Gene expression by the cold-water octocoral Dentomuricea aff. meteor during an ex-situ experiment testing the effects of mining-generated sediment plumes

We report the results of an aquaria-based experiment testing the effects of suspended particles generated during potential mining activities, on a common habitat-building coral species in the Azores, Dentomuricea aff. meteor. Coral fragments were maintained in 10-L aquaria and exposed to three experimental treatments for a period of four weeks at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores): (1) control conditions (no added sediments); (2) suspended polymetallic sulphide (PMS) particles; (3) suspended quartz particles. Gene expression profiles in D. aff. meteor were used to evaluate the physiological pathways involved in the response to exposure to PMS and quartz particles. Coral fragments were collected from each treatment at times 0, 3, and 13 days and for the control and quartz treatments also at time 27 days. The study targeted genes involved in cellular stress and antioxidant reaction system (heat shock protein, superoxide dismutase, ferritin), cell structure/integrity (α-carbonic anhydrase, receptor-type protein tyrosine phosphatase) and immune responses (toll-like receptor, lysozyme, rel homology domain, ferritin).