Current evidence suggests that the main mode of action of the NSAID ibuprofen in D. magna relates to interruption of eicosanoid biosynthesis which reduces fecundity. Eicosanoids may therefore play a pivotal selleck chemicals MEK162 role in daphnid reproduction. A wealth of synthetic and natural chemicals may affect invertebrate reproduction through endocrine disruption with one of the best known examples being imposex of female molluscs caused by exposure to tributyl tin. It is therefore important to understand eicosanoid biosyn thesis in Daphnia, and invertebrates in general, to fully rec ognize the potential mode of action of endocrine disrupters and how they may affect natural invertebrate populations. Recently, the genome of D. pulex was fully sequenced, and action within the Daphnia Genomics Consortium has already been taken to start sequencing the D.

magna genome. In the meantime genes identified in Inhibitors,Modulators,Libraries D. pulex serve as a model for understanding eicosanoid bio synthesis, control and disruption in Daphnia. Here we present an overview of the putative eicosanoid biosynthe sis in Daphnia based on annotation of genes from the D. pulex genome supported by recently published transcrip Inhibitors,Modulators,Libraries tomic data of ibuprofen stressed D. magna. Methods Putative genes related to eicosanoid biosynthesis were identified Inhibitors,Modulators,Libraries on the D. pulex genome website through using several bioinformatic search tools such as GO. KEGG and matches against InterPro protein domains. Annotation of these genes were verified through BLAST searches performed against Swissprot protein and non redundant protein sequence databases via the D.

Inhibitors,Modulators,Libraries pulex genome website. Invertebrate and vertebrate COX protein sequences were retrieved from GenBank and Ensembl for phyl ogenetic analysis. Since no arthropod Inhibitors,Modulators,Libraries COX protein sequences were available that could aid the phylogeny with respect to D. pulex, we searched the GenBank Expressed Sequence Tag division using the BLAST algorithm to obtain additional arthro sellckchem pod COX sequences. Sequences that significantly resem bled the sea squirt Ciona intestinalis COX amino acid sequence were retrieved and included in the dataset. Six ESTs were obtained, representing two malacostracan speciesFour ESTs were derived from Homarus americanus and two were derived from Petrolisthes cinctipes. After translating the nucleotide sequences to putative amino acids, it appeared that one H. americanus sequence did not overlap with the other three sequences. The three remain ing sequences constituted two slightly deviating amino acid sequences. DV774102 differed from EH401871 and DV772953. The four H. americanus sequences were com bined to one sequence with variable and missing posi tions specified as unknown. Furthermore, the inferred amino acid sequences of the two P.