A Sensitive and Reversible Labeling Strategy Enables Global Mapping of the Core‐Fucosylated Glycoproteome on Cell Surfaces

Abstract Core fucosylation, the attachment of α1,6‐fucose to the innermost N ‐acetylglucosamine (GlcNAc) residue of N ‐glycans, has a strong relationship with tumor growth, invasion, metastasis, prognosis, and immune evasion by regulating many membrane proteins. However, details about the functional mechanism are still largely unknown due to the lack of an effective analytical method to identify cell‐surface core‐fucosylated glycoproteins, and especially glycosylation sites. Here, we developed a sensitive and reversible labeling strategy for probing core fucosylation, by which core‐fucosylated glycoproteins that located on cell‐surface were selectively tagged by a biotinylated probe with high sensitivity. The labeled probe can be further broken enzymatically after the capture by affinity resin. The on‐bead traceless cleavage allowed the global mapping of core‐fucosylated glycoproteins and glycosylation sites by mass spectrometry (MS). The profile of core‐fucosylated glycoproteome provides an in‐depth understanding of the biological functions of core fucosylation.