title: Processing of HEBP1 by cathepsin D gives rise to F2L, the agonist of formyl peptide receptor 3.
abstract: The peptide F2L was previously characterized as a high-affinity natural agonist for the human formyl peptide receptor (FPR) 3. F2L is an acetylated 21-aa peptide corresponding with the N terminus of the intracellular heme-binding protein 1 (HEBP1). In the current work, we have investigated which proteases were able to generate the F2L peptide from its precursor HEBP1. Structure-function analysis of F2L identified three amino acids, G(3), N(7), and S(8), as the most important for interaction of the peptide with FPR3. We expressed a C-terminally His-tagged form of human HEBP1 in yeast and purified it to homogeneity. The purified protein was used as substrate to identify proteases generating bioactive peptides for FPR3-expressing cells. A conditioned medium from human monocyte-derived macrophages was able to generate bioactivity from HEBP1, and this activity was inhibited by pepstatin A. Cathepsin D was characterized as the protease responsible for HEBP1 processing, and the bioactive product was identified as F2L. We have therefore determined how F2L, the specific agonist of FPR3, is generated from the intracellular protein HEBP1, although it is unknown in which compartment the processing by cathepsin D occurs in vivo.
authors.affiliation: Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université Libre de Bruxelles, Campus Erasme, B-1070 Brussels, Belgium.
authors.forename: Thalie
authors.initials: T
authors.lastname: Devosse
authors.forename: Raphaël
authors.initials: R
authors.lastname: Dutoit
authors.forename: Isabelle
authors.initials: I
authors.lastname: Migeotte
authors.forename: Patricia
authors.initials: P
authors.lastname: De Nadai
authors.forename: Virginie
authors.initials: V
authors.lastname: Imbault
authors.forename: David
authors.initials: D
authors.lastname: Communi
authors.forename: Isabelle
authors.initials: I
authors.lastname: Salmon
authors.forename: Marc
authors.initials: M
authors.lastname: Parmentier
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D002352:Carrier Proteins / Q000096:biosynthesis / Q000378:metabolism*; D002402:Cathepsin D / Q000172:deficiency / Q000502:physiology*; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000819:agonists* / Q000096:biosynthesis / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D000081062:Heme-Binding Proteins; D006420:Hemeproteins / Q000096:biosynthesis / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D008264:Macrophages / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D010455:Peptides / Q000819:agonists* / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D011498:Protein Precursors / Q000096:biosynthesis / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000276:immunology*; D044042:Receptors, Formyl Peptide / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D002630:Chemotactic Factors; C498127:F2L peptide, human; C469985:FPR3 protein, human; C000631029:HEBP1 protein, human; D000081062:Heme-Binding Proteins; D006420:Hemeproteins; D008024:Ligands; D010455:Peptides; D011498:Protein Precursors; D044042:Receptors, Formyl Peptide; C533922:CTSD protein, human; D002402:Cathepsin D