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Zhang H, Cai J, Yu S, Sun B, Zhang W. Anticancer Small-Molecule Agents Targeting Eukaryotic Elongation Factor 1A: State of the Art. Int J Mol Sci 2023; 24:ijms24065184. [PMID: 36982256 PMCID: PMC10049629 DOI: 10.3390/ijms24065184] [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: 02/16/2023] [Revised: 03/05/2023] [Accepted: 03/07/2023] [Indexed: 03/29/2023] Open
Abstract
Eukaryotic elongation factor 1A (eEF1A) canonically delivers amino acyl tRNA to the ribosomal A site during the elongation stage of protein biosynthesis. Yet paradoxically, the oncogenic nature of this instrumental protein has long been recognized. Consistently, eEF1A has proven to be targeted by a wide assortment of small molecules with excellent anticancer activity, among which plitidepsin has been granted approval for the treatment of multiple myeloma. Meanwhile, metarrestin is currently under clinical development for metastatic cancers. Bearing these exciting advances in mind, it would be desirable to present a systematic up-to-date account of the title topic, which, to the best of our knowledge, has thus far been unavailable in the literature. The present review summarizes recent advances in eEF1A-targeting anticancer agents, both naturally occurring and synthetically crafted, with regard to their discovery or design, target identification, structure–activity relationship, and mode of action. Their structural diversity and differential eEF1A-targeting mechanisms warrant continuing research in pursuit of curing eEF1A-driven malignancy.
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Zhang H, Tian Y, Yuan X, Xie F, Yu S, Cai J, Sun B, Shan C, Zhang W. Site-directed late-stage diversification of macrocyclic nannocystins facilitating anticancer SAR and mode of action studies. RSC Med Chem 2023; 14:299-312. [PMID: 36846368 PMCID: PMC9945860 DOI: 10.1039/d2md00393g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Nannocystins are a family of 21-membered cyclodepsipeptides with excellent anticancer activity. However, their macrocyclic architecture poses a significant challenge to structure modification. Herein, this issue is addressed by leveraging the strategy of post-macrocyclization diversification. In particular, a novel serine-incorporating nannocystin was designed so that its appending hydroxyl group could diversify into a wide variety of side chain analogues. Such effort facilitated not only structure-activity correlation at the subdomain of interest, but also the development of a macrocyclic coumarin-labeled fluorescence probe. Uptake experiments indicated good cell permeability of the probe, and endoplasmic reticulum was identified as its subcellular localization site.
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Affiliation(s)
- Han Zhang
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Yunfeng Tian
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Xiaoya Yuan
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Fei Xie
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Siqi Yu
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Jiayou Cai
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Bin Sun
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Changliang Shan
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
| | - Weicheng Zhang
- The State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University Tianjin People's Republic of China
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Kachaev ZM, Ivashchenko SD, Kozlov EN, Lebedeva LA, Shidlovskii YV. Localization and Functional Roles of Components of the Translation Apparatus in the Eukaryotic Cell Nucleus. Cells 2021; 10:3239. [PMID: 34831461 PMCID: PMC8623629 DOI: 10.3390/cells10113239] [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: 09/28/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/15/2022] Open
Abstract
Components of the translation apparatus, including ribosomal proteins, have been found in cell nuclei in various organisms. Components of the translation apparatus are involved in various nuclear processes, particularly those associated with genome integrity control and the nuclear stages of gene expression, such as transcription, mRNA processing, and mRNA export. Components of the translation apparatus control intranuclear trafficking; the nuclear import and export of RNA and proteins; and regulate the activity, stability, and functional recruitment of nuclear proteins. The nuclear translocation of these components is often involved in the cell response to stimulation and stress, in addition to playing critical roles in oncogenesis and viral infection. Many components of the translation apparatus are moonlighting proteins, involved in integral cell stress response and coupling of gene expression subprocesses. Thus, this phenomenon represents a significant interest for both basic and applied molecular biology. Here, we provide an overview of the current data regarding the molecular functions of translation factors and ribosomal proteins in the cell nucleus.
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Affiliation(s)
- Zaur M. Kachaev
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
- Center for Genetics and Life Science, Sirius University of Science and Technology, 354340 Sochi, Russia
| | - Sergey D. Ivashchenko
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Eugene N. Kozlov
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Lyubov A. Lebedeva
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Yulii V. Shidlovskii
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
- Center for Genetics and Life Science, Sirius University of Science and Technology, 354340 Sochi, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), 119992 Moscow, Russia
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4
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Gong T, Shuang Y. Expression and Clinical Value of Eukaryotic Translation Elongation Factor 1A1 (EEF1A1) in Diffuse Large B Cell Lymphoma. Int J Gen Med 2021; 14:7247-7258. [PMID: 34737619 PMCID: PMC8559353 DOI: 10.2147/ijgm.s324645] [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: 06/21/2021] [Accepted: 07/29/2021] [Indexed: 12/02/2022] Open
Abstract
Background The eukaryotic translation elongation factor 1A1 (EEF1A1) participates in protein translation and has been reported to be involved in tumor progression such as hepatocellular carcinoma. Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy in adults. In the present study, we aimed to detect the expression of EEF1A1 in DLBCL and to analyze its relationship with prognosis. Methods We reviewed medical records of DLBCL patients in our hospital and evaluated their expression level of EEF1A1 in tumor tissues using immunohistochemical (IHC) assay. The Chi-square method was used for correlation analysis. The Kaplan–Meier method with Log rank test was used for univariate analysis. Cox proportional hazards model was used for multivariate analysis. Cellular and mice models were introduced to validate its oncogenic role. Results EEF1A1 expression in tumor cells was higher in certain DLBCL cases. Patients with higher EEF1A1 expression were more likely to have advanced tumor stage and poorer 5-year overall survival (OS) rates. EEF1A1 expression in tumor cells was an independent risk predictor for OS (P < 0.05). Cellular assays demonstrated that EEF1A1-shRNA significantly inhibited lymphoma cell proliferation. The study of xenografts further verified the effect of EEF1A1-shRNA on suppressing tumor growth in vivo. Conclusion EEF1A1 positivity predicts short survival in DLBCL patients. For patients with higher EEF1A1 expression, more strategy such as anti-EEF1A1 antibody treatment should be developed.
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Affiliation(s)
- Tiejun Gong
- Institute of Hematology and Oncology, Harbin the First Hospital, Harbin, 150010, People's Republic of China
| | - Yuerong Shuang
- Department of Lymphatic Hematology and Oncology, Jiangxi Cancer Hospital, Nanchang, 330029, People's Republic of China
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5
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Bchini R, Girardet JM, Sormani R, Gelhaye E, Morel-Rouhier M. Oxidized glutathione promotes association between eukaryotic translation elongation factor 1Bγ and Ure2p glutathione transferase from Phanerochaete chrysosporium. FEBS J 2020; 288:2956-2969. [PMID: 33124131 DOI: 10.1111/febs.15614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/10/2020] [Accepted: 10/27/2020] [Indexed: 11/27/2022]
Abstract
The eukaryotic translation elongation factor 1Bγ (eEF1Bγ) is an atypical member of the glutathione transferase (GST) superfamily. Contrary to more classical GSTs having a role in toxic compound detoxification, eEF1Bγ is suggested to act as a scaffold protein, anchoring the elongation factor complex EF1B to the endoplasmic reticulum. In this study, we show that eEF1Bγ from the basidiomycete Phanerochaete chrysosporium is fully active as a glutathione transferase in vitro and undergoes conformational changes upon binding of oxidized glutathione. Using real-time analyses of biomolecular interactions, we show that GSSG allows eEF1Bγ to physically interact with other GSTs from the Ure2p class, opening new perspectives for a better understanding of the role of eEF1Bγ in cellular oxidative stress response.
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McLachlan F, Sires AM, Abbott CM. The role of translation elongation factor eEF1 subunits in neurodevelopmental disorders. Hum Mutat 2018; 40:131-141. [PMID: 30370994 DOI: 10.1002/humu.23677] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 10/16/2018] [Accepted: 10/23/2018] [Indexed: 11/06/2022]
Abstract
The multi-subunit eEF1 complex plays a crucial role in de novo protein synthesis. The central functional component of the complex is eEF1A, which occurs as two independently encoded variants with reciprocal expression patterns: whilst eEF1A1 is widely expressed, eEF1A2 is found only in neurons and muscle. Heterozygous mutations in the gene encoding eEF1A2, EEF1A2, have recently been shown to cause epilepsy, autism, and intellectual disability. The remaining subunits of the eEF1 complex, eEF1Bα, eEF1Bδ, eEF1Bγ, and valyl-tRNA synthetase (VARS), together form the GTP exchange factor for eEF1A and are ubiquitously expressed, in keeping with their housekeeping role. However, mutations in the genes encoding these subunits EEF1B2 (eEF1Bα), EEF1D (eEF1Bδ), and VARS (valyl-tRNA synthetase) have also now been identified as causes of neurodevelopmental disorders. In this review, we describe the mutations identified so far in comparison with the degree of normal variation in each gene, and the predicted consequences of the mutations on the functions of the proteins and their isoforms. We discuss the likely effects of the mutations in the context of the role of protein synthesis in neuronal development.
