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981.
Shimizu T Hirai Y Murayama C Miyamoto A Miyazaki H Miyazaki K 《Biochemical and biophysical research communications》2011,412(1):132-135
Circadian Clock genes are associated with the estrous cycle in female animals. Treatment with Per2 and Clock siRNAs decreased the number of granulosa cells and LHr expression in follicle-stimulating hormone FSH-treated granulosa cells. Per2 siRNA treatment did not stimulate the production of estradiol and expression of P450arom, whereas Clock siRNA treatment inhibited the production of estradiol and expression of P450arom mRNA. Per2 and Clock siRNA treatment increased and unchanged, respectively, progesterone production in FSH-treated granulosa cells. Similarly, expression of StAR mRNA was increased by Per2 siRNA and unchanged by Clock siRNA. Our data provide a new insight that Per2 and Clock have different action on ovarian granulosa cell functions. 相似文献
982.
Jin B Kawai Y Hara T Takeda S Seki S Nakata Y Matsukawa K Koshimoto C Kasai M Edashige K 《Biology of reproduction》2011,85(4):834-847
The permeability of cells is important for cryopreservation. Previously, we showed in mice that the permeability to water and cryoprotectants of oocytes and embryos at early cleavage stages (early embryos) is low because these molecules move across the plasma membrane predominantly by simple diffusion through the lipid bilayer, whereas permeability of morulae and blastocysts is high because of a water channel, aquaporin 3 (AQP3). In this study, we examined the pathways for the movement of water and cryoprotectants in bovine oocytes/embryos and the role of AQP3 in the movement by determining permeability, first in intact bovine oocytes/embryos, then in bovine morulae with suppressed AQP3 expression, and finally in mouse oocytes expressing bovine AQP3. Results suggest that water moves through bovine oocytes and early embryos slowly by simple diffusion, as is the case in mice, although channel processes are also involved in the movement. On the other hand, water appears to move through morulae and blastocysts predominantly by facilitated diffusion via channels, as in mice. Like water, cryoprotectants appear to move through bovine oocytes/early embryos mostly by simple diffusion, but channel processes could also be involved in the movement of glycerol and ethylene glycol, unlike that in mice. In bovine morulae, although glycerol and ethylene glycol would move predominantly by facilitated diffusion, mostly through AQP3, as in mice, dimethylsulfoxide appears to move predominantly by simple diffusion, unlike in mice. These results indicate that permeability-related properties of bovine oocytes/embryos are similar to those of mouse oocytes/embryos, but species-specific differences do exist. 相似文献
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986.
Nobuaki Ozeki Naoko Hase Taiki Hiyama Hideyuki Yamaguchi Rie Kawai Ayami Kondo Kazuhiko Nakata Makio Mogi 《Experimental cell research》2014
We previously established a method for differentiating induced pluripotent stem cells and embryonic stem (ES) cells into α2 integrin-positive odontoblast-like cells. We also reported that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-3-regulated cell proliferation and suppresses apoptosis in these cells, suggesting that MMP-3 plays a potentially unique physiological role in the regeneration of odontoblast-like cells. Here, we examined whether up-regulation of MMP-3 activity by IL-1β was mediated by Wnt signaling and led to increased proliferation of odontoblast-like cells. IL-1β increased mRNA and protein levels of Wnt5a, Wnt5b and the Wnt receptor Lrp5. Exogenous Wnt5a and Wnt5b were found to increase MMP-3 mRNA, protein and activity, and interestingly the rate of proliferation in these cells. Treatment with siRNAs against Wnt5a, Wnt5b and Lrp5 suppressed the IL-1β-induced increase in MMP-3 expression and suppressed cell proliferation, an effect rescued by application of exogenous Wnt5. These results demonstrate the sequential involvement of Wnt5, Lrp5 and MMP-3 in effecting IL-1β-induced proliferation of ES cell-derived odontoblast-like cells. 相似文献
987.
Naoko Nakano Kota Maeyama Nobuo Sakata Fumiko Itoh Ryosuke Akatsu Miki Nakata Yuki Katsu Souichi Ikeno Yoko Togawa Thanh Thao Vo Nguyen Yukihide Watanabe Mitsuyasu Kato Susumu Itoh 《The Journal of biological chemistry》2014,289(18):12680-12692
Transforming growth factor (TGF)-β signaling is deliberately regulated at multiple steps in its pathway from the extracellular microenvironment to the nucleus. However, how TGF-β signaling is activated or attenuated is not fully understood. We recently identified transmembrane prostate androgen-induced RNA (TMEPAI), which is involved in a negative feedback loop of TGF-β signaling. When we searched for a family molecule(s) for TMEPAI, we found C18ORF1, which, like TMEPAI, possesses two PY motifs and one Smad-interacting motif (SIM) domain. As expected, C18ORF1 could block TGF-β signaling but not bone morphogenetic protein signaling. C18ORF1 bound to Smad2/3 via its SIM and competed with the Smad anchor for receptor activation for Smad2/3 binding to attenuate recruitment of Smad2/3 to the TGF-β type I receptor (also termed activin receptor-like kinase 5 (ALK5)), in a similar fashion to TMEPAI. Knockdown of C18ORF1 prolonged duration of TGF-β-induced Smad2 phosphorylation and concomitantly potentiated the expression of JunB, p21, and TMEPAI mRNAs induced by TGF-β. Consistently, TGF-β-induced cell migration was enhanced by the knockdown of C18ORF1. These results indicate that the inhibitory function of C18ORF1 on TGF-β signaling is similar to that of TMEPAI. However, in contrast to TMEPAI, C18ORF1 was not induced upon TGF-β signaling. Thus, we defined C18ORF1 as a surveillant of steady state TGF-β signaling, whereas TMEPAI might help C18ORF1 to inhibit TGF-β signaling in a coordinated manner when cells are stimulated with high levels of TGF-β. 相似文献
988.
