Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Review Article
  • Published:

Molecular mechanisms and cellular functions of cGAS–STING signalling

Abstract

The cGAS–STING signalling axis, comprising the synthase for the second messenger cyclic GMP–AMP (cGAS) and the cyclic GMP–AMP receptor stimulator of interferon genes (STING), detects pathogenic DNA to trigger an innate immune reaction involving a strong type I interferon response against microbial infections. Notably however, besides sensing microbial DNA, the DNA sensor cGAS can also be activated by endogenous DNA, including extranuclear chromatin resulting from genotoxic stress and DNA released from mitochondria, placing cGAS–STING as an important axis in autoimmunity, sterile inflammatory responses and cellular senescence. Initial models assumed that co-localization of cGAS and DNA in the cytosol defines the specificity of the pathway for non-self, but recent work revealed that cGAS is also present in the nucleus and at the plasma membrane, and such subcellular compartmentalization was linked to signalling specificity of cGAS. Further confounding the simple view of cGAS–STING signalling as a response mechanism to infectious agents, both cGAS and STING were shown to have additional functions, independent of interferon response. These involve non-catalytic roles of cGAS in regulating DNA repair and signalling via STING to NF-κB and MAPK as well as STING-mediated induction of autophagy and lysosome-dependent cell death. We have also learnt that cGAS dimers can multimerize and undergo liquid–liquid phase separation to form biomolecular condensates that could importantly regulate cGAS activation. Here, we review the molecular mechanisms and cellular functions underlying cGAS–STING activation and signalling, particularly highlighting the newly emerging diversity of this signalling pathway and discussing how the specificity towards normal, damage-induced and infection-associated DNA could be achieved.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Overview of canonical cGAS–STING signalling.
Fig. 2: Cellular localization and DNA ligands of cGAS.
Fig. 3: Mechanism of cGAS activation.
Fig. 4: Mechanism of STING activation.
Fig. 5: Effector functions of STING.

Similar content being viewed by others

References

  1. Rotem, Z., Cox, R. A. & Isaacs, A. Inhibition of virus multiplication by foreign nucleic acid. Nature 197, 564–566 (1963).

    Article  CAS  PubMed  Google Scholar 

  2. Stetson, D. B. & Medzhitov, R. Recognition of cytosolic DNA activates an IRF3-dependent innate immune response. Immunity 24, 93–103 (2006).

    Article  CAS  PubMed  Google Scholar 

  3. Sun, L., Wu, J., Du, F., Chen, X. & Chen, Z. J. Cyclic GMP–AMP synthase is a cytosolic DNA sensor that activates the type I interferon pathway. Science 339, 786–791 (2013). This landmark study describes the discovery and tour de force biochemical isolation of cGAS.

    Article  CAS  PubMed  Google Scholar 

  4. Wu, J. et al. Cyclic GMP–AMP is an endogenous second messenger in innate immune signaling by cytosolic DNA. Science 339, 826–830 (2013).

    Article  CAS  PubMed  Google Scholar 

  5. Kuchta, K., Knizewski, L., Wyrwicz, L. S., Rychlewski, L. & Ginalski, K. Comprehensive classification of nucleotidyltransferase fold proteins: identification of novel families and their representatives in human. Nucleic Acids Res. 37, 7701–7714 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Zhang, X. et al. Cyclic GMP–AMP containing mixed phosphodiester linkages is an endogenous high-affinity ligand for STING. Mol. Cell 51, 226–235 (2013).

    Article  CAS  PubMed  Google Scholar 

  7. Ablasser, A. et al. cGAS produces a 2′–5′-linked cyclic dinucleotide second messenger that activates STING. Nature 498, 380–384 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Gao, P. et al. Cyclic [G(2′,5′)pA(3′,5′)p] is the metazoan second messenger produced by DNA-activated cyclic GMP–AMP synthase. Cell 153, 1094–1107 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Diner, E. J. et al. The innate immune DNA sensor cGAS produces a noncanonical cyclic dinucleotide that activates human STING. Cell Rep. 3, 1355–1361 (2013). Together with references 6–8, this work establishes that cGAS catalyses a cGAMP molecule with a mixed 2′–5′, 3′–5′ phosphodiester bond.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Burdette, D. L. et al. STING is a direct innate immune sensor of cyclic di-GMP. Nature 478, 515–518 (2011). This paper establishes STING as a direct receptor for cyclic dinucleotides.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Ishikawa, H. & Barber, G. N. STING is an endoplasmic reticulum adaptor that facilitates innate immune signalling. Nature 455, 674–678 (2008). This study establishes STING as an essential component of intracellular DNA recognition.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Gao, D. et al. Activation of cyclic GMP–AMP synthase by self-DNA causes autoimmune diseases. Proc. Natl Acad. Sci. USA 112, E5699–E5705 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Gray, E. E., Treuting, P. M., Woodward, J. J. & Stetson, D. B. Cutting edge: cGAS is required for lethal autoimmune disease in the Trex1-deficient mouse model of Aicardi–Goutieres syndrome. J. Immunol. 195, 1939–1943 (2015).

    Article  CAS  PubMed  Google Scholar 

  14. Gall, A. et al. Autoimmunity initiates in nonhematopoietic cells and progresses via lymphocytes in an interferon-dependent autoimmune disease. Immunity 36, 120–131 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Ablasser, A. et al. TREX1 deficiency triggers cell-autonomous immunity in a cGAS-dependent manner. J. Immunol. 192, 5993–5997 (2014).

    Article  CAS  PubMed  Google Scholar 

  16. Corrales, L. et al. Direct activation of STING in the tumor microenvironment leads to potent and systemic tumor regression and immunity. Cell Rep. 11, 1018–1030 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Banani, S. F., Lee, H. O., Hyman, A. A. & Rosen, M. K. Biomolecular condensates: organizers of cellular biochemistry. Nat. Rev. Mol. Cell Biol. 18, 285–298 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Kranzusch, P. J. et al. Ancient origin of cGAS–STING reveals mechanism of universal 2′,3′ cGAMP signaling. Mol. Cell 59, 891–903 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Zhong, B. et al. The adaptor protein MITA links virus-sensing receptors to IRF3 transcription factor activation. Immunity 29, 538–550 (2008).

