Effects of cold stress and heat stress on coral fluorescence in reef-building corals

Abstract

Widespread temperature stress has caused catastrophic coral bleaching events that have been devastating for coral reefs. Here, we evaluate whether coral fluorescence could be utilized as a noninvasive assessment for coral health. We conducted cold and heat stress treatments on the branching coral Acropora yongei, and found that green fluorescent protein (GFP) concentration and fluorescence decreased with declining coral health, prior to initiation of bleaching. Ultimately, cold-treated corals acclimated and GFP concentration and fluorescence recovered. In contrast, heat-treated corals eventually bleached but showed strong fluorescence despite reduced GFP concentration, likely resulting from the large reduction in shading from decreased dinoflagellate density. Consequently, GFP concentration and fluorescence showed distinct correlations in non-bleached and bleached corals. Green fluorescence was positively correlated with dinoflagellate photobiology, but its closest correlation was with coral growth suggesting that green fluorescence could be used as a physiological proxy for health in some corals.

Hsp60 expression profiles in the reef-building coral Seriatopora caliendrum subjected to heat and cold shock regimes

“…As widely reported, seawater temperature changes have been recognized as the most important environmental variable affecting coral physiology, with bleaching as a late cellular event (Ainsworth et al, 2008). To date, a lot of effort has been focused on understanding the effects of heat stress on the physiology of corals (Lesser, 2004;Ferrier-Pag es et al, 2007;Weis, 2008;Fitt et al, 2009;Vidal-Dupiol et al, 2009;Mayfield et al, 2012Mayfield et al, , 2013Rodolfo-Metalpa et al, 2014), while the cellular responses of corals subjected to cold stress have received less attention (Roth et al, 2012;Roth and Deheyn, 2013;Rodríguez-Troncoso et al, 2014). For this reason, in the present study the modulation of the Hsp60 over time was analyzed in a thermal susceptible scleractinian coral, S. caliendrum, subjected to different regimes of heat and cold shocks.…”

The engine of the reef: photobiology of the coral–algal symbiosis

“…During temperature stress, there is a rapid decline in GFP prior to coral bleaching providing an early signal of declining coral condition (Roth and Deheyn, 2013). While the function of FPs is uncertain, it is clear they are involved in the photophysiological response of the coral–algal symbiosis.…”

Heat Stress and Gut Health in Broilers: Role of Tight Junction Proteins

“…1 As this upward trend continues, it will serve as a severe environmental stress factor on all forms of the life. 2,3 One of the most affected industries will be the livestock industry. Poultry, in particular, appears to be very heat sensitive animals, due to lack of sweat glands and high metabolic activity.…”