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Jin J, He Y, Guo J, Pan Q, Wei X, Xu C, Qi Z, Li Q, Ma S, Lin J, Jiang N, Ma J, Wang X, Jiang L, Ding Q, Osto E, Zhi X, Meng D. BACH1 controls hepatic insulin signaling and glucose homeostasis in mice. Nat Commun 2023; 14:8428. [PMID: 38129407 PMCID: PMC10739811 DOI: 10.1038/s41467-023-44088-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Hepatic insulin resistance is central to the metabolic syndrome. Here we investigate the role of BTB and CNC homology 1 (BACH1) in hepatic insulin signaling. BACH1 is elevated in the hepatocytes of individuals with obesity and patients with non-alcoholic fatty liver disease (NAFLD). Hepatocyte-specific Bach1 deletion in male mice on a high-fat diet (HFD) ameliorates hyperglycemia and insulin resistance, improves glucose homeostasis, and protects against steatosis, whereas hepatic overexpression of Bach1 in male mice leads to the opposite phenotype. BACH1 directly interacts with the protein-tyrosine phosphatase 1B (PTP1B) and the insulin receptor β (IR-β), and loss of BACH1 reduces the interaction between PTP1B and IR-β upon insulin stimulation and enhances insulin signaling in hepatocytes. Inhibition of PTP1B significantly attenuates BACH1-mediated suppression of insulin signaling in HFD-fed male mice. Hepatic BACH1 knockdown ameliorates hyperglycemia and improves insulin sensitivity in diabetic male mice. These results demonstrate a critical function for hepatic BACH1 in the regulation of insulin signaling and glucose homeostasis.
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Affiliation(s)
- Jiayu Jin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Yunquan He
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Jieyu Guo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Qi Pan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Xiangxiang Wei
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Chen Xu
- Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Zhiyuan Qi
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Qinhan Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Siyu Ma
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Jiayi Lin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Nan Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Jinghua Ma
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Xinhong Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Lindi Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Qiurong Ding
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Elena Osto
- Division of Physiology and Pathophysiology, Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Medical University of Graz, Graz, Austria
| | - Xiuling Zhi
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
| | - Dan Meng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
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Liang Y, Bai J, Xie Z, Lian Z, Guo J, Zhao F, Liang Y, Huo H, Gong H. Tomato sucrose transporter SlSUT4 participates in flowering regulation by modulating gibberellin biosynthesis. PLANT PHYSIOLOGY 2023; 192:1080-1098. [PMID: 36943245 PMCID: PMC10231472 DOI: 10.1093/plphys/kiad162] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 02/14/2023] [Accepted: 02/26/2023] [Indexed: 06/01/2023]
Abstract
The functions of sucrose transporters (SUTs) differ among family members. The physiological function of SUT1 has been studied intensively, while that of SUT4 in various plant species including tomato (Solanum lycopersicum) is less well-understood. In this study, we characterized the function of tomato SlSUT4 in the regulation of flowering using a combination of molecular and physiological analyses. SlSUT4 displayed transport activity for sucrose when expressed in yeast (Saccharomyces cerevisiae), and it localized at both the plasma membrane and tonoplast. SlSUT4 interacted with SlSUT1, causing partial internalization of the latter, the main phloem loader of sucrose in tomato. Silencing of SlSUT4 promoted SlSUT1 localization to the plasma membrane, contributing to increased sucrose export and thus increased sucrose level in the shoot apex, which promoted flowering. Both silencing of SlSUT4 and spraying with sucrose suppressed gibberellin biosynthesis through repression of ent-kaurene oxidase and gibberellin 20-oxidase-1 (2 genes encoding key enzymes in gibberellin biosynthesis) expression by SlMYB76, which directly bound to their promoters. Silencing of SlMYB76 promoted gibberellin biosynthesis. Our results suggest that SlSUT4 is a functional SUT in tomato; downregulation of SlSUT4 expression enhances sucrose transport to the shoot apex, which promotes flowering by inhibiting gibberellin biosynthesis.
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Affiliation(s)
- Yufei Liang
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Jiayu Bai
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Zhilong Xie
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Zhaoyuan Lian
- Mid-Florida Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 2725 South Binion Road, Apopka, FL 32703, USA
| | - Jia Guo
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Feiyang Zhao
- College of Life Sciences, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Yan Liang
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
| | - Heqiang Huo
- Mid-Florida Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 2725 South Binion Road, Apopka, FL 32703, USA
| | - Haijun Gong
- Shaanxi Engineering Research Center for Vegetables/College of Horticulture, Northwest A&F University,Yangling, Shaanxi 712100, China
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Bourebaba L, Serwotka-Suszczak A, Pielok A, Sikora M, Mularczyk M, Marycz K. The PTP1B inhibitor MSI-1436 ameliorates liver insulin sensitivity by modulating autophagy, ER stress and systemic inflammation in Equine metabolic syndrome affected horses. Front Endocrinol (Lausanne) 2023; 14:1149610. [PMID: 37020593 PMCID: PMC10067883 DOI: 10.3389/fendo.2023.1149610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 03/08/2023] [Indexed: 04/07/2023] Open
Abstract
BACKGROUND Equine metabolic syndrome (EMS) is a multifactorial pathology gathering insulin resistance, low-grade inflammation and past or chronic laminitis. Among the several molecular mechanisms underlying EMS pathogenesis, increased negative insulin signalling regulation mediated by protein tyrosine phosphatase 1 B (PTP1B) has emerged as a critical axis in the development of liver insulin resistance and general metabolic distress associated to increased ER stress, inflammation and disrupted autophagy. Thus, the use of PTP1B selective inhibitors such as MSI-1436 might be considered as a golden therapeutic tool for the proper management of EMS and associated conditions. Therefore, the present investigation aimed at verifying the clinical efficacy of MSI-1436 systemic administration on liver metabolic balance, insulin sensitivity and inflammatory status in EMS affected horses. Moreover, the impact of MSI-1436 treatment on liver autophagy machinery and associated ER stress in liver tissue has been analysed. METHODS Liver explants isolated from healthy and EMS horses have been treated with MSI-1436 prior to gene and protein expression analysis of main markers mediating ER stress, mitophagy and autophagy. Furthermore, EMS horses have been intravenously treated with a single dose of MSI-1436, and evaluated for their metabolic and inflammatory status. RESULTS Clinical application of MSI-1436 to EMS horses restored proper adiponectin levels and attenuated the typical hyperinsulinemia and hyperglycemia. Moreover, administration of MSI-1436 further reduced the circulating levels of key pro-inflammatory mediators including IL-1β, TNF-α and TGF-β and triggered the Tregs cells activation. At the molecular level, PTP1B inhibition resulted in a noticeable mitigation of liver ER stress, improvement of mitochondrial dynamics and consequently, a regulation of autophagic response. Similarly, short-term ex vivo treatment of EMS liver explants with trodusquemine (MSI-1436) substantially enhanced autophagy by upregulating the levels of HSC70 and Beclin-1 at both mRNA and protein level. Moreover, the PTP1B inhibitor potentiated mitophagy and associated expression of MFN2 and PINK1. Interestingly, inhibition of PTP1B resulted in potent attenuation of ER stress key mediators' expression namely, CHOP, ATF6, HSPA5 and XBP1. CONCLUSION Presented findings shed for the first time promising new insights in the development of an MSI-1436-based therapy for proper equine metabolic syndrome intervention and may additionally find potential translational application to human metabolic syndrome treatment.
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Affiliation(s)
- Lynda Bourebaba
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
- International Institute of Translational Medicine, Wisznia Mała, Poland
| | - Anna Serwotka-Suszczak
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Ariadna Pielok
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Mateusz Sikora
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Malwina Mularczyk
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
- International Institute of Translational Medicine, Wisznia Mała, Poland
| | - Krzysztof Marycz
- Department of Experimental Biology, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
- *Correspondence: Krzysztof Marycz,
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Shah MA, Haris M, Faheem HI, Hamid A, Yousaf R, Rasul A, Shah GM, Khalil AAK, Wahab A, Khan H, Alhasani RH, Althobaiti NA. Cross-Talk between Obesity and Diabetes: Introducing Polyphenols as an Effective Phytomedicine to Combat the Dual Sword Diabesity. Curr Pharm Des 2022; 28:1523-1542. [PMID: 35762558 DOI: 10.2174/1381612828666220628123224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/06/2022] [Indexed: 12/15/2022]
Abstract
: Obesity-associated diabetes mellitus, a chronic metabolic affliction accounting for 90% of all diabetic patients, has been affecting humanity extremely badly and escalating the risk of developing other serious disorders. It is observed that 0.4 billion people globally have diabetes, whose major cause is obesity. Currently, innumerable synthetic drugs like alogliptin and rosiglitazone are being used to get through diabetes, but they have certain complications, restrictions with severe side effects, and toxicity issues. Recently, the frequency of plant-derived phytochemicals as advantageous substitutes against diabesity is increasing progressively due to their unparalleled benefit of producing less side effects and toxicity. Of these phytochemicals, dietary polyphenols have been accepted as potent agents against the dual sword "diabesity". These polyphenols target certain genes and molecular pathways through dual mechanisms such as adiponectin upregulation, cannabinoid receptor antagonism, free fatty acid oxidation, ghrelin antagonism, glucocorticoid inhibition, sodium-glucose cotransporter inhibition, oxidative stress and inflammation inhibition etc. which sequentially help to combat both diabetes and obesity. In this review, we have summarized the most beneficial natural polyphenols along with their complex molecular pathways during diabesity.
