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Gong T, Habara H, Sumioka K, Yoshimoto M, Hayashi Y, Kawazu S, Otsuki T, Matsumoto T, Minami T, Abe K, Aizawa K, Enmei Y, Fujita Y, Ikegami A, Makiyama H, Okazaki K, Okida K, Tsukamoto T, Arikawa Y, Fujioka S, Iwasa Y, Lee S, Nagatomo H, Shiraga H, Yamanoi K, Wei MS, Tanaka KA. Direct observation of imploded core heating via fast electrons with super-penetration scheme. Nat Commun 2019; 10:5614. [PMID: 31819056 PMCID: PMC6901506 DOI: 10.1038/s41467-019-13574-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 11/08/2019] [Indexed: 11/09/2022] Open
Abstract
Fast ignition (FI) is a promising approach for high-energy-gain inertial confinement fusion in the laboratory. To achieve ignition, the energy of a short-pulse laser is required to be delivered efficiently to the pre-compressed fuel core via a high-energy electron beam. Therefore, understanding the transport and energy deposition of this electron beam inside the pre-compressed core is the key for FI. Here we report on the direct observation of the electron beam transport and deposition in a compressed core through the stimulated Cu Kα emission in the super-penetration scheme. Simulations reproducing the experimental measurements indicate that, at the time of peak compression, about 1% of the short-pulse energy is coupled to a relatively low-density core with a radius of 70 μm. Analysis with the support of 2D particle-in-cell simulations uncovers the key factors improving this coupling efficiency. Our findings are of critical importance for optimizing FI experiments in a super-penetration scheme.
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Affiliation(s)
- T Gong
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan.,Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, People's Republic of China
| | - H Habara
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan.
| | - K Sumioka
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - M Yoshimoto
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Y Hayashi
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - S Kawazu
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - T Otsuki
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - T Matsumoto
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - T Minami
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - K Abe
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - K Aizawa
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Y Enmei
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Y Fujita
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - A Ikegami
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - H Makiyama
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - K Okazaki
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - K Okida
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - T Tsukamoto
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Y Arikawa
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - S Fujioka
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Y Iwasa
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - S Lee
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - H Nagatomo
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - H Shiraga
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - K Yamanoi
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - M S Wei
- Laboratory for Laser Energetics, University of Rochester, Rochester, NY, 14623-1299, USA
| | - K A Tanaka
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan. .,Extreme Light Infrastructure: Nuclear Physics, 30 Reatorului, Magurele-Bucharest, 077125, Romania.
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Nakamura S, Ikegami A, Mizuno M, Yagi F, Nomura K. The Expression Profile of Lectin Differs from That of Seed Storage Proteins inCastanea crenataTrees. Biosci Biotechnol Biochem 2014; 68:1698-705. [PMID: 15322353 DOI: 10.1271/bbb.68.1698] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Using Northern blot analysis, the expression of the Japanese chestnut (Castanea crenata Sieb. et Zucc.) agglutinin (CCA) gene was compared with that of its seed storage protein (SSP) gene. After cDNA cloning of SSP, the expression profile of SSP mRNA and CCA mRNA were compared. SSP mRNA was seed-specific, while CCA mRNA was expressed in the stems and flowers (both male and female) as well as in the seeds. Whereas extracts from all organs observed using Western blot analysis exhibited positive signals, in seeds, large expressions of SSP mRNA were restricted to the late maturation and harvest stages. Levels were maintained during the dormant period. No expression was observed during the germination stage. In contrast, CCA mRNA expression was maintained at a high level during development, was at a relatively low level during dormancy, and showed subsequent high expression during germination. These results suggest that one of the physiological roles of CCA is to act as a vegetative storage protein. But since protein expression did not coincide with that of mRNA, the expression of CCA may be regulated both at the transcription and the translation levels.
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Affiliation(s)
- Sachiko Nakamura
- Graduate School of Science and Technology, Kobe University, 1-1 Rokkodai-chou, Nada-ku, Kobe 657-8501, Japan
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Akagi T, Tsujimoto T, Ikegami A, Yonemori K. Effects of seasonal temperature changes on DkMyb4 expression involved in proanthocyanidin regulation in two genotypes of persimmon (Diospyros kaki Thunb.) fruit. Planta 2011; 233:883-894. [PMID: 21225280 DOI: 10.1007/s00425-010-1346-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Accepted: 12/22/2010] [Indexed: 05/30/2023]
Abstract
Persimmon fruits accumulate a large amount of proanthocyanidin (PA). Fruits of the mutant non-astringent (NA) type lose their ability to accumulate PA at an early stage of fruit development, whereas fruits of the normal astringent (A) type sustain PA accumulation until ripening. This allelotype is determined by the genotype of a single ASTRINGENCY (AST) locus. It is possible that the reduction in PA accumulation in NA-type fruits is due to phenological down-regulation of DkMyb4 (a PA regulator) and the resultant down-regulation of structural genes in the PA pathway. In this study, attempts were made to identify the regulatory mechanisms of phenological PA accumulation in A- and NA-type fruits, focusing particularly on the effects of ambient temperature. Continuous cool temperature conditions caused sustained expression of DkMyb4 in NA-type fruits, as well as in A-type fruits, resulting in increased expression of PA pathway genes and PA accumulation. However, the expression of some A/NA phenotypic marker genes was not significantly affected by the cool temperature conditions. In addition, PA composition in NA-type fruits exposed to cool temperatures differed from that in A-type fruits. These results indicate that a cool ambient temperature may have induced DkMyb4 expression and resultant PA accumulation, but did not directly affect the expression of the AST gene.
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Affiliation(s)
- Takashi Akagi
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Ikegami A, Eguchi S, Akagi T, Sato A, Yamada M, Kanzaki S, Kitajima A, Yonemori K. Development of Molecular Markers Linked to the Allele Associated with the Non-astringent Trait of the Chinese Persimmon (Diospyros kaki Thunb.). ACTA ACUST UNITED AC 2011. [DOI: 10.2503/jjshs1.80.150] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Akagi T, Ikegami A, Yonemori K. DkMyb2 wound-induced transcription factor of persimmon (Diospyros kaki Thunb.), contributes to proanthocyanidin regulation. Planta 2010; 232:1045-59. [PMID: 20690029 DOI: 10.1007/s00425-010-1241-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 07/23/2010] [Indexed: 05/22/2023]
Abstract
Proanthocyanidins (PAs) are secondary metabolites that contribute to the protection of a plant against biotic and abiotic stresses. Persimmon (Diospyros kaki) accumulates abundant PAs in each plant organ, and some potential Myb-like transcription factors (Myb-TFs) involved in the production of PAs have been isolated. In this study, we aimed to molecularly characterize one of them, DkMyb2, which was placed in a subclade including a PA regulator of Arabidopsis (Arabidopsis thaliana), TRANSPARENT TESTA2 (TT2), and was co-induced with PA pathway genes after wound stress. Ectopic DkMyb2 overexpression caused significant up-regulation of PA pathway genes in transgenic persimmon calluses and significant accumulation of PA, and increased mean degree of polymerization of PAs in transgenic kiwifruit calluses. Analysis of the DNA-binding ability of DkMyb2 by electrophoretic mobility shift assays showed that DkMyb2 directly binds to the AC-rich cis-motifs known as AC elements in the promoters of the two PA pathway genes in persimmon, DkANR, and DkLAR. Furthermore, a transient reporter assay using a dual-luciferase system demonstrated direct transcriptional activation of DkANR and DkLAR by DkMyb2. We also discuss subfunctionalization of two PA regulators in persimmon, DkMyb2 and DkMyb4, as well as PA regulators in other plant species from the viewpoint of their ability to bind to cis-motifs and their functions in transcriptional activation. Our results provide insight into the multiple regulatory mechanisms that control PA metabolism by Myb-TFs in persimmon.
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Affiliation(s)
- Takashi Akagi
- Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
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Abstract
The activity of bacteriorhodopsin was investigated with Halobacterium halobium cell envelopes, which lack cytoplasmic constituents. It was found that the physiological concentration of magnesium ion greatly enhanced the light-induced pH change; under optimal conditions, the pH change of the external medium was as large as 3.5 pH units, even though the volume fraction of the envelope vesicles was as low as 0.01. This pH change is about three times larger than the largest change reported thus far. This same effect was observed with transition metal ions, but not with other alkaline divalent cations. That is, divalent cations that formed hydroxides below pH 10 were effective in enhancing the light-induced pH change. This result suggests that some divalent cations acted as buffers against a large increase in the internal pH, and that the internal pH was an important factor in determining the activity of bacteriorhodopsin. It was also shown that a high level of the proton-pump activity was maintained in a wide range of external pHs, at least between 4.5 and 9.4.
