Project description:Transcriptional profiling of rainbow trout liver cells comparing liver cells from small fish with liver cells from large fish at two time periods.
Project description:Transcriptional profiling of rainbow trout muscle cells comparing muscle cells from small fish with muscle cells from large fish at two time periods.
Project description:Sex steroids play a key role in triggering sec differentiation in fish and the use of exogenous hormone treatment leads to partial or complete sex reversal. This phenomenon has attracted attention since the discovery taht even low environmental doses of exogenous steroids can adversely affect gonad morphology (ovotestis development) and induce reproductive failure. Modern genomic-based technologies have enhanced opportunities to find mechanisms of action (MOA) and dentify biomarkers for the toxic action of a compound. The goal of this study are to improve the understanding of feminization in fish by analyzing gene expression patterns in the gonads of rainbow trout fry after a chronic exposure to several doses (0.01, 0.1, 1 and 10 ?g/L) of ethynylestradiol (EE2) and to offer target genes as potential biomarkers of ovotestis development. An all-male population of Rainbow trout fry was exposed during 76 days (from 60 to 136 days post-fertilization (dpf)) to five nominal concentrations of 17?-ethynylestradiol (0-solvent control-, 0.01, 0.1, 1 and 10 ?g EE2/L of water), using 3 tanks per condition. In total, 30 samples were analyzed independantly: 6 samples per concentration tested (two samples per tank, three tanks per concentration), each sample being a pool of 10 pairs of gonads.
Project description:The sea-run phenotype of rainbow trout (Oncorhynchus mykiss), like other anadromous salmonids, present a juvenile stage fully adapted to life in freshwater known as parr. Development in freshwater is followed by the smolt stage, where preadaptations needed for seawater life are developed making fish ready to migrate to the ocean, after which event they become post-smolts. While these three life stages have been studied using a variety of approaches, proteomics has never been used for such purpose. The present study characterised the blood plasma proteome of parr, smolt and post-smolt rainbow trout using a gel electrophoresis liquid chromatography tandem mass spectrometry approach alone or in combination with low-abundant protein enrichment technology (combinatorial peptide ligand library). In total, 1,822 proteins were quantified, 17.95% of them being detected only in plasma post enrichment. Across all life stages, the most abundant proteins were ankyrin-2, DNA primase large subunit, actin, serum albumin, apolipoproteins, hemoglobin subunits, hemopexin-like proteins and complement C3. When comparing the different life stages, 17 proteins involved in mechanisms to cope with hyperosmotic stress and retinal changes, as well as the downregulation of nonessential processes in smolts, were significantly different between parr and smolt samples. On the other hand, 11 proteins related to increased growth in post-smolts, and also related to coping with hyperosmotic stress and to retinal changes, were significantly different between smolt and post-smolt samples. Overall, this study presents a series of proteins with the potential to complement current seawater-readiness assessment tests in rainbow trout, which can be measured non-lethally in an easily accessible biofluid. Furthermore, this study represents a first in-depth characterisation of the rainbow trout blood plasma proteome, having considered three life stages of the fish and used both fractionation alone or in combination with enrichment methods to increase protein detection.
Project description:The aim of present study is to identify and quantify proteins involved in the events of fertilization and early embryo development using a label-free protein quantification method in rainbow trout (Oncorhynchus mykiss) as an economically important fish species in aquaculture.
Project description:Transcriptional profiling of rainbow trout liver and muscle cells comparing small fish with large fish within a population of neomale offspring.
Project description:Stocking density is considered as a key factor determining the productivity of fish aquaculture systems. The transcriptomic response to crowding stress is, however, still poorly investigated. We aimed at the identification of potential biomarker genes via microarray analyses to get insight into molecular pathways modulated through density-induced stress in farmed rainbow trout Oncorhynchus mykiss. Transcriptome profiling in liver, kidney, and gills was complemented with behaviarol observation and analysis of classical plasma parameters. Individuals of two trout strains were exposed for eight days to definite stocking densities, 1 kg/m³ (low density); 10 kg/m³ (moderate); 18 kg/m³ (elevated); and 35 kg/m³ (high). Whereas stocking density had no significant effect on cortisol levels, plasma glucose levels were elevated in trout kept at high density. Pathway enrichment analyses confirmed the upregulation of HIF1a signaling in liver contributing to glucose homeostasis during stress conditions, while mTOR and PI3K/AKT signaling pathways were downregulated. Further perturbed hepatic pathways were involved in protein ubiquitination and the biosynthesis of cholesterol, retinol and glutathione. Three stocking density conditions were investigated: an uncrowded âmoderateâ density (MD: 10 kg trout/m³) , an elevated density (ED: 18 kg/m³ ), and high density (HD: 35 kg/m³). The experiment was performed twice with two strains of Steelhead rainbow trout (Troutlodge and Born trout), randomly assigned to identical glass tanks with MD (30 and 34 individuals), ED (60 and 64 individuals), and HD (120 and 140 individuals). Trout were sampled 8 d after experimental onset.
Project description:Gene expression in Rainbow trout (Oncorhynchus mykiss) fry gonads after a chronic exposure to a range of 17α-ethynylestradiol concentrations