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51.
52.
Control of cocklebur seed germination by nitrogenous compounds : Nitrite, nitrate, hydroxylamine, thiourea, azide and cyanide 总被引:3,自引:0,他引:3
Esashi Yohji; Ohhara Yuuko; Okazaki Makiko; Hishinuma Kohya 《Plant & cell physiology》1979,20(2):349-361
Germination of non-dormant upper cocklebur (Xanthium pinsylvanicumWallr.) seeds was stimulated by not only CS(NH2)2 but also NH2OH,KCN and NaN3. This stimulation was not via the enhancement ofaerobic C2H4 production. NH2OH, KCN and NaN3 in certain concentrationspromoted the initial growth of axial and/or cotyledonary parts,but the degree of growth promotion by NH2OH, NaN3 and KCN wasslight compared with that by CS(NH2)2. As in the case of CS(NH2)2,however, the germinationstimulating effect of NH2OH disappearedrapidly as the preceding imbibition period was prolonged. Incontrast, KCN and NaN3 were still effective in stimulating thegermination of aged seeds maintained on a water substratum,as previously seen with anaerobiosis. Anaerobic induction wasenhanced not only by NaN3 and KCN but also by NH2OH, KNO3, KNO2CO(NH2)2 and CS(NH2)2 applied during the anaerobic treatment,but without causing an increase in anaerobic production of C2H4.Furthermore, KCN and NaN3, given prior to the anaerobic treatmentacted additively with anaerobic induction. The germination-stimulatingactions of nitrogenous compounds are discussed in comparisonwith those of C2H4 and anaerobiosis. (Received May 6, 1978; ) 相似文献
53.
J. Bilen M. E. Ittel C. Niedergang H. Okazaki P. Mandel 《Neurochemical research》1981,6(12):1253-1263
Two different preparations isolated from beef cerebrum have been used to compare the polyadenosine diphosphate ribose (polyADPR) polymerase activities in neuronal and glial nuclei: (1) nuclear suspensions (with or without DNase I treatment), and (2) 1 M NaCl nuclear extracts (soluble enzyme). The DNAse I treatment of nuclei and the solubilization of polyADPR polymerase by 1 M NaCl enhances the polyADPR polymerase activity. The polyADPR polymerase activity is similar in neuronal and glial nuclear suspensions, while the neuronal soluble enzyme activity is significantly higher than that of the glial soluble enzyme. Evidence is presented that the difference in soluble enzyme activities is not due to the effects of DNA or degrading enzymes. Some activating factor(s) seem to be present in neuronal soluble extracts, while both inhibiting and activating factor(s) seem to be present in glial soluble extracts. 相似文献
54.
Toshio Okazaki Masakazu Watanabe Kenya Mizuguchi Kazumi Hosoya 《Ichthyological Research》1991,38(2):133-140
Two types of the dark chub,Zacco temmincki, collected from 10 river systems in Japan were genetically characterized at 27 protein coding loci using starch-gel electrophoresis. They were fixed for different alleles at 13 loci. No hybrid individuals were observed, even in specimens collected in stations where both types appear sympatrically, indicating that each type of the dark chub represents a distinct species. 相似文献
55.
Effect of 24,25-dihydroxyvitamin D3 in osteoclasts. 总被引:1,自引:0,他引:1
T Matsumoto H Yamato R Okazaki M Kumegawa E Ogata 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1992,200(2):161-164
Previous results demonstrated that the administration of pharmacological doses of 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) to animals reduces bone resorption and increases bone volume with a decrease in osteoclast number. In order to clarify whether 24,25(OH)2D3 has an effect to inhibit osteoclastic bone resorption, the effect of 24,25(OH)2D3 on the formation and function of osteoclastic cells was examined in vitro. Treatment of hemopoietic blast cells, which are progenitors of osteoclasts, with parathyroid hormone (PTH) or 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) stimulated the formation of osteoclast-like multinucleated cells in a dose-dependent manner. Although 24,25(OH)2D3 in itself had little effect on osteoclast-like multinucleated cells formation, it inhibited the stimulatory effect of PTH on the formation of osteoclastic cells. In addition, 24,25(OH)2D3 also inhibited the stimulation of resorption pit formation by osteoclasts under stimulation with PTH. In contrast, 1,25(OH)2D3 stimulated the formation and function of osteoclastic cells even at low concentrations, and the effect was additive to PTH. These results could not be explained by either an agonistic or antagonistic effect of 24,25(OH)2D3 on 1,25(OH)2D3, and are consistent with the assumption that 24,25(OH)2D3 has a unique inhibitory effect on the formation and function of osteoclasts. Because 24,25(OH)2D3 is shown to stimulate the degradation of 1,25(OH)2D3 and because the formation of 24,25(OH)2D3 is stimulated by 1,25(OH)2D3 not only in the kidney but also in many of its target tissues, including bone, the inhibitory effect of 24,25(OH)2D3 on osteoclastic bone resorption may play a role in the local modulation of the actions of osteotropic hormones in bone. 相似文献
56.
