The molecular genetics of the mouse I beta-1,6-N-acetylglucosaminyltransferase locus

Biochem Biophys Res Commun. 2003 Apr 11;303(3):868-76. doi: 10.1016/s0006-291x(03)00443-1.


The I antigen and its precursor, the i antigen, are carbohydrate structures and are found on the surface of most mammalian cells. Conversion of the i to the I structure requires I beta-1,6-N-acetylglucosaminyltransferase activity. The present investigation demonstrates a novel transcript form expressed from the mouse I locus and elucidates the molecular genetics and the genomic organization of the mouse I locus. The mouse I locus was demonstrated to express three transcript forms, one newly identified and two previously reported, which have a different exon 1 but identical exons 2 and 3. The three transcripts were shown to express differentially in various mouse tissues, and all their protein products demonstrated GlcNAc-transferring activity in enzyme function assay. The molecular genetics proposed for the mouse I locus shows that it is homologous to the human I locus. It has been established recently that a defect in the human I locus may lead to the development of congenital cataracts. It was demonstrated that the mouse and the human I transcripts expressed in the epithelium cells of the mouse and human lens, respectively, are homologous forms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • DNA, Complementary / genetics
  • Exons
  • Gene Expression
  • Humans
  • Mice
  • Molecular Biology
  • Molecular Sequence Data
  • N-Acetylglucosaminyltransferases / genetics*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid
  • Tissue Distribution


  • DNA, Complementary
  • RNA, Messenger
  • N-acetylglucosaminyltransferase IGnT
  • N-Acetylglucosaminyltransferases

Associated data

  • GENBANK/AY236873
  • GENBANK/AY236874
  • GENBANK/AY236875