Proteasomal degradation of NOD2 by NLRP12 in monocytes promotes bacterial tolerance and colonization by enteropathogens

Nat Commun. 2018 Dec 17;9(1):5338. doi: 10.1038/s41467-018-07750-5.


Mutations in the nucleotide-binding oligomerization domain protein 12 (NLRP12) cause recurrent episodes of serosal inflammation. Here we show that NLRP12 efficiently sequesters HSP90 and promotes K48-linked ubiquitination and degradation of NOD2 in response to bacterial muramyl dipeptide (MDP). This interaction is mediated by the linker-region proximal to the nucleotide-binding domain of NLRP12. Consequently, the disease-causing NLRP12 R284X mutation fails to repress MDP-induced NF-κB and subsequent activity of the JAK/STAT signaling pathway. While NLRP12 deficiency renders septic mice highly susceptible towards MDP, a sustained sensing of MDP through NOD2 is observed among monocytes lacking NLRP12. This loss of tolerance in monocytes results in greater colonization resistance towards Citrobacter rodentium. Our data show that this is a consequence of NOD2-dependent accumulation of inflammatory mononuclear cells that correlates with induction of interferon-stimulated genes. Our study unveils a relevant process of tolerance towards the gut microbiota that is exploited by an attaching/effacing enteric pathogen.

MeSH terms

  • Acetylmuramyl-Alanyl-Isoglutamine / metabolism*
  • Animals
  • Bacterial Capsules / metabolism*
  • Cell Line
  • Citrobacter rodentium / immunology*
  • Enterobacteriaceae Infections / immunology*
  • Enterobacteriaceae Infections / microbiology
  • Gastrointestinal Microbiome / immunology
  • HEK293 Cells
  • HSP90 Heat-Shock Proteins / metabolism*
  • Humans
  • Immune Tolerance / immunology*
  • Inflammation / immunology
  • Inflammation / microbiology
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Male
  • Mice
  • Mice, Knockout
  • NF-kappa B / metabolism
  • Nod2 Signaling Adaptor Protein / metabolism*
  • Ubiquitination


  • HSP90 Heat-Shock Proteins
  • Intracellular Signaling Peptides and Proteins
  • K48 capsular polysaccharide, Escherichia coli
  • NF-kappa B
  • NLRP12 protein, mouse
  • Nod2 Signaling Adaptor Protein
  • Nod2 protein, mouse
  • Acetylmuramyl-Alanyl-Isoglutamine