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Affiliation(s)
- Fiona McLachlan
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Anna Martinez Sires
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
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7
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Dalgliesh AJ, Liu ZZ, Griffiths LG. Magnesium Presence Prevents Removal of Antigenic Nuclear-Associated Proteins from Bovine Pericardium for Heart Valve Engineering. Tissue Eng Part A 2017; 23:609-621. [PMID: 28178887 DOI: 10.1089/ten.tea.2016.0405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Current heart valve prostheses are associated with significant complications, including aggressive immune response, limited valve life expectancy, and inability to grow in juvenile patients. Animal derived "tissue" valves undergo glutaraldehyde fixation to mask tissue antigenicity; however, chronic immunological responses and associated calcification still commonly occur. A heart valve formed from an unfixed bovine pericardium (BP) extracellular matrix (ECM) scaffold, in which antigenic burden has been eliminated or significantly reduced, has potential to overcome deficiencies of current bioprostheses. Decellularization and antigen removal methods frequently use sequential solutions extrapolated from analytical chemistry approaches to promote solubility and removal of tissue components from resultant ECM scaffolds. However, the extent to which such prefractionation strategies may inhibit removal of antigenic tissue components has not been explored. We hypothesize that presence of magnesium in prefractionation steps causes DNA precipitation and reduces removal of nuclear-associated antigenic proteins. Keeping all variables consistent bar the addition or absence of magnesium (2 mM magnesium chloride hexahydrate), residual BP ECM scaffold antigenicity and removed antigenicity were assessed, along with residual and removed DNA content, ECM morphology, scaffold composition, and recellularization potential. Furthermore, we used proteomic methods to determine the mechanism by which magnesium presence or absence affects scaffold residual antigenicity. This study demonstrates that absence of magnesium from antigen removal solutions enhances solubility and subsequent removal of antigenic nuclear-associated proteins from BP. We therefore conclude that the primary mechanism of action for magnesium removal during antigen removal processes is avoidance of DNA precipitation, facilitating solubilization and removal of nuclear-associated antigenic proteins. Future studies are necessary to further facilitate solubility and removal of nuclear-associated antigenic proteins from xenogeneic ECM scaffolds, in addition to an in vivo assessing of the material.
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Affiliation(s)
- Ailsa J Dalgliesh
- 1 Department of Veterinary Medicine, Medicine and Epidemiology, University of California , Davis, Davis, California.,2 Department of Cardiovascular Diseases, Mayo Clinic , Rochester, Minnesota
| | - Zhi Zhao Liu
- 1 Department of Veterinary Medicine, Medicine and Epidemiology, University of California , Davis, Davis, California
| | - Leigh G Griffiths
- 1 Department of Veterinary Medicine, Medicine and Epidemiology, University of California , Davis, Davis, California.,2 Department of Cardiovascular Diseases, Mayo Clinic , Rochester, Minnesota
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8
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Palacios G, Shaw TI, Li Y, Singh RK, Valentine M, Sandlund JT, Lim MS, Mullighan CG, Leventaki V. Novel ALK fusion in anaplastic large cell lymphoma involving EEF1G, a subunit of the eukaryotic elongation factor-1 complex. Leukemia 2016; 31:743-747. [PMID: 27840423 DOI: 10.1038/leu.2016.331] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- G Palacios
- Department of Pathology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - T I Shaw
- Department of Computational Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Y Li
- Department of Computational Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - R K Singh
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
| | - M Valentine
- Department of Cytogenetics, St Jude Children's Research Hospital, Memphis, TN, USA
| | - J T Sandlund
- Department of Oncology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - M S Lim
- Department of Pathology, University of Pennsylvania, Philadelphia, PA, USA
| | - C G Mullighan
- Department of Pathology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - V Leventaki
- Department of Pathology, St Jude Children's Research Hospital, Memphis, TN, USA
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9
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Abraham ST. A role for the Wnt3a/β-catenin signaling pathway in the myogenic program of C2C12 cells. In Vitro Cell Dev Biol Anim 2016; 52:935-941. [DOI: 10.1007/s11626-016-0058-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 05/09/2016] [Indexed: 11/27/2022]
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10
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KIM JIHAE, LEE JUNGOK, KIM NAMI, LEE HYEJEONG, LEE YONGWOO, KIM HYUNGIP, KIM SUJIN, PARK SUNHWA, KIM HYEONSOO. Paclitaxel suppresses the viability of breast tumor MCF7 cells through the regulation of EF1α and FOXO3a by AMPK signaling. Int J Oncol 2015; 47:1874-80. [DOI: 10.3892/ijo.2015.3153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 08/13/2015] [Indexed: 11/06/2022] Open
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11
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Bjorlykke Y, Vethe H, Vaudel M, Barsnes H, Berven FS, Tjora E, Raeder H. Carboxyl-Ester Lipase Maturity-Onset Diabetes of the Young Disease Protein Biomarkers in Secretin-Stimulated Duodenal Juice. J Proteome Res 2014; 14:521-30. [DOI: 10.1021/pr500750z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Yngvild Bjorlykke
- KG
Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Jonas Lies Vei 65, Bergen 5021, Norway
- Department
of Pediatrics, Haukeland University Hospital, Jonas Lies vei 65, Bergen 5021, Norway
| | - Heidrun Vethe
- KG
Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Jonas Lies Vei 65, Bergen 5021, Norway
- Department
of Pediatrics, Haukeland University Hospital, Jonas Lies vei 65, Bergen 5021, Norway
| | - Marc Vaudel
- Proteomics
Unit (PROBE), Department of Biomedicine, University of Bergen, Jonas Lies vei 91, Bergen 5009, Norway
| | - Harald Barsnes
- Proteomics
Unit (PROBE), Department of Biomedicine, University of Bergen, Jonas Lies vei 91, Bergen 5009, Norway
| | - Frode S. Berven
- Proteomics
Unit (PROBE), Department of Biomedicine, University of Bergen, Jonas Lies vei 91, Bergen 5009, Norway
| | - Erling Tjora
- Department
of Pediatrics, Haukeland University Hospital, Jonas Lies vei 65, Bergen 5021, Norway
| | - Helge Raeder
- KG
Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Jonas Lies Vei 65, Bergen 5021, Norway
- Department
of Pediatrics, Haukeland University Hospital, Jonas Lies vei 65, Bergen 5021, Norway
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12
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Crepin T, Shalak VF, Yaremchuk AD, Vlasenko DO, McCarthy A, Negrutskii BS, Tukalo MA, El'skaya AV. Mammalian translation elongation factor eEF1A2: X-ray structure and new features of GDP/GTP exchange mechanism in higher eukaryotes. Nucleic Acids Res 2014; 42:12939-48. [PMID: 25326326 PMCID: PMC4227793 DOI: 10.1093/nar/gku974] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Eukaryotic elongation factor eEF1A transits between the GTP- and GDP-bound conformations during the ribosomal polypeptide chain elongation. eEF1A*GTP establishes a complex with the aminoacyl-tRNA in the A site of the 80S ribosome. Correct codon–anticodon recognition triggers GTP hydrolysis, with subsequent dissociation of eEF1A*GDP from the ribosome. The structures of both the ‘GTP’- and ‘GDP’-bound conformations of eEF1A are unknown. Thus, the eEF1A-related ribosomal mechanisms were anticipated only by analogy with the bacterial homolog EF-Tu. Here, we report the first crystal structure of the mammalian eEF1A2*GDP complex which indicates major differences in the organization of the nucleotide-binding domain and intramolecular movements of eEF1A compared to EF-Tu. Our results explain the nucleotide exchange mechanism in the mammalian eEF1A and suggest that the first step of eEF1A*GDP dissociation from the 80S ribosome is the rotation of the nucleotide-binding domain observed after GTP hydrolysis.
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Affiliation(s)
- Thibaut Crepin
- University of Grenoble Alpes, UVHCI, F-38000 Grenoble, France CNRS, UVHCI, F-38000 Grenoble, France Unit for Virus Host-Cell Interactions, University of Grenoble Alpes-EMBL-CNRS, 71 avenue des Martyrs, 38042 France
| | - Vyacheslav F Shalak
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine
| | - Anna D Yaremchuk
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine European Molecular Biology Laboratory, Grenoble Outstation, 71 avenue des Martyrs, 38042 France
| | - Dmytro O Vlasenko
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine
| | - Andrew McCarthy
- Unit for Virus Host-Cell Interactions, University of Grenoble Alpes-EMBL-CNRS, 71 avenue des Martyrs, 38042 France European Molecular Biology Laboratory, Grenoble Outstation, 71 avenue des Martyrs, 38042 France
| | - Boris S Negrutskii
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine
| | - Michail A Tukalo
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine
| | - Anna V El'skaya
- State Key laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, 150 Zabolotnogo str., Kiev 03680, Ukraine
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13
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Achilonu I, Siganunu TP, Dirr HW. Purification and characterisation of recombinant human eukaryotic elongation factor 1 gamma. Protein Expr Purif 2014; 99:70-7. [DOI: 10.1016/j.pep.2014.04.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 04/02/2014] [Accepted: 04/03/2014] [Indexed: 11/17/2022]
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14
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Mingot JM, Vega S, Cano A, Portillo F, Nieto MA. eEF1A mediates the nuclear export of SNAG-containing proteins via the Exportin5-aminoacyl-tRNA complex. Cell Rep 2013; 5:727-37. [PMID: 24209753 DOI: 10.1016/j.celrep.2013.09.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 08/28/2013] [Accepted: 09/23/2013] [Indexed: 11/16/2022] Open
Abstract
Exportin5 mediates the nuclear export of double-stranded RNAs, including pre-microRNAs, adenoviral RNAs, and tRNAs. When tRNAs are aminoacylated, the Exportin5-aminoacyl (aa)-tRNA complex recruits and coexports the translation elongation factor eEF1A. Here, we show that eEF1A binds to Snail transcription factors when bound to their main target, the E-cadherin promoter, facilitating their export to the cytoplasm in association with the aa-tRNA-Exportin5 complex. Snail binds to eEF1A through the SNAG domain, a protein nuclear export signal present in several transcription factor families, and this binding is regulated by phosphorylation. Thus, we describe a nuclear role for eEF1A and provide a mechanism for protein nuclear export that attenuates the activity of SNAG-containing transcription factors.
