vishnivetskiy SA, Lee RJ, Zhou XE, Franz A, Xu Q, Xu HE, Gurevich VV. Functional role of the three conserved cysteines in the N domain of visual arrestin-1. J Biol Chem 2017; 292:12496-12502. [PMID: 28536260 DOI: 10.1074/jbc.m117.790386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/22/2017] [Indexed: 11/06/2022] Open
Abstract
Arrestins specifically bind active and phosphorylated forms of their cognate G protein-coupled receptors, blocking G protein coupling and often redirecting the signaling to alternative pathways. High-affinity receptor binding is accompanied by two major structural changes in arrestin: release of the C-tail and rotation of the two domains relative to each other. The first requires detachment of the arrestin C-tail from the body of the molecule, whereas the second requires disruption of the network of charge-charge interactions at the interdomain interface, termed the polar core. These events can be facilitated by mutations destabilizing the polar core or the anchoring of the C-tail that yield "preactivated" arrestins that bind phosphorylated and unphosphorylated receptors with high affinity. Here we explored the functional role in arrestin activation of the three native cysteines in the N domain, which are conserved in all arrestin subtypes. Using visual arrestin-1 and rhodopsin as a model, we found that substitution of these cysteines with serine, alanine, or valine virtually eliminates the effects of the activating polar core mutations on the binding to unphosphorylated rhodopsin while only slightly reducing the effects of the C-tail mutations. Thus, these three conserved cysteines play a role in the domain rotation but not in the C-tail release.
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Affiliation(s)
| | - Regina J Lee
- Vanderbilt University, Nashville, Tennessee 37232
| | - X Edward Zhou
- VARI-SIMM Center, Center for Structure and Function of Drug Targets, Chinese Academy of Sciences Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | | | - Qiuyi Xu
- Vanderbilt University, Nashville, Tennessee 37232
| | - H Eric Xu
- VARI-SIMM Center, Center for Structure and Function of Drug Targets, Chinese Academy of Sciences Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, Michigan 49503
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21
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Differential manipulation of arrestin-3 binding to basal and agonist-activated G protein-coupled receptors. Cell Signal 2017; 36:98-107. [PMID: 28461104 DOI: 10.1016/j.cellsig.2017.04.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 04/11/2017] [Accepted: 04/26/2017] [Indexed: 12/21/2022]
Abstract
Non-visual arrestins interact with hundreds of different G protein-coupled receptors (GPCRs). Here we show that by introducing mutations into elements that directly bind receptors, the specificity of arrestin-3 can be altered. Several mutations in the two parts of the central "crest" of the arrestin molecule, middle-loop and C-loop, enhanced or reduced arrestin-3 interactions with several GPCRs in receptor subtype and functional state-specific manner. For example, the Lys139Ile substitution in the middle-loop dramatically enhanced the binding to inactive M2 muscarinic receptor, so that agonist activation of the M2 did not further increase arrestin-3 binding. Thus, the Lys139Ile mutation made arrestin-3 essentially an activation-independent binding partner of M2, whereas its interactions with other receptors, including the β2-adrenergic receptor and the D1 and D2 dopamine receptors, retained normal activation dependence. In contrast, the Ala248Val mutation enhanced agonist-induced arrestin-3 binding to the β2-adrenergic and D2 dopamine receptors, while reducing its interaction with the D1 dopamine receptor. These mutations represent the first example of altering arrestin specificity via enhancement of the arrestin-receptor interactions rather than selective reduction of the binding to certain subtypes.
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22
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Gurevich VV, Gurevich EV. Analyzing the roles of multi-functional proteins in cells: The case of arrestins and GRKs. Crit Rev Biochem Mol Biol 2016; 50:440-52. [PMID: 26453028 DOI: 10.3109/10409238.2015.1067185] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Most proteins have multiple functions. Obviously, conventional methods of manipulating the level of the protein of interest in the cell, such as over-expression, knockout or knockdown, affect all of its functions simultaneously. The key advantage of these methods is that over-expression, knockout or knockdown does not require any knowledge of the molecular mechanisms of the function(s) of the protein of interest. The disadvantage is that these approaches are inadequate to elucidate the role of an individual function of the protein in a particular cellular process. An alternative is the use of re-engineered proteins, in which a single function is eliminated or enhanced. The use of mono-functional elements of a multi-functional protein can also yield cleaner answers. This approach requires detailed knowledge of the structural basis of each function of the protein in question. Thus, a lot of preliminary structure-function work is necessary to make it possible. However, when this information is available, replacing the protein of interest with a mutant in which individual functions are modified can shed light on the biological role of those particular functions. Here, we illustrate this point using the example of protein kinases, most of which have additional non-enzymatic functions, as well as arrestins, known multi-functional signaling regulators in the cell.
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Affiliation(s)
| | - Eugenia V Gurevich
- a Department of Pharmacology , Vanderbilt University , Nashville , TN , USA
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23
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Gurevich EV, Gurevich VV. Beyond traditional pharmacology: new tools and approaches. Br J Pharmacol 2015; 172:3229-41. [PMID: 25572005 DOI: 10.1111/bph.13066] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/24/2014] [Accepted: 01/02/2015] [Indexed: 12/14/2022] Open
Abstract
Traditional pharmacology is defined as the science that deals with drugs and their actions. While small molecule drugs have clear advantages, there are many cases where they have proved to be ineffective, prone to unacceptable side effects, or where due to a particular disease aetiology they cannot possibly be effective. A dominant feature of the small molecule drugs is their single mindedness: they provide either continuous inhibition or continuous activation of the target. Because of that, these drugs tend to engage compensatory mechanisms leading to drug tolerance, drug resistance or, in some cases, sensitization and consequent loss of therapeutic efficacy over time and/or unwanted side effects. Here we discuss new and emerging therapeutic tools and approaches that have potential for treating the majority of disorders for which small molecules are either failing or cannot be developed. These new tools include biologics, such as recombinant hormones and antibodies, as well as approaches involving gene transfer (gene therapy and genome editing) and the introduction of specially designed self-replicating cells. It is clear that no single method is going to be a 'silver bullet', but collectively, these novel approaches hold promise for curing practically every disorder.
