EXT1:EXT2 transfer GlcNAc to the heparan chain

Stable Identifier
R-HSA-2022851
Type
Reaction
Species
Homo sapiens
Compartment
Synonyms
Another GlcNAc addition extends the heparan chain
Locations in the PathwayBrowser
Summation

Exostosin1 and 2 (EXT1 and 2) are dual specificity enzymes which catalyze the addition of N acetylglucosamine (GlcNAc) and glucuronate (GlcA) to extend the GAG chain on the protein linker sequence. Heparan is synthesized once GlcNAc is transferred to this sequence. EXT1 and 2 form a heterodimer which translocates to the Golgi apparatus from the ER membrane (McCormick et al. 2000). Defects in EXT1 or 2 cause the hereditary bone disorders multiple exostoses type 1 (MIM:133700) and 2 (MIM:133701) (Wuyts et al. 1998, Bernard et al. 2001).

Literature References
PubMed ID Title Journal Year
9463333 Mutations in the EXT1 and EXT2 genes in hereditary multiple exostoses

Wuyts, W, Van Hul, W, De Boulle, K, Hendrickx, J, Bakker, E, Vanhoenacker, F, Mollica, F, Lüdecke, HJ, Sayli, BS, Pazzaglia, UE, Mortier, G, Hamel, B, Conrad, EU, Matsushita, M, Raskind, WH, Willems, PJ

Am J Hum Genet 1998
10639137 The putative tumor suppressors EXT1 and EXT2 form a stable complex that accumulates in the Golgi apparatus and catalyzes the synthesis of heparan sulfate

McCormick, C, Duncan, G, Goutsos, KT, Tufaro, F

Proc Natl Acad Sci U S A 2000
11169766 Diminished levels of the putative tumor suppressor proteins EXT1 and EXT2 in exostosis chondrocytes

Bernard, MA, Hall, CE, Hogue, DA, Cole, WG, Scott, A, Snuggs, MB, Clines, GA, Lüdecke, HJ, Lovett, M, Van Winkle, WB, Hecht, JT

Cell Motil Cytoskeleton 2001
Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
glucuronosyl-N-acetylglucosaminyl-proteoglycan 4-alpha-N-acetylglucosaminyltransferase activity of EXT1:EXT2 [Golgi membrane]
Physical Entity
Activity
Orthologous Events
Authored
Reviewed