1
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Kim K, Ashim J, Ham D, Yu W, Chung KY. Roles of the gate loop in β-arrestin-1 conformational dynamics and phosphorylated receptor interaction. Structure 2024:S0969-2126(24)00191-6. [PMID: 38889722 DOI: 10.1016/j.str.2024.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/11/2024] [Accepted: 05/22/2024] [Indexed: 06/20/2024]
Abstract
Arrestins interact with phosphorylated G protein-coupled receptors (GPCRs) and regulate the homologous desensitization and internalization of GPCRs. The gate loop in arrestins is a critical region for both stabilization of the basal state and interaction with phosphorylated receptors. We investigated the roles of specific residues in the gate loop (K292, K294, and H295) using β-arrestin-1 and phosphorylated C-tail peptide of vasopressin receptor type 2 (V2Rpp) as a model system. We measured the binding affinity of V2Rpp and analyzed conformational dynamics of β-arrestin-1. Our results suggest that K294 plays a critical role in the interaction with V2Rpp without influencing the overall conformation of the V2Rpp-bound state. The residues K292 and H295 contribute to the stability of the polar core in the basal state and form a specific conformation of the finger loop in the V2Rpp-bound state.
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Affiliation(s)
- Kiae Kim
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Janbolat Ashim
- Department of Brain Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Donghee Ham
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Wookyung Yu
- Department of Brain Sciences, DGIST, Daegu 42988, Republic of Korea.
| | - Ka Young Chung
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea.
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2
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Zheng C, Weinstein LD, Nguyen KK, Grewal A, Gurevich EV, Gurevich VV. GPCR Binding and JNK3 Activation by Arrestin-3 Have Different Structural Requirements. Cells 2023; 12:1563. [PMID: 37371033 DOI: 10.3390/cells12121563] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023] Open
Abstract
Arrestins bind active phosphorylated G protein-coupled receptors (GPCRs). Among the four mammalian subtypes, only arrestin-3 facilitates the activation of JNK3 in cells. In available structures, Lys-295 in the lariat loop of arrestin-3 and its homologue Lys-294 in arrestin-2 directly interact with the activator-attached phosphates. We compared the roles of arrestin-3 conformational equilibrium and Lys-295 in GPCR binding and JNK3 activation. Several mutants with enhanced ability to bind GPCRs showed much lower activity towards JNK3, whereas a mutant that does not bind GPCRs was more active. The subcellular distribution of mutants did not correlate with GPCR recruitment or JNK3 activation. Charge neutralization and reversal mutations of Lys-295 differentially affected receptor binding on different backgrounds but had virtually no effect on JNK3 activation. Thus, GPCR binding and arrestin-3-assisted JNK3 activation have distinct structural requirements, suggesting that facilitation of JNK3 activation is the function of arrestin-3 that is not bound to a GPCR.
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Affiliation(s)
- Chen Zheng
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Liana D Weinstein
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Kevin K Nguyen
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Abhijeet Grewal
- 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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3
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Zheng C, Weinstein LD, Nguyen KK, Grewal A, Gurevich EV, Gurevich VV. GPCR binding and JNK3 activation by arrestin-3 have different structural requirements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.01.538990. [PMID: 37205393 PMCID: PMC10187157 DOI: 10.1101/2023.05.01.538990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Arrestins bind active phosphorylated G protein-coupled receptors (GPCRs). Among the four mammalian subtypes, only arrestin-3 facilitates the activation of JNK3 in cells. In available structures, Lys-295 in the lariat loop of arrestin-3 and its homologue Lys-294 in arrestin-2 directly interact with the activator-attached phosphates. We compared the role of arrestin-3 conformational equilibrium and of Lys-295 in GPCR binding and JNK3 activation. Several mutants with enhanced ability to bind GPCRs showed much lower activity towards JNK3, whereas a mutant that does not bind GPCRs was more active. Subcellular distribution of mutants did not correlate with GPCR recruitment or JNK3 activation. Charge neutralization and reversal mutations of Lys-295 differentially affected receptor binding on different backgrounds, but had virtually no effect on JNK3 activation. Thus, GPCR binding and arrestin-3-assisted JNK3 activation have distinct structural requirements, suggesting that facilitation of JNK3 activation is the function of arrestin-3 that is not bound to a GPCR.
