Elucidating mechanisms of symbiont recovery and resilience in cnidarian-algal symbiosis using a green mutant symbiont

Coral reefs are among the most vibrant and productive ecosystems on the planet, supporting a multitude of marine species and benefiting millions of people through food, tourism, and coastal protection. However, when ocean temperatures rise, corals can lose their microscopic algal partners—essential organisms that provide energy through photosynthesis—resulting in a condition known as coral bleaching. This project aims to better understand how corals recover these algal partners after such stress. Using a novel algal strain and advanced live imaging techniques, this project will study how these algae proliferate and re-establish their relationship with the coral host. Beyond advancing scientific understanding, this research will inform the design of practical solutions for coral recovery and ecosystem restoration. These innovations are being developed alongside entrepreneurship training to promote real-world impact. The project also emphasizes education and mentorship by involving students at multiple levels in hands-on research and professional development. Through discovery and training, this work aims to advance reef conservation. This project aims to elucidate the underlying mechanisms that enable symbiotic dinoflagellates to proliferate within cnidarian hosts after thermal stress disrupts the symbiosis. Leveraging a Symbiodiniaceae pigment mutant and the small sea anemone Exaiptasia diaphana model system, the study employs high-resolution live imaging to track symbiont dynamics in vivo. The project comprises three integrated aims: (1) defining the cellular mechanisms of symbiont proliferation under elevated temperatures, (2) applying computational models to simulate symbiont population dynamics and predict recovery trajectories, and (3) using single-cell RNA-seq to identify molecular interactions between host cells and symbionts. The research also includes an applied component aimed at informing the development of tools to promote symbiont expansion in compromised corals, with commercialization pathways explored through NSF I-Corps training. This integrative framework will provide new insights into the regulation of coral-algal symbiosis and contribute to efforts to support reef sustainability. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.