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Varlamova EA, Isagulieva AK, Morozova NG, Shmendel EV, Maslov MA, Shtil AA. Non-Phosphorus Lipids As New Antitumor Drug Prototypes. Russ J Bioorg Chem 2021. [DOI: 10.1134/s1068162021050356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
Among low molecular weight substances, polyamines (spermidine, spermine and their precursor putrescine) are present in eukaryotic cells at the mM level together with ATP and glutathione. It is expected therefore that polyamines play important roles in cell proliferation and viability. Polyamines mainly exist as a polyamine-RNA complex and regulate protein synthesis. It was found that polyamines enhance translation from inefficient mRNAs. The detailed mechanisms of polyamine stimulation of specific kinds of protein syntheses and the physiological functions of these proteins are described in this review. Spermine is metabolized into acrolein (CH2 = CH-CHO) and hydrogen peroxide (H2O2) by spermine oxidase. Although it is thought that cell damage is mainly caused by reactive oxygen species (O2-, H2O2, and •OH), it was found that acrolein is much more toxic than H2O2. Accordingly, the level of acrolein produced becomes a useful biomarker for several tissue-damage diseases like brain stroke. Thus, the mechanisms of cell toxicity caused by acrolein are described in this review.
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Affiliation(s)
- Kazuei Igarashi
- Amine Pharma Research Institute, Innovation Plaza at Chiba University, 1-8-15 Inohana, Chuo-ku, Chiba, Chiba, 260-0856, Japan.
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, Chiba, 260-8675, Japan.
| | - Keiko Kashiwagi
- Faculty of Pharmacy, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba, 288-0025, Japan
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Sakamoto A, Terui Y, Uemura T, Igarashi K, Kashiwagi K. Translational Regulation of Clock Genes BMAL1 and REV-ERBα by Polyamines. Int J Mol Sci 2021; 22:1307. [PMID: 33525630 PMCID: PMC7865260 DOI: 10.3390/ijms22031307] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 01/26/2021] [Indexed: 11/16/2022] Open
Abstract
Polyamines stimulate the synthesis of specific proteins at the level of translation, and the genes encoding these proteins are termed as the "polyamine modulon". The circadian clock generates daily rhythms in mammalian physiology and behavior. We investigated the role of polyamines in the circadian rhythm using control and polyamine-reduced NIH3T3 cells. The intracellular polyamines exhibited a rhythm with a period of about 24 h. In the polyamine-reduced NIH3T3 cells, the circadian period of circadian clock genes was lengthened and the synthesis of BMAL1 and REV-ERBα was significantly reduced at the translation level. Thus, the mechanism of polyamine stimulation of these protein syntheses was analyzed using NIH3T3 cells transiently transfected with genes encoding enhanced green fluorescent protein (EGFP) fusion mRNA with normal or mutated 5'-untranslated region (5'-UTR) of Bmal1 or Rev-erbα mRNA. It was found that polyamines stimulated BMAL1 and REV-ERBα synthesis through the enhancement of ribosomal shunting during the ribosome shunting within the 5'-UTR of mRNAs. Accordingly, the genes encoding Bmal1 and Rev-erbα were identified as the members of "polyamine modulon", and these two proteins are significantly involved in the circadian rhythm control.
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Affiliation(s)
- Akihiko Sakamoto
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba 288-0025, Japan; (A.S.); (Y.T.)
| | - Yusuke Terui
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba 288-0025, Japan; (A.S.); (Y.T.)
| | - Takeshi Uemura
- Amine Pharma Research Institute, Innovation Plaza at Chiba University, Chiba 260-0856, Japan; (T.U.); (K.I.)
- Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Kazuei Igarashi
- Amine Pharma Research Institute, Innovation Plaza at Chiba University, Chiba 260-0856, Japan; (T.U.); (K.I.)
- Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Keiko Kashiwagi
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba 288-0025, Japan; (A.S.); (Y.T.)
