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Cutler HB, Madsen S, Masson SWC, Cooke KC, Potter M, Burchfield JG, Stöckli J, Nelson ME, Cooney GJ, James DE. Dual Tracer Test to Measure Tissue-Specific Insulin Action in Individual Mice Identifies In Vivo Insulin Resistance Without Fasting Hyperinsulinemia. Diabetes 2024; 73:359-373. [PMID: 37699358 PMCID: PMC10882155 DOI: 10.2337/db23-0035] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 08/30/2023] [Indexed: 09/14/2023]
Abstract
The ability of metabolically active tissues to increase glucose uptake in response to insulin is critical to whole-body glucose homeostasis. This report describes the Dual Tracer Test, a robust method involving sequential retro-orbital injection of [14C]2-deoxyglucose ([14C]2DG) alone, followed 40 min later by injection of [3H]2DG with a maximal dose of insulin to quantify both basal and insulin-stimulated 2DG uptake in the same mouse. The collection of both basal and insulin-stimulated measures from a single animal is imperative for generating high-quality data since differences in insulin action may be misinterpreted mechanistically if basal glucose uptake is not accounted for. The approach was validated in a classic diet-induced model of insulin resistance and a novel transgenic mouse with reduced GLUT4 expression that, despite ubiquitous peripheral insulin resistance, did not exhibit fasting hyperinsulinemia. This suggests that reduced insulin-stimulated glucose disposal is not a primary contributor to chronic hyperinsulinemia. The Dual Tracer Test offers a technically simple assay that enables the study of insulin action in many tissues simultaneously. By administering two tracers and accounting for both basal and insulin-stimulated glucose transport, this assay halves the required sample size for studies in inbred mice and demonstrates increased statistical power to detect insulin resistance, relative to other established approaches, using a single tracer. The Dual Tracer Test is a valuable addition to the metabolic phenotyping toolbox. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Harry B Cutler
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Søren Madsen
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Stewart W C Masson
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Kristen C Cooke
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Meg Potter
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - James G Burchfield
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Jacqueline Stöckli
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Marin E Nelson
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Gregory J Cooney
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, Australia
| | - David E James
- School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, Australia
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2
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Diaz-Vegas A, Norris DM, Jall-Rogg S, Cooke KC, Conway OJ, Shun-Shion AS, Duan X, Potter M, van Gerwen J, Baird HJ, Humphrey SJ, James DE, Fazakerley DJ, Burchfield JG. A high-content endogenous GLUT4 trafficking assay reveals new aspects of adipocyte biology. Life Sci Alliance 2023; 6:e202201585. [PMID: 36283703 PMCID: PMC9595207 DOI: 10.26508/lsa.202201585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/10/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Insulin-induced GLUT4 translocation to the plasma membrane in muscle and adipocytes is crucial for whole-body glucose homeostasis. Currently, GLUT4 trafficking assays rely on overexpression of tagged GLUT4. Here we describe a high-content imaging platform for studying endogenous GLUT4 translocation in intact adipocytes. This method enables high fidelity analysis of GLUT4 responses to specific perturbations, multiplexing of other trafficking proteins and other features including lipid droplet morphology. Using this multiplexed approach we showed that Vps45 and Rab14 are selective regulators of GLUT4, but Trarg1, Stx6, Stx16, Tbc1d4 and Rab10 knockdown affected both GLUT4 and TfR translocation. Thus, GLUT4 and TfR translocation machinery likely have some overlap upon insulin-stimulation. In addition, we identified Kif13A, a Rab10 binding molecular motor, as a novel regulator of GLUT4 traffic. Finally, comparison of endogenous to overexpressed GLUT4 highlights that the endogenous GLUT4 methodology has an enhanced sensitivity to genetic perturbations and emphasises the advantage of studying endogenous protein trafficking for drug discovery and genetic analysis of insulin action in relevant cell types.
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Affiliation(s)
- Alexis Diaz-Vegas
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Dougall M Norris
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Sigrid Jall-Rogg
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Kristen C Cooke
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Olivia J Conway
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Amber S Shun-Shion
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Xiaowen Duan
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Meg Potter
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Julian van Gerwen
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Harry Jm Baird
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Sean J Humphrey
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
- School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Daniel J Fazakerley
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - James G Burchfield
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
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3
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Cocaine-regulated trafficking of dopamine transporters in cultured neurons revealed by a pH sensitive reporter. iScience 2022; 26:105782. [PMID: 36594015 PMCID: PMC9804146 DOI: 10.1016/j.isci.2022.105782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/07/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Cocaine acts by inhibiting plasma membrane dopamine transporter (DAT) function and altering its surface expression. The precise manner and mechanism by which cocaine regulates DAT trafficking, especially at neuronal processes, are poorly understood. In this study, we engineered and validated the use of DAT-pHluorin for studying DAT localization and its dynamic trafficking at neuronal processes of cultured mouse midbrain neurons. We demonstrate that unlike neuronal soma and dendrites, which contain a majority of the DATs in weakly acidic intracellular compartments, axonal DATs at both shafts and boutons are primarily (75%) localized to the plasma membrane, whereas large varicosities contain abundant intracellular DAT within acidic intracellular structures. We also demonstrate that cocaine exposure leads to a Synaptojanin1-sensitive DAT internalization process followed by membrane reinsertion that lasts for days. Thus, our study reveals the previously unknown dynamics and molecular regulation for cocaine-regulated DAT trafficking in neuronal processes.
