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121.
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123.
The effects of UV-B radiation (290–320 nm) on development of damping-off of spinach (Spinacia oleracea) caused by the fungusFusarium oxysporum were examined in a growth cabinet. The incidence of disease greatly increased when experimental plants were grown in visible
radiation with supplementary UV-B radiation. This increase was suppressed by increasing the irradiation of visible radiation.Fusarium oxysporum was isolated from the roots of all damping-off plants and the roots of some unwilted plants, indicating that spinach infected
with the pathogen did not necessarily suffer from damping-off in 15d. Supplementary UV-B radiation suppressed the increase
in growth components such as the number of leaves, the plant height and the fresh weight of aboveground plant parts, but did
not affect the fresh weight of roots. The ratio of the number of plants infected with pathogen to the total number of plants
was over 80% irrespective of light conditions. It was suggested that the defense response of spinach to this pathogen was
greatly influenced by the physiological state of aboveground plant parts resulting from supplementary UV-B radiation. 相似文献
124.
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
125.
Y. Kobayashi Yufuko Takahashi Satoshi Chikayama Motomi Ikeda Nobuhiko Uoshima Shinya Kimura Koji Tanaka Katuya Wada Masaru Ozawa Tatuo Sugano Naoyuki Maruo Motoharu Kondo 《Histochemistry and cell biology》1997,108(2):115-120
We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone
marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed
by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole
(DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were
changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional
to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when
megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls,
the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced
0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients,
the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore,
this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients.
Accepted: 29 April 1997 相似文献
126.
127.
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
128.
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
129.
It was previously reported thatHistoplasma capsulatum (Hc) yeast not only failed to stimulate a murine macrophage oxidative burst (OB), but they also blunted or abolished OB stimulation by a subsequent encounter with potent stimuli such as zymosan or phorbol 12-myristate 13-acetate (PMA). The present studies show that macrophage deactivation is proportional to the time of incubation and the dose of Hc yeast that induce the deactivated state. Hc yeast derived from a virulent strain (G217B) are more efficient inducers of macrophage deactivation than similar preparations derived from the avirulent Downs Hc strain. Yeast cells of two other pathogenic fungi,Candida albicans andCryptococcus neoformans are shown to stimulate rather than deactivate a macrophage OB. 相似文献
130.
Methionine sulfoximine (MSO) greatly reduced the carbon dioxideexchange rate (CER) of detached wheat (Triticum aestivvm L.cv Roland) leaves in 21% O2, but only slightly reduced it in2% O2. A supply of 50 mM NH4Cl had little effect on the CERirrespective of the O2 concentration. A simultaneous additionof glutamine and MSO protected against the inhibition of photosynthesisto a considerable extent and caused the accumulation of moreNH3 than did the addition of MSO alone. Fixation of 14CO2 in wheat leaves was inhibited by MSO treatmentin 22% O2, and there was decreased incorporation of 14G intoamino acids and sugars and increased label into acid fractions.The addition of MSO and glutamine together eliminated the effectof MSO on the photosynthetic 14CO2 fixation pattern. NH4Cl stimulatedthe synthesis of amino acids from 14CO2, especially the synthesisof serine in 22% O2. Our observations show that factors other than the uncouplingof photophosphorylation by accumulated NH3 may be responsiblefor the early stage of photosynthesis inhibition by MSO underphotorespiratory conditions.
1Present address: Department of Agricultural Chemistry, KyushuUniversity, Fukuoka 812 Japan.
2Also at U.S. Department of Agriculture, Agricultural ResearchService, Urbana, Illionois 61801, U.S.A. (Received September 13, 1983; Accepted February 2, 1984) 相似文献