Brain-specific expression of a novel human UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (GalNAc-T9)

摘要

We isolated cDNA coding for the ninth of the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-T9) for human brain by the polymerase chain reaction. The polypeptide encoded by GalNAc-T9 contained the structural features characteristic of GalNAc transferases, such as a GTl motif, a Gal/GalNAc transferase motif, (QXW)_3 repeats, and conserved His, Cys, and acidic amino acid residues. Northern blot analysis revealed the mRNA expression of the enzyme to be confined to the brain. The brain-specific expression of GalNAc-T9 suggested that this isozyme catalyzes O-glycosylation in the brain.