抄録
ATM kinase plays a crucial role in the initiation of signaling pathways in mammalian cells following exposure to IR and other DNA DSB-inducing agents. Loss of function in this protein causes the human disease Ataxia-telangiectasia (AT), characterized by sensitivity to IR, genetic instability, cancer predisposition, and neurodegeneration. Since the only known function of ATM is that of a serine-threonine kinase, we analyzed the subset of phosphorylated proteins in wild-type and ATM-deficient cells using a combination of 32P labeling, selective visualization of phosphorylated proteins in 2DE gels using a phosphoprotein-specific stain (Pro-Q Diamond) and MALDI-TOF mass spectrometry. Using this approach, we were able to generate 2DE phosphoproteome profiles of ATM-deficient cells during DSB-induction. By comparing 2DE profiles of these cells with that from wild-type cells, we were able to identify novel proteins that exhibited differential phosphorylation states in these two cell lines. The possible relation of these putative novel proteins to AT is discussed. [J Radiat Res 44:423 (2003)]
