A new method for visualizing sugar occupancy in complex biological samples is described online this week in Nature Chemical Biology. This new mass-tagging strategy using polymers to label sugars could provide further knowledge into cardiac muscle survival, cell cycle progression, and synaptic transmission.
Linda Hsieh-Wilson and colleagues found that attaching PEG ― polyethylene glycol ― chains of different molecular weight to glycoproteins enables rapid quantification of cellular glycosylation levels within the cell without the need for protein purification, advanced instrumentation, or expensive radiolabels. This new strategy was then applied to see the effect of phosphorylation on glycosylation. Though current data suggests that phosphorylation should decrease glycosylation, this method revealed an unexpected reverse relationship that was undetectable by previous methods.
This novel mass-tagging strategy will advance the understanding of glycosylation and other post-translational modifications.