2.6. Double-stranded RNA (dsRNA) Staining

Cells were washed with ice-cold PBS 3 times and fixed with 4% paraformaldehyde (Sigma-Aldrich) at room temperature for 15 minutes. Then, the cells were washed 3 times with ice-cold PBS and permeabilized with permeabilization buffer (PBS containing 1% Triton X-100) at room temperature for 5 minutes. The cells were then washed 3 times with ice-cold PBS and immunoblocked with blocking buffer (PBS containing 1% BSA and 0.01% Triton X-100) at 4°C for 30 minutes. Next, the cells were washed 3 times with ice-cold PBS and immunohybridized with mouse anti-dsRNA J2 primary antibody at 4°C overnight. Subsequently, the cells were washed 3 times with ice-cold PBS and stained with Alexa Fluor 488-conjugated goat anti-mouse antibody (Thermo Fisher Scientific) at room temperature for 15 minutes. The cells were washed 3 times with ice-cold PBS and then visualized with fluorescence or confocal microscopy. DAPI (Sigma-Aldrich) was used for nuclear staining.