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21.
Changes in synthetic activity of cell walls during the cell cycle in a synchronous culture of Catharanthus roseus 总被引:1,自引:0,他引:1
The incorporation rates of [14 C] glucose into various fractions of the cell walls and into the sugar constituent of each fraction were investigated in a synchronous culture of Catharanthus roseus (L.) G. Don in order to elucidate the synthetic aspects of the cell walls during the cell cycle. Changes in the incorporation of radioactivity were closely correlated with changes in the amount of each cell wall fraction as well as with those in sugar composition as reported previously (S. Amino et al. Physiol. Plant. 60: 326–332, 1984). The specific activity of galactose was higher than that of other sugars throughout the cell cycle, and a temporary increase in the incorporation of radioactivity into all cell wall fractions except cellulose was observed just before the increase in cell numbers. The synthetic activities may play key roles in the regulation of cell wall polysaccharide dynamics during the cell cycle. 相似文献
22.
Chromoplast DNA was isolated from ripe-red tomato fruits, andits structure compared with that of chloroplast DNAs from maturegreen fruits and leaves. There was a good correspondence betweenthe structures analyzed by BamHI or EcoRI digestion and by hybridizationwith a probe for the gene of the ribulose 1,5-bisphosphate carboxylase/oxygenaselarge subunit.
1 Present address: Koryo International College, Nisshin, Aichi470-01, Japan. (Received November 5, 1984; Accepted February 6, 1985) 相似文献
23.
M Kinoshita M Okazaki H Kato T Teramoto T Matsushima C Naito H Oka I Hara 《Journal of biochemistry》1984,95(4):1111-1118
A simple and rapid method for the analysis of apolipoproteins in high density lipoprotein (HDL) by high performance liquid chromatography (HPLC) has been developed (Kinoshita et al. (1983) J. Biochem. 94, 615-617). With this method, using a sodium phosphate buffer containing 0.1% sodium dodecyl sulfate (SDS) as an eluent, apolipoproteins can be analyzed from a very small amount of HDL fraction without delipidation using organic solvents. Separation profiles of apolipoproteins by this method were examined using several techniques. The elution pattern monitored by A280 can give precise quantitative as well as qualitative information about size-distribution of apolipoproteins, except for the apo C group. Moreover, separation of apo E from apo A-I was found to be improved by column elongation. 相似文献
24.
Yohei Hashimoto Hiroyuki Ishizone Midori Moriyasu Kazuko Kawanishi Atsushi Kato Masaru Ogura 《Phytochemistry》1984,23(8):1807-1808
Three oleanane triterpenes were isolated from the roots of Periandra dulcis,and identified as 3β-hydroxy-25-al-olean-18-en-30-oic acid (periandric acid I), 3β-hydroxy-25-al-olean-12-en-30-oic acid (periandric acid II) and 3-oxo-25-hydroxy-olean-12-en-30-oic acid. The former two compounds (periandric acids I and II) were identical with the aglycones obtained by hydrolysis of periandrin I and II, respectively and the latter one was a new triterpene. 相似文献
25.
Kimitaka Yakura Atsushi Kato Shigeyuki Tanifuji 《Molecular & general genetics : MGG》1984,193(3):400-405
Summary The DNA fragments including the whole large spacer region of Vicia faba rDNA were cloned in plasmid pBR325. Sixteen clones were classed into five groups which differed from each other in the lengths of the rDNA inserts. Physical maps of these length variants cloned were constructed using EcoRI, SalI, HpaI, MluI and AccI and evidence was obtained that the length heterogeneity was due mainly to the differing number of 325 base pairs (bp) subrepeating elements in the large spacer. Sequence analysis of this subrepeating element revealed that it consisted of a duplet of an approximately 155 bp sequence and a 14 bp unrelated sequence. This structure of the repetitive element is novel. 相似文献
26.
Takashi Tsuchiya Atsushi Ichimura Yoshinori Nagai 《Cell biochemistry and biophysics》1987,11(1):109-122
Correlations in the baker map and the tent map as examples of one-dimensional, fully developed chaos are considered. It is
shown, utilizing symbolic dynamical systems derived from these maps, that the vanishing second-order correlation function
is not sufficient to guarantee uncorrelatedness. Importance of the higher-order, especially third-order, correlation functions
is emphasized for chaotic systems. In search of the quantities that grasp correlational behaviors as a whole in chaotic systems,
it is proposed to use the fixed-separation correlation integral, which is a modified quantity of the usual correlation integral
devised to calculate the fractal dimension of strange attractors, for these maps. It is shown that the new quantity contains
all the even-number orders of autocorrelation function that are commonly considered. 相似文献
27.