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4
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Jiang H, Galtes D, Wang J, Rockman HA. G protein-coupled receptor signaling: transducers and effectors. Am J Physiol Cell Physiol 2022; 323:C731-C748. [PMID: 35816644 PMCID: PMC9448338 DOI: 10.1152/ajpcell.00210.2022] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/27/2022] [Accepted: 07/10/2022] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCRs) are of considerable interest due to their importance in a wide range of physiological functions and in a large number of Food and Drug Administration (FDA)-approved drugs as therapeutic entities. With continued study of their function and mechanism of action, there is a greater understanding of how effector molecules interact with a receptor to initiate downstream effector signaling. This review aims to explore the signaling pathways, dynamic structures, and physiological relevance in the cardiovascular system of the three most important GPCR signaling effectors: heterotrimeric G proteins, GPCR kinases (GRKs), and β-arrestins. We will first summarize their prominent roles in GPCR pharmacology before transitioning into less well-explored areas. As new technologies are developed and applied to studying GPCR structure and their downstream effectors, there is increasing appreciation for the elegance of the regulatory mechanisms that mediate intracellular signaling and function.
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Affiliation(s)
- Haoran Jiang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Daniella Galtes
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Jialu Wang
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina
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5
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Scaffolding mechanism of arrestin-2 in the cRaf/MEK1/ERK signaling cascade. Proc Natl Acad Sci U S A 2021; 118:2026491118. [PMID: 34507982 DOI: 10.1073/pnas.2026491118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2021] [Indexed: 01/14/2023] Open
Abstract
Arrestins were initially identified for their role in homologous desensitization and internalization of G protein-coupled receptors. Receptor-bound arrestins also initiate signaling by interacting with other signaling proteins. Arrestins scaffold MAPK signaling cascades, MAPK kinase kinase (MAP3K), MAPK kinase (MAP2K), and MAPK. In particular, arrestins facilitate ERK1/2 activation by scaffolding ERK1/2 (MAPK), MEK1 (MAP2K), and Raf (MAPK3). However, the structural mechanism underlying this scaffolding remains unknown. Here, we investigated the mechanism of arrestin-2 scaffolding of cRaf, MEK1, and ERK2 using hydrogen/deuterium exchange-mass spectrometry, tryptophan-induced bimane fluorescence quenching, and NMR. We found that basal and active arrestin-2 interacted with cRaf, while only active arrestin-2 interacted with MEK1 and ERK2. The ATP binding status of MEK1 or ERK2 affected arrestin-2 binding; ATP-bound MEK1 interacted with arrestin-2, whereas only empty ERK2 bound arrestin-2. Analysis of the binding interfaces suggested that the relative positions of cRaf, MEK1, and ERK2 on arrestin-2 likely facilitate sequential phosphorylation in the signal transduction cascade.
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6
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Receptor-Arrestin Interactions: The GPCR Perspective. Biomolecules 2021; 11:biom11020218. [PMID: 33557162 PMCID: PMC7913897 DOI: 10.3390/biom11020218] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/25/2021] [Accepted: 02/01/2021] [Indexed: 02/06/2023] Open
Abstract
Arrestins are a small family of four proteins in most vertebrates that bind hundreds of different G protein-coupled receptors (GPCRs). Arrestin binding to a GPCR has at least three functions: precluding further receptor coupling to G proteins, facilitating receptor internalization, and initiating distinct arrestin-mediated signaling. The molecular mechanism of arrestin–GPCR interactions has been extensively studied and discussed from the “arrestin perspective”, focusing on the roles of arrestin elements in receptor binding. Here, we discuss this phenomenon from the “receptor perspective”, focusing on the receptor elements involved in arrestin binding and emphasizing existing gaps in our knowledge that need to be filled. It is vitally important to understand the role of receptor elements in arrestin activation and how the interaction of each of these elements with arrestin contributes to the latter’s transition to the high-affinity binding state. A more precise knowledge of the molecular mechanisms of arrestin activation is needed to enable the construction of arrestin mutants with desired functional characteristics.
