Global Isotopic Labeling of Protein Digests: Application in Quantitative Proteomics and Phosphoproteomics

摘要

Proteomics has emerged as a new experimental approach because of several important innovations in mass spectrometry (MS) which is now unparalleled in its ability to identify proteins. However, MS still remains mostly qualitative method and requires coupling to other analytical techniques for quantitative profiling of the proteome. Recognized solution for this challenge is the labelling of proteins and peptides with stable isotopes. Several methods have been described based on enzymatic reactions, metabolic labelling or chemical modification with the compounds containing stable isotopes. We developed a new stable isotopic tagging technology (SIMPL) based on global selective N-terminal labelling of the peptides. Here we present applications of SIMPL technology for quantification of complex protein mixtures and identification of protein phosphorylation.