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Guo K, Zhou J. Insights into eukaryotic translation initiation factor 5A: Its role and mechanisms in protein synthesis. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119849. [PMID: 39303786 DOI: 10.1016/j.bbamcr.2024.119849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 08/29/2024] [Accepted: 09/12/2024] [Indexed: 09/22/2024]
Abstract
The protein synthesis within eukaryotic cells is a complex process involving various translation factors. Among these factors, eukaryotic translation initiation factor 5 A (eIF5A) emerges as a crucial translation factor with high evolutionary conservation. eIF5A is unique as it is the only protein in eukaryotic cells containing the hypusine modification. Initially presumed to be a translation initiation factor, eIF5A was subsequently discovered to act mainly during the translation elongation phase. Notably, eIF5A facilitates the translation of peptide sequences containing polyproline stretches and exerts a universal regulatory effect on the elongation and termination phases of protein synthesis. Additionally, eIF5A indirectly affects various physiological processes within the cell by modulating the translation of specific proteins. This review provides a comprehensive overview of the structure, physiological functions, various post-translational modifications of eIF5A, and its association with various human diseases. The comparison between eIF5A and its bacterial homolog, EF-P, extends the discussion to the evolutionary conservation of eIF5A. This highlights its significance across different domains of life.
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Affiliation(s)
- Keying Guo
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Jie Zhou
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China.
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Barba-Aliaga M, Alepuz P. Role of eIF5A in Mitochondrial Function. Int J Mol Sci 2022; 23:1284. [PMID: 35163207 PMCID: PMC8835957 DOI: 10.3390/ijms23031284] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 12/17/2022] Open
Abstract
The eukaryotic translation initiation factor 5A (eIF5A) is an evolutionarily conserved protein that binds ribosomes to facilitate the translation of peptide motifs with consecutive prolines or combinations of prolines with glycine and charged amino acids. It has also been linked to other molecular functions and cellular processes, such as nuclear mRNA export and mRNA decay, proliferation, differentiation, autophagy, and apoptosis. The growing interest in eIF5A relates to its association with the pathogenesis of several diseases, including cancer, viral infection, and diabetes. It has also been proposed as an anti-aging factor: its levels decay in aged cells, whereas increasing levels of active eIF5A result in the rejuvenation of the immune and vascular systems and improved brain cognition. Recent data have linked the role of eIF5A in some pathologies with its function in maintaining healthy mitochondria. The eukaryotic translation initiation factor 5A is upregulated under respiratory metabolism and its deficiency reduces oxygen consumption, ATP production, and the levels of several mitochondrial metabolic enzymes, as well as altering mitochondria dynamics. However, although all the accumulated data strongly link eIF5A to mitochondrial function, the precise molecular role and mechanisms involved are still unknown. In this review, we discuss the findings linking eIF5A and mitochondria, speculate about its role in regulating mitochondrial homeostasis, and highlight its potential as a target in diseases related to energy metabolism.
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Affiliation(s)
- Marina Barba-Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
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3
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Cheng Y, Zhu H, Du Z, Guo X, Zhou C, Wang Z, He X. Eukaryotic translation factor eIF5A contributes to acetic acid tolerance in Saccharomyces cerevisiae via transcriptional factor Ume6p. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:38. [PMID: 33557922 PMCID: PMC7869214 DOI: 10.1186/s13068-021-01885-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/16/2021] [Indexed: 05/10/2023]
Abstract
BACKGROUND Saccharomyces cerevisiae is well-known as an ideal model system for basic research and important industrial microorganism for biotechnological applications. Acetic acid is an important growth inhibitor that has deleterious effects on both the growth and fermentation performance of yeast cells. Comprehensive understanding of the mechanisms underlying S. cerevisiae adaptive response to acetic acid is always a focus and indispensable for development of robust industrial strains. eIF5A is a specific translation factor that is especially required for the formation of peptide bond between certain residues including proline regarded as poor substrates for slow peptide bond formation. Decrease of eIF5A activity resulted in temperature-sensitive phenotype of yeast, while up-regulation of eIF5A protected transgenic Arabidopsis against high temperature, oxidative or osmotic stress. However, the exact roles and functional mechanisms of eIF5A in stress response are as yet largely unknown. RESULTS In this research, we compared cell growth between the eIF5A overexpressing and the control S. cerevisiae strains under various stressed conditions. Improvement of acetic acid tolerance by enhanced eIF5A activity was observed all in spot assay, growth profiles and survival assay. eIF5A prompts the synthesis of Ume6p, a pleiotropic transcriptional factor containing polyproline motifs, mainly in a translational related way. As a consequence, BEM4, BUD21 and IME4, the direct targets of Ume6p, were up-regulated in eIF5A overexpressing strain, especially under acetic acid stress. Overexpression of UME6 results in similar profiles of cell growth and target genes transcription to eIF5A overexpression, confirming the role of Ume6p and its association between eIF5A and acetic acid tolerance. CONCLUSION Translation factor eIF5A protects yeast cells against acetic acid challenge by the eIF5A-Ume6p-Bud21p/Ime4p/Bem4p axles, which provides new insights into the molecular mechanisms underlying the adaptive response and tolerance to acetic acid in S. cerevisiae and novel targets for construction of robust industrial strains.
