Physiological resilience of a temperate soft coral to ocean warming and acidification

Abstract

Atmospheric concentration of carbon dioxide (CO) is increasing at an unprecedented rate and subsequently leading to ocean acidification. Concomitantly, ocean warming is intensifying, leading to serious and predictable biological impairments over marine biota. Reef-building corals have proven to be very vulnerable to climate change, but little is known about the resilience of non-reef-building species. In this study, we investigated the effects of ocean warming and acidification on the antioxidant enzyme activity (CAT-catalase, and GST-glutathione S-transferase), lipid peroxidation (using malondialdehyde, MDA-levels as a biomarker) and heat shock response (HSP70/HSC70 content) of the octocoral Veretillum cynomorium. After 60 days of acclimation, no mortalities were registered in all treatments. Moreover, CAT and GST activities, as well as MDA levels, did not change significantly under warming and/or acidification. Heat shock response was significantly enhanced under warming, but high CO did not have a significant effect. Contrasting to many of their tropical coral-reef relatives, our findings suggest that temperate shallow-living octocorals may be able to physiologically withstand future conditions of increased temperature and acidification.

Thermal preconditioning in a reef-building coral alleviates oxidative damage through a BI-1 mediated antioxidant response

“…Conversely, the role of host-derived antioxidants in bleaching and thermal resilience remains disputed. While pioneering studies show antioxidant activation in adult coral host tissue and larvae under heat stress (16,(25)(26)(27)(28)(29), more recent experiments have failed to find this pattern (10,22). However, the coral host control of the level of oxygen radicals and ROS is likely a major component in the dynamics of coral-algal symbiosis maintenance (18,30).…”

Gonadal Antioxidant Responses to Seawater Acidification and Hypoxia in the Marine Mussel Mytilus Coruscus

“…Lopes et al (2018) found GST activities in the soft coral Veretillum cynomorium did not change signi cantly under warming and acidi cation. The GST activity in our experiment signi cantly decreased under pH 7.3, indicating that extreme low pH disrupted the balance of GST.…”

Gene Expression of Endangered Coral (Orbicella spp.) in Flower Garden Banks National Marine Sanctuary After Hurricane Harvey

“…A recent experimental study in Acropora millepora, a reef-building coral in the Great Barrier Reef, also found a strong antioxidant response to reduced salinity (Aguilar et al, 2019), suggesting that this response mechanism is conserved across coral genera. The upregulation of antioxidantencoding genes has been described in corals exposed to a variety of biotic and abiotic threats, including increased temperature (Barshis et al, 2013;Dixon et al, 2015), acidification (Davies et al, 2016;Lopes et al, 2018), and disease (Wright et al, 2015(Wright et al, , 2017Daniels et al, 2015).…”