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Affiliation(s)
- E V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - V V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
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24
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Stoy H, Gurevich VV. How genetic errors in GPCRs affect their function: Possible therapeutic strategies. Genes Dis 2015; 2:108-132. [PMID: 26229975 PMCID: PMC4516391 DOI: 10.1016/j.gendis.2015.02.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/07/2015] [Indexed: 01/14/2023] Open
Abstract
Activating and inactivating mutations in numerous human G protein-coupled receptors (GPCRs) are associated with a wide range of disease phenotypes. Here we use several class A GPCRs with a particularly large set of identified disease-associated mutations, many of which were biochemically characterized, along with known GPCR structures and current models of GPCR activation, to understand the molecular mechanisms yielding pathological phenotypes. Based on this mechanistic understanding we also propose different therapeutic approaches, both conventional, using small molecule ligands, and novel, involving gene therapy.
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25
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Kim DK, Yun Y, Kim HR, Seo MD, Chung KY. Different conformational dynamics of various active states of β-arrestin1 analyzed by hydrogen/deuterium exchange mass spectrometry. J Struct Biol 2015; 190:250-9. [DOI: 10.1016/j.jsb.2015.04.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/26/2015] [Accepted: 04/07/2015] [Indexed: 01/14/2023]
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26
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GPCR structure, function, drug discovery and crystallography: report from Academia-Industry International Conference (UK Royal Society) Chicheley Hall, 1-2 September 2014. Naunyn Schmiedebergs Arch Pharmacol 2015; 388:883-903. [PMID: 25772061 PMCID: PMC4495723 DOI: 10.1007/s00210-015-1111-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 02/24/2015] [Indexed: 01/14/2023]
Abstract
G-protein coupled receptors (GPCRs) are the targets of over half of all prescribed drugs today. The UniProt database has records for about 800 proteins classified as GPCRs, but drugs have only been developed against 50 of these. Thus, there is huge potential in terms of the number of targets for new therapies to be designed. Several breakthroughs in GPCRs biased pharmacology, structural biology, modelling and scoring have resulted in a resurgence of interest in GPCRs as drug targets. Therefore, an international conference, sponsored by the Royal Society, with world-renowned researchers from industry and academia was recently held to discuss recent progress and highlight key areas of future research needed to accelerate GPCR drug discovery. Several key points emerged. Firstly, structures for all three major classes of GPCRs have now been solved and there is increasing coverage across the GPCR phylogenetic tree. This is likely to be substantially enhanced with data from x-ray free electron sources as they move beyond proof of concept. Secondly, the concept of biased signalling or functional selectivity is likely to be prevalent in many GPCRs, and this presents exciting new opportunities for selectivity and the control of side effects, especially when combined with increasing data regarding allosteric modulation. Thirdly, there will almost certainly be some GPCRs that will remain difficult targets because they exhibit complex ligand dependencies and have many metastable states rendering them difficult to resolve by crystallographic methods. Subtle effects within the packing of the transmembrane helices are likely to mask and contribute to this aspect, which may play a role in species dependent behaviour. This is particularly important because it has ramifications for how we interpret pre-clinical data. In summary, collaborative efforts between industry and academia have delivered significant progress in terms of structure and understanding of GPCRs and will be essential for resolving problems associated with the more difficult targets in the future.
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27
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Vishnivetskiy SA, Zhan X, Chen Q, Iverson TM, Gurevich VV. Arrestin expression in E. coli and purification. CURRENT PROTOCOLS IN PHARMACOLOGY 2014; 67:2.11.1-2.11.19. [PMID: 25446290 PMCID: PMC4260927 DOI: 10.1002/0471141755.ph0211s67] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Purified arrestin proteins are necessary for biochemical, biophysical, and crystallographic studies of these versatile regulators of cell signaling. Described herein is a basic protocol for arrestin expression in E. coli and purification of the tag-free wild-type and mutant arrestins. The method includes ammonium sulfate precipitation of arrestins from cell lysates, followed by heparin-Sepharose chromatography. Depending on the arrestin type and/or mutations, the next step is Q-Sepharose or SP-Sepharose chromatography. In many cases the nonbinding column is used as a filter to bind contaminants without retaining arrestin. In some cases both chromatographic steps must be performed sequentially to achieve high purity. Purified arrestins can be concentrated up to 10 mg/ml, remain fully functional, and withstand several cycles of freezing and thawing, provided that overall salt concentration is maintained at or above physiological levels.
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Affiliation(s)
| | - Xuanzhi Zhan
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Qiuyan Chen
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Tina M Iverson
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
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28
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Abstract
Virtually all currently used therapeutic agents are small molecules, largely because the development and delivery of small molecule drugs is relatively straightforward. Small molecules have serious limitations: drugs of this type can be fairly good enzyme inhibitors, receptor ligands, or allosteric modulators. However, most cellular functions are mediated by protein interactions with other proteins, and targeting protein-protein interactions by small molecules presents challenges that are unlikely to be overcome with these compounds as the only tools. Recent advances in gene delivery techniques and characterization of cell type-specific promoters open the prospect of using reengineered signaling-biased proteins as next-generation therapeutics. The first steps in targeted engineering of proteins with desired functional characteristics look very promising. As quintessential scaffolds that act strictly via interactions with other proteins in the cell, arrestins represent a perfect model for the development of these novel therapeutic agents with enormous potential: custom-designed signaling proteins will allow us to tell the cell what to do and when to do it in a way it cannot disobey.
