Project description:We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe (BA02) microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.
Project description:We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe (BA02) microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments. Black bears sampled during winter hibernation were compared with the animals sampled during summer. Two tissue types, liver and heart, were hybridized on a custom 12,800 cDNA probe nylon membrane microarray platform . Six hibernating and five summer active bears were studied in experiments with liver tissue, six hibernating and five summer active animals were tested with heart tissue.
Project description:Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species.
Project description:Japanese flounder (Paralichthys olivaceus) is an economic important aquaculture fish that was susceptible to Vibrio anguillarum. To fully deciphered the molecular mechanisms underlying flounder host defense against V. anguillarum infection, we perform the micro-transcriptome analysis of founder spleen with and without V. anguillarum infection at 3 time points.
Project description:The 987 probes (Japanese flounder conserved miRNAs and candidates, fish conserved miRNAs, and contro) were hybridized with two stages during Japanese flounder metamorphosis by miRNA microarray. We validated 92 miRNAs using miRNA microarray in the 17 dph and 29 dph of Japanese flounder development, and obtained 66 differertially expressed miRNAs by comparison miRNA expression patterns of the two stages. These results indicate that miRNAs might play key roles in regulating gene expression during Japanese flounder metamorphosis.
Project description:In previous studies, we employed multiple behavior assays, including propensity to feed, simulated trawl capture and escape response, to prove the presence of bold and shy personality in olive flounder. However, the molecular mechanism of the different personality has not been elucidated. In the present study, the transcriptomic profiles of the hindbrain from flounder with distinct personalities were compared. A total of 144 differently expressed genes were identified, including 74 up-regulated and 70 downregulated genes. Genes involved in hypoxia stress were detected in SP flounder, accompanied by down-regulation of ribosomal RNA synthesis. In addition, genes related to calcium signaling pathway, including endothelin, b-Fos, c-Fos and c-Jun were up-regulated in SP flounder. Furthermore, personality-related genes, including UI, CCK, c-Fos showed a significantly higher level in SP flounder compared with BP flounder. GO enrichment analysis indicated that the GO categories “the tight junction pathway” and “lipid transport or localization pathway” are enriched in SP flounder, suggesting that the central nervous system homeostasis would be compromised. Finally, a simple and scalable DNA methylation profiling allows for methylation analysis for different genes. The results found that part of gene expression is negatively related to methylation of promoter. Altogether, identification of the related genes in flounder with different personalities will shed new light to improve critical industry issues related to stress and increase aquaculture production of flounder.