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4
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Fazakerley DJ, Koumanov F, Holman GD. GLUT4 On the move. Biochem J 2022; 479:445-462. [PMID: 35147164 PMCID: PMC8883492 DOI: 10.1042/bcj20210073] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 12/16/2022]
Abstract
Insulin rapidly stimulates GLUT4 translocation and glucose transport in fat and muscle cells. Signals from the occupied insulin receptor are translated into downstream signalling changes in serine/threonine kinases within timescales of seconds, and this is followed by delivery and accumulation of the glucose transporter GLUT4 at the plasma membrane. Kinetic studies have led to realisation that there are distinct phases of this stimulation by insulin. There is a rapid initial burst of GLUT4 delivered to the cell surface from a subcellular reservoir compartment and this is followed by a steady-state level of continuing stimulation in which GLUT4 recycles through a large itinerary of subcellular locations. Here, we provide an overview of the phases of insulin stimulation of GLUT4 translocation and the molecules that are currently considered to activate these trafficking steps. Furthermore, we suggest how use of new experimental approaches together with phospho-proteomic data may help to further identify mechanisms for activation of these trafficking processes.
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Affiliation(s)
- Daniel J Fazakerley
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Francoise Koumanov
- Department for Health, Centre for Nutrition, Exercise, and Metabolism, University of Bath, Bath, Somerset BA2 7AY, U.K
| | - Geoffrey D Holman
- Department of Biology and Biochemistry, University of Bath, Bath, Somerset BA2 7AY, U.K
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5
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Heckmann M, Klanert G, Sandner G, Lanzerstorfer P, Auer M, Weghuber J. Fluorescence Microscopy-Based Quantitation of GLUT4 Translocation. Methods Appl Fluoresc 2022; 10. [PMID: 35008072 DOI: 10.1088/2050-6120/ac4998] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 01/10/2022] [Indexed: 11/11/2022]
Abstract
Postprandial insulin-stimulated glucose uptake into target tissue is crucial for the maintenance of normal blood glucose homeostasis. This step is rate-limited by the number of facilitative glucose transporters type 4 (GLUT4) present in the plasma membrane. Since insulin resistance and impaired GLUT4 translocation are associated with the development of metabolic disorders such as type 2 diabetes, this transporter has become an important target of antidiabetic drug research. The application of screening approaches that are based on the analysis of GLUT4 translocation to the plasma membrane to identify substances with insulinomimetic properties has gained global research interest in recent years. Here, we review methods that have been implemented to quantitate the translocation of GLUT4 to the plasma membrane. These methods can be broadly divided into two sections: microscopy-based technologies (e.g., immunoelectron, confocal or total internal reflection fluorescence microscopy) and biochemical and spectrometric approaches (e.g., membrane fractionation, photoaffinity labeling or flow cytometry). In this review, we discuss the most relevant approaches applied to GLUT4 thus far, highlighting the advantages and disadvantages of these approaches, and we provide a critical discussion and outlook into new methodological opportunities.
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Affiliation(s)
- Mara Heckmann
- University of Applied Sciences Upper Austria, Stelzhamerstrasse 23, Wels, Oberösterreich, 4600, AUSTRIA
| | - Gerald Klanert
- FFoQSI GmbH-Austrian Competence Centre for Feed and Food Quality, Safety and Innovation, Technopark 1C, Tulln, 3430, AUSTRIA
| | - Georg Sandner
- University of Applied Sciences Upper Austria, Stelzhamerstrasse 23, Wels, Oberösterreich, 4600, AUSTRIA
| | - Peter Lanzerstorfer
- University of Applied Sciences Upper Austria, Stelzhamerstrasse 23, Wels, Oberösterreich, 4600, AUSTRIA
| | - Manfred Auer
- Division of Pathway Medicine, University of Edinburgh, University of Edinburgh Medical School, The Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, Edinburgh, EH8 9AB, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND
| | - Julian Weghuber
- University of Applied Sciences Upper Austria, Stelzhamerstrasse 23, Wels, Oberösterreich, 4600, AUSTRIA
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6
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Batty SR, Langlais PR. Microtubules in insulin action: what's on the tube? Trends Endocrinol Metab 2021; 32:776-789. [PMID: 34462181 PMCID: PMC8446328 DOI: 10.1016/j.tem.2021.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022]
Abstract
Microtubules (MT) have a role in the intracellular response to insulin stimulation and subsequent glucose transport by glucose transporter 4 (GLUT4), which resides in specialized storage vesicles that travel through the cell. Before GLUT4 is inserted into the plasma membrane for glucose transport, it undergoes complex trafficking through the cell via the integration of cytoskeletal networks. In this review, we highlight the importance of MT elements in insulin action in adipocytes through a summary of MT depolymerization studies, MT-based GLUT4 movement, molecular motor proteins involved in GLUT4 trafficking, as well as MT-related phenomena in response to insulin and links between insulin action and MT-associated proteins.
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Affiliation(s)
- Skylar R Batty
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
| | - Paul R Langlais
- Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, AZ, USA.