Difference in cesium accumulation among rice cultivars grown in the paddy field in Fukushima Prefecture in 2011 and 2012 总被引:1,自引:0,他引:1
Yoshihiro Ohmori Yayoi Inui Masataka Kajikawa Atsumi Nakata Naoyuki Sotta Koji Kasai Shimpei Uraguchi Nobuhiro Tanaka Sho Nishida Takahiro Hasegawa Takuya Sakamoto Yuko Kawara Kayoko Aizawa Haruka Fujita Ke Li Naoya Sawaki Koshiro Oda Ryuichiro Futagoishi Takahiro Tsusaka Satomi Takahashi Junpei Takano Shinji Wakuta Akira Yoshinari Masataka Uehara Shigeki Takada Hayato Nagano Kyoko Miwa Izumi Aibara Takuya Ojima Kaoru Ebana Satoru Ishikawa Kuni Sueyoshi Hiroshi Hasegawa Tetsuro Mimura Mari Mimura Natsuko I. Kobayashi Jun Furukawa Daisuke Kobayashi Toshiyasu Okouchi Keitaro Tanoi Toru Fujiwara 《Journal of plant research》2014,127(1):57-66
After the accident of the Fukushima 1 Nuclear Power Plant in March 2011, radioactive cesium was released and paddy fields in a wide area including Fukushima Prefecture were contaminated. To estimate the levels of radioactive Cs accumulation in rice produced in Fukushima, it is crucial to obtain the actual data of Cs accumulation levels in rice plants grown in the actual paddy field in Fukushima City. We herein conducted a two-year survey in 2011 and 2012 of radioactive and non-radioactive Cs accumulation in rice using a number of rice cultivars grown in the paddy field in Fukushima City. Our study demonstrated a substantial variation in Cs accumulation levels among the cultivars of rice. 相似文献
989.
Emmanuel Oluwadare Balogun Daniel Ken Inaoka Tomoo Shiba Yasutoshi Kido Chiaki Tsuge Takeshi Nara Takashi Aoki Teruki Honma Akiko Tanaka Masayuki Inoue Shigeru Matsuoka Paul A. M. Michels Kiyoshi Kita Shigeharu Harada 《Molecular microbiology》2014,94(6):1315-1329
The glycerol kinase (GK) of African human trypanosomes is compartmentalized in their glycosomes. Unlike the host GK, which under physiological conditions catalyzes only the forward reaction (ATP‐dependent glycerol phosphorylation), trypanosome GK can additionally catalyze the reverse reaction. In fact, owing to this unique reverse catalysis, GK is potentially essential for the parasites survival in the human host, hence a promising drug target. The mechanism of its reverse catalysis was unknown; therefore, it was not clear if this ability was purely due to its localization in the organelles or whether structure‐based catalytic differences also contribute. To investigate this lack of information, the X‐ray crystal structure of this protein was determined up to 1.90 Å resolution, in its unligated form and in complex with three natural ligands. These data, in conjunction with results from structure‐guided mutagenesis suggests that the trypanosome GK is possibly a transiently autophosphorylating threonine kinase, with the catalytic site formed by non‐conserved residues. Our results provide a series of structural peculiarities of this enzyme, and gives unexpected insight into the reverse catalysis mechanism. Together, they provide an encouraging molecular framework for the development of trypanosome GK‐specific inhibitors, which may lead to the design of new and safer trypanocidal drug(s). 相似文献
990.
Nobuo Okahashi Tomoko Sumitomo Masanobu Nakata Atsuo Sakurai Hirotaka Kuwata Shigetada Kawabata 《PloS one》2014,9(1)
Members of the mitis group of streptococci are normal inhabitants of the commensal flora of the oral cavity and upper respiratory tract of humans. Some mitis group species, such as Streptococcus oralis and Streptococcus sanguinis, are primary colonizers of the human oral cavity. Recently, we found that hydrogen peroxide (H2O2) produced by S. oralis is cytotoxic to human macrophages, suggesting that streptococcus-derived H2O2 may act as a cytotoxin. Since epithelial cells provide a physical barrier against pathogenic microbes, we investigated their susceptibility to infection by H2O2-producing streptococci in this study. Infection by S. oralis and S. sanguinis was found to stimulate cell death of Detroit 562, Calu-3 and HeLa epithelial cell lines at a multiplicity of infection greater than 100. Catalase, an enzyme that catalyzes the decomposition of H2O2, inhibited S. oralis cytotoxicity, and H2O2 alone was capable of eliciting epithelial cell death. Moreover, S. oralis mutants lacking the spxB gene encoding pyruvate oxidase, which are deficient in H2O2 production, exhibited reduced cytotoxicity toward Detroit 562 epithelial cells. In addition, enzyme-linked immunosorbent assays revealed that both S. oralis and H2O2 induced interleukin-6 production in Detroit 562 epithelial cells. These results suggest that streptococcal H2O2 is cytotoxic to epithelial cells, and promotes bacterial evasion of the host defense systems in the oral cavity and upper respiratory tracts. 相似文献