The function of SLC30A8 (solute carrier family 30 member 8, Ensembl gene identifier ENSG00000164756) is as follows. Proton-coupled zinc ion antiporter mediating the entry of zinc into the lumen of pancreatic beta cell secretory granules, thereby regulating insulin secretion. {ECO:0000269|PubMed:15331542, ECO:0000269|PubMed:16984975, ECO:0000269|PubMed:27875315, ECO:0000269|PubMed:32723473}.