Project description:We sequenced mRNA from 9 liver samples of juvenile largemouth bass (Micropterus salmoides) taken from different lead concentration exposure treatment fish and control fish to investigate the transcriptome and comparative expression profiles of largemouth bass liver undergoing lead exposure.
Project description:This SuperSeries is composed of the following subset Series: GSE38738: High contaminant loads in Lake Apopka mesocosms affect the ovarian transcriptome in largemouth bass [April] GSE38773: High contaminant loads in Lake Apopka mesocosms affect the ovarian transcriptome in largemouth bass [January] Refer to individual Series
Project description:This SuperSeries is composed of the following subset Series: GSE38456: Characterizing gene regulatory networks in the brain of largemouth bass inhabiting rivers containing high levels of methyl-mercury (lab study) GSE38458: Characterizing gene regulatory networks in the brain of largemouth bass inhabiting rivers containing high levels of methyl-mercury (field study) Refer to individual Series
Project description:A novel custom microarray for largemouth bass (Micropterus salmoides) was designed from sequences obtained from a normalized cDNA library using the 454 Life Sciences GS-20 pyrosequencer. The GS-20 yielded in excess of 58 million bases of high-quality sequence. The sequence information was combined with 2,616 reads obtained by traditional suppressive subtractive hybridizations to derive a total of 31,391 unique sequences. Annotation and coding sequences were predicted for these transcripts where possible. 16,350 annotated transcripts were selected as target sequences for the design of the custom largemouth bass oligonucleotide microarray. The microarray was validated by examining the transcriptomic response in male largemouth bass exposed to 17 -oestradiol. Transcriptomic responses were assessed in liver and gonad, and indicated gene expression profiles typical of exposure to oestradiol. The results demonstrate the potential to rapidly create the tools necessary to assess large scale transcriptional responses in non-model species, paving the way for expanded impact of toxicogenomics in ecotoxicology. Keywords: E2 exposure, array validation This experiment tested two organs - liver and gonad from either E2-exposed or control fish, 4 fish (biological replicates) per treament (control and E2).
Project description:A novel custom microarray for largemouth bass (Micropterus salmoides) was designed from sequences obtained from a normalized cDNA library using the 454 Life Sciences GS-20 pyrosequencer. The GS-20 yielded in excess of 58 million bases of high-quality sequence. The sequence information was combined with 2,616 reads obtained by traditional suppressive subtractive hybridizations to derive a total of 31,391 unique sequences. Annotation and coding sequences were predicted for these transcripts where possible. 16,350 annotated transcripts were selected as target sequences for the design of the custom largemouth bass oligonucleotide microarray. The microarray was validated by examining the transcriptomic response in male largemouth bass exposed to 17 -oestradiol. Transcriptomic responses were assessed in liver and gonad, and indicated gene expression profiles typical of exposure to oestradiol. The results demonstrate the potential to rapidly create the tools necessary to assess large scale transcriptional responses in non-model species, paving the way for expanded impact of toxicogenomics in ecotoxicology. Keywords: E2 exposure, array validation
2008-08-01 | GSE10693 | GEO
Project description:The intestinal microbita of largemouth bass fed with high starch
Project description:Male largemouth bass were injected with 25 mg/kg MXC and sacrificed after 48 hours; liver dissected and used for total RNA extraction Keywords: Methoxychlor injection; single injection and time point The organochlorine pesticide methoxychlor (MXC) (1,1,1-trichloro-2,2-bis(p-methoxyphenyl)ethane) has been used increasingly as an insecticide since the banning of DDT, the primary advantage being that MXC is rapidly metabolized and does not show high levels of bioaccumulation in non-target organisms. However, studies have shown that MXC can be metabolized into additional metabolites, such as mono-demethylated 2-(p-hydroxyphenyl)-2-(p-methoxyphenyl)-1,1,1-trichloroethane (OH-MXC) and bis-demethylated 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), both of which are estrogenic in mammals. In addition, there is increased potential for disruptions to normal hepatic physiology (Schlenk et al., 1998; Stuchal et al., 2006). The objectives of the present study were to study the hepatic genomic response in male largemouth bass to an i.p. injection of MXC. We performed a microarray analysis on 25 mg/kg MXC 48 hour injection because there was a significant induction of ERα and ERβb mRNA in the liver which was comparable to a 48 hour 1 mg/kg injection of E2 (previous work done by Blum et al., 2008; Aquat Toxicol. 86(4), 459-469). We chose the liver because of the significant role this tissue plays in detoxification of contaminants and due to the high capacity to produce vitellogenin in response to estrogenic chemicals. We were also interested in comparing the genomic response of MXC to estradiol alone to identify putative candidate genes and pathways that may be specific to MXC and not due to direct estrogenic effects mediated via E2 receptors. Largemouth bass injected with single i.p. with 25 mg/kg methoxychlor; sacrificed 48 days later,liver tissue studied. 4 individual liver samples (control and treatment)
Project description:This study examines the genomic effects of dieldrin in the hypothalamus of largemouth bass. Dieldrin is an insectide and organic pollutant. Largemouth bass fed diedrin for two months once a day ad libitium; 4 biological replicates for each group
Project description:This study used an emerging analytical technology (cDNA microarrays) to assess the potential effects of PFC exposure on largemouth bass in TCMA lakes. Microarrays simultaneously measure the expression of thousands of genes in various tissues from organisms exposed to different environmental conditions. From this large data set, biomarkers (i.e., genes that are expressed in response to an exposure to known stressors) and bioindicators (e.g., suites of genes that correspond to changes in organism health) can be simultaneously measured to clarify the relationship between contaminant exposure and organism health. Based on current scientific literature, we hypothesized that gene expression patterns would be altered in fish exposed to PFCs (as compared with fish from reference lakes), and that the magnitude of these changes would correspond to the concentrations of PFCs present throughout TCMA lakes. Patterns of gene expression in largemouth bass observed across the TCMA lakes corresponded closely with PFC concentration. Concentrations of PFCs in largemouth bass varied significantly across the sampled lakes, where the lowest concentrations were found in Steiger and Upper Prior Lakes and the highest concentrations were found in Calhoun and Twin Lakes. Patterns of gene expression were most different (relative to controls) in fish with the highest PFC tissue concentrations, where fish from Twin and Calhoun Lakes were observed to have between 5437 and 5936 differentially expressed genes in liver and gonad tissues. Although gene expression patterns demonstrated a high degree of correlation with PFC concentrations, microarray data also suggest there are likely additional factors influencing gene expression patterns in largemouth bass in TCMA lakes.