Mitochondrial transporter of arginine, lysine, homoarginine, methylarginine and, to a much lesser extent, ornithine and histidine (, ). Does not transport carnitine nor acylcarnitines . Functions by both counter-exchange and uniport mechanisms . Plays a physiolocical role in the import of basic amino acids into mitochondria for mitochondrial protein synthesis and amino acid degradation (, ).
Subcellular locations: Mitochondrion inner membrane