Tags: Protein.
Proenkephalin (PENK) formerly known as proenkephalin A (since proenkephalin B was renamed prodynorphin) is an endogenous opioid polypeptide hormone which via proteolyic cleavage produces the enkephalin peptides [Met]enkephalin and to a lesser extent [Leu]enkephalin. Upon cleavage each proenkephalin peptide results in the generation of four copies of [Met]enkephalin two extended copies of [Met]enkephalin and one copy of [Leu]enkephalin.