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7
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Norris D, Yang P, Shin SY, Kearney AL, Kim HJ, Geddes T, Senior AM, Fazakerley DJ, Nguyen LK, James DE, Burchfield JG. Signaling Heterogeneity is Defined by Pathway Architecture and Intercellular Variability in Protein Expression. iScience 2021; 24:102118. [PMID: 33659881 PMCID: PMC7892930 DOI: 10.1016/j.isci.2021.102118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/07/2021] [Accepted: 01/22/2021] [Indexed: 12/12/2022] Open
Abstract
Insulin's activation of PI3K/Akt signaling, stimulates glucose uptake by enhancing delivery of GLUT4 to the cell surface. Here we examined the origins of intercellular heterogeneity in insulin signaling. Akt activation alone accounted for ~25% of the variance in GLUT4, indicating that additional sources of variance exist. The Akt and GLUT4 responses were highly reproducible within the same cell, suggesting the variance is between cells (extrinsic) and not within cells (intrinsic). Generalized mechanistic models (supported by experimental observations) demonstrated that the correlation between the steady-state levels of two measured signaling processes decreases with increasing distance from each other and that intercellular variation in protein expression (as an example of extrinsic variance) is sufficient to account for the variance in and between Akt and GLUT4. Thus, the response of a population to insulin signaling is underpinned by considerable single-cell heterogeneity that is largely driven by variance in gene/protein expression between cells. Insulin signaling is heterogeneous between cells in the same population The temporal response of signaling components within a cell is highly reproducible Upstream responses (Akt) can only partially predict downstream response (GLUT4) Protein expression variance is a driver of intercellular signaling heterogeneity
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Affiliation(s)
- Dougall Norris
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Pengyi Yang
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia.,Computational Systems Biology Group, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - Sung-Young Shin
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia.,Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Alison L Kearney
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Hani Jieun Kim
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia.,Computational Systems Biology Group, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - Thomas Geddes
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia.,Computational Systems Biology Group, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - Alistair M Senior
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Daniel J Fazakerley
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia
| | - Lan K Nguyen
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia.,Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - David E James
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.,Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia
| | - James G Burchfield
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
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8
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Quek LE, Krycer JR, Ohno S, Yugi K, Fazakerley DJ, Scalzo R, Elkington SD, Dai Z, Hirayama A, Ikeda S, Shoji F, Suzuki K, Locasale JW, Soga T, James DE, Kuroda S. Dynamic 13C Flux Analysis Captures the Reorganization of Adipocyte Glucose Metabolism in Response to Insulin. iScience 2020; 23:100855. [PMID: 32058966 PMCID: PMC7005519 DOI: 10.1016/j.isci.2020.100855] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/26/2019] [Accepted: 01/15/2020] [Indexed: 12/22/2022] Open
Abstract
Cellular metabolism is dynamic, but quantifying non-steady metabolic fluxes by stable isotope tracers presents unique computational challenges. Here, we developed an efficient 13C-tracer dynamic metabolic flux analysis (13C-DMFA) framework for modeling central carbon fluxes that vary over time. We used B-splines to generalize the flux parameterization system and to improve the stability of the optimization algorithm. As proof of concept, we investigated how 3T3-L1 cultured adipocytes acutely metabolize glucose in response to insulin. Insulin rapidly stimulates glucose uptake, but intracellular pathways responded with differing speeds and magnitudes. Fluxes in lower glycolysis increased faster than those in upper glycolysis. Glycolysis fluxes rose disproportionally larger and faster than the tricarboxylic acid cycle, with lactate a primary glucose end product. The uncovered array of flux dynamics suggests that glucose catabolism is additionally regulated beyond uptake to help shunt glucose into appropriate pathways. This work demonstrates the value of using dynamic intracellular fluxes to understand metabolic function and pathway regulation.
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Affiliation(s)
- Lake-Ee Quek
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia; School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia.
| | - James R Krycer
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Satoshi Ohno
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Katsuyuki Yugi
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan; Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; YCI Laboratory for Trans-Omics, Young Chief Investigator Program, RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Daniel J Fazakerley
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Richard Scalzo
- Faculty of Engineering and Information Technologies, The University of Sydney, Sydney, NSW 2006, Australia
| | - Sarah D Elkington
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Ziwei Dai
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Duke University, Durham, NC 27710, USA
| | - Akiyoshi Hirayama
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; AMED-CREST, AMED, 1-7-1 Otemachi, Chiyoda-Ku, Tokyo 100-0004, Japan
| | - Satsuki Ikeda
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan
| | - Futaba Shoji
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan
| | - Kumi Suzuki
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan
| | - Jason W Locasale
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Duke University, Durham, NC 27710, USA
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; AMED-CREST, AMED, 1-7-1 Otemachi, Chiyoda-Ku, Tokyo 100-0004, Japan
| | - David E James
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia; Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Shinya Kuroda
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan; CREST, Japan Science and Technology Agency, Bunkyo-ku, Tokyo 113-0033, Japan.
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9
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Kearney AL, Cooke KC, Norris DM, Zadoorian A, Krycer JR, Fazakerley DJ, Burchfield JG, James DE. Serine 474 phosphorylation is essential for maximal Akt2 kinase activity in adipocytes. J Biol Chem 2019; 294:16729-16739. [PMID: 31548312 DOI: 10.1074/jbc.ra119.010036] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/15/2019] [Indexed: 01/06/2023] Open
Abstract
The Ser/Thr protein kinase Akt regulates essential biological processes such as cell survival, growth, and metabolism. Upon growth factor stimulation, Akt is phosphorylated at Ser474; however, how this phosphorylation contributes to Akt activation remains controversial. Previous studies, which induced loss of Ser474 phosphorylation by ablating its upstream kinase mTORC2, have implicated Ser474 phosphorylation as a driver of Akt substrate specificity. Here we directly studied the role of Akt2 Ser474 phosphorylation in 3T3-L1 adipocytes by preventing Ser474 phosphorylation without perturbing mTORC2 activity. This was achieved by utilizing a chemical genetics approach, where ectopically expressed S474A Akt2 was engineered with a W80A mutation to confer resistance to the Akt inhibitor MK2206, and thus allow its activation independent of endogenous Akt. We found that insulin-stimulated phosphorylation of four bona fide Akt substrates (TSC2, PRAS40, FOXO1/3a, and AS160) was reduced by ∼50% in the absence of Ser474 phosphorylation. Accordingly, insulin-stimulated mTORC1 activation, protein synthesis, FOXO nuclear exclusion, GLUT4 translocation, and glucose uptake were attenuated upon loss of Ser474 phosphorylation. We propose a model where Ser474 phosphorylation is required for maximal Akt2 kinase activity in adipocytes.
