Fig. 7: Cellular efficacy and mechanism of action of allosteric PCIs.
From: De novo design of protein condensation inhibitors by targeting an allosteric site of cGAS
a, b Dose-dependent curves for inhibition of two compounds against h-cGASFL enzymatic activity at the molecular level measured by the PPI assay and IFN-luciferase activity assay in THP-1 Dual cells induced by HT-DNA. c IC50, EC50, IC50/EC50 ratio, and CC50 values of three compounds. d A schematic representation of the mechanism by which allosteric inhibitors effectively inhibit cGAS cellular activity. Blue circles represent LLPS droplets. The different positions of the fulcra in the two balances represent distinct leverage effects, reflecting varying efficacies of different types of cGAS inhibitors. e Synergistic effects of XL-3158 and G150 on inhibition of HT-DNA-induced IFN-luciferase activity in THP-1 Dual cells. Compounds (XL-3158: G150) were tested at molar ratios of 1:10, 1:5, 1:2.5, 1:1, 2.5:1, 5:1, and 10:1. Combination Index (CI) values were determined at the 90% effective dose (ED90) using CompuSyn software. CI < 1 indicates synergistic effects. f A schematic diagram of the DNA-induced IFN pathway activation. Inhibition of the IFN pathway is activated by different inducers in the presence of various compounds. g Quantification of IFNB-1 mRNA levels by qPCR, demonstrating the effects of compounds on the IFN pathway activation in THP-1 Dual cells induced by HT-DNA for 4 h. Statistical significance was determined by an unpaired two-tailed t test. **p < 0.01, ***p < 0.005, and ****p < 0.001. h Western blot analysis showing the effect of different concentrations of XL-3158 on HT-DNA-induced activation of TBK-1 and IRF3 phosphorylation in THP-1 Dual cells. Quantification of IFNB-1 mRNA levels by qPCR, demonstrating the effects of compounds on the IFN pathway activation in THP-1 Dual cells induced by Poly(I:C) for 4 h (i) and cGAMP for 4 h ( j). Statistical significance was determined by an unpaired two-tailed t test. *p < 0.05, ***p < 0.005, and ****p < 0.001. Representative western blot analysis demonstrating the effects of different compounds on TBK-1 phosphorylation in THP-1 Dual cells activated by Poly(I:C) for 4 h (k) and cGAMP for 2 h (l). Data are presented as mean ± SD from three independent experiments for all panels except d, f, h, k, l. Source data is available with this manuscript as a Source Data file.
