1
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Piserchio A, Dalby KN, Ghose R. Revealing eEF-2 kinase: recent structural insights into function. Trends Biochem Sci 2024; 49:169-182. [PMID: 38103971 PMCID: PMC10950556 DOI: 10.1016/j.tibs.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023]
Abstract
The α-kinase eukaryotic elongation factor 2 kinase (eEF-2K) regulates translational elongation by phosphorylating its ribosome-associated substrate, the GTPase eEF-2. eEF-2K is activated by calmodulin (CaM) through a distinctive mechanism unlike that in other CaM-dependent kinases (CAMK). We describe recent structural insights into this unique activation process and examine the effects of specific regulatory signals on this mechanism. We also highlight key unanswered questions to guide future structure-function studies. These include structural mechanisms which enable eEF-2K to interact with upstream/downstream partners and facilitate its integration of diverse inputs, including Ca2+ transients, phosphorylation mediated by energy/nutrient-sensing pathways, pH changes, and metabolites. Answering these questions is key to establishing how eEF-2K harmonizes translation with cellular requirements within the boundaries of its molecular landscape.
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Affiliation(s)
- Andrea Piserchio
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA
| | - Kevin N Dalby
- Division of Chemical Biology and Medicinal Chemistry, The University of Texas, Austin, TX 78712, USA.
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; The Graduate Center of The City University of New York (CUNY), New York, NY 10016, USA.
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2
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Kasica NP, Zhou X, Jester HM, Holland CE, Ryazanov AG, Forshaw TE, Furdui CM, Ma T. Homozygous knockout of eEF2K alleviates cognitive deficits in APP/PS1 Alzheimer’s disease model mice independent of brain amyloid β pathology. Front Aging Neurosci 2022; 14:959326. [PMID: 36158543 PMCID: PMC9500344 DOI: 10.3389/fnagi.2022.959326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/23/2022] [Indexed: 11/25/2022] Open
Abstract
Maintenance of memory and synaptic plasticity depends on de novo protein synthesis, and accumulating evidence implicates a role of dysregulated mRNA translation in cognitive impairments associated with Alzheimer’s disease (AD). Accumulating evidence demonstrates hyper-phosphorylation of translation factor eukaryotic elongation factor 2 (eEF2) in the hippocampi of human AD patients as well as transgenic AD model mice. Phosphorylation of eEF2 (at the Thr 56 site) by its only known kinase, eEF2K, leads to inhibition of general protein synthesis. A recent study suggests that amyloid β (Aβ)-induced neurotoxicity could be associated with an interaction between eEF2 phosphorylation and the transcription factor nuclear erythroid 2-related factor (NRF2)-mediated antioxidant response. In this brief communication, we report that global homozygous knockout of the eEF2K gene alleviates deficits of long-term recognition and spatial learning in a mouse model of AD (APP/PS1). Moreover, eEF2K knockout does not alter brain Aβ pathology in APP/PS1 mice. The hippocampal NRF2 antioxidant response in the APP/PS1 mice, measured by expression levels of nicotinamide adenine dinucleotide plus hydrogen (NADPH) quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1), is ameliorated by suppression of eEF2K signaling. Together, the findings may contribute to our understanding of the molecular mechanisms underlying AD pathogenesis, indicating that suppression of eEF2K activity could be a beneficial therapeutic option for this devastating neurodegenerative disease.
