Cell type-specific immune regulation under symbiosis in a facultatively symbiotic coral.

Many cnidarians host single-celled algae within gastrodermal cells, yielding a mutually beneficial exchange of nutrients between host and symbiont, and dysbiosis can lead to host mortality. Previous research has uncovered symbiosis tradeoffs, including suppression of immune pathways in hosts, and correlations between symbiotic state and pathogen susceptibility. Here, we used a multiomic approach to characterize symbiotic states of the facultatively symbiotic coral Oculina arbuscula by generating genotype-controlled fragments of symbiotic and aposymbiotic tissue.

Microbial Depletion Is Associated with Slower Cnidarian Regeneration.

Microbiomes play an important role in physiology and development in cnidarians, but how these communities influence tissue regeneration is poorly understood. Here, we examined the effects of antibiotic exposure on regeneration and microbial communities in two cnidarian models, the sea anemones Nematostella vectensis (non-symbiotic, hereafter, Nematostella) and Exaiptasia diaphana (symbiotic, hereafter, Aiptasia). Bisected animals were incubated in either sterile or antibiotic-treated artificial seawater for 7 days and regeneration was monitored daily.

Interspecies differences in the transcriptome response of corals to acute heat stress.

Rising sea surface temperatures threaten the survival of corals worldwide, with coral bleaching events becoming more commonplace. However, different coral species are known to exhibit variable levels of susceptibility to thermal stress. To elucidate genetic mechanisms that may underlie these differences, we compared the gene repertoire of four coral species, , , and , that were previously demonstrated to have differing responses to acute thermal stress.

Warm temperature alters the chemical cue preference of Acropora tenuis and Heliopora coerulea larvae.

Larvae released into the water column rely on chemical cues from the benthos for successful settlement. However, larval preference for substrates may be affected by rising seawater temperature brought about by global climate change. In this study, we examined the effect of elevated temperature on chemical cue preference by larvae of the scleractinian coral, Acropora tenuis, and the octocoral, Heliopora coerulea, collected from northwestern Philippines.