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Hiroshi Yonemitsu Koichiro Shimomura Motoyoshi Satake Shunji Mochida Masahiko Tanaka Thoru Endo Akira Kaji 《Plant cell reports》1990,9(6):307-310
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium
Murashige and Skoog's medium
- 1/2 MS medium
one-half strength of the standard Murashige and Skoog's medium
- B5 medium
Gamborg's B5 medium
- NN medium
Nitsch and Nitsch's medium
- FW
fresh weight
- DW
dry weight 相似文献
3.
Masaki Sugiura Tsutomu Takagi Masahiko Kisumi 《Applied microbiology and biotechnology》1985,21(3-4):213-219
Summary Proline-producing strains of Serratia marcescens Sr41 were constructed by three rounds of mutagenesis. A strain SP103 which did not degrade l-proline carried the putA mutation leading to lack of proline oxidase. A 3,4-dehydroproline-resistant mutant SP105, derived from strain SP103, carried the dpr-1 mutation which resulted in desensitization of the feedback inhibition of glutamate kinase. Strain SP103 produced 5.5 mg of l-proline per ml of fermentation medium containing sucrose and urea. Growth inhibition by proline analogs was enhanced when succinate was used as a carbon source in the medium. A thiazolidine-4-carboxylate-resistant mutant SP126 derived from strain SP105 produced 20.5 mg of l-proline per ml of medium. The mutation carried by strain SP126 might be distant from dpr-1 and putA mutations on the chromosome. Pyrroline-5-carboxylate reductase was not repressed by proline in S. marcescens Sr41. 相似文献
4.
A population of a viperid snake,Trimeresurus flavoviridis, was studied over 10 years by removal trapping on a small subtropical island in Japan. The sex ratio of trapped individuals changed seasonally, but was not biased to either sex in the whole sample of 258 individuals. The age of each individual was estimated through the size structure and the age-size relationship. The minimum number of individuals at the beginning of the study was estimated through accumulating older individuals trapped in the subsequent years. By assuming an annual natural survival rate in the course of this accumulation, an age structure was simulated which led to calculate a resulted natural survival rate. The assumed rate of 0.62 fitted best to the resulted one. The annual trapped proportion estimated on the simulated absolute number of individuals was higher in older individuals than in younger ones with the overall mean of 16%. 相似文献
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Presomite stage rat embryos were cultured for 45–49 hr with medium containing various adrenergic agonists and antagonists.
-Norepinephrine but not
-norepinephrine (several orders of magnitude less potent than the
-isomer at α-1 adrenergic receptors) resulted in a dose-dependent increase of situs inversus similar to that found for phenylephrine, an α-1 adrenergic agonist. Prazosin, an α-1 adrenergic antagonist, inhibited phenylephrine-induced situs inversus in a dose-dependent manner. Neither dexmedetomidine, an α-2 adrenergic agonist, nor isoproterenol, a β adrenergic agonist, caused situs inversus. These results provide pharmacological evidence that stimulation of α-1 but not of α-2 and β adrenergic receptors modulates the control of left/right sidedness in rat embryos. 相似文献
8.
Saito Masahiko; Kondo Noriaki; Yamaguchi Hisao; Hashimoto Tohru 《Plant & cell physiology》1976,17(3):411-416
Nine bibenzyls and 10 stilbenes were synthesized as analoguesof batatasin III, a growth inhibitor isolated from dormant yambulbils, and examined for their plant growth-regulating activities.The bioassays used were the elongation of dark-grown intactrice coleoptiles, auxin-induced elongation of excised oat coleoptiles,and germination of rape and barnyard grass seeds. In the elongationof intact rice coleoptiles, 3,3'-dihydroxy-5-methoxy- (batatasinIII), 3,5-dimethoxy-3'-nitro-, 4'-bromo-3-nitro-, 3-amino-3'-chloro-,3-amino-4'-chloro-bibenzyls and 3-benzyloxy-4'-bromo-5-methoxy-,3-benzyloxy-3',4'-dichloro-5-methoxy-stilbenes were inhibitory,and 4'-bromo-3-nitrostilbene was promotive at a concentrationof 100 mg/liter. The results obtained by the other bioassayswere qualitatively consistent with these findings, although3-amino-4'- chlorobibenzyl and 4'-bromo-3-nitrostilbene werenot tested in all the bioassays. In the seed germination, which was rather tolerant to the testanalogues, batatasin III was inactive but 3-benzyloxy-4'-bromo-5-methoxy-and 3-benzyloxy-3',4'-dichloro- 5-methoxystilbenes were veryactive. Thus, if substituted properly, bibenzyls and stilbenes are activewithout hydroxyl and methoxyl group(s) as the functional group.
3 Present address: The National Institute for EnvironmentalStudies, Yatabc, Ibaraki 300-21, Japan. (Received November 19, 1975; ) 相似文献
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Daichi Toyoda Atsuhiro Taguchi Masahiko Chiga Tomoko Ohmori Ryuichi Nishinakamura 《PloS one》2013,8(6)
The kidney, the metanephros, is formed by reciprocal interactions between the metanephric mesenchyme and the ureteric bud, the latter of which is derived from the Wolffian duct that elongates in the rostral-to-caudal direction. Sall1 expressed in the metanephric mesenchyme is essential for ureteric bud attraction in kidney development. Sall4, another member of the Sall gene family, is required for maintenance of embryonic stem cells and establishment of induced pluripotent stem cells, and is thus considered to be one of the stemness genes. Sall4 is also a causative gene for Okihiro syndrome and is essential for the formation of many organs in both humans and mice. However, its expression and role in kidney development remain unknown, despite the essential role of Sall1 in the metanephric mesenchyme. Here, we report that mouse Sall4 is expressed transiently in the Wolffian duct-derived lineage, and is nearly complementary to Sall1 expression. While Sall4 expression is excluded from the Wolffian duct at embryonic (E) day 9.5, Sall4 is expressed in the Wolffian duct weakly in the mesonephric region at E10.5 and more abundantly in the caudal metanephric region where ureteric budding occurs. Sall4 expression is highest at E11.5 in the Wolffian duct and ureteric bud, but disappears by E13.5. We further demonstrate that Sall4 deletion in the Wolffian duct and ureteric bud does not cause any apparent kidney phenotypes. Therefore, Sall4 is expressed transiently in the caudal Wolffian duct and the ureteric bud, but is dispensable for kidney development in mice. 相似文献