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1.
O Chisaka K Araki T Ochiya T Tsurimoto W Hiranyawasitte-Attatippaholkun N Yanaihara K Matsubara 《Gene》1987,60(2-3):183-189
A fused gene containing 94% of the hepatitis B virus (HBV) open reading frame X was expressed in Escherichia coli, and its 17-kDa product was purified by ion-exchange chromatography. Antibody elicited against the X-gene product reacted with materials proximal to the nuclear membrane of a human hepatoblastoma cell line producing HBV particles. No such reaction was observed with the same cell line that did not produce HBV particles. 相似文献
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3.
Toshiki Hiroyoshi 《Genetics》1961,46(10):1373-1380
4.
Chaomurilege Zu Yanhui Miyagi Atsuko Hashida Shin-Nosuke Ishikawa Toshiki Yamaguchi Masatoshi Kawai-Yamada Maki 《Journal of plant research》2023,136(1):97-106
Journal of Plant Research - Chloroplast-localized NAD kinase (NADK2) is responsible for the production of NADP+, which is an electron acceptor in the linear electron flow of photosynthesis. The... 相似文献
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6.
Toshiaki Koizumi Toshiki Yokota Mikiko Fukuchi Hideki Tatsumoto Yasuhiro Yamane 《Cell biology and toxicology》1991,7(4):357-369
In order to clarify the protective mechanism of sodium molybdate against the acute toxicity of cadmium chloride in rat, the effect of in vivo sodium molybdate pretreatment on the cytotoxic action of cadmium in isolated hepatocytes was studied. The cytosolic pH of hepatocytes isolated from untreated rats immediately decreased with incubation in either neutral Hank's balanced salt solution (HBS), pH 7.4, containing 5 µM cadmium chloride minimum or acidic HBS (pH 7.1, 6.8, 6.5, and 6.2). The presence of 5 µM cadmium in HBS adjusted to pH 7.1 aggravated cytosalic acidification induced by the acidic medium alone. Cell viability of hepatocytes incubated in HBS at pH 6.2 was significantly reduced as compared to that of control cells in HBS at pH 7.4, but the presence of cadmium in the acidic HBS had no aggravating action against such a toxic action of the acidic medium although cellular uptake of the metal in the medium increased, as compared to that in HBS at pH 7.4. Molybdenum pretreatment alleviated cytoplasmic acidification induced by the treatment with HBS at pH 7.4 or 7.1 containing cadmium or by extracellular acid load wothout cadmium. This pretreatment also prevented the loss of cell viability induced by the treatment with HBS at pH 6.2 but could not attenuate that when cadmium was present in the medium.These facts suggest that molybdenum pretreatment alleviated the acute toxicity of cadmium in rat by preventing cytoplasmic acidification caused by the harmful metal. 相似文献
7.
Complete genomic sequence of nitrogen-fixing symbiotic bacterium Bradyrhizobium japonicum USDA110. 总被引:7,自引:0,他引:7
Takakazu Kaneko Yasukazu Nakamura Shusei Sato Kiwamu Minamisawa Toshiki Uchiumi Shigemi Sasamoto Akiko Watanabe Kumi Idesawa Mayumi Iriguchi Kumiko Kawashima Mitsuyo Kohara Midori Matsumoto Sayaka Shimpo Hisae Tsuruoka Tsuyuko Wada Manabu Yamada Satoshi Tabata 《DNA research》2002,9(6):189-197
The complete nucleotide sequence of the genome of a symbiotic bacterium Bradyrhizobium japonicum USDA110 was determined. The genome of B. japonicum was a single circular chromosome 9,105,828 bp in length with an average GC content of 64.1%. No plasmid was detected. The chromosome comprises 8317 potential protein-coding genes, one set of rRNA genes and 50 tRNA genes. Fifty-two percent of the potential protein genes showed sequence similarity to genes of known function and 30% to hypothetical genes. The remaining 18% had no apparent similarity to reported genes. Thirty-four percent of the B. japonicum genes showed significant sequence similarity to those of both Mesorhizobium loti and Sinorhizobium meliloti, while 23% were unique to this species. A presumptive symbiosis island 681 kb in length, which includes a 410-kb symbiotic region previously reported by G?ttfert et al., was identified. Six hundred fifty-five putative protein-coding genes were assigned in this region, and the functions of 301 genes, including those related to symbiotic nitrogen fixation and DNA transmission, were deduced. A total of 167 genes for transposases/104 copies of insertion sequences were identified in the genome. It was remarkable that 100 out of 167 transposase genes are located in the presumptive symbiotic island. DNA segments of 4 to 97 kb inserted into tRNA genes were found at 14 locations in the genome, which generates partial duplication of the target tRNA genes. These observations suggest plasticity of the B. japonicum genome, which is probably due to complex genome rearrangements such as horizontal transfer and insertion of various DNA elements, and to homologous recombination. 相似文献
8.
