Bcl—2基因加强表达对SK细胞编程死亡的效应

TNF和OA诱发人神经母细胞瘤SK细胞编程死亡(PCD)。将编码Bcl-2完整蛋白质的cDNA植入pXJ 41neo载体中,由HCMV病毒启动子控制其表达。形成的正向(pBcl-2-S)及反向(pBcl-2-AS)表达质粒经转染导入SK细胞中获得稳定转染子。Western印迹表明正向转染子表达较大量的26kd Bcl-2蛋白,而反向转染子则不表达。增强表达的Bcl-2基因产物能抑制由TNF引发的PCD,但不影响由OA引发的PCD,从而证明Bcl-2基因产物抗细胞死亡效应的特异性。

EFFECTS OF ENFORCED BCL-2 OVER-EXPRESSION ON THE PROGRAMMED CELL DEATH IN THE HUMAN NEUROBLASTOMA SK CELL LINE

TNF and OA induce cell death in the human neuroblastoma SK cell line with the characteristic features of apoptosis. A 1.6kb cDNA encoding the full-length human Bcl-2 protein was inserted into mammalian expression vector pXJ 41 neo and placed under the control of HMCV promoter in either the sense (pBcl-2-s) or anti-sense (pBcl-2-AS) orientation. The above two plasmids were transfected into SK cells and stable transfectants were obtained. pBcl-2-S-transfected SK cells expressed high level of 26 Kd Bcl-2 protein, as evidenced by Western blotting, while pBcl-2-AS-transfected cells showed no detectable Bcl-2 expression. Over-expressed Bcl-2 protein effectively inhibited TNF-induced, but not OA-induced SK cell death, therefore demonstrating the specificity of Bcl-2 action.