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Affiliation(s)
- Nicole P. Kasica
- Department of Internal Medicine, Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Xueyan Zhou
- Department of Internal Medicine, Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Hannah M. Jester
- Department of Internal Medicine, Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Caroline E. Holland
- Department of Internal Medicine, Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Alexey G. Ryazanov
- Department of Pharmacology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, United States
| | - Tom E. Forshaw
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Cristina M. Furdui
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Tao Ma
- Department of Internal Medicine, Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine, Winston-Salem, NC, United States
- *Correspondence: Tao Ma,
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3
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Zhdanov AV, Golubeva AV, Yordanova MM, Andreev DE, Ventura-Silva AP, Schellekens H, Baranov PV, Cryan JF, Papkovsky DB. Ghrelin rapidly elevates protein synthesis in vitro by employing the rpS6K-eEF2K-eEF2 signalling axis. Cell Mol Life Sci 2022; 79:426. [PMID: 35841486 PMCID: PMC9288388 DOI: 10.1007/s00018-022-04446-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 06/16/2022] [Accepted: 06/22/2022] [Indexed: 11/27/2022]
Abstract
Activated ghrelin receptor GHS-R1α triggers cell signalling pathways that modulate energy homeostasis and biosynthetic processes. However, the effects of ghrelin on mRNA translation are unknown. Using various reporter assays, here we demonstrate a rapid elevation of protein synthesis in cells within 15–30 min upon stimulation of GHS-R1α by ghrelin. We further show that ghrelin-induced activation of translation is mediated, at least in part, through the de-phosphorylation (de-suppression) of elongation factor 2 (eEF2). The levels of eEF2 phosphorylation at Thr56 decrease due to the reduced activity of eEF2 kinase, which is inhibited via Ser366 phosphorylation by rpS6 kinases. Being stress-susceptible, the ghrelin-mediated decrease in eEF2 phosphorylation can be abolished by glucose deprivation and mitochondrial uncoupling. We believe that the observed burst of translation benefits rapid restocking of neuropeptides, which are released upon GHS-R1α activation, and represents the most time- and energy-efficient way of prompt recharging the orexigenic neuronal circuitry.
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Affiliation(s)
- Alexander V Zhdanov
- School of Biochemistry & Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork, Ireland.
| | - Anna V Golubeva
- Department of Anatomy & Neuroscience, University College Cork, Cork, Ireland
| | - Martina M Yordanova
- School of Biochemistry & Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork, Ireland
| | - Dmitry E Andreev
- Belozersky Research Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russia
| | - Ana Paula Ventura-Silva
- APC Microbiome Institute, University College Cork, Cork, Ireland.,School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland
| | - Harriet Schellekens
- Department of Anatomy & Neuroscience, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Pavel V Baranov
- School of Biochemistry & Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork, Ireland
| | - John F Cryan
- Department of Anatomy & Neuroscience, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Dmitri B Papkovsky
- School of Biochemistry & Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork, Ireland
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4
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Elongation factor eEF2 kinase and autophagy jointly promote survival of cancer cells. Biochem J 2021; 478:1547-1569. [PMID: 33779695 DOI: 10.1042/bcj20210126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/22/2021] [Accepted: 03/29/2021] [Indexed: 01/07/2023]
Abstract
Cells within solid tumours can become deprived of nutrients; in order to survive, they need to invoke mechanisms to conserve these resources. Using cancer cells in culture in the absence of key nutrients, we have explored the roles of two potential survival mechanisms, autophagy and elongation factor 2 kinase (eEF2K), which, when activated, inhibits the resource-intensive elongation stage of protein synthesis. Both processes are regulated through the nutrient-sensitive AMP-activated protein kinase and mechanistic target of rapamycin complex 1 signalling pathways. We find that disabling both autophagy and eEF2K strongly compromises the survival of nutrient-deprived lung and breast cancer cells, whereas, for example, knocking out eEF2K alone has little effect. Contrary to some earlier reports, we find no evidence that eEF2K regulates autophagy. Unexpectedly, eEF2K does not facilitate survival of prostate cancer PC3 cells. Thus, eEF2K and autophagy enable survival of certain cell-types in a mutually complementary manner. To explore this further, we generated, by selection, cells which were able to survive nutrient starvation even when autophagy and eEF2K were disabled. Proteome profiling using mass spectrometry revealed that these 'resistant' cells showed lower levels of diverse proteins which are required for energy-consuming processes such as protein and fatty acid synthesis, although different clones of 'resistant cells' appear to adapt in dissimilar ways. Our data provide further information of the ways that human cells cope with nutrient limitation and to understanding of the utility of eEF2K as a potential target in oncology.
