1
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Evenepoel P, Jørgensen HS. Skeletal parathyroid hormone hyporesponsiveness: a neglected, but clinically relevant reality in chronic kidney disease. Curr Opin Nephrol Hypertens 2024; 33:383-390. [PMID: 38651491 DOI: 10.1097/mnh.0000000000000992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
PURPOSE OF REVIEW Defining the optimal parathyroid hormone (PTH) target in chronic kidney disease (CKD) is challenging, especially for bone outcomes, due to the substantial variability in the skeleton's response to PTH. Although PTH hyporesponsiveness is as integral a component of CKD-mineral bone disorder as elevated PTH levels, clinical awareness of this condition is limited. In this review, we will discuss factors and mechanisms contributing to PTH hyporesponsiveness in CKD. This knowledge may provide clues towards a personalized approach to treating secondary hyperparathyroidism in CKD. RECENT FINDINGS Indicates a link between disturbed phosphate metabolism and impaired skeletal calcium sensing receptor signaling as an important mediator of PTH hyporesponsiveness in CKD. Further, cohort studies with diverse populations point towards differences in mineral metabolism control, rather than genetic or environmental factors, as drivers of the variability of PTH responsiveness. IN SUMMARY Skeletal PTH hyporesponsiveness in CKD has a multifactorial origin, shows important interindividual variability, and is challenging to estimate in clinical practice. The variability in skeletal responsiveness compromises PTH as a biomarker of bone turnover, especially when considering populations that are heterogeneous in ethnicity, demography, kidney function, primary kidney disease and mineral metabolism control, and in patients treated with bone targeting drugs.
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Affiliation(s)
- Pieter Evenepoel
- Department of Immunology and Transplantation, Nephrology and Renal Transplantation Research Group, KU Leuven, Belgium
- Department of Medicine, Division of Nephrology, Leuven University Hospitals, Leuven, Belgium
| | - Hanne Skou Jørgensen
- Institute of Clinical Medicine, Aarhus University, Aarhus
- Department of Nephrology, Aalborg University Hospital, Aalborg, Denmark
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2
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Shen J, Lin X, Dai F, Chen G, Lin H, Fang B, Liu H. Ubiquitin-specific peptidases: Players in bone metabolism. Cell Prolif 2023:e13444. [PMID: 36883930 PMCID: PMC10392067 DOI: 10.1111/cpr.13444] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/22/2023] [Accepted: 02/28/2023] [Indexed: 03/09/2023] Open
Abstract
Osteoporosis is an ageing-related disease, that has become a major public health problem and its pathogenesis has not yet been fully elucidated. Substantial evidence suggests a strong link between overall age-related disease progression and epigenetic modifications throughout the life cycle. As an important epigenetic modification, ubiquitination is extensively involved in various physiological processes, and its role in bone metabolism has attracted increasing attention. Ubiquitination can be reversed by deubiquitinases, which counteract protein ubiquitination degradation. As the largest and most structurally diverse cysteinase family of deubiquitinating enzymes, ubiquitin-specific proteases (USPs), comprising the largest and most structurally diverse cysteine kinase family of deubiquitinating enzymes, have been found to be important players in maintaining the balance between bone formation and resorption. The aim of this review is to explore recent findings highlighting the regulatory functions of USPs in bone metabolism and provide insight into the molecular mechanisms governing their actions during bone loss. An in-deep understanding of USPs-mediated regulation of bone formation and bone resorption will provide a scientific rationale for the discovery and development of novel USP-targeted therapeutic strategies for osteoporosis.
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Affiliation(s)
- Jianlin Shen
- Department of Orthopaedics, Affiliated Hospital of Putian University, Putian, China
| | - Xiaoning Lin
- Department of Orthopaedics, Affiliated Hospital of Putian University, Putian, China
| | - Feifei Dai
- School of Medicine, Putian Universtiy, Putian, China
| | - Guoli Chen
- Department of Orthopaedics, Affiliated Hospital of Putian University, Putian, China
| | - Haibin Lin
- Department of Orthopaedics, Affiliated Hospital of Putian University, Putian, China
| | - Bangjiang Fang
- Department of Emergency, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Institute of Emergency and Critical Care Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Huan Liu
- Department of Orthopaedics, Affiliated Hospital of Putian University, Putian, China
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3
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Ulmer CZ, Kritmetapak K, Singh RJ, Vesper HW, Kumar R. High-Resolution Mass Spectrometry for the Measurement of PTH and PTH Fragments: Insights into PTH Physiology and Bioactivity. J Am Soc Nephrol 2022; 33:1448-1458. [PMID: 35396262 PMCID: PMC9342634 DOI: 10.1681/asn.2022010036] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Full-length parathyroid hormone (PTH 1-84) is crucial for the regulation of calcium and phosphate homeostasis and bone remodeling. PTH 1-84 is metabolized into various PTH fragments, which are measured with varying levels of efficiency by PTH immunoassays. These PTH fragments, which increase in serum as CKD progresses, could potentially modulate the effects of PTH 1-84 and contribute to CKD-associated bone disorders. To obtain a true biologic representation of total PTH bioactivity, it is necessary to measure not only PTH 1-84 but also PTH fragments that are present in circulation. Traditional second-generation PTH immunoassays collectively measure PTH 1-84, PTH fragments, and post-translationally modified PTH 1-84, making it difficult to accurately predict the character of underlying renal osteodystrophy. This review highlights current advances in methods available for PTH measurement and the clinical relevance of PTH fragments in CKD. We emphasize the usefulness of mass spectrometry as a potential reference method for PTH measurement.
