Yan J, Khanna K K, Lavin M F
Queensland Cancer Fund Research Unit, Queensland Institute of Medical Research, Royal Brisbane Hospital, Australia.
Int J Radiat Biol. 1996 May;69(5):539-46. doi: 10.1080/095530096145544.
We used differential display, a method designed to amplify partial cDNA sequences from subsets of mRNAs, to identify mRNAs induced by ionizing radiation in human Epstein Barr Virus (EBV)-transformed lymphoblastoid cells. Increased expression of a cDNA corresponding to the inositol 1,4,5 trisphosphate receptor (InsP3R) type 1 was observed after exposure of cells to 3Gy gamma-rays. This was confirmed by Northern blot analysis. The increase in mRNA for InsP3R type 1 was accompanied by a corresponding increase in the level of InsP3R type 1 protein as determined by Western blotting. Exposure of cells from patients with the human genetic disorder ataxia-telangiectasia (A-T), characterized by hypersensitivity to ionizing radiation, failed to change the levels of InsP3R type 1 mRNA and, as expected, there was no increase in InsP3R type 1 protein in A-T cells in response to radiation exposure. Protein levels for two other InsP3Rs, types 2 and 3, were observed to increase in control and A-T cells after exposure to ionizing radiation. The induction of the InsP3R type 1, which is primarily located in the endoplasmic reticulum, may play an important role in radiation signal transduction.
我们采用差异显示法（一种旨在从mRNA亚群中扩增部分cDNA序列的方法）来鉴定电离辐射在人爱泼斯坦-巴尔病毒（EBV）转化的淋巴母细胞中诱导产生的mRNA。在细胞暴露于3Gyγ射线后，观察到与1型肌醇1,4,5-三磷酸受体（InsP3R）相对应的cDNA表达增加。这通过Northern印迹分析得到证实。如通过蛋白质免疫印迹法所测定的，1型InsP3R的mRNA增加伴随着1型InsP3R蛋白水平相应增加。患有人类遗传性疾病共济失调-毛细血管扩张症（A-T）的患者的细胞，其特征为对电离辐射过敏，在辐射暴露后未能改变1型InsP3R mRNA的水平，并且正如预期的那样，A-T细胞中的1型InsP3R蛋白没有因辐射暴露而增加。在对照细胞和A-T细胞暴露于电离辐射后，观察到另外两种InsP3R（2型和3型）的蛋白水平增加。主要位于内质网的1型InsP3R的诱导可能在辐射信号转导中起重要作用。
