p21在电离辐射诱导EL-4细胞G1期阻滞中的作用

目的 探讨ｐ２１在电离辐射诱导ＥＬ－４细胞Ｇ１期阻滞中的作用。方法 采用Ｎｏｒｔｈ－ｅｒｎ ｂｌｏｔ检测ｐ２１ＷＡＦ１ ｍＲＮＡ水平的变化；采用流式细胞术检测ｐ ２１蛋白表达及细胞周期的变化。结果 ４．０ＧｙＸ射线照射后１２ｈ、２４ｈ、４８ｈＧ１期ＥＬ－４细胞百分数明显高于假照射组：ｐ２１ＷＡＦ１ｍＲＮＡ水平从照射后１ｈ开始升高，４ｈ达峰值，持续至照后１２ｈ；ｐ２１ｘ蛋白表达在照射后２～４８ｈ明显增高。结论 ４．０ＧｙＸ射线照射可诱导ＥＬ－４细胞Ｇ１期阻滞，ｐ２１在电离辐射诱导ＥＬ－４细胞Ｇ１期阻滞中起重要作用。

The role of p21 in G1 arrest of EL-4 cells induced by ionizing radiation

Objective To elucidate the role of p21 in G₁ arrest of EL-4 cells induced by ionizing radiation. Methods Northern blot was used to measure p21 WAF1 mRNA level.Flow cytometry was employed to analyze p21 protein expression and cell cycle of EL-4 cells. Results Following 4.0 Gy X-irradiation, EL-4 cells in G₁ phase began to significantly increase at 12 h, reached the peak at 24 h, and kept at high level till 48 h;the p21 WAF1 mRNA level began to increase at 1 h, reached the peak level at 4 h, kept the high levels till 12 h, then recovered to normal at 24 h;and the level of p21 protein expression in EI-4 cells increased significantly at 2 h to 48 h. Conclusion The results suggest that p21 might play an important role in G₁ arrest of EL-4 cells induced by ionizing radiation.