1
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Blocking AMPK β1 myristoylation enhances AMPK activity and protects mice from high-fat diet-induced obesity and hepatic steatosis. Cell Rep 2022; 41:111862. [PMID: 36543129 DOI: 10.1016/j.celrep.2022.111862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 10/07/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is a master regulator of cellular energy homeostasis and a therapeutic target for metabolic diseases. Co/post-translational N-myristoylation of glycine-2 (Gly2) of the AMPK β subunit has been suggested to regulate the distribution of the kinase between the cytosol and membranes through a "myristoyl switch" mechanism. However, the relevance of AMPK myristoylation for metabolic signaling in cells and in vivo is unclear. Here, we generated knockin mice with a Gly2-to-alanine point mutation of AMPKβ1 (β1-G2A). We demonstrate that non-myristoylated AMPKβ1 has reduced stability but is associated with increased kinase activity and phosphorylation of the Thr172 activation site in the AMPK α subunit. Using proximity ligation assays, we show that loss of β1 myristoylation impedes colocalization of the phosphatase PPM1A/B with AMPK in cells. Mice carrying the β1-G2A mutation have improved metabolic health with reduced adiposity, hepatic lipid accumulation, and insulin resistance under conditions of high-fat diet-induced obesity.
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2
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Structure-function analysis of the AMPK activator SC4 and identification of a potent pan AMPK activator. Biochem J 2022; 479:1181-1204. [PMID: 35552369 PMCID: PMC9317966 DOI: 10.1042/bcj20220067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022]
Abstract
The AMP-activated protein kinase (AMPK) αβγ heterotrimer is a primary cellular energy sensor and central regulator of energy homeostasis. Activating skeletal muscle AMPK with small molecule drugs improves glucose uptake and provides an opportunity for new strategies to treat type 2 diabetes and insulin resistance, with recent genetic and pharmacological studies indicating the α2β2γ1 isoform combination as the heterotrimer complex primarily responsible. With the goal of developing α2β2-specific activators, here we perform structure/function analysis of the 2-hydroxybiphenyl group of SC4, an activator with tendency for α2-selectivity that is also capable of potently activating β2 complexes. Substitution of the LHS 2-hydroxyphenyl group with polar-substituted cyclohexene-based probes resulted in two AMPK agonists, MSG010 and MSG011, which did not display α2-selectivity when screened against a panel of AMPK complexes. By radiolabel kinase assay, MSG010 and MSG011 activated α2β2γ1 AMPK with one order of magnitude greater potency than the pan AMPK activator MK-8722. A crystal structure of MSG011 complexed to AMPK α2β1γ1 revealed a similar binding mode to SC4 and the potential importance of an interaction between the SC4 2-hydroxyl group and α2-Lys31 for directing α2-selectivity. MSG011 induced robust AMPK signalling in mouse primary hepatocytes and commonly used cell lines, and in most cases this occurred in the absence of changes in phosphorylation of the kinase activation loop residue α-Thr172, a classical marker of AMP-induced AMPK activity. These findings will guide future design of α2β2-selective AMPK activators, that we hypothesise may avoid off-target complications associated with indiscriminate activation of AMPK throughout the body.
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3
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Xu B, Li Z, Zeng T, Zhan J, Wang S, Ho CT, Li S. Bioactives of Momordica charantia as Potential Anti-Diabetic/Hypoglycemic Agents. Molecules 2022; 27:2175. [PMID: 35408574 PMCID: PMC9000558 DOI: 10.3390/molecules27072175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/23/2022] [Accepted: 03/23/2022] [Indexed: 11/17/2022] Open
Abstract
Momordica charantia L., a member of the Curcubitaceae family, has traditionally been used as herbal medicine and as a vegetable. Functional ingredients of M. charantia play important roles in body health and human nutrition, which can be used directly or indirectly in treating or preventing hyperglycemia-related chronic diseases in humans. The hypoglycemic effects of M. charantia have been known for years. In this paper, the research progress of M. charantia phytobioactives and their hypoglycemic effects and related mechanisms, especially relating to diabetes mellitus, has been reviewed. Moreover, the clinical application of M. charantia in treating diabetes mellitus is also discussed, hoping to broaden the application of M. charantia as functional food.
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Affiliation(s)
- Bilin Xu
- College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang 438000, China; (B.X.); (Z.L.); (J.Z.); (S.W.)
| | - Zhiliang Li
- College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang 438000, China; (B.X.); (Z.L.); (J.Z.); (S.W.)
| | - Ting Zeng
- College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, China;
| | - Jianfeng Zhan
- College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang 438000, China; (B.X.); (Z.L.); (J.Z.); (S.W.)
| | - Shuzhen Wang
- College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang 438000, China; (B.X.); (Z.L.); (J.Z.); (S.W.)
| | - Chi-Tang Ho
- Department of Food Science, Rutgers University, New Brunswick, NJ 08901, USA;
| | - Shiming Li
- College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang 438000, China; (B.X.); (Z.L.); (J.Z.); (S.W.)