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29
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Zhan X, Perez A, Gimenez LE, Vishnivetskiy SA, Gurevich VV. Arrestin-3 binds the MAP kinase JNK3α2 via multiple sites on both domains. Cell Signal 2014; 26:766-76. [PMID: 24412749 PMCID: PMC3936466 DOI: 10.1016/j.cellsig.2014.01.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 12/18/2013] [Accepted: 01/02/2014] [Indexed: 01/14/2023]
Abstract
Although arrestins bind dozens of non-receptor partners, the interaction sites for most signaling proteins remain unknown. Here we report the identification of arrestin-3 elements involved in binding MAP kinase JNK3α2. Using purified JNK3α2 and MBP fusions containing separated arrestin-3 domains and peptides exposed on the non-receptor-binding surface of arrestin-3 we showed that both domains bind JNK3α2 and identified one element on the N-domain and two on the C-domain that directly interact with JNK3α2. Using in vitro competition we confirmed that JNK3α2 engages identified N-domain element and one of the C-domain peptides in the full-length arrestin-3. The 25-amino acid N-domain element has the highest affinity for JNK3α2, suggesting that it is the key site for JNK3α2 docking. The identification of elements involved in protein-protein interactions paves the way to targeted redesign of signaling proteins to modulate cell signaling in desired ways. The tools and methods developed here to elucidate the molecular mechanism of arrestin-3 interactions with JNK3α2 are suitable for mapping of arrestin-3 sites involved in interactions with other partners.
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Affiliation(s)
- Xuanzhi Zhan
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Alejandro Perez
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Luis E Gimenez
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | | | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.
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30
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Gurevich VV, Song X, Vishnivetskiy SA, Gurevich EV. Enhanced phosphorylation-independent arrestins and gene therapy. Handb Exp Pharmacol 2014; 219:133-152. [PMID: 24292828 PMCID: PMC4516159 DOI: 10.1007/978-3-642-41199-1_7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A variety of heritable and acquired disorders is associated with excessive signaling by mutant or overstimulated GPCRs. Since any conceivable treatment of diseases caused by gain-of-function mutations requires gene transfer, one possible approach is functional compensation. Several structurally distinct forms of enhanced arrestins that bind phosphorylated and even non-phosphorylated active GPCRs with much higher affinity than parental wild-type proteins have the ability to dampen the signaling by hyperactive GPCR, pushing the balance closer to normal. In vivo this approach was so far tested only in rod photoreceptors deficient in rhodopsin phosphorylation, where enhanced arrestin improved the morphology and light sensitivity of rods, prolonged their survival, and accelerated photoresponse recovery. Considering that rods harbor the fastest, as well as the most demanding and sensitive GPCR-driven signaling cascade, even partial success of functional compensation of defect in rhodopsin phosphorylation by enhanced arrestin demonstrates the feasibility of this strategy and its therapeutic potential.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Avenue, Nashville, TN, 37232, USA,
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31
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Gimenez LE, Vishnivetskiy SA, Gurevich VV. Targeting individual GPCRs with redesigned nonvisual arrestins. Handb Exp Pharmacol 2014; 219:153-70. [PMID: 24292829 DOI: 10.1007/978-3-642-41199-1_8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Numerous human diseases are caused by excessive signaling of mutant G protein-coupled receptors (GPCRs) or receptors that are overstimulated due to upstream signaling imbalances. The feasibility of functional compensation by arrestins with enhanced ability to quench receptor signaling was recently tested in the visual system. The results showed that even in this extremely demanding situation of rods that have no ability to phosphorylate rhodopsin, enhanced arrestin improved rod morphology, light sensitivity, survival, and accelerated photoresponse recovery. Structurally distinct enhanced mutants of arrestins that bind phosphorylated and non-phosphorylated active GPCRs with much higher affinity than parental wild-type (WT) proteins have been constructed. These "super-arrestins" are likely to have the power to dampen the signaling by hyperactive GPCRs. However, most cells express 5-20 GPCR subtypes, only one of which would be overactive, while nonvisual arrestins are remarkably promiscuous, binding hundreds of different GPCRs. Thus, to be therapeutically useful, enhanced versions of nonvisual arrestins must be made fairly specific for particular receptors. Recent identification of very few arrestin residues as key receptor discriminators paves the way to the construction of receptor subtype-specific nonvisual arrestins.
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Affiliation(s)
- Luis E Gimenez
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Avenue, Nashville, TN, 37232, USA,
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32
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Abstract
Programmed cell death (apoptosis) is a coordinated set of events eventually leading to the massive activation of specialized proteases (caspases) that cleave numerous substrates, orchestrating fairly uniform biochemical changes than culminate in cellular suicide. Apoptosis can be triggered by a variety of stimuli, from external signals or growth factor withdrawal to intracellular conditions, such as DNA damage or ER stress. Arrestins regulate many signaling cascades involved in life-or-death decisions in the cell, so it is hardly surprising that numerous reports document the effects of ubiquitous nonvisual arrestins on apoptosis under various conditions. Although these findings hardly constitute a coherent picture, with the same arrestin subtypes, sometimes via the same signaling pathways, reported to promote or inhibit cell death, this might reflect real differences in pro- and antiapoptotic signaling in different cells under a variety of conditions. Recent finding suggests that one of the nonvisual subtypes, arrestin-2, is specifically cleaved by caspases. Generated fragment actively participates in the core mechanism of apoptosis: it assists another product of caspase activity, tBID, in releasing cytochrome C from mitochondria. This is the point of no return in committing vertebrate cells to death, and the aspartate where caspases cleave arrestin-2 is evolutionary conserved in vertebrate, but not in invertebrate arrestins. In contrast to wild-type arrestin-2, its caspase-resistant mutant does not facilitate cell death.
