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1.
Single Cell Transcriptome Amplification with MALBAC 总被引:1,自引:0,他引:1
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ObjectiveWe investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K)/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs).MethodsCortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.ResultsMdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.ConclusionseEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent. 相似文献
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ZhiMeng Xu ChengBin Li QingLing Liu Hua Yang Ping Li 《Journal of cellular biochemistry》2019,120(10):18388-18397
Insufficient nutrients supply will greatly affect the function of cardiac myocytes. The adaptive responses of cardiac myocytes to nutritional stress are not fully known. Ginsenoside Rg1 is one of the most pharmacologically active components in Panax Ginseng and possesses protective effects on cardiomyocyte. Here, we investigate the effects of ginsenoside Rg1 on H9c2 cells which were subjected to nutritional stress. Nutritional stress-induced by glucose deprivation strongly induced cell death and this response was inhibited by ginsenoside Rg1. Importantly, glucose deprivation decreased intracellular ATP levels and mitochondrial membrane potential. Ginsenoside Rg1 rescued ATP levels and mitochondrial membrane potential in nutrient-starved cells. For molecular mechanisms, ginsenoside Rg1 increased the expressions of PTEN-induced kinase 1 (PINK1) and p-AMPK in glucose deprivation treated H9c2 cells. Reducing the expression of aldolase in H9c2 cells inhibited ginsenoside Rg1′s actions on PINK1 and p-AMPK. Further, the nutritional stress mice were used to verify the mechanisms obtained in vitro. Ginsenoside Rg1 increased the expressions of aldolase, p-AMPK, and PINK1 in starved mice heart. Taken together, our results reveal that ginsenoside Rg1 limits nutritional stress-induced H9c2 cells injury by regulating the aldolase /AMP-activated protein kinase/PINK1 pathway. 相似文献
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Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
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The use of a drug resistance cartridge for in vitro insertion and deletion mutagenesis of a cosmid clone 总被引:1,自引:0,他引:1
A drug-resistant cartridge was employed in the construction of families of insertion mutants of a cosmid clone. The cartridge contains a cml gene and has identical restriction enzyme sites, EcoRI, BamHI, SalI, and PstI, on both ends. The families of mutants were made by ligation of the cartridge to the cosmid, which was linearized or partially digested, followed by in vitro packaging and transduction. From these families we selected cosmid derivatives which either have a unique BamHI site at a predetermined site in the cosmid or have deletions covering different portions of the original clone. The extent of a large gene cluster cloned into the original cosmid was identified by confirming the gene function in some of the deletion mutants. The possibility for further and various uses of this cartridge is discussed. 相似文献
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Removal of the RecA C-terminus results in a conformational change in the RecA-DNA filament 总被引:1,自引:0,他引:1
The Escherichia coli RecA protein catalyzes homologous recombination of DNA molecules, and the active form of the protein is a helical polymer that it forms around DNA. Previous image analysis of electron micrographs has revealed the RecA protein to be organized into two domains or lobes within the RecA-DNA filament. We have now been able to show that a small modification of the RecA protein by proteolysis results in a significant shift in the internal mass in the RecA filament. We have cleaved approximately 18 residues from the C-terminus of the RecA protein, producing a roughly 36K MW RecA core protein that binds DNA and polymerizes normally. A three-dimensional reconstruction of this complex has been computed, and has been compared with a previous reconstruction of the intact protein. The main difference is consistent with a 15 A outward movement of the lobe that was at an inner radius in the wild-type protein. These observations yield additional evidence about the conformational flexibility of the RecA filament, and will aid in understanding the structural mechanics and dynamics of the RecA filament. 相似文献
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