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Otomo J, Tomioka A, Kinosita K, Miyata H, Takenaka Y, Kouyama T, Ikegami A. Chromophore of Bacteriorhodopsin is Closer to the Cytoplasmic Surface of Purple Membrane: Fluorescence Energy Transfer on Oriented Membrane Sheets. Biophys J 2010; 54:57-64. [PMID: 19431725 DOI: 10.1016/s0006-3495(88)82930-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Transmembrane location of the retinal chromophore, either native or reduced in situ to a fluorescent derivative, of the purple membrane of Halobacterium halobium was investigated with fluorescence energy transfer techniques. Single sheets of purple membrane, either native or reduced with borohydride, were adsorbed on polylysine-coated glass; the orientation, whether the exposed surfaces were cytoplasmic or extracellular, was controlled by adjusting the pH of the membrane suspension before the adsorption. On the exposed surface of the reduced membrane, a layer of cytochrome c, hemoglobin, or ferritin was deposited. The rate of excitation energy transfer from the fluorescent chromophore in the membrane to the colored protein was greater when the protein was on the cytoplasmic surface of the membrane than when it was on the extracellular surface. Analysis in which uniform distribution of the protein on the surface was assumed showed that the reduced chromophore is situated at a depth of <1.5 nm from the cytoplasmic surface. The location of the native retinal chromophore was examined by depositing a small amount of tris(2,2'-bipyridyl)ruthenium(II) complex on the native membrane adsorbed on the glass. Energy transfer from the luminescent complex to the retinal chromosphore was more efficient on the cytoplasmic surface than on the extracellular surface, suggesting that the native chromophore is also on the cytoplasmic side. From these and previous results we conclude that the chromophore, whether native or reduced, of bacteriorhodopsin is located at a depth of 1.0 +/- 0.3 nm from the cytoplasmic surface of purple membrane.
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Kometani T, Kinosita K, Furuno T, Kouyama T, Ikegami A. Transmembrane location of retinal in purple membrane: fluorescence energy transfer in maximally packed donor-acceptor systems. Biophys J 2010; 52:509-17. [PMID: 19431704 DOI: 10.1016/s0006-3495(87)83240-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Transmembrane location of the retinal chromophore in the purple membrane of Halobacterium halobium was investigated in three different systems in which excitation energy transfer between the chromophore and external dye molecules condensed on the membrane surfaces was observed. In system ii, the energy donor was the retinal chromophore converted in situ to a fluorescent derivative. The fluorescent membranes were embedded in solid cobalt-EDTA, which served as energy acceptors. System iii was similar to system ii, except that the acceptors were tris(2,2'-bipyridyl)ruthenium(II) complex in solid form. The positively charged ruthenium complex had a radius of 0.7 nm, whereas the cobalt complex in system ii was smaller (radius approximately 0.4 nm) and negatively charged. System iv was stacked sheets of native purple membrane with interspersed ruthenium complex; energy transfer from the luminescent ruthenuim complex to the native retinal chromophore was observed. The energy transfer rates in these three systems, and in two additional systems already described (Kouyama, T., K. Kinosita, Jr., and A. Ikegami, 1983, J. Mol. Biol., 165:91-107), were all consistent with a location of the retinal chromophore at a depth of 1.0 +/- 0.3 nm from a surface of the purple membrane. All the analyses in the present work involved an assumption that contacts between the external dye molecules and membrane surfaces were maximal; the depth values obtained cannot be underestimates. The chromophore therefore must be outside the middle one-third of the thickness, approximately 4.5 nm, of the purple membrane.
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Akagi T, Suzuki Y, Ikegami A, Kamitakahara H, Takano T, Nakatsubo F, Yonemori K. Condensed Tannin Composition Analysis in Persimmon (Diospyros kaki Thunb.) Fruit by Acid Catalysis in the Presence of Excess Phloroglucinol. ACTA ACUST UNITED AC 2010. [DOI: 10.2503/jjshs1.79.275] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Akagi T, Ikegami A, Tsujimoto T, Kobayashi S, Sato A, Kono A, Yonemori K. DkMyb4 is a Myb transcription factor involved in proanthocyanidin biosynthesis in persimmon fruit. Plant Physiol 2009; 151:2028-45. [PMID: 19783643 PMCID: PMC2785967 DOI: 10.1104/pp.109.146985] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 09/18/2009] [Indexed: 05/18/2023]
Abstract
Proanthocyanidins (PAs) are secondary metabolites that contribute to the protection of the plant and also to the taste of the fruit, mainly through astringency. Persimmon (Diospyros kaki) is unique in being able to accumulate abundant PAs in the fruit flesh. Fruits of the nonastringent (NA)-type mutants lose their ability to produce PA at an early stage of fruit development, while those of the normal astringent (A) type remain rich in PA until fully ripened. The expression of many PA pathway genes was coincidentally terminated in the NA type at an early stage of fruit development. The five genes encoding the Myb transcription factor were isolated from an A-type cultivar (Kuramitsu). One of them, DkMyb4, showed an expression pattern synchronous to that of the PA pathway genes in A- and NA-type fruit flesh. The ectopic expression of DkMyb4 in kiwifruit (Actinidia deliciosa) induced PA biosynthesis but not anthocyanin biosynthesis. The suppression of DkMyb4 in persimmon calluses caused a substantial down-regulation of the PA pathway genes and PA biosynthesis. Furthermore, analysis of the DNA-binding ability of DkMyb4 showed that it directly binds to the MYBCORE cis-motif in the promoters of the some PA pathway genes. All our results indicate that DkMyb4 acts as a regulator of PA biosynthesis in persimmon and, therefore, suggest that the reduction in the DkMyb4 expression causes the NA-type-specific down-regulation of PA biosynthesis and resultant NA trait.
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Tsuchiya R, Akutsu Y, Ikegami A, Scott M, Neo S, Ishikawa T, Hisasue M, Yamada T. Prothrombotic and Inflammatory Effects of Intravenous Administration of Human Immunoglobulin G in Dogs. J Vet Intern Med 2009; 23:1164-9. [DOI: 10.1111/j.1939-1676.2009.0402.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Akagi T, Ikegami A, Suzuki Y, Yoshida J, Yamada M, Sato A, Yonemori K. Expression balances of structural genes in shikimate and flavonoid biosynthesis cause a difference in proanthocyanidin accumulation in persimmon (Diospyros kaki Thunb.) fruit. Planta 2009; 230:899-915. [PMID: 19669159 DOI: 10.1007/s00425-009-0991-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Accepted: 07/14/2009] [Indexed: 05/22/2023]
Abstract
Persimmon fruits accumulate a large amount of proanthocyanidin (PA) during development. Fruits of pollination-constant and non-astringent (PCNA) type mutants lose their ability to produce PA at an early stage of fruit development, while fruits of the normal (non-PCNA) type remain rich in PA until fully ripened. To understand the molecular mechanism for this difference, we isolated the genes involved in PA accumulation that are differentially expressed between PCNA and non-PCNA, and confirmed their correlation with PA content and composition. The expression of structural genes of the shikimate and flavonoid biosynthetic pathways and genes encoding transferases homologous to those involved in the accumulation of phenolic compounds were downregulated coincidentally only in the PCNA type. Analysis of PA composition using the phloroglucinol method suggested that the amounts of epigallocatechin and its 3-O-gallate form were remarkably low in the PCNA type. In the PCNA type, the genes encoding flavonoid 3'5' hydroxylase (F3'5'H) and anthocyanidin reductase (ANR) for epigallocatechin biosynthesis showed remarkable downregulation, despite the continuous expression level of their competitive genes, flavonoid 3' hydroxylation (F3'H) and leucoanthocyanidin reductase (LAR). We also confirmed that the relative expression levels of F3'5'H to F3'H, and ANR to LAR, were considerably higher, and the PA composition corresponded to the seasonal expression balances in both types. These results suggest that expressions of F3'5'H and ANR are important for PA accumulation in persimmon fruit. Lastly, we tested enzymatic activity of recombinant DkANR in vitro, which is thought to be an important enzyme for PA accumulation in persimmon fruits.
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Affiliation(s)
- Takashi Akagi
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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Ikegami A, Akagi T, Potter D, Yamada M, Sato A, Yonemori K, Kitajima A, Inoue K. Molecular identification of 1-Cys peroxiredoxin and anthocyanidin/flavonol 3-O-galactosyltransferase from proanthocyanidin-rich young fruits of persimmon (Diospyros kaki Thunb.). Planta 2009; 230:841-55. [PMID: 19641937 PMCID: PMC2729980 DOI: 10.1007/s00425-009-0989-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 07/10/2009] [Indexed: 05/19/2023]
Abstract
Fruits of persimmon (Diospyros kaki Thunb.) accumulate large amounts of proanthocyanidins (PAs) in the early stages of development. Astringent (A)-type fruits remain rich in soluble PAs even after they reach full-mature stage, whereas non-astringent (NA)-type fruits lose these compounds before full maturation. As a first step to elucidate the mechanism of PA accumulation in this non-model species, we used suppression subtractive hybridization to identify transcripts accumulating differently in young fruits of A- and NA-type. Interestingly, only a few clones involved in PA biosynthesis were identified in A-NA libraries. Represented by multiple clones were those encoding a novel 1-Cys peroxiredoxin and a new member of family 1 glycosyltransferases. Quantitative RT-PCR analyses confirmed correlation of the amount of PAs and accumulation of transcripts encoding these proteins in young persimmon fruits. Furthermore, the new family 1 glycosyltransferase was produced in Escherichia coli and shown to efficiently catalyze galactosylation at 3-hydroxyl groups of several anthocyanidins and flavonols. These findings suggest a complex mechanism of PA accumulation in persimmon fruits.
