Publication Date:
2024-03-15
Description:
Ocean acidification (OA) has both detrimental as well as beneficial effects on marine life; it negatively affects calcifiers while enhancing the productivity of photosynthetic organisms. To date, many studies have focused on the impacts of OA on calcification in reef-building corals, a process particularly susceptible to acidification. However, little is known about the effects of OA on their photosynthetic algal partners, with some studies suggesting potential benefits for symbiont productivity. Here, we investigated the transcriptomic response of the endosymbiont Symbiodinium microadriaticum (CCMP2467) in the Red Sea coral Stylophora pistillata subjected to different long-term (2 years) OA treatments (pH 8.0, 7.8, 7.4, 7.2). Transcriptomic analyses revealed that symbionts from corals under lower pH treatments responded to acidification by increasing the expression of genes related to photosynthesis and carbon-concentrating mechanisms. These processes were mostly up-regulated and associated metabolic pathways were significantly enriched, suggesting an overall positive effect of OA on the expression of photosynthesis-related genes. To test this conclusion on a physiological level, we analyzed the symbiont's photochemical performance across treatments. However, in contrast to the beneficial effects suggested by the observed gene expression changes, we found significant impairment of photosynthesis with increasing pCO2. Collectively, our data suggest that over-expression of photosynthesis-related genes is not a beneficial effect of OA but rather an acclimation response of the holobiont to different water chemistries. Our study highlights the complex effects of ocean acidification on these symbiotic organisms and the role of the host in determining symbiont productivity and performance.
Keywords:
Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Bicarbonate ion; Bicarbonate ion, standard deviation; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Chromista; Direction; Duration; Fold change; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gene expression (incl. proteomics); Gene name; Laboratory experiment; Laboratory strains; Myzozoa; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; pH, standard deviation; Photosynthetic efficiency; Photosynthetic efficiency, standard error; Phytoplankton; Primary production/Photosynthesis; Registration number of species; Salinity; Sample ID; Single species; Species; Symbiodinium microadriaticum; Temperature, water; Treatment; Type; Uniform resource locator/link to reference
Type:
Dataset
Format:
text/tab-separated-values, 21554 data points
Permalink
