title: Defective processing of neuropeptide precursors in Caenorhabditis elegans lacking proprotein convertase 2 (KPC-2/EGL-3): mutant analysis by mass spectrometry.
abstract: Biologically active peptides are synthesized as larger inactive proprotein peptide precursors which are processed by the concerted action of a cascade of enzymes. Among the proprotein convertases, PC2 is widely expressed in neuro-endocrine tissues and has been proposed to be the major convertase involved in the biosynthesis of neuropeptides. In this study, we have examined the role of the Caenorhabditis elegans orthologue PC2/EGL-3 in the processing of proprotein peptide precursors. We recently isolated and identified 60 endogenous peptides in the nematode C. elegans by two-dimensional nanoscale liquid chromatography - quadrupole time-of-flight tandem mass spectrometry. In the present study, we compare the peptide profile of different C. elegans strains, including PC2/EGL-3 mutants. For this purpose, we used an offline approach in which HPLC fractions are analysed by a matrix-assisted laser desorption ionisation - time of flight mass spectrometer. This differential peptidomic approach unambiguously provides evidence for the role of PC2/EGL-3 in the processing of FMRFamide-like peptide (FLP) precursors and neuropeptide-like protein (NLP) precursors in nematodes.
authors.affiliation: Laboratory of Developmental Physiology, Genomics and Proteomics, Katholieke Universiteit Leuven, Leuven, Belgium. steven.husson@bio.kuleuven.be
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Husson
authors.forename: Elke
authors.initials: E
authors.lastname: Clynen
authors.forename: Geert
authors.initials: G
authors.lastname: Baggerman
authors.forename: Tom
authors.initials: T
authors.lastname: Janssen
authors.forename: Liliane
authors.initials: L
authors.lastname: Schoofs
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000502:physiology; D019835:FMRFamide / Q000235:genetics; D013058:Mass Spectrometry; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology; D009479:Neuropeptides / Q000235:genetics*; D045706:Proprotein Convertase 2 / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D011498:Protein Precursors / Q000235:genetics*; D011499:Protein Processing, Post-Translational; D040901:Proteomics
chemical_list: D029742:Caenorhabditis elegans Proteins; D002135:Calcium-Binding Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D011498:Protein Precursors; C423186:UNC-104 protein, C elegans; C107581:UNC-31 protein, C elegans; D019835:FMRFamide; C473666:EGL-3 proprotein convertase, C elegans; D045706:Proprotein Convertase 2