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Swathi D, Ramya L, Archana SS, Krishnappa B, Binsila BK, Selvaraju S. Identification of hub genes and their expression profiling for predicting buffalo (Bubalus bubalis) semen quality and fertility. Sci Rep 2023; 13:22126. [PMID: 38092793 PMCID: PMC10719284 DOI: 10.1038/s41598-023-48925-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 12/01/2023] [Indexed: 12/17/2023] Open
Abstract
Sperm transcriptomics provide insights into subtle differences in sperm fertilization competence. For predicting the success of complex traits like male fertility, identification of hub genes involved in various sperm functions are essential. The bulls from the transcriptome profiled samples (n = 21), were grouped into good and poor progressive motility (PM), acrosome integrity (AI), functional membrane integrity (FMI) and fertility rate (FR) groups. The up-regulated genes identified in each group were 87, 470, 1715 and 36, respectively. Gene networks were constructed using up- and down-regulated genes from each group. The top clusters from the upregulated gene networks of the PM, AI, FMI and FR groups were involved in tyrosine kinase (FDR = 1.61E-11), apoptosis (FDR = 1.65E-8), translation (FDR = 2.2E-16) and ribosomal pathway (FDR = 1.98E-21), respectively. From the clusters, the hub genes were identified and validated in a fresh set of semen samples (n = 12) using RT-qPCR. Importantly, the genes (fold change) RPL36AL (14.99) in AI, EIF5A (54.32) in FMI, and RPLP0 (8.55) and RPS28 (13.42) in FR were significantly (p < 0.05) up-regulated. The study suggests that the expression levels of MAPK3 (PM), RPL36AL + RPS27A or RPL36AL + EXT2 (AI), RPL36AL or RPS27A (FMI) and RPS18 + RPS28 (FR) are potential markers for diagnosing the semen quality and fertility status of bulls which can be used for the breeding program.
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Affiliation(s)
- Divakar Swathi
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India
- Department of Biotechnology, Jain University, Bengaluru, 560001, India
| | - Laxman Ramya
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India
| | - Santhanahalli Siddalingappa Archana
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India
| | - Balaganur Krishnappa
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India
| | - Bala Krishnan Binsila
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India
| | - Sellappan Selvaraju
- Reproductive Physiology Laboratory, Animal Physiology Division, ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bengaluru, 560030, India.
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2
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Tesina P, Ebine S, Buschauer R, Thoms M, Matsuo Y, Inada T, Beckmann R. Molecular basis of eIF5A-dependent CAT tailing in eukaryotic ribosome-associated quality control. Mol Cell 2023; 83:607-621.e4. [PMID: 36804914 DOI: 10.1016/j.molcel.2023.01.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/29/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023]
Abstract
Ribosome-associated quality control (RQC) is a conserved process degrading potentially toxic truncated nascent peptides whose malfunction underlies neurodegeneration and proteostasis decline in aging. During RQC, dissociation of stalled ribosomes is followed by elongation of the nascent peptide with alanine and threonine residues, driven by Rqc2 independently of mRNA, the small ribosomal subunit and guanosine triphosphate (GTP)-hydrolyzing factors. The resulting CAT tails (carboxy-terminal tails) and ubiquitination by Ltn1 mark nascent peptides for proteasomal degradation. Here we present ten cryogenic electron microscopy (cryo-EM) structures, revealing the mechanistic basis of individual steps of the CAT tailing cycle covering initiation, decoding, peptidyl transfer, and tRNA translocation. We discovered eIF5A as a crucial eukaryotic RQC factor enabling peptidyl transfer. Moreover, we observed dynamic behavior of RQC factors and tRNAs allowing for processivity of the CAT tailing cycle without additional energy input. Together, these results elucidate key differences as well as common principles between CAT tailing and canonical translation.
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Affiliation(s)
- Petr Tesina
- Gene Center and Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany.
| | - Shuhei Ebine
- Division of RNA and gene regulation, Institute of Medical Science, The University of Tokyo, Minato-Ku 108-8639, Japan
| | - Robert Buschauer
- Gene Center and Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Matthias Thoms
- Gene Center and Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Yoshitaka Matsuo
- Division of RNA and gene regulation, Institute of Medical Science, The University of Tokyo, Minato-Ku 108-8639, Japan
| | - Toshifumi Inada
- Division of RNA and gene regulation, Institute of Medical Science, The University of Tokyo, Minato-Ku 108-8639, Japan.
| | - Roland Beckmann
- Gene Center and Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany.
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3
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Zhang T, Zheng Y, Kuang T, Yang L, Jiang H, Wang H, Zhao Y, Han R, Che D. Arginine Regulates Zygotic Genome Activation in Porcine Embryos Under Nutrition Restriction. Front Vet Sci 2022; 9:921406. [PMID: 35812864 PMCID: PMC9260689 DOI: 10.3389/fvets.2022.921406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
Arginine has a positive effect on pre-implantation development in pigs. However, the exact mechanism by which arginine promotes embryonic development is undefined. Here, single-cell RNA sequencing technology was applied to porcine in vivo pre-implantation embryos from the zygote to morula stage, it was found that that the expression of arginine metabolism-related genes clearly changed from the 2-cell stage to the 4-cell stage, when zygotic genome activation (ZGA) occurs in porcine embryos. Further analysis showed that arginine metabolism-related genes are significantly correlated with key ZGA genes. To determine the function of arginine in porcine embryos during ZGA, the in vitro fertilization embryos were cultured in PZM-3 medium (0.12 mM arginine, Control group), a modified PZM-3 medium (0 mM arginine, Block group) and a modified PZM-3 medium supplemented with arginine (0.12 mM arginine, Block + Arg group). The results showed that the 4-cell arrest rate was significantly increased in the Block group compared to the Control group (P < 0.05). The 4-cell arrest rate in the Block + Arg group was significantly decreased than that in the Block group (P < 0.05). Meanwhile, the expression of ZGA marker genes and SIRT1 protein in 4-cell embryos was significantly decreased in the Block group compared to the Control group, and their expression was significantly increased in the Block + Arg group. In addition, we observed that the glutathione (GSH), ATP levels, and lipid droplet contents were significantly increased, and the reactive oxygen species (ROS) level was decreased in the Block + Arg group compared to the Block group. Compared with Control group, spermine content in culture medium and the mRNA expression of ornithine decarboxylase1 (ODC1) of embryos in the Block group were significantly decreased (P < 0.05), and those in the Block + Arg group were significantly increased compared with the Block group (P < 0.05). Moreover, when difluoromethylornithine (an inhibitor of ODC1) was added to the modified PZM-3 medium supplemented with arginine, the effect of arginine on ZGA was inhibited. In summary, our findings demonstrated that arginine may regulate ZGA under nutrition restriction in porcine embryos by promoting polyamine synthesis.
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Affiliation(s)
- Tianrui Zhang
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Yingying Zheng
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Tianya Kuang
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Lianyu Yang
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Hailong Jiang
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Heming Wang
- Department of Gastroenterology and Hepatology, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Institute of Liver Diseases, Shanghai, China
| | - Yicheng Zhao
- College of Clinical Medicine, Changchun University of Chinese Medicine, Changchun, China
| | - Rui Han
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
- Rui Han
| | - Dongsheng Che
- Key Laboratory of Animal Production, Product Quality and Security of Ministry of Education, Jilin Provincial Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
- *Correspondence: Dongsheng Che
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4
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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: 14] [Impact Index Per Article: 7.0] [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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5
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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: 1.7] [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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6
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Diskin C, Ryan TAJ, O'Neill LAJ. Modification of Proteins by Metabolites in Immunity. Immunity 2020; 54:19-31. [PMID: 33220233 DOI: 10.1016/j.immuni.2020.09.014] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/31/2020] [Accepted: 09/15/2020] [Indexed: 12/14/2022]
Abstract
Immunometabolism has emerged as a key focus for immunologists, with metabolic change in immune cells becoming as important a determinant for specific immune effector responses as discrete signaling pathways. A key output for these changes involves post-translational modification (PTM) of proteins by metabolites. Products of glycolysis and Krebs cycle pathways can mediate these events, as can lipids, amino acids, and polyamines. A rich and diverse set of PTMs in macrophages and T cells has been uncovered, altering phenotype and modulating immunity and inflammation in different contexts. We review the recent findings in this area and speculate whether they could be of use in the effort to develop therapeutics for immune-related diseases.
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Affiliation(s)
- C Diskin
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
| | - T A J Ryan
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
| | - L A J O'Neill
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland.
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7
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Imam S, Prathibha R, Dar P, Almotah K, Al-Khudhair A, Hasan SAM, Salim N, Jilani TN, Mirmira RG, Jaume JC. eIF5A inhibition influences T cell dynamics in the pancreatic microenvironment of the humanized mouse model of Type 1 Diabetes. Sci Rep 2019; 9:1533. [PMID: 30733517 PMCID: PMC6367423 DOI: 10.1038/s41598-018-38341-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 12/17/2018] [Indexed: 12/14/2022] Open
Abstract
We have developed a transgenic mouse model of Type 1 Diabetes (T1D) in which human GAD65 is expressed in pancreatic β-cells, and human MHC-II is expressed on antigen presenting cells. Induced GAD65 antigen presentation activates T-cells, which initiates the downstream events leading to diabetes. In our humanized mice, we have shown downregulation of eukaryotic translation initiation factor 5 A (elF5A), expressed only in actively dividing mammalian cells. In-vivo inhibition of elF5A hypusination by deoxyhypusine synthase (DHS) inhibitor "GC7" was studied; DHS inhibitor alters the pathophysiology in our mouse model by catalyzing the crucial hypusination and the rate-limiting step of elF5A activation. In our mouse model, we have shown that inhibition of eIF5A resets the pro-inflammatory bias in the pancreatic microenvironment. There was: (a) reduction of Th1/Th17 response, (b) an increase in Treg numbers, (c) debase in IL17 and IL21 cytokines levels in serum, (d) lowering of anti-GAD65 antibodies, and (e) ablation of the ER stress that improved functionality of the β-cells, but minimal effect on the cytotoxic CD8 T-cell (CTL) mediated response. Conclusively, immune modulation, in the case of T1D, may help to manipulate inflammatory responses, decreasing disease severity, and may help manage T1D in early stages of disease. Our study also demonstrates that without manipulating the CTLs mediated response extensively, it is difficult to treat T1D.
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Affiliation(s)
- Shahnawaz Imam
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA.
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA.
| | - R Prathibha
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Pervaiz Dar
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Faculty of Veterinary Sciences and Animal Husbandry, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir (SKUAST-K), Shuhama, Srinagar, 190006, Jammu and Kashmir, India
| | - Khalil Almotah
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Ahmed Al-Khudhair
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Syed Abdul-Moiz Hasan
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Nancy Salim
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Talha Naser Jilani
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Raghavendra G Mirmira
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Juan Carlos Jaume
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA.
- Center for Diabetes and Endocrine Research (CeDER), Department of Medicine, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA.
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8
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Bassani F, Romagnoli A, Cacciamani T, Amici A, Benelli D, Londei P, Märtens B, Bläsi U, La Teana A. Modification of translation factor aIF5A from Sulfolobus solfataricus. Extremophiles 2018; 22:769-780. [PMID: 30047030 PMCID: PMC6105217 DOI: 10.1007/s00792-018-1037-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 06/24/2018] [Indexed: 01/30/2023]
Abstract
Eukaryotic eIF5A and its bacterial orthologue EF-P are translation elongation factors whose task is to rescue ribosomes from stalling during the synthesis of proteins bearing particular sequences such as polyproline stretches. Both proteins are characterized by unique post-translational modifications, hypusination and lysinylation, respectively, which are essential for their function. An orthologue is present in all Archaea but its function is poorly understood. Here, we show that aIF5A of the crenarchaeum Sulfolobus solfataricus is hypusinated and forms a stable complex with deoxyhypusine synthase, the first enzyme of the hypusination pathway. The recombinant enzyme is able to modify its substrate in vitro resulting in deoxyhypusinated aIF5A. Moreover, with the aim to identify the enzyme involved in the second modification step, i.e. hypusination, a set of proteins interacting with aIF5A was identified.
