UDP-GlcNAc: BetaGal Beta-1,3-N-Acetylglucosaminyltransferase 1 (B3GNT1), i-Enzyme (iGnT)

Reference work entry


The majority of glycoproteins and glycolipids contain one N-acetyllactosamine unit. However, some of them contain more than one N-acetyllactosamine unit, and they are called poly-N-acetyllactosamines. Poly-N-acetyllactosamines are synthesized by addition of N-acetylglucosamine to galactose terminal of N-acetyllactosamine attached to glycoproteins and glycolipids. This enzyme is thus called N-acetyllactosamine extension enzyme. N-acetyllactosamine repeats are the epitope for i-antibody, which reacts with fetal and umbilical cord human erythrocytes (Fig. 25.1). After birth, the N-acetyllactosamine is extended and then branched to form Galβ1→4GlcNAcβ1→3 (Galβ1→4GlcNAcβ1→6) Galβ1→R, I-antigen. This i to I conversion takes place because of β-1,6-N-acetylglucosaminyltransferase newly appears. Because of this nature, I-antigen-forming enzyme is also called branching enzyme. Conversion of linear poly-N-acetylglucosamine to branched poly-N-acetyllactosamine is the first example of developmental antigen formation in carbohydrates (Fukuda et al. 1979).


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  1. Bao X, Kobayashi M, Hatakeyama S, Angata K, Gullberg D, Nakayama J, Fukuda MN, Fukuda M (2009) Tumor suppressor function of laminin-binding alpha-dystroglycan requires a distinct beta3-N-acetylglucosaminyltransferase. Proc Natl Acad Sci USA 106:12109–12114PubMedCentralPubMedCrossRefGoogle Scholar
  2. Barresi R, Campbell KP (2006) Dystroglycan: from biosynthesis to pathogenesis of human disease. J Cell Sci 119:199–207PubMedCrossRefGoogle Scholar
  3. Buysse K, Riemersma M, Powell G, van Reeuwijk J, Chitayat D, Roscioli T, Kamsteeg EJ, van den Elzen C, van Beusekom E, Blaser S, Babul-Hirji R, Halliday W, Wright, GJ, Stemple DL, Lin YY, Lefeber DJ, van Bokhoven H (2013) Missense mutations in β-1,3-N-acetylglucosaminyltransferase 1 (B3GNT1) cause Walker-Warburg syndrome. Hum Mol Genet 22:1746–1754PubMedCrossRefGoogle Scholar
  4. Fukuda M, Fukuda MN, Hakomori S (1979) Developmental change and genetic defect in the carbohydrate structure of band 3 glycoprotein of human erythrocyte membrane. J Biol Chem 254:3700–3703PubMedGoogle Scholar
  5. Fukuda M (2002) chapter 16, β3-N-acetylglucosaminyltransferase (iGnT). Handbook of glycosyltransferases and related genes. Eds. Taniguchi N, Honke K, Fukuda M (Springer-Verlag Tokyo) pp. 114–124Google Scholar
  6. Grewal PK, Holzfeind PJ, Bittner RE, Hewitt JE (2001) Mutant glycosyltransferase and altered glycosylation of alpha-dystroglycan in the myodystrophy mouse. Nat Genet 28:151–154PubMedCrossRefGoogle Scholar
  7. Kanagawa M, Saito F, Kunz S, Yoshida-Moriguchi T, Barresi R, Kobayashi YM, Muschler J, Dumanski JP, Michele DE, Oldstone MB et al (2004) Molecular recognition by LARGE is essential for expression of functional dystroglycan. Cell 117:953–964PubMedCrossRefGoogle Scholar
  8. Peyrard M, Seroussi E, Sandberg-Nordqvist AC, Xie YG, Han FY, Fransson I, Collins J, Dunham I, Kost-Alimova M, Imreh S et al (1999) The human LARGE gene from 22q12.3-q13.1 is a new, distinct member of the glycosyltransferase gene family. Proc Natl Acad Sci USA 96:598–603PubMedCentralPubMedCrossRefGoogle Scholar
  9. Sasaki H, Bothner B, Dell A, Fukuda M (1987) Carbohydrate structure of erythropoietin expressed in Chinese hamster ovary cells by a human erythropoietin cDNA. J Biol Chem 262:12059–12076PubMedGoogle Scholar
  10. Sasaki K, Kurata-Miura K, Ujita M, Angata K, Nakagawa S, Sekine S, Nishi T, Fukuda M (1997) Expression cloning of cDNA encoding a human β-1,3-N-acetylglucosaminyltransferase that is essential for poly-N-acetyllactosamine synthesis. Proc Natl Acad Sci USA 94:14294–14299PubMedCrossRefGoogle Scholar
  11. Shiraishi N, Natsume A, Togayachi A, Endo T, Akashima T, Yamada Y, Imai N, Nakagawa S, Koizumi S, Sekine S et al (2001) Identification and characterization of three novel beta 1,3-N-acetylglucosaminyltransferases structurally related to the beta 1,3-galactosyltransferase family. J Biol Chem 276:3498–3507PubMedCrossRefGoogle Scholar
  12. Ujita M, McAuliffe J, Hindsgaul O, Sasaki K, Fukuda MN, Fukuda M (1999) Poly-N-acetyllactosamine synthesis in branched N-glycans is controlled by complemental branch specificity of i-extension enzyme and β1,4-galactosyltransferase I. J. Biol Chem 274:16717–16726CrossRefGoogle Scholar
  13. Yoneyama T, Angata K, Bao X, Courtneidge S, Chanda SK, Fukuda M (2012) Fer kinase regulates cell migration through alpha-dystroglycan glycosylation. Mol Biol Cell 23:771–780PubMedCentralPubMedCrossRefGoogle Scholar
  14. Zhou D, Dinter A, Gutierrez Gallego R, Kamerling JP, Vliegenthart JF, Berger EG, Hennet T (1999) A beta-1,3-N-acetylglucosaminyltransferase with poly-N-acetyllactosamine synthase activity is structurally related to beta-1,3-galactosyltransferases. Proc Natl Acad Sci USA 96:406–411PubMedCentralPubMedCrossRefGoogle Scholar

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© Springer Japan 2014

Authors and Affiliations

  1. 1.Sanford-Burnham Medical Research InstituteLa JollaUSA

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