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Affiliation(s)
- Alison L Kearney
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Kristen C Cooke
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Dougall M Norris
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Armella Zadoorian
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - James R Krycer
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Daniel J Fazakerley
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - James G Burchfield
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia .,Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia
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10
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Lu Y, Ma X, Kong Q, Xu Y, Hu J, Wang F, Qin W, Wang L, Xiong W. Novel dual-color drug screening model for GLUT4 translocation in adipocytes. Mol Cell Probes 2019; 43:6-12. [PMID: 30639558 DOI: 10.1016/j.mcp.2019.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 01/09/2019] [Accepted: 01/09/2019] [Indexed: 12/22/2022]
Abstract
Insulin-responsive glucose transporter type 4 (GLUT4) translocation plays a major role in controlling glucose uptake in adipose tissue and muscle, maintaining homeostasis and preventing hyperglycemia. Screening for chemicals enhancing GLUT4 translocation is an approach for identifying hits of drug development for type 2 diabetes. Here we developed a novel functional dual-color probe, pHluorin-GLUT4-mOrange2, and constructed 3T3-L1 adipocytes based screening system to simply and efficiently screen new compounds stimulating GLUT4 translocation. Based on this system, we successfully identified a few hits facilitating GLUT4 translocation. In conclusion, we developed an easy-to-apply dual color GLUT4 probe to monitor GLUT4 translocation in insulin-responsive cells, which could be alternatively employed to high-throughput screen compounds regulating GLUT4 translocation and glucose uptake, even to dissect GLTU4 approaching, docking and fusion with the plasma membrane (PM), and to reveal relevant molecular mechanisms involved in these steps as expected.
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Affiliation(s)
- Yanting Lu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiuli Ma
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Qinghua Kong
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Yuhui Xu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Jing Hu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Fang Wang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Wanying Qin
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Libin Wang
- The General Hospital of Ningxia Medical University, Department of Beijing National Biochip Research Center Sub-Center in Ningxia, Yinchuan, 750004, China.
| | - Wenyong Xiong
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; The General Hospital of Ningxia Medical University, Department of Beijing National Biochip Research Center Sub-Center in Ningxia, Yinchuan, 750004, China.
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11
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McCormick CD, Waters HN, Bezrukov L, Taginya R, Parikh V, Onyekaba GI, Levine JA, Demidowich AP, Yanovski JA, Blank PS, Zimmerberg J. Subcutaneous adipose tissue imaging of human obesity reveals two types of adipocyte membranes: Insulin-responsive and -nonresponsive. J Biol Chem 2018; 293:14249-14259. [PMID: 30006347 DOI: 10.1074/jbc.ra118.003751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/28/2018] [Indexed: 11/06/2022] Open
Abstract
In adipose tissue, resistance to insulin's ability to increase glucose uptake can be induced by multiple factors, including obesity. Impaired insulin action may take place at different spatial loci at the cellular or subcellular level. To begin to understand the spatial response to insulin in human subcutaneous adipose tissue (hSAT), we developed a quantitative imaging method for activation of a major signaling node in the glucoregulatory insulin signaling pathway. After treatment with insulin or control media, biopsied tissues were immunostained for Akt phosphorylation at Thr-308/9 (pAkt) and then imaged by confocal fluorescence microscopy automated to collect a large grid of high resolution fields. In hSAT from 40 men and women with obesity, substantial heterogeneity of pAkt densities in adipocyte membranes were quantified in each image mosaic using a spatial unit of at least twice the size of the point spread function. Statistical analysis of the distribution of pAkt spatial units was best fit as the weighted sum of two separate distributions, corresponding to either a low or high pAkt density. A "high pAkt fraction" metric was calculated from the fraction of high pAkt distributed units over the total units. Importantly, upon insulin stimulation, tissues from the same biopsy showed either a minimal or a substantial change in the high pAkt fraction. Further supporting a two-state response to insulin stimulation, subjects with similar insulin sensitivity indices are also segregated into either of two clusters identified by the amount of membrane-localized pAkt.
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Affiliation(s)
| | | | | | | | - Viraj Parikh
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Ginikanwa I Onyekaba
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Jordan A Levine
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Andrew P Demidowich
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Jack A Yanovski
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
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12
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Fazakerley DJ, Minard AY, Krycer JR, Thomas KC, Stöckli J, Harney DJ, Burchfield JG, Maghzal GJ, Caldwell ST, Hartley RC, Stocker R, Murphy MP, James DE. Mitochondrial oxidative stress causes insulin resistance without disrupting oxidative phosphorylation. J Biol Chem 2018; 293:7315-7328. [PMID: 29599292 PMCID: PMC5950018 DOI: 10.1074/jbc.ra117.001254] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/19/2018] [Indexed: 01/02/2023] Open
Abstract
Mitochondrial oxidative stress, mitochondrial dysfunction, or both have been implicated in insulin resistance. However, disentangling the individual roles of these processes in insulin resistance has been difficult because they often occur in tandem, and tools that selectively increase oxidant production without impairing mitochondrial respiration have been lacking. Using the dimer/monomer status of peroxiredoxin isoforms as an indicator of compartmental hydrogen peroxide burden, we provide evidence that oxidative stress is localized to mitochondria in insulin-resistant 3T3-L1 adipocytes and adipose tissue from mice. To dissociate oxidative stress from impaired oxidative phosphorylation and study whether mitochondrial oxidative stress per se can cause insulin resistance, we used mitochondria-targeted paraquat (MitoPQ) to generate superoxide within mitochondria without directly disrupting the respiratory chain. At ≤10 μm, MitoPQ specifically increased mitochondrial superoxide and hydrogen peroxide without altering mitochondrial respiration in intact cells. Under these conditions, MitoPQ impaired insulin-stimulated glucose uptake and glucose transporter 4 (GLUT4) translocation to the plasma membrane in both adipocytes and myotubes. MitoPQ recapitulated many features of insulin resistance found in other experimental models, including increased oxidants in mitochondria but not cytosol; a more profound effect on glucose transport than on other insulin-regulated processes, such as protein synthesis and lipolysis; an absence of overt defects in insulin signaling; and defective insulin- but not AMP-activated protein kinase (AMPK)-regulated GLUT4 translocation. We conclude that elevated mitochondrial oxidants rapidly impair insulin-regulated GLUT4 translocation and significantly contribute to insulin resistance and that MitoPQ is an ideal tool for studying the link between mitochondrial oxidative stress and regulated GLUT4 trafficking.
