"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
The global emergence of infectious diseases has radically altered marine ecosystems, especially tropical reef communities. Reef-building corals, the cornerstones of tropical reefs, have been especially hard hit. A prime example is White Band Disease (WBD) on the Caribbean Acropora corals, the staghorn coral A. cervicornis and elkhorn coral A. palmata, which caused an unprecedented die-off of these dominant shallow-water corals, and spurred their threatened listings on the USA Endangered Species Act (ESA). While significant inroads have been made towards understanding the basic etiology and ecology, for many coral diseases including WBD, little to nothing is known about the genetic response of the coral host during disease exposure and the genetic basis of natural disease resistance in corals, even though this knowledge is fundamental to understanding coral host-pathogen interactions and critical to the conservation of these threatened corals.
Using the Caribbean staghorn coral A. cervicornis and WBD as the host-pathogen system, this study will produce the first experimental data on the genetics of disease infection, innate immunity and host resistance in reef-building corals. In situ transmission experiments will identify resistant and susceptible staghorn corals. A transcriptome-wide survey of resistant and susceptible corals exposed to WBD will identify genes that are differentially expressed (i.e. up or down regulated) when corals are exposed to disease, and identify gene expression patterns that differ between resistant and susceptible staghorn corals. A survey of the staghorn coral genome will then be used to identify genetic markers associated with WBD resistance, and survey the frequencies of these resistance markers in remnant staghorn coral populations from across the Caribbean. These transcriptome and genome surveys will provide a comprehensive picture of coral gene regulation during disease exposure and the genetic mechanisms underlying natural disease resistance.
The broader impacts include outreach efforts through journal publication and media outlets to capture the public's awareness on topic of the natural disease resistance in an ESA listed coral. Field and laboratory training and experiences are planned for multiple graduate and undergraduate students. Curricula will be developed to teach students about genes, DNA and coral reef health in both English and Spanish, and the materials will be distributed to teachers in the US and Panama. The transcriptome sequence data and microarray platform will be freely available to the scientific community as an open resource. In addition, this research will advance knowledge of the genes involved in coral disease exposure, innate immunity and host-resistance, while providing conservation managers in the Caribbean the first information on natural disease resistance in a threatened coral and a genetic tool for surveying the future resilience of staghorn corals populations to WBD.
