FIG 10.

TRIM21 promotes the K27-linked polyubiquitination of MAVS on Lys325 and the recruitment of TBK1 to MAVS. (A) HEK293T cells were cotransfected with the indicated plasmids for 42 h and treated with MG132 (25 μM) for an additional 6 h. Ubiquitination and immunoblotting assays were performed with the indicated antibodies. (B) HEK293T cells were cotransfected with the indicated plasmids for 42 h and treated with MG132 (25 μM) for an additional 6 h. Ubiquitination and immunoblotting assays were performed with the indicated antibodies. (C) Luciferase activity of lysates in HEK 293T cells transfected for 24 h with IFN-β–Luc or ISRE-Luc plus Myc-MAVS (WT) or Myc-MAVS (K325R), along with Flag-TRIM21 or an empty vector. (D and E) TRIM21 promoted interaction between MAVS and TBK1. HLCZ01 cells were transfected with pSilencer-vector or pSilencer-TRIM21 for 24 h and then infected with NDV (D) or SeV (E) for 16 h. IP and immunoblotting were performed with the indicated antibodies. (F) Huh7.5.1(MAVS-C508R) cells were transfected with pSilencer-vector or pSilencer-TRIM21 for 24 h and then infected with HCV (MOI = 2) for 72 h. IP and immunoblotting assays were performed with the indicated antibodies. The results are presented as means ± standard deviations. *, P < 0.05; **, P < 0.01 versus control.