Cellular and Molecular Mechanisms Governing Cnidarian/Dinoflagellate Mutualisms: Cell Biology, Innate Immunity, Functional Genomics

Oregon State University, Corvallis OR

Investigators

Abstract

Cellular and Molecular Mechanisms Governing Cnidarian/Dinoflagellate Mutualisms: Cell Biology, Innate Immunity, Functional Genomics Virginia M. Weis, Oregon State University A grant has been awarded to Dr. Virginia Weis of Oregon State University to examine the cellular and molecular interactions between cnidarians, such as reef-building corals, and their single-celled symbiotic dinoflagellate algae resident within their tissues. Weis' group will identify and characterize genes and cellular pathways in host corals and closely related anemones that function in the establishment and maintenance of these important mutualistic interactions. These is increasing evidence that the cellular pathways that function in the invasion by microbial parasites and pathogens of animals hosts are the same ones used in the establishment of beneficial symbioses such as corals. This award will: 1) examine inter-partner molecular signaling during the onset of symbiosis in microscopic larval corals that acquire their symbionts from their surroundings, 2) use state-of-the-art genomics techniques to search the world's databases for cnidarian genes important in fighting off invaders and then determine if these same genes are at play during this beneficial symbiosis, 3) examine the function of a cellular signaling pathway, that is known to function in cell growth in other systems, in the control of the symbiosis. Symbiotic associations between two or more unrelated organisms are found throughout every ecosystem. These relationships encompass a spectrum of lifestyles, from mutualistic to parasitic, and from extracellular to intracellular. Among the most significant marine mutualisms are those between corals and their algal symbionts, which together form both the trophic and structural foundation of the entire coral reef ecosystem. A great deal is known about corals on a macroscale level, such as their global distribution and ecology. However, microscale processes of inter-partner communication and regulation that occur during the initiation, establishment and maintenance of these symbioses remain largely unexplored. A lack of basic knowledge of these processes has hampered efforts to understand the global phenomenon of coral bleaching, which is the result of the breakdown of the symbiosis. Widespread bleaching, which leads to coral death and reef degradation, is considered a serious environmental threat. This study will take a multileveled approach to the examination of the events surrounding the initiation, establishment and maintenance of symbioses between corals and their symbiotic algae.