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Martins VF, LaBarge SA, Stanley A, Svensson K, Hung CW, Keinan O, Ciaraldi TP, Banoian D, Park JE, Ha C, Hetrick B, Meyer GA, Philp A, David LL, Henry RR, Aslan JE, Saltiel AR, McCurdy CE, Schenk S. p300 or CBP is required for insulin-stimulated glucose uptake in skeletal muscle and adipocytes. JCI Insight 2021; 7:141344. [PMID: 34813504 PMCID: PMC8765050 DOI: 10.1172/jci.insight.141344] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 11/19/2021] [Indexed: 11/17/2022] Open
Abstract
While current thinking posits that insulin signaling to GLUT4 exocytic translocation and glucose uptake in skeletal muscle and adipocytes is controlled by phosphorylation-based signaling, many proteins in this pathway are acetylated on lysine residues. However, the importance of acetylation and lysine acetyltransferases to insulin-stimulated glucose uptake is incompletely defined. Here, we demonstrate that combined loss of the acetyltransferases E1A binding protein p300 (p300) and cAMP response element binding protein binding protein (CBP) in mouse skeletal muscle causes a complete loss of insulin-stimulated glucose uptake. Similarly, brief (i.e. 1 h) pharmacological inhibition of p300/CBP acetyltransferase activity recapitulates this phenotype in human and rodent myotubes, 3T3-L1 adipocytes, and mouse muscle. Mechanistically, these effects are due to p300/CBP-mediated regulation of GLUT4 exocytic translocation and occurs downstream of Akt signaling. Taken together, we highlight a fundamental role for acetylation and p300/CBP in the direct regulation of insulin-stimulated glucose transport in skeletal muscle and adipocytes.
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Affiliation(s)
- Vitor F Martins
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Samuel A LaBarge
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Alexandra Stanley
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Kristoffer Svensson
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Chao-Wei Hung
- Department of Medicine, University of California, San Diego, La Jolla, United States of America
| | - Omer Keinan
- Department of Medicine, University of California, San Diego, La Jolla, United States of America
| | - Theodore P Ciaraldi
- Department of Medicine, University of California, San Diego, La Jolla, United States of America
| | - Dion Banoian
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Ji E Park
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Christina Ha
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
| | - Byron Hetrick
- Department of Human Physiology, University of Oregon, Eugene, United States of America
| | - Gretchen A Meyer
- Program in Physical Therapy, Washington University in St. Louis, St. Louis, United States of America
| | - Andrew Philp
- Mitochondrial Metabolism and Ageing, Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Larry L David
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, United States of America
| | - Robert R Henry
- Division of Endocrinology & Metabolism, VA San Diego Healthcare System, San Diego, United States of America
| | - Joseph E Aslan
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, United States of America
| | - Alan R Saltiel
- University of California, San Diego, La Jolla, United States of America
| | - Carrie E McCurdy
- Department of Human Physiology, University of Oregon, Eugene, United States of America
| | - Simon Schenk
- Department of Orthopedic Surgery, University of California, San Diego, La Jolla, United States of America
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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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Komakula SB, Tiwari AK, Singh S. A novel quantitative assay for analysis of GLUT4 translocation using high content screening. Biomed Pharmacother 2021; 133:111032. [PMID: 33378945 DOI: 10.1016/j.biopha.2020.111032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/11/2020] [Accepted: 11/15/2020] [Indexed: 12/23/2022] Open
Abstract
Insulin resistance is associated with obesity and can lead to several metabolic disorders including type II diabetes, nonalcoholic fatty liver disease and cardiovascular problems. Search for the small molecules which can either induce or mimic the insulin action are of great interest and can be utilized to manage insulin resistance. There are several dietary phytochemicals which can potentially have insulinomimetic action. Nevertheless, high throughput screening methods to test efficiency of small molecules to act as an insulinomimetic are not fully established. In this paper we have performed chemical screen analysis based on GLUT4 translocation using a cell line CHO-HIRC-myc-GLUT4 eGFP that expresses GLUT4-GFP in association with human Insulin receptor. We have established a high content screening-based method which can track and quantify the GLUT4 translocation from perinuclear area to the cell membrane. The assay involves measuring fluorescence intensity in a defined perinuclear area and a defined area along the cell membrane; and the results are expressed as the ratio of fluorescence intensity in the perinuclear to membrane area. The assay could collect real time data of GLUT4 translocation from thousand of cells/ sample and from many such samples in one experiment. We validated the assay using Insulin, insulin mimics/sensitizers and insulin inhibitors. The agonist or antagonists were analyzed for their ability to enhance or block the GLUT4 translocation independent of insulin. The outcome of the assay was correlated by performing glucose uptake assay using differentiated 3T3L1 cells. Using this platform we further identified several plant extracts which had the insulin mimetic action. We confirmed that these plant extracts were non-toxic to the beta cells using RIN mf5cells and 3T3L1 cells. We have identified plant extracts with the potential insulinomimetic action using novel high-content screening approach; these can be further tested for their efficiency in-vivo in pre-clinical trials.
