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31.
Natsuko Izumi Shinpei Kawaoka Satoshi Yasuhara Yutaka Suzuki Sumio Sugano Susumu Katsuma Yukihide Tomari 《RNA (New York, N.Y.)》2013,19(7):896-901
PIWI-interacting RNAs (piRNAs) defend the genome against transposon activity in animal gonads. The Hsp90 chaperone machinery has been implicated in the piRNA pathway, but its exact role remains obscure. Here, we examined the effect of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90-specific inhibitor, on the piRNA pathway. In the silkworm ovary-derived BmN4 cells, 17-AAG treatment reduced the level of piRNAs and PIWI proteins. In vitro, the 5′-nucleotide preference upon precursor piRNA loading was compromised by 17-AAG, whereas 3′-end trimming and 2′-O-methylation were unaffected. Our data highlight a role of Hsp90 in accurate loading of precursor piRNAs into PIWI proteins. 相似文献
32.
Tomoyuki Miyashita Shinya Neri Hiroko Hashimoto Asami Akutsu Masato Sugano Satoshi Fujii Atsushi Ochiai Genichiro Ishii 《Journal of cellular physiology》2020,235(10):7251-7260
To clear whether podoplanin-positive cancer stem cells in squamous cell carcinoma have higher invasion activity during a fibroblasts-dependent invasion. A collagen gel invasion assay was performed using fluorescent ubiquitination-based cell cycle indicator-labeled A431 cells. The total number and number of invading cells in S/G2/M phase were counted using time-lapse imaging cocultured with fibroblasts. There was no significant difference between the number of invading podoplanin-positive and negative A431 cells when fibroblasts did not exist. On the contrary, the number of invading podoplanin-positive cells was significantly higher when fibroblasts existed. The frequency of cells in S/G2/M phase among invasion was no difference. Knockdown of podoplanin decreased the number of invaded A431 cells significantly when fibroblasts existed. Podoplanin-positive A431 cells display higher invasion activity when fibroblasts exist, suggesting that some biological functions of cancer stem cells might become evident only within the fibrous tumor microenvironment. 相似文献
33.
Gamal El-Ghazaly Sumio Nakamura Yuichi Takahashi Mauro Cresti Bjöorn Walles Claudio Milanesi 《Grana》2013,52(6):369-374
The major allergen Bet ver 1 of Betula pendula (= B. verrucosa) pollen grains has been localized by gold labelling with monoclonal antibodies. The allergen is located predominantly in the starch grains and to a slight extent in the exine and intine. The possibility that environmental factors might influence the liberation of allergenic compounds present in birch pollen grains is discussed. 相似文献
34.
The biosyntheses of sescandelin (1) and sescandelin B (2) were studied by feeding of [13C]labelled precursors to Sesquicilium candelabrum. The labelling pattern of those compounds enriched from the [1-13C], [2-13C], and [l,2-13C]acetates, and from the [13C]formate showed that both compounds were derived from a pentaketide chain and a C1 unit. The isocoumarin skeleton of 1 and 2 is considered to have been formed by the cyclization of a pentaketide chain and a C1 unit, and of a pentaketide, respectively. 相似文献
35.
36.
Shigetaka Okada Sumio Kitahata Masataka Higashihara Juichiro Fukumoto 《Bioscience, biotechnology, and biochemistry》2013,77(9):1407-1415
Oligosaccharides terminated by radioactive sucrose at the reducing end of maltooligosaccharides have been used in the oligosaccharide mapping procedure for characterizing α-amylases. The action patterns of ten α-amylases from various origins were investigated with this mapping method and compared with the results with normal maltooligosaccharides. The experimental results indicated that Bacillus subtilis saccharifying, Endomycopsis and pancreatic α-amylases had similar action patterns toward oligosaccharides with or without fructose at the reducing end. However, the action patterns of other seven α-amylases were somewhat different. 相似文献
37.
38.
Saburo Tamura Ching-Fun Chang Akinori Suzuki Sumio Kumai 《Bioscience, biotechnology, and biochemistry》2013,77(3):391-397
Two new isoflavonoids were isolated from red clover as germination inhibitors for the same plant and their structures were determined as a glucoside of biochanin A (7-d-β-glucosyl-5,7-dihydroxy-4′-methoxyisoflavone) (II) and its 5-malonate (I), respectively. Besides these compounds the following substances were also isolated as inhibitors: trifolirhizin (III), ononin (IV), daidzein (V) and its 7-glucoside (VI), formononetin (VII), genistein (VIII) and biochanin A (IX). 相似文献
39.
Yukio Furuichi Takao Takahashi Katsumi Imaizumi Michihiro Sugano 《Bioscience, biotechnology, and biochemistry》2013,77(7):1777-1781
The absorbability of polyethylene glycol (PEG), a water-soluble nutritional marker, from the gastrointestinal tract of rat was examined using the [14C]-labeled compound ([14C]PEG) having a molecular weight of 4000. Intravenously injected [14C]PEG was readily excreted and recovered almost completely in the urine and neither hepatic nor renal uptake of the PEG was observed. Intragastrically administered [14C]PEG was eliminated in the urine with an average recovery of only 0.43 ± 0.13% (Mean ± S.D., n= 10) of the dose over 24 hr. From the gel column chromatographic profile of the radioactivity excreted in the urine after an oral dose, [14C]PEG was suggested to be absorbed in two forms, as an original form and as a low molecular weight component. The latter component might be the degraded product of PEG in the gastrointestinal tract. From these results it was confirmed that PEG with a molecular weight of 4000 is a satisfactory marker because of its low absorbability. 相似文献
40.
Akiko Shibui Ayako Takamori Mohammed E.M. Tolba Aya Nambu Eri Shimura Sachiko Yamaguchi Chizu Sanjoba Hajime Suto Katsuko Sudo Ko Okumura Sumio Sugano Hideaki Morita Hirohisa Saito Kenji Matsumoto Susumu Nakae 《Biochemistry and Biophysics Reports》2016
IL-25, IL-33 and TSLP, which are produced predominantly by epithelial cells, can induce production of Th2-type cytokines such as IL-4, IL-5 and/or IL-13 by various types of cells, suggesting their involvement in induction of Th2-type cytokine-associated immune responses. It is known that Th2-type cytokines contribute to host defense against malaria parasite infection in mice. However, the roles of IL-25, IL-33 and TSLP in malaria parasite infection remain unclear. Thus, to elucidate this, we infected wild-type, IL-25?/?, IL-33?/? and TSLP receptor (TSLPR)?/? mice with Plasmodium berghei (P. berghei) ANKA, a murine malaria strain. The expression levels of IL-25, IL-33 and TSLP mRNA were changed in the brain, liver, lung and spleen of wild-type mice after infection, suggesting that these cytokines are involved in host defense against P. berghei ANKA. However, the incidence of parasitemia and survival in the mutant mice were comparable to in the wild-type mice. These findings indicate that IL-25, IL-33 and TSLP are not critical for host defense against P. berghei ANKA. 相似文献