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Nakamura A, Takahashi D, Nakamura Y, Yamada T, Matsumoto M, Hase K. Polyamines polarized Th2/Th9 cell-fate decision by regulating GATA3 expression. Arch Biochem Biophys 2020; 693:108587. [PMID: 32946839 DOI: 10.1016/j.abb.2020.108587] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 01/26/2023]
Abstract
Polyamines produced by both prokaryotes and eukaryotes are bioactive substances with pleiotropic effects. Accumulating evidence has demonstrated that polyamines contribute to anti-inflammatory responses by suppressing the expression of proinflammatory cytokines in mononuclear cells and macrophages. However, the effects of polyamines on CD4+ T cell responses remain to be elucidated. Here, we investigated the effect of polyamines on cell fate decisions of naïve CD4+ T cells in vitro. We found that endogenously generated polyamines are essential for the development of T helper 2 (Th2) cells. Treatment with DL-2-difluoromethylornithine (DFMO), an inhibitor of polyamine biosynthesis, diminished GATA3 expression in CD4+ T cells under Th2-skewed conditions. Supplementation of exogenous polyamines rescued GATA3 downregulation caused by DFMO treatment in CD4+ T cells. Transcriptome analysis revealed that deprivation of endogenous polyamines resulted in upregulated Th9-related genes, such as Il9, Irf4, and Batf3, even under the Th2-skewing conditions. Depletion of intracellular polyamines reduced GATA3 expression but increased IL-9-producing CD4+ T cells under both Th2 and Th9-skewing conditions. Furthermore, oral administration of DFMO increased IL-9-producing CD4+ T cells in small intestine in mice. Thus, our data indicate that polyamines play a critical role in the regulation of the Th2/Th9 balance.
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Affiliation(s)
- Atsuo Nakamura
- Division of Biochemistry, Faculty of Pharmacy and Graduate School of Pharmaceutical Science, Keio University, Minato-ku, Tokyo, Japan; Dairy Science and Technology Institute, Kyodo Milk Industry Co Ltd., Hinode-machi, Tokyo, Japan
| | - Daisuke Takahashi
- Division of Biochemistry, Faculty of Pharmacy and Graduate School of Pharmaceutical Science, Keio University, Minato-ku, Tokyo, Japan.
| | - Yutaka Nakamura
- Division of Biochemistry, Faculty of Pharmacy and Graduate School of Pharmaceutical Science, Keio University, Minato-ku, Tokyo, Japan
| | - Takahiro Yamada
- Division of Biochemistry, Faculty of Pharmacy and Graduate School of Pharmaceutical Science, Keio University, Minato-ku, Tokyo, Japan
| | - Mitsuharu Matsumoto
- Dairy Science and Technology Institute, Kyodo Milk Industry Co Ltd., Hinode-machi, Tokyo, Japan.
| | - Koji Hase
- Division of Biochemistry, Faculty of Pharmacy and Graduate School of Pharmaceutical Science, Keio University, Minato-ku, Tokyo, Japan; International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo (IMSUT), Bunkyo-ku, Tokyo, Japan
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Sakamoto A, Terui Y, Uemura T, Igarashi K, Kashiwagi K. Polyamines regulate gene expression by stimulating translation of histone acetyltransferase mRNAs. J Biol Chem 2020; 295:8736-8745. [PMID: 32376690 DOI: 10.1074/jbc.ra120.013833] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/02/2020] [Indexed: 12/16/2022] Open
Abstract
Polyamines regulate gene expression in Escherichia coli by translationally stimulating mRNAs encoding global transcription factors. In this study, we focused on histone acetylation, one of the mechanisms of epigenetic regulation of gene expression, to attempt to clarify the role of polyamines in the regulation of gene expression in eukaryotes. We found that activities of histone acetyltransferases in both the nucleus and cytoplasm decreased significantly in polyamine-reduced mouse mammary carcinoma FM3A cells. Although protein levels of histones H3 and H4 did not change in control and polyamine-reduced cells, acetylation of histones H3 and H4 was greatly decreased in the polyamine-reduced cells. Next, we used control and polyamine-reduced cells to identify histone acetyltransferases whose synthesis is stimulated by polyamines. We found that polyamines stimulate the translation of histone acetyltransferases GCN5 and HAT1. Accordingly, GCN5- and HAT1-catalyzed acetylation of specific lysine residues on histones H3 and H4 was stimulated by polyamines. Consistent with these findings, transcription of genes required for cell proliferation was enhanced by polyamines. These results indicate that polyamines regulate gene expression by enhancing the expression of the histone acetyltransferases GCN5 and HAT1 at the level of translation. Mechanistically, polyamines enhanced the interaction of microRNA-7648-5p (miR-7648-5p) with the 5'-UTR of GCN5 mRNA, resulting in stimulation of translation due to the destabilization of the double-stranded RNA (dsRNA) between the 5'-UTR and the ORF of GCN5 mRNA. Because HAT1 mRNA has a short 5'-UTR, polyamines may enhance initiation complex formation directly on this mRNA.