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Affiliation(s)
- SaiSantosh Babu Komakula
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India; Department of Experimental Biology, Wrocław University of Environmental and Life Sciences, Wroclaw, Poland
| | | | - Shashi Singh
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.
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Jaldin-Fincati JR, Pavarotti M, Frendo-Cumbo S, Bilan PJ, Klip A. Update on GLUT4 Vesicle Traffic: A Cornerstone of Insulin Action. Trends Endocrinol Metab 2017; 28:597-611. [PMID: 28602209 DOI: 10.1016/j.tem.2017.05.002] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/08/2017] [Accepted: 05/09/2017] [Indexed: 12/20/2022]
Abstract
Glucose transport is rate limiting for dietary glucose utilization by muscle and fat. The glucose transporter GLUT4 is dynamically sorted and retained intracellularly and redistributes to the plasma membrane (PM) by insulin-regulated vesicular traffic, or 'GLUT4 translocation'. Here we emphasize recent findings in GLUT4 translocation research. The application of total internal reflection fluorescence microscopy (TIRFM) has increased our understanding of insulin-regulated events beneath the PM, such as vesicle tethering and membrane fusion. We describe recent findings on Akt-targeted Rab GTPase-activating proteins (GAPs) (TBC1D1, TBC1D4, TBC1D13) and downstream Rab GTPases (Rab8a, Rab10, Rab13, Rab14, and their effectors) along with the input of Rac1 and actin filaments, molecular motors [myosinVa (MyoVa), myosin1c (Myo1c), myosinIIA (MyoIIA)], and membrane fusion regulators (syntaxin4, munc18c, Doc2b). Collectively these findings reveal novel events in insulin-regulated GLUT4 traffic.
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Affiliation(s)
| | - Martin Pavarotti
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza 5500, Argentina
| | - Scott Frendo-Cumbo
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Philip J Bilan
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada
| | - Amira Klip
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
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Kruse R, Krantz J, Barker N, Coletta RL, Rafikov R, Luo M, Højlund K, Mandarino LJ, Langlais PR. Characterization of the CLASP2 Protein Interaction Network Identifies SOGA1 as a Microtubule-Associated Protein. Mol Cell Proteomics 2017; 16:1718-1735. [PMID: 28550165 DOI: 10.1074/mcp.ra117.000011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Indexed: 12/26/2022] Open
Abstract
CLASP2 is a microtubule-associated protein that undergoes insulin-stimulated phosphorylation and co-localization with reorganized actin and GLUT4 at the plasma membrane. To gain insight to the role of CLASP2 in this system, we developed and successfully executed a streamlined interactome approach and built a CLASP2 protein network in 3T3-L1 adipocytes. Using two different commercially available antibodies for CLASP2 and an antibody for epitope-tagged, overexpressed CLASP2, we performed multiple affinity purification coupled with mass spectrometry (AP-MS) experiments in combination with label-free quantitative proteomics and analyzed the data with the bioinformatics tool Significance Analysis of Interactome (SAINT). We discovered that CLASP2 coimmunoprecipitates (co-IPs) the novel protein SOGA1, the microtubule-associated protein kinase MARK2, and the microtubule/actin-regulating protein G2L1. The GTPase-activating proteins AGAP1 and AGAP3 were also enriched in the CLASP2 interactome, although subsequent AGAP3 and CLIP2 interactome analysis suggests a preference of AGAP3 for CLIP2. Follow-up MARK2 interactome analysis confirmed reciprocal co-IP of CLASP2 and revealed MARK2 can co-IP SOGA1, glycogen synthase, and glycogenin. Investigating the SOGA1 interactome confirmed SOGA1 can reciprocal co-IP both CLASP2 and MARK2 as well as glycogen synthase and glycogenin. SOGA1 was confirmed to colocalize with CLASP2 and with tubulin, which identifies SOGA1 as a new microtubule-associated protein. These results introduce the metabolic function of these proposed novel protein networks and their relationship with microtubules as new fields of cytoskeleton-associated protein biology.
