Molecular basis of cnidarian endosymbiosis and its response to environmental change

• Applicant: Professorin Dr. Annika Guse
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2012 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 221467980

Coral reefs are the world's most diverse marine ecosystems and their existence depends on a functional symbiosis between dinoflagellates (single-celled algae) and their coral host. Elevated seawater temperature causes the obligate symbiosis to break down, a phenomenon known as coral “bleaching”. Most corals (phylum Cnidaria) first initiate symbiosis during larval stages. The impact of environmental stress on coral-larval development is not well understood, mainly because corals are difficult to work with and have slow generation times. I propose to use a novel, experimentally tractable model system, Aiptasia pallida, to analyze how environmental changes affect cnidarian larval development and initiation of symbiosis at the cellular and molecular level. I will establish a thorough cellular description of Aiptasia larval development that will allow me to develop assays to specifically perturb environmental conditions (e.g. temperature, CO2 levels) and then analyze the cellular consequences for progression of larval development and symbiont uptake. Further I will identify conserved genes involved in larval symbiosis and dissect their molecular functions. To directly link laboratory findings using Aiptasia to reef-building corals, I will undertake comparative studies using coral larvae collected in the field. Taken together, these studies will help to understand how environmental changes affect the fidelity of cnidarian development, a process that is crucial for the recruitment of new coral colonies, to compensate for natural and stress-related coral death.

• DFG Programme: Independent Junior Research Groups
• Major Instrumentation: motorized inverted microscope + incubator + objective ; stereo microscope with microinjection setup
• Instrumentation Group: 5000 Labormikroskope ; 5040 Spezielle Mikroskope (außer 500-503)