Dr. Kasper van Gelderen – Centre of Organismal Studies – Heidelberg University
Plants are essential organisms, since they create sugars from light energy. Light perception is therefore very important for plants, so they have evolved photoreceptors to sense light (quality) and act upon it. We investigate the basis of plant light perception and signaling and how this is organized in the plant nucleus
Research Summary
Light perception and responses are essential for plant life and how light can be converted into a biochemical signal is a fundamental question in biology. Phytochromes are the main red light sensors in plants and phytochromes form small (~40nm) subnuclear bodies, which also contain supporting cofactors and downstream transcription factors. These subnuclear structures are called photobodies and they play an important role in regulating light responses. Importantly, phytochromeB (phyB) is not only required for light-, but also for temperature-sensing, suggesting that photobodies also play an important role for plant responses to ambient temperature. Despite their importance, it remains unclear how the formation of photobodies aids phytochrome signaling, how output specificity is achieved in response to divergent stimuli and how this information influences plant developmental decisions. The phyB photobody is also seen to be a liquid-liquid phase separated compartment, which may help light signaling processes to occur more efficiently, however this is as of yet unproven. The formation of nuclear bodies is a general process in the eukaryotic nucleus, and lessons learned from photobodies may help us understand nuclear organization in general. To tackle these fundamental questions we investigate the formation and responses of photobodies to light and temperature using an integrated approach of high resolution live imaging and biochemistry.
