Putative polypeptide N-acetylgalactosaminyltransferase-like protein 1, also known as Polypeptide GalNAc transferase-like protein 1, Protein-UDP acetylgalactosaminyltransferase-like protein 1, UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase-like protein 1, GalNAC-T-like protein 1, pp-GaNTase-like protein 1 and GALNTL1, belongs to the glycosyltransferase 2 family. GALNTL1 plays an important role in the protein modification and protein glycosylation process. GALNTL1 uses the manganese and calcium ion as a cofactor, may catalyze the initial reaction in O-linked oligosaccharide biosynthesis, transfers the N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor.