Project description:Aquaculture is one of the fastest growing food production sectors in the world and further expansion is expected throughout the 21st century. However, climate change is threatening the development of the sector and action is needed to prepare the industry for the coming challenges. Using downscaled temperature projections based on the Intergovernmental Panel on Climate Change (IPCC) climate projection (Shared Socioeconomic Pathway, SSP2-4.5), we analysed potential future temperatures at a selected Atlantic cod (Gadus morhua L.) farm site in Northern Norway. Results showed that the farming area may experience increased temperatures the next 10–15 years, including more days with temperatures above 17°C. Based on the predicted future conditions, we designed a study with Atlantic cod (Gadus morhua L.) to evaluate effects from high temperature alone and in combination with Fransicella noatunensis infection. Fish were kept at 12°C and 17°C for eight weeks and samples of skin and spleen collected at different timepoints were analysed with transcriptomics, histology, scanning electron microscopy and immunohistochemistry.
Project description:The methylome and transcriptome signatures following exercise that are physiologically and metabolically relevant to sporting contexts such as team sports or health prescription scenarios (e.g. high intensity interval training/HIIT) has not been investigated. To explore this, we performed two different sport/exercise relevant high-intensity running protocols in 5 male sport team members using a repeated measures design of: 1) Change of direction (COD) versus; 2) straight line (ST) exercise with a wash-out period of at least 2 weeks between trials. Skeletal muscle biopsies collected from the vastus lateralis 30 minutes and 24 hours post exercise, were assayed using 850K methylation arrays and a comparative analysis with recent (subject-unmatched) sprint and acute aerobic exercise meta-analysis transcriptomes was performed. Despite COD and ST exercise being matched for classically defined intensity measures (speed x distance and number of accelerations/decelerations), COD exercise elicited greater movement (GPS-Playerload), physiological (HR), metabolic (lactate) as well as central and peripheral (differential RPE) measures compared with ST exercise, suggesting COD exercise evoked a higher exercise intensity. The exercise response alone across both conditions evoked extensive alterations in the methylome 30 mins and 24 hrs post exercise, particularly in MAPK, AMPK and axon guidance pathways. COD evoked a considerably greater hypomethylated signature across the genome compared with ST exercise, particularly at 30 minutes post exercise, enriched in: Protein binding, MAPK, AMPK, insulin, and axon guidance pathways. Comparative methylome analysis with sprint running transcriptomes identified considerable overlap, with 49% of genes that were altered at the expression level also differentially methylated after COD exercise. After differential methylated region analysis, we observed that VEGFA and its downstream nuclear transcription factor, NR4A1 had enriched hypomethylation within their promoter regions. VEGFA and NR4A1 were also significantly upregulated in the sprint transcriptome and meta-analysis of exercise transcriptomes. We confirmed increased gene expression of VEGFA, and considerably larger increases in the expression of canonical metabolic genes, PPARGC1A (that encodes PGC1-α) and NR4A3 in COD vs. ST exercise. Overall, we demonstrate that increased physiological/metabolic load via change of direction exercise in human skeletal muscle evokes considerable epigenetic modifications that are associated with changes in expression of genes responsible for adaptation to exercise.
Project description:Methylmercury (MeHg) is a highly toxic environmental pollutant. To understand the mechanisms of toxicity of the compound and possibly to discover new biomarkers for environmental monitoring, we have conducted toxicogenomics studies. We designed 126k-cod-oligonucleotide arrays and performed genome-wide gene expression assays in liver samples from juvenile cod treated with MeHg (0.5 and 2 mg/kg body weight). Microarray analysis showed MeHg differentially regulated hundreds of genes. Gene Ontology and pathway analyses of differentially regulated genes revealed that MeHg modulated mainly genes involved in immune response, oxidative stress response, tissue remodelling, and energy pathways such as lipid, carbohydrate and amino acid metabolism. The results provide insights into the mechanisms of toxicity of MeHg and provide candidate biomarkers of exposure to MeHg for further evaluation.