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Affiliation(s)
- F Bassani
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - A Romagnoli
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - T Cacciamani
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Via Brecce Bianche, 60131, Ancona, Italy.,New York-Marche Structural Biology Center (NY-MaSBiC), Polytechnic University of Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - A Amici
- Department of Clinical Sciences, Section of Biochemistry, Polytechnic University of Marche, Via Ranieri 67, 60131, Ancona, Italy
| | - D Benelli
- Department of Cellular Biotechnologies and Haematology, Sapienza University of Rome, Via Regina Elena 324, 00161, Rome, Italy
| | - P Londei
- Department of Cellular Biotechnologies and Haematology, Sapienza University of Rome, Via Regina Elena 324, 00161, Rome, Italy
| | - B Märtens
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohrgasse 9, 1030, Vienna, Austria
| | - U Bläsi
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohrgasse 9, 1030, Vienna, Austria
| | - A La Teana
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Via Brecce Bianche, 60131, Ancona, Italy.
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9
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Muñoz-Soriano V, Domingo-Muelas A, Li T, Gamero E, Bizy A, Fariñas I, Alepuz P, Paricio N. Evolutionary conserved role of eukaryotic translation factor eIF5A in the regulation of actin-nucleating formins. Sci Rep 2017; 7:9580. [PMID: 28852021 PMCID: PMC5575014 DOI: 10.1038/s41598-017-10057-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 08/02/2017] [Indexed: 01/26/2023] Open
Abstract
Elongation factor eIF5A is required for the translation of consecutive prolines, and was shown in yeast to translate polyproline-containing Bni1, an actin-nucleating formin required for polarized growth during mating. Here we show that Drosophila eIF5A can functionally replace yeast eIF5A and is required for actin-rich cable assembly during embryonic dorsal closure (DC). Furthermore, Diaphanous, the formin involved in actin dynamics during DC, is regulated by and mediates eIF5A effects. Finally, eIF5A controls cell migration and regulates Diaphanous levels also in mammalian cells. Our results uncover an evolutionary conserved role of eIF5A regulating cytoskeleton-dependent processes through translation of formins in eukaryotes.
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Affiliation(s)
- Verónica Muñoz-Soriano
- Departamento de Genética, Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
| | - Ana Domingo-Muelas
- Departamento de Biología Celular & Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
| | - Tianlu Li
- Departamento de Bioquímica y Biología Molecular, Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
- Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), 08908, Hospitalet de Llobregat, Spain
| | - Esther Gamero
- Departamento de Bioquímica y Biología Molecular, Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
| | - Alexandra Bizy
- Departamento de Biología Celular & Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
| | - Isabel Fariñas
- Departamento de Biología Celular & Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Universidad de Valencia, 46100, Burjassot, Spain
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain
| | - Paula Alepuz
- Departamento de Bioquímica y Biología Molecular, Universidad de Valencia, 46100, Burjassot, Spain.
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain.
| | - Nuria Paricio
- Departamento de Genética, Universidad de Valencia, 46100, Burjassot, Spain.
- Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universidad de Valencia, 46100, Burjassot, Spain.
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10
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Hoque M, Park JY, Chang YJ, Luchessi AD, Cambiaghi TD, Shamanna R, Hanauske-Abel HM, Holland B, Pe'ery T, Tian B, Mathews MB. Regulation of gene expression by translation factor eIF5A: Hypusine-modified eIF5A enhances nonsense-mediated mRNA decay in human cells. ACTA ACUST UNITED AC 2017; 5:e1366294. [PMID: 29034140 DOI: 10.1080/21690731.2017.1366294] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 07/28/2017] [Accepted: 08/07/2017] [Indexed: 10/19/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) couples protein synthesis to mRNA turnover. It eliminates defective transcripts and controls the abundance of certain normal mRNAs. Our study establishes a connection between NMD and the translation factor eIF5A (eukaryotic initiation factor 5A) in human cells. eIF5A modulates the synthesis of groups of proteins (the eIF5A regulon), and undergoes a distinctive two-step post-translational modification (hypusination) catalyzed by deoxyhypusine synthase and deoxyhypusine hydroxylase. We show that expression of NMD-susceptible constructs was increased by depletion of the major eIF5A isoform, eIF5A1. NMD was also attenuated when hypusination was inhibited by RNA interference with either of the two eIF5A modifying enzymes, or by treatment with the drugs ciclopirox or deferiprone which inhibit deoxyhypusine hydroxylase. Transcriptome analysis by RNA-Seq identified human genes whose expression is coordinately regulated by eIF5A1, its modifying enzymes, and the pivotal NMD factor, Upf1. Transcripts encoding components of the translation system were highly represented, including some encoding ribosomal proteins controlled by alternative splicing coupled to NMD (AS-NMD). Our findings extend and strengthen the association of eIF5A with NMD, previously inferred in yeast, and show that hypusination is important for this function of human eIF5A. In addition, they advance drug-mediated NMD suppression as a therapeutic opportunity for nonsense-associated diseases. We propose that regulation of mRNA stability contributes to eIF5A's role in selective gene expression.
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Affiliation(s)
- Mainul Hoque
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Ji Yeon Park
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Yun-Juan Chang
- Department of Microbiology, Biochemistry & Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA.,Office of Advanced Research Computing, Rutgers University, Newark, NJ, USA
| | - Augusto D Luchessi
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA.,Laboratory of Biotechnology, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
| | - Tavane D Cambiaghi
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Raghavendra Shamanna
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Hartmut M Hanauske-Abel
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Bart Holland
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Tsafi Pe'ery
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Bin Tian
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Michael B Mathews
- Department of Biochemistry & Molecular Biology, Rutgers New Jersey Medical School, Newark, NJ, USA.,Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
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11
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Pelechano V, Alepuz P. eIF5A facilitates translation termination globally and promotes the elongation of many non polyproline-specific tripeptide sequences. Nucleic Acids Res 2017; 45:7326-7338. [PMID: 28549188 PMCID: PMC5499558 DOI: 10.1093/nar/gkx479] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 05/05/2017] [Accepted: 05/16/2017] [Indexed: 12/21/2022] Open
Abstract
eIF5A is an essential protein involved in protein synthesis, cell proliferation and animal development. High eIF5A expression is observed in many tumor types and has been linked to cancer metastasis. Recent studies have shown that eIF5A facilitates the translation elongation of stretches of consecutive prolines. Activated eIF5A binds to the empty E-site of stalled ribosomes, where it is thought to interact with the peptidyl-tRNA situated at the P-site. Here, we report a genome-wide analysis of ribosome stalling in Saccharomyces cerevisiae eIF5A depleted cells using 5Pseq. We confirm that, in the absence of eIF5A, ribosomes stall at proline stretches, and extend previous studies by identifying eIF5A-dependent ribosome pauses at termination and at >200 tripeptide motifs. We show that presence of proline, glycine and charged amino acids at the peptidyl transferase center and at the beginning of the peptide exit tunnel arrest ribosomes in eIF5A-depleted cells. Lack of eIF5A also renders ribosome accumulation at the stop codons. Our data indicate specific protein functional groups under the control of eIF5A, including ER-coupled translation and GTPases in yeast and cytoskeleton organization, collagen metabolism and cell differentiation in humans. Our results support a broad mRNA-specific role of eIF5A in translation and identify the conserved motifs that affect translation elongation from yeast to humans.
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Affiliation(s)
- Vicent Pelechano
- SciLifeLab, Department of Microbiology, Tumor and Cell Biology. Karolinska Institutet, P‐Box 1031. 171 21 Solna, Sweden
| | - Paula Alepuz
- Departamento de Bioquímica y Biología Molecular, Facultad de Biológicas, Universitat de València, C/ Dr. Moliner 50, E46100 Burjassot, Spain
- ERI-BioteMed, Facultad de Biológicas, Universitat de València, C/ Dr. Moliner 50, E46100 Burjassot, Spain
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12
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Hussain T, Tan B, Ren W, Rahu N, Kalhoro DH, Yin Y. Exploring polyamines: Functions in embryo/fetal development. ACTA ACUST UNITED AC 2016; 3:7-10. [PMID: 29767087 PMCID: PMC5941083 DOI: 10.1016/j.aninu.2016.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/11/2016] [Accepted: 12/15/2016] [Indexed: 11/28/2022]
Abstract
Polyamines such as putrescine, spermidine, spermine and agmatine are aliphatic polycationic compounds present in all living cells, and are derived from amino acids, intestinal bacteria, exfoliated enterocytes and supported from diet. Polyamines as the key compounds play essential role in cell proliferation, growth and differentiation. They also exert significant effects on embryonic development, implantation, embryonic diapause, placentation, angiogensis and fetal development. This review paper summarizes the functions of polyamines and embryo/fetus development and its regulatory mechanism which should help to provide some evidences for clinic.
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Affiliation(s)
- Tarique Hussain
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha 410125, China.,University of Chinese Academy of Sciences, Beijing 10008, China
| | - Bi'e Tan
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha 410125, China.,Hunan Collaborative Innovation Center for Utilization of Botanical Functional Ingredients, Hunan Collaborative Innovation Center of Animal Production Safety, Changsha 410000, China
| | - Wenkai Ren
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha 410125, China.,University of Chinese Academy of Sciences, Beijing 10008, China
| | - Najma Rahu
- Department of Veterinary Microbiology, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University, Tandojam 70050, Pakistan
| | - Dildar Hussain Kalhoro
- Department of Veterinary Microbiology, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University, Tandojam 70050, Pakistan
| | - Yulong Yin
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha 410125, China.,University of Chinese Academy of Sciences, Beijing 10008, China
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13
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Mandal A, Mandal S, Park MH. Global quantitative proteomics reveal up-regulation of endoplasmic reticulum stress response proteins upon depletion of eIF5A in HeLa cells. Sci Rep 2016; 6:25795. [PMID: 27180817 PMCID: PMC4867578 DOI: 10.1038/srep25795] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/20/2016] [Indexed: 11/08/2022] Open
Abstract
The eukaryotic translation factor, eIF5A, is a translation factor essential for protein synthesis, cell growth and animal development. By use of a adenoviral eIF5A shRNA, we have achieved an effective depletion of eIF5A in HeLa cells and undertook in vivo comprehensive proteomic analyses to examine the effects of eIF5A depletion on the total proteome and to identify cellular pathways influenced by eIF5A. The proteome of HeLa cells transduced with eIF5A shRNA was compared with that of scramble shRNA-transduced counterpart by the iTRAQ method. We identified 972 proteins consistently detected in three iTRAQ experiments and 104 proteins with significantly altered levels (protein ratio ≥1.5 or ≤0.66, p-value ≤0.05) at 72 h and/or 96 h of Ad-eIF5A-shRNA transduction. The altered expression levels of key pathway proteins were validated by western blotting. Integration of functional ontology with expression data of the 104 proteins revealed specific biological processes that are prominently up- or down-regulated. Heatmap analysis and Cytoscape visualization of biological networks identified protein folding as the major cellular process affected by depletion of eIF5A. Our unbiased, quantitative, proteomic data demonstrate that the depletion of eIF5A leads to endoplasmic reticulum stress, an unfolded protein response and up-regulation of chaperone expression in HeLa cells.
