Reactome: A Curated Pathway Database

Heparan sulfate/heparin (HS-GAG) metabolism (R-HSA-1638091)

Species Homo sapiens


The acronym HS-GAG is used to describe both heparin and heparan sulfate. HS-GAG is a member of the glycosaminoglycan family and consists of a variably sulfated repeating disaccharide unit, the most common one (50% of the total) being glucuronic acid (GlcA) linked to N-acetylglucosamine (GlcNAc). GlcA can be epimerized to iduronic acid. Higher degrees of sulfation and iduronic acid content in the polysaccharide chain confers the name heparin rather than heparan sulfate to the chain. HS-GAG, like the majority of GAGs in the body, are linked to core proteins, forming proteoglycans (mucopolysaccharides). Two or three HS-GAG chains attach to a core protein on the cell surface or in the extracellular matrix (Sasisekharan & Venkataraman 2000). HS-GAG bound to a core protein can regulate many biological processes such as angiogenesis, blood coagulation and tumour metastasis (Stringer & Gallagher 1997, Tumova et al. 2000). Degradation of HS-GAG is required to maintain a natural turnover of GAGs. Defects in the degradative enzymes result in lysosomal storage diseases, where GAGs build up rather than being broken down and having pathological effects (Ballabio & Gieselmann 2009).

Locations in the PathwayBrowser
Additional Information
GO Biological Process glycosaminoglycan metabolic process (0030203)
Literature References
pubMedId Title Journal Year
9251237 Heparan sulphate Int J Biochem Cell Biol 1997
10716625 Heparan sulfate proteoglycans on the cell surface: versatile coordinators of cellular functions Int J Biochem Cell Biol 2000
19111581 Lysosomal disorders: from storage to cellular damage Biochim Biophys Acta 2009
11102866 Heparin and heparan sulfate: biosynthesis, structure and function Curr Opin Chem Biol 2000