ALBERT

Description: Gene expression profile from gill and muscle tissue samples. Juvenile abalones were exposed to a temperature ramp (+3 °C day−1) under hypoxia (50% air saturation) and hypercapnia (~1000 μatm pCO2), both individually and in combination. Experiments are denoted as control (warming under normoxic normocapnia), hypoxia (warming under hypoxic normocapnia), hypercapnia (warming under normoxic hypercapnia, and combined (warming under hypoxic hypercapnia). The table is arranged to be used with the R package MCMC.qPCR (Matz et al., 2013).

Description: Data derived from a study aimed to detect differences in thermal tolerance by investigating the underlying metabolic responses in the green abalone (Haliotis fulgens) under conditions of hypoxia and hypercapnia. Juvenile abalones were exposed to a temperature ramp (+3 °C day−1) under hypoxia (50% air saturation) and hypercapnia (~1000 μatm pCO2), both individually and in combination. Impacts on energy metabolism were assessed by analyzing whole animal respiration rates and metabolic profiles of gills and hepatopancreas via 1H NMR spectroscopy. The experiments are depicted as warming (warming ramp under normoxic normocapnia), hypoxia (warming ramp under hypoxic normocapnia), hypercapnia (warming ramp under normoxic hypercapnia), and combined (warming ramp under hypoxic hypercapnia). Each experiment was accompanied by a Control group, which was exposed to the same water PO2 and PCO2 but at a stable temperature (18 °C).

Description: Transcriptional regulation constitutes a rapid response of marine organisms facing stressful environmental conditions, such as the concomitant exposure to warming, ocean acidification and hypoxia under climate change. In previous studies, we investigated whole-organism physiological patterns and cellular metabolism in gill and muscle of the marine gastropod Haliotis fulgens in response to increasing temperature (18 °C to 32 °C at +3 °C per day) under hypoxia (50% air saturation), hypercapnia (1000 μatm pCO2) and both factors combined. Here, we report investigations of the molecular responses of H. fulgens to temperature and identify mechanisms concomitantly affected by hypoxia and hypercapnia. A de novo transcriptome assembly with subsequent quantitative PCR and correlation network analysis of genes involved in the molecular response were used to unravel the correlations between gene expression patterns under the different experimental conditions. The correlation networks identified a shift from the expression of genes involved in energy metabolism (down-regulated) to the up-regulation of Hsp70 during warming under all experimental conditions in gill and muscle, indicating a strong up-regulation of damage prevention and repair systems at sustained cellular energy production. However, a higher capacity for anaerobic succinate production was evicted in gill, matching with observations from our previous studies indicating succinate accumulation in gill but not in muscle. Additionally, warming under hypoxia and hypercapnia kept mRNA levels of citrate synthase in both tissues unchanged following a similar pattern as muscle enzyme capacity from a previous study, suggesting an emphasis on maintaining rather than down-regulating mitochondrial activity. Keywords: Cellular stress response; Climate change; Gastropod; Gene expression; qPCR