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81.
Souhei Sugita Misako Namima Toshitaka Nabeshima Koichi Okamoto Hiroshi Furukawa Yasuhiro Watanabe 《Neurochemistry international》1996,28(5-6):545-550
For the purpose of studying a role of immediate early genes in psychotomimetic-induced behavioral excitation, we experimentally enhanced the locomotor activity of mice by acute administration of phencyclidine and examined the expression and localization of the c-Fos-like and c-Jun-like immunoreactivities in brain regions. A single injection of phencyclidine (5.0 mg/kg, i.p.) significantly increased not only the locomotor activity but also the expression of c-Fos-like immunoreactivity in several brain regions, particularly in the parietal cortex, hippocampal dentate gyrus, piriform cortex and hypothalamus. Interestingly, the c-Fos-like immunoreactivity in the parietal cortex continued to increase for 1 week after the phencyclidine injection. These results indicate that phencyclidine, even injected only once, can induce the persistent expression of c-Fos or c-Fos-related protein(s) in the mouse brain, and also suggest the possibility that such a c-Fos expression may underlie the behavioral and/or psychotomimetic effects of phencyclidine. 相似文献
82.
Haruko Ogawa Ako Hijikata Maho Amano Kyoko Kojima Hisako Fukushima Ineo Ishizuka Yoshie Kurihara Isamu Matsumoto 《Glycoconjugate journal》1996,13(4):555-566
The oligosaccharide structures ofCry j I, a major allergenic glycoprotein ofCryptomeria japonica (Japanese cedar, sugi), were analysed by 400 MHz1H-NMR and two-dimensional sugar mapping analyses. The four major fractions comprised a series of biantennary complex type N-linked oligosaccharides that share a fucose/xylose-containing core and glucosamine branches including a novel structure with a nongalactosylated fucosylglucosamine branch.Rabbit polyclonal anti-Cry j I IgG antibodies cross-reacted with three different plant glycoproteins having the same or shorter N-linked oligosaccharides asCry j I. ELISA and ELISA inhibition studies with intact glycoproteins, glycopeptides and peptides indicated that both anti-Cry j I IgGs and anti-Sophora japonica bark lectin II (B-SJA-II) IgGs included oligosaccharide-specific antibodies with different specificities, and that the epitopic structures against anti-Cry j I IgGs include a branch containing 1–6 linked fucose and a core containing fucose/xylose, while those against anti-B-SJA-II IgGs include nonreducing terminal mannose residues. The cross-reactivities of human allergic sera to miraculin andClerodendron Trichotomum lectin (CTA) were low, and inhibition studies suggested that the oligosaccharides onCry j I contribute little or only conformationally to the reactivity of specific IgE antibodies.Abbreviations
Cry j I
a major allergenic glycoprotein ofCryptomeria japonica
- B-SJA-II
Sophora japonica bark lectin II
- CTA
Clerodendron trichotomum lectin
- TFMS
trifluoromethanesulfonic acid
- HRP
horseradish peroxidase 相似文献
83.
84.
Gerben J. Van Eldik Miriam Wingens René K. Ruiter Marinus M. A. Van Herpen Jan A. M. Schrauwen George J. Wullems 《Plant molecular biology》1996,30(1):171-176
A gene, sts14, coding for a highly expressed mRNA in pistils of Solanum tuberosum, was isolated. Northern blot and in situ analyses demonstrated that the gene was expressed throughout pistil development in both the stylar cortex and the stigma. The deduced STS14 protein displays similarity to the pathogenesis-related PR-1 proteins. A possible function for protection or guidance of the pollen tubes through the pistil is discussed. 相似文献
85.
Daisuke Yamauchi Yoko Terasaki Takashi Okamoto Takao Minamikawa 《Plant molecular biology》1996,30(2):321-329
Cysteine endopeptidases, SH-EP from Vigna mungo and EP-C1 from Phaseolus vulgaris, act to degrade seed storage protein during seed germination. Using transgenic tobacco plants, expression of SH-EP and promoter activity of the EP-C1 gene were analyzed in transgenic tobacco plants. The promoters of the two genes in tobacco seeds showed germination-specific activation, although post-translational processing of SH-EP and regulatory regions of promoter of the gene for EP-C1 were found to differ between leguminous seeds and transgenic tobacco seeds. 相似文献
86.
Riki van den Boogaard Miriam de Boer Erik J. Veneklaas Hans Lambers 《Physiologia plantarum》1996,98(3):493-504
We have investigated the water use efficiency of whole plants and selected leaves and allocation patterns of three wheat cultivars (Mexipak, Nesser and Katya) to explore how variation in these traits can contribute to the ability to grow in dry environments. The cultivars exhibited considerable differences in biomass allocation and water use efficiency. Cultivars with higher growth rates of roots and higher proportions of biomass in roots (Nesser and Katya) also had higher leaf growth rates, higher proportions of their biomass as leaves and higher leaf area ratios. These same cultivars had lower rates of transpiration per unit leaf area or unit root weight and higher biomass production per unit water use. They also had higher ratios of photosynthesis to transpiration, and lower ratios of intercellular to external CO2 partial pressure. The latter resulted from large differences in stomatal conductance associated with relatively small differences in rates of photosynthesis. There was little variation between cultivars in response to drought, and differences in allocation pattern and plant water use efficiency between cultivars as found under well-watered conditions persisted under dry conditions. At the end of the non-watered treatment, relative growth rates and transpiration rates decreased to similar values for all cultivars. High ratios of photosynthesis to transpiration, and accordingly high biomass production per unit of transpiration, is regarded as a favourable trait for dry environments, since more efficient use of water postpones the decrease in plant water status. 相似文献
87.
