Stress response of octocoral, Eleutherobia rubra to the increased seawater temperature

Abstract

This study aimed to trace the transcriptional responses in coral exposed to environmental stress and especially to profile the gene expression change of immunity related genes in the azooxanthellate octocoral, Eleutherobia rubra. The coral population and its habitat have been affected by the fast warming current and massive coral death has been observed since 2017. In this study, the coral was exposed to the higher temperature than its habitual temperature and RNAs were extracted to investigate the differentially expressed genes and the transcriptional changes using RNA de novo sequencing. Additionally we investigated the seasonal and regional gene expressions of E. rubra and transcriptional changes of stress responses and immunity related gene groups in thermal stress exposed coral comparing with non-stressed group. We suggest that the investigation of regulatory mechanisms governing stress responses by monitoring the changes of transcriptional profiles can be early warning-molecular markers and it can provide an important source of information on acclimatization or adaptation to external stresses. Also the findings of response to thermal stress and transcriptional regulation can be helpful to understand physiological resilience and acclimatization capabilities of E. rubra in seawater temperature changes and to protect coral biodiversity and ecosystem.