    Article  CAS  PubMed  Google Scholar 

  20. Jin, L. et al. MPYS, a novel membrane tetraspanner, is associated with major histocompatibility complex class II and mediates transduction of apoptotic signals. Mol. Cell Biol. 28, 5014–5026 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Sun, W. et al. ERIS, an endoplasmic reticulum IFN stimulator, activates innate immune signaling through dimerization. Proc. Natl Acad. Sci. USA 106, 8653–8658 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Ishikawa, H., Ma, Z. & Barber, G. N. STING regulates intracellular DNA-mediated, type I interferon-dependent innate immunity. Nature 461, 788–792 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Abe, T. et al. STING recognition of cytoplasmic DNA instigates cellular defense. Mol. Cell 50, 5–15 (2013).

    Article  CAS  PubMed  Google Scholar 

  24. Kranzusch, P. J. cGAS and CD-NTase enzymes: structure, mechanism, and evolution. Curr. Opin. Struct. Biol. 59, 178–187 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Whiteley, A. T. et al. Bacterial cGAS-like enzymes synthesize diverse nucleotide signals. Nature 567, 194–199 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Cohen, D. et al. Cyclic GMP–AMP signalling protects bacteria against viral infection. Nature 574, 691–695 (2019).

    Article  CAS  PubMed  Google Scholar 

  27. Schoggins, J. W. et al. A diverse range of gene products are effectors of the type I interferon antiviral response. Nature 472, 481–485 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Kranzusch, P. J., Lee, A. S., Berger, J. M. & Doudna, J. A. Structure of human cGAS reveals a conserved family of second-messenger enzymes in innate immunity. Cell Rep. 3, 1362–1368 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Civril, F. et al. Structural mechanism of cytosolic DNA sensing by cGAS. Nature 498, 332–337 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Li, X. et al. Cyclic GMP–AMP synthase is activated by double-stranded DNA-induced oligomerization. Immunity 39, 1019–1031 (2013).

    Article  CAS  PubMed  Google Scholar 

  31. Zhang, X. et al. The cytosolic DNA sensor cGAS forms an oligomeric complex with DNA and undergoes switch-like conformational changes in the activation loop. Cell Rep. 6, 421–430 (2014). Together with reference 30, this work provides evidence that the active form of cGAS is a dimer.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Andreeva, L. et al. cGAS senses long and HMGB/TFAM-bound U-turn DNA by forming protein–DNA ladders. Nature 549, 394–398 (2017). This structural and biochemical study shows a cooperativity-based mechanism for how cGAS preferentially senses long DNA.

    Article  CAS  PubMed  Google Scholar 

  33. Hooy, R. M. & Sohn, J. The allosteric activation of cGAS underpins its dynamic signaling landscape. eLife 7, e39984 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  34. Orzalli, M. H. et al. cGAS-mediated stabilization of IFI16 promotes innate signaling during herpes simplex virus infection. Proc. Natl Acad. Sci. USA 112, E1773–E1781 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Yang, H., Wang, H., Ren, J., Chen, Q. & Chen, Z. J. cGAS is essential for cellular senescence. Proc. Natl Acad. Sci. USA 114, E4612–E4620 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  36. Zierhut, C. et al. The cytoplasmic DNA sensor cGAS promotes mitotic cell death. Cell 178, 302–315.e23 (2019). This work establishes that cGAS binds nucleosomes in an inactive state.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  37. Liu, H. et al. Nuclear cGAS suppresses DNA repair and promotes tumorigenesis. Nature 563, 131–136 (2018).

    Article  CAS  PubMed  Google Scholar 

  38. Jiang, H. et al. Chromatin-bound cGAS is an inhibitor of DNA repair and hence accelerates genome destabilization and cell death. EMBO J. 38, e102718 (2019). Together with reference 37, this work uncovers nuclear functions of cGAS in inhibiting homologous recombination.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  39. Gentili, M. et al. The N-terminal domain of cGAS determines preferential association with centromeric DNA and innate immune activation in the nucleus. Cell Rep. 26, 2377–2393.e13 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Volkman, H. E., Cambier, S., Gray, E. E. & Stetson, D. B. Tight nuclear tethering of cGAS is essential for preventing autoreactivity. eLife 8, e47491 (2019). This paper indicates that cGAS is predominantly nuclear and tethered to chromatin via a basic patch on the catalytic domain.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Barnett, K. C. et al. Phosphoinositide interactions position cGAS at the plasma membrane to ensure efficient distinction between self- and viral DNA. Cell 176, 1432–1446.e11 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Luecke, S. et al. cGAS is activated by DNA in a length-dependent manner. EMBO Rep. 18, 1707–1715 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Herzner, A. M. et al. Sequence-specific activation of the DNA sensor cGAS by Y-form DNA structures as found in primary HIV-1 cDNA. Nat. Immunol. 16, 1025–1033 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Mankan, A. K. et al. Cytosolic RNA:DNA hybrids activate the cGAS–STING axis. EMBO J. 33, 2937–2946 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Li, X. D. et al. Pivotal roles of cGAS–cGAMP signaling in antiviral defense and immune adjuvant effects. Science 341, 1390–1394 (2013).

    Article  CAS  PubMed  Google Scholar 

  46. Gao, D. et al. Cyclic GMP–AMP synthase is an innate immune sensor of HIV and other retroviruses. Science 341, 903–906 (2013).

    Article  CAS  PubMed  Google Scholar 

  47. Paijo, J. et al. cGAS senses human cytomegalovirus and induces type I interferon responses in human monocyte-derived cells. PLOS Pathog. 12, e1005546 (2016).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  48. Lio, C. W. et al. cGAS–STING signaling regulates initial innate control of cytomegalovirus infection. J. Virol. 90, 7789–7797 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Ahlers, L. R., Bastos, R. G., Hiroyasu, A. & Goodman, A. G. Invertebrate iridescent virus 6, a DNA virus, stimulates a mammalian innate immune response through RIG-I-like receptors. PLOS ONE 11, e0166088 (2016).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  50. Zhang, Y. et al. The DNA sensor, cyclic GMP–AMP synthase, is essential for induction of IFN-β during Chlamydia trachomatis infection. J. Immunol. 193, 2394–2404 (2014).

    Article  CAS  PubMed  Google Scholar 

  51. Watson, R. O. et al. The cytosolic sensor cGAS detects mycobacterium tuberculosis DNA to induce type I interferons and activate autophagy. Cell Host Microbe 17, 811–819 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Collins, A. C. et al. Cyclic GMP–AMP synthase is an innate immune DNA sensor for Mycobacterium tuberculosis. Cell Host Microbe 17, 820–828 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  53. Wassermann, R. et al. Mycobacterium tuberculosis differentially activates cGAS- and inflammasome-dependent intracellular immune responses through ESX-1. Cell Host Microbe 17, 799–810 (2015).

