Sodium- and proton-independent thyroid hormones and aromatic acids transporter ( ). Mediates both uptake and efflux of 3,5,3'-triiodothyronine (T3) and 3,5,3',5'-tetraiodothyronine (T4) with high affinity, suggesting a role in the homeostasis of thyroid hormone levels . Responsible for low affinity bidirectional transport of the aromatic amino acids, such as phenylalanine, tyrosine, tryptophan and L-3,4-dihydroxyphenylalanine (L-dopa) (, ). Plays an important role in homeostasis of aromatic amino acids (By similarity).
Subcellular locations: Cell membrane, Basolateral cell membrane
Strongly expressed in kidney and skeletal muscle and at lower level in placenta and heart.