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7
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Şensoy Ö. The single nucleotide β -arrestin2 variant, A248T, resembles dynamical properties of activated arrestin. Turk J Chem 2021; 44:409-420. [PMID: 33488166 PMCID: PMC7671214 DOI: 10.3906/kim-1910-46] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/28/2020] [Indexed: 12/30/2022] Open
Abstract
β -arrestins are responsible for termination of G protein-coupled receptor (GPCR)-mediated signaling. Association of single nucleotide variants with onset of crucial diseases has made this protein family hot targets in the field of GPCR-mediated pharmacology. However, impact of these mutations on function of these variants has remained elusive. In this study, structural and dynamical properties of one of β -arrestin2 (arrestin 3) variants, A248T, which has been identified in some cancer tissue samples, were investigated via molecular dynamics simulations. The results showed that the variant underwent structural rearrangements which are seen in crystal structures of active arrestin. Specifically, the "short helix" unravels and the "gate loop" swings forward as seen in crystal structures of receptor-bound and GPCR phosphopeptide-bound arrestin. Moreover, the "finger loop" samples upward position in the variant. Importantly, these regions harbor crucial residues that are involved in receptor binding interfaces. Cumulatively, these local structural rearrangements help the variant adopt active-like domain angle without perturbing the "polar core". Considering that phosphorylation of the receptor is required for activation of arrestin, A248T might serve as a model system to understand phosphorylation-independent activation mechanism, thus enabling modulation of function of arrestin variants which are activated independent of receptor phosphorylation as seen in cancer.
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Affiliation(s)
- Özge Şensoy
- Department of Computer Engineering, The School of Engineering and Natural Sciences, İstanbul Medipol University, İstanbul Turkey
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8
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Dissecting the structural features of β-arrestins as multifunctional proteins. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140603. [PMID: 33421644 DOI: 10.1016/j.bbapap.2021.140603] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/21/2020] [Accepted: 01/04/2021] [Indexed: 02/08/2023]
Abstract
β-arrestins bind active G protein-coupled receptors (GPCRs) and play a crucial role in receptor desensitization and internalization. The classical paradigm of arrestin function has been expanded with the identification of many non-receptor-binding partners, which indicated the multifunctional role of β-arrestins in cellular functions. To elucidate the molecular mechanism of β-arrestin-mediated signaling, the structural features of β-arrestins were investigated using X-ray crystallography and cryogenic electron microscopy (cryo-EM). However, the intrinsic conformational flexibility of β-arrestins hampers the elucidation of structural interactions between β-arrestins and their binding partners using conventional structure determination tools. Therefore, structural information obtained using complementary structure analysis techniques would be necessary in combination with X-ray crystallography and cryo-EM data. In this review, we describe how β-arrestins interact with their binding partners from a structural point of view, as elucidated by both traditional methods (X-ray crystallography and cryo-EM) and complementary structure analysis techniques.
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9
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Many faces of the GPCR-arrestin interaction. Arch Pharm Res 2020; 43:890-899. [DOI: 10.1007/s12272-020-01263-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 08/11/2020] [Indexed: 01/14/2023]
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10
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Phosphorylated peptide of G protein-coupled receptor induces dimerization in activated arrestin. Sci Rep 2020; 10:10938. [PMID: 32616825 PMCID: PMC7331637 DOI: 10.1038/s41598-020-67944-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 06/16/2020] [Indexed: 11/08/2022] Open
Abstract
Termination of the G-protein-coupled receptor signaling involves phosphorylation of its C-terminus and subsequent binding of the regulatory protein arrestin. In the visual system, arrestin-1 preferentially binds to photoactivated and phosphorylated rhodopsin and inactivates phototransduction. Here, we have investigated binding of a synthetic phosphopeptide of bovine rhodopsin (residues 323-348) to the active variants of visual arrestin-1: splice variant p44, and the mutant R175E. Unlike the wild type arrestin-1, both these arrestins are monomeric in solution. Solution structure analysis using small angle X-ray scattering supported by size exclusion chromatography results reveal dimerization in both the arrestins in the presence of phosphopeptide. Our results are the first report, to our knowledge, on receptor-induced oligomerization in arrestin, suggesting possible roles for the cellular function of arrestin oligomers. Given high structural homology and the similarities in their activation mechanism, these results are expected to have implications for all arrestin isoforms.