    Article  CAS  PubMed  Google Scholar 

  54. Storek, K. M., Gertsvolf, N. A., Ohlson, M. B. & Monack, D. M. cGAS and Ifi204 cooperate to produce type I IFNs in response to Francisella infection. J. Immunol. 194, 3236–3245 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  55. Hansen, K. et al. Listeria monocytogenes induces IFNβ expression through an IFI16-, cGAS- and STING-dependent pathway. EMBO J. 33, 1654–1666 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  56. Andrade, W. A. et al. Type I interferon induction by Neisseria gonorrhoeae: dual requirement of cyclic GMP–AMP synthase and Toll-like receptor 4. Cell Rep. 15, 2438–2448 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  57. Webster, S. J. et al. Detection of a microbial metabolite by STING regulates inflammasome activation in response to Chlamydia trachomatis infection. PLOS Pathog. 13, e1006383 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  58. Woodward, J. J., Iavarone, A. T. & Portnoy, D. A. c-di-AMP secreted by intracellular Listeria monocytogenes activates a host type I interferon response. Science 328, 1703–1705 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  59. Hahn, W. O. et al. cGAS-mediated control of blood-stage malaria promotes plasmodium-specific germinal center responses. JCI Insight 3, e94142 (2018).

    Article  PubMed Central  Google Scholar 

  60. Lahaye, X. et al. NONO detects the nuclear HIV capsid to promote cGAS-mediated innate immune activation. Cell 175, 488–501.e22 (2018).

    Article  CAS  PubMed  Google Scholar 

  61. Yoh, S. M. et al. PQBP1 is a proximal sensor of the cGAS-dependent innate response to HIV-1. Cell 161, 1293–1305 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  62. Liu, Z. S. et al. G3BP1 promotes DNA binding and activation of cGAS. Nat. Immunol. 20, 18–28 (2019).

    Article  CAS  PubMed  Google Scholar 

  63. Lian, H. et al. ZCCHC3 is a co-sensor of cGAS for dsDNA recognition in innate immune response. Nat. Commun. 9, 3349 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  64. Morchikh, M. et al. HEXIM1 and NEAT1 long non-coding RNA form a multi-subunit complex that regulates DNA-mediated innate immune response. Mol. Cell 67, 387–399.e5 (2017).

    Article  CAS  PubMed  Google Scholar 

  65. Nandakumar, R. et al. Intracellular bacteria engage a STING–TBK1–MVB12b pathway to enable paracrine cGAS–STING signalling. Nat. Microbiol. 4, 701–713 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  66. Diamond, J. M. et al. Exosomes shuttle TREX1-sensitive IFN-stimulatory dsDNA from irradiated cancer cells to DCs. Cancer Immunol. Res. 6, 910–920 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Deng, L. et al. STING-dependent cytosolic DNA sensing promotes radiation-induced type I interferon-dependent antitumor immunity in immunogenic tumors. Immunity 41, 843–852 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  68. Xu, M. M. et al. Dendritic cells but not macrophages sense tumor mitochondrial DNA for cross-priming through signal regulatory protein α signaling. Immunity 47, 363–373.e5 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  69. Marcus, A. et al. Tumor-derived cGAMP triggers a STING-mediated interferon response in non-tumor cells to activate the NK cell response. Immunity 49, 754–763.e4 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  70. West, A. P. et al. Mitochondrial DNA stress primes the antiviral innate immune response. Nature 520, 553–557 (2015).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  71. Riley, J. S. et al. Mitochondrial inner membrane permeabilisation enables mtDNA release during apoptosis. EMBO J. 37, e99238 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  72. Rongvaux, A. et al. Apoptotic caspases prevent the induction of type I interferons by mitochondrial DNA. Cell 159, 1563–1577 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  73. White, M. J. et al. Apoptotic caspases suppress mtDNA-induced STING-mediated type I IFN production. Cell 159, 1549–1562 (2014). Together with references 70 and 72, this work provides evidence that cGAS can sense mitochondrial DNA under certain conditions.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  74. Sun, B. et al. Dengue virus activates cGAS through the release of mitochondrial DNA. Sci. Rep. 7, 3594 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  75. Aguirre, S. & Fernandez-Sesma, A. Collateral damage during dengue virus infection: making sense of DNA by cGAS. J. Virol. 91, e01081-16 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  76. Schoggins, J. W. et al. Pan-viral specificity of IFN-induced genes reveals new roles for cGAS in innate immunity. Nature 505, 691–695 (2014).

    Article  CAS  PubMed  Google Scholar 

  77. Ni, G., Ma, Z. & Damania, B. cGAS and STING: at the intersection of DNA and RNA virus-sensing networks. PLOS Pathog. 14, e1007148 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  78. Aarreberg, L. D. et al. Interleukin-1β induces mtDNA release to activate innate immune signaling via cGAS–STING. Mol. Cell 74, 801–815.e6 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  79. Mackenzie, K. J. et al. cGAS surveillance of micronuclei links genome instability to innate immunity. Nature 548, 461–465 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  80. Gluck, S. et al. Innate immune sensing of cytosolic chromatin fragments through cGAS promotes senescence. Nat. Cell Biol. 19, 1061–1070 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  81. Harding, S. M. et al. Mitotic progression following DNA damage enables pattern recognition within micronuclei. Nature 548, 466–470 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  82. Dou, Z. et al. Cytoplasmic chromatin triggers inflammation in senescence and cancer. Nature 550, 402–406 (2017). Together with references 35 and 79–81, this work describes sensing of chromatin in the cytoplasm and micronuclei by cGAS and its links to inflammation and cellular senescence.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  83. Gratia, M. et al. Bloom syndrome protein restrains innate immune sensing of micronuclei by cGAS. J. Exp. Med. 216, 1199–1213 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  84. Hatch, E. M., Fischer, A. H., Deerinck, T. J. & Hetzer, M. W. Catastrophic nuclear envelope collapse in cancer cell micronuclei. Cell 154, 47–60 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  85. Ivanov, A. et al. Lysosome-mediated processing of chromatin in senescence. J. Cell Biol. 202, 129–143 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  86. Dou, Z. et al. Autophagy mediates degradation of nuclear lamina. Nature 527, 105–109 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  87. Lan, Y. Y. et al. Extranuclear DNA accumulates in aged cells and contributes to senescence and inflammation. Aging Cell 18, e12901 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  88. Prata, L., Ovsyannikova, I. G., Tchkonia, T. & Kirkland, J. L. Senescent cell clearance by the immune system: emerging therapeutic opportunities. Semin. Immunol. 40, 101275 (2019).

    Article  CAS  Google Scholar 

  89. Chen, Y. A. et al. Extrachromosomal telomere repeat DNA is linked to ALT development via cGAS–STING DNA sensing pathway. Nat. Struct. Mol. Biol. 24, 1124–1131 (2017).

