I will talk about what we have learned from studying symbioses in algae and corals. Origin of the photosynthetic organelle in algae led to the major rewiring of host metabolic pathways to accommodate the novel energetic organelle. Our work on the photosynthetic amoeba Paulinella provides key insights into these processes and provides an explanation for why primary endosymbiosis are so fleetingly rare. I will then discuss genome evolution in Scleractinia that address how symbioses impact genome size and gene content in the dinoflagellates symbionts and how population size impacts coral nuclear genomes. This work lays the foundation for ongoing multi-omics research that addresses stress responses in the coral holobiont and in the animal. I will stress the use of metabolomic data that provides diagnostic stress markers in corals.
Debashish Bhattacharya is a Distinguished Professor in the Department of Biochemistry and Microbiology at Rutgers University, New Brunswick, USA. His group and collaborators work in the field of algal genomics and evolution and investigate the complex paths of algal origin through endosymbiosis (http://dblab.rutgers.edu). Phylogenetics, genomics, a variety of bioinformatic approaches, and functional methods are used to understand how organelles were integrated into “host” cell metabolism. His group works on the intriguing photosynthetic amoeba Paulinella that gained its photosynthetic organelle (plastid) independent from plants and algae and provides an invaluable resource for understanding how organelles evolve. The Bhattacharya group also pursues research on coral biology, evolution, and conservation using multi-omics and genetic approaches (https://sites.rutgers.edu/coralbase). His group is developing metabolomics methods for diagnosing coral health using a portable instrument. Debashish is visiting UQ as a Partner Investigator of a funded ARC Discovery Project (CI: Dr Cheong Xin Chan) to investigate genome evolution of coral symbionts (Symbiodiniaceae) from the Great Barrier Reef.