THE EFFECT OF ACUTE THERMAL STRESS ON GENE EXPRESSION LEVELS OF HSP70 IN THE ANTARCTIC NOTOTHENIOID, Notothenia coriiceps

The waters of the West Antarctic Peninsula are known as one of the most cold, stable environments on earth and organisms living within, such as the fish Notothenia coriiceps, have become highly specialized over evolutionary time. However, water temperatures in this environment have been steadily warming over the past two decades due to global climate change. In addition to the challenges created by increasing temperatures N. coriiceps will also be faced with difficulty meeting oxygen demands to carry out metabolic processes due to the decrease solubility of oxygen in warmer environments. Heat stress proteins (Hsps) are critical molecules that assist in intracellular processes. Hsp genes are highly conservative and upregulated in all species. However, it has been shown that many Antarctic organisms are unable to mount a heat shock response (HSR) making them highly vulnerable to the effects of global warming. Previous studies have shown that Hsps are strongly upregulated in the red blood cells (RBCs) of most fish in response to thermal stress, but date the HSR has not been investigated in the red blood cells from Notothenioid fishes. As a point of departure, our study investigated the HSR N. coriiceps red blood cells. Blood was collect from fish exposed to either an elevated, but sub-lethal temperature (4°C; n=8) or ambient conditions (0.5°C). Our results show that transcript for HSP70 is expressed at detachable levels in N. coriiceps erythrocytes. Additional studies analyzing changes in relative mRNA expression as a result of thermal stress are in progress