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MESH Headings
- Active Transport, Cell Nucleus
- Amino Acid Sequence
- Cadherins/genetics
- Cadherins/metabolism
- Cell Nucleus/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- HeLa Cells
- Humans
- Karyopherins/genetics
- Karyopherins/metabolism
- MCF-7 Cells
- Peptide Elongation Factor 1/genetics
- Peptide Elongation Factor 1/metabolism
- Promoter Regions, Genetic
- Protein Structure, Tertiary
- RNA, Transfer, Amino Acyl/genetics
- RNA, Transfer, Amino Acyl/metabolism
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Snail Family Transcription Factors
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcription, Genetic
- Transfection
- Exportin 1 Protein
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Affiliation(s)
- José Manuel Mingot
- Instituto de Neurociencias, CSIC-UMH, Avda. Ramón y Cajal s/n, 03550 San Juan de Alicante, Spain.
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15
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Sasikumar AN, Perez WB, Kinzy TG. The many roles of the eukaryotic elongation factor 1 complex. WILEY INTERDISCIPLINARY REVIEWS-RNA 2012; 3:543-55. [PMID: 22555874 DOI: 10.1002/wrna.1118] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The vast majority of proteins are believed to have one specific function. Throughout the course of evolution, however, some proteins have acquired additional functions to meet the demands of a complex cellular milieu. In some cases, changes in RNA or protein processing allow the cell to make the most of what is already encoded in the genome to produce slightly different forms. The eukaryotic elongation factor 1 (eEF1) complex subunits, however, have acquired such moonlighting functions without alternative forms. In this article, we discuss the canonical functions of the components of the eEF1 complex in translation elongation as well as the secondary interactions they have with other cellular factors outside of the translational apparatus. The eEF1 complex itself changes in composition as the complexity of eukaryotic organisms increases. Members of the complex are also subject to phosphorylation, a potential modulator of both canonical and non-canonical functions. Although alternative functions of the eEF1A subunit have been widely reported, recent studies are shedding light on additional functions of the eEF1B subunits. A thorough understanding of these alternate functions of eEF1 is essential for appreciating their biological relevance.
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Affiliation(s)
- Arjun N Sasikumar
- Department of Molecular Genetics, Microbiology and Immunology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ, USA
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16
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Sivan G, Aviner R, Elroy-Stein O. Mitotic modulation of translation elongation factor 1 leads to hindered tRNA delivery to ribosomes. J Biol Chem 2011; 286:27927-35. [PMID: 21665947 PMCID: PMC3151038 DOI: 10.1074/jbc.m111.255810] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 06/06/2011] [Indexed: 01/31/2023] Open
Abstract
Translation elongation in eukaryotes is mediated by the concerted actions of elongation factor 1A (eEF1A), which delivers aminoacylated tRNA to the ribosome; elongation factor 1B (eEF1B) complex, which catalyzes the exchange of GDP to GTP on eEF1A; and eEF2, which facilitates ribosomal translocation. Here we present evidence in support of a novel mode of translation regulation by hindered tRNA delivery during mitosis. A conserved consensus phosphorylation site for the mitotic cyclin-dependent kinase 1 on the catalytic delta subunit of eEF1B (termed eEF1D) is required for its posttranslational modification during mitosis, resulting in lower affinity to its substrate eEF1A. This modification is correlated with reduced availability of eEF1A·tRNA complexes, as well as reduced delivery of tRNA to and association of eEF1A with elongating ribosomes. This mode of regulation by hindered tRNA delivery, although first discovered in mitosis, may represent a more globally applicable mechanism employed under other physiological conditions that involve down-regulation of protein synthesis at the elongation level.
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Affiliation(s)
- Gilad Sivan
- From the Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ranen Aviner
- From the Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Orna Elroy-Stein
- From the Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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Newbery HJ, Stancheva I, Zimmerman LB, Abbott CM. Evolutionary importance of translation elongation factor eEF1A variant switching: eEF1A1 down-regulation in muscle is conserved in Xenopus but is controlled at a post-transcriptional level. Biochem Biophys Res Commun 2011; 411:19-24. [DOI: 10.1016/j.bbrc.2011.06.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 06/08/2011] [Indexed: 11/15/2022]
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18
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Veremieva M, Khoruzhenko A, Zaicev S, Negrutskii B, El'skaya A. Unbalanced expression of the translation complex eEF1 subunits in human cardioesophageal carcinoma. Eur J Clin Invest 2011; 41:269-76. [PMID: 20964681 DOI: 10.1111/j.1365-2362.2010.02404.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The signalling role of individual subunits released from some stable translation multi-molecular complexes under unfavourable circumstances is known. The disease-related role of the translation elongation factor 1 complex (eEF1) as a whole is never researched; however, its subunits possess apparent regulatory potency. Whether the individual eEF1 subunits can exist and function in cell beyond the complex is not known. MATERIALS AND METHODS The protein and mRNA levels of the A1, Bα, Bβ or Bγ subunits of eEF1 were analysed by Western and Northern blot techniques in the same specimens of cardioesophageal carcinoma and correspondingly paired normal tissues. Cancer-induced changes in localization patterns of the eEF1 subunits were examined immunohistochemically. RESULTS Changes in different eEF1 subunits expression were found to be unbalanced, indicating cancer-related emergence of individual components of the eEF1 complex. Independent overexpression of at least one eEF1 component was observed in 72% clinical samples. Noncomplexed eEF1B subunits were also detected by immunohistochemical analysis. In the normal tissue, localization of the Bα, Bβ and Bγ subunits was nuclear-cytoplasmic while in the cancer tissue the only Bγ subunit stayed in nucleus. CONCLUSIONS Our data are first to indicate that the individual subunits can exist separately from the eEF1B complex in cancer tissues and that disintegration of eEF1B could be an important sign of cancer development. Nuclear localization of Bγ both in normal and in cancer tissues suggests its previously unknown nucleus-specific role in human cells.
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Affiliation(s)
- Marina Veremieva
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kiev, Ukraine
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19
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Zhang X, Tee YH, Heng JK, Zhu Y, Hu X, Margadant F, Ballestrem C, Bershadsky A, Griffiths G, Yu H. Kinectin-mediated endoplasmic reticulum dynamics supports focal adhesion growth in the cellular lamella. J Cell Sci 2010; 123:3901-12. [PMID: 20980389 DOI: 10.1242/jcs.069153] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Focal adhesions (FAs) control cell shape and motility, which are important processes that underlie a wide range of physiological functions. FA dynamics is regulated by cytoskeleton, motor proteins and small GTPases. Kinectin is an integral endoplasmic reticulum (ER) membrane protein that extends the ER along microtubules. Here, we investigated the influence of the ER on FA dynamics within the cellular lamella by disrupting the kinectin-kinesin interaction by overexpressing the minimal kinectin-kinesin interaction domain on kinectin in cells. This perturbation resulted in a morphological change to a rounded cell shape and reduced cell spreading and migration. Immunofluorescence and live-cell imaging demonstrated a kinectin-dependent ER extension into the cellular lamella and ER colocalisation with FAs within the cellular lamella. FRAP experiments showed that ER contact with FAs was accompanied with an increase in FA protein recruitment to FAs. Disruption of the kinectin-kinesin interaction caused a reduction in FA protein recruitment to FAs. This suggests that the ER supports FA growth within the cellular lamella. Microtubule targeting to FAs is known to promote adhesion disassembly; however, ER contact increased FA size even in the presence of microtubules. Our results suggest a scenario whereby kinectin-kinesin interaction facilitates ER transport along microtubules to support FA growth.
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Affiliation(s)
- Xin Zhang
- Graduate Program in Bioengineering, NUS Graduate School for Integrative Sciences and Engineering, 28 Medical Drive, 117456, Singapore
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20
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George J, Prasad S, Mahmood Z, Shukla Y. Studies on glyphosate-induced carcinogenicity in mouse skin: a proteomic approach. J Proteomics 2010; 73:951-64. [PMID: 20045496 DOI: 10.1016/j.jprot.2009.12.008] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 12/14/2009] [Accepted: 12/15/2009] [Indexed: 11/17/2022]
Abstract
Glyphosate is a widely used broad spectrum herbicide, reported to induce various toxic effects in non-target species, but its carcinogenic potential is still unknown. Here we showed the carcinogenic effects of glyphosate using 2-stage mouse skin carcinogenesis model and proteomic analysis. Carcinogenicity study revealed that glyphosate has tumor promoting activity. Proteomic analysis using 2-dimensional gel electrophoresis and mass spectrometry showed that 22 spots were differentially expressed (>2 fold) on glyphosate, 7, 12-dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) application over untreated control. Among them, 9 proteins (translation elongation factor eEF-1 alpha chain, carbonic anhydrase III, annexin II, calcyclin, fab fragment anti-VEGF antibody, peroxiredoxin-2, superoxide dismutase [Cu-Zn], stefin A3, and calgranulin-B) were common and showed similar expression pattern in glyphosate and TPA-treated mouse skin. These proteins are known to be involved in several key processes like apoptosis and growth-inhibition, anti-oxidant responses, etc. The up-regulation of calcyclin, calgranulin-B and down-regulation of superoxide dismutase [Cu-Zn] was further confirmed by immunoblotting, indicating that these proteins can be good candidate biomarkers for skin carcinogenesis induced by glyphosate. Altogether, these results suggested that glyphosate has tumor promoting potential in skin carcinogenesis and its mechanism seems to be similar to TPA.