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Affiliation(s)
- Yanfei Cheng
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hui Zhu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhengda Du
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuena Guo
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chenyao Zhou
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhaoyue Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiuping He
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Liang S, Dong H, Zhu S, Zhao Q, Huang B, Yu Y, Wang Q, Wang H, Yu S, Han H. Eimeria tenella Translation Initiation Factor eIF-5A That Interacts With Calcium-Dependent Protein Kinase 4 Is Involved in Host Cell Invasion. Front Cell Infect Microbiol 2021; 10:602049. [PMID: 33553005 PMCID: PMC7862772 DOI: 10.3389/fcimb.2020.602049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/04/2020] [Indexed: 11/17/2022] Open
Abstract
Eimeria tenella is an apicomplexan, parasitic protozoan known to infect poultry worldwide. An important calcium-dependent protein kinase (CDPK) has been identified in plants, green algae, ciliates and apicomplexan, such as E. tenella. CDPKs are effector molecules involved in calcium signaling pathways, which control important physiological processes such as gliding motility, reproduction, and host cell invasion. Given that CDPKs are not found in the host, studying the functions of CDPKs in E. tenella may serve as a basis for developing new therapeutic drugs and vaccines. To assess the function of CDPK4 in E. tenella (EtCDPK4), a putative interactor, translation initiation factor eIF-5A (EteIF-5A), was screened by both co-immunoprecipitation (co-IP) and His pull-down assays followed by mass spectrometry. The interaction between EteIF-5A and EtCDPK4 was determined by bimolecular fluorescence complementation (BiFC), GST pull-down, and co-IP. The molecular characteristics of EteIF-5A were then analyzed. Quantitative real-time polymerase chain reaction and western blotting were used to determine the transcription and protein levels of EteIF-5A in the different developmental stages of E. tenella. The results showed that the transcription level of EteIF-5A mRNA was highest in second-generation merozoites, and the protein expression level was highest in unsporulated oocysts. Indirect immunofluorescence showed that the EteIF-5A protein was found throughout the cytoplasm of sporozoites, but not in the refractile body. As the invasion of DF-1 cells progressed, EteIF-5A fluorescence intensity increased in trophozoites, decreased in immature schizonts, and increased in mature schizonts. The secretion assay results, analyzed by western blotting, indicated that EteIF-5A was a secreted protein but not from micronemes. The results of invasion inhibition assays showed that rabbit anti-rEteIF-5A polyclonal antibodies effectively inhibited cell invasion by sporozoites, with an inhibition rate of 48%.
