Plays an important role in amino acid transport by acting as binding partner of amino acid transporters SLC6A18 and SLC6A19, regulating their trafficking on the cell surface and their amino acid transporter activity (By similarity). May also play a role in trafficking of amino acid transporters SLC3A1 and SLC7A9 to the renal cortical cell membrane (By similarity). Regulator of SNARE complex function . Stimulator of beta cell replication .
Subcellular locations: Cell membrane
Localizes to the brush border membranes of cells in the proximal tubules of kidney (By similarity). Colocalizes with SLC6A19 in the early proximal S1 tubule (By similarity).
Kidney; collecting ducts. Pancreas; beta cells of islets.