alpha-1,4-galactosyltransferase; UDP-galactose:beta-D-galactosyl-beta1-R 4-alpha-D-galactosyltransferase; alpha-1,4-N-acetylgalactosyltransferase; alpha4Gal-T1; globotriaosylceramide synthase; Gb3 synthase; CD77 synthase; P1/pk synthase (A4GALT, A14GALT, A4GALT1)

Function

• necessary for the biosynthesis of the Pk antigen of blood histogroup P
• catalyzes transfer of galactose to lactosylceramide & galactosylceramide
• necessary for synthesis of receptor for bacterial verotoxins
• protein modification; protein glycosylation

UDP-galactose + beta-D-galactosyl-(1->4)-D-glucosyl-(1<->1)- ceramide
          <-->
UDP + alpha-D-galactosyl-(1->4)-beta-D-galactosyl-(1->4)- D-glucosyl-(1<->1)-ceramide

Structure

• conserved DXD motif is involved in enzyme activity
• belongs to the glycosyltransferase 32 family

Compartment

Golgi membranee)

Expression

• ubiquitous
• highly expressed in kidney, heart, spleen, liver, testis & placenta

Polymorphism

see P blood group

More general terms

• galactosyltransferase

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=53947
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:53947
• OMIM: https://mirror.omim.org/entry/111400
• OMIM: https://mirror.omim.org/entry/607922
• UniProt: http://www.uniprot.org/uniprot/Q9NPC4.html