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Affiliation(s)
- Shanshan Liang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
- College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Hui Dong
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Shunhai Zhu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Qiping Zhao
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Bing Huang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Yu Yu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
- College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Qingjie Wang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Haixia Wang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Shuilan Yu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Hongyu Han
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
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Yoon CS, Kim MK, Kim YS, Lee SK. In vivo protein expression changes in mouse livers treated with dialyzed coffee extract as determined by IP-HPLC. Maxillofac Plast Reconstr Surg 2018; 40:44. [PMID: 30613574 PMCID: PMC6308107 DOI: 10.1186/s40902-018-0183-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 11/26/2018] [Indexed: 02/06/2023] Open
Abstract
Background Coffee extract has been investigated by many authors, and many minor components of coffee are known, such as polyphenols, diterpenes (kahweol and cafestol), melanoidins, and trigonelline, to have anti-inflammatory, anti-oxidant, anti-angiogenic, anticancer, chemoprotective, and hepatoprotective effects. Therefore, it is necessary to know its pharmacological effect on hepatocytes which show the most active cellular regeneration in body. Methods In order to determine whether coffee extract has a beneficial effect on the liver, 20 C57BL/6J mice were intraperitoneally injected once with dialyzed coffee extract (DCE)-2.5 (equivalent to 2.5 cups of coffee a day in man), DCE-5, or DCE-10, or normal saline (control), and then followed by histological observation and IP-HPLC (immunoprecipitation high performance liquid chromatography) over 24 h. Results Mice treated with DCE-2.5 or DCE-5 showed markedly hypertrophic hepatocytes with eosinophilic cytoplasms, while those treated with DCE-10 showed slightly hypertrophic hepatocytes, which were well aligned in hepatic cords with increased sinusoidal spaces. DCE induced the upregulations of cellular proliferation, growth factor/RAS signaling, cellular protection, p53-mediated apoptosis, angiogenesis, and antioxidant and protection-related proteins, and the downregulations of NFkB signaling proteins, inflammatory proteins, and oncogenic proteins in mouse livers. These protein expression changes induced by DCE were usually limited to the range ± 10%, suggesting murine hepatocytes were safely reactive to DCE within the threshold of physiological homeostasis. DCE-2.5 and DCE-5 induced relatively mild dose-dependent changes in protein expressions for cellular regeneration and de novo angiogenesis as compared with non-treated controls, whereas DCE-10 induced fluctuations in protein expressions. Conclusion These observations suggested that DCE-2.5 and DCE-5 were safer and more beneficial to murine hepatocytes than DCE-10. It was also found that murine hepatocytes treated with DCE showed mild p53-mediated apoptosis, followed by cellular proliferation and growth devoid of fibrosis signaling (as determined by IP-HPLC), and subsequently progressed to rapid cellular regeneration and wound healing in the absence of any inflammatory reaction based on histologic observations. Electronic supplementary material The online version of this article (10.1186/s40902-018-0183-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cheol Soo Yoon
- 1Department of Oral Pathology, College of Dentistry, Gangneung-Wonju National University and Institute of Oral Science, 123 Chibyun-dong, Gangneung, 210-702 South Korea
| | - Min Keun Kim
- 2Department of Oral and Maxillofacial Surgery, College of Dentistry, Gangneung-Wonju National University and Institute of Oral Science, Gangneung, South Korea
| | - Yeon Sook Kim
- 3Department of Dental Hygiene, College of Health Sciences, Cheongju University, Cheongju, South Korea
| | - Suk Keun Lee
- 1Department of Oral Pathology, College of Dentistry, Gangneung-Wonju National University and Institute of Oral Science, 123 Chibyun-dong, Gangneung, 210-702 South Korea
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Turpaev KT. Translation Factor eIF5A, Modification with Hypusine and Role in Regulation of Gene Expression. eIF5A as a Target for Pharmacological Interventions. BIOCHEMISTRY. BIOKHIMIIA 2018; 83:863-873. [PMID: 30208826 DOI: 10.1134/s0006297918080011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/09/2018] [Indexed: 12/22/2022]
Abstract
Translation factor eIF5A participates in protein synthesis at the stage of polypeptide chain elongation. Two eIF5A isoforms are known that are encoded by related genes whose expression varies significantly in different tissues. The eIF5A1 isoform is a constitutively and ubiquitously expressed gene, while the eIF5A2 isoform is expressed in few normal tissues and is an oncogene by a number of parameters. Unique feature of eIF5A isoforms is that they are the only two proteins that contain amino acid hypusine. Modification with hypusine is critical requirement for eIF5A activity. Another distinctive feature of eIF5A is its involvement in the translation of only a subset of the total population of cell mRNAs. The genes for which mRNAs translation requires eIF5A are the members of certain functional groups and are involved in cell proliferation, apoptosis, inflammatory processes, and regulation of transcription and RNA metabolism. The involvement of eIF5A is necessary for the translation of proteins containing oligoproline fragments and some other structures. Modification of eIF5A by hypusine is implemented by two highly specialized enzymes, deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH), which are not involved in other biochemical reactions. Intracellular activity of these enzymes is closely associated with systems of protein acetylation, polyamine metabolism and other biochemical processes. Inhibition of DHS and DOHH activity provides the possibility of pharmacological control of eIF5A activity and expression of eIF5A-dependent genes.
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Affiliation(s)
- K T Turpaev
- Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia.