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Affiliation(s)
- Candice Z. Ulmer
- Clinical Chemistry Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Kittrawee Kritmetapak
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Ravinder J. Singh
- Immunochemical Core Laboratory, Mayo Clinic, Rochester, Minnesota,Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Hubert W. Vesper
- Clinical Chemistry Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Rajiv Kumar
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota,Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
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4
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Zhang Y, Du D, Fang C, Yu X, Fang Y, Liu X, Ou D, Yin H, Liu H, Wang T, Lu L, Li X, Zhang K. Epigenetics disruptions enabled by porphyrin-derived metal-organic frameworks disarm resistances to sonocatalytic ROS anti-tumor actions. FUNDAMENTAL RESEARCH 2022. [DOI: 10.1016/j.fmre.2022.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
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5
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Kitamura H, Hashimoto M. USP2-Related Cellular Signaling and Consequent Pathophysiological Outcomes. Int J Mol Sci 2021; 22:1209. [PMID: 33530560 PMCID: PMC7865608 DOI: 10.3390/ijms22031209] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 12/13/2022] Open
Abstract
Ubiquitin specific protease (USP) 2 is a multifunctional deubiquitinating enzyme. USP2 modulates cell cycle progression, and therefore carcinogenesis, via the deubiquitination of cyclins and Aurora-A. Other tumorigenic molecules, including epidermal growth factor and fatty acid synthase, are also targets for USP2. USP2 additionally prevents p53 signaling. On the other hand, USP2 functions as a key component of the CLOCK/BMAL1 complex and participates in rhythmic gene expression in the suprachiasmatic nucleus and liver. USP2 variants influence energy metabolism by controlling hepatic gluconeogenesis, hepatic cholesterol uptake, adipose tissue inflammation, and subsequent systemic insulin sensitivity. USP2 also has the potential to promote surface expression of ion channels in renal and intestinal epithelial cells. In addition to modifying the production of cytokines in immune cells, USP2 also modulates the signaling molecules that are involved in cytokine signaling in the target cells. Usp2 knockout mice exhibit changes in locomotion and male fertility, which suggest roles for USP2 in the central nervous system and male genital tract, respectively. In this review, we summarize the cellular events with USP2 contributions and list the signaling molecules that are upstream or downstream of USP2. Additionally, we describe phenotypic differences found in the in vitro and in vivo experimental models.
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Affiliation(s)
- Hiroshi Kitamura
- Laboratory of Veterinary Physiology, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan;
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6
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The deubiquitylase USP2 maintains ErbB2 abundance via counteracting endocytic degradation and represents a therapeutic target in ErbB2-positive breast cancer. Cell Death Differ 2020; 27:2710-2725. [PMID: 32327714 PMCID: PMC7429833 DOI: 10.1038/s41418-020-0538-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 03/28/2020] [Accepted: 04/01/2020] [Indexed: 12/23/2022] Open
Abstract
ErbB2 overexpression identifies a subclass of breast cancer as ErbB2-positive that is frequently associated with poor prognosis. Current ErbB2-targeted therapies have profoundly improved patient outcomes, but mutations occurring in ErbB2 have been shown to confer drug resistance. Induction of ErbB2 degradation was proposed as an intriguing strategy to battle with ErbB2-positive breast cancer and reduced mutation-incurred drug resistance. Although multiple HSP90 inhibitors have been demonstrated to effectively trigger ErbB2 degradation, none succeeded in the clinical evaluations. To develop novel ErbB2-targeting strategies, we investigated the endocytic degradation and reversible ubiquitylation of ErbB2 in breast cancer. In this study, we reveal that HSP90 inhibition leads to efficient ubiquitylation and endocytic degradation of ErbB2 through the canonical endo-lysosomal route. USP2 associates with internalized ErbB2 and prevents its lysosomal sorting and degradation via exerting deubiquitylase activity. Accordingly, the USP2 inhibitor ML364 is capable of inducing ErbB2 ubiquitylation and accelerating its turnover. ML364 potentiates the pro-degradation effects of HSP90 inhibitors on ErbB2 and hence sensitizes ErbB2-positive breast cancer cells to HSP90 inhibition. The combination of USP2 and HSP90 inhibitors effectively restrains ErbB2-positive breast cancer xenograft growth in vivo. Based on these observations, we conclude that USP2 safeguards ErbB2 surface levels by antagonizing its ubiquitylation-mediated endocytic degradation, which can be exploited to design novel therapeutic strategies against ErbB2-driven malignancies as combinatorial treatment with HSP90 inhibitors.