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Affiliation(s)
- Ajeet Mandal
- Molecular and Cellular Biochemistry Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bldg.30 Rm. 3A300, Bethesda, MD 20892, USA
| | - Swati Mandal
- Molecular and Cellular Biochemistry Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bldg.30 Rm. 3A300, Bethesda, MD 20892, USA
| | - Myung Hee Park
- Molecular and Cellular Biochemistry Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bldg.30 Rm. 3A300, Bethesda, MD 20892, USA
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14
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Ermert AL, Mailliet K, Hughes J. Holophytochrome-Interacting Proteins in Physcomitrella: Putative Actors in Phytochrome Cytoplasmic Signaling. FRONTIERS IN PLANT SCIENCE 2016; 7:613. [PMID: 27242820 PMCID: PMC4867686 DOI: 10.3389/fpls.2016.00613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 04/21/2016] [Indexed: 05/26/2023]
Abstract
Phytochromes are the principle photoreceptors in light-regulated plant development, primarily acting via translocation of the light-activated photoreceptor into the nucleus and subsequent gene regulation. However, several independent lines of evidence indicate unambiguously that an additional cytoplasmic signaling mechanism must exist. Directional responses in filament tip cells of the moss Physcomitrella patens are steered by phy4 which has been shown to interact physically with the blue light receptor phototropin at the plasma membrane. This complex might perceive and transduce vectorial information leading to cytoskeleton reorganization and finally a directional growth response. We developed yeast two-hybrid procedures using photochemically functional, full-length phy4 as bait in Physcomitrella cDNA library screens and growth assays under different light conditions, revealing Pfr-dependent interactions possibly associated with phytochrome cytoplasmic signaling. Candidate proteins were then expressed in planta with fluorescent protein tags to determine their intracellular localization in darkness and red light. Of 14 candidates, 12 were confirmed to interact with phy4 in planta using bimolecular fluorescence complementation. We also used database information to study their expression patterns relative to those of phy4. We discuss the likely functional characteristics of these holophytochrome-interacting proteins (HIP's) and their possible roles in signaling.
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15
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Martinez-Rocha AL, Woriedh M, Chemnitz J, Willingmann P, Kröger C, Hadeler B, Hauber J, Schäfer W. Posttranslational hypusination of the eukaryotic translation initiation factor-5A regulates Fusarium graminearum virulence. Sci Rep 2016; 6:24698. [PMID: 27098988 PMCID: PMC4838825 DOI: 10.1038/srep24698] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 04/04/2016] [Indexed: 11/14/2022] Open
Abstract
Activation of eukaryotic translation initiation factor eIF5A requires a posttranslational modification, forming the unique amino acid hypusine. This activation is mediated by two enzymes, deoxyhypusine synthase, DHS, and deoxyhypusine hydroxylase, DOHH. The impact of this enzymatic complex on the life cycle of a fungal pathogen is unknown. Plant pathogenic ascomycetes possess a single copy of the eIF5A activated by hypusination. We evaluated the importance of imbalances in eIF5A hypusination in Fusarium graminearum, a devastating fungal pathogen of cereals. Overexpression of DHS leads to increased virulence in wheat, elevated production of the mycotoxin deoxynivalenol, more infection structures, faster wheat tissue invasion in plants and increases vegetatively produced conidia. In contrast, overexpression of DOHH completely prevents infection structure formation, pathogenicity in wheat and maize, leads to overproduction of ROS, reduced DON production and increased sexual reproduction. Simultaneous overexpression of both genes restores wild type-like phenotypes. Analysis of eIF5A posttranslational modification displayed strongly increased hypusinated eIF5A in DOHH overexpression mutant in comparison to wild type, and the DHS overexpression mutants. These are the first results pointing to different functions of differently modified eIF5A.
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Affiliation(s)
- Ana Lilia Martinez-Rocha
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
| | - Mayada Woriedh
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
| | - Jan Chemnitz
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Department Antiviral Strategies, Hamburg, D-20251, Germany
| | - Peter Willingmann
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
| | - Cathrin Kröger
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
| | - Birgit Hadeler
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
| | - Joachim Hauber
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Department Antiviral Strategies, Hamburg, D-20251, Germany
- German Center for Infection Research (DZIF), partner site Hamburg, Hamburg, Germany
| | - Wilhelm Schäfer
- University of Hamburg, Biocenter Klein Flottbek, Molecular Phytopathology and Genetics, Hamburg, D-22609, Germany
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16
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Nguyen S, Leija C, Kinch L, Regmi S, Li Q, Grishin NV, Phillips MA. Deoxyhypusine Modification of Eukaryotic Translation Initiation Factor 5A (eIF5A) Is Essential for Trypanosoma brucei Growth and for Expression of Polyprolyl-containing Proteins. J Biol Chem 2015; 290:19987-98. [PMID: 26082486 PMCID: PMC4528157 DOI: 10.1074/jbc.m115.656785] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 05/18/2015] [Indexed: 11/06/2022] Open
Abstract
The eukaryotic protozoan parasite Trypanosoma brucei is the causative agent of human African trypanosomiasis. Polyamine biosynthesis is essential in T. brucei, and the polyamine spermidine is required for synthesis of a novel cofactor called trypanothione and for deoxyhypusine modification of eukaryotic translation initiation factor 5A (eIF5A). eIF5A promotes translation of proteins containing polyprolyl tracts in mammals and yeast. To evaluate the function of eIF5A in T. brucei, we used RNA interference (RNAi) to knock down eIF5A levels and found that it is essential for T. brucei growth. The RNAi-induced growth defect was complemented by expression of wild-type human eIF5A but not by a Lys-50 mutant that blocks modification by deoxyhypusine. Bioinformatics analysis showed that 15% of the T. brucei proteome contains 3 or more consecutive prolines and that actin-related proteins and cysteine proteases were highly enriched in the group. Steady-state protein levels of representative proteins containing 9 consecutive prolines that are involved in actin assembly (formin and CAP/Srv2p) were significantly reduced by knockdown of eIF5A. Several T. brucei polyprolyl proteins are involved in flagellar assembly. Knockdown of TbeIF5A led to abnormal cell morphologies and detached flagella, suggesting that eIF5A is important for translation of proteins needed for these processes. Potential specialized functions for eIF5A in T. brucei in translation of variable surface glycoproteins were also uncovered. Inhibitors of deoxyhypusination would be expected to cause a pleomorphic effect on multiple cell processes, suggesting that deoxyhypusine/hypusine biosynthesis could be a promising drug target in not just T. brucei but in other eukaryotic pathogens.
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MESH Headings
- Amino Acid Sequence
- Animals
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Flagella/genetics
- Flagella/metabolism
- Flagella/ultrastructure
- Gene Knockdown Techniques
- Humans
- Lysine/analogs & derivatives
- Lysine/metabolism
- Microfilament Proteins/genetics
- Microfilament Proteins/metabolism
- Molecular Sequence Data
- Peptide Initiation Factors/antagonists & inhibitors
- Peptide Initiation Factors/genetics
- Peptide Initiation Factors/metabolism
- Peptides/metabolism
- Protein Processing, Post-Translational
- Proteome/genetics
- Proteome/metabolism
- Protozoan Proteins/antagonists & inhibitors
- Protozoan Proteins/genetics
- Protozoan Proteins/metabolism
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Protozoan/antagonists & inhibitors
- RNA, Protozoan/genetics
- RNA, Protozoan/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- RNA-Binding Proteins/antagonists & inhibitors
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Alignment
- Sequence Homology, Amino Acid
- Trypanosoma brucei brucei/genetics
- Trypanosoma brucei brucei/metabolism
- Trypanosoma brucei brucei/ultrastructure
- Eukaryotic Translation Initiation Factor 5A
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Affiliation(s)
| | | | | | | | - Qiong Li
- From the Departments of Pharmacology and
| | - Nick V Grishin
- Biophysics and Biochemistry and Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9041
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17
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Mandal A, Mandal S, Park MH. Genome-wide analyses and functional classification of proline repeat-rich proteins: potential role of eIF5A in eukaryotic evolution. PLoS One 2014; 9:e111800. [PMID: 25364902 PMCID: PMC4218817 DOI: 10.1371/journal.pone.0111800] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 10/06/2014] [Indexed: 12/16/2022] Open
Abstract
The eukaryotic translation factor, eIF5A has been recently reported as a sequence-specific elongation factor that facilitates peptide bond formation at consecutive prolines in Saccharomyces cerevisiae, as its ortholog elongation factor P (EF-P) does in bacteria. We have searched the genome databases of 35 representative organisms from six kingdoms of life for PPP (Pro-Pro-Pro) and/or PPG (Pro-Pro-Gly)-encoding genes whose expression is expected to depend on eIF5A. We have made detailed analyses of proteome data of 5 selected species, Escherichia coli, Saccharomyces cerevisiae, Drosophila melanogaster, Mus musculus and Homo sapiens. The PPP and PPG motifs are low in the prokaryotic proteomes. However, their frequencies markedly increase with the biological complexity of eukaryotic organisms, and are higher in newly derived proteins than in those orthologous proteins commonly shared in all species. Ontology classifications of S. cerevisiae and human genes encoding the highest level of polyprolines reveal their strong association with several specific biological processes, including actin/cytoskeletal associated functions, RNA splicing/turnover, DNA binding/transcription and cell signaling. Previously reported phenotypic defects in actin polarity and mRNA decay of eIF5A mutant strains are consistent with the proposed role for eIF5A in the translation of the polyproline-containing proteins. Of all the amino acid tandem repeats (≥3 amino acids), only the proline repeat frequency correlates with functional complexity of the five organisms examined. Taken together, these findings suggest the importance of proline repeat-rich proteins and a potential role for eIF5A and its hypusine modification pathway in the course of eukaryotic evolution.
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Affiliation(s)
- Ajeet Mandal
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Swati Mandal
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland, United States of America
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18
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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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19
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Li T, Belda-Palazón B, Ferrando A, Alepuz P. Fertility and polarized cell growth depends on eIF5A for translation of polyproline-rich formins in Saccharomyces cerevisiae. Genetics 2014; 197:1191-200. [PMID: 24923804 PMCID: PMC4125393 DOI: 10.1534/genetics.114.166926] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 06/05/2014] [Indexed: 01/15/2023] Open
Abstract
eIF5A is an essential and evolutionary conserved translation elongation factor, which has recently been proposed to be required for the translation of proteins with consecutive prolines. The binding of eIF5A to ribosomes occurs upon its activation by hypusination, a modification that requires spermidine, an essential factor for mammalian fertility that also promotes yeast mating. We show that in response to pheromone, hypusinated eIF5A is required for shmoo formation, localization of polarisome components, induction of cell fusion proteins, and actin assembly in yeast. We also show that eIF5A is required for the translation of Bni1, a proline-rich formin involved in polarized growth during shmoo formation. Our data indicate that translation of the polyproline motifs in Bni1 is eIF5A dependent and this translation dependency is lost upon deletion of the polyprolines. Moreover, an exogenous increase in Bni1 protein levels partially restores the defect in shmoo formation seen in eIF5A mutants. Overall, our results identify eIF5A as a novel and essential regulator of yeast mating through formin translation. Since eIF5A and polyproline formins are conserved across species, our results also suggest that eIF5A-dependent translation of formins could regulate polarized growth in such processes as fertility and cancer in higher eukaryotes.
