Figure 2

Comparative phosphoproteomics analysis of EGF-stimulated and unstimulated NPC cells by 2D-DIGE and MS. A, Representative 2D-DIGE gel images. Internal standard labeled with Cy2 (a, blue), phosphoproteins from EGF-unstimulated cells labeled with Cy3 (b, green), phosphoproteins from EGF-stimulated cells labeled with Cy5 (c, red), and overlaying Cy3 and Cy5 images (d, yellow). B, (Left) the 38 differential phosphoprotein spots detected by Decyder software; (Right) a close-up of the region of 2D-DIGE gel images and a 3D simulation of spots 22 and 33. C, MALDI-TOF-MS analysis of differential protein spot 22. Mass spectrum of spot 22 identified as GSTP1 according to the matched peaks is shown (top). Protein sequence of GSTP1 is shown, and matched peptides are labeled in red letters (bottom).