polypeptide N-acetylgalactosaminyltransferase 17; protein-UDP acetylgalactosaminyltransferase 17; UDP-galNAc:polypeptide N-acetylgalactosaminyltransferase 17; polypeptide galNAc transferase 17; galNAc-T17; pp-GaNTase 17 (GALNT17, GALNTL6)

Function

• catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a Ser or Thr on the protein receptor (putative)
• protein modification; protein glycosylation

UDP-N-acetyl-D-galactosamine + polypeptide <--> UDP + N-acetyl-D-galactosaminyl-polypeptide

Cofactor: Mn+2 (putative), Ca+2 (putative)

Structure

• 2 conserved domains in the glycosyltransferase region:
  • N-terminal domain (domain A, GT1 motif), probably involved in Mn+2 coordination & substrate binding
  • C-terminal domain (domain B, gal/galNAc-T motif), probably involved in catalytic reaction & UDP-gal binding
• the ricin B-type lectin domain binds to galNAc & contributes to the glycopeptide specificity (putative)
• belongs to the glycosyltransferase 2 family, galNAc-T subfamily
• contains 1 ricin B-type lectin domain

Compartment

• Golgi apparatus membrane

Alternative splicing

named isoforms=2

More general terms

• galactosyltransferase
• glycoprotein
• membrane protein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:4421
• UniProt: http://www.uniprot.org/uniprot/Q49A17.html