Deletion of Carboxypeptidase E in Beta Cells Disrupts Proinsulin Processing but Does Not Lead to Spontaneous Development of Diabetes in Mice

Pancreatic beta cell-specific Cpe knockout mice (βCpeKO) lacked mature insulin granules and had elevated proinsulin in plasma; however, glucose-and KCl-stimulated insulin secretion in βCpeKO islets remained intact.