- Department of Food Science, Rutgers University, New Brunswick, NJ 08901, USA;
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4
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Morrison KR, Smiles WJ, Ling NXY, Hoque A, Shea G, Ngoei KRW, Yu D, Murray-Segal L, Scott JW, Galic S, Kemp BE, Petersen J, Oakhill JS. An AMPKα2-specific phospho-switch controls lysosomal targeting for activation. Cell Rep 2022; 38:110365. [PMID: 35172150 DOI: 10.1016/j.celrep.2022.110365] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/28/2021] [Accepted: 01/19/2022] [Indexed: 12/12/2022] Open
Abstract
AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin complex 1 (mTORC1) are metabolic kinases that co-ordinate nutrient supply with cell growth. AMPK negatively regulates mTORC1, and mTORC1 reciprocally phosphorylates S345/7 in both AMPK α-isoforms. We report that genetic or torin1-induced loss of α2-S345 phosphorylation relieves suppression of AMPK signaling; however, the regulatory effect does not translate to α1-S347 in HEK293T or MEF cells. Dephosphorylation of α2-S345, but not α1-S347, transiently targets AMPK to lysosomes, a cellular site for activation by LKB1. By mass spectrometry, we find that α2-S345 is basally phosphorylated at 2.5-fold higher stoichiometry than α1-S347 in HEK293T cells and, unlike α1, phosphorylation is partially retained after prolonged mTORC1 inhibition. Loss of α2-S345 phosphorylation in endogenous AMPK fails to sustain growth of MEFs under amino acid starvation conditions. These findings uncover an α2-specific mechanism by which AMPK can be activated at lysosomes in the absence of changes in cellular energy.
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Affiliation(s)
- Kaitlin R Morrison
- Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA 5042, Australia
| | - William J Smiles
- Metabolic Signalling Laboratory, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Naomi X Y Ling
- Metabolic Signalling Laboratory, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Ashfaqul Hoque
- Metabolic Signalling Laboratory, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Gabrielle Shea
- Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA 5042, Australia
| | - Kevin R W Ngoei
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Dingyi Yu
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Lisa Murray-Segal
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - John W Scott
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia; Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia; The Florey Institute of Neuroscience and Mental Health, Parkville, Melbourne, VIC 3052, Australia
| | - Sandra Galic
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia
| | - Bruce E Kemp
- Protein Chemistry & Metabolism Unit, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia; Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia
| | - Janni Petersen
- Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA 5042, Australia; Nutrition and Metabolism, South Australia Health and Medical Research Institute, Adelaide, SA, Australia.
| | - Jonathan S Oakhill
- Metabolic Signalling Laboratory, St Vincent's Institute of Medical Research, School of Medicine, University of Melbourne, Melbourne, VIC 3065, Australia.
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5
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McKay LK, White JP. The AMPK/p27 Kip1 Pathway as a Novel Target to Promote Autophagy and Resilience in Aged Cells. Cells 2021; 10:cells10061430. [PMID: 34201101 PMCID: PMC8229180 DOI: 10.3390/cells10061430] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 11/16/2022] Open
Abstract
Once believed to solely function as a cyclin-dependent kinase inhibitor, p27Kip1 is now emerging as a critical mediator of autophagy, cytoskeletal dynamics, cell migration and apoptosis. During periods of metabolic stress, the subcellular location of p27Kip1 largely dictates its function. Cytoplasmic p27Kip1 has been found to be promote cellular resilience through autophagy and anti-apoptotic mechanisms. Nuclear p27Kip1, however, inhibits cell cycle progression and makes the cell susceptible to quiescence, apoptosis, and/or senescence. Cellular location of p27Kip1 is regulated, in part, by phosphorylation by various kinases, including Akt and AMPK. Aging promotes nuclear localization of p27Kip1 and a predisposition to senescence or apoptosis. Here, we will review the role of p27Kip1 in healthy and aging cells with a particular emphasis on the interplay between autophagy and apoptosis.
