Transcriptomic Landscape of the Coral Holobiont in White Plague Disease
Pyrosequencing studies on scleractinian corals have primarily focused on surveying healthy specimens or those exposed to laboratory treatments of various abiotic stressors (i.e. temp, pH, DOC, and other nutrients). Few studies have applied these next generation techniques in corals, as it pertains to disease.
Biological agents that affect multiple coral species are of particular interest to understand compositional and functional changes in the coral holobiont. White Plague Disease (WPD) is described as a bacterial disease, reported to infect over forty coral species, and responsible for epidemics that have caused significant reef decline in the Caribbean. Although a pathogen was confirmed by Koch's postulates for WPD, recent 16S barcoding efforts failed to detect and verify this pathogen in diseased samples of the same and other species. However, drastic shifts in the microbial community were observed.
So far, a holistic understanding of coral disease as it affects the coral holobiont is missing. Here, we apply comparative metatranscriptomics to the "dirty" holobiont (i.e. the coral, algal, and bacterial community) to better understand WPD infection. We collected tissue samples from healthy and WPD-compromised Montastraea sp. samples that were collected at reef sites off Puerto Rico (USA) to generate expression profiles. Metagenomic analysis of the entire microbial community will also be conducted to validate the bacterial transcriptome findings in each sample type. This will be the first study to apply dual metagenomics and -transcriptomics pyrosequencing to obtain a global assessment of a coral disease in situ.