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Asano, Tomoya ; Masuda, Daisuke ; Yasuda, Michiko ; Nakashita, Hideo ; Kudo, Toshiaki ; Kimura, Makoto ; Yamaguchi, Kazuo ; Nishiuchi, Takumi
出版情報: Plant Journal.  53  pp.450-464,  2008-02-01.  Blackwell Publishing Inc
URL: http://hdl.handle.net/2297/9895
概要: 金沢大学学際科学実験センター遺伝子研究施設<br />Trichothecenes are a closely related family of phytotoxins that are produced by phytopa thogenic fungi. In Arabidopsis, expression of AtNFXL1, a homologue of the putative human transcription repressor NF-X1, was significantly induced by application of type A trichothecenes, such as T-2 toxin. An atnfxl1 mutant growing on medium lacking trichothecenes showed no phenotype, whereas a hypersensitivity phenotype was observed in T-2 toxin-treated atnfxl1 mutant plants. Microarray analysis indicated that several defense-related genes (i.e. WRKYs, NBS-LRRs, EDS5, ICS1, etc.) were upregulated in T-2 toxin-treated atnfxl1 mutants compared with wild-type plants. In addition, enhanced salicylic acid (SA) accumulation was observed in T-2 toxin-treated atnfxl1 mutants, which suggests that AtNFXL1 functions as a negative regulator of these defense-related genes via an SA-dependent signaling pathway. We also found that expression of AtNFXL1 was induced by SA and flg22 treatment. Moreover, the atnfxl1 mutant was less susceptible to a compatible phytopathogen, Pseudomonas syringae pv. tomato strain DC3000 (Pst DC3000). Taken together, these results indicate that AtNFXL1 plays an important role in the trichothecene response, as well as the general defense response in Arabidopsis. © 2007 The Authors. 続きを見る
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Higa, Arisa ; Kimura, Makoto ; Mimori, Kouhei ; Ochiai-Fukuda, Tetsuko ; Tokai, Takeshi ; Takahashi-Ando, Naoko ; Nishiuchi, Takumi ; Igawa, Tomoko ; Fujimura, Makoto ; Hamamoto, Hiroshi ; Usami, Ron ; Yamaguchi, Isamu
出版情報: Bioscience, biotechnology, and biochemistry.  67  pp.914-918,  2003-04-23.  日本農芸化学会 = Japan Society for Bioscience, Biotechnology, and Agrochemistry
URL: http://hdl.handle.net/2297/18987
概要: 金沢大学学際科学実験センター遺伝子研究施設<br />Trichothecene 3-O-acetyltransferase (encoded by Tri101) inactivates the virulence facto r of the cereal pathogen Fusarium graminearum. Zearalenone hydrolase (encoded by zhd101) detoxifies the oestrogenic mycotoxin produced by the same pathogen. These genes were introduced into a model monocotyledon rice plant to evaluate their usefulness for decontamination of mycotoxins. The strong and constitutive rice Actl promoter did not cause accumulation of TRI101 protein in transgenic rice plants. In contrast, the same promoter was suitable for transgenic production of ZHD101 protein ; so far, five promising To plants have been generated. Low transgenic expression of Tri101 was suggested to be increased by addition of an Ω enhancer sequence upstream of the start codon. 続きを見る
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Sogabe, Yusuke ; Nakamura, Haruna ; Nakagawa, Tomoyuki ; Hasegawa, Satoko ; Asano, Tomoya ; Ohta, Hiroyuki ; Yamaguchi, Kazuo ; Mueller, Martin J. ; Kodama, Hiroaki ; Nishiuchi, Takumi
出版情報: Plant Signaling and Behavior.  6  pp.119-121,  2011-07-01.  Landes Bioscience
URL: http://hdl.handle.net/2297/29198
概要: It is known that wounding systemically activates the expression of various defense-related genes in plants. However, most studies of wound-induced systemic response are concerned with a leaf-toleaf response. We have recently reported that the long distance signaling was also observed in the shoots of Arabidopsis seedling with wounded roots. We identified early and late root-to-shoot responsive (RtS) genes that were upregulated in the shoots of root-wounded seedlings at 30 min and 6 h post-injury, respectively. It is likely that the primary signals were rapidly transfered from injured roots to shoots, and then these signals were converted into chemical signals. In fact, increase of JA and OPDA content activated the expression of early and late RtS genes in shoots, respectively. In addition, we visualized wound-induced root-to-shoot response by using RtS promoter- luciferase (Luc) transgenic plants. Analysis of the AtERF13 promoter::Luc transgenic plants clearly shows that the wound-induced root-to-shoot signaling was rapidly activated via the vascular systems. © 2011 Landes Bioscience. 続きを見る
