Aminopeptidase O (IPR033577)

Short name: AOPep

Overlapping homologous superfamilies


Family relationships


Aminopeptidase O (MEROPS identifier M01.028) is an intracellular aminopeptidase with a preference for arginyl bonds. It converts angiotensin III to angiotensin IV. In common with aminopeptidase B and leukotriene A4 hydrolase, aminopeptidase O has a C-terminal extension containing ARM-repeats (named after the Drosophila protein armadillo) [PMID: 15687497]. There is a also a nucleolar location signal located between the peptidase and ARM-repeat domains. Aminopeptidase O has been localized to the nucleolus, and in the mouse a shorter isoform, generated by alternative initiation, is found in adult and embryonic blood vessels, mainly in the endothial and smooth muscle cells [PMID: 17803194]. The AOPEP gene also includes a cluster of microRNAs, one of which modulates expression of the Mef2c gene which encodes myocyte-specific enhancer factor 2C [PMID: 20736237]. It is possible that aminopeptidase O is involved in development of vasculature in the embryo and control of blood pressure.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0070006 metalloaminopeptidase activity

Cellular Component

GO:0005730 nucleolus

Contributing signatures

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