Aminopeptidase that plays a central role in peptide trimming, a step required for the generation of most HLA class I- binding peptides. Peptide trimming is essential to customize longer precursor peptides to fit them to the correct length required for presentation on MHC class I molecules. Strongly prefers substrates 9-16 residues long. Rapidly degrades 13-mer to a 9-mer and then stops. Preferentially hydrolyzes the residue Leu and peptides with a hydrophobic C-terminus, while it has weak activity toward peptides with charged C-terminus. May play a role in the inactivation of peptide hormones. May be involved in the regulation of blood pressure through the inactivation of angiotensin II and/or the generation of bradykinin in the kidney. Belongs to the peptidase M1 family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: EC 3.4.11.-; Membrane protein, integral; Protease
Molecular Function: aminopeptidase activity; endopeptidase activity; interleukin-1, Type II receptor binding; interleukin-6 receptor binding; metalloexopeptidase activity; peptide binding; protein binding; zinc ion binding
Biological Process: angiogenesis; antigen processing and presentation of endogenous peptide antigen via MHC class I; antigen processing and presentation of peptide antigen via MHC class I; cell-cell signaling; membrane protein ectodomain proteolysis; peptide catabolic process; regulation of blood pressure; signal transduction