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Affiliation(s)
- Tianlu Li
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, E-46100 Burjassot, Valencia, Spain
| | - Borja Belda-Palazón
- Instituto de Biología Molecular y Celular de Plantas, Centro Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Alejandro Ferrando
- Instituto de Biología Molecular y Celular de Plantas, Centro Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Paula Alepuz
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, E-46100 Burjassot, Valencia, Spain
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20
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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: 4.5] [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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21
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Chung J, Rocha AA, Tonelli RR, Castilho BA, Schenkman S. Eukaryotic initiation factor 5A dephosphorylation is required for translational arrest in stationary phase cells. Biochem J 2013; 451:257-67. [PMID: 23368777 DOI: 10.1042/bj20121553] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The protein known as eIF5A (eukaryotic initiation factor 5A) has an elusive role in translation. It has a unique and essential hypusine modification at a conserved lysine residue in most eukaryotes. In addition, this protein is modified by phosphorylation with unknown functions. In the present study we show that a phosphorylated state of eIF5A predominates in exponentially growing Trypanosoma cruzi cells, and extensive dephosphorylation occurs in cells in stationary phase. Phosphorylation occurs mainly at Ser(2), as shown in yeast eIF5A. In addition, a novel phosphorylation site was identified at Tyr(21). In exponential cells, T. cruzi eIF5A is partially associated with polysomes, compatible with a proposed function as an elongation factor, and becomes relatively enriched in polysomal fractions in stationary phase. Overexpression of the wild-type eIF5A, or eIF5A with Ser(2) replaced by an aspartate residue, but not by alanine, increases the rate of cell proliferation and protein synthesis. However, the presence of an aspartate residue instead of Ser(2) is toxic for cells reaching the stationary phase, which show a less-pronounced protein synthesis arrest and a decreased amount of eIF5A in dense fractions of sucrose gradients. We conclude that eIF5A phosphorylation and dephosphorylation cycles regulate translation according to the growth conditions.
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Affiliation(s)
- Janete Chung
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Pedro de Toledo 669 L6A, São Paulo, S.P. 04039-032, Brazil
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22
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Pal P, Kanaujiya JK, Lochab S, Tripathi SB, Sanyal S, Behre G, Trivedi AK. Proteomic analysis of rosiglitazone and guggulsterone treated 3T3-L1 preadipocytes. Mol Cell Biochem 2012; 376:81-93. [PMID: 23275126 DOI: 10.1007/s11010-012-1551-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 12/14/2012] [Indexed: 01/16/2023]
Abstract
Adipogenesis is the differentiation of preadipocytes to adipocytes which is marked by the accumulation of lipid droplets. Adipogenic differentiation of 3T3-L1 cells is achieved by exposing the cells to Insulin, Dexamethasone and IBMX for 5-7 days. Thiazolidinedione drugs, like rosiglitazone are potent insulin sensitizing agents and have been shown to enhance lipid droplet formation in 3T3-L1 cells, a model cell line for preadipocyte differentiation. Guggulsterone is a natural drug extracted from the gum resin of tree Commiphora mukul. Guggulsterone has been shown to inhibit adipogenesis and induce apoptosis in 3T3-L1 cells. In this study we treated the 3T3-L1 preadipocytes with rosiglitazone and guggulsterone and assessed the protein expression profile using 2D gel electrophoresis-based proteomics to find out differential target proteins of these drugs. The proteins that were identified upon rosiglitazone treatment generally regulate cell proliferation and/or exhibit anti-inflammatory effect which strengthens its differentiation-inducing property. Guggulsterone treatment resulted in the identification of the apoptosis-inducing proteins to be up regulated which rightly is in agreement with the apoptosis-inducing property of guggulsterone in 3T3-L1 cells. Some of the proteins identified in our proteomic screen such as Galectin1, AnnexinA2 & TCTP were further confirmed by Real Time qPCR. Thus, the present study provides a better outlook of proteins being differentially regulated/expressed upon treatment with rosiglitazone and guggulsterone. The detailed study of the differentially expressed proteins identified in this proteomic screen may further provide the better molecular insight into the mode of action of these anti-diabetic drugs rosiglitazone and guggulsterone.
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Affiliation(s)
- Pooja Pal
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute, Jankipuram Extension, Lucknow, UP, India
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23
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The molecular basis of wound healing processes induced by lithospermi radix: a proteomics and biochemical analysis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:508972. [PMID: 23024692 PMCID: PMC3457683 DOI: 10.1155/2012/508972] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Revised: 07/16/2012] [Accepted: 07/18/2012] [Indexed: 12/20/2022]
Abstract
Lithospermi Radix (LR) is an effective traditional Chinese herb in various types of wound healing; however, its mechanism of action remains unknown. A biochemical and proteomic platform was generated to explore the biological phenomena associated with LR and its active component shikonin. We found that both LR ethanol extracts and shikonin are able to promote cell proliferation by up to 25%. The results of proteomic analysis revealed that twenty-two differentially expressed proteins could be identified when fibroblast cells were treated with LR or shikonin. The functions of those proteins are associated with antioxidant activity, antiapoptosis activity, the regulation of cell mobility, the secretion of collagen, the removal of abnormal proteins, and the promotion of cell proliferation, indicating that the efficacy of LR in wound healing may be derived from a synergistic effect on a number of factors induced by the herbal medicine. Furthermore, an animal model confirmed that LR is able to accelerate wound healing on the flank back of the SD rats. Together these findings help to pinpoint the molecular basis of wound healing process induced by LR.
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24
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Preukschas M, Hagel C, Schulte A, Weber K, Lamszus K, Sievert H, Pällmann N, Bokemeyer C, Hauber J, Braig M, Balabanov S. Expression of eukaryotic initiation factor 5A and hypusine forming enzymes in glioblastoma patient samples: implications for new targeted therapies. PLoS One 2012; 7:e43468. [PMID: 22927971 PMCID: PMC3424167 DOI: 10.1371/journal.pone.0043468] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 07/20/2012] [Indexed: 12/23/2022] Open
Abstract
Glioblastomas are highly aggressive brain tumors of adults with poor clinical outcome. Despite a broad range of new and more specific treatment strategies, therapy of glioblastomas remains challenging and tumors relapse in all cases. Recent work demonstrated that the posttranslational hypusine modification of the eukaryotic initiation factor 5A (eIF-5A) is a crucial regulator of cell proliferation, differentiation and an important factor in tumor formation, progression and maintenance. Here we report that eIF-5A as well as the hypusine-forming enzymes deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH) are highly overexpressed in glioblastoma patient samples. Importantly, targeting eIF-5A and its hypusine modification with GC7, a specific DHS-inhibitor, showed a strong antiproliferative effect in glioblastoma cell lines in vitro, while normal human astrocytes were not affected. Furthermore, we identified p53 dependent premature senescence, a permanent cell cycle arrest, as the primary outcome in U87-MG cells after treatment with GC7. Strikingly, combined treatment with clinically relevant alkylating agents and GC7 had an additive antiproliferative effect in glioblastoma cell lines. In addition, stable knockdown of eIF-5A and DHS by short hairpin RNA (shRNA) could mimic the antiproliferative effects of GC7. These findings suggest that pharmacological inhibition of eIF-5A may represent a novel concept to treat glioblastomas and may help to substantially improve the clinical course of this tumor entity.
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Affiliation(s)
- Michael Preukschas
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Hagel
- Department of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexander Schulte
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kristoffer Weber
- Research Department Cell and Gene Therapy, Clinic for Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katrin Lamszus
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Henning Sievert
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nora Pällmann
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Carsten Bokemeyer
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Joachim Hauber
- Heinrich-Pette-Institute – Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Melanie Braig
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan Balabanov
- Department of Oncology, Haematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald-Tumorzentrum, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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25
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Wang L, Xu C, Wang C, Wang Y. Characterization of a eukaryotic translation initiation factor 5A homolog from Tamarix androssowii involved in plant abiotic stress tolerance. BMC PLANT BIOLOGY 2012; 12:118. [PMID: 22834699 PMCID: PMC3479025 DOI: 10.1186/1471-2229-12-118] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 07/09/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND The eukaryotic translation initiation factor 5A (eIF5A) promotes formation of the first peptide bond at the onset of protein synthesis. However, the function of eIF5A in plants is not well understood. RESULTS In this study, we characterized the function of eIF5A (TaeIF5A1) from Tamarix androssowii. The promoter of TaeIF5A1 with 1,486 bp in length was isolated, and the cis-elements in the promoter were identified. A WRKY (TaWRKY) and RAV (TaRAV) protein can specifically bind to a W-box motif in the promoter of TaeIF5A1 and activate the expression of TaeIF5A1. Furthermore, TaeIF5A1, TaWRKY and TaRAV share very similar expression pattern and are all stress-responsive gene that functions in the abscisic acid (ABA) signaling pathway, indicating that they are components of a single regulatory pathway. Transgenic yeast and poplar expressing TaeIF5A1 showed elevated protein levels combined with improved abiotic stresses tolerance. Furthermore, TaeIF5A1-transformed plants exhibited enhanced superoxide dismutase (SOD) and peroxidase (POD) activities, lower electrolyte leakage and higher chlorophyll content under salt stress. CONCLUSIONS These results suggested that TaeIF5A1 is involved in abiotic stress tolerance, and is likely regulated by transcription factors TaWRKY and TaRAV both of which can bind to the W-box motif. In addition, TaeIF5A1 may mediate stress tolerance by increasing protein synthesis, enhancing ROS scavenging by improving SOD and POD activities, and preventing chlorophyll loss and membrane damage. Therefore, eIF5A may play an important role in plant adaptation to changing environmental conditions.
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MESH Headings
- Abscisic Acid/metabolism
- Abscisic Acid/pharmacology
- Adaptation, Physiological
- Cell Membrane/genetics
- Cell Membrane/metabolism
- Chlorophyll/genetics
- Chlorophyll/metabolism
- Cloning, Molecular
- Gene Expression Regulation, Plant
- Genetic Vectors
- Peptide Initiation Factors/genetics
- Peptide Initiation Factors/metabolism
- Peroxidase/genetics
- Peroxidase/metabolism
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/metabolism
- Plants, Genetically Modified/physiology
- Promoter Regions, Genetic
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Regulatory Sequences, Nucleic Acid
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/metabolism
- Salt-Tolerant Plants/genetics
- Salt-Tolerant Plants/metabolism
- Salt-Tolerant Plants/physiology
- Signal Transduction
- Sodium Chloride/pharmacology
- Solubility
- Stress, Physiological
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Tamaricaceae/genetics
- Tamaricaceae/metabolism
- Tamaricaceae/physiology
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transformation, Genetic
- Eukaryotic Translation Initiation Factor 5A
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Affiliation(s)
- Liuqiang Wang
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), 26 Hexing Road, Harbin, China
| | - Chenxi Xu
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), 26 Hexing Road, Harbin, China
| | - Chao Wang
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), 26 Hexing Road, Harbin, China
| | - Yucheng Wang
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), 26 Hexing Road, Harbin, China
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26
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Nishimura K, Lee SB, Park JH, Park MH. Essential role of eIF5A-1 and deoxyhypusine synthase in mouse embryonic development. Amino Acids 2012; 42:703-10. [PMID: 21850436 PMCID: PMC3220921 DOI: 10.1007/s00726-011-0986-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 05/10/2011] [Indexed: 10/17/2022]
Abstract
The eukaryotic initiation factor 5A (eIF5A) contains a polyamine-derived amino acid, hypusine [N(ε)-(4-amino-2-hydroxybutyl)lysine]. Hypusine is formed post-translationally by the addition of the 4-aminobutyl moiety from the polyamine spermidine to a specific lysine residue, catalyzed by deoxyhypusine synthase (DHPS), and subsequent hydroxylation by deoxyhypusine hydroxylase (DOHH). The eIF5A precursor protein and both of its modifying enzymes are highly conserved, suggesting a vital cellular function for eIF5A and its hypusine modification. To address the functions of eIF5A and the first modification enzyme, DHPS, in mammalian development, we knocked out the Eif5a or the Dhps gene in mice. Eif5a heterozygous knockout mice and Dhps heterozygous knockout mice were viable and fertile. However, homozygous Eif5a1 (gt/gt) embryos and Dhps (gt/gt) embryos died early in embryonic development, between E3.5 and E7.5. Upon transfer to in vitro culture, homozygous Eif5a (gt/gt) or Dhps (gt/gt) blastocysts at E3.5 showed growth defects when compared to heterozygous or wild type blastocysts. Thus, the knockout of either the eIF5A-1 gene (Eif5a) or of the deoxyhypusine synthase gene (Dhps) caused early embryonic lethality in mice, indicating the essential nature of both eIF5A-1 and deoxyhypusine synthase in mammalian development.
