Published in Abstracts of American Society of Limnology and Oceanography
Annual Meeting 2006
Baseline study of coral-algal symbioses around the Big Island of Hawai`i
Jennifer Hester and Misaki Takabayashi
The symbiotic relationship between scleractinian corals and photosynthetic dinoflagellates endosymbionts, known as zooxanthellae, is critical to the survival of both organisms involved. Zooxanthellae are dinoflagellates of the genus Symbiodinium , and have high sequence diversity. The high level of diversity within this taxon has led to the establishment of clades within the genus, which are further broken down into strains. As of yet, no baseline studies on the genotypes of zooxanthellae present in symbiotic corals have been conducted on the Big Island of Hawaii. In this study, zooxanthella DNA, extracted from Pocillopora meandrina and Porites lobata at two different locations on the island of Hawaii, Puako located on the West side of the island and Leleiwi, located on the East side was examined. It is expected that all samples from this study are from Clade
C, due to the vast majority of zooxanthellae in other areas of the Pacific falling within this clade. Coral samples were collected at both 5 and 15 meters and sampling was repeated in late summer and winter. Zooxanthella DNA was extracted and amplified via
PCR using ITS primers that were designed based on Symbiodinium sequences from
Genbank. Selected samples were amplified using rDNA 18S primers to verify the assumption that all samples were Clade C. Amplified ITS sequence products were cloned, and the resulting sequences were further analyzed. Using pair wise distance analysis and Analysis of Molecular Variance (AMOVA), the presence of any potential relationships between zooxanthellae type and parameters such as coral host species, depth, location, and season was investigated. Data from this baseline study will provide valuable information as to the dynamics of zooxanthella ecology and host-symbiont relationships in Hawaiian corals and can be used in subsequent studies of ecological shifts due to climate change.
zooxanthellae, Symbiodinium , ITS, Pocillopora meandrina , Porites lobata , Clade C