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11
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Min K, Yoon HJ, Park JY, Baidya M, Dwivedi-Agnihotri H, Maharana J, Chaturvedi M, Chung KY, Shukla AK, Lee HH. Crystal Structure of β-Arrestin 2 in Complex with CXCR7 Phosphopeptide. Structure 2020; 28:1014-1023.e4. [PMID: 32579945 DOI: 10.1016/j.str.2020.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 04/02/2020] [Accepted: 06/03/2020] [Indexed: 12/21/2022]
Abstract
β-Arrestins (βarrs) critically regulate G-protein-coupled receptor (GPCR) signaling and trafficking. βarrs have two isoforms, βarr1 and βarr2. Receptor phosphorylation is a key determinant for the binding of βarrs, and understanding the intricate details of receptor-βarr interaction is the next frontier in GPCR structural biology. The high-resolution structure of active βarr1 in complex with a phosphopeptide derived from GPCR has been revealed, but that of βarr2 remains elusive. Here, we present a 2.3-Å crystal structure of βarr2 in complex with a phosphopeptide (C7pp) derived from the carboxyl terminus of CXCR7. The structural analysis of C7pp-bound βarr2 reveals key differences from the previously determined active conformation of βarr1. One of the key differences is that C7pp-bound βarr2 shows a relatively small inter-domain rotation. Antibody-fragment-based conformational sensor and hydrogen/deuterium exchange experiments further corroborated the structural features of βarr2 and suggested that βarr2 adopts a range of inter-domain rotations.
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Affiliation(s)
- Kyungjin Min
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Hye-Jin Yoon
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Young Park
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Mithu Baidya
- Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | | | - Jagannath Maharana
- Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Madhu Chaturvedi
- Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Ka Young Chung
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea.
| | - Arun K Shukla
- Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India.
| | - Hyung Ho Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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12
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Conformational Dynamics and Functional Implications of Phosphorylated β-Arrestins. Structure 2020; 28:314-323.e3. [DOI: 10.1016/j.str.2019.12.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 11/25/2019] [Accepted: 12/21/2019] [Indexed: 12/18/2022]
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13
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Chen Q, Iverson TM, Gurevich VV. Structural Basis of Arrestin-Dependent Signal Transduction. Trends Biochem Sci 2018; 43:412-423. [PMID: 29636212 PMCID: PMC5959776 DOI: 10.1016/j.tibs.2018.03.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/03/2018] [Accepted: 03/12/2018] [Indexed: 12/29/2022]
Abstract
Arrestins are a small family of proteins with four isoforms in humans. Remarkably, two arrestins regulate signaling from >800 G protein-coupled receptors (GPCRs) or nonreceptor activators by simultaneously binding an activator and one out of hundreds of other signaling proteins. When arrestins are bound to GPCRs or other activators, the affinity for these signaling partners changes. Thus, it is proposed that an activator alters arrestin's ability to transduce a signal. The comparison of all available arrestin structures identifies several common conformational rearrangements associated with activation. In particular, it identifies elements that are directly involved in binding to GPCRs or other activators, elements that likely engage distinct downstream effectors, and elements that likely link the activator-binding sites with the effector-binding sites.
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Affiliation(s)
- Qiuyan Chen
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47906, USA
| | - Tina M Iverson
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-0146, USA; Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-0146, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN 37232-0146, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232-0146, USA.
| | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-0146, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232-0146, USA.