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Affiliation(s)
| | - Seung Bum Lee
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Bldg 30, Room 211, MD 20892-4340, USA
| | - Jong Hwan Park
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Bldg 30, Room 211, MD 20892-4340, USA
| | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Bldg 30, Room 211, MD 20892-4340, USA
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27
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Abstract
Elongation factor P (EF-P) is posttranslationally modified at a conserved lysyl residue by the coordinated action of two enzymes, PoxA and YjeK. We have previously established the importance of this modification in Salmonella stress resistance. Here we report that, like poxA and yjeK mutants, Salmonella strains lacking EF-P display increased susceptibility to hypoosmotic conditions, antibiotics, and detergents and enhanced resistance to the compound S-nitrosoglutathione. The susceptibility phenotypes are largely explained by the enhanced membrane permeability of the efp mutant, which exhibits increased uptake of the hydrophobic dye 1-N-phenylnaphthylamine (NPN). Analysis of the membrane proteomes of wild-type and efp mutant Salmonella strains reveals few changes, including the prominent overexpression of a single porin, KdgM, in the efp mutant outer membrane. Removal of KdgM in the efp mutant background ameliorates the detergent, antibiotic, and osmosensitivity phenotypes and restores wild-type permeability to NPN. Our data support a role for EF-P in the translational regulation of a limited number of proteins that, when perturbed, renders the cell susceptible to stress by the adventitious overexpression of an outer membrane porin.
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28
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Templin AT, Maier B, Nishiki Y, Tersey SA, Mirmira RG. Deoxyhypusine synthase haploinsufficiency attenuates acute cytokine signaling. Cell Cycle 2011; 10:1043-9. [PMID: 21389784 PMCID: PMC3100881 DOI: 10.4161/cc.10.7.15206] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 02/17/2011] [Indexed: 11/19/2022] Open
Abstract
Deoxyhypusine synthase (DHS) catalyzes the post-translational formation of the amino acid hypusine. Hypusine is unique to the eukaryotic translational initiation factor 5A (eIF5A), and is required for its functions in mRNA shuttling, translational elongation, and stress granule formation. In recent studies, we showed that DHS promotes cytokine and ER stress signaling in the islet β cell and thereby contributes to its dysfunction in the setting of diabetes mellitus. Here, we review the evidence supporting a role for DHS (and hypusinated eIF5A) in cellular stress responses, and provide new data on the phenotype of DHS knockout mice. We show that homozygous knockout mice are embryonic lethal, but heterozygous knockout mice appear normal with no evidence of growth or metabolic deficiencies. Mouse embryonic fibroblasts from heterozygous knockout mice attenuate acute cytokine signaling, as evidenced by reduced production of inducible nitric oxide synthase, but show no statistically significant defects in proliferation or cell cycle progression. Our data are discussed with respect to the utility of sub-maximal inhibition of DHS in the setting of inflammatory states, such as diabetes mellitus.
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Affiliation(s)
- Andrew T Templin
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN USA
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29
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Ethanol-induced changes in the expression of proteins related to neurotransmission and metabolism in different regions of the rat brain. Pharmacol Biochem Behav 2011; 99:428-36. [PMID: 21397625 DOI: 10.1016/j.pbb.2011.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 03/01/2011] [Accepted: 03/04/2011] [Indexed: 01/06/2023]
Abstract
Despite extensive description of the damaging effects of chronic alcohol exposure on brain structure, mechanistic explanations for the observed changes are just emerging. To investigate regional brain changes in protein expression levels following chronic ethanol treatment, one rat per sibling pair of male Wistar rats was exposed to intermittent (14 h/day) vaporized ethanol, the other to air for 26 weeks. At the end of 24 weeks of vapor exposure, the ethanol group had blood ethanol levels averaging 450 mg%, had not experienced a protracted (> 16 h) withdrawal from ethanol, and revealed only mild evidence of hepatic steatosis. Extracted brains were micro-dissected to isolate the prefrontal cortex (PFC), dorsal striatum (STR), corpus callosum genu (CCg), CC body (CCb), anterior vermis (AV), and anterior dorsal lateral cerebellum (ADLC) for protein analysis with two-dimensional gel electrophoresis. Expression levels for 54 protein spots were significantly different between the ethanol- and air-treated groups. Of these 54 proteins, tandem mass spectroscopy successfully identified 39 unique proteins, the levels of which were modified by ethanol treatment: 13 in the PFC, 7 in the STR, 2 in the CCg, 7 in the CCb, 7 in the AV, and 5 in the ADLC. The functions of the proteins altered by chronic ethanol exposure were predominantly associated with neurotransmitter systems in the PFC and cell metabolism in the STR. Stress response proteins were elevated only in the PFC, AV, and ADLC perhaps supporting a role for frontocerebellar circuitry disruption in alcoholism. Of the remaining proteins, some had functions associated with cytoskeletal physiology (e.g., in the CCb) and others with transcription/translation (e.g., in the ADLC). Considered collectively, all but 4 of the 39 proteins identified in the present study have been previously identified in ethanol gene- and/or protein-expression studies lending support for their role in ethanol-related brain alterations.
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30
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Hwang HH, Moon PG, Lee JE, Kim JG, Lee W, Ryu SH, Baek MC. Identification of the target proteins of rosiglitazone in 3T3-L1 adipocytes through proteomic analysis of cytosolic and secreted proteins. Mol Cells 2011; 31:239-46. [PMID: 21347706 PMCID: PMC3932691 DOI: 10.1007/s10059-011-0026-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 11/27/2010] [Accepted: 12/06/2010] [Indexed: 12/13/2022] Open
Abstract
Rosiglitazone, one of the thiazolidinedione (TZD), is an oral antidiabetic drug that activates a gamma isoform of peroxisome proliferator-activated receptor (PPARγ). To identify target proteins induced by rosiglitazone in adipocytes, we first performed simultaneous in-depth proteomic profiling of cytosolic proteins and secreted proteins (secretome) from 3T3-L1 adipocytes using a label-free quantification method with nano-UPLC MS/MS. In total, we identified 646 proteins from 3T3-L1 adipocytes, of which 172 and 162 proteins were upregulated and downregulated >1.5-fold, respectively, in rosiglitazone-treated cells, as compared to controls. Some differentially expressed proteins in particular, including fatty acid translocase (FAT)/CD36, fatty acid binding protein, lipoprotein lipase, acetyl CoA acyltransferase, carnitine O-palmitoyltransferase 2, sterol carrier protein, adiponectin, and phosphoenolpyruvate carboxykinase could explain the current action mechanism of TZDs. Furthermore, this study is the first to report on two potential target proteins of rosiglitazone, such as adenomatosis polyposis coli 2 (APC2), and eukaryotic translation initiation factor 5A-1 (eIF5A) related to apoptosis and cell division. Our data clearly suggest that in-depth proteomic approaches using cytosolic and secreted proteins are important and necessary for identification of drug targets at the protein level.
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Affiliation(s)
- Hyun-Ho Hwang
- Department of Molecular Medicine, Kyungpook National University, Daegu 700-422, Korea
- Cell and Matrix Biology Research Institute, Kyungpook National University, Daegu 700-422, Korea
| | - Pyong-Gon Moon
- Department of Molecular Medicine, Kyungpook National University, Daegu 700-422, Korea
- Cell and Matrix Biology Research Institute, Kyungpook National University, Daegu 700-422, Korea
| | - Jeong-Eun Lee
- Department of Molecular Medicine, Kyungpook National University, Daegu 700-422, Korea
- Cell and Matrix Biology Research Institute, Kyungpook National University, Daegu 700-422, Korea
| | - Jung-Guk Kim
- Department of Internal Medicine, Kyungpook National University Hospital, Daegu, 700-721, Korea
| | - Wan Lee
- College of Medicine, Dongguk University, Gyeongju 780-714, Korea
| | - Sung-Ho Ryu
- Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Moon-Chang Baek
- Department of Molecular Medicine, Kyungpook National University, Daegu 700-422, Korea
- Cell and Matrix Biology Research Institute, Kyungpook National University, Daegu 700-422, Korea
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31
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Park JH, Dias CAO, Lee SB, Valentini SR, Sokabe M, Fraser CS, Park MH. Production of active recombinant eIF5A: reconstitution in E.coli of eukaryotic hypusine modification of eIF5A by its coexpression with modifying enzymes. Protein Eng Des Sel 2011; 24:301-9. [PMID: 21131325 PMCID: PMC3038461 DOI: 10.1093/protein/gzq110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 11/03/2010] [Accepted: 11/03/2010] [Indexed: 11/12/2022] Open
Abstract
Eukaryotic translation initiation factor 5A (eIF5A) is the only cellular protein that contains the polyamine-modified lysine, hypusine [N(ε)-(4-amino-2-hydroxybutyl)lysine]. Hypusine occurs only in eukaryotes and certain archaea, but not in eubacteria. It is formed post-translationally by two consecutive enzymatic reactions catalyzed by deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH). Hypusine modification is essential for the activity of eIF5A and for eukaryotic cell proliferation. eIF5A binds to the ribosome and stimulates translation in a hypusine-dependent manner, but its mode of action in translation is not well understood. Since quantities of highly pure hypusine-modified eIF5A is desired for structural studies as well as for determination of its binding sites on the ribosome, we have used a polycistronic vector, pST39, to express eIF5A alone, or to co-express human eIF5A-1 with DHS or with both DHS and DOHH in Escherichia coli cells, to engineer recombinant proteins, unmodified eIF5A, deoxyhypusine- or hypusine-modified eIF5A. We have accomplished production of three different forms of recombinant eIF5A in high quantity and purity. The recombinant hypusine-modified eIF5A was as active in methionyl-puromycin synthesis as the native, eIF5A (hypusine form) purified from mammalian tissue. The recombinant eIF5A proteins will be useful tools in future structure/function and the mechanism studies in translation.
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Affiliation(s)
- Jong Hwan Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4340, USA
| | - Camila A. O. Dias
- Department of Biological Sciences, School of Pharmaceutical Sciences, University of Estadual Paulista – UNESP, Bldg 30 Rm 211, Araraquara, SP, Brazil
| | - Seung Bum Lee
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4340, USA
| | - Sandro R. Valentini
- Department of Biological Sciences, School of Pharmaceutical Sciences, University of Estadual Paulista – UNESP, Bldg 30 Rm 211, Araraquara, SP, Brazil
| | | | - Christopher S. Fraser
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4340, USA
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32
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Robbins RD, Tersey SA, Ogihara T, Gupta D, Farb TB, Ficorilli J, Bokvist K, Maier B, Mirmira RG. Inhibition of deoxyhypusine synthase enhances islet {beta} cell function and survival in the setting of endoplasmic reticulum stress and type 2 diabetes. J Biol Chem 2010; 285:39943-52. [PMID: 20956533 PMCID: PMC3000976 DOI: 10.1074/jbc.m110.170142] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 10/04/2010] [Indexed: 01/09/2023] Open
Abstract
Islet β cell dysfunction resulting from inflammation, ER stress, and oxidative stress is a key determinant in the progression from insulin resistance to type 2 diabetes mellitus. It was recently shown that the enzyme deoxyhypusine synthase (DHS) promotes early cytokine-induced inflammation in the β cell. DHS catalyzes the conversion of lysine to hypusine, an amino acid that is unique to the translational elongation factor eIF5A. Here, we sought to determine whether DHS activity contributes to β cell dysfunction in models of type 2 diabetes in mice and β cell lines. A 2-week treatment of obese diabetic C57BLKS/J-db/db mice with the DHS inhibitor GC7 resulted in improved glucose tolerance, increased insulin release, and enhanced β cell mass. Thapsigargin treatment of β cells in vitro induces a picture of ER stress and apoptosis similar to that seen in db/db mice; in this setting, DHS inhibition led to a block in CHOP (CAAT/enhancer binding protein homologous protein) production despite >30-fold activation of Chop gene transcription. Blockage of CHOP translation resulted in reduction of downstream caspase-3 cleavage and near-complete protection of cells from apoptotic death. DHS inhibition appeared to prevent the cytoplasmic co-localization of eIF5A with the ER, possibly precluding the participation of eIF5A in translational elongation at ER-based ribosomes. We conclude that hypusination by DHS is required for the ongoing production of proteins, particularly CHOP, in response to ER stress in the β cell.