    Article  CAS  PubMed  Google Scholar 

  90. Nassour, J. et al. Autophagic cell death restricts chromosomal instability during replicative crisis. Nature 565, 659–663 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  91. Barroso-Gonzalez, J. et al. RAD51AP1 is an essential mediator of alternative lengthening of telomeres. Mol. Cell 76, 11–26.e7 (2019).

    Article  CAS  PubMed  Google Scholar 

  92. Mackenzie, K. J. et al. Ribonuclease H2 mutations induce a cGAS/STING-dependent innate immune response. EMBO J. 35, 831–844 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  93. Reislander, T. et al. BRCA2 abrogation triggers innate immune responses potentiated by treatment with PARP inhibitors. Nat. Commun. 10, 3143 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  94. Heijink, A. M. et al. BRCA2 deficiency instigates cGAS-mediated inflammatory signaling and confers sensitivity to tumor necrosis factor-α-mediated cytotoxicity. Nat. Commun. 10, 100 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  95. Wang, Z. et al. cGAS/STING axis mediates a topoisomerase II inhibitor-induced tumor immunogenicity. J. Clin. Invest. 130, 4850–4862 (2019).

    Article  Google Scholar 

  96. Luthra, P. et al. Topoisomerase II inhibitors induce DNA damage-dependent interferon responses circumventing ebola virus immune evasion. mBio 8, e00368-17 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  97. Pantelidou, C. et al. PARP inhibitor efficacy depends on CD8+ T-cell recruitment via intratumoral STING pathway activation in BRCA-deficient models of triple-negative breast cancer. Cancer Discov. 9, 722–737 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  98. Chabanon, R. M. et al. PARP inhibition enhances tumor cell-intrinsic immunity in ERCC1-deficient non-small cell lung cancer. J. Clin. Invest. 129, 1211–1228 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  99. Shen, J. et al. PARPi triggers the STING-dependent immune response and enhances the therapeutic efficacy of immune checkpoint blockade independent of BRCAness. Cancer Res. 79, 311–319 (2019).

    Article  CAS  PubMed  Google Scholar 

  100. Benitez-Guijarro, M. et al. RNase H2, mutated in Aicardi–Goutieres syndrome, promotes LINE-1 retrotransposition. EMBO J. 37, e98506 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  101. Zhou, W. et al. Structure of the human cGAS–DNA complex reveals enhanced control of immune surveillance. Cell 174, 300–311.e11 (2018). This study reports the first structure of the human cGAS–DNA complex.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  102. Du, M. & Chen, Z. J. DNA-induced liquid phase condensation of cGAS activates innate immune signaling. Science 361, 704–709 (2018). This study shows that cGAS undergoes liquid–liquid phase separation in the presence of agonistic DNA in a DNA length-dependent manner.

    Article  CAS  PubMed  Google Scholar 

  103. Xie, W. et al. Human cGAS catalytic domain has an additional DNA-binding interface that enhances enzymatic activity and liquid-phase condensation. Proc. Natl Acad. Sci. USA 116, 11946–11955 (2019). This study reveals the existence of a third DNA binding site on the cGAS catalytic domain, providing a mechanism for additional DNA–protein contacts in condensates.

    CAS  PubMed  PubMed Central  Google Scholar 

  104. Wang, C. et al. Manganese increases the sensitivity of the cGAS–STING pathway for double-stranded DNA and is required for the host defense against DNA viruses. Immunity 48, 675–687.e7 (2018).

    Article  CAS  PubMed  Google Scholar 

  105. Hooy, R. M., Massaccesi, G., Rousseau, K. E., Chattergoon, M. A. & Sohn, J. Allosteric coupling between Mn2+ and dsDNA controls the catalytic efficiency and fidelity of cGAS. Nucleic Acids Res. 48, 4435–4447 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  106. Hu, S. et al. PKR-dependent cytosolic cGAS foci are necessary for intracellular DNA sensing. Sci. Signal. 12, eaav7934 (2019).

    Article  CAS  PubMed  Google Scholar 

  107. Hall, J. et al. The catalytic mechanism of cyclic GMP–AMP synthase (cGAS) and implications for innate immunity and inhibition. Protein Sci. 26, 2367–2380 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  108. Kranzusch, P. J. et al. Structure-guided reprogramming of human cGAS dinucleotide linkage specificity. Cell 158, 1011–1021 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  109. Seo, G. J. et al. Akt kinase-mediated checkpoint of cGAS DNA sensing pathway. Cell Rep. 13, 440–449 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  110. Ning, S. & Wang, L. The multifunctional protein p62 and its mechanistic roles in cancers. Curr. Cancer Drug Targets 19, 468–478 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  111. Dai, J. et al. Acetylation blocks cGAS activity and inhibits self-DNA-induced autoimmunity. Cell 176, 1447–1460.e14 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  112. Chen, Q., Sun, L. & Chen, Z. J. Regulation and function of the cGAS–STING pathway of cytosolic DNA sensing. Nat. Immunol. 17, 1142–1149 (2016).

    Article  CAS  PubMed  Google Scholar 

  113. Hu, M. M. et al. Sumoylation promotes the stability of the DNA sensor cGAS and the adaptor STING to regulate the kinetics of response to DNA virus. Immunity 45, 555–569 (2016).

    Article  CAS  PubMed  Google Scholar 

  114. Cui, Y. et al. SENP7 potentiates cGAS activation by relieving SUMO-mediated inhibition of cytosolic DNA sensing. PLOS Pathog. 13, e1006156 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  115. Wang, Q. et al. The E3 ubiquitin ligase RNF185 facilitates the cGAS-mediated innate immune response. PLOS Pathog. 13, e1006264 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  116. Wang, Y. et al. Inflammasome activation triggers caspase-1-mediated cleavage of cGAS to regulate responses to DNA virus infection. Immunity 46, 393–404 (2017).

    Article  CAS  PubMed  Google Scholar 

  117. Ablasser, A. et al. Cell intrinsic immunity spreads to bystander cells via the intercellular transfer of cGAMP. Nature 503, 530–534 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  118. Gentili, M. et al. Transmission of innate immune signaling by packaging of cGAMP in viral particles. Science 349, 1232–1236 (2015).