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Affiliation(s)
- Daniel J Fazakerley
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - Annabel Y Minard
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - James R Krycer
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - Kristen C Thomas
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - Jacqueline Stöckli
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - Dylan J Harney
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - James G Burchfield
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia
| | - Ghassan J Maghzal
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Stuart T Caldwell
- School of Chemistry, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Richard C Hartley
- School of Chemistry, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Roland Stocker
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, Hills Road, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences, Camperdown, New South Wales 2006, Australia; Charles Perkins Centre, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006, Australia.
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13
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Burchfield JG, Kebede MA, Meoli CC, Stöckli J, Whitworth PT, Wright AL, Hoffman NJ, Minard AY, Ma X, Krycer JR, Nelson ME, Tan SX, Yau B, Thomas KC, Wee NKY, Khor EC, Enriquez RF, Vissel B, Biden TJ, Baldock PA, Hoehn KL, Cantley J, Cooney GJ, James DE, Fazakerley DJ. High dietary fat and sucrose results in an extensive and time-dependent deterioration in health of multiple physiological systems in mice. J Biol Chem 2018; 293:5731-5745. [PMID: 29440390 DOI: 10.1074/jbc.ra117.000808] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/12/2018] [Indexed: 01/17/2023] Open
Abstract
Obesity is associated with metabolic dysfunction, including insulin resistance and hyperinsulinemia, and with disorders such as cardiovascular disease, osteoporosis, and neurodegeneration. Typically, these pathologies are examined in discrete model systems and with limited temporal resolution, and whether these disorders co-occur is therefore unclear. To address this question, here we examined multiple physiological systems in male C57BL/6J mice following prolonged exposure to a high-fat/high-sucrose diet (HFHSD). HFHSD-fed mice rapidly exhibited metabolic alterations, including obesity, hyperleptinemia, physical inactivity, glucose intolerance, peripheral insulin resistance, fasting hyperglycemia, ectopic lipid deposition, and bone deterioration. Prolonged exposure to HFHSD resulted in morbid obesity, ectopic triglyceride deposition in liver and muscle, extensive bone loss, sarcopenia, hyperinsulinemia, and impaired short-term memory. Although many of these defects are typically associated with aging, HFHSD did not alter telomere length in white blood cells, indicating that this diet did not generally promote all aspects of aging. Strikingly, glucose homeostasis was highly dynamic. Glucose intolerance was evident in HFHSD-fed mice after 1 week and was maintained for 24 weeks. Beyond 24 weeks, however, glucose tolerance improved in HFHSD-fed mice, and by 60 weeks, it was indistinguishable from that of chow-fed mice. This improvement coincided with adaptive β-cell hyperplasia and hyperinsulinemia, without changes in insulin sensitivity in muscle or adipose tissue. Assessment of insulin secretion in isolated islets revealed that leptin, which inhibited insulin secretion in the chow-fed mice, potentiated glucose-stimulated insulin secretion in the HFHSD-fed mice after 60 weeks. Overall, the excessive calorie intake was accompanied by deteriorating function of numerous physiological systems.
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Affiliation(s)
- James G Burchfield
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Melkam A Kebede
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia
| | - Christopher C Meoli
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Jacqueline Stöckli
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - P Tess Whitworth
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Amanda L Wright
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Nolan J Hoffman
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Annabel Y Minard
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Xiuquan Ma
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - James R Krycer
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Marin E Nelson
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia
| | - Shi-Xiong Tan
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Belinda Yau
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia
| | - Kristen C Thomas
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Natalie K Y Wee
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Ee-Cheng Khor
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Ronaldo F Enriquez
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Bryce Vissel
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Trevor J Biden
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Paul A Baldock
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Kyle L Hoehn
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - James Cantley
- Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
| | - Gregory J Cooney
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Charles Perkins Centre, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006, Australia
| | - David E James
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia, .,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and.,Charles Perkins Centre, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006, Australia
| | - Daniel J Fazakerley
- From the Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Camperdown, New South Wales 2006, Australia.,Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, and
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14
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Norris DM, Geddes TA, James DE, Fazakerley DJ, Burchfield JG. Glucose Transport: Methods for Interrogating GLUT4 Trafficking in Adipocytes. Methods Mol Biol 2018; 1713:193-215. [PMID: 29218527 DOI: 10.1007/978-1-4939-7507-5_15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this chapter we detail methods for the systematic dissection of GLUT4 trafficking. The methods described have been optimized for cultured 3T3-L1 adipocytes, but can be readily adapted to other cell types.
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Affiliation(s)
- Dougall M Norris
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- The Charles Perkins Centre, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Tom A Geddes
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- The Charles Perkins Centre, The University of Sydney, Sydney, 2006, NSW, Australia
| | - David E James
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia
- The Charles Perkins Centre, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Daniel J Fazakerley
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- The Charles Perkins Centre, The University of Sydney, Sydney, 2006, NSW, Australia
| | - James G Burchfield
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia.