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Affiliation(s)
- Reiesha D. Robbins
- From the Department of Pharmacology, University of Virginia, Charlottesville, Virginia 22904
| | - Sarah A. Tersey
- the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Takeshi Ogihara
- the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Dhananjay Gupta
- the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Thomas B. Farb
- the Lilly Research Labs, Eli Lilly and Company, Indianapolis, Indiana 46285, and
| | - James Ficorilli
- the Lilly Research Labs, Eli Lilly and Company, Indianapolis, Indiana 46285, and
| | - Krister Bokvist
- the Lilly Research Labs, Eli Lilly and Company, Indianapolis, Indiana 46285, and
| | - Bernhard Maier
- the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Raghavendra G. Mirmira
- the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202
- the Departments of Medicine and of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana 46202
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Sun Z, Cheng Z, Taylor CA, McConkey BJ, Thompson JE. Apoptosis induction by eIF5A1 involves activation of the intrinsic mitochondrial pathway. J Cell Physiol 2010; 223:798-809. [PMID: 20232312 DOI: 10.1002/jcp.22100] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The regulatory role of eukaryotic translation initiation factor 5A1 (eIF5A1) in apoptosis was examined using HT-29 and HeLa S3 cells. eIF5A is the only known protein to contain the unusual amino acid, hypusine, and eIF5A1 is one of two human eIF5A family members. Two observations indicated that eIF5A1 is involved in apoptosis. First, siRNA-mediated suppression of eIF5A1 resulted in inhibition of apoptosis induced by various apoptotic stimuli, and second, adenovirus-mediated over-expression of eIF5A1 strongly induced apoptotic cell death. A mutant of eIF5A1 incapable of being hypusinated also induced apoptosis when over-expressed indicating that unhypusinated eIF5A1 is the pro-apoptotic form of the protein. Over-expression of eIF5A1 or of the mutant resulted in loss of mitochondrial transmembrane potential, translocation of Bax to the mitochondria, release of cytochrome c, caspase activation, up-regulation of p53, and up-regulation of Bim, a pro-apoptotic BH3-only Bcl-2 family protein. In addition, Bim(L) and Bim(S), the pro-apoptotic alternative spliced forms of Bim, were induced in response to over-expression of eIF5A1. Thus eIF5A1 appears to induce apoptosis by activating the mitochondrial apoptotic pathway. Proteomic analyses indicated that, of 1,899 proteins detected, 131 showed significant changes in expression (P or=1.5) within 72 h of eIF5A1 up-regulation. Among these are proteins involved in translation and protein folding, transcription factors, proteins mediating proteolysis, and a variety of proteins known to be directly involved in apoptosis. These observations collectively indicate that unhypusinated eIF5A1 plays a central role in the regulation of apoptosis.
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Affiliation(s)
- Zhong Sun
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
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34
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Maier B, Ogihara T, Trace AP, Tersey SA, Robbins RD, Chakrabarti SK, Nunemaker CS, Stull ND, Taylor CA, Thompson JE, Dondero RS, Lewis EC, Dinarello CA, Nadler JL, Mirmira RG. The unique hypusine modification of eIF5A promotes islet beta cell inflammation and dysfunction in mice. J Clin Invest 2010; 120:2156-70. [PMID: 20501948 PMCID: PMC2877928 DOI: 10.1172/jci38924] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 03/10/2010] [Indexed: 12/15/2022] Open
Abstract
In both type 1 and type 2 diabetes, pancreatic islet dysfunction results in part from cytokine-mediated inflammation. The ubiquitous eukaryotic translation initiation factor 5A (eIF5A), which is the only protein to contain the amino acid hypusine, contributes to the production of proinflammatory cytokines. We therefore investigated whether eIF5A participates in the inflammatory cascade leading to islet dysfunction during the development of diabetes. As described herein, we found that eIF5A regulates iNOS levels and that eIF5A depletion as well as the inhibition of hypusination protects against glucose intolerance in inflammatory mouse models of diabetes. We observed that following knockdown of eIF5A expression, mice were resistant to beta cell loss and the development of hyperglycemia in the low-dose streptozotocin model of diabetes. The depletion of eIF5A led to impaired translation of iNOS-encoding mRNA within the islet. A role for the hypusine residue of eIF5A in islet inflammatory responses was suggested by the observation that inhibition of hypusine synthesis reduced translation of iNOS-encoding mRNA in rodent beta cells and human islets and protected mice against the development of glucose intolerance the low-dose streptozotocin model of diabetes. Further analysis revealed that hypusine is required in part for nuclear export of iNOS-encoding mRNA, a process that involved the export protein exportin1. These observations identify the hypusine modification of eIF5A as a potential therapeutic target for preserving islet function under inflammatory conditions.
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Affiliation(s)
- Bernhard Maier
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Takeshi Ogihara
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Anthony P. Trace
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Sarah A. Tersey
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Reiesha D. Robbins
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Swarup K. Chakrabarti
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Craig S. Nunemaker
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Natalie D. Stull
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Catherine A. Taylor
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - John E. Thompson
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Richard S. Dondero
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Eli C. Lewis
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Charles A. Dinarello
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Jerry L. Nadler
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Raghavendra G. Mirmira
- Department of Pediatrics and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Department of Biochemistry and Molecular Genetics and
Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.
Department of Medicine and Strelitz Diabetes Center, Eastern Virginia Medical School, Norfolk, Virginia, USA.
Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Senesco Technologies Inc., New Brunswick, New Jersey, USA.
Department of Medicine, University of Colorado, Aurora, Colorado, USA.
Department of Medicine and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Landau G, Bercovich Z, Park MH, Kahana C. The role of polyamines in supporting growth of mammalian cells is mediated through their requirement for translation initiation and elongation. J Biol Chem 2010; 285:12474-81. [PMID: 20181941 PMCID: PMC2857121 DOI: 10.1074/jbc.m110.106419] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 02/18/2010] [Indexed: 12/16/2022] Open
Abstract
Polyamines are essential cell constituents whose depletion results in growth cessation. Here we have investigated potential mechanisms of action of polyamines in supporting mammalian cell proliferation. We demonstrate that polyamines regulate translation both at the initiation and at the elongation steps. L-alpha-difluoromethylornithine treatment resulting in polyamine depletion reduces protein synthesis via inhibition of translation initiation. N1-guanyl-diaminoheptane (GC7), a spermidine analogue that inhibits eukaryotic initiation factor 5A (eIF5A) hypusination, also caused inhibition of translation initiation. In contrast, depletion of eIF5A by short hairpin RNA inhibits translation elongation as was recently demonstrated in yeast and Drosophila. These results suggest that in addition to competing with spermidine in the hypusination reaction, GC7 also competes with spermidine at yet undefined sites required for translation initiation. Finally, we show that either polyamine depletion or GC7 treatment induced eIF2alpha phosphorylation and reduced phosphorylation of 4E-BP, thus setting the molecular basis for the observed inhibition of translation initiation.
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Affiliation(s)
- Guy Landau
- From the
Department of Molecular Genetics, the Weizmann Institute of Science, Rehovot 76199, Israel and
| | - Zippi Bercovich
- From the
Department of Molecular Genetics, the Weizmann Institute of Science, Rehovot 76199, Israel and
| | - Myung Hee Park
- the
Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892-4340
| | - Chaim Kahana
- From the
Department of Molecular Genetics, the Weizmann Institute of Science, Rehovot 76199, Israel and
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36
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Li CH, Ohn T, Ivanov P, Tisdale S, Anderson P. eIF5A promotes translation elongation, polysome disassembly and stress granule assembly. PLoS One 2010; 5:e9942. [PMID: 20376341 PMCID: PMC2848580 DOI: 10.1371/journal.pone.0009942] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Accepted: 03/09/2010] [Indexed: 12/13/2022] Open
Abstract
Stress granules (SGs) are cytoplasmic foci at which untranslated mRNAs accumulate in cells exposed to environmental stress. We have identified ornithine decarboxylase (ODC), an enzyme required for polyamine synthesis, and eIF5A, a polyamine (hypusine)-modified translation factor, as proteins required for arsenite-induced SG assembly. Knockdown of deoxyhypusine synthase (DHS) or treatment with a deoxyhypusine synthase inhibitor (GC7) prevents hypusine modification of eIF5A as well as arsenite-induced polysome disassembly and stress granule assembly. Time-course analysis reveals that this is due to a slowing of stress-induced ribosome run-off in cells lacking hypusine-eIF5A. Whereas eIF5A only marginally affects protein synthesis under normal conditions, it is required for the rapid onset of stress-induced translational repression. Our results reveal that hypusine-eIF5A-facilitated translation elongation promotes arsenite-induced polysome disassembly and stress granule assembly in cells subjected to adverse environmental conditions.
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Affiliation(s)
- Chi Ho Li
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
| | - Takbum Ohn
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
| | - Pavel Ivanov
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
| | - Sarah Tisdale
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
| | - Paul Anderson
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
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37
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Tang DJ, Dong SS, Ma NF, Xie D, Chen L, Fu L, Lau SH, Li Y, Li Y, Guan XY. Overexpression of eukaryotic initiation factor 5A2 enhances cell motility and promotes tumor metastasis in hepatocellular carcinoma. Hepatology 2010; 51:1255-63. [PMID: 20112425 DOI: 10.1002/hep.23451] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
UNLABELLED A high incidence of tumor recurrence and metastasis has been reported in hepatocellular carcinoma (HCC) patients; however, the underlying molecular mechanisms are largely unknown. In the present study a novel metastasis-related gene, eukaryotic initiation factor 5A2 (EIF5A2), was characterized for its role in HCC metastasis and underlying molecular mechanisms. Overexpression of EIF5A2 messenger RNA (mRNA) was detected in 50/81 (61.7%) of HCCs, which was significantly higher than those in nontumorous liver tissues. Compared with matched primary HCC, higher expression of EIF5A2 protein was observed in 25/47 (53.2%) of metastatic tumors. Functional studies found that ectopic expression of EIF5A2 could enhance cancer cell migration and invasion in vitro and tumor metastasis in vivo in an experimental mouse model. Moreover, inhibition of EIF5A by small interfering RNA (siRNA) or deoxyhypusine synthase (DHPS) inhibitor GC7, which inhibits EIF5A2 maturation, could effectively decrease cell motility. Further study found that EIF5A2 was able to induce epithelial-mesenchymal transition (EMT), a key event in tumor invasion and metastasis, characterized by down-regulation of epithelial markers (E-cadherin and beta-catenin) and up-regulation of mesenchymal markers (fibronectin, N-cadherin, alpha-SMA, and vimentin). In addition, EIF5A2 could also activate RhoA/Rac1 to stimulate the formation of stress fiber and lamellipodia. CONCLUSION EIF5A2 plays an important role in HCC invasion and metastasis by inducing EMT, as well as stimulating cytoskeleton rearrangement through activation of RhoA and Rac1.
