title: Binding properties of a highly potent and selective iodinated aminopeptidase N inhibitor appropriate for radioautography.
abstract: Aminopeptidase N (APN) is a zinc metallopeptidase involved in the inactivation of biologically active peptides. The knowledge of its precise distribution is crucial to investigate its physiological role. This requires the use of appropriate probes such as the recently developed highly potent and selective radiolabeled APN inhibitor 2(S)-benzyl-3-[hydroxy(1'(R)-aminoethyl)phosphinyl]propanoyl-L-3-[ (12 5)I]iodotyrosine ([(125)I]RB 129). Its binding properties were investigated using rat brain homogenates (K(d)=3.4 nM) or APN expressed in COS-7 cells (K(d)=0.9 nM). The specific binding was 95% at [K(d)], and preliminary autoradiography in intestine is promising. The decreased affinity of [(125)I]RB 129 (=10(-6) M) for the E(350)D APN mutant, supports the critical role of E(350) in the amino-exopeptidase action of APN.
authors.affiliation: Département de Pharmacochimie Moléculaire et Structurale, INSERM U266, CNRS UMR8600, Université René Descartes, UFR des Sciences Pharmaceutiques et Biologiques, 4, Avenue de l'Observatoire, 75270, Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Noble
authors.forename: N
authors.initials: N
authors.lastname: Luciani
authors.forename: S
authors.initials: S
authors.lastname: Da Nascimento
authors.forename: R
authors.initials: R
authors.lastname: Laï-Kuen
authors.forename: L
authors.initials: L
authors.lastname: Bischoff
authors.forename: H
authors.initials: H
authors.lastname: Chen
authors.forename: M C
authors.initials: MC
authors.lastname: Fournié-Zaluski
authors.forename: B P
authors.initials: BP
authors.lastname: Roques
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D001345:Autoradiography / Q000379:methods; D001667:Binding, Competitive; D001921:Brain / Q000166:cytology / Q000201:enzymology; D018826:CD13 Antigens / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D019556:COS Cells; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D006877:Hydroxamic Acids / Q000737:chemistry / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000201:enzymology; D007457:Iodine Radioisotopes; D007470:Monoiodotyrosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D011480:Protease Inhibitors / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D011485:Protein Binding; D051381:Rats; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism; D013552:Swine; D013816:Thermodynamics; D014162:Transfection
chemical_list: C404566:2(S)-benzyl-3-hydroxy(1'(R)-aminoethyl)phosphinylpropanoyl-L-3-iodotyrosine; D006877:Hydroxamic Acids; D007457:Iodine Radioisotopes; D011480:Protease Inhibitors; D011994:Recombinant Proteins; D013438:Sulfhydryl Compounds; C061042:3-(N-hydroxycarboxamido-2-benzylpropanoyl)phenylalanine; C058983:phethiol; D010649:Phenylalanine; D018826:CD13 Antigens; D007470:Monoiodotyrosine