Tracking Stress Granule Dynamics in Live Cells and <i>In Vivo</i> with a Small Molecule

Abstract

Because of the lack of facile and accurate methods to track stress granule (SG) dynamics in live cells and <i>in vivo</i>, in-depth studies of the biological roles of this attractive membraneless organelle have been limited. Herein, we report the first small-molecule probe, <b>TASG</b>, for the selective, convenient and real-time monitoring of SGs. This novel molecule can simultaneously bind to SG RNAs, the core SG protein G3BP1, and their complexes, triggering a significant enhancement in fluorescence intensity, making <b>TASG</b> broadly applicable to SG imaging under various stress conditions in fixed and live cells, <i>ex vivo</i> and <i>in vivo</i>. Using <b>TASG</b>, the complicated endogenous SG dynamics were revealed in both live cells and <i>C. elegans</i>. Collectively, our work provides an ideal probe that has thus far been absent in the field of SG investigations. We anticipate that this powerful tool may create exciting opportunities to investigate the underlying roles of SGs in different organisms.