CS-GAG biosynthesis

Chondroitin sulfate (CS) glycosaminoglycan chains consist of N-acetylgalactosamine (GalNAc) residues alternating in glycosidic linkages with glucuronic acid (GlcA). They are bound to the tetrasaccharide linker moiety of core proteins like aggrecan, versican, or decorin. GalNAc residues are sulfated to varying degrees on 4- and/or 6- positions. The steps below describe the biosynthesis of a simple CS chain on a set of possible core proteins (reviewed in Pavao et al. 2006; Silbert & Sugumaran 2002; Mikami & Kitagawa, 2013; Nowicka & Gręda, 2019).

Summary from Reactome (R-HSA-2022870), read 2026-09-23.