EAGER: Biophotonic technologies to design new strategies for coral reef resilience to warmer oceans

Northwestern University, Evanston IL

Investigators

Abstract

Coral reefs are amongst the most diverse ecosystems in the world; more than 500 million people depend on them for coastal protection, marine biodiversity, sustainability of commercial fisheries, and tourism. Over recent decades, climate change-induced ocean warming has resulted in worldwide bleaching and death of corals, with the loss of more than 30% of coral reefs. However, there is wide variability in coral response to heat stress; some corals have developed resilience to thermal stress due to an unknown combination of genetic and gene expression effects. Current conservation efforts are breeding heat-resistant corals to create more resilient stocks, but this could take decades with the slow growth rate of corals. Coral reefs are running out of time. This project proposes an approach to increase the resiliency of coral reefs that will quickly impart physiological changes that improve the corals’ survival to heat stress. This project focuses on developing optical imaging techniques that can understand the role of gene expression in heat stress resiliency. This project also trains undergraduate and predoctoral students to improve the retention of underrepresented groups in STEM careers. Increasingly frequent and intense climate change-derived ocean warming episodes have caused coral bleaching and mortality worldwide, resulting in the collapse of many reef ecosystems. However, because coral species show differential bleaching responses to thermal stress, their potential for acclimatization or adaptation warrants investigation. Coral thermal tolerance involves an unknown combination of genetic effects (adaptation, such as inheritable “heat-resistant genes”) and epigenetic effects (acclimatization, such as changes in overall gene transcription not caused by changes in the underlying DNA). While current restoration efforts are accelerating adaptation by breeding heat-resistant corals, this process can take decades due to the slow growth of corals. Instead, this project proposes development of an epigenetic-based method to increase coral’s transcriptional plasticity and survival in heat stress. Recent advances in mammalian cells have identified the key role chromatin remodeling (changes in the DNA-protein complex structure that regulates gene transcription) plays in gene expression plasticity. This project seeks to test the novel frontier field of regulating transcriptional plasticity in corals by engineering chromatin structure to increase their resilience to heat stress. The project will develop several complementary biophotonics (nanoscale optical imaging and nanosening) technologies for image chromatin remodeling. The project will also develop a model that relates transcriptional plasticity with chromatin conformation and bleaching survival, which can integrate chromatin remodeling imaging with state-of-the-art transcriptomics and chromatin sequencing techniques during a simulated coral heat stress event under controlled conditions. The overarching objective is to use transcriptional reprogramming as a tool to build coral reef resilience to thermal stress as global climate change intensifies. 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.