GALNT1

This gene encodes a member of the UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GalNAc-T) family of enzymes. GalNAc-Ts initiate mucin-type O-linked glycosylation in the Golgi apparatus by catalyzing the transfer of GalNAc to serine and threonine residues on target proteins. They are characterized by an N-terminal transmembrane domain, a stem region, a lumenal catalytic domain containing a GT1 motif and Gal/GalNAc transferase motif, and a C-terminal ricin/lectin-like domain. GalNAc-Ts have different, but overlapping, substrate specificities and patterns of expression. Transcript variants derived from this gene that utilize alternative polyA signals have been described in the literature. [provided by RefSeq]

Full Name

UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 1 (GalNAc-T1)

Function

Catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Has a broad spectrum of substrates for peptides such as EA2, Muc5AC, Muc1a, Muc1b and Muc7.

Biological Process

O-glycan processing Source: Reactome
Protein O-linked glycosylation Source: UniProtKB
Protein O-linked glycosylation via serine Source: BHF-UCL
Protein O-linked glycosylation via threonine Source: BHF-UCL
Viral protein processing Source: Reactome

Cellular Location

Polypeptide N-acetylgalactosaminyltransferase 1: Golgi stack membrane
Polypeptide N-acetylgalactosaminyltransferase 1 soluble form: Secreted

Topology

Cytoplasmic: 1-8
Helical: 9-28
Lumenal: 29-559