The abundance of reef-building corals has declined dramatically over the last decades. The main causes of coral loss are related to ocean warming, nutrient pollution and disease outbreaks, all resulting from anthropogenic-induced climate change. Observations indicate that number and prevalence of coral diseases have increased over the last two decades and new epizootics nearly every year suggest that environmental stressors drive or exacerbate coral disease. This project will examine coral resistance to pathogens and variation in innate immunity, as well as quantify the effects of ocean warming and nutrient pollution on the effectiveness of coral immune responses. The project will focus on the Montastraea faveolata Yellow Band Disease (YBD) system. The genus Montastraea is one of the most important groups of corals of modern western Atlantic coral reefs, however, Montastraea spp. populations have declined dramatically mainly due to bleaching and disease.
Using assays for cellular and cell-free processes in coral immunity, the PIs will examine the variability in disease resistance in naturally infected corals, the reaction time and recovery time from temperature stress and how the combination of stressors influence coral immunity in the presence of YBD pathogens. This project will also train undergraduates and graduate students at multiple universities, and promote exchange between four universities. Funding will support a novel service-learning project. Undergraduate students from an upper-level marine biology course will prepare and execute a lesson plan for junior high school students based on concepts from their course and this project. One of the investigators on this project will collaborate with professional educators and outreach specialists at a Planetarium and a public-oriented Science Center to develop an interactive museum display and K-4 summer camp programs.
The incredible diversity of coral reef ecosystems is being threatened by factors associated with global climate change and local pollution. Across the globe, coral diseases are increasing and killing more corals. Reefs in the Caribbean have been particularly hard hit: disease outbreaks in the area have left their mark with an overall loss of diversity in both corals and the vibrant communities they support. Seeing this increase in frequency and severity of diseases affecting coral reefs on a global scale has made deciphering the coral immune systems a priority. Intellectual merit This project allowed us to make significant headway in what we know about coral immunity and how it is affected by temperature stress. When our project was first funded, significant bleaching was observed in Puerto Rico and the eastern Caribbean. We seized this opportunity to learn how natural temperature stress that causes this catastrophic loss of the algal symbiont affects immunity. We conducted a variety of analyses that allowed us to integrate the protein, cellular and genomic responses. We found that many pathways including many immune and cell signaling pathways were downregulated by bleaching, possibly leaving the coral susceptible to disease. More importantly we followed these individual corals over time and found that even when they recover their algal symbionts, many genes are still affected. Interestingly the corals try to increase DNA and protein synthesis to make up for lost time. Another significant study looked at how the immune system of Caribbean coral us shaped by their past experiences. This study found that older lineages of corals had a more robust immune system than newer evolved lineages. The disease susceptibility of these species was also correlated to lineage age, and older lineages were susceptible to fewer diseases. This study is a culmination of several smaller studies published due to this award that found differences between the immune capabilities of coral species when they were exposed to temperature stress and pathogens. We also found that disease susceptibility and growth rates could also lead to inherent differences in immunity. Broader impacts The broader impact of all these studies is a starting point for projecting which coral species may fare better with continuously changing biotic and abiotic conditions. This information will be integrated into trait models that are seeking to define the trajectories of different coral species. Looking within the coral, this work also identified specific pathways that are involved in immunity and linked genes to proteins for a nice correlation between genomics and phenotype. Activities and results from this project have already impacted the community at UTA and in the Dallas-Fort Worth area. Our participation in Earth Day Texas over 3 years have engaged over 2000 students, parents and other visitors in coral reef issues. At the Hispanic Engineering, Science and Technology (HESTEC) Week, over 500 junior high students attended a coral reef workshop ran by Dr. Mydlarz. Through course specific outreach projects, 900 Junior High students learned about issues facing marine ecosystems and coral reefs. Many of these students have received mementos from the experience that acknowledges UTA and NSF. On campus, this project has trained a total of 4 (3 female graduate students), over 15 undergraduate students (many from groups underrepresented in science) and 1 Latino post-doc. 3 of the graduate students have graduated and 1 has a faculty job. Many of the undergraduate students trained as part of the project are currently in graduate school or professional school, or working as teachers or in science. Mydlarz has been the subject of 4 articles on her work in University publications that helps spread the word of coral reef to the greater university and alumni community. Social media attention for papers published in 2014 allowed interested citizens and readers of outlets like THE CONVERSATION and CLIMATE WIRE to learn about these NSF funded projects.
