Solute Carrier Family 33, Member 1 (SLC33A1)

The structural diversity and complexity of sugar chains in membrane gangliosides are caused in part by the occurrence of several different species of sialic acid molecules, including O-acetylated forms. Acetylation of sialic acid residues of glycoproteins and gangliosides occurs in the lumen of the Golgi apparatus, using acetyl-CoA as the acetate donor. The predicted 549-amino acid protein contained 6 to 10 transmembrane domains and a leucine zipper motif in transmembrane domain III. Immunofluorescence experiments indicated that the 58-kD protein is localized to the cytoplasm. Using in vitro assays with semi-intact cells, Kanamori et al. (1997) demonstrated that the AT1 protein functioned as an acetyl-CoA transporter. Northern blot analysis revealed that AT1 was expressed as 3.3- and 4.3-kb mRNAs in all tissues tested.