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Pereira KD, Tamborlin L, Meneguello L, de Proença ARG, Almeida ICDPA, Lourenço RF, Luchessi AD. Alternative Start Codon Connects eIF5A to Mitochondria. J Cell Physiol 2016; 231:2682-9. [PMID: 27414022 DOI: 10.1002/jcp.25370] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 03/04/2016] [Indexed: 01/02/2023]
Abstract
Eukaryotic translation initiation factor 5A (eIF5A), a protein containing the amino acid residue hypusine required for its activity, is involved in a number of physiological and pathological cellular processes. In humans, several EIF5A1 transcript variants encode the canonical eIF5A1 isoform B, whereas the hitherto uncharacterized variant A is expected to code for a hypothetical eIF5A1 isoform, referred to as isoform A, which has an additional N-terminal extension. Herein, we validate the existence of eIF5A1 isoform A and its production from transcript variant A. In fact, variant A was shown to encode both eIF5A1 isoforms A and B. Mutagenic assays revealed different efficiencies in the start codons present in variant A, contributing to the production of isoform B at higher levels than isoform A. Immunoblotting and mass spectrometric analyses showed that isoform A can undergo hypusination and acetylation at specific lysine residues, as observed for isoform B. Examination of the N-terminal extension suggested that it might confer mitochondrial targeting. Correspondingly, we found that isoform A, but not isoform B, co-purified with mitochondria when the proteins were overproduced. These findings suggest that eIF5A1 isoform A has a role in mitochondrial function. J. Cell. Physiol. 231: 2682-2689, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Karina Danielle Pereira
- Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
- Institute of Biosciences, São Paulo State University, Rio Claro, São Paulo, Brazil
| | - Letícia Tamborlin
- Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
| | - Letícia Meneguello
- Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
- Institute of Biosciences, São Paulo State University, Rio Claro, São Paulo, Brazil
| | | | | | - Rogério Ferreira Lourenço
- Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
| | - Augusto Ducati Luchessi
- Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
- Institute of Biosciences, São Paulo State University, Rio Claro, São Paulo, Brazil
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Ser/Thr kinases and polyamines in the regulation of non-canonical functions of elongation factor 1A. Amino Acids 2016; 48:2339-52. [DOI: 10.1007/s00726-016-2311-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 08/08/2016] [Indexed: 10/21/2022]
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Rossi D, Barbosa NM, Galvão FC, Boldrin PEG, Hershey JWB, Zanelli CF, Fraser CS, Valentini SR. Evidence for a Negative Cooperativity between eIF5A and eEF2 on Binding to the Ribosome. PLoS One 2016; 11:e0154205. [PMID: 27115996 PMCID: PMC4845985 DOI: 10.1371/journal.pone.0154205] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 04/10/2016] [Indexed: 01/04/2023] Open
Abstract
eIF5A is the only protein known to contain the essential and unique amino acid residue hypusine. eIF5A functions in both translation initiation due to its stimulation of methionyl-puromycin synthesis and translation elongation, being highly required for peptide-bound formation of specific ribosome stalling sequences such as poly-proline. The functional interaction between eIF5A, tRNA, and eEF2 on the surface of the ribosome is further clarified herein. Fluorescence anisotropy assays were performed to determine the affinity of eIF5A to different ribosomal complexes and reveal its interaction exclusively and directly with the 60S ribosomal subunit in a hypusine-dependent manner (Ki60S-eIF5A-Hyp = 16 nM, Ki60S-eIF5A-Lys = 385 nM). A 3-fold increase in eIF5A affinity to the 80S is observed upon charged-tRNAiMet binding, indicating positive cooperativity between P-site tRNA binding and eIF5A binding to the ribosome. Previously identified conditional mutants of yeast eIF5A, eIF5AQ22H/L93F and eIF5AK56A, display a significant decrease in ribosome binding affinity. Binding affinity between ribosome and eIF5A-wild type or mutants eIF5AK56A, but not eIF5AQ22H/L93F, is impaired in the presence of eEF2 by 4-fold, consistent with negative cooperativity between eEF2 and eIF5A binding to the ribosome. Interestingly, high-copy eEF2 is toxic only to eIF5AQ22H/L93F and causes translation elongation defects in this mutant. These results suggest that binding of eEF2 to the ribosome alters its conformation, resulting in a weakened affinity of eIF5A and impairment of this interplay compromises cell growth due to translation elongation defects.
