IkappaBalpha degradation is not a requirement for the X-ray-induced activation of nuclear factor kappaB in normal rat astrocytes and human brain tumour cells.
IkappaBalpha degradation is not a requirement for the X-ray-induced activation of nuclear factor kappaB in normal rat astrocytes and human brain tumour cells.
复制标题
在正常大鼠星形胶质细胞和人脑肿瘤细胞中，X 射线诱导的核因子 kappaB 激活不需要 IkappaBalpha 降解。
DOI：
10.1080/095530098141195
复制
发表时间：
1998
影响因子：
2.6
通讯作者：
Tofilon,PJ
中科院分区：
文献类型：
--
作者：
Raju,U;Gumin,GJ;Noel,F;Tofilon,PJ
PurposeTo investigate the mechanism of NF kappa B activation by X-rays in normal primary rat astrocytes.Materials and methodsPrimary cultures of type I astrocytes generated from the cortex of neonatal rats were exposed to X-rays with and without various kinase inhibitors and a protease inhibitor. The nuclear or cytoplasmic protein extracts were collected at specified times after treatment and analysed for NF kappa B-DNA binding activity and I kappa B protein levels.ResultsThe NF kappa B-DNA binding activity was induced by X-rays in a dose- and time-dependent manner in the absence of I kappa B protein degradation in astrocytes as well as in the human glioma cell line U-373MG. Whereas a protease inhibitor (calpain inhibitor 1) and a protein kinase C inhibitor (CGP-41251) did not affect X-ray-induced NF kappa B-DNA binding, treatment of astrocytes with the tyrosine kinase inhibitor (erbstatin) completely prevented the increase in NF kappa B activity after irradiation. Erbstatin also reduced the phosphorylation of I kappa B alpha after X-ray exposure.ConclusionsThese results indicate that, in contrast with the more frequently investigated activators of NF kappa B, radiation-induced activation of this transcription factor proceeds in the absence of I kappa B alpha degradation and requires tyrosine phosphorylation.