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Affiliation(s)
- Lauren K. McKay
- Adams School of Dentistry, UNC Chapel Hill, Chapel Hill, NC 27599, USA;
- Duke Molecular Physiology Institute, Duke University School of Medicine, 300 N. Duke Street, Durham, NC 27701, USA
| | - James P. White
- Duke Molecular Physiology Institute, Duke University School of Medicine, 300 N. Duke Street, Durham, NC 27701, USA
- Department of Medicine, Duke University School of Medicine, 300 N. Duke Street, Durham, NC 27701, USA
- Duke Center for the Study of Aging and Human Development, Duke University School of Medicine, 300 N. Duke Street, Durham, NC 27701, USA
- Correspondence:
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6
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Ovens AJ, Scott JW, Langendorf CG, Kemp BE, Oakhill JS, Smiles WJ. Post-Translational Modifications of the Energy Guardian AMP-Activated Protein Kinase. Int J Mol Sci 2021; 22:ijms22031229. [PMID: 33513781 PMCID: PMC7866021 DOI: 10.3390/ijms22031229] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 01/13/2023] Open
Abstract
Physical exercise elicits physiological metabolic perturbations such as energetic and oxidative stress; however, a diverse range of cellular processes are stimulated in response to combat these challenges and maintain cellular energy homeostasis. AMP-activated protein kinase (AMPK) is a highly conserved enzyme that acts as a metabolic fuel sensor and is central to this adaptive response to exercise. The complexity of AMPK’s role in modulating a range of cellular signalling cascades is well documented, yet aside from its well-characterised regulation by activation loop phosphorylation, AMPK is further subject to a multitude of additional regulatory stimuli. Therefore, in this review we comprehensively outline current knowledge around the post-translational modifications of AMPK, including novel phosphorylation sites, as well as underappreciated roles for ubiquitination, sumoylation, acetylation, methylation and oxidation. We provide insight into the physiological ramifications of these AMPK modifications, which not only affect its activity, but also subcellular localisation, nutrient interactions and protein stability. Lastly, we highlight the current knowledge gaps in this area of AMPK research and provide perspectives on how the field can apply greater rigour to the characterisation of novel AMPK regulatory modifications.
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Affiliation(s)
- Ashley J. Ovens
- Metabolic Signalling Laboratory, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia; (A.J.O.); (J.S.O.)
- Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia; (J.W.S.); (B.E.K.)
| | - John W. Scott
- Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia; (J.W.S.); (B.E.K.)
- Protein Chemistry & Metabolism, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia;
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC 3052, Australia
| | - Christopher G. Langendorf
- Protein Chemistry & Metabolism, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia;
| | - Bruce E. Kemp
- Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia; (J.W.S.); (B.E.K.)
- Protein Chemistry & Metabolism, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia;
| | - Jonathan S. Oakhill
- Metabolic Signalling Laboratory, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia; (A.J.O.); (J.S.O.)
- Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, VIC 3000, Australia; (J.W.S.); (B.E.K.)
| | - William J. Smiles
- Metabolic Signalling Laboratory, St Vincent’s Institute of Medical Research, School of Medicine, University of Melbourne, Fitzroy, VIC 3065, Australia; (A.J.O.); (J.S.O.)
- Correspondence:
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7
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Abstract
Regulation of AMP-activated protein kinase (AMPK) signalling is complex and involves contributions from adenine nucleotides, co-/posttranslational modifications, and isoform composition of the AMPK heterotrimer. It is becoming apparent that AMPK activation/inhibition by synthetic drugs involves similar levels of complexity. Major advances in our understanding of these mechanisms have been gained from recombinant expression systems that provide sufficient quantities of highly purified material for structure/function studies. Here, we provide a detailed protocol for transient expression of affinity-tagged AMPK complexes in mammalian cells. We have found this system to be optimal as a source of enzyme possessing regulatory modifications found in vivo.
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8
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Kjøbsted R, Hingst JR, Fentz J, Foretz M, Sanz MN, Pehmøller C, Shum M, Marette A, Mounier R, Treebak JT, Wojtaszewski JFP, Viollet B, Lantier L. AMPK in skeletal muscle function and metabolism. FASEB J 2018; 32:1741-1777. [PMID: 29242278 PMCID: PMC5945561 DOI: 10.1096/fj.201700442r] [Citation(s) in RCA: 256] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Skeletal muscle possesses a remarkable ability to adapt to various physiologic conditions. AMPK is a sensor of intracellular energy status that maintains energy stores by fine-tuning anabolic and catabolic pathways. AMPK’s role as an energy sensor is particularly critical in tissues displaying highly changeable energy turnover. Due to the drastic changes in energy demand that occur between the resting and exercising state, skeletal muscle is one such tissue. Here, we review the complex regulation of AMPK in skeletal muscle and its consequences on metabolism (e.g., substrate uptake, oxidation, and storage as well as mitochondrial function of skeletal muscle fibers). We focus on the role of AMPK in skeletal muscle during exercise and in exercise recovery. We also address adaptations to exercise training, including skeletal muscle plasticity, highlighting novel concepts and future perspectives that need to be investigated. Furthermore, we discuss the possible role of AMPK as a therapeutic target as well as different AMPK activators and their potential for future drug development.—Kjøbsted, R., Hingst, J. R., Fentz, J., Foretz, M., Sanz, M.-N., Pehmøller, C., Shum, M., Marette, A., Mounier, R., Treebak, J. T., Wojtaszewski, J. F. P., Viollet, B., Lantier, L. AMPK in skeletal muscle function and metabolism.