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Affiliation(s)
- Rikke Kruse
- From the ‡The Section of Molecular Diabetes & Metabolism, Department of Clinical Research and Institute of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark.,§Department of Endocrinology, Odense University Hospital, DK-5000 Odense, Denmark
| | - James Krantz
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Natalie Barker
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Richard L Coletta
- ‖School of Life Sciences, Arizona State University, Tempe, Arizona 85787
| | - Ruslan Rafikov
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Moulun Luo
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Kurt Højlund
- From the ‡The Section of Molecular Diabetes & Metabolism, Department of Clinical Research and Institute of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark.,§Department of Endocrinology, Odense University Hospital, DK-5000 Odense, Denmark
| | - Lawrence J Mandarino
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Paul R Langlais
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721;
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Silva Frederico MJ, Mascarello A, Castro AJG, Da Luz G, Altenhofen D, Mendes CP, Leal PC, Yunes RA, Nunes RJ, Silva FRMB. Incretinomimetic and Insulinomimetic Effect of (2E)-N′-(1′-Naphthyl)-3,4,5-Trimethoxybenzohydrazide for Glycemic Homeostasis. J Cell Biochem 2015; 117:1199-209. [DOI: 10.1002/jcb.25403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/06/2015] [Indexed: 12/29/2022]
Affiliation(s)
- Marisa Jádna Silva Frederico
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
| | - Alessandra Mascarello
- Departamento de Química; Universidade Federal de Santa Catarina; Centro de Ciências Físicas e Matemáticas; Campus Universitário; Bairro Trindade; CEP: 88040-900 Florianópolis SC Brazil
| | - Allisson Jhonatan Gomes Castro
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
| | - Gabrielle Da Luz
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
| | - Delsi Altenhofen
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
| | - Camila Pires Mendes
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
| | - Paulo Cesar Leal
- Departamento de Química; Universidade Federal de Santa Catarina; Centro de Ciências Físicas e Matemáticas; Campus Universitário; Bairro Trindade; CEP: 88040-900 Florianópolis SC Brazil
| | - Rosendo Augusto Yunes
- Departamento de Química; Universidade Federal de Santa Catarina; Centro de Ciências Físicas e Matemáticas; Campus Universitário; Bairro Trindade; CEP: 88040-900 Florianópolis SC Brazil
| | - Ricardo José Nunes
- Departamento de Química; Universidade Federal de Santa Catarina; Centro de Ciências Físicas e Matemáticas; Campus Universitário; Bairro Trindade; CEP: 88040-900 Florianópolis SC Brazil
| | - Fátima Regina Mena Barreto Silva
- Departamento de Bioquímica; Universidade Federal de Santa Catarina; Centro de Ciências Biológicas; Campus Universitário; Bairro Trindade; Cx. Postal 5069, CEP: 88040-970 Florianópolis SC Brazil
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Castro AJG, Frederico MJS, Cazarolli LH, Mendes CP, Bretanha LC, Schmidt ÉC, Bouzon ZL, de Medeiros Pinto VA, da Fonte Ramos C, Pizzolatti MG, Silva FRMB. The mechanism of action of ursolic acid as insulin secretagogue and insulinomimetic is mediated by cross-talk between calcium and kinases to regulate glucose balance. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1850:51-61. [PMID: 25312987 DOI: 10.1016/j.bbagen.2014.10.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 09/23/2014] [Accepted: 10/03/2014] [Indexed: 12/29/2022]
Abstract
BACKGROUND The effect of in vivo treatment with ursolic acid (UA) on glycemia in hyperglycemic rats and its mechanism of action on muscle were studied. METHODS The UA effects on glycemia, glycogen, LDH, calcium and on insulin levels were evaluated after glucose tolerance curve. The β-cells were evaluated through the transmission electron microscopy. UA mechanism of action was studied on muscles through the glucose uptake with/without specific insulin signaling inhibitors. The nuclear effect of UA and the GLUT4 expression on muscle were studied using thymidine, GLUT4 immunocontent, immunofluorescence and RT-PCR. RESULTS UA presented a potent antihyperglycemic effect, increased insulin vesicle translocation, insulin secretion and augmented glycogen content. Also, UA stimulates the glucose uptake through the involvement of the classical insulin signaling related to the GLUT4 translocation to the plasma membrane as well as the GLUT4 synthesis. These were characterized by increasing the GLUT4 mRNA expression, the activation of DNA transcription, the expression of GLUT4 and its presence at plasma membrane. Also, the modulation of calcium, phospholipase C, protein kinase C and PKCaM II is mandatory for the full stimulatory effect of UA on glucose uptake. UA did not change the serum LDH and serum calcium balance. CONCLUSIONS The antihyperglycemic role of UA is mediated through insulin secretion and insulinomimetic effect on glucose uptake, synthesis and translocation of GLUT4 by a mechanism of cross-talk between calcium and protein kinases. GENERAL SIGNIFICANCE UA is a potential anti-diabetic agent with pharmacological properties for insulin resistance and diabetes therapy.