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Affiliation(s)
| | - Muhammad Haris
- Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Hafiza Ishmal Faheem
- Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Ayesha Hamid
- Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Rimsha Yousaf
- Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Azhar Rasul
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Ghulam Mujtaba Shah
- Department of Pharmacy, Hazara University, Mansehra, Pakistan.,Department of Botany, Hazara University, Mansehra, Pakistan
| | - Atif Ali Khan Khalil
- Department of Biological Sciences, National University of Medical Sciences, Rawalpindi 46000, Pakistan
| | - Abdul Wahab
- Department of Pharmacy, Kohat University of Science & Technology, Kohat, Pakistan
| | - Haroon Khan
- Department of Pharmacy, Abdul Wali Khan University, Mardan, Pakistan
| | - Reem Hasaballah Alhasani
- Department of Biology, Faculty of Applied Science, Umm Al-Qura University, 21961 Makkah, Saudi Arabia
| | - Nora A Althobaiti
- Department of Biology, College of Science and Humanities-Al Quwaiiyah, Shaqra University, Al Quwaiiyah, Saudi Arabia
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Liao Z, Zhang C, Ding L, Moyers JS, Tang JX, Beals JM. Comprehensive insulin receptor phosphorylation dynamics profiled by mass spectrometry. FEBS J 2021; 289:2657-2671. [PMID: 34826178 DOI: 10.1111/febs.16299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 11/09/2021] [Accepted: 11/25/2021] [Indexed: 02/03/2023]
Abstract
Insulin receptor (IR) phosphorylation is critical for the assessment of the extent of IR agonism and nuances in the downstream signaling cascade. A thorough identification and monitoring of the phosphorylation events is important for understanding the process of insulin signaling transduction and regulation. Although IR phosphorylation has been studied extensively in the past decades, only a handful of phosphorylation sites can be identified by either traditional antibody-based assays or recent large-scale mass spectrometry-based phosphoproteomics approaches. In the present study, the most exhaustive assessment of the IR phosphorylation was conducted using nano-liquid chromatography-tandem mass spectrometry, in which 13 IR phosphorylation sites and 22 combinations thereof were analyzed. The kinetic analysis included Y965, Y972, S968/969, and S974/976 in the juxtamembrane region; Y1158, Y1162, and Y1163 in the kinase domain; and Y1328, Y1334, S1278, S1320, S1321, and T1348 in the C-terminal region. Employing two different receptor agonists (i.e. insulin and an IR peptide agonist), the data revealed contrasting phosphorylation kinetics across these sites with dynamics far more diverse than expected for known IR agonists. Notably, cell trafficking experiments revealed that the IR peptide agonist was incapable of inducing IR to the early endosome, which is probably linked to a difference in IR phosphorylation. The present study provides a powerful tool for investigating IR signaling and trafficking that will benefit the design of IR agonists with improved therapeutic utility.
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Affiliation(s)
- Zhongping Liao
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
| | - Chen Zhang
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
| | - Liyun Ding
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
| | - Julie S Moyers
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
| | - Jason X Tang
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
| | - John M Beals
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
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6
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Joy-Immediato M, Ramirez MJ, Cerda M, Toyama Y, Ravasio A, Kanchanawong P, Bertocchi C. Junctional ER Organization Affects Mechanotransduction at Cadherin-Mediated Adhesions. Front Cell Dev Biol 2021; 9:669086. [PMID: 34222239 PMCID: PMC8247578 DOI: 10.3389/fcell.2021.669086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/23/2021] [Indexed: 11/13/2022] Open
Abstract
Cadherin-mediated adhesions (also known as adherens junctions) are adhesive complexes that connect neighboring cells in a tissue. While the role of the actin cytoskeleton in withstanding tension at these sites of contact is well documented, little is known about the involvement of microtubules and the associated endoplasmic reticulum (ER) network in cadherin mechanotransduction. Therefore, we investigated how the organization of ER extensions in close proximity of cadherin-mediated adhesions can affect such complexes, and vice versa. Here, we show that the extension of the ER to cadherin-mediated adhesions is tension dependent and appears to be cadherin-type specific. Furthermore, the different structural organization of the ER/microtubule network seems to affect the localization of ER-bound PTP1B at cadherin-mediated adhesions. This phosphatase is involved in the modulation of vinculin, a molecular clutch which enables differential engagement of the cadherin-catenin layer with the actomyosin cytoskeleton in response to tension. This suggests a link between structural organization of the ER/microtubule network around cadherin-specific adhesions, to control the mechanotransduction of adherens junctions by modulation of vinculin conformational state.
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Affiliation(s)
- Michelle Joy-Immediato
- Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Manuel J Ramirez
- Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mauricio Cerda
- Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Center for Medical Informatics and Telemedicine, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Yusuke Toyama
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Andrea Ravasio
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pakorn Kanchanawong
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore.,Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, Singapore
| | - Cristina Bertocchi
- Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
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Shevchuk M, Wang Q, Pajkert R, Xu J, Mei H, Röschenthaler G, Han J. Recent Advances in Synthesis of Difluoromethylene Phosphonates for Biological Applications. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001464] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Michael Shevchuk
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Qian Wang
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Romana Pajkert
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Jingcheng Xu
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Haibo Mei
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Gerd‐Volker Röschenthaler
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Jianlin Han
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
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8
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A review on ameliorative green nanotechnological approaches in diabetes management. Biomed Pharmacother 2020; 127:110198. [DOI: 10.1016/j.biopha.2020.110198] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 04/19/2020] [Accepted: 04/27/2020] [Indexed: 12/16/2022] Open
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9
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Bohnert M. Tether Me, Tether Me Not—Dynamic Organelle Contact Sites in Metabolic Rewiring. Dev Cell 2020; 54:212-225. [DOI: 10.1016/j.devcel.2020.06.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/17/2020] [Accepted: 06/20/2020] [Indexed: 02/04/2023]
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10
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Lee CA, Blackstone C. ER morphology and endo-lysosomal crosstalk: Functions and disease implications. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158544. [PMID: 31678515 DOI: 10.1016/j.bbalip.2019.158544] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 02/03/2023]
Abstract
The endoplasmic reticulum (ER) is a continuous endomembrane system comprising the nuclear envelope, ribosome-studded sheets, dense peripheral matrices, and an extensive polygonal network of interconnected tubules. In addition to performing numerous critical cellular functions, the ER makes extensive contacts with other organelles, including endosomes and lysosomes. The molecular and functional characterization of these contacts has advanced significantly over the past several years. These contacts participate in key functions such as cholesterol transfer, endosome tubule fission, and Ca2+ exchange. Disruption of key proteins at these sites can result in often severe diseases, particularly those affecting the nervous system.
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Affiliation(s)
- Crystal A Lee
- Cell Biology Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Craig Blackstone
- Cell Biology Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
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11
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Durgannavar T, Kwon SJ, Ghisaidoobe ABT, Rho K, Kim JH, Yoon S, Kang HJ, Chung SJ. Label‐Free Detection of Protein Tyrosine Phosphatase 1B (PTP1B) by Using a Rationally Designed Förster Resonance Energy Transfer (FRET) Probe. Chembiochem 2018; 19:2495-2501. [DOI: 10.1002/cbic.201800529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Indexed: 01/10/2023]
Affiliation(s)
| | - Se Jeong Kwon
- School of PharmacySungkyunkwan University Suwon 16419 Republic of Korea
| | | | - Kyungmin Rho
- Department of ChemistryDongguk University Seoul 100–715 Republic of Korea
| | - Ju Hwan Kim
- Department of ChemistryDongguk University Seoul 100–715 Republic of Korea
| | - Sun‐Young Yoon
- School of PharmacySungkyunkwan University Suwon 16419 Republic of Korea
| | - Hyo Jin Kang
- Department of ChemistryDongguk University Seoul 100–715 Republic of Korea
| | - Sang J. Chung
- School of PharmacySungkyunkwan University Suwon 16419 Republic of Korea
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12
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Xu SH, Xu W, Wang L, Hu YK, Liu JP, Zhao Y, Li MJ, Li F, Huang SX, Zhao Y. New phloroglucinol derivatives with protein tyrosine phosphatase 1B (PTP1B) inhibitory activities from Syzygium austroyunnanense. Fitoterapia 2018; 131:141-145. [DOI: 10.1016/j.fitote.2018.10.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/03/2018] [Accepted: 10/07/2018] [Indexed: 10/28/2022]
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13
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Guzmán-Ávila R, Flores-Morales V, Paoli P, Camici G, Ramírez-Espinosa JJ, Cerón-Romero L, Navarrete-Vázquez G, Hidalgo-Figueroa S, Yolanda Rios M, Villalobos-Molina R, Estrada-Soto S. Ursolic acid derivatives as potential antidiabetic agents: In vitro, in vivo, and in silico studies. Drug Dev Res 2018; 79:70-80. [PMID: 29380400 DOI: 10.1002/ddr.21422] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 01/10/2023]
Abstract
Hit, Lead & Candidate Discovery Protein tyrosine phosphatase 1B (PTP-1B) has attracted interest as a novel target for the treatment of type 2 diabetes, this because its role in the insulin-signaling pathway as a negative regulator. Thus, the aim of current work was to obtain seven ursolic acid derivatives as potential antidiabetic agents with PTP-1B inhibition as main mechanism of action. Furthermore, derivatives 1-7 were submitted in vitro to enzymatic PTP-1B inhibition being 3, 5, and 7 the most active compounds (IC50 = 5.6, 4.7, and 4.6 μM, respectively). In addition, results were corroborated with in silico docking studies with PTP-1B orthosteric site A and extended binding site B, showed that 3 had polar and Van der Waals interactions in both sites with Lys120, Tyr46, Ser216, Ala217, Ile219, Asp181, Phe182, Gln262, Val49, Met258, and Gly259, showing a docking score value of -7.48 Kcal/mol, being more specific for site A. Moreover, compound 7 showed polar interaction with Gln262 and Van der Waals interactions with Ala217, Phe182, Ile219, Arg45, Tyr46, Arg47, Asp48, and Val49 with a predictive docking score of -6.43 kcal/mol, suggesting that the potential binding site could be localized in the site B adjacent to the catalytic site A. Finally, derivatives 2 and 7 (50 mg/kg) were selected to establish their in vivo antidiabetic effect using a noninsulin-dependent diabetes mice model, showing significant blood glucose lowering compared with control group (p < .05).