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Affiliation(s)
- Ayako Ikegami
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502 Japan
- Laboratory of Pomology, Department of Bioproduction Sciences, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836 Japan
| | - Takashi Akagi
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502 Japan
| | - Daniel Potter
- Department of Plant Sciences, University of California, One Shields Avenue, Davis, CA 95616 USA
| | - Masahiko Yamada
- Department of Citrus Research, National Institute of Fruit Tree Science, Kuchinotsu, Nagasaki 859-2501 Japan
| | - Akihiko Sato
- Grape and Persimmon Research Station, National Institute of Fruit Tree Science, Akitsu, Hiroshima 739-2494 Japan
| | - Keizo Yonemori
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502 Japan
| | - Akira Kitajima
- Experimental Farm, Graduate School of Agriculture, Kyoto University, Takatsuki, Osaka 569-0096 Japan
| | - Kentaro Inoue
- Department of Plant Sciences, University of California, One Shields Avenue, Davis, CA 95616 USA
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Nomura K, Ikegami A, Koide A, Yagi F. Japanese chestnut (Castanea crenata) agglutinin may have a role as vegetative storage protein. J Plant Physiol 2008; 165:671-675. [PMID: 17936407 DOI: 10.1016/j.jplph.2007.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 08/06/2007] [Accepted: 08/06/2007] [Indexed: 05/25/2023]
Abstract
The expression of Japanese chestnut (Castanea crenata) agglutinin (CCA) and its mRNA was investigated in nitrogen-fertilized young potted plants and in floral organs of adult trees. Two levels of N were used: 10 and 20mM NH(4)NO(3). Both levels increased protein content in all vegetative organs, though the magnitude of the increase differed. The highest increase was observed in stems. High levels were retained in 20mM N-fertilized plants, whereas the protein content decreased at 10mM N fertilization. Expression of CCA and its mRNA was observed in young leaves and stems, and their quantities depended on the amount of N fertilizer supplied. In mature leaves, CCA was detected in the first 4 weeks, but its mRNA was undetectable throughout the experimental period. Neither CCA nor its mRNA was detected in roots. In floral organs, CCA and its mRNA were expressed throughout the flower but their quantities differed. These results suggest that CCA acts as a vegetative storage protein, which functions in temporary nitrogen reserve. The results also suggest that expression of CCA is regulated at both transcriptional and translational levels.
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Affiliation(s)
- Keiichi Nomura
- Faculty of Agriculture, Kobe University, Nada-ku, Kobe, Japan.
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Kanzaki S, Sato A, Yamada M, Utsunomiya N, Kitajima A, Ikegami A, Yonemori K. RFLP Markers for the Selection of Pollination-constant and Non-astringent (PCNA)-Type Persimmon and Examination of the Inheritance Mode of the Markers. ACTA ACUST UNITED AC 2008. [DOI: 10.2503/jjshs1.77.28] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Nomura K, Ikegami A, Koide A, Yagi F. Glutathione transferase, but not agglutinin, is a dormancy-related protein in Castanea crenata trees. Plant Physiol Biochem 2007; 45:15-23. [PMID: 17296304 DOI: 10.1016/j.plaphy.2006.12.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2006] [Accepted: 12/29/2006] [Indexed: 05/13/2023]
Abstract
The annual changes in Japanese chestnut (Castanea crenata Sieb. et Zucc.) agglutinin (CCA) were investigated by both protein and RNA blotting analyses, to clarify whether CCA has a function as storage protein. In the woody part of shoots and leaves, CCA expression was only detected at both the protein and RNA levels in May and June. In buds, the CCA protein and mRNA expressions were both restricted to April. However, the amount of accumulated CCA was too low to act as a nitrogen reserve. No expression was observed in the bark at any time point, suggesting that bark does not contain either CCA or CCA-like proteins. These results suggest that CCA may be required in young organs as a defense protein, rather than as a storage protein. In addition, CCA was not related to dormancy, unlike some other woody plant bark lectins. In contrast to CCA, a 28kDa polypeptide was observed to accumulate during dormancy. Sequence analysis indicated that this polypeptide was a glutathione transferase. After cDNA cloning, RNA blot analyses indicated that this glutathione transferase was strongly expressed in woody parts during mid-winter. In shoots, this protein represented approximately 10% of the total soluble protein content. Therefore, in Japanese chestnut trees, glutathione transferase may play a nitrogen storage role in addition to its intrinsic defensive role against stresses during dormancy.
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Affiliation(s)
- Keiichi Nomura
- Department of Plant Resource Science, Faculty of Agriculture, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.
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Ikegami A, Sato A, Yamada M, Kitajima A, Yonemori K. Molecular Size Profiles of Tannins in Persimmon Fruits of Japanese and Chinese Pollination-constant Non-astringent (PCNA)-type Cultivars and their Offspring Revealed by Size-exclusion Chromatography. ACTA ACUST UNITED AC 2005. [DOI: 10.2503/jjshs.74.437] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Ayako Ikegami
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University
| | - Akihiko Sato
- Department of Grape and Persimmon Research, National Institute of Fruit Tree Science
| | - Masahiko Yamada
- Department of Grape and Persimmon Research, National Institute of Fruit Tree Science
| | - Akira Kitajima
- Experimemtal Farm, Graduate School of Agriculture, Kyoto University
| | - Keizo Yonemori
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University
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18
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Berlanga ML, Olsen CM, Chen V, Ikegami A, Herring BE, Duvauchelle CL, Alcantara AA. Cholinergic interneurons of the nucleus accumbens and dorsal striatum are activated by the self-administration of cocaine. Neuroscience 2003; 120:1149-56. [PMID: 12927219 DOI: 10.1016/s0306-4522(03)00378-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The nucleus accumbens, a major component of the ventral striatum, and the dorsal striatum are primary targets of the mesolimbic dopamine pathway, which is a pathway that plays a critical role in reward and addiction. The shell compartment of the nucleus accumbens and the ventromedial striatum, in particular, receive extensive afferent projections from the ventral tegmental area, which is the major afferent source of the mesolimbic pathway [Prog Brain Res 99 (1993) 209; J Neurosci 7 (1987) 3915]. The present study focused on striatal cholinergic interneurons as potential key neurons involved in the neural basis of drug reinforcement. The main finding of this study is that cholinergic interneurons located in the shell compartment of the nucleus accumbens and the ventromedial striatum were activated, as measured by Fos labeling, following a 1 h session of the self-administration of cocaine in rats. A direct correlation existed between the percent of cholinergic interneurons that were activated and the amount of cocaine that was self-administered. The greatest amount of administered cocaine (approximately 10 mg/kg) resulted in the activation of approximately 80% of the cholinergic neurons. No such correlation existed in the group of animals that self-administered saline. In addition, activation was not found in the core compartment of the nucleus accumbens or the dorsolateral striatum, which receive extensive innervation from the substantia nigra and thus are more closely tied to the motor effects of the drug. In conclusion, cocaine-driven neuronal activation was specific to the shell compartment of the nucleus accumbens (R(2)=0.9365) and the ventromedial striatum (R(2)=0.9059). These findings demonstrate that cholinergic interneurons are involved in the initial stage of cocaine intake and that these neurons are located in areas of the nucleus accumbens and dorsal striatum that are more closely tied to the rewarding and hedonic effects rather than the motor effects of cocaine intake.
