glycoconjugated protein signaling pathway proteoglycan signaling pathway PW:0000657 Those pathways initiated or mediated by proteoglycans - heavily glycosylated proteins that have glycosaminoglycan (GAG) chain(s) linked to their protein cores. GAGs are long unbranched polysaccharides of repeating disaccharide units. Proteoglycans are categorized by the nature of the GAG chain or by their size. pathway