Fig. 1. Experimental layout. Ectodermal and mesendodermal protein extracts were labeled with Cy3 or Cy5 fluorescent dyes, combined and subsequently separated by 2D gel electrophoresis (DIGE). A common standard labeled with Cy2 was used for normalization. The scanned images were analyzed with Proteomweaver software to identify spots that displayed statistically significant changes. Differential spots were cut, digested with trypsin and analyzed by LC-MS/MS. Database searches were performed in Ensembl and TIGR databases using MASCOT.