Carboxypeptidase E (CPE) has important functions in processing of endocrine pro-peptides, such as pro-insulin, pro-opiomelanocortin, or pro-gonadotropin-releasing hormone, as evidenced by the hyper-pro-insulinemia, obesity, and sterility of Cpe mutant mice. Down-regulation of Cpe in enlarged placentas of interspecific hybrid (interspecies hybrid placental dysplasia (IHPD)) and cloned mice sugge...