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7
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Deubiquitinating Enzymes and Bone Remodeling. Stem Cells Int 2018; 2018:3712083. [PMID: 30123285 PMCID: PMC6079350 DOI: 10.1155/2018/3712083] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/29/2018] [Indexed: 02/05/2023] Open
Abstract
Bone remodeling, which is essential for bone homeostasis, is controlled by multiple factors and mechanisms. In the past few years, studies have emphasized the role of the ubiquitin-dependent proteolysis system in regulating bone remodeling. Deubiquitinases, which are grouped into five families, remove ubiquitin from target proteins and are involved in several cell functions. Importantly, a number of deubiquitinases mediate bone remodeling through regulating differentiation and/or function of osteoblast and osteoclasts. In this review, we review the functions and mechanisms of deubiquitinases in mediating bone remodeling.
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8
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Liu WC, Wu CC, Lim PS, Chien SW, Hou YC, Zheng CM, Shyu JF, Lin YF, Lu KC. Effect of uremic toxin-indoxyl sulfate on the skeletal system. Clin Chim Acta 2018; 484:197-206. [PMID: 29864403 DOI: 10.1016/j.cca.2018.05.057] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/26/2018] [Accepted: 05/29/2018] [Indexed: 12/19/2022]
Abstract
Chronic kidney disease-mineral bone disorders (CKD-MBD) exhibit abnormalities in the circulating mineral levels, vitamin D metabolism, and parathyroid function that contribute to the formation of a bone lesion. The uremic toxin, indoxyl sulfate (IS), accumulates in the blood in cases of renal failure and leads to bone loss. The bone and renal responses to the action of the parathyroid hormone (PTH) are progressively decreased in CKD in spite of increasing PTH levels, a condition commonly called PTH resistance. There is a high prevalence of low bone turnover or adynamic bone disease in the early stages of CKD. This could be due to the inhibition of bone turnover, such as in PTH resistance, reduced active vitamin D levels, diabetes, aluminum, and, increased IS. With an increase in IS, there is a decrease in the osteoblast Wnt/b-catenin signaling and increase in the expression of Wnt signaling inhibitors, such as sclerostin and Dickkopf-1 (DKK1). Thus, a majority of early CKD patients exhibit deterioration of bone quality owing to the action of IS, this scenario could be termed uremic osteoporosis. However, this mechanism is complicated and not fully understood. With progressive deterioration in the renal function, IS accumulates along with persistent PTH secretion, potentially leading to high-turnover bone disease because high serum PTH levels have the ability of overriding peripheral PTH resistance and other inhibitory factors of bone formation. Finally, it leads to deterioration in bone quantity with prominent bone resorption in end stage renal disease. Uremic toxins adsorbents may decelerate oxidative stress and improve bone health in CKD patients. This review article focuses on IS and bone loss in CKD patients.
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Affiliation(s)
- Wen-Chih Liu
- Division of Nephrology, Department of Internal Medicine, Tungs' Taichung Metro Harbor Hospital, Taichung City, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chia-Chao Wu
- Division of Nephrology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Paik-Seong Lim
- Division of Nephrology, Department of Internal Medicine, Tungs' Taichung Metro Harbor Hospital, Taichung City, Taiwan
| | - Shiaw-Wen Chien
- Division of Nephrology, Department of Internal Medicine, Tungs' Taichung Metro Harbor Hospital, Taichung City, Taiwan
| | - Yi-Chou Hou
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Nephrology, Department of Medicine, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Cai-Mei Zheng
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, New Taipei City, Taiwan
| | - Jia-Fwu Shyu
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Yuh-Feng Lin
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, New Taipei City, Taiwan
| | - Kuo-Cheng Lu
- Division of Nephrology, Department of Medicine, Fu-Jen Catholic University Hospital & Cardinal-Tien Hospital, School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan.