    Article  CAS  PubMed  Google Scholar 

  119. Luteijn, R. D. et al. SLC19A1 transports immunoreactive cyclic dinucleotides. Nature 573, 434–438 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  120. Ritchie, C., Cordova, A. F., Hess, G. T., Bassik, M. C. & Li, L. SLC19A1 is an importer of the immunotransmitter cGAMP. Mol. Cell 75, 372–381.e5 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  121. Li, L. et al. Hydrolysis of 2′3′-cGAMP by ENPP1 and design of nonhydrolyzable analogs. Nat. Chem. Biol. 10, 1043–1048 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  122. Liu, H. et al. cGAS facilitates sensing of extracellular cyclic dinucleotides to activate innate immunity. EMBO Rep. 20, e46293 (2019).

    PubMed  PubMed Central  Google Scholar 

  123. Scully, R., Panday, A., Elango, R. & Willis, N. A. DNA double-strand break repair-pathway choice in somatic mammalian cells. Nat. Rev. Mol. Cell Biol. 20, 698–714 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  124. Wolf, C. et al. RPA and Rad51 constitute a cell intrinsic mechanism to protect the cytosol from self DNA. Nat. Commun. 7, 11752 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  125. Weitzman, M. D., Fradet-Turcotte, A. & Virus, D. N. A. Replication and the host DNA damage response. Annu. Rev. Virol. 5, 141–164 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  126. Shang, G., Zhang, C., Chen, Z. J., Bai, X. C. & Zhang, X. Cryo-EM structures of STING reveal its mechanism of activation by cyclic GMP–AMP. Nature 567, 389–393 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  127. Zhang, C. et al. Structural basis of STING binding with and phosphorylation by TBK1. Nature 567, 394–398 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  128. Shang, G. et al. Crystal structures of STING protein reveal basis for recognition of cyclic di-GMP. Nat. Struct. Mol. Biol. 19, 725–727 (2012). Together with reference 127, this work provides a mechanism for STING activation by cGAMP and STING-dependent TBK1 activation based on a structure of the transmembrane STING molecule.

    Article  CAS  PubMed  Google Scholar 

  129. Huang, Y. H., Liu, X. Y., Du, X. X., Jiang, Z. F. & Su, X. D. The structural basis for the sensing and binding of cyclic di-GMP by STING. Nat. Struct. Mol. Biol. 19, 728–730 (2012).

    Article  CAS  PubMed  Google Scholar 

  130. Yin, Q. et al. Cyclic di-GMP sensing via the innate immune signaling protein STING. Mol. Cell 46, 735–745 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  131. Ouyang, S. et al. Structural analysis of the STING adaptor protein reveals a hydrophobic dimer interface and mode of cyclic di-GMP binding. Immunity 36, 1073–1086 (2012).

    Article  CAS  PubMed  Google Scholar 

  132. Zhao, B. et al. A conserved PLPLRT/SD motif of STING mediates the recruitment and activation of TBK1. Nature 569, 718–722 (2019). This study shows at high resolution how STING interacts with and helps activate TBK1.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  133. Zhao, B. et al. Structural basis for concerted recruitment and activation of IRF-3 by innate immune adaptor proteins. Proc. Natl Acad. Sci. USA 113, E3403–E3412 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  134. Liu, S. et al. Phosphorylation of innate immune adaptor proteins MAVS, STING, and TRIF induces IRF3 activation. Science 347, aaa2630 (2015).

    Article  PubMed  CAS  Google Scholar 

  135. Ergun, S. L., Fernandez, D., Weiss, T. M. & Li, L. STING polymer structure reveals mechanisms for activation, hyperactivation, and inhibition. Cell 178, 290–301.e10 (2019).

    Article  CAS  PubMed  Google Scholar 

  136. Gui, X. et al. Autophagy induction via STING trafficking is a primordial function of the cGAS pathway. Nature 567, 262–266 (2019). This study proposes that the primordial function of STING is in regulating autophagy.

    Article  CAS  PubMed  Google Scholar 

  137. Dobbs, N. et al. STING activation by translocation from the ER is associated with infection and autoinflammatory disease. Cell Host Microbe 18, 157–168 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  138. Mukai, K. et al. Activation of STING requires palmitoylation at the Golgi. Nat. Commun. 7, 11932 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  139. Haag, S. M. et al. Targeting STING with covalent small-molecule inhibitors. Nature 559, 269–273 (2018).

    Article  CAS  PubMed  Google Scholar 

  140. de Oliveira Mann, C. C. et al. Modular architecture of the STING C-terminal tail allows interferon and NF-κB signaling adaptation. Cell Rep. 27, 1165–1175.e5 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  141. Abe, T. & Barber, G. N. Cytosolic-DNA-mediated, STING-dependent proinflammatory gene induction necessitates canonical NF-κB activation through TBK1. J. Virol. 88, 5328–5341 (2014).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  142. Fang, R. et al. NEMO-IKKβ are essential for IRF3 and NF-κB activation in the cGAS–STING pathway. J. Immunol. 199, 3222–3233 (2017).

    Article  CAS  PubMed  Google Scholar 

  143. Konno, H., Konno, K. & Barber, G. N. Cyclic dinucleotides trigger ULK1 (ATG1) phosphorylation of STING to prevent sustained innate immune signaling. Cell 155, 688–698 (2013).

    Article  CAS  PubMed  Google Scholar 

  144. Goto, A. et al. The kinase IKKβ regulates a STING- and NF-κB-dependent antiviral response pathway in Drosophila. Immunity 49, 225–234.e4 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  145. Martin, M., Hiroyasu, A., Guzman, R. M., Roberts, S. A. & Goodman, A. G. Analysis of Drosophila STING reveals an evolutionarily conserved antimicrobial function. Cell Rep. 23, 3537–3550.e6 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  146. Dunphy, G. et al. Non-canonical activation of the DNA sensing adaptor STING by ATM and IFI16 mediates NF-κB signaling after nuclear DNA damage. Mol. Cell 71, 745–760.e5 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  147. Watson, R. O., Manzanillo, P. S. & Cox, J. S. Extracellular M. tuberculosis DNA targets bacteria for autophagy by activating the host DNA-sensing pathway. Cell 150, 803–815 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  148. Dikic, I. & Elazar, Z. Mechanism and medical implications of mammalian autophagy. Nat. Rev. Mol. Cell Biol. 19, 349–364 (2018).

    Article  CAS  PubMed  Google Scholar 

  149. Liu, D. et al. STING directly activates autophagy to tune the innate immune response. Cell Death Differ. 26, 1735–1749 (2019).

    Article  CAS  PubMed  Google Scholar 

  150. Moretti, J. et al. STING senses microbial viability to orchestrate stress-mediated autophagy of the endoplasmic reticulum. Cell 171, 809–823.e13 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  151. Yamashiro, L. H. et al. STING controls herpes simplex virus in vivo independent of type I interferon induction. Preprint at bioRxiv https://doi.org/10.1101/2019.12.12.874792 (2019).

