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61.
Yoshimi M Sekiguchi T Hara N Nishimoto T 《Biochemical and biophysical research communications》2000,276(3):965-969
The tsBN7 cell line is one of the temperature-sensitive mutants for cell proliferation derived from hamster BHK21 cell line. It has a mutation in the DAD1 gene and enters apoptosis at the restrictive temperature of 39 degrees C. The defect of Dad1p causes a loss of N-linked glycosylation; therefore, it was thought that an inhibition of N-linked glycosylation induced apoptosis.However, tunicamycin, a potent inhibitor of N-linked glycosylation, had not caused apoptosis in wild-type BHK21 cells. In order to clarify this discrepancy, wild-type BHK21 cells treated with tunicamycin and tsBN7 cells incubated at 39.5 degrees C were examined by the annexin V staining and TUNEL methods. Both methods showed that tunicamycin induces apoptosis in wild-type BHK21 cells, similar to the defect of Dad1p. Thus, we concluded that loss of N-linked glycosylation causes apoptosis. 相似文献
62.
Phenotypic Characterization of Polysaccharidases Produced by Four Prevotella Type Strains 总被引:3,自引:0,他引:3
Matsui H Ogata K Tajima K Nakamura M Nagamine T Aminov RI Benno Y 《Current microbiology》2000,41(1):45-49
Four ruminal Prevotella type strains, P. ruminicola JCM8958T, P. bryantii B14T, P. albensis M384T, and P. brevis ATCC19188T, were characterized for polysaccharide-degrading activities with the reducing sugar release assay and zymogram analyses.
Carboxymethylcellulase, xylanase, and polygalacturonate (PG)-degrading enzyme activities were determined in cultures grown
on oat spelt xylan, xylose, arabinose, cellobiose, and glucose as sole growth substrates. P. ruminicola and P. albensis showed carboxymethylcellulase induction patterns. When xylan was supplied as a sole growth substrate, xylanase activities
produced by P. bryantii and P. albensis were at least 18- and 11-fold higher, respectively, than during growth on other carbohydrates, suggesting that the regulation
of the xylanases was highly specific to xylan. All strains constitutively produced PG-degrading enzymes. The corresponding
activity of P. bryantii was more than 40-fold higher than in other strains. Zymogram analyses routinely detected the presence of high-molecular-weight
(100–170 kDa) polysaccharide-degrading enzymes in ruminal Prevotella. Characteristics of the polysaccharide-degrading activities showed diversity of ruminal Prevotella species.
Received: 29 November 1999 / Accepted: 1 February 2000 相似文献
63.
Cai Y Benno Y Takeda A Yoshida T Itaya T Nakase T 《The Journal of General and Applied Microbiology》1998,44(2):153-159
Thirty-six isolates of Leuconostoc spp. were isolated from yellow spots that occurred on the surface of vacuum-packaged ham. All isolates were Gram-positive, catalase-negative cocci that produced gas from glucose and formed more than 90% of their lactate as D(-) isomer. These isolates could grow at 4 degrees C but not above 30 degrees C and most strains produced yellow spots on the ham. The isolates were divided into three groups by sugar fermentation patterns. Representative strains from three groups showed intergroup DNA homology values of above 88.8%, showing that these groups were composed of a single species. This organism was positioned at a separate branch in the genus Leuconostoc on the phylogenetic tree based on 16S rRNA sequences, which was assigned to Leuconostoc gelidum on the basis of DNA-DNA relatedness. 相似文献
64.