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9
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Zhang Q, Xiao K, Liu H, Song L, McGarvey JC, Sneddon WB, Bisello A, Friedman PA. Site-specific polyubiquitination differentially regulates parathyroid hormone receptor-initiated MAPK signaling and cell proliferation. J Biol Chem 2018; 293:5556-5571. [PMID: 29444827 DOI: 10.1074/jbc.ra118.001737] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 02/06/2018] [Indexed: 01/04/2023] Open
Abstract
G protein-coupled receptor (GPCR) signaling and trafficking are essential for cellular function and regulated by phosphorylation, β-arrestin, and ubiquitination. The GPCR parathyroid hormone receptor (PTHR) exhibits time-dependent reversible ubiquitination. The exact ubiquitination sites in PTHR are unknown, but they extend upstream of its intracellular tail. Here, using tandem MS, we identified Lys388 in the third loop and Lys484 in the C-terminal tail as primary ubiquitination sites in PTHR. We found that PTHR ubiquitination requires β-arrestin and does not display a preference for β-arrestin1 or -2. PTH stimulated PTHR phosphorylation at Thr387/Thr392 and within the Ser489-Ser493 region. Such phosphorylation events may recruit β-arrestin, and we observed that chemically or genetically blocking PTHR phosphorylation inhibits its ubiquitination. Specifically, Ala replacement at Thr387/Thr392 suppressed β-arrestin binding and inhibited PTHR ubiquitination, suggesting that PTHR phosphorylation and ubiquitination are interdependent. Of note, Lys-deficient PTHR mutants promoted normal cAMP formation, but exhibited differential mitogen-activated protein kinase (MAPK) signaling. Lys-deficient PTHR triggered early onset and delayed ERK1/2 signaling compared with wildtype PTHR. Moreover, ubiquitination of Lys388 and Lys484 in wildtype PTHR strongly decreased p38 signaling, whereas Lys-deficient PTHR retained signaling comparable to unstimulated wildtype PTHR. Lys-deficient, ubiquitination-refractory PTHR reduced cell proliferation and increased apoptosis. However, elimination of all 11 Lys residues in PTHR did not affect its internalization and recycling. These results pinpoint the ubiquitinated Lys residues in PTHR controlling MAPK signaling and cell proliferation and survival. Our findings suggest new opportunities for targeting PTHR ubiquitination to regulate MAPK signaling or manage PTHR-related disorders.
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Affiliation(s)
- Qiangmin Zhang
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Kunhong Xiao
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Hongda Liu
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Lei Song
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Jennifer C McGarvey
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - W Bruce Sneddon
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Alessandro Bisello
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Peter A Friedman
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and .,the Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
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10
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Yang Y, Lei H, Qiang YW, Wang B. Ixazomib enhances parathyroid hormone-induced β-catenin/T-cell factor signaling by dissociating β-catenin from the parathyroid hormone receptor. Mol Biol Cell 2017; 28:1792-1803. [PMID: 28495797 PMCID: PMC5491187 DOI: 10.1091/mbc.e17-02-0096] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/02/2017] [Accepted: 05/03/2017] [Indexed: 12/15/2022] Open
Abstract
The proteasome inhibitor ixazomib (Izb) dissociates β-catenin from the PTH receptor to enhance PTH stimulation of β-catenin/TCF signaling through the cAMP/PKA signaling pathway. These findings provide a rationale for the use of Izb as an adjunct in the treatment of osteoporosis with PTH. The anabolic action of PTH in bone is mostly mediated by cAMP/PKA and Wnt-independent activation of β-catenin/T-cell factor (TCF) signaling. β-Catenin switches the PTH receptor (PTHR) signaling from cAMP/PKA to PLC/PKC activation by binding to the PTHR. Ixazomib (Izb) was recently approved as the first orally administered proteasome inhibitor for the treatment of multiple myeloma; it acts in part by inhibition of pathological bone destruction. Proteasome inhibitors were reported to stabilize β-catenin by the ubiquitin-proteasome pathway. However, how Izb affects PTHR activation to regulate β-catenin/TCF signaling is poorly understood. In the present study, using CRISPR/Cas9 genome-editing technology, we show that Izb reverses β-catenin–mediated PTHR signaling switch and enhances PTH-induced cAMP generation and cAMP response element–luciferase activity in osteoblasts. Izb increases active forms of β-catenin and promotes β-catenin translocation, thereby dissociating β-catenin from the PTHR at the plasma membrane. Furthermore, Izb facilitates PTH-stimulated GSK3β phosphorylation and β-catenin phosphorylation. Thus Izb enhances PTH stimulation of β-catenin/TCF signaling via cAMP-dependent activation, and this effect is due to its separating β-catenin from the PTHR. These findings provide evidence that Izb may be used to improve the therapeutic efficacy of PTH for the treatment of osteoporosis and other resorptive bone diseases.
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Affiliation(s)
- Yanmei Yang
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107
| | - Hong Lei
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107.,College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Ya-Wei Qiang
- Myeloma Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Bin Wang
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107
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Regulation of G Protein-Coupled Receptors by Ubiquitination. Int J Mol Sci 2017; 18:ijms18050923. [PMID: 28448471 PMCID: PMC5454836 DOI: 10.3390/ijms18050923] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/20/2017] [Accepted: 04/23/2017] [Indexed: 02/07/2023] Open
Abstract
G protein-coupled receptors (GPCRs) comprise the largest family of membrane receptors that control many cellular processes and consequently often serve as drug targets. These receptors undergo a strict regulation by mechanisms such as internalization and desensitization, which are strongly influenced by posttranslational modifications. Ubiquitination is a posttranslational modification with a broad range of functions that is currently gaining increased appreciation as a regulator of GPCR activity. The role of ubiquitination in directing GPCRs for lysosomal degradation has already been well-established. Furthermore, this modification can also play a role in targeting membrane and endoplasmic reticulum-associated receptors to the proteasome. Most recently, ubiquitination was also shown to be involved in GPCR signaling. In this review, we present current knowledge on the molecular basis of GPCR regulation by ubiquitination, and highlight the importance of E3 ubiquitin ligases, deubiquitinating enzymes and β-arrestins. Finally, we discuss classical and newly-discovered functions of ubiquitination in controlling GPCR activity.
