Proenkephalin B (IPR000750)

Short name: Proenkphlin_B

Overlapping homologous superfamilies


Family relationships


Vertebrate endogenous opioid neuropeptides are released by post-translational proteolytic cleavage of precursor proteins. The precursors consist of the following components: a signal sequence that precedes a conserved region of about 50 residues; a variable-length region; and the sequence of the neuropeptide itself. Three types of precursor are known: preproenkephalin A (gene PENK), which is processed to produce 6 copies of Met-enkephalin, plus Leu-enkephalin; preproenkephalin B (gene PDYN), which is processed to produce neoendorphin, dynorphin, leumorphin, rimorphin and Leu-enkephalin; and prepronocipeptin (gene PNOC), whose processing produces nociceptin (orphanin FQ) and two other potential neuropeptides.

Sequence analysis reveals that the conserved N-terminal region of the precursors contains 6 cysteines, which are probably involved in disulphide bond formation. It is speculated that this region might be important for neuropeptide processing [PMID: 8710928].

The primary structure of Sus scrofa (Pig) preproenkephalin B has been elucidated and shown to contain neoendorphin, dynorphin and leumorphin (containing rimorphin as its N terminus). These opioid peptides, each having a Leu-enkephalin structure, act on the kappa-receptor. The sequence similarity observed between preproenkephalin B and preproenkephalin A, coupled with the similarity between their gene organisations, suggests that the two genes have been generated from a common ancestor by gene duplication [PMID: 6316163].

GO terms

Biological Process

GO:0007218 neuropeptide signaling pathway

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.