We propose to study the structure and regulation of two closely linked endocrine genes. We have observed that a gene linked to pancreatic polypeptide (PP) is expressed in isolated pancreatic endocrine cells and pancreatic tissue. Our ultimate aims are to determine the function of this newly described gene and to determine whether this gene shares evolutionary, developmental, regulatory and functional roles with that of PP. PP is an inhibitor of the digestive system and can integrate neural and metabolic information to regulate digestive processes. Pathophysiologically some data suggests PP may be involved with some forms of obesity. Through the use of recombinant DNA we will determine the sequence and structure of the gene products expressed by the two genes at the PP locus. By procedures of in situ hybridization and immunocytochemistry it will be determined whether both genes are expressed in the same cell. By using procedures of tissue culture and mRNA analysis we will determine whether these genes are coregulated.