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α4-N-Acetylhexosaminyltransferase (EXTL2)

  • Hiroshi Kitagawa
  • Kazuyuki Sugahara

Abstract

α1,4-N-Acetylhexosaminyltransferase (EXTL2) transfers GalNAc/GlcNAc from UDP- GalNAc/GlcNAc to the tetrasaccharide representing the common glycosaminoglycan (GAG)-protein linkage region (GlcAβ1-3Galβ1-3Galβ1-4Xyl), which is most likely the critical enzyme that determines and initiates heparin/heparan sulfate (HS) synthesis, distinguishing it from the chondroitin sulfate (CS)/dermatan sulfate (DS) synthesis (Kitagawa et al. 1999b). The enzyme is composed of 330 amino acids with one N- glycan and has a type II transmembrane protein topology characteristic of many other glycosyltransferases (Wuyts et al. 1997; Kitagawa et al. 1999b). The enzyme is encoded by the multiple exostoses-like gene EXTL2, a member of the hereditary multiple exos- toses (EXT) gene family of tumor suppressors (Kitagawa et al. 1999b). The enzyme protein is approximately half the size of the other EXT family members that have 676-919 amino acids. The protein shows significant homology with the carboxy- terminus of the other members of the family (Wuyts et al. 1997).

Keywords

Chondroitin Sulfate Linkage Region Dermatan Sulfate Acceptor Substrate Mouse Mastocytoma 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Japan 2002

Authors and Affiliations

  • Hiroshi Kitagawa
    • 1
  • Kazuyuki Sugahara
    • 1
  1. 1.Department of BiochemistryKobe Pharmaceutical UniversityKobeJapan

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