FIG 2.

ZIKV inhibits SG formation induced by multiple stress stimuli. (A) A549 cells were infected with ZIKV (MOI of 3) for 24 h. Cells were then treated with 0.5 mM sodium arsenite (Arsenite) for 30 min, 1 μM hippuristanol (Hipp) for 25 min, or dimethyl sulfoxide (DMSO) (vehicle control) or were transfected with 0.5 μg of poly(I·C) for 10 h and then processed for confocal microscopy. Infected cells were detected with mouse antibodies to flavivirus E protein or dsRNA. SGs were identified using rabbit anti-G3BP1 and goat anti-TIA-1. Primary antibodies were detected with donkey anti-rabbit IgG conjugated to Alexa Fluor 488, donkey anti-mouse IgG conjugated to Alexa Fluor 546, and chicken anti-goat IgG conjugated to Alexa Fluor 647. Nuclei were stained with DAPI. Images were acquired using a spinning-disc confocal microscope. Size bar, 22 μm. (C) Primary human fetal astrocytes were infected with ZIKV (MOI of 5) for 48 h, left untreated or treated with sodium arsenite (0.5 mM) for 30 min, and processed for confocal microscopy. Infected cells were detected with mouse antibodies to flavivirus E protein. SGs were identified using rabbit anti-G3BP1 and goat anti-TIA-1. (B and D) Quantification of SGs was performed using Volocity software. A minimum of 30 cells was used for each sample. Values are the average number of SGs per cell ± standard errors from three independent experiments. P values were determined by Student's t test. *, P < 0.05 (significant).