The voltage-gated proton channel Hv1 is expressed in pancreatic islet ß-cells and regulates insulin secretion.

The voltage-gated proton channel Hv1 is a potent acid extruder that participates in the extrusion of the intracellular acid. Here, we showed for the first time, Hv1 is highly expressed in mouse and human pancreatic islet ß-cells, as well as ß-cell lines. Imaging studies demonstrated that Hv1 resides in insulin-containing granules in ß-cells. Knockdown of Hv1 with RNA interference significantly reduces glucose- and K(+)-induced insulin secretion in isolated islets and INS-1 (832/13) ß-cells and has an impairment on glucose- and K(+)-induced intracellular Ca(2+) homeostasis. Our data demonstrated that the expression of Hv1 in pancreatic islet ß-cells regulates insulin secretion through regulating Ca(2+) homeostasis.