“PhagoPhoRe”: New working group investigates the coexistence of host animals and algae – the European Research Council provides funding of 1,489,000 euros
Symbioses are important for the diversity of life. The coexistence of two organisms for mutual benefit shapes ecosystems and supports biodiversity. For example, corals and algae live together: The algae provide corals with oxygen and nutrients from their photosynthesis, while the corals provide them with protection and ideal living conditions in return. Since December 1, Dr. Nils Rädecker has been investigating how this symbiosis comes about and what determines whether it is successful or fails in a new junior research group at the Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB). He also received a Starting Grant from the European Research Council (ERC) for his research.
A special type of symbiosis is photosymbiosis, between so-called heterotrophic and photosynthetic organisms, i.e. those that carry out photosynthesis. While photosynthetic organisms can satisfy their energy requirements by using sunlight, heterotrophic organisms have to feed themselves with the help of other organisms. This type of coexistence has contributed to the evolution of plants and plays a major role in global nutrient cycles. In the oceans, algae in particular enter into such symbioses with heterotrophic organisms, for example with corals. Nils Rädecker and his new research group “Photosymbioses” at the HIFMB are investigating why and how these relationships have developed and which factors influence them today. In the “PhagoPhoRe” project, the group will focus on the symbioses in which algae live in the cells of the host animal. Nils Rädecker received a Starting Grant of 1,489,000 euros from the European Research Council for the project.
“With the help of modern technologies in microscopy and molecular science, we want to find out in ‘PhagoPhoRe’ whether unicellular algae can influence the immune system of their hosts,” says Rädecker, describing his project. Algae survive inside the host because they excrete the nutrients obtained through photosynthesis and thus imitate an active digestive process. “This link between photosynthesis and the maintenance of symbiosis could help us to understand why photosymbioses have repeatedly developed in evolution and why they are now threatened by climate change,” Rädecker continues. One example of a disturbed symbiosis is coral bleaching, in which the corals reject the algae living with them, thereby losing their nutrient suppliers and ultimately dying.