Proteomic analysis of radiation-induced alterations in L929 cells

In this study we examined the protein expression profiles in X-irradiated L929 cells to get insight into how mammalian cells respond to radiation-induced cell damage. L929 cells were irradiated with the dose of 6 Gy and cell lysates were collected at different time intervals (20 min, 12, 24, 36, 48 and 72 h). The extracted proteins were separated by 2-DE and quantified using computerized image analysis. Proteins exhibiting significant abundance alterations when comparing irradiated to unirradiated cells were identified by mass spectrometry. Using the proteomics approach we detected 47 proteins that exhibited a significant radiation-induced increase or decrease in the course of 72 h. From this group of spots 28 proteins were identified by mass spectrometry and of these 24 proteins exhibited minimally 2-fold differences in mean abundance values in comparison to controls. The identified proteins represent diverse sets of proteins participating either in protective and reparative cell responses or in induction of apoptosis and oncogenesis. The results document that proteomics is a useful method for unravelling the molecular mechanisms involved in cell reaction to ionizing radiation.