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Affiliation(s)
- Allisson Jhonatan Gomes Castro
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Marisa Jádna Silva Frederico
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Luisa Helena Cazarolli
- Universidade Federal da Fronteira Sul, Campus Universitário Laranjeiras do Sul, Laranjeiras do Sul, PR, Brazil
| | - Camila Pires Mendes
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Lizandra Czermainski Bretanha
- Departamento de Química, Centro de Ciências Físicas e Matemáticas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Éder Carlos Schmidt
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Zenilda Laurita Bouzon
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | | | | | - Moacir Geraldo Pizzolatti
- Departamento de Química, Centro de Ciências Físicas e Matemáticas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
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Chen Y, Lippincott-Schwartz J. Insulin triggers surface-directed trafficking of sequestered GLUT4 storage vesicles marked by Rab10. Small GTPases 2013; 4:193-7. [PMID: 24030635 PMCID: PMC3976978 DOI: 10.4161/sgtp.26471] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Understanding how glucose transporter isoform 4 (GLUT4) redistributes to the plasma membrane during insulin stimulation is a major goal of glucose transporter research. GLUT4 molecules normally reside in numerous intracellular compartments, including specialized storage vesicles and early/recycling endosomes. It is unclear how these diverse compartments respond to insulin stimulation to deliver GLUT4 molecules to the plasma membrane. For example, do they fuse with each other first or remain as separate compartments with different trafficking characteristics? Our recent live cell imaging studies are helping to clarify these issues. Using Rab proteins as specific markers to distinguish between storage vesicles and endosomes containing GLUT4, we demonstrate that it is primarily internal GLUT4 storage vesicles (GSVs) marked by Rab10 that approach and fuse at the plasma membrane and GSVs don’t interact with endosomes on their way to the plasma membrane. These new findings add strong support to the model that GSV release from intracellular retention plays a major role in supplying GLUT4 molecules onto the PM under insulin stimulation.
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Affiliation(s)
- Yu Chen
- The Eugene Kennedy Shriver National Institute of Child Health and Human Development; National Institutes of Health; Bethesda, MD USA
| | - Jennifer Lippincott-Schwartz
- The Eugene Kennedy Shriver National Institute of Child Health and Human Development; National Institutes of Health; Bethesda, MD USA
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9
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Cazarolli LH, Pereira DF, Kappel VD, Folador P, Figueiredo MDSRB, Pizzolatti MG, Silva FRMB. Insulin signaling: A potential signaling pathway for the stimulatory effect of kaempferitrin on glucose uptake in skeletal muscle. Eur J Pharmacol 2013; 712:1-7. [DOI: 10.1016/j.ejphar.2013.02.029] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 02/08/2013] [Accepted: 02/14/2013] [Indexed: 11/27/2022]
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Raith M, Valencia RG, Fischer I, Orthofer M, Penninger JM, Spuler S, Rezniczek GA, Wiche G. Linking cytoarchitecture to metabolism: sarcolemma-associated plectin affects glucose uptake by destabilizing microtubule networks in mdx myofibers. Skelet Muscle 2013; 3:14. [PMID: 23758845 PMCID: PMC3695810 DOI: 10.1186/2044-5040-3-14] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/11/2013] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Duchenne muscular dystrophy (DMD) is one of the most frequent forms of muscular disorders. It is caused by the absence of dystrophin, a core component of the sarcolemma-associated junctional complex that links the cytoskeleton to the extracellular matrix. We showed previously that plectin 1f (P1f), one of the major muscle-expressed isoforms of the cytoskeletal linker protein plectin, accumulates at the sarcolemma of DMD patients as well as of mdx mice, a widely studied animal model for DMD.Based on plectin's dual role as structural protein and scaffolding platform for signaling molecules, we speculated that the dystrophic phenotype observed after loss of dystrophin was caused, at least to some extent, by excess plectin. Thus, we hypothesized that elimination of plectin expression in mdx skeletal muscle, while probably resulting in an overall more severe phenotype, may lead to a partial phenotype rescue. In particular, we wanted to assess whether excess sarcolemmal plectin contributes to the dysregulation of sugar metabolism in mdx myofibers. METHODS We generated plectin/dystrophin double deficient (dKO) mice by breeding mdx with conditional striated muscle-restricted plectin knockout (cKO) mice. The phenotype of these mice was comparatively analyzed with that of mdx, cKO, and wild-type mice, focusing on structural integrity and dysregulation of glucose metabolism. RESULTS We show that the accumulation of plectin at the sarcolemma of mdx muscle fibers hardly compensated for their loss of structural integrity. Instead, it led to an additional metabolic deficit by impairing glucose uptake. While dKO mice suffered from an overall more severe form of muscular dystrophy compared to mdx or plectin-deficient mice, sarcolemmal integrity as well as glucose uptake of their myofibers were restored to normal levels upon ablation of plectin. Furthermore, microtubule (MT) networks in intact dKO myofibers, including subsarcolemmal areas, were found to be more robust than those in mdx mice. Finally, myotubes differentiated from P1f-overexpressing myoblasts showed an impairment of glucose transporter 4 translocation and a destabilization of MT networks. CONCLUSIONS Based on these results we propose that sarcolemma-associated plectin acts as an antagonist of MT network formation in myofibers, thereby hindering vesicle-mediated (MT-dependent) transport of glucose transporter 4. This novel role of plectin throws a bridge between extra-sarcomeric cytoarchitecture and metabolism of muscle fibers. Our study thus provides new insights into pathomechanisms of plectinopathies and muscular dystrophies in general.