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Affiliation(s)
- Seunghyi Kook
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Ave, Nashville, TN, 37232, USA
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Chen Q, Zhuo Y, Kim M, Hanson SM, Francis DJ, Vishnivetskiy SA, Altenbach C, Klug CS, Hubbell WL, Gurevich VV. Self-association of arrestin family members. Handb Exp Pharmacol 2014; 219:205-23. [PMID: 24292832 DOI: 10.1007/978-3-642-41199-1_11] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mammals express four arrestin subtypes, three of which have been shown to self-associate. Cone photoreceptor-specific arrestin-4 is the only one that is a constitutive monomer. Visual arrestin-1 forms tetramers both in crystal and in solution, but the shape of its physiologically relevant solution tetramer is very different from that in the crystal. The biological role of the self-association of arrestin-1, expressed at very high levels in rod and cone photoreceptors, appears to be protective, reducing the concentration of cytotoxic monomers. The two nonvisual arrestin subtypes are highly homologous, and self-association of both is facilitated by IP6, yet they form dramatically different oligomers. Arrestin-2 apparently self-associates into "infinite" chains, very similar to those observed in IP6-soaked crystals, where IP6 connects the concave sides of the N- and C-domains of adjacent protomers. In contrast, arrestin-3 only forms dimers, in which IP6 likely connects the C-domains of two arrestin-3 molecules. Thus, each of the three self-associating arrestins does it in its own way, forming three different types of oligomers. The physiological role of the oligomerization of arrestin-1 and both nonvisual arrestins might be quite different, and in each case it remains to be definitively elucidated.
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Affiliation(s)
- Qiuyan Chen
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Avenue, Nashville, TN, 37232, USA
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34
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Gurevich VV, Gurevich EV. Extensive shape shifting underlies functional versatility of arrestins. Curr Opin Cell Biol 2013; 27:1-9. [PMID: 24680424 DOI: 10.1016/j.ceb.2013.10.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 10/20/2013] [Accepted: 10/23/2013] [Indexed: 12/24/2022]
Abstract
Among four vertebrate arrestins, only two are ubiquitously expressed. Arrestins specifically bind active phosphorylated G protein-coupled receptors (GPCRs), thereby precluding further G protein activation. Recent discoveries suggest that the formation of the arrestin-receptor complex initiates the second round of signaling with comparable biological importance. Despite having virtually no recognizable sequence motifs known to mediate protein-protein interactions, arrestins bind a surprising variety of signaling proteins with mind-boggling range of functional consequences. High conformational flexibility allows arrestins to show many distinct 'faces' to the world, which allows these relatively small ∼45kDa proteins to bind various partners under different physiological conditions, organizing multi-protein signaling complexes and localizing them to distinct subcellular compartments.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
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35
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Vishnivetskiy SA, Ostermaier MK, Singhal A, Panneels V, Homan KT, Glukhova A, Sligar SG, Tesmer JJG, Schertler GF, Standfuss J, Gurevich VV. Constitutively active rhodopsin mutants causing night blindness are effectively phosphorylated by GRKs but differ in arrestin-1 binding. Cell Signal 2013; 25:2155-62. [PMID: 23872075 PMCID: PMC3774132 DOI: 10.1016/j.cellsig.2013.07.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 07/11/2013] [Indexed: 11/24/2022]
Abstract
The effects of activating mutations associated with night blindness on the stoichiometry of rhodopsin interactions with G protein-coupled receptor kinase 1 (GRK1) and arrestin-1 have not been reported. Here we show that the monomeric form of WT rhodopsin and its constitutively active mutants M257Y, G90D, and T94I, reconstituted into HDL particles are effectively phosphorylated by GRK1, as well as two more ubiquitously expressed subtypes, GRK2 and GRK5. All versions of arrestin-1 tested (WT, pre-activated, and constitutively monomeric mutants) bind to monomeric rhodopsin and show the same selectivity for different functional forms of rhodopsin as in native disc membranes. Rhodopsin phosphorylation by GRK1 and GRK2 promotes arrestin-1 binding to a comparable extent, whereas similar phosphorylation by GRK5 is less effective, suggesting that not all phosphorylation sites on rhodopsin are equivalent in promoting arrestin-1 binding. The binding of WT arrestin-1 to phospho-opsin is comparable to the binding to its preferred target, P-Rh*, suggesting that in photoreceptors arrestin-1 only dissociates after opsin regeneration with 11-cis-retinal, which converts phospho-opsin into inactive phospho-rhodopsin that has lower affinity for arrestin-1. Reduced binding of arrestin-1 to the phospho-opsin form of G90D mutant likely contributes to night blindness caused by this mutation in humans.
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Affiliation(s)
| | - Martin K. Ostermaier
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen 5232, Switzerland
| | - Ankita Singhal
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen 5232, Switzerland
| | - Valerie Panneels
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen 5232, Switzerland
| | - Kristoff T. Homan
- Life Sciences Institute, Departments of Pharmacology and Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-2216, USA
| | - Alisa Glukhova
- Life Sciences Institute, Departments of Pharmacology and Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-2216, USA
| | - Stephen G. Sligar
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - John J. G. Tesmer
- Life Sciences Institute, Departments of Pharmacology and Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-2216, USA
| | - Gebhard F.X. Schertler
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen 5232, Switzerland
- Department of Biology, ETH Zurich, Zurich, 8093, Switzerland
| | - Joerg Standfuss
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen 5232, Switzerland
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Song X, Seo J, Baameur F, Vishnivetskiy SA, Chen Q, Kook S, Kim M, Brooks EK, Altenbach C, Hong Y, Hanson SM, Palazzo MC, Chen J, Hubbell WL, Gurevich EV, Gurevich VV. Rapid degeneration of rod photoreceptors expressing self-association-deficient arrestin-1 mutant. Cell Signal 2013; 25:2613-24. [PMID: 24012956 DOI: 10.1016/j.cellsig.2013.08.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 08/23/2013] [Indexed: 10/26/2022]
Abstract
Arrestin-1 binds light-activated phosphorhodopsin and ensures timely signal shutoff. We show that high transgenic expression of an arrestin-1 mutant with enhanced rhodopsin binding and impaired oligomerization causes apoptotic rod death in mice. Dark rearing does not prevent mutant-induced cell death, ruling out the role of arrestin complexes with light-activated rhodopsin. Similar expression of WT arrestin-1 that robustly oligomerizes, which leads to only modest increase in the monomer concentration, does not affect rod survival. Moreover, WT arrestin-1 co-expressed with the mutant delays retinal degeneration. Thus, arrestin-1 mutant directly affects cell survival via binding partner(s) other than light-activated rhodopsin. Due to impaired self-association of the mutant its high expression dramatically increases the concentration of the monomer. The data suggest that monomeric arrestin-1 is cytotoxic and WT arrestin-1 protects rods by forming mixed oligomers with the mutant and/or competing with it for the binding to non-receptor partners. Thus, arrestin-1 self-association likely serves to keep low concentration of the toxic monomer. The reduction of the concentration of harmful monomer is an earlier unappreciated biological function of protein oligomerization.
