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81.
Hiroshi Katoh Toru Okamoto Takasuke Fukuhara Hiroto Kambara Eiji Morita Yoshio Mori Wataru Kamitani Yoshiharu Matsuura 《Journal of virology》2013,87(1):489-502
Stress granules (SGs) are cytoplasmic foci composed of stalled translation preinitiation complexes induced by environmental stress stimuli, including viral infection. Since viral propagation completely depends on the host translational machinery, many viruses have evolved to circumvent the induction of SGs or co-opt SG components. In this study, we found that expression of Japanese encephalitis virus (JEV) core protein inhibits SG formation. Caprin-1 was identified as a binding partner of the core protein by an affinity capture mass spectrometry analysis. Alanine scanning mutagenesis revealed that Lys97 and Arg98 in the α-helix of the JEV core protein play a crucial role in the interaction with Caprin-1. In cells infected with a mutant JEV in which Lys97 and Arg98 were replaced with alanines in the core protein, the inhibition of SG formation was abrogated, and viral propagation was impaired. Furthermore, the mutant JEV exhibited attenuated virulence in mice. These results suggest that the JEV core protein circumvents translational shutoff by inhibiting SG formation through an interaction with Caprin-1 and facilitates viral propagation in vitro and in vivo. 相似文献
82.
Takanori Nihira Erika Suzuki Motomitsu Kitaoka Mamoru Nishimoto Ken'ichi Ohtsubo Hiroyuki Nakai 《The Journal of biological chemistry》2013,288(38):27366-27374
A gene cluster involved in N-glycan metabolism was identified in the genome of Bacteroides thetaiotaomicron VPI-5482. This gene cluster encodes a major facilitator superfamily transporter, a starch utilization system-like transporter consisting of a TonB-dependent oligosaccharide transporter and an outer membrane lipoprotein, four glycoside hydrolases (α-mannosidase, β-N-acetylhexosaminidase, exo-α-sialidase, and endo-β-N-acetylglucosaminidase), and a phosphorylase (BT1033) with unknown function. It was demonstrated that BT1033 catalyzed the reversible phosphorolysis of β-1,4-d-mannosyl-N-acetyl-d-glucosamine in a typical sequential Bi Bi mechanism. These results indicate that BT1033 plays a crucial role as a key enzyme in the N-glycan catabolism where β-1,4-d-mannosyl-N-acetyl-d-glucosamine is liberated from N-glycans by sequential glycoside hydrolase-catalyzed reactions, transported into the cell, and intracellularly converted into α-d-mannose 1-phosphate and N-acetyl-d-glucosamine. In addition, intestinal anaerobic bacteria such as Bacteroides fragilis, Bacteroides helcogenes, Bacteroides salanitronis, Bacteroides vulgatus, Prevotella denticola, Prevotella dentalis, Prevotella melaninogenica, Parabacteroides distasonis, and Alistipes finegoldii were also suggested to possess the similar metabolic pathway for N-glycans. A notable feature of the new metabolic pathway for N-glycans is the more efficient use of ATP-stored energy, in comparison with the conventional pathway where β-mannosidase and ATP-dependent hexokinase participate, because it is possible to directly phosphorylate the d-mannose residue of β-1,4-d-mannosyl-N-acetyl-d-glucosamine to enter glycolysis. This is the first report of a metabolic pathway for N-glycans that includes a phosphorylase. We propose 4-O-β-d-mannopyranosyl-N-acetyl-d-glucosamine:phosphate α-d-mannosyltransferase as the systematic name and β-1,4-d-mannosyl-N-acetyl-d-glucosamine phosphorylase as the short name for BT1033. 相似文献
83.
Ramachandran Prakasam Mitsuaki Fujimoto Ryosuke Takii Naoki Hayashida Eiichi Takaki Ke Tan Fangxu Wu Sachiye Inouye Akira Nakai 《FEBS letters》2013
The febrile response is elicited by pyrogenic cytokines including IL-6 in response to microorganism infections and diseases in vertebrates. Mammalian HSF1, which senses elevations in temperature, negatively regulates the response by suppressing pyrogenic cytokine expression. We here showed that HSF3, an avian ortholog of mammalian HSF1, directly binds to and activates IL-6 during heat shock in chicken cells. Other components of the febrile response mechanism, such as IL-1β and ATF3, were also differently regulated in mammalian and chicken cells. These results suggest that the febrile response is exacerbated by a feed-forward circuit composed of the HSF3-IL-6 pathway in birds. 相似文献
84.
Tarô Adati Shinichi Kato Wataru Toriumi Kei Kawazu Wayan Susila Ketut Sumiartha Gede Suastika Dadang I Made Samudra 《Applied Entomology and Zoology》2013,48(2):113-118
The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest. 相似文献
85.
86.
Akira Muto Masamichi Ohkura Gembu Abe Junichi Nakai Koichi Kawakami 《Current biology : CB》2013,23(4):307-311
Download : Download video (74MB) 相似文献
87.
