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21.
Arabidopsis CUP-SHAPED COTYLEDON3 regulates postembryonic shoot meristem and organ boundary formation 总被引:1,自引:0,他引:1 下载免费PDF全文
Overall shoot architecture in higher plants is highly dependent on the activity of embryonic and axillary shoot meristems, which are produced from the basal adaxial boundaries of cotyledons and leaves, respectively. In Arabidopsis thaliana, redundant functions of the CUP-SHAPED COTYLEDON genes CUC1, CUC2, and CUC3 regulate embryonic shoot meristem formation and cotyledon boundary specification. Their functional importance and relationship in postembryonic development, however, is poorly understood. Here, we performed extensive analyses of the embryonic and postembryonic functions of the three CUC genes using multiple combinations of newly isolated mutant alleles. We found significant roles of CUC2 and CUC3, but not CUC1, in axillary meristem formation and boundary specification of various postembryonic shoot organs, such as leaves, stems, and pedicels. In embryogenesis, all three genes make significant contributions, although CUC3 appears to possess, at least partially, a distinct function from that of CUC1 and CUC2. The function of CUC3 and CUC2 overlaps that of LATERAL SUPPRESSOR, which was previously shown to be required for axillary meristem formation. Our results reveal that redundant but partially distinct functions of CUC1, CUC2, and CUC3 are responsible for shoot organ boundary and meristem formation throughout the life cycle in Arabidopsis. 相似文献
22.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
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Mizuho Kusuda Mitsuhiro Ueda Yasuhito Konishi Yoshihito Araki Katsuji Yamanaka Masami Nakazawa Kazutaka Miyatake Takao Terashita 《Mycoscience》2006,47(4):184-189
We investigated extracellular carbohydrase production in the medium of an ectomycorrhizal fungus, Tricholoma matsutake, to reveal its ability to utilize carbohydrates such as starch as a growth substrate and to survey the saprotrophic aspects.
We found β-glucosidase activity in the static culture filtrate of this fungus. The β-glucosidase was purified and characterized.
The purified enzyme was obtained from about 2.1 l static culture filtrate, with 9.0% recovery, and showed a single protein
band on SDS-PAGE. Molecular mass was about 160 kDa. The enzyme was most active around 60°C and pH 5.0, and stable over a pH
of 4.0–8.0 for 30 min at 37°C. The purified enzyme was activated by the presence of Ca2+ and Mn2+ ions (about 2–3 times that of the control). The enzyme readily hydrolyzed oligosaccharides having a β-1,4-glucosidic linkage
such as cellobiose and cellotriose. However, it did not hydrolyze polysaccharides such as avicel and CM-cellulose or oligosaccharides
having an α-glucosidic linkage. Moreover, cellotriose was hydrolyzed by the enzyme for various durations, and the resultant
products were analyzed by TLC. We concluded that the enzyme from T. matsutake seems to be a β-glucosidase because cellotriose with a β-1,4-glucosidic linkage decomposed to glucose during the enzyme reaction. 相似文献
24.
Aida M Beis D Heidstra R Willemsen V Blilou I Galinha C Nussaume L Noh YS Amasino R Scheres B 《Cell》2004,119(1):109-120
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A total of 45 juvenile [30.0–57.4 mm total length (TL)] slime flounder Microstomus achne were collected in the coastal area of southern Hokkaido from April to July in 2001 and April to June in 2002. Their diets
were analyzed. Slime flounder juveniles of 30.0–39.9 mm TL fed predominantly on small crustaceans (gammarid amphipods, harpacticoids
and cumaceans) and those of 40.0–57.4 mm TL on gammarid amphipods, cumaceans and polychaetes. The major prey items changed
with growth from small crustaceans (e.g., harpacticoids) to polychaetes, although gammarid amphipods were the major prey items
throughout the juvenile period (30.0–57.4 mm TL). 相似文献
28.
Shiroma R Park JY Al-Haq MI Arakane M Ike M Tokuyasu K 《Bioresource technology》2011,102(3):2943-2949
We improved the CaCCO process for rice straw by its incorporation with a step of lime pretreatment at room temperature (RT). We firstly optimized the RT-lime pretreatment for the lignocellulosic part. When the ratio of lime/dry-biomass was 0.2 (w/w), the RT lime-pretreatment for 7-d resulted in an effect on the enzymatic saccharification of cellulose and xylan equivalent to that of the pretreatment at 120°C for 1h. Sucrose, starch and β-1,3-1,4-glucan, which could be often detected in rice straw, were mostly stable under the RT-lime pretreatment condition. Then, the pretreatment condition in the conventional CaCCO process was modified by the adaptation of the optimized RT lime-pretreatment, resulting in significantly better carbohydrate recoveries via enzymatic saccharification than those of the CaCCO process (120°C for 1 h). Thus, the improved CaCCO process (the RT-CaCCO process) could preserve/pretreat the feedstock at RT in a wet form with minimum loss of carbohydrates. 相似文献
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30.
Quantitative and antioxidative behavior of Trolox in rats’ blood and brain by HPLC‐UV and SMFIA‐CL methods 下载免费PDF全文
Mitsuhiro Wada Misato Wada Rie Ikeda Yuki Fuchigami Hironari Koyama Susumu Ohkawara Shigeru Kawakami Naotaka Kuroda Kenichiro Nakashima 《Luminescence》2016,31(2):414-418
Trolox, a water‐soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi‐microflow injection analysis, chemiluminescence detection and HPLC‐UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored. The antioxidative effects in blood (12.0 ± 2.1) and brain (8.4 ± 2.1, × 103 antioxidative effect % × min) also increased. Additionally, the areas under the curve (AUC)s0–360 (n = 3) for blood and brain calculated with quantitative data were 10.5 ± 1.2 and 9.7 ± 2.5 mg/mL × min, respectively. This result indicates that Trolox transferability through the blood–brain barrier is high. The increase in the antioxidative effects caused by Trolox in the blood and brain could be confirmed because good correlations between concentration and antioxidative effects (r ≥ 0.702) were obtained. The fact that Trolox can produce an antioxidative effect in rat brain was clarified. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献