SLC7A1, also known as cationic amino acid transporter 1 (CAT1), belongs to the solute carrier family 7 (cationic amino acid transporter, y+ system) and transports cationic amino acids such as arginine, lysine, ornithine, and histidine. SLC7A1 is ubiquitously distributed in human tissues. SLC7A1 may also function as an ecotropic retroviral leukemia receptor and be associated with susceptibility to ecotropic retroviruses.