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991.
Tetsuharu Sugimoto Chihiro Kanayama Masateru Hiyoshi Daisuke Kosumi Kazufumi Takamune 《Development, growth & differentiation》2024,66(1):66-74
We previously identified Xenopus tudor domain containing 6/Xenopus tudor repeat (Xtdrd6/Xtr), which was exclusively expressed in the germ cells of adult Xenopus laevis. Western blot analysis showed that the XTdrd6/Xtr protein was translated in St. I/II oocytes and persisted as a maternal factor until the tailbud stage. XTdrd6/Xtr has been reported to be essential for the translation of maternal mRNA involved in oocyte meiosis. In the present study, we examined the distribution of the XTdrd6/Xtr protein during oogenesis and early development, to predict the time point of its action during development. First, we showed that XTdrd6/Xtr is localized to germinal granules in the germplasm by electron microscopy. XTdrd6/Xtr was found to be localized to the origin of the germplasm, the mitochondrial cloud of St. I oocytes, during oogenesis. Notably, XTdrd6/Xtr was also found to be localized around the nuclear membrane of St. I oocytes. This suggests that XTdrd6/Xtr may immediately interact with some mRNAs that emerge from the nucleus and translocate to the mitochondrial cloud. XTdrd6/Xtr was also detected in primordial germ cells and germ cells throughout development. Using transgenic Xenopus expressing XTdrd6/Xtr with a C-terminal FLAG tag produced by homology-directed repair, we found that the zygotic translation of the XTdrd6/Xtr protein began at St. 47/48. As germ cells are surrounded by gonadal somatic cells and are considered to enter a new differentiation stage at this phase, the newly synthesized XTdrd6/Xtr protein may regulate the translation of mRNAs involved in the new steps of germ cell differentiation. 相似文献
992.
Keizo Nishikawa Shigeto Seno Toshitada Yoshihara Ayako Narazaki Yuki Sugiura Reito Shimizu Junichi Kikuta Reiko Sakaguchi Norio Suzuki Norihiko Takeda Hiroaki Semba Masamichi Yamamoto Daisuke Okuzaki Daisuke Motooka Yasuhiro Kobayashi Makoto Suematsu Haruhiko Koseki Hideo Matsuda Masayuki Yamamoto Seiji Tobita Yasuo Mori Masaru Ishii 《EMBO reports》2021,22(12)
Oxygen plays an important role in diverse biological processes. However, since quantitation of the partial pressure of cellular oxygen in vivo is challenging, the extent of oxygen perturbation in situ and its cellular response remains underexplored. Using two‐photon phosphorescence lifetime imaging microscopy, we determine the physiological range of oxygen tension in osteoclasts of live mice. We find that oxygen tension ranges from 17.4 to 36.4 mmHg, under hypoxic and normoxic conditions, respectively. Physiological normoxia thus corresponds to 5% and hypoxia to 2% oxygen in osteoclasts. Hypoxia in this range severely limits osteoclastogenesis, independent of energy metabolism and hypoxia‐inducible factor activity. We observe that hypoxia decreases ten‐eleven translocation (TET) activity. Tet2/3 cooperatively induces Prdm1 expression via oxygen‐dependent DNA demethylation, which in turn activates NFATc1 required for osteoclastogenesis. Taken together, our results reveal that TET enzymes, acting as functional oxygen sensors, regulate osteoclastogenesis within the physiological range of oxygen tension, thus opening new avenues for research on in vivo response to oxygen perturbation. 相似文献
993.
Temporal and spatial changes in gene expression,metabolite accumulation and phytohormone content in rice seedlings grown under drought stress conditions 下载免费PDF全文
Daisuke Todaka Yu Zhao Takuya Yoshida Madoka Kudo Satoshi Kidokoro Junya Mizoi Ken‐Suke Kodaira Yumiko Takebayashi Mikiko Kojima Hitoshi Sakakibara Kiminori Toyooka Mayuko Sato Alisdair R. Fernie Kazuo Shinozaki Kazuko Yamaguchi‐Shinozaki 《The Plant journal : for cell and molecular biology》2017,90(1):61-78
994.
Yoshikazu Watanabe Kohei Hayashida Daisuke Saito Toshihiro Takahashi Junichi Sakai Eriko Nakata Takashi Kanda Takashi Iwai Shigeto Hirayama Hideaki Fujii Tomio Yamakawa Hiroshi Nagase 《Bioorganic & medicinal chemistry letters》2017,27(15):3495-3498
We designed and synthesized novel δ opioid receptor (DOR) agonists 3a–i with an azatricyclodecane skeleton, which was a novel structural class of DOR agonists. Among them, 3b exhibited high values of binding affinity and potent agonistic activity for the DOR that were approximately equivalent to those of 2 which bore an oxazatricyclodecane skeleton. In vitro assays using the blood-brain barrier (BBB) permeability test kit supported the idea that 3b achieved an excellent BBB permeability by converting an oxygen atom of 2 to a carbon atom (methylene group) in the core skeleton. As a result, 3b showed potent antinociceptive effects. 相似文献
995.