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5
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Comert Onder F, Kahraman N, Bellur Atici E, Cagir A, Kandemir H, Tatar G, Taskin Tok T, Kara G, Karliga B, Durdagi S, Ay M, Ozpolat B. Target-Driven Design of a Coumarinyl Chalcone Scaffold Based Novel EF2 Kinase Inhibitor Suppresses Breast Cancer Growth In Vivo. ACS Pharmacol Transl Sci 2021; 4:926-940. [PMID: 33860211 DOI: 10.1021/acsptsci.1c00030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Indexed: 11/28/2022]
Abstract
Eukaryotic elongation factor 2 kinase (eEF-2K) is an unusual alpha kinase involved in protein synthesis through phosphorylation of elongation factor 2 (EF2). eEF-2K is highly overexpressed in breast cancer, and its activity is associated with significantly shortened patient survival and proven to be a potential molecular target in breast cancer. The crystal structure of eEF-2K remains unknown, and there is no potent, safe, and effective inhibitor available for clinical applications. We designed and synthesized several generations of potential inhibitors. The effect of the inhibitors at the binding pocket of eEF-2K was analyzed after developing a 3D target model by using a domain of another α-kinase called myosin heavy-chain kinase A (MHCKA) that closely resembles eEF-2K. In silico studies showed that compounds with a coumarin-chalcone core have high predicted binding affinities for eEF-2K. Using in vitro studies in highly aggressive and invasive (MDA-MB-436, MDA-MB-231, and BT20) and noninvazive (MCF-7) breast cancer cells, we identified a lead compound that was highly effective in inhibiting eEF-2K activity at submicromolar concentrations and at inhibiting cell proliferation by induction of apoptosis with no toxicity in normal breast epithelial cells. In vivo systemic administration of the lead compound encapsulated in single lipid-based liposomal nanoparticles twice a week significantly suppressed growth of MDA-MB-231 tumors in orthotopic breast cancer models in nude mice with no observed toxicity. In conclusion, our study provides a highly potent and in vivo effective novel small-molecule eEF-2K inhibitor that may be used as a molecularly targeted therapy breast cancer or other eEF-2K-dependent tumors.
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Affiliation(s)
- Ferah Comert Onder
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 422, Houston, Texas 77030, United States.,Department of Medical Biology, Çanakkale Onsekiz Mart University, Faculty of Medicine, 17020 Canakkale, Turkey.,Department of Chemistry, Natural Products and Drug Research Laboratory, Faculty of Science and Arts, Çanakkale Onsekiz Mart University, 17020 Canakkale, Turkey
| | - Nermin Kahraman
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 422, Houston, Texas 77030, United States
| | | | - Ali Cagir
- Izmir Institute of Technology, Department of Chemistry, Bioorganic and Medicinal Chemistry Laboratory, 35430 Urla, Turkey
| | - Hakan Kandemir
- Tekirdag Namik Kemal University, Department of Chemistry, 59030 Tekirdag, Turkey
| | - Gizem Tatar
- Gaziantep University, Institute of Health Sciences, Department of Bioinformatics and Computational Biology, 27310 Gaziantep, Turkey
| | - Tugba Taskin Tok
- Gaziantep University, Institute of Health Sciences, Department of Bioinformatics and Computational Biology, 27310 Gaziantep, Turkey.,Gaziantep University, Faculty of Arts and Sciences, Department of Chemistry, 27310 Gaziantep, Turkey
| | - Goknur Kara
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 422, Houston, Texas 77030, United States
| | | | - Serdar Durdagi
- Department of Biophysics, School of Medicine, Computational Biology and Molecular Simulations Laboratory, Bahcesehir University, 34734 Istanbul, Turkey
| | - Mehmet Ay
- Department of Chemistry, Natural Products and Drug Research Laboratory, Faculty of Science and Arts, Çanakkale Onsekiz Mart University, 17020 Canakkale, Turkey
| | - Bulent Ozpolat
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 422, Houston, Texas 77030, United States.,Center for RNA Interference and Non-Coding RNAs, The University of Texas, MD Anderson Cancer Center, Houston, Texas 77030, United States
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6
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Mendes A, Gigan JP, Rodriguez Rodrigues C, Choteau SA, Sanseau D, Barros D, Almeida C, Camosseto V, Chasson L, Paton AW, Paton JC, Argüello RJ, Lennon-Duménil AM, Gatti E, Pierre P. Proteostasis in dendritic cells is controlled by the PERK signaling axis independently of ATF4. Life Sci Alliance 2020; 4:4/2/e202000865. [PMID: 33443099 PMCID: PMC7756897 DOI: 10.26508/lsa.202000865] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/10/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022] Open
Abstract
Differentiated dendritic cells display an unusual activation of the integrated stress response, which is necessary for normal type-I Interferon production and cell migration. In stressed cells, phosphorylation of eukaryotic initiation factor 2α (eIF2α) controls transcriptome-wide changes in mRNA translation and gene expression known as the integrated stress response. We show here that DCs are characterized by high eIF2α phosphorylation, mostly caused by the activation of the ER kinase PERK (EIF2AK3). Despite high p-eIF2α levels, DCs display active protein synthesis and no signs of a chronic integrated stress response. This biochemical specificity prevents translation arrest and expression of the transcription factor ATF4 during ER-stress induction by the subtilase cytotoxin (SubAB). PERK inactivation, increases globally protein synthesis levels and regulates IFN-β expression, while impairing LPS-stimulated DC migration. Although the loss of PERK activity does not impact DC development, the cross talk existing between actin cytoskeleton dynamics; PERK and eIF2α phosphorylation is likely important to adapt DC homeostasis to the variations imposed by the immune contexts.
