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1.
Quantitative Analysis of Endogenous Gibberellins in Normal and Dwarf Cultivars of Rice 总被引:7,自引:0,他引:7
Kobayashi Masatomo; Sakurai Akira; Saka Hitoshi; Takahashi Nobutaka 《Plant & cell physiology》1989,30(7):963-969
Endogenous levels of gibberellins in shoots and ears of twodwarf rice (Oryza sativa L.) cultivars, Tan-ginbozu (dx mutant)and Waito-C (dy mutant), were analyzed and compared with thoseof normal rice cultivar, Nihonbare. The endogenous levels of13-hydroxylated gibberellins in Tan-ginbozu were much lowerthan those in Nihonbare. In Waito-C, the levels of GA19 andGA20 in the shoots were higher but that of GA1 was lower thanthe levels of these gibberellins in Nihonbare. These resultssupport the hypothesis that the dy gene controls the 3ß-hydroxylationof GA20 to GA1 while the dx gene controls a much earlier stepin the gibberellin biosynthesis. Our results indicate that GA1is the active gibberellin that regulates the vegetative growthof rice. The endogenous levels of GA4 in the ears of the twodwarf cultivars of rice were higher than the level of GA4 inthe ears of the normal cultivar, Nihonbare suggesting that thebiosynthesis of gibberellin is not blocked in the anthers ofthe dwarf rice. (Received April 27, 1989; Accepted July 12, 1989) 相似文献
2.
Nobutaka Fujii Akira Otaka Susumu Funakoshi Toshihiro Watanabe Hiromitsu Arai Kiyoshi Bessho Haruaki Yajima 《Journal of Protein Chemistry》1988,7(2):151-156
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc
t-butyloxycarbonyl
- Z(OMe)
p-methoxybenzyloxycarbonyl
- MBzl
p-methoxybenzyl
- Acm
acetamidomethyl
- Bzl
benzyl
- Ad
l-adamantyl
- tBu
t-butyl
- TFA
trifluoroacetic acid
- TFMSA
trifluoromethanesulfonic acid
- TMSOTf
trimethylsilyl trifluoromethane sulfonate 相似文献
3.
Ishikawa Keiko; Kamada Hiroshi; Yamaguchi Isomaro; Takahashi Nobutaka; Harada Hiroshi 《Plant & cell physiology》1988,29(3):461-466
Carrot and tobacco plants were transformed with Agrobacteriumtumefaciens harboring wild-type, aux or cyt Tiplasmids. In tobacco, these wild and mutant Ti plasmids inducedthe formation of non-morphogenic galls, galls with shoots, andgalls with roots, respectively. In carrot, however, transformationwith any of these plasmids resulted in only the formation ofamorphous tumors. Determination of IAA and cytokinin contentsshowed that in tobacco, significantly high amounts of cytokininsor IAA are present in the cells transformed with Ti plasmidspossessing cytokinin or IAA biosynthetic genes, respectively.In carrot, cytokinin contents were also high in the cells transformedwith Ti plasmids having cytokinin biosynthetic genes, whereasIAA contents of the cells were similar regardless of the plasmidsused for transformation. These results suggest that the mechanism regulating IAA metabolismmay be different in tobacco and carrot. (Received June 25, 1987; Accepted February 1, 1988) 相似文献
4.
Identification of Cytokinins in Root Exudate of the Rice Plant 总被引:4,自引:0,他引:4
Murofushi Noboru; Inoue Ayumu; Watanabe Naoharu; Ota Yasuo; Takahashi Nobutaka 《Plant & cell physiology》1983,24(1):87-92
Cytokinins, cis-zeatin and cis- and (trans-ribosylzeatin, wereidentified in the root exudate of the rice plant (Oryza sativa,indica cultivar IR-24) after several chromatographic separationsand combined gas-liquid chromatography-selected ion monitoring(GC-SIM) analysis. The presence of trans-zeatin ribotide wassuggested by enzyme hydrolysis, subsequent chromatographic separationand GC-SIM. The comparatively high content of the ribotide inthe root exudate suggests the form of cytokinins to be transportedfrom roots to other parts in the rice plant. (Received July 22, 1982; Accepted November 25, 1982) 相似文献
5.
Green Lavandula vera callus that produced biotin was preservedsuccessfully in liquid nitrogen for up to 3 weeks. We foundthat the callus recovered after the freeze-preservation, retainingnot only the biosynthetic capability for biotin but also differentiationpotentials such as chloroplast development and plantlet formation.The significance of retention of the metabolic and differentiationpotentials of the callus is discussed in terms of the freeze-preservationof plant genetic resources.
* This study is dedicated to the late Professor J. Ashida. (Received September 1, 1982; Accepted November 5, 1982) 相似文献
6.
7.