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Affiliation(s)
- Marianne Raith
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, Vienna, 1030, Austria
| | - Rocio G Valencia
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, Vienna, 1030, Austria
| | - Irmgard Fischer
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, Vienna, 1030, Austria
| | - Michael Orthofer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr.-Bohr-Gasse 3, Vienna, 1030, Austria
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr.-Bohr-Gasse 3, Vienna, 1030, Austria
| | - Simone Spuler
- Muscle Research Unit, Experimental and Clinical Research Center, Lindenberger Weg 80, Berlin, 13125, Germany
| | - Günther A Rezniczek
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, Vienna, 1030, Austria
- Department of Obstetrics and Gynecology (Marienhospital Herne), Ruhr-Universität Bochum, Düngelstrasse 33, Herne, 44623, Germany
| | - Gerhard Wiche
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, Vienna, 1030, Austria
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Liu LZ, Cheung SCK, Lan LL, Ho SKS, Chan JCN, Tong PCY. Microtubule network is required for insulin-induced signal transduction and actin remodeling. Mol Cell Endocrinol 2013; 365:64-74. [PMID: 22996137 DOI: 10.1016/j.mce.2012.09.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 08/14/2012] [Accepted: 09/08/2012] [Indexed: 02/02/2023]
Abstract
Both microtubule and actin are required for insulin-induced glucose uptake. However, the roles of these two cytoskeletons and their relationship in insulin action still remain unclear. In this work, we examined the morphological change of microtubule/actin and their involvement in insulin signal transduction using rat skeletal muscle cells. Insulin rapidly led to microtubule clustering from ventral to dorsal surface of the cell. Microtubule filaments were rearranged to create space where new actin structures formed. Disruption of microtubule prevented insulin-induced actin remodeling and distal insulin signal transduction, with reduction in surface glucose transporter isoform 4 (GLUT4) and glucose uptake. Though microtubule mediated actin remodeling through PKCζ, reorganization of microtubule depended on tyrosine phosphorylation of insulin receptor, the mechanism is different from insulin-induced actin remodeling, which relied on the activity of PI3-kinase and PKCζ. We propose that microtubule network is required for insulin-induced signal transduction and actin remodeling in skeletal muscle cells.
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Affiliation(s)
- Li-Zhong Liu
- Department of Medicine and Therapeutics, Hong Kong Institute of Diabetes and Obesity, Li Ka Shing Institute of Health, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
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Chen Y, Wang Y, Zhang J, Deng Y, Jiang L, Song E, Wu XS, Hammer JA, Xu T, Lippincott-Schwartz J. Rab10 and myosin-Va mediate insulin-stimulated GLUT4 storage vesicle translocation in adipocytes. ACTA ACUST UNITED AC 2012; 198:545-60. [PMID: 22908308 PMCID: PMC3514028 DOI: 10.1083/jcb.201111091] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rab proteins are important regulators of insulin-stimulated GLUT4 translocation to the plasma membrane (PM), but the precise steps in GLUT4 trafficking modulated by particular Rab proteins remain unclear. Here, we systematically investigate the involvement of Rab proteins in GLUT4 trafficking, focusing on Rab proteins directly mediating GLUT4 storage vesicle (GSV) delivery to the PM. Using dual-color total internal reflection fluorescence (TIRF) microscopy and an insulin-responsive aminopeptidase (IRAP)-pHluorin fusion assay, we demonstrated that Rab10 directly facilitated GSV translocation to and docking at the PM. Rab14 mediated GLUT4 delivery to the PM via endosomal compartments containing transferrin receptor (TfR), whereas Rab4A, Rab4B, and Rab8A recycled GLUT4 through the endosomal system. Myosin-Va associated with GSVs by interacting with Rab10, positioning peripherally recruited GSVs for ultimate fusion. Thus, multiple Rab proteins regulate the trafficking of GLUT4, with Rab10 coordinating with myosin-Va to mediate the final steps of insulin-stimulated GSV translocation to the PM.
