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排序方式: 共有587条查询结果,搜索用时 31 毫秒
101.
Mohammed Nuruzzaman Tatsuo Kanno Rika Amada Yoshiki Habu Ichiro Kasajima Toshiki Ishikawa Maki Kawai-Yamada Hirofumi Uchimiya 《PloS one》2014,9(9)
The genomic nucleotide sequences of japonica rice (Sasanishiki and Nipponbare) contained about 2.7-kb unique region at the point of 0.4-kb upstream of the OsPsbS1 gene. In this study, we found that japonica rice with a few exceptions possessing such DNA sequences [denoted to OsMULE-japonica specific sequence (JSS)] is distinct by the presence of Mutator-like-element (MULE). Such sequence was absent in most of indica cultivars and Oryza glaberrima. In OsMULE-JSS1, we noted the presence of possible target site duplication (TSD; CTTTTCCAG) and about 80-bp terminal inverted repeat (TIR) near TSD. We also found the enhancement ofOsPsbS1 mRNA accumulation by intensified light, which was not associated with the DNA methylation status in OsMULE/JSS. In addition, O. rufipogon, possible ancestor of modern rice cultivars was found to compose PsbS gene of either japonica (minor) or indica (major) type. Transient gene expression assay showed that the japonica type promoter elevated a reporter gene activity than indica type. 相似文献
102.
Toshiyuki Oda Haruaki Yanagisawa Toshiki Yagi Masahide Kikkawa 《The Journal of cell biology》2014,204(5):807-819
Cilia/flagella are conserved organelles that generate fluid flow in eukaryotes. The bending motion of flagella requires concerted activity of dynein motors. Although it has been reported that the central pair apparatus (CP) and radial spokes (RSs) are important for flagellar motility, the molecular mechanism underlying CP- and RS-mediated dynein regulation has not been identified. In this paper, we identified nonspecific intermolecular collision between CP and RS as one of the regulatory mechanisms for flagellar motility. By combining cryoelectron tomography and motility analyses of Chlamydomonas
reinhardtii flagella, we show that binding of streptavidin to RS heads paralyzed flagella. Moreover, the motility defect in a CP projection mutant could be rescued by the addition of exogenous protein tags on RS heads. Genetic experiments demonstrated that outer dynein arms are the major downstream effectors of CP- and RS-mediated regulation of flagellar motility. These results suggest that mechanosignaling between CP and RS regulates dynein activity in eukaryotic flagella. 相似文献
103.
Fumio Kamiya Masayuki Ueda Chikako NitoNobuo Kamiya Toshiki InabaSatoshi Suda Tomonari SaitoKanako Muraga Yasuo Katayama 《Life sciences》2014
Aims
Transplantation of bone marrow mononuclear cells (BMMCs) exerts neuroprotection against cerebral ischemia. We examined the therapeutic timepoint of allogeneic BMMC transplantation in a rat model of focal cerebral ischemia, and determined the effects of repeated transplantation outside the therapeutic window.Main methods
Male Sprague–Dawley rats were subjected to 90 minute focal cerebral ischemia, followed by intravenous administration of 1 × 107 allogeneic BMMCs or vehicle at 0, 3 or 6 h after reperfusion or 2 × 107 BMMCs 6 h after reperfusion. Other rats administered 1 × 107 BMMCs at 6 h after reperfusion received additional BMMC transplantation or vehicle 9 h after reperfusion. Infarct volumes, neurological deficit scores and immunohistochemistry were evaluated 24 or 72 h after reperfusion.Key findings
Infarct volumes at 24 h were significantly decreased in transplantation rats at 0 and 3 h, but not at 6 h, after reperfusion, compared to vehicle-treatment. Even high dose BMMC transplantation at 6 h after reperfusion was ineffective. Repeated BMMC transplantation at 6 and 9 h after reperfusion reduced infarct volumes and significantly improved neurological deficit scores at 24 and 72 h. Immunohistochemistry showed repeated BMMC transplantation reduced ionized calcium-binding adapter molecule 1, 4-hydroxy-2-nonenal and 8-hydroxydeoxyguanosine expression at 24 and 72 h after reperfusion.Significance
Intravenous allogeneic BMMCs were neuroprotective following transient focal cerebral ischemia, and the therapeutic time window of BMMC transplantation was > 3 h and < 6 h after reperfusion in this model. Repeated transplantation at 6 and 9 h after reperfusion suppressed inflammation and oxidative stress in ischemic brains, resulting in improved neuroprotection. 相似文献104.
