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11.
ent-Kaurene Synthesis and Endogenous Levels of Gibberellins in a Shoot Forming Tobacco Crown Gall Tissue 总被引:1,自引:0,他引:1
Mettrie Ren?e; de Greef Jan; Nakagawa Sachiko; Sakurai Akira 《Plant & cell physiology》1988,29(5):777-784
The in vitro ent-Mcaurene synthesizing capacity, as well asthe endogenous GA content of shoot-forming tobacco crown gallsinduced by a nopaline-type Ti plasmid, was studied. For determinationof the ent-kaurene synthesizing capacity, an HPLC procedurepreceded by sample clean-up was used and the GA content wasexamined by GC-SIM. Kaurene synthesis reached a maximum at thebeginning of the logarithmic phase of growth. There was a clearcorrelation between the ent-kaurene synthesizing capacity andthe content of C20-GAs. It seems that gibberellin synthesisis related to growth and development of the tissue. The natureof the GAs identified suggests, that the GA metabolism mightbe an unusual one. (Received October 12, 1987; Accepted April 11, 1988) 相似文献
12.
Levels of IAA, Cytokinins, ABA and Ethylene in Rice Plants as Affected by a Gibberellin Biosynthesis Inhibitor, Uniconazole-P. 总被引:1,自引:0,他引:1
Izumi Kazuo; Nakagawa Sachiko; Kobayashi Masatomo; Oshio Hiromichi; Sakurai Akira; Takahashi Nobutaka 《Plant & cell physiology》1988,29(1):97-104
Effects of uniconazole-P, a triazole-type growth retardant,on endogenous levels of IAA, cytokinins, ABA and ethylene inrice seedlings were investigated. Endogenous levels of IAA andABA were similar between control and uniconazole-P-treated riceshoots. Evolution of ethylene was promoted slightly, being 1.8times greater under 0.3 ppm uniconazole-P treatment than thatof control. The most obvious effect was the increase of trans-Zand trans-RZ in shoots. Shoots treated with uniconazole-P (10mg/m2 nursery box) contained 3.4 times and 3 times more trans-Zand trans-RZ than control, respectively. No significant differencesof cytokinin levels were recognized in roots except for cis-RZ.The increase of ethylene and active forms of cytokinins, andthe decrease of gibberellin in the shoots may be the basis forphysiological phenomena caused by uniconazole-P, namely thepromotion of flowering in woody plants and the enhancement offemaleness in cucumber. (Received September 9, 1987; Accepted October 20, 1987) 相似文献
13.
Hypocotyl growth of seedlings of dark-grown squash (Cucurbitamaxima Duch.) was greatly reduced by the addition of 60mM polyethyleneglycol (PEG) to hydroponic solution (water stress). Apoplastic solution (A) and cell sap (C) were separately collectedfrom the hypocotyl segments by a centrifugation method. Theosmotic potentials of A (A) and C (c), and (=cA) ofstressed hypocotyls were always lower than those of unstressedhypocotyls. Suction force was measured by immersing the segments into solutionsof different concentrations of mannitol. Suction force was significantlycorrelated with C (r= 0.99). The mechanical properties of the cell wall of hypocotyl segmentswere measured by stressrelaxation technique. Minimum stressrelaxation time (To), relaxation rate (R) and residual stressof unstressed hypocotyls were low during the growth period andincreased when the growth ceased. To and R of stressed hypocotylsdecreased one day after the stress treatment, but the residualstress was not decreased by the water stress throughout theexperiment. These results suggest that the suppressed growth of dark-grownsquash hypocotyls under water stress was due neither to thereduction of the osmotic potential difference between innerand outer space of the cell, nor to the decrease in suctionforce, but was partly due to the unchanged mechanical propertiesof the cell wall, as represented by one stress-relaxation parameter,residual stress. (Received February 5, 1988; Accepted September 8, 1988) 相似文献
14.
Matuo Y Nishi N Muguruma Y Yoshitake Y Masuda Y Nishikawa K Wada F 《Cytotechnology》1988,1(4):309-318
Among several detergents, a zwitterionic detergent, 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS), was found to be least cytotoxic for cultured mammalian cells. CHAPS improved the activity recovery and elution profile of crude and purified fibroblast growth factors (FGFs) during chromatographies. Diluted preparations of FGFs were stabilized by CHAPS against the loss during storage. Amino acid sequence analysis was not disturbed by CHAPS. CHAPS was removable by reversed-phase high-performance liquid chromatography. These results indicate that CHAPS is useful as a non-cytotoxic stabilizing agent in purification of various kinds of bioactive polypeptides.Abbreviations -MEM
Alpha Modification of Eagle's Minimal essential medium
- CHAPS
3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate
- CHAPSO
3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propane sulfonate
- CS
Calf Serum
- EGF
Epidermal Growth Factor
- FGF
Fibroblast Growth Factor
- HPLC
High-Performance Liquid Chromatography
- NGF
Nerve Growth Factor
- NOG
1-O-n-octyl--D-glucopyranoside
- NP-40
Nonidet P-40
- PBS
Phosphate-Buffered Saline
- SB 12
3-(dodecylmethylammonio)-1-propane sulfonate
- SDS
Sodium Dodecyl Sulfate
- TGF- and
Transforming Growth Factor type and 相似文献
15.
