Permease involved in the transport of the cationic neutral or acidic amino acids. Expressed in roots, stems, flowers and leaves. Mostly present in young and rapidly dividing tissues such as the shoot and root apical meristem, and in young leaves and petioles during seedling development. Belongs to the amino acid-polyamine-organocation (APC) superfamily. Cationic amino acid transporter (CAT) (TC 2.A.3.3) family.