Synergistic effects of ocean acidification and warming on coral host, Symbiodinium and nutrients exchange-based symbioses indicated by metatranscriptome

Abstract

Global climate changes e.g. ocean acidification and warming caused by anthropogenic emission of CO2 are the greatest global threat to coral reef ecosystems. However, compared with the knowledge of Symbiodinium, little is known about the synergistic effects of combined ocean acidification and warming on the coral host and coral-Symbiodinium symbioses. In this study, metatranscriptomic analysis was performed to reveal the response of coral host and its symbiotic Symbiodinium to acidification (A), warming (H) and combined acidification and acidification (AH), using branching A. valida and massive G. fascicularis as models in a laboratory simulation system. RNA-Seq-based differently expressed genes (DEGs), together with coral’s morphological change, suggested the synergistic effects of AH on the coral host and coral-Symbiodinium symbioses, e.g. photosynthesis inhibition and negative effect on nutrients exchange between the host and its Symbiodinium. Particularly, AH showed a far greater impact on coral host than on Symbiodinium. These findings provide novel insights into the molecular mechanism of coral holobionts’ response to future extreme ocean acidification and warming, meanwhile highlight the molecular evidence for the different tolerance of branching and massive corals to environmental changes.

Synergistic and antagonistic interactions of oxybenzone and ocean acidification: new insight into vulnerable cellular processes in non-calcifying anthozoans

“…A first step biomarker development is to identify GOIs responsive to laboratory-controlled conditions on a single stressor (i.e., exposure to OA or BP-3). Eight GOIs representing collagen synthesis, zinc transport, transient receptor cation channel, and proteins containing a fibrinogen domain have previously demonstrated cnidarian responsiveness to OA ( Moya et al, 2012 ; Wu et al, 2022 ). Three GOIs (C3, 17βHSD14, 17βHSD12) previously demonstrated responsiveness to BP-3 ( Morgan et al, 2022 ).…”