Definition:

Functions as permease involved in the transport of the cationic amino acids (arginine, lysine and ornithine); the affinity for its substrates differs between isoforms created by alternative splicing. May play a role in classical or alternative activation of macrophages via its role in arginine transport (By similarity).; [Isoform 1]: Functions as permease that mediates the transport of the cationic amino acids (arginine, lysine and ornithine), and it has much higher affinity for arginine than isoform 2.; [Isoform 2]: Functions as low-affinity, high capacity permease involved in the transport of the cationic amino acids (arginine, lysine and ornithine).