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Affiliation(s)
- Rasmus Kjøbsted
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Janne R Hingst
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Joachim Fentz
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Marc Foretz
- INSERM, Unité 1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Maria-Nieves Sanz
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland, and.,Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Christian Pehmøller
- Internal Medicine Research Unit, Pfizer Global Research and Development, Cambridge, Massachusetts, USA
| | - Michael Shum
- Axe Cardiologie, Quebec Heart and Lung Research Institute, Laval University, Québec, Canada.,Institute for Nutrition and Functional Foods, Laval University, Québec, Canada
| | - André Marette
- Axe Cardiologie, Quebec Heart and Lung Research Institute, Laval University, Québec, Canada.,Institute for Nutrition and Functional Foods, Laval University, Québec, Canada
| | - Remi Mounier
- Institute NeuroMyoGène, Université Claude Bernard Lyon 1, INSERM Unité 1217, CNRS UMR, Villeurbanne, France
| | - Jonas T Treebak
- Section of Integrative Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen F P Wojtaszewski
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Benoit Viollet
- INSERM, Unité 1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Louise Lantier
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA.,Mouse Metabolic Phenotyping Center, Vanderbilt University, Nashville, Tennessee, USA
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9
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Ward J, Reyes AR, Kurumbail RG. Allosteric Modulation of AMPK Enzymatic Activity: In Vitro Characterization. Methods Enzymol 2016; 587:481-509. [PMID: 28253974 DOI: 10.1016/bs.mie.2016.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AMP-activated protein kinase (AMPK) is a heterotrimeric serine/threonine protein kinase found in nearly all eukaryotes that functions as a master energy sensor in cells. During times of cell stress and changes in the AMP/ATP ratio, AMPK becomes activated and phosphorylates a multitude of protein substrates involved in various cellular processes such as metabolism, cell growth and autophagy. The endogenous ligand AMP is known to bind to the γ-subunit and activates the enzyme via three distinct mechanisms (1) enhancing phosphorylation by upstream kinases of Thr172 in the activation loop (a site critical for AMPK activity), (2) protecting Thr172 from dephosphorylation by phosphatases, and (3) allosteric activation of the kinase activity. Given the important regulatory role for AMPK in various cellular processes and the multiple known modes of activation, there is great interest in identifying small-molecule activators of this kinase and a need for assays to identify and characterize compounds. Here we describe several assay formats that have been used for identifying and characterizing small-molecule AMPK activators.
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Affiliation(s)
- J Ward
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA, United States.
| | - A R Reyes
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA, United States
| | - R G Kurumbail
- Worldwide Medicinal Chemistry, Pfizer Worldwide Research and Development, Groton, CT, United States
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10
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Jiang S, Park DW, Stigler WS, Creighton J, Ravi S, Darley-Usmar V, Zmijewski JW. Mitochondria and AMP-activated protein kinase-dependent mechanism of efferocytosis. J Biol Chem 2013; 288:26013-26026. [PMID: 23897815 DOI: 10.1074/jbc.m113.489468] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Defective clearance of apoptotic cells is frequently associated with perpetuation of inflammatory conditions. Our results show a rapid activation of AMP-activated kinase (AMPK) in macrophages upon exposure to apoptotic cells or lysophosphatidylcholine, a specific phospholipid that is produced and released from dying cells. AMPK activation resulted from inhibition of mitochondrial oxygen consumption and ATP production and further depended on Ca(2+) mobilization and mitochondrial reactive oxygen species generation. Once activated, AMPK increased microtubule synthesis and chemokinesis and provided adaptation to energy demand during tracking and engulfment. Uptake of apoptotic cells was increased in lungs of mice that received lysophosphatidylcholine. Furthermore, inhibition of AMPK diminished clearance of apoptotic thymocytes in vitro and in dexamethasone-treated mice. Taken together, we conclude that the mitochondrial AMPK axis is a sensor and enhancer of tracking and removal of apoptotic cell, processes crucial to resolution of inflammatory conditions and a return to tissue homeostasis.
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Affiliation(s)
| | - Dae Won Park
- From the Department of Medicine,; the Division of Infectious Diseases, Korea University Ansan Hospital, Ansan 425-707, Republic of Korea
| | | | | | | | - Victor Darley-Usmar
- Department of Pathology, and; Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0012 and
| | - Jaroslaw W Zmijewski
- From the Department of Medicine,; Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0012 and.
