title: Insulin-regulated aminopeptidase and its compartment in dendritic cells.
abstract: Peptide epitopes presented by MHC class I molecules are produced through sequential proteolysis, frequently terminating with an aminoterminal trimming step. While the trimming enzymes processing endogenous MHC class I ligands in the endoplasmic reticulum have by now been characterized extensively, we have only recently identified an endosomal enzyme, insulin-regulated aminopeptidase (IRAP) that can trim cross-presented peptides derived from proteins internalized by dendritic cells. Here we summarize the essential features of IRAP as a trimming enzyme, propose an updated model of cellular cross-presentation pathways, and discuss potential additional functions of IRAP and its compartment in dendritic cell biology.
authors.affiliation: Institut National de la Santé et de le Recherche Médicale, Unité 1013, Hôpital Necker, Paris, France.
authors.forename: Loredana
authors.initials: L
authors.lastname: Saveanu
authors.forename: Joël
authors.initials: J
authors.lastname: Babdor
authors.forename: Myriam
authors.initials: M
authors.lastname: Lawand
authors.forename: Peter
authors.initials: P
authors.lastname: van Endert
mesh_terms: D017951:Antigen Presentation / Q000276:immunology; D045142:Cross-Priming; D010122:Cystinyl Aminopeptidase / Q000378:metabolism*; D003713:Dendritic Cells / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000201:enzymology / Q000276:immunology; D011992:Endosomes / Q000201:enzymology / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans
chemical_list: D015395:Histocompatibility Antigens Class I; D010122:Cystinyl Aminopeptidase; C105964:leucyl-cystinyl aminopeptidase