【摘要】 目的　分离和扩增Egr 1启动子 ,构建pEgr.p TNFα质粒 ,探讨不同辐射剂量对被转染的NIH3T3细胞中TNFα表达的影响。方法　用PCR方法从小鼠基因组DNA中分离并扩增出Egr 1启动子 ,构建pEgr.p TNFα表达质粒 ,脂质体介导的转染法转染小鼠NIH3T3细胞 ,用ELISA方法检测不同剂量X射线照射后的TNFα表达水平。结果　本实验得到的Egr 1启动子序列与报道基本一致 ,Egr 1启动子和TNFαcDNA正确插入表达载体 ;各照射组在不同剂量X射线照射后 8h ,TNFα表达水平均高于假照射组 (P <0 0 5～ 0 0 0 1)。结论　本实验分离和扩增的Egr 1启动子具有辐射激活和诱导下游基因表达增强的功能 ,低剂量辐射可激发并启动下游基因表达 ,在基因 放射联合治疗中有重要意义更多还原

【Abstract】 Objective\ To isolate and amplify Egr\|1 promoter,construct pEgr.p\|TNFα and study its response to different doses of ionizing radiation. Methods\ Egr\|1 promote was isolated from genomic DNA by PCR to construct pEgr.p\|TNFα expression plasmid.Plasmids were transfected into NIH3T3 cells with lipsome and the expression level of TNFα was detected by ELISA after irradiation with different doses of X\|ray . Results\ The sequence of Egr\|1 promoter obtained was essentially same as reported.Egr\|1 promoter and TNF α cDNA was inserted into expression vector correctly.Eight hours after irradiation with different doses of X\|rays,the expression level of TNFα was higher than that of nonirradiated group( P <0 05～0 001). Conclusion\ Egr\|1 promoter obtained can be activated by ionizing irradiation and regulate the expression of downstream gene.Low dose irradiation is for the first time found to be able to induce the expression of the downstream gene.The observation may be of potential significance in tumor therapy.更多还原