Project description:Chinook salmon (Oncorhynchus tshawytscha) display the greatest variability of return times to freshwater of all Pacific salmon. Populations return to freshwater for spawning at many different times of year, resulting in segregated populations that may use differing molecular pathways for these large behavioral and physiological differences. Using a population of Chinook from California’s Central Valley, we sought to generate novel expressed sequences using Long Serial Analysis of Gene Expression (LongSAGE). We constructed three LongSAGE libraries from brains of samples caught in the spring and fall in freshwater and from the ocean. Using cDNA libraries from Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss), we were able to assign 59% of putatively differentially expressed tags to genes. Additionally, we tested the expression levels of seven genes, indicated by LongSAGE to be putatively differentially expressed between the fall and spring, and found none significantly differentially expressed. This study is the first to apply LongSAGE to salmon and provides a framework for conducting future research on gene expression differences between Chinook salmon of different populations, as well as underlying mechanisms of differing physiology and behavior. Keywords: seasonal difference
Project description:Chinook salmon (Oncorhynchus tshawytscha) display the greatest variability of return times to freshwater of all Pacific salmon. Populations return to freshwater for spawning at many different times of year, resulting in segregated populations that may use differing molecular pathways for these large behavioral and physiological differences. Using a population of Chinook from California’s Central Valley, we sought to generate novel expressed sequences using Long Serial Analysis of Gene Expression (LongSAGE). We constructed three LongSAGE libraries from brains of samples caught in the spring and fall in freshwater and from the ocean. Using cDNA libraries from Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss), we were able to assign 59% of putatively differentially expressed tags to genes. Additionally, we tested the expression levels of seven genes, indicated by LongSAGE to be putatively differentially expressed between the fall and spring, and found none significantly differentially expressed. This study is the first to apply LongSAGE to salmon and provides a framework for conducting future research on gene expression differences between Chinook salmon of different populations, as well as underlying mechanisms of differing physiology and behavior. Keywords: seasonal difference Single individuals were used to construct each LongSAGE library. The fall, spring and ocean samples were then compared between each other and examined for differences in the number of tags observed.
Project description:Understanding the molecular mechanisms of feed efficiency is an important step toward sustainability of salmonids aquaculture. In this study, the liver and white muscle proteomes of efficient (EFF) and inefficient (INEFF) Chinook salmon (Oncorhynchus tshawytscha) farmed in sea water were investigated by liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach. In total, 2,746 liver and 702 white muscle quantified proteins were compared between 21 EFF and 22 INEFF fish. Protein synthesis was enriched in both liver and white muscle of the EFF group while conversely, pathways related to protein degradation (amino acid catabolism and proteolysis, respectively) were the most affected processes in the liver and white muscle of INEFF fish. The SOM in the INEFF group was significantly higher than EFF fish showing INEFF fish probably was the dominant group. The INEFF group (dominant) suffered stress and shifted to consume energy through protein catabolism. As the first study, the results provide a preliminary picture of the fundamental molecular landscape of feed efficiency in Chinook salmon farmed in sea water
