TY - JOUR T1 - Oyster hemocytes express a proline-rich peptide displaying synergistic antimicrobial activity with a defensin A1 - Gueguen,Yannick A1 - Romestand,Bernard A1 - Fievet,Julie A1 - Schmitt,Paulina A1 - Destoumieux Garzon,Delphine A1 - Franck,Vandenbulcke A1 - Philippe,Bulet A1 - Bachere,Evelyne AD - Univ Montpellier 2, CNRS, Ifremer, UMR Ecosyst Lagunaires 5119, F-34095 Montpellier 5, France. AD - Univ Lille 1, EA 3570, Lab Ecol Numer & Ecotoxicol, F-59655 Villeneuve Dascq, France. AD - UJF, CNRS, TIMC IMAG, UMR 5525, F-74160 Archamps, France. AD - UR - https://archimer.ifremer.fr/doc/00000/6232/ DO - 10.1016/j.molimm.2008.07.021 KW - Antimicrobial peptide KW - Mollusk KW - Synergy KW - Invertebrate KW - Innate immunity KW - Pacific oyster N2 - A cDNA sequence that encodes a 61-amino acid polypeptide precursor with homologies to proline-rich antimicrobial peptides (AMPs) was identified in the oyster Crassostrea gigas. After release of a hydrophobic signal peptide. the resulting 37-amino acid peptide, Cg-Prp, is composed of an acidic region and a cationic proline-rich region. To evaluate the biological properties of Cg-Prp, multiple proline-rich peptides corresponding to putative processing of the full-length Cg-Prp were synthesized. A limited antimicrobial activity was observed for two of them, which also showed strong synergistic antimicrobial activity with Cg-Def, a defensin from C gigas. To our knowledge, this is the first evidence of synergy between a defensin and another AMP in an invertebrate. By in situ hybridization, the expression of Cg-prp was found to be restricted to hemocytes and induced following bacterial challenge. Cg-prp transcripts were also detected in hemocytes infiltrating mantle, where Cg-Def is expressed. Additionally, by immunocytochemistry, we showed that Cg-Prp or one of its variants is present in some hemocytes together with defensins. In conclusion, we described here the first proline-rich AMP from mollusk. From our study, it is likely to provide a first line of defense against bacterial invasion by acting through synergy with defensins. (C) 2008 Elsevier Ltd. All rights reserved. Y1 - 2009/02 PB - Elsevier JF - Molecular Immunology SN - 0161-5890 VL - 46 IS - 4 SP - 516 EP - 522 ID - 6232 ER -