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411.
Pin Guo Jin Lan Jianwei Ge Quanmin Nie Liemei Guo Yongming Qiu Qing Mao 《Experimental cell research》2014
Glioblastoma multiforme (GBM) is notoriously resistant to radiation, and consequently, new radiosensitizers are urgently needed. MicroRNAs are a class of endogenous gene modulators with emerging roles in DNA repair. We found that overexpression of miR-26a can enhance radiosensitivity and reduce the DNA repair ability of U87 cells. However, knockdown miR-26a in U87 cells could act the converse manner. Mechanistically, this effect is mediated by direct targeting of miR-26a to the 3′UTR of ATM, which leads to reduced ATM levels and consequent inhibition of the homologous recombination repair pathway. These results suggest that miR-26a may act as a new radiosensitizer of GBM. 相似文献
412.
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414.
Nan Zhang Zhentai Han Guiling Sun Angela Hoffman Iain W. Wilson Yanfang Yang Qian Gao Jianqiang Wu Dan Xie Jungui Dai Deyou Qiu 《Biochemical and biophysical research communications》2014
Taxol is a well-known effective anticancer compound. Due to the inability to synthesize sufficient quantities of taxol to satisfy commercial demand, a biotechnological approach for a large-scale cell or cell-free system for its production is highly desirable. Several important genes in taxol biosynthesis are currently still unknown and have been shown to be difficult to isolate directly from Taxus, including the gene encoding taxoid 9α-hydroxylase. Ginkgo biloba suspension cells exhibit taxoid hydroxylation activity and provides an alternate means of identifying genes encoding enzymes with taxoid 9α-hydroxylation activity. Through analysis of high throughput RNA sequencing data from G. biloba, we identified two candidate genes with high similarity to Taxus CYP450s. Using in vitro cell-free protein synthesis assays and LC–MS analysis, we show that one candidate that belongs to the CYP716B, a subfamily whose biochemical functions have not been previously studied, possessed 9α-hydroxylation activity. This work will aid future identification of the taxoid 9α-hydroxylase gene from Taxus sp. 相似文献
415.
Y. C. Qi W. Q. Liu L. Y. Qiu S. M. Zhang L. Ma H. Zhang 《Russian Journal of Plant Physiology》2010,57(2):233-240
The Suaeda salsa glutathione S-transferase gene (GST) was introduced into arabidopsis under the control of the cauliflower mosaic virus 35S
promoter. Transformants were selected for their ability to grow on medium containing kanamycin. Southern and northern blot
analyses confirmed that GST was transferred into the arabidopsis genome, and the GST and GPX activities in transgenic plants
(GT) were much higher than in wild-type plants (WT). There were no obvious morphological or developmental differences between
transgenic and wild-type plants. One transgenic homozygous line (GT6–8) and WT plants were evaluated for salt tolerance and gene expression. Seed germination and seedling salt tolerance were improved
after overexpression of GST in arabidopsis; the photosynthesis rate and the fresh weight of the GT6–8 line were distinctly higher than those of WT plants after NaCl treatment. Glutathione content increased substantially in
salt-stressed arabidopsis plants of both genotypes, and the glutathione pool in GT6–8 plants was more oxidized than in WT plants under both control and stressful conditions. The MDA content, an indicator of
lipid peroxidation, increased in WT plants but was not affected distinctly in GT6–8 seedlings after NaCl treatment. Results from different tests indicated that the expression of the GST gene promoted a higher
level of salt tolerance in vivo in transgenic arabidopsis plants. 相似文献
416.
Xiuli Wang Xiangying Meng Bin Song Xuemei Qiu Haiying Liu 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(3):327-330
Myostatin (MSTN) is a member of the transforming growth factor-β superfamily which negatively regulates growth of muscle tissue. In this study, 103 cultivated Chlamys farreri individuals were screened for polymorphisms in the MSTN gene using PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods. Two mutations were found: A/G at position 327 in exon 2, which caused an amino acid change from Thr to Ala (Thr305Ala), and C/T at position 289 in exon 3, which caused an amino acid change from Cys to Arg (Cys422Arg). One way ANOVA of the SNPs and growth traits showed that genotype GG of primer M5 had significantly higher body mass, soft-tissue mass, adductor muscle mass, shell length, shell height, absolute growth rate of shell height and body mass than those of genotype AG and AA (P < 0.05). Genotype frequencies of genotype AA, AG and GG were 68.94%, 27.18% and 3.88%, respectively. The results present evidence that the C. farreri MSTN gene may be selected as a candidate gene for these growth traits. 相似文献
417.
Laccase, a so-called “blue-copper” oxidase, is able to oxidize a variety of organic compounds. Sol–gel derived silica glasses
are frequently adopted as an immobilization method to improve the stability of enzymes and make them reusable. In this study,
immobilization conditions were optimized to achieve improved embedding results. The thermal stability, reaction stability
and storage stability were improved with the immobilized enzyme when compared to the free enzyme. 2,4-Dichlorophenol (DCP)
and 2,4,6-trichlorophenol (TCP) were chosen as model compounds. The treatment of chlorophenols (CPs) by immobilized laccase
demonstrated excellent removal and response stability. The affinity of TCP for immobilized laccase was higher than that of
DCP. This finding leads to different removal efficiencies under variable conditions (reaction time, initial concentration,
dosage of immobilized laccase and removal rate in mixed solution). By fitting the experimental data with the diffusion model
of the degradation process, the degradation of CPs by immobilized laccase matches an intraparticle diffusion-controlled model. 相似文献
418.
419.
Wei Li Yi-Min Tao Yun Tang Xue-Jun Xu Jie Chen Wei Fu Xing-Hai Wang Bo Chao Wei Sheng Qiong Xie Zhui-Bai Qiu Jing-Gen Liu 《Bioorganic & medicinal chemistry letters》2010,20(1):418-421
Unexpected substituent on the well-known morphine skeleton is described to be account for highly selective and potent μ opioid ligands, which is strongly connected to substituted aromatic groups on this omitted 8α-position. 相似文献
420.
Guozhi Tang Denis J. Kertesz Minmin Yang Xianfeng Lin Zhanguo Wang Wentao Li Zongxing Qiu Junli Chen Jianghua Mei Li Chen Taraneh Mirzadegan Seth F. Harris Armando G. Villaseñor Jennifer Fretland William L. Fitch Julie Qi Hang Gabrielle Heilek Klaus Klumpp 《Bioorganic & medicinal chemistry letters》2010,20(20):6020-6023