Proteomic and transcriptional analyses of coral larvae newly engaged in symbiosis with dinoflagellates

Many marine cnidarians, such as stony corals, engage in intracellular symbiosis with dinoflagellates, forming the trophic and structural foundation of the coral reef ecosystem. Very little is known about the cellular and molecular mechanisms that are at work in these associations. In this study, we examined changes in both the soluble proteome and the transcriptome of larvae of the Hawaiian solitary coral Fungia scutaria during the onset of symbiosis with Symbiodinium sp. We conducted a comparative host coral proteome analysis using 2-dimensional gel electrophoresis, as well as a comparative host coral transcriptome analysis using a cDNA subtracted library and real-time quantitative PCR. Age-related changes in the larval protein profiles were detected, however virtually no symbiosis-related changes in the protein profiles were evident. Symbiosis-related differences in gene expression were found using a subtracted library, although the differences were very subtle and almost undetectable using real-time quantitative PCR.