Heteromeric Amino Acid Transporters

The cationic amino acid transporter (CAT) family is comprised of four homologous membrane proteins: CAT-1, CAT-2, CAT-3 and CAT-4, encoded by the Slc7A1−4 genes, respectively. The major difference between these transporters is at the level of tissue specificity and regulation of their expression. The CAT family is included in the Na+-independent transport system, (named system y+) that mediate L-arginine uptake in most tissues and cells.