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Affiliation(s)
- Andreia Mendes
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Julien P Gigan
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Christian Rodriguez Rodrigues
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Sébastien A Choteau
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Aix-Marseille Université, INSERM, Theories and Approaches of Genomic Complexity (TAGC), CENTURI, Marseille, France
| | - Doriane Sanseau
- INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Daniela Barros
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Catarina Almeida
- Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Voahirana Camosseto
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Lionel Chasson
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Adrienne W Paton
- Department of Molecular and Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - James C Paton
- Department of Molecular and Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - Rafael J Argüello
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | | | - Evelina Gatti
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France .,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Philippe Pierre
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France .,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
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7
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Integrated transcriptome and phosphoproteome analyses reveal that fads2 is critical for maintaining body LC-PUFA homeostasis. J Proteomics 2020; 229:103967. [PMID: 32891890 DOI: 10.1016/j.jprot.2020.103967] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 08/04/2020] [Accepted: 08/31/2020] [Indexed: 11/21/2022]
Abstract
Fatty acid desaturate 2 (Fads2) is associated with many chronic diseases. Nevertheless, comprehensive researches on its role have not been performed. We here conducted an integrated analysis of long-chain polyunsaturated fatty acid (LC-PUFA) metabolism of fads2-deletion zebrafish (fads2-/-) by transcriptomics, proteomics and phosphoproteomics. Compared with wild type zebrafish (WT), fads2-/- showed significantly higher contents of hepatic linoleic acid (all-cis-9,12-C18:2), α-linolenic acid (all-cis-9,12,15-C18:3) and docosapetaenoic acid (all-cis-7,10,13,16,19-C22:5), and lower contents of γ-linolenic acid (all-cis-6,9,12-C18:3), stearidonic acid (all-cis-6,9,12,15-C18:4) and docosahexaenoic acid (all-cis-4,7,10,13,16,19-C22:6), accompanied by an increased n-6/n-3 PUFA level. In total, we identified 1608 differentially expressed genes (DEGs), 209 differentially expressed proteins (DEPs) and 153 differentially expressed phosphorylated proteins (DEPPs) with 190 sites between fads2-/- and WT. Transcriptome and proteome analysis simultaneously aggregated these DEGs and DEPs into LC-PUFA synthesis and PPAR signaling pathways. Further interaction network analysis of the DEPPs showed that spliceosome and protein processing in endoplasmic reticulum pathway were critical groups. Additionally, we determined seven highly phosphorylated kinases and a highly expressed phosphatase in fads2-/- zebrafish. These results give insights into the mechanism by which fads2 affects metabolic disease occurrence, and provide datasets for target selections for human disease treatment. SIGNIFICANCE: Balanced LC-PUFA composition was deeply associated with body health, while changes of LC-PUFAs usually induced serious diseases such as cardiovascular disease, type 2 diabetes and inflammatory disease. Fatty acid desaturase 2 (Fads2), subordinating to the fatty acid desaturase protein family, catalyzes the first desaturation reaction in LC-PUFA synthesis. Although Fads2 is associated with many chronic diseases including metabolic abnormalities, type 2 diabetes and obesity, comprehensive researches on its role have not been performed. On the basis of the integrated transcriptome, proteome and phosphoproteome analysis, we identified that fads2 was critical for maintaining body LC-PUFA homeostasis. Moreover, the crucial pathways including PPAR signaling pathway, spliceosome and protein processing in endoplasmic reticulum pathway, and candidate kinase targets associated with LC-PUFA metabolism were determined. These findings will contribute to the revealing of the mechanism and supply possible datasets for target selection for human disease treatment.