Soh Chang-Ho; Kamiya Yuji; Yoshida Shigeo; Yamane Hisakazu; Takahashi Nobutaka 《Plant & cell physiology》1994,35(7):1037-1042
Oryzains, cysteine proteinases of rice seeds, are induced byGA3 in germinating rice seeds [Abe et al. (1987) Agric. Biol.Chem. 51: 1509]. The effects of GA1, GA3, GA4, GA9, and GA20on the production of oryzain and -amylase were investigatedin embryoless half- and whole-seeds of rice (cv. Nipponbare).When gibberellins (GAs) were incubated with embryoless half-seeds,GA1, GA3 and GA4 induced oryzain and -amylase, but GA9, andGA20 did not. GA9 and GAM induced oryzain and -amylase productionin whole seeds, but this production was inhibited by the simultaneousapplication of prohexadione, an inhibitor of 2ß- and3ß-hydroxylation of GAs. Prohexadione did not inhibitthe activities of oryzain and -amylase induced by GA1. Theseresults suggest that GAs possessing the 3ß-hydroxylgroup induce activities of oryzain and -amylase in rice seedsand that GA9 and GA20 have activity only after they are convertedmetabolically to active GAs, probably GA4 and GA1, respectively.GA1, was more active than GA4 in both half seeds and wholeseeds incubation. Oryzain and -amylase activities induced byGA4 were significantly inhibited in the presence of 104M prohexadione. This suggests that the conversion of GA1, toGA4 (13-hydroxylation) might be inhibited at a high dose ofprohexadione in whole seeds.
4Present address: Institute of Food Development, Kyung Hee University,Suwon 449-701, Korea 相似文献
8.
Toyomasu Tomonobu; Yamane Hisakazu; Yamaguchi Isomaro; Murofushi Noboru; Takahashi Nobutaka; Inoue Yasunori 《Plant & cell physiology》1992,33(6):695-701
Four 13-hydroxygibberellins, gibberellin A1 (GA1), 3-epi-GA1,GA19 and GA20 were identified by full-scan GC/MS in extractsof lettuce seedlings (Lactuca sativa L. cv. Grand Rapids). Theresults suggest that the early-13-hydroxylation biosyntheticpathway to GA1 functions in the lettuce seedlings. It was alsofound that GA1 is active per se in the control of hypocotylelongation in lettuce seedlings. To investigate the relationshipbetween control by light of hypocotyl elongation and levelsof endogenous GAs in lettuce, endogenous levels of GAs werequantified by radioimmunoassay in seedlings that had been grownfor 5 days in the dark (5D) and in those that had been grownfor 4 days in the dark and then under white light for 1 day(4D1L). The endogenous level of GA1 in the upper and lower partsof hypocotyls in 5D seedlings was about four times higher thanthat in 4D1L seedlings. The response of explants (hypocotylsegments with cotyledons) from dark-grown seedlings to GA1 isknown to be similar in the dark and under white light when theexplants are treated with inhibitors of the biosynthesis ofGA. Therefore, the above information suggests that the highlevel of GA1 in hypocotyls of dark-grown seedlings is responsiblefor the rapid elongation of hypocotyl, while irradiation bywhite light decreases the endogenous level of GA1 in the hypocotylswith a resultant decrease in the rate of hypocotyl elongation. (Received March 13, 1992; Accepted May 21, 1992) 相似文献
9.
Wei Zhang David J. Chapman Bernard O. Phinney Clive R. Spray Hisakazu Yamane Nobutaka Takahashi 《Journal of phycology》1991,27(1):87-91
Combined gas chromatography-mass spectrometry (GCMS) was used to identify and quantify specific cytokinins from Porphyra perforate J. Ag. and Sargassum muticum (Yendo) Fensh. The level of isopentenyladenosine was estimated to be 0.6 μ·kg?1 fresh weight in Porphyra and 0.9 μ·kg?1 fresh weight in Sargassum. The level of cis-zeatin riboside was estimated to be 0.2 μ·kg?1 fresh weight in Sargassum. This is the first definitive identification of a cytokinin from a red alga, and the second report from a brown alga. 相似文献
10.
Hiroshi Nakada Mizue Inoue Nobuhiro Tanaka Nobutaka Wakamiya Ikuo Yamashina 《Glycoconjugate journal》1995,12(3):356-359
We have measured glycosyltransferase activities of SupT1 cells, a T-lymphoid cell line shown to react with autoantibodies in the sera of many HIV patients. Since considerable -N-acetylgalactosaminyl-transferase and 1, 3 galactosyl-transferase activities were found in SupT1 cells, at least the O-glycan core 1 structure can probably be synthesized. FACS analysis using an anti-T monoclonal antibody showed expression of the T antigen (Gal 1-3 GalNAc). Glycoproteins with the T antigen were isolated by immunoprecipitation with the anti-T antibody from a SupT1 cell lysate labelled metabolically with3H-glucosamine and then analysed by SDS-PAGE. It was revealed that the precipitate contained a glycoprotein with a molecular weight corresponding to that of leukosialin. O-glycans were prepared from the immunoprecipitate by alkaline-borohydride treatment and then fractionated on Bio-Gel P-2, GalNAcOH and Gal-GalNAcOH being identifiedinter alia. These results suggest that an anti-T antibody may be included in the autoantibodies found in HIV-1 infected individuals. 相似文献