Figure 4: DENV protease complex and its components counteract the cGAS/STING pathway. | Nature Microbiology
Evaluation of the DENV protease components as antagonists of the cGAS/STING pathway by IFN-β reporter assay. 293T reporter cells were co-transfected with plasmids encoding human cGAS, STING, plus empty vector, proteolytically inactive NS2B3 mutant (NS2B3–S135A), DENV WT protease (NS2B3 WT), NS2B or NS3 expressed individually. In every case, three different plasmids concentrations were used to evaluate a dose-dependent effect. a, The cGAS/STING pathway was activated by co-expression of the two proteins. Results are representative of two independent experiments and are expressed as mean ± s.e.m. from three biological replicates. P values: lanes 2–3, P = 0.2783; lanes 2–4, P = 0.8536; lanes 2–5, 2–6, 2–7 and 2–8, P < 0.0001; lanes 2–9, P = 0.0822; lanes 2–10, 2–11, 2–12, 2–13 and 2–14, P < 0.0001; lanes 3–6, 3–9 and 3–12, P < 0.0001; lanes 4–7, 4–10 and 4–13, P < 0.0001; lanes 5–8, 5–11 and 5–14, P < 0.0001 (one-way ANOVA). b, Infection with Sendai virus (SeV) as an inducer of the RIG-I-like receptors pathway. Results are representative of two independent experiments and are expressed as mean ± s.e.m. from three biological replicates. P values: lanes 2–3, P = 0.0022; lanes 2–4, P > 0.999; lanes 2–5, P > 0.999; lanes 2–6, P > 0.999; lanes 2–7 and 2–8, P < 0.0001; lanes 2–9, P = 0.4737; lanes 2–10, P = 0.0003; lanes 2–11, P < 0.0001; lanes 2–12, P = 0.0002; lanes 2–13 and 2–14, P < 0.0001; lanes 3–6, P = 0.0152; lanes 3–9, P = 0.4481; lanes 3–12, P < 0.0001; lanes 4–7, P < 0.0001; lanes 4–10, P = 0.0018; lanes 4–13, P < 0.0001; lanes 5–8, 5–11 and 5–14, P < 0.0001 (one-way ANOVA). NS, not significant. Protein expression control for a and b is shown. *Unspecific band. Asterisk in black represents specific P values obtained against empty vector control (lane 2 condition). Asterisk in blue represents P values obtained against the corresponding concentration of NS2B3–S135A plasmid (lanes 3 to 5 conditions).