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Affiliation(s)
- Ricardo Guzmán-Ávila
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, Mexico
| | - Virginia Flores-Morales
- Laboratorio de Síntesis Asimétrica y Bioenergética (LSAyB), Unidad Académica de Ciencias Químicas, Universidad Autónoma de Zacatecas, Zacatecas, Zacatecas, 98160, Mexico
| | - Paolo Paoli
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Sezione di Scienze Biochimiche, Universitá degli Studi di Firenze, Firenze, 50134, Italy
| | - Guido Camici
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Sezione di Scienze Biochimiche, Universitá degli Studi di Firenze, Firenze, 50134, Italy
| | - Juan José Ramírez-Espinosa
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Juárez, Chihuahua, 32310, Mexico
| | - Litzia Cerón-Romero
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, Mexico
| | - Gabriel Navarrete-Vázquez
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, Mexico
| | - Sergio Hidalgo-Figueroa
- Cátedras CONACyT IPICYT/Consorcio de Investigación, Innovación y Desarrollo para las Zonas Áridas, San Luis Potosí, 78216, Mexico
| | - Maria Yolanda Rios
- Centro de Investigaciones Químicas, IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, Mexico
| | - Rafael Villalobos-Molina
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, 54090, México
| | - Samuel Estrada-Soto
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, Mexico
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14
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Caldieri G, Malabarba MG, Di Fiore PP, Sigismund S. EGFR Trafficking in Physiology and Cancer. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2018; 57:235-272. [PMID: 30097778 DOI: 10.1007/978-3-319-96704-2_9] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Signaling from the epidermal growth factor receptor (EGFR) elicits multiple biological responses, including cell proliferation, migration, and survival. Receptor endocytosis and trafficking are critical physiological processes that control the strength, duration, diversification, and spatial restriction of EGFR signaling through multiple mechanisms, which we review in this chapter. These mechanisms include: (i) regulation of receptor density and activation at the cell surface; (ii) concentration of receptors into distinct nascent endocytic structures; (iii) commitment of the receptor to different endocytic routes; (iv) endosomal sorting and postendocytic trafficking of the receptor through distinct pathways, and (v) recycling to restricted regions of the cell surface. We also highlight how communication between organelles controls EGFR activity along the endocytic route. Finally, we illustrate how abnormal trafficking of EGFR oncogenic mutants, as well as alterations of the endocytic machinery, contributes to aberrant EGFR signaling in cancer.
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Affiliation(s)
- Giusi Caldieri
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Maria Grazia Malabarba
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Pier Paolo Di Fiore
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Sara Sigismund
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy.
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy.
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15
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Sorokoumov VN, Shpakov AO. Protein phosphotyrosine phosphatase 1B: Structure, function, role in the development of metabolic disorders and their correction by the enzyme inhibitors. J EVOL BIOCHEM PHYS+ 2017. [DOI: 10.1134/s0022093017040020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Thiebaut PA, Besnier M, Gomez E, Richard V. Role of protein tyrosine phosphatase 1B in cardiovascular diseases. J Mol Cell Cardiol 2016; 101:50-57. [DOI: 10.1016/j.yjmcc.2016.09.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/31/2016] [Accepted: 09/01/2016] [Indexed: 12/14/2022]
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17
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Okeke E, Dingsdale H, Parker T, Voronina S, Tepikin AV. Endoplasmic reticulum-plasma membrane junctions: structure, function and dynamics. J Physiol 2016; 594:2837-47. [PMID: 26939537 DOI: 10.1113/jp271142] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/13/2016] [Indexed: 12/20/2022] Open
Abstract
Endoplasmic reticulum (ER)-plasma membrane (PM) junctions are contact sites between the ER and the PM; the distance between the two organelles in the junctions is below 40 nm and the membranes are connected by protein tethers. A number of molecular tools and technical approaches have been recently developed to visualise, modify and characterise properties of ER-PM junctions. The junctions serve as the platforms for lipid exchange between the organelles and for cell signalling, notably Ca(2+) and cAMP signalling. Vice versa, signalling events regulate the development and properties of the junctions. Two Ca(2+) -dependent mechanisms of de novo formation of ER-PM junctions have been recently described and characterised. The junction-forming proteins and lipids are currently the focus of vigorous investigation. Junctions can be relatively short-lived and simple structures, forming and dissolving on the time scale of a few minutes. However, complex, sophisticated and multifunctional ER-PM junctions, capable of attracting numerous protein residents and other cellular organelles, have been described in some cell types. The road from simplicity to complexity, i.e. the transformation from simple 'nascent' ER-PM junctions to advanced stable multiorganellar complexes, is likely to become an attractive research avenue for current and future junctologists. Another area of considerable research interest is the downstream cellular processes that can be activated by specific local signalling events in the ER-PM junctions. Studies of the cell physiology and indeed pathophysiology of ER-PM junctions have already produced some surprising discoveries, likely to expand with advances in our understanding of these remarkable organellar contact sites.
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Affiliation(s)
- Emmanuel Okeke
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK
| | - Hayley Dingsdale
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK
| | - Tony Parker
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK
| | - Svetlana Voronina
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK
| | - Alexei V Tepikin
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK
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18
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Lee D, Kraus A, Prins D, Groenendyk J, Aubry I, Liu WX, Li HD, Julien O, Touret N, Sykes BD, Tremblay ML, Michalak M. UBC9-dependent association between calnexin and protein tyrosine phosphatase 1B (PTP1B) at the endoplasmic reticulum. J Biol Chem 2015; 290:5725-38. [PMID: 25586181 DOI: 10.1074/jbc.m114.635474] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Calnexin is a type I integral endoplasmic reticulum (ER) membrane protein, molecular chaperone, and a component of the translocon. We discovered a novel interaction between the calnexin cytoplasmic domain and UBC9, a SUMOylation E2 ligase, which modified the calnexin cytoplasmic domain by the addition of SUMO. We demonstrated that calnexin interaction with the SUMOylation machinery modulates an interaction with protein tyrosine phosphatase 1B (PTP1B), an ER-associated protein tyrosine phosphatase involved in the negative regulation of insulin and leptin signaling. We showed that calnexin and PTP1B form UBC9-dependent complexes, revealing a previously unrecognized contribution of calnexin to the retention of PTP1B at the ER membrane. This work shows that the SUMOylation machinery links two ER proteins from divergent pathways to potentially affect cellular protein quality control and energy metabolism.
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Affiliation(s)
- Dukgyu Lee
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Allison Kraus
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Daniel Prins
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Jody Groenendyk
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Isabelle Aubry
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Wen-Xin Liu
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Hao-Dong Li
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Olivier Julien
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Nicolas Touret
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Brian D Sykes
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Michel L Tremblay
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Marek Michalak
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
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19
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Abstract
Low-grade inflammation is an established pathological condition that contributes to the development of obesity, insulin resistance and type 2 diabetes. Metabolic inflammation is dependent on multiple signalling events. In an overnutrition state, canonical inflammatory pathways are induced by inflammatory cytokines and lipid species. They can also be triggered through inflammasome activation as well as through cellular stress provoked by the unfolded protein response at the endoplasmic reticulum as well as by reactive oxygen species. In this chapter, we summarize the current knowledge about signalling events within the cell and describe how they impact on metabolic inflammation and whole-body metabolism. We particularly highlight the interplay between different signalling pathways that link low-grade inflammation responses to the inactivation of the insulin receptor pathway, ultimately leading to insulin resistance, a hallmark of type 2 diabetes.
