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991.
Chao-Liang Wu Chao-Wei Chuang Hsin-Yen Cho Tzu-Hsien Chuang Sheng-Nan Wu 《International journal of molecular sciences》2022,23(7)
Mirogabalin (MGB, Tarlige®), an inhibitor of the α2δ-1 subunit of voltage-gated Ca2+ (CaV) channels, is used as a way to alleviate peripheral neuropathic pain and diabetic neuropathy. However, to what extent MGB modifies the magnitude, gating, and/or hysteresis of various types of plasmalemmal ionic currents remains largely unexplored. In pituitary tumor (GH3) cells, we found that MGB was effective at suppressing the peak (transient, INa(T)) and sustained (late, INa(L)) components of the voltage-gated Na+ current (INa) in a concentration-dependent manner, with an effective IC50 of 19.5 and 7.3 μM, respectively, while the KD value calculated on the basis of minimum reaction scheme was 8.2 μM. The recovery of INa(T) inactivation slowed in the presence of MGB, although the overall current–voltage relation of INa(T) was unaltered; however, there was a leftward shift in the inactivation curve of the current. The magnitude of the window (INa(W)) or resurgent INa (INa(R)) evoked by the respective ascending or descending ramp pulse (Vramp) was reduced during cell exposure to MGB. MGB-induced attenuation in INa(W) or INa(R) was reversed by the further addition of tefluthrin, a pyrethroid insecticide known to stimulate INa. MGB also effectively lessened the strength of voltage-dependent hysteresis of persistent INa in response to the isosceles triangular Vramp. The cumulative inhibition of INa(T), evoked by pulse train stimulation, was enhanced in its presence. Taken together, in addition to the inhibition of CaV channels, the NaV channel attenuation produced by MGB might have an impact in its analgesic effects occurring in vivo. 相似文献
992.
分子生物学技术在土壤生物修复中的应用及展望 总被引:1,自引:0,他引:1
综述了分子生物学技术包括环境微生物群落降解基因分析、16S rRNA序列分析技术以及荧光原位杂交技术在生物修复技术中跟踪污染土壤中降解微生物行为、监测降解基因和微生物群落变化,揭示了其中的分子机制的应用现状,对各项技术应用中需要注意的问题进行了讨论并对其发展前景进行了展望。 相似文献
993.
994.
995.
Eukaryotic cells react to various stress conditions with the rapid formation of membrane-less organelles called stress granules (SGs). SGs form by multivalent interactions between RNAs and RNA-binding proteins and are believed to protect stalled translation initiation complexes from stress-induced degradation. SGs contain hundreds of different mRNAs and proteins, and their assembly and disassembly are tightly controlled by post-translational modifications. The ubiquitin system, which mediates the covalent modification of target proteins with the small protein ubiquitin (‘ubiquitylation’), has been implicated in different aspects of SG metabolism, but specific functions in SG turnover have only recently emerged. Here, we summarize the evidence for the presence of ubiquitylated proteins at SGs, review the functions of different components of the ubiquitin system in SG formation and clearance, and discuss the link between perturbed SG clearance and the pathogenesis of neurodegenerative disorders. We conclude that the ubiquitin system plays an important, medically relevant role in SG biology. 相似文献
996.
一株产胞外多糖植物内生菌EJS-3菌株的分离和鉴定 总被引:9,自引:0,他引:9
从中药植物-百部的组织中分离到一株高产胞外多糖的植物内生菌EJS-3菌株,该菌株在产糖培养基中可以得到23.6g/L的胞外多糖,转化率为47.2%(gEPS/g蔗糖)。通过16SrRNA基因序列分析对该菌株进行了鉴定。通过PCR扩增,得到1450bp的16SrRNA序列。PCR产物序列通过BLAST软件在NCBI网站中进行同源性比较。通过Bioedit7.0和Treedrawing软件绘制系统发育树。结果显示,EJS-3的16SrRNA序列和数据库中的类多粘芽孢杆菌KCTC1663菌株的序列的同源性为99.31%。在细菌系统发育分类学上,EJS-3菌株归属多粘类芽孢杆菌(Paenibacilluspolymyxa)。 相似文献
997.
998.
SSR标记辅助回交转育大豆7S球蛋白α-亚基致敏蛋白缺失新品系 总被引:1,自引:0,他引:1
为快速培育7S球蛋白致敏蛋白α-亚基缺失的优质大豆新品系,以(α'+α)-亚基双缺失型材料日B为供体亲本,东农47为受体亲本,以杂交一回交转育方法为基础,结合SSR标记辅助遗传背景选择与主要农艺性状鉴定及品质分析,在BC2F4选育到7S球蛋白α-亚基缺失新品系Cb80。Cb80综合农艺性状优良,遗传背景回复率大于90%,其蛋白质及氨基酸总量为44.1%、41.95%,分别比轮回亲本东农47提高3.5和3.76个百分点。 相似文献
999.
1000.
C. Wolf M Scherzinger A. Wurz U. Pauli P. Hübner J. Lüthy 《European Food Research and Technology》2000,210(5):367-372
Today DNA-based techniques are very common for the detection of genetically modified organisms (GMOs) in food products. For
fast and easy detection of GMOs, polymerase chain reaction (PCR) screening methods, which amplify common transgenic elements,
are applied in routine analysis. These techniques do not allow differentiation between GMOs and the natural occurrence of
transgenic elements, such as the 35S-promoter of cauliflower mosaic virus (CaMV) or the NOS-terminator of Agrobacterium tumefaciens, and thus may result in false-positive detection of GMOs. In this study we evaluated three different existing 35S screening
systems and report the development of two new CaMV-specific PCR systems. These PCR systems based on CaMV-specific genes allow
the identification of positively screened 35S food samples as naturally virus-infected products or plants. Seven food samples
tested positive in routine 35S screening analysis and negative in GMO specific systems were investigated using the new virus-specific
PCR systems. In all seven samples CaMV was detected.
Received: 26 April 1999 / Revised version: 28 June 1999 相似文献