Insulin hexamer

Insulin is produced by the Islets of Langerhans in the Pancreas of mammals and induces liver and muscle cells to take up glucos (typically after a meal) from the blood. Shown here is a hexameric form, coordinated by two zinc ions, believed to be the form in which it is stored in the beta-cells of the islets of Langerhans prior to release. Inability to produce insulin (forvarious reasons) leads to the common disease of diabetes.