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41.
42.
Morita Shimpei; Fukase Masami; Hoshino Kumiko; Fukuda Yoichi; Yamaguchi Masami; Morita Yuhei 《Plant & cell physiology》1994,35(7):1049-1056
A proteolytic activity directed against the 相似文献
43.
A cis-acting element and a trans-acting factor involved in the wound-induced expression of a horseradish peroxidase gene 总被引:2,自引:0,他引:2
Akiyoshi Kawaoka Tomohiro Kawamoto Masami Sekine Kazuya Yoshida Mitsuo Takano Atsuhiko Shinmyo 《The Plant journal : for cell and molecular biology》1994,6(1):87-97
The mechanisms that control the wound-induced expression of the prxC2 gene for horseradish peroxidase (HRP) have been investigated. Analysis of the regulatory properties of 5′-deleted promoters showed that a positive element involved in the response to wounding was located between −307 and −99 bp from the site of initiation of translation. In in vitro binding assays of tobacco nuclear proteins and DNA fragments of prxC2 promoter, the binding site was the Box 1 from −296 to −283 containing the CACGTG motif. To identify the functional role of Box 1, the prxC2 promoter that has been digested from the 5′ end to −289 with a disrupted Box 1 was fused to a reporter gene for β-glucuronidase (GUS). No induction of GUS activity was observed in transgenic tobacco plants with the prxC2(−289)/GUS construct. These data indicated that the expression of prxC2 in response to wounding required the Box 1 sequence from −296 to −283. Furthermore, a tobacco cDNA expression library was screened and a cDNA clone for a protein, designated TFHP-1, that bound specifically to the Box 1 sequence was identified. The putative TFHP-1 protein contains a basic region and leucine zipper (bZip) motif and a helix—loop—helix (HLH) motif. The mRNA for TFHP-1 was abundant in roots and stems, and it was not induced by wounding in leaves. In tobacco protoplasts, antisense TFHP-1 suppressed the expression of prxC2 (−529)/GUS. 相似文献
44.
A non-dialyzable extract of fresh spinach leaves exhibited a strong antioxidant activity towards oxidation of linoleic acid and suppressed the melanin formation of a mouse melanoma cell line, B16 melanoma 4A5, without any significant effect on the proliferation of cells. 相似文献
45.
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
46.
Tsukio Masegi Satoshi Nakamura Masami Fukuoka Kazuo Kitai Yataro Ichikawa Naoki Watanabe Yoshiro Niitsu 《Biotechnology letters》1993,15(11):1107-1110
Summary We prepared various TNF- derivatives by protein engineering techniques. Mutant 471, in which 7 N-terminal amino acids were deleted and Pro8Ser9Asp10 was replaced by ArgLysArg, had a 8-fold higher antitumor activity against mouse L929 cells than wild-type TNF-. The additional substitution of Ala156 or Leu157 by more hydrophobic amino acids enhanced the activity of mutant 471. These results suggested that the combinational mutations in the N- and C-terminal regions of TNF- are effective for the improvement of antitumor activity. 相似文献
47.
48.
Nitric Oxide Reversibly Suppresses Xanthine Oxidase Activity 总被引:10,自引:0,他引:10
Masami Fukahori Kohji Ichimori Hideyuki Ishida Hiroe Nakagawa Haruka Okino 《Free radical research》1994,21(4):203-212
The effects of nitric oxide (NO) on xanthine oxidase (XOD) activity and the site(s) of the redox center(s) affected were investigated. XOD activity was determined by superoxide (O2-) generation and uric acid formation. NO reversibly and dose-dependently suppressed XOD activity in both determination methods. The suppression interval also disclosed a dose-dependent prolongation. The suppression occurred irrespective of the presence or absence of xanthine; indicating that the reaction product of NO and O2-, peroxynitrite, is not responsible for the suppression. Application of synthesized peroxynitrite did not affect XOD activity up to 2 μM. Methylene blue, which is an electron acceptor from Fe/S center, prevented the NO-induced inactivation. The results indicate that NO suppresses XOD activity through reversible alteration of the flavin prosthetic site. 相似文献
49.
Tetsuo Hashimoto Eiko Otaka Jun Adachi Keiko Mizuta Masami Hasegawa 《Journal of molecular evolution》1993,36(3):282-289
Summary Using - and -hemoglobin sequences, we made a maximum likelihood inference as to the phylogenetic relationship among carnivores, including the two pandas, giant and lesser. Molecular phylogenetic studies up to 1985 had consistently indicated that the giant panda is more closely related to the bear than to the lesser panda. In 1986, however, a contradictory tree was constructed, using hemoglobins and so on, in which the two pandas link together (Tagle et al. 1986). In contrast to that tree, our conclusion supports the close relationship between bear and giant panda. The surface impression of a close relationship between the two pandas drawn from pairwise amino acid differences is explained by a rapid rate of hemoglobin evolution in the bear compared to that in the two pandas.Offprint requests to: T. Hashimoto 相似文献
50.
Noriyuki Suka Yoshinobu Shinohara Yasushi Saitoh Hisato Saitoh Kohei Ohtomo Masahiko Harata Edward Shpigelman Shigeki Mizuno 《Genetica》1993,88(2-3):93-105
About 65% of DNA in the chicken W chromosome has been shown to consist ofXhoI andEcoRI family repetitive sequences. These sequences showed remarkable delay in the electrophoretic mobility at low temperature
on a polyacrylamide gel. Three dimensional structures of the 0.7-kbXhoI and the 1.2-kbEcoRI family repeating units were estimated to be irregular solenoids using a computer program based on wedge angles of all the
16 dinucleotide steps. Fluorescencein situ hybridization demonstrated that these two family sequences were localized in a major heterochromatic body in an interphase
nucleus. Incorporation of bromodeoxyuridine into the W chromosome in the synchronous culture of MSB-1 cells occurred about
1 h later than the peak of S phase. The chromatin structure formed alongXhoI andEcoRI family sequences was suggested to be different from the total chromatin or chromatin containing the β-actin gene sequence
in that the linker DNA lengths of the former were significantly longer. Fractionation of theHaeIII-digested MSB-1 nuclei yielded a chromatin fraction in whichXhoI family sequences were partially enriched. Several DNA-binding proteins showing higher affinity for theXhoI family sequence were present in this fraction. 相似文献