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Hoshino Atsushi; Abe Yukihide; Saito Norio; Inagaki Yoshishige; Iida Shigeru 《Plant & cell physiology》1997,38(8):970-974
The Japanese morning glory carrying the recessive mutable speckledallele with the dominant speckled-activator bears colorlessflowers with fine and round colored spots distributed over thecorolla whereas the plant without the speckled-activator producespale yellow flowers. Previous chemical analysis has indicatedthat a mutation in the gene for flavanone 3-hydroxylase (F3H)is a likely candidate for the speckled allele. However, theF3HmRNA without sequence alteration accumulates normally inthe pale yellow flowers, indicating that the speckled alleleis neither the F3H gene nor a regulatory gene acting on theF3H gene expression. (Received April 4, 1997; Accepted June 2, 1997) 相似文献
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Toshiyuki Hamaoka Yasuyuki Takai Atsushi Kosugi Yumiko Mizushima Junko Shima Tsuneo Kusama Hiromi Fujiwara 《Cancer immunology, immunotherapy : CII》1985,20(3):183-188
Summary A new haptenic compound, a muramyl dipeptide (MDP) derivative (designated as L4-MDP-ONB) cross-reactive with Bacillus Calmette Guerin (BCG) was synthesized. The cross-reactivity of L4-MDP hapten to BCG was demonstrated from the following evidence; (a) lymph node cells from BCG-primed C3H/HeN mice exhibited appreciable L4-MDP-specific proliferative responses to the in vitro stimulation of L4-MDP-modified syngeneic cells (L4-MDP-self); (b) inoculation of L4-MDP-self into footpads of BCG-primed C3H/HeN mice elicited ample delayed type-hypersensitivity (DTH) responses in vivo as measured by footpad swelling; and (c) BCG-primed mice contained L4-MDP-reactive helper T cell activity which functions to augment the generation of effector T cell responses to cell surface antigens. This crossreactivity between L4-MDP hapten and BCG as measured by the helper T cell activity was applied to enhanced induction of tumor-specific immunity. When BCG-primed C3H/HeN mice were immunized with L4-MDP-modified syngeneic X5563 tumor cells, these mice could generate augmented tumor-specific in vivo protective (tumor neutralizing) immunity as well as in vitro cytotoxic T cell responses. These results indicate the effectiveness of L4-MDP hapten in augmenting tumor-specific immunity. The present approach is discussed in the context of potential advantages of this new hapten for its future application to clinical tumor systems. 相似文献
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The effects of nutrient limitation and -irradiation on trachearyelement differentiation and cell division were investigatedusing single cells isolated from the mesophyll of Zinnia elegans.When the phosphate concentration of the medium was reduced to10 µM (1/50 of Fukuda and Komamine's medium, 1980a), thefrequency of cell division during 4 days of culture decreased,while the frequency of tracheary element differentiation wasunaffected. -Irradiation with a dose of 92 Gy at 36 h of culturepreferentially and thoroughly suppressed cell division withoutreducing the number of tracheary elements formed. The appearanceof secondary cell wall thickenings was delayed by irradiation,but synchrony was maintained. Thus the Zinnia system previouslyreported [Fukuda and Komamine (1980a) Plant Physiol. 65: 57]was improved to give a more useful system for the study of cytodifferentiation,in which tracheary element formation occurred from single cellswithout cell division.
1Present address: Biological Institute, Faculty of Science,Tohoku University, Sendai, Miyagi 980, Japan. (Received November 28, 1985; Accepted February 22, 1986) 相似文献
7.
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
8.
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
9.
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
10.
Hiroshi Ashihara Atsushi Komamine Masami Shimokoriyama 《Journal of plant research》1974,87(2):121-131
Changes in activities of the glycolytic and pentose phosphate (PP) pathways in glucose catabolism in various parts of the
hypocotyls obtained from 4-day-old etiolatedPhaseolus mungo seedlings were investigated by measuring the inhibition rates of respiration by iodoacetate and malonate, and the release
of14CO2 from [1-14C]- and [6-14C]glucose. The relative activity of the PP pathway in glucose catabolism was higher in the immature part (Part I) and the
aged part (Part V) of the hypocotyls than in the intermediary one (Part III), while the activity of the glycolytic pathway
decreased with aging.
On a fresh weight basis, the enzyme activities of the glycolytic and PP pathways were higher in Part I than in Parts III and
V. On a protein content basis, however, activities of the enzymes of the PP pathway increased with aging and differentiation
of the hypocotyls whereas those of the glycolytic pathway decreased. Levels of nicotinamide adenine nucleotides were found
to be in the following order: Part I>Part III> Part V for NAD++NADH; Part I>Part V>Part III for NADP++NADPH. The stimulative effect of methylene blue on decreasing the C6/C1 ratio was greater in Part III than in Part I, and No effect was observed in Part V.
These data suggest that a decrease in the activity of the glycolytic pathway with aging and differentiation may be due to
the decreasing glycolytic enzyme activities and NAD(H) content. The higher activity of the PP pathway in the immature part
is attributable to larger amounts of NADP(H) and enzymes of the PP pathway. The greater contribution of the PP pathway to
glucose catabolism in the aged part than in the intermediary part seems to results from a more active turnover of NADP and
the relatively higher activity of the enzymes of the PP pathway than those of the glycolytic pathway. 相似文献