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991.
Escherichia coli alkaline phosphatase (AP) and human lysozyme (h-LYZ), which contain two and four disulfide bonds, respectively, were expressed in a cell-free protein synthesis system constructed from Spodoptera frugiperda 21 (Sf21) cells. AP was expressed in a soluble and active form using the insect cell-free system under non-reducing conditions, and h-LYZ was expressed in a soluble and active form under non-reducing conditions after addition of reduced glutathione (GSH), oxidized glutathione (GSSG), and protein disulfide isomerase (PDI). The in vitro synthesized proteins were purified by means of a Strep-tag attached to their C termini. Approximately 41 microg AP and 30 microg h-LYZ were obtained from 1 mL each of the reaction mixture. The efficiency of protein synthesis approached that measured under reducing conditions. Analysis of the disulfide bond arrangements by MALDI-TOF MS showed that disulfide linkages identical to those observed in the wild-type proteins were formed. 相似文献
992.
Suzuki S Ono R Narita T Pask AJ Shaw G Wang C Kohda T Alsop AE Marshall Graves JA Kohara Y Ishino F Renfree MB Kaneko-Ishino T 《PLoS genetics》2007,3(4):e55
Among mammals, only eutherians and marsupials are viviparous and have genomic imprinting that leads to parent-of-origin-specific differential gene expression. We used comparative analysis to investigate the origin of genomic imprinting in mammals. PEG10 (paternally expressed 10) is a retrotransposon-derived imprinted gene that has an essential role for the formation of the placenta of the mouse. Here, we show that an orthologue of PEG10 exists in another therian mammal, the marsupial tammar wallaby (Macropus eugenii), but not in a prototherian mammal, the egg-laying platypus (Ornithorhynchus anatinus), suggesting its close relationship to the origin of placentation in therian mammals. We have discovered a hitherto missing link of the imprinting mechanism between eutherians and marsupials because tammar PEG10 is the first example of a differentially methylated region (DMR) associated with genomic imprinting in marsupials. Surprisingly, the marsupial DMR was strictly limited to the 5′ region of PEG10, unlike the eutherian DMR, which covers the promoter regions of both PEG10 and the adjacent imprinted gene SGCE. These results not only demonstrate a common origin of the DMR-associated imprinting mechanism in therian mammals but provide the first demonstration that DMR-associated genomic imprinting in eutherians can originate from the repression of exogenous DNA sequences and/or retrotransposons by DNA methylation. 相似文献
993.
Maeda Yoshiaki Kobayashi Ryosuke Watanabe Kahori Yoshino Tomoko Bowler Chris Matsumoto Mitsufumi Tanaka Tsuyoshi 《Marine biotechnology (New York, N.Y.)》2022,24(4):788-800
Marine Biotechnology - Microalgae including diatoms are of interest for environmentally friendly manufacturing such as production of biofuels, chemicals, and materials. The highly oil-accumulating... 相似文献
994.
Kijima Yusuke Wantong Wang Igarashi Yoji Yoshitake Kazutoshi Asakawa Shuichi Suzuki Yutaka Watabe Shugo Kinoshita Shigeharu 《Marine biotechnology (New York, N.Y.)》2022,24(5):895-910
Marine Biotechnology - Most mammals, including humans, show obvious aging phenotypes, for example, loss of tissue plasticity and sarcopenia. In this regard, fish can be attractive models to study... 相似文献
995.
996.
997.
Akihiro Hirata Yoko Miyamoto Akihisa Kaneko Hiroki Sakai Kyoko Yoshizaki Tokuma Yanai Takako Miyabe‐Nishiwaki Juri Suzuki 《Journal of medical primatology》2019,48(2):137-140
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques. 相似文献
998.
Photosynthesis Research - Recently, microalgae have attracted attention as sources of biomass energy. However, fatty acids from the microalgae are mainly unsaturated and show low stability in... 相似文献
999.
Nagao Ryo Ueno Yoshifumi Akita Fusamichi Suzuki Takehiro Dohmae Naoshi Akimoto Seiji Shen Jian-Ren 《Photosynthesis research》2019,140(2):141-149
Photosynthesis Research - Diatoms are dominant phytoplankton in aquatic environments and have unique light-harvesting apparatus, fucoxanthin chlorophyll a/c-binding protein (FCP). Diatom... 相似文献
1000.
Kenichi Sugawara Shigeo Tanabe Tomotaka Suzuki Toshio Higashi 《Somatosensory & motor research》2019,36(2):109-115
Voluntary motor drive is an important central command that descends via the corticospinal tract to initiate muscle contraction. When electrical stimulation (ES) is applied to an antagonist or agonist muscle, it changes the agonist muscle’s representative motor cortex and thus its voluntary motor drive. In this study, we used a reaction time task to compare the effects of weak and strong ES of the antagonist or agonist muscle during the premotor period of a wrist extension. We recorded motor evoked potentials (MEPs) induced by transcranial magnetic stimulation (TMS) that was applied to the extensor carpi radialis (ECR; agonist) and flexor carpi radialis (FCR; antagonist). When stronger ES intensities were applied to the antagonist, the MEP control ratio in the ECR significantly increased during the premotor time. Furthermore, the MEP control ratio with stronger antagonist ES intensity was significantly larger than that in the agonist for the same ES intensity. In the FCR, the MEP control ratio was also significantly greater at the strong ES intensity than at the weak ES intensity. Furthermore, the MEP control ratio in the antagonist with a strong ES intensity was significantly larger than that in the agonist with the same ES intensity. These results suggest that agonist corticomotor excitability might be enhanced by ES of the antagonist, which in turn strongly activates the descending motor system in the preparation of agonist contraction. 相似文献