Masayuki Ushio Hisato Fukuda Toshiki Inoue Kobayashi Makoto Osamu Kishida Keiichi Sato Koichi Murata Masato Nikaido Tetsuya Sado Yukuto Sato Masamichi Takeshita Wataru Iwasaki Hiroki Yamanaka Michio Kondoh Masaki Miya 《Molecular ecology resources》2017,17(6):e63-e75
Terrestrial animals must have frequent contact with water to survive, implying that environmental DNA (eDNA) originating from those animals should be detectable from places containing water in terrestrial ecosystems. Aiming to detect the presence of terrestrial mammals using forest water samples, we applied a set of universal PCR primers (MiMammal, a modified version of fish universal primers) for metabarcoding mammalian eDNA. The versatility of MiMammal primers was tested in silico and by amplifying DNAs extracted from tissues. The results suggested that MiMammal primers are capable of amplifying and distinguishing a diverse group of mammalian species. In addition, analyses of water samples from zoo cages of mammals with known species composition suggested that MiMammal primers could successfully detect mammalian species from water samples in the field. Then, we performed an experiment to detect mammals from natural ecosystems by collecting five 500‐ml water samples from ponds in two cool‐temperate forests in Hokkaido, northern Japan. MiMammal amplicon libraries were constructed using eDNA extracted from water samples, and sequences generated by Illumina MiSeq were subjected to data processing and taxonomic assignment. We thereby detected multiple species of mammals common to the sampling areas, including deer (Cervus nippon), mouse (Mus musculus), vole (Myodes rufocanus), raccoon (Procyon lotor), rat (Rattus norvegicus) and shrew (Sorex unguiculatus). Many previous applications of the eDNA metabarcoding approach have been limited to aquatic/semiaquatic systems, but the results presented here show that the approach is also promising even for forest mammal biodiversity surveys. 相似文献
105.
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
106.
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
107.
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
108.
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
109.
Takashi Umeda Kazuo Saito Masashi Matsuzaka Shigeyuki Nakaji Manabu Totsuka Toshiki Okumura Toshiaki Tsukamoto Makoto Yaegaki Umi Kudoh Ippei Takahashi 《Luminescence》2008,23(3):115-120
In order to examine in detail the influence on the neutrophil immune function in sumo wrestlers of performing traditional and original training we examined changes in the neutrophil immune function in 17 male amateur university sumo wrestlers (aged 20.2 ± 1.5 years), before (‘Pre’) and after the training (‘Post’) for 2.5 h under fasting conditions. Assays included blood leukocyte and neutrophil counts, serum concentration of immunoglobulins, complements, myogenic enzymes and neutrophil oxidative burst activity (OBA) and phagocytic activity (PA). Myogenic enzymes, neutrophil counts, the ratio of neutrophil counts:leukocyte counts significantly increased and immunoglobulins and complements decreased in Post compared with Pre. There was a positive correlation between the change of neutrophil counts before and after the training and the change of creatine kinase (r = 0.667, p < 0.01). The Post OBA significantly increased and PA significantly decreased compared with Pre. It was concluded that sumo training causes muscular damage and an increase in the neutrophil count as a response. In this time, although OBA increased, PA decreased after training. Compensation between PA and reactive oxygen species production may exist to maintain the overall integrity of the neutrophil immune function. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
110.
Germline transformation of the silkworm Bombyx mori L. using a piggyBac transposon-derived vector 总被引:21,自引:0,他引:21
Tamura T Thibert C Royer C Kanda T Abraham E Kamba M Komoto N Thomas JL Mauchamp B Chavancy G Shirk P Fraser M Prudhomme JC Couble P Toshiki T Chantal T Corinne R Toshio K Eappen A Mari K Natuo K Jean-Luc T Bernard M Gérard C Paul S Malcolm F Jean-Claude P Pierre C 《Nature biotechnology》2000,18(1):81-84
We have developed a system for stable germline transformation in the silkworm Bombyx mori L. using piggyBac, a transposon discovered in the lepidopteran Trichoplusia ni. The transformation constructs consist of the piggyBac inverted terminal repeats flanking a fusion of the B. mori cytoplasmic actin gene BmA3 promoter and the green fluorescent protein (GFP). A nonautonomous helper plasmid encodes the piggyBac transposase. The reporter gene construct was coinjected into preblastoderm eggs of two strains of B. mori. Approximately 2% of the individuals in the G1 broods expressed GFP. DNA analyses of GFP-positive G1 silkworms revealed that multiple independent insertions occurred frequently. The transgene was stably transferred to the next generation through normal Mendelian inheritance. The presence of the inverted terminal repeats of piggyBac and the characteristic TTAA sequence at the borders of all the analyzed inserts confirmed that transformation resulted from precise transposition events. This efficient method of stable gene transfer in a lepidopteran insect opens the way for promising basic research and biotechnological applications. 相似文献