Project description:The aim of this sequencing experiment was to make available tissue expression panels for selected fish species for comparative expression studies between the species. Tissue samples were collected for zebrafish (Danio rerio), medaka (Oryzias latipes), and rainbow trout (Oncorhynchus mykiss). Tissue types included liver, skin, muscle, heart, gut, gill, eye, brain for all three species, with additionally pyloric caeca, kidney, head kidney, and spleen for rainbow trout. Only liver samples were taken in replicate of four or three for rainbow trout. All fish were raised under standard rearing conditions for the species. Total RNA was extracted from the tissue samples and paired‐end sequencing of sample libraries was completed on an Illumina HiSeq 2500 with 125‐bp reads. Processed count tables per species as raw counts, FPKM, or TPM, were generated from read alignment to the Ensembl genomes of the respective species using STAR and gene level counting using RSEM and Ensembl gene annotation.
Project description:Background: Rainbow trout (Oncorhynchus mykiss) is a salmonid species with a complex life-history. Wild populations are naturally divided into freshwater residents and sea-run migrants. Migrants undergo an energy-demanding adaptation for life in seawater, known as smoltification, while freshwater residents display these changes in an attenuated magnitude and rate. Despite this, in seawater rainbow trout farming all animals are transferred to seawater. Under these circumstances, weeks after seawater transfer, a significant portion of the fish die (around 10%) or experience growth stunting (GS; around 10%), which represents an important profitability and welfare issue. The underlying causes leading to GS in seawater-transferred rainbow trout remain unknown. In this study, we aimed at characterising the GS phenotype in seawater-transferred rainbow trout using untargeted and targeted approaches. To this end, the liver proteome (LC-MS/MS) and lipidome (LC-MS) of GS and fast-growing phenotypes were profiled to identify molecules and processes that are characteristic of the GS phenotype. Moreover, the transcription, abundance or activity of key proteins and hormones related to osmoregulation (Gill Na+, K+–ATPase activity), growth (plasma IGF-I, and liver igf1, igfbp1b, ghr1 and ctsl) and stress (plasma cortisol) were measured using targeted approaches. Results: No differences in Gill Na+, K+–ATPase activity and plasma cortisol were detected between the two groups. However, a significant downregulation in plasma IGF-I and liver igf1 transcription pointed at this growth factor as an important pathomechanism for GS. Changes in the liver proteome revealed reactive-oxygen-species-mediated endoplasmic reticulum stress as a key mechanism underlying the GS phenotype. From the lipidomic analysis, key observations include a reduction in triacylglycerols and elevated amounts of cardiolipins, a characteristic lipid class associated with oxidative stress, in GS phenotype. Conclusion: While the triggers to the activation of endoplasmic reticulum stress are still unknown, data from this study point towards either an unresolved infection or a nutritional deficiency as underlying drivers of this phenotype.
Project description:Transcriptional profiling of rainbow trout liver cells comparing liver cells from small fish with liver cells from large fish at two time periods.
Project description:Transcriptional profiling of rainbow trout muscle cells comparing muscle cells from small fish with muscle cells from large fish at two time periods.
Project description:Different gene expression profiles between normal and thermally selected strains of rainbow trout, Oncorhynchus mykiss, as revealed by comprehensive transcriptome analysis
Project description:Rainbow trout is a typical cold-water fish, with the intensification of global warming, high temperatures severely restrict the development of aquaculture in summer. Understanding the molecular regulation mechanisms of rainbow trout in response to heat stress will be salutary to alleviate heat stress-related damage. In the present study, we performed transcriptome analysis of liver tissues in rainbow trout under heat stress (24℃) and control (18℃) conditions to identify induced lncRNAs and pathways by heat stress. More than 658 million clean reads and 5,916 lncRNAs were identified from six liver libraries. A total of 927 novel lncRNAs were generated and 428 differentially expressed lncRNAs were screened through stringent thresholds. The RNA-seq results were verified by RT-qPCR. In addition, the regulatory network of important functional lncRNA-mRNA were constructed. GO and KEGG enrichment analysis of target gene of differentially expressed lncRNAs were performed. Many target genes involved in maintaining homeostasis or adapting to stress and stimuli were highly induced under heat stress. Several important regulatory pathways were involved in heat stress, including thyroid hormone signaling pathway, PI3K-Akt signaling pathway, estrogen signaling pathway, etc. This result broadens our understanding of lncRNA associated with heat stress and provides new insights into lncRNA-mediated regulation of rainbow trout heat stress.
Project description:The hypoxia frequently occurs in natural aquatic systems and aquaculture environment due to the natural reasons and human factors such as extreme climate, high density farming, environmental pollution and global warming, which have gradually become a huge threat to aquatic ecosystem functions and aquatic organism survival, causing serious ecological damage and enormous economic losses. Rainbow trout (Oncorhynchus mykiss), as a hypoxia-sensitive fish species, is a good model to study hypoxia stress. The molecular regulation and oxidative stress of rainbow trout still remains unknown in response to environmental hypoxia and reoxygenation stress. In this study, the transcriptome and biochemical indexes of rainbow trout liver in response to hypoxia for different durations were analyzed to highlight the changes in the molecular regulation and oxidative stress.
Project description:Rainbow trout (1000 fish) was exposed to the bacterial pathogen F. psychrophilum by simple bath challenge without any pre-treatment with hydrogen peroxide. Samples (fin clip for Affymetrix QTL analysis) were taken from 167 moribund fish during the course of infection. When mortality/morbidity ended (day 40) we euthanized a total of 197 specimens of the remaining fish and took samples for DNA (QTL analysis) and assigned the status: Survivor. For gene expression analysis we took samples from gill, spleen and liver between day 11 and 15 from fish with clinical signs (CS) and no clinical signs (NCS), whereas samples from survivors were taken at day 40.
Project description:Transcriptional profiling of rainbow trout liver and muscle cells comparing small fish with large fish within a population of neomale offspring.