tailieunhanh - Báo cáo khoa học: Identification and characterization of two dipeptidylpeptidase III isoforms in Drosophila melanogaster

Dipeptidyl-peptidase III (DPP III) hydrolyses small peptides with a broad substrate specificity. It is thought to be involved in a major degradation pathway of the insect neuropeptide proctolin. We report the purification and characterization of a soluble DPP III from 40 gDrosophila melanogas-ter. | iFEBS Journal Identification and characterization of two dipeptidyl-peptidase III isoforms in Drosophila melanogaster Claire Mazzocco1 Jennifer Gillibert-Duplantier2 Veronique Neaud2 Kayoko M. Fukasawa3 Stephane Claverol4 Marc Bonneu4 and Jacques Puiroux1 1 Laboratoire de Neurobiologie des Reseaux CNRS-UMR 5816 Universite Bordeaux I Talence France 2 Groupe de Recherche pour l Etude du Foie INSERM E9917 Universite Victor Segalen Bordeaux II Bordeaux France 3 Department of OralBiochemistry Matsumoto DentalCollege Nagano Japan 4 Plateforme Genomique Fonctionnelle Universite Victor Segalen Bordeaux II Bordeaux France Keywords dipeptidyl-peptidase III enkephalinase neuropeptide proctolin proteomic Correspondence J. Puiroux Laboratoire de Neurobiologie des Reseaux CNRS-UMR 5816 Universite Bordeaux I Avenue des Facultes 33405 Talence Cedex France Fax 33 540 002561 Tel 33 540 002569 E-mail Received 2 November 2005 revised 4 January 2006 accepted 9 January 2006 doi Dipeptidyl-peptidase III DPP III hydrolyses small peptides with a broad substrate specificity. It is thought to be involved in a major degradation pathway of the insect neuropeptide proctolin. We report the purification and characterization of a soluble DPP III from 40 g Drosophila melanogas-ter. Western blot analysis with anti- DPP III serum revealed the purification of two proteins of molecular mass 89 and 82 kDa. MS MS analysis of these proteins resulted in the sequencing of 45 and 41 peptide fragments respectively confirming w 60 of both annotated D. melanogaster DPP III isoforms CG7415-PC and CG7415-PB predicted at 89 and 82 kDa. Sequencing also revealed the specific catalytic domain HELLGH in both isoforms indicating that they are both effective in degrading small peptides. In addition with a probe specific for D. melanogaster DPP III northern blot analysis of fruit fly total RNA showed two transcripts at w and kb consistent with the .