Fig. 5. Several cancer-associated cGAS mutations abolish the repressive effect of cGAS on L1 retrotransposition.

a Schematic showing cancer-associated cGAS mutations identified through data mining of the TCGA database. b The effect of overexpressing cGAS WT and cancer-associated cGAS mutants on L1 retrotransposition efficiency. Thirty-seven cancer-associated cGAS mutants were cloned and transfected into HeLa cells for the analysis of retrotransposition efficiency. Each dot represents an independent experiment, and n = at least 3 independent experiments per group. Two-sided Student’s t-test was performed. c Comparison of ORF2p protein levels with overexpressing cGAS WT or cancer-associated cGAS mutants. Cells were transfected with the indicated cGAS WT or cGAS mutants and ORF2p-Flag and harvested for use in Western blot analysis 24 h post-transfection. d Analysis of the interaction between CHK2 and WT or mutated cGAS. Cells were transfected with the indicated plasmids and collected for co-IP experiments 24 h post-transfection. e Analysis of the association between TRIM41 and WT or mutated cGAS after DNA was damaged. The cells were transfected with the indicated plasmids and treated with 100 μg/mL etoposide for 90 min before being harvested for use in co-IP experiment 24 h post-transfection. f Analysis of the interaction between ORF2p and WT or mutated cGAS. Cells were transfected with the indicated plasmids and harvested for co-IP experiments 24 h post-transfection. g Analysis of the effect of overexpressing WT or mutated cGAS on the TRIM41-ORF2p interaction. Cells were transfected with the indicated plasmids and collected for co-IP experiments 24 h post-transfection. Data are presented as mean values ± s.d. Student’s t test was performed for (b). All the Inputs and IPs were from the same experiments. All experiments were repeated at least three times.