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排序方式: 共有201条查询结果,搜索用时 15 毫秒
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93.
红曲菌能产生多种有益的次级代谢产物,但红曲菌也产生一种对人和哺乳动物肝和肾有毒害的毒素,即桔霉素。因此控制毒素的产生是保障红曲产品安全性所必须的。故对桔霉素的合成途径及相关的基因做深入了解。6个桔霉素合成相关的基因成簇位于21 kb的DNA片段上。克隆了一个新基因(orf7基因),其位于该基因簇的外侧。采用基因敲除技术,构建红曲菌orf7基因缺失菌株。并采用紫外分光光度法检测orf7基因缺失菌株的红曲色素产量,HPLC法检测其桔霉素产量。orf7缺失菌株产红曲色素能力与出发菌株As3.4384相比没有变化;产桔霉素培养13~19 d,桔霉素的产量与出发菌株As3.4384相比增加了 142.4%。从而证实orf7基因与桔霉素代谢相关。 相似文献
94.
Xu Zhou Ying‐Hua Qiu Pei He Fei Jiang Long‐Fei Wu Xin Lu Shu‐Feng Lei Fei‐Yan Deng 《Journal of cellular and molecular medicine》2019,23(2):898-907
A large number of SNPs significant for osteoporosis (OP) had been identified by genome‐wide association studies. However, the underlying association mechanisms were largely unknown. From the perspective of protein phosphorylation, gene expression regulation, and bone cell activity, this study aims to illustrate association mechanisms for representative SNPs of interest. We utilized public databases and bioinformatics tool to identify OP‐associated SNPs which potentially influence protein phosphorylation (phosSNPs). Associations with hip/spine BMD, as well as fracture risk, in human populations for one significant phosSNP, that is, rs227584 (major/minor allele: C/A, EAS population) located in C17orf53 gene, were suggested in prior meta‐analyses. Specifically, carriers of allele C had significant higher BMD and lower risk of low‐trauma fractures than carriers of A. We pursued to test the molecular and cellular functions of rs227584 in bone through osteoblastic cell culture and multiple assays. We identified five phosSNPs significant for OP (P < 0.01). The osteoblastic cells, which was transfected with wild‐type C17orf53 (allele C at rs227584, P126), demonstrated specific interaction with NEK2 kinase, increased expression levels of osteoblastic genes significantly (OPN, OCN, COL1A1, P < 0.05), and promoted osteoblast growth and ALP activity, in contrast to those transfected with mutant C17orf53 (allele A at rs227584, T126). In the light of the consistent evidences between the present functional study in human bone cells and the prior association studies in human populations, we conclude that the SNP rs227584, via altering protein‐kinase interaction, regulates osteoblastic gene expression, influences osteoblast growth and activity, hence to affect BMD and fracture risk in humans. 相似文献
95.
Heidrun Vogt 《当今生物学》2020,50(4):254-262
The invasive Spotted Wing Drosophila – a significant pest The Spotted Wing Drosophila (Drosophila suzukii), native in South-East Asia, is an invasive pest belonging to the small fruit fly family of Drosophilidae, also named vinegar flies. Apparently displaced by global trade to the USA and Europe, this pest was able to disperse enormously over the continents since 2008. Ideal preconditions for this spread were suitable climatic conditions, the availability of a wide variety of host plants and the use of an ecological niche, namely healthy ripening and ripe fruits. In addition, D. suzukii is highly reproductive and owns excellent overwintering strategies. The Spotted Wing Drosophila is difficult to control and causes enormous damage. 相似文献
96.
Weiming Luo David Tweedie Shaunna L. Beedie Neil Vargesson William D. Figg Nigel H. Greig Michael T. Scerba 《Bioorganic & medicinal chemistry》2018,26(8):1547-1559
A library of 15 novel and heretofore uncharacterized adamantyl and noradamantyl phthalimidines was synthesized and evaluated for neuroprotective and anti-angiogenic properties. Phthalimidine treatment in LPS-challenged cells effected reductions in levels of secreted TNF-α and nitrite relative to basal amounts. The primary SAR suggests nitration of adamantyl phthalimidines has marginal effect on TNF-α activity but promotes anti-nitrite activity; thioamide congeners retain anti-nitrite activity but are less effective reducing TNF-α. Site-specific nitration and thioamidation provided phthalimidine 24, effecting an 88.5% drop in nitrite concurrent with only a 4% drop in TNF-α. Notable anti-angiogenesis activity was observed for 20, 21 and 22. 相似文献
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98.
