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Coral disease has progressively become one of the most pressing issues affecting coral reef survival. In the last 50 years, several reefs throughout the Caribbean have been severely impacted by increased frequency and intensity of disease outbreaks leading to coral death. A recent example of this is stony coral tissue loss disease which has quickly spread throughout the Caribbean, devastating coral reef ecosystems. Emerging from these disease outbreaks has been a coordinated research response that often integrates ‘omics techniques to better understand the coral immune system. ‘Omics techniques encompass a wide range of technologies used to identify large scale gene, DNA, metabolite, and protein expression. In this review, we discuss what is known about coral immunity and coral disease from an ‘omics perspective. We reflect on the development of biomarkers and discuss ways in which coral disease experiments to test immunity can be improved. Lastly, we consider how existing data can be better leveraged to combat future coral disease outbreaks.
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Proteomic Investigation of a Diseased Gorgonian Coral Indicates Disruption of Essential Cell Function and Investment in Inflammatory and Other Immune Processes
Abstract As scleractinian coral cover declines in the face of increased frequency in disease outbreaks, future reefs may become dominated by octocorals. Understanding octocoral disease responses and consequences is therefore necessary if we are to gain insight into the future of ecosystem services provided by coral reefs. In Florida, populations of the octocoral Eunicea calyculata infected with Eunicea black disease (EBD) were observed in the field in the fall of 2011. This disease was recognized by a stark, black pigmentation caused by heavy melanization. Histological preparations of E. calyculata infected with EBD demonstrated granular amoebocyte (GA) mobilization, melanin granules in much of the GA population, and the presence of fungal hyphae penetrating coral tissue. Previous transcriptomic analysis also identified immune trade-offs evidenced by increased immune investment at the expense of growth. Our investigation utilized proteogenomic techniques to reveal decreased investment in general cell signaling while increasing energy production for immune responses. Inflammation was also prominent in diseased E. calyculata and sheds light on factors driving the extreme phenotype observed with EBD. With disease outbreaks continuing to increase in frequency, our results highlight new targets within the cnidarian immune system and provide a framework for understanding transcriptomics in the context of an organismal disease phenotype and its protein expression.
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- PAR ID:
- 10121504
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Integrative and Comparative Biology
- Volume:
- 59
- Issue:
- 4
- ISSN:
- 1540-7063
- Page Range / eLocation ID:
- p. 830-844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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