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12
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13
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Pavlos NJ, Friedman PA. GPCR Signaling and Trafficking: The Long and Short of It. Trends Endocrinol Metab 2017; 28:213-226. [PMID: 27889227 PMCID: PMC5326587 DOI: 10.1016/j.tem.2016.10.007] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 10/17/2016] [Accepted: 10/26/2016] [Indexed: 01/24/2023]
Abstract
Emerging findings disclose unexpected components of G protein-coupled receptor (GPCR) signaling and cell biology. Select GPCRs exhibit classical signaling, that is restricted to cell membranes, as well as newly described persistent signaling that depends on internalization of the GPCR bound to β-arrestins. Termination of non-canonical endosomal signaling requires intraluminal acidification and sophisticated protein trafficking machineries. Recent studies reveal the structural determinants of the trafficking chaperones. This review summarizes advances in GPCR signaling and trafficking with a focus on the parathyroid hormone receptor (PTHR) as a prototype, and on the actin-sorting nexin 27 (SNX27)-retromer tubule (ASRT) complex, an endosomal sorting hub responsible for recycling and preservation of cell surface receptors. The findings are integrated into a model of PTHR trafficking with implications for signal transduction, bone growth, and mineral ion metabolism.
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Affiliation(s)
- Nathan J Pavlos
- Cellular Orthopaedic Laboratory, School of Surgery, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Peter A Friedman
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, Department of Structural Biology University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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14
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Evenepoel P, Bover J, Ureña Torres P. Parathyroid hormone metabolism and signaling in health and chronic kidney disease. Kidney Int 2016; 90:1184-1190. [PMID: 27653840 DOI: 10.1016/j.kint.2016.06.041] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 11/25/2022]
Abstract
Circulating parathyroid hormone (PTH) shows a complex relationship with hard outcomes in subjects with chronic kidney disease (CKD). Moreover, intervention studies directly targeting PTH failed to yield unequivocal results. Disturbed PTH metabolism, posttranslational modifications of PTH, and end-organ hyporesponsiveness to PTH may explain the poor performance of PTH as an outcome biomarker and precise target of therapy in the setting of CKD, at least in the gray middle target zone. PTH fragments accumulate in CKD patients and may exert effects that are distinct from, if not opposite to biointact (1-84)PTH. Posttranslational modification of PTH and especially oxidation may alter the interaction of PTH with its receptor. Its clinical relevance, however, remains a matter of ongoing debate. Less controversial is the issue of end-organ hyporesponsiveness to PTH. This phenomenon, formally referred to as PTH resistance, has long been recognized in CKD, but factors and mechanisms contributing to it remain poorly defined. Subsequent evidence identified downregulation of the PTH receptor and competing downstream signals as underlying pathophysiologic mechanisms. End-organ hyporesponsiveness to PTH in CKD, along with important analytical and biological variability, renders defining the PTH target range in CKD challenging. Although this may still be accomplished at the population level, it may prove to be very difficult at the individual level. This is a disillusioning thought in an era of personalized medicine. Parallel to the search of a functional and readily available assay quantifying PTH signaling tone or sensitivity, additional biomarkers (or a panel of biomarkers) should be formally evaluated.
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Affiliation(s)
- Pieter Evenepoel
- KU Leuven, Department of Immunology and Microbiology, Laboratory of Nephrology and University Hospitals Leuven, Department of Nephrology and Renal Transplantation, B-3000 Leuven, Belgium; Board member of the ERA-EDTA CKD-MBD Working Group.
