Figure 3. Zika virus (ZIKV) infection activates gasdermin E (GSDME) via extrinsic apoptotic pathway.
(A–C) JEG-3 cells were infected with ZIKV at a multiplicity of infection (MOI) of 1 followed by incubated with either 10 μM VX-765, 25 μM Z-DEVD-FMK, 25 μM Z-VAD-FMK, or 10 μM GSK872. At 24 hr post-infection, the cells were subjected to microscopy (A), cytotoxicity (n=3) (B), and Western blot analyses (C). Scale bar, 50 μm. (D–F) JEG-3 cells were infected with ZIKV at an MOI of 1 followed by incubated with either 25 μM Z-IETD-FMK or 25 μM Z-LEHD-FMK. At 24 hr post-infection, the cells were subjected to microscopy (D), cytotoxicity (n=3) (E), and Western blot analyses (F). Scale bar, 50 μm. (G–H) Caspase-1, caspase-3, and caspase-8 KO JEG-3 cells or wild-type (WT) cells were infected with ZIKV at an MOI of 1. At 24 hr post infection, LDH levels in supernatant, cell viability (n=3) (G) and cleavage of GSDME, caspase-1, caspase-3, and caspase-8 were measured in ZIKV-infected JEG-3 cells. (I–J) JEG-3 cells were mock-infected or infected with ZIKV at an MOI of 1. At 24 hr post-infection, the mRNA level of TNF-α (I) and concentration of TNF-α in the culture supernatant of JEG-3 cells (J) (n=3) were determined by RT-qPCR and enzyme-linked immunosorbent assay (ELISA), respectively. (K–L) JEG-3 cells were infected with ZIKV at an MOI of 1 followed by incubated with 2 μM R-7050. At 24 hr post-infection, the cells were subjected to cytotoxicity (n=3) (K) and Western blot analyses (L). Unpaired t-test versus mock. All data are presented as the mean ± SEM of three independent experiments, and the two-tailed unpaired Student’s t-test was used to calculate significance. **, p<0.01; ***, p<0.001; ****, p<0.0001; ns, no significance.
Figure 3—figure supplement 1. Zika virus (ZIKV) infection activates caspase-3 and caspase-8 in JEG-3 cells.