  152. Paludan, S. R., Reinert, L. S. & Hornung, V. DNA-stimulated cell death: implications for host defence, inflammatory diseases and cancer. Nat. Rev. Immunol. 19, 141–153 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  153. Gaidt, M. M. et al. The DNA inflammasome in human myeloid cells is initiated by a STING-cell death program upstream of NLRP3. Cell 171, 1110–1124.e18 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  154. Liu, Y. et al. Activated STING in a vascular and pulmonary syndrome. N. Engl. J. Med. 371, 507–518 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  155. Warner, J. D. et al. STING-associated vasculopathy develops independently of IRF3 in mice. J. Exp. Med. 214, 3279–3292 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  156. Bouis, D. et al. Severe combined immunodeficiency in stimulator of interferon genes (STING) V154M/wild-type mice. J. Allergy Clin. Immunol. 143, 712–725.e5 (2019).

    Article  CAS  PubMed  Google Scholar 

  157. Motwani, M. et al. Hierarchy of clinical manifestations in SAVI N153S and V154M mouse models. Proc. Natl Acad. Sci. USA 116, 7941–7950 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  158. Gaidt, M. M. & Hornung, V. The NLRP3 inflammasome renders cell death pro-inflammatory. J. Mol. Biol. 430, 133–141 (2018).

    Article  CAS  PubMed  Google Scholar 

  159. Gonugunta, V. K. et al. Trafficking-mediated STING degradation requires sorting to acidified endolysosomes and can be targeted to enhance anti-tumor response. Cell Rep. 21, 3234–3242 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  160. Trenner, A. & Sartori, A. A. Harnessing DNA double-strand break repair for cancer treatment. Front. Oncol. 9, 1388 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  161. Srikanth, S. et al. The Ca2+ sensor STIM1 regulates the type I interferon response by retaining the signaling adaptor STING at the endoplasmic reticulum. Nat. Immunol. 20, 152–162 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  162. Jonsson, K. L. et al. IFI16 is required for DNA sensing in human macrophages by promoting production and function of cGAMP. Nat. Commun. 8, 14391 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  163. Pokatayev, V. et al. Homeostatic regulation of STING protein at the resting state by stabilizer TOLLIP. Nat. Immunol. 21, 158–167 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  164. Ning, X. et al. Apoptotic caspases suppress type I interferon production via the cleavage of cGAS, MAVS, and IRF3. Mol. Cell 74, 19–31.e7 (2019).

    Article  CAS  PubMed  Google Scholar 

  165. Xia, P. et al. Glutamylation of the DNA sensor cGAS regulates its binding and synthase activity in antiviral immunity. Nat. Immunol. 17, 369–378 (2016).

    Article  CAS  PubMed  Google Scholar 

  166. Chen, M. et al. TRIM14 inhibits cGAS degradation mediated by selective autophagy receptor p62 to promote innate immune responses. Mol. Cell 64, 105–119 (2016).

    Article  CAS  PubMed  Google Scholar 

  167. Wang, Q. et al. The E3 ubiquitin ligase AMFR and INSIG1 bridge the activation of TBK1 kinase by modifying the adaptor STING. Immunity 41, 919–933 (2014).

    Article  CAS  PubMed  Google Scholar 

  168. Guo, Y. et al. Cutting edge: USP27X deubiquitinates and stabilizes the DNA sensor cGAS to regulate cytosolic DNA-mediated signaling. J. Immunol. 203, 2049–2054 (2019).

    Article  CAS  PubMed  Google Scholar 

  169. Tanaka, Y. & Chen, Z. J. STING specifies IRF3 phosphorylation by TBK1 in the cytosolic DNA signaling pathway. Sci. Signal. 5, ra20 (2012).

    Article  PubMed  PubMed Central  Google Scholar 

  170. Zhong, B. et al. The ubiquitin ligase RNF5 regulates antiviral responses by mediating degradation of the adaptor protein MITA. Immunity 30, 397–407 (2009).

    Article  CAS  PubMed  Google Scholar 

  171. Tsuchida, T. et al. The ubiquitin ligase TRIM56 regulates innate immune responses to intracellular double-stranded DNA. Immunity 33, 765–776 (2010).

    Article  CAS  PubMed  Google Scholar 

  172. Qin, Y. et al. RNF26 temporally regulates virus-triggered type I interferon induction by two distinct mechanisms. PLOS Pathog. 10, e1004358 (2014).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  173. Zhang, J., Hu, M. M., Wang, Y. Y. & Shu, H. B. TRIM32 protein modulates type I interferon induction and cellular antiviral response by targeting MITA/STING protein for K63-linked ubiquitination. J. Biol. Chem. 287, 28646–28655 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  174. Ni, G., Konno, H. & Barber, G. N. Ubiquitination of STING at lysine 224 controls IRF3 activation. Sci. Immunol. 2, eaah7119 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  175. Zhang, L. et al. The deubiquitinase CYLD is a specific checkpoint of the STING antiviral signaling pathway. PLOS Pathog. 14, e1007435 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  176. Sun, H. et al. USP13 negatively regulates antiviral responses by deubiquitinating STING. Nat. Commun. 8, 15534 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  177. Janeway, C. A. Jr. Approaching the asymptote? Evolution and revolution in immunology. Cold Spring Harb. Symp. Quant. Biol. 54, 1–13 (1989).

    Article  CAS  PubMed  Google Scholar 

  178. Gong, T., Liu, L., Jiang, W. & Zhou, R. DAMP-sensing receptors in sterile inflammation and inflammatory diseases. Nat. Rev. Immunol. 20, 95–112 (2020).

    Article  CAS  PubMed  Google Scholar 

  179. Roers, A., Hiller, B. & Hornung, V. Recognition of endogenous nucleic acids by the innate immune system. Immunity 44, 739–754 (2016). This review discusses the mechanisms of self versus non-self recognition in nucleic acid sensing.

    Article  CAS  PubMed  Google Scholar 

  180. Ma, Z. & Damania, B. The cGAS–STING defense pathway and its counteraction by viruses. Cell Host Microbe 19, 150–158 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  181. Li, T. & Chen, Z. J. The cGAS–cGAMP–STING pathway connects DNA damage to inflammation, senescence, and cancer. J. Exp. Med. 215, 1287–1299 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  182. Motwani, M., Pesiridis, S. & Fitzgerald, K. A. DNA sensing by the cGAS–STING pathway in health and disease. Nat. Rev. Genet. 20, 657–674 (2019).