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Affiliation(s)
- Dong-Jiang Tang
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong, China
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38
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Park MH, Nishimura K, Zanelli CF, Valentini SR. Functional significance of eIF5A and its hypusine modification in eukaryotes. Amino Acids 2010; 38:491-500. [PMID: 19997760 PMCID: PMC2829442 DOI: 10.1007/s00726-009-0408-7] [Citation(s) in RCA: 235] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 09/09/2009] [Indexed: 10/20/2022]
Abstract
The unusual basic amino acid, hypusine [N(epsilon)-(4-amino-2-hydroxybutyl)-lysine], is a modified lysine with the addition of the 4-aminobutyl moiety from the polyamine spermidine. This naturally occurring amino acid is a product of a unique posttranslational modification that occurs in only one cellular protein, eukaryotic translation initiation factor 5A (eIF5A, eIF-5A). Hypusine is synthesized exclusively in this protein by two sequential enzymatic steps involving deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH). The deoxyhypusine/hypusine synthetic pathway has evolved in archaea and eukaryotes, and eIF5A, DHS and DOHH are highly conserved suggesting a vital cellular function of eIF5A. Gene disruption and mutation studies in yeast and higher eukaryotes have provided valuable information on the essential nature of eIF5A and the deoxyhypusine/hypusine modification in cell growth and in protein synthesis. In view of the extraordinary specificity and functional significance of hypusine-containing eIF5A in mammalian cell proliferation, eIF5A and the hypusine biosynthetic enzymes are novel potential targets for intervention in aberrant cell proliferation.
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Affiliation(s)
- M H Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bldg 30, Room 211, Bethesda, MD 20892-4340, USA.
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39
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Abstract
Polyamines are ubiquitous small basic molecules that play multiple essential roles in mammalian physiology. Their cellular content is highly regulated and there is convincing evidence that altered metabolism is involvement in many disease states. Drugs altering polyamine levels may therefore have a variety of important targets. This review will summarize the current state of understanding of polyamine metabolism and function, the regulation of polyamine content, and heritable pathological conditions that may be derived from altered polyamine metabolism.
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Affiliation(s)
- Anthony E Pegg
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
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40
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Hoque M, Hanauske-Abel HM, Palumbo P, Saxena D, D'Alliessi Gandolfi D, Park MH, Pe'ery T, Mathews MB. Inhibition of HIV-1 gene expression by Ciclopirox and Deferiprone, drugs that prevent hypusination of eukaryotic initiation factor 5A. Retrovirology 2009; 6:90. [PMID: 19825182 PMCID: PMC2770518 DOI: 10.1186/1742-4690-6-90] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Accepted: 10/13/2009] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Eukaryotic translation initiation factor eIF5A has been implicated in HIV-1 replication. This protein contains the apparently unique amino acid hypusine that is formed by the post-translational modification of a lysine residue catalyzed by deoxyhypusine synthase and deoxyhypusine hydroxylase (DOHH). DOHH activity is inhibited by two clinically used drugs, the topical fungicide ciclopirox and the systemic medicinal iron chelator deferiprone. Deferiprone has been reported to inhibit HIV-1 replication in tissue culture. RESULTS Ciclopirox and deferiprone blocked HIV-1 replication in PBMCs. To examine the underlying mechanisms, we investigated the action of the drugs on eIF5A modification and HIV-1 gene expression in model systems. At early times after drug exposure, both drugs inhibited substrate binding to DOHH and prevented the formation of mature eIF5A. Viral gene expression from HIV-1 molecular clones was suppressed at the RNA level independently of all viral genes. The inhibition was specific for the viral promoter and occurred at the level of HIV-1 transcription initiation. Partial knockdown of eIF5A-1 by siRNA led to inhibition of HIV-1 gene expression that was non-additive with drug action. These data support the importance of eIF5A and hypusine formation in HIV-1 gene expression. CONCLUSION At clinically relevant concentrations, two widely used drugs blocked HIV-1 replication ex vivo. They specifically inhibited expression from the HIV-1 promoter at the level of transcription initiation. Both drugs interfered with the hydroxylation step in the hypusine modification of eIF5A. These results have profound implications for the potential therapeutic use of these drugs as antiretrovirals and for the development of optimized analogs.
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Affiliation(s)
- Mainul Hoque
- Department of Biochemistry & Molecular Biology, UMDNJ-New Jersey Medical School, NJ 07103, USA
| | - Hartmut M Hanauske-Abel
- Department of Obstetrics, Gynecology & Women's Health, UMDNJ-New Jersey Medical School, NJ 07103, USA
- Department of Pediatrics, UMDNJ-New Jersey Medical School, NJ 07103, USA
| | - Paul Palumbo
- Department of Pediatrics, UMDNJ-New Jersey Medical School, NJ 07103, USA
- Current Address: Section of Infectious Diseases and International Health, Dartmouth Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA
| | - Deepti Saxena
- Department of Pediatrics, UMDNJ-New Jersey Medical School, NJ 07103, USA
- Current Address: Section of Infectious Diseases and International Health, Dartmouth Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA
| | | | - Myung Hee Park
- National Institute for Dental and Craniofacial Research, NIH, MD 20892, USA
| | - Tsafi Pe'ery
- Department of Biochemistry & Molecular Biology, UMDNJ-New Jersey Medical School, NJ 07103, USA
- Department of Medicine, UMDNJ-New Jersey Medical School, NJ 07103, USA
| | - Michael B Mathews
- Department of Biochemistry & Molecular Biology, UMDNJ-New Jersey Medical School, NJ 07103, USA
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41
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Abdelhady MIS, Beuerle T, Ober D. Homospermidine in transgenic tobacco results in considerably reduced spermidine levels but is not converted to pyrrolizidine alkaloid precursors. PLANT MOLECULAR BIOLOGY 2009; 71:145-55. [PMID: 19543980 DOI: 10.1007/s11103-009-9514-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 06/04/2009] [Indexed: 05/27/2023]
Abstract
Homospermidine synthase is the first specific enzyme in the biosynthesis of pyrrolizidine alkaloids. Whereas the substrates putrescine and spermidine are part of the highly dynamic polyamine pool of plants, the product homospermidine is incorporated exclusively into the necine base moiety of pyrrolizidine alkaloids. Recently, the gene encoding homospermidine synthase has been shown to have been recruited several times independently during angiosperm evolution by the duplication of the gene encoding deoxyhypusine synthase. To test whether high levels of homospermidine suffice for conversion, at least in traces, to precursors of pyrrolizidine alkaloids, transgenic tobacco plants were generated expressing homospermidine synthase. Analyses of the polyamine content revealed that, in the transgenic plants, about 80% of spermidine was replaced by homospermidine without any conspicuous modifications of the phenotype. Tracer-feeding experiments and gas chromatographic analyses suggested that these high levels of homospermidine were not sufficient to explain the formation of alkaloid precursors. These results are discussed with respect to current models of pathway evolution.
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Affiliation(s)
- Mohamed I S Abdelhady
- Botanisches Institut und Botanischer Garten, Universität Kiel, Olshausenstrasse 40, Kiel, Germany.
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42
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Patel PH, Costa-Mattioli M, Schulze KL, Bellen HJ. The Drosophila deoxyhypusine hydroxylase homologue nero and its target eIF5A are required for cell growth and the regulation of autophagy. J Cell Biol 2009; 185:1181-94. [PMID: 19546244 PMCID: PMC2712966 DOI: 10.1083/jcb.200904161] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 05/28/2009] [Indexed: 11/24/2022] Open
Abstract
Hypusination is a unique posttranslational modification by which lysine is transformed into the atypical amino acid hypusine. eIF5A (eukaryotic initiation factor 5A) is the only known protein to contain hypusine. In this study, we describe the identification and characterization of nero, the Drosophila melanogaster deoxyhypusine hydroxylase (DOHH) homologue. nero mutations affect cell and organ size, bromodeoxyuridine incorporation, and autophagy. Knockdown of the hypusination target eIF5A via RNA interference causes phenotypes similar to nero mutations. However, loss of nero appears to cause milder phenotypes than loss of eIF5A. This is partially explained through a potential compensatory mechanism by which nero mutant cells up-regulate eIF5A levels. The failure of eIF5A up-regulation to rescue nero mutant phenotypes suggests that hypusination is required for eIF5A function. Furthermore, expression of enzymatically impaired forms of DOHH fails to rescue nero clones, indicating that hypusination activity is important for nero function. Our data also indicate that nero and eIF5A are required for cell growth and affect autophagy and protein synthesis.
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Affiliation(s)
- Prajal H. Patel
- Program in Developmental Biology, Department of Molecular and Human Genetics, Department of Neuroscience, and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030
| | - Mauro Costa-Mattioli
- Program in Developmental Biology, Department of Molecular and Human Genetics, Department of Neuroscience, and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030
| | - Karen L. Schulze
- Program in Developmental Biology, Department of Molecular and Human Genetics, Department of Neuroscience, and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030
| | - Hugo J. Bellen
- Program in Developmental Biology, Department of Molecular and Human Genetics, Department of Neuroscience, and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030
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43
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Gosslau A, Jao DLE, Butler R, Liu AYC, Chen KY. Thermal killing of human colon cancer cells is associated with the loss of eukaryotic initiation factor 5A. J Cell Physiol 2009; 219:485-93. [PMID: 19160416 DOI: 10.1002/jcp.21696] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Heat-induced cell death appears to be a cell-specific event. Chronic heat stress was lethal to human colon cancer cells (Caco-2, HT29, and HCT116), but not to normal diploid fibroblasts and other cancer cells (BJ-T, WI38, HeLa, ovarian 2008, WI38VA). Acute heat stress (45-51 degrees C, 30 min) caused cell death of colon cancer cells during recovery at physiological temperature. Thermal killing of Caco-2 cells was not mediated via oxidative stress since Caco-2 cells were much more resistant than HeLa and other cancer cells to H(2)O(2)-induced cell death. Acute heat stress caused a striking loss of eukaryotic initiation factor 5A (eIF5A) in colon cancer cells, but not in HeLa and other normal or transformed human fibroblasts. The heat-induced loss of eIF5A is likely to be due to changes in the protein stability. The half-life of eIF5A was changed from >20 h to less than 30 min during the acute heat stress. Sequence analysis of the eIF5A gene from Caco-2 and HeLa cells did not reveal any difference, suggesting that the change in stability in Caco-2 cells was not due to any eIF5A mutation. Pretreatment of cells with protease inhibitors such as phenylmethyl sulfonyl fluoride (PMSF) partially blocked the heat-induced loss of eIF5A and prevented heat-induced cell death. In light of the essential role of eIF5A in cell survival and proliferation, our results suggest that the stability of eIF5A may have an important role in determining the fate of the particular cell type after severe heat stress.
