erbB 受体和 DNA-PKcs 在 erbB1 配体和电离辐射诱导的细胞质和核 Akt S473 磷酸化中的作用。
Function of erbB receptors and DNA-PKcs on phosphorylation of cytoplasmic and nuclear Akt at S473 induced by erbB1 ligand and ionizing radiation.
机构信息
Division of Radiobiology and Molecular Environmental Research, Eberhard Karls University, Tuebingen, Germany.
出版信息
Radiother Oncol. 2011 Oct;101(1):140-6. doi: 10.1016/j.radonc.2011.06.004. Epub 2011 Jun 30.
BACKGROUND AND PURPOSE
In the present study effect of erbB2 as well as DNA-PKcs on ionizing radiation (IR)- and erbB1 ligand-induced phosphorylation of Akt at S473 in cytoplasmic and nuclear fractions was investigated.
MATERIALS AND METHODS
DNA-PKcs proficient and deficient syngeneic colon carcinoma sublines of HCT116 and the glioblastoma cell lines MO59K and MO59J as well as the lung carcinoma cell line A549 were used. Akt-S473 phosphorylation was investigated in cells pre-treated with pharmacological inhibitors or transfected with siRNA by immunoprecipitation, Western blotting and confocal microscopy after different stimuli, i.e., ligands and IR.
RESULTS
IR-induced phosphorylation of Akt in both MO59K and MO59J cell lines but not in HCT116 cells was DNA-PKcs dependent. In A549 cells, IR-induced phosphorylation of nuclear Akt-S473 was dependent on erbB1, erbB2, and DNA-PKcs. EGF induced phosphorylation of nuclear Akt-S473 in a DNA-PKcs and erbB2 independent manner.
CONCLUSION
Data indicate that the function of DNA-PKcs on IR-induced Akt-S473 phosphorylation is cell line specific. IR-induced, but not EGF-induced phosphorylation of cytoplasmic and/or nuclear Akt-S473 is erbB2 dependent.
背景与目的
本研究旨在探究 erbB2 以及 DNA-PKcs 对细胞质和核部分 Akt 在 S473 位点处因电离辐射（IR）和 erbB1 配体诱导而发生的磷酸化的影响。
材料与方法
使用了 DNA-PKcs 功能正常和缺失的同源结肠癌细胞亚系 HCT116 以及胶质母细胞瘤细胞系 MO59K 和 MO59J ，还有肺腺癌细胞系 A549。通过免疫沉淀、Western blot 和共聚焦显微镜，在细胞经药理学抑制剂预处理或转染 siRNA 后，对不同刺激（如配体和 IR）下 Akt-S473 的磷酸化情况进行研究。
结果
IR 诱导的 MO59K 和 MO59J 细胞系中 Akt 的磷酸化依赖于 DNA-PKcs，但在 HCT116 细胞中则不然。在 A549 细胞中，IR 诱导的核 Akt-S473 的磷酸化依赖于 erbB1、erbB2 和 DNA-PKcs。EGF 以 DNA-PKcs 和 erbB2 非依赖性方式诱导核 Akt-S473 的磷酸化。
结论
数据表明，DNA-PKcs 在 IR 诱导的 Akt-S473 磷酸化中的作用具有细胞系特异性。IR 诱导的、而非 EGF 诱导的细胞质和/或核 Akt-S473 的磷酸化依赖于 erbB2。
Zotero 插件