Project description:Caligid copepods, also called sea lice, are common ectoparasites of wild and farmed marine fish. The salmon louse Lepeophtheirus salmonis (KrM-xyer, 1837) has emerged as a serious problem for salmon farming in the Northern hemisphere. The annual cost of sea lice to the global salmon mariculture industry has been estimated at M-^@300 million, of which the majority accounts for the cost of chemically treating the farmed salmon. The treatments available for salmonids with sea lice infestation have been limited with a large scale reliance on single products and the use of antiparasitics with similar modes of action, which when used over a long period of time can enhance the selection pressure for reduced sensitivity. The aim of the present study was to identify transcripts whose expression correlated to emamectin benzoate (EMB) susceptibility, or those genes regulated in response to EMB exposure. Two L. salmonis laboratory strains, established from field isolates and differing in susceptibility to EMB were studied using a custom sea louse 15K oligonucleotide microarray and RT-qPCR. Adult male sea lice were sampled from both strains after 1 and 3 hours of aqueous exposure to 0.2 M-5g mL-1 emamectin benzoate, 0.01% PEG300 or sea water. Bioinformatic analysis identified that in the absence of drug treatment, a large number of genes were significantly down regulated in the louse strain hyposensitive to EMB. EMB exposure had marked effects on gene expression in the EMB susceptible strain, but caused little changes in EMB hyposensitive lice. We therefore suggest that transcriptional responses induced by EMB exposure may not be responsible for reduced susceptibility to this antiparasitic compound, but may involve genes that are constitutively expressed in EMB tolerant salmon louse strains.
Project description:modENCODE_submission_3082 This submission comes from a modENCODE project of Michael Snyder. For full list of modENCODE projects, see http://www.genome.gov/26524648 Project Goal: We are identifying the DNA binding sites for 300 transcription factors in C. elegans. Each transcription factor gene is tagged with the same GFP fusion protein, permitting validation of the gene's correct spatio-temporal expression pattern in transgenic animals. Chromatin immunoprecipitation on each strain is peformed using an anti-GFP antibody, and any bound DNA is deep-sequenced using Solexa GA2 technology. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf EXPERIMENT TYPE: CHIP-seq. BIOLOGICAL SOURCE: Strain: OP193(official name : OP193 genotype : unc-119(ed3); wgIs193(sea-2::TY1 EGFP FLAG C; unc-119) outcross : 3 mutagen : Bombard tags : GFP::3xFlag description : This strain's transgene was constructed by Mihail Sarov at the Max Planck Institute for Cell Biology in Tubiginen using Tony Hyman's recombineering pipeline. The resulting plasmid was used for biolistic transformation of an unc-119(ed3) strain. The SEA-2::EGFP fusion protein is expressed in the correct sea-2 spatio-temporal expression pattern. This strain was used for ChIP-seq experiments to map the in vivo binding sites for the SEA-2 transcription factor. made_by : ); Developmental Stage: L3; Genotype: unc-119(ed3); wgIs193(sea-2::TY1 EGFP FLAG C; unc-119); Sex: Hermaphrodite; EXPERIMENTAL FACTORS: Developmental Stage L3; Target gene sea-2; Strain OP193(official name : OP193 genotype : unc-119(ed3); wgIs193(sea-2::TY1 EGFP FLAG C; unc-119) outcross : 3 mutagen : Bombard tags : GFP::3xFlag description : This strain's transgene was constructed by Mihail Sarov at the Max Planck Institute for Cell Biology in Tubiginen using Tony Hyman's recombineering pipeline. The resulting plasmid was used for biolistic transformation of an unc-119(ed3) strain. The SEA-2::EGFP fusion protein is expressed in the correct sea-2 spatio-temporal expression pattern. This strain was used for ChIP-seq experiments to map the in vivo binding sites for the SEA-2 transcription factor. made_by : ); temp (temperature) 20 degree celsius
Project description:We identified cis-regulatory elements based on their dynamic chromatin accessibility during the gastrula-larva stages of sea urchin and sea star and studied their evolution in these echinoderm species