Abstract
AbstractStress granules (SGs) are membraneless organelles composed of various proteins and RNAs that protect translation-associated machinery from harmful conditions during stress. However, the functional differences among SG compartments remain unclear. Here, we show that the spatial and temporal control of SG subcompartments by chromophore-associated light inactivation (CALI) using a genetically encoded red fluorescence protein (SuperNova-Red) as a photosensitizer leads to differences in cell viability during recovery from hyperosmotic stress and that the inactivation of the core phase in SGs could be more critical than the shell phase. CALI delayed the disassembly kinetics of SGs during recovery from hyperosmotic stress. Consequently, CALI could inactivate the subcompartments of SGs, and the cellular fate due to SGs could be analyzed. Furthermore, CALI is an effective spatiotemporal knockdown method for intracellular condensates/aggregates and contributes to the elucidation of membraneless organelles.
Publisher
Cold Spring Harbor Laboratory