Project description:Recently, omics techniques have been widely applied to the discovery of potential bio-markers and explore triggering mechanism. To get a more comprehensive diagnosis of HBCD impacts on marine medaka (Oryzias melastigma), the larvae (within 24 hours post-hatch) were exposed to gradient doses of HBCD. After exposure for 7 days, the profiles of genes expression were examined using a custom-commercial 26, 430-oligonucleotide arrays (4×44K) of Japanese medaka which is shared much genomic information with marine medaka.At the end of the treatment period, 30 larvae/sample were pooled for RNA extraction and labeled by One-Color. A total of twelve independent arrays: three control (DMSO), three low-concentration HBCD (0.2 nM) exposures, three medium-concentration HBCD (2 nM) exposures, and three high-concentration HBCD (20 nM) exposures.
Project description:Recently, omics techniques have been widely applied to the discovery of potential bio-markers and explore triggering mechanism. To get a more comprehensive diagnosis of HBCD impacts on marine medaka (Oryzias melastigma), the larvae (within 24 hours post-hatch) were exposed to gradient doses of HBCD. After exposure for 7 days, the profiles of genes expression were examined using a custom-commercial 26, 430-oligonucleotide arrays (4M-CM-^W44K) of Japanese medaka which is shared much genomic information with marine medaka.At the end of the treatment period, 30 larvae/sample were pooled for RNA extraction and labeled by One-Color. A total of twelve independent arrays: three control (DMSO), three low-concentration HBCD (0.2 nM) exposures, three medium-concentration HBCD (2 nM) exposures, and three high-concentration HBCD (20 nM) exposures. The larvae of marine medaka (within 24 hours post-hatch) were exposed to to 0 (control), 0.2nM, 2nM and 20nM of HBCD (dimethyl sulfoxide with a final concentration of 1:30000 v/v water) for 7 days. Each HBCD treatment had three replicates with 100 larvae for each Petri dish. At the end of the treatment period, 30 larvae/sample were pooled for RNA extraction. A total of twelve independent arrays: three control (DMSO), three low-concentration HBCD (0.2 nM) exposures, three medium-concentration HBCD (2 nM) exposures, and three high-concentration HBCD (20 nM) exposures.
Project description:Persistent and ubiquitous organic pollutants, such as the polycyclic aromatic hydrocarbon benzo[⍺]pyrene (BaP), represent a major threat to aquatic organisms and human health. Beside some well-documented adverse effects on the development and reproduction of aquatic organisms, BaP was recently shown to affect fish bone formation and skeletal development through mechanisms that remain poorly understood. In this work, several bone-related in vivo assays were used in zebrafish to evaluate the osteotoxic effects of BaP during bone development and regeneration. Exposure to BaP for 3 days induced a dose-dependent reduction of the size of the opercular bone in 6 days post-fertilization (dpf) larvae, and affected osteoblast maturation as observed by the expression of the mature marker, osteocalcin. Exposure to BaP for 27 days affected the development of the axial skeleton and increased the incidence and severity of skeletal deformities. During bone regeneration, BaP affected the mineralization of newly formed fin rays and scales, while it impaired fin ray patterning and scale shape, through mechanisms that may involve an imbalance of bone remodeling. Transcriptomic and gene expression analyses indicate that BaP induced the activation of xenobiotic and metabolic pathways, while negatively impacting extracellular matrix formation and organization. Interestingly, BaP exposure positively regulated inflammation markers in 6 dpf larvae and increased neutrophil recruitment. A direct interaction between neutrophils and bone extracellular matrix or bone forming cells was observed in vivo, suggesting a role for neutrophils in the mechanisms underlying BaP osteotoxicity. Our work provides novel data on the cellular and molecular players involved in BaP osteotoxicity and brings new insights into a possible role for neutrophils in inflammatory bone reduction.
Project description:The anabolic androgen 17M-NM-2-trenbolone (TB) can cause masculinization and reduce fecundity of fish. However, the underlying mechanisms of various biological pathways including metabolism, biosynthesis etc. are largely unknown. Here, we evaluated the effects of TB using the medaka DNA microarray representing 36,398 genes. Larval medaka, Oryzias latipes, (within 24 hrs posthatch) were exposed to TB at various concentrations (2, 6, 20, 60, 100, 200 ng/L) for up to 7 days. Dose-response relationships in gene expression levels of the categorized genes were analyzed using the cumulative chisquared method. Microarray analyses of the TB-exposed larvae showed that 117 and 32 genes were determined as up and down-regulated genes, respectively. The most significant GO term for biological process identified within this gene list was lipid metabolic process, which contained 26 genes in up-regulated genes. In this category, M-bM-^@M-^\cholesterol biosynthetic processM-bM-^@M-^] was highlighted as an important subcategory with 15 genes, including hydroxymethylglutaryl-CoA synthase cytoplasmic, squalene monooxygenase, lanosterol synthase etc. RT-PCR measurements in these genes were consistent with the microarray results in the direction and magnitude of these changes in gene expression. On the other hands, in the category of M-bM-^@M-^\sexual differentiation and developmentM-bM-^@M-^], genes related to hypothalamic-pituitary-gonadal (HPG) axis were not affected by TB treatment except for one gene encoded to cytochrome P450 19A1. Genes related to oogenesis, such as choriogenins and vitellogenins were weakly down regulated at 2-200 ng/L of TB. Our findings demonstrate that genes encoding cholesterol synthesis pathway via the mevalonate pathway were controlled by TB in larval medaka. TB concentrations used were 0 (control), 2, 6, 20, 60, 100 and 200 ng/L for 7 days of exposure. Each TB treatment had 90 larval medaka for each chamber. At day 7 of the exposures, triplicate samples (30 larvae/sample) from each chamber respectively were collected, flash-frozen in liquid nitrogen, and stored in liquid nitrogen until RNA extraction.
Project description:We employed a transgenic strain of a small aquarium fish medaka (Oryzias latipes) that overexpresses a malignant melanoma driver gene. In this model, melanoma develops with 100 % penetrance. Using the medaka malignant melanoma model, we tested whether cisplatin and trametinib are able to suppress the transcriptomic changes induced by the transgene.