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20
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Bakke J, Haj FG. Protein-tyrosine phosphatase 1B substrates and metabolic regulation. Semin Cell Dev Biol 2014; 37:58-65. [PMID: 25263014 DOI: 10.1016/j.semcdb.2014.09.020] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/15/2014] [Accepted: 09/21/2014] [Indexed: 01/19/2023]
Abstract
Metabolic homeostasis requires integration of complex signaling networks which, when deregulated, contribute to metabolic syndrome and related disorders. Protein-tyrosine phosphatase 1B (PTP1B) has emerged as a key regulator of signaling networks that are implicated in metabolic diseases such as obesity and type 2 diabetes. In this review, we examine mechanisms that regulate PTP1B-substrate interaction, enzymatic activity and experimental approaches to identify PTP1B substrates. We then highlight findings that implicate PTP1B in metabolic regulation. In particular, insulin and leptin signaling are discussed as well as recently identified PTP1B substrates that are involved in endoplasmic reticulum stress response, cell-cell communication, energy balance and vesicle trafficking. In summary, PTP1B exhibits exquisite substrate specificity and is an outstanding pharmaceutical target for obesity and type 2 diabetes.
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Affiliation(s)
- Jesse Bakke
- Department of Nutrition, University of California Davis, One Shields Ave, Davis, CA 95616, United States
| | - Fawaz G Haj
- Department of Nutrition, University of California Davis, One Shields Ave, Davis, CA 95616, United States; Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, University of California Davis, Sacramento, CA 95817, United States; Comprehensive Cancer Center, University of California Davis, Sacramento, CA 95817, United States.
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21
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Desbuquois B, Authier F. [Involvement of the endosomal compartment in cellular insulin signaling]. Biol Aujourdhui 2014; 208:137-150. [PMID: 25190573 DOI: 10.1051/jbio/2014016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Indexed: 06/03/2023]
Abstract
The insulin receptor and insulin signaling proteins downstream the receptor reside in different subcellular compartments and undergo redistribution within the cell upon insulin activation. Endocytosis of the insulin-receptor complex, by mediating ligand degradation and receptor dephosphorylation, is generally viewed as a mechanism which attenuates or arrests insulin signal transduction. However, several observations suggest that insulin receptor endocytosis and/or recruitement of insulin signaling proteins to endosomes are also involved in a positive regulation of insulin signaling: (1) upon internalization, the insulin receptor remains transiently phosphorylated and activated; (2) in insulin-stimulated cells or tissues, signaling proteins of the PI3K/Akt and Ras/Raf/Mek/Erk pathways are recruited to endosomes or other intracellular compartments, in which they undergo phosphorylation and/or activation; and (3) depletion or overexpression of proteins involved in the regulation of membrane trafficking and endocytosis interfere with insulin signaling. These observations support a spatial and temporal regulation of insulin signal transduction and reinforce the concept that, as for other membrane signaling receptors, endocytosis and signaling are functionally linked.
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Affiliation(s)
- Bernard Desbuquois
- Inserm U1016 et CNRS UMR 8104, Institut Cochin, et Université Paris Descartes, 24 rue du Faubourg Saint Jacques, 75014 Paris, France
| | - François Authier
- Service Information Scientifique et Technique (IST) de l'Inserm, Délégation Régionale Inserm Paris V, 2 rue d'Alésia, 75014 Paris, France
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22
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Zhang X, Simons M. Receptor tyrosine kinases endocytosis in endothelium: biology and signaling. Arterioscler Thromb Vasc Biol 2014; 34:1831-7. [PMID: 24925972 DOI: 10.1161/atvbaha.114.303217] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Receptor tyrosine kinases are involved in regulation of key processes in endothelial biology, including proliferation, migration, and angiogenesis. It is now generally accepted that receptor tyrosine kinase signaling occurs intracellularly and on the plasma membrane, although many important details remain to be worked out. Endocytosis and subsequent intracellular trafficking spatiotemporally regulate receptor tyrosine kinase signaling, whereas signaling endosomes provide a platform for the compartmentalization of signaling events. This review summarizes recent advances in our understanding of endothelial receptor tyrosine kinase endocytosis and signaling using vascular endothelial growth factor receptor-2 as a paradigm.
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Affiliation(s)
- Xi Zhang
- From the Department of Cell Biology, and Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Michael Simons
- From the Department of Cell Biology, and Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT.
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23
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Specialization of mitochondrial and vascular oxidant modulated VEGFR in the denervated skeletal muscle. Cell Signal 2013; 25:2106-14. [DOI: 10.1016/j.cellsig.2013.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/17/2013] [Accepted: 06/25/2013] [Indexed: 01/30/2023]
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24
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The nucleus- and endoplasmic reticulum-targeted forms of protein tyrosine phosphatase 61F regulate Drosophila growth, life span, and fecundity. Mol Cell Biol 2013; 33:1345-56. [PMID: 23339871 DOI: 10.1128/mcb.01411-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The protein tyrosine phosphatases (PTPs) T cell PTP (TCPTP) and PTP1B share a high level of catalytic domain sequence and structural similarity yet display distinct differences in substrate recognition and function. Their noncatalytic domains contribute to substrate selectivity and function by regulating TCPTP nucleocytoplasmic shuttling and targeting PTP1B to the endoplasmic reticulum (ER). The Drosophila TCPTP/PTP1B orthologue PTP61F has two variants with identical catalytic domains that are differentially targeted to the ER and nucleus. Here we demonstrate that the PTP61F variants differ in their ability to negatively regulate insulin signaling in vivo, with the nucleus-localized form (PTP61Fn) being more effective than the ER-localized form (PTP61Fm). We report that PTP61Fm is reliant on the adaptor protein Dock to attenuate insulin signaling in vivo. Also, we show that the PTP61F variants differ in their capacities to regulate growth, with PTP61Fn but not PTP61Fm attenuating cellular proliferation. Furthermore, we generate a mutant lacking both PTP61F variants, which displays a reduction in median life span and a decrease in female fecundity, and show that both variants are required to rescue these mutant phenotypes. Our findings define the role of PTP61F in life span and fecundity and reinforce the importance of subcellular localization in mediating PTP function in vivo.
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25
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Muppirala M, Gupta V, Swarup G. Emerging role of tyrosine phosphatase, TCPTP, in the organelles of the early secretory pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:1125-32. [PMID: 23328081 DOI: 10.1016/j.bbamcr.2013.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 01/04/2013] [Accepted: 01/08/2013] [Indexed: 01/21/2023]
Abstract
T-cell protein tyrosine phosphatase, TCPTP, is a ubiquitously expressed non-receptor type tyrosine phosphatase. There are two splice variants of TCPTP, TC48 and TC45, which differ in their sub-cellular localizations and functions. TC45 is a nuclear protein, which has both nuclear and cytoplasmic substrates, and is involved in many signaling events including endocytic recycling of platelet-derived growth factor β-receptor. TC48 is a predominantly endoplasmic reticulum (ER)-localizing protein, which dephosphorylates some of the substrates of TC45 at the ER. However, recently few specific substrates for TC48 have been identified. These include C3G (RapGEF1), syntaxin 17 and BCR-Abl. TC48 moves from the ER to post-ER compartments, the ER-Golgi intermediate compartment (ERGIC) and Golgi, and it is retrieved back to the ER. The retrieval of ER proteins from post-ER compartments is generally believed as a mechanism of targeting these proteins to the ER. However, it is possible that this shuttling of TC48 serves to regulate signaling in the early secretory pathway. For example, TC48 dephosphorylates phosphorylated C3G at the Golgi and inhibits neurite outgrowth. TC48 interacts with and dephosphorylates syntaxin 17, which is an ER and ERGIC-localizing protein involved in vesicle transport. A yeast two-hybrid screen identified several unique interacting partners of TC48 belonging to two groups - proteins involved in vesicle trafficking and proteins involved in cell adhesion. These interacting proteins could be substrates or regulators of TC48 function and localization. Thus, the role of TC48 seems to be more diverse, which is still to be explored.
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Affiliation(s)
- Madhavi Muppirala
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Hyderabad, India
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26
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ER-bound protein tyrosine phosphatase PTP1B interacts with Src at the plasma membrane/substrate interface. PLoS One 2012; 7:e38948. [PMID: 22701734 PMCID: PMC3372476 DOI: 10.1371/journal.pone.0038948] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 05/15/2012] [Indexed: 12/17/2022] Open
Abstract
PTP1B is an endoplasmic reticulum (ER) anchored enzyme whose access to substrates is partly dependent on the ER distribution and dynamics. One of these substrates, the protein tyrosine kinase Src, has been found in the cytosol, endosomes, and plasma membrane. Here we analyzed where PTP1B and Src physically interact in intact cells, by bimolecular fluorescence complementation (BiFC) in combination with temporal and high resolution microscopy. We also determined the structural basis of this interaction. We found that BiFC signal is displayed as puncta scattered throughout the ER network, a feature that was enhanced when the substrate trapping mutant PTP1B-D181A was used. Time-lapse and co-localization analyses revealed that BiFC puncta did not correspond to vesicular carriers; instead they localized at the tip of dynamic ER tubules. BiFC puncta were retained in ventral membrane preparations after cell unroofing and were also detected within the evanescent field of total internal reflection fluorescent microscopy (TIRFM) associated to the ventral membranes of whole cells. Furthermore, BiFC puncta often colocalized with dark spots seen by surface reflection interference contrast (SRIC). Removal of Src myristoylation and polybasic motifs abolished BiFC. In addition, PTP1B active site and negative regulatory tyrosine 529 on Src were primary determinants of BiFC occurrence, although the SH3 binding motif on PTP1B also played a role. Our results suggest that ER-bound PTP1B dynamically interacts with the negative regulatory site at the C-terminus of Src at random puncta in the plasma membrane/substrate interface, likely leading to Src activation and recruitment to adhesion complexes. We postulate that this functional ER/plasma membrane crosstalk could apply to a wide array of protein partners, opening an exciting field of research.