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Affiliation(s)
- Jasmine George
- Proteomics Laboratory, Indian Institute of Toxicology Research (CSIR), Mahatma Gandhi Marg, Lucknow 226001 UP, India
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21
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Huang B, Liao CL, Lin YP, Chen SC, Wang DL. S-nitrosoproteome in endothelial cells revealed by a modified biotin switch approach coupled with Western blot-based two-dimensional gel electrophoresis. J Proteome Res 2010; 8:4835-43. [PMID: 19673540 DOI: 10.1021/pr9005662] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
NO-mediated S-nitrosation of cysteine residues has been recognized as a fundamental post-translational modification. S-Nitrosation of endothelial cell (EC) proteins can alter function and affect vascular homeostasis. Trace amounts of S-nitrosoproteins in endothelial cells (ECs) in vivo coupled with lability of the S-nitroso bond have hindered a comprehensive characterization. We demonstrate a convenient and reliable method, requiring minimal sample, for the screening and identification of S-nitrosoproteins. ECs treated with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) were subjected to the biotin switch method of labeling, then detected by analytical Western blot-based two-dimensional gel electrophoresis (2-DE). More than 89 SNAP-increased S-nitrosoproteins were detected and 28 of these were successfully excised from preparative 2-DE gel and identified by LC-MS/MS. Moreover, the nitrosocysteine residue for each protein (HSPA9/368, beta-actin/16, TMP3/170, vimentin/328) was also determined, and the relative ratio of S-nitrosation/non-S-nitrosation for Cys328 of vimentin was estimated using MASIC software. By the combination of the biotin switch method with 2-DE and Western blot analysis, S-nitrosoproteins can be screened and characterized by MS, providing a basis for further study of the physiological significance of each S-nitrosoproteins.
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Affiliation(s)
- Bin Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
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22
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Abstract
Cleavage furrows (CFs) have been isolated from dividing sea urchin eggs and the protein constituents have been analyzed by two-dimensional gel electrophoresis (Fujimoto & Mabuchi, J. Biochem. 122, 518-524, 1997). Two proteins of 51 and 32 kDa, respectively, have been found to be enriched in the CF preparation. Here, we show that these proteins are identical to the protein elongation factor 1alpha (EF-1alpha) and 1beta (EF-1beta), respectively. Furthermore, the CF 51-kDa protein is identical to the 51-kDa protein which had been isolated as a component of the microtubule organizing granules of mitotic sea urchin eggs. The 51-kDa protein bundles F-actin in vitro. This activity is suppressed by Ca(2+)/calmodulin or GTPgammaS. The 32-kDa protein binds EF-1alpha both in vitro and in cell extract, and is shown to suppress the F-actin-bundling activity of the 51-kDa protein. Microinjection of a monoclonal antibody against the 51-kDa protein or that of His-tagged 32-kDa protein into dividing sea urchin eggs at the onset of cleavage leads to failure of cytokinesis. These results strongly suggest that EF-1alpha is involved in maintenance of the structure of the contractile ring and EF-1beta regulates the F-actin-bundling activity of EF-1alpha.
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Affiliation(s)
- Hirotaka Fujimoto
- Department of Cell Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
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23
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Baan B, van der Zon GCM, Maassen JA, Ouwens DM. The nuclear appearance of ERK1/2 and p38 determines the sequential induction of ATF2-Thr71 and ATF2-Thr69 phosphorylation by serum in JNK-deficient cells. Mol Cell Endocrinol 2009; 311:94-100. [PMID: 19647037 DOI: 10.1016/j.mce.2009.07.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Revised: 07/15/2009] [Accepted: 07/22/2009] [Indexed: 10/20/2022]
Abstract
Growth factors activate ATF2 via sequential phosphorylation of Thr69 and Thr71, where the ATF2-Thr71-phosphorylation precedes the induction of ATF2-Thr69+71-phosphorylation. Here, we studied the mechanisms contributing to serum-induced two-step ATF2-phosphorylation in JNK1,2-deficient embryonic fibroblasts. Using anion exchange chromatography, ERK1/2 and p38 were identified as ATF2-kinases in vitro. Inhibitor studies as well as nuclear localization experiments show that the sequential nuclear appearance of ERK1/2 and p38 determines the induction of ATF2-Thr71 and ATF2-Thr69+71-phosphorylation in response to serum.
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Affiliation(s)
- Bart Baan
- Department of Molecular Cell Biology, Section Signal Transduction and Ageing, Leiden University Medical Centre, Postzone S1-P, PO Box 9600, 2300 RC Leiden, The Netherlands
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24
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Kaminska M, Havrylenko S, Decottignies P, Le Maréchal P, Negrutskii B, Mirande M. Dynamic Organization of Aminoacyl-tRNA Synthetase Complexes in the Cytoplasm of Human Cells. J Biol Chem 2009; 284:13746-13754. [PMID: 19289464 DOI: 10.1074/jbc.m900480200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The localization in space and in time of proteins within the cytoplasm of eukaryotic cells is a central question of the cellular compartmentalization of metabolic pathways. The assembly of proteins within stable or transient complexes plays an essential role in this process. Here, we examined the subcellular localization of the multi-aminoacyl-tRNA synthetase complex in human cells. The sequestration of its components within the cytoplasm rests on the presence of the eukaryotic-specific polypeptide extensions that characterize the human enzymes, as compared with their prokaryotic counterparts. The cellular mobility of several synthetases, assessed by measuring fluorescence recovery after photobleaching, suggested that they are not freely diffusible within the cytoplasm. Several of these enzymes, isolated by tandem affinity purification, were copurified with ribosomal proteins and actin. The capacity of aminoacyl-tRNA synthetases to interact with polyribosomes and with the actin cytoskeleton impacts their subcellular localization and mobility. Our observations have conceptual implications for understanding how translation machinery is organized in vivo.
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Affiliation(s)
- Monika Kaminska
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
| | - Svitlana Havrylenko
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France; Institute of Molecular Biology and Genetics, 150 Academy Zabolotnogo Street, 03143 Kiev, Ukraine
| | - Paulette Decottignies
- Institut de Biochimie et Biophysique Moléculaire et Cellulaire, UMR 8619 CNRS, Université Paris-Sud, 91405 Orsay, France
| | - Pierre Le Maréchal
- Institut de Biochimie et Biophysique Moléculaire et Cellulaire, UMR 8619 CNRS, Université Paris-Sud, 91405 Orsay, France
| | - Boris Negrutskii
- Institute of Molecular Biology and Genetics, 150 Academy Zabolotnogo Street, 03143 Kiev, Ukraine
| | - Marc Mirande
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France.
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25
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Chen SC, Huang B, Liu YC, Shyu KG, Lin PY, Wang DL. Acute hypoxia enhances proteins' S-nitrosylation in endothelial cells. Biochem Biophys Res Commun 2008; 377:1274-8. [PMID: 18992711 DOI: 10.1016/j.bbrc.2008.10.144] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Accepted: 10/29/2008] [Indexed: 10/21/2022]
Abstract
Hypoxia-induced responses are frequently encountered during cardiovascular injuries. Hypoxia triggers intracellular reactive oxygen species/nitric oxide (NO) imbalance. Recent studies indicate that NO-mediated S-nitrosylation (S-NO) of cysteine residue is a key posttranslational modification of proteins. We demonstrated that acute hypoxia to endothelial cells (ECs) transiently increased the NO levels via endothelial NO synthase (eNOS) activation. A modified biotin-switch method coupled with Western blot on 2-dimensional electrophoresis (2-DE) demonstrated that at least 11 major proteins have significant increase in S-NO after acute hypoxia. Mass analysis by CapLC/Q-TOF identified those as Ras-GTPase-activating protein, protein disulfide-isomerase, human elongation factor-1-delta, tyrosine 3/tryptophan 5-monooxygenase activating protein, and several cytoskeleton proteins. The S-nitrosylated cysteine residue on tropomyosin (Cys 170) and beta-actin (Cys 285) was further verified with the trypsic peptides analyzed by MASCOT search program. Further understanding of the functional relevance of these S-nitrosylated proteins may provide a molecular basis for treating ischemia-induced vascular disorders.
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Affiliation(s)
- Shih Chung Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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26
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Jiang P, Sangild PT, Sit WH, Ngai HHY, Xu R, Siggers JLA, Wan JMF. Temporal Proteomic Analysis of Intestine Developing Necrotizing Enterocolitis following Enteral Formula Feeding to Preterm Pigs. J Proteome Res 2008; 8:72-81. [DOI: 10.1021/pr800638w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pingping Jiang
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Per T. Sangild
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Wai-Hung Sit
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Heidi Hoi-Yee Ngai
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Ruojun Xu
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Jayda Lee Ann Siggers
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
| | - Jennifer Man-Fan Wan
- Division of Agricultural, Food and Nutritional Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China, Department of Human Nutrition, Faculty of Life Science, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
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27
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Chen YH, Su LH, Huang YC, Wang YT, Kao YY, Sun CH. UPF1, a conserved nonsense-mediated mRNA decay factor, regulates cyst wall protein transcripts in Giardia lamblia. PLoS One 2008; 3:e3609. [PMID: 18974834 PMCID: PMC2572189 DOI: 10.1371/journal.pone.0003609] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 10/15/2008] [Indexed: 12/03/2022] Open
Abstract
The Giardia lamblia cyst wall is required for survival outside the host and infection. Three cyst wall protein (cwp) genes identified to date are highly up-regulated during encystation. However, little is known of the molecular mechanisms governing their gene regulation. Messenger RNAs containing premature stop codons are rapidly degraded by a nonsense-mediated mRNA decay (NMD) system to avoid production of non-functional proteins. In addition to RNA surveillance, NMD also regulates thousands of naturally occurring transcripts through a variety of mechanisms. It is interesting to know the NMD pathway in the primitive eukaryotes. Previously, we have found that the giardial homologue of a conserved NMD factor, UPF1, may be functionally conserved and involved in NMD and in preventing nonsense suppression. In this study, we tested the hypothesis that NMD factors can regulate some naturally occurring transcripts in G. lamblia. We found that overexpression of UPF1 resulted in a significant decrease of the levels of CWP1 and cyst formation and of the endogenous cwp1-3, and myb2 mRNA levels and stability. This indicates that NMD could contribute to the regulation of the cwp1-3 and myb2 transcripts, which are key to G. lamblia differentiation into cyst. Interestingly, we also found that UPF1 may be involved in regulation of eight other endogenous genes, including up-regulation of the translation elongation factor gene, whose product increases translation which is required for NMD. Our results indicate that NMD factor could contribute to the regulation of not only nonsense containing mRNAs, but also mRNAs of the key encystation-induced genes and other endogenous genes in the early-diverging eukaryote, G. lamblia.
