The protein encoded by this gene is a post-proline cleaving aminopeptidase expressed in quiescent lymphocytes. The resting lymphocytes are maintained through suppression of apoptosis, a state which is disrupted by inhibition of this novel serine protease. The enzyme has strong sequence homology with prolylcarboxypeptidase and is active at both acidic and neutral pH. [provided by RefSeq, Jul 2008].