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27
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Haj FG, Sabet O, Kinkhabwala A, Wimmer-Kleikamp S, Roukos V, Han HM, Grabenbauer M, Bierbaum M, Antony C, Neel BG, Bastiaens PI. Regulation of signaling at regions of cell-cell contact by endoplasmic reticulum-bound protein-tyrosine phosphatase 1B. PLoS One 2012; 7:e36633. [PMID: 22655028 PMCID: PMC3360045 DOI: 10.1371/journal.pone.0036633] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 04/04/2012] [Indexed: 12/17/2022] Open
Abstract
Protein-tyrosine phosphatase 1B (PTP1B) is a ubiquitously expressed PTP that is anchored to the endoplasmic reticulum (ER). PTP1B dephosphorylates activated receptor tyrosine kinases after endocytosis, as they transit past the ER. However, PTP1B also can access some plasma membrane (PM)-bound substrates at points of cell-cell contact. To explore how PTP1B interacts with such substrates, we utilized quantitative cellular imaging approaches and mathematical modeling of protein mobility. We find that the ER network comes in close proximity to the PM at apparently specialized regions of cell-cell contact, enabling PTP1B to engage substrate(s) at these sites. Studies using PTP1B mutants show that the ER anchor plays an important role in restricting its interactions with PM substrates mainly to regions of cell-cell contact. In addition, treatment with PTP1B inhibitor leads to increased tyrosine phosphorylation of EphA2, a PTP1B substrate, specifically at regions of cell-cell contact. Collectively, our results identify PM-proximal sub-regions of the ER as important sites of cellular signaling regulation by PTP1B.
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Affiliation(s)
- Fawaz G. Haj
- Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, United States of America
- Nutrition Department, University of California Davis, Davis, California, United States of America
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
| | - Ola Sabet
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Ali Kinkhabwala
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Sabine Wimmer-Kleikamp
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Vassilis Roukos
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Hong-Mei Han
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Markus Grabenbauer
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Martin Bierbaum
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Claude Antony
- European Molecular Biology Laboratories, Heidelberg, Germany
| | - Benjamin G. Neel
- Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, United States of America
- Campbell Family Cancer Research Institute, Ontario Cancer Institute, Princess Margaret Hospital, University Health Network, and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
| | - Philippe I. Bastiaens
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
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28
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Abstract
Insulin resistance is a key pathological feature of type 2 diabetes and is characterized by defects in signaling by the insulin receptor (IR) protein tyrosine kinase. The inhibition of protein tyrosine phosphatases (PTPs) that antagonize IR signaling may provide a means for enhancing the insulin response and alleviating insulin resistance. The prototypic phosphotyrosine-specific phosphatase PTP1B dephosphorylates the IR and attenuates insulin signaling in muscle and liver. Mice that are deficient for PTP1B exhibit improved glucose homeostasis in diet and genetic models of insulin resistance and type 2 diabetes. The phosphatase TCPTP shares 72% catalytic domain sequence identity with PTP1B and has also been implicated in IR regulation. Despite their high degree of similarity, PTP1B and TCPTP act together in vitro and in vivo to regulate insulin signaling and glucose homeostasis. This review highlights their capacity to act specifically and nonredundantly in cellular signaling, describes their roles in IR regulation and glucose homeostasis, and discusses their potential as drug targets for the enhancement of IR phosphorylation and insulin sensitivity in type 2 diabetes.
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Affiliation(s)
- Tony Tiganis
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia.
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29
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Haque A, Andersen JN, Salmeen A, Barford D, Tonks NK. Conformation-sensing antibodies stabilize the oxidized form of PTP1B and inhibit its phosphatase activity. Cell 2011; 147:185-98. [PMID: 21962515 DOI: 10.1016/j.cell.2011.08.036] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 06/30/2011] [Accepted: 08/15/2011] [Indexed: 01/10/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) plays important roles in downregulation of insulin and leptin signaling and is an established therapeutic target for diabetes and obesity. PTP1B is regulated by reactive oxygen species (ROS) produced in response to various stimuli, including insulin. The reversibly oxidized form of the enzyme (PTP1B-OX) is inactive and undergoes profound conformational changes at the active site. We generated conformation-sensor antibodies, in the form of single-chain variable fragments (scFvs), that stabilize PTP1B-OX and thereby inhibit its phosphatase function. Expression of conformation-sensor scFvs as intracellular antibodies (intrabodies) enhanced insulin-induced tyrosyl phosphorylation of the β subunit of the insulin receptor and its substrate IRS-1 and increased insulin-induced phosphorylation of PKB/AKT. Our data suggest that stabilization of the oxidized, inactive form of PTP1B with appropriate therapeutic molecules may offer a paradigm for phosphatase drug development.
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Affiliation(s)
- Aftabul Haque
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
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30
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Boubekeur S, Boute N, Pagesy P, Zilberfarb V, Christeff N, Issad T. A new highly efficient substrate-trapping mutant of protein tyrosine phosphatase 1B (PTP1B) reveals full autoactivation of the insulin receptor precursor. J Biol Chem 2011; 286:19373-80. [PMID: 21487008 DOI: 10.1074/jbc.m111.222984] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
PTP1B is a protein tyrosine-phosphatase located on the cytosolic side of the endoplasmic reticulum that plays an important role in the regulation of the insulin receptor (IR). Replacement of the conserved Asp-181 by alanine is known to convert PTP1B into a substrate-trapping protein that binds to but cannot dephosphorylate its substrates. In this work, we have studied the effect of an additional mutation (Y46F) on the substrate-trapping efficiency of PTP1B-D181A. We observed that this mutation converts PTP1B-D181A into a highly efficient substrate-trapping mutant, resulting in much higher recovery of tyrosine-phosphorylated proteins coimmunoprecipitated with PTP1B. Bioluminescence resonance energy transfer (BRET) experiments were also performed to compare the dynamics of interaction of the IR with these mutants. Basal BRET, which mainly reflects the interaction of PTP1B with the IR precursor during its biosynthesis in the endoplasmic reticulum, was markedly increased with the PTP1B-D181A-Y46F mutant. In contrast, insulin-induced BRET was markedly reduced with PTP1B-D181A-Y46F. I(125) insulin binding experiments indicated that PTP1B-D181-Y46F reduced the expression of IR at the plasma membrane. Reduced expression at the cell surface was associated with higher amounts of the uncleaved IR precursor in the cell. Moreover, we observed that substantial amounts of the uncleaved IR precursor reached the Tris-phosphorylated, fully activated form in an insulin independent fashion. These results support the notion that PTP1B plays a crucial role in the control of the activity of the IR precursor during its biosynthesis. In addition, this new substrate-trapping mutant may be a valuable tool for the identification of new PTP1B substrates.
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Ramírez-Espinosa JJ, Rios MY, López-Martínez S, López-Vallejo F, Medina-Franco JL, Paoli P, Camici G, Navarrete-Vázquez G, Ortiz-Andrade R, Estrada-Soto S. Antidiabetic activity of some pentacyclic acid triterpenoids, role of PTP-1B: in vitro, in silico, and in vivo approaches. Eur J Med Chem 2011; 46:2243-51. [PMID: 21453996 DOI: 10.1016/j.ejmech.2011.03.005] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 02/28/2011] [Accepted: 03/01/2011] [Indexed: 01/06/2023]
Abstract
The aim of the current study was to investigate the oral antidiabetic activity of four structurally-related triterpenic acids: ursolic (RE-01), oleanolic (RE-02), moronic (RE-03) and morolic (RE-04) acids. STZ-nicotinamide diabetic rats were treated with these triterpenes (50 mg/kg) and the antidiabetic effects in acute experiment were determined. All compounds showed significant antidiabetic activity in comparison with control group (p<0.05). The in vitro inhibitory activity of compounds against protein tyrosine phosphatase 1B (PTP-1B) was also evaluated. At 50 μM, the enzymatic activity was almost completely inhibited. All compounds were docked with a crystal structure of PTP-1B. Docking results suggested the potential binding of the triterpenic acids in a binding pocket next to the catalytic site. An extensive hydrogen bond network with the carboxyl group and Van der Waals interactions stabilize the protein-ligand complexes.
