PREP (Prolyl Oligopeptidase) is a class of serine proteases that are widely involved in protein degradation and metabolic regulation. These enzymes are expressed in various tissues, including the nervous and digestive systems, and are closely related to biological processes such as neurodegenerative diseases and inflammatory responses. Members of the PREP family participate in multiple signaling pathways through specific substrate recognition and cleavage, affecting cell functions and disease progression. Gene expression is strictly regulated, and mutations can lead to changes in enzyme activity, affecting the occurrence and development of diseases.