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Affiliation(s)
- Danuza Rossi
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
- Department of Molecular and Cellular Biology, University of California Davis, Davis, CA, United States of America, 95616
| | - Natalia M. Barbosa
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
| | - Fabio C. Galvão
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
| | - Paulo E. G. Boldrin
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
| | - John W. B. Hershey
- Department of Molecular and Cellular Biology, University of California Davis, Davis, CA, United States of America, 95616
| | - Cleslei F. Zanelli
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
| | - Christopher S. Fraser
- Department of Molecular and Cellular Biology, University of California Davis, Davis, CA, United States of America, 95616
| | - Sandro R. Valentini
- School of Pharmaceutical Sciences, UNESP - Univ Estadual Paulista, Department of Biological Sciences, Araraquara, SP, Brazil, 14801
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Mathews MB, Hershey JWB. The translation factor eIF5A and human cancer. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1849:836-44. [PMID: 25979826 PMCID: PMC4732523 DOI: 10.1016/j.bbagrm.2015.05.002] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 12/14/2022]
Abstract
The eukaryotic initiation factor eIF5A is a translation factor that, unusually, has been assigned functions in both initiation and elongation. Additionally, it is implicated in transcription, mRNA turnover and nucleocytoplasmic transport. Two eIF5A isoforms are generated from distinct but related genes. The major isoform, eIF5A1, is considered constitutive, is abundantly expressed in most cells, and is essential for cell proliferation. The second isoform, eIF5A2, is expressed in few normal tissues but is highly expressed in many cancers and has been designated a candidate oncogene. Elevated expression of either isoform carries unfavorable prognostic implications for several cancers, and both have been advanced as cancer biomarkers. The amino acid hypusine, a presumptively unique eIF5A post-translational modification, is required for most known eIF5A functions and it renders eIF5A susceptible to inhibitors of the modification pathway as therapeutic targets. eIF5A has been shown to regulate a number of gene products specifically, termed the eIF5A regulon, and its role in translating proline-rich sequences has recently been identified. A model is advanced that accommodates eIF5A in both the initiation and elongation phases of translation. We review here the biochemical functions of eIF5A, the relationship of its isoforms with human cancer, and evolving clinical applications. This article is part of a Special Issue entitled: Translation and Cancer.
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Affiliation(s)
- Michael B Mathews
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ 07103, USA.
| | - John W B Hershey
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA 95616, USA.
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11
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Abstract
In addition to the small and large ribosomal subunits, aminoacyl-tRNAs, and an mRNA, cellular protein synthesis is dependent on translation factors. The eukaryotic translation initiation factor 5A (eIF5A) and its bacterial ortholog elongation factor P (EF-P) were initially characterized based on their ability to stimulate methionyl-puromycin (Met-Pmn) synthesis, a model assay for protein synthesis; however, the function of these factors in cellular protein synthesis has been difficult to resolve. Interestingly, a conserved lysine residue in eIF5A is post-translationally modified to hypusine and the corresponding lysine residue in EF-P from at least some bacteria is modified by the addition of a β-lysine moiety. In this review, we provide a summary of recent data that have identified a novel role for the translation factor eIF5A and its hypusine modification in the elongation phase of protein synthesis and more specifically in stimulating the production of proteins containing runs of consecutive proline residues.
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Affiliation(s)
- Thomas E. Dever
- Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Erik Gutierrez
- Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Byung-Sik Shin
- Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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12
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Qin X, Liu X, Shan B, Shi L, Sharma S, Wu J, Lin Y. Inhibition of eIF5A results in aberrant uterine natural killer cell function and embryo loss in mice. Am J Reprod Immunol 2014; 71:229-40. [PMID: 24382123 PMCID: PMC4030494 DOI: 10.1111/aji.12194] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 12/03/2013] [Indexed: 01/20/2023] Open
Abstract
PROBLEM The role of eukaryotic initiation factor 5A (eIF5A) in feto-maternal immunotolerance is poorly understood. METHODS OF STUDY The effects of N1-guanyl-1,7-diaminoheptane (GC7), an inhibitor of eIF5A, on the proportion and function of natural killer (NK) cell subsets were investigated using flow cytometry, immunofluorescence, CCK8 assay, TUNEL assay, DNA fragmentation analysis, mitochondrial membrane potential assay, and Western blotting. RESULTS Inhibition of eIF5A by GC7 increased embryo loss and reduced the percentage of NK cells in the uterus and spleen. GC7 treatment caused inhibition of NK cell proliferation in a time- and dose-dependent manner. GC7 also induced apoptosis of NK cells. GC7 treatment increased the protein levels of FasL, bax, p53, and cleaved caspase-3. Moreover, GC7 caused loss of mitochondrial membrane potential in NK cells. CONCLUSION Inhibition of eIF5A results in aberrant NK cell function and increased embryo loss.