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8
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Karakas D, Ozpolat B. Eukaryotic elongation factor-2 kinase (eEF2K) signaling in tumor and microenvironment as a novel molecular target. J Mol Med (Berl) 2020; 98:775-787. [PMID: 32377852 DOI: 10.1007/s00109-020-01917-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 12/25/2022]
Abstract
Eukaryotic elongation factor-2 kinase (eEF2K), an atypical member of alpha-kinase family, is highly overexpressed in breast, pancreatic, brain, and lung cancers, and associated with poor survival in patients. eEF2K promotes cell proliferation, survival, and aggressive tumor characteristics, leading to tumor growth and progression. While initial studies indicated that eEF2K acts as a negative regulator of protein synthesis by suppressing peptide elongation phase, later studies demonstrated that it has multiple functions and promotes cell cycle, angiogenesis, migration, and invasion as well as induction of epithelial-mesenchymal transition through induction of integrin β1, SRC/FAK, PI3K/AKT, cyclin D1, VEGF, ZEB1, Snail, and MMP-2. Under stress conditions such as hypoxia and metabolic distress, eEF2K is activated by several signaling pathways and slows down protein synthesis and helping cells to save energy and survive. In vivo therapeutic targeting of eEF2K by genetic methods inhibits tumor growth in various tumor models, validating it as a potential molecular target. Recent studies suggest that eEF2K plays a role in tumor microenvironment cells by monocyte chemoattractant protein-1 (MCP-1) and accumulation of tumor-associated macrophages. Due to its clinical significance and the pivotal role in tumorigenesis and progression, eEF2K is considered as an important therapeutic target in solid tumors. However, currently, there is no specific and potent inhibitor for translation into clinical studies. Here, we aim to systematically review current knowledge regarding eEF2K in tumor biology, microenvironment, and development of eEF2K targeted inhibitors and therapeutics.
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Affiliation(s)
- Didem Karakas
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Istinye University, Istanbul, Turkey
| | - Bulent Ozpolat
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
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9
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Xiao M, Xie J, Wu Y, Wang G, Qi X, Liu Z, Wang Y, Wang X, Hoque A, Oakhill J, Proud CG, Li J. The eEF2 kinase-induced STAT3 inactivation inhibits lung cancer cell proliferation by phosphorylation of PKM2. Cell Commun Signal 2020; 18:25. [PMID: 32054489 PMCID: PMC7020344 DOI: 10.1186/s12964-020-0528-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 02/05/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Eukaryotic elongation factor-2 kinase (eEF2K) is a Ca 2+ /calmodulin (CaM)-dependent protein kinase that inhibits protein synthesis. However, the role of eEF2K in cancer development was reported paradoxically and remains to be elucidated. METHODS Herein, A549 cells with eEF2K depletion or overexpression by stably transfected lentivirus plasmids were used in vitro and in vivo study. MTT and colony assays were used to detect cell proliferation and growth. Extracellular glucose and lactate concentration were measured using test kit. Immunoblot and co-immunoprecipitation assays were used to examine the molecular biology changes and molecular interaction in these cells. LC-MS/MS analysis and [γ- 32 P] ATP kinase assay were used to identify combining protein and phosphorylation site. Nude mice was utilized to study the correlation of eEF2K and tumor growth in vivo. RESULTS We demonstrated that eEF2K inhibited lung cancer cells proliferation and affected the inhibitory effects of EGFR inhibitor gefitinib. Mechanistically, we showed that eEF2K formed a complex with PKM2 and STAT3, thereby phosphorylated PKM2 at T129, leading to reduced dimerization of PKM2. Subsequently, PKM2 impeded STAT3 phosphorylation and STAT3-dependent c-Myc expression. eEF2K depletion promoted the nuclear translocation of PKM2 and increased aerobic glycolysis reflected by increased lactate secretion and glucose. CONCLUSIONS Our findings define a novel mechanism underlying the regulation of cancer cell proliferation by eEF2K independent of its role in protein synthesis, disclosing the diverse roles of eEF2K in cell biology, which lays foundation for the development of new anticancer therapeutic strategies.
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Affiliation(s)
- Min Xiao
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Jianling Xie
- South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
| | - Yu Wu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Genzhu Wang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Xin Qi
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Zailiang Liu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Yuying Wang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Xuemin Wang
- South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Ashfaqul Hoque
- St Vincent's Institute of Medical Research, Fitzroy, SA, 4312, Australia
| | - Jon Oakhill
- St Vincent's Institute of Medical Research, Fitzroy, SA, 4312, Australia
| | - Christopher G Proud
- South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jing Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, People's Republic of China.
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, People's Republic of China.
- Open Studio for Druggability Research of Marine Natural Products, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, People's Republic of China.
