Roles of p53 in ionizing radiation-induced cell cycle uncoupling
- VernacularTitle:P53在电离辐射诱导的细胞周期解耦联中的作用
- Author:
Shumei MA
;
Limin WU
;
Yang LIU
;
Dan SHI
;
Heqing YI
;
Jieqiong ZHANG
;
Haijiao WANG
;
Xiaodong LIU
- Publication Type:Journal Article
- Keywords:
p53 gene;
Cell cycle uncoupling;
RNAi;
Ionizing radiation
- From:
Chinese Journal of Radiological Medicine and Protection
2008;28(6):597-600
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the roles of p53 in ionizing radiation induced MCF-7 cell cycle uncoupling. Methods The p53 knock-down models was established in MCF-7 with retrovirus packaged particles from 293T cells through calcium acid phosphate co-precipitation, then Western blot was used to detect the protein expression. Flow cytometry(FCM) was used to analyze the cell cycle uncoupling and polyploid after irradiation. Results Compared with p53+/+ group, the percentages of G0/G1 cells in p53 -/- group decreased, while those of S and G2+M increased (P < 0.01). In polyploidy analysis 2N cells decreased, whereas both 4N and 8N cells =increased (P<0.01). Compared with sham-irradiation, 4 Gy X-ray led to the decrease of G0/G1, S cells, and the increase of G2+M cells. The increase of 2N cells and decrease of 4N and 8N cells were observed in both p53+/+ and p53-/- cells. Compared with p53+/+ +IR group, the decrease of G0/G1 and S cells and the increase of C2 + M cells were significant (P < 0.01) in p53-/-+ IR groups. 2N cells decreased, 4N cells increased, but no changes in 8 N cells occurred. Conclusion Radiation might induce G2 arrest and cycle uncoupling, p53 plays a role in the regulation of G2 arrest, but no role in cycle uncoupling.