Interferon-independent STING signaling promotes resistance to HSV-1 in vivo

Nat Commun. 2020 Jul 7;11(1):3382. doi: 10.1038/s41467-020-17156-x.

Abstract

The Stimulator of Interferon Genes (STING) pathway initiates potent immune responses upon recognition of DNA. To initiate signaling, serine 365 (S365) in the C-terminal tail (CTT) of STING is phosphorylated, leading to induction of type I interferons (IFNs). Additionally, evolutionary conserved responses such as autophagy also occur downstream of STING, but their relative importance during in vivo infections remains unclear. Here we report that mice harboring a serine 365-to-alanine (S365A) mutation in STING are unexpectedly resistant to Herpes Simplex Virus (HSV)-1, despite lacking STING-induced type I IFN responses. By contrast, resistance to HSV-1 is abolished in mice lacking the STING CTT, suggesting that the STING CTT initiates protective responses against HSV-1, independently of type I IFNs. Interestingly, we find that STING-induced autophagy is a CTT- and TBK1-dependent but IRF3-independent process that is conserved in the STING S365A mice. Thus, interferon-independent functions of STING mediate STING-dependent antiviral responses in vivo.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy
  • Female
  • Herpes Simplex / immunology*
  • Herpesvirus 1, Human
  • Immune Evasion
  • Interferon Regulatory Factor-3 / immunology*
  • Interferon Type I / immunology*
  • Macrophages / immunology
  • Male
  • Membrane Proteins / genetics*
  • Membrane Proteins / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Mutant Strains
  • Point Mutation
  • Signal Transduction

Substances

  • Interferon Regulatory Factor-3
  • Interferon Type I
  • Irf3 protein, mouse
  • Membrane Proteins
  • Sting1 protein, mouse