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Affiliation(s)
- Alexander Gosslau
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, USA
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44
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Koncarevic S, Urig S, Steiner K, Rahlfs S, Herold-Mende C, Sueltmann H, Becker K. Differential genomic and proteomic profiling of glioblastoma cells exposed to terpyridineplatinum(II) complexes. Free Radic Biol Med 2009; 46:1096-108. [PMID: 19439228 DOI: 10.1016/j.freeradbiomed.2009.01.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 12/09/2008] [Accepted: 01/11/2009] [Indexed: 11/18/2022]
Abstract
Terpyridineplatinum(II) complexes (TPCs) efficiently inhibit the proliferation of glioblastoma cells in vitro and have been tested successfully in a rodent glioblastoma model. Apart from intercalation with DNA, the major mechanism of action of TPCs is a very potent and specific interaction with the human selenoprotein thioredoxin reductase (TrxR). TrxR plays a crucial role in cellular redox homeostasis and protection against oxidative damage. In many malignant cells the thioredoxin system is upregulated, promoting tumor growth and progression. Thus, the thioredoxin system has been proposed to be an attractive target for cancer therapy. This study gives the first comprehensive overview of the effects of TPCs on the transcriptome and proteome of glioblastoma cells. We reveal that under TPC treatment, mechanisms countersteering TrxR inhibition are activated in parallel to DNA-damage-responsive pathways. TPC pressure results in long-term compensatory upregulation of TrxR expression. In parallel, p53 is activated, leading to a range of regulations typical for cell-cycle-arrested cells such as upregulation of CDKN1A, induction of GADD45, inhibition of eIF5A maturation, and reduced phosphorylation of stathmin. We also show that TPCs induce endoplasmic reticulum stress, as they activate the unfolded protein response. This profiling study provides a thorough insight into the spectrum of cellular events resulting from specific TrxR inhibition and characterizes the TPC mode of action.
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Affiliation(s)
- Sasa Koncarevic
- Interdisciplinary Research Center, Justus-Liebig University, Giessen, Germany
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45
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Chattopadhyay MK, Park MH, Tabor H. Hypusine modification for growth is the major function of spermidine in Saccharomyces cerevisiae polyamine auxotrophs grown in limiting spermidine. Proc Natl Acad Sci U S A 2008; 105:6554-9. [PMID: 18451031 PMCID: PMC2373341 DOI: 10.1073/pnas.0710970105] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Indexed: 11/18/2022] Open
Abstract
Spermidine and its derivative, hypusinated eIF5A, are essential for the growth of Saccharomyces cerevisiae. Very low concentrations of spermidine (10(-8) M) are sufficient for the growth of S. cerevisiae polyamine auxotrophs (spe1Delta, spe2Delta, and spe3Delta). Under these conditions, even though the growth rate is near normal, the internal concentration of spermidine is <0.2% of the spermidine concentration present in wild-type cells. When spe2Delta cells are grown with low concentrations of spermidine, there is a large decrease in the amount of hypusinated eukaryotic initiation factor 5A (eIF5A) (1/20 of normal), even though there is no change in the amount of total (modified plus unmodified) eIF5A. It is striking that, as intracellular spermidine becomes limiting, an increasing portion of it (up to 54%) is used for the hypusine modification of eIF5A. These data indicate that hypusine modification of eIF5A is a most important function for spermidine in supporting the growth of S. cerevisiae polyamine auxotrophs.
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Affiliation(s)
- Manas K. Chattopadhyay
- *Laboratory of Biochemistry and Genetics, National Institute of Diabetes, Digestive, and Kidney Diseases
| | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892
| | - Herbert Tabor
- *Laboratory of Biochemistry and Genetics, National Institute of Diabetes, Digestive, and Kidney Diseases
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46
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Dias CAO, Cano VSP, Rangel SM, Apponi LH, Frigieri MC, Muniz JRC, Garcia W, Park MH, Garratt RC, Zanelli CF, Valentini SR. Structural modeling and mutational analysis of yeast eukaryotic translation initiation factor 5A reveal new critical residues and reinforce its involvement in protein synthesis. FEBS J 2008; 275:1874-88. [PMID: 18341589 PMCID: PMC5278519 DOI: 10.1111/j.1742-4658.2008.06345.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Eukaryotic translation initiation factor 5A (eIF5A) is a protein that is highly conserved and essential for cell viability. This factor is the only protein known to contain the unique and essential amino acid residue hypusine. This work focused on the structural and functional characterization of Saccharomyces cerevisiae eIF5A. The tertiary structure of yeast eIF5A was modeled based on the structure of its Leishmania mexicana homologue and this model was used to predict the structural localization of new site-directed and randomly generated mutations. Most of the 40 new mutants exhibited phenotypes that resulted from eIF-5A protein-folding defects. Our data provided evidence that the C-terminal alpha-helix present in yeast eIF5A is an essential structural element, whereas the eIF5A N-terminal 10 amino acid extension not present in archaeal eIF5A homologs, is not. Moreover, the mutants containing substitutions at or in the vicinity of the hypusine modification site displayed nonviable or temperature-sensitive phenotypes and were defective in hypusine modification. Interestingly, two of the temperature-sensitive strains produced stable mutant eIF5A proteins--eIF5A(K56A) and eIF5A(Q22H,L93F)--and showed defects in protein synthesis at the restrictive temperature. Our data revealed important structural features of eIF5A that are required for its vital role in cell viability and underscored an essential function of eIF5A in the translation step of gene expression.
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Affiliation(s)
- Camila A O Dias
- Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University-UNESP, Rodovia Araraquara-Jaú km. 1, Araraquara, São Paulo, Brazil
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47
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Cano VSP, Jeon GA, Johansson HE, Henderson CA, Park JH, Valentini SR, Hershey JWB, Park MH. Mutational analyses of human eIF5A-1--identification of amino acid residues critical for eIF5A activity and hypusine modification. FEBS J 2008; 275:44-58. [PMID: 18067580 PMCID: PMC2536608 DOI: 10.1111/j.1742-4658.2007.06172.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The eukaryotic translation initiation factor 5A (eIF5A) is the only protein that contains hypusine [Nepsilon-(4-amino-2-hydroxybutyl)lysine], which is required for its activity. Hypusine is formed by post-translational modification of one specific lysine (Lys50 for human eIF5A) by deoxyhypusine synthase and deoxyhypusine hydroxylase. To investigate the features of eIF5A required for its activity, we generated 49 mutations in human eIF5A-1, with a single amino acid substitution at the highly conserved residues or with N-terminal or C-terminal truncations, and tested mutant proteins in complementing the growth of a Saccharomyces cerevisiae eIF5A null strain. Growth-supporting activity was abolished in only a few mutant eIF5As (K47D, G49A, K50A, K50D, K50I, K50R, G52A and K55A), with substitutions at or near the hypusine modification site or with truncation of 21 amino acids from either the N-terminus or C-terminus. The inactivity of the Lys50 substitution proteins is obviously due to lack of deoxyhypusine modification. In contrast, K47D and G49A were effective substrates for deoxyhypusine synthase, yet failed to support growth, suggesting critical roles of Lys47 and Gly49 in eIF5A activity, possibly in its interaction with effector(s). By use of a UBHY-R strain harboring genetically engineered unstable eIF5A, we present evidence for the primary function of eIF5A in protein synthesis. When selected eIF5A mutant proteins were tested for their activity in protein synthesis, a close correlation was observed between their ability to enhance protein synthesis and growth, lending further support for a central role of eIF5A in translation.
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Affiliation(s)
- Veridiana S. P. Cano
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892 USA
| | - Geoung A Jeon
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892 USA
| | | | | | - Jong-Hwan Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892 USA
| | | | | | - Myung Hee Park
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892 USA
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48
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Zanelli CF, Valentini SR. Is there a role for eIF5A in translation? Amino Acids 2007; 33:351-8. [PMID: 17578650 DOI: 10.1007/s00726-007-0533-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Accepted: 02/01/2007] [Indexed: 12/14/2022]
Abstract
The putative translation factor eIF5A is essential for cell viability and is highly conserved from archaebacteria to mammals. This factor is the only cellular protein that undergoes an essential posttranslational modification dependent on the polyamine spermidine, called hypusination. This review focuses on the functional characterization of eIF5A. Although this protein was originally identified as a translation initiation factor, subsequent studies did not support a role for eIF5A in general translation initiation. eIF5A has also been implicated in nuclear export of HIV-1 Rev and mRNA decay, but these findings are controversial in the literature and may reflect secondary effects of eIF-5A function. Next, the involvement of eIF5A and hypusination in the control of the cell cycle and proliferation in various organisms is reviewed. Finally, recent evidence in favor of reconsidering the role of eIF5A as a translation factor is discussed. Future studies may reveal the specific mechanism by which eIF5A affects protein synthesis.
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Affiliation(s)
- C F Zanelli
- Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University - UNESP, Araraquara, Brazil
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49
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Wolff EC, Kang KR, Kim YS, Park MH. Posttranslational synthesis of hypusine: evolutionary progression and specificity of the hypusine modification. Amino Acids 2007; 33:341-50. [PMID: 17476569 PMCID: PMC2572820 DOI: 10.1007/s00726-007-0525-0] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2007] [Accepted: 02/23/2007] [Indexed: 10/23/2022]
Abstract
A naturally occurring unusual amino acid, hypusine [N (epsilon)-(4-amino-2-hydroxybutyl)-lysine] is a component of a single cellular protein, eukaryotic translation initiation factor 5A (eIF5A). It is a modified lysine with structural contribution from the polyamine spermidine. Hypusine is formed in a novel posttranslational modification that involves two enzymes, deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH). eIF5A and deoxyhypusine/hypusine modification are essential for growth of eukaryotic cells. The hypusine synthetic pathway has evolved in eukaryotes and eIF5A, DHS and DOHH are highly conserved, suggesting maintenance of a fundamental cellular function of eIF5A through evolution. The unique feature of the hypusine modification is the strict specificity of the enzymes toward its substrate protein, eIF5A. Moreover, DHS exhibits a narrow specificity toward spermidine. In view of the extraordinary specificity and the requirement for hypusine-containing eIF5A for mammalian cell proliferation, eIF5A and the hypusine biosynthetic enzymes present new potential targets for intervention in aberrant cell proliferation.
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Affiliation(s)
- E C Wolff
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4340, USA
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50
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Kang KR, Kim YS, Wolff EC, Park MH. Specificity of the deoxyhypusine hydroxylase-eukaryotic translation initiation factor (eIF5A) interaction: identification of amino acid residues of the enzyme required for binding of its substrate, deoxyhypusine-containing eIF5A. J Biol Chem 2007; 282:8300-8. [PMID: 17213197 PMCID: PMC1852541 DOI: 10.1074/jbc.m607495200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Deoxyhypusine hydroxylase (DOHH) is a novel metalloenzyme that catalyzes the final step of the post-translational synthesis of hypusine (Nepsilon-(4-amino-2-hydroxybutyl)lysine) in the eukaryotic translation initiation factor 5A (eIF5A). Hypusine synthesis is unique in that it occurs in only one protein, denoting the strict specificity of the modification enzymes toward the substrate protein. The specificity of the interaction between eIF5A and DOHH was investigated using human eIF5A (eIF5A-1 isoform) and human recombinant DOHH. DOHH displayed a strong preference for binding the deoxyhypusine-containing form of eIF5A, over the eIF5A precursor or the hypusine-containing eIF5A, indicating a role for the deoxyhypusine residue in binding. In addition to the deoxyhypusine residue, a large portion of the eIF5A polypeptide (>20-90 amino acids) is required for effective modification by DOHH. We have identified the amino acid residues of DOHH that are critical for substrate binding by alanine substitution of 36 conserved amino acid residues. Of these, alanine substitution at Glu57, Glu90, Glu208, Glu241, Gly63, or Gly214 caused a severe impairment in eIF5A(Dhp) binding, with a complete loss of binding and activity in the E57A and E208A mutant enzymes. Only aspartate substitution mutants, E57D or E208D, retained partial activity and substrate binding, whereas alanine, glutamine, or asparagine mutants did not. These findings support a proposed model of DOHH-eIF5A binding in which the amino group(s) of the deoxyhypusine side chain of the substrate is primarily anchored by gamma-carboxyl groups of Glu57 and Glu208 at the DOHH active site.
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Affiliation(s)
| | | | - Edith C. Wolff
- From the Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892
| | - Myung Hee Park
- From the Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892
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