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Affiliation(s)
- Akihiko Sakamoto
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan
| | - Yusuke Terui
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan
| | | | - Kazuei Igarashi
- Amine Pharma Research Institute, Chiba, Japan; Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Keiko Kashiwagi
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan.
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Nishimura K, Okamoto M, Shibue R, Mizuta T, Shibayama T, Yoshino T, Murakami T, Yamaguchi M, Tanaka S, Toida T, Igarashi K. KLF4 is required for suppression of histamine synthesis by polyamines during bone marrow-derived mast cell differentiation. PLoS One 2020; 15:e0229744. [PMID: 32101568 DOI: 10.1371/journal.pone.0229744] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/13/2020] [Indexed: 11/19/2022] Open
Abstract
Mast cells have secretory granules containing chemical mediators such as histamine and play important roles in the immune system. Polyamines are essential factors for cellular processes such as gene expression and translation. It has been reported that secretory granules contain both histamine and polyamines, which have similar chemical structures and are produced from the metabolism of cationic amino acids. We investigated the effect of polyamine depletion on mast cells using bone marrow-derived mast cells (BMMCs). Polyamine depletion was induced using α-difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase. DFMO treatment resulted in a significant reduction of cell number and abnormal secretory granules in BMMCs. Moreover, the cells showed a 2.3-fold increase in intracellular histamine and up-regulation of histidine decarboxylase (HDC) at the transcriptional level during BMMC differentiation. Levels of the transcription factor kruppel-like factor 4 (KLF4) greatly decreased upon DFMO treatment; however, Klf4 mRNA was expressed at levels similar to controls. We determined the translational regulation of KLF4 using reporter genes encoding Klf4-luc2 fusion mRNA, for transfecting NIH3T3 cells, and performed in vitro translation. We found that the efficiency of KLF4 synthesis in response to DFMO treatment was enhanced by the existence of a GC-rich 5'-untranslated region (5'-UTR) on Klf4 mRNA, regardless of the recognition of the initiation codon. Taken together, these results indicate that the enhancement of histamine synthesis by DFMO depends on the up-regulation of Hdc expression, achieved by removal of transcriptional suppression of KLF4, during differentiation.
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Igarashi K, Kashiwagi K. The functional role of polyamines in eukaryotic cells. Int J Biochem Cell Biol 2019; 107:104-15. [PMID: 30578954 DOI: 10.1016/j.biocel.2018.12.012] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 12/15/2018] [Accepted: 12/19/2018] [Indexed: 11/22/2022]
Abstract
Polyamines, consisting of putrescine, spermidine and spermine are essential for normal cell growth and viability in eukaryotic cells. Since polyamines are cations, they interact with DNA, ATP, phospholipids, specific kinds of proteins, and especially with RNA. Consequently, the functions of these acidic compounds and some proteins are modified by polyamines. In this review, the functional modifications of these molecules by polyamines are presented. Structural change of specific mRNAs by polyamines causes the stimulation of the synthesis of several different proteins, which are important for cell growth and viability. eIF5 A, the only known protein containing a spermidine derivative, i.e. hypusine, also functions at the level of translation. Experimental results thus far obtained strongly suggest that the most important function of polyamines is at the level of translation.
