Effect of salt-inducible kinase 2 on checkpoint in response to γ-ray irradiation
10.3760/cma.j.issn.0254-5098.2014.05.005
- VernacularTitle:盐诱导激酶2对放射损伤后细胞周期检查点中的调节作用
- Author:
Jiaojiao YIN
;
Lijun ZHOU
;
Yu WANG
;
Xiaodan LIU
;
Yongqing GU
;
Pingkun ZHOU
- Publication Type:Journal Article
- Keywords:
salt-inducible kinase 2;
Cell cycle;
Histon protein H3;
G2/M checkpoint;
γ-rays
- From:
Chinese Journal of Radiological Medicine and Protection
2014;34(5):338-341
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of salt-induced kinase 2 (SIK2) in the G2/M checkpoint in response to ionizing radiation and the possible mechanism.Methods HeLa cells were irradiated with 60Co γ-rays.The cell model of knockdown SIK2 expression was constrcuted by transfecting HeLa cells with a pSicoR-based lentivirus vector of expressing SIK2 shRNA by lipofectamin 2000.Western blot and flow cytometry were performed to measure the changes of SIK2 protein level and cell cycle distribution.The phosphorylated histone protein H3 on Ser 10 was used as a molecular marker of mitotic cells for detecting the function of G2/M checkpoint.Results The expression level of SIK2 protein increased in HeLa cells after 60Co γ-ray irradiation.A cell model of knockdown SIK2 expression was successfully generated by transfecting the specific shRNA against SIK2.Depression of SIK2 significantly increased the cellular sensitivity at 1,2,4,6 Gy post-irradiation (t =-3.445,-2.581,-3.251,-2.553,P ＜0.05),and led cells to release earlier from the G2/M boundary arrest compared to control cells at 5,6 h post-irradiation (t =4.341,6.500,P ＜ 0.05).Western blot analysis indicated that the irradiation-induced phosphorylated CHK2/T68 in SIK2 knock-down cells was earlier than that in control cells.Conclusions salt-induced kinase 2 (SIK2) participates in the regulation of G2/M checkpoint induced by ionizing radiation and affects cellular radiosensitivity.
