Updated project metadata. In this study, we systematically assessed the fine-tuning of limited proteolysis in the extracellular space by glycosylation, one of the most widely observed PTMs, using cells, and applying the Terminal Amine Labeling of Substrates (TAILS) approach, a quantitative proteomics workflow for the system-wide assessment of protein N termini and protease cleavage events in complex biological samples. In addtion, we complement the study with DIA analysis, PRM and glycoproteomics analysis for further validation of the initial observations