Metabolic labeling of GlcNAc containing glycans in cells.123
Mode of action
P-GlcNAz is an unnatural N-acetylglucosamine derivative used for the metabolic labeling of GlcNAc residues in cells. P-GlcNAz is passively taken-up by cells, converted to UDP-GlcNAz and incorporated in glycans. Depending on cell type and conditions, P-GlcNAz can give a weak signal and it was found that the conversion of P-GlcNAz to UDP-GlcNAz is not very efficient. This could be overcome by overexpressing AGX2, the rate limiting enzyme required for the production of UDP-GlcNAz.2 Furthermore, UDP-GlcNAz can be epimerized to UDP-GalNAz and vice versa and hence lead to the labeling of GalNAc containing glycans. Another study showed that the labeling efficiency and specificity depended on culture conditions. Under high glucose conditions, P-GlcNAz treatment resulted in N-glycans labeling (labeling signal was sensitive for PNGase-F treatment). Under low glucose conditions, P-GlcNAz labeled mostly intracellular O-GlcNAc residues.3 P-GlcNAz contains an azide group for “click” chemistry using alkyne reagents. These alkynes can be modified with an affinity tag or fluorophore for example.
Metabolic labeling of GlcNAc residues in cells for isolation and visualization.
P-GlcNAz is soluble in DMSO and PBS and is added to cell culture from a stock solution. Glycans decorated with GlcNAz residues can be used to perform “click” chemistry. Please see our click chemistry page for suitable reaction partners.