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1.
Alba Marina Cotes Philippe Lepoivre Jean Semal 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(5):497-506
An experimental protocol consisting in the colonisation of pregerminated bean seeds dressed withTrichoderma sp. was used in order to study the mechanisms correlated with the protective effect againstPythium splendens. Seed dressed with TH-11 (T. koningii) for 24 h presented a higher protective effect and a higher level of seed colonisation as compared to those dressed with TH-13 (T. longibranchiatum). The levels of seed coat colonisation by TH-11 and TH-13 was shown to be correlated with the carboxymethylcellulase activity, as measured in the seed coats retreived from germinating dressed bean seeds. The seed coat colonisation was also associated with an increased activities of endo-1,3--glucanase and endochitinase measured in seed extracts, and an inhibitory effect of seed extracts onPythium sporangia germination. Pretreatment of TH-13-dressed seeds with a commercial cellulase improved all parameters mentioned above, thus suggesting a role of cellulase activity in the colonisation process and the linked protective effect. The possible role of hydrolytic enzymes in the protective effects is discussed. 相似文献
2.
天然橡胶是重要的工业原材料,主要来自橡胶树树皮中的乳管。乙烯能促进橡胶树乳管产胶和排胶,在树皮上施用乙烯利(一种乙烯释放剂)或乙烯可显著提高胶乳产量。基于本课题组前期获得的橡胶树基因组和转录组数据,克隆橡胶树中乙烯合成通路关键酶——1-氨基环丙烷基-1-羧酸(ACC)氧化酶基因家族(HbACOs)的全部8个家族基因,研究其组织表达模式。结果表明:在分析的7种组织中,尽管HbACO基因存在不同程度的冗余表达,但每种基因的组织表达模式具有明显的特异性,其中HbACO7是树皮中表达量最高的家族基因。HbACO7基因的表达在割胶季节的不同月份发生明显变化,其中在8月的表达量最高。成功构建了HbACO7基因的原核表达载体,实现其在大肠杆菌BL21中的诱导表达。纯化后的HbACO7重组蛋白具有明显的ACO酶催化活性,成功地催化了乙烯的体外合成。该结果将为后续橡胶树树皮中的乙烯生物合成调控机制研究提供参考。 相似文献
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AIM: To investigate the effect of SIRT1 on the autophagy of pancreatic cancer cells under hypoxia condition, and to analyze the underlying mechanism of regulating FOXO1/RAB7 signaling pathway. METHODS: Western blot and immunofluorescence methods were used to determine the expression of SIRT1 in the pancreatic cancer cells. The small interfering RNA targeting SIRT1 and SIRT1 over-expression plasmid were transfected into the pancreatic cancer Panc-1 cells. Confocal microscopy was used to detect the LC3 expression. Western blot was used to analyze the protein levels of LC3, p62 and FOXO1/RAB7 signaling pathway-related molecules. Co-immunoprecipitation was used to detected the protein interaction between SIRT1 and FOXO1. RESULTS: The expression level of SIRT1 in the nucleus of Panc-1 cells was increased under hypoxia condition. Compared with negative control under hypoxia condition, knock-down of SIRT1 expression attenuated the autophagy flux in the pancreatic cancer Panc-1 cells (P<0.05). Over-expression of SIRT1 increased the protein levels of FOXO1 and RAB7. On the contrary, knock-down of SIRT1 expression inhibited the protein levels of FOXO1 and RAB7. The protein interaction between SIRT1 and FOXO1 in the pancreatic cancer cells was observed. CONCLUSION: SIRT1 in pancreatic cancer Panc-1 cells under hypoxia condition is over-expressed in the nucleus. Down-regulation of SIRT1 inhibits autophagy and its mechanism may be related to FOXO1/RAB7 signaling pathway. 相似文献
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为了给河北地区预防和控制猪繁殖与呼吸综合征提供理论数据。应用RT-PCR方法特异性扩增HB-3(cz)株的ORF7(N)基因片段,将扩增片段克隆入pMD-T载体后测序,应用DNAstar分析软件对序列进行分析,并与GenBank中发表的PRRSV毒株序列进行比较。结果显示:HB-3(cz)株与高热病毒株JXA1、HUB2等及传统河北分离株HB-1(sh)氨基酸同源性高达97.6%,属美洲型毒株。将目的片段克隆入原核表达载体pGEX-6P-1,重组质粒pGEX-N转化大肠杆菌BL21(DE3),在IPTG诱导下成功获得表达,经Western-blot-ting分析表明:表达的融合蛋白分子量约为39.5 kDa,能与PRRSV的阳性血清发生特异性反应,为PRRSV血清学诊断方法的建立奠定了基础。 相似文献
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以大豆分离蛋白为原料提取7S球蛋白,研究了风味复合蛋白酶对大豆7S球蛋白的改性作用,并且评价了7S球蛋白改性前后的功能性质。结果表明,试验得到的7S球蛋白的持水性、乳化能力和吸油性优于大豆分离蛋白。风味复合蛋白酶酶解最佳的条件为pH值8.5,温度55℃。7S球蛋白改性后功能性质优于改性前。改性后7S球蛋白持水性有明显改善,在水解度为18.43%效果最好。吸油性、乳化性及乳化稳定性也有明显改善,在16.07%的水解度时效果最好。 相似文献
8.