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Affiliation(s)
- M L Berlanga
- Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA
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19
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Yonemori K, Ikegami A, Kanzaki S, Sugiura A. UNIQUE FEATURES OF TANNIN CELLS IN FRUIT OF POLLINATION CONSTANT NON-ASTRINGENT PERSIMMONS. ACTA ACUST UNITED AC 2003. [DOI: 10.17660/actahortic.2003.601.3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Tokumasu K, Tashiro N, Ikegami A, Yoneda S, Iho K. Abnormal eye movement and nystagmus in the case of cerebellar lesion. Adv Otorhinolaryngol 2002; 30:210-3. [PMID: 12325187 DOI: 10.1159/000407641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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21
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Yates RA, Tateno M, Nairn K, Ikegami A, Dane A, Kemp J. The pharmacokinetics of the antimigraine compound zolmitriptan in Japanese and Caucasian subjects. Eur J Clin Pharmacol 2002; 58:247-52. [PMID: 12136370 DOI: 10.1007/s00228-002-0461-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2001] [Indexed: 11/26/2022]
Abstract
BACKGROUND Zolmitriptan is a 5HT(1B/1D) receptor agonist effective in the acute treatment of migraine. Clinical trials in the USA and Europe have demonstrated the optimal oral therapeutic dose to be 2.5 mg. The 2.5-mg oral tablet has recently been licensed in Japan. OBJECTIVE To compare the pharmacokinetics of zolmitriptan and its metabolites in Japanese and Caucasian subjects and evaluate the effect of gender on these pharmacokinetics in Japanese volunteers. METHODS In this open, parallel-group study, 30 Japanese and 30 Caucasian volunteers (20-45 years) received a single 2.5-mg zolmitriptan tablet in the fasting state. Blood samples were taken up to 15 h post-dose to determine plasma concentrations of zolmitriptan and its active metabolite, 183C91. Urinary excretion of zolmitriptan, 183C91 and the inactive N-oxide and indole acetic acid metabolites were measured over 24 h. RESULTS Japanese volunteers were, on average, smaller and lighter than Caucasian volunteers. Plasma-concentration profiles of zolmitriptan and 183C91 were similar in the two groups. Although geometric mean zolmitriptan and 183C91 area under the plasma concentration-time curve (AUC) and maximum plasma concentration (C(max)) were slightly higher in Japanese subjects (up to 20%), these differences were not considered to be of clinical relevance as the 90% confidence interval for the ratio of AUCs fell within pre-specified limits (0.67 to 1.5). Mean zolmitriptan and 183C91 half-lives were around 2.5 h for both populations. Urinary excretion of the four analytes was similar in Japanese and Caucasians. Plasma concentrations of zolmitriptan were higher in Japanese females than males (AUC 40% and C(max) 29% higher), consistent with the results previously obtained in Caucasians. CONCLUSION Pharmacokinetic parameters of zolmitriptan were similar between Caucasian and Japanese volunteers.
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Affiliation(s)
- R A Yates
- Clinical Pharmacology Unit, AstraZeneca Pharmaceuticals, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK.
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22
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Nakamura S, Ikegami A, Matsumura Y, Nakanishi T, Nomura K. Molecular cloning and expression of the mannose/glucose specific lectin from Castanea crenata cotyledons. J Biochem 2002; 131:241-6. [PMID: 11820938 DOI: 10.1093/oxfordjournals.jbchem.a003094] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
cDNA clones encoding a mannose/glucose specific lectin, CCA, from Castanea crenata cotyledons have been isolated and sequenced. The cloned CCA cDNA had an open reading frame of 927 bp encoding 309 amino acid residues. Compared with the amino acid sequence determined for the protein chemically, it was clarified that CCA has no signal peptide and undergoes no proteolytic cleavage as do other mannose specific Jacalin-related lectins. The coding region of CCA was introduced into an expression vector, pET-22b(+), and then transferred into Escherichia coli BL21(DE3). Although recombinant CCA (rCCA) accumulated as inclusion bodies, refolded rCCA exhibited a similar CD spectrum to nCCA and regained the hemagglutination activity. In addition, a hapten inhibition assay revealed that nCCA and rCCA showed the same specificities toward sugars and glycoproteins. On measurement by GPC-MALLS in the native state, the absolute molecular mass of nCCA was found to be 332 7 kDa, which indicated that nCCA is a decamer of identical subunits having a molecular mass of 33 kDa. The same as the natural molecule, rCCA showed a molecular mass of 320 +/- 5 kDa and was judged to also be a decamer. These results indicate that the rCCA obtained in this study is equivalent to nCCA.
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Affiliation(s)
- Sachiko Nakamura
- Graduate School of Science and Technology, Faculty of Agriculture, Kobe University, Rokkodai-chou 1, Nada-ku, Kobe 657-8501, Japan
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Ikegami A, Niwa A. A study of nurse scheduling in Japan. J Hum Ergol (Tokyo) 2001; 30:71-6. [PMID: 14564861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Scheduling nurses to staff shifts is a major problem in hospitals. The necessity of maintaining a certain level of service and skill in the makeup of every shift, while balancing the workload among the nurses involved, is incredibly difficult. It is often impossible to develop a schedule which satisfies all the requirements despite the time and resources spent in the effort. This paper summarizes all our published research on nurse scheduling to date. The difficulties realized by our two investigations in Japan are shown first, together with a resulting scheduling problem. The nurse scheduling model based on the results is then described. In this model, all constraints are divided into two essentially different types; that which maintains a certain level of skill for each shift ('shift constraints') and that which concerns the workload for each nurse ('nurse constraints'). By classifying the constraints in this manner, we can determine what is affected by a specific constraint when the constraint is not satisfied. We developed efficient algorithms while taking advantage of the structure of this model. Finally, it is shown that our algorithm can solve this problem for a 2-shift system efficiently.
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24
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Duvauchelle CL, Ikegami A, Castaneda E. Conditioned increases in behavioral activity and accumbens dopamine levels produced by intravenous cocaine. Behav Neurosci 2001. [PMID: 11142647 DOI: 10.1037//0735-7044.114.6.1156] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In vivo microdialysis, behavioral activity assessments, and a conditioned place preference (CPP) test were used to investigate dopaminergic correlates of cocaine-conditioned behaviors. Over 12 days, rats were given either intravenous cocaine (4.2 mg/kg) or saline (6 cocaine and 6 saline infusions) daily in distinctively different environments. The following day, rats were tested in the cocaine- and saline-paired environments; 48 hr later, CPP was determined. The cocaine-associated environment elicited greater nucleus accumbens dopamine (NAcc DA) levels, hyperactivity, and place preference, though the emergence of DA increases was not in synchrony with peak behavioral activation. Although conditioned behavioral effects after repeated cocaine are well documented, direct evidence of increased NAcc DA in response to a cocaine-paired environment has not been previously reported. Discrepancies with previous work are attributed to a number of methodological differences.
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Affiliation(s)
- C L Duvauchelle
- Division of Pharmacology/Toxicology, University of Texas at Austin, 78712-1074, USA.
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25
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Nakasone K, Ikegami A, Kato C, Horikoshi K. Isolation of the rpoD gene encoding the principal sigma factor of the deep-sea piezophilic bacterium Shewanella violacea strain DSS12 and its overexpression in Escherichia coli. Biosci Biotechnol Biochem 2001; 65:190-3. [PMID: 11272828 DOI: 10.1271/bbb.65.190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The gene encoding the principal a factor (rpoD) of the piezophilic bacterium Shewanella violacea was cloned and sequenced. The rpoD gene was found to encode a polypeptide consisting of 614 amino acid residues, showing 75.6 and 64.3% identity to those of Escherichia coli and Pseudomonas putida, respectively. Comparison with E. coli sigma70 and P. putida sigma70 showed that significant similarity exists in four conserved regions known to be required for promoter recognition and core binding. Using an expression plasmid harboring the rpoD gene, the S. violacea sigma70 factor was overexpressed in E. coli and successfully purified to near homogeneity.
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Affiliation(s)
- K Nakasone
- The DEEP STAR Group, Japan Marine Science and Technology Center, Kanagawa, Japan.
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26
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Nakasone K, Ikegami A, Fujii S, Kato C, Horikoshi K. Isolation and piezoresponse of the rpoA gene encoding the RNA polymerase alpha subunit from the deep-sea piezophilic bacterium Shewanella violacea. FEMS Microbiol Lett 2000; 193:261-8. [PMID: 11111034 DOI: 10.1111/j.1574-6968.2000.tb09434.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The rpoA gene encoding the alpha subunit of RNA polymerase from the deep-sea piezophilic bacterium Shewanella violacea DSS12 was cloned and sequenced. The rpoA gene was found to encode a polypeptide consisting of 329 amino acids with a molecular mass of 36238 Da. S. violacea alpha protein was expressed in a ts Escherichia coli mutant, to confirm whether the rpoA gene is functional. It complemented this mutation, indicating a chimeric RNA polymerase is assembled at the non-permissive temperature. Recombinant alpha protein was overexpressed using an expression plasmid harboring the rpoA gene and purified to near homogeneity. Primer extension analysis revealed that two transcriptional initiation sites are recognized by sigma(70) RNA polymerase. It also indicated that pressure response (piezoresponse) in the alpha operon occurred at the transcriptional level, suggesting some positive regulators may interact with the transcriptional apparatus and regulate the expression of the operon at different pressure conditions.
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Affiliation(s)
- K Nakasone
- The DEEP STAR Group, Japan Marine Science and Technology Center, Yokosuka, Kanagawa, Japan.
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27
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Abstract
In vivo microdialysis, behavioral activity assessments, and a conditioned place preference (CPP) test were used to investigate dopaminergic correlates of cocaine-conditioned behaviors. Over 12 days, rats were given either intravenous cocaine (4.2 mg/kg) or saline (6 cocaine and 6 saline infusions) daily in distinctively different environments. The following day, rats were tested in the cocaine- and saline-paired environments; 48 hr later, CPP was determined. The cocaine-associated environment elicited greater nucleus accumbens dopamine (NAcc DA) levels, hyperactivity, and place preference, though the emergence of DA increases was not in synchrony with peak behavioral activation. Although conditioned behavioral effects after repeated cocaine are well documented, direct evidence of increased NAcc DA in response to a cocaine-paired environment has not been previously reported. Discrepancies with previous work are attributed to a number of methodological differences.
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Affiliation(s)
- C L Duvauchelle
- Division of Pharmacology/Toxicology, University of Texas at Austin, 78712-1074, USA.