Rho and Rab Small G Proteins Coordinately Reorganize Stress Fibers and Focal Adhesions in MDCK Cells 总被引:6,自引:1,他引:5
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Hiroshi Imamura Kenji Takaishi Katsutoshi Nakano Atsuko Kodama Hideto Oishi Hitoshi Shiozaki Morito Monden Takuya Sasaki Yoshimi Takai 《Molecular biology of the cell》1998,9(9):2561-2575
The Rho subfamily of the Rho small G protein family (Rho) regulates formation of stress fibers and focal adhesions in many types of cultured cells. In moving cells, dynamic and coordinate disassembly and reassembly of stress fibers and focal adhesions are observed, but the precise mechanisms in the regulation of these processes are poorly understood. We previously showed that 12-O-tetradecanoylphorbol-13-acetate (TPA) first induced disassembly of stress fibers and focal adhesions followed by their reassembly in MDCK cells. The reassembled stress fibers showed radial-like morphology that was apparently different from the original. We analyzed here the mechanisms of these TPA-induced processes. Rho inactivation and activation were necessary for the TPA-induced disassembly and reassembly, respectively, of stress fibers and focal adhesions. Both inactivation and activation of the Rac subfamily of the Rho family (Rac) inhibited the TPA-induced reassembly of stress fibers and focal adhesions but not their TPA-induced disassembly. Moreover, microinjection or transient expression of Rab GDI, a regulator of all the Rab small G protein family members, inhibited the TPA-induced reassembly of stress fibers and focal adhesions but not their TPA-induced disassembly, indicating that, furthermore, activation of some Rab family members is necessary for their TPA-induced reassembly. Of the Rab family members, at least Rab5 activation was necessary for the TPA-induced reassembly of stress fibers and focal adhesions. The TPA-induced, small G protein-mediated reorganization of stress fibers and focal adhesions was closely related to the TPA-induced cell motility. These results indicate that the Rho and Rab family members coordinately regulate the TPA-induced reorganization of stress fibers and focal adhesions that may cause cell motility. 相似文献
65.
Takeshi Nishijima Shigeko Yashiro Katsuji Teruya Yoshimi Kikuchi Naomichi Katai Shinichi Oka Hiroyuki Gatanaga 《PloS one》2015,10(9)
Objective
To investigate whether routine eye screening by an ophthalmologist in patients with HIV-1 infection is clinically useful.Methods
A single-center, retrospective study in Tokyo, Japan. HIV-1-infected patients aged over 17 years who visited our clinic for the first time between January 2004 and December 2013 and underwent full ophthalmologic examination were enrolled. At our clinic, ophthalmologic examination, including dilated retinal examination by indirect ophthalmoscopy was routinely conducted by ophthalmologists on the first visit. The prevalence of ophthalmologic diseases and associated factors including the existence of ocular symptoms were analyzed.Results
Of the 1,515 study patients, cytomegalovirus retinitis (CMV-R) was diagnosed in 24 (2%) patients, HIV retinopathy (HIV-R) in 127 (8%), cataract in 31 (2%), ocular syphilis in 4 (0.3%), and uveitis with unknown cause in 8 (0.5%). Other ocular diseases were diagnosed in 14 patients. The CD4 count was <200 /μL in all CMV-R cases and 87% of HIV-R. The prevalence of any ocular diseases, CMV-R, and HIV-R in patients with CD4 <200 /μL were 22%, 3%, and 15%, respectively, whereas for those with CD4 ≥200 /μL were 5%, 0%, and 2%, respectively. No ocular symptoms were reported by 71% of CMV-R cases and 82% of patients with any ocular diseases.Conclusions
Routine ophthalmologic screening is recommended for HIV-1-infected patients with CD4 <200 /μL in resource-rich settings based on the high prevalence of ocular diseases within this CD4 count category and because most patients with ocular diseases, including those with CMV-R, were free of ocular symptoms. 相似文献66.
67.
Tatsuya Yoshimi Fumiko Hashimoto Shigeru Takahashi Yuji Takahashi 《In vitro cellular & developmental biology. Animal》2010,46(8):664-672
The role of HOM/C homeobox genes on rat embryonic lung branching morphogenesis was investigated using the lung bud explant
culture system in an air/liquid interface. Knock down of homeobox b3 and b4 expression by antisense oligonucleotide treatment
repressed airway branch formation, while antisense oligonucleotide against homeobox a3 showed no effect. Addition of antisense
Hoxb3 oligonucleotide resulted in upregulation of collagen type III mRNA and fibroblast growth factor 10 mRNA, while that
of the T-box regulatory factor-4 was decreased. Consequently, expression of Clara cell-specific secretory protein was decreased.
