Fig. 1: Mff is required for MAVS-mediated antiviral signaling.
From: MAVS is energized by Mff which senses mitochondrial metabolism via AMPK for acute antiviral immunity
a, b IFN-β (a) and IL-6 (b) secretion in WT and Mff KO MEFs. Cells were transfected with poly(I:C)-LMW (WT, KO: n = 6, 5 in a; n = 6 in b), poly(I:C)-HMW (n = 8), or poly(dI:dC) (WT, KO: n = 4, 5 in a; n = 8 in b), or cultured with LPS or palmitate (n = 6) for 8 h. P values; two-tailed unpaired t test. c Scheme of the innate immune cascades examined in this study. Defects of innate immune response were observed around MAVS under Mff deficiency. d–f qRT-PCR analyses of IFN-β (d), IL-6 (e), and IFN-α (f) mRNA in WT and Mff KO MEFs transfected with poly(I:C)-LMW (1 μg/mL) for the indicated times. P values; two-tailed unpaired t test (n = 3). The blue shaded parts of the graphs (0–8 h) represent the acute phase after poly(I:C), and the red shaded parts (8–24 h) represent the tolerant phase. g–j Immunoblot analyses of IRF3, TBK1 (g) and NF-κB (h) phosphorylation as in d–f. Phosphorylation levels of IRF3 and TBK1 were normalized to its total protein levels. P values; two-tailed unpaired t test (2–24 h; n = 3) or Mann–Whitney’s U test (0 h; n = 4). k, l qRT-PCR analysis of IFN-β mRNA in WT and Mff KO HeLa cells (k) or in HeLa cells transfected with control, Mff, MAVS, or Drp1 siRNA (l). Cells were transfected with poly(I:C)-LMW (1 μg/mL) for the indicated times. The protein levels of Mff and other RNAi genes were analyzed by immunoblotting. P values; two-tailed unpaired t test (k, n = 6; l, Control, Mff, MAVS, Drp1: n = 6, 6, 3, 3). m qRT-PCR analysis of IFN-β mRNA in WT HeLa and Mff KO HeLa cells transfected with empty vector or HA-tagged MAVS. P values; two-tailed unpaired t test (n = 4). Overexpressed MAVS protein was detected by immunoblotting. n IFN-β secretion in WT and Mff KO MEFs infected with Sendai virus (SeV) at 10 and 24 h post infection (p.i.). P values; two-tailed unpaired t test (n = 3). Data represent means ± SEM from three independent experiments (a, b, d–f, i, j–m) or representative one experiment (n) with similar results. Immunoblot analyses were repeated independently three times with similar results. Source data are provided as a Source data file.
