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51.
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
52.
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
53.
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
54.
A new technique was devised for the dynamic detection of the axoplasmic transport of β-radioactively labeled materials in which a semiconductor radiation detector was used as the β-ray counter. The detector element is a silicon p-n junction diode and has a diameter of 2.0 mm. With this detector, the β-radioactive distribution of axoplasmic transport could be measured in an axon maintained physiologically without cutting nerves. This method makes possible determination of the transport rate using one bundle of peripheral nerves. The rate in the bullfrog was 6.4 mm per hour at 24.0 °C. Temperature effects on the bullfrog axoplasmic transport were also observed at different temperatures, ranging from 5.0 to 24.0 °C. At these temperatures the rate increased as an exponential function of temperature from 1.1 to 6.4 mm per hour. Within this temperature range, the Q10 is 2.5 and an Arrhenius plot of the natural logarithm of velocity versus the reciprocal of absolute temperature yielded an apparent activation energy of 14.8 Kcal. This technique offers great advantages in permitting direct study of the axoplasmic flow of the axon in a physiological condition. 相似文献
55.
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
56.
A new technique was devised for the dynamic detection of the axoplasmic transport of beta-radioactively labeled materials in which a semiconductor radiation detector was used as the beta-ray counter. The detector element is a silicon p-n junction diode and has a diameter of 2.0 mm. With this detector, the beta-radioactive distribution of axoplasmic transport could be measured in a axon maintained physiologically without cutting nerves. This method makes possible determination of the transport rate using one bundle of peripheral nerves. The rate in the bullfrog was 6.4 mm per hour at 24.0 degrees D. Temperature effects on the bullfrog axoplasmic transport were also observed at different temperatures, ranging from 5.0 to 24.0 degrees C. At these temperatures the rate increased as an exponential function of temperature from 1.1 to 6.4 mm per hour. Within this temperature range, the Q10 is 2.5 and an Arrhenius plot of the natural logarithm of velocity versus the reciprocal of absolute temperature yielded an apparent activation energy of 14.8 Kcal. this technique offers great advantages in permitting direct study of the axoplasmic flow of the axon in a physiological condition. 相似文献
57.
58.
1. A peptide which enhances ureogenesis in primary cultured hepatocytes of rats was isolated from a tryptic digest of bovine beta-casein. 2. The structure of the peptide was Ala-Val-Pro-Tyr-Pro-Gln-Arg which is located from 177th to 183rd residues from N-terminal of beta-casein. 3. The peptide also showed the activity to inhibit protein synthesis and protein degradation. 4. It also inhibited DNA synthesis of hepatocytes induced by insulin and/or epidermal growth factor. 相似文献
59.
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
60.
Azo compounds enable us to generate peroxyl radicals by thermal decomposition at a constant rate and at a desired site, that is, water-soluble compounds produce initiating radicals in an aqueous phase and lipid-soluble compounds initiate the oxidation within the membrane-lipid layer. Using these radicals generated in different sites, we oxidized red blood cell ghost membranes to study the relationships between alpha-tocopherol depletion, initiation of lipid peroxidation, and protein damage. When radicals were generated in the aqueous phase, the loss of membrane protein thiols was observed concurrently with the consumption of membrane tocopherol and after tocopherol was exhausted the peroxidation of membrane lipids occurred. On the other hand, when radicals were initiated within the lipid region, the oxidation of thiols and the formation of thiobarbituric acid-reactive substances were suppressed to give an induction period until tocopherol fell below a critical level. Our results indicate that the surface thiols of extrinsic proteins may compete with alpha-tocopherol for trapping aqueous radicals and spare tocopherol to some extent, whereas the oxidation of intrinsic buried thiols may commence due to lipid-derived radicals produced after tocopherol was consumed. In conclusion, alpha-tocopherol in the membrane can break the free radical chain efficiently to inhibit the lipid peroxidation. However, the effect of tocopherol on the inhibition of membrane protein damage, exhibited by the loss of thiols and the formation of high-molecular-weight proteins, would be different depending on the site of initial radical generation. 相似文献