    Article  CAS  PubMed  Google Scholar 

  183. Ching, L. M., Joseph, W. R. & Baguley, B. C. Antitumour responses to flavone-8-acetic acid and 5,6-dimethylxanthenone-4-acetic acid in immune deficient mice. Br. J. Cancer 66, 128–130 (1992).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  184. Kramer, M. J., Cleeland, R. & Grunberg, E. Antiviral activity of 10-carboxymethyl-9-acridanone. Antimicrob. Agents Chemother. 9, 233–238 (1976).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  185. Prantner, D. et al. 5,6-Dimethylxanthenone-4-acetic acid (DMXAA) activates stimulator of interferon gene (STING)-dependent innate immune pathways and is regulated by mitochondrial membrane potential. J. Biol. Chem. 287, 39776–39788 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  186. Cavlar, T., Deimling, T., Ablasser, A., Hopfner, K. P. & Hornung, V. Species-specific detection of the antiviral small-molecule compound CMA by STING. EMBO J. 32, 1440–1450 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  187. Daei Farshchi Adli, A., Jahanban-Esfahlan, R., Seidi, K., Samandari-Rad, S. & Zarghami, N. An overview on vadimezan (DMXAA): the vascular disrupting agent. Chem. Biol. Drug Des. 91, 996–1006 (2018).

    Article  CAS  PubMed  Google Scholar 

  188. Fu, J. et al. STING agonist formulated cancer vaccines can cure established tumors resistant to PD-1 blockade. Sci. Transl. Med. 7, 283ra252 (2015).

    Google Scholar 

  189. Demaria, O. et al. STING activation of tumor endothelial cells initiates spontaneous and therapeutic antitumor immunity. Proc. Natl Acad. Sci. USA 112, 15408–15413 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  190. Wang, H. et al. cGAS is essential for the antitumor effect of immune checkpoint blockade. Proc. Natl Acad. Sci. USA 114, 1637–1642 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  191. Woo, S. R. et al. STING-dependent cytosolic DNA sensing mediates innate immune recognition of immunogenic tumors. Immunity 41, 830–842 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  192. Ahn, J. et al. Inflammation-driven carcinogenesis is mediated through STING. Nat. Commun. 5, 5166 (2014).

    Article  CAS  PubMed  Google Scholar 

  193. Chen, Q. et al. Carcinoma–astrocyte gap junctions promote brain metastasis by cGAMP transfer. Nature 533, 493–498 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  194. Bakhoum, S. F. et al. Chromosomal instability drives metastasis through a cytosolic DNA response. Nature 553, 467–472 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  195. Vanpouille-Box, C., Hoffmann, J. A. & Galluzzi, L. Pharmacological modulation of nucleic acid sensors — therapeutic potential and persisting obstacles. Nat. Rev. Drug Discov. 18, 845–867 (2019).

    Article  CAS  PubMed  Google Scholar 

  196. Crow, Y. J. & Manel, N. Aicardi–Goutieres syndrome and the type I interferonopathies. Nat. Rev. Immunol. 15, 429–440 (2015).

    Article  CAS  PubMed  Google Scholar 

  197. Lee-Kirsch, M. A. et al. Mutations in the gene encoding the 3′–5′ DNA exonuclease TREX1 are associated with systemic lupus erythematosus. Nat. Genet. 39, 1065–1067 (2007).

    Article  CAS  PubMed  Google Scholar 

  198. Rice, G. et al. Heterozygous mutations in TREX1 cause familial chilblain lupus and dominant Aicardi–Goutieres syndrome. Am. J. Hum. Genet. 80, 811–815 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  199. An, J. et al. Expression of cyclic GMP–AMP synthase in patients with systemic lupus erythematosus. Arthritis Rheumatol. 69, 800–807 (2017).

    Article  CAS  PubMed  Google Scholar 

  200. Kerur, N. et al. cGAS drives noncanonical-inflammasome activation in age-related macular degeneration. Nat. Med. 24, 50–61 (2018).

    Article  CAS  PubMed  Google Scholar 

  201. Yu, Y. et al. STING-mediated inflammation in Kupffer cells contributes to progression of nonalcoholic steatohepatitis. J. Clin. Invest. 129, 546–555 (2019).

    Article  PubMed  Google Scholar 

  202. Sliter, D. A. et al. Parkin and PINK1 mitigate STING-induced inflammation. Nature 561, 258–262 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  203. King, K. R. et al. IRF3 and type I interferons fuel a fatal response to myocardial infarction. Nat. Med. 23, 1481–1487 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  204. Sintim, H. O., Mikek, C. G., Wang, M. & Sooreshjani, M. A. Interrupting cyclic dinucleotide–cGAS–STING axis with small molecules. MedChemComm 10, 1999–2023 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

The authors thank C. de Oliveira Mann and C. Stafford for discussions. The authors acknowledge support by Deutsche Forschungsgemeinschaft Grant TRR 237 (to K.-P.H. and V.H.), the Gottfried Wilhelm Leibniz-Prize (to K.-P.H. and V.H.) and by the European Reserach Council (ERC-2014-CoG – 647858 GENESIS to V.H.).

Author information

Authors and Affiliations

Authors

Contributions

The authors contributed equally to all aspects of the article.

Corresponding authors

Correspondence to Karl-Peter Hopfner or Veit Hornung.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information

Nature Reviews Molecular Cell Biology thanks P. Li, Z. Chen and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Related links

PDB ID 6CTA: https://www.rcsb.org/structure/6CTA

PDB ID 4KSY: https://www.rcsb.org/structure/4KSY

PDB ID 4KM5: https://www.rcsb.org/structure/4KM5

PDB ID 5N6I: https://www.rcsb.org/structure/5N6I

PDB ID 6EDB: https://www.rcsb.org/structure/6EDB

PDB ID 6NT6: https://www.rcsb.org/structure/6NT6

PDB ID 6NT7: https://www.rcsb.org/structure/6NT7

Glossary

Innate immune system

A heterogeneous system of molecules, signal transducers and cells that has evolved to detect invading microbes, and elicits a first line of antimicrobial defence and activates the adaptive immune system.

Pattern recognition receptors

(PPRs). Germline-encoded receptors of the innate immune system. They detect pathogen or danger/damage-associated molecular patterns and elicit cellular defence reactions.

Pathogen and damage-associated molecular patterns

(PAMPs and DAMPs). Molecules that signal the presence of pathogens (that is, PAMPs) or danger/damage (that is, DAMPs). They are recognized by pattern recognition receptors.

Adaptive immune system

A branch of the immune system that comprises B and T lymphocytes. It elicits a highly specific response to antigens through highly variable, clonally expressed B cell receptors/antibodies or T cell receptors.

