Project description:Investigation of microRNA expression profile of 12, 24, 36 and 48 hours post-fertilization Danio rerio embryos developmentally exposed to retinoic acid. A twelve chip study using total RNA recovered from pools of 75 tropical 5D zebrafish embryos at 12, 24, 36, and 48 hours post fertilization (hpf). Embryos were exposed to control embryo medium or 5 nM retinoic acid from 6-24 hpf, with two biological replicates per condition. Control samples were pooled and hybridized to a single array. 12 miRZebrafish arrays (based on MirBase release 12.0) were used to measure the expression level of 218 mature miRNA from Danio rerio.
Project description:During early neurogenesis, multiple whole animal gene expression profiling studies revealed widespread changes in developmental mRNA and miRNA abundance in ethanol-exposed embryos. Consistent with a role for miRNAs in neurobehavioral development, miRNA target prediction analyses identified multiple miRNAs misexpressed in the ethanol exposed cohorts that were also predicted to target inversely expressed transcripts known to influence brain morphogenesis. [mRNA] A twelve chip study using total RNA recovered from pools of 75 tropical 5D zebrafish embryos at 24 hours post fertilization (hpf). Embryos were exposed to control embryo medium, 100 mM ethanol, or 300 mM ethanol from 4-24 hpf, with four-fold biological redundancy per condition. A single 12x135K Nimblegen array was used to measure the expression level of 38,489 genes from Danio rerio using 60-mer probes, with three-fold technical redundancy. [miRNA] A twelve chip study using miRNA recovered from pools of 75 tropical 5D zebrafish embryos at 12, 24, 36, and 48 hours post fertilization (hpf). Embryos were exposed to control embryo medium or 300 mM ethanol from 4-24 hpf, with two-fold biological redundancy per condition. Control samples were pooled and hybridized to a single array. 12 miRZebrafish arrays (based on MirBase release 12.0) were used to measure the expression level of 218 mature miRNA from Danio rerio, with 12-fold technical redundancy.
Project description:17α-Ethinylestradiol (EE2) is a ubiquitous aquatic contaminant shown to decrease fish fertility at low concentrations, especially in fish exposed during development. The mechanisms of the decreased fertility are not fully understood. In this study, we perform transcriptome analysis by RNA sequencing of testes from zebrafish with previously reported lowered fertility due to exposure to low concentrations of EE2 during development. Fish were exposed to 1.2 and 1.6 ng/L (measured concentration) of EE2 from fertilization to 80 days of age, followed by 82 days of remediation in clean water.
Project description:Bekaert2012 - Reconstruction of D.rerio Metabolic Network
metabolic model accounting for subcellular compartmentalisation (ZebraGEM)
This SBML representation of the D. rerio
(zebrafish) metabolic network is made available under the Creative Commons Attribution-Share Alike 3.0 Unported Licence (see www.creativecommons.org
This model is described in the article:
Reconstruction of Danio rerio Metabolic Model Accounting for Subcellular Compartmentalisation.
PLoS One. 2012;7(11):e49903.
Plant and microbial metabolic engineering is commonly used in the production of functional foods and quality trait improvement. Computational model-based approaches have been used in this important endeavour. However, to date, fish metabolic models have only been scarcely and partially developed, in marked contrast to their prominent success in metabolic engineering. In this study we present the reconstruction of fully compartmentalised models of the Danio rerio (zebrafish) on a global scale. This reconstruction involves extraction of known biochemical reactions in D. rerio for both primary and secondary metabolism and the implementation of methods for determining subcellular localisation and assignment of enzymes. The reconstructed model (ZebraGEM) is amenable for constraint-based modelling analysis, and accounts for 4,988 genes coding for 2,406 gene-associated reactions and only 418 non-gene-associated reactions. A set of computational validations (i.e., simulations of known metabolic functionalities and experimental data) strongly testifies to the predictive ability of the model. Overall, the reconstructed model is expected to lay down the foundations for computational-based rational design of fish metabolic engineering in aquaculture.
This model is hosted on BioModels Database
and identified by: MODEL1204120000
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. PMID: 20587024
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to [CC0 Public Domain Dedication>http://creativecommons.org/publicdomain/zero/1.0/] for more information.
Project description:The possible benefits of selenium (Se) supplementation are currently under investigation for prevention of certain cancers and treatment of neurological disorders. Little is known concerning the response of the brain to increased dietary Se under conditions of Se sufficiency, despite the majority of Se supplementation trials occurring in healthy subjects considered Se sufficient. We evaluated the transcriptional response of the zebrafish (Danio rerio) brain to supplementation with nutritionally relevant levels of dietary Se (sodium selenite) during conditions of assumed Se sufficiency. We used a microarray approach to analyze the global gene expression response of the brain to dietary Se supplementation for 14 days. The experiment used Affymetrix microarrays to compare whole brain RNA from 8 adult zebrafish (Danio rerio) fed a diet with control selenium levels (1.4ppmSe) and 8 fed a diet supplemented with sodium selenite (5.6ppmSe) for 14 days, and with an equal sex ratio within each diet.
Project description:17-ethinylestradiol (EE2) is a synthetic estrogen commonly used as an active substance in oral contraceptives. It is frequently found in waste water effluent and raise concern due to its persistent nature. EE2 binds to estrogen receptors with similar affinity to oestradiol and acts as one of the most potent hormone mimics found in the environment. Estrogen is involved in many aspects of the development of the neuroendocrine system influencing both brain structure and behavior. We and others have reported a significant effect on non-reproductive behaviors in adult fish and in recent studies we found that developmental exposure to EE2 resulted in an anxiogenic phenotype as adults even after a long remediation period. In this study we aim to study possible mechanisms behind the behavior alterations of zebrafish developmentally exposed to EE2 by sequencing the whole brain transcriptome. Zebrafish embryos were exposed to 0, 2.14 and 7.34 ng/L EE2 from 1 day to 80 days post fertilization. After the exposure period a remediation period of 120 days followed before the fish were sampled. 3 male brains from the control group (0 ng/L) and the 2.14 ng/L group were sampled and 3 female brains from the control group (0 ng/L) and 7.34 ng/L were sampled.
Project description:We sequenced strand-specific mRNA from the heads of 3 groups of wild type zebrafish (Danio rerio) 5 days post fertilization. Overall design: Examination of the relative expression of genes in the developing zebrafish brain
Project description:Domoic acid (DA) is a neuroexcitatory amino acid that is naturally produced by some marine diatom species of the genus Pseudo-nitzschia. Ingestion of DA-contaminated seafood by humans results in a severe neurotoxic disease known as amnesic shellfish poisoning (ASP). Clinical signs of ASP include seizures and neuronal damage from activation of AMPA and kainate receptors. However, the impacts of DA exposure at levels below those known to induce outward signs of neurobehavioral exicitotoxicity have not been well characterized. To further understand the mechanisms of neurotoxic injury associated with DA exposure, we examined the transcriptome of whole brains from zebrafish (Danio rerio) receiving intracoelomic (IC) DA at both symptomatic and asymptomatic doses. A majority of zebrafish exposed to high-dose DA (1.2 µg DA/g) exhibited clinical signs of neuroexcitotoxicity (EC50 of 0.86 µg DA/g) within 5 to 20 minutes of IC injection. All zebrafish receiving low-dose DA (0.47 µg DA/g) or vehicle only maintained normal behavior. Microarray analysis of symptomatic and asymptomatic exposures collectively yielded 306 differentially expressed genes (1.5-fold, p = 0.05) predominately represented by signal transduction, ion transport, and transcription factor functional categories. Transcriptional profiles were suggestive of neuronal apoptosis following an overwhelming of protective adaptive pathways. Further, potential molecular biomarkers of neuropathic injury, including Nrdg4, were identified and may be relevant to DA exposure levels below that causing neurobehavioral injury. Our results validate zebrafish as a vertebrate model to study mechanisms of DA neurotoxicity and provide a basis for identifying pathways of DA-induced injury as well as biomarkers of asymptomatic and symptomatic DA exposure levels. Keywords: neurotoxic disease Overall design: To further understand the mechanisms of neurotoxic injury associated with DA exposure, we examined the transcriptome of whole brains from zebrafish (Danio rerio) receiving intracoelomic (IC) DA at both symptomatic and asymptomatic doses. A majority of zebrafish exposed to high-dose DA (1.2 µg DA/g) exhibited clinical signs of neuroexcitotoxicity (EC50 of 0.86 µg DA/g) within 5 to 20 minutes of IC injection. All zebrafish receiving low-dose DA (0.47 µg DA/g) or vehicle only maintained normal behavior. Microarray analysis of symptomatic and asymptomatic exposures collectively yielded 306 differentially expressed genes (1.5-fold, p = 0.05) predominately represented by signal transduction, ion transport, and transcription factor functional categories. All animal studies were carried out under approved IACUC protocols at the University of Washington.