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14
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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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15
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Hilger D, Masureel M, Kobilka BK. Structure and dynamics of GPCR signaling complexes. Nat Struct Mol Biol 2018; 25:4-12. [PMID: 29323277 PMCID: PMC6535338 DOI: 10.1038/s41594-017-0011-7] [Citation(s) in RCA: 539] [Impact Index Per Article: 89.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/21/2017] [Indexed: 12/16/2022]
Abstract
G-protein-coupled receptors (GPCRs) relay numerous extracellular signals by triggering intracellular signaling through coupling with G proteins and arrestins. Recent breakthroughs in the structural determination of GPCRs and GPCR-transducer complexes represent important steps toward deciphering GPCR signal transduction at a molecular level. A full understanding of the molecular basis of GPCR-mediated signaling requires elucidation of the dynamics of receptors and their transducer complexes as well as their energy landscapes and conformational transition rates. Here, we summarize current insights into the structural plasticity of GPCR-G-protein and GPCR-arrestin complexes that underlies the regulation of the receptor's intracellular signaling profile.
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Affiliation(s)
- Daniel Hilger
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Matthieu Masureel
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Brian K Kobilka
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.
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16
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Chen Q, Perry NA, Vishnivetskiy SA, Berndt S, Gilbert NC, Zhuo Y, Singh PK, Tholen J, Ohi MD, Gurevich EV, Brautigam CA, Klug CS, Gurevich VV, Iverson TM. Structural basis of arrestin-3 activation and signaling. Nat Commun 2017; 8:1427. [PMID: 29127291 PMCID: PMC5681653 DOI: 10.1038/s41467-017-01218-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 08/29/2017] [Indexed: 02/06/2023] Open
Abstract
A unique aspect of arrestin-3 is its ability to support both receptor-dependent and receptor-independent signaling. Here, we show that inositol hexakisphosphate (IP6) is a non-receptor activator of arrestin-3 and report the structure of IP6-activated arrestin-3 at 2.4-Å resolution. IP6-activated arrestin-3 exhibits an inter-domain twist and a displaced C-tail, hallmarks of active arrestin. IP6 binds to the arrestin phosphate sensor, and is stabilized by trimerization. Analysis of the trimerization surface, which is also the receptor-binding surface, suggests a feature called the finger loop as a key region of the activation sensor. We show that finger loop helicity and flexibility may underlie coupling to hundreds of diverse receptors and also promote arrestin-3 activation by IP6. Importantly, we show that effector-binding sites on arrestins have distinct conformations in the basal and activated states, acting as switch regions. These switch regions may work with the inter-domain twist to initiate and direct arrestin-mediated signaling. While arrestins are mainly associated with GPCR signaling, arrestin-3 can signal independently of receptor interaction. Here the authors present the structure of arrestin-3 bound to inositol hexakisphosphate (IP6) and propose a model for arrestin-3 activation.
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Affiliation(s)
- Qiuyan Chen
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Nicole A Perry
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | | | - Sandra Berndt
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Nathaniel C Gilbert
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA.,Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Ya Zhuo
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Prashant K Singh
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Jonas Tholen
- University of Applied Sciences Emden/Leer, Emden, 26723, Germany
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA.,Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA.,Center for Structural Biology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Chad A Brautigam
- Departments of Biophysics and Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Candice S Klug
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA.
| | - T M Iverson
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA. .,Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA. .,Center for Structural Biology, Vanderbilt University, Nashville, TN, 37232, USA. .,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, 37232, USA.
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17
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Scheerer P, Sommer ME. Structural mechanism of arrestin activation. Curr Opin Struct Biol 2017; 45:160-169. [PMID: 28600951 DOI: 10.1016/j.sbi.2017.05.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 04/24/2017] [Accepted: 05/01/2017] [Indexed: 01/14/2023]
Abstract
The large and multifunctional family of G protein-coupled receptors (GPCRs) are regulated by a small family of structurally conserved arrestin proteins. In order to bind an active GPCR, arrestin must first be activated by interaction with the phosphorylated receptor C-terminus. Recent years have witnessed major developments in high-resolution crystal structures of pre-active arrestins and arrestin or arrestin-derived peptides in complex with an active GPCR. Although each structure individually offers only a limited snapshot, taken together and interpreted in light of recent complementary functional data, they offer valuable insight into how arrestin is activated by and couples to a phosphorylated active GPCR.