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Ikegami A, Nakasone K, Kato C, Nakamura Y, Yoshikawa I, Usami R, Horikoshi K. Glutamine synthetase gene expression at elevated hydrostatic pressure in a deep-sea piezophilic Shewanella violacea. FEMS Microbiol Lett 2000; 192:91-5. [PMID: 11040434 DOI: 10.1111/j.1574-6968.2000.tb09364.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
A glutamine synthetase gene (glnA) was isolated from a deep-sea piezophilic bacterium, Shewanella violacea strain DSS12. A 7.5-kb SacI fragment containing the complete glnA gene was cloned and sequenced. The glnA gene was found to encode a protein consisting of 469 amino acid residues, showing 75.0% identity to the glutamine synthetase of Escherichia coli. Primer extension analyses revealed two transcription initiation sites in glnA and expression from each site was positively regulated by pressure. Putative promoters recognized by sigma(70) and sigma(54) were identified in the region upstream of glnA. An electrophoretic mobility shift assay demonstrated that S. violacea sigma(54) specifically binds to the promoter region of glnA, suggesting that sigma(54) may play an important role in pressure-regulated transcription in this piezophilic bacterium.
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Affiliation(s)
- A Ikegami
- The DEEPSTAR Group, Japan Marine Science and Technology Center, Yokosuka, Japan
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Takahashi A, Tanaka S, Miwa Y, Yoshida H, Ikegami A, Niikawa J, Mitamura K. Involvement of calmodulin and protein kinase C in cholecystokinin release by bombesin from STC-1 cells. Pancreas 2000; 21:231-9. [PMID: 11039466 DOI: 10.1097/00006676-200010000-00003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mouse intestinal neuroendocrine tumor cell line STC-1 secretes cholecystokinin (CCK) and other hormones. We investigated the role of Ca2+, calmodulin (CaM), and protein kinase C (PKC) in the regulation of CCK release from STC-1 cells. Phorbol 12-myristate 13-acetate (TPA) significantly stimulated CCK release. Staurosporine significantly inhibited CCK release from STC-1 cells stimulated by TPA in a dose-dependent manner. The absence of extracellular calcium completely inhibited CCK release from TPA-stimulated STC-1 cells. Neurotensin did not stimulate CCK release from these cells. W-7, a CaM antagonist, reduced CCK release from STC-1 cells stimulated by bombesin in a dose-dependent manner. These findings suggest that CaM and PKC play an important role in the regulation of CCK release from STC-1 cells stimulated by bombesin.
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Affiliation(s)
- A Takahashi
- Second Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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30
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Ikegami A, Nakasone K, Fujita M, Fujii S, Kato C, Usami R, Horikoshi K. Cloning and characterization of the gene encoding RNA polymerase sigma factor sigma(54) of deep-sea piezophilic Shewanella violacea. Biochim Biophys Acta 2000; 1491:315-20. [PMID: 10760597 DOI: 10.1016/s0167-4781(00)00035-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have recently reported that a sigma(54)-like factor recognizes a DNA element, designated as region A, upstream of a pressure-regulated operon in piezophilic Shewanella violacea strain DSS12 (Nakasone et al., FEMS Microbiology Lett. 176 (1999) 351-356). In this study, we isolated and characterized the rpoN gene of this piezophilic bacterium. The rpoN gene was found to encode a putative protein consisting of 492 amino acid residues with a predicted molecular mass of 55359 Da. Significant homology was evident comparing the rpoN sequence of S. violacea with that of Escherichia coli (62.8% identity), Vibrio anguillarum (61.7% identity) and Pseudomonas putida (57.0% identity). The DNA-binding domain at the C-terminus of sigma(54) is well conserved in the case of the S. violacea rpoN gene product and the helix-turn-helix motif and the RpoN box are also present. In addition, the conserved glutamine-rich domain is present at the N-terminus. sigma(54) in S. violacea was expressed at a relatively constant level under various growth conditions as determined by both primer extension and Western blotting analyses. By means of a recombinant plasmid, a hexahistidine-tagged derivative of the sigma(54) from strain DSS12 was overexpressed in Escherichia coli and purified to near homogeneity. An electrophoretic mobility shift assay demonstrated that the purified sigma(54) protein specifically recognizes region A in the above-mentioned pressure-regulated operon.
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Affiliation(s)
- A Ikegami
- Department of Applied Chemistry, Faculty of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama, Japan
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Duvauchelle CL, Ikegami A, Asami S, Robens J, Kressin K, Castaneda E. Effects of cocaine context on NAcc dopamine and behavioral activity after repeated intravenous cocaine administration. Brain Res 2000; 862:49-58. [PMID: 10799668 DOI: 10.1016/s0006-8993(00)02091-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In two conditioning experiments, identical procedures (previously shown to produce place preferences for a cocaine-paired environment) were used to assess dopaminergic and behavioral activity correlates of cocaine reward conditioning and sensitization. In these experiments, animals received repeated injections of intravenous cocaine (4.2 mg/kgx6) or saline (0.2 mlx6) on alternating days. One group in each of these experiments ('Cocaine Cues') occupied a consistent distinctive environment during cocaine treatments and testing sessions. For the other conditioned group ('Novel'), all procedures were the same, except that the last cocaine injection was administered while animals were occupying a novel environment. During day 1 and day 6 of the cocaine treatment, behavioral activity was assessed in experiment 1 and in vivo microdialysis procedures were conducted in experiment 2. Over the course of the conditioning sessions, cocaine-induced behavioral activity (locomotion and rearing) increased significantly in the Cocaine Cues group, but not in the Novel group. In addition, cocaine-induced increases in NAcc dopamine levels were significantly greater when cocaine-experienced animals were tested in a cocaine-paired environment compared to equally experienced and cocaine-naive animals tested in a novel environment. Context-dependent behavioral sensitization is a well-documented phenomenon. The observation of a corresponding enhancement of dopamine efflux in lieu of a lengthy withdrawal period is uncommon, but can be attributed to methodological differences across studies. The present study uniquely demonstrates concurrent context-dependent potentiation of behavioral and dopaminergic responses to cocaine occurring in conjunction with cocaine reward.
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Affiliation(s)
- C L Duvauchelle
- College of Pharmacy, Division of Pharmacology/Toxicology, PHR 5.224, The University of Texas, Austin, TX, USA.
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Ikegami A, Nakasone K, Kato C, Usami R, Horikoshi K. Structural analysis of the ntrBC genes of deep-sea piezophilic Shewanella violacea. Biosci Biotechnol Biochem 2000; 64:915-8. [PMID: 10830521 DOI: 10.1271/bbb.64.915] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ntrBC genes coding for the bacterial signal-transducing protein NtrB and the bacterial enhancer-binding protein NtrC of deep-sea piezophilic Shewanella violacea were cloned and their nucleotide sequences were analyzed. The conserved regions of NtrB and those of NtrC are well conserved in the case of the ntrBC products of S. violacea.