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Terui Y, Yoshida T, Sakamoto A, Saito D, Oshima T, Kawazoe M, Yokoyama S, Igarashi K, Kashiwagi K. Polyamines protect nucleic acids against depurination. Int J Biochem Cell Biol 2018; 99:147-153. [PMID: 29649565 DOI: 10.1016/j.biocel.2018.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/21/2018] [Accepted: 04/06/2018] [Indexed: 11/20/2022]
Abstract
Depurination is accelerated by heat and reactive oxygen species under physiological conditions. We previously reported that polyamines are involved in mitigation of heat shock and oxidative stresses through stimulation of the synthesis of heat shock and antioxidant proteins. This time, we investigated whether polyamines are directly involved in protecting nucleic acids from thermal depurination induced by high temperature. The suppressing efficiencies of depurination of DNA by spermine, caldopentamine and caldohexamine in the presence of 1 mM Mg2+, were approximately 50%, 60% and 80%, respectively. Mg2+ also protected nucleic acids against depurination but to a lesser degree than polyamines. Longer unusual polyamines were more effective at protecting DNA against depurination compared to standard polyamines. The tRNA depurination suppressing efficiencies of spermine, caldopentamine and caldohexamine in the presence of 1 mM Mg2+, were approximately 60%, 70% and 80%, respectively. Standard polyamines protected tRNA and ribosomes more effectively than DNA against thermal depurination. Branched polyamines such as mitsubishine and tetrakis(3-aminopropyl)ammonium also protected RNA more effectively than DNA against depurination. These results suggest that the suppressing effect of depurination of nucleic acids (DNA and RNA) depends on the types of polyamines: i.e. to maintain functional conformation of nucleic acids at high temperature, longer and branched polyamines play important roles in protecting nucleic acids from depurination compared to standard polyamines and Mg2+.
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Affiliation(s)
- Yusuke Terui
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan.
| | - Taketo Yoshida
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan
| | - Akihiko Sakamoto
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan
| | | | - Tairo Oshima
- Institute of Environmental Biology, Kyowa-Kako, Machida, Tokyo, Japan
| | | | | | - Kazuei Igarashi
- Amine Pharma Research Institute, Innovation Plaza at Chiba University, Chiba, Japan; Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Keiko Kashiwagi
- Faculty of Pharmacy, Chiba Institute of Science, Choshi, Chiba, Japan.
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Abstract
Polyamines exist mainly as RNA-polyamine complexes in cells. Thus, we looked for proteins whose synthesis is enhanced by polyamines at the level of translation in mammalian cells. Here, we describe how synthesis of Cct2 (T-complex protein 1, β-subunit, a chaperonin assisting in the folding actin, tubulin, and several other proteins) and eEF1A (one of the elongation factors of protein synthesis) is stimulated by polyamines at the level of translation. Polyamines stimulated Cct2 synthesis through the stimulation of ribosome shunting during 5'-processive scanning of 40S ribosomal subunits from the m7G-cap to the initiation codon AUG, and eEF1A synthesis through the structural change of the unusual position of a complementary sequence to 18S rRNA in eEF1A mRNA.
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Affiliation(s)
- Keiko Kashiwagi
- Faculty of Pharmacy, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba, 288-0025, Japan.
