Background • Increasing water temperatures and de-oxygenation of the oceans as a result of global warming may negatively impact the overall health of farmed Atlantic salmon • Few studies have looked at the combined effects of hypoxia and incremental temperature change on gene expression in salmonids • Authors measured gene expression of various stress and immune markers in the liver, which was selected for its role in stress response, nutrient metabolism and immunity
Methods • Total RNA extracted from flash frozen liver tissue of 360 Atlantic salmon subjected to Standard BioTools reverse transcription, preamplification and data collection workflows. • Data collected using the 96.96 GE IFC on Biomark HD • 41 gene target panel included genes related to the following categories: • Heat shock response • Stress response • Oxidative stress response • Cellular metabolism • Immune response • Transcriptional regulation (methylation)
Results • High temperature initiates immune-related transcript expression changes in the liver • Moderate hypoxia at 12 °C impacts hypoxia and stress-related transcript expression, but not immune-related genes • Immune transcript expression at four weeks was less impacted as compared with the initial three-day exposure • Persistent changes observed in epigenetic markers that facilitate thermal acclimation responses Conclusions • Identified several genes that can be used as biomarkers to characterize transcriptional stress response
Results and conclusions
