Sodium-independent, high-affinity exchange of anionic amino acids with high specificity for anionic form of cystine and glutamate. Disulfide-linked heterodimer with the amino acid transport protein SLC3A2/4F2hc. Belongs to the amino acid-polyamine-organocation (APC) superfamily. L-type amino acid transporter (LAT) (TC 2.A.3.8) family.