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Affiliation(s)
- Xiufeng Song
- Vanderbilt University, Nashville, TN 37232, United States
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Vishnivetskiy SA, Baameur F, Findley KR, Gurevich VV. Critical role of the central 139-loop in stability and binding selectivity of arrestin-1. J Biol Chem 2013; 288:11741-50. [PMID: 23476014 DOI: 10.1074/jbc.m113.450031] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Arrestin-1 selectively binds active phosphorylated rhodopsin (P-Rh*), demonstrating much lower affinity for inactive phosphorylated (P-Rh) and unphosphorylated active (Rh*) forms. Receptor interaction induces significant conformational changes in arrestin-1, which include large movement of the previously neglected 139-loop in the center of the receptor binding surface, away from the incoming receptor. To elucidate the functional role of this loop, in mouse arrestin-1 we introduced deletions of variable lengths and made several substitutions of Lys-142 in it and Asp-72 in the adjacent loop. Several mutants with perturbations in the 139-loop demonstrate increased binding to P-Rh*, dark P-Rh, Rh*, and phospho-opsin. Enhanced binding of arrestin-1 mutants to non-preferred forms of rhodopsin correlates with decreased thermal stability. The 139-loop perturbations increase P-Rh* binding of arrestin-1 at low temperatures and further change its binding profile on the background of 3A mutant, where the C-tail is detached from the body of the molecule by triple alanine substitution. Thus, the 139-loop stabilizes basal conformation of arrestin-1 and acts as a brake, preventing its binding to non-preferred forms of rhodopsin. Conservation of this loop in other subtypes suggests that it has the same function in all members of the arrestin family.
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38
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Gurevich VV, Gurevich EV. Structural determinants of arrestin functions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:57-92. [PMID: 23764050 PMCID: PMC4514030 DOI: 10.1016/b978-0-12-394440-5.00003-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Arrestins are a small protein family with only four members in mammals. Arrestins demonstrate an amazing versatility, interacting with hundreds of different G protein-coupled receptor (GPCR) subtypes, numerous nonreceptor signaling proteins, and components of the internalization machinery, as well as cytoskeletal elements, including regular microtubules and centrosomes. Here, we focus on the structural determinants that mediate various arrestin functions. The receptor-binding elements in arrestins were mapped fairly comprehensively, which set the stage for the construction of mutants targeting particular GPCRs. The elements engaged by other binding partners are only now being elucidated and in most cases we have more questions than answers. Interestingly, even very limited and imprecise identification of structural requirements for the interaction with very few other proteins has enabled the development of signaling-biased arrestin mutants. More comprehensive understanding of the structural underpinning of different arrestin functions will pave the way for the construction of arrestins that can link the receptor we want to the signaling pathway of our choosing.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
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39
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Involvement of distinct arrestin-1 elements in binding to different functional forms of rhodopsin. Proc Natl Acad Sci U S A 2012; 110:942-7. [PMID: 23277586 DOI: 10.1073/pnas.1215176110] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Solution NMR spectroscopy of labeled arrestin-1 was used to explore its interactions with dark-state phosphorylated rhodopsin (P-Rh), phosphorylated opsin (P-opsin), unphosphorylated light-activated rhodopsin (Rh*), and phosphorylated light-activated rhodopsin (P-Rh*). Distinct sets of arrestin-1 elements were seen to be engaged by Rh* and inactive P-Rh, which induced conformational changes that differed from those triggered by binding of P-Rh*. Although arrestin-1 affinity for Rh* was seen to be low (K(D) > 150 μM), its affinity for P-Rh (K(D) ~80 μM) was comparable to the concentration of active monomeric arrestin-1 in the outer segment, suggesting that P-Rh generated by high-gain phosphorylation is occupied by arrestin-1 under physiological conditions and will not signal upon photo-activation. Arrestin-1 was seen to bind P-Rh* and P-opsin with fairly high affinity (K(D) of~50 and 800 nM, respectively), implying that arrestin-1 dissociation is triggered only upon P-opsin regeneration with 11-cis-retinal, precluding noise generated by opsin activity. Based on their observed affinity for arrestin-1, P-opsin and inactive P-Rh very likely affect the physiological monomer-dimer-tetramer equilibrium of arrestin-1, and should therefore be taken into account when modeling photoreceptor function. The data also suggested that complex formation with either P-Rh* or P-opsin results in a global transition in the conformation of arrestin-1, possibly to a dynamic molten globule-like structure. We hypothesize that this transition contributes to the mechanism that triggers preferential interactions of several signaling proteins with receptor-activated arrestins.
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40
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Vishnivetskiy SA, Chen Q, Palazzo MC, Brooks EK, Altenbach C, Iverson TM, Hubbell WL, Gurevich VV. Engineering visual arrestin-1 with special functional characteristics. J Biol Chem 2012; 288:3394-405. [PMID: 23250748 DOI: 10.1074/jbc.m112.445437] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Arrestin-1 preferentially binds active phosphorylated rhodopsin. Previously, a mutant with enhanced binding to unphosphorylated active rhodopsin (Rh*) was shown to partially compensate for lack of rhodopsin phosphorylation in vivo. Here we showed that reengineering of the receptor binding surface of arrestin-1 further improves the binding to Rh* while preserving protein stability. In mammals, arrestin-1 readily self-associates at physiological concentrations. The biological role of this phenomenon can only be elucidated by replacing wild type arrestin-1 in living animals with a non-oligomerizing mutant retaining all other functions. We demonstrate that constitutively monomeric forms of arrestin-1 are sufficiently stable for in vivo expression. We also tested the idea that individual functions of arrestin-1 can be independently manipulated to generate mutants with the desired combinations of functional characteristics. Here we showed that this approach is feasible; stable forms of arrestin-1 with high Rh* binding can be generated with or without the ability to self-associate. These novel molecular tools open the possibility of testing of the biological role of arrestin-1 self-association and pave the way to elucidation of full potential of compensational approach to gene therapy of gain-of-function receptor mutations.
