Tonic prime-boost of STING signalling mediates Niemann-Pick disease type C

Nature. 2021 Aug;596(7873):570-575. doi: 10.1038/s41586-021-03762-2. Epub 2021 Jul 21.

Abstract

The classic mode of STING activation is through binding the cyclic dinucleotide 2'3'-cyclic GMP-AMP (cGAMP), produced by the DNA sensor cyclic GMP-AMP synthase (cGAS), which is important for the innate immune response to microbial infection and autoimmune disease. Modes of STING activation that are independent of cGAS are much less well understood. Here, through a spatiotemporally resolved proximity labelling screen followed by quantitative proteomics, we identify the lysosomal membrane protein Niemann-Pick type C1 (NPC1) as a cofactor in the trafficking of STING. NPC1 interacts with STING and recruits it to the lysosome for degradation in both human and mouse cells. Notably, we find that knockout of Npc1 'primes' STING signalling by physically linking or 'tethering' STING to SREBP2 trafficking. Loss of NPC1 protein also 'boosts' STING signalling by blocking lysosomal degradation. Both priming and boosting of STING signalling are required for severe neurological disease in the Npc1-/- mouse. Genetic deletion of Sting1 (the gene that encodes STING) or Irf3, but not that of Cgas, significantly reduced the activation of microglia and relieved the loss of Purkinje neurons in the cerebellum of Npc1-/- mice, leading to improved motor function. Our study identifies a cGAS- and cGAMP-independent mode of STING activation that affects neuropathology and provides a therapeutic target for the treatment of Niemann-Pick disease type C.

Publication types

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

MeSH terms

  • Animals
  • Cell Line
  • Cerebellum / pathology
  • Endoplasmic Reticulum / metabolism
  • Golgi Apparatus / metabolism
  • Humans
  • Interferon Regulatory Factor-3 / metabolism
  • Interferon Type I / immunology
  • Lysosomes / metabolism
  • Membrane Proteins / deficiency
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Microglia / metabolism
  • Models, Biological*
  • Motor Skills
  • Neuroinflammatory Diseases
  • Niemann-Pick C1 Protein / deficiency
  • Niemann-Pick C1 Protein / genetics
  • Niemann-Pick C1 Protein / metabolism
  • Niemann-Pick Disease, Type C / metabolism*
  • Niemann-Pick Disease, Type C / pathology
  • Nucleotides, Cyclic / metabolism
  • Nucleotidyltransferases / metabolism
  • Protein Serine-Threonine Kinases / metabolism
  • Protein Transport
  • Proteolysis
  • Purkinje Cells / metabolism
  • Signal Transduction*
  • Sterol Regulatory Element Binding Protein 2 / metabolism

Substances

  • Interferon Regulatory Factor-3
  • Interferon Type I
  • Irf3 protein, mouse
  • Membrane Proteins
  • NPC1 protein, human
  • Niemann-Pick C1 Protein
  • Npc1 protein, mouse
  • Nucleotides, Cyclic
  • STING1 protein, human
  • Sterol Regulatory Element Binding Protein 2
  • Sting1 protein, mouse
  • cyclic guanosine monophosphate-adenosine monophosphate
  • Tbk1 protein, mouse
  • Protein Serine-Threonine Kinases
  • TBK1 protein, human
  • Nucleotidyltransferases
  • cGAS protein, mouse