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Affiliation(s)
- Juan José Ramírez-Espinosa
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Avenida Universidad 1001, Col. Chamilpa, Cuernavaca, Morelos 62209, Mexico
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32
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Ferrari E, Tinti M, Costa S, Corallino S, Nardozza AP, Chatraryamontri A, Ceol A, Cesareni G, Castagnoli L. Identification of new substrates of the protein-tyrosine phosphatase PTP1B by Bayesian integration of proteome evidence. J Biol Chem 2010; 286:4173-85. [PMID: 21123182 PMCID: PMC3039405 DOI: 10.1074/jbc.m110.157420] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
There is growing evidence that tyrosine phosphatases display an intrinsic enzymatic preference for the sequence context flanking the target phosphotyrosines. On the other hand, substrate selection in vivo is decisively guided by the enzyme-substrate connectivity in the protein interaction network. We describe here a system wide strategy to infer physiological substrates of protein-tyrosine phosphatases. Here we integrate, by a Bayesian model, proteome wide evidence about in vitro substrate preference, as determined by a novel high-density peptide chip technology, and “closeness” in the protein interaction network. This allows to rank candidate substrates of the human PTP1B phosphatase. Ultimately a variety of in vitro and in vivo approaches were used to verify the prediction that the tyrosine phosphorylation levels of five high-ranking substrates, PLC-γ1, Gab1, SHP2, EGFR, and SHP1, are indeed specifically modulated by PTP1B. In addition, we demonstrate that the PTP1B-mediated dephosphorylation of Gab1 negatively affects its EGF-induced association with the phosphatase SHP2. The dissociation of this signaling complex is accompanied by a decrease of ERK MAP kinase phosphorylation and activation.
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Affiliation(s)
- Emanuela Ferrari
- Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00144 Rome, Italy
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Stuible M, Tremblay ML. In control at the ER: PTP1B and the down-regulation of RTKs by dephosphorylation and endocytosis. Trends Cell Biol 2010; 20:672-9. [DOI: 10.1016/j.tcb.2010.08.013] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 08/10/2010] [Accepted: 08/25/2010] [Indexed: 01/26/2023]
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Yip SC, Saha S, Chernoff J. PTP1B: a double agent in metabolism and oncogenesis. Trends Biochem Sci 2010; 35:442-9. [PMID: 20381358 PMCID: PMC2917533 DOI: 10.1016/j.tibs.2010.03.004] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 03/02/2010] [Accepted: 03/05/2010] [Indexed: 01/17/2023]
Abstract
PTP1B, a non-transmembrane protein tyrosine phosphatase that has long been studied as a negative regulator of insulin and leptin signaling, has received renewed attention as an unexpected positive factor in tumorigenesis. Here, we highlight how views of this enzyme have evolved from regarding it as a simple metabolic off-switch to a more complex view of PTP1B as an enzyme that can play both negative and positive roles in diverse signaling pathways. These dual characteristics make PTP1B a particularly attractive therapeutic target for diabetes, obesity, and perhaps breast cancer.
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Affiliation(s)
- Shu-Chin Yip
- Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
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35
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Stuible M, Abella JV, Feldhammer M, Nossov M, Sangwan V, Blagoev B, Park M, Tremblay ML. PTP1B targets the endosomal sorting machinery: dephosphorylation of regulatory sites on the endosomal sorting complex required for transport component STAM2. J Biol Chem 2010; 285:23899-907. [PMID: 20504764 DOI: 10.1074/jbc.m110.115295] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dephosphorylation and endocytic down-regulation are distinct processes that together control the signaling output of a variety of receptor tyrosine kinases (RTKs). PTP1B can directly dephosphorylate several RTKs, but it can also promote activation of downstream pathways through largely unknown mechanisms. These positive signaling functions likely contribute to the tumor-promoting effect of PTP1B in mouse cancer models. Here, we have identified STAM2, an endosomal protein involved in sorting activated RTKs for lysosomal degradation, as a substrate of PTP1B. PTP1B interacts with STAM2 at defined phosphotyrosine sites, and knockdown of PTP1B expression augments STAM2 phosphorylation. Intriguingly, manipulating the expression and phosphorylation state of STAM2 did not have a general effect on epidermal growth factor (EGF)-induced EGF receptor trafficking, degradation, or signaling. Instead, phosphorylated STAM2 specifically suppressed Akt activation, and a phosphorylation-deficient STAM2 mutant displayed prolonged localization on endosomes following EGF stimulation. These results reveal a novel link between the dephosphorylation and endocytic machinery and suggest that PTP1B can affect RTK signaling in a previously unrecognized manner.
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Affiliation(s)
- Matthew Stuible
- Rosalind and Morris Goodman Cancer Centre and Departments of Biochemistry and Oncology, McGill University, Montreal, Quebec H3A 1A3, Canada
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36
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Hernández MV, Wehrendt DP, Arregui CO. The protein tyrosine phosphatase PTP1B is required for efficient delivery of N-cadherin to the cell surface. Mol Biol Cell 2010; 21:1387-97. [PMID: 20181825 PMCID: PMC2854096 DOI: 10.1091/mbc.e09-10-0880] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This work shows a novel role of PTP1B in the regulation of N-cadherin trafficking. PTP1B is required for the association of p120 to the N-cadherin precursor and this event is crucial for trafficking of the complex through the early stages of the secretory pathway. PTP1B bound to mature N-cadherin promotes the association of β-catenin into the complex, the stable expression of the complex at cell surface, and cadherin-mediated adhesion. Here we show that PTP1B is also required for N-cadherin precursor trafficking through early stages of the secretory pathway. This function does not require association of PTP1B with the precursor. In PTP1B null cells, the N-cadherin precursor showed higher sensitivity to endoglycosidase H than in cells reconstituted with the wild-type enzyme. It also showed slower kinetics of ER-to-Golgi translocation and processing. Trafficking of the viral stomatitis vesicular glycoprotein, VSV-G, however, revealed no differences between PTP1B null and reconstituted cells. N-cadherin precursor complexes contained similar levels of α- and β-catenin regardless of PTP1B expression. In contrast, the associated p120 catenin (p120) was significantly reduced in absence of PTP1B expression. An N-cadherin precursor construct defective in p120 binding, and expressed in PTP1B reconstituted cells, showed higher sensitivity to endoglycosidase H and slower kinetics of processing than the wild-type precursor. Our results suggest that PTP1B promotes the association of p120 to the N-cadherin precursor, facilitating the trafficking of the complex from the ER to the Golgi complex.
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Affiliation(s)
- Mariana V Hernández
- Instituto de Investigaciones Biotecnológicas (IIB-INTECH), Universidad de San Martín, 1650 San Martín, Buenos Aires, Argentina
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37
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Chacón PJ, Arévalo MA, Tébar AR. NGF-activated protein tyrosine phosphatase 1B mediates the phosphorylation and degradation of I-kappa-Balpha coupled to NF-kappa-B activation, thereby controlling dendrite morphology. Mol Cell Neurosci 2010; 43:384-93. [PMID: 20123020 DOI: 10.1016/j.mcn.2010.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 01/03/2010] [Accepted: 01/21/2010] [Indexed: 02/07/2023] Open
Abstract
NGF diminishes dendrite complexity in cultured hippocampal neurons by decreasing the number of primary and secondary dendrites, while increasing the length of those that remain. The transduction pathway used by NGF to provoke dendrite elongation involves the activation of NF-kappa-B and the expression of the homologues of Enhancer-of-split 1 gene. Here, we define important steps that link NGF with NF-kappa-B activation, through the activity of protein tyrosine phosphatase 1B (PTP1B). Binding of NGF to p75(NTR) stimulates PTP1B activity, which can be blocked by either pharmacological inhibition of the phosphatase or by transfecting neurons with a dn PTP1B isoform, whereby NGF is no longer able to stimulate dendrite growth. Indeed, overexpressing PTP1B alone provoked dendrite growth and further studies revealed a role for the src kinase downstream of PTP1B. Again, loss of src activity largely cancelled out the capacity of NGF to promote dendrite growth, whereas overexpression of v-src in neurons was sufficient to promote dendrite growth. Finally, the NGF/p75(NTR)/PTP1B/src kinase pathway led to the tyrosine phosphorylation of I-kappa-Balpha prior to its degradation, an event that is necessary for NF-kappa-B activation. Indeed, the dendrite growth response to NGF was lost when neurons were transfected with a mutant form of I-kappa-Balpha that lacks tyr42. Thus, our data suggest that PTP1B fulfils a central role in the NGF signalling that controls dendrite patterning in hippocampal neurons.