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10
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By reducing global mRNA translation in several ways, 2-deoxyglucose lowers MCL-1 protein and sensitizes hemopoietic tumor cells to BH3 mimetic ABT737. Cell Death Differ 2018; 26:1766-1781. [PMID: 30538285 PMCID: PMC6748140 DOI: 10.1038/s41418-018-0244-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/30/2018] [Accepted: 11/15/2018] [Indexed: 01/15/2023] Open
Abstract
Drugs targeting various pro-survival BCL-2 family members (‘‘BH3 mimetics’’) have efficacy in hemopoietic malignancies, but the non-targeted pro-survival family members can promote resistance. Pertinently, the sensitivity of some tumor cell lines to BH3 mimetic ABT737, which targets BCL-2, BCL-XL, and BCL-W but not MCL-1, is enhanced by 2-deoxyglucose (2DG). We found that 2DG augmented apoptosis induced by ABT737 in 3 of 8 human hemopoietic tumor cell lines, most strongly in pre-B acute lymphocytic leukemia cell line NALM-6, the focus of our mechanistic studies. Although 2DG can lower MCL-1 translation, how it does so is incompletely understood, in part because 2DG inhibits both glycolysis and protein glycosylation in the endoplasmic reticulum (ER). Its glycolysis inhibition lowered ATP and, through the AMPK/mTORC1 pathway, markedly reduced global protein synthesis, as did an ER integrated stress response. A dual reporter assay revealed that 2DG impeded not only cap-dependent translation but also elongation or cap-independent translation. MCL-1 protein fell markedly, whereas 12 other BCL-2 family members were unaffected. We ascribe the MCL-1 drop to the global fall in translation, exacerbated for mRNAs with a structured 5′ untranslated region (5′UTR) containing potential regulatory motifs like those in MCL-1 mRNA and the short half-life of MCL-1 protein. Pertinently, 2DG downregulated two other short-lived oncoproteins, MYC and MDM2. Thus, our results support MCL-1 as a critical 2DG target, but also reveal multiple effects on global translation that may well also affect its promotion of apoptosis.
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11
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Argüello RJ, Reverendo M, Mendes A, Camosseto V, Torres AG, Ribas de Pouplana L, van de Pavert SA, Gatti E, Pierre P. SunRiSE - measuring translation elongation at single-cell resolution by means of flow cytometry. J Cell Sci 2018; 131:jcs.214346. [PMID: 29700204 DOI: 10.1242/jcs.214346] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/04/2018] [Indexed: 12/30/2022] Open
Abstract
The rate at which ribosomes translate mRNAs regulates protein expression by controlling co-translational protein folding and mRNA stability. Many factors regulate translation elongation, including tRNA levels, codon usage and phosphorylation of eukaryotic elongation factor 2 (eEF2). Current methods to measure translation elongation lack single-cell resolution, require expression of multiple transgenes and have never been successfully applied ex vivo Here, we show, by using a combination of puromycilation detection and flow cytometry (a method we call 'SunRiSE'), that translation elongation can be measured accurately in primary cells in pure or heterogenous populations isolated from blood or tissues. This method allows for the simultaneous monitoring of multiple parameters, such as mTOR or S6K1/2 signaling activity, the cell cycle stage and phosphorylation of translation factors in single cells, without elaborated, costly and lengthy purification procedures. We took advantage of SunRiSE to demonstrate that, in mouse embryonic fibroblasts, eEF2 phosphorylation by eEF2 kinase (eEF2K) mostly affects translation engagement, but has a surprisingly small effect on elongation, except after proteotoxic stress induction.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France
| | - Marisa Reverendo
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France
| | - Andreia Mendes
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France
| | - Voahirana Camosseto
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France
| | - Adrian G Torres
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Parc Científic de Barcelona, C/Baldiri Reixac 10, 08028 Barcelona, Catalonia, Spain
| | - Lluis Ribas de Pouplana
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Parc Científic de Barcelona, C/Baldiri Reixac 10, 08028 Barcelona, Catalonia, Spain.,Catalan Institute for Research and Advanced Studies (ICREA), P/Lluis Companys 23, 08010 Barcelona, Catalonia, Spain
| | - Serge A van de Pavert
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France.,Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, 13288, Marseille Cedex 9, France .,Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal
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12