Toshiro Oridate Haruhisa Atsumi Satishi Ito Hajime Araki 《Plant Cell, Tissue and Organ Culture》1992,29(1):27-30
Significant differences in somatic embryogenesis from melon seeds were observed among 18 cultivars; especially, cultivars Earl's Favorite and Barnett which produced a large number of somatic embryos. F1 seeds were obtained by reciprocal crosses between cultivars. Some lines produced a large number of somatic embryos whereas others showed no or poor embryogenic response. Most of the F1 seeds formed somatic embryos. The frequency of somatic embryogenesis decreased as compared to the parents with the highest potential. Transfer of the frequency of somatic embryogenesis from superior responding cultivars to inferior cultivars was proved. It was difficult to determine the mode of inheritance of somatic embryogenesis because there was a large variation in the range of somatic embryogenesis from F2 seeds, and cytoplasmic effect was recognized in certain combinations.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- BAP
6-benzylaminopurine 相似文献
57.
58.
59.
S Asakura H Hirata H Okazaki T Hashimoto-Gotoh M Matsuda 《The Journal of biological chemistry》1990,265(9):5135-5138
In the presence of a monoclonal antibody raised against the human thrombin-antithrombin III complex, the reaction between thrombin and antithrombin III proceeded to form preferentially a two-chain form of the inhibitor rather than to follow the major pathway of stable acyl complex formation. We thus propose the term "switching antibody" for an antibody that switches the enzyme-inhibitor reaction (Asakura, S., Matsuda, M., Yoshida, N., Terukina, S., and Kihara, H. (1989) J. Biol. Chem. 264, 13736-13739). By analyzing a CNBr fragment of the thrombin-antithrombin III complex that reacts with the antibody we localized the epitope for the antibody to a strongly hydrophobic residue 382-386 peptide segment, Ala-Ala-Ala-Ser-Thr, of the inhibitor, which is also contiguous with a hydrophobic amino acid Ala at its carboxyl terminus. This particular region should be cryptic in nascent antithrombin III, but could have been exposed to provide the reactive site for the antibody at an early stage of the reaction. Thereby a conformational change may have been induced at or near the reactive site of the complex, facilitating hydrolysis of the inhibitor by the enzyme. Interestingly, this hydrophobic region is highly conserved among members of the serpin family. 相似文献
60.
S I Tu H Okazaki F Ramirez E Lam J F Marecek 《Archives of biochemistry and biophysics》1981,210(1):124-131
Compounds made from the reaction of fluorescamine with simple primary amines and with mycosamine-containing macrolide antibiotics (e.g., amphotericin B) are used to investigate possible interactions between ATPase and respiration enzymes in rat liver mitochondria. The following observations have been made. (1) The acyclic form of the benzyl amine-fluorescamine compound stimulates the ATPase-linked inorganic phosphate formation, and this stimulation is not affected by rotenone, antimycin A, and potassium cyanide. In contrast, the respiratory inhibitors are able to prevent the stimulation of ATPase activity that is caused by conventional uncouplers e.g., 2,4-dinitrophenol. (2) The acyclic form of the amphotericin B-fluorescamine compound has no effect on ATPase-linked inorganic phosphate formation rate. However, in the presence of the antibiotic-fluorescamine compounds, the respiratory inhibitors are no longer able to prevent the uncoupler-stimulated ATPase activity. (3) The amine-fluorescamine modifiers have no effect on rotenone-sensitive NADH-cytochrome c reductase, on succinate-cytochrome c reductase, and on cytochrome oxidase in submitochondrial particles. (4) The amine-fluorescamine modifiers decrease the rate of the ATP-driven NAD+ reduction by succinate in submitochondrial particles. (5) The amine-fluorescamine modifiers inhibit the stimulation of respiration that is caused by conventional uncouplers, although the modifiers have no effect on the kinetics of the proton influx induced by uncouplers. The data are consistent with the hypothesis that the ATPase-linked and respiration-linked proton pumps may interact directly with each other, and this step establishes the mutual regulation between ATPase and respiratory activities. 相似文献