Meeting Abstract

47.4  Saturday, Jan. 5  Using functional genomics to characterize the physiological response of polar fishes to a multi-stressor scenario PLACE, S.P.; Univ. South Carolina

Antarctic fishes of the suborder Notothenioidei have displayed incredibly narrow physiological limits in previous single stressor studies and may be particularly vulnerable to the impacts of global climate change. Given the propensity for both adaptive and potentially mal-adaptive traits found among many notothenioid species, this system provides a unique opportunity to examine physiological trade-offs associated with acclimation to a multi-stressor environment. Using both field and laboratory-based analyses, we have combined approaches from the fields of functional genomics and organismal physiology to examine how global climate change may impact species performance. Our previous data has shown the emerald notothen, Trematomus bernacchii, displays a rapid acclimatory response with respect to resting metabolic rates following exposure to elevated temperature or pCO2, and that these two stressors can act synergistically to further impact their physiological response. Here, we highlight the molecular mechanisms underlying the physiological response of T. bernacchii after long-term acclimation to elevated pCO2 and temperature. RNAseq analysis of mRNA levels in gill, liver and brain tissue from fish acclimated up to 28 days under the multi-stressor treatment revealed a tissue specific response in this notothenoid species. Prominent cellular pathways identified in the analyses include metabolic adjustments involving mobilization of lipid stores and a moderate up-regulation of genes involved in the classical cellular stress response. These transcriptome profiles give us insight into the physiological impacts of sub-lethal stress and may provide an indication of the costs associated with adapting to global climate change.