Project description:Background: In coeliac disease (CoD), the role of B cells has mainly been considered to be production of antibodies. The functional role of B cells has not been analysed extensively in CoD. Methods: We conducted a study to characterize gene expression in B cells from children developing CoD early in life using samples collected before and at the diagnosis of the disease. Blood samples were collected from children at risk at 12, 18, 24 and 36 months of age. RNA from peripheral blood CD19+ cells was sequenced and differential gene expression was analysed using R package Limma. Findings: Overall, we found one gene, HNRNPL, modestly downregulated in all patients (logFC -0·7; q=0·09), and several others downregulated in those diagnosed with CoD already by the age of 2 years. Interpretation: The data highlight the role of B-cells in CoD development. The role of HNRPL in suppressing enteroviral replication suggests that the predisposing factor for both CoD and enteroviral infections is the low level of HNRNPL expression.
Project description:Fish in use in aquaculture display large variation in gamete biology. To reach better understanding around this issue, this study aims at identifying if “egg life history traits” can be hidden in egg transcriptomes. To pursue this, salmon and cod eggs were selected due to their largely differencing phenotypes (size, robustness, fresh/marine). An oligo microarray analysis was performed on ovulated eggs from cod (~23 000 genes, n=8) and salmon (~44 000 genes, n=7). The arrays were normalized to a similar spectrum for both arrays. Both arrays were re-annotated based on official gene symbol to retrieve an orthologous KEGG annotation, in salmon and cod arrays this represented 14009 and 7437 genes respectively. The probe linked to the highest gene expression for that particular KEGG annotation was used to compare expression between species. Differential expression was calculated for genes that had an annotation with score > 300, resulting in a total of 2354 KEGG annotations (genes) being differently expressed between the species. The most differentially expressed genes in salmon and cod (FD≥2), were used to reveal pathways that were overrepresented in the eggs of each species. This analysis revealed that immune, signal transduction, and excretory related pathways were overrepresented in salmon compared to cod. The most overrepresented pathways in cod were related to regulation of genetic information processing and metabolism. To conclude this analysis clearly point at some distinct transcriptome repertoires for cod and salmon and that these differences may explain some of the species-specific biological features for salmon and cod eggs.
Project description:Lipid metabolism is essential in maintaining energy homeostasis in multicellular organisms. In vertebrates, a group of nuclear receptor transcription factors named peroxisome proliferator-activated receptors (PPARs, NR1C) regulate the expression of many genes involved in these processes. We have recently cloned the four Ppars in Atlantic cod (Gadus morhua), including Ppara1 and Ppara2, Pparb/d, and Pparg, and studied their tissue specific transcription and ligand activation characteristics. However, the downstream regulative role of Ppars in cod lipid metabolism is not well understood or described. In this study, activation of Atlantic cod Ppar by the fibrate drug WY-14,643 (pirinixic acid) and the performance enhancing drug GW501516 (Cardarine) were first studied using ligand-binding luciferase reporter assays in vitro. Based on the agonist activities found in vitro, juvenile Atlantic cod was injected twice over four days with WY-14,643 and GW501516 in vivo, and sampled seven days after the last injection. Using multiple omics methods, including RNA sequencing, quantitative proteomics, and lipidomics, liver and plasma samples from male cod were analyzed. The resulting multi-omics dataset provides novel insights into the systemic regulation of lipid metabolism in Atlantic cod.
Project description:The aim of the exposure was to study the effects of activation of peroxisome proliferator-activated receptors (PPARs) in Atlantic cod (Gadus morhua), by injecting the fish with the compounds WY-14,643 and GW501516. Using luciferase reporter assay in vitro, we have shown that WY-14,643 activate Atlantic cod Ppara1 and Ppara2, while GW501516 activate Ppara1, Ppara2, and Pparb. The experimental set-up was as follows: Immature cod were injected at day 0 and day 4 with either high dose (40 mg/kg WY-14,643 and 4.0 mg/kg GW501516), low dose (4.0 mg/kg WY-14,643 and 0.4 mg/kg GW501516), or solvent control (10 % DMSO, 90 % teleost saline (2.41 mM KCl, 133.5 mM NaCl, 1.5 mM CaCl2, 0.79 mM MgSO4, 1 mM NaHCO3, 0.5 mM Na2HPO4)). At day 11, liver samples were collected from 9-12 male fish from each group (total of 50 samples). Total RNA was isolated from 50 mg of each sample using TRI reagent (Sigma), and 0.4 μg RNA were sequenced at the Genomics Core Facility at the University of Bergen on Illumina HiSeq 4000 (Illumina, Inc., San Diego, CA, USA).