Effects of dietary lipids on body composition and liver function in juvenile red drum, Sciaenops ocellatus 总被引:2,自引:0,他引:2
This study was conducted to evaluate the effects of different concentrations of dietary lipids on body composition and liver function in juvenile red drum, Sciaenops ocellatus. Diets were formulated to contain 40% crude protein from solvent-extracted menhaden fish meal and 0, 7, 14 or 21% lipid from menhaden fish oil. The basal diet, without supplemental fish oil, contained lipid at 0.4% of dry weight. The diets were fed to groups of 25 juvenile red drum initially averaging 7.3 ± 0.18 g fish–1 in a recirculating culture system for 8 weeks and weight gain was recorded. After an additional 8 weeks, 16 fish from each treatment were sacrificed and the following measurements were recorded: hepatosomatic index (HSI), intraperitoneal fat (IPF) ratio, and liver -tocopherol, malondialdehyde (MDA) formation, and cytochrome P-4501A activity (measured as 7-ethoxyresorufin O-deethylase (EROD) activity). The activity of alanine and aspartate aminotransferases and concentrations of -tocopherol also were measured in plasma.Weight gain was significantly (p<0.05) affected by dietary lipid concentration, with values ranging from 361% of initial weight for fish fed the basal diet to 527% of initial weight for fish fed the diet containing 7% lipid. The HSI and IPF ratio values also were significantly affected by lipid with the lowest values recorded for fish fed the basal diet and the highest values observed in fish fed the diet containing 21% lipid. Increasing dietary lipid significantly increased oxidative stress as reflected in reduced -tocopherol in liver and plasma and increased MDA formation in the liver, although no overt pathological signs were observed. These findings suggest that lipid concentrations between 7 and 14%, when the diet contains 60 IU vitamin E kg–1, are likely to limit oxidative stress and result in normal physiological responses of red drum. 相似文献
9.
【目的】了解let-7a-5p的生物学信息,初步探索其在静原鸡肌肉组织中的功能作用。【方法】利用生物信息学方法对转录组测序获得的静原鸡let-7a-5p的成熟序列进行保守性分析,使用miRDB、TargetScan和miRanda在线软件预测let-7a-5p的靶基因,取其交集进行GO功能和KEGG通路富集分析,并利用实时荧光定量PCR检测let-7a-5p在静原鸡公鸡和母鸡各组织中的表达水平。【结果】let-7a-5p的成熟序列在各物种间高度保守,共预测得到38个基因集合。在生物过程、细胞组分和分子功能中靶基因富集较多的GO条目有细胞过程、生物调节、细胞、结合和催化活性;靶基因显著富集于聚酮糖单元生物合成、AGE-RAGE信号通路在糖尿病并发症中的作用、泛素介导的蛋白水解、TGF-β信号通路和加压素调节的水重吸收信号通路,且富集最多的是代谢途径、AGE-RAGE信号通路在糖尿病并发症中的作用、泛素介导的蛋白水解和MAPK信号通路。let-7a-5p-靶基因互作主要通过作用于靶mRNA的3′-UTR抑制表达或使其降解。组织表达发现,let-7a-5p在静原鸡公、母鸡的心脏、肝脏、脾脏、... 相似文献
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