Mogens L. Glass Atsushi Ishimatsu Kjell Johansen 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1986,156(3):425-430
Summary The snake-head fish (Channa argus) is an obligate air-breather inhabiting fresh waters in the temperate zone of East Asia.Ventilation of the air-breathing organ and aerial gas exchange were measured in 1 to 2 kg specimens at 15 and 25°C. Additionally, the ventilatory responses to hypoxia and hypercapnia were studied. Aerial ventilation increased from 1.1 to 2.9 mlbtps·kg–1·min–1 when temperature rose from 15 to 25°C. Concomitantly, O2-uptake through airbreathing increased from 0.1 mlstpd·kg–1·min–1 (15°C) to 0.28 mlstpd·kg–1·min–1 (25°C), whereas aerial gas exchange was less important for CO2-climination as evident from low gas exchange ratios (0.16 at 15°C, 0.29 at 25°C).Ventilation increases only slightly in response to inspiration of hypercapnic gas mixtures or to hypoxic conditions in water. By contrast, inspiration of hypoxic gas mixtures caused marked increases of ventilation in particular at the higher temperature.Aerial ventilation inChanna is low compared to values for ectothermic pulmonary breathers. However, its ventilatory responses to hypoxia strikingly resemble those of reptiles: The most marked ventilatory response to hypoxia occurs at the higher temperature where the demands for O2 are greatest. 相似文献
28.
Effects of Some Growth Regulators and Benzoic Acid Derivatives on Flower Initiation and Root Elongation of Pharbitis nil, Strain Kidachi 总被引:1,自引:0,他引:1
Seedlings of Pharbitis nil, strain Kidachi, were grown undercontinuous light at 20°C in vessels containing 5,000-mlnutrient solution, 24 plants per vessel. NAA (0.0050.5µM), GA3 (0.10.5 µM), kinetin (0.55µM), benzyladenine (0.055 µM) or abscisicacid (4 µM) added to the nutrient solution induced long-dayflowering, and the flowering was always accompanied by suppressionof root elongation. 3,4-Dichlorobenzoic acid (0.0510µM) and some other benzoic acid derivatives which arehighly effective for the induction of flowering in Lemna paucicostataalso showed similar effects. Neither NAA, kinetin nor 3,4-dichlorobenzoicacid applied via the apical part of the hypocotyl could causeflowering or suppression of root elongation. Thus, the flower-inducingeffect of the above substances was presumed to be secondaryto the suppression of root elongation. Ethrel (150 µM)added to the nutrient solution suppressed root elongation, butdid not induce flowering probably because it has flower-inhibitingactivity.
1 This paper is dedicated to the memory of Dr. Joji Ashida,the first president of the Japanese Society of Plant Physiologists. (Received December 15, 1982; Accepted February 25, 1983) 相似文献
29.
Benzyladenine (BA) stimulated division but not expansion ofmesophyll cells and repressed chlorophyll accumulation in attachedyoung bean leaves. Even in the presence of fluorodeoxyuridine(FUdR) or mitomycin C which causes complete suppression of BA-inducedincrease in DNA content, BA increased RNA and protein contentsand fresh weight, but decreased chlorophyll accumulation. Moreover,BA n the presence of FUdR induced marked cell expansion. Inthe presence of a-amanitin (AM), BA did not produce any changein DNA content, fresh weight or cell size. All of the BA effectswere observed even in the presence of fluorouracil (FU) plusthymidine (TdR). AM and cycloheximide added 012 h effectively inhibitedBA-stimulated cell division but showed no effect if added at18 h. FU plus TdR added 018 h had almostno effect onthe cell number at 24 h. These results indicate that BA stimulates the mRNA synthesisnecessary for induction of cell division, and that the synthesisof cytoplasmic rRNA is not always necessary for BA-stimulatedcell division, and moreover, that BA stimulates expansion growthof cells in which DNA synthesis is suppressed. (Received August 16, 1982; Accepted March 31, 1983) 相似文献
30.
Atsushi Imai Hiroaki Hattori Masaru Takahashi Yoshinori Nozawa 《Biochemical and biophysical research communications》1983,112(2):693-700
The regulation of human platelet responses by cyclic AMP (cAMP) has been investigated by measuring thrombin-stimulated serotonin release, Ca2+ uptake and phospholipase activity. Thrombin-induced 1,2-diacylglycerol (DG) formation as a result of phospholipase C activation was inhibited by pretreatment with dibutyryl cAMP (dbcAMP) in a dose-dependent manner. Subsequent failure to produce phosphatidic acid (PA), which is converted from 1,2-DG by phosphorylation and would serve as intracellular Ca2+ ionophore, appeared to parallel the decrease in Ca2+ uptake activity. Phospholipase A2 activity, monitored by the production of [3H]lysophosphatidylcholine and [3H]lysophosphatidylethanolamine, was also suppressed by dbcAMP. These data indicate that the intracellular cAMP level may be closely associated with Ca2+ uptake and phospholipases activation. In addition, it is suggested that alteration of intracellular cAMP regulates phospholipase activation and consequently platelet responses, perhaps by controlling available Ca2+ content. 相似文献