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Affiliation(s)
- A Ikegami
- Department of Applied Chemistry, Faculty of Engineering, Toyo University, Saitama, Japan
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33
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Matsumoto K, Ogawa N, Nerome K, Numazaki Y, Kawakami Y, Shirato K, Arakawa M, Kudoh S, Shimokata K, Nakajima S, Yamakido M, Kashiwagi S, Nagatake T, Kawakami Y, Miyamoto H, Inoue H, Shirato K, Miura Y, Watanabe A, Nakai Y, Ishii M, Sakamoto M, Kudoh S, Abe S, Yamaguchi T, Arakawa M, Sega H, Shimatsu Y, Yoshimine F, Shimokata K, Masuda T, Yamamoto M, Iwata M, Nakajima S, Ito M, Takeda T, Ohsawa N, Kato M, Yamakido M, Takahashi J, Miyazawa T, Soejima R, Sasaki T, Nagatake T, Masaki H, Kashiwagi S, Ueno K, Hayashida K, Ando M, Ikegami A. Safety and Efficacy of the Neuraminidase Inhibitor Zanamivir in Treating Influenza Virus Infection in Adults: Results from Japan. Antivir Ther 1999. [DOI: 10.1177/135965359900400202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The study was carried out to evaluate the therapeutic effects of zanamivir, a highly selective, potent and specific inhibitor of influenza A and B virus neuraminidases, in adult patients with acute influenzalike illness. Patients who presented within 36 h of the onset of influenza-like symptoms were randomly assigned to receive one of three treatments, twice daily, for 5 days: 10 mg zanamivir powder for inhalation (zanamivir inhalation group), 10 mg zanamivir powder for inhalation plus 6.4 mg zanamivir nasal spray (zanamivir inhalation plus intranasal group) or placebo (placebo group). The primary end point was the time to alleviation of the three major symptoms (fever, headache and myalgia). The secondary end point was the time to alleviation of five influenza symptoms (fever, headache, myalgia, cough and sore throat). One hundred and sixteen patients with influenza-like illness were recruited to the study. No differences were observed between the two groups of patients who received zanamivir (inhalation group or inhalation plus intranasal group). Patients who received zanamivir recovered significantly faster (median 3 days to recovery) than the patients in the placebo group (median 4 days to recovery; P<0.01). Topically administered zanamivir was well tolerated. This study confirms that in adults, topically administered zanamivir is well tolerated and is effective in reducing the time to alleviation of influenza symptoms.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Y Kawakami
- First Department of Medicine, School of Medicine, Hokkaido University
| | - H Miyamoto
- Department of Respiratory Medicine, Ebetu City General Hospital
| | - H Inoue
- Third Department of Internal Medicine, Iwate Medical University, School of Medicine
| | - K Shirato
- The First Department of Internal Medicine, Tohoku University School of Medicine
| | - Y Miura
- Health Administration Center, Tohoku University
| | - A Watanabe
- Department of Respiratory Oncology and Molecular Medicine, Tohoku University
| | - Y Nakai
- Department of Internal Medicine, Sendai Kosei Hospital
| | - M Ishii
- Department of Respiratory Medicine, Sendai National Hospital
| | - M Sakamoto
- Department of Internal Medicine, Japan Red Cross Sendai Hospital
| | - S Kudoh
- The 4th Department of Internal Medicine, Nippon Medical School
| | - S Abe
- Department of Internal Medicine, Japan Self Defence Forces Central Hospital
| | - T Yamaguchi
- Department of Respiratory Medicine, JR Tokyo General Hospital
| | - M Arakawa
- Department of Medicine (II), Niigata University School of Medicine
| | - H Sega
- Department of Internal Medicine, Kouseiren Murakami General Hospital
| | - Y Shimatsu
- Department of Internal Medicine, Niigata Prefectural Shibata Hospital
| | - F Yoshimine
- Department of Internal Medicine, Niigata Prefectural Myokoh Hospital
| | - K Shimokata
- First Department of Internal Medicine, Nagoya University School of Medicine
| | - T Masuda
- Department of Internal Medicine, Nagoya National Hospital
| | - M Yamamoto
- Department of Pulmonary Medicine, Nagoya Ekisaikai Hospital
| | - M Iwata
- Department of Pulmonary Medicine, Toyota Memorial Hospital
| | - S Nakajima
- Fourth Department of Internal Medicine, Kinki University School of Medicine
| | - M Ito
- Department of Internal Medicine, National Toneyama Hospital
| | - T Takeda
- First Department of Internal Medicine, Osaka City University Medical School
| | - N Ohsawa
- First Department of Internal Medicine, Osaka Medical College
| | - M Kato
- Department of Pulmonary Medicine, National Sengokuso Hospital
| | - M Yamakido
- Second Department of Internal Medicine, Hiroshima University School of Medicine
| | - J Takahashi
- Department of Internal Medicine, Mazda Hospital
| | - T Miyazawa
- Department of Pulmonary Medicine, Hiroshima City Hospital
| | - R Soejima
- Department of Medical Social Work, Kawasaki University of Medical Welfare
| | - T Sasaki
- Third Department of Internal Medicine, Faculty of Medicine, Tottori University
| | - T Nagatake
- Department of Internal Medicine, Institute of Tropical Medicine Nagasaki University
| | - H Masaki
- Department of Internal Medicine, Aino Memorial Hospital
| | - S Kashiwagi
- Department of General Medicine, Kyushu University Hospital
| | - K Ueno
- Department of Internal Medicine, Hara Doi Hospital
| | | | - M Ando
- First Department of Internal Medicine, Kumamoto University School of Medicine
| | - A Ikegami
- Department of Internal Medicine, Kuwamizu Hospital
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34
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Abstract
A pressure-regulated operon has been cloned and sequenced from deep-sea barophilic Shewanella strains. To understand pressure-regulated mechanisms of gene expression, a regulatory element upstream of the pressure-regulated operon from Shewanella sp. strain DSS12 was studied. Regions A and B were classified by sequence analysis. A unique octamer motif, AAGGTAAG, was found to be repeated in tandem 13 times in region B. An electrophoretic mobility shift assay demonstrated that a O54-like factor recognizes region A and other unknown factors recognize region B. Different shift patterns of the protein-DNA complexes were observed when extracts of cells cultured at 0.1 MPa or 50 MPa were incubated with a DNA probe specific for region B. These results indicate that the deep-sea strain DSS12 expresses different DNA-binding factors under different pressure conditions.
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Affiliation(s)
- K Nakasone
- Japan Marine Science and Technology Center, Yokosuka, Japan
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35
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Kasugai Y, Ikegami A, Matsuo K, Ohashi M, Sukamoto T, Hosoi T, Ouchi Y, Orimo H. Effects of tibolone (Org OD14) treatment for 3 months on ovariectomy-induced osteopenia in 8-month-old rats on a low-calcium diet: preventive testing for 3 months. Bone 1998; 22:119-24. [PMID: 9477234 DOI: 10.1016/s8756-3282(97)00254-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Tibolone (Org OD14), (7alpha, 17alpha)-17-hydroxy-7-methyl-19-norpregn-5(10)-en-20-yn++ +-3-one, is a synthetic steroid with weak estrogenic, progestational, and androgenic properties. We investigated the prophylactic effects of tibolone on bone loss, bone strength, and plasma and urinary parameters in 8-month-old ovariectomized rats on a low-Ca diet. Oral administration of tibolone (0.03-3 mg/kg/day) was started immediately after ovariectomy (ovx) and continued for 3 months. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. Oral administration of tibolone (1 or 3 mg/kg/day) significantly prevented a decrease in BMD and bone ash density (bone ash weight/volume) of the global femur, and BMDs in the femoral distal and proximal regions. Also in the lumbar vertebrae, the ovx-induced reduction in BMD was prevented by tibolone (1 and 3 mg/kg/ day) treatment, resulting in a significantly higher lumbar vertebral (L-2) bone compression strength compared to the ovx control group. Neither ovx alone nor supplemented with tibolone affected the BMD or bending strength of the femoral mid-diaphysial region. Tibolone (0.03-3 mg/kg/day) significantly reduced the ovx-induced increases in serum osteocalcin level. Furthermore, tibolone inhibited an increase in the urinary hydroxyproline/creatinine, pyridinoline/creatinine, and deoxypyridinoline/creatinine ratios induced by ovx. Tibolone also reduced body weight gain and serum cholesterol level, as has been reported for estrogen. These findings indicate that tibolone prevents reduction in bone mass associated with osteopenia by reducing increased trabecular bone resorption induced by a combination of ovx and a low-Ca diet.
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Affiliation(s)
- Y Kasugai
- Department of Pharmacology, New Drug R & D Laboratory, Kanebo, Ltd., Osaka, Japan
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36
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Hayakawa M, Miyauchi H, Ikegami A, Nishida M. Elastic Constants of Zirconia Single Crystals Determined by X-ray Measurements for Polycrystals. ACTA ACUST UNITED AC 1998. [DOI: 10.2320/matertrans1989.39.268] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- M. Hayakawa
- Department of Mechanical Engineering, Tottori University
| | - H. Miyauchi
- Department of Mechanical Engineering, Tottori University
| | - A. Ikegami
- Department of Mechanical Engineering, Tottori University
| | - M. Nishida
- Department of Materials Science and Resource Engineering, Kumamoto University
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37
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Abstract
A sharp tip with high aspect ratio is required for imaging biological macromolecules by atomic force microscopy (AFM). A tip with the end radius of curvature less than 3 nm has been reproducibly fabricated by means of electron beam deposition (EBD) in a field-emission scanning electron microscope. Two-dimensional protein arrays of ferritin and catalase, prepared at air/water interface and transferred onto silicon wafer, could be imaged both in air and in water by AFM using this sharp EBD-tip in contact mode. The negative staining preparation conventionally used in the transmission electron microscopy of protein was applied and shown to be quite effective in fixing the protein arrays for the AFM imaging in air. Individual molecules of ferritin and catalase were visible in the two-dimensional arrays. Also, imaging in water of these protein arrays presented molecular images clearer than in air, due probably to the absence of the adhesion force and the resulting weak lateral force during scanning. These images convince us of the capability of this supertip for AFM studies of biological molecules under aqueous conditions.
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Affiliation(s)
- T Furuno
- Department of Physics, Keio University School of Medicine, Kanagawa, Japan.
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38
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Ikegami A, Ono I, Harada T, Ogura Y, Sumori K, Kouno K, Uchida S. [A case of fibrosarcoma of the ovary]. Nihon Sanka Fujinka Gakkai Zasshi 1996; 48:1177-9. [PMID: 8960695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- A Ikegami
- Department of Obstetrics and Gynecology, Ohme Municipal General Hospital, Tokyo
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39
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Kato C, Tamegai H, Ikegami A, Usami R, Horikoshi K. Open reading frame 3 of the barotolerant bacterium strain DSS12 is complementary with cydD in Escherichia coli: cydD functions are required for cell stability at high pressure. J Biochem 1996; 120:301-5. [PMID: 8889814 DOI: 10.1093/oxfordjournals.jbchem.a021413] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Escherichia coli strain JD518, a cydD-deficient mutant, displayed temperature-sensitive and pressure-sensitive growth. The defective cydD gene in this strain was complemented by open reading frame 3 (ORF3), previously identified in DNA from a barotolerant bacterium, strain DSS12, allowing growth of the cydD mutant under high temperature and high pressure conditions. Spectrophotometrical analysis indicated that the cytochrome bd complex which is assembled by the CydD protein was expressed in E. coli strain JD518 carrying the ORF3 gene at the same level as occurred in the wild-type strain. Our results indicate that the cydD gene functions are required for cell stability under the condition of high pressure stress in bacteria.
