Structure, Activation and Regulation of NLRP3 and AIM2 Inflammasomes

Int J Mol Sci. 2021 Jan 16;22(2):872. doi: 10.3390/ijms22020872.

Abstract

The inflammasome is a three-component (sensor, adaptor, and effector) filamentous signaling platform that shields from multiple pathogenic infections by stimulating the proteolytical maturation of proinflammatory cytokines and pyroptotic cell death. The signaling process initiates with the detection of endogenous and/or external danger signals by specific sensors, followed by the nucleation and polymerization from sensor to downstream adaptor and then to the effector, caspase-1. Aberrant activation of inflammasomes promotes autoinflammatory diseases, cancer, neurodegeneration, and cardiometabolic disorders. Therefore, an equitable level of regulation is required to maintain the equilibrium between inflammasome activation and inhibition. Recent advancement in the structural and mechanistic understanding of inflammasome assembly potentiates the emergence of novel therapeutics against inflammasome-regulated diseases. In this review, we have comprehensively discussed the recent and updated insights into the structure of inflammasome components, their activation, interaction, mechanism of regulation, and finally, the formation of densely packed filamentous inflammasome complex that exists as micron-sized punctum in the cells and mediates the immune responses.

Keywords: AIM2; ASC (apoptosis-associated speck-like protein containing a CARD), NLRP3; NMR; inflammation; protein assembly; protein structure.

Publication types

  • Review

MeSH terms

  • Animals
  • CARD Signaling Adaptor Proteins / chemistry
  • CARD Signaling Adaptor Proteins / metabolism
  • Caspase 1 / chemistry
  • Caspase 1 / metabolism
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / metabolism*
  • Humans
  • Inflammasomes / chemistry
  • Inflammasomes / metabolism*
  • NLR Family, Pyrin Domain-Containing 3 Protein / chemistry
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism*
  • Protein Domains
  • Protein Multimerization

Substances

  • AIM2 protein, human
  • CARD Signaling Adaptor Proteins
  • DNA-Binding Proteins
  • Inflammasomes
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Caspase 1