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Affiliation(s)
- Yi-Hsiu Chen
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Li-Hsin Su
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Yu-Chang Huang
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Yi-Ting Wang
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Yu-Yun Kao
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Chin-Hung Sun
- Department of Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
- * E-mail:
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28
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Gillen CM, Gao Y, Niehaus-Sauter MM, Wylde MR, Wheatly MG. Elongation factor 1Bgamma (eEF1Bgamma) expression during the molting cycle and cold acclimation in the crayfish Procambarus clarkii. Comp Biochem Physiol B Biochem Mol Biol 2008; 150:170-6. [PMID: 18407536 DOI: 10.1016/j.cbpb.2008.02.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Revised: 02/26/2008] [Accepted: 02/26/2008] [Indexed: 02/04/2023]
Abstract
Eukaryotic elongation factor 1Bgamma (eEF1Bgamma) is a subunit of elongation factor 1 (EF1), which regulates the recruitment of amino acyl-tRNAs to the ribosome during protein synthesis in eukaryotes. In addition to structural roles within eEF1, eEF1Bgamma has properties which suggest sensory or regulatory activities. We have cloned eEF1Bgamma from axial abdominal muscle of freshwater crayfish, Procambarus clarkii. The predicted amino acid sequence has 66% identity to Locusta migratoria eEF1Bgamma and 65% identity to Artemia salina eEF1Bgamma. We measured eEF1Bgamma expression by real-time PCR, using the relative quantification method with 18s ribosomal RNA as an internal calibrator. eEF1Bgamma expression was lowest in gill, axial abdominal muscle, and hepatopancreas, and was highest in the antennal gland (5.7-fold above hepatopancreas) and cardiac muscle (7.8-fold above hepatopancreas). In axial abdominal muscle, eEF1Bgamma expression was 4.4-fold higher in premolt and 11.9 higher in postmolt compared to intermolt. In contrast, eEF1Bgamma was decreased or unchanged in epithelial tissues during pre- and postmolt. eEF1Bgamma expression in the hepatopancreas was 3.5-fold higher during intermolt compared to premolt and was unchanged in gill and antennal gland. No significant differences in eEF1Bgamma were found after 1 week of acclimation to 4 degrees C. These results show that eEF1Bgamma is regulated at the mRNA level with tissue-specific differences in expression patterns.
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29
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Prado MA, Casado P, Zuazua-Villar P, del Valle E, Artime N, Cabal-Hierro L, Martínez-Campa CM, Lazo PS, Ramos S. Phosphorylation of human eukaryotic elongation factor 1Bgamma is regulated by paclitaxel. Proteomics 2007; 7:3299-304. [PMID: 17708594 DOI: 10.1002/pmic.200700226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Paclitaxel (Ptx) is an antitumoural drug that inhibits microtubule dynamics, causes G2/M arrest and induces cell death. 2-D PAGE and MALDI-TOF-MS analysis of HeLa cells extracts revealed that Ptx up-regulates a form of the eukaryotic elongation factor 1Bgamma (eEF1Bgamma) and down-regulates another one. This event, linked to the lack of Ptx effect over eEF1Bgamma mRNA or protein levels suggested a PTM of this elongation factor. Further 2-D PAGE analysis followed by a phosphospecific staining with PRO-Q Diamond showed the staining of the Ptx up-regulated form only. Moreover, this Ptx up-regulated form of eEF1Bgamma disappears upon treatment with protein phosphatase. Thus, we demonstrate that human eEF1Bgamma phosphorylation is regulated by Ptx.
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Affiliation(s)
- Miguel A Prado
- Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
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30
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Gromadski KB, Schümmer T, Strømgaard A, Knudsen CR, Kinzy TG, Rodnina MV. Kinetics of the interactions between yeast elongation factors 1A and 1Balpha, guanine nucleotides, and aminoacyl-tRNA. J Biol Chem 2007; 282:35629-37. [PMID: 17925388 DOI: 10.1074/jbc.m707245200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The interactions of elongation factor 1A (eEF1A) from Saccharomyces cerevisiae with elongation factor 1Balpha (eEF1Balpha), guanine nucleotides, and aminoacyl-tRNA were studied kinetically by fluorescence stopped-flow. eEF1A has similar affinities for GDP and GTP, 0.4 and 1.1 microm, respectively. Dissociation of nucleotides from eEF1A in the absence of the guanine nucleotide exchange factor is slow (about 0.1 s(-1)) and is accelerated by eEF1Balpha by 320-fold and 250-fold for GDP and GTP, respectively. The rate constant of eEF1Balpha binding to eEF1A (10(7)-10(8) M (-1) s(-1)) is independent of guanine nucleotides. At the concentrations of nucleotides and factors prevailing in the cell, the overall exchange rate is expected to be in the range of 6 s(-1), which is compatible with the rate of protein synthesis in the cell. eEF1A.GTP binds Phe-tRNA(Phe) with a K(d) of 3 nm, whereas eEF1A.GDP shows no significant binding, indicating that eEF1A has similar tRNA binding properties as its prokaryotic homolog, EF-Tu.
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Affiliation(s)
- Kirill B Gromadski
- Institute of Physical Biochemistry, University of Witten/Herdecke, Stockumer Strasse 10, D-58448 Witten, Germany
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31
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Korsheninnikova E, Voshol PJ, Baan B, van der Zon GCM, Havekes LM, Romijn JA, Maassen JA, Ouwens DM. Dynamics of insulin signalling in liver during hyperinsulinemic euglycaemic clamp conditions in vivo and the effects of high-fat feeding in male mice. Arch Physiol Biochem 2007; 113:173-85. [PMID: 18158643 DOI: 10.1080/13813450701669084] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Insulin is an important regulator of hepatic carbohydrate, lipid, and protein metabolism, and the regulation of these processes by insulin is disturbed under conditions of insulin resistance and type 2 diabetes. Despite these alterations, the impact of insulin resistance on insulin signalling in the liver is not well defined. Variations in time and dose of insulin stimulation as well as plasma glucose levels may underlie this. The present study aimed at determining the dynamics of activation of hepatic insulin signalling in vivo at insulin concentrations resembling those achieved after a meal, and addressing the effects of high-fat feeding. An unexpected finding of this study was the biphasic activation pattern of the IRS-PI3K-PKB/Akt pathway. Our findings indicate that the first burst of activation contributes to regulation of glucose metabolism. The physiological function of the second peak is still unknown, but may involve regulation of protein synthesis. Finally, high-fat feeding caused hepatic insulin resistance, as illustrated by a reduced suppression of hepatic glucose production. A sustained increased phosphorylation of the serine/threonine kinases p70S6kinase and Jun N-terminal kinase in the absence of insulin may underlie the abrogated phosphorylation of the IRS proteins and their downstream targets.
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Affiliation(s)
- E Korsheninnikova
- Departments of Molecular Cell Biology, Leiden University Medical Centre, Leiden, The Netherlands
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Chang R, Wang E. Mouse translation elongation factor eEF1A-2 interacts with Prdx-I to protect cells against apoptotic death induced by oxidative stress. J Cell Biochem 2007; 100:267-78. [PMID: 16888816 DOI: 10.1002/jcb.20969] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
eEF1A-1 and eEF1A-2 are two isoforms of translation elongation factor eEF1A. In adult mammalian tissues, isoform eEF1A-1 is present in all tissues except neurons, cardiomyocytes, and myotubes, where its isoform, eEF1A-2, is the only form expressed. Both forms of eEF1A have been characterized to function in the protein elongation step of translation, and eEF1A-1 is shown to possess additional non-canonical roles in actin binding/bundling, microtubule bundling/severing, and cellular transformation processes. To study whether eEF1A-2 has similar non-canonical functions, we carried out a yeast two-hybrid screening using a full sequence of mouse eEF1A-2 as bait. A total of 78 hits, representing 23 proteins, were identified and validated to be true positives. We have focused on the protein with the highest frequency of hits, peroxiredoxin I (Prdx-I), for in-depth study of its functional implication for eEF1A-2. Here we show that Prdx-I coimmunoprecipitates with eEF1A-2 from extracts of both cultured cells and mouse tissues expressing this protein, but it does not do so with its isoform, eEF1A-1, even though the latter is abundantly present. We also report that an eEF1A-2 and Prdx-I double transfectant increases resistance to peroxide-induced cell death as high as 1 mM peroxide treatment, significantly higher than do single transfectants with either gene alone; this protection is correlated with reduced activation of caspases 3 and 8, and with increased expression of pro-survival factor Akt. Thus, our results suggest that eEF1A-2 interacts with Prdx-I to functionally provide cells with extraordinary resistance to oxidative stress-induced cell death.