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Affiliation(s)
- Yu Chen
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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13
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Langlais P, Dillon JL, Mengos A, Baluch DP, Ardebili R, Miranda DN, Xie X, Heckmann BL, Liu J, Mandarino LJ. Identification of a role for CLASP2 in insulin action. J Biol Chem 2012; 287:39245-53. [PMID: 22992739 DOI: 10.1074/jbc.m112.394148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Insulin stimulates the mobilization of glucose transporter 4 (GLUT4) storage vesicles to the plasma membrane, resulting in an influx of glucose into target tissues such as muscle and fat. We present evidence that CLIP-associating protein 2 (CLASP2), a protein previously unassociated with insulin action, is responsive to insulin stimulation. Using mass spectrometry-based protein identification combined with phosphoantibody immunoprecipitation in L6 myotubes, we detected a 4.8-fold increase of CLASP2 in the anti-phosphoserine immunoprecipitates upon insulin stimulation. Western blotting of CLASP2 immunoprecipitates with the phosphoantibody confirmed the finding that CLASP2 undergoes insulin-stimulated phosphorylation, and a number of novel phosphorylation sites were identified. Confocal imaging of L6 myotubes revealed that CLASP2 colocalizes with GLUT4 at the plasma membrane within areas of insulin-mediated cortical actin remodeling. CLASP2 is responsible for directing the distal end of microtubules to the cell cortex, and it has been shown that GLUT4 travels along microtubule tracks. In support of the concept that CLASP2 plays a role in the trafficking of GLUT4 at the cell periphery, CLASP2 knockdown by siRNA in L6 myotubes interfered with insulin-stimulated GLUT4 localization to the plasma membrane. Furthermore, siRNA mediated knockdown of CLASP2 in 3T3-L1 adipocytes inhibited insulin-stimulated glucose transport. We therefore propose a new model for CLASP2 in insulin action, where CLASP2 directs the delivery of GLUT4 to cell cortex landing zones important for insulin action.
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Affiliation(s)
- Paul Langlais
- Center for Metabolic and Vascular Biology, Arizona State University, Tempe, Arizona 85287, USA
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14
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Sites of glucose transporter-4 vesicle fusion with the plasma membrane correlate spatially with microtubules. PLoS One 2012; 7:e43662. [PMID: 22916292 PMCID: PMC3423385 DOI: 10.1371/journal.pone.0043662] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 07/23/2012] [Indexed: 12/25/2022] Open
Abstract
In adipocytes, vesicles containing glucose transporter-4 (GLUT4) redistribute from intracellular stores to the cell periphery in response to insulin stimulation. Vesicles then fuse with the plasma membrane, facilitating glucose transport into the cell. To gain insight into the details of microtubule involvement, we examined the spatial organization and dynamics of microtubules in relation to GLUT4 vesicle trafficking in living 3T3-L1 adipocytes using total internal reflection fluorescence (TIRF) microscopy. Insulin stimulated an increase in microtubule density and curvature within the TIRF-illuminated region of the cell. The high degree of curvature and abrupt displacements of microtubules indicate that substantial forces act on microtubules. The time course of the microtubule density increase precedes that of the increase in intensity of fluorescently-tagged GLUT4 in this same region of the cell. In addition, portions of the microtubules are highly curved and are pulled closer to the cell cortex, as confirmed by Parallax microscopy. Microtubule disruption delayed and modestly reduced GLUT4 accumulation at the plasma membrane. Quantitative analysis revealed that fusions of GLUT4-containing vesicles with the plasma membrane, detected using insulin-regulated aminopeptidase with a pH-sensitive GFP tag (pHluorin), preferentially occur near microtubules. Interestingly, long-distance vesicle movement along microtubules visible at the cell surface prior to fusion does not appear to account for this proximity. We conclude that microtubules may be important in providing spatial information for GLUT4 vesicle fusion.
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Abstract
Despite daily fasting and feeding, plasma glucose levels are normally maintained within a narrow range owing to the hormones insulin and glucagon. Insulin increases glucose uptake into fat and muscle cells through the regulated trafficking of vesicles that contain glucose transporter type 4 (GLUT4). New insights into insulin signalling reveal that phosphorylation events initiated by the insulin receptor regulate key GLUT4 trafficking proteins, including small GTPases, tethering complexes and the vesicle fusion machinery. These proteins, in turn, control GLUT4 movement through the endosomal system, formation and retention of specialized GLUT4 storage vesicles and targeted exocytosis of these vesicles. Understanding these processes may help to explain the development of insulin resistance in type 2 diabetes and provide new potential therapeutic targets.
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16
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van Schothorst EM, Bunschoten A, Verlinde E, Schrauwen P, Keijer J. Glycemic index differences of high-fat diets modulate primarily lipid metabolism in murine adipose tissue. Physiol Genomics 2011; 43:942-9. [DOI: 10.1152/physiolgenomics.00042.2011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A low vs. high glycemic index of a high-fat (HF) diet (LGI and HGI, respectively) significantly retarded adverse health effects in adult male C57BL/6J mice, as shown recently (Van Schothorst EM, Bunschoten A, Schrauwen P, Mensink RP, Keijer J. FASEB J 23: 1092–1101, 2009). The LGI diet enhanced whole body insulin sensitivity and repressed HF diet-induced body and white adipose tissue (WAT) weight gain, resulting in significantly reduced serum leptin and resistin levels and increased adiponectin levels. We questioned how WAT is modulated and characterized the molecular mechanisms underlying the glycemic index-mediated effects using whole genome microarrays. This showed that the LGI diet mainly exerts its beneficial effects via substrate metabolism, especially fatty acid metabolism. In addition, cell adhesion and cytoskeleton remodeling showed reduced expression, in line with lower WAT mass. An important transcription factor showing enhanced expression is PPAR-γ. Furthermore, serum levels of triglycerides, total cholesterol, and HDL- and LDL-cholesterol were all significantly reduced by LGI diet, and simultaneously muscle insulin sensitivity was significantly increased as analyzed by protein kinase B/Akt phosphorylation. Cumulatively, even though these mice were fed an HF diet, the LGI diet induced significantly favorable changes in metabolism in WAT. These effects suggest a partial overlap with pharmacological approaches by thiazolidinediones to treat insulin resistance and statins for hypercholesterolemia. It is therefore tempting to speculate that such a dietary approach might beneficially support pharmacological treatment of insulin resistance or hypercholesterolemia in humans.
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Affiliation(s)
- Evert M. van Schothorst
- Top Institute Food and Nutrition
- Human and Animal Physiology, Wageningen University, Wageningen; and
| | - Annelies Bunschoten
- Top Institute Food and Nutrition
- Human and Animal Physiology, Wageningen University, Wageningen; and
| | - Eline Verlinde
- Human and Animal Physiology, Wageningen University, Wageningen; and
| | - Patrick Schrauwen
- Top Institute Food and Nutrition
- Department of Human Biology, Maastricht University, Maastricht, The Netherlands
| | - Jaap Keijer
- Top Institute Food and Nutrition
- Human and Animal Physiology, Wageningen University, Wageningen; and
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Liu D, Meckel T, Long EO. Distinct role of rab27a in granule movement at the plasma membrane and in the cytosol of NK cells. PLoS One 2010; 5:e12870. [PMID: 20877725 PMCID: PMC2943471 DOI: 10.1371/journal.pone.0012870] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 08/27/2010] [Indexed: 02/05/2023] Open
Abstract
Protocols were developed to automate image analysis and to track the movement of thousands of vesicular compartments in live cells. Algorithms were used to discriminate among different types of movement (e.g. random, caged, and directed). We applied these tools to investigate the steady-state distribution and movement of lytic granules (LG) in live natural killer (NK) cells by high-speed 3-dimensional (3D) spinning disc confocal and 2-dimensional total internal reflection fluorescence microscopy. Both mouse NK cells and a human NK cell line deficient in the small GTPase Rab27a were examined. The unbiased analysis of large datasets led to the following observations and conclusions. The majority of LG in the cytosol and at the plasma membrane of unstimulated NK cells are mobile. The use of inhibitors indicated that movement in the cytosol required microtubules but not actin, whereas movement at the plasma membrane required both. Rab27a deficiency resulted in fewer LG, and in a reduced fraction of mobile LG, at the plasma membrane. In contrast, loss of Rab27a increased the fraction of mobile LG and the extent of their movement in the cytosol. Therefore, in addition to its documented role in LG delivery to the plasma membrane, Rab27a may restrict LG movement in the cytosol.
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Affiliation(s)
- Dongfang Liu
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Tobias Meckel
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Eric O. Long
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail:
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Burchfield JG, Lopez JA, Mele K, Vallotton P, Hughes WE. Exocytotic vesicle behaviour assessed by total internal reflection fluorescence microscopy. Traffic 2010; 11:429-39. [PMID: 20070611 DOI: 10.1111/j.1600-0854.2010.01039.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The regulated trafficking or exocytosis of cargo-containing vesicles to the cell surface is fundamental to all cells. By coupling the technology of fluorescently tagged fusion proteins with total internal reflection fluorescence microscopy (TIRFM), it is possible to achieve the high spatio-temporal resolution required to study the dynamics of sub-plasma membrane vesicle trafficking and exocytosis. TIRFM has been used in a number of cell types to visualize and dissect the various steps of exocytosis revealing how molecules identified via genetic and/or biochemical approaches are involved in the regulation of this process. Here, we summarize the contribution of TIRFM to our understanding of the mechanism of exocytosis and discuss the novel methods of analysis that are required to exploit the large volumes of data that can be produced using this technique.
