电离辐射诱导EL-4淋巴瘤细胞G_1期阻滞及相关蛋白的表达

G_1 ARREST AND THE EXPRESSIONS OF RELATIVE PROTEINS IN EL-4 CELLS INDUCED BY IONIZING RADIATION

探讨X射线诱导EL 1细胞G1期阻滞及相关蛋白的表达。采用PI荧光标记 ,流式细胞术检测细胞周期的变化。用单克隆抗体免疫荧光标记 ,流式细胞术检测蛋白表达的变化。结果表明 ,2 0Gy和 4 0Gy照射后 12 72h ,G1期EL 4细胞百分数显著高于假照射组 ( p <0 0 5- p <0 0 0 1)。 4 0Gy照射后EL 4细胞 p53蛋白表达从照射后 2h开始明显增高 ,持续至照射后2 4h ( p <0 0 5- p <0 0 0 1) ;p2 1蛋白表达在照射后 2h开始明显增高 ,持续至照射后 4 8h ( p <0 0 5- p <0 0 0 1) ;GADD4 5蛋白表达在照射后 2h开始明显增高 ,持续至照射后 4 8h ( p <0 0 5- p <0 0 0 1) ;MDM 2蛋白表达在照射后 4h开始明显增高 ,持续至照射后 2 4h ( p <0 0 5- p <0 0 0 1)。结果提示 ,中等剂量X射线照射可诱导EL 4细胞G1期阻滞。p53、p2 1和GADD4 5蛋白表达在电离辐射诱导EL

To investigate G 1 arrest and the expressions of relative proteins in EL 4 cells induced by ionizing radiation,flow cytometry(FCM) was used to analyze cell cycle through staining cells with propidium iodide (PI) .And FCM was also employed to analyze protein expression of EL 4 cells stained wity monoclonal and polyclonal antibodise for their immunofluorescence. It was found that the number of EL 4 cells in G 1 phase increased significantly 12-72h after X irradiation with doses of 2\^0Gy and 4\^0Gy.The resuits also showed significant increases of p53 protein expression at 2h to 24h ( p<0 05-p<0 001 ),p21 protein expression at 2h to 48h ( p<0 05-p<0 001 ),GADD45 protein expression at 2h to 48h( p<0 05-p<0 001 ),and MDM2 protein expression at 4h to 24h ( p<0 05-p<0 001 ) after 4\^0Gy X irradiation.These results suggest that G\-1 arrest of EL 4 cells could be induced by ionizing radiation and the expression of p53,p21 and GADD45 proteins may play an important role in the mechanism.