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:Egg quality is an important aspect in rainbow trout farming. Post-ovulatory aging is one of the most important factors affecting egg quality. MicroRNAs (miRNAs) are the major regulators in various biological processes and their expression profiles could serve as reliable biomarkers for various pathological and physiological conditions. Egg samples from 32 females on day 1, day 7, and day 14 post-ovulation (D1PO, D7PO and D14PO), which had the fertilization rates of 91.8%, 73.4% and less than 50%, respectively, were collected and small RNAs isolated from these samples were subjected to deep sequencing using the Illumina platform. Six miRNAs were found to be differentially expressed between D1PO and D14PO eggs. GO analysis of the target genes of the 6 miRNAs that were down-regulated in D14PO eggs revealed significantly enriched GO terms that are related to stress response, cell death, DNA damage, ATP generation, signal transduction and transcription regulation. Examination of small RNA populations in eggs of different qualities caused by post-ovulatory aging.
Project description:This SuperSeries is composed of the SubSeries listed below. Growth in fishes is a complex trait, controlled by both genetic and environmental factors, that impacts many components of fitness. Gene expression studies may lead to the identification of candidate genes for growth and microarrays offer the opportunity to examine the expression of thousands of genes simultaneously. Gene expression differences in the liver and white muscle were examined in normally growing, 15 month-old, large and small size-selected rainbow trout (Oncorhynchus mykiss) derived from two different seasonal spawning groups (Sept. and Dec.). Examination of the gene expression differences in both liver and white muscle tissue allowed us to assess the seasonal influences upon gene expression patterns that occur in this species, and facilitated the identification of genes that may possess similar expression patterns regardless of seasonal effects. The analysis of global gene expression in large and small fish reared under standard conditions provides an understanding of typical growth patterns that may be observed in this species. The identification of candidate genes by this study may provide insight into the mechanisms of growth in fishes and may help to identify candidate genes for growth.
Project description:We identified that the adiponectin gene expression in rainbow trout muscle decreased by restrected feeding. In order to identify the genes differently expressed by the same treatment, micrarray analysis was conducted Fish were fed ad libitum once a week (RF, restricted feed group) or fed ad libitum twice per day (control). After 1 month, the muscle was desected from 4 individuals from each group.
Project description:To date, little is known about the proteomic changes at the portals of entry in rainbow trout after infection with the myxozoans, Myxobolus cerebralis, and Tetracapsuloides bryosalmonae the causative agents of whirling disease and proliferative kidney disease, respectively. Therefore, the aim of this study was to provide the first proteomic profiles of the host in the search for evasion strategies against single and coinfection with M. cerebralis and T. bryosalmonae. One group of fish was initially infected with M. cerebralis and another group with T. bryosalmonae. After 30 days, half of the fish in each group were co-infected with the other parasite. Using a quantitative proteomic approach, we investigated proteomic changes in the caudal fins and gills of rainbow trout before and after co-infection. In the caudal fins, 16 proteins were differentially regulated post exposure to M. cerebralis, whereas 27 proteins were differentially modulated in the gills of the infected rainbow trout post exposure to T. bryosalmonae. After co-infection, 4 proteins involved in parasite recognition and the regulation of host immune responses were differentially modulated between the groups in the caudal fin. In the gills, 11 proteins involved in parasite recognition and host immunity, including 4 myxozoan proteins predicted to be virulence factors, were differentially modulated. The results of this study increase our knowledge on rainbow trout co-infections by myxozoan parasites and rainbow trout immune responses against myxozoa at the portals of entry, supporting a better understanding of these host-parasite interactions.
Project description:In mammals, increasing data suggests that there exists a complex and bi-directional relationship between thyroid and immune systems. However the existence of such interactions in fish is unknown. Here, we administered the biologically active hormone 3.3�.5-triiodo-L-thyronine (T3) and the anti-thyroid drug, propilthiouracil (PTU) to juvenile rainbow trout and examined the head kidney expression profile with a custom-made microarray enriched in immune-related genes. A seven day-experiment was performed. Fish were divided in 3 groups. First group received 20 µg/g fish feed of T3; second group received 5000 µg/g fish feed of PTU; third group served as control. After 7 days orally administering T3 or PTU, differentially expressed transcript levels from selected immune-related rainbow trout genes were studied in head kidney. Three groups were studied (T3-treated, PTU treated and control), each group having 4 biological replicates (each replicate consisting of 2 pooled fish).
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:Whirling disease, caused by the pathogen Myxobolus cerebralis, afflicts several salmonid species. Rainbow trout are particularly susceptible and suffer high mortality rates. The disease is persistent and spreading in hatcheries and natural waters of several countries, including the U.S., and the economic losses associated with whirling disease have been extremely large. In this study, gene expression profiling was conducted for resistant and susceptible rainbow trout strains following pathogen exposure with the primary objective of identifying specific genes associated with whirling disease resistance. Several genes were significantly up-regulated in skin following pathogen exposure for both the resistant Hofer and susceptible Trout Lodge rainbow trout strains. For both strains, response to infection appears to be associated with the interferon system. Metallothionein is differentially expressed between the resistant and susceptible strains and is a good candidate for future studies due to its diverse functional roles in inflammation and immune response. The present study has provided the first examination into the genetic basis underlying rainbow trout’s immune response and resistance to the whirling disease pathogen. The identified genes have allowed us to gain initial insight into the molecular mechanisms associated with a salmonid host’s immune response and resistance to whirling disease infection. Keywords: Disease state comparison. 1st comparison: exposed vs control. 2nd comparison: resistant vs susceptible strains Resistant (Hofer) and susceptible (Trout Lodge) rainbow trout strains were exposed to 2,000 triactinomyxons (whirling disease pathogen) per fish. Unexposed controls for each strain were treated identically to exposed other than their lack of pathogen exposure. After twenty-four hours, caudal fin tissue was collected for RNA extraction. Amplified RNA was competitively hybridized (exposed versus control) for each strain. Four biological replicates were used for each experimental condition and a balanced block design was incorporated.
Project description:We describe here transcripts induced after intraperitoneal injection of rainbow trout with 2 different viruses, both belonging to strain 23.75 of viral hemorrhagic septicemia virus (VHSV): a deleted Nv gene (dNV) virus and a wild type (wt) virus. Two days after infection, differentially expressed transcript levels from selected immune-related trout genes were studied in internal organs (spleen and head kidney). Fishes were divided in two groups (3 fishes per group). The first group was intraperitoneally injected with 100000 pfu per trout of dNV VHSV, while the second group was injected with 100000 pfu/trout of wt VHSV. All fishes were sacrificed two days post infection.
Project description:The aim of present study is to identify and quantify proteins involved in the events of fertilization and early embryo development using a label-free protein quantification method in rainbow trout (Oncorhynchus mykiss) as an economically important fish species in aquaculture.