Pancreatic hormones are peptide

Peptide

Peptides are short polymers of amino acid monomers linked by peptide bonds. They are distinguished from proteins on the basis of size, typically containing less than 50 monomer units. The shortest peptides are dipeptides, consisting of two amino acids joined by a single peptide bond...

s synthesized in pancreatic islets of Langerhans

Islets of Langerhans

The islets of Langerhans are the regions of the pancreas that contain its endocrine cells. Discovered in 1869 by German pathological anatomist Paul Langerhans at the age of 22, the islets of Langerhans constitute approximately 1 to 2% of the mass of the pancreas...

, which acts as a regulator of pancreatic and gastrointestinal functions.

The hormone is produced as a larger propeptide, which is enzymatically cleaved to yield the mature active peptide: this is 36 amino acids in length and has an amidated C terminus. The hormone has a globular structure, residues 2-8 forming a left-handed poly-proline-II-like helix, residues 9-13 a beta turn, and 14-32 an alpha-helix,held close to the first helix by hydrophobic interactions. Unlike glucagon, another peptide hormone, the structure of pancreatic peptide is preserved in aqueous solution. Both N and C termini are required for activity: receptor binding and activation functions may reside in the N and C termini respectively.

Subfamilies

• Pancreatic hormone subtype
• Peptide YY