Journal: The Journal of Experimental Medicine
Article Title: DNA-PK interacts with cyclic dinucleotides and inhibits type I interferon responses
doi: 10.1084/jem.20251796
Figure Lengend Snippet: DNA-PKcs dampens 2′3′-cGAMP-mediated STING signaling. (A) Graph represents mean (±SEM, n = 3 independent experiment) CXCL10 and CCL5 levels as measured in supernatant of T98G cells treated or not with 2 µM NU7441 for 1 h prior to transfection or not of 10 µg/ml 2′3′-cGAMP for 6 h. Statistical significance was calculated by two-tailed Student's t test. (B) T98G cells were pretreated with the NU7441 (2 µM), NU7026 (10 µM), and AZD7648 (5 µM) DNA-PKcs inhibitors for 1 h prior to transfection of 2′3′-cGAMP (10 µg/ml) for 6 h and gene expression analysis. Graphs present the mean (±SEM, n = 3 independent experiments). Statistical significance was calculated by two-tailed Student's t test. (C) T98G cells were pretreated with the NU7441 (2 µM) for 1 h prior to transfection with dsDNA (2 µg) for 6 h and gene expression analysis. Graphs present the mean (±SEM, n = 3 independent experiments). Statistical significance was calculated by two-tailed Student's t test. (D) T98G cells were transfected for DNA-PKcs– or KU70-targeting siRNAs or a control nontargeting siRNA for 48 h prior to analysis of knockdown efficiency by WB using the indicated antibodies. Representative WB; n = 3 independent experiments. (E) T98G cells were engineered to express control nontargeting or PRKDC-targeting gRNA. Representative WB; n = 3 independent experiments. (F) THP-1 CTRL, THP1 cGAS−/− , and THP1 STING−/− were pretreated or not with the NU7441 (2 µM) inhibitor for 1 h prior to transfection or not of 2′3′-cGAMP (10 µg/ml) for 6 h. WB analysis was performed using the indicated antibodies. Representative WB of three to five independent experiments. (G) Densitometric quantification of band intensities of the p-IRF3/IRF3 ratio from the WB in F. Results shown as % of induction of 2′3′-cGAMP response ( n = 3–5 independent experiments). (H) Densitometric quantification of band intensities of the pSTING/STING ratio from the WB in F. Results shown as % of induction of 2′3′-cGAMP response ( n = 3–5 independent experiments). (I) Graph represents mean (±SEM, n = 3 independent experiment) IFNβ levels as measured in supernatant of THP1 CTRL , THP1 cGAS−/− , and THP1 STING−/− pretreated or not with the NU7441 (2 µM) inhibitor for 1 h prior to transfection or not of 2′3′-cGAMP (10 µg/ml) for 6 h. Statistical significance was calculated by two-tailed Student's t test. (J) T98G cells were engineered to express control nontargeting or PRKDC-targeting gRNA. Representative WB of three independent experiments. (K) T98G cells engineered to express control nontargeting or STING-targeting gRNAs were treated or not with 2 µM of NU7441 prior to transfection or not of 10 µg/ml 2′3′-cGAMP and gene expression analysis. Graphs present the mean (±SEM, n = 5 independent experiments). Statistical significance was calculated by two-tailed Student's t test. (L) As in K, except that WB analysis was performed using the indicated antibodies. Representative WB of three independent experiments. (M) As in L, except that T98G cells expressing an IFNAR-targeting gRNA were used. Representative WB of three independent experiments. (N) THP-1 cells were pretreated or not with the NU7441 (2 µM) inhibitor for 1 h prior to transfection with dsDNA (2 µg) for up to 24 h. Gene expression analysis was conducted at 3, 6, 16, and 24 h. Graphs present the mean (±SEM, n = 3 independent experiments). Statistical significance was calculated by two-tailed Student's t test. (O) Cell culture supernatants were collected at 24 h in experiment performed as in N, and cytokine/chemokine levels were analyzed using a proteome profiler array. Heatmap representation of relative spot intensities is shown (mean of three independent experiments). (P) STING-deficient THP-1 cells engineered to express human STING haplotypes (STING-H232, STING-AQ, and STING-HAQ) were pretreated or not with the NU7441 (2 µM) for 1 h prior to transfection of 2′3′-cGAMP (10 µg/ml) for 6 h and gene expression analysis. Graphs present the mean (±SEM, n = 3 independent experiments). Statistical significance was calculated by two-tailed Student's t test. (Q) As in P, except that IFNβ and CXCL10 levels were quantified by ELISA in supernatants. Graphs present the mean (±SEM, n = 3 independent experiments). Statistical significance was calculated by two-tailed Student's t test. ****: P < 0.0001; ***: P < 0.001; **: P < 0.01; *: P < 0.05; ns, not significant. Related to . Source data are available for this figure: .
Article Snippet: To generate the T98G IFNAR−/− knockout and control cell lines, lentiviral particles were produced by co-transfection of 2 × 10 6 293T cells with 5 μg of LentiCRISPRv2GFP plasmid (#82416; Addgene) expressing the gRNA targeting the gene of interest or nontargeting control gRNA, 5 μg of psPAX2, and 1 μg of pMD2.G, using the standard calcium phosphate transfection protocol.
Techniques: Transfection, Two Tailed Test, Gene Expression, Control, Knockdown, Expressing, Cell Culture, Enzyme-linked Immunosorbent Assay