Subject and Goal

This project is devoted to the study of the circadian clock of the unicellular green alga Chlamydomonas reinhardtii by a systems biological approach combining modern experimental techniques with modelling and computer simulations. In particular, the project is aimed at producing genetically modified strains of C. reinhardtii that show an improved nitrogen use and photosynthetic capacity specifically during day-phase. We aim to establish an in silico model that allows one to better understand the circadian clock of C. reinhardtii. Based on simulations with that model, regulatory genes that are involved in nitrogen metabolism and photosynthesis will be selected for genetic manipulation. Thereby, the translation of their mRNAs will be put under the control of the circadian clock. This combined experimental and modelling approach will lead to a systems-theoretical view on this part of green algae physiology and will be instrumental in simulating, analyzing and interpreting the underlying complex metabolic and genetic systems.

Within the research initiative in systems biology (FORSYS), three closely collaborating partners participate in the project which in consequence consists of three workpackages (WP). The experimental WP1 carried out at the Institute of General Botany and Plant Physiology headed by M. Mittag investigates techniques for improvement of photosynthetic efficiency in connection with nitrogen metabolism by considering and modulating the circadian control of these processes. The dynamic model of photosynthetic processes and the Calvin cycle in C. reinhardtii to be established in the Ebenhöh group (Max Planck Institute of Molecular Plant Physiology) can be coupled with the circadian oscillator model to be established in WP3. In WP3, we will, moreover, focus on simulating the effect of circadian rhythms on photosynthesis and nitrogen metabolism. Therefore, the cooperation will allow one to derive valuable predictions on the increase of ammonium uptake and photosynthetic productivity.



Dr. Oliver Ebenhöh
Max Planck Institute of Molecular Plant Physiology
Am Mühlenberg 1, D-14424 Potsdam-Golm
phone: +49 331 567 8630

Prof. Maria Mittag
Friedrich Schiller University Jena
Institute of General Botany and Plant Physiology
Am Planetarium 1, D-07743 Jena
phone: +49 3641 9 49201

Prof. Stefan Schuster
Friedrich Schiller University Jena
Department of Bioinformatics at Faculty of Biology and Pharmacy
Ernst-Abbe-Platz 2, D-07743 Jena
phone: +49 3641 9 46450