Assessing Gene Expression Changes in the Octocoral Briareum asbestinum Due to Vibrio coralliilyticus Exposure

Author

• Hailey Poignant, Nova Southeastern UniversityFollow

Defense Date

8-4-2026

Document Type

Thesis

Degree Type

Master of Science

Degree Name

Biological Sciences

First Advisor

Jose Lopez

Second Advisor

Matias Gomez Corrales

Third Advisor

Navi Gill

Keywords

Briareum asbestinum, Vibrio coralliilyticus, coral disease, transcriptomics, differential gene expression, innate immune response, climate change

Abstract

Coral reefs are an essential ecosystem home to tons of marine diversity that humans have also  learned to rely on, but they are harmed by climate change and the increasing prevalence of disease. While most studies focus on reef-building coral, octocorals also warrant attention to reveal how they respond to similar stressors. Octocorals share distant ancestry with reef-building corals, so there may be overlap in their immune responses which could provide insight into future restoration projects. To understand how octocorals respond to disease, the octocoral Briareum asbestinum was used as a model to examine gene expression changes caused by the presence of the opportunistic pathogen Vibrio coralliilyticus. This was done by collecting ten unique coral samples and subjecting them to V. coralliilyticus inoculation. Following the inoculation, a recovery period was allowed. This provided data revealing the transcriptome pre�pathogen, during pathogen, and post-pathogen exposure. From this experiment we were able to ask if the introduction of V. coralliilyticus to B. asbestinum would cause transcriptomic alterations and if those differentially expressed genes were involved in the coral immune response. Through differential gene expression analyses, multiple genes associated with the immune response were identified. During each time point the coral had unique responses to the pathogen. Most immune-related genes were enriched post-recovery which suggests that the coral host experiences a delayed response to this pathogen. These genes were consistently associated with amoebocyte activity and toll-like receptors and signaling pathways which contributed to the innate immune responses. Overall, the results support the hypotheses that the V. coralliilyticus’ presence induces an immune response in B. asbestinum, especially in the post-recovery period.

NSUWorks Citation

Hailey Poignant. 2026. Assessing Gene Expression Changes in the Octocoral Briareum asbestinum Due to Vibrio coralliilyticus Exposure. Master's thesis. Nova Southeastern University. Retrieved from NSUWorks, . (248)
https://nsuworks.nova.edu/hcas_etd_all/248.