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Affiliation(s)
- Pedro J Chacón
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER/CSIC), Av. Americo Vespucio s/n, Isla de la Cartuja, 41092 Seville, Spain
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38
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Membrane contacts between endosomes and ER provide sites for PTP1B-epidermal growth factor receptor interaction. Nat Cell Biol 2010; 12:267-72. [PMID: 20118922 DOI: 10.1038/ncb2026] [Citation(s) in RCA: 244] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 01/17/2009] [Indexed: 01/13/2023]
Abstract
The epidermal growth factor receptor (EGFR) is a critical determinator of cell fate. Signalling from this receptor tyrosine kinase is spatially regulated by progression through the endocytic pathway, governing receptor half-life and accessibility to signalling proteins and phosphatases. Endocytosis of EGFR is required for interaction with the protein tyrosine phosphatase PTP1B (ref. 1), which localizes to the cytoplasmic face of the endoplasmic reticulum (ER), raising the question of how PTP1B comes into contact with endosomal EGFR. We show that EGFR-PTP1B interaction occurs by means of direct membrane contacts between the perimeter membrane of multivesicular bodies (MVBs) and the ER. The population of EGFR interacting with PTP1B is the same population that undergo ESCRT-mediated (endosomal sorting complex required for transport) sorting within MVBs, and PTP1B activity promotes the sequestration of EGFR on to MVB internal vesicles. Membrane contacts between endosomes and the ER form in both the presence and absence of stimulation by EGF. Thus membrane contacts between endosomes and the ER may represent a global mechanism for direct interaction between proteins on these two organelles.
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39
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Lessard L, Stuible M, Tremblay ML. The two faces of PTP1B in cancer. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1804:613-9. [PMID: 19782770 DOI: 10.1016/j.bbapap.2009.09.018] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 09/11/2009] [Accepted: 09/18/2009] [Indexed: 10/25/2022]
Abstract
PTP1B is a classical non-transmembrane protein tyrosine phosphatase that plays a key role in metabolic signaling and is a promising drug target for type 2 diabetes and obesity. Accumulating evidence also indicates that PTP1B is involved in cancer, but contrasting findings suggest that it can exert both tumor suppressing and tumor promoting effects depending on the substrate involved and the cellular context. In this review, we will discuss the diverse mechanisms by which PTP1B may influence tumorigenesis as well as recent in vivo data on the impact of PTP1B deficiency in murine cancer models. Together, these results highlight not only the great potential of PTP1B inhibitors in cancer therapy but also the need for a better understanding of PTP1B function prior to use of these compounds in human patients.
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Affiliation(s)
- Laurent Lessard
- Goodman Cancer Centre and Department of Biochemistry, McGill University, 1160 Pine Avenue, Montréal, Québec, Canada H3G 0B1
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40
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Fuentes F, Arregui CO. Microtubule and cell contact dependency of ER-bound PTP1B localization in growth cones. Mol Biol Cell 2009; 20:1878-89. [PMID: 19158394 DOI: 10.1091/mbc.e08-07-0675] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PTP1B is an ER-bound protein tyrosine phosphatase implied in the regulation of cell adhesion. Here we investigated mechanisms involved in the positioning and dynamics of PTP1B in axonal growth cones and evaluated the role of this enzyme in axons. In growth cones, PTP1B consistently localizes in the central domain, and occasionally at the peripheral region and filopodia. Live imaging of GFP-PTP1B reveals dynamic excursions of fingerlike processes within the peripheral region and filopodia. PTP1B and GFP-PTP1B colocalize with ER markers and coalign with microtubules at the peripheral region and redistribute to the base of the growth cone after treatment with nocodazole, a condition that is reversible. Growth cone contact with cellular targets is accompanied by invasion of PTP1B and stable microtubules in the peripheral region aligned with the contact axis. Functional impairment of PTP1B causes retardation of axon elongation, as well as reduction of growth cone filopodia lifetime and Src activity. Our results highlight the role of microtubules and cell contacts in the positioning of ER-bound PTP1B to the peripheral region of growth cones, which may be required for the positive role of PTP1B in axon elongation, filopodia stabilization, and Src activity.
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Affiliation(s)
- Federico Fuentes
- Instituto de Investigaciones Biotecnológicas, Universidad de San Martín, 1650 San Martín, Buenos Aires, Argentina
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41
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Li S, Depetris RS, Barford D, Chernoff J, Hubbard SR. Crystal structure of a complex between protein tyrosine phosphatase 1B and the insulin receptor tyrosine kinase. Structure 2008; 13:1643-51. [PMID: 16271887 DOI: 10.1016/j.str.2005.07.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 07/28/2005] [Accepted: 07/28/2005] [Indexed: 02/03/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a highly specific negative regulator of insulin receptor signaling in vivo. The determinants of PTP1B specificity for the insulin receptor versus other receptor tyrosine kinases are largely unknown. Here, we report a crystal structure at 2.3 A resolution of the catalytic domain of PTP1B (trapping mutant) in complex with the phosphorylated tyrosine kinase domain of the insulin receptor (IRK). The crystallographic asymmetric unit contains two PTP1B-IRK complexes that interact through an IRK dimer interface. Rather than binding to a phosphotyrosine in the IRK activation loop, PTP1B binds instead to the opposite side of the kinase domain, with the phosphorylated activation loops sequestered within the IRK dimer. The crystal structure provides evidence for a noncatalytic mode of interaction between PTP1B and IRK, which could be important for the selective recruitment of PTP1B to the insulin receptor.
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Affiliation(s)
- Shiqing Li
- Structural Biology Program, Skirball Institute of Biomolecular Medicine and Department of Pharmacology, New York University School of Medicine, New York, New York 10016, USA
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42
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Hussain M, Ahmed V, Hill B, Ahmed Z, Taylor SD. A re-examination of the difluoromethylenesulfonic acid group as a phosphotyrosine mimic for PTP1B inhibition. Bioorg Med Chem 2008; 16:6764-77. [DOI: 10.1016/j.bmc.2008.05.062] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Revised: 05/16/2008] [Accepted: 05/28/2008] [Indexed: 01/02/2023]
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43
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Stuible M, Doody KM, Tremblay ML. PTP1B and TC-PTP: regulators of transformation and tumorigenesis. Cancer Metastasis Rev 2008; 27:215-30. [DOI: 10.1007/s10555-008-9115-1] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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44
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Ruffolo SC, Forsell PKA, Yuan X, Desmarais S, Himms-Hagen J, Cromlish W, Wong KK, Kennedy BP. Basal Activation of p70S6K Results in Adipose-specific Insulin Resistance in Protein-tyrosine Phosphatase 1B–/– Mice. J Biol Chem 2007; 282:30423-33. [PMID: 17664276 DOI: 10.1074/jbc.m700697200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although protein-tyrosine phosphatase 1B (PTP-1B) is a negative regulator of insulin action, adipose tissue from PTP-1B-/- mice does not show enhanced insulin-stimulated insulin receptor phosphorylation. Investigation of glucose uptake in isolated adipocytes revealed that the adipocytes from PTP-1B-/- mice have a significantly attenuated insulin response as compared with PTP-1B+/+ adipocytes. This insulin resistance manifests in PTP-1B-/- animals older than 16 weeks of age and could be partially rescued by adenoviral expression of PTP-1B in null adipocytes. Examination of adipose signaling pathways found that the basal p70S6K activity was at least 50% higher in adipose from PTP-1B-/- mice compared with wild type animals. The increased basal activity of p70S6K in PTP-1B-/- adipose correlated with decreases in IR substrate-1 protein levels and insulin-stimulated Akt/protein kinase B activity, explaining the decrease in insulin sensitivity even as insulin receptor phosphorylation was unaffected. The insulin resistance of the of the PTP-1B-/- adipocytes could also be rescued by treatment with rapamycin, suggesting that in adipose the loss of PTP-1B results in basal activation of mTOR (mammalian target of rapamycin) complex 1 leading to a tissue-specific insulin resistance.
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Affiliation(s)
- Salvatore C Ruffolo
- Department of Biochemistry and Molecular Biology, Merck Frosst Centre for Therapeutic Research, Pointe-Claire-Dorval, Quebec, H9R 4P8, Canada
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45
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Romanelli RJ, LeBeau AP, Fulmer CG, Lazzarino DA, Hochberg A, Wood TL. Insulin-like Growth Factor Type-I Receptor Internalization and Recycling Mediate the Sustained Phosphorylation of Akt. J Biol Chem 2007; 282:22513-24. [PMID: 17545147 DOI: 10.1074/jbc.m704309200] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previously we demonstrated that insulin-like growth factor-I mediates the sustained phosphorylation of Akt, which is essential for long term survival and protection of glial progenitors from glutamate toxicity. These prosurvival effects correlated with prolonged activation and stability of the insulin-like growth factor type-I receptor. In the present study, we investigated the mechanisms whereby insulin-like growth factor-I signaling, through the insulin-like growth factor type-I receptor, mediates the sustained phosphorylation of Akt. We showed that insulin-like growth factor-I stimulation induced loss of receptors from the cell surface but that surface receptors recovered over time. Blocking receptor internalization inhibited Akt phosphorylation, whereas inhibition of receptor trafficking blocked receptor recovery at the cell surface and the sustained phosphorylation of Akt. Moreover the insulin-like growth factor type-I receptor localized with the transferrin receptor and Rab11-positive endosomes in a ligand-dependent manner, further supporting the conclusion that this receptor follows a recycling pathway. Our results provide evidence that ligand stimulation leads to internalization of the insulin-like growth factor type-I receptor, which mediates Akt phosphorylation, and that receptor recycling sustains Akt phosphorylation in glial progenitors. Mathematical modeling of receptor trafficking further supports these results and predicts an additional kinetic state of the receptor consistent with sustained Akt phosphorylation.