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Nishiuchi, Takumi ; Masuda, Daisuke ; Nakashita, Hideo ; Ichimura, Kazuya ; Shinozaki, Kazuo ; Yoshida, Shigeo ; Kimura, Makoto ; Yamaguchi, Isamu ; Yamaguchi, Kazuo
出版情報: Molecular Plant-Microbe Interactions.  19  pp.512-520,  2006-05-01.  American Phytopathological Society
URL: http://hdl.handle.net/2297/14524
概要: 金沢大学学際科学実験センター遺伝子研究施設<br />Phytopathogenic fungi such as Fusarium spp. synthesize trichothecene family phytotoxins . Although the type B trichothecene, deoxynivalenol (DON), is thought to be a virulence factor allowing infection of plants by their trichothecene-producing Fusarium spp., little is known about effects of trichothecenes on the defense response in host plants. Therefore, in this article, we investigated these effects of various trichothecenes in Fusarium-susceptible Arabidopsis thaliana. Necrotic lesions were observed in Arabidopsis leaves infiltrated by 1 μM type A trichothecenes such as T-2 toxin. Trichothecene-induced lesions exhibited dead cells, callose deposition, generation of hydrogen peroxide, and accumulation of salicylic acids. Moreover, infiltration by trichothecenes caused rapid and prolonged activation of two mitogen-activated protein kinases and induced expression of both PR-1 and PDF1.2 genes. Thus, type A trichothecenes trigger the cell death by activation of an elicitor-like signaling pathway in Arabidopsis. Although DON did not have such an activity even at 10 μM, translational inhibition by DON was observed at concentrations above 5 μM. These results suggested that DON is capable of inhibiting translation in Arabidopsis cells without induction of the elicitor-like signaling pathway. © 2006 The American Phytopathological Society.. 続きを見る
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Wang, Fei ; Okamoto, Yasuo ; Inoki, Isao ; Yoshioka, Kazuaki ; Du, Wa ; Qi, Xun ; Takuwa, Noriko ; Gonda, Koichi ; Yamamoto, Yasuhiko ; Ohkawa, Ryunosuke ; Nishiuchi, Takumi ; Sugimoto, Naotoshi ; Yatomi, Yutaka ; Mitsumori, Kunitoshi ; Asano, Masahide ; Kinoshita, Makoto ; Takuwa, Yoh
出版情報: The journal of clinical investigation.  120  pp.3979-3995,  2010-11-01.  American Society for Clinical Investigation
URL: http://hdl.handle.net/2297/25352
概要: 金沢大学医薬保健研究域医学系<br />Sphingosine-1-phosphate (S1P) is a biologically active sphingolipid that has pleiotropic effec ts in a variety of cell types including ECs, SMCs, and macrophages, all of which are central to the development of atherosclerosis. It may therefore exert stimulatory and inhibitory effects on atherosclerosis. Here, we investigated the role of the S1P receptor S1PR2 in atherosclerosis by analyzing S1pr2–/– mice with an Apoe–/– background. S1PR2 was expressed in macrophages, ECs, and SMCs in atherosclerotic aortas. In S1pr2–/–Apoe–/– mice fed a high-cholesterol diet for 4 months, the area of the atherosclerotic plaque was markedly decreased, with reduced macrophage density, increased SMC density, increased eNOS phosphorylation, and downregulation of proinflammatory cytokines compared with S1pr2+/+Apoe–/– mice. Bone marrow chimera experiments indicated a major role for macrophage S1PR2 in atherogenesis. S1pr2–/–Apoe–/– macrophages showed diminished Rho/Rho kinase/NF-κB (ROCK/NF-κB) activity. Consequently, they also displayed reduced cytokine expression, reduced oxidized LDL uptake, and stimulated cholesterol efflux associated with decreased scavenger receptor expression and increased cholesterol efflux transporter expression. S1pr2–/–Apoe–/– ECs also showed reduced ROCK and NF-κB activities, with decreased MCP-1 expression and elevated eNOS phosphorylation. Pharmacologic S1PR2 blockade in S1pr2+/+Apoe–/– mice diminished the atherosclerotic plaque area in aortas and modified LDL accumulation in macrophages. We conclude therefore that S1PR2 plays a critical role in atherogenesis and may serve as a novel therapeutic target for atherosclerosis. 続きを見る