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Will N, Lee K, Hajredini F, Giles DH, Abzalimov RR, Clarkson M, Dalby KN, Ghose R. Structural Dynamics of the Activation of Elongation Factor 2 Kinase by Ca 2+-Calmodulin. J Mol Biol 2018; 430:2802-2821. [PMID: 29800565 DOI: 10.1016/j.jmb.2018.05.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 05/16/2018] [Accepted: 05/16/2018] [Indexed: 11/18/2022]
Abstract
Eukaryotic elongation factor 2 kinase (eEF-2K), the only known calmodulin (CaM)-activated α-kinase, phosphorylates eukaryotic elongation factor 2 (eEF-2) on a specific threonine (Thr-56) diminishing its affinity for the ribosome and reducing the rate of nascent chain elongation during translation. Despite its critical cellular role, the precise mechanisms underlying the CaM-mediated activation of eEF-2K remain poorly defined. Here, employing a minimal eEF-2K construct (TR) that exhibits activity comparable to the wild-type enzyme and is fully activated by CaM in vitro and in cells, and using a variety of complimentary biophysical techniques in combination with computational modeling, we provide a structural mechanism by which CaM activates eEF-2K. Native mass analysis reveals that CaM, with two bound Ca2+ ions, forms a stoichiometric 1:1 complex with TR. Chemical crosslinking mass spectrometry and small-angle X-ray scattering measurements localize CaM near the N-lobe of the TR kinase domain and the spatially proximal C-terminal helical repeat. Hydrogen/deuterium exchange mass spectrometry and methyl NMR indicate that the conformational changes induced on TR by the engagement of CaM are not localized but are transmitted to remote regions that include the catalytic site and the functionally important phosphate binding pocket. The structural insights obtained from the present analyses, together with our previously published kinetics data, suggest that TR, and by inference, wild-type eEF-2K, upon engaging CaM undergoes a conformational transition resulting in a state that is primed to efficiently auto-phosphorylate on the primary activating T348 en route to full activation.
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Affiliation(s)
- Nathan Will
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA
| | - Kwangwoon Lee
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA
| | - Fatlum Hajredini
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA
| | - David H Giles
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, TX 78712, USA
| | - Rinat R Abzalimov
- Biomolecular Mass Spectrometry Facility, CUNY ASRC, New York, NY 10031, USA
| | - Michael Clarkson
- Molecular Structures Core, University of Arizona, Tucson, AZ 85721, USA
| | - Kevin N Dalby
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, TX 78712, USA; Graduate Program in Cell and Molecular Biology, University of Texas, Austin, TX 78712, USA.
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA; Graduate Program in Chemistry, The Graduate Center of CUNY, New York, NY 10016, USA; Graduate Program in Physics, The Graduate Center of CUNY, New York, NY 10016, USA.
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13
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Xie J, Shen K, Lenchine RV, Gethings LA, Trim PJ, Snel MF, Zhou Y, Kenney JW, Kamei M, Kochetkova M, Wang X, Proud CG. Eukaryotic elongation factor 2 kinase upregulates the expression of proteins implicated in cell migration and cancer cell metastasis. Int J Cancer 2017; 142:1865-1877. [PMID: 29235102 DOI: 10.1002/ijc.31210] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 10/23/2017] [Accepted: 12/05/2017] [Indexed: 01/01/2023]
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) negatively regulates the elongation phase of mRNA translation and hence protein synthesis. Increasing evidence indicates that eEF2K plays an important role in the survival and migration of cancer cells and in tumor progression. As demonstrated by two-dimensional wound-healing and three-dimensional transwell invasion assays, knocking down or inhibiting eEF2K in cancer cells impairs migration and invasion of cancer cells. Conversely, exogenous expression of eEF2K or knocking down eEF2 (the substrate of eEF2K) accelerates wound healing and invasion. Importantly, using LC-HDMSE analysis, we identify 150 proteins whose expression is decreased and 73 proteins which are increased upon knocking down eEF2K in human lung carcinoma cells. Of interest, 34 downregulated proteins are integrins and other proteins implicated in cell migration, suggesting that inhibiting eEF2K may help prevent cancer cell mobility and metastasis. Interestingly, eEF2K promotes the association of integrin mRNAs with polysomes, providing a mechanism by which eEF2K may enhance their cellular levels. Consistent with this, genetic knock down or pharmacological inhibition of eEF2K reduces the protein expression levels of integrins. Notably, pharmacological or genetic inhibition of eEF2K almost completely blocked tumor growth and effectively prevented the spread of tumor cells in vivo. High levels of eEF2K expression were associated with invasive carcinoma and metastatic tumors. These data provide the evidence that eEF2K is a new potential therapeutic target for preventing tumor metastasis.
