Objective: Increasing atmospheric CO2 concentration are causing changes to the seawater carbonate chemistry, lowering the pH and we study potential impacts of these changes at the molecular level in a non-calcifying, marine polychaete species Platynereis dumerilii.
Methods: We investigate the relative expression of carbonic anhydrase (CA), Na+/H+ exchangers (NHE), and calmodulin (CaM) genes from P. dumerilii under acidified seawater conditions (pH 7.8) induced by CO2 using qPCR.
Results: mRNA expression of CA in the CO2-induced worms was significantly up-regulated at low pH conditions (pH 7.8, 1h), suggesting changes in acid-base balance. In contrast, the expression of NHE and CaM showed no significant change. In addition, we compare these results to a previous study using inorganic acid (HCl)-induced pH changes.
Conclusions: Results suggest that carbonate chemistry has an impact on gene expression that differs from pH-associated change. To our knowledge, this is the first study that compares low pH exposure experiments using HCl and CO2 as the inducing agents.
Wäge J., Rohr S., Hardege J. D. & Rotchell J. M., 2016. Short-term effects of CO2-induced low pH exposure on target gene expression in Platynereis dumerilii. Journal of Marine Biology & Oceanography 5:2. Article.