Project description:Background: Yellow catfish (Pelteobagrus fulvidraco) is one of the important aquaculture species in China. In recent years, due to the high breeding density, the increasing frequency of feeding, and the excessive addition of feed fat, the excessive deposition of body fat in cultured yellow catfish has become more frequent. MicroRNAs (miRNAs) are an important gene expression regulatory signal molecule that regulates liver fat synthesis and transport and play an important role in fat deposition. However, there is a little research on the mechanism of fatty liver caused by excessive deposition of liver fat. Results: After 60 days of high-fat stress, the growth and feed conversion rate of hybrid yellow catfish (Pelteobagrus fuIvidraco♀×P. vachelli♂) were significantly inhibited, and hepatosomatic index, viscerosomatic index, hepatic triglyceride and cholesterol, and red lipid droplets in liver tissues were increased. Through high-throughput sequencing, we constructed miRNA libraries of high-fat stress at 60d, identified 346 conserved miRNAs and 410 novel miRNAs, among which 13 differentially expressed miRNAs were screened between high-fat diet group and normal-fat diet group. Also, we constructed mRNA transcriptome libraries after high-fat stress. Potential target genes for differentially expressed miRNAs were identified by bioinformatics analysis. Seven miRNA-mRNA pairs were screened. The expression of differential miRNA and mRNA and potential binding sites were analyzed by qRT-PCR and dual luciferase assay. Hybrid yellow catfish could promote the oxidative degradation of liver glucose, reduce fatty acid peroxidation, regulate antioxidant enzyme activity and response of immune and inflammatory to relieve fat deposition and liver stress. Conclusions: The disorders of fat metabolism in liver not only result in feed wastage, increase metabolic burden of yellow catfish, but also cause immune function damage, resulting in a variety of nutritional diseases. The development of this study is to understand the molecular mechanism of hepatic fat deposition in yellow catfish. It has important biological significance for improving protection of liver against stress and healthy culture.
Project description:Transport stress is a big threat to most teleost fish during production practice, causing mass loss to the aquaculture industry. Fish gills are mucosa-associated lymphoid tissue that directly contacted with water, which is the good choice to study the mechanism of transport stress. Gills transcriptome results revealed 1551 differentially expressed genes (744 up-regulated and 807 down- regulated) between the control and 16h transportation groups. The top 10 enriched KEGG pathways are all immune-related. After qRT-PCR validation, we found that the toll-like receptors and nod-like receptors signaling pathways mediate the gill’s immune response to transport stress: tlr5, tnfɑ, hsp90ɑ, il-1ß and map2k4 were significantly up-regulated and arrdc2 was significantly down-regulated under transport stress. These results suggested that the transport stress altered innate immunity responses and induced metabolic changes in gills of hybrid yellow catfish. In conclusion, the results provide new perspectives on immune response in yellow catfish against transport stress and provide the possibility of mining resistance genes for future optimize transportation plan.
Project description:Hypoxia is an important environmental stressor in aquatic ecosystems, with increasingly impacts on global biodiversity. Yellow catfish is an economically important farmed fish in China, which has increased dramatically. We investigated the response of hybrid yellow catfish to hypoxia under experimental conditions and focused on the analysis of the differential expression patterns of specific genes associated with hypoxia response by RNA-seq and qPCR analysis. A total of 1556 genes were captured significantly differentially expressed, and were categorized into immune response and energy metabolism. Functional enrichment analysis revealed the NLR signaling pathway play pivotal roles in hypoxia tolerance and resistance. Our study provides important insights into the physiological acclimation, immune response and defense activity of hybrid yellow catfish under hypoxia challenge.
Project description:In this study, we used next-generation sequencing technologies and tandem mass tags to characterize mRNA-seq, miRNA-seq and proteomic of Pelteobagrus fulvidraco, P. vachelli and hybrid yellow catfish Huangyou-1 (P. fulvidraco female×P. vachelli male) livers and in doing so, offer deeper insight into the transcriptional and protein changes in heterosis uncovers key roles for miRNAs.
Project description:In this study, we used next-generation sequencing technologies and tandem mass tags to characterize mRNA-seq, miRNA-seq and proteomic of Pelteobagrus fulvidraco, P. vachelli and hybrid yellow catfish Huangyou-1 (P. fulvidraco female ×P. vachelli male) livers and in doing so, offer deeper insight into the transcriptional and protein changes in heterosis uncovers key roles for miRNAs.