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Nazifi, Ehsan ; Wada, Naoki ; Yamaba, Minami ; Asano, Tomoya ; Nishiuchi, Takumi ; Matsugo, Seiichi ; Sakamoto, Toshio
出版情報: Marine Drugs.  11  pp.3124-3154,  2013-01-01.  Ocean University of China, MDPI
URL: http://hdl.handle.net/2297/36264
概要: Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc commune (N. commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. commune. The glycosylation of porphyra-334 and palythine-threonine in N. commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments. © 2013 by the authors. 続きを見る
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Fujita, Nozomi ; Nagata, Yuka ; Nishiuchi, Takumi ; Sato, Makoto ; Iwami, Masafumi ; Kiya, Taketoshi
出版情報: Current Biology.  23  pp.2063-2070,  2013-10-21. 
URL: http://hdl.handle.net/2297/36281
概要: Many insects exhibit stereotypic instinctive behavior [1-3], but the underlying neural mechanisms are not well understood due to difficulties in detecting brain activity in freely moving animals. Immediate early genes (IEGs), such as c-fos, whose expression is transiently and rapidly upregulated upon neural activity, are powerful tools for detecting behavior-related neural activity in vertebrates [4, 5]. In insects, however, this powerful approach has not been realized because no conserved IEGs have been identified. Here, we identified Hr38 as a novel IEG that is transiently expressed in the male silkmoth Bombyx mori by female odor stimulation. Using Hr38 expression as an indicator of neural activity, we mapped comprehensive activity patterns of the silkmoth brain in response to female sex pheromones. We found that Hr38 can also be used as a neural activity marker in the fly Drosophila melanogaster. Using Hr38, we constructed a neural activity map of the fly brain that partially overlaps with fruitless (fru)-expressing neurons in response to female stimulation. These findings indicate that Hr38 is a novel and conserved insect neural activity marker gene that will be useful for a wide variety of neuroethologic studies. © 2013 Elsevier Ltd. All rights reserved. 続きを見る
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Rahman M., Mamunur ; Rahman M., Azizur ; Maki, Teruya ; Nishiuchi, Takumi ; Asano, T. ; Hasegawa, Hiroshi
出版情報: Chemosphere.  pp.213-219,  2014-01-01.  Elsevier
URL: http://hdl.handle.net/2297/36287
概要: Iron (Fe) is one of the vital limiting factors for phytoplankton in vast regions of the contemporary oceans, notably the high nutrient low chlorophyll regions. Therefore, it is apparent to be acquainted with the Fe uptake strategy of marine phytoplankton under Fe-limited condition. In the present study, marine phytoplankton Prymnesium parvum was grown under Fe-deplete (0.0025 μM) and Fe-rich (0.05 μM) conditions, and proteomic responses of the organism to Fe conditions were compared. In sodium dodecyl sulfate (SDS) gel electrophoresis, 7 proteins (16, 18, 32, 34, 75, 82, and 116 kDa) were highly expressed under Fe-deplete condition, while one protein (23 kDa) was highly expressed under Fe-rich condition. These proteins were subjected to 2-dimensional gel electrophoresis (2-D DIGE) to differentiate individual proteins, and were identified by matrix-assisted laser desorption-ionization-time of flight-mass spectrometer (MALDI-TOF-MS) analysis. The results showed that under Fe-deplete condition P. parvum increases the biosynthesis of ATP binding cassette (ABC) transporters, flagellar associated protein (FAP), and Phosphoribosylaminoimidazole-succinocarboxamide synthase. These proteins are assumed to be involved in a number of cellular biochemical processes that facilitate Fe acquisition in phytoplankton. Under Fe-deplete condition, P. parvum increases the synthesis of ribulose biphosphate carboxylase (RuBisCo), malate dehydrogenase, and two Fe-independent oxidative stress response proteins, manganese superoxide dismutase (MnSOD) and Serine threonine kinase (STK). Thus, marine phytoplankton may change their Fe acquisition strategy by altering the biosynthesis of several proteins in order to cope with Fe-limitation. © 2013 Elsevier Ltd. All rights reserved. 続きを見る