Cytoplasmic male sterility (CMS) in plants is known to be associated with novel open reading frames (ORFs) that result from
recombination events in the mitochondrial genome. In this study Southern and Northern blot analyses using several mitochondrial
DNA probes were conducted to detect the presence of differing band patterns between male fertile and CMS lines of chili pepper
(Capsicum annuum L.). In the CMS pepper, a novel ORF, termed orf456, was found at the 3′-end of the coxII gene. Western blot analysis revealed the expression of an approximately 17-kDa product in the CMS line, and the intensity
of expression of this protein was severely reduced in the restorer pepper line. To investigate the functional role of the
ORF456 protein in plant mitochondria, we carried out two independent experiments to transform Arabidopsis with a mitochondrion-targeted orf456 gene construct by Agrobacterium-mediated transformation. About 45% of the T1 transgenic population showed the male-sterile phenotype and no seed set. Pollen grains from semi-sterile T1 plants were observed to have defects on the exine layer and vacuolated pollen phenotypes. It is concluded that this newly
discovered orf456 may represent a strong candidate gene – from among the many CMS-associated mitochondrial genes – for determining the male-sterile
phenotype of CMS in chili pepper.
GenBank accession number DQ116040 (orf456 genomic sequence), DQ126683 (pepper coxII genomic sequence) 相似文献
99.
Callicarpenal (13, 14, 15, 16-tetranor-3-cleroden-12-al) and intermedeol [(4S,5S,7R,10S)-eudesm-11-en-4-ol], isolated from American beautyberry, Callicarpa americana (Lamiaceae), were evaluated in laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged
tick, Ixodes scapularis, and lone star tick, Amblyomma americanum. A strip of organdy cloth treated with test solution was doubly wrapped (treatment on outer layer) around the middle phalanx
of a forefinger and ticks released on the fingertip. Callicarpenal and intermedeol, at 155 nmole/cm2 cloth repelled 98 and 96% of I. scapularis nymphs, respectively. Dose response tests with I. scapularis nymphs showed no difference in repellency among callicarpenal, intermedeol and Deet (N,N-diethyl-3-methylbenzamide), however, SS220 ((1S,2′S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide) was significantly more repellent than the other compounds. Callicarpenal,
at 155 nmole/cm2 cloth, repelled 100 and 53.3% of I. scapularis nymphs at 3 and 4 h, respectively, after the cloth was treated, whereas intermedeol repelled 72.5% of I. scapularis nymphs 3 h after treatment. In comparison with the results obtained with I. scapularis, callicarpenal, intermedeol, Deet and SS220 were less effective against A. americanum. Only intermedeol and SS220 repelled significantly more A. americanum than ethanol controls at 155 nmole compound/cm2 cloth. At 1,240 nmole/cm2 cloth, callicarpenal and intermedeol repelled 20 and 40% of A. americanum nymphs. 相似文献
100.
Rachidi M Lopes C Vayssettes C Smith DJ Rubin EM Delabar JM 《Biochemical and biophysical research communications》2007,364(3):488-494
Down syndrome (DS) is the most frequent genetic cause of mental retardation (MR) associated with neurological alterations. To allow a genetic dissection of DS phenotype, we studied eight transgenic mouse lines carrying YACs containing human DNA fragments covering DS critical region (DCR-1), as an in vivo library. Herein, we found an increased brain size in the 152F7-mice containing DYRK1A gene. We also identified a new cerebellar alteration in two independent lines carrying 230E8-YAC. These mice showed significant elongation of the cerebellar antero-posterior axis (p < 0.001), determined by increased length of rostral folia of the vermis (lobule II-V, p < 0.0001; lobule VI, p < 0.001). In addition, we identified a major neurological defect in culmen and declivus lobules in the 230E8-mice. We analyzed P30, P12, and P9 stages and detected high significant increased lengths of anterior lobules (II-VI) of 230E8-mice at P30 and P12 (lobule II-V, p < 0.0001; lobule VI, p < 0.05), but not at P9, indicating that this new phenotype appears between P9 and P12. Interestingly, 230E8-mice also present increased cortical cell density and mild learning defects. 230E8-YAC contains seven genes, some of which could be potentially responsible for this phenotype. Between them, we proposed DOPEY2 as potential candidate gene for these cerebellar alterations considering its high expression in the brain and that its homologous genes in yeast, Caenorhabditis elegans and Drosophila are involved in morphogenesis, suggesting a conserved role of DOPEY2 as a patterning gene. 相似文献