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71.
Induction and activation of the transcription factor NFATc1 (NFAT2) integrate RANKL signaling in terminal differentiation of osteoclasts 总被引:15,自引:0,他引:15
72.
Harrison A Sakato M Tedford HW Benashski SE Patel-King RS King SM 《Cell motility and the cytoskeleton》2002,52(3):131-143
The outer dynein arm from Chlamydomonas flagella contains two redox-active thioredoxin-related light chains associated with the alpha and beta heavy chains; these proteins belong to a distinct subgroup within the thioredoxin family. This observation suggested that some aspect of dynein activity might be modulated through redox poise. To test this, we have examined the effect of sulfhydryl oxidation on the ATPase activity of isolated dynein and axonemes from wildtype and mutant strains lacking various heavy chain combinations. The outer, but not inner, dynein arm ATPase was stimulated significantly following treatment with low concentrations of dithionitrobenzoic acid; this effect was readily reversible by dithiol, and to a lesser extent, monothiol reductants. Mutational and biochemical dissection of the outer arm revealed that ATPase activation in response to DTNB was an exclusive property of the gamma heavy chain, and that enzymatic enhancement was modulated by the presence of other dynein components. Furthermore, we demonstrate that the LC5 thioredoxin-like light chain binds to the N-terminal stem domain of the alpha heavy chain and that the beta heavy chain-associated LC3 protein also interacts with the gamma heavy chain. These data suggest the possibility of a dynein-associated redox cascade and further support the idea that the gamma heavy chain plays a key regulatory role within the outer arm. 相似文献
73.
High levels of RAE-1 isoforms on mouse tumor cell lines assessed by anti-"pan" RAE-1 antibody confer tumor susceptibility to NK cells. 总被引:2,自引:0,他引:2
Hisayo Masuda Yoshiko Saeki Midori Nomura Kyoko Shida Misako Matsumoto Michio Ui Lewis L Lanier Tsukasa Seya 《Biochemical and biophysical research communications》2002,290(1):140-145
Two sublines of the benzpyrene-induced mouse hepatoma cell line, G-1 and G-5, showed low and high metastatic ability, respectively, to the lung. We produced a polyclonal antibody (pAb) against RAE-1alpha. Five isoforms of RAE-1 have been identified to date, and this pAb recognized all isoforms and was named anti-"pan" RAE-1 pAb. The level of RAE-1 was approximately 5-fold higher in G-5 than in G-1, which was almost RAE-1-negative, as determined using anti-pan RAE-1 pAb. Expression levels of other markers including MHC class I (MHC-I) and Qa-1b were very low and indistinguishable in these sublines. NK-mediated cytotoxicity was determined with these sublines; G-5 was highly susceptible to NK-mediated cytolysis, while G-1 was relatively resistant. The NK-mediated G-5 > G-1 killing profile was diminished if the G-5 cells were pretreated with F(ab)(2)(') of anti-pan RAE-1 pAb. G-1, when transfected with Rae-1alpha cDNA, acquired NK-responsiveness similar to that of G-5. These and additional data using mouse cell lines with low MHC-I levels and various RAE-1 levels also demonstrated that RAE-1 level is critically associated with NK-susceptibility in tumor cells. 相似文献
74.
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76.
Hydrogenobacter thermophilus strain TK-6 was observed to grow anaerobically on nitrate as an electron acceptor when molecular hydrogen was used as an energy source. Nitrite was detected as the product of a respiratory reaction. 15NO, 15N2O, and 15N2 were detected with Na15NO3 as an electron acceptor. Western immunoblot analysis showed that cell-free extracts from cells grown on nitrate reacted with antibodies against heme cd1-type nitrite reductase from Pseudomonas aeruginosa. The positive bands, which had molecular masses similar to that of the heme cd1-type nitrite reductase, were also stained by heme staining. These results indicate that nitrite reductase of strain TK-6 is a heme cd1-type enzyme. Activity of ATP:citrate lyase, one of the key enzymes of the reductive TCA cycle, was detected in cell-free extract of cells cultivated on nitrate, which indicates that the cycle operates during anaerobic growth. 相似文献
77.
Shida T Hattori H Ise F Sekiguchi J 《Bioscience, biotechnology, and biochemistry》2000,64(7):1522-1525
N-acetylmuramoyl-L-alanine amidase CwlC of Bacillus subtilis was overproduced in Escherichia coli and purified 21-fold. The amidase hydrolyzed type A cell walls such as B. subtilis. The amidase bound slightly to the Microbacterium lacticum cell wall (type B), but did not entirely hydrolyze it. The presence of calcium or magnesium ion increased the resistance of the amidase to heat denaturation. 相似文献
78.
Miho Iijima Kazuhiro Aiba Yoshimasa Tanaka Hideko Urushihara 《Journal of plant research》1998,111(1):93-96
Two cDNA fragments induced in developing zygotes ofDictyostelium discoideum were isolated by mRNA differential display. the relevant genes were also found to be expressed during asexual development,
suggesting that sexual and asexual development share common molecular mechanisms inD. discoideum. 相似文献
79.
Soybean meal was fermented withAspergillus usamii to improve zinc availability through the degradation of phytic acid. Rats fed a diet containing fermented soybean meal showed
greater femoral zinc than did animals fed a diet containing regular soybean meal. Zinc solubility in the small intestine was
higher in the rats fed fermented soybean meal than in the rats fed regular soybean meal. These results suggested that fermentation
withAspergillus usamii improved zinc availability in dietary soybean meal, which was induced by the increase of zinc solubility in the small intestine.
Adding the same amount of phytate that was contained in the regular soybean mealbased diet did not affect the amount of zinc
present in rats fed a fermented soybean meal-based diet with sodium phytate. Phytase activity was found in fermented soybean
meal, and this activity may degrade added phytate in fermented soybean meal-based diet. 相似文献
80.
Miho Honma Shinji Kudo Noboru Takada Kazuaki Tanaka Tomisato Miura Masaru Hashimoto 《Bioorganic & medicinal chemistry letters》2010,20(2):709-712
Novel fusapyrone analogs, deoxyneofusapyrone and 7-desmethyldeoxyneofusapyrone were isolated from a pathogenic fungus, Verticillium dahliae, which causes Verticillium wilt disease in Helianthus annuus. Spectral analyses revealed that these are 2-pyrone type analogs of deoxyfusapyrone and its 7-desmethyl derivative, respectively. Biological assay disclosed that 10 μg of deoxyneofusapyrone inhibited the growth of MRSA clinical isolate 87-7927. 相似文献