降低细胞内tTG活性可使细胞获得对TNF-α的抗性

Down-regulating the Activity of Transglutaminase Can Endow HeLa Cells with the Resistance to TNF-α

用 Northern印迹证实在 He La细胞中有 t TG的表达 ,且这种表达受 TNF-α的上调 .构建t TG反义真核表达质粒并转染 He La细胞 ,用 G41 8抗性筛选稳定表达的转染细胞 ,并用 Northern印迹和 t TG活性测定进一步分析反义 t TG的转录 .用结晶紫及 MTT法证实阳性细胞克隆获得了对 TNF- α的抗性 ,而转染表达载体 pc DNA3的细胞仍对 TNF- α敏感 .结果表明降低 t TG活性能使细胞对 TNF-

The expression of transglutaminase(tTG) in HeLa cells was detected by Northern blot and the expression of transglutaminase could be up\|regulated by TNF\|α.The anti\|sense tTG cDNA was inserted into the eukaryotic expression vector(pcDNA3) and then transfected into HeLa cells.The stable transfectants were selected by resistance to G418.The expression of anti\|sense tTG was analyzed by Northern blot and tTG activity assay.The stable transfectants were prevented from apoptosis induced by TNF\|α,whereas cells transfected with the expression vector pcDNA3 alone remained susceptible.The level of tTG activity on different cell clones was correlated with their sensitivity to TNF α.This suggested that downregulating the activity of tTG could prevent the cells from apoptosis induced by TNF\|α.