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Affiliation(s)
- C Kato
- DEEP STAR group, Japan Marine Science and Technology Center, Kanagawa.
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40
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Matsuse T, Ikegami A, Ohga E, Hosoi T, Oka T, Kida K, Fukayama M, Inoue S, Nagase T, Ouchi Y, Fukuchi Y. Expression of immunoreactive activin A protein in remodeling lesions associated with interstitial pulmonary fibrosis. Am J Pathol 1996; 148:707-13. [PMID: 8774126 PMCID: PMC1861725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The expression of activin A, one of the transforming growth factor-beta supergene family, was studied in various pulmonary conditions associated with interstitial pulmonary fibrosis (3 cases with diffuse alveolar damage, 6 cases with idiopathic pulmonary fibrosis, and 1 case with pulmonary fibrosis associated with rheumatoid arthritis) using immunohistochemical techniques on paraffin-embedded sections. Controls consisted of 10 cases with normal pulmonary parenchyma, and 2 cases with primary pulmonary hypertension and 1 case with secondary pulmonary hypertension were also studied. The lung specimens from normal parenchyma weakly expressed immunoreactive activin A on the bronchiolar epithelium. In marked contrast, all of the specimens from cases with diffuse alveolar damage and interstitial pulmonary fibrosis demonstrated strong expression of activin A on metaplastic epithelium, hyperplastic smooth muscle cells, desquamated cells, and alveolar macrophages. Pulmonary arteries from patients with primary or secondary pulmonary hypertension showed abundant immunoreactive activin A on smooth muscle cells. These findings suggest a potential role for this growth factor, activin A, in the pathogenesis of pulmonary tissue remodeling associated with interstitial pulmonary fibrosis.
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Affiliation(s)
- T Matsuse
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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41
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Hoshino S, Inoue S, Hosoi T, Saito T, Ikegami A, Kaneki M, Ouchi Y, Orimo H. Demonstration of isoforms of the estrogen receptor in the bone tissues and in osteoblastic cells. Calcif Tissue Int 1995; 57:466-8. [PMID: 8581881 DOI: 10.1007/bf00301952] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Expression of isoforms of estrogen receptor (ER) was examined in the bone tissues. Reverse transcriptase-polymerase chain reaction ((RT-PCR) using specific primers for rat ER cDNA was performed with total RNA from rat bone tissues. Then, we sequenced the amplified products after cloning and identified two isoforms of the ER and the wild-type ER. One of the ER mRNA isoforms did not have the region corresponding to exon 4 and the other isoform did not have the region corresponding to both exon 3 and exon 4. These isoforms were designated as ER delta 4 isoform and ER delta 3/4 isoform, respectively. The existence of these isoforms was also confirmed by ROS-17/2.8 osteoblastic osteosarcoma cells. Chloramphenicol acetyltransferase assay showed that these isoforms lost estrogen dependent transactivation activities. We suggest that the ER isoforms may play some roles in the bone metabolism in which estrogen is essential to maintain bone density.
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Affiliation(s)
- S Hoshino
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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42
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Miyata H, Yoshikawa H, Hakozaki H, Suzuki N, Furuno T, Ikegami A, Kinosita K, Nishizaka T, Ishiwata S. Mechanical measurements of single actomyosin motor force. Biophys J 1995; 68:286S-289S; discussion 289S-290S. [PMID: 7787092 PMCID: PMC1281950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
To elucidate the mechanism of force generation by actomyosin motor, a measuring system was constructed, in which an in vitro motility assay was combined with an optical trapping technique. An actin filament of several micron long was attached to a gelsolin-coated polystyrene bead, and was allowed to interact with a small number (approximately 1/1 micron actin filament) of rabbit skeletal heavy meromyosin (an active subfragment of myosin) molecules bound to a nitrocellulose-coated coverglass. The bead position was determined at 33-ms intervals. We measured the force generation event at relatively low (100-400 nM) ATP concentration so that the occurrence of individual force generation events could be detected with our time resolution. The actin-bound bead held in the optical trap moved in a stepwise manner in the direction of the actin filament only in the presence of ATP. At the trap strength of 0.3 pN/nm, the maximum size of the step was 11 nm, and the maximum force associated with the movement was 3.3 pN.
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Affiliation(s)
- H Miyata
- Department of Physics, Faculty of Science and Technology, Keio University, Yokohama, Japan
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43
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Sugahara K, Ohkita Y, Shibata Y, Yoshida K, Ikegami A. Structural studies on the hexasaccharide alditols isolated from the carbohydrate-protein linkage region of dermatan sulfate proteoglycans of bovine aorta. Demonstration of iduronic acid-containing components. J Biol Chem 1995; 270:7204-12. [PMID: 7706259 DOI: 10.1074/jbc.270.13.7204] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Five major hexasaccharide alditols were isolated from the carbohydrate-protein linkage region of bovine aorta dermatan sulfate peptidoglycans after reductive beta-elimination and subsequent chondroitinase ABC digestion. These molecules account for at least 55.3% of the total linkage region. Their structures were analyzed by enzymatic digestion in conjunction with high performance liquid chromatography, electrospray ionization mass spectrometry, and 500-MHz one- and two-dimensional 1H NMR spectroscopy. Three of these compounds have the conventional hexasaccharide core; delta HexA alpha 1-3Gal-NAc beta 1-4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl-ol. One is nonsulfated, and the other two are monosulfated on C6 or C4 of the GalNAc residue. They represent at least 6.3, 5.2, and 28.8% of the total linkage region, respectively. The other two compounds have the following hitherto unreported hexasaccharide core with an internal iduronic acid residue in common; delta HexA alpha 1-3GalNAc beta 1-4IdoA alpha 1-3Gal beta 1-3Gal beta 1-4Xyl-ol. One is monosulfated on C4 of the GalNAc, and the other is disulfated on C4 of the GalNAc and of the galactose residue substituted by the iduronic acid residue. These two compounds account for 35% of the five isolated hexasaccharide alditols and at least 4.3 and 10.7% of the total linkage region, respectively. The latter two structures form a striking contrast to the currently accepted conception that heparin, heparan sulfate, and chondroitin/dermatan sulfate share the common linkage tetrasaccharide core GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl. The biological significance of the isolated structures is discussed in relation to the biological functions and the biosynthetic mechanisms of dermatan sulfate.
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Affiliation(s)
- K Sugahara
- Department of Biochemistry, Kobe Pharmaceutical University, Japan
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44
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Inoue S, Orimo A, Hosoi T, Ikegami A, Kozaki K, Ouchi Y, Nomura S, Muramatsu M, Orimo H. Demonstration of activin-A in arteriosclerotic lesions. Biochem Biophys Res Commun 1994; 205:441-8. [PMID: 7999062 DOI: 10.1006/bbrc.1994.2685] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We previously reported that follistatin, an activin-binding protein, is produced in arteriosclerotic lesions. Here, the expression of activin-A which promotes the growth of vascular smooth muscle cells was examined in arteriosclerotic lesions of WHHL (Watanabe heritable hyperlipidemic) rabbits. Activin-A mRNA was detected in normal aorta by reverse transcriptase-polymerase chain reaction using specific primers for activin-A cDNA and was increased remarkably in arteriosclerotic lesions. In addition, using the cloned rabbit activin-A cDNA, RNA probe was prepared and in situ hybridization histochemistry was performed. Activin-A transcripts were detected abundantly in neointima of the diseased artery. Furthermore, immunohistochemistry also detected activin-A at the protein level. These observations suggest that activin-A is a cytokine expressed in arteriosclerotic lesions and might be involved in the pathogenesis of atherosclerosis.
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Affiliation(s)
- S Inoue
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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45
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Ikegami A, Inoue S, Hosoi T, Kaneki M, Mizuno Y, Akedo Y, Ouchi Y, Orimo H. Cell cycle-dependent expression of estrogen receptor and effect of estrogen on proliferation of synchronized human osteoblast-like osteosarcoma cells. Endocrinology 1994; 135:782-9. [PMID: 8033827 DOI: 10.1210/endo.135.2.8033827] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dual fluoroimmunohistochemical staining of estrogen receptor (ER) and bromodeoxyuridine was performed in a human osteoblastic osteosarcoma cell line, HOS TE85 cells. ER immunoreactivity was observed preferentially in the nuclei of the cells that were bromodeoxyuridine positive. ER expression at various phases of the cell cycle was investigated in HOS TE85 cells, which were synchronized at the G1/S phase boundary by intermittent exposure to thymidine and hydroxyurea. ER immunoreactivity became detectable in the S phase, decreased in the G2/M and G1 phases, and then reappeared in the S phase of the next cell cycle. Western blot analysis also showed that ER protein exists in these cells and increases in the S phase. Moreover, Northern blot analysis demonstrated that the expression of ER messenger RNA increases in the early S phase, gradually decreases during the progress of the cell cycle, and increases again in the S phase of the subsequent cell cycle. Interestingly, 17 beta-estradiol (10(-8) M) increased cell number and [3H]thymidine incorporation into DNA in the synchronized HOS TE85 cells, whereas this effect was not observed in the nonsynchronized HOS TE85 cells. The present studies suggest that the cell cycle-dependent regulation may contribute to the heterogeneity of ER expression in osteoblastic cells.
