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21.
To evaluate the spawning success of male Japanese minnows,Pseudorasbora parva, and female mate choice, spawning behaviour was observed under both artificial and experimental conditions. Larger males
had larger territories and greater reproductive success. The body weight of territorial males decreased during the maintenance
of territories, while that of non-territorial males increased significantly. When the weight of non-territorial males exceeded
that of territorial males, the former began to establish new territories on the substrate, suggesting a conditional strategy
by non-territorial males to trade off immediate reproductive success with growth and hence improve future reproductive success.
Females chose males with larger body size, probably based on dominance rank rather than the quality (or size) of territory.
It was concluded that females choose males of higher dominance rank and that males compete for large territories, both of
which play an important part in male reproductive success. 相似文献
22.
Induction of a Nerve Growth Factor-Sensitive Kinase that Phosphorylates the DNA-Binding Domain of the Orphan Nuclear Receptor NGFI-B 总被引:2,自引:0,他引:2
Yoko Hirata Michael Whalin David D. Ginty Jun Xing Michael E. Greenberg †Jeffrey Milbrandt Gordon Guroff 《Journal of neurochemistry》1995,65(4):1780-1788
Abstract: Nerve growth factor (NGF) induces the synthesis and the phosphorylation of the orphan nuclear receptor NGFI-B in PC12 cells. Previous work has shown that phosphorylation, by protein kinase A, of a specific serine in the DNA-binding domain inhibits its binding to the NGFI-B response element. Also, cytoplasmic extracts from PC12 cells phosphorylate this serine, and phosphorylation is greater in extracts from cells treated with NGF. The present work describes the induction, identification, and partial purification of a kinase (termed NGFI-B kinase I) from PC12 cell extracts that catalyzes this phosphorylation. Phosphorylation of the DNA-binding domain with this purified preparation inhibits its binding to the NGFI-B response element. The kinase is rapidly activated by treatment of the cells with NGF, and the activation lasts for at least several hours. It also is activated by fibroblast growth factor and epidermal growth factor (EGF), but the activation by EGF is quite transient. The kinase requires Mg2+ but will use Mn2+ . The molecular mass of the kinase is 95–100 kDa, and it is different from protein kinase A, Fos kinase, or pp90 rsk . Comparison with a partially purified preparation of cyclic AMP response element-binding protein kinase, however, indicates that the two are either very similar or identical. 相似文献
23.
Naruo Nikoh Naoyuki Iwabe Kei-ichi Kuma Mutsuhito Ohno Tsutomu Sugiyama Yoko Watanabe Kinya Yasui Zhang Shi-cui Katsuji Hori Yoshiro Shimura Takashi Miyata 《Journal of molecular evolution》1997,45(1):97-106
Previously we suggested that four proteins including aldolase and triose phosphate isomerase (TPI) evolved with approximately
constant rates over long periods covering the whole animal phyla. The constant rates of aldolase and TPI evolution were reexamined
based on three different models for estimating evolutionary distances. It was shown that the evolutionary rates remain essentially
unchanged in comparisons not only between different classes of vertebrates but also between vertebrates and arthropods and
even between animals and plants, irrespective of the models used. Thus these enzymes might be useful molecular clocks for
inferring divergence times of animal phyla. To know the divergence time of Parazoa and Eumetazoa and that of Cephalochordata
and Vertebrata, the aldolase cDNAs from Ephydatia fluviatilis, a freshwater sponge, and the TPI cDNAs from Ephydatia fluviatilis and Branchiostoma belcheri, an amphioxus, have been cloned and sequenced. Comparisons of the deduced amino acid sequences of aldolase and TPI from the
freshwater sponge with known sequences revealed that the Parazoa–Eumetazoa split occurred about 940 million years ago (Ma)
as determined by the average of two proteins and three models. Similarly, the aldolase and TPI clocks suggest that vertebrates
and amphioxus last shared a common ancestor around 700 Ma and they possibly diverged shortly after the divergence of deuterostomes
and protostomes. 相似文献
24.
Yoshihisa Iwamoto Yusaku Suzuki Akinobu Kurita Yoko Watanabe Tadayori Shimizu Hirohisa Ohgami Yasutake Yanagihara 《Microbiology and immunology》1995,39(11):831-837
A new species, Vibrio trachuri sp. nov., was isolated from the cultured Japanese horse mackerel (Trachurus japonicus). These Vibrio were Gram negative, motile rods and formed yellow colonies on BTB teepol and TCBS plate, turned TSI medium to yellow and was sensitive to 150 μM O/129 (2,4-diamino-6,7-diisopropyl pteridine phosphate) like Listonella anguillarum which has been described as Vibrio anguillarum. However, the results of VP test and decarboxylation of lysine or dihydrolation of arginine suggested that these Vibrio are rather closely related to V. parahaemolyticus. DNA similarity determined by the microplate hybridization technique revealed that these Vibrio are genetically quite distant from Listonella anguillarum or V. parahaemolyticus and rather close to V. harveyi, although there was no Vibrio species which had more than 70% similarity value. From these results we propose to nominate Vibrio trachuri sp. nov. for this new Vibrio species. 相似文献
25.