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41
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Gross OP, Pugh EN, Burns ME. Calcium feedback to cGMP synthesis strongly attenuates single-photon responses driven by long rhodopsin lifetimes. Neuron 2012; 76:370-82. [PMID: 23083739 PMCID: PMC3594095 DOI: 10.1016/j.neuron.2012.07.029] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2012] [Indexed: 11/26/2022]
Abstract
Rod photoreceptors generate amplified, reproducible responses to single photons via a G protein signaling cascade. Surprisingly, genetic perturbations that dramatically alter the deactivation of the principal signal amplifier, the GPCR rhodopsin (R∗), do not much alter the amplitude of single-photon responses (SPRs). These same perturbations, when crossed into a line lacking calcium feedback regulation of cGMP synthesis, produced much larger alterations in SPR amplitudes. Analysis of SPRs from rods with and without feedback reveal that the consequences of trial-to-trial fluctuations in R∗ lifetime in normal rods are also dampened by feedback regulation of cGMP synthesis. Thus, calcium feedback trumps the mechanisms of R∗ deactivation in determining the SPR amplitude, attenuating responses arising from longer R∗ lifetimes to a greater extent than those arising from shorter ones. As a result, rod SPRs achieve a more stereotyped amplitude, a characteristic considered important for reliable transmission through the visual system.
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Affiliation(s)
- Owen P. Gross
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
| | - Edward N. Pugh
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, CA 95618, USA
- Department of Cell Biology and Human Anatomy, University of California, Davis, Davis, CA 95618, USA
| | - Marie E. Burns
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
- Department of Cell Biology and Human Anatomy, University of California, Davis, Davis, CA 95618, USA
- Center for Neuroscience and Department of Ophthalmology & Vision Science, University of California, Davis, Davis, CA 95618, USA
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42
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Gurevich VV, Gurevich EV. Synthetic biology with surgical precision: targeted reengineering of signaling proteins. Cell Signal 2012; 24:1899-908. [PMID: 22664341 PMCID: PMC3404258 DOI: 10.1016/j.cellsig.2012.05.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 05/14/2012] [Indexed: 01/14/2023]
Abstract
The complexity of living systems exceeds everything else studied by natural sciences. Sophisticated networks of intimately intertwined signaling pathways coordinate cellular functions. Clear understanding how the integration of multiple inputs produces coherent behavior is one of the major challenges of cell biology. Integration via perfectly timed highly regulated protein-protein interactions and precise targeting of the "output" proteins to particular substrates is emerging as a common theme of signaling regulation. This often involves specialized scaffolding proteins, whose key function is to ensure that correct partners come together in an appropriate place at the right time. Defective or faulty signaling underlies many congenital and acquired human disorders. Several pioneering studies showed that ectopic expression of existing proteins or their elements can restore functions destroyed by mutations or normalize the signaling pushed out of balance by disease and/or current small molecule-based therapy. Several recent studies show that proteins with new functional modalities can be generated by mixing and matching existing domains, or via functional recalibration and fine-tuning of existing proteins by precisely targeted mutations. Using arrestins as an example, we describe how manipulation of individual functions yields signaling-biased proteins. Creative protein redesign generates novel tools valuable for unraveling the intricacies of cell biology. Engineered proteins with specific functional changes also have huge therapeutic potential in disorders associated with inherited or acquired signaling errors.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.
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43
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Gimenez LE, Vishnivetskiy SA, Baameur F, Gurevich VV. Manipulation of very few receptor discriminator residues greatly enhances receptor specificity of non-visual arrestins. J Biol Chem 2012; 287:29495-505. [PMID: 22787152 DOI: 10.1074/jbc.m112.366674] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Based on the identification of residues that determine receptor selectivity of arrestins and the analysis of the evolution in the arrestin family, we introduced 10 mutations of "receptor discriminator" residues in arrestin-3. The recruitment of these mutants to M2 muscarinic (M2R), D1 (D1R) and D2 (D2R) dopamine, and β(2)-adrenergic receptors (β(2)AR) was assessed using bioluminescence resonance energy transfer-based assays in cells. Seven of 10 mutations differentially affected arrestin-3 binding to individual receptors. D260K and Q262P reduced the binding to β(2)AR, much more than to other receptors. The combination D260K/Q262P virtually eliminated β(2)AR binding while preserving the interactions with M2R, D1R, and D2R. Conversely, Y239T enhanced arrestin-3 binding to β(2)AR and reduced the binding to M2R, D1R, and D2R, whereas Q256Y selectively reduced recruitment to D2R. The Y239T/Q256Y combination virtually eliminated the binding to D2R and reduced the binding to β(2)AR and M2R, yielding a mutant with high selectivity for D1R. Eleven of 12 mutations significantly changed the binding to light-activated phosphorhodopsin. Thus, manipulation of key residues on the receptor-binding surface modifies receptor preference, enabling the construction of non-visual arrestins specific for particular receptor subtypes. These findings pave the way to the construction of signaling-biased arrestins targeting the receptor of choice for research or therapeutic purposes.
