Acts as an anion channel mediating the transport of chloride, bromide, iodide, nitrate, sulfate, gluconate, thiocyanate, oxalate and bicarbonate ions (By similarity). Its permeability towards bicarbonate is weak and increases when pH is above 7 (By similarity). Mediates thiocyanate transport in retinal pigment epithelium cells (By similarity). Mediates iodide transport in the thyroid gland, playing an important role in the synthesis of thyroid hormones and the maintenance of thyroid function (By similarity).
Subcellular locations: Basolateral cell membrane, Recycling endosome membrane, Apical cell membrane, Lateral cell membrane
Expressed in the cytoplasm in recycling endosomes of medullary collecting duct cells and in acid-secreting gastric parietal cells. Targeted to the basolateral membrane in hypertonicity and potassium depletion.