title: Cryopyrin activates the inflammasome in response to toxins and ATP.
abstract: A crucial part of the innate immune response is the assembly of the inflammasome, a cytosolic complex of proteins that activates caspase-1 to process the proinflammatory cytokines interleukin (IL)-1beta and IL-18. The adaptor protein ASC is essential for inflammasome function, binding directly to caspase-1 (refs 3, 4), but the triggers of this interaction are less clear. ASC also interacts with the adaptor cryopyrin (also known as NALP3 or CIAS1). Activating mutations in cryopyrin are associated with familial cold autoinflammatory syndrome, Muckle-Wells syndrome and neonatal onset multisystem inflammatory disease, diseases that are characterized by excessive production of IL-1beta. Here we show that cryopyrin-deficient macrophages cannot activate caspase-1 in response to Toll-like receptor agonists plus ATP, the latter activating the P2X7 receptor to decrease intracellular K+ levels. The release of IL-1beta in response to nigericin, a potassium ionophore, and maitotoxin, a potent marine toxin, was also found to be dependent on cryopyrin. In contrast to Asc-/- macrophages, cells deficient in the gene encoding cryopyrin (Cias1-/-) activated caspase-1 and secreted normal levels of IL-1beta and IL-18 when infected with Gram-negative Salmonella typhimurium or Francisella tularensis. Macrophages exposed to Gram-positive Staphylococcus aureus or Listeria monocytogenes, however, required both ASC and cryopyrin to activate caspase-1 and secrete IL-1beta. Therefore, cryopyrin is essential for inflammasome activation in response to signalling pathways triggered specifically by ATP, nigericin, maitotoxin, S. aureus or L. monocytogenes.
authors.affiliation: Molecular Oncology Department, Genentech Inc, 1 DNA Way, South San Francisco, California 94080, USA.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Mariathasan
authors.forename: David S
authors.initials: DS
authors.lastname: Weiss
authors.forename: Kim
authors.initials: K
authors.lastname: Newton
authors.forename: Jacqueline
authors.initials: J
authors.lastname: McBride
authors.forename: Karen
authors.initials: K
authors.lastname: O'Rourke
authors.forename: Meron
authors.initials: M
authors.lastname: Roose-Girma
authors.forename: Wyne P
authors.initials: WP
authors.lastname: Lee
authors.forename: Yvette
authors.initials: Y
authors.lastname: Weinrauch
authors.forename: Denise M
authors.initials: DM
authors.lastname: Monack
authors.forename: Vishva M
authors.initials: VM
authors.lastname: Dixit
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D053468:CARD Signaling Adaptor Proteins; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D020170:Caspase 1 / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D007249:Inflammation / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D007375:Interleukin-1 / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D008089:Listeria monocytogenes / Q000235:genetics / Q000276:immunology / Q000502:physiology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D008387:Marine Toxins / Q000494:pharmacology; D051379:Mice; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein; D009550:Nigericin / Q000494:pharmacology; D053473:Nod2 Signaling Adaptor Protein; D035964:Oxocins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D013211:Staphylococcus aureus / Q000276:immunology / Q000502:physiology; D051193:Toll-Like Receptors / Q000819:agonists / Q000276:immunology / Q000378:metabolism; D014118:Toxins, Biological / Q000494:pharmacology*; D000095702:Polyether Toxins
chemical_list: D000255:Adenosine Triphosphate; D051017:Apoptosis Regulatory Proteins; D053468:CARD Signaling Adaptor Proteins; D002352:Carrier Proteins; D020170:Caspase 1; D003598:Cytoskeletal Proteins; D048049:Extracellular Signal-Regulated MAP Kinases; D007375:Interleukin-1; D047908:Intracellular Signaling Peptides and Proteins; D008387:Marine Toxins; D046912:Multiprotein Complexes; D016328:NF-kappa B; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein; D009550:Nigericin; D053473:Nod2 Signaling Adaptor Protein; D035964:Oxocins; D051193:Toll-Like Receptors; D014118:Toxins, Biological; C492716:Nlrp3 protein, mouse; C495945:Nod2 protein, mouse; C498534:Pycard protein, mouse; C020394:maitotoxin; D000095702:Polyether Toxins