Data from: Life-stage associated remodeling of lipid metabolism regulation in Atlantic salmon

Atlantic salmon migrates from rivers to sea to feed, grow and develop
gonads before returning to spawn in freshwater. The transition to marine
habitats is associated with dramatic changes in the environment, including
water salinity, exposure to pathogens, and shift in dietary lipid
availability. Many anticipatory changes in physiology occur before
migration to sea, but little is known about the molecular nature of these
changes. Here we use a long term feeding experiment to study
transcriptional regulation of lipid metabolism in Atlantic salmon gut and
liver in both fresh- and saltwater. We find that lipid metabolism is
highly plastic in response to differences in dietary lipid composition in
freshwater, but then undergoes a marked shift when salmon transitions to
the marine life-stage. Expression of genes in liver relating to
lipogenesis and lipid transport decrease overall and become less
responsive to diet, while genes for lipid uptake in gut become more highly
expressed. Finally, analyses of evolutionary consequences of the salmonid
specific whole-genome duplication on lipid metabolism reveals several
pathways with significantly different (p<0.05) duplicate retention
or duplicate regulatory conservation. We also find a limited number of
cases where the whole genome duplication has resulted in an increased gene
dosage. Our results demonstrate the presence of a life-stage associated
remodeling of lipid metabolism at the gene regulatory level, suggesting an
evolved preparatory optimization of lipid metabolism