- The Charles Perkins Centre, The University of Sydney, Sydney, 2006, NSW, Australia.
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15
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Wasserstrom S, Morén B, Stenkula KG. Total Internal Reflection Fluorescence Microscopy to Study GLUT4 Trafficking. Methods Mol Biol 2018; 1713:151-159. [PMID: 29218524 DOI: 10.1007/978-1-4939-7507-5_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Total internal reflection fluorescence (TIRF) microscopy is a powerful method that allows examination of plasma membrane close events in real time. The last decade, the method has successfully been used to explore GLUT4 translocation in adipocytes. Here, we describe the procedure for studying GLUT4 trafficking using TIRF microscopy in isolated primary adipocytes.
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Affiliation(s)
- Sebastian Wasserstrom
- Department of Experimental Medical Science, Lund University, BMC C11, Lund, 22 184, Sweden
| | - Björn Morén
- Department of Experimental Medical Science, Lund University, BMC C11, Lund, 22 184, Sweden
| | - Karin G Stenkula
- Department of Experimental Medical Science, Lund University, BMC C11, Lund, 22 184, Sweden.
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16
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Norris DM, Yang P, Krycer JR, Fazakerley DJ, James DE, Burchfield JG. An improved Akt reporter reveals intra- and inter-cellular heterogeneity and oscillations in signal transduction. J Cell Sci 2017; 130:2757-2766. [PMID: 28663386 DOI: 10.1242/jcs.205369] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/26/2017] [Indexed: 11/20/2022] Open
Abstract
Akt is a key node in a range of signal transduction cascades and play a critical role in diseases such as cancer and diabetes. Fluorescently-tagged Akt reporters have been used to discern Akt localisation, yet it has not been clear how well these tools recapitulate the behaviour of endogenous Akt proteins. Here, we observed that fusion of eGFP to Akt2 impaired both its insulin-stimulated plasma membrane recruitment and its phosphorylation. Endogenous-like responses were restored by replacing eGFP with TagRFP-T. The improved response magnitude and sensitivity afforded by TagRFP-T-Akt2 over eGFP-Akt2 enabled monitoring of signalling outcomes in single cells at physiological doses of insulin with subcellular resolution and revealed two previously unreported features of Akt biology. In 3T3-L1 adipocytes, stimulation with insulin resulted in recruitment of Akt2 to the plasma membrane in a polarised fashion. Additionally, we observed oscillations in plasma membrane localised Akt2 in the presence of insulin with a consistent periodicity of 2 min. Our studies highlight the importance of fluorophore choice when generating reporter constructs and shed light on new Akt signalling responses that may encode complex signalling information.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Dougall M Norris
- Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Pengyi Yang
- Charles Perkins Centre, School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia
| | - James R Krycer
- Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Daniel J Fazakerley
- Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.,Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia
| | - James G Burchfield
- Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
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17
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GLUT4 Mobilization Supports Energetic Demands of Active Synapses. Neuron 2017; 93:606-615.e3. [PMID: 28111082 DOI: 10.1016/j.neuron.2016.12.020] [Citation(s) in RCA: 201] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/08/2016] [Accepted: 12/15/2016] [Indexed: 12/19/2022]
Abstract
The brain is highly sensitive to proper fuel availability as evidenced by the rapid decline in neuronal function during ischemic attacks and acute severe hypoglycemia. We previously showed that sustained presynaptic function requires activity-driven glycolysis. Here, we provide strong evidence that during action potential (AP) firing, nerve terminals rely on the glucose transporter GLUT4 as a glycolytic regulatory system to meet the activity-driven increase in energy demands. Activity at synapses triggers insertion of GLUT4 into the axonal plasma membrane driven by activation of the metabolic sensor AMP kinase. Furthermore, we show that genetic ablation of GLUT4 leads to an arrest of synaptic vesicle recycling during sustained AP firing, similar to what is observed during acute glucose deprivation. The reliance on this biochemical regulatory system for "exercising" synapses is reminiscent of that occurring in exercising muscle to sustain cellular function and identifies nerve terminals as critical sites of proper metabolic control.
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18
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Fazakerley DJ, Naghiloo S, Chaudhuri R, Koumanov F, Burchfield JG, Thomas KC, Krycer JR, Prior MJ, Parker BL, Murrow BA, Stöckli J, Meoli CC, Holman GD, James DE. Proteomic Analysis of GLUT4 Storage Vesicles Reveals Tumor Suppressor Candidate 5 (TUSC5) as a Novel Regulator of Insulin Action in Adipocytes. J Biol Chem 2015; 290:23528-42. [PMID: 26240143 PMCID: PMC4583025 DOI: 10.1074/jbc.m115.657361] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Indexed: 01/09/2023] Open
Abstract
Insulin signaling augments glucose transport by regulating glucose transporter 4 (GLUT4) trafficking from specialized intracellular compartments, termed GLUT4 storage vesicles (GSVs), to the plasma membrane. Proteomic analysis of GSVs by mass spectrometry revealed enrichment of 59 proteins in these vesicles. We measured reduced abundance of 23 of these proteins following insulin stimulation and assigned these as high confidence GSV proteins. These included established GSV proteins such as GLUT4 and insulin-responsive aminopeptidase, as well as six proteins not previously reported to be localized to GSVs. Tumor suppressor candidate 5 (TUSC5) was shown to be a novel GSV protein that underwent a 3.7-fold increase in abundance at the plasma membrane in response to insulin. siRNA-mediated knockdown of TUSC5 decreased insulin-stimulated glucose uptake, although overexpression of TUSC5 had the opposite effect, implicating TUSC5 as a positive regulator of insulin-stimulated glucose transport in adipocytes. Incubation of adipocytes with TNFα caused insulin resistance and a concomitant reduction in TUSC5. Consistent with previous studies, peroxisome proliferator-activated receptor (PPAR) γ agonism reversed TNFα-induced insulin resistance. TUSC5 expression was necessary but insufficient for PPARγ-mediated reversal of insulin resistance. These findings functionally link TUSC5 to GLUT4 trafficking, insulin action, insulin resistance, and PPARγ action in the adipocyte. Further studies are required to establish the exact role of TUSC5 in adipocytes.
