Xaa-Pro aminopeptidase 2 (XPNPEP2)

Xaa-Pro aminopeptidase 2 (XPNPEP2) is a membrane-bound metalloprotease that catalyzes the removal of a penultimate prolyl residue from the N-terminus of peptides, particularly at Xaa-Pro sequences, where proline is the penultimate residue[2][6][1]. XPNPEP2 plays a role in the degradation of biologically active peptides, including collagen fragments, neuropeptides, hormones, cytokines, and growth factors[1][2][6]. This enzyme is expressed in multiple tissues—both in membrane-anchored and soluble forms—using a glycosylphosphatidylinositol (GPI) anchor for membrane association[1][2][3]. XPNPEP2 participates in the normal breakdown of extracellular matrix components, and its dysregulation has been implicated in pathological processes such as premature ovarian failure due to abnormal collagen accumulation, reproductive senescence, cancer metastasis (notably in prostate cancer), and possible effects tied to exposure to environmental toxins[1][5]. There are currently no widely recognized drugs that specifically target XPNPEP2 in clinical practice, but the enzyme is being studied as a biomarker and potential therapeutic target in disease contexts associated with aberrant peptide processing[1][5].

Other names

X-prolyl aminopeptidase 2Aminopeptidase PAPP2membrane-bound prolyl aminopeptidaseXPNPEP2

Peptidase inhibition (by experimental inhibitors of aminopeptidase P); potentially involved in modulating peptide bioavailability