26.
The 14N nuclear relaxation times T1 and T2 in egg yolk phosphatidylcholine have been observed in single bilayer vesicles dispersed in the media of different viscosities, 1H2O and 2H2O. The lateral diffusion coefficient of lipid molecule D has been calculated according to the method reported earlier: D = 2.2 × 10?8cm2s?1 in 1H2O and 2.1 × 10?8cm2s?1 in 2H2O at 20°C. They are in excellent agreement. This result gives a strong basis of usefulness of 14N NMR method in the evaluation of D without introducing any system perturbation. 相似文献
27.
Yoshiaki Kato Yoko Numajiri 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,562(1-2)
A method has been developed for the rapid determination of sugars, including molecular weight measurements, using high-performance liquid chromatography coupled with negative-ion, atmospheric-pressure chemical-ionization mass spectrometry. The chromatography was carried out on a 250 × 4 mm I.D. column packed with 7 μm NH2-silica. The mobile phase consisted of a high percentage of methanol or acetonitrile with a small amount of chloroform. During the mass spectrometry, a strong base is formed from the polar solvent molecules by corona discharge, followed by ion—molecule reactions in the chemical ionization ion source (e.g. the methoxy anion is formed from methanol). This strong base reacts with the chloroform, generating chloride ions, which in turn react with the neutral sugar molecules as they elute from the chromatograph. The chloride ion and sugar interactions yield chloride-attachment ions, which are further stabilized by successive collisions. In this method, authentic monosaccharides and some oligosaccharides show dominant quasi-molecular ions, [M + Cl]−, with little fragmentation, and it is particularly useful for the molecular weight determination of sugars. 相似文献
28.
Dr. Yoko Kameda 《Cell and tissue research》1982,225(3):693-697
Summary Small follicles composed solely of C cells were occasionally observed in large C cell groups of dog thyroid glands. The lumina of C-cell follicles were filled with, or contained peripheral depositions of PAS-positive amorphous material, which was similar in ultrastructural features to thyroglobulin-containing colloid in typical thyroid follicles. This indicates that C cells, in addition to secreting calcitonin, produce a glycoprotein that can be stored in the lumina of the follicles. 相似文献
29.
Akitane Mori Masayuki Akagi Yasuto Katayama Yoko Watanabe 《Journal of neurochemistry》1980,35(3):603-605
: Guanidino compounds in the cobalt-induced epileptogenic cerebral cortex of cats were fluorometrically analysed by a JASCO G-520 guanidino compounds analyser, and an unknown high peak was observed in the chromatogram that was identical to the peak of authentic α-guanidinoglutaric acid. In another experiment, the substance was extracted from the cobalt focus tissue, converted into dimethylpyrimidyl derivative-butylester, and analysed by a GC/MS technique. The mass spectrum of the substance was identical to the dimethylpyrimidyl derivative of α-guanidinoglutaric acid butylester (M+= 365). 相似文献
30.
Y Yoko 《Acta anatomica》1975,91(3):455-461
Two human embryos which were immediately before and soon after the appearance of the cerebral vesicle were cut into complete serial sections in almost the same direction and studied comparatively. The findings on these two sets of serial sections indicate that the rostral continuations of subthalamus and ventral thalamus along the ventral thalamic sulcus continuing from the sulcus limitans of the midbrain are destined to give rise to the formation of the cerebral vesicle. The rostral continuation of the subthalamus becomes the floor of the interventricular foramen, and that of the ventral thalamus the pallium. The rostral end of the continuation of the subthalamic matrix is not only the site of the beginning of evagination of the cerebral vesicle, but also the site of elevation of the ganglionic hill or striatum. As the evagination of the cerebral vesicle proceeds exceedingly dorsocaudolaterally from the rostral end of the continuation of the ventral thalamus, the elevation of the striatum occurs also in the same direction, getting in touch with the folding of the hemispheric stalk of Kuhlenbeck to enclose the interventricular foramen. Tt is noticed that, at the beginning of evagination, the grade of depression of the nasal pit was always parallel with that of evagniation of the cerebral vesicle. 相似文献