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Affiliation(s)
- Daniel J Fazakerley
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Sheyda Naghiloo
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Rima Chaudhuri
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Françoise Koumanov
- the Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, United Kingdom
| | - James G Burchfield
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Kristen C Thomas
- From the Charles Perkins Centre, School of Molecular Bioscience, and
| | - James R Krycer
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Matthew J Prior
- The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Ben L Parker
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Beverley A Murrow
- The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Jacqueline Stöckli
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Christopher C Meoli
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and
| | - Geoffrey D Holman
- the Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, United Kingdom
| | - David E James
- From the Charles Perkins Centre, School of Molecular Bioscience, and The Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia, and School of Medicine, University of Sydney, Sydney, New South Wales 2006, Australia,
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19
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Lizunov VA, Stenkula KG, Blank PS, Troy A, Lee JP, Skarulis MC, Cushman SW, Zimmerberg J. Human adipose cells in vitro are either refractory or responsive to insulin, reflecting host metabolic state. PLoS One 2015; 10:e0119291. [PMID: 25768970 PMCID: PMC4359092 DOI: 10.1371/journal.pone.0119291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 01/12/2015] [Indexed: 01/14/2023] Open
Abstract
While intercellular communication processes are frequently characterized by switch-like transitions, the endocrine system, including the adipose tissue response to insulin, has been characterized by graded responses. Yet here individual cells from adipose tissue biopsies are best described by a switch-like transition between the basal and insulin-stimulated states for the trafficking of the glucose transporter GLUT4. Two statistically-defined populations best describe the observed cellular heterogeneity, representing the fractions of refractive and responsive adipose cells. Furthermore, subjects exhibiting high systemic insulin sensitivity indices (SI) have high fractions of responsive adipose cells in vitro, while subjects exhibiting decreasing SI have increasing fractions of refractory cells in vitro. Thus, a two-component model best describes the relationship between cellular refractory fraction and subject SI. Since isolated cells exhibit these different response characteristics in the presence of constant culture conditions and milieu, we suggest that a physiological switching mechanism at the adipose cellular level ultimately drives systemic SI.
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Affiliation(s)
- Vladimir A. Lizunov
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
| | - Karin G. Stenkula
- Experimental Diabetes, Metabolism, and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States of America
- Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Paul S. Blank
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
| | - Aaron Troy
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
| | - Jo-Ping Lee
- Experimental Diabetes, Metabolism, and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States of America
| | - Monica C. Skarulis
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States of America
| | - Samuel W. Cushman
- Experimental Diabetes, Metabolism, and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States of America
| | - Joshua Zimmerberg
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
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20
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Tan SX, Fisher-Wellman KH, Fazakerley DJ, Ng Y, Pant H, Li J, Meoli CC, Coster ACF, Stöckli J, James DE. Selective insulin resistance in adipocytes. J Biol Chem 2015; 290:11337-48. [PMID: 25720492 DOI: 10.1074/jbc.m114.623686] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Indexed: 12/14/2022] Open
Abstract
Aside from glucose metabolism, insulin regulates a variety of pathways in peripheral tissues. Under insulin-resistant conditions, it is well known that insulin-stimulated glucose uptake is impaired, and many studies attribute this to a defect in Akt signaling. Here we make use of several insulin resistance models, including insulin-resistant 3T3-L1 adipocytes and fat explants prepared from high fat-fed C57BL/6J and ob/ob mice, to comprehensively distinguish defective from unaffected aspects of insulin signaling and its downstream consequences in adipocytes. Defective regulation of glucose uptake was observed in all models of insulin resistance, whereas other major actions of insulin such as protein synthesis and anti-lipolysis were normal. This defect corresponded to a reduction in the maximum response to insulin. The pattern of change observed for phosphorylation in the Akt pathway was inconsistent with a simple defect at the level of Akt. The only Akt substrate that showed consistently reduced phosphorylation was the RabGAP AS160 that regulates GLUT4 translocation. We conclude that insulin resistance in adipose tissue is highly selective for glucose metabolism and likely involves a defect in one of the components regulating GLUT4 translocation to the cell surface in response to insulin.