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Affiliation(s)
- Robert J Romanelli
- Department of Neurology and Neurosciences, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
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46
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Zarei MM, Song M, Wilson RJ, Cox N, Colom LV, Knaus HG, Stefani E, Toro L. Endocytic trafficking signals in KCNMB2 regulate surface expression of a large conductance voltage and Ca2+-activated K+ channel. Neuroscience 2007; 147:80-9. [PMID: 17521822 DOI: 10.1016/j.neuroscience.2007.04.019] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 04/05/2007] [Accepted: 04/06/2007] [Indexed: 11/22/2022]
Abstract
Large conductance voltage and calcium-activated K(+) channels play critical roles in neuronal excitability and vascular tone. Previously, we showed that coexpression of the transmembrane beta2 subunit, KCNMB2, with the human pore-forming alpha subunit of the large conductance voltage and Ca(2+)-activated K(+) channel (hSlo) yields inactivating currents similar to those observed in hippocampal neurons [Hicks GA, Marrion NV (1998) Ca(2+)-dependent inactivation of large conductance Ca(2+)-activated K(+) (BK) channels in rat hippocampal neurones produced by pore block from an associated particle. J Physiol (Lond) 508 (Pt 3):721-734; Wallner M, Meera P, Toro L (1999b) Molecular basis of fast inactivation in voltage and Ca(2+)-activated K(+) channels: A transmembrane beta-subunit homolog. Proc Natl Acad Sci U S A 96:4137-4142]. Herein, we report that coexpression of beta2 subunit with hSlo can also modulate hSlo surface expression levels in HEK293T cells. We found that, when expressed alone, beta2 subunit appears to reach the plasma membrane but also displays a distinct intracellular punctuated pattern that resembles endosomal compartments. beta2 Subunit coexpression with hSlo causes two biological effects: i) a shift of hSlo's intracellular expression pattern from a relatively diffuse to a distinct punctated cytoplasmic distribution overlapping beta2 expression; and ii) a decrease of hSlo surface expression that surpassed an observed small decrease in total hSlo expression levels. beta2 Site-directed mutagenesis studies revealed two putative endocytic signals at the C-terminus of beta2 that can control expression levels of hSlo. In contrast, a beta2 N-terminal consensus endocytic signal had no effect on hSlo expression levels. Thus, beta2 subunit not only can influence hSlo currents but also has the ability to limit hSlo surface expression levels via an endocytic mechanism. This new mode of beta2 modulation of hSlo may depend on particular coregulatory mechanisms in different cell types.
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Affiliation(s)
- M M Zarei
- Department of Anesthesiology, University of California-Los Angeles, Los Angeles, CA 90095, USA.
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47
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Irandoust MI, Aarts LHJ, Roovers O, Gits J, Erkeland SJ, Touw IP. Suppressor of cytokine signaling 3 controls lysosomal routing of G-CSF receptor. EMBO J 2007; 26:1782-93. [PMID: 17363902 PMCID: PMC1847666 DOI: 10.1038/sj.emboj.7601640] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Accepted: 01/31/2007] [Indexed: 01/03/2023] Open
Abstract
The hematopoietic system provides an attractive model for studying growth factor-controlled expansion and differentiation of cells in relation to receptor routing and its consequences for signal transduction. Suppressor of cytokine signaling (SOCS) proteins regulate receptor signaling partly via their ubiquitin ligase (E3)-recruiting SOCS box domain. Whether SOCS proteins affect signaling through modulating intracellular trafficking of receptors is unknown. Here, we show that a juxtamembrane lysine residue (K632) of the granulocyte colony-stimulating factor receptor (G-CSFR) plays a key role in receptor routing and demonstrate that the effects of SOCS3 on G-CSF signaling to a major extent depend on this lysine. Mutation of K632 causes accumulation of G-CSFR in early endosomes and leads to sustained activation of signal transducer and activator of transcription 5 and ERK, but not protein kinase B. Myeloid progenitors expressing G-CSFR mutants lacking K632 show a perturbed proliferation/differentiation balance in response to G-CSF. This is the first demonstration of SOCS-mediated ubiquitination and routing of a cytokine receptor and its impact on maintaining an appropriate signaling output.
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Affiliation(s)
- Mahban I Irandoust
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Lambertus H J Aarts
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Onno Roovers
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Judith Gits
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Stefan J Erkeland
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Ivo P Touw
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
- Department of Hematology, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands. Tel.: +31 1040 87837; Fax: +31 1040 89470; E-mail:
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48
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Yudushkin IA, Schleifenbaum A, Kinkhabwala A, Neel BG, Schultz C, Bastiaens PIH. Live-cell imaging of enzyme-substrate interaction reveals spatial regulation of PTP1B. Science 2007; 315:115-9. [PMID: 17204654 DOI: 10.1126/science.1134966] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Endoplasmic reticulum-localized protein-tyrosine phosphatase PTP1B terminates growth factor signal transduction by dephosphorylation of receptor tyrosine kinases (RTKs). But how PTP1B allows for RTK signaling in the cytoplasm is unclear. In order to test whether PTP1B activity is spatially regulated, we developed a method based on Förster resonant energy transfer for imaging enzyme-substrate (ES) intermediates in live cells. We observed the establishment of a steady-state ES gradient across the cell. This gradient exhibited robustness to cell-to-cell variability, growth factor activation, and RTK localization, which demonstrated spatial regulation of PTP1B activity. Such regulation may be important for generating distinct cellular environments that permit RTK signal transduction and that mediate its eventual termination.
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Affiliation(s)
- Ivan A Yudushkin
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, D-69117 Heidelberg, Germany
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49
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Picha KM, Patel SS, Mandiyan S, Koehn J, Wennogle LP. The role of the C-terminal domain of protein tyrosine phosphatase-1B in phosphatase activity and substrate binding. J Biol Chem 2006; 282:2911-7. [PMID: 17135270 DOI: 10.1074/jbc.m610096200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Protein tyrosine phosphatase 1B (PTP-1B) has been implicated in the regulation of the insulin receptor. Dephosphorylation of the insulin receptor results in decreased insulin signaling and thus decreased glucose uptake. PTP-1B-/- mice have increased insulin sensitivity and are resistant to weight gain when fed a high fat diet, validating PTP-1B as a potential target for the treatment of type 2 diabetes. Many groups throughout the world have been searching for selective inhibitors for PTP-1B, and most of them target inhibitors to PTP-1B-(1-298), the N-terminal catalytic domain of the enzyme. However, the C-terminal domain is quite large and could influence the activity of the enzyme. Using two constructs of PTP-1B and a phosphopeptide as substrate, steady state assays showed that the presence of the C-terminal domain decreased both the Km and the k(cat) 2-fold. Pre-steady state kinetic experiments showed that the presence of the C-terminal domain improved the affinity of the enzyme for a phosphopeptide 2-fold, primarily because the off-rate was slower. This suggests that the C-terminal domain of PTP-1B may contact the phosphopeptide in some manner, allowing it to remain at the active site longer. This could be useful when screening libraries of compounds for inhibitors of PTP-1B. A compound that is able to make contacts with the C-terminal domain of PTP-1B would not only have a modest improvement in affinity but may also provide for specificity over other phosphatases.
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Affiliation(s)
- Kristen M Picha
- Metabolic and Cardiovascular Diseases Research, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA
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50
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Cromlish WA, Tang M, Kyskan R, Tran L, Kennedy BP. PTP1B-dependent insulin receptor phosphorylation/residency in the endocytic recycling compartment of CHO-IR cells. Biochem Pharmacol 2006; 72:1279-92. [PMID: 16956584 DOI: 10.1016/j.bcp.2006.07.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Revised: 07/31/2006] [Accepted: 07/31/2006] [Indexed: 12/22/2022]
Abstract
Insulin binds to the alpha subunit of the insulin receptor (IR) on the cell surface. The insulin-IR complex is subsequently internalized and trafficked within the cell. Endocytosed receptors, devoid of insulin, recycle back to the plasma membrane through the endocytic recycling compartment (ERC). Using a high content screening system, we investigate the intracellular trafficking of the IR and its phosphorylation state, within the ERC, in response to protein tyrosine phosphatase-1B (PTP1B) inhibition. Insulin stimulates, in a time- and dose-dependent manner, the accumulation of phosphorylated IR (pY(1158,1162,1163 IR) in the ERC of CHO-IR cells. Treatment of CHO-IR cells with PTP1B-specific inhibitors or siRNA leads to dose-dependent increases in IR residency and phosphorylation within the ERC. The results also demonstrate that PTP1B redistributes within CHO-IR cells upon insulin challenge. The established system will allow for efficient screening of candidate inhibitors for the modulation of PTP1B activity.
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Affiliation(s)
- Wanda A Cromlish
- Department of Biochemistry & Molecular Biology, Merck Frosst Centre for Therapeutic Research, Pointe-Claire-Dorval, Pointe-Claire-Dorval, Quebec, Canada.
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