Fig. 6. G3BP1 interacts with RIG-I.

a G3BP1 interacts with RIG-I but not with MDA5, MAVS, TBK1, or IRF3 in the overexpression system. HEK293T cells (2 × 10⁶) were transfected with the indicated plasmids (5 μg of each) for 24 h. Then Co-IP and immunoblotting analysis were performed with the indicated antibodies. b Endogenous G3BP1 interacted with RIG-I in HEK293T cells. HEK293T cells (5 × 10⁷) were uninfected or infected with SeV for the indicated time. Co-IP and immunoblotting experiments were performed with the indicated antibodies. c, d Domain identification of G3BP1 and RIG-I interaction. HEK293T cells were transfected with the expression plasmids encoding RIG-I and G3BP1 or the corresponding mutants (5 μg each) for 24 h. Co-IP and immunoblotting were performed with the indicated antibodies. e, f Effects of G3BP1 overexpression and its mutants on SeV-triggered IFN-β promoter and ISRE activation. HEK293T cells (1 × 10⁵) were transfected with the IFN-β promoter or ISRE reporter (0.1 μg) and the indicated expression plasmids (0.1 μg) for 24 h. Then cells were uninfected or infected with SeV for 12 h before luciferase assays. The experiment was repeated in triplicates. Data are mean ± SD of three independent experiments. Co-IP Co-immunoprecipitation, EV empty vector, Luc luciferase, αF anti-Flag, αH anti-HA, HC heavy chain, WT wild-type.