Our group investigates the cellular and molecular interactions underlying mutualistic symbioses between cnidarians, such as corals and anemones, and their photosynthetic dinoflagellate symbionts Symbiodinium spp. These partnerships are of fundamental importance as they form the trophic and structural foundation of coral reef ecosystems. We are interested in the establishment, maintenance and breakdown of these cooperative associations and approach the study of these phenomena at the cellular and molecular level. The Weis group has used a variety of model associations in these examinations and has in recent years focused on the Hawaiian stony coral, Fungia scutaria; a tropical sea anemone, Aiptasia pallida; and a temperate sea anemone, Anthopleura elegantissima.