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: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:Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent chemicals widely detected in aquatic systems and drinking water. Perfluorononanoic acid (PFNA), a long-chain PFAS, has been reported globally in environmental matrices and fish tis-sues. Although PFNA has been linked to developmental, metabolic, and neurological toxicity, its effects on lipid-related pathways and neurotoxicity remain poorly charac-terized. This study evaluated the developmental and neurotoxic effects of PFNA ex-posure in zebrafish embryos and larvae following a 7-day exposure to environmentally relevant PFNA concentrations. PFNA exposure did not significantly affect survival or deformity rates. Apoptosis was significantly increased in larvae exposed to 1 µg/L PFNA compared to controls, whereas reactive oxygen species were unaffected. Each tested concentration (0.1 µg/L and 10 µg/L) showed a different effect on the zebrafish transcriptome. Low-dose PFNA exposure primarily affected lipid transport, choles-terol metabolism, sphingolipid signaling, and neurodegeneration-related pathways, while high-dose PFNA altered synaptic signaling, axon guidance, and thyroid hormone synthesis. Hypoactivity was observed in the movement of larval zebrafish based on a visual motor response test. Taken together, PFNA exposure leads to molecular changes related to neurotoxicity and lipid metabolism in zebrafish, which may con-tribute to adverse neurodevelopmental outcomes.
Project description:RNAseq was performed on hcar1-4+/+ and hcar1-4-/- zebrafish larvae with (2 h and 4 h) or without (0 h) Pseudomonas aeruginosa (PA) ear infection. The transcriptome profile generated here reveals PA14 infection-induced differential gene expression patterns between hcar1-4-/- and hcar1-4+/+ siblings.