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Affiliation(s)
- A Ikegami
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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46
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Kaneki M, Inoue S, Hosoi T, Mizuno Y, Akedo Y, Ikegami A, Nakamura T, Shiraki M, Ito H, Suzu S. Effects of 1 alpha,25-dihydroxyvitamin D3 on macrophage colony-stimulating factor production and proliferation of human monocytic cells. Blood 1994; 83:2285-93. [PMID: 8161795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
1 alpha-25-Dihydroxyvitamin D3 [1 alpha,25(OH)2D3] stimulates the proliferation of human monocytes in vitro. In the present study, we investigated a possible role of macrophage colony-stimulating factor (M-CSF) in 1 alpha,25(OH)2D3-induced proliferation of human circulating monocytes and the effects of 1 alpha,25(OH)2D3 on M-CSF production by human monocytic cells. Both 1 alpha,25(OH)2D3 and recombinant human M-CSF increased 2.5-fold the nucleus number of human circulating monocytes on day 6 of the culture. These effects were inhibited by antihuman M-CSF antibody as well as by anti-c-fms antibody, although these antibodies themselves did not affect the nucleus number when added to control culture. These results indicated that M-CSF is required for 1 alpha,25(OH)2D3-stimulated monocyte proliferation. In addition, 1 alpha,25(OH)2D3 stimulated M-CSF secretion from human circulating monocytes. Secretion and mRNA expression of M-CSF by 12-0-tetradecanoylphorbol-13-acetate (TPA)-treated THP-1 cells (human monocytic leukemia cell line) and TPA-treated HL-60 cells (human promyelocytic leukemia cell line) were also increased by 1 alpha,25(OH)2D3. M-CSF secretion from TPA-treated THP-1 cells was increased by 1 alpha,25(OH)2D3 in a dose-dependent and metabolite-specific manner. The present study demonstrates that 1 alpha,25(OH)2D3 is a potent stimulator for M-CSF production by human monocytic cells and that the proliferative effect of 1 alpha,25(OH)2D3 on human monocytes may be attributed, at least in part, to the stimulated secretion of M-CSF.
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Affiliation(s)
- M Kaneki
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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47
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Mizuno Y, Hosoi T, Inoue S, Ikegami A, Kaneki M, Akedo Y, Nakamura T, Ouchi Y, Chang C, Orimo H. Immunocytochemical identification of androgen receptor in mouse osteoclast-like multinucleated cells. Calcif Tissue Int 1994; 54:325-6. [PMID: 8062148 DOI: 10.1007/bf00295958] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Expression of androgen receptor (AR) in mouse osteoclast-like multi-nucleated cells (OCs) was examined with immunocytochemical techniques. Murine OCs were obtained by co-culturing mouse osteoblastic cells and bone marrow cells. Three preparations of polyclonal anti-AR antibody which were raised in rabbit against different parts of the human AR were employed for the experiments. Specific staining for AR was demonstrated in the nuclei and the perinuclear area of mouse OCs. This is the first report demonstrating the presence of AR in osteoclast-like cells.
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Affiliation(s)
- Y Mizuno
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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48
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Inoue S, Orimo A, Hosoi T, Kondo S, Toyoshima H, Kondo T, Ikegami A, Ouchi Y, Orimo H, Muramatsu M. Genomic binding-site cloning reveals an estrogen-responsive gene that encodes a RING finger protein. Proc Natl Acad Sci U S A 1993; 90:11117-21. [PMID: 8248217 PMCID: PMC47933 DOI: 10.1073/pnas.90.23.11117] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Estrogen receptor (ER)-binding fragments were isolated from human genomic DNA by using a recombinant ER protein. Using one of these fragments as a probe, we have identified an estrogen-responsive gene that encodes a putative zinc finger protein. It has a RING finger motif present in a family of apparent DNA-binding proteins and is designated estrogen-responsive finger protein (efp). efp cDNA contains a consensus estrogen-responsive element at the 3' untranslated region that can act as a downstream estrogen-dependent enhancer. Moreover, efp is regulated by estrogen as demonstrated at both the mRNA and the protein level in ER-positive cells derived from mammary gland. These data suggest that efp may represent an estrogen-responsive transcription factor that mediates phenotypic expression of the diverse estrogen action. Thus, the genomic binding-site cloning may be applicable for isolation of the target genes of other transcription factors.
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Affiliation(s)
- S Inoue
- Department of Biochemistry, Saitama Medical School, Japan
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49
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Yamashita A, Ozaki A, Ikegami A, Hayashi A, Hara H, Sukamoto T, Ito K. Effects of a new diphenylpiperazine calcium antagonist, KB-2796, on cerebral ischemic neuronal damage in rats. Gen Pharmacol 1993; 24:1473-80. [PMID: 8112523 DOI: 10.1016/0306-3623(93)90438-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. The effects of KB-2796, a new diphenylpiperazine calcium antagonist, on the mitochondrial dysfunction and energy metabolism deficits were examined in the ischemic rat brain. 2. KB-2796 (30 mg/kg, p.o.), administered 60 min prior to decapitation, improved the reduced respiratory activity of mitochondria obtained from rat brain 5 min after decapitative ischemia. 3. KB-2796 (30 mg/kg, p.o.), administered 60 min prior to ischemic insult, improved both the reductions in pyruvate and ATP and prevented increases in the lactate/pyruvate ratio induced by 30-min forebrain ischemia in rats with 4-vessel occlusion (4-VO). 4. The effect of KB-2796 on local cerebral glucose utilization (LCGU) was examined by a quantitative autoradiographic 2-[14C]deoxyglucose method in normal and 4-VO rats. 5. Postischemic LCGU measured 24 hr after reperfusion in the forebrain, in particular in the cortex, thalamus, geniculate body, hippocampus, caudate-putamen, nucleus accumbens, colliculus, and corpus callosum, was below the normal control value. 6. KB-2796 (1 mg/kg, i.v.), administered 1 min prior to the injection of 2-[14C]deoxyglucose, improved the reductions in LCGU that were produced by cerebral ischemia in the cortex, thalamus, geniculate body, caudate-putamen, nucleus accumbens and substantia nigra, but did not affect LCGU in normal rats. 7. These findings suggest that KB-2796 minimized the deficits in brain energy metabolism produced by ischemia; this agent may therefore be a valuable therapeutic drug in cerebrovascular-related disorders.
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Affiliation(s)
- A Yamashita
- Department of Pharmacology, New Drug Research Laboratories, Kanebo Ltd, Osaka, Japan
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50
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Orimo A, Inoue S, Ikegami A, Hosoi T, Akishita M, Ouchi Y, Muramatsu M, Orimo H. Vascular smooth muscle cells as target for estrogen. Biochem Biophys Res Commun 1993; 195:730-6. [PMID: 7690560 DOI: 10.1006/bbrc.1993.2106] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
ER mRNA was detected as 6.0 kb band by Northern blot analysis in vascular smooth muscle cells (VSMC) derived from rat aorta. The presence of ER mRNA in VSMC was confirmed by reverse transcriptase-polymerase chain reaction using specific primers for rat ER cDNA. In addition, the immunocytochemistry of ER was performed in VSMC using a monoclonal anti-ER antibody which recognizes DNA-binding domain of ER. The immunoreactivity was distributed in the cytoplasm as well as in the nuclei. Thus, the expression of ER in VSMC was demonstrated at both the protein and the mRNA level. Furthermore, the expression of c-fos mRNA in VSMC was found up-regulated by 17 beta-estradiol treatment within 30 min. The observation that VSMC possess ER and respond to estrogen supports the idea that estrogen may directly influence vascular cell system through the ER.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Base Sequence
- Blotting, Northern
- Breast Neoplasms
- Cell Line
- Cells, Cultured
- Estradiol/pharmacology
- Female
- Gene Expression/drug effects
- Genes, fos/drug effects
- Humans
- Immunohistochemistry
- Molecular Sequence Data
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Oligodeoxyribonucleotides
- Poly A/analysis
- Poly A/metabolism
- Polymerase Chain Reaction
- RNA/analysis
- RNA/metabolism
- RNA, Messenger/analysis
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Receptors, Estrogen/analysis
- Receptors, Estrogen/biosynthesis
- Tumor Cells, Cultured
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Affiliation(s)
- A Orimo
- Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan
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