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Affiliation(s)
- Jianling Xie
- Nutrition & Metabolism, South Australian Health & Medical Research Institute, Adelaide, Australia.,Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Kaikai Shen
- School of Basic Medical Sciences, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Roman V Lenchine
- Nutrition & Metabolism, South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Lee A Gethings
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, United Kingdom
| | - Paul J Trim
- Hopwood Centre for Neurobiology, South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Marten F Snel
- Hopwood Centre for Neurobiology, South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Ying Zhou
- School of Basic Medical Sciences, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Justin W Kenney
- Program in Neurosciences and Mental Health, the Hospital for Sick Children, Toronto, Canada
| | - Makoto Kamei
- Hopwood Centre for Neurobiology, South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Marina Kochetkova
- Centre for Cancer Biology, SA Pathology and the University of South Australia, Adelaide, Australia
| | - Xuemin Wang
- Nutrition & Metabolism, South Australian Health & Medical Research Institute, Adelaide, Australia.,Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom.,School of Biological Sciences, University of Adelaide, Adelaide, Australia
| | - Christopher G Proud
- Nutrition & Metabolism, South Australian Health & Medical Research Institute, Adelaide, Australia.,Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom.,Hopwood Centre for Neurobiology, South Australian Health & Medical Research Institute, Adelaide, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, Australia
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14
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Johanns M, Pyr Dit Ruys S, Houddane A, Vertommen D, Herinckx G, Hue L, Proud CG, Rider MH. Direct and indirect activation of eukaryotic elongation factor 2 kinase by AMP-activated protein kinase. Cell Signal 2017; 36:212-221. [PMID: 28502587 DOI: 10.1016/j.cellsig.2017.05.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 04/27/2017] [Accepted: 05/10/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Eukaryotic elongation factor 2 (eEF2) kinase (eEF2K) is a key regulator of protein synthesis in mammalian cells. It phosphorylates and inhibits eEF2, the translation factor necessary for peptide translocation during the elongation phase of protein synthesis. When cellular energy demand outweighs energy supply, AMP-activated protein kinase (AMPK) and eEF2K become activated, leading to eEF2 phosphorylation, which reduces the rate of protein synthesis, a process that consumes a large proportion of cellular energy under optimal conditions. AIM The goal of the present study was to elucidate the mechanisms by which AMPK activation leads to increased eEF2 phosphorylation to decrease protein synthesis. METHODS Using genetically modified mouse embryo fibroblasts (MEFs), effects of treatments with commonly used AMPK activators to increase eEF2 phosphorylation were compared with that of the novel compound 991. Bacterially expressed recombinant eEF2K was phosphorylated in vitro by recombinant activated AMPK for phosphorylation site-identification by mass spectrometry followed by site-directed mutagenesis of the identified sites to alanine residues to study effects on the kinetic properties of eEF2K. Wild-type eEF2K and a Ser491/Ser492 mutant were retrovirally re-introduced in eEF2K-deficient MEFs and effects of 991 treatment on eEF2 phosphorylation and protein synthesis rates were studied in these cells. RESULTS & CONCLUSIONS AMPK activation leads to increased eEF2 phosphorylation in MEFs mainly by direct activation of eEF2K and partly by inhibition of mammalian target of rapamycin complex 1 (mTORC1) signaling. Treatment of MEFs with AMPK activators can also lead to eEF2K activation independently of AMPK probably via a rise in intracellular Ca2+. AMPK activates eEF2K by multi-site phosphorylation and the newly identified Ser491/Ser492 is important for activation, leading to mTOR-independent inhibition of protein synthesis. Our study provides new insights into the control of eEF2K by AMPK, with implications for linking metabolic stress to decreased protein synthesis to conserve energy reserves, a pathway that is of major importance in cancer cell survival.
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Affiliation(s)
- M Johanns
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - S Pyr Dit Ruys
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - A Houddane
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - D Vertommen
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - G Herinckx
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - L Hue
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium
| | - C G Proud
- South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide, North Terrace, Adelaide, SA 5000, Australia
| | - M H Rider
- Université catholique de Louvain (UCL), de Duve Institute, Avenue Hippocrate 75 bte 74.02, 1200-Brussels, Belgium.
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