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91.
Stimulation of de novo synthesis of δ-aminolevulinate dehydralasc of radishes grown under far-red light .
Density labelling studies of δ-aminolevulinate dehydratase (ALAD) in cotyledons of radish ( Raphanus sativus L. cv. Longue Rave Saumonée) seedlings demonstrate that far-red light stimulates de novo synthesis of ALAD and that the turn-over of this enzyme is very poor. Cycloheximide reduces considerably both the increase of ALAD activity and the incorporation of deuterium in ALAD, which indicates that ALAD synthesis depends upon cytoplasmic ribosomes. 相似文献
Density labelling studies of δ-aminolevulinate dehydratase (ALAD) in cotyledons of radish ( Raphanus sativus L. cv. Longue Rave Saumonée) seedlings demonstrate that far-red light stimulates de novo synthesis of ALAD and that the turn-over of this enzyme is very poor. Cycloheximide reduces considerably both the increase of ALAD activity and the incorporation of deuterium in ALAD, which indicates that ALAD synthesis depends upon cytoplasmic ribosomes. 相似文献
92.
93.
Summary Earlier studies found that cotton (Gossypium hirsutum L.) cotyledons contain several mRNAs which are more abundant during late embryogenesis than in mid-embryogenesis or early germination. They are here termed Late embryogenesis-abundant mRNAs, encoded by Lea loci. Complementary DNA clones for 18 such mRNA sequences, defined at a hybridization criterion of Tm-15°C, were identified in a mature embryo cDNA library by differential cDNA hybridization. At a lower hybridization criterion, some sequence homology was found within several of these cloned Lea mRNA sequences. Each Lea mRNA sequence comprises 0.04–1.3% of mature embryo poly(A)+ mRNA, a level ten-fold to several hundred-fold higher than in young embryo or 24 h seedling poly(A)+ mRNA. Of 18 Lea mRNA sequences examined in cultured young embryos, the level of at least 13 are specifically increased by exogenous abscisic acid (ABA), several to a level near that in normal mature embryos. However, the abundance of several of the sequences does not appear to be significantly modulated by ABA. The LEA polypeptides encoded by 10 Lea mRNA sequences were identified by hybrid-arrested translation. They include most of the late embryogenesis-abundant, ABA-inducible, polypeptides previously identified. Preliminary results suggest that many of the individual Lea mRNA sequences are transcribed from 1–3 genes in each of cotton's two subgenomes. 相似文献
94.
Thirty-nine isolates of Cryptococcus neoformans, nineteen serotype AD and twenty serotype BC, were assayed for susceptibility to eight antifungal agents using an in vitro agar dilution assay. Media employed were Kimmig agar and yeast nitrogen base supplemented with 10% glucose. The antifungal agents used were ketoconazole, amphotericin B, 5-fluorocytosine, nystatin, miconazole, BAY N 7133, ICI 153,066, and itraconazole. No clinically significant differences in in vitro minimum inhibitory concentrations were detected between serotypes AD and BC against any of the compounds tested. An adverse medium effect was observed in two of the assays, but the outcome of the AD/BC comparison was not affected. This is the first report in which the in vitro antifungal susceptibilities of Cryptococcus neoformans serotypes are analyzed. 相似文献
95.
Mesenchymal-epithelial conversions induced by 5-Azacytidine: Appearance of cytokeratin Endo-A messenger RNA 总被引:2,自引:0,他引:2
Alix Sémat Philippe Duprey Marc Vasseur Michel Darmon 《Differentiation; research in biological diversity》1986,31(1):61-66
When mouse-teratocarcinoma-derived fibroblasts (1246 cell line) are subjected to treatment with the inhibitor of DNA methylation, 5-Azacytidine (5 AzaC), they transiently express at 55-kilodalton intermediate-filament protein recognized by the epithelial-specific monoclonal antibody, TROMA-1, although they retain a fibroblastic morphology. However, rare clones (e.g., the 1339 cell line) that permanently express the antigen recognized by TROMA-1 can be derived from the 5 AzaC-treated 1246 population, and these clones have an epithelial phenotype. In the present study, we used cloned DNA probes to demonstrate that, in 1246 fibroblasts, 5 AzaC induces the appearance of Endo-A mRNA. High levels of Endo-A mRNA were also detected in the epithelial derivative, cell line 1339. In both cases, the capping site of the Endo-A mRNA was found to be the same as that in epithelial cells which normally express this RNA. 相似文献
96.
Decolorization of Several Polymeric Dyes by the Lignin-Degrading Basidiomycete Phanerochaete chrysosporium 总被引:28,自引:13,他引:15 下载免费PDF全文
The polymeric dyes Poly B-411, Poly R-481, and Poly Y-606 were examined as possible alternatives to the radiolabeled lignin previously used as a substrate in lignin biodegradation assays. Like lignin degradation, the decolorization of these dyes by the white rot basidiomycete Phanerochaete chrysosporium occurred during secondary metabolism, was suppressed in cultures grown in the presence of high levels of nitrogen, and was strongly dependent on the oxygen concentration in the cultures. A variety of inhibitors of lignin degradation, including thiourea, azide, and 4′-O-methylisoeugenol, also inhibited dye decolorization. A pleiotropic mutant of P. chrysosporium, 104-2, lacking phenol oxidase and ligninolytic activity was also not able to decolorize the polymeric dyes, whereas a phenotypic revertant strain, 424-2, regained this capacity. All of these results suggest that the ligninolytic degradation activity of the fungus was responsible for the decolorization of these dyes. 相似文献
97.
Hung Cao Danh Margherita Strolin Benedetti Philippe Dostert 《Journal of neurochemistry》1983,41(3):618-622
Abstract: Aldehyde dehydrogenase (ALDH) activity was measured in brains, livers, and hearts of 23–26-month-old and 3-month-old rats. A significant increase of ALDH activity was found in whole brain of old rats with both acetaldehyde (39%) and propionylaldehyde (15%) used as substrates. In different brain areas of old rats, with acetaldehyde used as substrate, a significant increase of ALDH activity was found in striatum (30–50%) and cerebral cortex (37%). However, no significant difference in ALDH activity was found in livers and hearts of young and old rats. Preliminary experiments showed a significant increase of aldehyde reductase activity (52%) with p -nitrobenzaldehyde used as substrate in whole brain of old rats compared with young rats. The present work indicates that an increase of ALDH activity in brain of old rats may be an adaptive phenomenon. 相似文献
98.
Plant Molecular Biology - DNAs complementary to the mRNAs coding for the major cotton 48 kD and 52 kD storage proteins have been cloned and used to characterize the principal cotton storage protein... 相似文献
99.
A cDNA clone containing the entire coding sequence of a mouse H-2Kd histocompatibility antigen 总被引:14,自引:4,他引:10 下载免费PDF全文
Jean-Louis Lalanne Christiane Delarbre Gabriel Gachelin Philippe Kourilsky 《Nucleic acids research》1983,11(5):1567-1577
We have isolated a cDNA clone carrying a 1560 bp long insert which contains the entire coding and 3' untranslated regions of an H-2K(d) mouse histocompatibility antigen. Its sequence and overal features are described. They point to the existence of unique properties of DNA sequences associated with the H-2K(d) antigen. 相似文献
100.