| | - Jordi Bover
- Fundació Puigvert, Department of Nephrology, IIB Sant Pau, RedinREn, Barcelona, Catalonia, Spain; Board member of the ERA-EDTA CKD-MBD Working Group
| | - Pablo Ureña Torres
- Ramsay-Générale de Santé, Clinique du Landy, Service de Néphrologie-Dialyse, Saint Ouen, France, INSERM U1151-CNRS UMR8253 Université Paris Descartes, and Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, Paris, France; Board member of the ERA-EDTA CKD-MBD Working Group
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15
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McGarvey JC, Xiao K, Bowman SL, Mamonova T, Zhang Q, Bisello A, Sneddon WB, Ardura JA, Jean-Alphonse F, Vilardaga JP, Puthenveedu MA, Friedman PA. Actin-Sorting Nexin 27 (SNX27)-Retromer Complex Mediates Rapid Parathyroid Hormone Receptor Recycling. J Biol Chem 2016; 291:10986-1002. [PMID: 27008860 DOI: 10.1074/jbc.m115.697045] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Indexed: 01/14/2023] Open
Abstract
The G protein-coupled parathyroid hormone receptor (PTHR) regulates mineral-ion homeostasis and bone remodeling. Upon parathyroid hormone (PTH) stimulation, the PTHR internalizes into early endosomes and subsequently traffics to the retromer complex, a sorting platform on early endosomes that promotes recycling of surface receptors. The C terminus of the PTHR contains a type I PDZ ligand that binds PDZ domain-containing proteins. Mass spectrometry identified sorting nexin 27 (SNX27) in isolated endosomes as a PTHR binding partner. PTH treatment enriched endosomal PTHR. SNX27 contains a PDZ domain and serves as a cargo selector for the retromer complex. VPS26, VPS29, and VPS35 retromer subunits were isolated with PTHR in endosomes from cells stimulated with PTH. Molecular dynamics and protein binding studies establish that PTHR and SNX27 interactions depend on the PDZ recognition motif in PTHR and the PDZ domain of SNX27. Depletion of either SNX27 or VPS35 or actin depolymerization decreased the rate of PTHR recycling following agonist stimulation. Mutating the PDZ ligand of PTHR abolished the interaction with SNX27 but did not affect the overall rate of recycling, suggesting that PTHR may directly engage the retromer complex. Coimmunoprecipitation and overlay experiments show that both intact and mutated PTHR bind retromer through the VPS26 protomer and sequentially assemble a ternary complex with PTHR and SNX27. SNX27-independent recycling may involve N-ethylmaleimide-sensitive factor, which binds both PDZ intact and mutant PTHRs. We conclude that PTHR recycles rapidly through at least two pathways, one involving the ASRT complex of actin, SNX27, and retromer and another possibly involving N-ethylmaleimide-sensitive factor.
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Affiliation(s)
- Jennifer C McGarvey
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Kunhong Xiao
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Shanna L Bowman
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
| | - Tatyana Mamonova
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Qiangmin Zhang
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Alessandro Bisello
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - W Bruce Sneddon
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Juan A Ardura
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Frederic Jean-Alphonse
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Jean-Pierre Vilardaga
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and
| | - Manojkumar A Puthenveedu
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
| | - Peter A Friedman
- From the Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, and the Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
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16
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Shirakawa J, Harada H, Noda M, Ezura Y. PTH-Induced Osteoblast Proliferation Requires Upregulation of the Ubiquitin-Specific Peptidase 2 (Usp2) Expression. Calcif Tissue Int 2016; 98:306-15. [PMID: 26643174 DOI: 10.1007/s00223-015-0083-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/06/2015] [Indexed: 12/11/2022]
Abstract
Osteoporosis is a common disease that increases individual's fragility fracture risk. PTH is the only therapeutic agent for severe osteoporosis that requires anabolic action of bone formation. Although a part of the PTH actions is explained by increased proliferation of osteoblastic precursor cells, the mechanisms involved in the proliferation of osteoblastic cells by PTH have not been clarified yet. Therefore, in this study, we investigated the effects of PTH on gene expression in the cultured osteoblastic MC3T3-E1 cells, and found that the ubiquitin-specific peptidase 2 (Usp2) may be one of the direct target genes of PTHR signaling. Usp2 is a deubiquitination enzyme targeting various factors including CyclinD1 in cancer cells and PTH receptor 1 in osteoblasts. We confirmed that consistent induction of Usp2 expression peaked at 1 h by PTH1-34 (teriparatide) in MC3T3-E1 cells and primary calvarial osteoblasts. Among the three known splicing variants of the Usp2, we found the isoforms 1 and 2 are predominantly expressed in osteoblasts. Live-imaging analysis of the Fucci-transgenic mouse-derived primary osteoblasts indeed demonstrated that Usp2 is required for the PTH1-34-induced osteoblast proliferation. Western blotting analysis of the CyclinD1 indicated that Usp2 knock-down influences the paradoxical changes of CyclinD1 protein levels in this condition. Our data indicate that Usp2 is required for the PTH1-34-induced proliferation of osteoblasts.
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Affiliation(s)
- Jumpei Shirakawa
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan
- Global COE Program, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hiroyuki Harada
- Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masaki Noda
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan.
- Global COE Program, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Yoichi Ezura
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan.
