Component of the proteolytic cascade acting downstream of the 26S proteasome in the ubiquitin-proteasome pathway (By similarity). Has a role in regulation of fat storage. Release of an N-terminal tripeptide from a polypeptide. Expressed in intestinal fat-storing cells and some head neurons. RNAi-mediated knockdown causes reduced fat storage but does not affect feeding behavior. Belongs to the peptidase S8 family.