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Affiliation(s)
- Ruying Chang
- Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
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Ong LL, Lin PC, Zhang X, Chia SM, Yu H. Kinectin-dependent assembly of translation elongation factor-1 complex on endoplasmic reticulum regulates protein synthesis. J Biol Chem 2006; 281:33621-34. [PMID: 16950774 DOI: 10.1074/jbc.m607555200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Kinectin is an integral membrane protein with many isoforms primarily found on the endoplasmic reticulum. It has been found to bind kinesin, Rho GTPase, and translation elongation factor-1delta. None of the existing models for the quaternary organization of the elongation factor-1 complex in higher eukaryotes involves kinectin. We have investigated here the assembly of the elongation factor-1 complex onto endoplasmic reticulum via kinectin using in vitro and in vivo assays. We established that the entire elongation factor-1 complex can be anchored to endoplasmic reticulum via kinectin, and the interacting partners are as follows. Kinectin binds EF-1delta, which in turn binds EF-1gamma but not EF-1beta; EF-1gamma binds EF-1delta and EF-1beta but not kinectin. In vivo splice blocking of the kinectin exons 36 and 37 produced kinectin lacking the EF-1delta binding domain, which disrupted the membrane localization of EF-1delta, EF-1gamma, and EF-1beta on endoplasmic reticulum, similar to the disruptions seen with the overexpression of kinectin fragments containing the EF-1delta binding domain. The disruptions of the EF-1delta/kinectin interaction inhibited expression of membrane proteins but enhanced synthesis of cytosolic proteins in vivo. These findings suggest that anchoring the elongation factor-1 complex onto endoplasmic reticulum via EF-1delta/kinectin interaction is important for regulating protein synthesis in eukaryotic cells.
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Affiliation(s)
- Lee-Lee Ong
- National University Medical Institutes, National University of Singapore, Singapore 117597, Singapore
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Baan B, van Dam H, van der Zon GCM, Maassen JA, Ouwens DM. The Role of c-Jun N-Terminal Kinase, p38, and Extracellular Signal-Regulated Kinase in Insulin-Induced Thr69 and Thr71 Phosphorylation of Activating Transcription Factor 2. Mol Endocrinol 2006; 20:1786-95. [PMID: 16601071 DOI: 10.1210/me.2005-0289] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The stimulation of cells with physiological concentrations of insulin induces a variety of responses, e.g. an increase in glucose uptake, induction of glycogen and protein synthesis, and gene expression. One of the determinants regulating insulin-mediated gene expression may be activating transcription factor 2 (ATF2). Insulin activates ATF2 by phosphorylation of Thr69 and Thr71 via a two-step mechanism, in which ATF2-Thr71 phosphorylation precedes the induction of ATF2-Thr69+71 phosphorylation by several minutes. We previously found that in c-Jun N-terminal kinase (JNK)-/- fibroblasts, cooperation of the ERK1/2 and p38 pathways is required for two-step ATF2-Thr69+71 phosphorylation in response to growth factors. Because JNK is also capable of phosphorylating ATF2, we assessed the involvement of JNK, ERK1/2 and p38 in the insulin-induced two-step ATF2 phosphorylation in JNK-expressing A14 fibroblasts and 3T3L1-adipocytes. The induction of ATF2-Thr71 phosphorylation was sensitive to MAPK kinase (MEK) 1/2-inhibition with U0126, and this phosphorylation coincided with nuclear translocation of phosphorylated ERK1/2. Use of the JNK inhibitor SP600125 or expression of dominant-negative JNK-activator SAPK kinase (SEK1) prevented the induction of ATF2-Thr69+71, but not ATF2-Thr71 phosphorylation by insulin. ATF2-dependent transcription was also sensitive to SP-treatment. Abrogation of p38 activation with SB203580 or expression of dominant-negative MKK6 had no inhibitory effect on these events. In agreement with this, the onset of ATF2-Thr69+71 phosphorylation coincided with the nuclear translocation of phosphorylated JNK. Finally, in vitro kinase assays using nuclear extracts indicated that ERK1/2 preceded JNK translocation. We conclude that sequential activation and nuclear appearance of ERK1/2 and JNK, rather than p38, underlies the two-step insulin-induced ATF2 phosphorylation in JNK-expressing cells.
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Affiliation(s)
- Bart Baan
- Department of Molecular Cell Biology, Section Signal Transduction and Ageing, Leiden University Medical Centre, The Netherlands
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35
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Ni JQ, Liu LP, Hess D, Rietdorf J, Sun FL. Drosophila ribosomal proteins are associated with linker histone H1 and suppress gene transcription. Genes Dev 2006; 20:1959-73. [PMID: 16816001 PMCID: PMC1522087 DOI: 10.1101/gad.390106] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Accepted: 05/08/2006] [Indexed: 11/24/2022]
Abstract
The dynamics and function of ribosomal proteins in the cell nucleus remain enigmatic. Here we provide evidence that specific components of Drosophila melanogaster ribosomes copurify with linker histone H1. Using various experimental approaches, we demonstrate that this association of nuclear ribosomal proteins with histone H1 is specific, and that colocalization occurs on condensed chromatin in vivo. Chromatin immunoprecipitation analysis confirmed that specific ribosomal proteins are associated with chromatin in a histone H1-dependent manner. Overexpression of either histone H1 or ribosomal protein L22 in Drosophila cells resulted in global suppression of the same set of genes, while depletion of H1 and L22 caused up-regulation of tested genes, suggesting that H1 and ribosomal proteins are essential for transcriptional gene repression. Overall, this study provides evidence for a previously undefined link between ribosomal proteins and chromatin, and suggests a role for this association in transcriptional regulation in higher eukaryotes.
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Affiliation(s)
- Jian-Quan Ni
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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Le Sourd F, Boulben S, Le Bouffant R, Cormier P, Morales J, Belle R, Mulner-Lorillon O. eEF1B: At the dawn of the 21st century. ACTA ACUST UNITED AC 2006; 1759:13-31. [PMID: 16624425 DOI: 10.1016/j.bbaexp.2006.02.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Revised: 02/21/2006] [Accepted: 02/22/2006] [Indexed: 12/18/2022]
Abstract
Translational regulation of gene expression in eukaryotes can rapidly and accurately control cell activity in response to stimuli or when rapidly dividing. There is increasing evidence for a key role of the elongation step in this process. Elongation factor-1 (eEF1), which is responsible for aminoacyl-tRNA transfer on the ribosome, is comprised of two entities: a G-protein named eEF1A and a nucleotide exchange factor, eEF1B. The multifunctional nature of eEF1A, as well as its oncogenic potential, is currently the subject of a number of studies. Until recently, less work has been done on eEF1B. This review describes the macromolecular complexity of eEF1B, its multiple phosphorylation sites and numerous cellular partners, which lead us to suggest an essential role for the factor in the control of gene expression, particularly during the cell cycle.
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Affiliation(s)
- Frédéric Le Sourd
- Equipe Cycle Cellulaire et Développement, Unité Mer and Sante, UMR 7150 CNRS/UPMC, Station Biologique de Roscoff, BP 74, 29682 Roscoff Cedex, France
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37
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McGoldrick S, McCarthy TV, Sheehan D. The 110kDa glutathione transferase of Yarrowia lipolytica is encoded by a homologue of the TEF3 gene from Saccharomyces cerevisiae: Cloning, expression, and homology modeling of the recombinant protein. Biochem Biophys Res Commun 2005; 337:1125-32. [PMID: 16229819 DOI: 10.1016/j.bbrc.2005.09.162] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Accepted: 09/21/2005] [Indexed: 12/01/2022]
Abstract
The TEF4 gene of the non-saccharomyces yeast Yarrowia lipolytica encodes an EF1Bgamma protein with structural similarity to the glutathione transferases (GSTs). This 1203bp gene was cloned, over-expressed in Escherichia coli, and the recombinant protein characterized. DNA sequencing of the cloned gene agreed with the recently completed Y. lipolytica genome and showed 100% identity to a previously reported 30-residue N-terminal sequence for a 110kDa Y. lipolytica GST, except that it encoded two additional N-terminal residues (N-Met-Ser-). The recombinant protein (subunit M(r) 52kDa) was found not to possess GST activity with 1-chloro-2,4-dinitrobenzene. Partial tryptic digestion released two fragments of M(r) 22 and 18kDa, which we interpret as N- and C-terminal domains. Homology modeling confirmed that the N-terminal domain of Y. lipolytica TEF4 encodes a GST-like protein.
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Affiliation(s)
- Shane McGoldrick
- Department of Biochemistry, University College Cork, Lee Maltings, Prospect Row, Mardyke, Cork, Ireland
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Lee SW, Cho BH, Park SG, Kim S. Aminoacyl-tRNA synthetase complexes: beyond translation. J Cell Sci 2005; 117:3725-34. [PMID: 15286174 DOI: 10.1242/jcs.01342] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although aminoacyl-tRNA synthetases (ARSs) are housekeeping enzymes essential for protein synthesis, they can play non-catalytic roles in diverse biological processes. Some ARSs are capable of forming complexes with each other and additional proteins. This characteristic is most pronounced in mammals, which produce a macromolecular complex comprising nine different ARSs and three additional factors: p43, p38 and p18. We have been aware of the existence of this complex for a long time, but its structure and function have not been well understood. The only apparent distinction between the complex-forming ARSs and those that do not form complexes is their ability to interact with the three non-enzymatic factors. These factors are required not only for the catalytic activity and stability of the associated ARSs, such as isoleucyl-, methionyl-, and arginyl-tRNA synthetase, but also for diverse signal transduction pathways. They may thus have joined the ARS community to coordinate protein synthesis with other biological processes.
