NLRP3 phosphorylation in its LRR domain critically regulates inflammasome assembly

Nat Commun. 2021 Oct 6;12(1):5862. doi: 10.1038/s41467-021-26142-w.


NLRP3 controls the secretion of inflammatory cytokines IL-1β/18 and pyroptosis by assembling the inflammasome. Upon coordinated priming and activation stimuli, NLRP3 recruits NEK7 within hetero-oligomers that nucleate ASC and caspase-1 filaments, but the apical molecular mechanisms underlying inflammasome assembly remain elusive. Here we show that NEK7 recruitment to NLRP3 is controlled by the phosphorylation status of NLRP3 S803 located within the interaction surface, in which NLRP3 S803 is phosphorylated upon priming and later dephosphorylated upon activation. Phosphomimetic substitutions of S803 abolish NEK7 recruitment and inflammasome activity in macrophages in vitro and in vivo. In addition, NLRP3-NEK7 binding is also essential for NLRP3 deubiquitination by BRCC3 and subsequently inflammasome assembly, with NLRP3 phosphomimetic mutants showing enhanced ubiquitination and degradation than wildtype NLRP3. Finally, we identify CSNK1A1 as the kinase targeting NLRP3 S803. Our findings thus reveal NLRP3 S803 phosphorylation status as a druggable apical molecular mechanism controlling inflammasome assembly.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Casein Kinase II
  • Casein Kinase Ialpha
  • Caspase 1 / metabolism
  • Cytokines / metabolism
  • Deubiquitinating Enzymes
  • HEK293 Cells
  • Humans
  • Inflammasomes / metabolism*
  • Macrophages / metabolism
  • Mice
  • Mice, Knockout
  • NIMA-Related Kinases / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein / chemistry*
  • NLR Family, Pyrin Domain-Containing 3 Protein / genetics*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism*
  • Phosphorylation
  • Pyroptosis
  • Ubiquitination


  • Cytokines
  • Inflammasomes
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • NLRP3 protein, human
  • Nlrp3 protein, mouse
  • CSNK1A1 protein, human
  • Casein Kinase II
  • Casein Kinase Ialpha
  • Csnk2a1 protein, mouse
  • NIMA-Related Kinases
  • Nek7 protein, mouse
  • BRCC3 protein, mouse
  • Deubiquitinating Enzymes
  • Caspase 1