Journal: Scientific Reports
Article Title: TRBP modulates RLR signaling by inhibiting PKR-mediated antiviral stress granule formation
doi: 10.1038/s41598-025-07121-3
Figure Lengend Snippet: TRBP inhibits PKR activation and avSG formation. (a) Flp-In 293 CBP-SBP-GFP (GFP) or FLAG-TRBP cells were treated with doxycycline (Dox) 0 or 1.0 µg/mL for 14 h. The cells were mock-treated (mock), infected with NDV or IAVΔNS1, or transfected with polyIC. After 12 h incubation, cell extracts were prepared and subjected to SDS-PAGE, and immunoblotted using antibodies against GFP, FLAG-tag, PKR, phospho-PKR (Thr 446), eIF2α, phospho-eIF2α (Ser 51), NDV NP, IAV NP, and ACTB. The intensity of the p-PKR and p-eIF2α bands was normalized against ACTB, measured using ImageJ software. (b) Flp-In 293 FLAG-TRBP cells were treated with DOX 0 or 1.0 µg/mL for 24 h, and infected with IAVΔNS1 for 12 h. The cells were stained with anti-FLAG (Green = TRBP), anti-IAV NP (Red), anti-TIAR (Gray) antibodies, and DAPI (Blue). The white scale bar corresponds to 10 μm. The percentages of SG-containing cells were calculated in more than 10 randomly chosen fields for each slide ( n > 660 cells). (c) Flp-In 293 FLAG-TRBP cells were treated with DOX 0 or 1.0 µg/mL for 24 h, and treated with NaAsO 2 (0.5 mM) for 30 min and stained with anti-FLAG (Green = TRBP), anti-TIAR (Red) antibodies and DAPI (Blue). The white scale bar corresponds to 10 μm. The percentages of SG-containing cells were calculated in more than six randomly chosen fields for each slide ( n > 280 cells). (d) Flp-In 293 CBP-SBP-GFP (GFP) or FLAG-TRBP (TRBP) cells were transiently transfected with p-125Luc and pRL-tk reporter vectors, together with the RIG-I CARD, MAVS, and IRF-3-5D expressing vectors, respectively. After 24 h transfection, the cells were treated with DOX 0 (-) or 1.0 (+) µg/mL for 24 h and subjected to a dual-luciferase assay. Luciferase activity is normalized against each DOX (-) as 100%. At least two independent experiments represent similar results, and the bars indicate the one representative; each bar shows the means and ± the standard deviation (S.D.) of the technical triplicate. P-values were determined by Student’s t-test (* P < 0.05).
Article Snippet: Polyinosinic-polycytidylic acid (polyIC) was purchased from Amersham (UK).
Techniques: Activation Assay, Infection, Transfection, Incubation, SDS Page, FLAG-tag, Software, Staining, Expressing, Luciferase, Activity Assay, Standard Deviation