junB启动子X射线辐射敏感区域的检测

Analysis of the upstream domain of radiation-induced junB gene

目的探讨junB启动子X射线特异性辐射敏感区。方法构建含250、590、900和1560bpjunB启动子基因片段及CAT报道基因的4种质粒,转染辐射诱导的白血病细胞系L8704细胞,2GyX射线照射,RNA提取,Northern印迹及RNA定量分析。结果含900和1560bpjunB启动子基因片段的质粒组CATRNA表达分别在照射后30和60min达高峰。结论junB启动子590～900bp基因片段为辐射敏感区。

Objective To analyze the upstream domain of radiation-induced junB gene. Methods(Four plasmids) containing 250 bp, 590 bp, 900 bp, 1560 bp separately and CAT reporter gene were constructed and transferred to L8704 cells. The cells were incubated for different time intervals after 2 Gy X-irradiation. Total RNA was extracted from the cells and the fluctuation of CAT mRNA level was assessed by the RNA ratio of CAT/β-actin measured by quantitative Northern blot hybridization. Results CAT mRNA expression containing 900 bp and 1560 bp junB promoter was remarkably and rapidly increased, and reached its peak 30 min after 2 Gy X-irradiation. Conclusion The upstream domain of 590-900 bp junB gene is specifically radiosensitive and plays an important role in the early response of the cells to radiation. ;