Yokoyama Eiichi; Murakami Akio; Sakurai Hidehiro; Fujita Yoshihiko 《Plant & cell physiology》1991,32(6):827-834
Stability of thylakoid components under supra-high irradiancewas studied with the cyanophyte Synechocystis PCC 6714. Theactivity of overall photosynthesis was quickly inactivated (T1/2=20min) under supra-high irradiance (300 W m2, white light).In parallel with the inactivation of photosynthesis, QA in PSII was also inactivated. Both inactivations were acceleratedby chloramphenicol (CAP) addition. The reactivation of PS IIrequired weak irradiation and was suppressed by CAP. However,PS I measured as P700 was very stable. The level of PS I measuredas P700 was not significantly reduced by the irradiation for12 h even in the presence of CAP while the level of Cyt b559,component of PS II, was decreased markedly. The function ofPS I before and after supra-high irradiation with CAP was examinedby comparing sizes of P700 oxidation induced by a short flash,by a continuous light, and by determination of O2-and ferredoxin-reduction.No difference was observed in PS I actions before and afterthe irradiation treatment. These results indicate that the PSI complex is very tolerant of supra-high irradiation. However,the cells grown under supra-high irradiance contained much fewerPS I and PS II complexes than Cyt b6f complexes. Theformer levels were reduced to a half to one fourth of thosebefore growth while the level of Cyt b6f complex wasnot reduced so much. A possible mechanism for changes in thylakoidcomposition under supra-high irradiation was discussed. (Received February 16, 1991; Accepted June 12, 1991) 相似文献
16.
Effects of indole-3-acetic acid (IAA) on the mechanical properties of cell walls and structures of cell wall polysaccharides in outer and inner tissues of segments of dark grown squash (Cucurbita maxima Duch.) hypocotyls were investigated. IAA induced the elongation of unpeeled, intact segments, but had no effect on the elongation of peeled segments. IAA induced the cell wall loosening in outer tissues as studied by the stress-relaxation analysis but not in inner tissues. IAA-induced changes in the net sugar content of cell wall fractions in outer and inner tissues were very small. Extracted hemicellulosic xyloglucans derived from outer tissues had a molecular weight about two times as large as in inner tissues, and the molecular weight of xyloglucans in both outer and inner tissues decreased during incubation. IAA substantially accelerated the depolymerization of xyloglucans in outer tissues, while it prevented that in inner tissues. These results suggest that IAA-induced growth in intact segments is due to the cell wall loosening in outer tissues, and that IAA-accelerated depolymerization of hemicellulosic xyloglucans in outer tissues is involved in the cell wall loosening processes. 相似文献
17.
Novel Technique for Measuring Tissue Firmness within Tomato (Lycopersicon esculentum Mill.) Fruit
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Developmental changes of tomato (Lycopersicon esculentum) fruit tissues during maturation were analyzed by a physically defined method (stress-relaxation analysis). The tip of a conical probe connected to a load sensor was positioned on the cut surface of a sliced tomato fruit, and the decay of the imposed stress was monitored. Stress-relaxation data thus obtained were used for the calculation of three stress-relaxation parameters. Different zones within tomato fruit harvested at six different ripening stages were analyzed. One of the stress-relaxation parameters, minimum stress-relaxation time (T0), decreased as the fruits matured. The decrease in T0 was first found in the core of the carpel junction within the endopericarp at the blossom end during the breaker stage. The decrease in T0 progressed from the blossom end, through the equatorial region and finally throughout the shoulder, as the fruit matured. In mature green fruit, T0 values within the placenta and the proximal carpel junction were lower than those by other parts of the fruit. For all measurements the maximum stress-relaxation time was not substantially changed during maturation, nor were their changes observed in different regions of the fruit. The observed relaxation rate was therefore correlated with softening. The results indicate that fruit softening may be physically associated with the stress-relaxation parameter, T0, and the extent of softening is a function of position within the fruit. Decreases in T0 value appear to be correlated with the reported regional variation in the appearance of polygalacturonase. 相似文献
18.
19.
The present study was conducted to explore whether or not manganese effect on brain monoamine oxidase (EC 1.4.3.4) is subject to hereditary genetic amplification. Mice of both sexes were given manganese through four generations, and the enzyme activity was measured in the cerebral cortex, cerebellum, hypothalamus and hippocampus of each of the generations except for the third, whose activity we were not in a position to measure. Intrinsic enzyme activity was highest in the cerebellum, and was followed by those in the cerebral cortex and hypothalamus. The activity in the hippocampus was the lowest. Manganese administration greatly stimulated the activity in the cerebellum. However, as generation succeeded, the level of susceptibility to manganese gradually declined. Manganese concentration in pooled suborgan fractions proved to be, in every case, higher in the cerebral cortex, cerebellum and hippocampus and lower in the hypothalamus. No indication was found that the manganese effect is genetically inherited. 相似文献
20.
Spermidine synthase from rat ventral prostate was inhibited by 2-mercaptoethylamine (MEA). Inhibition of spermidine synthase by MEA was competitive with respect to one of the substrates putrescine, but not competitive with respect to the other substrate decarboxylated S-adenosylmethionine. MEA markedly depressed spermidine and spermine contents in human erythroid leukemia K562 cells, suggesting that these changes resulted from the inhibitory effect of MEA on spermidine synthase in situ. 相似文献