A Dive into the Circadian Clock of Chinook Salmon
Standing
Graduate (Masters)
Type of Proposal
Oral Presentation
Faculty
Faculty of Science
Proposal
Chinook salmon populations inhabiting different latitudes are diverging from another, and the circadian clock is thought to be a contributor in the evolution of distinct latitudinal populations. Like all animals, Chinook salmon have an endogenous molecular clock that regulates their physiology in response to light-dark cycles, which vary with latitude; however, the function of the clock in Chinook salmon has not been studied yet. We piloted an experiment showing that the clock is transcriptionally active in the liver, heart, and intestine of Chinook salmon parr reared in the FREC in LaSalle in 2017. In summer 2018, we expanded the project to study a more homogenous Chinook salmon population at YIAL in British Columbia. The fish were reared under different light conditions and feeding times to explore the effect of light and feeding time on the clock and its downstream targets. We collected samples from the intestine, liver, brain, heart and muscle. The expression of the genes that make up the clock will be assayed in all these tissues to determine clock activity. In the intestine, a Taqman OpenArray gene chip will be designed to assay the expression of genes involved in nutrient absorption, digestion, hormonal appetite regulation, inflammation, and intestinal regeneration. These genes show rhythmic activity in various species, thus it will be important to study changes in their expression levels throughout the day and across the various lighting and feeding conditions. This research will explore whether clock function is a factor in the evolution of this threatened species by comparing clock output under two photoperiod conditions that resemble those of southern and northern habitats. By determining when appetite and growth are up-regulated, this will also help identify the optimal rearing conditions to improve yields in aquaculture.
Grand Challenges
Healthy Great Lakes
A Dive into the Circadian Clock of Chinook Salmon
Chinook salmon populations inhabiting different latitudes are diverging from another, and the circadian clock is thought to be a contributor in the evolution of distinct latitudinal populations. Like all animals, Chinook salmon have an endogenous molecular clock that regulates their physiology in response to light-dark cycles, which vary with latitude; however, the function of the clock in Chinook salmon has not been studied yet. We piloted an experiment showing that the clock is transcriptionally active in the liver, heart, and intestine of Chinook salmon parr reared in the FREC in LaSalle in 2017. In summer 2018, we expanded the project to study a more homogenous Chinook salmon population at YIAL in British Columbia. The fish were reared under different light conditions and feeding times to explore the effect of light and feeding time on the clock and its downstream targets. We collected samples from the intestine, liver, brain, heart and muscle. The expression of the genes that make up the clock will be assayed in all these tissues to determine clock activity. In the intestine, a Taqman OpenArray gene chip will be designed to assay the expression of genes involved in nutrient absorption, digestion, hormonal appetite regulation, inflammation, and intestinal regeneration. These genes show rhythmic activity in various species, thus it will be important to study changes in their expression levels throughout the day and across the various lighting and feeding conditions. This research will explore whether clock function is a factor in the evolution of this threatened species by comparing clock output under two photoperiod conditions that resemble those of southern and northern habitats. By determining when appetite and growth are up-regulated, this will also help identify the optimal rearing conditions to improve yields in aquaculture.