目的用原子力显微镜(atom force microscope,AFM)观察汉坦病毒感染前后Vero-E6细胞的形貌变化。方法①用不同浓度的戊二醛固定细胞;②用不同稀释度的病毒感染细胞;③用同一稀释度的病毒分别感染细胞15、30、45、60、75、90分钟。结果①...目的用原子力显微镜(atom force microscope,AFM)观察汉坦病毒感染前后Vero-E6细胞的形貌变化。方法①用不同浓度的戊二醛固定细胞;②用不同稀释度的病毒感染细胞;③用同一稀释度的病毒分别感染细胞15、30、45、60、75、90分钟。结果①用0.5%和1.0%的戊二醛处理的细胞形态正常;用1.5%和2.0%的戊二醛固定的细胞表面凸凹不平孔洞较多,大部分细胞皱缩。②用不同稀释度的病毒感染过的Vero-E6细胞,与正常细胞相比,细胞表面粗糙,在细胞核周围有孔洞出现,但稀释度不同出现孔洞的数量也有差别,细胞表面光滑程度也有不同。③用同一稀释度的病毒感染细胞不同时间,发现细胞的形貌、表面粗糙度及细胞表面的孔洞数量都有了变化。结论用AFM技术可以观察到病毒感染前后细胞的超微结构,近似的反映出病毒感染细胞的动态过程。展开更多
RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequenc...RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequence. dsRNAmediated RNAi can be used in a wide variety of eucaryotes to induce the sequence-specific inhibition of gene expression.Synthetic 21-23 nucleotide (nt) small interfering RNA (siRNA) with 2 nt 3' overhangs was recently found to mediate efficient sequence-specific mRNA degradation in mammalian cells. Here, we studied the effects of synthetic siRNA duplexes targeted to SARS coronavirus structural proteins E, M, and N in a cell culture system. Among total 26 siRNA duplexes, we obtained 3 siRNA duplexes which could sequence-specifically reduce target genes expression over 80％ at the concentration of 60 nM in Vero E6 cells. The downregulation effect was in correlation with the concentrations of the siRNA duplexes in a range of 0～60 nM. Our results also showed that many inactive siRNA duplexes may be brought to life simply by unpairing the 5' end of the antisense strands. Results suggest that siRNA is capable of inhibiting SARS coronavirus genes expression and thus may be a new therapeutic strategy for treatment of SARS.展开更多
文摘目的用原子力显微镜(atom force microscope,AFM)观察汉坦病毒感染前后Vero-E6细胞的形貌变化。方法①用不同浓度的戊二醛固定细胞;②用不同稀释度的病毒感染细胞;③用同一稀释度的病毒分别感染细胞15、30、45、60、75、90分钟。结果①用0.5%和1.0%的戊二醛处理的细胞形态正常;用1.5%和2.0%的戊二醛固定的细胞表面凸凹不平孔洞较多,大部分细胞皱缩。②用不同稀释度的病毒感染过的Vero-E6细胞,与正常细胞相比,细胞表面粗糙,在细胞核周围有孔洞出现,但稀释度不同出现孔洞的数量也有差别,细胞表面光滑程度也有不同。③用同一稀释度的病毒感染细胞不同时间,发现细胞的形貌、表面粗糙度及细胞表面的孔洞数量都有了变化。结论用AFM技术可以观察到病毒感染前后细胞的超微结构,近似的反映出病毒感染细胞的动态过程。
基金supported by the Grant No.2003AA208215 from the National High Technology Programs of Chinathe Grant No.30270311 from the National Natural Science Foundation of China.
文摘RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequence. dsRNAmediated RNAi can be used in a wide variety of eucaryotes to induce the sequence-specific inhibition of gene expression.Synthetic 21-23 nucleotide (nt) small interfering RNA (siRNA) with 2 nt 3' overhangs was recently found to mediate efficient sequence-specific mRNA degradation in mammalian cells. Here, we studied the effects of synthetic siRNA duplexes targeted to SARS coronavirus structural proteins E, M, and N in a cell culture system. Among total 26 siRNA duplexes, we obtained 3 siRNA duplexes which could sequence-specifically reduce target genes expression over 80％ at the concentration of 60 nM in Vero E6 cells. The downregulation effect was in correlation with the concentrations of the siRNA duplexes in a range of 0～60 nM. Our results also showed that many inactive siRNA duplexes may be brought to life simply by unpairing the 5' end of the antisense strands. Results suggest that siRNA is capable of inhibiting SARS coronavirus genes expression and thus may be a new therapeutic strategy for treatment of SARS.
