Abstract
Mass spectrometry (MS)-based proteomics is nowadays considered as a mainstream analytical tool for life sciences. This success is mainly to be attributed to the tremendous improvements in the core technology of mass spectrometry coupled with recent developments in bioinformatics and separation sciences. The level of information that is henceforth accessible through MS techniques is broad and encompasses the protein sequence as well as its quantity, modification(s), structure, and implication in macromolecular assemblies. The current chapter focuses on the existing gel-free MS-based quantitative approaches that are applicable in the field of animal sciences and summarizes their principal features together with their respective advantages and drawbacks. In this context, we will discuss both the label-free and label-based relative quantitation strategies as well as the existing alternatives for absolute quantitation. The specific case of posttranslational modifications, whose extensive characterization is becoming a crucial topic in MS-based proteome studies, is next addressed under the quantitative scope of phosphorylation and glycosylation. Lastly, other promising nonmainstream techniques are presented, emphasizing their potent use to solve major proteomics challenges of tomorrow.
Baiwir, Dominique