In the evergreen Fagaceae forests of Japan, an ectomycorrhizal fungusTricholoma bakamatsutake forms shiros or developing mycelial blocks. To determine the physiological characteristics of the mycelial blocks, organic acids of the soil and major nutrient elements of the soil and roots were compared at three types of sites: presently colonized mycelial blocks, previously colonized sites behind the blocks, and uncolonized sites in front of the blocks. The upper part of the mycelial blocks showed the following features compared with the uncolonized site: lower pH (5.1), higher concentrations of oxalic and gluconic acids, lower content of total nitrogen, a similar amount of total carbon, reduced total and available phosphorus, higher content of total calcium and lower content of exchangeable calcium. These findings suggested that the activity of the fungus led to soil acidification by the organic acids, an increase in C/N ratio, depletion of phosphorus and accumulation of calcium. 相似文献
88.
Cloning of the macrolide antibiotic biosynthesis gene acyA, which encodes 3-O-acyltransferase, from Streptomyces thermotolerans and its use for direct fermentative production of a hybrid macrolide antibiotic. 总被引:2,自引:0,他引:2
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A Arisawa N Kawamura K Takeda H Tsunekawa K Okamura R Okamoto 《Applied microbiology》1994,60(7):2657-2660
A gene encoding the macrolide modification enzyme 3-O-acyltransferase (acyA) was cloned by chromosome walking onto the carbomycin biosynthetic region in Streptomyces thermotolerans TH475, with the 3' region of the gene encoding the macrolide modification enzyme 4"-O-acyltransferase (acyB1) as a probe. A shortened fragment (1.8 kb) containing acyA was subcloned with pIJ350. A high-level tylosin producer, Streptomyces fradiae MBBF, transformed with the plasmid could produce a hybrid macrolide, 3-O-acetyltylosin, most efficiently. 相似文献
89.
Zhao Ying Hiromasa Tojo Takanori Komatsubara Manabu Nakagawa Masami Inada Sumio Kawata Yuji Matsuzawa Mitsuhiro Okamoto 《生物化学与生物物理学报:疾病的分子基础》1994,1226(2):201-205
Enzyme activity, protein contents, and mRNA contents of group II phospholipase A2 (PLA2) in hepatocellular carcinoma (HCC) surgically obtained from 8 patients were compared with those in either its neighboring liver tissues or control liver tissues. The PLA2 specific activity towards the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was significantly greater in the tumor tissues (6.62 ± 1.46 nmol/min/mg) than those in the surrounding liver tissues (1.33 ± 0.22 nmol/min/mg) and controls (0.43 ± 0.04 nmol/min/mg). The results of immunoblot analysis using a specific anti-human group II PLA2 antibody and of Northern blot analysis using a human group II PLA2 cDNA as a probe demonstrated that group II PLA2 was responsible for the increased enzyme activity. The contents of immunoreactive group II PLA2 in the tumor tissues (8.81 ± 1.24 ng/mg) were significantly higher than those in the surrounding liver tissues (1.77 ± 0.27 ng/mg); those in the control tissues were below the analytical range of the method used. The group II PLA2 mRNA was also significantly increased in the tumor tissues, compared with that in the surrounding liver tissues, whereas it was not detectable in th controls. This indicates that group II PLA2 in HCC is induced at the pretranslational level. 相似文献
90.
Yoshiko Myoken Yoshinari Myoken Tetsuji Okamoto Mikio Kan J. Denry Sato Kazuaki Takada 《In vitro cellular & developmental biology. Animal》1994,30(11):790-795
Summary A squamous cell carcinoma cell line Nakata proliferated in serum-free culture and was not responsive to exogenous fibroblast
growth factor-1 (FGF-1). Immunostaining revealed that Nakata cells expressed FGF-1 in their cytoplasms and nuclei. Two molecular
mass species of FGF-1 (16 and 18 kDa) were identified in cell extracts by Western blot. These cells also expressed high-affinity
FGF-1 binding sites (Kd=360 pM, 28 000 sites/cell). The results of cross-linking with [125I]FGF-1 demonstrated the presence of two bands with molecular masses of 160 and 140 kDa. The addition of FGF-1 specific antisense
oligonucleotides at 25 μM to Nakata cells resulted in an 82% inhibition in cell growth and suppressed FGF-1 expression. This effect was dose-dependent
and specific, because sense oligonucleotides were ineffective in inhibiting cell growth. In addition, Nakata cell growth was
suppressed by an anti-FGF-1 neutralizing antibody, which resulted in a 52% inhibition at 8 μg/ml. These results demonstrate
that Nakata cells produce FGF-1, and indicate that this growth factor acts in an autocrine manner by interacting with FGF-1
binding sites on Nakata cells. 相似文献