ABSTRACT Almost half of proteins have one or more post‐translational glycosylation modifications involving the addition of glycan structures. Proteoglycans are a class of glycosylated proteins with one or more glycosaminoglycan (GAG) chains covalently attached to the core protein. The family currently encompasses a broad collection of 73 glycoconjugates with heparan sulfate and/or chondroitin/dermatan sulfate chains displaying a vast range of different biological functions served by their core protein structures and GAG chains interacting with multiple ligands. These biochemically distinct proteins play numerous roles in biology including development, cancer, ligands for infectious disease, Alzheimer's disease, obesity, diabetes, cardiovascular disease, kidney function and disease, as well as complement regulation, to name a few. Strikingly, 78% of proteoglycans (57/73) have been highlighted to date as potential prognostic markers for one or more cancers. This perspective article discusses recent technological developments in the field of proteoglycans, current and novel approaches to address challenges faced by proteoglycan researchers, as well as future prospects for the field (including the development of a Proteoglycan Atlas) to fully recognize and address the inherent heterogeneity in this class of complex glycoconjugates.
Marissa L. Maciej-Hulme (Wed,) studied this question.