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17
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Jean-Charles PY, Rajiv V, Shenoy SK. Ubiquitin-Related Roles of β-Arrestins in Endocytic Trafficking and Signal Transduction. J Cell Physiol 2016; 231:2071-80. [PMID: 26790995 DOI: 10.1002/jcp.25317] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 01/20/2016] [Indexed: 12/25/2022]
Abstract
The non-visual arrestins, β-arrestin1, and β-arrestin2 were originally identified as proteins that bind to seven-transmembrane receptors (7TMRs, also called G protein-coupled receptors, GPCRs) and block heterotrimeric G protein activation, thus leading to desensitization of transmembrane signaling. However, as subsequent discoveries have continually demonstrated, their functionality is not constrained to desensitization. They are now recognized for their critical roles in mediating intracellular trafficking of 7TMRs, growth factor receptors, ion transporters, ion channels, nuclear receptors, and non-receptor proteins. Additionally, they function as crucial mediators of ubiquitination of 7TMRs as well as other receptors and non-receptor proteins. Recently, emerging studies suggest that a class of proteins with predicted structural features of β-arrestins regulate substrate ubiquitination in yeast and higher mammals, lending support to the idea that the adaptor role of β-arrestins in protein ubiquitination is evolutionarily conserved. β-arrestins also function as scaffolds for kinases and transduce signals from 7TMRs through pathways that do not require G protein activation. Remarkably, the endocytic and scaffolding functions of β-arrestin are intertwined with its ubiquitination status; the dynamic and site specific ubiquitination on β-arrestin plays a critical role in stabilizing β-arrestin-7TMR association and the formation of signalosomes. This review summarizes the current findings on ubiquitin-dependent regulation of 7TMRs as well as β-arrestins and the potential role of reversible ubiquitination as a "biological switch" in signal transduction. J. Cell. Physiol. 231: 2071-2080, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Vishwaesh Rajiv
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina
| | - Sudha K Shenoy
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina.,Department of Cell Biology, Duke University Medical Center, Durham, North Carolina
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18
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Jean-Charles PY, Snyder JC, Shenoy SK. Chapter One - Ubiquitination and Deubiquitination of G Protein-Coupled Receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:1-55. [PMID: 27378754 DOI: 10.1016/bs.pmbts.2016.05.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The seven-transmembrane containing G protein-coupled receptors (GPCRs) constitute the largest family of cell-surface receptors. Transmembrane signaling by GPCRs is fundamental to many aspects of physiology including vision, olfaction, cardiovascular, and reproductive functions as well as pain, behavior and psychomotor responses. The duration and magnitude of signal transduction is tightly controlled by a series of coordinated trafficking events that regulate the cell-surface expression of GPCRs at the plasma membrane. Moreover, the intracellular trafficking profiles of GPCRs can correlate with the signaling efficacy and efficiency triggered by the extracellular stimuli that activate GPCRs. Of the various molecular mechanisms that impart selectivity, sensitivity and strength of transmembrane signaling, ubiquitination of the receptor protein plays an important role because it defines both trafficking and signaling properties of the activated GPCR. Ubiquitination of proteins was originally discovered in the context of lysosome-independent degradation of cytosolic proteins by the 26S proteasome; however a large body of work suggests that ubiquitination also orchestrates the downregulation of membrane proteins in the lysosomes. In the case of GPCRs, such ubiquitin-mediated lysosomal degradation engenders long-term desensitization of transmembrane signaling. To date about 40 GPCRs are known to be ubiquitinated. For many GPCRs, ubiquitination plays a major role in postendocytic trafficking and sorting to the lysosomes. This chapter will focus on the patterns and functional roles of GPCR ubiquitination, and will describe various molecular mechanisms involved in GPCR ubiquitination.
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Affiliation(s)
- P-Y Jean-Charles
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, NC, United States
| | - J C Snyder
- Department of Cell Biology, Duke University Medical Center, Durham, NC, United States
| | - S K Shenoy
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, NC, United States; Department of Cell Biology, Duke University Medical Center, Durham, NC, United States.
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19
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D. Murray R, D. Lederer E, J. Khundmiri S. Role of PTH in the Renal Handling of Phosphate. AIMS MEDICAL SCIENCE 2015. [DOI: 10.3934/medsci.2015.3.162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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20
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Roy SJ, Glazkova I, Fréchette L, Iorio-Morin C, Binda C, Pétrin D, Trieu P, Robitaille M, Angers S, Hébert TE, Parent JL. Novel, gel-free proteomics approach identifies RNF5 and JAMP as modulators of GPCR stability. Mol Endocrinol 2013; 27:1245-66. [PMID: 23798571 DOI: 10.1210/me.2013-1091] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The maturation and folding of G protein-coupled receptors are governed by mechanisms that remain poorly understood. In an effort to characterize these biological events, we optimized a novel, gel-free proteomic approach to identify partners of the β2-adrenergic receptor (β2AR). In addition to a number of known interacting proteins such as heterotrimeric G protein subunits, this allowed us to identify proteins involved in endoplasmic reticulum (ER) QC of the receptor. Among β2AR-associated proteins is Ring finger protein 5 (RNF5), an E3 ubiquitin ligase anchored to the outer membrane of the ER. Coimmunoprecipitation assays confirmed, in a cellular context, the interaction between RNF5 and the β2AR as well as the prostaglandin D2 receptor (DP). Confocal microscopy revealed that DP colocalized with RNF5 at the ER. Coexpression of RNF5 with either receptor increased levels of their expression, whereas small interfering RNA-mediated knockdown of endogenous RNF5 promoted the opposite. RNF5 did not modulate the ubiquitination state of β2AR or DP. Instead, RNF5 ubiquitinated JNK-associated membrane protein (JAMP), a protein that recruits the proteasome to the ER membrane and that is negatively regulated by RNF5-mediated ubiquitination. JAMP coimmunoprecipitated with both β2AR and DP and decreased total receptor protein levels through proteasomal degradation. Expression of DP, a receptor largely retained in the ER, promoted proteasome recruitment by JAMP. Degradation of both receptors via JAMP was increased when RNF5 was depleted. Our data suggest that RNF5 regulates the turnover of specific G protein-coupled receptors by ubiquitinating JAMP and preventing proteasome recruitment.
