cDNA cloning and expression of bovine UDP-N-acetylglucosamine: alpha1, 3-D-mannoside beta1,4-N-acetylglucosaminyltransferase IV

J Biol Chem. 1998 May 8;273(19):11556-62. doi: 10.1074/jbc.273.19.11556.


UDP-N-acetylglucosamine:alpha1,3-D-mannoside beta1, 4-N-acetylglucosaminyltransferase (GnT-IV) is one of the essential enzymes in the production of tri- and tetra-antennary Asn-linked sugar chains. Recently, we have successfully purified GnT-IV from bovine small intestine. Based on the partial amino acid sequence of the purified bovine GnT-IV enzyme, its cDNA has been cloned from bovine small intestine. The open reading frame is 1,605 base pairs long, and this sequence produced GnT-IV activity on transient expression in COS-7 cells. Although the deduced amino acid sequence does not have any significant homology with other known N-acetylglucosaminyltransferases (GnTs), the hydrophobicity profile showed a typical type II transmembrane protein structure, which is common to many glycosyltransferases. N-terminal amino acid sequencing of the purified GnT-IV revealed that 92 amino acids, including a transmembrane region, were truncated during purification. Of the three potential N-glycosylation sites Asn-458 was actually glycosylated in the purified enzyme, although this N-glycosylation site could be abolished without any reduction in GnT-IV activity. Serial deletions at both the N and C termini proved that the catalytic domain of GnT-IV is located in the central region of the enzyme. The GnT-IV mRNA level correlated with enzymatic activity in the various bovine tissues tested.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • COS Cells
  • Cattle
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • Gene Expression
  • Molecular Sequence Data
  • N-Acetylglucosaminyltransferases / genetics*
  • Peptide Mapping
  • RNA, Messenger / genetics
  • Restriction Mapping
  • Sequence Deletion
  • Solubility
  • Structure-Activity Relationship
  • Transfection


  • DNA, Complementary
  • RNA, Messenger
  • N-Acetylglucosaminyltransferases
  • alpha-1,3-mannosylglycoprotein beta-1,4-N-acetylglucosaminyltransferase

Associated data

  • GENBANK/AB000628