Treatment with G3Ia and G3Ib rapidly dissolves pre-formed stress granules. (A) Representative images of G3BP1-GFP signal in U2OS cells following induction of stress by 250 μM NaAsO₂. Images are shown 30 min after induction of stress (immediately before the addition of compound), 32 min after induction of stress (2 min after addition of 50 μM G3I compound), and 40 min after induction of stress (10 min after addition of 50 μM G3I compound). Scale bar, 40 μm. (B) Quantification of cells as in A showing the percentage of stress granule area per cell. (C) Quantification of the percentage of stress granule area per cell throughout heat shock (43°C, 30 min) and recovery (37°C) from U2OS cells stably expressing G3BP1-GFP. Cells were treated with 50 μM G3I compound 25 min after the induction of heat shock. (D) Schematic showing the experimental paradigm used in E and F. U2OS cells stably expressing G3BP1-GFP were exposed to 250 μM NaAsO₂ for 30 min followed by the addition of 50 μM G3I compound. Cells were fixed and stained 5 min after compound was added. (E and F) Shown are representative images of immunofluorescence staining of additional stress granule markers (eIF3η, PABPC1, FXR1). Scale bars, 20 μm. Error bars represent mean ± SEM in all graphs.