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Affiliation(s)
- Luis E Gimenez
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
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44
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Breitman M, Kook S, Gimenez LE, Lizama BN, Palazzo MC, Gurevich EV, Gurevich VV. Silent scaffolds: inhibition OF c-Jun N-terminal kinase 3 activity in cell by dominant-negative arrestin-3 mutant. J Biol Chem 2012; 287:19653-64. [PMID: 22523077 DOI: 10.1074/jbc.m112.358192] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We established a new in vivo arrestin-3-JNK3 interaction assay based on bioluminescence resonance energy transfer (BRET) between JNK3-luciferase and Venus-arrestins. We tested the ability of WT arrestin-3 and its 3A mutant that readily binds β2-adrenergic receptors as well as two mutants impaired in receptor binding, Δ7 and KNC, to directly bind JNK3 and to promote JNK3 phosphorylation in cells. Both receptor binding-deficient mutants interact with JNK3 significantly better than WT and 3A arrestin-3. WT arrestin-3 and Δ7 mutant robustly promoted JNK3 activation, whereas 3A and KNC mutants did not. Thus, receptor binding, JNK3 interaction, and JNK3 activation are three distinct arrestin functions. We found that the KNC mutant, which tightly binds ASK1, MKK4, and JNK3 without facilitating JNK3 phosphorylation, has a dominant-negative effect, competitively decreasing JNK activation by WT arrestin-3. Thus, KNC is a silent scaffold, a novel type of molecular tool for the suppression of MAPK signaling in living cells.
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Affiliation(s)
- Maya Breitman
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, USA
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45
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Coffa S, Breitman M, Hanson SM, Callaway K, Kook S, Dalby KN, Gurevich VV. The effect of arrestin conformation on the recruitment of c-Raf1, MEK1, and ERK1/2 activation. PLoS One 2011; 6:e28723. [PMID: 22174878 PMCID: PMC3236217 DOI: 10.1371/journal.pone.0028723] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 11/14/2011] [Indexed: 01/27/2023] Open
Abstract
Arrestins are multifunctional signaling adaptors originally discovered as proteins that “arrest” G protein activation by G protein-coupled receptors (GPCRs). Recently GPCR complexes with arrestins have been proposed to activate G protein-independent signaling pathways. In particular, arrestin-dependent activation of extracellular signal-regulated kinase 1/2 (ERK1/2) has been demonstrated. Here we have performed in vitro binding assays with pure proteins to demonstrate for the first time that ERK2 directly binds free arrestin-2 and -3, as well as receptor-associated arrestins-1, -2, and -3. In addition, we showed that in COS-7 cells arrestin-2 and -3 association with β2-adrenergic receptor (β2AR) significantly enhanced ERK2 binding, but showed little effect on arrestin interactions with the upstream kinases c-Raf1 and MEK1. Arrestins exist in three conformational states: free, receptor-bound, and microtubule-associated. Using conformationally biased arrestin mutants we found that ERK2 preferentially binds two of these: the “constitutively inactive” arrestin-Δ7 mimicking microtubule-bound state and arrestin-3A, a mimic of the receptor-bound conformation. Both rescue arrestin-mediated ERK1/2/activation in arrestin-2/3 double knockout fibroblasts. We also found that arrestin-2-c-Raf1 interaction is enhanced by receptor binding, whereas arrestin-3-c-Raf1 interaction is not.
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Affiliation(s)
- Sergio Coffa
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Maya Breitman
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Susan M. Hanson
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kari Callaway
- Division of Medicinal Chemistry, The University of Texas at Austin, Austin, Texas, United States of America
| | - Seunghyi Kook
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kevin N. Dalby
- Division of Medicinal Chemistry, The University of Texas at Austin, Austin, Texas, United States of America
| | - Vsevolod V. Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
- * E-mail:
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46
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Gurevich EV, Tesmer JJG, Mushegian A, Gurevich VV. G protein-coupled receptor kinases: more than just kinases and not only for GPCRs. Pharmacol Ther 2011; 133:40-69. [PMID: 21903131 DOI: 10.1016/j.pharmthera.2011.08.001] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 08/01/2011] [Indexed: 12/24/2022]
Abstract
G protein-coupled receptor (GPCR) kinases (GRKs) are best known for their role in homologous desensitization of GPCRs. GRKs phosphorylate activated receptors and promote high affinity binding of arrestins, which precludes G protein coupling. GRKs have a multidomain structure, with the kinase domain inserted into a loop of a regulator of G protein signaling homology domain. Unlike many other kinases, GRKs do not need to be phosphorylated in their activation loop to achieve an activated state. Instead, they are directly activated by docking with active GPCRs. In this manner they are able to selectively phosphorylate Ser/Thr residues on only the activated form of the receptor, unlike related kinases such as protein kinase A. GRKs also phosphorylate a variety of non-GPCR substrates and regulate several signaling pathways via direct interactions with other proteins in a phosphorylation-independent manner. Multiple GRK subtypes are present in virtually every animal cell, with the highest expression levels found in neurons, with their extensive and complex signal regulation. Insufficient or excessive GRK activity was implicated in a variety of human disorders, ranging from heart failure to depression to Parkinson's disease. As key regulators of GPCR-dependent and -independent signaling pathways, GRKs are emerging drug targets and promising molecular tools for therapy. Targeted modulation of expression and/or of activity of several GRK isoforms for therapeutic purposes was recently validated in cardiac disorders and Parkinson's disease.
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Affiliation(s)
- Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Avenue, Preston Research Building, Rm. 454, Nashville, TN 37232, United States.
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47
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Gurevich VV, Hanson SM, Song X, Vishnivetskiy SA, Gurevich EV. The functional cycle of visual arrestins in photoreceptor cells. Prog Retin Eye Res 2011; 30:405-30. [PMID: 21824527 DOI: 10.1016/j.preteyeres.2011.07.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 07/20/2011] [Accepted: 07/21/2011] [Indexed: 01/14/2023]
Abstract
Visual arrestin-1 plays a key role in the rapid and reproducible shutoff of rhodopsin signaling. Its highly selective binding to light-activated phosphorylated rhodopsin is an integral part of the functional perfection of rod photoreceptors. Structure-function studies revealed key elements of the sophisticated molecular mechanism ensuring arrestin-1 selectivity and paved the way to the targeted manipulation of the arrestin-1 molecule to design mutants that can compensate for congenital defects in rhodopsin phosphorylation. Arrestin-1 self-association and light-dependent translocation in photoreceptor cells work together to keep a constant supply of active rhodopsin-binding arrestin-1 monomer in the outer segment. Recent discoveries of arrestin-1 interaction with other signaling proteins suggest that it is a much more versatile signaling regulator than previously thought, affecting the function of the synaptic terminals and rod survival. Elucidation of the fine molecular mechanisms of arrestin-1 interactions with rhodopsin and other binding partners is necessary for the comprehensive understanding of rod function and for devising novel molecular tools and therapeutic approaches to the treatment of visual disorders.
