Analysis of differentially expressed genes in response to bacterial stimulation in hemocytes of the carpet-shell clam Ruditapes decussatus: Identification of new antimicrobial peptides

10 páginas, 6 figuras, 2 tablasSuppression subtractive hybridization was used to identify differentiallyexpressedgenes in hemocytes from carpet-shell clam Ruditapes decussatus stimulated with a mixture of dead bacterial strains. Putative function could be assigned to 100 of the 253 sequenced cDNAs. Based on sequence homologies, 3.16% of the total identified genes were possibly related to immune functions. Clam myticin isoforms 1, 2 and 3, and clam mytilin, with similarity with myticins and mytilins previously reported on Mytilus galloprovincialis were identified and characterized for the first time in clams. The analysis of their expression levels by quantitative PCR showed that they were induced by bacterial challenge. The results obtained in this work could be the first step leading to the understanding of molecular mechanisms by which these economically important marine bivalves respond to pathogensThis work has been partially funded by the European Commission through the Marie Curie European Reintegration Project ERG-CT-2005-518007 and the Integrated Research project FOOD-CT-2005-007103, by the Xunta de Galicia (project PGIDIT06PXIC402124A4) and by the Spanish MEC (AGL2003-02454). We thank Philippe Roch for providing the mix of dead bacteria. C.G. wishes to acknowledge additional funding from the Spanish Ministerio de Educación y Ciencia through the “Ramón y Cajal” Contract, and M.M.C. through the FPI Spanish research grant.Peer reviewe