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11
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Sanz P, Rubio T, Garcia-Gimeno MA. AMPKbeta subunits: more than just a scaffold in the formation of AMPK complex. FEBS J 2013; 280:3723-33. [DOI: 10.1111/febs.12364] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 05/15/2013] [Accepted: 05/29/2013] [Indexed: 12/16/2022]
Affiliation(s)
- Pascual Sanz
- Instituto de Biomedicina de Valencia; CSIC and Centro de Investigación en Red de Enfermedades Raras (CIBERER); Spain
| | - Teresa Rubio
- Instituto de Biomedicina de Valencia; CSIC and Centro de Investigación en Red de Enfermedades Raras (CIBERER); Spain
| | - Maria Adelaida Garcia-Gimeno
- Instituto de Biomedicina de Valencia; CSIC and Centro de Investigación en Red de Enfermedades Raras (CIBERER); Spain
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12
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Iseli TJ, Turner N, Zeng XY, Cooney GJ, Kraegen EW, Yao S, Ye Y, James DE, Ye JM. Activation of AMPK by bitter melon triterpenoids involves CaMKKβ. PLoS One 2013; 8:e62309. [PMID: 23638033 PMCID: PMC3636144 DOI: 10.1371/journal.pone.0062309] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 03/19/2013] [Indexed: 01/11/2023] Open
Abstract
We recently showed that bitter melon-derived triterpenoids (BMTs) activate AMPK and increase GLUT4 translocation to the plasma membrane in vitro, and improve glucose disposal in insulin resistant models in vivo. Here we interrogated the mechanism by which these novel compounds activate AMPK, a leading anti-diabetic drug target. BMTs did not activate AMPK directly in an allosteric manner as AMP or the Abbott compound (A-769662) does, nor did they activate AMPK by inhibiting cellular respiration like many commonly used anti-diabetic medications. BMTs increased AMPK activity in both L6 myotubes and LKB1-deficient HeLa cells by 20–35%. Incubation with the CaMKKβ inhibitor, STO-609, completely attenuated this effect suggesting a key role for CaMKKβ in this activation. Incubation of L6 myotubes with the calcium chelator EGTA-AM did not alter this activation suggesting that the BMT-dependent activation was Ca2+-independent. We therefore propose that CaMKKβ is a key upstream kinase for BMT-induced activation of AMPK.
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Affiliation(s)
- Tristan J. Iseli
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Nigel Turner
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Xiao-Yi Zeng
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
- Health Innovations Research Institute and School of Health Sciences, RMIT University, Melbourne, Australia
| | - Gregory J. Cooney
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Edward W. Kraegen
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Sheng Yao
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Yang Ye
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - David E. James
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Ji-Ming Ye
- Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, Australia
- Health Innovations Research Institute and School of Health Sciences, RMIT University, Melbourne, Australia
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- * E-mail:
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13
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Sanli T, Linher-Melville K, Tsakiridis T, Singh G. Sestrin2 modulates AMPK subunit expression and its response to ionizing radiation in breast cancer cells. PLoS One 2012; 7:e32035. [PMID: 22363791 PMCID: PMC3282792 DOI: 10.1371/journal.pone.0032035] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 01/18/2012] [Indexed: 12/20/2022] Open
Abstract
Background The sestrin family of stress-responsive genes (SESN1-3) are suggested to be involved in regulation of metabolism and aging through modulation of the AMPK-mTOR pathway. AMP-activated protein kinase (AMPK) is an effector of the tumour suppressor LKB1, which regulates energy homeostasis, cell polarity, and the cell cycle. SESN1/2 can interact directly with AMPK in response to stress to maintain genomic integrity and suppress tumorigenesis. Ionizing radiation (IR), a widely used cancer therapy, is known to increase sestrin expression, and acutely activate AMPK. However, the regulation of AMPK expression by sestrins in response to IR has not been studied in depth. Methods and Findings Through immunoprecipitation we observed that SESN2 directly interacted with the AMPKα1β1γ1 trimer and its upstream regulator LKB1 in MCF7 breast cancer cells. SESN2 overexpression was achieved using a Flag-tagged SESN2 expression vector or a stably-integrated tetracycline-inducible system, which also increased AMPKα1 and AMPKβ1 subunit phosphorylation, and co-localized with phosphorylated AMPKα-Thr127 in the cytoplasm. Furthermore, enhanced SESN2 expression increased protein levels of LKB1 and AMPKα1β1γ1, as well as mRNA levels of LKB1, AMPKα1, and AMPKβ1. Treatment of MCF7 cells with IR elevated AMPK expression and activity, but this effect was attenuated in the presence of SESN2 siRNA. In addition, elevated SESN2 inhibited IR-induced mTOR signalling and sensitized MCF7 cells to IR through an AMPK-dependent mechanism. Conclusions Our results suggest that in breast cancer cells SESN2 is associated with AMPK, it is involved in regulation of basal and IR-induced expression and activation of this enzyme, and it mediates sensitization of cancer cells to IR.
