Prof. Dr. Andreas Hiltbrunner (CIBSS-AI), Institute of Biology II, Department of Moleuclar Plant Physiology (Faculty of Biology), University of Freiburg
Plants are sessile organisms and therefore sensing and integrating signals to adapt to changes in the environment is key to survival. Liquid-liquid phase separation (LLPS) is emerging as an important process in signalling and signal integration. In plants, several membrane-less compartments in the cytosol or the nucleus are possibly formed by LLPS. The function of these compartments is still unclear but they may play a role in diverse signalling pathways, including responses to the phytohormones auxin and ethylene, hypoxia or light. Phytochromes are photoreceptors that allow plants to sense and adapt to the light environment. Sequestered areas of phytochrome (SAPs) and p-bodies in the cytosol, and photobodies in the nucleus are membrane-less compartments regulated by phytochromes. In previous research, we identified factors that control the stability of photobodies and we recently have shown that phytochromes promote the disassembly of p-bodies. Transcripts encoding proteins with a function in auxin- or ethylene-dependent development are stored in p-bodies and light induced release of such mRNAs is a potential molecular mechanism for the integration of light and hormone signalling. Here, we want to purify different membrane-less compartments to identify their composition and function, and elucidate the molecular mechanism by which light controls these signalling assemblies.