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Affiliation(s)
- Shi-Xiong Tan
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia
| | - Kelsey H Fisher-Wellman
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia
| | | | - Yvonne Ng
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia
| | - Himani Pant
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia
| | - Jia Li
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia
| | - Christopher C Meoli
- From the Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales 2010, Australia, the Charles Perkins Centre, School of Molecular Biosciences and
| | - Adelle C F Coster
- the School of Mathematics and Statistics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | | | - David E James
- the Charles Perkins Centre, School of Molecular Biosciences and the School of Medicine, University of Sydney, New South Wales 2006, Australia, and
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21
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Li J, Cantley J, Burchfield JG, Meoli CC, Stöckli J, Whitworth PT, Pant H, Chaudhuri R, Groffen AJA, Verhage M, James DE. DOC2 isoforms play dual roles in insulin secretion and insulin-stimulated glucose uptake. Diabetologia 2014; 57:2173-82. [PMID: 25005332 DOI: 10.1007/s00125-014-3312-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 05/28/2014] [Indexed: 01/08/2023]
Abstract
AIMS/HYPOTHESIS Glucose-stimulated insulin secretion (GSIS) and insulin-stimulated glucose uptake are processes that rely on regulated intracellular vesicle transport and vesicle fusion with the plasma membrane. DOC2A and DOC2B are calcium-sensitive proteins that were identified as key components of vesicle exocytosis in neurons. Our aim was to investigate the role of DOC2 isoforms in glucose homeostasis, insulin secretion and insulin action. METHODS DOC2 expression was measured by RT-PCR and western blotting. Body weight, glucose tolerance, insulin action and GSIS were assessed in wild-type (WT), Doc2a (-/-) (Doc2aKO), Doc2b (-/-) (Doc2bKO) and Doc2a (-/-)/Doc2b (-/-) (Doc2a/Doc2bKO) mice in vivo. In vitro GSIS and glucose uptake were assessed in isolated tissues, and exocytotic proteins measured by western blotting. GLUT4 translocation was assessed by epifluorescence microscopy. RESULTS Doc2b mRNA was detected in all tissues tested, whereas Doc2a was only detected in islets and the brain. Doc2aKO and Doc2bKO mice had minor glucose intolerance, while Doc2a/Doc2bKO mice showed pronounced glucose intolerance. GSIS was markedly impaired in Doc2a/Doc2bKO mice in vivo, and in isolated Doc2a/Doc2bKO islets in vitro. In contrast, Doc2bKO mice had only subtle defects in insulin secretion in vivo. Insulin action was impaired to a similar degree in both Doc2bKO and Doc2a/Doc2bKO mice. In vitro insulin-stimulated glucose transport and GLUT4 vesicle fusion were defective in adipocytes derived from Doc2bKO mice. Surprisingly, insulin action was not altered in muscle isolated from DOC2-null mice. CONCLUSIONS/INTERPRETATION Our study identifies a critical role for DOC2B in insulin-stimulated glucose uptake in adipocytes, and for the synergistic regulation of GSIS by DOC2A and DOC2B in beta cells.
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Affiliation(s)
- Jia Li
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
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22
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Haney SA. Rapid Assessment and Visualization of Normality in High-Content and Other Cell-Level Data and Its Impact on the Interpretation of Experimental Results. ACTA ACUST UNITED AC 2014; 19:672-84. [PMID: 24652972 DOI: 10.1177/1087057114526432] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 02/03/2014] [Indexed: 01/09/2023]
Abstract
When investigators monitor effects on a population of cells following a perturbation, these events rarely occur in a classical normal (or Gaussian) distribution. A normal distribution is, however, explicitly assumed for events within a single well, in which mean values per well are used as an assay metric and, in general, measures of assay robustness, such as the Z' score and the V factor. Such analysis is not possible for many technologies; however, high-content screening (HCS) measures events of individual cells, which are averaged over the well. These individual cell-level measurements may be analyzed separately. This study quantifies the extent of nonnormality in experimental samples and their effects on determining the EC50 of a test compound and the assay robustness statistics. The results, based on five sets of publicly available data, indicate that the Z' or V-factor score can be improved by as much as 0.44 more than standard calculations, and the EC50 of a dose-response curve can be lowered by as much as fivefold when nonparametric methods are used, but not all data sets show a significant improvement. The effect on analysis depends in part on whether the greatest shift from normality occurs in the upper or lower range of the dose-response curve.
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Affiliation(s)
- Steven A Haney
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, USA
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23
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Yang P, Patrick E, Tan SX, Fazakerley DJ, Burchfield J, Gribben C, Prior MJ, James DE, Hwa Yang Y. Direction pathway analysis of large-scale proteomics data reveals novel features of the insulin action pathway. ACTA ACUST UNITED AC 2013; 30:808-14. [PMID: 24167158 DOI: 10.1093/bioinformatics/btt616] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
MOTIVATION With the advancement of high-throughput techniques, large-scale profiling of biological systems with multiple experimental perturbations is becoming more prevalent. Pathway analysis incorporates prior biological knowledge to analyze genes/proteins in groups in a biological context. However, the hypotheses under investigation are often confined to a 1D space (i.e. up, down, either or mixed regulation). Here, we develop direction pathway analysis (DPA), which can be applied to test hypothesis in a high-dimensional space for identifying pathways that display distinct responses across multiple perturbations. RESULTS Our DPA approach allows for the identification of pathways that display distinct responses across multiple perturbations. To demonstrate the utility and effectiveness, we evaluated DPA under various simulated scenarios and applied it to study insulin action in adipocytes. A major action of insulin in adipocytes is to regulate the movement of proteins from the interior to the cell surface membrane. Quantitative mass spectrometry-based proteomics was used to study this process on a large-scale. The combined dataset comprises four separate treatments. By applying DPA, we identified that several insulin responsive pathways in the plasma membrane trafficking are only partially dependent on the insulin-regulated kinase Akt. We subsequently validated our findings through targeted analysis of key proteins from these pathways using immunoblotting and live cell microscopy. Our results demonstrate that DPA can be applied to dissect pathway networks testing diverse hypotheses and integrating multiple experimental perturbations. AVAILABILITY AND IMPLEMENTATION The R package 'directPA' is distributed from CRAN under GNU General Public License (GPL)-3 and can be downloaded from: http://cran.r-project.org/web/packages/directPA/index.html CONTACT jean.yang@sydney.edu.au SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Pengyi Yang
- Systems Biology Group, Biostatistics Branch, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, NC 27709, USA, School of Mathematics and Statistics, University of Sydney, Diabetes and Obesity Program, Garvan Institute of Medical Research, NSW 2006, Australia and Metabolism in Human Disease Unit, Institute of Molecular and Cellular Biology, A*Star, 61 Biopolis Drive, Proteos 138673, Singapore
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