Proton-coupled zinc ion antiporter mediating the entry of zinc into the lumen of pancreatic beta cell secretory granules, thereby regulating insulin secretion.
Subcellular locations: Cytoplasmic vesicle, Secretory vesicle membrane, Cell membrane
Associated with insulin and glucagon secretory granules.
In the endocrine pancreas, expressed in insulin-producing beta cells. Expressed at relatively high levels in subcutaneous fat tissue from lean persons; much lower levels in visceral fat, whether from lean or obese individuals, and in subcutaneous fat tissue from obese individuals. Expressed in peripheral blood mononuclear cells, including T-cells and B-cells, with great variation among individuals ranging from negative to strongly positive.