Project description:Tritium is an ubiquist radionuclide which can be found in the environment due to natural and anthropogenic activities, particularly in aquatic ecosystems. In this context, tritium effects on aquatic species such as fish have to be characterized. HTO (tritiated water) effects were therefore investigated in zebrafish, Danio rerio, a common model in toxicology and ecotoxicology with a fully sequenced genome. Experiments were conducted on early life stages. Larvae were exposed to 0.4 and 4 mGy/h of HTO until 10 days post fertilization. Tritium internalization was quantified and effects were investigated using a proteomic analysis. The global analysis of the proteome was performed after protein extraction at 7 and 10 dpf on zebrafish eggs exposed from 3 hpf to 10 dpf.
Project description:This project aimed at identifying developmental stage specific transcript profiles for catecholaminergic neurons in embryos and early larvae of zebrafish (Danio rerio). Catecholaminergic neurons were labeled using transgenic zebrafish strains to drive expression of GFP. At stages 24, 36, 72 and 96 hrs post fertilization, embryos were dissociated and GFP expressing cells sorted by FACS. Isolated RNAs were processed using either polyA selection and libray generation or NanoCAGE. This is the first effort to determine stage specific mRNA profiles of catecholaminergic neurons in zebrafish.
Project description:This study sought to evaluate the effects of dietary MeHg exposure on adult female yellow perch (Perca flavescens) and zebrafish (Danio rerio) reproduction by relating controlled exposures with subsequent reproductive effects. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, and the use of zebrafish allowed for a detailed analysis of the molecular effects of MeHg. MeHg exposures at environmentally relevant levels were done in zebrafish for a full life cycle, mimicking a realistic exposure scenario, and in adult yellow perch for twenty weeks, capturing early seasonal ovarian development. In zebrafish, several genes involved in reproductive processes were shown to be dysregulated by RNA-seq and QPCR, but no significant phenotypic or physiological changes were observed with ovarian staging, fecundity, or embryo mortality. Yellow perch did not appear to be affected by MeHg, either at a molecular level, as assessed by QPCR of eight genes in the pituitary, liver, and ovary tissue, or a physiological level, as seen with ovarian somatic index, circulating estradiol, and ovarian staging. Lack of impact in yellow perch limits the usefulness of zebrafish as a model and suggests that the reproductive sensitivity to environmentally relevant levels of MeHg differs between yellow perch and zebrafish.
Project description:All vertebrates have multiple genes encoding for different CASQ isoforms. Increasing interest has been focused on mammalian and human CASQ genes since mutations of both cardiac (CASQ2) and skeletal (CASQ1) isoforms cause different, and sometime severe, human pathologies Danio rerio (zebrafish) is a powerful model for studying function and mutations of human proteins. In this work expression, biochemical properties and cellular and sub-cellular localization of Danio rerio native CASQ isoforms are investigated. By quantitative PCR three mRNAs were detected in skeletal muscle and one mRNA in heart. Three zebrafish CASQs were identified by mass spectrometry and they share properties with mammalian skeletal and cardiac CASQs. Skeletal calsequestrins were found primarily, but not exclusively, at the sarcomere Z-line level where Terminal Cisternae of Sarcoplasmic reticulum are located.
Project description:Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is a broad spectrum fungicide used extensively in agricultural crops . The aim of this study is to analyse the effects of Chorothalonil on the gene expression profiles in zebrafish (Danio rerio), exposed to two concentrations of the fungicide in the water. Nominal concentrations were 1) Low 0.007mg/l (environmentally relevent) and 2) High 0.035mg/ml . A commercial third generation microarray for Danio rerio (Agielnt V3, 4x44k) was used to identify patterns of gene expression in male livers during a 96h toxicological assay.
Project description:In triplicate for each condition, 12 WT and acbd6 F0 crispant Danio rerio (zebrafish) embryos were incubated with 20 μM YnMyr for 24 h, either between 48-72 hpf or 96-120 hpf. After labelling, zebrafish were washed twice with fresh egg water, deyolked, flash frozen in liquid nitrogen and stored at -80°C until further analysis.
Project description:Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is a broad spectrum fungicide used extensively in agricultural crops . The aim of this study is to analyse the effects of Chorothalonil on the gene expression profiles in zebrafish (Danio rerio), exposed to two concentrations of the fungicide in the water. Nominal concentrations were 1) Low 0.007mg/l (environmentally relevent) and 2) High 0.035mg/ml . A commercial third generation microarray for Danio rerio (Agielnt V3, 4x44k) was used to identify patterns of gene expression in male livers during a 96h toxicological assay. Replicates: Six control, five low and four high concentrations ; 15 samples examined. Expression profiles of male livers compared. Two concentrations of the fungicide chlorothalonil were compared.
Project description:In triplicate for each condition, 12 WT and acbd6 F0 crispant Danio rerio (zebrafish) embryos were incubated with 20 μM YnMyr for 24 h, either between 48-72 hpf or 96-120 hpf. After labelling, zebrafish were washed twice with fresh egg water, deyolked, flash frozen in liquid nitrogen and stored at -80°C until further analysis.
Project description:Embryonic growth trajectory is a risk factor for chronic metabolic and cardiovascular disorders and influences birth weight and early post-natal weight gain in humans. Grb10 is a negative regulator of the main pathways driving embryonic growth. Grb10 knock-out in mammals increases insulin sensitivity and growth trajectory. This study has now investigated the long-term cardiometabolic consequences and associated transcriptomic profiles of morpholino induced early life disruption in grb10a expression in Danio rerio. Transient knockdown increased embryonic growth (+7 %) and metabolic rate (+25 %), while decreasing heart rate (-50 %) in early life. Juvenile growth and respiratory rate were also elevated (+30 % and 7-fold increase respectively). This was associated with permanent remodelling the transcriptional landscape. Multiple growth-related pathways were dysregulated. This study indicates that zebrafish are a suitable model for life-long investigation of the link between early growth and later life disease risk.