Nucleotidyl transferase

(NTase). A class of enzymes that transfer nucleoside phosphates onto an acceptor, typically a hydroxyl group.

Cyclic dinucleotide

Two nucleoside phosphates, joined in a circular dinucleotide through two phosphodiester linkages. Cyclic dinucleotides are found in prokaryotes and higher eukaryotes, and typically have second messenger functions to regulate diverse activities, such as bacterial biofilm and planktonic lifestyles (c-di-GMP), osmolyte homeostasis (c-di-AMP) and eukaryotic innate immune signalling (cyclic GMP–AMP).

Cellular senescence

A state that is generally characterized by a permanent cell cycle arrest in the context of ageing or tumour suppression. It can be promoted by multiple factors, including oxidative stress, DNA damage, mitochondrial dysfunction and the unfolded protein response.

Aicardi–Goutières syndrome

A rare, genetically determined progressive encephalopathy with autoimmune features that is caused by mutations in various genes involved in nucleic acid metabolism.

Systemic lupus erythematosus

A systemic, chronic, autoimmune disease that affects connective tissue of the kidneys, heart, lungs, brain, blood and skin.

Liquid–liquid phase separation

In cell biology, the separation of macromolecules (proteins, nucleic acids) into two liquid-like phases with high and low concentrations of the macromolecule.

Major histocompatibility complex class II

(MHC II). Surface molecules, typically found on antigen presenting cells such as dendritic cells, macrophages and B cells, that display peptides derived from extracellular proteins for interaction with immune cells.

Dendritic cells

Specialized antigen-presenting cells in a heterogeneous group that act as a link between the innate and adaptive immune system. They take up and process antigens and induce naive T lymphocyte activation and effector cell differentiation.

Extracellular vesicles

Secreted vesicles produced by many cell types, including tumour cells that can carry a wide variety of cellular components, including DNA, RNA, proteins and other molecules. They include two main subpopulations known as microvesicles and exosomes that differ in their mode of biogenesis (plasma membrane versus endosomal origin).

Natural killer cells

Cytotoxic effector lymphocytes of the innate immune system that play critical roles in antitumour and antimicrobial defence.

BAK/BAX macropores

Pores in the outer membrane of mitochondria, formed by the BAK and BAX proteins to trigger cytochrome c release and apoptosis.

Effector caspases

Proteinases activated through cleavage by initiator caspases (caspase cascade) that then proteolytically cleave many target proteins to execute apoptosis.

Mitochondrial stress

Pathophysiological conditions leading to mitochondrial DNA stress, mitochondrial unfolded protein response and stress signalling pathways.

Nucleosomal arrays

Sequences of regularly spaced nucleosomes along the DNA, typically found at gene bodies of eukaryotic chromosomes.

Nucleosome core particles

Histone protein octamers together with ~147 bp of tightly wrapped DNA, which is protected from nuclease digestion.

Linker DNA

DNA connecting two adjacent nucleosome core particles. This can range in length in different species, cell types and loci.

Nuclear envelope blebbing

The formation of membrane bulges at the nuclear envelope. At these sites, the membrane separates from the underlying lamina, allowing the chromatin to herniate and protrude into the bleb. In the event of membrane rupture, blebbing results in exchanging material between cytosol and nucleoplasm.

Telomeres

Specialized protective end structures of linear chromosomes, consisting of a repetitive DNA sequence and associated proteins.

Senescence-associated cell cycle arrest

The shortening of telomeres leading to a prolonged DNA damage response and check-point activation to trigger a permanent cell cycle arrest, a hallmark of senescent cells.

Dicentric chromosomes

Chromosomes containing two centromeres formed through genome rearrangements.

Alternative lengthening of telomeres

(ALT). The telomerase-independent, recombination-dependent mode of extension of telomeres in cancer cells.

Autophagy

A regulated system in which the cell degrades unwanted cellular components by incorporation into autophagosomes followed by fusion with lysosomes.

γ-H2AX

The phosphorylation of histone 2A variant X at Ser139, leading to nucleosomes containing γ-H2AX. This mark is an early cellular response to DNA double-strand breaks, which serves in the recruitment of other repair factors.

Poly-ADP ribose polymerase 1

(PARP1). An enzyme that binds and marks DNA breaks by adding poly-ADP-ribose (PAR) onto itself and other targets.

LINE1

(Long interspersed nuclear element 1). A class I transposable element, typically 6 kb long, present in the genome of humans and some other organisms. LINE1 elements comprise around 17% of the human genome.

Homologous recombination

A DNA double-strand break repair pathway in which a DNA end is resected, and the resulting single-strand is extended on a homologous template

Gap junctions

Specialized cell–cell channels formed by juxtaposed connexon pores of adjacent cells, allowing the cytoplasmic exchange of small molecules and ions.

TIMELESS

A protein implicated in the circadian rhythm, replication and enhancing homologous recombination through interactions with different proteins.

Non-homologous end-joining

A DNA double-strand break repair pathway in which two DNA ends are directly ligated, often after limited processing by nucleases and DNA polymerases, in a pathway that depends on DNA-dependent protein kinase and DNA ligase IV.

COPII coat complex

A protein complex in the secretory pathway composed of five proteins that coats membrane vesicles transporting material from the endoplasmic reticulum to the Golgi apparatus.

ER–Golgi intermediate compartment

(ERGIC). An organellar structure that mediates trafficking between the endoplasmic reticulum (ER) and the Golgi apparatus.

Palmitoylation

A lipid modification of proteins through covalent attachment of palmitic acid, regulating different properties of proteins, such as membrane interaction, stability and trafficking.

MAPK

A type of protein kinase that transduces extracellular signals, such as growth factors, cytokines and mitogens, to cellular programmes, such as growth, differentiation, inflammation and others.

LC3

(Also known as microtubule-associated proteins 1A/1B light chain 3B). A protein that functions in substrate selection in autophagy and is used as a marker for autophagosomes.

SAVI

(STING-associated vasculopathy with onset in infancy). A rare autoinflammatory vasculopathy characterized by severe skin lesions and interstitial lung disease.

NLRP3 inflammasome

A multiprotein complex that initiates a pro-inflammatory cell death with the release of IL-1β in response to activation by NLRP3, which senses microbial and endogenous danger signals.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Hopfner, KP., Hornung, V. Molecular mechanisms and cellular functions of cGAS–STING signalling. Nat Rev Mol Cell Biol 21, 501–521 (2020). https://doi.org/10.1038/s41580-020-0244-x

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41580-020-0244-x

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing