Project description:we report a transgenic zebrafish line using destabilized fluorescent protein, Venus-NLS-PEST (VNP), driven by the promoter of a key circadian clock gene, nr1d1. This system allows us to monitor the development of single-cell circadian rhythm in live zebrafish larva in a cell-type specific manner. To identify the cell types expressing nr1d1:VNP in the whole brain, we conducted single cell RNA-seq (scRNA-seq) of ~15,000 cells dissociated from the brain of Tg(nr1d1:VNP) larval fish at 6.5dpf. Among them, 6514 cells were identified with number of genes > 500 and used for the following analysis. 26 cells clusters were classified from scRNAseq, and manually annotated by comparing the marker genes with the adult zebrfiash whole brain single cell RNA-seq data. The mRNA of nr1d1:VNP was enriched in photoreceptors in pineal gland, granule cells and purkinje cells in cerebellum, habenula cells as well as non-neuron cell.
Project description:Adult zebrafish (Tübingen strain, sex not specified) at approximately 1 year of age were analysed. For experiments conducted under low oxygen conditions, nitrogen gas was bubbled through water to deplete oxygen before exposure of individual fish to the medium. Oxygen concentrations were measured using a dissolved oxygen meter (DO 6+, EUTECH instruments, Singapore). The dissolved oxygen level for hypoxia treatment was measured to be 1.20 ± 0.6 mg/l, whereas normal ambient oxygen levels were 6.6 ± 0.45 mg/l. Zebrafish were exposed to the hypoxic medium for 3 hours. Briefly, after each hypoxia trial, the animals were euthanized by hypothermic shock and then decapitated to remove the brain. Total RNA was extracted from samples mentioned above using the QIAGEN RNeasy mini kit (QIAGEN, GmbH, Hilden, Germany) and stored at â??80°C before further analysis. RNA concentration was determined with a NanoVueâ?¢ UVâ??vis spectrophotometer (GE Healthcare Life Sciences, Fairfield, USA). RNA integrity and quality were then estimated using an Agilent 2100 Bioanalyzer (Agilent Technologies, Palo Alto, CA) and the RNA integrity number (RIN) index was calculated for each sample. Only RNAs with a RIN number >7.0 were processed further. Microarray analysis of gene expression was performed using the Zebrafish Gene 1.0 ST Array (Affymetrix Inc. Santa Clara, CA). Briefly, 300ng of total RNA derived from a single adult brain was converted to amplified sense strand cDNA using the Ambion WT Expression Kit (Life Technologies, Carlsbad, CA). The resulting sense cDNA was fragmented and Biotin end-labelled using the Affymetrix Genechip WT Terminal Labeling Kit prior to hybridisation to the array at 45 °C for 16 hours. Two treatments including hypoxia and normoxia were studied. Each treatment had three biological replicates (i.e. three fish exposed to hypoxia and three fish exposed to normoxia). Six samples were analysed. Microarray analysis of gene expression was performed using the Zebrafish Gene 1.0 ST Array. The signal intensity of the chip was scanned using a GeneChipR Scanner 3000TG and analysed using Expression Console software (www. Affymetrix.com). CEL files were imported and intensities adjusted by RMA background correction and quantile normalization.
Project description:Noise in gene expression renders cells more adaptable to changing environment by imposing phenotypic and functional heterogeneity on genetically identical individual cells. Hence, quantitative measurement of noise in gene expression is essential for the study of biological processes in cells. Currently, there are two complementary methods for quantitatively measuring noise in gene expression at the single cell level: single molecule FISH (smFISH) and single cell qRT-PCR (or single cell RNA-seq). While smFISH has been developed for culture cells, tissue sections and whole-mount invertebrate organisms, the method has not been reported for whole-mount vertebrate organisms. Here, we report an smFISH method that is suitable for whole-mount zebrafish embryo, a popular vertebrate model organism for the studies of development, physiology and disease. We show the detection of individual transcripts for several cell-type specific and ubiquitously expressed genes at the single cell level in whole-mount zebrafish embryo. We also demonstrate that the method can be adapted to detect two different genes in individual cells simultaneously. The whole-mount smFISH method described in this report is expected to facilitate the study of noise in gene expression and its role in zebrafish, a vertebrate animal model relevant to human biology.
Project description:The present study was conducted in the frame of the EU-funded Graphene Flagship project. The aim is to evaluate the impact of graphene oxide (GO) on the (innate) immune system using zebrafish as a model. We previously performed single-cell RNA-sequencing of germ-free zebrafish embryos exposed to GO plus the microbial metabolite butyrate (BA). Here, we performed a follow up experiment using germ-free lck-GFP transgenic fish in which the zebrafish were exposed to GO plus BA at 5 dpf. The embryos were then dissociated and subsequently sorted on lck and submitted for single-cell RNA-sequencing using 10x Genomics.
Project description:We have developed and tested the efficiency of the Tg(myo6b:GFP-2A-rpl10a-3xHA) zebrafish to specifically enrich for and evaluate the translatome of inner ear and lateral line sensory hair cells (IP) compared to the whole fish transcriptome (IN). We show through RNA-seq that HA-tagged ribosome immunoprecipitation significantly enriches for RNA transcripts of known zebrafish hair cell expressed transcripts.
Project description:Using 2 male and 2 female zebrafish (pool of 6) brain samples, we generated base-resolution DNA methylation maps to document sex-specific epigenetic differences. Here we generated single-nucleotide resoultion DNA methylation map of 4 zebrafish brain samples using Reduced Representation Bisulfite Sequencing (RRBS)
Project description:The zebrafish pineal gland (epiphysis) is an autonomous clock organ. In addition to being a site of melatonin production, it contains photoreceptor cells and functions as a circadian clock pace maker, making zebrafish a useful model system to study the developmental control of expression of genes associated with melatonin synthesis and photodetection, and the circadian clock. Here we have used DNA microarray technology to study the zebrafish pineal transcriptome. Analysis of gene expression at five different developmental stages (three embryonic and two adult) has revealed a highly dynamic transcriptional profile, revealing many genes that are highly expressed in the pineal gland. Statistical analysis of the data based on Gene Ontology (GO) annotation indicates that many transcription factors and cell cycle genes are highly expressed during embryonic stages, whereas genes dedicated to visual system signal transduction are preferentially expressed in the adult. Furthermore, several genes were identified that exhibit day/night differences in expression. Our data provide a rich source of candidate genes for distinct functions at different stages of pineal gland development. Experiment Overall Design: Adults and embryos were kept under a 14-hr-light/10-hr-dark cycle. Pineal glands were isolated manually, guided by GFP fluorescence, from embryonic (3d, 5d, and 10d) and adult (3 month and 1-2 yr) transgenic zebrafish in which expression of the GFP gene is driven by the pineal-specific aanat2 promoter. For comparison, brain tissue from which the pineal gland and eyes had been removed was also collected (referred to as “brain”). Altogether, we collected 20 types of samples: five time points (3d, 5d, 10d, 3 mo, and 1-2 yr), two organs (pineal gland and brain), and two sampling times (day and night). For each type of sample, tissue was obtained and processed three to five times. Total RNA was prepared from each sample using the RNeasy Lipid Tissue Mini Kit (Qiagen) and biotin-labeled cDNA was generated using the Ovation Biotin system kit (NeuGen). The Affymetrix GeneChip® Zebrafish Genome Array was hybridized and processed using the standard Affymetrix protocol.
Project description:Transcriptome data from zebrafish single and bulk cells from blood and testes. Blood cells were collected from adult Tg(cd4:mCherry), Tg(cd41:EGFP), Tg(gata1a:GFP), Tg(lyz:DsRed2), Tg(mfap4:tdTomato), Tg(mpx:EGFP), Tg(runx1:mCherry), Tg(tal1:EGFP) and Tubingen Long Fin wild type fish.
Project description:In zebrafish brain, radial glia cells (RG) show a remarkable ability to regenerate damaged neural tissue by reentering cell proliferation and produce neural precursors. To understand how RG respond to brain damage and initiate the regenerative response, we applied single-cell transcriptome analysis to RG in zebrafish adult telencephalon.
Project description:The interaction between neurogenesis and angiogenesis after traumatic brain injury is a complex and dynamic process. To resolve this, we chose the zebrafish model organism for studying brain wound healing via systems biology approach. Transcriptome microarray data and histological analysis of injured fish were sampled at different time points during recovery process. Time-course microarray data following wound healing of zebrafish were obtained. From this set of data, we constructed two intracellular proteinM-bM-^@M-^Sprotein interaction (PPI) networks for the traumatic brain injury healing mechanism. Each fish in each group was injured by a 1.5 mm, 27G needle tip from day 0 to 28, respectively. These injured fish were collected at 0, 0.25, 1, 3, 6, 10, 15, 21, 28 dpi (day post injury). 0.625M-NM-<g of Cy3 cRNA for C. albicans array and 1.65 M-NM-<g of Cy3 cRNA for zebrafish array was fragmented to an average size of about 50-100 nucleotides by incubation with fragmentation buffer at 60M-BM-0C for 30 minutes. Each time point contain two biological repeats.