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Affiliation(s)
- Patrick Scheerer
- Institute of Medical Physics and Biophysics (CC2), Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Group Protein X-ray Crystallography & Signal Transduction, Germany.
| | - Martha E Sommer
- Institute of Medical Physics and Biophysics (CC2), Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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18
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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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19
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Lally CCM, Bauer B, Selent J, Sommer ME. C-edge loops of arrestin function as a membrane anchor. Nat Commun 2017; 8:14258. [PMID: 28220785 PMCID: PMC5321764 DOI: 10.1038/ncomms14258] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 12/13/2016] [Indexed: 01/14/2023] Open
Abstract
G-protein-coupled receptors are membrane proteins that are regulated by a small family of arrestin proteins. During formation of the arrestin-receptor complex, arrestin first interacts with the phosphorylated receptor C terminus in a pre-complex, which activates arrestin for tight receptor binding. Currently, little is known about the structure of the pre-complex and its transition to a high-affinity complex. Here we present molecular dynamics simulations and site-directed fluorescence experiments on arrestin-1 interactions with rhodopsin, showing that loops within the C-edge of arrestin function as a membrane anchor. Activation of arrestin by receptor-attached phosphates is necessary for C-edge engagement of the membrane, and we show that these interactions are distinct in the pre-complex and high-affinity complex in regard to their conformation and orientation. Our results expand current knowledge of C-edge structure and further illuminate the conformational transitions that occur in arrestin along the pathway to tight receptor binding.
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Affiliation(s)
- Ciara C M. Lally
- Institute of Medical Physics and Biophysics (CC2), Charité Medical University, Charitéplatz 1, Berlin 10117, Germany
| | - Brian Bauer
- Institute of Medical Physics and Biophysics (CC2), Charité Medical University, Charitéplatz 1, Berlin 10117, Germany
| | - Jana Selent
- Research Programme on Biomedical Informatics, Department of Experimental and Health Sciences, Pompeu Fabra University, Hospital del Mar Medical Research Institute, Carrer del Dr. Aiguader, 88, Barcelona 08003, Spain
| | - Martha E Sommer
- Institute of Medical Physics and Biophysics (CC2), Charité Medical University, Charitéplatz 1, Berlin 10117, Germany
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20
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Schlesinger R, Cousin A, Granzin J, Batra-Safferling R. Expression and purification of arrestin in yeast Saccharomyces cerevisiae. Methods Cell Biol 2017; 142:159-172. [DOI: 10.1016/bs.mcb.2017.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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21
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Sensoy O, Moreira IS, Morra G. Understanding the Differential Selectivity of Arrestins toward the Phosphorylation State of the Receptor. ACS Chem Neurosci 2016; 7:1212-24. [PMID: 27405242 DOI: 10.1021/acschemneuro.6b00073] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Proteins in the arrestin family exhibit a conserved structural fold that nevertheless allows for significant differences in their selectivity for G-protein coupled receptors (GPCRs) and their phosphorylation states. To reveal the mechanism of activation that prepares arrestin for selective interaction with GPCRs, and to understand the basis for these differences, we used unbiased molecular dynamics simulations to compare the structural and dynamic properties of wild type Arr1 (Arr1-WT), Arr3 (Arr3-WT), and a constitutively active Arr1 mutant, Arr1-R175E, characterized by a perturbation of the phosphate recognition region called "polar core". We find that in our simulations the mutant evolves toward a conformation that resembles the known preactivated structures of an Arr1 splice-variant, and the structurally similar phosphopeptide-bound Arr2-WT, while this does not happen for Arr1-WT. Hence, we propose an activation allosteric mechanism connecting the perturbation of the polar core to a global conformational change, including the relative reorientation of N- and C-domains, and the emergence of electrostatic properties of putative binding surfaces. The underlying local structural changes are interpreted as markers of the evolution of an arrestin structure toward an active-like conformation. Similar activation related changes occur in Arr3-WT in the absence of any perturbation of the polar core, suggesting that this system could spontaneously visit preactivated states in solution. This hypothesis is proposed to explain the lower selectivity of Arr3 toward nonphosphorylated receptors. Moreover, by elucidating the allosteric mechanism underlying activation, we identify functionally critical regions on arrestin structure that can be targeted with drugs or chemical tools for functional modulation.