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Affiliation(s)
- Toran Sanli
- Research Department, Juravinski Cancer Center, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Katja Linher-Melville
- Research Department, Juravinski Cancer Center, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | | | - Gurmit Singh
- Research Department, Juravinski Cancer Center, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
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14
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Bae HB, Zmijewski JW, Deshane JS, Tadie JM, Chaplin DD, Takashima S, Abraham E. AMP-activated protein kinase enhances the phagocytic ability of macrophages and neutrophils. FASEB J 2011; 25:4358-68. [PMID: 21885655 DOI: 10.1096/fj.11-190587] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Although AMPK plays well-established roles in the modulation of energy balance, recent studies have shown that AMPK activation has potent anti-inflammatory effects. In the present experiments, we examined the role of AMPK in phagocytosis. We found that ingestion of Escherichia coli or apoptotic cells by macrophages increased AMPK activity. AMPK activation increased the ability of neutrophils or macrophages to ingest bacteria (by 46 ± 7.8 or 85 ± 26%, respectively, compared to control, P<0.05) and the ability of macrophages to ingest apoptotic cells (by 21 ± 1.4%, P<0.05 compared to control). AMPK activation resulted in cytoskeletal reorganization, including enhanced formation of actin and microtubule networks. Activation of PAK1/2 and WAVE2, which are downstream effectors of Rac1, accompanied AMPK activation. AMPK activation also induced phosphorylation of CLIP-170, a protein that participates in microtubule synthesis. The increase in phagocytosis was reversible by the specific AMPK inhibitor compound C, siRNA to AMPKα1, Rac1 inhibitors, or agents that disrupt actin or microtubule networks. In vivo, AMPK activation resulted in enhanced phagocytosis of bacteria in the lungs by 75 ± 5% vs. control (P<0.05). These results demonstrate a novel function for AMPK in enhancing the phagocytic activity of neutrophils and macrophages.
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Affiliation(s)
- Hong-Beom Bae
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
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15
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Murphy RM. Enhanced technique to measure proteins in single segments of human skeletal muscle fibers: fiber-type dependence of AMPK-alpha1 and -beta1. J Appl Physiol (1985) 2010; 110:820-5. [PMID: 21088205 DOI: 10.1152/japplphysiol.01082.2010] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Human physiological studies typically use skeletal muscle biopsies from the heterogeneous vastus lateralis muscle comprised of both fast-twitch and slow-twitch fiber types. It is likely that potential changes of physiological importance are overlooked because fiber-type specific responses may not be apparent in the whole muscle preparation. A technological advance in Western blotting is presented where proteins are analyzed in just one small segment (<2 mm) of individual fibers dissected from freeze-dried muscle samples using standard laboratory equipment. A significant advance is being able to classify every fiber at the level of both contractile (myosin heavy chain and tropomyosin) and sarcoplasmic reticulum [sarco(endo)plasmic reticulum Ca(2+)-ATPase type 1] properties and then being able to measure specific proteins in the very same segments. This removes the need to fiber type segments before further analyses and, as such, dramatically reduces the time required for sample collection. Compared with slow-twitch fibers, there was less AMP-activated protein kinase (AMPK)-α(1) (∼25%) and AMPK-β(1) (∼60%) in fast-twitch fibers from human skeletal muscle biopsies.
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Affiliation(s)
- Robyn M Murphy
- Department of Zoology, La Trobe Univ., Melbourne, Victoria 3086, Australia.
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16
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β-Subunit myristoylation is the gatekeeper for initiating metabolic stress sensing by AMP-activated protein kinase (AMPK). Proc Natl Acad Sci U S A 2010; 107:19237-41. [PMID: 20974912 DOI: 10.1073/pnas.1009705107] [Citation(s) in RCA: 242] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) is an αβγ heterotrimer that acts as a master metabolic regulator to maintain cellular energy balance following increased energy demand and increases in the AMP/ATP ratio. This regulation provides dynamic control of energy metabolism, matching energy supply with demand that is essential for the function and survival of organisms. AMPK is inactive unless phosphorylated on Thr172 in the α-catalytic subunit activation loop by upstream kinases (LKB1 or calcium-calmodulin-dependent protein kinase kinase β). How a rise in AMP levels triggers AMPK α-Thr172 phosphorylation and activation is incompletely understood. Here we demonstrate unequivocally that AMP directly stimulates α-Thr172 phosphorylation provided the AMPK β-subunit is myristoylated. Loss of the myristoyl group abolishes AMP activation and reduces the extent of α-Thr172 phosphorylation. Once AMPK is phosphorylated, AMP further activates allosterically but this activation does not require β-subunit myristoylation. AMP and glucose deprivation also promote membrane association of myristoylated AMPK, indicative of a myristoyl-switch mechanism. Our results show that AMP regulates AMPK activation at the initial phosphorylation step, and that β-subunit myristoylation is important for transducing the metabolic stress signal.