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Affiliation(s)
- Sébastien J Roy
- Service de Rhumatologie Département de Médecine, Université de Sherbrooke, the Institut de Pharmacologie de Sherbrooke, and the Centre de Recherche Clinique Etienne-Lebel, Sherbrooke, Québec J1H 5N4, Canada
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21
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Alonso V, Friedman PA. Minireview: ubiquitination-regulated G protein-coupled receptor signaling and trafficking. Mol Endocrinol 2013; 27:558-72. [PMID: 23471539 DOI: 10.1210/me.2012-1404] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are the largest and most diverse superfamily of membrane proteins and mediate most cellular responses to hormones and neurotransmitters. Posttranslational modifications are considered the main regulators of all GPCRs. In addition to phosphorylation, glycosylation, and palmitoylation, increasing evidence as reviewed here reveals that ubiquitination also regulates the magnitude and temporospatial aspects of GPCR signaling. Posttranslational protein modification by ubiquitin is a key molecular mechanism governing proteins degradation. Ubiquitination mediates the covalent conjugation of ubiquitin, a highly conserved polypeptide of 76 amino acids, to protein substrates. This process is catalyzed by 3 enzymes acting in tandem: an E1, ubiquitin-activating enzyme; an E2, ubiquitin-carrying enzyme; and an E3, ubiquitin ligase. Ubiquitination is counteracted by deubiquitinating enzymes that deconjugate ubiquitin-modified proteins and rescue the substrate from proteasomal degradation. Although ubiquitination is known to target many GPCRs for lysosomal or proteasomal degradation, emerging findings define novel roles for the basal status of ubiquitination and for rapid deubiquitination and transubiquitination controlling cell surface expression and cellular responsiveness of some GPCRs. In this review, we highlight the classical and novel roles of ubiquitin in the regulation of GPCR function, signaling, and trafficking.
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Affiliation(s)
- Verónica Alonso
- Institute of Applied Molecular Medicine, San Pablo-CEU University School of Medicine, Madrid, 28668, Spain
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22
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Dores MR, Trejo J. Ubiquitination of G protein-coupled receptors: functional implications and drug discovery. Mol Pharmacol 2012; 82:563-70. [PMID: 22700696 DOI: 10.1124/mol.112.079418] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
G protein-coupled receptors (GPCRs) comprise the largest and most diverse family of signaling receptors and control a vast array of physiological responses. Modulating the signaling responses of GPCRs therapeutically is important for the treatment of various diseases, and discovering new aspects of GPCR signal regulation is critical for future drug development. Post-translational modifications are integral to the regulation of GPCR function. In addition to phosphorylation, many GPCRs are reversibly modified with ubiquitin. Ubiquitin is covalently attached to lysine residues within the cytoplasmic domains of GPCRs by ubiquitin ligases and removed by ubiquitin-specific proteases. In many cases, ubiquitin functions as a sorting signal that facilitates trafficking of mammalian GPCRs from endosomes to lysosomes for degradation, but not all GPCRs use this pathway. Moreover, there are distinct types of ubiquitin conjugations that are known to serve diverse functions in controlling a wide range of cellular processes, suggesting broad roles for GPCR ubiquitination. In this review, we highlight recent studies that illustrate various roles for ubiquitin in regulation of GPCR function. Ubiquitination is known to target many GPCRs for lysosomal degradation, and current studies now indicate that basal ubiquitination, deubiquitination, and transubiquitination of certain GPCRs are important for controlling cell surface expression and cellular responsiveness. In addition, novel functions for ubiquitin in regulation of GPCR dimers and in mediating differential GPCR regulation induced by biased agonists have been reported. We will discuss the implications of these new discoveries for ubiquitin regulation of GPCR function in the context of drug development.
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Affiliation(s)
- Michael R Dores
- Department of Pharmacology, University of California, San Diego, 9500 Gilman Dr., Biomedical Sciences Building, Room 3044A, La Jolla, CA 92093, USA
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