Dual labeling of an RNA can provide Förster resonance energy transfer(FRET)sensors for studying RNA folding,miRNA maturation,and RNA-protein interactions.Here,we report the development of a highly efficient strat...Dual labeling of an RNA can provide Förster resonance energy transfer(FRET)sensors for studying RNA folding,miRNA maturation,and RNA-protein interactions.Here,we report the development of a highly efficient strategy for direct dual-terminal labeling of any RNA of interest.We explored new Michael cycloaddition for facile labeling of 5′-terminal RNA with improved efficiency.Direct chemical tetrazinylation of RNA at the 3′-terminus was achieved with the highly efficient and catalysis-free tetrazine-cycloalkyne ligation.Both single-terminal labeling methods were combined for dual-terminal labeling of an RNA including short hairpin RNA,pre-miRNA,riboswitch,and noncoding RNA.Notably,these dual-labeled RNA-based FRET sensors were used to monitor RNA-ligand interactions in vitro and in live cells.It is anticipated that these universal RNA labeling strategies will be useful to study RNA structures and functions.展开更多
目的 :探讨大肠癌细胞 Fas配体 (Fas L ) m RNA和蛋白的表达及其功能。方法 :分别采用 RT- PCR和 Western印迹法以及氚释放细胞活性测定技术检测大肠癌细胞株中 Fas L m RNA和蛋白的表达及其功能。结果 :所检测的 6株大肠癌细胞(RPMI 4...目的 :探讨大肠癌细胞 Fas配体 (Fas L ) m RNA和蛋白的表达及其功能。方法 :分别采用 RT- PCR和 Western印迹法以及氚释放细胞活性测定技术检测大肠癌细胞株中 Fas L m RNA和蛋白的表达及其功能。结果 :所检测的 6株大肠癌细胞(RPMI 4788、HCT- 116、DL D- 1、L o Vo、Wi Dr和 COL O 32 0 DM)全部表达 Fas L m RNA和蛋白 ;DL D- 1,L o Vo和 Wi Dr等部分大肠癌细胞具有 Fas依赖的细胞毒活性。其中 DL D- 1细胞活性具有量效关系 ,并且乙酸肉豆蔻佛波醇 (PMA )和离子霉素(ionom ycine )刺激能显著增强 DL D- 1的细胞活性。结论 :DL D- 1、L o Vo和 Wi Dr等 3株大肠癌细胞表达功能性 Fas配体 ,并可能以此反击机体免疫系统 ,逃避免疫监督。展开更多
目的:观察用RNA干扰的方法抑制大鼠成骨细胞核激活因子受体配体(Ligand of receptor activator ofNF-κB,RANKL)mRNA表达后,成骨细胞RANKL、OPG蛋白表达和I型胶原表达、细胞增殖能力的时间变化规律。方法:设计4条RANKL序列特异性小干扰R...目的:观察用RNA干扰的方法抑制大鼠成骨细胞核激活因子受体配体(Ligand of receptor activator ofNF-κB,RANKL)mRNA表达后,成骨细胞RANKL、OPG蛋白表达和I型胶原表达、细胞增殖能力的时间变化规律。方法:设计4条RANKL序列特异性小干扰RNA(siRNA),用Lipofectamin2000转染成骨细胞,采用荧光实时定量聚合酶链反应(PCR)检测RANKL的表达,筛选出最有效的干扰序列,并用Western blot检测转染后1、2、3、5、7天RANKL、OPG蛋白的表达,同时观察成骨I型胶原表达、细胞增殖能力在相同时间点的变化。结果:对siRNA中有一对可使大鼠成骨细胞的RANKLmRNA水平下降89%。用最佳siRNA转染后1、2、3、5、7天,与空白对照组相比,RANKL蛋白表达率分别为59.1%、39.5%、26.6%、40.0%、57.3%(P<0.05),OPG蛋白表达率较空白对照组降低,但差异不具有显著性(P>0.05)。成骨细胞的I型胶原表达、增殖能力在相同时间点较空白对照组降低,差异也不具有显著性(P>0.05)。结论:靶向siRNA可显著下调成骨细胞RANKL表达,同时对OPG表达及成骨细胞的主要功能无显著影响。展开更多
基金This research was made possible as a result of a generous grant from the National Nature Science Foundation of China(grant nos.21877008,32070670,and 22177010)the Zhejiang Provincial Natural Science Foundation of China(grant no.LY21C060003).
文摘Dual labeling of an RNA can provide Förster resonance energy transfer(FRET)sensors for studying RNA folding,miRNA maturation,and RNA-protein interactions.Here,we report the development of a highly efficient strategy for direct dual-terminal labeling of any RNA of interest.We explored new Michael cycloaddition for facile labeling of 5′-terminal RNA with improved efficiency.Direct chemical tetrazinylation of RNA at the 3′-terminus was achieved with the highly efficient and catalysis-free tetrazine-cycloalkyne ligation.Both single-terminal labeling methods were combined for dual-terminal labeling of an RNA including short hairpin RNA,pre-miRNA,riboswitch,and noncoding RNA.Notably,these dual-labeled RNA-based FRET sensors were used to monitor RNA-ligand interactions in vitro and in live cells.It is anticipated that these universal RNA labeling strategies will be useful to study RNA structures and functions.
文摘目的 :探讨大肠癌细胞 Fas配体 (Fas L ) m RNA和蛋白的表达及其功能。方法 :分别采用 RT- PCR和 Western印迹法以及氚释放细胞活性测定技术检测大肠癌细胞株中 Fas L m RNA和蛋白的表达及其功能。结果 :所检测的 6株大肠癌细胞(RPMI 4788、HCT- 116、DL D- 1、L o Vo、Wi Dr和 COL O 32 0 DM)全部表达 Fas L m RNA和蛋白 ;DL D- 1,L o Vo和 Wi Dr等部分大肠癌细胞具有 Fas依赖的细胞毒活性。其中 DL D- 1细胞活性具有量效关系 ,并且乙酸肉豆蔻佛波醇 (PMA )和离子霉素(ionom ycine )刺激能显著增强 DL D- 1的细胞活性。结论 :DL D- 1、L o Vo和 Wi Dr等 3株大肠癌细胞表达功能性 Fas配体 ,并可能以此反击机体免疫系统 ,逃避免疫监督。