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Affiliation(s)
- Xiaoli Qin
- Department of Obstetrics and Gynecology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Xiaorui Liu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Bin Shan
- Medical Sciences, Washington State University Spokane, Spokane, WA, USA
| | - Lijuan Shi
- Department of Obstetrics and Gynecology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Surendra Sharma
- Department of Pediatrics, Women and Infants Hospital of Rhode Island, Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Ji Wu
- Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Bio-X Institutes, Shanghai Jiao Tong University, Shanghai, China
| | - Yi Lin
- Department of Obstetrics and Gynecology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
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13
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Rossi D, Galvão FC, Bellato HM, Boldrin PEG, Andrews BJ, Valentini SR, Zanelli CF. eIF5A has a function in the cotranslational translocation of proteins into the ER. Amino Acids 2014; 46:645-53. [PMID: 24306454 DOI: 10.1007/s00726-013-1618-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 11/01/2013] [Indexed: 10/25/2022]
Abstract
The putative eukaryotic translation initiation factor 5A (eIF5A) is a highly conserved and essential protein present in all organisms except bacteria. To be activated, eIF5A requires the conversion of a specific residue of lysine into hypusine. This hypusine modification occurs posttranslationally in two enzymatic steps, and the polyamine spermidine is the substrate. Despite having an essential function in translation elongation, the critical role played by eIF5A remains unclear. In addition to demonstrating genetic interactions with translation factors, eIF5A mutants genetically interact with mutations in YPT1, which encodes an essential protein involved in endoplasmic reticulum (ER)-to-Golgi vesicle transport. In this study, we investigated the correlation between the function of eIF5A in translation and secretion in yeast. The results of in vivo translocation assays and genetic interaction analyses suggest a specific role for eIF5A in the cotranslational translocation of proteins into the ER, but not in the posttranslational pathway. Additionally, we observed that a block in eIF5A activation up-regulates stress-induced chaperones, which also occurs when SRP function is lost. Finally, loss of eIF5A function affects binding of the ribosome-nascent chain complex to SRP. These results link eIF5A function in translation with a role of SRP in the cell and may help explain the dual effects of eIF5A in differential and general translation.
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Affiliation(s)
- Danuza Rossi
- Department of Biological Sciences, School of Pharmaceutical Sciences, Univ Estadual Paulista, UNESP, Araraquara, SP, Brazil
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14
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Rossi D, Kuroshu R, Zanelli CF, Valentini SR. eIF5A and EF-P: two unique translation factors are now traveling the same road. WILEY INTERDISCIPLINARY REVIEWS. RNA 2014; 5:209-22. [PMID: 24402910 DOI: 10.1002/wrna.1211] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 11/01/2013] [Accepted: 11/06/2013] [Indexed: 11/09/2022]
Abstract
Translational control is extremely important in all organisms, and some of its aspects are highly conserved among all primary kingdoms, such as those related to the translation elongation step. The previously classified translation initiation factor 5A (eIF5A) and its bacterial homologue elongation factor P (EF-P) were discovered in the late 70's and have recently been the object of many studies. eIF5A and EF-P are the only cellular proteins that undergo hypusination and lysinylation, respectively, both of which are unique posttranslational modifications. Herein, we review all the important discoveries related to the biochemical and functional characterization of these factors, highlighting the implication of eIF5A in translation elongation instead of initiation. The findings that eIF5A and EF-P are important for specific cellular processes and play a role in the relief of ribosome stalling caused by specific amino acid sequences, such as those containing prolines reinforce the hypothesis that these factors are involved in specialized translation. Although there are some divergences between these unique factors, recent studies have clarified that they act similarly during protein synthesis. Further studies may reveal their precise mechanism of ribosome activity modulation as well as the mRNA targets that require eIF5A and EF-P for their proper translation.
