Modification-specific proteomics: characterization of post-translational modifications by mass spectrometry.

Post-translational modifications generate tremendous diversity, complexity and heterogeneity of gene products, and their determination is one of the main challenges in proteomics research. Recent developments in mass spectrometry based approaches for systematic, qualitative and quantitative determination of modified proteins promise to bring new insights on the dynamics and spatio-temporal control of protein activities by post-translational modifications, and reveal their roles in biological processes and pathogenic conditions. Combinations of affinity-based enrichment and extraction methods, multidimensional separation technologies and mass spectrometry are particularly attractive for systematic investigation of post-translationally modified proteins in proteomics.