Molecular mechanisms of physiological and aberrant phase transitions
The Alberti and Seidel teams will join forces to investigate the conformational dynamics of Fused in Sarcom (FUS) in vitro and in living cells using cutting-edge single molecule technology such as Förster energy transfer (FRET), fluorescence correlation spectroscopy (FCS) and integrative FRET-restrained structural modelling. We aim to characterize the conformational dynamics of FUS in the four different material states in vitro (soluble, liquid droplet, gel, fiber). We will then determine how the structure and dynamics of FUS is affected by RNA and protein binding partners. Next, we will compare the conformational dynamics of FUS in vitro with those in vivo in the nucleus, cytoplasm, and in physiological and aberrant condensates. Finally, we will generate FUS variants with specific defects in phase separation behavior and test these variants in living cells to gain insight into physiology and disease mechanisms. In summary, we aim to uncover the molecular events underlying the formation of cellular condensates, thus generating a detailed quantitative understanding of the molecular mechanisms driving phase separation in living cells.