Fig. 2: STAT1 and STAT2 play an antiviral role in bats.

A PaKiT03, Efk3B, A549, and RPTEC cells were treated with vehicle or species-matched IFNβ (10 U/mL) for 5, 10, and 20 min. Total STAT1, STAT2, and phosphorylated STAT1 (pY701-STAT1) and STAT2 (pY690-STAT2) levels were assessed by immunoblotting. GAPDH was used as a loading control. Full blots can be found in Supplementary Fig. 4. B PaKiT03, Efk3B, A549, and RPTEC cells were treated for 5, 10, and 20 min with species-matched IFNβ (10 U/mL). Cells were fixed and stained for pY701-STAT1, pY690-STAT2, STAT2, and nucleus (DAPI). Nuclear translocation was visualized by confocal microscopy and quantified using ImageJ. Data were presented as mean ± SD, n = 3 biological replicates, where three fields of view were quantified per time point. Bat and human icons were obtained from BioRender [https://BioRender.com/o9oes1x]. C PaKiT03, Efk3B, A549, and RPTEC cells were pretreated for 48 h with siRNA targeting STAT1 and STAT2 individually or in combination (DKD). Cells were then treated for 6 h with species-matched IFNβ (10 U/mL), followed by infection with VSV-GFP (MOI 0.1) for 16 h. Viral infection was visualized by fluorescent microscopy, and D quantified using ImageJ. Scale bars = 100 µm. Data in panel D are presented as mean ± SD, n = 3 biological replicates. E PaKiT03, Efk3B, Huh7, and RPTEC cells were pretreated with species-matched IFNβ for 6 h prior to infection or received IFNβ treatment following infection with MERS-CoV (MOI 0.1) for 48 h. Protein lysate was harvested and probed using immunoblots for total STAT1 and STAT2, pY701-STAT1, pY690-STAT2, MERS-CoV nucleoprotein (N), GAPDH, and ACTB. Full blots can be found in Supplementary Fig. 8.