| | - Yusuke Terui
- Faculty of Pharmacy, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba, 288-0025, Japan
| | - Kazuei Igarashi
- Amine Pharma Research Institute, Innovation Plaza at Chiba University, 1-8-15 Inohana, Chuo-ku, Chiba, 260-0856, Japan
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan
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Oguro A, Yanagida A, Fujieda Y, Amano R, Otsu M, Sakamoto T, Kawai G, Matsufuji S. Two stems with different characteristics and an internal loop in an RNA aptamer contribute to spermine-binding. J Biochem 2017; 161:197-206. [PMID: 28173167 DOI: 10.1093/jb/mvw062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Accepted: 08/30/2016] [Indexed: 11/14/2022] Open
Abstract
Though polyamines (putrescine, spermidine, and spermine) bind to the specific position in RNA molecules, interaction mechanisms are poorly understood. SELEX procedure has been used to isolate high-affinity oligoribonucleotides (aptamers) from randomized RNA libraries. Selected aptamers are useful in exploring sequences and/or structures in RNAs for binding molecules. In this study, to analyze the interaction mechanism of polyamine to RNA, we selected RNA aptamers targeted for spermine. Two spermine-binding aptamers (#5 and #24) were obtained and both of them had two stem-loop structures. The 3′ stem-loop of #5 (SL_2) bound to spermine more effectively than the 5′ stem-loop of #5 did. A thermodynamic analysis by an isothermal titration calorimetry revealed that the dissociation constant of SL_2 for spermine was 27.2 μM and binding ratio was nearly 1:1. Binding assay with base-pair replaced variants showed that two stem regions and an internal loop in SL_2 were important for their spermine-binding activities. NMR analyses proposed that a terminal-side and a loop-side stem in SL_2 take a loose and a stable structure, respectively and a conformational change of SL_2 is induced by spermine. It is conclusive that two stems with different characteristics and an internal loop in SL_2 contribute to the specific spermine-binding.
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Affiliation(s)
- Akihiro Oguro
- Department of Molecular Biology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Asumi Yanagida
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Yuta Fujieda
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Ryo Amano
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Maina Otsu
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Taiichi Sakamoto
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Gota Kawai
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Senya Matsufuji
- Department of Molecular Biology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan
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Imamura M, Higashi K, Yamaguchi K, Asakura K, Furihata T, Terui Y, Satake T, Maegawa J, Yasumura K, Ibuki A, Akase T, Nishimura K, Kashiwagi K, Linhardt RJ, Igarashi K, Toida T. Polyamines release the let-7b-mediated suppression of initiation codon recognition during the protein synthesis of EXT2. Sci Rep 2016; 6:33549. [PMID: 27650265 DOI: 10.1038/srep33549] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 08/30/2016] [Indexed: 12/26/2022] Open
Abstract
Proteoglycans (PGs), a family of glycosaminoglycan (GAG)-protein glycoconjugates, contribute to animal physiology through interactions between their glycan chains and growth factors, chemokines and adhesion molecules. However, it remains unclear how GAG structures are changed during the aging process. Here, we found that polyamine levels are correlated with the expression level of heparan sulfate (HS) in human skin. In cultured cell lines, the EXT1 and EXT2 enzymes, initiating HS biosynthesis, were stimulated at the translational level by polyamines. Interestingly, the initiation codon recognition by 43S preinitiation complex during EXT2 translation is suppressed by let-7b, a member of the let-7 microRNA family, through binding at the N-terminal amino acid coding sequence in EXT2 mRNA. Let-7b-mediated suppression of initiation codon depends on the length of 5'-UTR of EXT2 mRNA and its suppression is inhibited in the presence of polyamines. These findings provide new insights into the HS biosynthesis related to miRNA and polyamines.
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Abstract
Polyamines are ubiquitous small basic molecules that play important roles in cell growth and viability. Since polyamines mainly exist as a polyamine-RNA complex, we looked for proteins whose synthesis is preferentially stimulated by polyamines at the level of translation, and thus far identified 17 proteins in Escherichia coli and 6 proteins in eukaryotes. The mechanisms of polyamine stimulation of synthesis of these proteins were investigated. In addition, the role of eIF5A, containing hypusine formed from spermidine, on protein synthesis is described. These results clearly indicate that polyamines and eIF5A contribute to cell growth and viability through modulation of protein synthesis.
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Affiliation(s)
- Kazuei Igarashi
- Department of Clinical Biochemistry, Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-Ku, Chiba, Japan; Amine Pharma Research Institute, Chuo-Ku, Chiba, Japan
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