Galnt4 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 highest activity toward EA2 peptide substrate and a much lower activity with EPO-T, Muc2, Muc1a, Muc1b. Protein-UDP acetylgalactosaminyltransferase 4 UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 4 Polypeptide N-acetylgalactosaminyltransferase 4 MAVRWTWAGKSCLLLALLTLAYILVEFSVSTLYASPGAGGARELGPRRLPDLDTREEDLSQPLYIKPPADSHALGEWGRASKLQLNEGELKQQEELIERYAINIYLSDRISLHRHIEDKRMYECKAKKFHYRSLPTTSVIIAFYNEAWSTLLRTIHSVLETSPAVLLKEIILVDDLSDRIYLKAQLETYISNLERVRLIRTNKREGLVRARLIGATFATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVCPVIDTIDWNTFEFYMQTGEPMIGGFDWRLTFQWHSVPKHERDRRTSRIDPIRSPTMAGGLFAVSKKYFQYLGTYDTGMEVWGGENLELSFRVWQCGGKLEIHPCSHVGHVFPKRAPYARPNFLQNTARAAEVWMDEYKEHFYNRNPPARKEAYGDLSERKLLRERLKCKSFDWYLKNVFSNLHVPEDRPGWHGAIRSMGISSECLDYNAPDNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNSVTELCAEVPQQKDYVGMQNCPKDGLPVPVNIIWHFKEDGTIFHPHTRLCLSAYRTAEGRPSVHMKTCDALDKNQLWRFEK Polypeptide GalNAc transferase 4 578 GALT4_MOUSE