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Affiliation(s)
- James G Burchfield
- The Garvan Institute of Medical Research, 384 Victoria Street, Sydney, New South Wales 2010, Australia
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Abstract
Insulin stimulates GLUT4 (glucose transporter 4) translocation in adipocytes and muscles. An emerging picture is that Rab10 could bridge the gap between the insulin signalling cascade and GLUT4 translocation in adipocytes. In the present study, two potential effectors of Rab10, GDI (guanine-nucleotide-dissociation inhibitor)-1 and GDI-2, are characterized in respect to their roles in insulin-stimulated GLUT4 translocation. It is shown that both GDI-1 and GDI-2 exhibit similar distribution to GLUT4 and Rab10 at the TGN (trans-Golgi network) and periphery structures. Meanwhile, GDI-1 clearly interacts with Rab10 with higher affinity, as shown by both immunoprecipitation and in vivo FRET (fluorescence resonance energy transfer). In addition, the participation of GDIs in GLUT4 translocation is illustrated when overexpression of either GDI inhibits insulin-stimulated GLUT4 translocation in 3T3-L1 adipocytes. Taken together, we propose that GDI-1 is preferentially involved in insulin-stimulated GLUT4 translocation through facilitating Rab10 recycling.
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Lopez JA, Burchfield JG, Blair DH, Mele K, Ng Y, Vallotton P, James DE, Hughes WE. Identification of a distal GLUT4 trafficking event controlled by actin polymerization. Mol Biol Cell 2009; 20:3918-29. [PMID: 19605560 DOI: 10.1091/mbc.e09-03-0187] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The insulin-stimulated trafficking of GLUT4 to the plasma membrane in muscle and fat tissue constitutes a central process in blood glucose homeostasis. The tethering, docking, and fusion of GLUT4 vesicles with the plasma membrane (PM) represent the most distal steps in this pathway and have been recently shown to be key targets of insulin action. However, it remains unclear how insulin influences these processes to promote the insertion of the glucose transporter into the PM. In this study we have identified a previously uncharacterized role for cortical actin in the distal trafficking of GLUT4. Using high-frequency total internal reflection fluorescence microscopy (TIRFM) imaging, we show that insulin increases actin polymerization near the PM and that disruption of this process inhibited GLUT4 exocytosis. Using TIRFM in combination with probes that could distinguish between vesicle transport and fusion, we found that defective actin remodeling was accompanied by normal insulin-regulated accumulation of GLUT4 vesicles close to the PM, but the final exocytotic fusion step was impaired. These data clearly resolve multiple steps of the final stages of GLUT4 trafficking, demonstrating a crucial role for actin in the final stage of this process.
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Affiliation(s)
- Jamie A Lopez
- Diabetes and Obesity Research Program, The Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
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21
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RUVBL2, a novel AS160-binding protein, regulates insulin-stimulated GLUT4 translocation. Cell Res 2009; 19:1090-7. [DOI: 10.1038/cr.2009.68] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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22
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Cazarolli LH, Folador P, Moresco HH, Brighente IMC, Pizzolatti MG, Silva FRMB. Mechanism of action of the stimulatory effect of apigenin-6-C-(2''-O-alpha-l-rhamnopyranosyl)-beta-L-fucopyranoside on 14C-glucose uptake. Chem Biol Interact 2008; 179:407-12. [PMID: 19070612 DOI: 10.1016/j.cbi.2008.11.012] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 11/13/2008] [Accepted: 11/14/2008] [Indexed: 11/17/2022]
Abstract
There has been a growing interest in hypoglycemic agents from natural products, particularly those derived from plants. Flavonoids are naturally occurring phenolic compounds with a broad range of biological activities and the beneficial effects of flavonoids have been studied in relation to diabetes mellitus, either through their capacity to avoid glucose absorption or to improve glucose tolerance. The purpose of this study was to investigate the mechanism of action of the stimulatory effect of apigenin-6-C-(2''-O-alpha-L-rhamnopyranosyl)-beta-L-fucopyranoside (1), isolated from Averrhoa carambola L. (Oxalidaceae) leaves, on (14)C-glucose uptake. This compound (1) was found to have an acute effect on blood glucose lowering in diabetic rats and stimulated glucose-induced insulin secretion after oral treatment in hyperglycemic rats. A significant stimulatory effect of compound 1 on (14)C-glucose uptake was observed at 50 and 100 microM. The effect of compound 1 on glucose uptake was completely nullified by wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K), RO318220, an inhibitor of protein kinase C (PKC), PD98059, a specific inhibitor of mitogen-activated protein kinase (MEK), cycloheximide, an inhibitor of protein synthesis, and colchicine, a microtubule-depolymerizing agent. Compound 1 (100 microM) and insulin (10 nM) did not show any synergistic effect on glucose uptake. These results suggest that the flavonoid may have a dual target of action, as an insulin-secretagogue and also as an insulin-mimetic agent.
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Affiliation(s)
- Luisa Helena Cazarolli
- Departamento de Bioquímica, Centro de Ciências Biológicas, UFSC, Campus Universitário, Bairro Trindade, Cx. Postal 5069, CEP: 88040-970 Florianópolis, SC, Brazil
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23
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News & views. Biotechnol J 2008. [DOI: 10.1002/biot.200890027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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