Glycan Imaging in Intact Rat Hearts and Glycoproteomic Analysis Reveal the Upregulation of Sialylation during Cardiac Hypertrophy

Citations Over TimeTop 10% of 2014 papers

Abstract

In the heart, glycosylation is involved in a variety of physiological and pathological processes. Cardiac glycosylation is dynamically regulated, which remains challenging to monitor in vivo. Here we describe a chemical approach for analyzing the dynamic cardiac glycome by metabolically labeling the cardiac glycans with azidosugars in living rats. The azides, serving as a chemical reporter, are chemoselectively conjugated with fluorophores using copper-free click chemistry for glycan imaging; derivatizing azides with affinity tags allows enrichment and proteomic identification of glycosylated cardiac proteins. We demonstrated this methodology by visualization of the cardiac sialylated glycans in intact hearts and identification of more than 200 cardiac proteins modified with sialic acids. We further applied this methodology to investigate the sialylation in hypertrophic hearts. The imaging results revealed an increase of sialic acid biosynthesis upon the induction of cardiac hypertrophy. Quantitative proteomic analysis identified multiple sialylated proteins including neural cell adhesion molecule 1, T-kininogens, and α2-macroglobulin that were upregulated during hypertrophy. The methodology may be further extended to other types of glycosylation, as exemplified by the mucin-type O-linked glycosylation. Our results highlight the applications of metabolic glycan labeling coupled with bioorthogonal chemistry in probing the biosynthesis and function of cardiac glycome during pathophysiological responses.

Related Papers

• → The repertoire of glycan determinants in the human glycome(2009)492 cited
• → Glycans and glycan-binding proteins in immune regulation: A concise introduction to glycobiology for the allergist(2015)105 cited
• → Profiling of IgG N-glycome during mouse aging: Fucosylated diantennary glycans containing one Neu5Gc-linked LacNAc are associated with age(2020)15 cited
• → Imaging the Glycome in Living Systems(2012)8 cited
• → Faculty Opinions recommendation of The repertoire of glycan determinants in the human glycome.(2009)