Aminopeptidases are a class of enzymes widely present in organisms, responsible for catalyzing the removal of amino acids from the N-terminus of proteins or polypeptide chains. This family includes various subtypes such as NPEPPS and LTA4H, each with distinct substrate specificities. They are primarily located in the cytoplasm and cell membrane, participating in biological processes such as protein metabolism, signal peptide processing, and degradation of active peptides. Aminopeptidases play crucial roles in cell signaling pathways, immune responses, and disease development. Their gene expression is specifically regulated, conferring unique functions in different tissues and developmental stages. Mutations or dysregulation in expression are associated with various diseases such as cancer, inflammation, and neurodegenerative disorders.