Chie Hashimoto Wataru Nomura Tetsuo Narumi Masayuki Fujino Toru Nakahara Naoki Yamamoto Tsutomu Murakami Hirokazu Tamamura 《Bioorganic & medicinal chemistry》2013,21(22):6878-6885
Despite almost 30 years since the identification of the human immunodeficiency virus type I (HIV-1), development of effective AIDS vaccines has been hindered by the high mutability of HIV-1. The HIV-1 co-receptors CCR5 and CXCR4 are genetically stable, but viral proteins may mutate rapidly during the course of infection. CXCR4 is a seven transmembrane G protein-coupled receptor, possessing an N-terminal region (NT) and three extracellular loops (ECL1-3). Previous studies have shown that the CXCR4-ED-derived peptides inhibit the entry of HIV-1 by interacting with gp120, an HIV-1 envelope glycoprotein. In the present study, antigenicity of CXCR4-derived peptides has been investigated and the anti-HIV-1 effects of induced antisera have been assessed. It was found that CXCR4-ED-derived antigen molecules immunize mice, showing that the linear peptides have higher antigenicity than the cyclic peptides. The L1- and L2-induced antisera inhibited the HIV-1 entry significantly, while anti-N1 antibodies have no inhibitory activity. This study produced promising examples for the design of AIDS vaccines which target the human protein and can overcome mutability of HIV-1. 相似文献
88.
Chie Hashimoto Tetsuo Narumi Hiroyuki Otsuki Yuki Hirota Hiroshi Arai Kazuhisa Yoshimura Shigeyoshi Harada Nami Ohashi Wataru Nomura Tomoyuki Miura Tatsuhiko Igarashi Shuzo Matsushita Hirokazu Tamamura 《Bioorganic & medicinal chemistry》2013,21(24):7884-7889
To date, several small molecules of CD4 mimics, which can suppress competitively the interaction between an HIV-1 envelope glycoprotein gp120 and a cellular surface protein CD4, have been reported as viral entry inhibitors. A lead compound 2 (YYA-021) with relatively high potency and low cytotoxicity has been identified previously by SAR studies. In the present study, the pharmacokinetics of the intravenous administration of compound 2 in rats and rhesus macaques is reported. The half-lives of compound 2 in blood in rats and rhesus macaques suggest that compound 2 shows wide tissue distribution and relatively high distribution volumes. A few hours after the injection, both plasma concentrations of compound 2 maintained micromolar levels, indicating it might have promise for intravenous administration when used combinatorially with anti-gp120 monoclonal antibodies. 相似文献
89.
Keiji Saito Akira Nakao Tsuyoshi Shinozuka Kousei Shimada Satoshi Matsui Kiyoshi Oizumi Kazuki Yano Keiko Ohata Daisuke Nakai Yoko Nagai Satoru Naito 《Bioorganic & medicinal chemistry》2013,21(7):1628-1642
A cell-based assay was performed for the discovery of novel bone anabolic agents. Alkaline phosphatase (ALPase) activity of ST2 cells was utilized as an indicator of osteoblastic differentiation, and thienopyridine derivative 1 was identified as a hit compound. 3-Aminothieno[2,3-b]pyridine-2-carboxamide was confirmed to be a necessary core structure for the enhancement of ALPase activity, and then optimization of the C4-substituent on the thienopyridine ring was carried out. Introduction of cyclic amino groups to the C4-position of the thienopyridine ring improved the activity. Especially, N-phenyl-homopiperazine derivatives were found to be strong enhancers of ALPase among this new series. Furthermore, 3-amino-4-(4-phenyl-1,4-diazepan-1-yl)thieno[2,3-b]pyridine-2-carboxamide (15k) was orally administered to ovariectomized (OVX) rats over 6 weeks for evaluating the effects on areal bone mineral density (aBMD), and statistically significant improvements in aBMD were observed from the dosage of 10 mg/kg/day. 相似文献
90.
Kazuo Tanaka Hiroshi Okada Wataru Ohashi Jong-Hwan Jeon Kenichi Inafuku Yoshiki Chujo 《Bioorganic & medicinal chemistry》2013,21(10):2678-2681
The influence on the efficiencies of the triplet–triplet annihilation (TTA)-supported upconversion by oxygen under biomimetic conditions was investigated. From the solution containing the dendrimer complexes based on polyhedral oligomeric silsesquioxane (POSS)-core dendrimer with the Pt complex of octaethylporphyrin (PtOEP) and anthracene in PBS, the fluorescence emission of anthracene depending on the dissolved oxygen (DO) concentrations via the TTA-supported upconversion was obtained with the excitation light at 540 nm. In particular, we observed strong emission only under hypoxic conditions. In addition, it was found that the emission intensity via TTA-supported upconversion can be reversibly regulated by the DO concentrations in the solution. 相似文献