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Affiliation(s)
- Sang Won Lee
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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Reddy KK, Oitomen FM, Patel GP, Bag J. Perinuclear localization of slow troponin C m RNA in muscle cells is controlled by a cis-element located at its 3' untranslated region. RNA (NEW YORK, N.Y.) 2005; 11:294-307. [PMID: 15701732 PMCID: PMC1370719 DOI: 10.1261/rna.5460105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2003] [Accepted: 12/07/2004] [Indexed: 05/24/2023]
Abstract
The process of mRNA localization within a specific cytoplasmic region is an integral aspect of the regulation of gene expression. Furthermore, colocalization of mRNAs and their respective translation products may facilitate the proper assembly of multi-subunit complexes like the thick and thin filaments of muscle. This postulate was tested by investigating the cytoplasmic localization of three mRNAs-the alpha-actin, slow troponin C (sTnC), and slow troponin I (sTnI), which encode different poly-peptide partners of the thin filament. Using in situ hybridization we showed that all three thin filament mRNAs are localized in the perinuclear cytoplasm of cultured C2C12 muscle cells. Their localization differs from that of the nonmuscle beta-actin mRNA, which is localized in the peripheral region of both proliferating nondifferentiated myoblasts and the differentiated myocytes. Analysis of the localization signal of the sTnC mRNA showed that a 40-nucleotide-long region of the sTnC mRNA 3' UTR is sufficient to confer the perinuclear localization on a heterologous reporter beta-Gal mRNA. This localization signal showed tissue specificity and worked only in the differentiated myocytes, but not in the proliferating myoblasts or in HeLa cells. The predicted secondary structure of the localization signal suggests the presence of multiple stem and loop structures in this region of the 3' UTR. Mutations within the stem region of the localization signal, which abolish the base pairing in this region, significantly reduced its perinuclear mRNA localization activity. Using UV-induced photo-cross-linking of RNA and proteins we found that a myotube-specific 42-kDa polypeptide binds to the localization signal.
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Affiliation(s)
- Kishore K Reddy
- Department of Molecular Biology and Genetics, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
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Tang RB, Chen YS, Chou H, Lee SS, Tai HY, Shen HD. cDNA cloning and immunologic characterization of a novel EF-1beta allergen from Penicillium citrinum. Allergy 2005; 60:366-71. [PMID: 15679724 DOI: 10.1111/j.1398-9995.2005.00706.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND We have identified previously that Penicillium citrinum is the most prevalent Penicillium species in the Taipei area. It is important to delineate the whole spectrum of allergenic components of this prevalent airborne fungus. The purpose of this study was to identify novel P. citrinum allergens through molecular cloning of allergen genes using a cDNA library of P. citrinum and sera from patients with bronchial asthma. METHODS A lambda-Uni-ZAP XR-based cDNA library of P. citrinum was screened with sera from asthmatic patients. An IgE-binding cDNA clone was isolated and heterologously expressed in Escherichia coli. The frequency of IgE-binding to the expressed protein and the IgE reactivity to allergen subunits were analyzed by immunoblotting. RESULTS An IgE-reactive cDNA clone (clone B) was isolated by plaque immunoassay. The cDNA insert is 876-bp long and encodes a 228-amino acid polypeptide with a calculated molecular mass of 25 035 Da. Protein database search with the deduced clone B sequence revealed that 121 (53%) and 82 (36%) of the 228 amino acids were identical to those of the elongation factor 1-beta (EF-1beta) proteins from the yeast Saccharomyces cerevisiae and the parasite Echinococcus granulosus, respectively. His-tagged recombinant clone B proteins were constructed and expressed in E. coli. Seven (8%) of the 92 serum samples from patients with bronchial asthma showed IgE-binding to the recombinant clone B protein. Among these seven positive sera, five demonstrated IgE-binding to the C-terminal fragment (aa 119-228) while the other two sera showed IgE reactivity to the N-terminal fragment (aa 1-118) of this newly identified EF-1betaPenicillium allergen. CONCLUSIONS A novel P. citrinum allergen (Pen c 24) was identified and characterized in the present study. Results obtained provide more information about allergens of prevalent airborne fungi and a basis to understand more about the IgE responses in human atopic disorders and in parasitic infections.
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Affiliation(s)
- R-B Tang
- Department of Pediatrics, Veterans General Hospital-Taipei, Taipei, Taiwan
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41
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Kim NS, Hahn Y, Oh JH, Lee JY, Oh KJ, Kim JM, Park HS, Kim S, Song KS, Rho SM, Yoo HS, Kim YS. Gene cataloging and expression profiling in human gastric cancer cells by expressed sequence tags. Genomics 2005; 83:1024-45. [PMID: 15177556 DOI: 10.1016/j.ygeno.2003.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Accepted: 12/04/2003] [Indexed: 12/14/2022]
Abstract
To understand the molecular mechanism associated with gastric carcinogenesis, we identified genes expressed in gastric cancer cell lines and tissues. Of 97,609 high-quality ESTs sequenced from 36 cDNA libraries, 92,545 were coalesced into 10,418 human Unigene clusters (Build 151). The gene expression profile was produced by counting the cluster frequencies in each library. Although the profiles of highly expressed genes varied greatly from library to library, those genes related to cell structure formation, heat shock proteins, the glycolysis pathway, and the signaling pathway were highly represented in human gastric cancer cell lines and in primary tumors. Conversely, the genes encoding immunoglobulins, ribosomal proteins, and digestive proteins were down-regulated in gastric cancer cell lines and tissues compared to normal tissues. The transcription levels of some of these genes were confirmed by RT-PCR. We found that genes related to cell adhesion, apoptosis, and cytoskeleton formation were particularly up-regulated in the gastric cancer cell lines established from malignant ascites compared to those from primary tumors. This comprehensive molecular profiling of human gastric cancer should be useful for elucidating the genetic events associated with human gastric cancer.
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Affiliation(s)
- Nam-Soon Kim
- Laboratory of Human Genomics, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, South Korea
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Vickers TJ, Wyllie S, Fairlamb AH. Leishmania major elongation factor 1B complex has trypanothione S-transferase and peroxidase activity. J Biol Chem 2004; 279:49003-9. [PMID: 15322082 DOI: 10.1074/jbc.m407958200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the Trypanosomatidae, trypanothione has subsumed many of the roles of glutathione in defense against chemical and oxidant stress. Crithidia fasciculata lacks glutathione S-transferase, but contains an unusual trypanothione S-transferase activity that is associated with eukaryotic translation elongation factor 1B (eEF1B). Here we describe the cloning, expression, and reconstitution of the purified alpha, beta, and gamma subunits of eEF1B from Leishmania major. Individual subunits lacked trypanothione S-transferase activity. Only eEF1B, formed by reconstitution or co-expression of the three subunits, was able to conjugate a variety of electrophilic substrates to trypanothione or glutathionylspermidine, but not glutathione. In contrast to the C. fasciculata eEF1B, the L. major enzyme also displayed peroxidase activity against a variety of organic hydroperoxides. The enzyme showed no activity with hydrogen peroxide and greatest activity with linoleic acid hydroperoxide (1 unit mg(-1)). Kinetic studies suggest a ternary complex mechanism, with Km values of 140 mum for trypanothione and 7.4 mm for cumene hydroperoxide and kcat=25 s(-1). Immunofluorescence studies indicate that the enzyme may be localized to the surface of the endoplasmic reticulum. These results suggest that, in addition to its role in protein synthesis, the Leishmania eEF1B may help protect the parasite from lipid peroxidation.
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Affiliation(s)
- Tim J Vickers
- Division of Biological Chemistry and Molecular Microbiology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, United Kingdom
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Kasparov S, Teschemacher AG, Hwang DY, Kim KS, Lonergan T, Paton JFR. Viral vectors as tools for studies of central cardiovascular control. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2004; 84:251-77. [PMID: 14769439 DOI: 10.1016/j.pbiomolbio.2003.11.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
During the last few years physiological genomics has been the most rapidly developing area of physiology. Given the current ease of obtaining information about nucleotide sequences found in genomes and the vast amount of readily available clones, one of the most pertinent tasks is to find out about the roles of the individual genes and their families under normal and pathological conditions. Viral gene delivery into the brain is a powerful tool, which can be used to address a wide range of questions posed by physiological genomics including central nervous mechanisms regulating the cardio-vascular system. In this paper, we will give a short overview of current data obtained in this field using viral vectors and then look critically at the technology of viral gene transfer.
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Affiliation(s)
- S Kasparov
- Department of Physiology, University of Bristol, Bristol, UK.
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Jeppesen MG, Ortiz P, Shepard W, Kinzy TG, Nyborg J, Andersen GR. The crystal structure of the glutathione S-transferase-like domain of elongation factor 1Bgamma from Saccharomyces cerevisiae. J Biol Chem 2003; 278:47190-8. [PMID: 12972429 DOI: 10.1074/jbc.m306630200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The crystal structure of the N-terminal 219 residues (domain 1) of the conserved eukaryotic translation elongation factor 1Bgamma (eEF1Bgamma), encoded by the TEF3 gene in Saccharomyces cerevisiae, has been determined at 3.0 A resolution by the single wavelength anomalous dispersion technique. The structure is overall very similar to the glutathione S-transferase proteins and contains a pocket with architecture highly homologous to what is observed in glutathione S-transferase enzymes. The TEF3-encoded form of eEF1Bgamma has no obvious catalytic residue. However, the second form of eEF1Bgamma encoded by the TEF4 gene contains serine 11, which may act catalytically. Based on the x-ray structure and gel filtration studies, we suggest that the yeast eEF1 complex is organized as an [eEF1A.eEF1Balpha.eEF1Bgamma]2 complex. A 23-residue sequence in the middle of eEF1Bgamma is essential for the stable dimerization of eEF1Bgamma and the quaternary structure of the eEF1 complex.