Localization of anchor loci representing five hundred annotated rice genes to wheat chromosomes using PLUG markers 总被引:1,自引:0,他引:1
Goro Ishikawa Toshiki Nakamura Taizo Ashida Mika Saito Shuhei Nasuda Takashi R. Endo Jianzhong Wu Takashi Matsumoto 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(3):499-514
PCR-based Landmark Unique Gene (PLUG) markers are EST-PCR markers developed based on the orthologous gene conservation between
rice and wheat, and on the intron polymorphisms among the three orthologous genes derived from the A, B and D genomes of wheat.
We designed a total of 960 primer sets from wheat ESTs that showed high similarity with 951 single-copy rice genes. When genomic
DNA of Chinese Spring wheat was used as a template, 872 primer sets amplified one to five distinct products. Out of these
872 PLUG markers, 531 were assigned to one or more chromosomes by nullisomic-tetrasomic analysis. For each wheat chromosome,
the number of loci detected ranged from 32 for chromosome 6A to 73 for chromosome 7D, with an average of 48 loci per chromosome.
Several novel synteny perturbations were identified using deletion bin-mapping of markers. Furthermore, we demonstrated that
PLUG markers can be used as probes to simultaneously identify BAC clones that contain homoeologous regions from all three
genomes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
9.
Plasmid vectors designed for high-efficiency expression controlled by the portable recA promoter-operator of Escherichia coli 总被引:7,自引:0,他引:7
A novel expression vector using the 236-bp promoter-operator fragment of the recA gene (recApo) of Escherichia coli has been constructed. This DNA fragment contains complete signals for the initiation of RNA synthesis, as well as for regulation by the lexA product, but lacks the coding sequence for the RecA protein. The strength of the recA promoter was examined by assaying beta-galactosidase activity expressed from a cro-lacZ fused gene placed downstream of the promoter. Under noninducing conditions, the promoter was regulated by the LexA protein, and the fused gene was expressed only weakly. Upon induction by nalidixic acid in a recA+ strain, high expression was observed for an extended period. After 5 h under inducing conditions, as much as 11% of the total cellular protein was cro-lacZ product. The expression level was higher than that from promoters of lac, trp, and lambda early genes. 相似文献
10.
Kato K Yazawa T Taki K Mori K Wang S Nishioka T Hamaguchi T Itoh T Takenawa T Kataoka C Matsuura Y Amano M Murohara T Kaibuchi K 《Molecular biology of the cell》2012,23(13):2593-2604
Cell migration is essential for various physiological and pathological processes. Polarization in motile cells requires the coordination of several key signaling molecules, including RhoA small GTPases and phosphoinositides. Although RhoA participates in a front-rear polarization in migrating cells, little is known about the functional interaction between RhoA and lipid turnover. We find here that src-homology 2-containing inositol-5-phosphatase 2 (SHIP2) interacts with RhoA in a GTP-dependent manner. The association between SHIP2 and RhoA is observed in spreading and migrating U251 glioma cells. The depletion of SHIP2 attenuates cell polarization and migration, which is rescued by wild-type SHIP2 but not by a mutant defective in RhoA binding. In addition, the depletion of SHIP2 impairs the proper localization of phosphatidylinositol 3,4,5-trisphosphate, which is not restored by a mutant defective in RhoA binding. These results suggest that RhoA associates with SHIP2 to regulate cell polarization and migration. 相似文献