Fig. 1.

The work flow of protein identification and quantification. For the SILAC experiments, the control cells were cultured in Dulbecco's Modified Eagle's Medium containing ‘heavy’ ¹³C₆¹⁵N₄-L-arginine and ¹³C₆¹⁵N₂-L-lysine, while irradiation group cells were maintained in normal ‘light’ medium containing ¹²C₆¹⁴N₄-L-arginine and ¹²C₆¹⁴N₂-L-lysine. The mixtures of Group A and Group B were analyzed by mass spectrum and then explained by SEQUEST.