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Affiliation(s)
- Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, 2200 Pierce Ave, PRB, Rm 417D, Nashville, TN 37232, USA.
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Cleghorn WM, Tsakem EL, Song X, Vishnivetskiy SA, Seo J, Chen J, Gurevich EV, Gurevich VV. Progressive reduction of its expression in rods reveals two pools of arrestin-1 in the outer segment with different roles in photoresponse recovery. PLoS One 2011; 6:e22797. [PMID: 21818392 PMCID: PMC3144249 DOI: 10.1371/journal.pone.0022797] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 07/02/2011] [Indexed: 01/10/2023] Open
Abstract
Light-induced rhodopsin signaling is turned off with sub-second kinetics by rhodopsin phosphorylation followed by arrestin-1 binding. To test the availability of the arrestin-1 pool in dark-adapted outer segment (OS) for rhodopsin shutoff, we measured photoresponse recovery rates of mice with arrestin-1 content in the OS of 2.5%, 5%, 60%, and 100% of wild type (WT) level by two-flash ERG with the first (desensitizing) flash at 160, 400, 1000, and 2500 photons/rod. The time of half recovery (thalf) in WT retinas increases with the intensity of the initial flash, becoming ∼2.5-fold longer upon activation of 2500 than after 160 rhodopsins/rod. Mice with 60% and even 5% of WT arrestin-1 level recovered at WT rates. In contrast, the mice with 2.5% of WT arrestin-1 had a dramatically slower recovery than the other three lines, with the thalf increasing ∼28 fold between 160 and 2500 rhodopsins/rod. Even after the dimmest flash, the rate of recovery of rods with 2.5% of normal arrestin-1 was two times slower than in other lines, indicating that arrestin-1 level in the OS between 100% and 5% of WT is sufficient for rapid recovery, whereas with lower arrestin-1 the rate of recovery dramatically decreases with increased light intensity. Thus, the OS has two distinct pools of arrestin-1: cytoplasmic and a separate pool comprising ∼2.5% that is not immediately available for rhodopsin quenching. The observed delay suggests that this pool is localized at the periphery, so that its diffusion across the OS rate-limits the recovery. The line with very low arrestin-1 expression is the first where rhodopsin inactivation was made rate-limiting by arrestin manipulation.
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Affiliation(s)
- Whitney M. Cleghorn
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Elviche L. Tsakem
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Xiufeng Song
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Sergey A. Vishnivetskiy
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jungwon Seo
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jeannie Chen
- Department of Cell and Neurobiology, University of Southern California, Los Angeles, California, United States of America
| | - Eugenia V. Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Vsevolod V. Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
- * E-mail:
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Ahmed MR, Zhan X, Song X, Kook S, Gurevich VV, Gurevich EV. Ubiquitin ligase parkin promotes Mdm2-arrestin interaction but inhibits arrestin ubiquitination. Biochemistry 2011; 50:3749-63. [PMID: 21466165 DOI: 10.1021/bi200175q] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Numerous mutations in E3 ubiquitin ligase parkin were shown to associate with familial Parkinson's disease. Here we show that parkin binds arrestins, versatile regulators of cell signaling. Arrestin-parkin interaction was demonstrated by coimmunoprecipitation of endogenous proteins from brain tissue and shown to be direct using purified proteins. Parkin binding enhances arrestin interactions with another E3 ubiquitin ligase, Mdm2, apparently by shifting arrestin conformational equilibrium to the basal state preferred by Mdm2. Although Mdm2 was reported to ubiquitinate arrestins, parkin-dependent increase in Mdm2 binding dramatically reduces the ubiquitination of both nonvisual arrestins, basal and stimulated by receptor activation, without affecting receptor internalization. Several disease-associated parkin mutations differentially affect the stimulation of Mdm2 binding. All parkin mutants tested effectively suppress arrestin ubiquitination, suggesting that bound parkin shields arrestin lysines targeted by Mdm2. Parkin binding to arrestins along with its effects on arrestin interaction with Mdm2 and ubiquitination is a novel function of this protein with implications for Parkinson's disease pathology.
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Affiliation(s)
- M Rafiuddin Ahmed
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, USA
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Vishnivetskiy SA, Gimenez LE, Francis DJ, Hanson SM, Hubbell WL, Klug CS, Gurevich VV. Few residues within an extensive binding interface drive receptor interaction and determine the specificity of arrestin proteins. J Biol Chem 2011; 286:24288-99. [PMID: 21471193 DOI: 10.1074/jbc.m110.213835] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Arrestins bind active phosphorylated forms of G protein-coupled receptors, terminating G protein activation, orchestrating receptor trafficking, and redirecting signaling to alternative pathways. Visual arrestin-1 preferentially binds rhodopsin, whereas the two non-visual arrestins interact with hundreds of G protein-coupled receptor subtypes. Here we show that an extensive surface on the concave side of both arrestin-2 domains is involved in receptor binding. We also identified a small number of residues on the receptor binding surface of the N- and C-domains that largely determine the receptor specificity of arrestins. We show that alanine substitution of these residues blocks the binding of arrestin-1 to rhodopsin in vitro and of arrestin-2 and -3 to β2-adrenergic, M2 muscarinic cholinergic, and D2 dopamine receptors in intact cells, suggesting that these elements critically contribute to the energy of the interaction. Thus, in contrast to arrestin-1, where direct phosphate binding is crucial, the interaction of non-visual arrestins with their cognate receptors depends to a lesser extent on phosphate binding and more on the binding to non-phosphorylated receptor elements.
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