These results suggest a critical role for homeobox b3 and b4 genes in lung airway branching morphogenesis. 相似文献
68.
Yoshimi Tokuzawa Ken Yagi Yzumi Yamashita Yutaka Nakachi Itoshi Nikaido Hidemasa Bono Yuichi Ninomiya Yukiko Kanesaki-Yatsuka Masumi Akita Hiromi Motegi Shigeharu Wakana Tetsuo Noda Fred Sablitzky Shigeki Arai Riki Kurokawa Toru Fukuda Takenobu Katagiri Christian Sch?nbach Tatsuo Suda Yosuke Mizuno Yasushi Okazaki 《PLoS genetics》2010,6(7)
69.
Maekawa M Iwayama Y Watanabe A Nozaki Y Ohnishi T Ohba H Toyoshima M Hamazaki K Osumi N Aruga J Yoshikawa T 《Biochemical and biophysical research communications》2010,402(2):431-437
The eyes are riched in long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic acid [ARA; 20:4 (n−6)] and docosahexaenoic acid [DHA; 22:6 (n−3)]. Despite their abundance in the eyes, ARA and DHA cannot be sufficiently synthesized de novo in mammals. During gestation, eye development is exceptionally rapid, and substantial amounts of LC-PUFAs are needed to ensure proper eye development. Here, we studied the influences of dietary LC-PUFAs in dams (C57BL/6 and C3H/He) on the eye morphogenesis and organogenesis of their pups. Intriguingly, fetuses and newborn mice from C57BL/6 dams fed an LC-PUFA (particularly ARA)-enriched diet displayed a much higher incidence of eye abnormalities such as microphthalmia (small eye) and corneal opacity than those from dams fed an LC-PUFA-poor diet. The effects of LC-PUFAs on eye anomalies were evident only in the female pups of C57BL/6 inbred mice, not in those of C3H/He mice or male C57BL/6 mice. These results demonstrate a gene-by-environment (GxE) interaction in eye development in mice. Furthermore, our molecular analysis suggested the potential roles of Pitx3 and Pax6 in the above interaction involving ARA. 相似文献
70.
Unlike known Chlamydomonas species, Chlamydomonas sp. strain W80, which was isolated from seawater, shows tolerance to salt and cadmium. In this study, we purified and characterized cysteine protease from Chlamydomonas sp. strain W80 cells and also investigated their response to oxidative stress. The protease was purified 2760-fold with a yield of 2.6% by five steps of successive chromatography. This protease had a pH optimum of 8.0 and was specific only for tert -butoxycarbonyl (Boc)-Leu-Arg-Arg-4-methylcoumaryl-7-amide (MCA) (Boc-LRR-MCA) and Boc-Val-Leu-Lys-MCA as substrates among eight fluorogenic peptides tested. The K m value was estimated to be 44.4 μ M for Boc-LRR-MCA. The molecular weight of the protease was determined to be approximately 102 kDa by Superdex 200 gel filtration and 60 kDa by SDS–PAGE, suggesting that this enzyme is a dimer. This enzyme was inhibited by the cysteine protease inhibitors leupeptin and N-ethylmaleimide but neither inhibited by phenylmethylsulfonyl fluoride or ethylenediaminetetraacetic acid nor activated by metal cations. These findings indicate that this enzyme is likely a cysteine protease. When strain W80 was grown under oxidative stress in the presence of methyl viologen and cadmium chloride, cysteine protease activity was about 30–90% higher than normal, whereas no changes were observed in carbon enrichment or senescence. It is likely that this protease is upregulated in response to oxidative stress and plays a role in the maintenance of cell metabolism under oxidative stress conditions. 相似文献