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Affiliation(s)
- Ozge Sensoy
- The School of Engineering and Natural Sciences, Istanbul Medipol University, 34810 Istanbul, Turkey
- Department of Physiology and Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, New York 10065, United States
| | - Irina S. Moreira
- CNC - Center for Neuroscience and Cell Biology; Rua Larga, FMUC, Polo I, 1°andar, Universidade de Coimbra, 3004-517 Coimbra, Portugal
- Bijvoet Center for Biomolecular Research,
Faculty of Science - Chemistry, Utrecht University, Utrecht 3584CH, The Netherlands
| | - Giulia Morra
- Department of Physiology and Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, New York 10065, United States
- ICRM-CNR
Istituto di Chimica del Riconoscimento Molecolare, Consiglio Nazionale delle Ricerche, Via Mario Bianco 9, 20131 Milano, Italia
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22
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Peterhans C, Lally CCM, Ostermaier MK, Sommer ME, Standfuss J. Functional map of arrestin binding to phosphorylated opsin, with and without agonist. Sci Rep 2016; 6:28686. [PMID: 27350090 PMCID: PMC4923902 DOI: 10.1038/srep28686] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 06/01/2016] [Indexed: 01/06/2023] Open
Abstract
Arrestins desensitize G protein-coupled receptors (GPCRs) and act as mediators of signalling. Here we investigated the interactions of arrestin-1 with two functionally distinct forms of the dim-light photoreceptor rhodopsin. Using unbiased scanning mutagenesis we probed the individual contribution of each arrestin residue to the interaction with the phosphorylated apo-receptor (Ops-P) and the agonist-bound form (Meta II-P). Disruption of the polar core or displacement of the C-tail strengthened binding to both receptor forms. In contrast, mutations of phosphate-binding residues (phosphosensors) suggest the phosphorylated receptor C-terminus binds arrestin differently for Meta II-P and Ops-P. Likewise, mutations within the inter-domain interface, variations in the receptor-binding loops and the C-edge of arrestin reveal different binding modes. In summary, our results indicate that arrestin-1 binding to Meta II-P and Ops-P is similarly dependent on arrestin activation, although the complexes formed with these two receptor forms are structurally distinct.
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Affiliation(s)
- Christian Peterhans
- Paul Scherrer Institute, Laboratory for Biomolecular Research, CH-5323, Villigen, Switzerland
| | - Ciara C M Lally
- Institut für Medizinische Physik und Biophysik (CC2), Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117, Berlin, Germany
| | - Martin K Ostermaier
- Institut für Medizinische Physik und Biophysik (CC2), Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117, Berlin, Germany
| | - Martha E Sommer
- Institut für Medizinische Physik und Biophysik (CC2), Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117, Berlin, Germany
| | - Jörg Standfuss
- Paul Scherrer Institute, Laboratory for Biomolecular Research, CH-5323, Villigen, Switzerland
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23
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Smith JS, Rajagopal S. The β-Arrestins: Multifunctional Regulators of G Protein-coupled Receptors. J Biol Chem 2016; 291:8969-77. [PMID: 26984408 DOI: 10.1074/jbc.r115.713313] [Citation(s) in RCA: 209] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The β-arrestins (βarrs) are versatile, multifunctional adapter proteins that are best known for their ability to desensitize G protein-coupled receptors (GPCRs), but also regulate a diverse array of cellular functions. To signal in such a complex fashion, βarrs adopt multiple conformations and are regulated at multiple levels to differentially activate downstream pathways. Recent structural studies have demonstrated that βarrs have a conserved structure and activation mechanism, with plasticity of their structural fold, allowing them to adopt a wide array of conformations. Novel roles for βarrs continue to be identified, demonstrating the importance of these dynamic regulators of cellular signaling.
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Affiliation(s)
| | - Sudarshan Rajagopal
- From the Departments of Biochemistry and Medicine, Duke University Medical Center, Durham, North Carolina 27710
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