Figure 8.

USP21 negatively regulates antiviral response independent of A20 ubiquitin-editing complex. (A–D) WT, A20^−/−, ITCH^−/−, and TAXBP1^−/− MEFs were transfected with IFN-β reporter along with MYC-USP21 WT or CA mutant for 24 h, and then left uninfected or infected with SeV for 12 h before luciferase activity was measured. (E) HEK293T cells were transfected with the indicated plasmids along with IFN-β luciferase reporter for 24 h, and then infected with SeV or left untreated for 12 h before luciferase assays were performed. (F) WT, USP21^−/−, and A20^−/− MEFs were infected with SeV with the indicated time points. Cell lysates were immunoblotted by the indicated antibodies. (G) WT, USP21^−/−, and A20^−/− MEFs were infected with SeV with the indicated time points. IFN-β production was determined by ELISA kit. Error bars indicate ±SD in duplicate experiments. The data from A–G are representative of two independent experiments.