Yoshiyuki Manabe Satomi Kasahara Yohei Takakura Xiaoxiao Yang Shinji Takamatsu Yoshihiro Kamada Eiji Miyoshi Daisuke Yoshidome Koichi Fukase 《Bioorganic & medicinal chemistry》2017,25(11):2844-2850
We developed α1,6-fucosyltransferase (FUT8) inhibitors through a diversity-oriented synthesis. The coupling reaction between the fucose unit containing alkyne and the guanine unit containing sulfonyl azide under various conditions afforded a series of Guanosine 5′-diphospho-β-l-fucose (GDP-fucose) analogs. The synthesized compounds displayed FUT8 inhibition activity. A docking study revealed that the binding mode of the inhibitor synthesized with FUT8 was similar to that of GDP-fucose. 相似文献
996.
Factors affecting masticatory function of community‐dwelling older people: Investigation of the differences in the relevant factors for subjective and objective assessment 下载免费PDF全文
997.
Daisuke Uesugi Kei Shimoda Naoji Kubota Shin-ichi Ozaki Naoki Nagatani 《Bioscience, biotechnology, and biochemistry》2017,81(2):226-230
The stilbene compound resveratrol was glycosylated to give its 4′-O-β-D-glucoside as the major product in addition to its 3-O-β-D-glucoside by a plant glucosyltransferase from Phytolacca americana expressed in recombinant Escherichia coli. This enzyme transformed pterostilbene to its 4′-O-β-D-glucoside, and converted pinostilbene to its 4′-O-β-D-glucoside as a major product and its 3-O-β-D-glucoside as a minor product. An analysis of antioxidant capacity showed that the above stilbene glycosides had lower oxygen radical absorbance capacity (ORAC) values than those of the corresponding stilbene aglycones. The 3-O-β-D-glucoside of resveratrol showed the highest ORAC value among the stilbene glycosides tested, and pinostilbene had the highest value among the stilbene compounds. The tyrosinase inhibitory activities of the stilbene aglycones were improved by glycosylation; the stilbene glycosides had higher activities than the stilbene aglycones. Resveratrol 3-O-β-D-glucoside had the highest tyrosinase inhibitory activity among the stilbene compounds tested. 相似文献
998.
Exclusion of assembled MreB by anionic phospholipids at cell poles confers cell polarity for bidirectional growth 下载免费PDF全文
Takuma Kawazura Kanon Matsumoto Koki Kojima Fumiya Kato Tomomi Kanai Hironori Niki Daisuke Shiomi 《Molecular microbiology》2017,104(3):472-486
Cell polarity determines the direction of cell growth in bacteria. MreB actin spatially regulates peptidoglycan synthesis to enable cells to elongate bidirectionally. MreB densely localizes in the cylindrical part of the rod cell and not in polar regions in Escherichia coli. When treated with A22, which inhibits MreB polymerization, rod‐shaped cells became round and MreB was diffusely distributed throughout the cytoplasmic membrane. A22 removal resulted in restoration of the rod shape. Initially, diffuse MreB started to re‐assemble, and MreB‐free zones were subsequently observed in the cytoplasmic membrane. These MreB‐free zones finally became cell poles, allowing the cells to elongate bidirectionally. When MreB was artificially located at the cell poles, an additional pole was created, indicating that artificial localization of MreB at the cell pole induced local peptidoglycan synthesis. It was found that the anionic phospholipids (aPLs), phosphatidylglycerol and cardiolipin, which were enriched in cell poles preferentially interact with monomeric MreB compared with assembled MreB in vitro. MreB tended to localize to cell poles in cells lacking both aPLs, resulting in production of Y‐shaped cells. Their findings indicated that aPLs exclude assembled MreB from cell poles to establish cell polarity, thereby allowing cells to elongate in a particular direction. 相似文献
999.
Saeko Hamaoka Yoshifumi Naito Hideya Katoh Masaru Shimizu Mao Kinoshita Koichi Akiyama Atsushi Kainuma Kiyoshi Moriyama Ken J. Ishii Teiji Sawa 《Microbiology and immunology》2017,61(2):64-74
Vaccination against the type III secretion system of P. aeruginosa is a potential prophylactic strategy for reducing the incidence and improving the poor prognosis of P. aeruginosa pneumonia. In this study, the efficacies of three different adjuvants, Freund's adjuvant (FA), aluminum hydroxide (alum) and CpG oligodeoxynucleotide (ODN), were examined from the viewpoint of inducing PcrV‐specific immunity against virulent P. aeruginosa. Mice that had been immunized intraperitoneally with recombinant PcrV formulated with one of the above adjuvants were challenged intratracheally with a lethal dose of P. aeruginosa. The PcrV–FA immunized group attained a survival rate of 91%, whereas the survival rates of the PcrV–alum and PcrV–CpG groups were 73% and 64%, respectively. In terms of hypothermia recovery after bacterial instillation, PcrV–alum was the most protective, followed by PcrV–FA and PcrV–CpG. The lung edema index was lower in the PcrV–CpG vaccination group than in the other groups. PcrV–alum immunization was associated with the greatest decrease in myeloperoxidase in infected lungs, and also decreased the number of lung bacteria to a similar number as in the PcrV–FA group. There was less neutrophil recruitment in the lungs of mice vaccinated with PcrV–alum or PcrV–CpG than in those of mice vaccinated with PcrV–FA or PcrV alone. Overall, in terms of mouse survival the PcrV–CpG vaccine, which could be a relatively safe next‐generation vaccine, showed a comparable effect to the PcrV–alum vaccine. 相似文献
1000.
Nobuhiro Akuzawa Makoto Kurabayashi Tsukasa Suzuki Daisuke Yoshinari Mitsunobu Kobayashi Yoshifumi Tanahashi Fujio Makita Ryusei Saito 《Diagnostic pathology》2017,12(1):74