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21.
Ota Yoko; Ario Takeshi; Hayashi Koji; Nakagawa Tsuyoshi; Hattori Tsukaho; Maeshima Masayoshi; Asahi Tadashi 《Plant & cell physiology》1992,33(3):225-232
Catalases purified from endosperm glyoxysomes and non-specializedmicrobodies from hypocotyls of castor bean seedlings differedin their specific activity [90164 and 0.894.9kunits (mg protein)1, respectively] and in their constituentsubunits [two subunits of 54 and 56 kDa for the endosperm enzymeand only one of 56 kDa for the hypocotyl enzyme]. Immunoblotanalysis also showed that particulate fractions from the endospermsand from etiolated and green cotyledons contained two catalasesubunits of 54 and 56 kDa, whereas such fractions from the hypocotylsand roots contained only the 56-kDa subunit. Leaf peroxisomesfrom green leaves had two catalase subunits of around 55 kDaeach. Results of translation in vitro indicated that the 54-and 56-kDa subunits were translated from distinct mRNAs andlevels of both mRNAs increased in the endosperms during germination,prior to increases in levels of catalase proteins. In the hypocotyls,the 56-kDa subunit seemed to be synthesized constitutively.
1Present addresses: YO, Toyota Central Institute, 31-9 Musashizuka,Nagabuchi, Nagakute, Aichi 480-11, Japan 相似文献
22.
Masao Suzuki Chizuru Tsuruoka Tatsuaki Kanai Takeshi Kato Fumio Yatagai Masami Watanabe 《Biological Sciences in Space》2003,17(4):302-306
We investigated the difference in cell-killing effect and mutation induction between carbon- and neon-ion beams in normal human cells. Carbon- and neon-ion beams were accelerated by the Riken Ring Cyclotron (RRC) at the Institute of Physical and Chemical Research in Japan. Cell-killing effect was measured as the reproductive cell death using the colony formation assay. Mutation induction at the HPRT locus was detected to measure 6-thioguanine-resistant clones. The mutation spectrum of the deletion pattern of exons of induced mutants was analyzed using the multiplex polymerase chain reaction (PCR). Cell-killing effect was almost the same between carbon- and neon-ion beams with similar linear energy transfer (LET) values, while there observed a large difference in mutation frequency. Furthermore, in the case of neon-ion beams 60% of mutants showed total deletions and 35-40% showed partial deletions, while 95-100% of carbon-ion induced mutants showed total deletions. The results suggest that different ion species may cause qualitative and quantitative difference in mutation induction even if the LET values are similar. 相似文献
23.
Takeshi Nishimura Setsuko Yamamoto Takaaki Yamamoto Munekiyo Kaneko Youichi Hara 《Prostaglandins & other lipid mediators》1996,51(2):149-159
The antithrombotic effect of topical application of the 3-oxamethano-prostaglandin (PG) I1 analog, SM-10902 in the microcirculation and in vitro antiplatelet functions of its active form SM-10906 were estimated in comparison with PGI2 and PGE1. In rat platelets, SM-10906 evoked accumulation of intracellular cyclic adenosine 3′,5′-monophosphate, and exhibited antiaggregatory and disaggregatory activities, which were all enhanced by the phosphodiesterase inhibitor theophylline. Additionally, SM-10906 was shown to inhibit platelet adhesion to collagen in human platelet-rich plasma. PGI2 and PGE1 also showed in vitro antiplatelet effects in the order of PGI2 > SM-10906 ≥ PGE1. SM-10902 exhibited a dose-dependent antithrombotic effect in the guinea pig mesenteric arteriole by a topical application, and this activity might be exerted by the antiplatelet functions of SM-10906. Although SM-10906, PGI2 and PGE1 also showed the antithrombotic effects, SM-10902 was the most potent. In conclusion, the present studies indicate that an external topical preparation of SM-10902 may be useful for the therapy of peripheral circulatory insufficiency. 相似文献
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26.
Lemna paucicostata Hegelm. T-101, a short-day plant, flowers when plants preirradiated with red light (R) for 24 h are subjected to inductive darkness for 72 h followed by two short-day cycles (6 h R+ 18 h dark). However, flowering is inhibited by blue-or far-red-light pulses applied at the beginning of the inductive dark period. These inhibitory light effects are fully reversible by a R pulse. The action spectra for the inhibitory light effect and for its reversal show that the light pulses act exclusively through phytochrome. It is concluded that a low level of Pfr at the beginning of the inductive dark period prevents flowering.Abbreviations R
red (light)
- B
blue (light)
- FR
far-red (light) 相似文献
27.
28.
Matsuo Tsukasa 《Journal of plant research》1983,96(2):127-133
The late-glacial logistic decline of spruce (Picea) populations (the intrinsic growth rate,r in yr?1=?0.0015) was progressively delayed toward cooler sites in Japan; spruce populations expanded asymptotically (r=0.0040?0.0045) in Sakhalin early in the Holocene. Such a time-transgressive range shift in spruce distribution, covering a wide latitudinal range (ca. 35–50°N), implies that the regional temperature rise was not instantaneous, but was rapid, being 0.0015–0.0025 C yr?1 from 13,000 to 10,000 years B.P. Spruce populations increased in response to Neoglacial cooling only at the margin of its distribution (r=0.0036), but then declined logistically 1,000 years B.P. (r=?0.0022). 相似文献
29.
Protein kinase C (PKC) from a human megakaryoblastic leukemic cell line (MEG-01) was resolved into two fractions by hydroxyapatite column chromatography, which are indistinguishable from the brain type II (beta I/beta II) and type III (alpha) subspecies, by biochemical and immunoblot analysis. In the presence of both phosphatidylserine and diacylglycerol, several free unsaturated fatty acids (FFA's), such as arachidonic, oleic, linoleic and linolenic acids, further enhanced the enzyme activation, and allowed the enzyme to exhibit almost full activity at nearly basal levels of Ca2+ concentration. The concentration of unsaturated FFA's giving rise to the maximum enzyme activation was around 2 x 10(-5) M. Palmitic and stearic acids were inactive. The result implies that, in addition to diacylglycerol, the receptor-mediated release of unsaturated FFA's from membrane phospholipids may also take part in the activation of PKC. 相似文献
30.
N-terminally extended form of C-type natriuretic peptide (CNP-53) identified in porcine brain 总被引:3,自引:0,他引:3
N Minamino K Kangawa H Matsuo 《Biochemical and biophysical research communications》1990,170(2):973-979
C-type natriuretic peptide of 22 residues (CNP-22) is very recently identified in porcine brain as a third member of the mammalian natriuretic peptide family (1). Using a radioimmunoassay system newly established for CNP-22, we searched for CNP-related peptides in porcine brain. In addition to CNP-22, one major form of immunoreactive CNP was detected in porcine brain extracts, being isolated by immunoaffinity chromatography and reverse phase high performance liquid chromatography. By microsequence analysis, the peptide was deduced to be a 53-amino acid peptide carrying a CNP-22 sequence at the C-terminus, and was designated C-type natriuretic peptide-53 (CNP-53). CNP-53 was found to be a major molecular form of CNP in porcine brain. 相似文献