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Affiliation(s)
- Danuza Rossi
- Department of Biological Sciences, School of Pharmaceutical Sciences, Univ Estadual Paulista (UNESP), Araraquara, SP, Brazil
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15
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Colvin SC, Maier B, Morris DL, Tersey SA, Mirmira RG. Deoxyhypusine synthase promotes differentiation and proliferation of T helper type 1 (Th1) cells in autoimmune diabetes. J Biol Chem 2013; 288:36226-35. [PMID: 24196968 DOI: 10.1074/jbc.m113.473942] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In type 1 diabetes, cytokines arising from immune cells cause islet β cell dysfunction even before overt hyperglycemia. Deoxyhypusine synthase catalyzes the crucial hypusine modification of the factor eIF5A, which promotes the translation of a subset of mRNAs involved in cytokine responses. Here, we tested the hypothesis that deoxyhypusine synthase and, secondarily, hypusinated eIF5A contribute to the pathogenesis of type 1 diabetes using the non-obese diabetic (NOD) mouse model. Pre-diabetic NOD mice that received injections of the deoxyhypusine inhibitor N1-guanyl-1,7-diaminoheptane (GC7) demonstrated significantly improved glucose tolerance, more robust insulin secretion, and reduced insulitis compared with control animals. Analysis of tissues from treated mice revealed selective reductions in diabetogenic T helper type 1 (Th1) cells in the pancreatic lymph nodes, a primary site of antigen presentation. Isolated mouse CD90.2(+) splenocytes stimulated in vitro with anti-CD3/anti-CD28 and IL-2 to mimic autoimmune T cell activation exhibited proliferation and differentiation of CD4(+) T cell subsets (Th1, Th17, and Treg), but those treated with the deoxyhypusine synthase inhibitor GC7 showed a dose-dependent block in T cell proliferation with selective reduction in Th1 cells, similar to that observed in NOD mice. Inhibition of deoxyhypusine synthase blocked post-transcriptional expression of CD25, the high affinity IL-2 receptor α chain. Our results suggest a previously unrecognized role for deoxyhypusine synthase in promoting T cell proliferation and differentiation via regulation of CD25. Inhibition of deoxyhypusine synthase may provide a strategy for reducing diabetogenic Th1 cells and preserving β cell function in type 1 diabetes.
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Affiliation(s)
- Stephanie C Colvin
- From the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research and
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16
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Evans-Molina C, Hatanaka M, Mirmira RG. Lost in translation: endoplasmic reticulum stress and the decline of β-cell health in diabetes mellitus. Diabetes Obes Metab 2013; 15 Suppl 3:159-69. [PMID: 24003933 PMCID: PMC3777692 DOI: 10.1111/dom.12163] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Accepted: 05/12/2013] [Indexed: 12/27/2022]
Abstract
Emerging data illustrate a pivotal role for activation of β-cell endoplasmic reticulum (ER) stress pathways in diabetes pathophysiology. The purpose of this review is to appraise the evidence for β-cell ER stress in human type 1 and 2 diabetes, review the molecular signalling pathways involved in the unfolded protein response and ER stress signalling, and to provide data from polyribosome profiling to illustrate the impact of ER stress on the mRNA translation response. Finally, we will discuss existing and novel therapeutic strategies that target β-cell ER stress and discuss their use in rodent and human type 1 and 2 diabetes.
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Affiliation(s)
- Carmella Evans-Molina
- Department of Medicine, Indiana University School of Medicine, Indianapolis IN, USA
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis IN, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis IN, USA
| | - Masayuki Hatanaka
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis IN, USA
| | - Raghavendra G. Mirmira
- Department of Medicine, Indiana University School of Medicine, Indianapolis IN, USA
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis IN, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis IN, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis IN, USA
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17
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Galvão FC, Rossi D, Silveira WDS, Valentini SR, Zanelli CF. The deoxyhypusine synthase mutant dys1-1 reveals the association of eIF5A and Asc1 with cell wall integrity. PLoS One 2013; 8:e60140. [PMID: 23573236 PMCID: PMC3613415 DOI: 10.1371/journal.pone.0060140] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 02/21/2013] [Indexed: 11/19/2022] Open
Abstract
The putative eukaryotic translation initiation factor 5A (eIF5A) is a highly conserved protein among archaea and eukaryotes that has recently been implicated in the elongation step of translation. eIF5A undergoes an essential and conserved posttranslational modification at a specific lysine to generate the residue hypusine. The enzymes deoxyhypusine synthase (Dys1) and deoxyhypusine hydroxylase (Lia1) catalyze this two-step modification process. Although several Saccharomyces cerevisiae eIF5A mutants have importantly contributed to the study of eIF5A function, no conditional mutant of Dys1 has been described so far. In this study, we generated and characterized the dys1-1 mutant, which showed a strong depletion of mutated Dys1 protein, resulting in more than 2-fold decrease in hypusine levels relative to the wild type. The dys1-1 mutant demonstrated a defect in total protein synthesis, a defect in polysome profile indicative of a translation elongation defect and a reduced association of eIF5A with polysomes. The growth phenotype of dys1-1 mutant is severe, growing only in the presence of 1 M sorbitol, an osmotic stabilizer. Although this phenotype is characteristic of Pkc1 cell wall integrity mutants, the sorbitol requirement from dys1-1 is not associated with cell lysis. We observed that the dys1-1 genetically interacts with the sole yeast protein kinase C (Pkc1) and Asc1, a component of the 40S ribosomal subunit. The dys1-1 mutant was synthetically lethal in combination with asc1Δ and overexpression of TIF51A (eIF5A) or DYS1 is toxic for an asc1Δ strain. Moreover, eIF5A is more associated with translating ribosomes in the absence of Asc1 in the cell. Finally, analysis of the sensitivity to cell wall-perturbing compounds revealed a more similar behavior of the dys1-1 and asc1Δ mutants in comparison with the pkc1Δ mutant. These data suggest a correlated role for eIF5A and Asc1 in coordinating the translational control of a subset of mRNAs associated with cell integrity.