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Katayama, Natsu   ; Kato, Masahiro   ; Nishiuchi, Takumi ; Yamada, Toshihiro
出版情報: Evolution and Development.  13  pp.333-342,  2011-07-01.  Wiley-Blackwell
URL: http://hdl.handle.net/2297/29200
概要: During embryogenesis in angiosperms, the embryonic shoot and root meristems are created at opposite poles of the embryo, establishing a vertical body plan. However, the aquatic eudicot family Podostemaceae exhibits an unusual horizontal body plan, which is attributed to the loss of embryonic shoot and root meristems. To infer the embryogenetic changes responsible for the loss of these meristems, we examined the embryogenesis of three podostemads with different meristem characters, that is, Terniopsis brevis with distinct shoot and root meristems, Zeylanidium lichenoides with reduced shoot and no root meristems, and Hydrobryum japonicum with no shoot and no root meristems. In T. brevis, as in other eudicots, the putative organizing center (OC) and L1 layer (= the epidermal cell layer) arose to generate a distinct shoot meristem initial, and the hypophysis formed the putative quiescent center (QC) of a root meristem. Z. lichenoides had a morphologically unrecognizable shoot meristem, because a distinct L1 layer did not develop, whereas the putative OC precursor arose normally. In H. japonicum, the vertical divisions of the apical cells of eight-cell embryo prevented putative OC initiation. In Z. lichenoides and H. japonicum, the putative QC failed to initiate because the hypophysis repeated longitudinal divisions during early embryogenesis. Based on their phylogenetic relationships, we infer that the conventional embryonic shoot meristem was lost in Podostemaceae via two steps, that is, the loss of a distinct L1 layer and the loss of the OC, whereas the loss of the embryonic root meristem occurred once by misspecification of the hypophysis. © 2011 Wiley Periodicals, Inc. 続きを見る
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Hasegawa, Mizuho ; Imamura, Ryu ; Motani, Kou ; Nishiuchi, Takumi ; Matsumoto, Norihiko ; Kinoshita, Takeshi ; Suda, Takashi
出版情報: Journal of immunology.  182  pp.7655-7662,  2009-06-15.  American Association of Immunologists
URL: http://hdl.handle.net/2297/18477
概要: 金沢大学がん研究所<br />Apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) is an adaptor molecule that mediates inflammatory and apoptotic signals. Although the role of ASC in caspase-1-mediated IL-1beta and IL-18 maturation is well known, ASC also induces NF-kappaB activation and cytokine gene expression in human cells. In this study, we investigated the molecular mechanism and repertoire of ASC-induced gene expression in human cells. We found that the specific activation of ASC induced AP-1 activity, which was required for optimal IL8 promoter activity. ASC activation also induced STAT3-, but not STAT1-, IFN-stimulated gene factor 3- or NF-AT-dependent reporter gene expression. The ASC-mediated AP-1 activation was NF-kappaB-independent and primarily cell-autonomous response, whereas the STAT3 activation required NF-kappaB activation and was mediated by a factor that can act in a paracrine manner. ASC-mediated AP-1 activation was inhibited by chemical or protein inhibitors for caspase-8, caspase-8-targeting small-interfering RNA, and p38 and JNK inhibitors, but not by a caspase-1 inhibitor, caspase-9 or Fas-associated death domain protein (FADD) dominant-negative mutants, FADD- or RICK-targeting small-interfering RNAs, or a MEK inhibitor, indicating that the ASC-induced AP-1 activation is mediated by caspase-8, p38, and JNK, but does not require caspase-1, caspase-9, FADD, RICK, or ERK. DNA microarray analyses identified 75 genes that were induced by ASC activation. A large proportion of them was related to transcription (23%), inflammation (21%), or cell death (16%), indicating that ASC is a potent inducer of inflammatory and cell death-related genes. This is the first report of ASC-mediated AP-1 activation and the repertoire of genes induced downstream of ASC activation. 続きを見る