Figure 2. The workflow of sample processing. H1299 cells were irradiated and cultivated in a ‘heavy’ or ‘light’ stable isotope labeling by amino acids in cell culture (SILAC) medium. One and 48 h after irradiation, the cells were lysed and samples from the heavy and light media were pooled together to form Set 1 and Set 2, respectively. Samples from both sets were enriched for phosphopeptides, analyzed using mass spectrometry and processed based on the principles of quantitative phosphoproteomics.