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Affiliation(s)
- Fabio Carrilho Galvão
- Department of Biological Sciences, Univ Estadual Paulista – UNESP, Araraquara-Saõ Paulo, Brazil
| | - Danuza Rossi
- Department of Biological Sciences, Univ Estadual Paulista – UNESP, Araraquara-Saõ Paulo, Brazil
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18
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Dias CAO, Garcia W, Zanelli CF, Valentini SR. eIF5A dimerizes not only in vitro but also in vivo and its molecular envelope is similar to the EF-P monomer. Amino Acids 2013; 44:631-44. [PMID: 22945904 DOI: 10.1007/s00726-012-1387-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 08/01/2012] [Indexed: 11/28/2022]
Abstract
The protein eukaryotic initiation factor 5A (eIF5A) is highly conserved among archaea and eukaryotes, but not in bacteria. Bacteria have the elongation factor P (EF-P), which is structurally and functionally related to eIF5A. eIF5A is essential for cell viability and the only protein known to contain the amino acid residue hypusine, formed by post-translational modification of a specific lysine residue. Although eIF5A was initially identified as a translation initiation factor, recent studies strongly support a function for eIF5A in the elongation step of translation. However, the mode of action of eIF5A is still unknown. Here, we analyzed the oligomeric state of yeast eIF5A. First, by using size-exclusion chromatography, we showed that this protein exists as a dimer in vitro, independent of the hypusine residue or electrostatic interactions. Protein-protein interaction assays demonstrated that eIF5A can form oligomers in vitro and in vivo, in an RNA-dependent manner, but independent of the hypusine residue or the ribosome. Finally, small-angle X-ray scattering (SAXS) experiments confirmed that eIF5A behaves as a stable dimer in solution. Moreover, the molecular envelope determined from the SAXS data shows that the eIF5A dimer is L-shaped and superimposable on the tRNA(Phe) tertiary structure, analogously to the EF-P monomer.
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Affiliation(s)
- Camila Arnaldo Olhê Dias
- Department of Biological Sciences, School of Pharmaceutical Sciences, UNESP-Univ Estadual Paulista, Rodovia Araraquara-Jaú, km 01, Araraquara, SP 14801-902, Brazil
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19
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Dever TE, Green R. The elongation, termination, and recycling phases of translation in eukaryotes. Cold Spring Harb Perspect Biol 2012; 4:a013706. [PMID: 22751155 DOI: 10.1101/cshperspect.a013706] [Citation(s) in RCA: 303] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This work summarizes our current understanding of the elongation and termination/recycling phases of eukaryotic protein synthesis. We focus here on recent advances in the field. In addition to an overview of translation elongation, we discuss unique aspects of eukaryotic translation elongation including eEF1 recycling, eEF2 modification, and eEF3 and eIF5A function. Likewise, we highlight the function of the eukaryotic release factors eRF1 and eRF3 in translation termination, and the functions of ABCE1/Rli1, the Dom34:Hbs1 complex, and Ligatin (eIF2D) in ribosome recycling. Finally, we present some of the key questions in translation elongation, termination, and recycling that remain to be answered.
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Affiliation(s)
- Thomas E Dever
- Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
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20
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Role of polyamines, their analogs and transglutaminases in biological and clinical perspectives. Amino Acids 2011; 42:397-409. [DOI: 10.1007/s00726-011-1129-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 09/26/2011] [Indexed: 01/07/2023]
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