Keynote Lecture: Illumination the plasma membrane (Prof. Dr. Julien Gronnier)

Abstract:
The plasma membrane is a dynamic molecular patchwork composed of billions of individual molecules and serves as a central hub integrating endogenous and environmental signals. Our group questions how, in space and time, signaling events are regulated within the plasma membrane during plant development and immunity. We developed long-term single molecule imaging and computational solutions enabling the quantitative analysis of dynamic changes in the motion of plasma membrane proteins at the nanoscale. By analyzing the components of a minimal leucine-rich repeat receptor kinase network, we uncovered the nanoscale spatial and temporal logic underlying the formation of receptor complexes. We showed that structural diverges in receptors' membrane-associated domain define their diffusion within the plasma membrane and condition receptor complex formation and signaling. We characterized structural components of the plasma membrane as inhibitors of the plasma membrane H+-ATPases. This in turn modulates receptor kinase signaling and paces Arabidopsis root developmental transitions -- a function we found conserved in the liverwort Marchantia polymorpha and which such predates the emergence of the root system itself. Our studies highlight the roles of the plasma membrane in the regulation and evolution of cell surface signaling.