Fig. 8

Connexin 43 amplifies influenza virus-induced STING-dependent innate immune signaling. a Schematic representation of experimental setup (left panel). cGAS-293FT cells were infected with ΔNS1 influenza virus (purple). Six hours later, uninfected WT (red) or STING KO (green) HEK293FT cells were added to the ΔNS1 influenza virus-infected cGAS-293FT cells (purple) and co-cultured for additional 18 h. IFN-β mRNA levels were assessed by quantitative PCR at 24 h post infection (right panel). b cGAS-293FT cells infected with ΔNS1 influenza virus in the presence or absence of CBX (160 μM). IFN-β mRNA levels were assessed by quantitative PCR at 24 h post infection. c cGAS-293FT cells were transfected with the expression plasmid encoding HA-tagged IRF3. Twenty-four hours after transfection, the cells were infected with ΔNS1 influenza virus in the presence or absence of CBX (160 μM). Cell lysates were collected at 12 h post infection and blotted using the indicated antibodies. d Samples from cGAS-293FT cells transfected with siRNA targeting connexin 43 (CX43) or control siRNA were blotted using the indicated antibodies (left panel) or intracellularly stained with CX43-specific antibody and analyzed by flow cytometry (right panel). e Schematic representation of experimental setup (left panel). cGAS-293FT cells transfected with siRNA targeting connexin 43 (CX43) or control siRNA were infected with ΔNS1 influenza virus (purple). Six hours later, uninfected HEK293FT cells (red) were added to the ΔNS1 influenza virus-infected cGAS-293FT cells (purple) and co-cultured for additional 18 h. IFN-β mRNA levels were assessed by quantitative PCR at 24 h post infection (right panel). These data are from three independent experiments (a, b, e; mean ± s.e.m.). *P < 0.05, **P < 0.01, ***P < 0.001; (one-way ANOVA and Tukey’s test). Source data are provided as a Source Data file