Project description:Genome-wide microarray analysis of the effects of swim-training on zebrafish larval development. Zebrafish were subjected to swim-training from 5 days post fertilization (dpf) until 10 dpf. Subsequently, we performed a genome-wide microarray analysis of trained and control fish at 10 dpf. The goal of the project was to investigate the effects of swim-training on the gene expression level during zebrafish larval development
Project description:Genome-wide microarray analysis of the effects of swim-training on caudal fin development in zebrafish larvae. Zebrafish were subjected to swim-training from 5 days post fertilization (dpf) until 10 dpf. Subsequently, we performed a genome-wide microarray analysis on the caudal fins of control and trained fish at 10 dpf. The goal of the project was to investigate the effects of swim-training on the gene expression level during caudal fin development in zebrafish larvae.
Project description:Genome-wide microarray analysis of the effects of swim-training on zebrafish larval development. Zebrafish were subjected to swim-training from 5 days post fertilization (dpf) until 10 dpf. Subsequently, we performed a genome-wide microarray analysis of trained and control fish at 10 dpf. The goal of the project was to investigate the effects of swim-training on the gene expression level during zebrafish larval development Two-condition experiment: control vs trained fish. RNA was isolated from 10 control fish and from 10 trained fish. Subsequently, each sample was labeled with Cy3 and Cy5 in order to correct for dye bias. Control-Cy3 and Trained-Cy5 were hybridized on array 1 and Trained-Cy5 and Control-Cy3 were hybridized on array 2.
Project description:Genome-wide microarray analysis of the effects of swim-training on caudal fin development in zebrafish larvae. Zebrafish were subjected to swim-training from 5 days post fertilization (dpf) until 10 dpf. Subsequently, we performed a genome-wide microarray analysis on the caudal fins of control and trained fish at 10 dpf. The goal of the project was to investigate the effects of swim-training on the gene expression level during caudal fin development in zebrafish larvae. Two-condition experiment: control vs trained fish. RNA was isolated from pooled caudal fins of 15 control fish (in duplo: pooled control samples (C2 and C3)) and of 15 trained fish (in duplo: pooled trained samples( T2 and T3)). Subsequently, each pooled RNA sample of control and trained caudal fins was labeled with Cy3 and Cy5 in order to correct for dye bias. We included a technical replicate of the labeled C2 and T2 samples.
Project description:Forced sustained swimming exercise at optimal speed enhances growth in many fish species, particularly through hypertrophy of the white skeletal muscle. The exact mechanism of this effect has not been resolved yet. To explore the mechanism, we first subjected wild-type zebrafish to an exercise protocol validated for exercise-enhanced growth, and showed that exercised zebrafish, which indeed showed enhanced growth, had higher cortisol levels than the non-exercised controls. A central role was therefore hypothesized for the steroid hormone cortisol acting through the Glucocorticoid receptor (Gr). Second, we subjected wild-type zebrafish and zebrafish with a mutant Gr to exercise at optimal, suboptimal and super-optimal speeds and compared them with non-exercised controls. Exercised zebrafish showed growth enhancement at all speeds, with highest growth at optimal speeds. In the Gr mutant fish, exercise resulted in growth enhancement similar to wild-type zebrafish, indicating that cortisol cannot be considered as a main determinant of exercise-enhanced growth. Finally, the transcriptome of white skeletal muscle tissue was analysed by RNA sequencing. The results of this analysis showed that in the muscle tissue of Gr mutant fish a lower number of genes is regulated by exercise than in wild-type fish (183 versus 351). A cluster of 36 genes was regulated by exercise in both wild-type and mutant fish. In this cluster, genes involved in transcriptional regulation and protein ubiquitination were overrepresented. Since growth was enhanced similarly in both wild-type fish and mutants, these processes may play an important role in exercise-enhanced growth.
Project description:Low temperatures may cause severe growth inhibition and mortality in fish. In order to understand the mechanism of cold tolerance, a transgenic zebrafish Tg (smyd1:m3ck) model was established to study the effect of energy homeostasis during cold stress. The muscle-specific promoter Smyd1 was used to express the carp muscle form III of creatine kinase (M3-CK), which maintained enzymatic activity at a relatively low temperature, in zebrafish skeletal muscle. In situ hybridization showed that M3-CK was expressed strongly in the skeletal muscle. When exposed to 13°C, Tg (smyd1:m3ck) fish maintained their swimming behavior, while the wild-type could not. Energy measurements showed that the concentration of ATP increased in Tg (smyd1:m3ck) versus wild-type fish at 28°C. After 2 h at 13°C, ATP concentrations were 2.16-fold higher in Tg (smyd1:m3ck) than in wild-type (P < 0.05). At 13°C, the ATP concentration in Tg (smyd1:m3ck) fish and wild-type fish was 63.3% and 20.0%, respectively, of that in wild-type fish at 28°C. Microarray analysis revealed differential expression of 1249 transcripts in Tg (smyd1:m3ck) versus wild-type fish under cold stress. Biological processes that were significantly overrepresented in this group included circadian rhythm, energy metabolism, lipid transport, and metabolism. These results are clues to understanding the mechanisms underlying temperature acclimation in fish.
Project description:The exon junction complex (EJC) is composed of three core proteins Rbm8a, Magoh and Eif4a3 and is thought to play a role in several post-transcriptional processes. In this study we focus on understanding the role of EJC in zebrafish development. We identified transcriptome-wide binding sites of EJC in zebrafish via RNA:protein immunoprecipitation followed by deep sequencing (RIP-Seq). We find that, as in human cells, zebrafish EJC is deposited about 24 nts upstream of exon-exon junctions. We also identify transcripts regulated by Rbm8a and Magoh in zebrafish embryos using whole embryo RNA-seq from rbm8a mutant, magoh mutant and wild-type sibling embryos. This study shows that nonsense mediated mRNA decay is dysregulated in zebrafish EJC mutants.
Project description:Background: Obesity is a worldwide public health problem with increasing prevalence and affects 80% of diabetes mellitus type 2 cases. Zebrafish (Danio rerio) are an established model organism for studying obesity and diabetes including diabetic microvascular complications. We aimed to determine whether physical activity is an appropriate tool to examine training effects in zebrafish and to analyse metabolic and transcriptional processes in trained zebrafish. Methods: A 2- and 8-weeks experimental training phase protocol with adult zebrafish in a swim tunnel system was established. We examined zebrafish basic characteristics before and after training such as body weight, body length and maximum speed and considered overfeeding as an additional parameter in the 8-weeks training protocol. Ultimately, the effects of training and overfeeding on blood glucose, muscle core metabolism and liver gene expression using RNA-Seq were investigated. Results: Zebrafish maximum speed was correlated with body length and was significantly increased after 2 weeks of training. Maximum swim speed further increased after 8 weeks of training in both the normalfed and the overfed groups, but training was found not to be sufficient in preventing weight gain in overfed fish. Metabolome and transcriptome profiling in trained fish exhibited increased blood glucose levels in the short-term and upregulated energy supply pathways in the long-term. Conclusion: Swim training is a valuable tool to study effects of physical activity in zebrafish, which is accompanied by metabolic and transcriptional adaptations.