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17
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Dzamko N, van Denderen BJW, Hevener AL, Jørgensen SB, Honeyman J, Galic S, Chen ZP, Watt MJ, Campbell DJ, Steinberg GR, Kemp BE. AMPK beta1 deletion reduces appetite, preventing obesity and hepatic insulin resistance. J Biol Chem 2009; 285:115-22. [PMID: 19892703 DOI: 10.1074/jbc.m109.056762] [Citation(s) in RCA: 143] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The AMP-activated protein kinase (AMPK) is an alphabetagamma heterotrimer that regulates appetite and fuel metabolism. We have generated AMPK beta1(-/-) mice on a C57Bl/6 background that are viable, fertile, survived greater than 2 years, and display no visible brain developmental defects. These mice have a 90% reduction in hepatic AMPK activity due to loss of the catalytic alpha subunits, with modest reductions of activity detected in the hypothalamus and white adipose tissue and no change in skeletal muscle or heart. On a low fat or an obesity-inducing high fat diet, beta1(-/-) mice had reduced food intake, reduced adiposity, and reduced total body mass. Metabolic rate, physical activity, adipose tissue lipolysis, and lipogenesis were similar to wild type littermates. The reduced appetite and body mass of beta1(-/-) mice were associated with protection from high fat diet-induced hyperinsulinemia, hepatic steatosis, and insulin resistance. We demonstrate that the loss of beta1 reduces food intake and protects against the deleterious effects of an obesity-inducing diet.
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Affiliation(s)
- Nicolas Dzamko
- Department of Medicine, St Vincent's Institute of Medical Research, University of Melbourne, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia
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18
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On computational approaches for size-and-shape distributions from sedimentation velocity analytical ultracentrifugation. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2009; 39:1261-75. [PMID: 19806353 PMCID: PMC2892069 DOI: 10.1007/s00249-009-0545-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 09/08/2009] [Accepted: 09/14/2009] [Indexed: 11/06/2022]
Abstract
Sedimentation velocity analytical ultracentrifugation has become a very popular technique to study size distributions and interactions of macromolecules. Recently, a method termed two-dimensional spectrum analysis (2DSA) for the determination of size-and-shape distributions was described by Demeler and colleagues (Eur Biophys J 2009). It is based on novel ideas conceived for fitting the integral equations of the size-and-shape distribution to experimental data, illustrated with an example but provided without proof of the principle of the algorithm. In the present work, we examine the 2DSA algorithm by comparison with the mathematical reference frame and simple well-known numerical concepts for solving Fredholm integral equations, and test the key assumptions underlying the 2DSA method in an example application. While the 2DSA appears computationally excessively wasteful, key elements also appear to be in conflict with mathematical results. This raises doubts about the correctness of the results from 2DSA analysis.
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19
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Abstract
The function and survival of all organisms is dependent on the dynamic control of energy metabolism, when energy demand is matched to energy supply. The AMP-activated protein kinase (AMPK) alphabetagamma heterotrimer has emerged as an important integrator of signals that control energy balance through the regulation of multiple biochemical pathways in all eukaryotes. In this review, we begin with the discovery of the AMPK family and discuss the recent structural studies that have revealed the molecular basis for AMP binding to the enzyme's gamma subunit. AMPK's regulation involves autoinhibitory features and phosphorylation of both the catalytic alpha subunit and the beta-targeting subunit. We review the role of AMPK at the cellular level through examination of its many substrates and discuss how it controls cellular energy balance. We look at how AMPK integrates stress responses such as exercise as well as nutrient and hormonal signals to control food intake, energy expenditure, and substrate utilization at the whole body level. Lastly, we review the possible role of AMPK in multiple common diseases and the role of the new age of drugs targeting AMPK signaling.
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Affiliation(s)
- Gregory R Steinberg
- Protein Chemistry and Metabolism, St. Vincent's Institute of Medical Research, University of Melbourne, Fitzroy, Victoria, Australia.
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20
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Polymorphisms in the promoter region of bovine PRKAB1 gene. Mol Biol Rep 2009; 37:435-40. [DOI: 10.1007/s11033-009-9612-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2008] [Accepted: 07/01/2009] [Indexed: 10/20/2022]
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21
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Single Nucleotide Polymorphisms and Haplotypic Diversity in the Bovine PRKAB1 Gene. Mol Biotechnol 2009; 43:193-9. [DOI: 10.1007/s12033-009-9194-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2009] [Accepted: 06/09/2009] [Indexed: 10/20/2022]
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Abstract
AMP-activated protein kinase (AMPK) regulates metabolism in response to energy demand and supply. AMPK is activated in response to rises in intracellular AMP or calcium-mediated signalling and is responsible for phosphorylating a wide variety of substrates. Recent structural studies have revealed the architecture of the alphabetagamma subunit interactions as well as the AMP binding pockets on the gamma subunit. The alpha catalytic domain (1-280) is autoinhibited by a C-terminal tail (313-335), which is proposed to interact with the small lobe of the catalytic domain by homology modelling with the MARK2 protein structure. Two direct activating drugs have been reported for AMPK, the thienopyridone compound A769662 and PTI, which may activate by distinct mechanisms.
