首都医科大学学报 ›› 2011, Vol. 32 ›› Issue (2): 244-248.

• 基础研究 • 上一篇    下一篇

缺氧影响PTEN磷酸化和核定位

周云英1,刘华1,郭锐翰2,杨龙艳1,卞伟华1,贺俊崎1*   

  1. 1. 首都医科大学基础医学院生物化学与分子生物学系; 2. 首都医科大学2007级五年制基础医学专业基础医学班
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2011-04-21 发布日期:2011-04-21
  • 通讯作者: 贺俊崎

Effects of Hypoxia on PTEN Phosphorylation and Nuclear Localization

ZHOU Yun-ying1, LIU Hua1, GUO Rui-han2, YANG Long-yan1, BIAN Wei-hua1, HE Jun-qi1*   

  1. 1. Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Capital Medical University;2. Fiveyear Program of Basic Medical Classes, Major in Basic Medical Science, Capital Medical University
  • Received:1900-01-01 Revised:1900-01-01 Online:2011-04-21 Published:2011-04-21
  • Contact: HE Jun-qi

摘要:

目的 观察缺氧(hypoxia)对第10号染色体缺失并与张力蛋白同源的磷酸酶(phosphatase and tension homolog deleted on chromosome ten,PTEN)磷酸化及核定位的影响。
方法 以1% O2条件下培养的COS-7细胞为缺氧模型,在缺氧处理不同时间点0、1、8、24、32 h收集细胞,应用Western blotting方法检测PTEN磷酸化水平及其下游信号分子磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)的表达变化;分别应用细胞核、质分离技术,共聚焦显微镜观察缺氧24 h前后PTEN亚细胞定位的变化。
结果 COS-7细胞缺氧处理24 h与未缺氧对照细胞相比,PTEN磷酸化水平显著降低,p-Akt亦明显减少;细胞核中PTEN表达量则显著升高。
结论 PTEN磷酸化水平和核质分布受到细胞缺氧的调节。在细胞缺氧反应中,PTEN去磷酸化而活化,通过抑制其下游分子Akt磷酸化,从而抑制缺氧诱导的细胞增殖信号通路活化;并且部分入核发挥核内PTEN功能。

关键词: 第10号染色体缺失并与张力蛋白同源的磷酸酶, 缺氧, 磷酸化, 亚细胞定位

Abstract:

Objective To investigate the effects of hypoxia on endogenous phosphatase and tension homolog deleted on chromosome ten(PTEN) phosphorylation and nuclear localization.
Methods COS-7 cells were cultured in hypoxic condition(1% O2) and harvested at 0, 1, 8, 24, 32 h. Each lysate was used to detect p-PTEN and PTEN downstream molecule p-Akt expression by Western blotting. Subcellular localization of PTEN was observed at 0, 24 h with hypoxic treatment by nucleus and plasma separation method and confocal microscopy respectively.
Results Upon hypoxic treatment for 24 h, phosphorylated PTEN level decreased significantly,accompanied by p-Akt expression level decrease; and nuclear PTEN level increase.
Conclusion In response to hypoxia treatment, PTEN was activated due to decrease of phosphorylated PTEN level, then PTEN inhibited downstream Akt activation. Under hypoxic condition, PTEN was promoted to enter nucleus.

Key words: phosphatase and tension homolog deleted on chromosome ten, hypoxia, phosphorylation, subcellar distribution

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