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Affiliation(s)
- Mads Gravers Jeppesen
- Department of Molecular Biology, University of Arhus, Gustav Wieds vej 10 C, 8000 Arhus C, Denmark
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Cans C, Passer BJ, Shalak V, Nancy-Portebois V, Crible V, Amzallag N, Allanic D, Tufino R, Argentini M, Moras D, Fiucci G, Goud B, Mirande M, Amson R, Telerman A. Translationally controlled tumor protein acts as a guanine nucleotide dissociation inhibitor on the translation elongation factor eEF1A. Proc Natl Acad Sci U S A 2003; 100:13892-7. [PMID: 14623968 PMCID: PMC283517 DOI: 10.1073/pnas.2335950100] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recently, we demonstrated that the expression levels of the translationally controlled tumor protein (TCTP) were strongly down-regulated at the mRNA and protein levels during tumor reversion/suppression and by the activation of p53 and Siah-1. To better characterize the function of TCTP, a yeast two-hybrid hunt was performed. Subsequent analysis identified the translation elongation factor, eEF1A, and its guanine nucleotide exchange factor, eEF1Bbeta, as TCTP-interacting partners. In vitro and in vivo studies confirmed that TCTP bound specifically eEF1Bbeta and eEF1A. Additionally, MS analysis also identified eEF1A as a TCTP interactor. Because eEF1A is a GTPase, we investigated the role of TCTP on the nucleotide exchange reaction of eEF1A. Our results show that TCTP preferentially stabilized the GDP form of eEF1A, and, furthermore, impaired the GDP exchange reaction promoted by eEF1Bbeta. These data suggest that TCTP has guanine nucleotide dissociation inhibitor activity, and, moreover, implicate TCTP in the elongation step of protein synthesis.
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Affiliation(s)
- Christophe Cans
- Molecular Engines Laboratories, 20 Rue Bouvier, 75011 Paris, France
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Cho DI, Oak MH, Yang HJ, Choi HK, Janssen GMC, Kim KM. Direct and biochemical interaction between dopamine D3 receptor and elongation factor-1Bbetagamma. Life Sci 2003; 73:2991-3004. [PMID: 14519448 DOI: 10.1016/s0024-3205(03)00707-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Novel signaling components of dopamine D3 receptor (D3R) were searched using yeast two-hybrid system, and the gamma subunit of elongation Factor-1B (eEF1Bgamma) was found to interact with D3R. This interaction was observed specifically between eEF1Bgamma and D3R but not with D2R or D4R. Immunocytochemical studies showed that D3R and eEF1Bgamma form clusters on the plasma membrane and their co-localization was evident in these clusters. The beta subunit of eEF1B (eEF1Bbeta), which forms a tight complex with eEF1Bgamma, was phosphorylated on serine residues in response to the stimulation of D3R. Phosphorylation of eEF1Bbeta was insensitive to pertussis toxin or wortmannin, however, stimulation of cellular protein kinase C (PKC) directly phosphorylated eEF1Bbeta and depletion of PKC abolished D3R-mediated phosphorylation of eEF1Bbeta. These results suggest the involvement of PKC, but not Gi/o proteins or phosphatidylinositol 3-kinase, in D3R-mediated phosphorylation of eEF1Bbeta. Stimulation of D3R did not activate PKC, but the activation of PKC resulted in the phosphorylation of D3R. These results show that PKC has a permissive role for the D3R-mediated phosphorylation of eEF1Bbeta, and suggest that PKC could modulate the mutual interaction between two protein by phosphorylating both D3R and eEF1Bbeta. Therefore, the cellular PKC level would be important for the D3R-mediated modulation of eEF1B, and for their cellular regulations such as protein synthesis or cellular proliferation.
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Affiliation(s)
- Dong-Im Cho
- Department of Pharmacology and Research Institute of Drug Development, College of Pharmacy, Chonnam National University, Kwang-Ju 500-757, South Korea
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Ong LL, Er CPN, Ho A, Aung MT, Yu H. Kinectin anchors the translation elongation factor-1 delta to the endoplasmic reticulum. J Biol Chem 2003; 278:32115-23. [PMID: 12773547 DOI: 10.1074/jbc.m210917200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Kinectin has been proposed to be a membrane anchor for kinesin on intracellular organelles. A kinectin isoform that lacks a major portion of the kinesin-binding domain does not bind kinesin but interacts with another resident of the endoplasmic reticulum, the translation elongation factor-1 delta (EF-1 delta). This was shown by yeast two-hybrid analysis and a number of in vitro and in vivo assays. EF-1 delta provides the guanine nucleotide exchange activities on EF-1 alpha during elongation step of protein synthesis. The minimal EF-1 delta-binding domain on kinectin resides within a conserved region present in all the kinectin isoforms. Overexpression of the kinectin fragments in vivo disrupted the intracellular localization of EF-1 delta proteins. This report provides evidence of an alternative kinectin function as the membrane anchor for EF-1 delta on the endoplasmic reticulum and provides clues to the EF-1 complex assembly and anchorage on the endoplasmic reticulum.
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Affiliation(s)
- Lee-Lee Ong
- National University Medical Institutes and Department of Physiology, Faculty of Medicine, National University of Singapore, Singapore 117597
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Dapas B, Tell G, Scaloni A, Pines A, Ferrara L, Quadrifoglio F, Scaggiante B. Identification of different isoforms of eEF1A in the nuclear fraction of human T-lymphoblastic cancer cell line specifically binding to aptameric cytotoxic GT oligomers. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:3251-62. [PMID: 12869201 DOI: 10.1046/j.1432-1033.2003.03713.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
GT oligomers, showing a dose-dependent cytotoxic effect on a variety of human cancer cell lines, but not on normal human lymphocytes, recognize and form complexes with nuclear proteins. By working with human T-lymphoblastic CCRF-CEM cells and by using MS and SouthWestern blotting, we identified eukaryotic elongation factor 1 alpha (eEF1A) as the main nuclear protein that specifically recognizes these oligonucleotides. Western blotting and supershift assays confirmed the nature of this protein and its involvement in forming a cytotoxicity-related complex (CRC). On the contrary, normal human lymphocytes did not show nuclear proteins able to produce CRC in a SouthWestern blot. Comparative bidimensional PAGE and Western-blotting analysis for eEF1A revealed the presence of a specific cluster of spots, focusing at more basic pH, in nuclear extracts of cancer cells but absent in those of normal lymphocytes. Moreover, a bidimensional PAGE SouthWestern blot demonstrated that cytotoxic GT oligomers selectively recognized the more basic eEF1A isoform expressed only in cancer cells. These results suggest the involvement of eEF1A, associated with the nuclear-enriched fraction, in the growth and maintenance of tumour cells, possibly modulated by post-translational processing of the polypeptide chain.
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Affiliation(s)
- Barbara Dapas
- Department of Biomedical Sciences and Technologies, University of Udine, Italy
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49
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Kawaguchi Y, Kato K, Tanaka M, Kanamori M, Nishiyama Y, Yamanashi Y. Conserved protein kinases encoded by herpesviruses and cellular protein kinase cdc2 target the same phosphorylation site in eukaryotic elongation factor 1delta. J Virol 2003; 77:2359-68. [PMID: 12551973 PMCID: PMC141098 DOI: 10.1128/jvi.77.4.2359-2368.2003] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Earlier studies have shown that translation elongation factor 1delta (EF-1delta) is hyperphosphorylated in various mammalian cells infected with representative alpha-, beta-, and gammaherpesviruses and that the modification is mediated by conserved viral protein kinases encoded by herpesviruses, including UL13 of herpes simplex virus type 1 (HSV-1), UL97 of human cytomegalovirus, and BGLF4 of Epstein-Barr virus (EBV). In the present study, we attempted to identify the site in EF-1delta associated with the hyperphosphorylation by the herpesvirus protein kinases. Our results are as follows: (i) not only in infected cells but also in uninfected cells, replacement of the serine residue at position 133 (Ser-133) of EF-1delta by alanine precluded the posttranslational processing of EF-1delta, which corresponds to the hyperphosphorylation. (ii) A purified chimeric protein consisting of maltose binding protein (MBP) fused to a domain of EF-1delta containing Ser-133 (MBP-EFWt) is specifically phosphorylated in in vitro kinase assays by purified recombinant UL13 fused to glutathione S-transferase (GST) expressed in the baculovirus system. In contrast, the level of phosphorylation by the recombinant UL13 of MBP-EFWt carrying an alanine replacement of Ser-133 (MBP-EFS133A) was greatly impaired. (iii) MBP-EFWt is also specifically phosphorylated in vitro by purified recombinant BGLF4 fused to GST expressed in the baculovirus system, and the level of phosphorylation of MBP-EFS133A by the recombinant BGLF4 was greatly reduced. (iv) The sequence flanking Ser-133 of EF-1delta completely matches the consensus phosphorylation site for a cellular protein kinase, cdc2, and in vitro kinase assays revealed that purified cdc2 phosphorylates Ser-133 of EF-1delta. (v) As observed with EF-1delta, the casein kinase II beta subunit (CKIIbeta) was specifically phosphorylated by UL13 in vitro, while the level of phosphorylation of CKIIbeta by UL13 was greatly diminished when a serine residue at position 209, which has been reported to be phosphorylated by cdc2, was replaced with alanine. These results indicate that the conserved protein kinases encoded by herpesviruses and a cellular protein kinase, cdc2, have the ability to target the same amino acid residues for phosphorylation. Our results raise the possibility that the viral protein kinases mimic cdc2 in infected cells.
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Affiliation(s)
- Yasushi Kawaguchi
- Department of Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan.
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Nathanson L, Xia T, Deutscher MP. Nuclear protein synthesis: a re-evaluation. RNA (NEW YORK, N.Y.) 2003; 9:9-13. [PMID: 12554870 PMCID: PMC1370364 DOI: 10.1261/rna.2990203] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2002] [Accepted: 08/28/2002] [Indexed: 05/21/2023]
Abstract
It has been reported that nuclei from HeLa cells are responsible for approximately 10%-15% of total cellular protein synthesis. We show here that isolated Chinese hamster ovary (CHO) and HeLa cell nuclei are essentially inactive for translation, and that the earlier results were most likely due to cytoplasmic contamination. Moreover, we suggest that the nascent polypeptides observed in nuclei of permeabilized cells may have been due to "overpermeabilization" and consequent damage to the cells. Based on this information, we conclude that nuclear protein synthesis, if it exists, is limited to less than 1% of that in cells.
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