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Affiliation(s)
- J S Oakhill
- St Vincent's Institute and Department of Medicine University of Melbourne, Fitzroy, Victoria, Australia
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23
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Mollica JP, Oakhill JS, Lamb GD, Murphy RM. Are genuine changes in protein expression being overlooked? Reassessing Western blotting. Anal Biochem 2009; 386:270-5. [DOI: 10.1016/j.ab.2008.12.029] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 12/22/2008] [Accepted: 12/29/2008] [Indexed: 10/21/2022]
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Chen Z, Peng IC, Sun W, Su MI, Hsu PH, Fu Y, Zhu Y, DeFea K, Pan S, Tsai MD, Shyy JYJ. AMP-activated protein kinase functionally phosphorylates endothelial nitric oxide synthase Ser633. Circ Res 2009; 104:496-505. [PMID: 19131647 DOI: 10.1161/circresaha.108.187567] [Citation(s) in RCA: 211] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Endothelial nitric oxide synthase (eNOS) plays a central role in maintaining cardiovascular homeostasis by controlling NO bioavailability. The activity of eNOS in vascular endothelial cells (ECs) largely depends on posttranslational modifications, including phosphorylation. Because the activity of AMP-activated protein kinase (AMPK) in ECs can be increased by multiple cardiovascular events, we studied the phosphorylation of eNOS Ser633 by AMPK and examined its functional relevance in the mouse models. Shear stress, atorvastatin, and adiponectin all increased AMPK Thr172 and eNOS Ser633 phosphorylations, which were abolished if AMPK was pharmacologically inhibited or genetically ablated. The constitutively active form of AMPK or an AMPK agonist caused a sustained Ser633 phosphorylation. Expression of gain-/loss-of-function eNOS mutants revealed that Ser633 phosphorylation is important for NO production. The aorta of AMPKalpha2(-/-) mice showed attenuated atorvastatin-induced eNOS phosphorylation. Nano-liquid chromatography/tandem mass spectrometry (LC/MS/MS) confirmed that eNOS Ser633 was able to compete with Ser1177 or acetyl-coenzyme A carboxylase Ser79 for AMPKalpha phosphorylation. Nano-LC/MS/MS confirmed that eNOS purified from AICAR-treated ECs was phosphorylated at both Ser633 and Ser1177. Our results indicate that AMPK phosphorylation of eNOS Ser633 is a functional signaling event for NO bioavailability in ECs.
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Affiliation(s)
- Zhen Chen
- Division of Biomedical Sciences, University of California, Riverside, CA 92521, USA
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25
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Dzamko N, Schertzer JD, Ryall JG, Steel R, Macaulay SL, Wee S, Chen ZP, Michell BJ, Oakhill JS, Watt MJ, Jørgensen SB, Lynch GS, Kemp BE, Steinberg GR. AMPK-independent pathways regulate skeletal muscle fatty acid oxidation. J Physiol 2008; 586:5819-31. [PMID: 18845612 DOI: 10.1113/jphysiol.2008.159814] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The activation of AMP-activated protein kinase (AMPK) and phosphorylation/inhibition of acetyl-CoA carboxylase 2 (ACC2) is believed to be the principal pathway regulating fatty acid oxidation. However, during exercise AMPK activity and ACC Ser-221 phosphorylation does not always correlate with rates of fatty acid oxidation. To address this issue we have investigated the requirement for skeletal muscle AMPK in controlling aminoimidazole-4-carboxymide-1-beta-d-ribofuranoside (AICAR) and contraction-stimulated fatty acid oxidation utilizing transgenic mice expressing a muscle-specific kinase dead (KD) AMPK alpha2. In wild-type (WT) mice, AICAR and contraction increased AMPK alpha2 and alpha1 activities, the phosphorylation of ACC2 and rates of fatty acid oxidation while tending to reduce malonyl-CoA levels. Despite no activation of AMPK in KD mice, ACC2 phosphorylation was maintained, malonyl-CoA levels were reduced and rates of fatty acid oxidation were comparable between genotypes. During treadmill exercise both KD and WT mice had similar values of respiratory exchange ratio. These studies suggested the presence of an alternative ACC2 kinase(s). Using a phosphoproteomics-based approach we identified 18 Ser/Thr protein kinases whose phosphorylation was increased by greater than 25% in contracted KD relative to WT muscle. Utilizing bioinformatics we predicted that extracellular regulated protein-serine kinase (ERK1/2), inhibitor of nuclear factor (NF)-kappaB protein-serine kinase beta (IKKbeta) and protein kinase D (PKD) may phosphorylate ACC2 at Ser-221 but during in vitro phosphorylation assays only AMPK phosphorylated ACC2. These data demonstrate that AMPK is not essential for the regulation of fatty acid oxidation by AICAR or muscle contraction.
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Affiliation(s)
- Nicolas Dzamko
- St Vincent's Institute, 9 Princes Street, Fitzroy, Victoria 3065, Australia.
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